Title:
DEVICE FOR MAINTAINING UNINTERRUPTED FEEDING OF BLANKS FROM THE BOTTOM OF A STACK
United States Patent 3790163


Abstract:
In a device for feeding envelope blanks from the bottom of a stack, the bottom blank is removed from the stack by engaging the front edge of the bottom blank with a blank engaging assembly which engages the front edge and guides it into engagement with a feed cylinder which thereafter transports the bottom blank to other transfer cylinders in the device. Uninterrupted timely engagement of each successive bottom blank in the stack by the engaging assembly is provided by adjustment of a supporting plate while the device is in operation. The plate is arranged to support the stack of blanks and is pivotally connected to the frame of the device. Eccentric adjustment members contacting the underside of the support plate rotate to raise and lower a portion of the plate relative to the disc elements of the blank engaging assembly and prevent movement of the stack of blanks in the forward direction or in the other extreme rearward movement or push back of the bottom sheet by the disc elements.



Inventors:
HELM H
Application Number:
05/237356
Publication Date:
02/05/1974
Filing Date:
03/23/1972
Assignee:
SMITHE F MACHINE CO INC,US
Primary Class:
Other Classes:
271/101, 271/171
International Classes:
B65H1/06; B65H3/28; (IPC1-7): B65H1/06; B65H3/08
Field of Search:
271/61R,61BF,29,32,41,165,171,101
View Patent Images:
US Patent References:
3655181PRINTING PRESS FEEDER1972-04-11Paulson
3385593Apparatus for feeding individual sheets of paper or the like from the bottom of a stack1968-05-28Snellman
3380353Apparatus for producing lined envelopes1968-04-30Mittermayer
3265383Film sheet feeder1966-08-09Shute
1634074Feeder for sheet material1927-06-28Labombarde



Primary Examiner:
Blunk, Evon C.
Assistant Examiner:
Miller, James W.
Attorney, Agent or Firm:
Price Jr., Esq. Stanley J.
Claims:
1. A device for feeding blanks continually from the bottom of a stack comprising,

2. The device set forth in claim 1 wherein the adjustable blank support means includes,

3. The device set forth in claim 2 wherein the adjustment means for the blank support means includes,

4. The device set forth in claim 1 wherein the adjustment means for the blank support means includes,

5. The device set forth in claim 2 wherein said other blank support means includes,

Description:
BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a device for feeding blanks from the bottom of a stack and more particularly to apparatus for adjusting a stack support member to provide uninterrupted contact between the bottom blank in the stack and a blank engaging assembly for removal of the bottom blank from the stack.

2. Description of the Prior Art

U. S. Pat. No. 3,599,970 entitled, "Apparatus For Feeding Blanks From The Bottom Of A Stack" discloses apparatus for feeding envelope blanks from the bottom of a stack by engaging the front edge of the bottom blank with a suction member protruding from a cylindrical sheet drum constructed to engage the front edge of the blank removed by the suction member downwardly from the stack. Often the blanks are deformed along the edges and are stacked either concave upwardly or concave downwardly in the feeding device, depending upon how a given group of blanks is placed in the feeding device by the operator. The concavity of the blanks, and the orientation of that concavity in the feeding device, is not discernible generally by visual inspection, and can cause erratic operation of the feeding device because the support plate and the discs are adjusted for either straight blanks or blanks having the type and degree of concavity exhibited by the lowermost blanks in the stack. A change in concavity of a given blank may require a change in the setting of the plate relative to the discs.

With some prior art feeder devices, it is necessary to stop the machine and reassemble the stack or make time-consuming manual adjustments of the support members and feeder assembly to correct for changes in blank concavity. U. S. Pat. No. 3,380,353 illustrates a feeding device having a stack support member and a blank engaging member mounted on supporting shafts that might be adjustable when the machine is not in operation. U. S. Pat. No. 1,312,539 describes a plurality of sheet support members under the rearward portion of the stack with the central support member arranged to depress the center portion of the stack toward a blank engaging member. Prior to engagement of the bottom sheet the central support member is pulled rapidly away from the bottom sheet to cause the sheet to move away from the stack. The arrangement of the central support member prevents periodic or continuous adjustment of the sheet support members required by changing blank concavity during operation of the device.

U. S. Pat. No. 1,939,193 describes a device for feeding sheets from a stack in which the edges of the sheets adhere together by separating the rear edge of the sheet from the stack simultaneously with separation of the front edge by synchronized operation of a pair of sheet engaging members. That patent also describes several arrangements for the stack with the front edge tilted downwardly or upward y, or with the stack horizontal. The stack is always fixed in position during the sheet feeding operation.

U.S. Pat. No. 2,425,936, describes the stack supported on a cylindrical drum and thereby maintained in a downwardly concave configuration of the stack itself during operation. The front edge of the stack is supported by a plurality of laths and replaceable tongues which are mounted in fixed position during operation. The stack is vibrated to separate the bottom sheet from the rest of the stack.

U.S. Pat. No. 999,936 describes a newspaper feeding device having a downwardly inclined support tray fixed in position during operation under the rearward portion of the paper sheets. The forward portion of the sheets is maintained substantially horizontal before and during engagement of the forward edge of the sheet by an engaging member.

There is a need for a sheet feeding device that is adjustable during operation to compensate for variations in the condition of the sheet blanks and especially for such a device having a readily operable and simply constructed adjustable blank stack support assembly.

SUMMARY OF THE INVENTION

This invention relates to a device for continuously feeding successive single blanks from the bottom of a stack and includes a blank engaging assembly for engaging and removing the bottom blanks for transfer to a blank feeder assembly. The device also has front stack support members supporting the forward edge of the stack. An adjustable stack support plate is pivotally mounted on the device to support the rear edge of the stack and to adjust the position of the stack relative to the blank engaging assembly. A rotatably mounted support plate adjusting assembly contacts a surface of the plate for adjustment of the position of the plate relative to the plane of contact between the sheet engaging assembly and the front edge of the bottom sheet in the stack. The adjusting assembly can be actuated intermittently or continuously during operation of the device to correct for concavity and other deformities in individual blanks or a series of blanks.

This invention provides a high speed blank feeding apparatus employing a rotating feed member having a blank engaging assembly and a continuously adjustable stack supporting assembly for intermittent or continuous adjustment, during operation, of the stack, and the front edge thereof relative to the blank engaging assembly.

This invention enables the rapid feeding of blanks avoiding and/or correcting malfunction of the device caused by concavity or other deformity in the blanks.

These and other objects and advantages of this invention will be more completely disclosed and described in the following specification, the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view, partially in cross section, of the feeder device of this invention.

FIG. 2 is a side elevation taken in cross section along the Line II--II of FIG. 1, and includes a' stack of blanks illustrated in phantom lines.

FIG. 3 is a view taken in cross section along the Line III--III of FIG. 1, illustrating the detailed construction of the adjustable stack support plate.

FIG. 4 is a fragmentary view taken in cross section along the Line IV--IV of FIG. 1, illustrating in detail the construction of the support plate adjustment members.

FIG. 5 is similar to FIG. 2 and shows the device in cross section taken along the Line II--II of FIG. 1 and showing the adjustable stack support table and adjustment member in several alternative stages of adjustment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2, a sheet or blank feeding device, indicated generally by reference numeral 10, is arranged to remove a bottom blank 12 from a stack of blanks 14. The blanks in stack 14 can be envelope blanks or other types of sheets and the like.

A stack support plate 30 is arranged to support a major portion of the rearward portion of the stack 14 and has a pair of upwardly extending register rods 32 and 34 arranged to support and provide a register reference for the blanks in stack 14 during stacking of the blanks and feeding of the blanks to the printing or other working portions of the apparatus. A register rod weight ring 33 can be fitted loosely around each of the register rods 32 and 34 to rest upon the top of the stack 14 near each register rod and apply additional downward force to the rear portions of the stack 14. A pair of rotating support discs 36 and 38, suitably secured to vertical shafts 40 and 42, are arranged to support the front portion of the stack, as illustrated particularly in FIG. 2. Disc 36 rotates in counterclockwise direction and disc 38 rotates in clockwise direction in synchronous motion with each other and with other components of the feeding device 10. As shown in FIG. 1, each disc 36 and 38 has a cutout portion or segment 44 which, as described below, permits the blank feed portion of the feeder device 10 to engage the front edge of the bottom blank 12 for removal from the stack.

A knife-shaped support 46 supports the front edge 24 of the stack when the bottom blank 12 is withdrawn from the stack by a sucker shaft, as explained below. Air nozzles 48, associated with support knife 46, act in cooperation with support knife 46 to separate the front edges of the blanks in stack 14 for removal of single blanks from the stack when support knife 46 is in the position illustrated in FIG. 1. While bottom blank 12 is being removed from stack 14, support knife 46 is moved out of supporting relation to stack 14 and the air supply to nozzles 48 is turned off. Support knife 46 can be connected to and actuated by any suitable apparatus such as that illustrated in FIG. 2 consisting of a bell crank 50 connected to support knife 46 and pivoted about pivot shaft 52. A cam roller 54, following a rotating cam surface (not shown in the drawing) reciprocates support knife 46 inwardly beneath the stack 14 and outwardly away therefrom in synchronization with other components of feeder device 10. Air supply to nozzles 48 is controlled to supply air only when support knife 46 is beneath stack 14.

One construction and arrangement of a blank engaging assembly and blank feeding assembly suitable for use with the adjustable stack support assembly of this invention is described as follows. A feed cylinder 58 is positioned beneath the front edge 24 of the stack 14 and has a sucker shaft 60 rotatably mounted therein. Cylinder 58 has an elongated longitudinal opening 62 in its periphery with an edge portion 64 that is hereinafter referred to as the pull out segment 64 of the feed cylinder 58. A plurality of suction ports 66 are positioned longitudinally in the periphery of feed cylinder 58 adjacent to pull out segment 64. Suction is applied through ports 66 in synchronization with other members of feeding device 10 by means of a timed valve not shown in the drawings.

Sucker shaft 60 rotatably mounted in feed cylinder 58 is drivingly connected to feed cylinder 58 through a gear 72 forming a portion of a gear train (not shown) which controls the relative location between feed cylinder 58 and sucker shaft 60. Suitable selection of elements of the gear train connecting sucker shaft 60 and feed cylinder 58 can provide a velocity ratio between sucker shaft 60 and feed cylinder 58 which may vary, for example, as a ratio of 3 to 1, 2 to 1, or 4 to 1. The gear train is constructed to assure that sucker shaft 60 is always in position to engage front edge 24 of the bottom of stack 14 when feed cylinder 58 is in the position illustrated in FIGS. 1 and 2.

Sucker shaft 60 has a plurality of protruding radial extensions 80, 82 and 84. Each radial extension has a plurality of suction ports 88 and is suitably connected to a vacuum device and synchronized to cooperate with other members of feeding device 10 to apply suction to the front edge of bottom blank 12 when the apparatus is in the position illustrated in FIGS. 1 and 2. Radial extensions 80, 82 and 84 can be formed from rubber or other flexible, deformable or resilient material adapted to enhance the engagement between each radial extension and the bottom of front edge 24 of bottom blank 12.

Radial extensions 80, 82 and 84 extend outwardly beyond the periphery of feed cylinder 58 to enable engagement of each radial extension with front edge 24 of bottom blank 12. It is essential that adequate clearance be provided between the other elements of feeding device 10 and radial extensions 80, 82 and 84 to prevent damage to the radial extensions and to the other structural elements of the feeding mechanism 10. After removal from the stack 14, the bottom blank is transferred to other blank transfer and process devices associated with the feeding device 10.

There has been described above one preferred emboidment of the bottom blank engaging means; namely, sucker shaft 60 having protruding radial extensions 80, 82 and 84 mounted on feed cylinder 58. It should be understood that the adjustable stack support plate of this invention can be used with sheet feeding devices having a wide variety of structures for the bottom blank engaging means such as mechanical extensions arranged to bend the front edge of the bottom sheet mechanically or engaging pins arranged to impale the front edge of the bottom sheet and remove it from the stack. The adjustable stack support plate can work with any such device to provide the proper spatial relationship between the front edge of the bottom blank and the blank engaging assembly.

The stack support plate 30, as shown in FIG. 2, has an upper surface 112 under the rearward portion 22 of stack 14. A rigid support frame member 102 is mounted on the frame of feeder device 10 by any suitable means (not shown in the drawing). As illustrated in FIGS. 1 and 3 the frame member 102 has a plurality of lugs 104 extending upwardly therefrom, each lug 104 having a bore 127 extending therethrough. Support plate 30 has a bottom surface 114 from which there extend downwardly a plurality of support plate lugs 126, with each lug having a bore 128 extending therethrough. As shown in FIG. 3, support plate lugs 126 with bores 128 are constructed and arranged for alignment with frame member lugs 104 with bores 127 therethrough to permit the insertion through those bores of pins 108, thereby providing a pivotal connection between the rearward portion of support plate 30 and frame member 102.

A slot 150 extends inwardly from the rear edge of support plate 30 toward the front edge of support plate 30 between register rods 32 and 34. A stack support bar, indicated generally by reference numeral 116, is adjustably mounted on frame member 102 and extends upwardly through slot 150 above the upper surface 112 of support plate 30. As shown in FIG. 2, stack support bar 116 includes a body member 120 having a knurled cross member 122 extending laterally from its upper end and resting on or above upper surface 112 of support plate 30. The stack support bar 116 has a laterally extending cylindrical end portion 119 that is positioned in a transverse bore 121 of base member 118. A longitudinal bore 123 having an internally threaded end portion communicates with the transverse bore 121. An adjusting screw 125 is threadedly secured in the longitudinal bore 123 and has one end portion abutting the cylindrical end portion 119 of support bar 116 and an adjusting handle 127 connected to the other end. The adjusting screw 125 frictionally engages the support bar end portion 116 to maintain the support bar knurled cross member 122 at a preselected fixed height. To adjust the height of the knurled cross member 122 the adjusting screw 125 is rotated by handle 127 to release the cylindrical end portion 119. After the support bar knurled end portion 122 is manually adjusted to a desired height, the end portion of the adjusting screw 125 is again moved into frictional engagement with the support bar end portion 119 by means of handle 127.

The frame member 102 has a vertical bore 129 in which a screw 131 is positioned. A lateral clamp 133 has a threaded bore n which the screw 131 is engaged. A portion of the clamp 133 is in overlying relation with a ledge portion 135 of the base member 118 and frictionally engages the base member 118 to the frame 102. A handle 137 is connected to the screw 131 to control the frictional engagement of the clamp 133 to the base member 118. To adjust the support bar 120 longitudinally relative to the frame member 102 the clamp 133 is removed and the base member 118 is moved longitudinally on the frame 102. With this arrangement both the relative position of the support bar 120 in the plate slot 150 and the vertical height of the knurled cross member 122 may be manually adjusted. In operation, support bar 116 supports the rear edge of stack 14 on its knurled surface and prevents slippage from the stack bottom of sheets other than the blank being removed by the engaging assembly.

FIG. 4 illustrates in detail the construction of the control and adjustment members of the apparatus of this invention. An adjusting shaft 136 is rotatably mounted at its ends within feeder device 10 beneath the lower surface 114 of support plate 30. Adjustment shaft 136 is free to rotate at one end in bracket 134 and, at the other end, is rotatably secured by suitable means such as bracket 132 having associated therewith a locking member 142, illustrated in FIGS. 1 and 4. An adjusting handle 130 is connected to adjusting shaft 136 near locking member 142, for convenience. A plurality of adjusting discs 140 are eccentrically mounted on adjusting shaft 136 and are constructed and arranged to contact the bottom surface 114 of support plate 30. As shown in FIG. 2, rotation of adjusting shaft 136 changes the point of contact between the undersurface 114 of support plate 30 and the point of contact along the periphery of each adjusting disc 140, thereby raising or lowering support plate 30 about its pivotal connection at 108 to frame member 102.

Pertinent aspects of the operation of the feeder device 10 can be described in detail as follows. With the various members of feeder device 10 operating in synchronization, sucker shaft 60 is positioned with radial extensions 80, 82 and 84 extending upwardly beyond the periphery of feed cylinder 58 between the notches 44 of support discs 36 and 38. The front edge 24 of bottom blank 12 in stack 14 is thus exposed and supported by support knife 46 extending beneath the bottom of stack 14. An air blast supplied through nozzles 48 separates the bottom blank 12 from remaining blanks in stack 14 while the radial extensions 80, 82 and 84 engage by suction applied through sucker shaft 60 the front edge 24 of bottom blank 12.

As feed cylinder 58 rotates counterclockwise, support knife 46 moves away from the bottom of stack 14, and sucker shaft 60 with radial extensions 80, 82 and 84 rotates in a clockwise direction to bend the front edge 24 of bottom blank 12 downwardly into the circumferential opening 62 in feed cylinder 58. Then knife support 46 and support discs 36 and 38 are repositioned to support stack 14. Further rotation of feed cylinder 58 moves pull out segment 64 into contact with the upper surface of blank 12 and moves the blank downwardly away from stack 14. When continuous operation of feeder device 10 is accompanied by difficulties and malfunction of the apparatus arising from the forward sliding or rearward push back of blank 12, the device will continue to operate while the radial bottom blank engaging assembly fails to engage the front edge 24 of bottom blank 12.

When malfunction of feeder device 10 is observed, adjustment of the plate height with relation to the discs will eliminate push back of blank 12 if the plate was too low or forward movement of the entire stack 14 if the plate was too high. Adjustment of support plate 30 and stack 14 can be continued until proper operation of feeding device 10 is restored and maintained, at which time locking member 142 is closed to secure the support plate in its adjusted operating position until further adjustment might be necessary.

Operation of the continuously controllable and adjustable support plate for use with a feeding device has been described herein for the relation to a specific type of sheet feeding device. Alternatively, the controllable and adjustable support apparatus described herein can be included in many of the existing sheet feeding devices not specifically described herein. For brevity and clarity, certain of the components have been illustrated diagrammatically. The control devices for rotating and actuating the components in timed relation to each other and the devices for applying suction through the various suction ports in proper sequence have been omitted. The function of those devices is apparent from the previous description and various conventional control devices may be used.

According to the provisions of the patent statutes, I have explained the principle, preferred construction and mode of operation of my invention and have illustrated and described what I now consider to represent its best embodiments. However, it should be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.