CA2021791A1

CA2021791A1 - Handling signatures with side belts running at different speeds

Info

Publication number: CA2021791A1
Application number: CA 2021791
Authority: CA
Inventors: William P. Belden; James R. Wood
Original assignee: Individual
Current assignee: Baldwin Technology Corp
Priority date: 1989-07-24
Filing date: 1990-07-23
Publication date: 1991-01-25
Also published as: GB9016228D0; AU5975690A; GB2235436A

Abstract

HANDLING SIGNATURES WITH SIDE BELTS
RUNNING AT DIFFERENT SPEEDS

ABSTRACT OF THE DISCLOSURE
A stream of signatures which are effectively thicker along one edge than an opposite edge are conveyed in a stream so that the signatures pass from a substantially horizontal shingled condition to an edge-standing condition with the thicker edges of the signatures being upright and disposed on the same side of the stream. The edge-standing signatures move onto a consolidating conveyor where they are arranged more compactly. The signatures then pass onto an accumulating conveyor, which normally advances the signatures at a slightly slower speed than the consolidating conveyor. When enough signatures to make a bundle have passed onto the accumulating conveyor, the velocity of that conveyor is increased substantially, and the consolidating conveyor is momentarily stopped to produce a loose zone in the stream of signatures at the juncture of the consolidating and accumulating conveyors.
A sword is extended into the loose zone of the signatures and pushes the signatures on the accumulating conveyor forward to form a distinct gap in the signatures to the rear of the sword. Compression fingers extend into the gap behind the isolated signatures on the accumulating conveyor and push them forward. The compression fingers push the isolated bundle through a board drop assembly, where boards are placed at each end of the bundle.
Thereafter, the compression fingers compress the bundles between the boards so that a band may be secured around the boards and bundled.
Belts on each side of the signatures as they move along the consolidated and accumulating conveyors engage the upstanding edges of the signatures and assist them in moving forward. The belts on opposite sides of the signatures are operated at different speeds to compensate for skewing of the signatures induced by the thickening upstanding edges. This facilitates clean separation of the signatures with the sword. Preferably, the side belts along the accumulating conveyor are located at a lower level than any of the side belts disposed along the consolidating conveyor.

Description

19298:RWJ:ems -1-HANDLING SIGNATURES WITH SIDE BELTS
RUNNING AT DIFFERENT SPEEDS

BACKGROUND OF T~IE INVENTION
This invention relates to improved methods and apparatus for handling flexible sheets, or signatures, so they can be bundled.
U.S. Pat. No. 4,531,343 to Wood ~1985): U.S. Pat.
No. 4,641,489 to Wood (1987); and U.S. Pat. No. 4,824,093 to Belden ~1989) disclose machines for cavsing signatures deIivered from a printing press to rise ouk of a shingled condition and assume an edge-standing orientation as the signatures move as a stream along a path that leads away ~rom the press. While the signatures are in the edge-standing condition, the machine consolidates them, and then separates them into bundles by increasing the speed of a group of leading signatures to create a loose region betwaen that group of leading signatures and the remaining signatures. A separating member ("sword"~ is inserted into the loose region, and moved downstream to generate a distinct gap between the leading group of signatures and the rest of the stream. Compression fingers move into the gap and squeeze the isolated group of signatures into a compact bundle ~or binding and further handling.

1 The prior art machines work well for a stream of edge-standing signatures in which the upright side edges of the signatures are of substantially uniform effective thickness. However, when one upright edge is effectively thicker than the other, such as occur~ when one side of the signatures has "picker pin" holes formed as th2 signatures are taken from the printing press and folded.
The small amount of paper protruding at each hole causes the edge-standing signatures to assume an asymmetrical orientation relative to the centerline of the stream, and this interferes with a clean separation of the signatures as the sword moves into the loose region. A similar problem arises when the signatures are folded along one upright edge, and this invention solves the problem in either event.

SUMMARY OF THE INVENTION
The present invention provides improved methods and apparatus for controlling a stream of edge-standing signatures which are effectively thicker along one upright edge than another, so groups of the signatures can be automatically formed into bundles.
In terms of apparatus, the invention includes means defining a path for the stream of signatures and means for moving the signatures along the path from an upstream to a downstream location. First and second endless side belts are mounted on opposite sides of the path, and each extends substantially parallel to the path so that each belt has inner and outer flights. Separate means are provided for independently moving the first and second belts so that the inner flight of each belt moves in a downstream direction and engages respective upright edges of the signatures so the signatures are urged to move along the path in a downstream direction. Maans are provided for adjusting the relative speeds of the first 1 and second belts to control the relativ2 positions of the opposite edges of the signatures along the path.
In the preferred form of the invention, the side belt of the first and second belts contacting the thicker edges of the signatures runs faster than the other side belt. Preferably, one or more endless table belts are disposed between the side belts and are arranged to run so that each table belt has an upper and lower flight so that the upper flight engages the bottom edges of the edge-standing signatures as they travel between the first and second side belts.
The preferred form of the invention includes a third endless side belt mounted on the same side of the path as the first endless side belt and downstream from the first side belt so the third belt has inner and outer flights substantially parallel to the path. A fourth endless side belt is mounted on the same side of the path as the second endless side belt and downstream from the second side belt so that the fourth belt has inner and outer flights substantially parallel to the path downstream from the second endless belt. Means are provided for driving the third and fourth endless belts at different speeds relative to each other to control the relative positions of opposite edges of the signatures along the path. In addition, the third and fourth side belts each have upper and lower edges, and the lower edges of the third and fourth side belts are at substantially the same level as the lower edges of the edge-standing signatures.
In yet another preferred form of the invention, means are provided for mounting the third and fourth belts to diverge from each other in a downstream direction.
In a further preferred form of the invention, the apparatus includes a fifth endless side belt mounted above the first endless side belt and on the same side of the path as the first side belt so the fifth belt has 1 inner and outer flights substantially parallel to the path. A sixth endless side belt is mounted above the second endless side belt and on the same side of the path as the second endless side belt so the sixth belt has inner and outer flights substantially parallel to the path. A seventh endless side belt is mounted above the third endless side belt and on the same side of the path as the third belt. An eighth endless side belt is mounted above the fourth side belt and on the same side of the path as the fourth belt so the eighth belt has inner and outer flights substantially parallel to the path. The first, fifth, and seventh endless side belts are mounted to travel around a first common upright axis, and the second, sixth, and eighth endless side belts are mounted to travel around a second common upright axis. Preferably, the third belt is mounted to travel around a pair of longitudinally spaced upright axes downstream from the first common upright axis, and the fourth belt is mounted to travel around a pair of longitudinally-spaced upri~ht axes downstream from the second common upright axis.
Means are also provided for driving the third and seventh belts at one speed, and means are provided for driving the fourth and eighth belts at a speed different from that of the third and seventh belts.
In terms of method for controlling and moving a stream of edge-standing signatures along a path, the signatures being effectively thicker along one upright edge than another, which causes the signatures to shift into an asymmetrical orientation relative to the longitudinal axis of the path, the method includes the steps of moving the signatures along the path from an upright stream to a downstream location. A first endless belt engages the thicker upright edges of the signatures on one side of the path, and a second endless belt engages the upright edges of the signatur~s on the other side of 1 the path. The belts are moved at different speeds relative to each other to control the relative positions of opposite edges of the signatures along the path to reduce the tendency of the signatures to shift into an asymmetrical orientation. Preferably, the method includes the steps of engaging the thicker upright edges o~ th~ signatures with a third endless belt downstream ~rom the first endless belt and on the same side of the path as the first endless belt, and engaging the upright edges of the signatures with a fourth endless belt on the same side of the path as the sec~nd endless belt and downstream from the second endless belt. The first endless belt is moved faster than the second, and the third endless belt is moved faster than the fourth to make the signatures more nearly symmetrical with respect to the longitudinal path along which the signatures move.
These and other aspects of the invention will be more apparent from the following detailed description and the accompanying drawings.

.

FIG. 1 is a perspective view of a machine for handling signatures in accordance with the present invention;
FIG. 2 is a sectional view taken alsng line 2-2 of FIG. 1 showing the sword and compression fingers;
FIG. 3 is a view taken along line 3-3 of FIG. 2;
FIG. 4 is an enlarged viéw of the machine taken along line 4-4 of FIG. 2 showing restraining wings for momentarily holding the signatures as a gap i8 developed in the region of looseness;
FIG. 5 is a detail view of the mechanisms for mounting and moving the sword and the compression ~ingers:
FIG. 6 is a view taken on line 6-6 of FIG. 5;
FIGS. 7a-7i are a series of schematic views showing the sequence of operation of the machine of this invention as it separates edge-standing signatures into bundles and thereafter compacts such bundles;
FIG. 8 is a view of the right side belts taken on line 8-8 of FIG. 3;
FIG. 9 is a view taken on line 9-9 of FIG. 8; and FIG. 10 is a block diagram of circuits for controlling the apparatus shown in FIGS. 1-9.

Referring to FIGS. 1 and 7a-7i, a signature bundling machine 10 receives a stream of signatures 11 (FIG. 7a~
delivered to it in a shingled condition from a high-speed printing press (not shown). The machine advances the signatures in a downstream (from left to right as viewed in FIGS. 1-5, 7a-i, 8, and 9) direction along a substantially hori~ontal path 12 (FIG. 1), and initially in a shingled condition. As the signatures advance, they encounter a deflecting or orienting gate 12A on path 12.
The gate forces the signatures to rise to an edge-standing condition, with the major planes of the signatures substantially perpendicular to the direction of travel along the path. The width of the gate is slightly less than the width of the signatures so each signature is forced to assume a bowed condition around an upright axis, each signature being curved to present a forward-Eacing convex surface, as shown in FIG. 4. For the purpose of explaining this invention, each signature has "picker pin" holes (not shown) formed along its upriyht edge on the right (unless indicated otherwise, the terms "right"
and "left" refer to looking in the downstream direction) side of the stream. The holes are formed by picker pins (not shown) during the folding of the signatures. The holes extend along one side of each signature, and along a line perpendicular to the fold, or "spine", of the signature. The signature spine is normally the lower edge of the edge-standing signature, and the spine is perpendicular to the direction of travel. The upright edge of each signature with the picker pin holes is effectively thicker than the opposite edge without th~
holes because of the small paper tabs 12B (FIG. 4) protruding at each hole. The cumulative effect of the paper tabs tends to cause the signatures to become skewed and assume an asymmetrical orientation with respect to 1 the direction of signature travel. Unless carrected, as described below, the asymmetry interferes with automatic separation and bundling of the signatures. As indicated above, the same problem arises when each signature includes a fold along an upright edge.
~ s the bowed signatures advance along the path, they are consolidated, i.e., caused to move more closely together. After enough edge-standing signatures have been accumulated, the machine separates some of the signatures from the remainder to form an isolated, loose bundle 13 (FIG. 7c), which advances separately, having end boards 14 placed against its ends. The loose bundle is thereafter compressed and tied with a strap 15 (FIG.
7h) from a strapper (not shown), which may be of conventional type.
The signature bundling machine 10 includes a frame 16 which supports a receiving conveyor 17, a consolidating conveyor 18, and an accumulating conveyor 19, all in that order to form the path 12 along which the signatures advance. At the downstream end of the receiving conveyor 17, the frame supports the gate 12A which causes the signatures, as they advance along the path 12, to rise from a substantially horizontal shingled orientation to the edge-standing orientation.
A separating assembly 20 (FIG. 2), described in more detail below, is mounted on the frame 16 in the vicinity of the accumulating conveyor 19. The separating assembly causes some of the leading signatures accumulatad in the edge-standing condition along the accumulating conveyor to separate from the following signatures to produce the loose bundle 13 shown in FIGS. 7c and 7d. The separating assembly advances that loose bundle at a greater velocity to a compression unit 21, which is mounted on the frame 16 adjacent the path of the signatures. As explained in 3~ more detail below, the separated signatures of the loose 1 bundle are compressed and tied to form a compact bundle.
The frame also supports an end board drop assembly 22 for placing one end board 14 ahead of the signakures as they accumulate on the accumulat~ng conveyor 1~ and another end board at the trailing end of the signatures in the separated bundle, so the bundle has a rigid end board at each end.
The receiving conveyor 17 includes four parallel endless table belts 23 (FIGS. 1 and 3) arranged side-by-side with respective upper flights or passes 23A horizontaland disposed to carry the shingled signatures. Preferably, the outer surfaces of the belts 23 have transverse ribs (not shown) to grip the trailing edges of the signatures and move them onto the consolidating conveyor 18. The belts 23 pass over pulleys (not shown) mounted on horizontal shafts 23B and 24 in bearings (not shown) supported by the frame. The shaft 24 at the discharge end is powered.
The consolidating conveyor 18 has three horizontally spaced and parallel endless consolidating table belts 26 (FIGS. 3, 4, and 9) located side-by-side and passing around pulleys (not shown) at the ends of the consolidating conveyor 18. The pulleys at the discharge end of the consolidating conveyor are moun~ed on a powered horizontal and transverse shaft 28. The pulleys for the consolidating table belts 26 at the inlet end are mounted to free-wheel on the power shaft 24 so that each upper pass of the consolidating belts 26 is between adjacent upper passes of the table belts 23, and thus form a smooth extension of the upper passes of the table belts 23 of the rsceiving conveyor.
Power shaft 28 turns somewhat slower than power shaft 24 so that the belts 26 of the consolidating conveyor move slower than the belts 23 of the receiving (gate) conveyor. This causes the signatures to pack more closely 1 together, or to consolidate, after leaving the receiving conveyor 17. The transition of the signatures to the lower speed of the consolidating conveyor belts 26 is gradual.
Therefore, the belts 26 must be free to slip slightly with respect to the lower edges of the signatures, at least in the upstream region of the consolidating conveyor 18. Therefore, the outer surfaces of the consolidating belts are relatively smooth.
In addition to the consolidating table belts 26, the consolidating conveyor 18 also includes two vertically-spaced endless side consolidating belts 30 (FIGS. 1-4) on each side of the signature path to form the sides of the consolidating conveyor. The endless consolidating side belts 30 each pass around respective pulleys 31 on vertical upstream powered shafts 32 and downstream idler shafts 34, each of the former being powered by separate respective left and right variable-speed stepper motors 35 and 35A
(FIG. 9), each motor being connected by a respective gear box 35B (only the right gear box is shown, and that is in FIG. 8) to the upper end of powered shafts 32. The pulleys 31 on the powered upstream vertical shafts 32 are fixed to and driven by those shafts at speeds independently determined by the left and right stepper motors. The pulleys 31 on the idler downstream vertical shafts 34 rotate freely on those shafts. Ordinarily, the inner passes of the side belts 30 and the upper passes of the table belts 26 in the consolidating conveyor 18 move at about the same speed, except that the left and right side belts can be run at speeds slightly different from each other and from that of the ta~le belts, when required to compensate for any signature asymmetry which arises from one upright edge of the signatures being of an effective thickness difrerent from that of the other edges. Moreover, the lower edge of each lower side consolidating belt is at substantially the same level as the top surface of the 1 consolidating table belts to provide better control of the edge-standing signatures as they move downstream. The vertical idler downstream shafts 34 and the horizontal power shaft 28 are at about the same location along the path 12. The vertical powered upstream shafts 32 are spaced somewhat downstream from the common shaft 24 of the receiving and consolidating conveyors 17 and 18. As a consequence, the consolidating side belts 30 are shorter than the consolidating table belts 26. Thus, when the signatures move onto the consolidating conveyor 18, they âre initially advanced only by the consolidating table belts 26, but thereafter they come in contact with the consolidating side belts 30, which engage the upright edges o~ the signatures and assist the table ~elts 26 in advancing the signatures. I
The table belts 23 of the receiving conveyor 17 are powered by a first gear motor 36 (FIG. 2) carried by the frame 16 and coupled (by conventional means, not shown) to the horizontal shaft 24. The table belts 26 of the consolidating conveyor are driven by a second gear motor 37 (shown only in block form in FIG. 10) coupled ~by conventional means, not shown) to power shaft 28.
The accumulating conveyor 19 includes a hori~ontal, flat skid plate 38 (FIGS. 2, 3, and 4) which forms an extension of the path 12 from the table belts 26 of the consolidating conveyor. The accumulating conveyor 19 also has three vertically-spaced, endless side belts ~0 along each side of the path 12 and adjacent the skid plate 38. The top two accumulating side belts 40 each pass around idler pulleys 41 (FIG. 8) carried by the vertical idler shafts 34 for the downstream end of the consolidating conveyor, and around pulleys (not shown) rigidly mounted on powered left and right vertical shafts 42, 42A, respectively, at the downstream end of the accumulating conveyor 19. The lowest accumulating side belts 40 of 1 the three on each side of the signature path each pass around re~pective driven pulleys (not shown) fixed to the powered vertical shafts 42, 42A, and around idler pulleys 43 mounted to rotate freely on vertical idler shafts 43A
mounted in line with vertical shafts 32, 34, and 42, but located just downstream of the vertical shafts 34. This arrangement permits the lower edges of the lowest accumulating side belts 40 to be substantially at the same level as the top surface of the flat ski~ plat 38, which is also at the same level as the top surface of table belts 26 and the lower edges of the lower side belts 30.
By having the lower edges of the lowest side belts along the sides of the consolidating and accumulating conveyors at virtually the same level as the table belts 26 and flat skid plate 38, control of the signatures is improved because the lower (folded) edges of the edge-standing signatures are at that level.
The pulleys for side belts 40 on the idler shafts 34 and 43A rotate freely with respect to that shaft, but the pulleys on each power shat 42 and 42A are driven by those shafts, and that motion is such that the belts 40 normally move at a speed slightly less than that of the table belts 26 and side belts 30 of the consolidating conveyor lB. The inner passes of the left and right side belts 40 move away from the consolidating conveyor 13.
Each powered left and right vertical shaft 42, 42A is coupled through a respective gear box 44 to a respective left and right d.c. servo motor 44A, 44B, respectively, which normally drive the belts 40 slower than the belts 26 and 30 for the consolidating conveyor. Each servo motor is independently controlled as described below with reference to FIG. 10 so the side accumulator belts 40 on one side of the path 12 can be driven at a speed different from those on the other side, and so the belts on both 3~ sides can be speeded up or slowed down on command. A

1 separate tachometer 44C (FIG. 10) monitors the speed of each side motor 44A and 44B, and sends a servo signal to a separate respective d.c. servo controller 44D for each side motor (shown in FIG. 10) to maintain the required speed for each motor. For example, after a sufficient number of signatures are on the accumulating conveyor, the accumulating side belts are momentarily speeded up so the signatures on the accumulating conveyor 19 move away from the signatures on the consolidating conveyor 18, creating a loose region 44C in the signatures (FIG~ 7c).
At the same time, the left and right stepping motors 35 and 35A and gear motor 36 are momentarily stopped to stop the belts 26 and 30 of the consolidating conveyor 18.
The purpose of this oparation is described in detail below.
As shown in FIGS. 1, 2, 3, 8, and 9, the right and left vertical idler shafts 34 are each journaled through the downstream end of respective horizontal upper and lower consolidating conveyor left and right plates 45, respectively, and through the upstream ends of horizontal and longitudinally extending upper and lower accumulating left and right plates 46, which are supported on the right and left sides of the skid plate 38. The downstream end of the consolidating conveyor plates 45 and the upstream ends of the accumulating conveyor plates 46 are each notched and shaped so that the upper and lower accumulator plates 46 on each side of the machine can pivot in a horizontal plane about the vertical axes of the respective vertical idler shafts 34, and relative to the upper and lower consolidating conveyor plates 45 to which they are connected. The downstream end of each lower accumulating conveyor plate 4~ is provided with a slot-and-bolt arrangement (not shown), which permits the accumulator conveyor plates 46 to be set and locked into any desired position to accommodate signatures of different widths.

~14-1 Thus, the right and left side belts of the accumulating conveyor ~an be set to be either exactly parallel to the longitudinal axis of path 12, or to diverge slightly outwardly by a few degrees from each other in a downstream direction to permit the bowed signatures to return gradually toward their normally flat condition as they are moved downstream by substantially parallel left and right side belts through the accumulating conveyor.
As stated above, the orienting gate 12A at the discharge or downstream end of the receiving conveyor 17 causes signatures, as they pass through the gate, to rise from the shingle orientation to an upright or edge-standing orientation, as shown in FIG. 7a. The signatures are dPlivered from the printing press (not shown) on a feed conveyor 50 (FIGS. 1 and 3) positioned at a right angle to the right side of the receiving conveyor 17. The discharge end of the feed conveyor 50 is slightly higher than the adjacent inlet end of the receiving conveyor 17.
The feed conveyor 50 discharges the signatures onto the receiving conveyor, and against an upright bump plate 52 on the opposite side of the receiving conveyor. On striking the bump plate, each sheet drops and accumulates in a pile at the inlet end of the receiving conveyor (FIG.
7a). The pile of signatures rests on the upper passes of the horizontal table belts 23 for the receiving conveyor.
As the belts move, they withdraw signatures one after the other from the bottom of the pile. However, before the belts 23 completely withdraw the lowermost sheet from the bottom of the pile, the belts come in contact with the sheet immediately above the lowermost sheet, and enough friction develops between the second lowermost sheet and the belts to cause it to withdraw as well. As a conse~uence, th~ signatures leave the stack in a tightly-shingled condition and advanca toward the orienting gates in that condition.

1 The speed of the horizontal table belts 23 in the receiving conveyor 17 is regulated in response to a signal developed by a pile height sensor 53 (FIGS. 1, 2, 3, and 10) in the form of a first rotary variable differential transformer (RVDT), which may be of conventional construction, mounted at the inlet end of the receiving conveyor. A paddle 53A rides on the uppermost signature of the pile of signatures on the receiving conveyor. A
lever arm 53B connects the paddle to the first RVDT 53.
If the pile of signatures on the receiving conveyor becomes too high, say, because of increased output from the printing press (not shown), the paddle 53A rises and causes the lever arm 53B to adjust the first RVDT to a position which generates an electrical signal that causes the speed of the gear motor 36 to increase, and thus speed up the receiving conveyor belts 23 to move signatures downstream at a higher rate until the paddle 53A returns to the normal level. If the printing press slows down from its normal speed, the paddle 53A moves down and causes the first RVDT to generate a signal which decreases the speed of gear motor 36 and receiviny conveyor belts 23 so that the stack of signatures on the receiving conveyor builds up to the level called for by the setting of paddle 53A.
Tha signal from the first RVDT is proportional to the displacement of the paddle 53A so that when a larga correction is required, the speed of the gear motor 36 changes accordingly to minimize the time lag required to maintain optimum height of the s~ack of signatures at the inlet end of the receiving conveyor 17.
~he deflecting or orienting gate is, in effect, two deflecting plates 54, one on each side of the receiving conveyor 17 (FIG. 3). Th~ deflecting plates are spaced apart at a distance less than the width of the signatures and serve as an orienting unit which causes the signatures to change from a stream of shingled signatures to one of 1 edge-standing signatures. The upstream ends of the plates 54 have sloping surfaces 56 (FIG. 2) which face generally upwardly and inwardly, and are inclined upwardly in the direction of the advance of the signatures. As the signatures move up against the plates 54, their side edges ride up onto the sloping surfaces 56, causing the signatures to bow forwardly. The distortion tends to propagate upstream so the signatures ahead of the gates also bow slightly, but the bow diminishes and does not exist at the pile where the signatures first accumulate on the receiving conveyor 17. As the signatures bow forwardly at the sloping surfaces 56 on the deflecting plates, they are driven further into the gate by the underlying belts 23 of the receiving conveyor, the ribs of which engage the trailing edges (spines, in the example herein) o~ the signatures. As a consequence, the signatures move into the space between the two plates 54, their side edges wiping against the converging surfaces of the plates 54. Thus, the forward bow remains in the signatures at the plates 54 and increases as the signatures move forward.
The bowing, coupled with the application of the propelling force at the trailing edges of the signaturas, causes the leading edges of the signatures to rise gradually. By the time a sheet reaches the downstream end of the converging space between the two deflecting plates 54, the sheet is standing on edge, but because of ths shingled array, the edge-standing signatures are not yet well consolidated. Instead, they are spaced at approximately the former shingle width. Thus, as the signatures emerge from the orienting unit in an edge-standing or upright condition, they are still loosely consolidated and pass onto the consolidating conveyor 18 in that condition.
The deflecting plates 54 extend downstream to about the axis of the drive shaft 24, which is common to the receiving and consolidating conveyors 17 and 18. The 1 downstream edges of the plates 54 have vertical margins to which holding plates or clamps 60 (FIGS. 1, 2, and 3) are attached by vertical piano-type hinges (not shown).
In one form of the invention air cylinders 62, controlled by a solenoid valve 63 (shown only in block form in FIG.
10), urge the holding plates inwardly into the path of the signatures as a newly-starked array of signatures approaches the orienting unit. Thus, the leading edge-standing signatures of an array will not topple forward on emerging from the space between deflecting plates 54 of the orienting unit. Instead, the edges of the signatures bear against the holding plates 60, which at this time lie in the path of the signatures. The leading signatures tend to consolidate against the holding plates, but when enough signatures collect at the upstream sidP of the de~lecting plates, they lift a paddle 64 disposed over the consolidating conveyor. A lever arm 65 connects the paddle 64 to a gate area stream height sensor 66 in the form of a second rotary variable differential transformer, which generates an electrical signal that actuates the solenoid valve 63 to cause the air cylinders 62 to permit the plates to move to the full-open position shown in FIG. 3 so the accumulated signatures may pass.
Alternatively, and in the presently preferred embodiment, the holding plates 60 are controlled by turning a horizontal transverse shaft (not shown) under the path 12 in the vicinity of the plates 60. The transverse shaft carries right- and left-hand threads so that when it is rotated by a stepper motor 61 (FIG. 10) in one direction, the plate~ move into path 12, and when the shaft is rotated in the other direction, the plates move outwardly to the full open position shown in ~IG. 3.
The signatures force the holding plates 60 outwardly against stops (not shown), which align the plates with the inner passes of the side belts 30 for the consolidating 1 conveyor 18. The side edges of the edge-standing signatures slide along the plates 60 as the signatures pass from the constriction formed by the deflecting plates 54 to the left and right side belts 30 of the consolidating conveyor 18. Thus, the holding plates establish the signatures in a bowed condition (i.e., bowed convex forward) within th~ upstream region of the consolidating conveyor, as shown in FIG. 4. This keeps the signatures upright on the table belts 26 for that conveyor.
The inner passes of the consolidating conveyor left and right side belts 30 are spaced apart a distance slightly less than the width of the signatures, and that distance generally equals the distance between the holding plates 60 when the plates are spread outwardly and aligned with the side belts 30. Thus, the signatures remain bowed forwardly between the side belts 30 for the full length of the consolidating conveyor 18.
The consolidating conveyor 18 supports an aligning unit 67 (FIG. 2) which includes a horizontal plate 68 over path 12, and extending from over the space between the two deflecting plates 54 of the orienting unit over to the space between the side belts 30 of the consolidating conveyor. When unrestrained, the horizontal plate 68 is loosely suspended at an elevation slightly higher than the holding plates 60, yet is not so high as to avoid contact with the signatures, which project slightly above the upper edges of the holding plates. A vibrator 70, secured to the upper surface of the horizontal plate 68, causes that plate to vibrate up and down. As the signatures move through the downstream ragion of the orienting unit, where the gate is formed by the deflecting plates 54, and pass into the initial region of the consolidating conveyor, the signatures pass beneath the vibrating horizonal plata 68 which rides on the upper adges of the signatures. The vibrating plate bounces against the upper edges of the bowed 1 signatures and forces the highest signatures down, so that the upper edges are forced into a substantially horiæontal common plane before the signatures are more tightly compacted downstream.
Restraining wings or clamps 72 (FIGS. 2 and 4) at the downstream end of the consolidating conveyor 18 are movable between retracted and extended positions. When extended, ; the wings 72 lie in the path of the signatures at the location where they transfer from the consolidating conveyor 18 to the accumulating conveyor 19. When retracted, the wings 72 lie between the side belts 40 at each side of the accumulating conveyor and do not interfere with the movement of the signatures along that conveyor. The wings 72 pivot about respective vertical pins 74 on the accumulating conveyor 19 and are each connected to respective air cylinders 76, which cause the wings to move between the extended and retracted positions. The wings 72 have relatively flat vertical surfaces which face the signatures when the wings are extended, and axtend downstream and inwardly at an angle of between about 30~ and about 45 with rPspect to the direction of advance.
The signatures moving along the path bow forward so that the midportion of each signature leads its side edges (FIG. 4). Thus, the midportions pass onto the accumulating conveyor 19 first, but in doing so, they encounter only the skid plate 38, which exerts no propulsive force. The trailing side edges of the signa~ures are in contact with the side belts 30 of the consolidating conveyor, and those belts continue to driva the signatures forward. With the wings 72 retracted, the side edges of the signatures merely pass to the side belts 40 of the accumulating conveyor 19, where they move forward at a somewhat slower speed and, therefore, move more closely together. Thus, a continuous array of signatures normally exists along the consolidating and accumulating conveyors.

1 However, when the wings 72 are extended, the side edges of the advancing signatures at the end of the consolidating conveyor 18 do not contact the side belts of the accumulating conveyor 19 but, instead, are intercepted by the wings 72, the leading signatures being urged against the wings 72 by the continued advancement of the signatures.
The wings 72 remain extended for only a short duration, and only when the speed of the accumulating conveyor 19 is momentarily increased to advance a loose bundle 13 to the compressing unit 21 ~FIGS. 7d and 7e). The two side edges of any signature usually are not precisely at the same point of advancement along the path. This is especially true when the signatures include picker pin holes along one upright edge o~ the signatures. For the purpose of explaining this invention, it is assumed that the picker pin holes are formed along the right edge of the signatures. Accordinglyl the effective thickness of the right edges of the signature is greater than the opposite edge, which has no picker pin holes. The cumulative effect of the small amount of paper tabs 12B
(FIG. 4) protruding at each picker pin hole causes the right side of the signatures to "fan" out with respect to the left side, and this causes the picker pin side (right? of each signature to lag the opposite side as the signatures pass the plates 60. To correct for this effect, the right side belts of the consolidating conveyor run slightly faster than the left side belts of the consolidating conveyor to make the signatures more symmetrical with respect to the centerline of the signature path 12 by the time the signatures reach the end of the consolidating ~onveyor. Typical speeds while running signatures with picker pin holes on the right side would be as follows:
the receiving conveyor table belts 23 run at about 2.25 in./sec.; the consolidating conveyor table belt runs at about 0.50 in/sec.' the left side belts of the consolidating 1 conveyor run at about 0.46 in/sec.; and the right side belts of the consolidating conveyor run at about 0.54 in./sec.
When a loose bundle 13 is to be formed by increasing the speed of the accumulating conveyor (as described in detail below), the wings 72 are extended into the path to prevent the signatures at the transition between the consolidating conveyor and the accumulating conveyor from being propelled by the side belts 30 and 40 when they are operated at two substantially different speeds, such as is required to effect the separation of the signatures.
Ordinarily, the right and left side belts 40 of the accumulating conveyor run at slightly slower speeds than the side belts and table belts of the consolidating conveyor so that the signatures remain in a relakively compact condition. However, the left side belt o~ the accumulating conveyor runs at a slightly higher speed than the right side belts of that conveyor to correct the tendency of the right side of the signatures to fan out in a downstream direction (i.e., the right or thicker edges of the signatures tend to move ahead of the left edges of the signature, so that the signatures will be more nearly symmetrical with respect to the longitudinal axis of the path 12 by the time they reach the downstream end of the accumulating conveyor. For example, the left side belts of the accumulating conveyor in a typical operation run at about 0.3~ in./sec., and the right side belts of that conveyor run at about 0.25 in./sec.
When a loose bundle 13 is to be formed, the side belts 40 of the accumulating conveyor are momentarily speeded up, say, to about 2.5 in./sec., and the wings or clamps 72 are extended into the path 12 to engage the side edges of the signatures at the downstream end of the consolidating conveyor, and thus provide a cleaner ~5 separation of the last signatures in the loose bundle 1 from those which still remain at the downstream end of the consolidating conveyor. This operation is described in more detail below.
The separating assembly 20, which, for the most part, lies beneath the accumulating conveyor 19, intermittently causes a separation in the array of signatures that pass through the accumulating conveyor 19 and onto the compression unit 21 so as to isolate a portion of the signatures in the form o~ a loosely-compacted bundle 13 (FIGS. 7c-7g). When energized as described below, consolidating conveyor belts are momentarily stopped, and the right and left side belt motors of the accumulating conveyor are speeded up momentarily to a speed of about 2.5 in./sec. to create looseness in the succession of signatures at the transition between the consolidating conveyor and the accumulating conveyor (FIGS. 4 and 7c).
The wings 72 are extended into path 12, as shown in FIG.
4, and engage the upright edges of the signatures immediately behind the last signature to be moved forward by the accelerated side belts 40 of the accumulating conveyor.
An elongated, longitudinally extending slot 88 in the horizontal skid plate 38 opens out of the rear of the skid plate. A vertical sword 90 is mounted on an endless, reversible belt 91, which travels longitudinally under the slot 88. The sword (shown in more detail in FIGS. 5 and 6) is extendible to an upward position into the path of the signatures and is retractable to a lower position ~out of the path of the signatures. The sword 90 is extended ; 30 or elevated into the signatures after the region of looseness 44C (~IGS. 7c and 7d) has been created by momentarily speeding up side belts 40 so that the sword will not dislodge any signatures from the path or tear them. The sword elevates at the upstream end of the slot (the home position of the sword), and then moves forward, 1 being carri~d by the endless belt 91. The sword and sid~
belts 40 drive the signatures on the accumulating conveyor forward a short distance, and the endless sword belt 91 stops. This creates a distinct gap in the succession o~
signatures, with all signatures downstream from the gap constituting the loose bundle 13 (FIG. 7c). As the sword moves forward, the wings 72 remain in the path to restrain the signatures to the rear of the gap and the sword. A
few of the signatures are held at their edges by the wings 72, while the center portions of those signatures are on the downstream side of the sword, as shown in FIG.
4. When the sword moves downstream, it pulls those few signatures free o~ the wings so those signatures form the upstream end of bundle 13.
To provide the vertical and horizontal motions for the sword 90, it is mounted to slide in a vertical piston mounted by a horizontal transverse pivot pin 93 to a bracket 94 secured to the endless belt 91, which is driven in the forward and reverse directions by a sword motor 95 (FIGS. 5 and 10) connected to one of two pulleys 96 secured to the machine frame and about which the endless belt 91 travels. A tension spring 97, secured at one end to the belt 91 and at its other end to the lower end of the piston 92, urges the piston to pivot in a counterclockwise direction (as viewed in FIG. 5), causing a proximity switch 98 mounted on the sword belt to be in a normally open position. The proximity switch closes when the sword is engaged by advancing signatures to the rear o~
the gap, causing the sword piston 92 to pivot in a clockwise direction (as viewed in FIG. 5). This causes the sword motor 95 to advance the sword at a rate approximately equal to that o~ the signatures behind the sword so the sword supports those signatures and keeps them from falling forward. This operation is described in more detail below.

1 A pair of vertical and laterally spaced compression fingers 106 are each mounted in a respected finger piston 107 secured to a carriage 108 mounted to travel lsngitudinally back and forth along a threaded horizontal ball-screw shaft 109 journaled at its opposite ends in bearings 110 (FIGS. 2 and 5) mounted on the machine frame.
When the compression fingers are extended, each one projects up through a respective longitudinal slot llOA in the skid plate and above the level of the skid plate 38 and into the signature path so that they, like the sword 90, may be inserted behind the segregated loose bundle 13 of signatures. When retracted, the upper ends of the push rods lie below the skid plate 38. A reversible compression motor 111 (FIG. 5), mounted on the machine frame, supplies power through a gear box 112 to one end of the threaded shaft 109. Thus, as the compression motor 111 turns, the carriage and compression fingers mounted on it move back or forth along the threaded shaft 109. The fingers 106 are extended or retracted by operation of the piston 107 in which they are mounted. Instead of a piston for each compression finger, à single piston (not shown) can be used to drive a mechanical linkage (not shown) connected to each of the fingers to cause them to extend or retract as the single piston is operated. The threaded shaft 109 extends ~or the length of the accumulating conveyor and the compression unit 21.
The compression fingers are in a home position on the threaded shaft 109 at the location of the gap as it is formed by the sword and are inserted into the gap almost immediately after the gap is formed~ Compression motor 111 is operated to turn the shaft to cause the carriage 108 and compression fingers 106 to move forward and push the loose bundle from the accumulating conveyor, as described in more detail below. As the compression fingers engage the rear end of the loose bundle, the 1 sword motor 95 operates to drive the extended sword in a reverse direction until it contacts the leading signature behind the gap. This causes the sword and the sword piston to pivot in a clockwise direction (as shown in FIG. 5), causing proximity switch 98 to close. This stops the sword motor 95 so that the sword bears against the signatures with enough force (set by tension spring) to prevent the signatures from falling forward after the wings 72 are retracted, then moves the sword belt 91 forward at a rate approximately equal to that of the advancing signatures behind the gap so that the sword keeps those signatures in an upright position.
Initially, the sword 90 and compression fingers 106 are in their respective "home'l positions at the upstream end of the slots 88 and llOA in the skid plate 38, and the sword and compression fingers are retracted so that their respective upper ends are under the skid plate. After the sword 90 and side belts 40 move the signatures in the accumulating conveyor 19 a short distance forward to create the distinct gap and separate the loose bundle 13, the compression finger cylinders 107 are energized to extend the compression fingers 10~ upwardly above the skid plate 38 and into the path behind the loose bundle. At this time, the belts 26 and 30 of the consolidating conveyor 18 start moving again to prevent the upright signatures from backing up in the gate formed by the deflecting plates 54 of the orienting unit~ but the wings 72 remain extended to prevent the signatures at the downstream end of the consolidating convayor from passing into engagement with the fast-moving side belts 40 or the accumulating conveyor 13. At stated above, the sword motor 95 is energized to move the sword to the rear until it contacts the fo_ward signatures behind the gap. At the same time, compression motor 111 is energized to drive the push fingers against the rear end of the loose bundle 1 13, while the side belts 40 are driven by the gear motor to move them at the increased speed. As explained above, the right and left side belts diverge in the downstream direction so that the signatures change from a bowed to a flat configuration, and because the left side belts 40 of the accumulating conveyor run faster than those on the right side before the belts are speeded up to create the gap, the signatures are substantially perpendicular to the longitudinal axis of the path when they reach the end of the accumulating conveyor.
The compression fingers and side belts 40 cooperate to move the loose bundle rapidly all the way to the end of the accumulating conveyor 18, beyond which the compression fingers 106 continue to move the bundle and, in so doing, push it fully onto the compression unit 21 (FIG. 7f).
The wings 72 remain extended to hold the signatures at the discharge end of the consolidating conveyor 18 from contacting the fast-moving side belts 40 of the accumulating conveyor 19. Once the side belts 40 and the compression fingers 106 have delivered the bundle to the compression unit 21, the right and left servo motors are driven at a speed to move the side belts 40 at their slower, normal differential speeds (e.g., 0.25 and 0.30 in./sec. for the right and left belts, respectively), which is slightly less than that of the belts 26 and 30 of the consolidating conveyor 18. Simultaneously, the wings 72 retract and allow the signatures at the discharge end of the consolidating conveyor 18 to follow the sword and move into engagement with the now slow-moving side belts 40 of the accumulating conveyor 19, where the next bundle is accumulated.
The board drop assembly 22 (FIGS. 1 and 2) places an end board 14 (FIG. 7a) in an upright position at the discharge end of the accumulating conveyor 19, so that the leading signatures in an array of the loose bundle 1 comes against that board as the signatures advance beyond the accumulating conveyor. Just before reaching that end board, the sword is retracted so that the forward end of the loose bundle of signatures engages the board, which is released from the board drop assembly 22 and pushad forward along against a pair of upright rear stack support bars 130. The board drop assembly is also designed to deposit an end board behind the trailing end of the signatures in the loose bundle that has been separated on the accumulating conveyor 19. A board drop assembly and its operation is described in detail in U.S. Pat. No.
4/641,489 and, therefore, is not described in detail here. Any suitable board drop system can be used in conjunction with the present invention.
The path 12 for the signatures continues onto the compression unit 21, which includes longitudinally extending, parallel skid bars 128 (FIG. 3) mounted on the machine ~rame ard onto which the side belts, operating at the increased ,peed, and the compression fingers 106 drive the loose bundle 13. The skid bars 128 are long rollers which revolve about axes parallel to the signature path.
The rear stack support bars 130 (FIG. 2~ project upwardly from a slide 132 into the signature path. The slide 132 moves along a slideway 134 on the machine frame and i5 connected by a chain-and-sprocket coupling 136 to an electric clutch and stack support drive motor 138 (FIG. 10). Motor 138 can be of any suitable type, such as an a.c. nonsynchronous motor.
With no signatures on tha compression unit 21, the rear stack support bars 130 are located only slightly downstream from the board drop assembly. Thus, as signatures accumulate on the accumulating conveyor, they eventually ~ill that conveyor and move against an end board previously placed in front of them by the board 1 drop assembly. The signatures thereafter dislodge that end board and move it against the rear stack support bars 130, which yield and yet continue to direct enough force against the end board to keep it and the sig~atures at the leading end of the bundle upright and compacted (FIG.
7c). The force exerted by the rear stack support bars 130 is derived from the friction of the motor 138, bearings, belt drive, and the signature stack. This ~orce not only compacts the signatures in the compression unit, but further causes a progressive compaction along the accumulating conveyor, with the signatures at the downstream end of the accumulating conveyor being more tightly compacted than the signatures at the upstream end.
The loose bundle 13 is compressed between the compression fingers at the rear end and a stop 160 (FIGS.
2 and 3) at the forward end. The stop 160 is the end of the signature path 12. The stop 160 is mounted on an air cylinder 162 which, in turn, is secured to the machine frame. The stop 160 is bifurcated so that the banding strap 15 (FIGS. 7g and 7h) may be passed through it.
When the bundle is compressed, the compression fingers bear against the end board at the trailing end of the bundle, while the end board and rear stack support bars at the leading end abut against stop 160 (FIG. 7h). At that time, a banding strap, that is in place below the bundle and with its end projected through the slot in the bifurcated stop 160, is gathered over the bundle so that the strap extends the full length of the top and the bottom of the bundle, as well as across the outwardly presented faces of the end boards. The strap is thereafter securad around the bundle with a stra~ping machine, which may be of the conventional type.
Once the banding strap is secured in place, the compression fingers withdraw slightly and retract, and the cylinder 162 is energized to extend the stop 160 a 1 short distance upstream (FIG. 7i). The cylinder 162 immediately retracts to withdraw the stop from contact with the leading end board and the strap which extends across that board. This enables the bundle to be moved out of the signature path without snagging the strap on the stop 160. The compression fingers then return to their home position to be ready for insertion into the next gap.
In an alternate, and presently preferred, arrangement, the piston 162 is omitted, and the stop 160 is rigidly mounted in the fixed position shown in FIG. 2. After the bundle is compressed and banded, the stack control motor 131 is actuated to drive the rear stack support bars 130 rearwardly (to the left as viewed in FIGS. 2 and 7a-i) a short distance to clear the forward end of the bundle from the stop 160. The fingers are then moved ~orward slightly to be clear of the forward end of the bundle, which is then free to be removed from the signature path, as described below under I~OPERATION~.
FIG. 10 shows in block diagram form various components for controlling the machine described above and will be referred to in explaining the operation of the machine.

OP~RATION
When the machine is first placed in operation, signatures move along the feed conveyor 50 (FIG. 1) in a low, substantially horizontal, shingled condition with their folds located along one side of the conveyor so that those folds extend parallel to the direction of advance.
The feed conveyor discharges signatures one after the okher onto the receiving conveyor 17 where they strike the bump plate 52 and drop onto the receiving conveyor.
The signatures accumulate in a slight pile at the upstream end of the receiving conveyor (FIG. 7a~, where the signatures are jogged along the bump plate so as to bring 1 the ends of the signatures adjacent the bump plate into registration. The height of the pile is monitored by the paddle 53A and first rotary variable differential transformer 53 (FIGS. 2 and 10), which serves as a pile height sensor and sends a control signal through a first analog-to-digital converter (ADC) 170 to a central processing unit or computer 171, which may be o~
conventional type with a touch scr~en (not shown) for control by an operator. The signal from the pile height sensor control~ the speed o~ the gear motor 36 and belts 23 of the receiving conveyor. The belts 23 of the receiving conveyor 17 pass beneath the pile of signatures and withdraw signatures one at a time from the bottom of the pile.
Each withdrawn signature slides beneath the signature above it, but before the lowermost signature is fully extracted, the belts 23 come against the immediately overlying signature and move it as well. Thus, the ~` signatures leave from beneath the pile in a shingled condition, but with the shingle being much tighter than the relatively loose shingled condition on the feed conveyor (FIG. 7a). Not only does the direction of advance change at the trans~er from the feed conveyor to the receiving conveyor, but the orientation of the signatures also changes, because, on the receiving conveyor, the signatures advance preferably with their folded edges trailing.
The first rotary variable differential transfor~er (RVDT) 53 is set so that as long as the paddle 53A is at the desired height, the gear motor 36 operates at its ncrmal speed. However, if the rate at which signatures are delivered to the receiving conveyor decraases, say, from the printing press stopping or slowing, the paddle 53A
falls, and the first RVDT slows or stops the gear motor 36 to keep the paddle 53A at the desired height.
Conversely, if the printing press speeds up, causing 1 paddle 53A to rise, the first RVDT sends a control signal which increases the spPed of the gear motor 36 to ~eep the paddle 53A at the desired height. The signal from the first RVDT is proportional to the displacement of paddle 53A from the optimum height for the stack of signatures so the spe~d of gear motor 36 changes more for making a large correction, and less for a small correction.
Thus, the receiving conveyor is automatically and quickly controlled to move signatures at a rate corresponding with the production of the printing press.
The belts 23 of the receiving conveyor move the shingled signatures to the deflecting plates 54, where the side edges of the signatures ride up onto the sloping surfaces 56 of those plates and then move into the slightly converging gate between the plates. This causes the signatures to bow forwardly and rise at their leading edges (FIG 7a). The signatures continue to riss as the belts 26 move them through the gate between the deflecting plates 54, so that, by the time they emerge from the gate, they are standing on edge, with the folded edge down and extending transverse to the direction of travel.
Moreover, the bowing and rise tend to propagate with diminishing intensity upstream, with each signature affecting the inclination and contour of the signature following it.
When the machine is first turned on, the holding plates 60 at the downstream edges of the deflecting plates 54 are urged by the air cylinders 62 into path 12 to keep the leading signaturPs from falling out of the gate between the deflecting plates. This causes the height of the inclined signatures upstream from the deflecting plates 54 to pile up and lift paddle 64, which controls the output of the second rotary variable differential transformer 66, which acts as the gate area stream sensor.
When the paddle 64 is lifted to the required height, the 1 second RVDT tgate area stream sensor) sends a signal through a second analog-to-digital converter 172, which sends a signal through one of a group 173 of discrete input/output circuit boards to solenoid valve 63 to adjust the air pressure in the air cylinders 62 to cause the plates 60 to move to a fully open position in which they are approximately parallel and aligned with the inside passes of the side belts for the consolidating conveyor 18, as shown in FIG. 3. So disposed, the plates 60 are spaced apart a distance slightly less than the width of the signatures. This maintains the signatures in an edge-standing and forwardly-bowed configuration.
On leaving the gate, and entering the space between the holding plates 60, the signatures move onto the table belts 26 of the consolidating conveyor, which travels at a speed slightly less than the belts 23 of the receiving conveyor. This causes the signatures to consolidate. In other words, the edge-standing signatures, having been formerly shingled, occupy more space than their actual folded thickness. At the consolidating conveyor, this space is reduced. In this same region, the vibrating horizontal plate 68, riding on the upper surfaces of the signatures, urges any high signatures down so that the upper edges of the signatures are generally in registration.
The growing array of bowed signatures continues into the space between the side belts 30 of the consolidating conveyor 18 (FIG. 7a) and then, without interruption, into the space between the side belts 40 of the accumulating conveyor 19.
The left side belts 30 of the consolidating conveyor 18 are driven by the left side stepper motor 35 (FIGS. 9 and 10) at a speed slightly slower than the table belts 26 o~ the çonsolidating conveyor, and which are driven by the second gear motor 37 (shown only in FIG. 10). The right side belts 30 of the consolidating conveyor are 1 driven by the right side stepper motor 3OA (FIGS. 9 and 10) at a speed slightly greater than the table belts 26.
For example, the table belts 26 of the consolidating conveyor may run at a speed of 0.50 in./sec., the left side belts at 0.46 in./sec., and the right side belts at 0.54 inO/sec., when the signatures include picker pin holes alo~g the right upright edyes of the signatures.
This compensates for the fact that the right edgss of the signatures are effectively thicker than the left, which do not have any picker pin holes, and tends to position the signatures to be more symmetrical with respect to the lon~ikudinal axis of the path when the signatures reach the transition between the consolidating and accumulating conveyors.
The ~ide belts 40 of the accumulating conveyor 19 move slower than the belts 26 and 30 of the consolidating conveyor 18 to further consolidate the signatures on the accumulating conveyor 19, so that the space between adjacent signatures is virtually eliminated.
The left side belts 40 of the accumulating conveyor 19 are driven by the left side servo motor 4~A at a speed slightly greater than the speed at which the right side belts 40 of the consolidating conveyor 19 are driven by the right side servo motor 45B. For example, in a typical installation, the left side belts 40 are driven at a - speed of about 0.30 in./sec., and the right sid~ belts 40 are driven at a speed of about 0.25 in./sec. This helps to compensate for the tendency of the right side of the signatures to expand because of the picker pin holes on that side, and make the signatures more symmetrical with respect to the longitudinal axis of the path as the signatures approach the leading end board. The spacing between the side belts 30 and the side belts 40 is less than the width of the signatures, so the signatures remain bowed throughout the length of the consolidating conveyor 1 and most o~ the accumulating conveyor (FIG. 4). The bow in the signatures, together with the action of the sword, keeps the leading signatures upright.
As the signatures pass the retracted wings or clamps 72, the forward face of the first signature through the machine engages the extended sword 90 near its home position, and causes the sword piston to pivot forward and activate the sword proximity switch 98 (FIG. 5) ss the sword will move forward with the signatures in accordance with control signals from the CPU.
As the signatures and swcrd move along the accumulating conveyor, they approach an end board 14 held in the board drop assembly 22 (FIG. 7b). As the leading signature approaches the end board, the sword is retracted and returns to the home position shown in FIG. 7c. The leading signature proceeds forward against the end board, and the following array of signatures push the end board forward onto the skid bars 128 of the compression unit 21. The upright rear stack support bars 130 bear against the upstream side of the end board and keep it from falling forward. The rear stack support bars, being coupled with the cable cylinder 138, maintain a light force on the end board and leading signatures, yet yield as the array of signatures move into the compression unit. This force ~urther compresses the signatures together along the compression unit and induces a progressive compression along the accumulating conveyor 19.
When enough signatures have passed onto the accumulating conveyor to produce a bundle of the desired size, the CPU 171 (FIG. 10) produces signals which initiate the separation of the signatures on the accumulating conveyor from the following signatures on the consolidating conveyor. This forms the gap in the array of signatures at the transition between the consolidating and accumulating conveyors (FIG. 7c), and all signatures 1 ahead of the gap are thereafter processed as bundle 13.
The signals for creating the gap may be based from a count taken automatically along the feed conveyor 50, or from sensing the position of the lead signature moving along the path 12.
The signals that start the separation of the signatures stop the consolidating conveyor motor 37 and the left and right stepper motors 35 and 35A so the table belts 26 and side belts 30 of the consolidating conveyor stop. At the same instant, signals from the CPU (FIG. 10) momentarily speed up the left and right servo motors 44A and 44B, respectively, to speed up the side belts 40 of the accumulating conveyor 19 only long enough to move the signatures on the accumulating conveyor ahead a short distance, say, a few inches or so. This loosens the signatures at the transition between the consolidating and accumulating conveyors.
The sword air cylinder 92 is energized by a signal from the CPU to elevate the sword 90 into the loosely spaced signatures at the upstream end of the accumulating conveyor (FIG. 7d). The extended wings 72 also pr vent the side edges of those signatures not gathered by the sword 90 from coming against the side belts 40 of the accumulating conveyor. once the sword and the wings are extended, the sword motor is energized to drive the sword forward.
Ak the same time, a signal from the CPU energizes the air cylinder 76 ~or the wings 72 to move the wings to their extended position into the signature path and engage the sides of some signatures at the upstream end of the accumulating conveyor 18 (FIG. 4), and which are just upstream of the extended sword. When the wings 72 extend, the belts 26 and 30 of the consolidating conveyor again start in motion so that the signatures do not back up in the gate between deflecting plates 54.

1 At the same time, the stepper motors which drive the side belts 40 of the accumulating conveyor are activated, causing those belts to move forward again. The signatures which are upstream of the sword, and clamped by the wings (as shown in FIG. 4), are pulled free of the wings as th~
sword moves forward to create a distinct gap in the array of signatures (FIG. 7e). The cylinders 107 are actuated to extend compression fingers 106 upwardly into the gap cleared by the sword. This places the compression fingars 106 behind the bundle.
With the compression fingers extended, as shown in FIG. 7e, the side belts 40 of the accumulating conveyor 19 move at their higher speed, and the compression fingers also move forward at the ~ame speed by operation of the reversible compression motor 111 (FIG. 5). Thus, the compression fingers 106 and the side belts 40 move together and force the separated bundle out of the accumul~ating conveyor 19 and onto the roller-type skid bars 128 of the compression unit 21 tFIG. 7f). Once the trailing signature of the bundle clears the end of the accumulating conveyor 19, the compression fingers 106 continue to advance the bundle under the force exerted by them until the bundle is beyond the location at which the board drop assembly deposits an end board into the path 12.
As the bundle moves onto the skid bars 128 of the compression unit, the rear stacX support bars 130 yield, yet remain against the end hoard at the leading end of the bundle to prevent both the board and the leading signatures from falling forward. While the bundle advances, the wings 72 remain extended to prevent signatures at the discharge end of the consolidating conveyor from being caught by the fast-moviny side belts 40 of the accumulating conveyor 19. The sword motor is energized to move the extended sword rearwardly to engage any signatures that may bow excessively from the discharge end of the 1 consolidating conveyor. The sword stops when it engages those signatures and ensures that they do not fall ~orward.
After the bundle 13 is moved fully into the compression unit, servo motors 44A and 44B, which drive the left and right side belts 40 of the accumulating conveyor 19 revert back to their normal accumulating speeds, each of which is slightly less than the speed of the belts 26 and 30 for the consolidating conveyor. The air cylinders 76 retract the wings 72, thereby releasing the signatures at the discharge end of the conveyor so that their side edges can move into engagement with the side belts 40 of the accumulating conveyor. The sword remains extended, and the sword motor is energized by the proximity switch to cause the sword to move forward at approximately the same speed as the signatures. The tension spring on the sword provides adequate back pressure on the forward end of the signatures behind the sword to keep those signatures in an upright condition.
As the compression fingers move forward past the point where the drop board assembly places boards in the path 12, the drop board assembly is energized to drive a trailing end board down into the signature path behind the extended compression fingers at the rear end of the bundle. Air cylinder 107 is actuated to retract the compression fingers 106, and the compression motor is energized to turn the threaded shaft los (FIG. 5) so the retracted compression ~ingers move slightly to the rear of the end board. The compression fingers are then extended back into the path 12 behind the end board at the rear end of the bundle. The compression motor is then actuated to turn the threaded shaft so the compression ~ingers move forward again, forcing the trailing end board against the rear end of the hundle and driving the bundle against stop 160, forcing the bundle into a compact unit, which is then secured in that condition by the strap 15 1 from the strapping machine (FIGS. 7h and 7i). The compression fingers are then moved slightly to the rear, retracted, and returned to their home position to be ready for insertion into the next gap to be formed. At the same time, the cylinder 162 moves the stop to the rear and then forward. This pushes the bundle a slight distance away from the stop 160 and positions the bundle fox removal to the supporting rollers 170. Thereafter, the pusher unit 164 is energized~ and it moves the roller 166 laterally across the signature path so the roller 166 bears against the side of the bundle and drives it laterally, causing it to slide across the roller-type slide bars 128, which revolve to accommodate the movement~
The bundle then moves onto the supp~rting rollers 170.
As the compression fingers compress the bundle and hold it during the strapping operation, more signatures accumulate on the accumulating conveyor 19 so that enough signatures accumulate to form another bundle, at which time another separation is effected at the transition between the consolidating and accumulating conveyors.
The foregoing cycle is then repeated, producing another tight bundle of signatures.
With the apparatus of this invention, the consolidating conveyor side belts on the side of the signatures which ara effectiv~ly thicker than the other side are driven slightly faster than the side belts on the opposite side to make the signaturesmore symmetrical with respect to the longitudinal axis of the path by the time they reach the area where a separation gap is to be formed. This facilitates clean separation of the signatures to be bundled from the trailing signatures. In a further improvement provided by this invention, the accumulating conveyor side belts on the side of the signatures which are effectively thicker run slower than the side belts on the other side of the signatures to make the leading end of the bundle more 1 symmetrical with respect to the longitudinal axis of the path and thereby minimize distortion as the leading end of the bundle contacts the leading end board and in the subsequent compression and strapping operations. Another improvement comes from having the lowermost side belts of the consolidating and accumulating conveyors located with the lower edges of those belts substantially flush with the lower edges of the signatures on those conveyors.
This control and movement of the signatures enhances to effect cleaner separation and more compact bundling.
Thus, the present invention results in simpler construction of the machine and provides better control of the signatures for the bundle-forming operation.

Claims

1. A machine for controlling a stream of edge-standing signatures which are effectively thicker along one upright edge than another, the machine comprising;
means defining a path for the stream of signatures;
means for moving the signatures along the path from an upstream to a downstream location;
a first endless side belt mounted on one side of the path so the belt has inner and outer flights substantially parallel to the path;
first means for moving the first side belt so the inner flight moves in a downstream direction;
a second endless side belt mounted on the other side of the path so the belt has inner and outer flights substantially parallel to the path;
second means for moving the second side belt so the inner flight moves in a downstream direction; and means for moving the belts at different speeds to each other to control the relative positions of opposite edges of the signatures along the path.

2. Apparatus according to claim 1 which includes means for moving the side belt adjacent the effectively thicker upright edges of the signature faster than the other side belt.

3. Apparatus according to claim 1 which includes an endless table belt mounted between the first and second endless side belts and means for moving the table belt at a speed which is less than that of one of the side belts and greater than the speed of the other side belt.

4. Apparatus according to claim 1, 2, or 3 in which each of the side belts have upper and lower edges, and the lower edge of each side belt is at substantially the same level as the lower edges of the edge-standing signatures.

5. Apparatus according to claim 1, 2, or 3 which includes means for generating an area of looseness between adjacent signatures at the downstream end of the first and second side belts.

6. Apparatus according to claim 5 which includes a sword disposed under the path at the downstream end of the first and second side belts, means for inserting the sword into the area of looseness when it is formed, and means for moving the inserted sword downstream to create a gap between signatures downstream from the sword and signatures upstream from the sword.

7. Apparatus according to claim 1, 2, or 3 which includes a third endless side belt mounted on the same side of the path as the first endless side belt and downstream from the first side belt so the third belt has inner and outer flights substantially parallel to the path, and a fourth endless side belt mounted on the same side of the path as the second endless side belt and downstream from the second side belt so that the fourth belt has inner and outer flights substantially parallel to the path downstream from the second endless belt.

8. Apparatus according to claim 7 which includes means for driving the third and fourth endless belts at different speeds relative to each other to control the relative positions of opposite edges of the signatures long the path.

9. Apparatus according to claim 7 in which the third and fourth side belts each have upper and lower edges, and the lower edges of the third and fourth side belts are at substantially the same level as the lower edges of the edge-standing signatures.

10. Apparatus according to claim 8 which includes means for mounting the third and fourth belts to diverge from each other in a downstream direction.

11. Apparatus according to claim 9 which includes a fifth endless side belt mounted above the first endless side belt and on the same side of the path as the first endless side belt so that the fifth belt has inner and outer flights substantially parallel to the path, a sixth endless side belt mounted above the second endless side belt and on the same side of the path as the second endless side belt so the sixth belt has inner and outer flights substantially parallel to the path, a seventh endless side belt mounted above the third endless side belt and on the same side of the path as the third endless side belt, an eighth endless side belt mounted above the fourth side belt and on the same side of the path as the fourth endless side belt so the eighth endless belt has inner and outer flights substantially parallel to the path, the first, fifth, and seventh endless side belts being mounted to travel around a first common upright axis, and the second, sixth, and eighth endless side belts being mounted to travel around a second common upright axis.

12. Apparatus according to claim 11 which includes means for mounting the third and seventh belts to diverge from the fourth and eighth belts in a downstream direction.

13. Apparatus according to claim 11 in which the third belt is mounted to travel around a pair of longitudinally spaced upright axes downstream from the first common upright axis, and in which the fourth belt is mounted to travel around a pair of longitudinally spaced upright axes downstream from the second common upright axis, and means for driving the third and seventh belts at one speed, and means for driving the fourth and.
eight belt at a speed different from that of the third and seventh belts.

14. A method for controlling and moving a stream of edge-standing signatures along a path, the signatures being effectively thicker along one upright edge than another, which causes the signatures to shift into an asymmetrical orientation relative to the longitudinal axis of the path, the method including the steps of:
moving the signatures along the path from an upstream to a downstream location;
engaging the thicker upright edges of the signatures on one side of the path with a first endless belt;
engaging the upright edges of the signatures on the other side of the path with a second endless belt; and moving the belts at different speeds relative to each other to control the relative positions of opposite edges of the signatures along the path to reduce the tendency of the signatures to shift into an asymmetrical orientation with respect to the longitudinal axis of the path.

15. A method according to claim 14 which includes the step of moving the first belt faster than the second belt.

16. A method according to claim 14 which includes the steps of engaging the thicker upright edges of the signatures with a third endless belt downstream from the first endless belt and on the same side of the path as the first endless belt, and engaging the upright edges of the signatures with a fourth endless belt on the same side of the path as the second endless belt and downstream from the second endless belt.

17. A method according to claim 16 which includes the steps of moving the first endless belt faster than the second endless belt, and moving the third endless belt faster than the fourth endless belt to make the signatures more nearly symmetrical with respect to the longitudinal path along which the signatures move.