US3034784A - Feeding equipment - Google Patents

Description

3 Sheets-Sheet 1 Filed June 10, 1960 INVENTOR. LOPEZ May 15, 1962 J. LOPEZ 3,034,784

v FEEDING EQUIPMENT Filed June 10, 1960 3 Sheets-Sheet 2 I N VEN TOR. J'0l1'N L 0P5 Z 197' 7' OEIVEYS May 15, 1962 Filed June 10, 1960 J. LOPEZ FEEDING EQUIPMENT 3 Sheets-Sheet 3 FIG. .90

INVENTOR. my 4 ope-z 3,034,784 FEEDING EQUIPMENT .lohn Lopez, Westfield, Ni, assignor to Universal Corrugated Box Machinery Corporation, Linden, N.J., a corporation of New Jersey Filed June ll), 1969, Ser. No. 35,301 14 Claims. (Cl. 27129) This invention relates to the art of sheet feeding equipment, more particularly of the type individually to feed folded box blanks at a predetermined rate.

As conducive to an understanding of the invention, it is noted that where rectangular sheets of semi-rigid material such as corrugated paper, laminated paper fiber or the like used, for example, in the manufacture of box blanks, are successively fed to additional processing equip ment such as printing rollers, if the box blank should skew as it is advanced, the printing will be imperfect so that the box blank would have to be discarded, and as the feeding and printing must occur at a relatively high rate of speed, many box blanks will be imperfectly printed before the equipment can be stopped for realignment, with attendant waste and increased cost of production.

In order for the subsequent processing equipment to operate at a high rate of speed, which is essential for mass production, it is vital that the box blanks be fed automatically and rapidly in sequence thereto, at a controllable rate, so that, for example, one box blank will be fed with each cycle of rotation of a printing roller and with substantially no skewing or hesitation in its advance, which would cause improper processing of the box blanks.

Where reciprocating means such as a pusher is used successively to feed the open box blanks, the rate of feed is necessarily slower than it would be with a rotary feed and such reciprocating equipment is more likely to break down. In addition, where the box blanks are of the die cut type having irregular edges, the use of a pusher type feeder is substantially precluded, as it would not necessarily engage a straight edge to advance the box blanks without skewing thereof.

Furthermore, where rectangular sheets of semi-rigid material, such as corrugated paper or the like used in the manufacture of folding boxes, are to be fed automatically one by one from the bottom of a stack, between suitable drive means which discharge individual shee for subsequent processing, where, due to unequal contraction or expansion, the sheets tend to warp, the end edge of the successive bottom most sheet in the stack may not be aligned with the drive means, with the result that the continuous discharge of the sheets may be interrupted requiring manual realignment of such end edge, thereby interrupting the subsequent processing and preventing high speed operation.

Where the stack of box blanks rests on a friction belttype conveyor and a stop is positioned over the conveyor in the path of movement of the box blanks immediately above the bottommost blank so that with advance of the conveyor one blank at a time will be fed, as the frictional engagement of the conveyor with the bottommost box blank may not be equal over the entire area thereof, skewing of the bottommost blank may occur as it is advanced with the disadvantages above noted.

It is accordingly among the objects of the invention to provide a box blank feeding equipment especially suitable for corrugated type box blanks, which is relatively simple in construction and has but few parts which are not likely to become deranged even with long use, and which will operate at a high rate of speed dependably to discharge successive blanks at a controllable rate from the bottom of a stack without likelihood of stoppage of 3,034,784 Patented May 15., 1962 the discharge operation even if the sheets are warped and do not initially have their end edge aligned with the discharge drive means, and with substantially no skewing or hesitation in their advance, and which may be used With box blanks of any type including die cut blanks having irregular edges.

According to the invention, the box blanks are successively fed from the bottom of a stack by means of a suction type conveyor belt in association with a guide arm or gauge which permits only one blank at a time to pass thereunder at a controlled rate.

This application is a continuation-in-part of copending application Serial No. 849,043, filed October 27, 1959, now U.S. Patent No. 2,995,361.

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

FIG. 1 is a top plan view of the feeding equipment,

FIG. 2 is a sectional view thereof taken along line 2-2 of FIG. 1, illustratively showing printing rollers associated with the equipment,

FIG. 3 is a fragmentary end view taken along line 33 of FIG. 2,

FIG. 4 is a view similar to FIG. 2 partly in cross section,

FIG. 5 is a sectional view taken along line 55 of FIG. 4,

FIG. 6 is a fragmentary detail view of an outer back stop taken along lines 6--6 of FIG. 4,

FIG. 7 is an exploded perspective view of one of the outer back stops,

FIG. 8 is a top plan view of an intermediate back stop,

FIG. 9 is a side elevational view of a gauge and. stop assembly,

FIG. 9a is a detail sectional view taken along line 9a-9a of FIG. 9,

FIG. 10 is a sectional view taken along line 101G of FIG. 9, and

FIG. 11 is a detail view of another embodiment of the invention.

Referring now to the drawings, the feeding unit comprises a frame 31 which has a pair of spaced rollers 32 and 33, each mounted on a horizontal axis, said rollers carrying a perforated endless belt 34, a portion of the upper run 35 of which adjacent roller 33 is supported by a plurality of spaced idler rollers 36 and the major portion of which is supported by a plate 30. The rollers 32, 33 are encompassed by a suction chamber 37 connected through duct 38 to a suction unit 39 whereby, upon creation of suction in the chamber 37, a corresponding suction will be created through the perforations in the belt 34 except the portion of which is riding over plate 30.

As shown in FIG. 5, a pair of racks 41 straddle the belt 34 and are secured to the frame 31, said racks being straddled by the vertical legs 42 of elongated L-shaped brackets 4-3, the horizontal legs 44 of which are secured to the frame 31.

Each of the vertical legs 42 of brackets 43 has an elongated horizontal slot 45, through each of which extends the associated reduced diameter end 46 of a shaft 47 that extends transversely across the belt 347 As shown in FIG. 5, a pinion 46 is secured to each of the reduced diameter ends of the shaft inward of the vertical legs 42 of brackets 43 and adjacent thereto, said pinions engaging the associated rack 41. One end of the shaft has a nut 47' thereon, and the other end mounts a handy/heel 48. The shaft 47 extends through bearings 51 in each end of an elongated support 52 that is rectangular in cross section and has its lower ends resting on the frame inwardly of the racks 41 as shown in FIG. 5, said support also extending transversely across the belt 34.

Thus, upon rotation of the handwheel 48, the support 52 will be moved longitudinally of the belt 34, being restrained from rotation by reason of the fact that its ends rest on the frame.

The support serves as a mount for a plurality of box blank back stops 53, each of which, as illustratively shown in FIG. 7, comprises a casting having an inclined front wall '54 with parallel vertical flanges 55 at the side edges extending outwardly from the front wall. Extending rearwardly from the upper and lower ends of the front wall 54 and formed integral therewith are spaced parallel horizontal flanges 56 and 57 adapted to straddle the support 52 and which extend beyond the latter as shown in FIG. 4. A plate 58 is secured as by screws 59 to the free ends of said flanges 56, 57, and by means of a set screw 61 extending through a tapped opening in the plate and reacting against the rear wall of the support 52, the guides 53 may be set to any desired position along the length thereof.

Extending transversely between the parallel vertical flanges 55 are spaced parallel shafts 62, each of which illustratively mounts a pair of rollers 63, the rollers on successive shafts being staggered as shown in FIG. 6, the outer peripheries of said roller extending beyond the outer edges of flames 55 to serve as a moving support for the rear edges 64 of the box blanks, as will be hereinafter described.

In the illustrative embodiment shown, the two outer guides have fins 65 secured to the outer flanges 55 thereof, said fins properly positioning the box blanks on the conveyor belt 34.

In the case of a long box blank, the intermediate guide 53 may have a central fin 65 as shown in FIG. 8, which fits into the slot 65" between adjacent flaps of the box blank. As a result of such fin, the long box blank is effectively guided at three points, which will prevent skewing thereof as the box blank is deposited on conveyor belt 34.

Extending transversely across the belt 34 and positioned above the latter adjacent the roller 33, and longitudinally spaced from the guides 53, is a pair of vertically aligned bars 66 and 67 which extend transversely across the conveyor belt 34. The ends of the bars are secured as by bolts 68 to upstanding standards 69 mounted on each side of frame 31, said bars 67, 68 serving as a support for front gauge and stop assemblies 71 which are slidably mounted on said bars.

As shown in FIGS. 9 and 10, the front gauge and stop assembly 71 comprises a block 74 having a bore 75 extending transversely thereth-rough, in which a bushing 76 is positioned to accommodate the upper shaft 66 for slidable mount of the block 74 thereon. The lower end of the block has a slot 77 therein curved at its upper end, as at 78, to rest on the lower shaft 67. Depending from the block and secured to its rear surface as by screws 79 is a plate 81 having a pair of spaced parallel fingers 82 secured to its lower end as by screws 83 and extending downwardly at an angle from said plate 81 below the lower edge thereof which is spaced from the conveyor belt 34.

Pivotally mounted between the fingers 82 as by a pin 84 is an elongated substantially rectangular lever 85, which extends beneath the block 74 at right angles to the bars 66 and 67. The lever 85 at its free end has a depending lip 86 extending transversely thereacross, which defines a stop member.

Extending upwardly from the pivoted end of the lever 85 is a finger 87 to which is connected one end of a coil spring 88, the other end of which is secured as by screw 89 to the plate 81. Thus, the lever 85 will normally be urged in a clockwise direction from the position shown in FIG. 9 to urge the lip 86 toward the conveyor belt 34.

Extending transversely through the lever between its ends is a slot 91 which is vertically elongated, as shown in FIG. 9. The lever also has a central aperture or bore 4 92 therethrough, which also extends through the slot 91.

Means are provided to pivot said lever in a counterclockwise direction about its pivot pin 84 against the tension of coil spring 88. To this end, an actuator 93 is provided, preferably an air cylinder secured as by screws 94 to the plate 81. The actuator 93, which is in vertical position, has a slidable piston connected to a plunger 95 that is vertically aligned with the central bore 92 in the lever 85. The end of the plunger, which preferably is threaded, mounts the corresponding threaded end of a fitting 96 which extends into said central bore 92, the lower end of said fitting having secured thereto a pin 97 which extends through the elongated transverse slot 91 of the lever 85.

With the construction above described, when the air cylinder 93 is actuated to lift its plunger 95, the pin 97 reacting against the upper end of the transverse slot 91 will pivot the lever 85 in a counterclockwise direction against the tension of coil spring 88 to move the lip 86 away from the conveyor belt 34.

As the plunger 95 of the actuator 93 is moved downwardly, the spring 88 will pivot the lever 85 in a clockwise direction to move the lip 86 toward the conveyor belt 34. However, since the pin 97 extending through the transverse slot 91 is spaced from the lower end thereof, it is apparent that the lever 85 will be free to pivot upwardly independently of plunger 95, in the manner hereinafter to be described, against the tension of coil spring 88.

Supported by the block 74, as shown in FIG. 9, is a belt assembly 100, which desirably comprises a pair of side plates 101 and 102, each substantially in the form of a right angle triangle having its base at its upper end.

Positioned between the plates 101 and 102 at the lower end thereof is a block 103 which is secured in place as by bolts 104. The block 103, which extends transversely between the plates, conforms to the configuration of the lower end of the plates, as is clearly shown in FIG. 9. Positioned between the plates, and extending transversely thereacross at the inclined edges 105 thereof, is a backing plate 106 which is secured to the side Plates as by crews 107.

Means are provided to adjust the vertical position of the belt assembly 100. To this end, the vertical edges 108 of the plates have elongated slots 109 on their inner surface, which serve as guides for the lateral edges of a strip 111 which is positioned against a second strip 112, said two strips being secured to the block 74 as by screws 113. A substantially rectangular plate 115 is positioned between the upper ends of the side plates 101, 102 extending transversely thereacross, and is secured in place as by screws 116. The plate 115 extends over the block 74 and has a hub 117 on its upper surface.

Extending through the hub 117 into a threaded opening 118 in the upper end of block 74 is a screw 119 which has a knob 121 secured to its upper end. The lower end of the knob rests against the top surface of hub 117, and a collar 122 positioned beneath the plate 115 is pinned to said screw. Thus, upon rotation of the knob 121 and the screw 119, the belt assembly may be raised or lowered as desired. Hence, the belt assembly 100 may be adjusted to space the lower end 123 thereof, which defines a gauge, a desired distance from conveyor belt 34 to permit but a single box blank to pass thereunder in the manner hereinafter to be described.

Positioned between the side plates 101 and 102, as shown in FIG. 10, and rotatably mounted on suitable shafts 125 and 126, are pulleys 127 and 128 which are encompassed by an endless belt 129, desirably having a ridged outer surface. The outer run 131 of the belt rides over the backing plate 106, and the inner run 132 of said belt rides around a pulley 133 rotatably mounted between the side plates, and also around an additional drive pulley 134. The shaft 135 mounting the Pulley 133 has reduced diameter ends which extend through elongated slots 136 in each of the side plates, and is adapted to be moved by means of screws 137 extending through bores 138 in said side plates to adjust the tension on the belt 129. The bushing 141 mounting the pulley 134- has a bore extending therethrough, illustratively hexagonal, adapted to receive a correspondingly conformed shaft 142 to drive said pulley in the manner hereinafter to be described.

Means are provided to rotate the shaft 142' and the pulleys 134 to effect movement of the belts 129 in a clockwise direction from the position shown in FIG. 9.

To this end, as shown in FIG. 5, a substantially rectangular plate 151 is secured to the standard 69 and extends outwardly therefrom. Mounted on the plate 151 is a drive motor 152 which is connected through a universal joint 153 to said shaft 142. to drive the latter when said motor is energized.

Positioned immediately to the rear of the gauge and stop assemblies 71, as shown in FIG. 2, is a pair of pull rollers 154 mounted on vertically aligned horizontal shafts 155', at least one of which is driven and which serve successively to advance the box blanks to the succeeding equipment which, in the illustrative embodiment shown, comprises printing rollers 155.

In the illustrative embodiment shown in FIGS. 1 to 10, the advance of the box blank is controlled by rotation of a cam 156 mounted, for example, on one of the printing roller shafts 157.

Thus, as shown, the cam 156 has a protrusion which actuates the plunger of a micro-switch 158 with each rotation of the printing roller to control the actuator 93 so that the plunger 95 of the latter will move upwardly to release a single box blank in the manner hereinafter o be described.

Operation In the operation of the equipment, the guides 53 (FIGS. 6, 7) with the fins 65, are spaced along the support 52 so that the open box blanks may fit between the fins 65 with but little clearance, and the other guide 53, one or more of which may be provided depending upon the length of the open box blank, is spaced between the outer guides 53 and all the set screws 61 are tightened.

The belt assemblies 100 are positioned along the bars 66, 67 so that they will be located between the side edges or the box blanks to be fed and are then adjusted by turning knobs 121 so that the lower ends 123 thereof are spaced from the upper run 35 of belt 34 riding around rollers 32, 33 by a distance just slightly greater than the thickness of the box blank to be fed, so that but a single box blank at a time may pass thereunder, the blank immediately therea-bove being restrained by the said ends 123.

The hand wheel 48 is rotated to position the support 52 so that when a stack S of box blanks (FIG. 4) is positioned on the inlet end of conveyor belt 34, between the outer guides 53, the trailing edges 64 of the blanks will rest on the rollers '63 of the guides 53 and the leading edges 64' of the blanks will rest against the inclined outer run 131 of belt 132 and the inclined surface 163' of block 163 therebelow.

Suction is applied to the chamber 37, and the conveyor belt 34 and belts 129 are actuated.

As the upper run 35 of conveyor belt 34 moves to the left, as a result of the suction applied to the chamber 37, the leading portion of the lowermost box blank S will be securely retained against the conveyor belt 34 by reason of suction applied through the perforations thereof, and the stack of blanks above the lowermost blank will also be moved to the left. As the leading edges as of the blanks will abut against the outer runs 131 of moving belts 129, and the inclined portion 103/ as shown in FIG. 4, the leading edges 64' of the blanks will be moved downwardly. As a result, the leading edge of the lowermost box blank S will pass beneath the lower end 123 of the belt assembly and abut against stop fingers 86 which will restrain advance of such lowermost blank even 6 though the upper run 35 of the conveyor belt 34 is moving to the left.

Thereupon, the pull rollers 154 and the printing rollers 155 are energized.

As the cam 156 rotates, the projection thereon will momentarily actuate micro-switch 158 to correspondingly energize the actuator 93. As a result, its plunger will move upwardly to pivot the lever 85 in a counterclockwise direction from the position shown in FIG. 4 against the 'force exerted by coil spring 88. This will cause the lip =86 to be moved upwardly out of the path of movement of the leading edge 64 of the bottomrnost blank S of the stack, which will thereupon be advanced by the suction belt beneath said lip 86.

As the Spacing between the back stops 53 and. the gauge and stop assemblies 71 has desirably been adjusted to be less than the width of the blanks S, it is apparent that when the leading edges 64 of the blanks are abutting againstthe inclined portion of belt 12? the trailing edges 64 of the blanks will be supported by the back stop. As a result, the weight of the entire stack of blanks will not be supported by the conveyor belt, so that the pressure on the lowermost blank S will not be so great as to prevent ready movement thereof by the conveyor belt 34.

In addition, due to the plate 30, only a small portion of the upper run 35 of conveyor belt 34 will be effective to hold the box blank thereagainst. As a result, the rear portion of the next box blank S will not clamp the trailing portion of blank S against the conveyor, so that such blank S may readily be advanced.

The actuator 93 will then be de-energized and, due to the force exerted by coil spring 83, the lever 85 will be pivoted in a clockwise direction. However, as the blank S is directly beneath the lip 86, the latter will abut against the top of the blank, and the movement of the latter will be unimpeded and it will be advanced by the suction belt 34 between the pull rollers 154.

While such lowermost blank S is being discharged as shown in FIG. 4, the leading edge of the blank S immediately thereabove will be restrained by the lower ends 123 which are spaced from the conveyor belt 34 by a distance smficient to permit only one blank to pass thereunder at a time.

When the trailing edge 54 of the blank S has been moved past the lower ends 123, the second blank S will then be the lowermost blank, and its leading edge 64 will be forced downwardly beneath said lower ends 123 by the force exerted by the leading edge 64 of blank S immediately thereabove, which will be deflected downwardly by the outer run 131 of belts 129 which are moving in a downward direction reacting against the leading edges as of the blanks in the stack S.

Before the leading edge d4 of blank S can move any appreciable distance forwardly, since the trailing edge 64 of the blank 3 has been moved clear of lip 86, the latter will be moved downwardly under the urging of coil spring 88 against lever 85, into the path of movement of the leading edge 64' of blank S to restrain further advance of said blank.

Thus, the blank S will be advanced between the pull rollers 154 and then between the printing rollers 155 to be printed, and only when the printing has been completed and the cam 156 has been rotated 360 degrees to again actuate micro-switch 158 will the lever 85 again be pivoted to release the next blank S it is apparent that the lowermost blank will be positively moved by the suction belt against the lips 86 prior to release thereof, and hence will be squared, so that its subsequent movement will be without skewing. Since the pull rollers 154 will positively grip the blank and advance the latter to the printing rollers 155, which also positively grip the sheet, no skewing will occur and perfect printing will result.

In the embodiment shown in FIGS. 1 to 10, the actuator 93 controlling the pivoted lever 85 may be remotely controlled by a micro-switch controlled by a cam rotating in timed rotation with the printing rollers.

In some applications it is desirable to have a direct mechanical linkage to actuate the pivoted levers 85. To this end, the embodiment shown in FIG. 11 is provided, which is substantially identical to the embodiment of FIGS. 1 to 10, and corresponding elements have the same reference numerals primed.

Referring to FIG. 11, the pin 97 of each lever 85 is connected to one end of a link 161, the other end of which is pivotally connected as at 162 to one end of a lever 163 which extends through an opening 164 in plate 81 and is pivotally mounted midway between its ends to a boss 165 rigid with said plate 81. The free end of lever 163 mounts a cam follower or roller 166, which coacts with a cam 167 mounted on a cam shaft 168 extending over the conveyor belt transversely thereof. The cam shaft carries a gear 169 at one end, which through an idler gear 171 is driven by a gear 172, illustratively mounted on the printing roller shaft 157', the gear ratio illustratively being such that with each rotation of the printing roller 155' the cam shaft 168 will be rotated a corresponding amount.

Thus, when the high point 167 on the cam 167 engages the cam follower 166, it will pivot the lever 163 in a counterclockwise direction to lift the link 161 and hence pivot the lever 85 in a counterclockwise direction against the urging of coil spring 88' to move lip 86 out of the path of movement of the leading edge 64 of the lowermost box blank S.

Tliereupon, the operation of the equipment is as previously described.

When the high point of the cam 167 has moved away from the cam follower 166, due to the urging of coil spring 88 the lever 85 will be pivoted in a clockwise direction, and through the link 161 will pivot the lever 163 in the corresponding direction.

With the equipment above described, dependable advance of the box blanks, one by one, in a predetermined timed relation and without skewing, may be achieved. As the entire area of the bottommost box blank in the stack, once it has been moved away from the back stop, will be retained by suction against such conveyor belt, any warpage that exists in such blank will be overcome, with the result that no jamming will occur. Furthermore, the moving belts 12$ will take care of warpage, to ensure dependable feeding of the box blank beneath the lower edges 123.

It is, of course, within the scope of the invention to utilize the feeding mechanism to feed a predetermined number of box blanks, and this may be accomplished by retaining the lever 85 in its uppermost position, with the lip 86 spaced from conveyor belt 84 until a predetermined number of blanks has passed thereunder. The control for the actuator 93 in such case could be a counter C (FIG. 1) of any conventional type that counts the box blanks as they are advanced.

As many changes could be made in the above equipments, and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Equipment for successively discharging the bottommost blank of corrugated board from a stack of such blanks, in which the blanks are in substantially horizontal position, comprising a perforated conveyor belt positioned in substantially a horizontal plane having an inlet portion on which at least a portion of the bottom of such stack adjacent its leading edge rests, means to advance said belt, stop means above and adjacent said conveyor belt and movable toward and away from the latter, gauge means positioned between said stop means and said inlet portion of said conveyor belt and above and adjacent the latter, said gauge means permitting movement thereunder by said conveyor belt from the bottom of such stack of only a single blank at a time for abutment of the leading edge of such bottommost blank against said stop means when the latter has been moved toward said conveyor belt, means to actuate said stop to permit passage of the blank restrained thereby, means to create a suction through the perforations in said conveyor belt to react against a substantial portion of the undersurface of the bottommost blank of the stack to advance such blank, said suction also being provided at least directly adjacent said gauge means to react against the leading portion of the blank from its leading edge, whereby the leading portion of the blank including its leading edge will be dependably moved downwardly and securely retained by the suction against the conveyor belt for advance beneath said gauge means.

2. The combination set forth in claim 1 in which the gauge means has an inclined surface against which the leading edges of the blanks in such stack are adapted to abut to deflect such leading edges downwardly.

3. The combination set forth in claim 1 in which the gauge means has an inclined surface against which the leading edges of the blanks in such stack are adapted to abut, at least a portion of said inclined surface comprising a belt adapted to move downwardly to deflect such leading edges downwardly.

4. The combination set forth in claim 1 in which said stop means comprises a lever pivotally mounted on an axis extending at right angles to the path of movement of said conveyor belt, and resilient means reacting against said lever normally to pivot the latter in direction to urge one end thereof into the path of movement of such blank to define a stop.

5. The combination set forth in claim 1 in which said stop means comprises a lever member pivotally mounted on an axis extending at right angles to the path of movement of said conveyor belt, resilient means reacting against said lever member normally to pivot the latter in direction to urge one end thereof into the path of movement of such blank to define said stop, and the means to actuate said stop comprises an operating member connected to said lever member, means to raise and lower said operating member, the connection between said operating member and said lever member providing positive coaction of said operating member against said lever member when the operating member is raised to provide simultaneous movement thereof to move the stop out of the path of movement of the blank restrained thereby and permitting independent movement of said lever member with respect to said operating member when the latter is lowered.

6. The combination set forth in claim 5 in which one of said members has a pin rigid therewith and the other member has an elongated slot through which the pin extends, one end of said slot and said pin being in engagement when the operating member is raised for positive coaction of said members, said end of the slot when said operating member is lowered being movable away from the pin to permit independent pivotal movement of said lever member.

7. The combination set forth in claim 5 in which said lever member has a vertical elongated slot therein, said operating member has a pin at its lower end extending through said slot, said pin engaging the upper end of said slot when the operating member is raised for positive coacting of said members, said upper end of the slot when the operating member is lowered being movable away from the pin to permit independent pivotal movement of said lever member.

8. The combination set forth in claim 5 in which a cylinder is positioned above said lever member, a piston is slidably mounted in said cylinder and is operatively connected to said operating member.

9. The combination set forth in claim 5 in which a lever is provided pivotally mounted between its ends, said operating member is pivotally connected to one end of said lever, and means are provided momentarily to react against the other end of said lever to pivot the latter to raise the operating member.

10. The combination set forth in claim 5 in which a lever is provided pivotally mounted between its ends, said operating member is pivotally connected to one end of said lever and a rotatably mounted cam is provided having a portion thereof adapted momentarily to react against the other end of said lever to pivot the latter to raise the operating member.

-11. The combination set forth in claim 1 in which a support for the trailing edge of such stack is provided extending transversely across the conveyor belt and longitudinally spaced from said gauge means, means to effect relative movement between said support and said gauge means to adjust the spacing therebetween, said spacing defining the inlet portion of said conveyor belt, said sup port and said gauge means being positioned in operation of the equipment so that with the leading edges of the blanks of the stack abutting against said gauge means the trailing edges of the stack will rest on the support with the trailing portions of the blanks in the stack spaced from said conveyor belt.

12. The combination set forth in claim 11 in which means are provided to eifect movement of said support toward and away from said gauge means.

13. The combination set forth in claim 1 in which said suction means applies suction through said belt only adjacent the gauge means.

14. The combination set forth in claim 1 in which a plate is positioned beneath said conveyor belt and longitudinally spaced from said gauge means to restrain suction through said belt at the portion thereof riding on said plate so that the suction means will apply suction through the belt only adjacent the gauge means.

References Cited in the file of this patent UNITED STATES PATENTS 1,046,190 Huddleston Dec. 3, 1912 1,352,284 La Bombard Sept. 7, 1920 2,856,187 Burkhardt et a1. Oct. 14, 1958 2,956,801 Coakley Oct. 18, 1960 FOREIGN PATENTS 275,872 Germany July 1, 1914

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