ELEVATOR APPARATUS
United States Patent 3850106
The specification herein discloses elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths. The apparatus comprises an elevator subassembly and an infeed subassembly. The former comprises two pairs of controlled-pathway propulsion means each of which carries a plurality of vertical lift pick-up bars therebetween in a manner permitting the cars of the unit carrier system to be picked up by two bars, one associated with each pair of controlled-pathway propulsion means, and carried from one level to another thereby. The latter comprises a movable member having means for releasably engaging a suitable surface on each car and synchronizing means adapted to cause the movable member to propel the car into position to be picked up by the pick-up bars at or before the time the bars come into position to pick up the cars.
US Patent References:
Conveyer system
De Witt - August 1934 - 1969122
Level and inclined conveyor
Da Costa - August 1957 - 2802427
Continuous and reversible vertical conveyor
De Good - August 1966 - 3268061
Conveyer system
De Witt - August 1934 - 1969122
Level and inclined conveyor
Da Costa - August 1957 - 2802427
Continuous and reversible vertical conveyor
De Good - August 1966 - 3268061
Application Number:
05/420499
Publication Date:
11/26/1974
Filing Date:
11/30/1973
View Patent Images:
Export Citation:
Assignee:
Rexnord Inc. (Milwaukee, WI)
Primary Class:
Other Classes:
198/610, 198/465.300, 198/799
International Classes:
B61B9/00; B61B3/00
Field of Search:
104/127,128,129 198/20,153,78,26,38,154,163
Primary Examiner:
Wood Jr., Henson M.
Assistant Examiner:
Keen D. W.
Attorney, Agent or Firm:
Sughrue, Rothwell, Mion, Zinn & Macpeak
Claims:
What is claimed is
1. Elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said apparatus comprising:
2. a first pair of controlled-pathway propulsion means mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in said unit carrier system, each of said first pair of controlled-pathway propulsion means having:
3. a first plurality of vertical lift pick-up bars carried by said first pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said first pair of controlled-pathway propulsion means, said first plurality of bars being spaced by a distance at least slightly longer than said first distance;
4. a second pair of controlled-pathway propulsion means mounted in parallel, spaced relationship immediately adjacent to and parallel to said first pair of controlled-pathway propulsion means, each of said second pair of controlled-pathway propulsion means having:
5. a second plurality of vertical left pick-up bars carried by said second pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said second pair of controlled-pathway propulsion means, each one of said second plurality of vertical lift pick-up bars being associated with a corresponding one of said first plurality of vertical lift pick-up bars and spaced therebehind by a second distance, which second distance is less than the length of the shortest car in said unit carrier system, at least one of said first and second pluralities of vertical left pick-up bars being carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the respective one of said pairs of controlled-pathway propulsion means;
6. means for driving said first and second pairs of controlled-pathway propulsion means at the same speed and in the same direction;
7. first lodgment means for one of said first plurality of vertical lift pick-up bars located on the underside of said cars at a point close enough to the front end thereof when said cars are stopped at said stopping point so that said first lodgment means is located in front of the center of gravity of said cars under any possible load conditions;
8. means for positioning a car stopped at said stopping point in a position such that one of said first plurality of vertical left pick-up bars will lodge in said first lodgment means, thereby drawing said car forward along the entry legs of said first pair of controlled-pathway propulsion means; and
9. second lodgment means for said second plurality of vertical lift pick-up bars located on the underside of said cars said second distance back from said first lodgment means provided that said second distance is sufficiently long so that said second lodgment means is located behind the center of gravity of said cars under any possible load conditions, whereby the one of said second plurality of vertical lift pick-up bars associated with the one of said first plurality of vertical lift pick-up bars which has lodged in said first lodgment means will lodge in said second lodgment means,
10. Elevator apparatus as claimed in claim 1 wherein each of said controlled-pathway propulsion means comprises:
11. a plurality of sprockets mounted on shafts extending exteriorly of the space in which said cars are moved, said sprockets being mounted so as to define the juncture of the previously recited legs of said controlled-pathway propulsion means, and
12. an endless chain passing over said plurality of sprockets and being of a length which is the same integral multiple of the distance by which said vertical lift pick-up bars are spaced.
13. Elevator apparatus as claimed in claim 1 wherein both of said first pair of controlled-pathway propulsion means are mounted either interiorly or exteriorly of the adjacent one of said second pair of controlled-pathway propulsion means.
14. Elevator apparatus as claimed in claim 1 wherein said means for positioning a car stopped at said stopping point comprise:
15. an engagement surface located on the exterior of each of said cars in a predetermined relationship to said first lodgment means;
16. a movable member having means for releasably engaging said engagement surface on one of said cars when said car is stopped at said stopping point, said movable member being movable between a first position in which it engages said engagement surface on said car while said car is at said stopping point and a second position in which it releases the engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means; and
17. means for synchronizing the motion of said movable member with the motion of said first plurality of vertical lift pick-up bars such that said movable member is moved from its first to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
18. Elevator apparatus as claimed in claim 4 wherein:
19. said movable member is pivotably mounted at a central point, has means for releasably engaging said engagement surfaces on one side of said central point, and has a partial sprocket on the other side of said central point and
20. said means for synchronizing comprise a sprocket-mounted endless chain which, over a portion of its length, is a double chain, the doubling chain thereof being positioned to engage the partial sprocket on said movable member, thereby causing said movable member to be pivoted from its first position to its second position every time the doubling chain comes into engagement with the partial sprocket, said sprocket-mounted endless chain being driven at a rate such that the doubling chain comes into engagement with the partial sprocket one time for every time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
21. Elevator apparatus as claimed in claim 4 wherein:
22. said movable member is pivotably mounted at a central point and has means for releasably engaging said engagement surfaces on one side of said central point and
23. said means for synchronizing comprise:
24. Elevator apparatus as claimed in claim 4 wherein:
25. said movable member is pivotably mounted about a fixed point at one end thereof and has means for releasably engaging said engagement surfaces at the other end thereof and
26. said means for synchronizing comprise:
27. Elevator apparatus as claimed in claim 7 wherein said means for pivoting said movable member comprises:
28. a sprocket-mounted chain one end of which is connected to said movable member at a point remote from said fixed point;
29. a rod one end of which is connected to the other end of said sprocket-mounted chain;
30. means for causing said rod to be moved in a direction causing said sprocket-mounted chain to be passed around its mounting sprocket one time for every time one of said first plurality of pick-up bars approach the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said movable member to be pivoted from its first position to its second position.
31. Elevator apparatus as claimed in claim 4 wherein said movable member is connected to a shock absorber for absorbing some or all of the impact shock when said engagement surface comes into contact with said movable member.
32. Elevator apparatus as claimed in claim 1 wherein said means for positioning a car stopped at said stopping point comprise:
33. an engagement surface located on the exterior of each of said cars in a predetermined relationship to said first lodgment means;
34. a first movable member pivotably connected to a second movable member to be recited and movable between a first position in which it engages said engagement surface on a car stopped at said stopping point and a second position in which it releases said engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means;
35. a second movable member, said movable member being movable between a first position in which said first movable member connected thereto is in position to engage the engagement surface on a car stopped at said stopping point and a second position in which said first movable member connected thereto is in its second position; and
36. means for synchronizing the motion of said second movable member with the motion of said first plurality of vertical pick-up bars such that said second movable member is moved from its first position to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said car to be moved into position to be picked up by one of said first plurality of vertical lift pick-up bars at the proper time.
37. Elevator apparatus as claimed in claim 10 wherein:
38. said second movable member is pivoted about a central point and
39. said means for synchronizing comprise a sprocket-mounted endless chain bearing means for causing the pivoting of said second movable member from its first position to its second position about said central point one time for every one time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
40. Elevator apparatus as claimed in claim 10 wherein:
41. said second movable member is pivoted about a first point at one end thereof and
42. said means for synchronizing comprise a fluid cylinder connected to said second movable member at a second point remote from said first point.
43. An elevator subassembly for elevator apparatus adapted to move from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said subassembly comprising:
44. a first pair of controlled-pathway propulsion means mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in said unit carrier system, each of said first pair of controlled-pathway propulsion means having:
45. a first plurality of vertical lift pick-up bars carried by said first pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said first pair of controlled-pathway propulsion means, said first plurality of bars being spaced at a distance at least slightly longer than said first distance;
46. a second pair of controlled-pathway propulsion means mounted in parallel, spaced relationship immediately adjacent to and parallel to said first pair of controlled-pathway propulsion means, each of said second pair of controlled-pathway propulsion means having:
47. a second plurality of vertical lift pick-up bars carried by said second pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said second pair of controlled-pathway propulsion means, each one of said second plurality of vertical lift pick-up bars being associated with a corresponding one of said first plurality of vertical lift pick-up bars and spaced therebehind by a second distance, which second distance is less than the length of the shortest car in said unit carrier system, at least one of said first and second pluralities of vertical lift pick-up bars being carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the respective one of said pairs of controlled-pathway propulsion means; and
48. means for driving said first and second pairs of controlled-pathway propulsion means at the same speed, and in the same direction.
49. An elevator subassembly as claimed in claim 13 wherein each of said controlled-pathway propulsion means comprises:
50. a plurality of sprockets mounted on shafts extending exteriorly of the space in which said cars are moved, said sprockets being mounted so as to define the juncture of the previously recited legs of said controlled-pathway propulsion means, and
51. an endless chain passing over said plurality of sprockets and being of a length which is the same integral multiple of the distance by which said vertical lift pick-up bars are spaced.
52. Elevator apparatus as claimed in claim 13 wherein both of said first pair of controlled-pathway propulsion means are mounted either interiorly or exteriorly of the adjacent one of said second pair of controlled-pathway propulsion means.
53. In elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said elevator apparatus comprising first and second pluralities of vertical pick-up bars which are moved so that each car is picked up at a car stopping point by one bar from each of said pluralities of bars and carried to another level and each of said cars having first and second lodgment means for one bar from each of said pluralities of bars respectively and an engagement surface located on the exterior thereof in a predetermined relationship to said first lodgment means, an infeed subassembly comprising means for positioning a car stopped at said stopping point to receive one of said first plurality of vertical pick-up bars in said first lodgment means, said means comprising:
54. a movable member having means for releasably engaging said engagement surface on one of said cars when said car is stopped at said stopping point, said movable member being movable between a first position in which it engages said engagement surface on said car while said car is at said stopping point and a second position in which it releases the engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means; and
55. means for synchronizing the motion of said movable member with the motion of said first plurality of vertical lift pick-up bars such that said movable member is moved from its first to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controled-pathway propulsion means adjacent to said stopping point.
56. An infeed subassembly as claimed in claim 16 wherein:
57. said movable member is pivotably mounted at a central point, has means for releasably engaging said engagement surfaces on one side of said central point, and has a partial sprocket on the other side of said central point and
58. said means for synchronizing comprises a sprocket-mounted endless chain which, over a portion of its length, is a double chain, the doubling chain thereof being positioned to engage the partial sprocket on said movable member, thereby causing said movable member to be pivoted from its first position to its second position every time the doubling chain comes into engagement with the partial sprocket, said sprocket-mounted endless chain being driven at a rate such that the doubling chain comes into engagement with the partial sprocket one time for every time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
59. Elevator apparatus as claimed in claim 16 wherein:
60. said movable member is pivotably mounted at a central point and has means for releasably engaging said engagement surfaces on one side of said central point and
61. said means for synchronizing comprise:
62. Elevator apparatus as claimed in claim 16 wherein:
63. said movable member is pivotably mounted about a fixed point at one end thereof and has means for releasably engaging said engagement surfaces at the other end thereof and
64. said means for synchronizing comprise:
65. Elevator apparatus as claimed in claim 19 wherein said means for pivoting said movable member comprises:
66. a sprocket-mounted chain one end of which is connected to said movable member at a point remote from said fixed point;
67. a rod one end of which is connected to the other end of said sprocket-mounted chain;
68. means for causing said rod to be moved in a direction causing said sprocket-mounted chain to be passed around its mounting sprocket one time for every time one of said first plurality of pick-up bars approach the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said movable member to be pivoted from its first position to its second position.
69. Elevator apparatus as claimed in claim 16 wherein said movable member is connected to a shock absorber for absorbing some or all of the impact shock when said engagement surface comes into contact with said movable member.
70. In elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said elevator apparatus comprising first and second pluralities of vertical lift pick-up bars which are moved so that each car is picked up at a car stopping point by one bar from each of said pluralities of bars and carried to another level and each of said cars having first and second lodgment means for one bar for each of said pluralities of bars respectively and an engagement surface located on the exterior thereof in a predetermined relationship to said first lodgment means, an infeed subassembly comprising means for positioning a car stopped at said stopping point to receive one of said first plurality of vertical lift pick-up bars in said first lodgment means, said means comprising:
71. a first movable member pivotably connected to a second movable member to be recited and movable between a first position in which it engages said engagement surface on a car stopped at said stopping point and a second position in which it releases said engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means;
72. a second movable member, said movable member being movable between a first position in which said first movable member connected thereto is in position to engage the engagement surface on a car stopped at said stopping point and a second position in which said first movable member connected thereto is in its second position; and
73. means for synchronizing the motion of said second movable member with the motion of said first plurality of vertical lift pick-up bars such that said second movable member is moved from its first position to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said car to be moved into position to be picked up by one of said first plurality of vertical lift pick-up bars at the proper time.
74. An infeed subassembly as claimed in claim 22 wherein:
75. said second movable member is pivoted about a central point and
76. said means for synchronizing comprise a sprocket-mounted endless chain bearing means for causing the pivoting of said second movable member from its first position to its second position about said central point one time for every one time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
1. Elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said apparatus comprising:
2. a first pair of controlled-pathway propulsion means mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in said unit carrier system, each of said first pair of controlled-pathway propulsion means having:
3. a first plurality of vertical lift pick-up bars carried by said first pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said first pair of controlled-pathway propulsion means, said first plurality of bars being spaced by a distance at least slightly longer than said first distance;
4. a second pair of controlled-pathway propulsion means mounted in parallel, spaced relationship immediately adjacent to and parallel to said first pair of controlled-pathway propulsion means, each of said second pair of controlled-pathway propulsion means having:
5. a second plurality of vertical left pick-up bars carried by said second pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said second pair of controlled-pathway propulsion means, each one of said second plurality of vertical lift pick-up bars being associated with a corresponding one of said first plurality of vertical lift pick-up bars and spaced therebehind by a second distance, which second distance is less than the length of the shortest car in said unit carrier system, at least one of said first and second pluralities of vertical left pick-up bars being carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the respective one of said pairs of controlled-pathway propulsion means;
6. means for driving said first and second pairs of controlled-pathway propulsion means at the same speed and in the same direction;
7. first lodgment means for one of said first plurality of vertical lift pick-up bars located on the underside of said cars at a point close enough to the front end thereof when said cars are stopped at said stopping point so that said first lodgment means is located in front of the center of gravity of said cars under any possible load conditions;
8. means for positioning a car stopped at said stopping point in a position such that one of said first plurality of vertical left pick-up bars will lodge in said first lodgment means, thereby drawing said car forward along the entry legs of said first pair of controlled-pathway propulsion means; and
9. second lodgment means for said second plurality of vertical lift pick-up bars located on the underside of said cars said second distance back from said first lodgment means provided that said second distance is sufficiently long so that said second lodgment means is located behind the center of gravity of said cars under any possible load conditions, whereby the one of said second plurality of vertical lift pick-up bars associated with the one of said first plurality of vertical lift pick-up bars which has lodged in said first lodgment means will lodge in said second lodgment means,
10. Elevator apparatus as claimed in claim 1 wherein each of said controlled-pathway propulsion means comprises:
11. a plurality of sprockets mounted on shafts extending exteriorly of the space in which said cars are moved, said sprockets being mounted so as to define the juncture of the previously recited legs of said controlled-pathway propulsion means, and
12. an endless chain passing over said plurality of sprockets and being of a length which is the same integral multiple of the distance by which said vertical lift pick-up bars are spaced.
13. Elevator apparatus as claimed in claim 1 wherein both of said first pair of controlled-pathway propulsion means are mounted either interiorly or exteriorly of the adjacent one of said second pair of controlled-pathway propulsion means.
14. Elevator apparatus as claimed in claim 1 wherein said means for positioning a car stopped at said stopping point comprise:
15. an engagement surface located on the exterior of each of said cars in a predetermined relationship to said first lodgment means;
16. a movable member having means for releasably engaging said engagement surface on one of said cars when said car is stopped at said stopping point, said movable member being movable between a first position in which it engages said engagement surface on said car while said car is at said stopping point and a second position in which it releases the engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means; and
17. means for synchronizing the motion of said movable member with the motion of said first plurality of vertical lift pick-up bars such that said movable member is moved from its first to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
18. Elevator apparatus as claimed in claim 4 wherein:
19. said movable member is pivotably mounted at a central point, has means for releasably engaging said engagement surfaces on one side of said central point, and has a partial sprocket on the other side of said central point and
20. said means for synchronizing comprise a sprocket-mounted endless chain which, over a portion of its length, is a double chain, the doubling chain thereof being positioned to engage the partial sprocket on said movable member, thereby causing said movable member to be pivoted from its first position to its second position every time the doubling chain comes into engagement with the partial sprocket, said sprocket-mounted endless chain being driven at a rate such that the doubling chain comes into engagement with the partial sprocket one time for every time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
21. Elevator apparatus as claimed in claim 4 wherein:
22. said movable member is pivotably mounted at a central point and has means for releasably engaging said engagement surfaces on one side of said central point and
23. said means for synchronizing comprise:
24. Elevator apparatus as claimed in claim 4 wherein:
25. said movable member is pivotably mounted about a fixed point at one end thereof and has means for releasably engaging said engagement surfaces at the other end thereof and
26. said means for synchronizing comprise:
27. Elevator apparatus as claimed in claim 7 wherein said means for pivoting said movable member comprises:
28. a sprocket-mounted chain one end of which is connected to said movable member at a point remote from said fixed point;
29. a rod one end of which is connected to the other end of said sprocket-mounted chain;
30. means for causing said rod to be moved in a direction causing said sprocket-mounted chain to be passed around its mounting sprocket one time for every time one of said first plurality of pick-up bars approach the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said movable member to be pivoted from its first position to its second position.
31. Elevator apparatus as claimed in claim 4 wherein said movable member is connected to a shock absorber for absorbing some or all of the impact shock when said engagement surface comes into contact with said movable member.
32. Elevator apparatus as claimed in claim 1 wherein said means for positioning a car stopped at said stopping point comprise:
33. an engagement surface located on the exterior of each of said cars in a predetermined relationship to said first lodgment means;
34. a first movable member pivotably connected to a second movable member to be recited and movable between a first position in which it engages said engagement surface on a car stopped at said stopping point and a second position in which it releases said engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means;
35. a second movable member, said movable member being movable between a first position in which said first movable member connected thereto is in position to engage the engagement surface on a car stopped at said stopping point and a second position in which said first movable member connected thereto is in its second position; and
36. means for synchronizing the motion of said second movable member with the motion of said first plurality of vertical pick-up bars such that said second movable member is moved from its first position to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said car to be moved into position to be picked up by one of said first plurality of vertical lift pick-up bars at the proper time.
37. Elevator apparatus as claimed in claim 10 wherein:
38. said second movable member is pivoted about a central point and
39. said means for synchronizing comprise a sprocket-mounted endless chain bearing means for causing the pivoting of said second movable member from its first position to its second position about said central point one time for every one time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
40. Elevator apparatus as claimed in claim 10 wherein:
41. said second movable member is pivoted about a first point at one end thereof and
42. said means for synchronizing comprise a fluid cylinder connected to said second movable member at a second point remote from said first point.
43. An elevator subassembly for elevator apparatus adapted to move from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said subassembly comprising:
44. a first pair of controlled-pathway propulsion means mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in said unit carrier system, each of said first pair of controlled-pathway propulsion means having:
45. a first plurality of vertical lift pick-up bars carried by said first pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said first pair of controlled-pathway propulsion means, said first plurality of bars being spaced at a distance at least slightly longer than said first distance;
46. a second pair of controlled-pathway propulsion means mounted in parallel, spaced relationship immediately adjacent to and parallel to said first pair of controlled-pathway propulsion means, each of said second pair of controlled-pathway propulsion means having:
47. a second plurality of vertical lift pick-up bars carried by said second pair of controlled-pathway propulsion means and spanning the distance therebetween in a direction at least generally perpendicular to the entry legs of said second pair of controlled-pathway propulsion means, each one of said second plurality of vertical lift pick-up bars being associated with a corresponding one of said first plurality of vertical lift pick-up bars and spaced therebehind by a second distance, which second distance is less than the length of the shortest car in said unit carrier system, at least one of said first and second pluralities of vertical lift pick-up bars being carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the respective one of said pairs of controlled-pathway propulsion means; and
48. means for driving said first and second pairs of controlled-pathway propulsion means at the same speed, and in the same direction.
49. An elevator subassembly as claimed in claim 13 wherein each of said controlled-pathway propulsion means comprises:
50. a plurality of sprockets mounted on shafts extending exteriorly of the space in which said cars are moved, said sprockets being mounted so as to define the juncture of the previously recited legs of said controlled-pathway propulsion means, and
51. an endless chain passing over said plurality of sprockets and being of a length which is the same integral multiple of the distance by which said vertical lift pick-up bars are spaced.
52. Elevator apparatus as claimed in claim 13 wherein both of said first pair of controlled-pathway propulsion means are mounted either interiorly or exteriorly of the adjacent one of said second pair of controlled-pathway propulsion means.
53. In elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said elevator apparatus comprising first and second pluralities of vertical pick-up bars which are moved so that each car is picked up at a car stopping point by one bar from each of said pluralities of bars and carried to another level and each of said cars having first and second lodgment means for one bar from each of said pluralities of bars respectively and an engagement surface located on the exterior thereof in a predetermined relationship to said first lodgment means, an infeed subassembly comprising means for positioning a car stopped at said stopping point to receive one of said first plurality of vertical pick-up bars in said first lodgment means, said means comprising:
54. a movable member having means for releasably engaging said engagement surface on one of said cars when said car is stopped at said stopping point, said movable member being movable between a first position in which it engages said engagement surface on said car while said car is at said stopping point and a second position in which it releases the engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means; and
55. means for synchronizing the motion of said movable member with the motion of said first plurality of vertical lift pick-up bars such that said movable member is moved from its first to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controled-pathway propulsion means adjacent to said stopping point.
56. An infeed subassembly as claimed in claim 16 wherein:
57. said movable member is pivotably mounted at a central point, has means for releasably engaging said engagement surfaces on one side of said central point, and has a partial sprocket on the other side of said central point and
58. said means for synchronizing comprises a sprocket-mounted endless chain which, over a portion of its length, is a double chain, the doubling chain thereof being positioned to engage the partial sprocket on said movable member, thereby causing said movable member to be pivoted from its first position to its second position every time the doubling chain comes into engagement with the partial sprocket, said sprocket-mounted endless chain being driven at a rate such that the doubling chain comes into engagement with the partial sprocket one time for every time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
59. Elevator apparatus as claimed in claim 16 wherein:
60. said movable member is pivotably mounted at a central point and has means for releasably engaging said engagement surfaces on one side of said central point and
61. said means for synchronizing comprise:
62. Elevator apparatus as claimed in claim 16 wherein:
63. said movable member is pivotably mounted about a fixed point at one end thereof and has means for releasably engaging said engagement surfaces at the other end thereof and
64. said means for synchronizing comprise:
65. Elevator apparatus as claimed in claim 19 wherein said means for pivoting said movable member comprises:
66. a sprocket-mounted chain one end of which is connected to said movable member at a point remote from said fixed point;
67. a rod one end of which is connected to the other end of said sprocket-mounted chain;
68. means for causing said rod to be moved in a direction causing said sprocket-mounted chain to be passed around its mounting sprocket one time for every time one of said first plurality of pick-up bars approach the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said movable member to be pivoted from its first position to its second position.
69. Elevator apparatus as claimed in claim 16 wherein said movable member is connected to a shock absorber for absorbing some or all of the impact shock when said engagement surface comes into contact with said movable member.
70. In elevator apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, said elevator apparatus comprising first and second pluralities of vertical lift pick-up bars which are moved so that each car is picked up at a car stopping point by one bar from each of said pluralities of bars and carried to another level and each of said cars having first and second lodgment means for one bar for each of said pluralities of bars respectively and an engagement surface located on the exterior thereof in a predetermined relationship to said first lodgment means, an infeed subassembly comprising means for positioning a car stopped at said stopping point to receive one of said first plurality of vertical lift pick-up bars in said first lodgment means, said means comprising:
71. a first movable member pivotably connected to a second movable member to be recited and movable between a first position in which it engages said engagement surface on a car stopped at said stopping point and a second position in which it releases said engagement surface on said car after having moved said car toward or into a position wherein one of said first plurality of vertical lift pick-up bars will lodge in said first lodgment means;
72. a second movable member, said movable member being movable between a first position in which said first movable member connected thereto is in position to engage the engagement surface on a car stopped at said stopping point and a second position in which said first movable member connected thereto is in its second position; and
73. means for synchronizing the motion of said second movable member with the motion of said first plurality of vertical lift pick-up bars such that said second movable member is moved from its first position to its second position one time for every time one of said first plurality of vertical lift pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point, thereby causing said car to be moved into position to be picked up by one of said first plurality of vertical lift pick-up bars at the proper time.
74. An infeed subassembly as claimed in claim 22 wherein:
75. said second movable member is pivoted about a central point and
76. said means for synchronizing comprise a sprocket-mounted endless chain bearing means for causing the pivoting of said second movable member from its first position to its second position about said central point one time for every one time one of said first plurality of vertical pick-up bars approaches the ends of the entry legs of said first pair of controlled-pathway propulsion means adjacent to said stopping point.
Description:
FIELD OF THE INVENTION
This invention relates generally to apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, and, more specifically, to apparatus for changing the elevation of cars in a unit carrier system such as is disclosed in commonly assigned U.S. Pat. Nos. 3,621,790, 3,626,859, and 3,650,216.
BACKGROUND OF THE INVENTION
In unit carrier systems such as are disclosed in the above-listed patents, it is sometimes necessary to move the cars from one level to another in a confined space, precluding the use of inclined paths and supplementary drive apparatus such as is disclosed in commonly assigned U.S. Pat. application No. 315,694, filed Dec. 15, 1972. In such situations, elevator apparatus must be used to move the cars from one level to another. The design of such apparatus, however, presents various problems where it is desired to move a relatively large number of cars per unit time while maintaining the cars in horizontal position. This is particularly true because, in such systems, it is almost necessary to keep the cars in linear order -- i.e., it is quite impractical to bunch a plurality of them up in a two dimensional array on the floor of a single large elevator. Accordingly, it is highly desirable that such elevator apparatus should be capable of acting on a plurality of cars at once while keeping those cars in linear order and that the operation of the elevator be uni-directional -- i.e., without loss of time as lifting apparatus is repositioned for subsequent loads.
SUMMARY OF THE INVENTION
The present invention is designed to accomplish the above object in an inexpensive but highly reliable fashion. Speaking broadly, the overall elevator apparatus comprises an elevator subassembly and an infeed subassembly. The former comprises two pairs of controlled-pathway propulsion means each of which carries a plurality of vertical lift pick-up bars therebetween in a manner permitting the cars of the unit carrier system to be picked up by two bars, one associated with each pair of controlled-pathway propulsion means, and carried from one level to another thereby. The latter comprises a movable member having means for releasably engaging a suitable surface on each car and synchronizing means adapted to cause the movable member to propel the car into position to be picked up by the pick-up bars at or before the time the bars come into position to pick up the cars.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of the present invention having four two-bar elevating units.
FIG. 2 is a partial section generally along the lines 2--2 in FIG. 1.
FIG. 3 is a partial side view along the lines 3--3 in FIG. 1.
FIG. 4 is a partial section generally along the lines 4--4 in FIG. 1.
FIGS. 5-8 are a series of schematic side views illustrating the sequence of events during the operation of the preferred embodiment of the present invention.
FIGS. 9-12 are side views of alternative embodiments of the infeed subassembly the preferred form of which is shown in FIG. 3.
DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS
The present invention will be illustrated by means of detailed descriptions of embodiments thereof particularly adapted to lift cars up from one level to a higher level. It will be apparent to those skilled in the art, however, that these embodiments could be readily modified to carry cars down from one level to a lower level, or even to carry cars in either direction.
The present invention comprises four controlled-pathway propulsion means 20, 22, 24, 26. In the preferred embodiment shown in FIGS. 1-4, each of the controlled-pathway propulsion means 20, 22, 24, 26 comprises a plurality of sprockets 28 mounted on shafts 30 extending exteriorly of the space in which the cars 32 are moved. As may be seen in FIG. 1, the four controlled-pathway propulsion means 20, 22, 24, 26 are mounted in pairs, a first pair consisting of means 22 and 26 and a second pair consisting of means 20 and 24. The first pair of controlled-pathway propulsion means 22, 26 are mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in the unit carrier system, and the second pair of controlled-pathway propulsion means 20, 24 are mounted in parallel, spaced relationship immediately adjacent to and parallel to the first pair. Preferably, but not necessarily, both members of one of the two pairs are mounted interiorly of both members of the other pair.
Four of the sprockets 28 define entry legs 34, intermediate legs 36, and exit legs 38 in each of the four controlled-pathway propulsion means. The entry legs 34 are located parallel to or in the same plane as a path 40 for the cars 32 of the carrier system, and they extend generally in the same direction as the path 40 at that point in order to facilitate entry into the elevator. The exit legs 38 are located parallel to or in the same plane as a path 42 for the cars 32 of the carrier system, and they similarly extend generally in the same direction as the path 42 at that point in order to facilitate exit from the elevator. The intermediate legs 36 connect the entry and exit legs, but it will at once be appreciated that they need not be vertical, as shown, or even straight. In fact, what is here termed "the" intermediate legs 36 may be composed of a plurality of separately identifiable legs moving the cars 32 in different directions during the course of their overall movement from the entry legs 34 to the exit legs 38.
The length of the entry leg 34 in the first pair of controlled-pathway propulsion means 22, 26 is at least slightly longer than the length of the longest car 32 in the unit carrier system in order to allow each car 32 to be drawn completely into the elevator apparatus (by means to be disclosed hereinafter) before the car is begun to be carried along the path of the intermediate leg 36. For similar reasons, the length of the exit leg 38 of the second pair of controlled-pathway propulsion means 20, 24 is at least slightly longer than the length of the longest car 32 in the unit carrier system. While it is convenient, when using the sprocket-and-chain embodiment shown in FIG. 1, to mount the sprocket 28 initiating the entry leg 34 of the second pair of controlled-pathway propulsion means 20, 24 on the same shaft 30 on which the sprocket 28 initiating the entry leg 34 of the first pair of controlled-pathway propulsion means 22, 26 is mounted, it will be appreciated that the former could be mounted on a separate shaft, since the exact point at which the cars 32 are engaged by the second pair of controlled-pathway propulsion means 20, 24 is arbitrary, so long as the cars are engaged by both pairs prior to the time the propulsion means begin to carry the cars from one level to another.
A first plurality of vertical lift pick-up bars 44 are carried by the first pair of controlled-pathway propulsion means 22, 26 in a manner spanning the distance therebetween in a direction at least generally perpendicular to the entry legs 34 thereof, and a second plurality of vertical lift pick-up bars 46 are carried by the second pair of controlled-pathway propulsion means 20, 24 in a manner spanning the distance therebetween in a direction at least generally perpendicular to the entry legs 34 thereof. The first plurality of bars 44 are spaced at a distance at least slightly longer than the length of the longest car 32 in the unit carrier system, and each of the second plurality of bars 46 is associated with one of the first plurality of bars 44 and spaced therebehind by a distance which is less than the length of the shortest car 32 in the unit carrier system. The overall length of each controlled-pathway propulsion means 20, 22, 24, 26 is equal to the overall length of every other controlled-pathway propulsion means 20, 22, 24, 26, and the length of each one is preferabe equal to an integral multiple of the distance by which the vertical lift pick-up bars 44, 46 are spaced. Satisfaction of the latter condition provides a regular flow pattern through the elevator, but it is clearly not essential to the operation of the apparatus.
Since the vertical lift pick-up bars 44, 46 are carried in controlled, spaced relationship, they do not interfere with each other, and gaps 47 may easily be provided in the entry path 40 and the exit path 42, if it is desired that they extend somewhat into the elevator subassembly as shown in FIG. 1, in order to permit the vertical lift pick-up bars to pass therethrough. However, in order to ensure that each plurality of vertical lift pick-up bars 44, 46 does not interfere with the controlled-pathway propulsion means carrying the other plurality thereof, any plurality which crosses over a controlled-pathway propulsion means must be carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the controlled-pathway propulsion means crossed to the associated controlled-pathway propulsion means. In the embodiment shown in FIG. 1, wherein both of the first pair of controlled-pathway propulsion means 22, 26 are mounted interiorly of both of the second pair of controlled-pathway propulsion means 20, 24, this means that the second plurality of vertical lift pick-up bars 46 must be carried by the second pair of controlled-pathway propulsion means 20, 24 at a level at least slightly outside the plane connecting the first pair of controlled-pathway propulsion means 22, 26. While FIG. 1 shows the first plurality of vertical lift pick-up bars 44 carried by the first pair of controlled-pathway propulsion means 22, 26 in similar fashion, it will be appreciated that this is unnecessary and is done merely to standardize the mounting brackets 48, which are best seen in FIG. 4.
Means for driving the first and second pairs of controlled-pathway propulsion means at the same speed and in the same direction must be provided, but, as any appropriate means, many of which are already known, may be used and as which means is used forms no part of this invention, drive means 50 are shown only schematically in FIG. 1.
The cars 32 may be of any type, the one shown in FIG. 1 being generally of the type disclosed in commonly assigned U.S. utility Pat. No. 3,572,253 and U.S. design Pat. No. 223,516. Means must be provided for stopping the cars 32 at a stopping point immediately prior to the elevator apparatus on the path 40, but, as such stopping means form no part of the present invention, they are not depicted in the drawing or described further herein. It is noted, however, that two different apparatuses which may be used as stopping means herewith are disclosed in commonly assigned U.S. Pat. applications 309,026 and 309,373, both filed on Nov. 24, 1972.
The cars 32 have first lodgment means 52 adapted to receive one of the first plurality of vertical lift pick-up bars 44 located on their undersides close to their front ends and second lodgment means 54 adapted to receive one of the second plurality of vertical lift pick-up bars 46 located on their undersides a distance back from the first lodgment means 52 equal to the distance between each of the first plurality of vertical lift pick-up bars 44 and the associated one of the second plurality of vertical lift pick-up bars 46. In the embodiment shown in FIG. 1, the car 32 is adapted to be fed into the elevator apparatus in either direction, and it accordingly has a first lodgment means 52 at either end and a second lodgment means 54 located interiorly thereof by the above-mentioned distance. Before continuing, it should be pointed out that when it is stated that the first lodgment means 52 is located "close" to the front end of the cars 32, this is a very relative term, and all that is really necessary is that the two lodgment means used at one time be located sufficiently far on either side of the center of gravity of the car 32 under any possible load conditions so that the car 32 will remain stable in a horizontal position while being carried by vertical lift pick-up bars lodged in the two lodgment means. It is only desirable that the first lodgment means 52 be located relatively close to the front end of the cars 32 so that the portion of the cars 32 extending in front of the first lodgment means 52 will not interfere with the one of the second plurality of vertical lift pick-up bars 46 preceding the one of the first plurality of vertical lift pick-up bars 44 which ultimately engages the first lodgment means 52 in an embodiment such as that shown in FIG. 1, wherein the initiation point of the entry leg 34 of the second pair of controlled-pathway propulsions means 20, 24 is at or upstream of the initiation point of the entry leg 34 of the first pair of controlled-pathway propulsion means 22, 26 and the second plurality of vertical lift pick-up bars 46 are carried in the entry leg at a height at least as high as the underside of the car 32 in front of the first lodgment means 52.
In order to bring each car 32 from the previously mentioned stopping point (provided by means not a part of this invention) into a position such that one of the first plurality of vertical lift pick-up bars 44 will lodge in its first lodgment means 52, appropriate positioning means denominated generally by the numeral 56 must be provided. These means may be as simple as a downward tilt to the path 40 immediately prior to the elevator apparatus coupled with a releasable detent mechanism of any appropriate type synchronously controlled by the first pair of controlled-pathway propulsion means 20, 24. However, a positive engagement and in-feed apparatus is generally preferably for a high-speed system such as the present invention is particularly suited for, and a variety of such apparatuses are shown in the accompanying figures.
All of the in-feed apparatus shown in the accompanying figures employ a projection 58 located on at least one side of the car 32. In the system in which we employ this invention, the projection 58 may be the cam follower 28 disclosed in commonly assigned U.S. Pat. No. 3,613,916, but, obviously, it may be a projection adapted solely for this purpose, or for this purpose and any other appropriate purpose. Similarly, the projection 58 is just a specific type of engagement surface, and the same results could be obtained by use of any other appropriate engagement surface, including the back of the car 32. All that is really necessary is that the projection 58 or the equivalent engagement surface be located on each car 32 in a predetermined relationship to the first lodgment means 52.
In the preferred embodiment of the infeed apparatus, shown in FIGS. 1-3, the projection 58 is releasably engaged by a movable member 60 which is pivotable about a shaft 62 from a first position in which it engages the projection 58 while the car 32 is at its stopping point to a second position in which it releases the projection 58 after having moved the car 32 toward or into a position wherein one of the first plurality of vertical lift pick-up bars 44 will lodge in the first lodgment means 52. The releasable engagement of the projection 58 is provided by the cooperation of a ratchet mechanism 64 (the interior mechanism of which is illustrated only in FIG. 10) and a fixed contact surface 66. As a car 32 comes into position, it forces exterior projection 68 of the ratchet mechanism 64 to pivot about its pivot 70 against the spring 72, permitting the projection 58 to come into contact with, and be completely stopped by, the fixed contact surface 66. (It will be appreciated that the fixed contact surface 66 only supplements the previously mentioned stopping means, and in some embodiments it may be found desirable to omit it altogether.) After the projection 58 has passed over the projection 68, the spring 72 causes the latter to rotate back to its stable position against the stop 74, in which position the movable member 60 is ready to drive the car 32 into position to be picked up by the elevator subassembly.
The motion of the movable member 60 may be synchronized with the motion of the first plurality of vertical lift pick-up bars 44 by any one of a large number of different means. However, the synchronous control means depicted in FIGs. 1-3 have proved to be exceptionally sturdy, inexpensive to manufacture, and of perfectly acceptable accuracy. This means comprises a partial sprocket 76 on the movable member 60, located on the other side of the shaft 62 from the ratchet mechanism 64. An endless chain 78 is mounted on sprockets 80 adjacent to the movable member 60, and over a portion of the length of the endless chain 78 a doubling chain 82 is attached thereto. The sprockets 80 are so mounted that the doubling chain 82 engages the partial sprocket 76 every time the doubling chain 82 reaches that point on the path of the endless chain 78. The engagement of the doubling chain 82 with the partial sprocket 76 causes the latter to pivot about the shaft 62, driving the car 32 forward towards or into position to be picked up by one of the first plurality of vertical lift pick-up bars 44. After the doubling chain 82 has passed out of engagement with the partial sprocket 76, the spring 84 causes the movable member 60 to pivot back into its first position.
In the embodiment shown in FIGS. 1-3, the endless chain 78 is the same length as the distance between the bars in the first plurality of vertical lift pick-up bars 44, and it is driven at the same speed as the first pair of controlled pathway propulsion means 22, 26 by means of an idler chain 86. However, it will be appreciated that the chain 78 could be driven either more rapidly or more slowly than the propulsion means 22, 26, depending on the speed with which it was desired to drive the cars 32 forward towards their engagement with the vertical lift pick-up bars 44, and that the idler chain 86 could be dispensed with entirely, depending on the relative positioning of the left-hand sprocket 28 in FIG. 3 and the movable member 60.
The various alternative embodiments of the infeed subassembly shown in FIGS. 9-12 will now be briefly described, omitting redescription of those portions which are the same as the previously described embodiment shown in FIGS. 1-3.
In FIG. 9, a first rod 88 is pivotably connected to the side of the movable member 60 opposite to the side having the means for releasabably engaging the projections 58. The other end of the first rod 88 is pivotably connected to one end of a second rod 90 and the other end of the second rod 90 is pivotably mounted about a fixed point. The end of the rod 90 connected to the rod 88 is positioned so that the rod 90 is forced to pivot by contact with each of the first plurality of vertical lift pick-up bars 44, and the motion of the rod 90 is transmitted through the rod 88 to the movable member 90, causing it to rotate about the shaft 62 in the same manner as previously described. A spring 92 can be provided at any appropriate point in the linkage to cause it to return to its first position inbetween operations.
In FIG. 10, the movable member 60 is pivotably mounted about the shaft 62 as before, but the movable member 60 is pivoted by means of a linkage attached thereto at a point 94 between the shaft 62 and the means for releasably engaging the projections 58. The point 94 is connected to a sprocket-mounted chain 96 the other end of which is connected to a rod 98, which is preferably, but not necessarily, journaled in bearings (not shown) confining it to translational motion. The other end of the rod 98 is positioned to be moved directly or indirectly by each of the first plurality of vertical lift pick-up bars 44, ultimately causing the movable member 60 to be pivoted as before.
In FIG. 11, the one-piece movable member 60 is replaced by a plurality of parts which, taken together perform the same general function. The movable stop member 100 replaces the fixed contact surface 66, but because of the slot 102 permitting it to move with respect to the shaft 104 mounted on the sliding member 106, the motion of which in response to contact by a car 32 is resisted by the spring 108, the movable stop member 100 can help to provide a smoothly graduated deceleration, which the fixed contact surface 66 does not. The first movable member 110 replaces the ratchet mechanism 64 and performs the same function. The second movable member 112 replaces the balance of the movable member 60, and it may be rotated about the shaft 62 by a suitable projection (not shown) carried on the endless chain 114, which then perform the same function as the endless chain 78. However, the shaft 62 and the entire structure 116 carrying the movable stop member 100, the sliding member 106, and the first movable member 110 are connected to a shock absorber 118 for absorbing some or all of the impact shock when the projection 58 comes into contact with the movable stop member 100.
FIG. 12 shows additional structure generally similar to the structural already described except that the pivoting of the second movable member 112 about the shaft 62 is caused by a two-way fluid cylinder 120, the operation of which is controlled by a synchronous control means 122 which may be, for instance, an electric eye to detect passage of one of the first plurality of vertical lift pick-up bars 44 and appropriate time-delay circuitry to move the second movable member 112 back and forth between its first and second positions at suitable intervals.
OPERATION OF THE SYSTEM
Having now described the components of the elevator apparatus in some detail, we will now describe its operation briefly with the aid of FIGS. 5-8.
In FIG. 5, a first car 32 is shown leaving the elevator apparatus, a second car 32 is shown being lifted by the elevator apparatus, and third and fourth cars 32 are shown approaching the elevator apparatus. In FIG. 6, the first car 32 has left the apparatus, the second car 32 is approaching the top of the elevator subassembly, the third car 32 has some to a stop and is releasably engaged by the movable member 60, and the fourth car 32 is still approaching the elevator apparatus. In FIG. 7, the second car 32 is almost to the top of the elevator subassembly, the movable member 60 has been pivoted, driving the third car 32 forward, one of the first plurality of vertical lift pick-up bars 44 has engaged the first lodgment means 52 on the third car 32 and is drawing the third car 32 forward into the elevator subassembly, and the fourth car 32 is still approaching the elevator apparatus. In FIG. 8, the second car 32 is moving horizontally on the exit legs 38 of the controlled pathway propulsion means 20, 22, 24, 26, the third car 32 is moving horizontally on the entry legs 34 of the controlled pathway propulsions means 20, 22, 24, 26, and the fourth car 32 has come to a stop and is releasably engaged by the movable member 60. Obviously, these operations can be continued cyclically at high speeds over prolonged periods of time, thereby accomplishing the objects of this invention.
CAVEAT
While the present invention has been illustrated by detailed descriptions of preferred embodiments thereof, it will be obvious to those skilled in the art that various changes in form and detail can be made therein without departing from the true scope of the invention. For that reasons, the invention must be measured by the claims appended hereto and not by the foregoing preferred embodiments.
This invention relates generally to apparatus for moving from one level to another the cars of a unit carrier system having a plurality of cars which travel along predetermined paths, and, more specifically, to apparatus for changing the elevation of cars in a unit carrier system such as is disclosed in commonly assigned U.S. Pat. Nos. 3,621,790, 3,626,859, and 3,650,216.
BACKGROUND OF THE INVENTION
In unit carrier systems such as are disclosed in the above-listed patents, it is sometimes necessary to move the cars from one level to another in a confined space, precluding the use of inclined paths and supplementary drive apparatus such as is disclosed in commonly assigned U.S. Pat. application No. 315,694, filed Dec. 15, 1972. In such situations, elevator apparatus must be used to move the cars from one level to another. The design of such apparatus, however, presents various problems where it is desired to move a relatively large number of cars per unit time while maintaining the cars in horizontal position. This is particularly true because, in such systems, it is almost necessary to keep the cars in linear order -- i.e., it is quite impractical to bunch a plurality of them up in a two dimensional array on the floor of a single large elevator. Accordingly, it is highly desirable that such elevator apparatus should be capable of acting on a plurality of cars at once while keeping those cars in linear order and that the operation of the elevator be uni-directional -- i.e., without loss of time as lifting apparatus is repositioned for subsequent loads.
SUMMARY OF THE INVENTION
The present invention is designed to accomplish the above object in an inexpensive but highly reliable fashion. Speaking broadly, the overall elevator apparatus comprises an elevator subassembly and an infeed subassembly. The former comprises two pairs of controlled-pathway propulsion means each of which carries a plurality of vertical lift pick-up bars therebetween in a manner permitting the cars of the unit carrier system to be picked up by two bars, one associated with each pair of controlled-pathway propulsion means, and carried from one level to another thereby. The latter comprises a movable member having means for releasably engaging a suitable surface on each car and synchronizing means adapted to cause the movable member to propel the car into position to be picked up by the pick-up bars at or before the time the bars come into position to pick up the cars.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of the present invention having four two-bar elevating units.
FIG. 2 is a partial section generally along the lines 2--2 in FIG. 1.
FIG. 3 is a partial side view along the lines 3--3 in FIG. 1.
FIG. 4 is a partial section generally along the lines 4--4 in FIG. 1.
FIGS. 5-8 are a series of schematic side views illustrating the sequence of events during the operation of the preferred embodiment of the present invention.
FIGS. 9-12 are side views of alternative embodiments of the infeed subassembly the preferred form of which is shown in FIG. 3.
DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS
The present invention will be illustrated by means of detailed descriptions of embodiments thereof particularly adapted to lift cars up from one level to a higher level. It will be apparent to those skilled in the art, however, that these embodiments could be readily modified to carry cars down from one level to a lower level, or even to carry cars in either direction.
The present invention comprises four controlled-pathway propulsion means 20, 22, 24, 26. In the preferred embodiment shown in FIGS. 1-4, each of the controlled-pathway propulsion means 20, 22, 24, 26 comprises a plurality of sprockets 28 mounted on shafts 30 extending exteriorly of the space in which the cars 32 are moved. As may be seen in FIG. 1, the four controlled-pathway propulsion means 20, 22, 24, 26 are mounted in pairs, a first pair consisting of means 22 and 26 and a second pair consisting of means 20 and 24. The first pair of controlled-pathway propulsion means 22, 26 are mounted in parallel, spaced relationship a distance apart slightly in excess of the width of the broadest car in the unit carrier system, and the second pair of controlled-pathway propulsion means 20, 24 are mounted in parallel, spaced relationship immediately adjacent to and parallel to the first pair. Preferably, but not necessarily, both members of one of the two pairs are mounted interiorly of both members of the other pair.
Four of the sprockets 28 define entry legs 34, intermediate legs 36, and exit legs 38 in each of the four controlled-pathway propulsion means. The entry legs 34 are located parallel to or in the same plane as a path 40 for the cars 32 of the carrier system, and they extend generally in the same direction as the path 40 at that point in order to facilitate entry into the elevator. The exit legs 38 are located parallel to or in the same plane as a path 42 for the cars 32 of the carrier system, and they similarly extend generally in the same direction as the path 42 at that point in order to facilitate exit from the elevator. The intermediate legs 36 connect the entry and exit legs, but it will at once be appreciated that they need not be vertical, as shown, or even straight. In fact, what is here termed "the" intermediate legs 36 may be composed of a plurality of separately identifiable legs moving the cars 32 in different directions during the course of their overall movement from the entry legs 34 to the exit legs 38.
The length of the entry leg 34 in the first pair of controlled-pathway propulsion means 22, 26 is at least slightly longer than the length of the longest car 32 in the unit carrier system in order to allow each car 32 to be drawn completely into the elevator apparatus (by means to be disclosed hereinafter) before the car is begun to be carried along the path of the intermediate leg 36. For similar reasons, the length of the exit leg 38 of the second pair of controlled-pathway propulsion means 20, 24 is at least slightly longer than the length of the longest car 32 in the unit carrier system. While it is convenient, when using the sprocket-and-chain embodiment shown in FIG. 1, to mount the sprocket 28 initiating the entry leg 34 of the second pair of controlled-pathway propulsion means 20, 24 on the same shaft 30 on which the sprocket 28 initiating the entry leg 34 of the first pair of controlled-pathway propulsion means 22, 26 is mounted, it will be appreciated that the former could be mounted on a separate shaft, since the exact point at which the cars 32 are engaged by the second pair of controlled-pathway propulsion means 20, 24 is arbitrary, so long as the cars are engaged by both pairs prior to the time the propulsion means begin to carry the cars from one level to another.
A first plurality of vertical lift pick-up bars 44 are carried by the first pair of controlled-pathway propulsion means 22, 26 in a manner spanning the distance therebetween in a direction at least generally perpendicular to the entry legs 34 thereof, and a second plurality of vertical lift pick-up bars 46 are carried by the second pair of controlled-pathway propulsion means 20, 24 in a manner spanning the distance therebetween in a direction at least generally perpendicular to the entry legs 34 thereof. The first plurality of bars 44 are spaced at a distance at least slightly longer than the length of the longest car 32 in the unit carrier system, and each of the second plurality of bars 46 is associated with one of the first plurality of bars 44 and spaced therebehind by a distance which is less than the length of the shortest car 32 in the unit carrier system. The overall length of each controlled-pathway propulsion means 20, 22, 24, 26 is equal to the overall length of every other controlled-pathway propulsion means 20, 22, 24, 26, and the length of each one is preferabe equal to an integral multiple of the distance by which the vertical lift pick-up bars 44, 46 are spaced. Satisfaction of the latter condition provides a regular flow pattern through the elevator, but it is clearly not essential to the operation of the apparatus.
Since the vertical lift pick-up bars 44, 46 are carried in controlled, spaced relationship, they do not interfere with each other, and gaps 47 may easily be provided in the entry path 40 and the exit path 42, if it is desired that they extend somewhat into the elevator subassembly as shown in FIG. 1, in order to permit the vertical lift pick-up bars to pass therethrough. However, in order to ensure that each plurality of vertical lift pick-up bars 44, 46 does not interfere with the controlled-pathway propulsion means carrying the other plurality thereof, any plurality which crosses over a controlled-pathway propulsion means must be carried by its associated controlled-pathway propulsion means at a level at least slightly outside the plane connecting the controlled-pathway propulsion means crossed to the associated controlled-pathway propulsion means. In the embodiment shown in FIG. 1, wherein both of the first pair of controlled-pathway propulsion means 22, 26 are mounted interiorly of both of the second pair of controlled-pathway propulsion means 20, 24, this means that the second plurality of vertical lift pick-up bars 46 must be carried by the second pair of controlled-pathway propulsion means 20, 24 at a level at least slightly outside the plane connecting the first pair of controlled-pathway propulsion means 22, 26. While FIG. 1 shows the first plurality of vertical lift pick-up bars 44 carried by the first pair of controlled-pathway propulsion means 22, 26 in similar fashion, it will be appreciated that this is unnecessary and is done merely to standardize the mounting brackets 48, which are best seen in FIG. 4.
Means for driving the first and second pairs of controlled-pathway propulsion means at the same speed and in the same direction must be provided, but, as any appropriate means, many of which are already known, may be used and as which means is used forms no part of this invention, drive means 50 are shown only schematically in FIG. 1.
The cars 32 may be of any type, the one shown in FIG. 1 being generally of the type disclosed in commonly assigned U.S. utility Pat. No. 3,572,253 and U.S. design Pat. No. 223,516. Means must be provided for stopping the cars 32 at a stopping point immediately prior to the elevator apparatus on the path 40, but, as such stopping means form no part of the present invention, they are not depicted in the drawing or described further herein. It is noted, however, that two different apparatuses which may be used as stopping means herewith are disclosed in commonly assigned U.S. Pat. applications 309,026 and 309,373, both filed on Nov. 24, 1972.
The cars 32 have first lodgment means 52 adapted to receive one of the first plurality of vertical lift pick-up bars 44 located on their undersides close to their front ends and second lodgment means 54 adapted to receive one of the second plurality of vertical lift pick-up bars 46 located on their undersides a distance back from the first lodgment means 52 equal to the distance between each of the first plurality of vertical lift pick-up bars 44 and the associated one of the second plurality of vertical lift pick-up bars 46. In the embodiment shown in FIG. 1, the car 32 is adapted to be fed into the elevator apparatus in either direction, and it accordingly has a first lodgment means 52 at either end and a second lodgment means 54 located interiorly thereof by the above-mentioned distance. Before continuing, it should be pointed out that when it is stated that the first lodgment means 52 is located "close" to the front end of the cars 32, this is a very relative term, and all that is really necessary is that the two lodgment means used at one time be located sufficiently far on either side of the center of gravity of the car 32 under any possible load conditions so that the car 32 will remain stable in a horizontal position while being carried by vertical lift pick-up bars lodged in the two lodgment means. It is only desirable that the first lodgment means 52 be located relatively close to the front end of the cars 32 so that the portion of the cars 32 extending in front of the first lodgment means 52 will not interfere with the one of the second plurality of vertical lift pick-up bars 46 preceding the one of the first plurality of vertical lift pick-up bars 44 which ultimately engages the first lodgment means 52 in an embodiment such as that shown in FIG. 1, wherein the initiation point of the entry leg 34 of the second pair of controlled-pathway propulsions means 20, 24 is at or upstream of the initiation point of the entry leg 34 of the first pair of controlled-pathway propulsion means 22, 26 and the second plurality of vertical lift pick-up bars 46 are carried in the entry leg at a height at least as high as the underside of the car 32 in front of the first lodgment means 52.
In order to bring each car 32 from the previously mentioned stopping point (provided by means not a part of this invention) into a position such that one of the first plurality of vertical lift pick-up bars 44 will lodge in its first lodgment means 52, appropriate positioning means denominated generally by the numeral 56 must be provided. These means may be as simple as a downward tilt to the path 40 immediately prior to the elevator apparatus coupled with a releasable detent mechanism of any appropriate type synchronously controlled by the first pair of controlled-pathway propulsion means 20, 24. However, a positive engagement and in-feed apparatus is generally preferably for a high-speed system such as the present invention is particularly suited for, and a variety of such apparatuses are shown in the accompanying figures.
All of the in-feed apparatus shown in the accompanying figures employ a projection 58 located on at least one side of the car 32. In the system in which we employ this invention, the projection 58 may be the cam follower 28 disclosed in commonly assigned U.S. Pat. No. 3,613,916, but, obviously, it may be a projection adapted solely for this purpose, or for this purpose and any other appropriate purpose. Similarly, the projection 58 is just a specific type of engagement surface, and the same results could be obtained by use of any other appropriate engagement surface, including the back of the car 32. All that is really necessary is that the projection 58 or the equivalent engagement surface be located on each car 32 in a predetermined relationship to the first lodgment means 52.
In the preferred embodiment of the infeed apparatus, shown in FIGS. 1-3, the projection 58 is releasably engaged by a movable member 60 which is pivotable about a shaft 62 from a first position in which it engages the projection 58 while the car 32 is at its stopping point to a second position in which it releases the projection 58 after having moved the car 32 toward or into a position wherein one of the first plurality of vertical lift pick-up bars 44 will lodge in the first lodgment means 52. The releasable engagement of the projection 58 is provided by the cooperation of a ratchet mechanism 64 (the interior mechanism of which is illustrated only in FIG. 10) and a fixed contact surface 66. As a car 32 comes into position, it forces exterior projection 68 of the ratchet mechanism 64 to pivot about its pivot 70 against the spring 72, permitting the projection 58 to come into contact with, and be completely stopped by, the fixed contact surface 66. (It will be appreciated that the fixed contact surface 66 only supplements the previously mentioned stopping means, and in some embodiments it may be found desirable to omit it altogether.) After the projection 58 has passed over the projection 68, the spring 72 causes the latter to rotate back to its stable position against the stop 74, in which position the movable member 60 is ready to drive the car 32 into position to be picked up by the elevator subassembly.
The motion of the movable member 60 may be synchronized with the motion of the first plurality of vertical lift pick-up bars 44 by any one of a large number of different means. However, the synchronous control means depicted in FIGs. 1-3 have proved to be exceptionally sturdy, inexpensive to manufacture, and of perfectly acceptable accuracy. This means comprises a partial sprocket 76 on the movable member 60, located on the other side of the shaft 62 from the ratchet mechanism 64. An endless chain 78 is mounted on sprockets 80 adjacent to the movable member 60, and over a portion of the length of the endless chain 78 a doubling chain 82 is attached thereto. The sprockets 80 are so mounted that the doubling chain 82 engages the partial sprocket 76 every time the doubling chain 82 reaches that point on the path of the endless chain 78. The engagement of the doubling chain 82 with the partial sprocket 76 causes the latter to pivot about the shaft 62, driving the car 32 forward towards or into position to be picked up by one of the first plurality of vertical lift pick-up bars 44. After the doubling chain 82 has passed out of engagement with the partial sprocket 76, the spring 84 causes the movable member 60 to pivot back into its first position.
In the embodiment shown in FIGS. 1-3, the endless chain 78 is the same length as the distance between the bars in the first plurality of vertical lift pick-up bars 44, and it is driven at the same speed as the first pair of controlled pathway propulsion means 22, 26 by means of an idler chain 86. However, it will be appreciated that the chain 78 could be driven either more rapidly or more slowly than the propulsion means 22, 26, depending on the speed with which it was desired to drive the cars 32 forward towards their engagement with the vertical lift pick-up bars 44, and that the idler chain 86 could be dispensed with entirely, depending on the relative positioning of the left-hand sprocket 28 in FIG. 3 and the movable member 60.
The various alternative embodiments of the infeed subassembly shown in FIGS. 9-12 will now be briefly described, omitting redescription of those portions which are the same as the previously described embodiment shown in FIGS. 1-3.
In FIG. 9, a first rod 88 is pivotably connected to the side of the movable member 60 opposite to the side having the means for releasabably engaging the projections 58. The other end of the first rod 88 is pivotably connected to one end of a second rod 90 and the other end of the second rod 90 is pivotably mounted about a fixed point. The end of the rod 90 connected to the rod 88 is positioned so that the rod 90 is forced to pivot by contact with each of the first plurality of vertical lift pick-up bars 44, and the motion of the rod 90 is transmitted through the rod 88 to the movable member 90, causing it to rotate about the shaft 62 in the same manner as previously described. A spring 92 can be provided at any appropriate point in the linkage to cause it to return to its first position inbetween operations.
In FIG. 10, the movable member 60 is pivotably mounted about the shaft 62 as before, but the movable member 60 is pivoted by means of a linkage attached thereto at a point 94 between the shaft 62 and the means for releasably engaging the projections 58. The point 94 is connected to a sprocket-mounted chain 96 the other end of which is connected to a rod 98, which is preferably, but not necessarily, journaled in bearings (not shown) confining it to translational motion. The other end of the rod 98 is positioned to be moved directly or indirectly by each of the first plurality of vertical lift pick-up bars 44, ultimately causing the movable member 60 to be pivoted as before.
In FIG. 11, the one-piece movable member 60 is replaced by a plurality of parts which, taken together perform the same general function. The movable stop member 100 replaces the fixed contact surface 66, but because of the slot 102 permitting it to move with respect to the shaft 104 mounted on the sliding member 106, the motion of which in response to contact by a car 32 is resisted by the spring 108, the movable stop member 100 can help to provide a smoothly graduated deceleration, which the fixed contact surface 66 does not. The first movable member 110 replaces the ratchet mechanism 64 and performs the same function. The second movable member 112 replaces the balance of the movable member 60, and it may be rotated about the shaft 62 by a suitable projection (not shown) carried on the endless chain 114, which then perform the same function as the endless chain 78. However, the shaft 62 and the entire structure 116 carrying the movable stop member 100, the sliding member 106, and the first movable member 110 are connected to a shock absorber 118 for absorbing some or all of the impact shock when the projection 58 comes into contact with the movable stop member 100.
FIG. 12 shows additional structure generally similar to the structural already described except that the pivoting of the second movable member 112 about the shaft 62 is caused by a two-way fluid cylinder 120, the operation of which is controlled by a synchronous control means 122 which may be, for instance, an electric eye to detect passage of one of the first plurality of vertical lift pick-up bars 44 and appropriate time-delay circuitry to move the second movable member 112 back and forth between its first and second positions at suitable intervals.
OPERATION OF THE SYSTEM
Having now described the components of the elevator apparatus in some detail, we will now describe its operation briefly with the aid of FIGS. 5-8.
In FIG. 5, a first car 32 is shown leaving the elevator apparatus, a second car 32 is shown being lifted by the elevator apparatus, and third and fourth cars 32 are shown approaching the elevator apparatus. In FIG. 6, the first car 32 has left the apparatus, the second car 32 is approaching the top of the elevator subassembly, the third car 32 has some to a stop and is releasably engaged by the movable member 60, and the fourth car 32 is still approaching the elevator apparatus. In FIG. 7, the second car 32 is almost to the top of the elevator subassembly, the movable member 60 has been pivoted, driving the third car 32 forward, one of the first plurality of vertical lift pick-up bars 44 has engaged the first lodgment means 52 on the third car 32 and is drawing the third car 32 forward into the elevator subassembly, and the fourth car 32 is still approaching the elevator apparatus. In FIG. 8, the second car 32 is moving horizontally on the exit legs 38 of the controlled pathway propulsion means 20, 22, 24, 26, the third car 32 is moving horizontally on the entry legs 34 of the controlled pathway propulsions means 20, 22, 24, 26, and the fourth car 32 has come to a stop and is releasably engaged by the movable member 60. Obviously, these operations can be continued cyclically at high speeds over prolonged periods of time, thereby accomplishing the objects of this invention.
CAVEAT
While the present invention has been illustrated by detailed descriptions of preferred embodiments thereof, it will be obvious to those skilled in the art that various changes in form and detail can be made therein without departing from the true scope of the invention. For that reasons, the invention must be measured by the claims appended hereto and not by the foregoing preferred embodiments.