US3466030A

US3466030A - Rotary feeder for gathering machines

Info

Publication number: US3466030A
Application number: US571576A
Authority: US
Inventors: Kermit E Swanson
Original assignee: RR Donnelley and Sons Co
Current assignee: RR Donnelley and Sons Co
Priority date: 1966-08-10
Filing date: 1966-08-10
Publication date: 1969-09-09
Anticipated expiration: 1986-09-09

Description

Sept. 9, 1969 K. E. swANsoN Filed Aug. 10, 1966 FIE ROTARY FEEDER FOR GATHERING MACHINES '7 Sheets-Sheet l Spt- 9, 1969 K. E. swANsoN 3,466,030

ROTARY FEEDER FOR GATHERING MACHINES Filed Aug. l0, 1966 '7 Sheets-Sheet 2 cz urti 72 FIL-3.1m 0 q m Lm POWER 01ml' R//V 6 MHCK/NE 5.4.0 .D L E Sept- 9, 1969 K. E. swANsoN 3,466,030

ROTARY FEEDER FOR GATHERING MACHINES Filed Aug. 10, 1966 '7 Sheets-Sheet 3 K. E. SWANSON ROTARY FEEDER FOR GATHERING MACHINES Sept. 9, 1969 7 Sheets-Sheet 4 Filed Aug. 10, 1966 Sept. 9, 1969 K. E. swANsoN RTARY FEEDER FOR GATHERING MACHINES Filed Aug. 10. 1966 Sept- 9. 1969 K, E. swANsoN l 3,466,030

` ROTARY FEEDER FOR GATHERING MACHINES Filed Aug. l0; 1966 7 Sheets-Sheet 6 Sept. 9. 1969 K. E. SWANSQN 3,466,030

ROTARY FEEDER FOR GATHERING MACHINES Filed Aug. 10, 1966 7 Sheets-Sheet 7 United States Patent O 3,466,030 ROTARY FEEDER FOR GATHERING MACHINES Kermit E. Swanson, Naperville, Ill., assigner to R. R. Donnelley & Sons Company, a corporation of Delaware Filed Aug. 10, 1966, Ser. No. 571,576 Int. Cl. B65h 3/06, 7/02 U.S. Cl. 271-71 14 Claims ABSTRACT OF THE DISCLUSURE Apparatus for intermittently feeding signatures into the signature supply box of a gathering machine, in which a large upper stack of signatures is supported upon a pair of spaced, driven rollers which may be rotated toward each other to collapse the bottom signatures in the upper stack in the supply box without creasing them. Means associated with the supply box senses whether the top of the lower stack is above a predetermined level, and interrupts rotation of the rollers when the top of the lower stack is above said level.

As is well known, in the bookmaking art, books, catalogues, etc., are commonly assembled by gathering machines in which signatures having the printed matter representing a plurality of pages in the finished book are gathered in the proper order for binding. Customarily, in a gathering machine a conveyor is provided which passes along a row of boxes each of which contains a plurality of signatures and a swinging jaw means is provided for withdrawing a single signature from the bottom of each box and placing it at a signature receiving station on the conveyor. Accordingly, the signatures in each box must be replenished from time to time.

As is well known in the art, it is necessary that the number of signatures in each box be limited so the total weight on the bottom signatures does not interfere with its proper feeding from the box to the conveyor by the swinging jaw. This factor requires that the boxes be refilled frequently; and this, in turn, requires the use of several laborers, each of whom is in charge of replenishing the signatures in as few as three or four boxes. It will be appreciated that the use of a great number of laborers in conjunction with the operation of a gathering machine is extremely expensive in terms of the cost of the labor and wasteful to the extent that the labor could be used elsewhere. The problem is aggravated for those commercial parties who produce such things as mail order catalogues, telephone directories, state statutes, and the like; because each is printed only once or twice a year, and each requires many more boxes of signatures than are needed for any other work in the shop.

It is, therefore, the principal object of the invention to provide a new and improved feeder for feeding signatures to a box of a gathering machine.

More specifically, it is an object of the invention to provide a feeder for feeding signatures to a position of a gathering machine including a hopper for receiving a stack of signatures, a pair of rollers located at the lower end of the hopper and supporting the stack of signatures therein, and a means for rotating the rollers toward each other to collapse the signatures in contact therewith so `that the signatures are fed seriatim downwardly between tures will be fed to the position to replenish the supply of signatures therein.

Still another object is the provision of a feeder such as that mentioned a'bove wherein the rollers have roughened surfaces that frictionally engage the signatures in the hopper to promote positive feeding thereof.

Still another object is to provide a feeder such as that mentioned in any of the preceding paragraphs wherein the hopper includes a front and a back and the signatures are adapted to be placed within the hopper with their fold ends at the front thereof, the rollers being constructed to rotate about axes which are perpendicular to the fold ends of the signatures.

Yet another object of the invention is to provide a feeder such as that mentioned in the preceding paragraph wherein the ends of the rollers adjacent the fold ends of the signatures are provided with pins projecting outwardly from the periphery of the rollers to further insure positive feeding of the signatures by penetrating the signatures.

Yet another object of the invention is to provide a feeder for gathering machines including a storage hopper; a pair of spaced rollers adjacent the lower end of the hopper for supporting a stack of signatures within the hopper; means for rotating the rollers toward each other to collapse and feed the signatures in contact therewith to a subjacent gathering machine box, the roller rotating `means including a continuously rotatable drive shaft, a

clutch, and power transmission means interconnecting the clutch `and the rollers to rotate the same when the clutch is engaged; detecting means for determining the level of signatures within the box of the gathering machine; and a means responsive to the detecting means for engaging the clutch to rotate the rollers and feed signatures to the box when the detecting means determines a need for signatures at the box.

Other objects and advantages will .become apparent from the following specification taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic side elevational View of a rotary feeder embodying the invention for replenishing signatures in a gathering machine box;

FIG. 2 is a schematic front elevational view of a rotary feeder and box;

FIG. 3 is a plan view of the feeder;

FIG. 4 is a side elevational view of the feeder with parts shown in section;

FIG. 5 is a fragmentary side elevational view of a part of FIG. 4, on an enlarged scale, showing details of a level sensing device used in conjunction with the feeder;

FIG. 6 is a front elevational view of the feeder on an enlarged scale;

FIG. 7 is a fragmentary vertical section taken substantially as indicated along the line 7-7 of FIG. 6;

FIG. 8 is a fragmentary plan view of a signature jogging device and additionally illustrates a portion of a shaker operating mechanism;

FIG. 9 is a fragmentary vertical section taken substantially as indicated along the line 9-9 of FIG. 8; and

FIG. 10 is a schematic of a control circuit for the feeder.

Turning now to FIGS. 1 and 2, a preferred embodiment of the feeding device 18 of the invention is seen to include a hopper generally designated 20 in which a plurality of signatures 22 are placed. As best illustrated in BIG. 2, the signatures 22 rest upon a pair of spaced rollers 24 which are disposed in a single plane with their rotational axes generally parallel just above a box,l generally designated 26, of a gathering machine. The length of the rollers 24 may be varied in accordance with the length of various sized signatures.

Signatures 22 are fed by the rollers 2-4 into the box 26 where they are ultimately supported by a gathering machine saddle 28. Any conventional means such as an arm and jaw may be used to extract signatures 22 from the box 26 by successively withdrawing the lowermost signature 22 and depositing it on a gathering machine conveyor (not shown).

The box 26 additionally includes a front plate 32; and a jogger, generally designated 34, is used to align the fold edges of the signatures against the front plate 32. Addrtionally, there is provided a shaker, generally designated 36, which aligns the heads and toes of the signatures within the box 26.

Finally, there is provided an adjustable sensing mechanism, generally designated 38, which is arranged to detect when the supply of signatures 22 within the box 26 falls below a predetermined level so as to actuate a mechanism including the rollers 24 for feeding additional signatures 22 from the hopper 20 to the box 26.

It is to be understood that a separate feeding device 18 is provided for each box 26 of a gathering machine.

As may be seen in FIG. 2, the rollers 24 support the stack of signatures 22 within the hopper by supporting the head end and foo-t end portions of the stack of signatures. When the rollers 24 are rotated in a direction toward the center of the stack of signatures 22, the signature directly in contact with the rollers 24 is collapsed and its central area is urged downwardly toward the box 26. When the signatures 22 are collapsed sufficiently to lose contact with the rollers 24, they fall to the subjacent box 26. The inherent resiliency of the signatures 22 causes them to return to a substantially fiat condition, and they are properly arranged within the box 26 by the jogger 34 and the shaker 36 so that they may be withdrawn by the arm 30 and fed to the conveyor of the gathering machine.

The mechanism for operating the rollers 24 is best seen in FIGS. 3, 6 and 7. Each roller 24 consists of a hollow cylinder 40 rotatably mounted on a shaft 41 (FIG. 7) by means of antifriction bearings. In the preferred embodiment of the invention, the outside diameter of the cylinder 40 is approximately 21/2 inches. One end 42 of the shaft 41 is received in a corresponding aperture (not shown) in the front plate 32 while the opposite end 43 of the shaft 41 is received in a corresponding aperture 44 (FIG. 6) in a vetrically disposed back plate 46 arranged near the rear of the box 26. In actuality, a plurality of the apertures 44 are provided in the back plate 46 for receiving the ends 43 of the shafts 41 supporting the corresponding rollers 24. A plurality of corresponding, aligned apertures (not shown) are also provided in the front plate 32 for receiving the respective shaft ends 42. As will be explained in greater detail hereinafter, the apertures 44 in the back plate 46 for receiving the shaft ends 43 and the apertures in the front plate 32 for receiving the shaft ends 42 are utilized to facilitate adjustment of the position of the rollers with respect to each other and with respect to the hopper 20.

Sprockets 48 are secured to the cylinders 40 adjacent the shaft ends 43, and

respective drive chains

50 and 52 are trained about the sprockets 4S, and into tensioning contact with respective idler sprockets 54. Each idler sprocket 54 is rotatably mounted on a stub shaft 56 which is received in an elongated slot 58 arranged diagonally in ythe back plate 46 in a direction generally transverse to the run of the respective cahins 50 and 52. Any conventional means such as a nut 60 may be used to retain the stub shaft 56 a-t a desired position within the slot 58 so that the positions of the idler sprockets 52 may be adjusted to take up slack in the

drive chains

50 and 52 as required.

The drive chain 50 is also trained about a drive sprocket 62 which is mounted on a rotatable shaft 64 on which a drive gear 66 is journalled, the latter being in mesh with a second drive gear 68 keyed to the output shaft 70 of a magnetic clutch 72. The output shaft 70 additionally mounts a drive sprocket 74 for the chain 52 and is rotatably journalled in bearings secured to the back plate 46.

The magnetic clutch 72 additionally includes an input shaft 76 which is suitably connected to the output shaft of a reduction gear box 78 which also have an input shaft 80 with a sprocket 82 mounted thereon, while a second sprocket 84 is mounted on a power shaft 86. It will be appreciated that the power shaft 86 may be common to all of the feeding devices 18 associated with the several boxes of the gathering machine and may be driven by any driven shaft in the gathering machine mechanism. A drive chain 88 is trained about the

sprockets

82 and 84 so that rotation of the power shaft 86, together with the engagement of the magnetic clutch 72 causes the roller 24 to be rotated in a clockwise direction by the chain 50 while the roller 24 is rotated in a countercloclcwise direction by the chain 52. As described previously in conjunction with the description of FIG. 2, this action causes the signatures in contact with the rollers 24 to be collapsed and fed to the subjacent box 26.

As best seen in FIG. 4, an idler sprocket 90 may be placed in engagement with the drive chain 88. The idler sprocket 90 is rotatably mounted on a shaft 92 which, in turn, is mounted on an arm 94. The arm 94 includes at the end thereof opposite the idler sprocket 92, a yokelike member 96 which surrounds a stationary shaft 98. The stationary shaft 98 is mounted on a support 100 which may additionally support the reduction gear box 78. The yoke-like member 96 includes a releasable securing means such as a screw, so the arm 94 may be secured against rotation relative to the shaft 98 in any of a plurality of positions whereby the idler sprocket 90 takes up slack in the drive chain 88 as required.

FIG. 4 additionally illustrates the surface characteristics of the rollers 24. Specically, each roller 24 is formed with a roughened signature engaging surface to insure a good frictional contact with the signatures 22. Typically, the desired surface characteristics of the rollers 24 may be provided by a conventional metal spraying process or by knurling, although some care must be taken to insure that the surfaces are not so rough as to damage the signature.

In the event it is desired that a more positive gripping Contact be made between the rollers 24 and the signatures 22, each roller 24 may have a plurality of pins 102 arranged about its periphery adjacent the shaft ends 42 for partially penetrating and gripping the signatures 22 adjacent their fold ends. Of course, the pins 102 can only be used where the signature is of the type where such perforations will be hidden or will be cut off in the finished product. Turning to FIG. 7, the manner in which the pins 102 are mounted on the rollers 24 may be seen. Specifically, each pin 102 is mounted on a threaded member 104 which may be received in a threaded bore 106 in the cylinder 40 comprising the roller 24. By rotating the member 104 within the bore 106, the degree of projection of the pin 102 beyond the periphery of the roller 24 may be regulated to suit the thickness of the particular signatures being fed.

The details of the hopper 20 will now be described.

As seen in FIG. l, the face plate 32 of the box 26 may be extended a substantial distance upwardly as indicated at 108. Guide means are spaced somewhat rearwardly from the extension 108 so as to guide the fold end of the signature 22 in a proper path with respect to the pins 102 on the rollers 24. As best seen in FIG. 3, the guide means 110 comprise a pair of generally L-shaped members providing signature fold end engaging plates 111 and signature head or foot end engaging plates 112.

Turning now to FIG. 2, the details of a spring mechanism associated with the signature engaging plates 112 may be seen. Specifically, a leaf spring 113 is vertically arranged on the inner face of the signature engaging plate 112. At the lower end of the signature engaging plate 112 there is provided a set screw 114 which is threaded in a nut 115 welded to the outer face of the plate 112. By suitable manipulation of the set screw 114 within its corresponding nut 115, the lower end of the correspending leaf spring 113 may be urged inwardly in varying degrees against the head or toe end of the signatures. The action of the spring 113 against the signature 22 is such as to aid the collapsing of the latter for feeding purposes as illustrated in FIG. 2. Thus, the spring 113 provides a preliminary collapsing effect before the signature is more completely collapsed by the action of the rollers 24.

Returning to FIGS. 3 and 4, securing means 116 which may be of any conventional nature are used to interconnect the guide means 110 and the extension 108 of the face plate 32. Preferably, the securing means 116 provide for an adjustment of the distance between opposing ones of the signature engaging plates 112. The spacing between the signature engaging plates 111 and the extension 108 of the front plate 32 is such that the signatures 22 will be guided into contact with the pins 162 at a position just inside the margin dened by the fold ends of the signatures 2.2.

The hopper additionally includes a pair of vertically arranged guide rods 118 for engaging the lap ends of the signatures 22. As best seen in FIGS. 3 and 7, the guide rods 118 are suitably secured as by welding to a horizontal bar 120 and have their lower ends terminating just above the upper surfaces of the rollers 24 (FIG. 7). Since the positions of the signature engaging plates 111 remain relatively fixed with regard to the rollers 24 and the front plate 32, it is necessary to provide a means for adjusting the position of the vertical guide rods 118 with respect to the front plate 32. Accordingly, the bar 120 receives a pair of set screws 122 in bores at its ends, the set screws 122 being passed through corresponding slots 124 in side plates 126. As best seen in FIG. 3, the side plates 126 are ixedly secured to the back plate 46 so the bar 120 and thus the guide rods 118 may be adjusted to and secured in any one of a plurality of positions at differing distances `from the front plate 32 by manipulation of the set screws 122, so the guide rods 118 will engage the lap ends of the signatures.

As will be appreciated by those skilled in the art, when signatures are loaded in the box 26, it is necessary that they be in abutment with the front plate 32. Additionally, because the fold end of a signature is generally stiffer than the lap end thereof, the latter tends to descend into the box 26 more rapidly than does the fold end when the rollers 24 operate to replenish the supply of signatures within the box 26. This characteristic of a descending signature may on occasion cause asignature to bridge within the box 26 so that its fold edge cannot descend properly to be engaged by the arm and jaw for extraction from the box 26.

Accordingly, means are provided for guiding the fold edge of a descending signature into substantial abutment with the front plate 32 and for retarding the descent of the lap end of the signature so that its rate of descent substantially matches that of the fold end of the signature. Specifically, as seen in FIGS. 3, 4 and 6, a pair of guide rods 130 are disposed below the rollers 24 adjacent the rear of the box 26. As best seen in FIG. 6, each guide rod 130 comprises a lower, vertical section 132 and an upper inwardly extending, diagonal section 134 terminating in a rearwardly directed, substantially horizontal stub 136. The lower ends of the vertically extending sections 132 are adjustably secured in apertures 138 of an elongated bar 140 by any suitable means. The bar 140 is, in turn, mounted on a shaft 142 which, as best seen in FIG. 4, is cantilevered from the downwardly extending portion of an angle iron 144 secured to the underside of a housing 146 for various parts of the mechanism including the clutch 72, the reduction gear box 78, the power shaft 86, etc. Means (not shown) are provided for fixing the bar 140 to the shaft 142 at any position along the length of the latter. Thus, the position of the guide rods 130 with respect to the front plate 32 and the height of the guide rods with regard to the rollers 24 may be adjusted in accordance with the requirement of a particular size slgnature.

In operation, the lap end of a signature descending from the hopper 20 by means of the feeding action of the rollers 24 encounters the stubs 136 and the upper diagonally arranged sections 134 of the guide rods 130 and has its descent retarded so that the fold end of the signature cornes to rest on the stack of signatures 22 within the box 26 at about the same time, or perhaps just before, the lap end of the signature contacts the stack of signatures within the box 26. Additionally, when the rods 130 are adjusted properly, the portions of said rods which face the front plate 32 abut the lap edges of the signatures 22 and cause the fold edges of the latter to be in substantial abutment with the front plate 32.

To aid in maintaining the orientation of the signatures 22 within the box, there is also provided a pair of side guidcs, (only one of which is shown) one for each side of the signature. Referring to FIG. 4, a block 150 is adjustably mounted on a shaft 152 which may extend the length of the gathering machine. From the lower end of the block 150, a side guide rod 154 extends inwardly through the front plate and downwardly to engage the head end or the toe end portions, as the case may be, of the signatures 22 within the box 26. The block 150 may be so positioned along the length of the shaft 152 as to orient the side guide rod 154 to abut the sides of the signatures within the box 26.

While the various guide means disposed within the box 26 perform an orienting function on the signatures 22 within the box 26, those skilled in the art will recognize that the effect of such guide means may not be sufficient to insure proper orientation. Accordingly, in order to insure that the fold end portion of each signature is in direct abutment with the front plate 32, the jogger 34, mentioned previously in conjunction with the description of FIG. 1, is provided. As best seen in FIGS. 4 and 9, the jogger 34 includes a substantially vertical paddle 156 which is driven in an oscillatory manner against the central area of the lap end portions of the signatures 22 to drive the fold end portions against the front plate 32. Oscillation of the paddle 156 is caused by an eccentric cam 158 mounted on 'the power shaft 86 and engaging a cam follower 160 disposed upon a shaft 162 journalled within a U-shaped yoke 164. The bight of the yoke 164 is extended to either side of the legs thereof as indicated at 166 and 168, the

extensions

166 and 168 in turn mounting a pair of push rods 170. Compression springs 172 are mounted on the push rods 170 and are interposed between the respective ones of the

extensions

166 and 168 and a surface of a stationary member 174 having bores 176 in which the push rods 170 are received. The ends of the push rods 170 opposite the

extensions

166 and 168 are secured to a bar 178 which, adjacent one end thereof and on its upper side, mounts a pair of set screws 180. Depending from the rear of the paddle 156, is a U-shaped ymernber 182 having legs bearing elongated slots 184 which are impaled by the set screws 180. The purpose of the just described construction is to allow for adjustment of the distance between the paddle 156 and the bar 178 to accommodate signatures of varying sizes and which may =be accomplished by loosening the set screws 180 and moving the paddle 156 to the desired position and then tightening the set screws 180.

It will be apparent from the above description that rotation of the shaft 86 and the associated cam 158 will cause oscillation of the cam follower and thus of the push rods 170. The connection of the paddle member 156 to the Ibar 178 causes transmission of the oscillation of the push rods to the paddle member 156. The springs 172 act to maintain the cam follower 160 in engagement with the cam 158 at all times.

The just described construction including the cam 158 and the push rods 170 is also used to impart an oscillatory motion to the shaker 36 which, it will be recalled, aligns the heads and toes of the signatures within the box 26. As seen in FIG. 8, the bar 178 includes an extension 190 terminating in a ball and socket joint 192 that connects with one end of an adjustable link 194, the other end of which is connected through a similar ball and socket joint 196 to an arm 198. As best seen in FIG. 6, the arm 198 is pivotally mounted intermediate its ends on a stub shaft 200 and bears at its end opposite the ball and socket joint 196 an inwardly extending diagonal cam surface 202. A cam follower 204 is disposed adjacent the cam surface 202 and is rotatably mounted on a shaft 206 between the legs of a U-shaped block member 208.

A first, upper shaft 210 is adjustably secured to the block member 208 within a bore 212 in the latter and extends through bushing 214 disposed in the upper ends of U-shaped member 216 which is secured to the frame of the gathering machine. The left-most end of the shaft 210 also adjustably mounts a block 218 by means of a bore 220 through the latter. Mounted on the upper surface of the block member 208 is an L-shaped member 222 which in turn mounts a paddle 224, while a similar L-shaped member 226 is disposed on the upper surface of the block 218 and mounts a similar paddle 228.

The shaft 210, at a point between the legs of the U-shaped member 216, mounts a collar 230, and a spring 232 is disposed about the shaft 210 and interposed between the left-most leg of the U-shaped member 216 and the collar 230 to urge the shaft 210 toward the right as seen in FIG. 6. Additionally, a second, lower shaft 234 is disposed within a bore 236 in the block member 208 and extends through a bushing 238 in the right-most leg of the U-shaped member 21'6 at a point somewhat below the bushing 214 to restrict movement of the block 208 to motion in a single plane.

Oscillatory motion is imparted to the

paddles

224 and 228 in the following manner. Reciprocating motion of the push rods 170 in the manner previously described causes the adjustable link 194 to reciprocate, thereby oscillating the arm 198 about the pivot provided by the shaft 200. As a result, the cam surface 202 on the arm 198 oscillates within a rotary path and in engagement with the cam follower 204. The cam follower 204 is continuously urged against the cam surface 202 by action of the spring 232. The diagonal orientation of the cam surface 202 causes a reciprocating motion to be imparted to the block 208 and thus to the shaft 210. As a result, the

paddles

224 and 228 will reciprocate, alternately engaging the head end portion of the signatures within the box 22 and then the toe end portions of the signatures 22 within the box 26. As mentioned above, the blocks 208 and 220 which ultimately mount the

paddles

224 and 226 are adjustably secured to the shaft 210 such that the distance between the two

paddles

224 and 228 may be varied to suit the dimensions of the particular signatures being used in the gathering machine.

In the event it is desirable to use the feeder while disabling the jogger 34 and the shaker 36, a latch means is provided for holding the cam follower 160 in a position out of engagement with the cam 158. As best seen in FIG. 8, a generally vertical stub shaft 240 is secured to the bight of the U-shaped yoke 164. A latch member 242 is pivotally mounted as at 244 to the stationary member 170 and includes a slot 246 for receiving the stub shaft 240. When the latch member 242 is swung into the position illustrated in FIG. 8, the entry of the shaft 240 into the slot 246 precludes reciprocation of the U-shaped yoke 164; and the arrangement is such that the cam follower 160 is spaced a distance from the axis of rotation of the shaft 86 a distance equal to or greater than the greatest radial dimension of the cam 158, thereby precluding movement of the follower 160 in accordance with the contour of the cam 158.

As previously mentioned, means are provided for sensing the level of the signatures 22 within the box 26 for controlling operation of the feeder. Referring to FIGS. 3, 4 and 5, a lifter swing shaft 250 extends along the entire length of a gathering machine and is oscillated through an arc of about 35 during the operation of the gathering machine.

Two sensing devices are provided for each feeder; and since the construction of each is identical to the other, only one will be described. A block 252 is fixed on the shaft 250 for rotation therewith. Depending from the block 252 is an elongated plate 254 having a slot 256; and a pair of microswitches 258 each having an actuator arm 260 is adjustably secured to the plate 254 by means of bolts 262 extending through the slot 256. Since the lifter swing shaft 250 is in a fixed position relative to the box 26, it will be apparent that the just described construction permits vertical adjustment of the microswitches 258 with respect to the box 26 so that each switch 258 may be positioned to sense any desired signature stack height within the box 26.

The nature of the oscillation of the lifter swing shaft 250 is such that when it is in its extreme clockwise position, the microswitches 258 are disposed in substantially the position illustrated in FIG. 4, while rotation of the lifter swing shaft to its extreme counterclockwise position locates the microswitches 258 substantially in the position illustrated in FIG. 5. It will be apparent that when the microswitches 258 are in the FIG. 4 position, the actuator arms 260 thereof may extend into the contines of the box 26 to contact the fold ends of signatures therewithin. If the level of signatures within the box 26 is below the level of the actuators 260, the positions of the actuator 260 to the microswitch 258 will not change. However, if the level of signatures 22 within the box 26 is above the level of the actuators, actuation of the microswitch 258 will take place.

The shaft 250 additionally mounts a control cam 262 which is oscillated with the shaft 250 to engage an actuator 264 of a microswitch 266 when the shaft 250 is in its extreme clockwise position.

The control circuit utilizing the switches 258 and the switch 266 will now be described. As seen in FIG. 10, a relay coil 270 is connected in series with the switch 266 and a switch 272 across a source of power 274. The switch 266 is normally open and therefore will only be closed when, as described above, the cam 262 on the shaft 250 rotates into contact with the actuator 264 of the switch 266. The switch 272 is an off-on switch for controlling the operation of a plurality of feeding units spaced along the gathering machine in that the relay coil 270 may include a plurality of contacts for operating a plurality of the clutch circuits, each clutch circuit being associated with a single feeder for a single box 26.

Power is also fed from the source 274 through a unit off-on switch 276 to a conventional magnetic clutch control unit 278. One of the outputs of the latter is connected directly to the magnetic clutch 72 while the other output is connected to the clutch 72 through the series combination of normally open contacts 270a operated by the relay coil 270 and the parallel combination of the switches 258 which are normally closed.

Power from the source 274 may also be fed to additional clutch control circuits (not shown) that are identical to that just described. In this respect, it is to be noted that but a single relay coil 270 is lrequired and may operate contacts 270b, 270C, etc., in such additional clutch control circuits as may be required. The function of the switch 276 is to provide off-on control of but a single unit as opposed to the plural unit olf-on control provided by the switch 272.

The operation of the circuitry just described is as follows. As will be appreciated by those skilled in the art,

each time a signature is withdrawn from the box 26, the

lifter swing shaft 250 will go through a complete period of oscillation. During this period of oscillation, the actuators 260 of the switches 258 will be swung into the box 26; and if the level of signatures within the box 26 is such as to block movement of the actuators 260 into the, confines of the box, the switches 258 will be opened. The cam 262 is positioned on the lifter swing shaft 250 such that it will engage the actuator 264 of the switch 266 to close the same only during the period `after the actuators 260 of the switches 25S have been swung into the box 26 and beforethey have been swung out of the box 26. Accordingly, when the switch 266 is closed by action of the cam 262 and the relay 270 energized to close the normally open contacts 270a, the clutch 72 will not be energized by the clutch control unit 278 because the switches 258 are open at this time. Thus, when the level of signatures 22 within the box 26 is above the level where replenishment is necessary, the clutch 72 will remain deenergized, and thus disengaged, and preclude operation of the rollers 24 to feed additional signatures 22 into the box 26.

If the level of signatures within the box 26 is suiciently low that additional signatures should be fed to the box 26, when the actuators 260 of the switches 258 are swung into the box, they will not encounter the fold edge 0f signatures therein and accordingly will remain closed. Thus, when the switch 266 subsequently closes to actuate the relay 270 and close the contacts 270a, the magnetic clutch 272. will be engaged and rotary power will be transmitted to the rollers 24 to feed additional signatures into the box 26. Since the switch 266 is closed only momentarily during each period of oscillation of the lifter swing shaft 250, it will be appreciated that the relay contacts 270a will only be closed momentarily thereby precluding the closed position of the switches 258 from con tinuously energizing the clutch 72 when the switches 258 are swung away from the box 26 by the lifter swing shaft 250.

It is to be noted that two of the switches 258 are preferably provided and are arranged in parallel with respect to one another. Thus, if either one of the siwtches 258 remains closed when its actuator 260 is swung into the box 26, feeding will take place. This feature is desirable in that each switch 258 acts as a back-up on the other switch 258.

From the foregoing, it will be appreciated that a feeder made according to the invention will properly replenish the signatures in a box of a gathering machine as required and may be suitably adjusted to suit any particlar signature size. In this respect, as a generalization, the roller axes may be located at a point approximately 273 of the distance from the vertical median plane of the signatures to the side edge of the signatures although the orientation may differ somewhat due to such factors as signature thickness, type of stock, etc. It will also be apparent that because of the large capacity of the hopper 20, a significant amount of manual labor may be eliminated because the automatic replenishing of the supply of signatures in the box by the apparatus is such as to meet the requirements of signature level control within the box while the number of signatures that may be loaded into the hopper 20 is independent of the maximum level of signatures permitted in the box 26. Accordingly, an extremely large number of signatures may be initially placed in the hopper 20 of the feeder and the feeder may operate in conjunction with the gathering machine substantially unattended as contrasted to the frequent manual replenishing of signatures in the boxes as required in prior art devices.

Having described a preferred embodiment of my invention as required by 35 U.S.C. 112, I do not wish to be limited to the construction set forth, but rather, to have Amy invention construed broadly according to its true spirit as set forth in the following claims.

I claim:

1. Apparatus for feeding signatures from the bottom of a stack downwardly onto a pile of signatures in a gathering machine box, said apparatus comprising, in

combination: a signature storage hopper having sides, a front and a back, and receiving a stack of signatures, a pair of spaced rollers `at the bottom of the hopper, said rollers being adjacent the sides of the hopper and supporting the head portion and foot portion of a stack of signatures in the hopper; means for rotating said rollers toward each other to collapse the signatures that are in contact with the rollers and feed them seriatim downwardly toward a pile of signatures in the gathering machine box; means for detecting the position of the top of the pile of signatures in the box; and means responsive to said detecting means for periodically rotating the rollers to add signatures to the pile.

2. The apparatus of claim 1 wherein said detecting means include a signature level sensing means and a means for periodically moving said sensing means between a nondetecting position -away from the gathering machine llox and a detecting position within the gathering machine 3. The apparatus of claim 2 further including means for rendering said roller rotating means inoperative whenever said sensing means are not in said detecting position.

4. The apparatus of claim 3 wherein said roller rotating means includes an electrically operable clutch, said sensing means comprises at least one switch in series with said clutch, and said means for rendering said roller rotating means inoperative includes electrical contacts in series with said switch and said clutch.

5. The apparatus of claim 1 including means for mounting said detecting means in a plurality of differing positions adjacent the gathering machine box whereby the detecting means may be selectively positioned to detect any desired level of the pile of signatures within the gathering machine box.

6. Apparatus for feeding signatures to the box of a gathering machine comprising, in combination: a storage hopper for receiving a stack of signatures and adapted to be positioned over the box of a gathering machine; a pair of spaced rollers adjacent the lower end of the hopper and adapted to support the stack of signatures within the hopper, said rollers having a surface promoting a substantial frictional contact with the signatures; means for rotating said rollers towards each other to collapse the signatures in contact with the rollers to feed the signatures downwardly, said roller rotating means comprising a con tinuously rotatable drive shaft, a clutch operatively `associated with said shaft, and rotary motion transmitting means interconnecting said clutch and said rollers; detecting means adapted to be associated with the gathering machine box for sensing the level of signatures therein to determine when signatures should be fed from said hopper by said rollers to the gathering machine box; and means responsive to a determination by said detecting means that signatures should be fed to said box for er1- gaging said clutch to cause said rollers to be rotated.

7. The apparatus of claim 6 wherein said detecting means comprise switch means mounted on an oscillatory shaft for movement toward and away from the gathering machine box, said switch means having an actuator for contacting signatures within the gathering machine box; and said clutch engaging means includes circuit means including said switch means and energizable` to engage said clutch.

8. The apparatus of claim 6 wherein said detecting means include switch means adapted to be associated with the gathering machine box and actuatable in response to the presence or -absence of signatures therein; and said clutch engaging means comprises circuit means including said switch means and energizable to engage said clutch.

9. Apparatus for forming from an upper vertical signature stack a lower vertical signature stack spaced from and aligned with said upper stack, said apparatus comprising: means for laterally supporting said upper stack; a pair of spaced parallel rollers for supporting the bottom of said upper stack; means for supporting the bottom of said lower stack; and means for rotating said rollers toward each other to collapse the bottom signatures in said upper stack contacting said rollers and feed said bottom signatures seriatim downwardly between the rollers, without creasing them, onto said lower stack.

10. Apparatus according to claim 9 additionally comprising guides forming part of said lateral support means for said upper stack having converging end portions adjacent said rollers for preliminarily bowing said bottom signatures of said upper stack ahead of said rollers.

11. Apparatus according to claim 9 in which said signatures are disposed with their folds extending transversely of said rollers, said apparatus additionally comprising means beneath said rollers for retarding the downward displacement of the lap sides of the signatures as the latter are fed onto said lower stack.

12. Apparatus according to claim 9 additionally comprising jogging means for vertically aligning the signatures in said lower stack.

13. Apparatus according to claim 9 additionally cornprising means for sensing the height of said lower stack operative to interrupt the rotation of said rollers whenever said height exceeds a predetermined level.

14. Apparatus according to claim 13 in which the supporting means for said lower stack is a gathering machine box.

References Cited UNITED STATES PATENTS RICHARD E. AEGERTER, Primary Examiner U.S. Cl. X.R. 271-23