DIE-STABILIZING MECHANISM FOR A SPLIT FLANGING DIE UNIT
United States Patent 3845656
A split flanging die unit--of the type disclosed in U.S. Pat. No. 3,540,260, and as employed to form a continuous out-turned flange on an end of an initially open-ended, cylindrical, sheet metal body for a drum or pail--fitted with a die-stabilizing mechanism arranged to automatically block, by means including bridging members, the die halves (which have a diametral slot therebetween) against undesirable deflection toward each other when the die unit is forcefully advanced (raised) into engagement with the end of the sheet metal body to perform the flanging operation, and, upon retraction (lowering) of the die unit, to automatically move said bridging members clear of the slot whereby to then permit unobstructed passage through said slot of the pusher fingers which engage and advance each sheet metal body to and from the die unit.
US Patent References:
Mechanical device
Berger - October 1967 - 3344647
TOOL WITH WEDGE-OPERATED JAW SEGMENTS
Galan et al. - July 1969 - 3455140
FLANGING DIE
McCoy - August 1969 - 3460500
DIE SET UNIT AND METHOD FOR CAN MANUFACTURE
Patarini et al. - September 1969 - 3468153
SPLIT FLANGING DIE UNIT
McCoy - November 1970 - 3540260
Mechanical device
Berger - October 1967 - 3344647
TOOL WITH WEDGE-OPERATED JAW SEGMENTS
Galan et al. - July 1969 - 3455140
FLANGING DIE
McCoy - August 1969 - 3460500
DIE SET UNIT AND METHOD FOR CAN MANUFACTURE
Patarini et al. - September 1969 - 3468153
SPLIT FLANGING DIE UNIT
McCoy - November 1970 - 3540260
Application Number:
05/430034
Publication Date:
11/05/1974
Filing Date:
01/02/1974
View Patent Images:
Export Citation:
Assignee:
Carando Machine Works (Stockton, CA)
Primary Class:
Other Classes:
72/466.900
International Classes:
B21D39/20; B21D41/02; B21D39/08; B21D41/00; B21D41/02
Field of Search:
72/392,404,405,465,466,422,428,441,451 113/12AA
Primary Examiner:
Lanham C. W.
Assistant Examiner:
Duzan, James R.
Attorney, Agent or Firm:
Webster, Roger B.
Claims:
I claim
1. A die-stabilizing mechanism for a flanging die unit power-movable between a lowered position with a cylindrical sheet metal body pre-positioned in alinement thereabove and a raised position engaging in the adjacent end of said body to form an out-turned flange thereon, the die unit embodying die halves which together define a horizontal slot through the die unit, and there being power-advanced body-engaging pusher fingers which pass through the slot when the die unit is in lowered position but are clear of the slot when the die unit is in raised position; the die-stabilizing mechanism including a stop mounted in connection with the die unit to one side of the slot, a blocking member mounted in connection with the die unit to the other side of the slot, said blocking member being movable between a non-working position clear of the slot when the die unit is in lowered position and a working position spanning the slot below the die halves and engaging the slot whereby to then block said die halves against deflection toward each other when the die unit is in raised position, and means associated with the die unit operative to cause movement of said blocking member from its non-working position to its working position in response to movement of said die unit from its lowered position to its raised position.
2. A die-stabilizing mechanism, as in claim 1, in which said means includes a cam and follower assembly responsive to movement of the die unit from its lowered to raised position, and a motion-transmitting element connected between the cam and follower assembly and the blocking member.
3. A die-stabilizing mechanism, as in claim 2, in which the blocking member is turnably mounted, and said motion-transmitting element is a rod eccentrically pivoted at one end to the blocking member.
4. A die-stabilizing mechanism, as in claim 3, in which the other end of the rod is connected to the cam and follower assembly, the latter urging the rod in one direction when the die unit is moved to its lowered position; there being a spring associated with the rod and urging the rod in the opposite direction when the die unit is moved to its raised position.
5. A die-stabilizing mechanism, as in claim 1, in which the blocking member is one leg of a turnably mounted bellcrank lever; and said means includes a rod pivotally connected at one end to the other leg of the bellcrank lever, and a cam and follower assembly responsive to said movement of the die unit to its raised position and connected to the other end of the rod.
6. A die-stabilizing mechanism, as in claim 5, in which the rod is reciprocably mounted on and extends at said other end laterally beyond the die unit; and said assembly includes a fixed vertical cam, and a cam follower on such other end of the rod.
7. A die-stabilizing mechanism, as in claim 1, in which said means includes a reciprocably mounted rod, a spring arranged with the rod and yieldably urging the same in one direction upon movement of the die unit to its raised position, and a cam and follower assembly associated with the rod and urging the same in the opposite direction upon movement of the die unit to its lowered position.
8. A die-stabilizing mechanism, as in claim 1, in which the blocking member is one leg of a turnably mounted bellcrank lever; and said means includes a reciprocably mounted rod pivotally connected at one end to the other leg of the bellcrank lever, and cam-controlled instrumentalities associated with the rod and urging the same in a direction to turn the bellcrank lever to a position with the blocking member forming leg thereof in working position when the die unit is moved to its raised position.
9. A die-stabilizing mechanism, as in claim 1, including a pair of stops mounted in connection with the die unit to one side of, and longitudinally spaced relative to, the slot; there being a cooperating pair of said movable blocking members mounted in connection with the die unit to the other side of, and correspondingly longitudinally spaced relative to, the slot; and said means being operative to cause simultaneous movement of said blocking members from non-working position to working position.
10. A die-stabilizing mechanism, as in claim 9, in which said means includes a motion-control cam and follower assembly corresponding to each blocking member, and a motion-transmitting connection between each cam and follower assembly and the corresponding blocking member; said assemblies being simultaneously operative upon movement of the die unit to its raised position.
1. A die-stabilizing mechanism for a flanging die unit power-movable between a lowered position with a cylindrical sheet metal body pre-positioned in alinement thereabove and a raised position engaging in the adjacent end of said body to form an out-turned flange thereon, the die unit embodying die halves which together define a horizontal slot through the die unit, and there being power-advanced body-engaging pusher fingers which pass through the slot when the die unit is in lowered position but are clear of the slot when the die unit is in raised position; the die-stabilizing mechanism including a stop mounted in connection with the die unit to one side of the slot, a blocking member mounted in connection with the die unit to the other side of the slot, said blocking member being movable between a non-working position clear of the slot when the die unit is in lowered position and a working position spanning the slot below the die halves and engaging the slot whereby to then block said die halves against deflection toward each other when the die unit is in raised position, and means associated with the die unit operative to cause movement of said blocking member from its non-working position to its working position in response to movement of said die unit from its lowered position to its raised position.
2. A die-stabilizing mechanism, as in claim 1, in which said means includes a cam and follower assembly responsive to movement of the die unit from its lowered to raised position, and a motion-transmitting element connected between the cam and follower assembly and the blocking member.
3. A die-stabilizing mechanism, as in claim 2, in which the blocking member is turnably mounted, and said motion-transmitting element is a rod eccentrically pivoted at one end to the blocking member.
4. A die-stabilizing mechanism, as in claim 3, in which the other end of the rod is connected to the cam and follower assembly, the latter urging the rod in one direction when the die unit is moved to its lowered position; there being a spring associated with the rod and urging the rod in the opposite direction when the die unit is moved to its raised position.
5. A die-stabilizing mechanism, as in claim 1, in which the blocking member is one leg of a turnably mounted bellcrank lever; and said means includes a rod pivotally connected at one end to the other leg of the bellcrank lever, and a cam and follower assembly responsive to said movement of the die unit to its raised position and connected to the other end of the rod.
6. A die-stabilizing mechanism, as in claim 5, in which the rod is reciprocably mounted on and extends at said other end laterally beyond the die unit; and said assembly includes a fixed vertical cam, and a cam follower on such other end of the rod.
7. A die-stabilizing mechanism, as in claim 1, in which said means includes a reciprocably mounted rod, a spring arranged with the rod and yieldably urging the same in one direction upon movement of the die unit to its raised position, and a cam and follower assembly associated with the rod and urging the same in the opposite direction upon movement of the die unit to its lowered position.
8. A die-stabilizing mechanism, as in claim 1, in which the blocking member is one leg of a turnably mounted bellcrank lever; and said means includes a reciprocably mounted rod pivotally connected at one end to the other leg of the bellcrank lever, and cam-controlled instrumentalities associated with the rod and urging the same in a direction to turn the bellcrank lever to a position with the blocking member forming leg thereof in working position when the die unit is moved to its raised position.
9. A die-stabilizing mechanism, as in claim 1, including a pair of stops mounted in connection with the die unit to one side of, and longitudinally spaced relative to, the slot; there being a cooperating pair of said movable blocking members mounted in connection with the die unit to the other side of, and correspondingly longitudinally spaced relative to, the slot; and said means being operative to cause simultaneous movement of said blocking members from non-working position to working position.
10. A die-stabilizing mechanism, as in claim 9, in which said means includes a motion-control cam and follower assembly corresponding to each blocking member, and a motion-transmitting connection between each cam and follower assembly and the corresponding blocking member; said assemblies being simultaneously operative upon movement of the die unit to its raised position.
Description:
BACKGROUND OF THE INVENTION
As disclosed in U.S. Pat. No. 3,540,260, the flanging die unit--adapted to be forcefully engaged in one end of an upstanding, initially open-ended, cylindrical, sheet metal body for a drum or pail--is operative to form a continuous out-turned flange on such end of the body; the die unit--while essentially circular--being split diametrally into half-circle halves having a slot therebetween for the free passage through the die unit of a horizontally power-advanced upstanding pusher finger employed to move the sheet metal body to and from the position in which said body is disposed for the flanging operation. Under the relatively great force of the flanging engagement of the die unit with said one end of the sheet metal body, and half-circle die halves tend to deflect toward each other, frequently causing the production of a faulty flange as well as impairing the subsequent stripping of the die unit from said sheet metal body. The present invention was conceived in a successful effort to solve such problem.
SUMMARY OF THE INVENTION
The present invention provides, as a major object, a die-stabilizing mechanism for a split flanging die unit of the type disclosed in U.S. Pat. No. 3,540,260, and as employed to form a continuous out-turned flange on an end of an initially open-ended, cylindrical, sheet metal body for a drum or pail; the die unit including half-circle die halves having a diametral slot therebetween, and the die-stabilizing mechanism embodying bridging members arranged to span the slot between the half-circle die halves and automatically block the same against deflection toward each other when the die unit is forcefully advanced into flanging relation with such one end of the sheet metal body, and to automatically move clear of such slot when the die unit is retracted from said body whereby to then permit unobstructed passage through said slot of the pusher fingers which engage and advance each sheet metal body to and from the die unit.
The present invention provides, as a further object, a stabilizing mechanism, for the purpose described, which is designed for ease and economy of manufacture.
The present invention provides, as a still further object, a practical, reliable, and durable stabilizing mechanism, for the purpose described, and one which is exceedingly effective for the purpose for which it is designed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the split flanging die unit which embodies the die-stabilizing mechanism of the present invention.
FIG. 2 is a transverse vertical sectional elevation taken substantially on line 2--2 of FIG. 1; the view showing the die unit retracted (lowered).
FIG. 3 is a horizontal section taken substantially on line 3--3 of FIG. 2; the view showing--in full lines--the die-stabilizing mechanism in non-working position when the die unit is retracted (lowered).
FIG. 4 is a transverse sectional elevation taken substantially on line 4--4 of FIG. 3; the view showing--in full lines--the die unit retracted (lowered) and with the die-stabilizing mechanism in non-working position, and--in broken lines--the die unit advanced (raised) and with the die-stabilizing mechanism in working position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more particularly to the drawings and to the characters of reference marked thereon, the die-stabilizing mechanism, as hereinafter described, is especially adapted for use in connection with a split flanging die unit, indicated generally at 1, of the type disclosed in U.S. Pat. No. 3,540,260 wherein such split flanging die unit 1 is circular and fixed in a vertical axis position on a horizontal bed plate 2 supported for up-and-down movement by vertically reciprocable posts 3. The bed plate 2 is disposed in a gap in a longitudinal table 4 on which each upstanding cylindrical sheet metal body 5 is fed to, and moved away from, a flanging position alined above, and for subsequent flanging engagement by, the die unit 1; such position of the body 5 being shown in broken lines in FIG. 2, and in full lines in FIG. 4. The table 4 is carried on a main frame 6 which also serves as the support for the posts 3; the latter being suitably power-raised and lowered by means (not shown) timed to the movement of such cylindrical body 5 to and from the aforesaid flanging position.
The cylindrical sheet metal bodies 5 are individually and successively fed to, and subsequently moved away from, said flanging position by one of a number of upstanding pusher fingers 7 on the upper run of a driven endless chain 8.
In the cycle of operation, the die unit supporting bed plate 2 is retracted to its lowered position (see FIG. 2 and the full line position of FIG. 4) by posts 3 prior to each cylindrical body 5 being finger-advanced to flanging position. Thereafter, by reverse operation of the posts 3, the bed plate 2 (and the die unit thereon) is upwardly advanced to its raised position (see the broken line position of FIG. 4); such raising motion of the die unit 1 driving it forcefully into the lower end of the cylindrical sheet metal body 5 occupying said flanging position; said body 5-- during the flanging operation--being engaged at the top by a suitable stop or die head (not shown).
When the bed plate 2, and the die unit 1 thereon, is in raised position during a flanging operation, the pusher fingers 7 move in a path below said bed plate and die unit. However, to permit of the passage of the pusher fingers 7 through such die unit and bed plate when the same are retracted to lowered position and lie in the path of said fingers, the die unit 1 is diametrally split to form a vertical slot 9 in longitudinal alinement with the path of travel of said pusher fingers 7; the bed plate 2 being correspondingly slotted, as at 10, for the same purpose.
The die unit 1, being diametrally split, comprises two substantially half-circle die halves, each indicated generally at 11 and fixed to the corresponding portion of the bed plate 2.
Upon the split flanging die unit 1 being upwardly advanced to raised position and into flanging engagement with the adjacent end of the cylindrical sheet metal body 5 pre-positioned in flanging position, the relatively great force of such flanging engagement tends to deflect the half-circle die halves 11 toward each other; this frequently causing the production of a faulty flange on, as well as impairing the subsequent stripping of the die unit from, said sheet metal body 5.
The die-stabilizing mechanism of the present invention precludes the occurrence of such deflection of the half-circle die halves 11; said mechanism being constructed and functioning as follows:
The bed plate 2 is fitted on the under face and to one side of the slot 10 with a pair of spaced, transverse, horizontal slot-bridging units, each indicated generally at 12. As such slot-bridging units 12 are substantially alike, a description of one will here suffice for both.
Each slot-bridging unit 12 comprises a heavy-duty bellcrank lever 13 vertically pivoted, as at 14, for horizontal swinging between a non-working position wholly clear of the longitudinal vertical plane of the die slot 9 and bed plate slot 10, and a working position with the adjacent bellcrank lever leg 15 transversely spanning or bridging such slots immediately below the same. In such working position of the bellcrank lever 13, the leg 15--which in effect serves as a blocking dog--not only bridges the slots 9-10, but also firmly abuts against the end of a normally fixed, cooperating stop 16 mounted in connection with the under face of the bed plate 2 to the side of slot 10 opposite said bellcrank lever 13; such stop 16 always occupying a position clear of the slot 10.
The stop 16 is--as shown--in the form of an elongated slide carried in a guide 17; there being a compression spring 18-- under load--between opposed facing abutments 19-20 on such stop and guide, while an adjustment screw 21 extends into engagement with abutment 19 from the rear end of said guide 17. With such arrangement, the stop 16 is normally held fixed against retraction by means of the adjustment screw 21, while abutment 19 is urged against such screw by spring 18.
The bellcrank lever 13 is automatically swung, in the manner now to be described, to the aforesaid non-working and working positions upon the split flanging die unit 1 being retracted to lowered position and advanced to raised position, respectively.
A short linkage 22 is pivotally connected between the free end of leg 23 of bellcrank lever 13 and the inner end of a push-pull rod 24 which extends laterally outward from such linkage; the angular relationship of the bellcrank lever 13, linkage 22, and push-pull rod 24 is such that when such push-pull rod is drawn outwardly, the bellcrank lever 13 is swung to its non-working position, as shown in full lines in FIG. 3, while an inward thrust of such push-pull rod 24 swings the bellcrank lever 13 to its working position with the legs 15 bridging the slots 9-10 and abutting the stop 16 as shown in broken lines in FIG. 3. The linkage pivots are indicated at 25-26.
The push-pull rod 24 extends, intermediate its ends, through a guide 27 fixed in connection with an adjacent portion of the under face of the bed plate 2. Within the confines of the guide 27, the push-pull rod 24 is surrounded by a compression spring 28 disposed between a collar 29 on said rod and the rear end plate 30 of guide 27.
When the split flanging die unit 1 is retracted to its lowered position, the push-pull rod 24 is drawn outwardly, compressing the spring 28, and swinging the bellcrank lever 13 in its non-working position; such outward motion of the push-pull rod being accomplished as follows:
At its outer end, the push-pull rod 24 is fitted with a transverse axis roller 31 which rides the outer edge of a vertically disposed cam 32 secured, in suitable manner, in fixed relation to the frame 6. The outer edge of the cam 32 is generated to a form (see FIG. 4) such that when the split flanging die unit 1 retracts to its lowered position, the roller 31 rides downwardly on the outer edge of the cam 32 (as a follower) and is urged outwardly, imparting a corresponding motion to the push-pull rod 24 resulting, as aforesaid, in compression of the spring 28, and swinging of the bellcrank lever 13 to its non-working position.
Conversely, when the split flanging die unit is advanced to its raised position, the cam 32 permits the camfollowing roller 31 to shift in an inward direction, and such that the push-pull rod 24 thrusts inwardly (under the influence of spring 28) and causes the bellcrank lever 13 to swing to its working position, with the leg 15--serving as a blocking dog--spanning beneath the slots 9-10 and abutting the stop 16.
As will be apparent, the slot-bridging units 12 function at the same time, and so that--upon advancing of the split flanging die unit to its raised position--the dog-forming legs 15 are simultaneously swung into their slot-bridging position in abutment with the stops 16. Thus, when the split flanging die unit 1 is forcefully driven upwardly into the adjacent end of the pre-positioned sheet metal body 5, the relatively great force or load then imposed on the die halves 11 is precluded from deflecting such die halves toward each other and as otherwise may occur due to extremely slight lateral yielding of posts 3.
With the described die-stabilizing mechanism in use, the flange 33 is perfectly formed on the adjacent end of the sheet metal body 5, and--beyond this--the die unit can be subsequently stripped from such body 5 without difficulty.
Upon completion of the formation of the flange 33 on a sheet metal body 5, the split flanging die unit 1 is retracted to its lowered position, and--in the course of such retraction--the cams 32, acting on the cam-following rollers 31, cause the push-pull rods 24 to be drawn outwardly. In turn, the bellcrank levers 13 are swung to their non-working positions wholly clear of the slots 9-10; this to the end that, with the split flanging die unit in such lowered position, said slots 9-10 are wholly unobstructed, and the pusher fingers 7 can freely pass through the slots.
From the foregoing description, it will be readily seen that there has been produced such a stabilizing mechanism, for the purpose described, as substantially fulfills the objects of the invention, as set forth herein.
While this specification sets forth in detail the present and preferred construction of the stabilizing mechanism, for the purpose described, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention as defined by the appended claims.
As disclosed in U.S. Pat. No. 3,540,260, the flanging die unit--adapted to be forcefully engaged in one end of an upstanding, initially open-ended, cylindrical, sheet metal body for a drum or pail--is operative to form a continuous out-turned flange on such end of the body; the die unit--while essentially circular--being split diametrally into half-circle halves having a slot therebetween for the free passage through the die unit of a horizontally power-advanced upstanding pusher finger employed to move the sheet metal body to and from the position in which said body is disposed for the flanging operation. Under the relatively great force of the flanging engagement of the die unit with said one end of the sheet metal body, and half-circle die halves tend to deflect toward each other, frequently causing the production of a faulty flange as well as impairing the subsequent stripping of the die unit from said sheet metal body. The present invention was conceived in a successful effort to solve such problem.
SUMMARY OF THE INVENTION
The present invention provides, as a major object, a die-stabilizing mechanism for a split flanging die unit of the type disclosed in U.S. Pat. No. 3,540,260, and as employed to form a continuous out-turned flange on an end of an initially open-ended, cylindrical, sheet metal body for a drum or pail; the die unit including half-circle die halves having a diametral slot therebetween, and the die-stabilizing mechanism embodying bridging members arranged to span the slot between the half-circle die halves and automatically block the same against deflection toward each other when the die unit is forcefully advanced into flanging relation with such one end of the sheet metal body, and to automatically move clear of such slot when the die unit is retracted from said body whereby to then permit unobstructed passage through said slot of the pusher fingers which engage and advance each sheet metal body to and from the die unit.
The present invention provides, as a further object, a stabilizing mechanism, for the purpose described, which is designed for ease and economy of manufacture.
The present invention provides, as a still further object, a practical, reliable, and durable stabilizing mechanism, for the purpose described, and one which is exceedingly effective for the purpose for which it is designed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the split flanging die unit which embodies the die-stabilizing mechanism of the present invention.
FIG. 2 is a transverse vertical sectional elevation taken substantially on line 2--2 of FIG. 1; the view showing the die unit retracted (lowered).
FIG. 3 is a horizontal section taken substantially on line 3--3 of FIG. 2; the view showing--in full lines--the die-stabilizing mechanism in non-working position when the die unit is retracted (lowered).
FIG. 4 is a transverse sectional elevation taken substantially on line 4--4 of FIG. 3; the view showing--in full lines--the die unit retracted (lowered) and with the die-stabilizing mechanism in non-working position, and--in broken lines--the die unit advanced (raised) and with the die-stabilizing mechanism in working position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now more particularly to the drawings and to the characters of reference marked thereon, the die-stabilizing mechanism, as hereinafter described, is especially adapted for use in connection with a split flanging die unit, indicated generally at 1, of the type disclosed in U.S. Pat. No. 3,540,260 wherein such split flanging die unit 1 is circular and fixed in a vertical axis position on a horizontal bed plate 2 supported for up-and-down movement by vertically reciprocable posts 3. The bed plate 2 is disposed in a gap in a longitudinal table 4 on which each upstanding cylindrical sheet metal body 5 is fed to, and moved away from, a flanging position alined above, and for subsequent flanging engagement by, the die unit 1; such position of the body 5 being shown in broken lines in FIG. 2, and in full lines in FIG. 4. The table 4 is carried on a main frame 6 which also serves as the support for the posts 3; the latter being suitably power-raised and lowered by means (not shown) timed to the movement of such cylindrical body 5 to and from the aforesaid flanging position.
The cylindrical sheet metal bodies 5 are individually and successively fed to, and subsequently moved away from, said flanging position by one of a number of upstanding pusher fingers 7 on the upper run of a driven endless chain 8.
In the cycle of operation, the die unit supporting bed plate 2 is retracted to its lowered position (see FIG. 2 and the full line position of FIG. 4) by posts 3 prior to each cylindrical body 5 being finger-advanced to flanging position. Thereafter, by reverse operation of the posts 3, the bed plate 2 (and the die unit thereon) is upwardly advanced to its raised position (see the broken line position of FIG. 4); such raising motion of the die unit 1 driving it forcefully into the lower end of the cylindrical sheet metal body 5 occupying said flanging position; said body 5-- during the flanging operation--being engaged at the top by a suitable stop or die head (not shown).
When the bed plate 2, and the die unit 1 thereon, is in raised position during a flanging operation, the pusher fingers 7 move in a path below said bed plate and die unit. However, to permit of the passage of the pusher fingers 7 through such die unit and bed plate when the same are retracted to lowered position and lie in the path of said fingers, the die unit 1 is diametrally split to form a vertical slot 9 in longitudinal alinement with the path of travel of said pusher fingers 7; the bed plate 2 being correspondingly slotted, as at 10, for the same purpose.
The die unit 1, being diametrally split, comprises two substantially half-circle die halves, each indicated generally at 11 and fixed to the corresponding portion of the bed plate 2.
Upon the split flanging die unit 1 being upwardly advanced to raised position and into flanging engagement with the adjacent end of the cylindrical sheet metal body 5 pre-positioned in flanging position, the relatively great force of such flanging engagement tends to deflect the half-circle die halves 11 toward each other; this frequently causing the production of a faulty flange on, as well as impairing the subsequent stripping of the die unit from, said sheet metal body 5.
The die-stabilizing mechanism of the present invention precludes the occurrence of such deflection of the half-circle die halves 11; said mechanism being constructed and functioning as follows:
The bed plate 2 is fitted on the under face and to one side of the slot 10 with a pair of spaced, transverse, horizontal slot-bridging units, each indicated generally at 12. As such slot-bridging units 12 are substantially alike, a description of one will here suffice for both.
Each slot-bridging unit 12 comprises a heavy-duty bellcrank lever 13 vertically pivoted, as at 14, for horizontal swinging between a non-working position wholly clear of the longitudinal vertical plane of the die slot 9 and bed plate slot 10, and a working position with the adjacent bellcrank lever leg 15 transversely spanning or bridging such slots immediately below the same. In such working position of the bellcrank lever 13, the leg 15--which in effect serves as a blocking dog--not only bridges the slots 9-10, but also firmly abuts against the end of a normally fixed, cooperating stop 16 mounted in connection with the under face of the bed plate 2 to the side of slot 10 opposite said bellcrank lever 13; such stop 16 always occupying a position clear of the slot 10.
The stop 16 is--as shown--in the form of an elongated slide carried in a guide 17; there being a compression spring 18-- under load--between opposed facing abutments 19-20 on such stop and guide, while an adjustment screw 21 extends into engagement with abutment 19 from the rear end of said guide 17. With such arrangement, the stop 16 is normally held fixed against retraction by means of the adjustment screw 21, while abutment 19 is urged against such screw by spring 18.
The bellcrank lever 13 is automatically swung, in the manner now to be described, to the aforesaid non-working and working positions upon the split flanging die unit 1 being retracted to lowered position and advanced to raised position, respectively.
A short linkage 22 is pivotally connected between the free end of leg 23 of bellcrank lever 13 and the inner end of a push-pull rod 24 which extends laterally outward from such linkage; the angular relationship of the bellcrank lever 13, linkage 22, and push-pull rod 24 is such that when such push-pull rod is drawn outwardly, the bellcrank lever 13 is swung to its non-working position, as shown in full lines in FIG. 3, while an inward thrust of such push-pull rod 24 swings the bellcrank lever 13 to its working position with the legs 15 bridging the slots 9-10 and abutting the stop 16 as shown in broken lines in FIG. 3. The linkage pivots are indicated at 25-26.
The push-pull rod 24 extends, intermediate its ends, through a guide 27 fixed in connection with an adjacent portion of the under face of the bed plate 2. Within the confines of the guide 27, the push-pull rod 24 is surrounded by a compression spring 28 disposed between a collar 29 on said rod and the rear end plate 30 of guide 27.
When the split flanging die unit 1 is retracted to its lowered position, the push-pull rod 24 is drawn outwardly, compressing the spring 28, and swinging the bellcrank lever 13 in its non-working position; such outward motion of the push-pull rod being accomplished as follows:
At its outer end, the push-pull rod 24 is fitted with a transverse axis roller 31 which rides the outer edge of a vertically disposed cam 32 secured, in suitable manner, in fixed relation to the frame 6. The outer edge of the cam 32 is generated to a form (see FIG. 4) such that when the split flanging die unit 1 retracts to its lowered position, the roller 31 rides downwardly on the outer edge of the cam 32 (as a follower) and is urged outwardly, imparting a corresponding motion to the push-pull rod 24 resulting, as aforesaid, in compression of the spring 28, and swinging of the bellcrank lever 13 to its non-working position.
Conversely, when the split flanging die unit is advanced to its raised position, the cam 32 permits the camfollowing roller 31 to shift in an inward direction, and such that the push-pull rod 24 thrusts inwardly (under the influence of spring 28) and causes the bellcrank lever 13 to swing to its working position, with the leg 15--serving as a blocking dog--spanning beneath the slots 9-10 and abutting the stop 16.
As will be apparent, the slot-bridging units 12 function at the same time, and so that--upon advancing of the split flanging die unit to its raised position--the dog-forming legs 15 are simultaneously swung into their slot-bridging position in abutment with the stops 16. Thus, when the split flanging die unit 1 is forcefully driven upwardly into the adjacent end of the pre-positioned sheet metal body 5, the relatively great force or load then imposed on the die halves 11 is precluded from deflecting such die halves toward each other and as otherwise may occur due to extremely slight lateral yielding of posts 3.
With the described die-stabilizing mechanism in use, the flange 33 is perfectly formed on the adjacent end of the sheet metal body 5, and--beyond this--the die unit can be subsequently stripped from such body 5 without difficulty.
Upon completion of the formation of the flange 33 on a sheet metal body 5, the split flanging die unit 1 is retracted to its lowered position, and--in the course of such retraction--the cams 32, acting on the cam-following rollers 31, cause the push-pull rods 24 to be drawn outwardly. In turn, the bellcrank levers 13 are swung to their non-working positions wholly clear of the slots 9-10; this to the end that, with the split flanging die unit in such lowered position, said slots 9-10 are wholly unobstructed, and the pusher fingers 7 can freely pass through the slots.
From the foregoing description, it will be readily seen that there has been produced such a stabilizing mechanism, for the purpose described, as substantially fulfills the objects of the invention, as set forth herein.
While this specification sets forth in detail the present and preferred construction of the stabilizing mechanism, for the purpose described, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention as defined by the appended claims.