METHOD AND APPARATUS FOR TRANSPORTING SIGNATURES ALONG A PATH BETWEEN TWO CONVEYORS

Abstract: The invention comprises a method and apparatus for stacking signatures into a plurality of individual bundles. The signature are conveyed to a stacker (200) by an infeed conveyor (100). The stacker (200) places counted stackes of signatures on a turnable (300) from where the individual bundles are ejected by ejecting means (303, 304) after stacking. The infeed conveyor is operated at a selected speed. The stacker, the turnable and the ejecting means are operated at a speed which is a function of the rate of speed of signatures delivered by the infeed conveyor to the stacker.

Description: The invention relates to a method and an apparatus as indicated in the pre-characterizing parts of Claims 1 and 3. In such a known apparatus (DE-B-12 53 170) only one pair of rollers, in which one of the rollers has a convex crowned surface whereas the other of the rollers has a concave surface, is used. It is the object of the invention to improve such a prior art method and apparatus, such that the infeed signatures are compressed into a V-shaped configuration when passing the signature screen from an upstream to a downstream end of the two conveyors. Said object is solved by the features as claimed in the characterizing parts of Claims 1 and 3. By means of the particular arrangement of the plurality of rollers and plurality of endless loop members and the configuration the signatures are formed in a stable and smooth V-shaped form facilitating handling and transportation of the overlapping signatures. In an aspect of the invention, a method is provided for guiding signatures arranged in an overlapping stream to a stacking station, comprising receiving the stream at an upstream end and delivering the stream to the stacking station from the downstream end; compressing the signature stream as it passes from the upstream to the downstream end; and urging the stream into a V-shaped configuration adjacent the downstream end. In another aspect, apparatus is provided for guiding signatures stream, to a stacking apparatus, comprising first and second stream guide means for receiving the stream at an upstream end and delivering the stream to the stacking apparatus from a downstream end; the first and second guide means each including cooperating upstream and downstream compressing means for compressing the signature stream; and urging means for urging signatures passing between said downstream compressing means into a substantially V-shaped configuration. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a simplified schematic elevational view of a signature stacker in accordance with the present preferred embodiment of the invention. Fig. 2 is a fragmentary top plan view of the stacker shown in Fig. 1 illustrating the infeed section thereof in accordance with the present preferred embodiment of the invention. Fig. 3 is an elevational view of the infeed section of Fig. 2. Fig. 4 is a fragmentary top plan view illustrating a portion of the infeed section of Figs. 2 and 3. Figs. 5 and 6, both partially sectionalized, show views of the upper and lower drive rollers, respectively, of the infeed section of Figs. 2 and 3. Fig. 7 is a fragmentary schematic view in elevation of the infeed section of Fig. 2 illustrating the downstream roller assembly. Stacker 30 of the present invention shown in Fig. 1 is comprised of infeed section 100, stacking section 200, turntable section 300 and control section 400. Infeed section 100 is coupled to a press conveyor, by means not shown but which are conventional and have been omitted herein for purposes of simplicity, said coupling means aligning and coupling infeed section 100 with delivery conveyor 32 which delivers signatures 34 in an overlapping stream with folded edges 34 forward (see Fig. 2). The stream of overlapping signatures 34 which may be delivered to the stacker 30 at rates of as many as 80,000 per hour or more, is fed between upper and lower conveyor belts 36 and 38 respectively only a portion of which have been shown herein for purposes of simplicity, the downstream ends of said conveyor belts 36 and 38 being entrained about rollers 40 and 42 arranged adjacent to the inlet end of infeed section 100. Noting especially Figs. 2 to 5, which show the infeed section 100 in greater detail, said section is comprised of side plates 101, 103 which are maintained in spaced parallel fashion by spacers 102 and 104, among other components. Left-hand ends 101a, 103a of plates 101, 103 are provided with openings for securing plates 101, 103 to the stacker supporting frame by suitable fastening means. Referring to Fig. 3 inlet end of infeed section 100 has a throat portion T for receiving signatures from the adjacent conveyor, which throat portion, as well as the signature feeding portion, is defined by upper and lower belt assemblies 106 and 108. As clearly shown in Fig. 2 upper belt assembly 10b is comprised of belts 110, 112 and 114 which are entrained about upstream roller 116, downstream rollers 110, 120 and 122, and intermediate rollers 124, 126. An intermediate roller assembly, comprised of roller 124 supports the intermediate portion of belts 112 and 114. Rollers 124 and 126 are mounted upon common shaft 130. Rollers 118, 120 and 122 are mounted upon common shaft 128. Lower belt assembly 108 is comprised of roller 131 about which the upstream ends of belts 132, 134 and 136 are entrained. The downstream ends of these belts are entrained about rollers 138, 140 and 142 mounted upon common shaft 144 which is mounted at the free ends of swingably mounted about shaft 150. A pair of air cylinders 152, 152 are pivotally mounted at their upper ends 152a to a bearing supporting bracket assembly 154, 156. The free end of each reciprocating piston rod 152b is coupled to one of the swingable arm assemblies 148 by pin 158. Referring to Fig. 3, suitable ports, not shown for simplicity, provide for the ingress and egress of gas under pressure for moving piston rods 152b, 152b generally upwardly to retain the lower belt assembly 108 in the operative position shown in Fig. 3 and alternatively for moving the piston rods 152b, 152b generally downwardly to swing arm assemblies 146, 148 counterclockwise about pivot 150 as shown by arrow A1, to move the free ends of arm assemblies 146, 148 and thereby move rollers 138, 140 and 142 away from the cooperating rollers 118, 120 and 122. The swingable assemblies 146, 148 and air cylinders 152, 152 serve as a drop gate which, under certain circumstances, serve to prevent the flow of signatures to the stacking section when the drop gate assembly is open, enabling the signatures to fall harmlessly upon the floor and thereby prevent the signatures from aggravating a jam condition in the stacker 10. Upper drive roller 116, shown in Figs. 3 and 5 is a substantially hollow member and is crowned at 116a and 116b for receiving and supporting belts 110 and 114 and for maintaining these belts centered upon crown regions 116a and 116b (see Fig. 5). A centrally located crown 116c receives and positions belt 112 and maintains it centered about center line 116d. As can be seen from Fig. 3, belts 110 and 114 are substantially wider than belt 112. Fig. 6 shows lower drive roller 160 which is crowned at 160a and 160b to receive and support belts 132 and 136 and which maintain these belts centered on the aforesaid crowns. A centrally located crown 160 having a significantly greater radius of curvature receives and supports belt 134 and maintains it centered about center line 160d. Belt 134 is significantly wider than belts 132 and 136. It is further to be noted that belts 132, 136 and 112 are all substantially the same width and are significantly narrower than belts 110, 114 and 134 which are all substantially the same width and hence significantly wider than belts 112, 132 and 136. Upper belts 110 and 114 have their lower ends entrained about rollers 118 and 122 which are crowned in the same manner as roller portions 116a and 116b of upper drive roller 116. The downstream end of upper belt 112 is entrained about roller 120 which is crowned in a manner similar to the crown 116c provided at the central portion of roller 116 shown in detail in Fig. 5. Upper rollers 118 and 122 have substantially the same diameter and axial length. These rollers are significantly longer and smaller in diameter than roller 120. Conversely, lower driven rollers 138 and 142, which are of the same diameter and axial length, are significantly greater in diameter and shorter in axial length than lower driven roller 140. The unique arrangement of rollers 118 through 122 and 138 through 142 can best be appreciated from a consideration of the simplified elevational view of these rollers shown in Fig. 7. The axial length of rollers 118 and 122 are each significantly greater than the axial length of rollers 138 and 142. On the other hand, the diameters of rollers 118 and 122 are significantly smaller than the diameters of rollers 138 and 142. Roller 120 has a shorter axial length and a greater diameter than roller 140. The rollers 120, 138, 142 at the downstream end of the infeed section 100 are preferably rounded at their ends. The diameters and axial length of the aforementioned downstream driven rollers serves to urge the signatures into a substantially V-shaped contour as shown by signatures' in Fig. 7. The advantages of urging the signatures into a Veed contour and which are well known in the signature handling and stacking art, reside in the fact that signatures are much easier to handle and feed due to the fact that Veed contour stiffens the signatures to obtain these advantageous handling characteristics. The unique aspect of the present invention resides in the fact that the conventional technique for obtaining Veeing of the signatures requires the provision of split shafts for both the upper and lower driven roller assemblies and to mount rollers of substantially uniform diameter and axial length upon the Veed shaft portions. In addition, in the conventional arrangement, the rollers do not engage the signatures at the imaginary center line of the signatures. The unique arrangement of the present invention, which employs straight, parallel shafts 128 and 144 and rollers of varying diameter and axial length, provides for the Veeing of signatures as well as providing an arrangemeant in which rollers 120 and 140 and hence the belts 112 and 134 entrained therearound make rolling engagement with each signature along the center line of the Veed configuration, thus assuring better alignment and feeding of the signatures. As the signatures pass through infeed section 100, their forward folded edges pass a signature counter 164 (see Fig. 3) which may be any conventional signature counter employed to count passing signatures by developing a pulse as the nose of each signature passes the signature counter. The signature counter 164 may, for example, be a mechanical device having a gear-like member which is advanced by a fraction of a revolution each time it is engaged by the forward folded edge of a signature which rotates the gear-like member through said fraction of a revolution to provide a count pulse. Although the signature counter may utilize other techniques such as optical or photoelectric techniques to generate a pulse as the forward folded edge of each signature passes the signature counter a signature detector and counter of the acoustic type as described in copending application filed in the U.S. Patent and Trademark Office concurrently herewith and assigned to a common assignee may be used. The output pulses of the signature counter are utilized in the signature counting and stacking operations, typically in the following manner: Knowing the geometry of the stacker apparatus 30 and given the velocity of the signatures at any given time, the precise moment when the leading edge of a signature reaches the intercept position can be accurately calculated. Each of the aforesaid pulses generated by the signature counter are applied to the microprocessor-base controller 400 (Fig. 1) to determine when the signature, after moving from the position where it is counted by signature counter 164, reaches a predetermined position, such as, for example, the intercept position, which will be described in greater detail hereinbelow. The infeed section 100 further comprises a motor and gear reducer 172 for driving pulley 174 mounted upon the output shaft 172a of gear reducer 172. A double sided pulley belt 176, represented by a chain line, is entrained about timing pulleys in such a way that run 176a extends between pulley 174 and pulley 178, run 176b extends between pulleys 178 and 180; run 176c extends between pulley 180 and pulley 182; run 176d extends between pulley 182 and idler pulley 184 and run 176e extends between idler pulley 184 and pulley 174. Pulleys 180 and 182 are respectively coupled to shafts 186 and 188 for respectively rotating the upper and lower drive rollers 116 and 160. Pulley 184 may be adjustably positioned along slots 101b, 103b to adjust the tension on belt 176. Aforementioned throat region T which serves to guide signatures delivered from the press conveyor, has a substantially V-shaped throat portion, which is defined by the right-hand end of the lower run of belts 110, 112 and 114 which are diagonally aligned as shown in Fig. 3, as well as the right-hand portion of the upper run of belts 132, 134 and 136 and specifically the portion of the upper run of these belts extending between roller 160 and an intermediate roller 192 mounted for freewheeling rotation upon shaft 194 which in turn is supported by the swingable arms 146 and 148 (see Figs. 2 and 3). The signatures are ultimately firmly gripped between the upper and lower belt runs as their forward folded edges pass over the portion of the belts 132 and 134 and 136 extending around roller 192. As the signatures move to the left of the last-mentioned position, they are firmly secured between the upper and lower belt runs and are moved at the linear speed of said belts, also taking into account any possible slippage normally encountered between the belts and the signatures passing therebetween. The belts are moved at a linear speed which corresponds to the linear speed of the belts 36, 38 employed deliver the signatures to the infeed section 100 by the press conveyor 22 (Fig. 1). A tachometer generator 195 is coupled, for example, to the shaft of the press conveyor upper driving roller 20 for developing a voltage level proportional to speed generated by tachometer generator 195, said pulses representing the linear speed of the press conveyor belts and hence the signatures passing therethrough. These voltage levels are coupled through an electrical interface 197 (see Fig. 2) forming part of the stacker 30 electronics which is coupled to motor 172 to control motor 172 and its gear reducer unit which determines the rotational speed of the roller shafts 186 and 188 and hence the rotating speed of the upper and lower drive rollers 116 and 160. A tachometer 196 is coupled to shaft 186 and generates pulses as shaft 186 rotates, said pulses representing the linear speed of the belts 110, 112 and 114. The pulses from tachometer 196 are utilized by the stacker controller in the tracking of signatures, as will be more fully described hereinbelow.

Claims: A method of transporting signatures along a path between two conveyors (106,108) from an upstream location to a downstream location and forming the signatures (S) into a v-shaped configuration, CHARACTERIZED BY the steps of: feeding signatures (S) between a first plurality of endless loop members (110,112,114) on the first conveyor (106) and a second plurality of endless loop members (132,134,136) on the second conveyor (108); driving each of the first and second plurality of endless loop members (110,112,114;132,134,136) generally along the path at substantially identical speeds; orienting the first plurality of endless loop members (110,112,114) in a V-shaped configuration with a respective first plurality of rollers (118,120,122) coaxially mounted along a first axis transverse to the path and having different diameters which define a V-shape; orienting the second plurality of endless loop members (132,134,136) in a V-shaped configuration opposed to the first plurality of endless loop members (110,112,114) with a respective second plurality of rollers (138,140,142) coaxially mounted along a second axis transverse to the path, opposed to the first plurality of rollers (118,120,122) and having different diameters complementary to the respective diameters of the first plurality of rollers; transporting the signatures (S) along the path by engaging the signatures (S) with the endless loop members (110,112,114;132,134,136) and forming the signatures (S) into a V-shaped configuration with the endless loop members (110,112,114;132,134,136); and discharging the signatures (S) in a V-shaped configuration from the conveyors (106,108) at the downstream location. The method of claim 1, wherein the first plurality (110,112,114) and the second plurality (132,134,136) of endless loop members have a generally flat configuration. The method of claim 1 or 2, wherein the forming step includes compressing the signatures (S) between the conveyors (106,108) and gradually forming the signatures (S) into a V-configuration along the path from the upstream location to the downstream location. Apparatus for transporting signatures along a path between two conveyors (106,108) from an upstream location to a downstream location and forming the signatures into a V-shaped configuration, CHARACTERIZED BY a first conveyor (106) having a first plurality of rollers (118,120,122) coaxially mounted along a first axis transverse to the path, the first plurality of rollers (118,120,122) having circumferential surfaces and different diameters which define a V-shape, and a first plurality of endless loop members (110,112,114) mounted to travel along the path and pass respectively over the circumferential surfaces of the first plurality of rollers (118,120,122) for transporting the signatures (S) along the path; a second conveyor (108) having a second plurality of rollers (138,140,142) coaxially mounted along a second axis transverse to the path, the second plurality of rollers (138,140,142) having respective circumferential surfaces opposed to the respective circumferential surfaces of the first plurality of rollers (118,120,122), the second plurality of rollers (138,140,142) having diameters complementary to the first plurality of rollers (118,120,122) to also define the V-shape, and a second plurality of endless loop members (132,134,136) opposed to the first plurality of endless loop members (110,112,114) and mounted to travel along the path and pass respectively over the circumferential surfaces of the second plurality of rollers (138,140,142) for transporting the signatures (S) along the path; and driving means (172) for driving the first and second endless loop members (110,112,114;132,134,136) at substantially identical speeds. The apparatus of claim 4, wherein the first plurality (110,112,114) and the second plurality (132,134,136) of endless loop members have a generally flat configuration. The apparatus of claim 4 or 5 including first and second shafts (128,144), wherein the first plurality of rollers (118,120,122) are all mounted on the first shaft (128) and the second plurality of rollers (138,140,142) are all mounted on the second shaft (144). The apparatus of claim 4 wherein the rollers (118,120,122;138,140,142) are crowned. The apparatus of claim 4, including compressing means (152) for urging the first and second conveyors (106,108) towards each other for compressing the signatures (S) between the first and second conveyors (106,108). The apparatus of claim 4, wherein the driving means includes third and fourth rollers (116,160) about which the first and second enless loop members (110,112,114;132,134,136) are respectively entrained. The apparatus of claim 9 wherein the first and second pluralities of rollers (118,120,122;138,140,142) are mounted at the downstream location, and the third and fourth rollers (116,160) are mounted at the upstream location. The apparatus of claim 9, wherein the third roller (116) includes a plurality of drive portions (116a,116b,116c) having circumferential surface portions substantially identical in diameter to each other around which the first plurality of endless loop members (110,112,114) are entrained, and wherein the fourth roller (160) includes a plurality of drive portions (160a,160b,160c) having circumferential portions substantially identical in diameter to each other around which the second plurality of endless loop members (132,134,136) are entrained. The apparatus of claim 11 wherein the drive portions (116a,116b,116c;160a,160b,160c) of the third and fourth rollers (116,160) are crowned. The apparatus of claim 4 wherein the first and second pluralities of rollers (118,120,122;138,140,142) include opposed pairs of rollers (118,138;120,140;122,142) in which one roller of the pair has a different axial length than the other roller of the pair. The apparatus of claim 8 wherein the compressing means (152) includes an intermediate roller assembly (124,126) mounted to one (106) of the first and second conveyors (106,108) between the upstream and downstream locations. The apparatus of claim 4 wherein one (118,120,122) of the first and second pluralities of rollers (118,120,122;138,140,142) has a central roller (120) having an axial length and a maximum diameter greater than the axial length. The apparatus of claim 4 wherein the rollers of the first plurality of rollers (118,120,122) rotate with respect to each other, and the rollers of the second plurality of rollers (138,140,142) rotate with respect to each other. The apparatus of claim 4 wherein the first and second pluralities of rollers (118,120,122;138,140,142) include opposed pairs of rollers (118,138;120,140;122,142) in which one roller of the pair has a larger diameter and smaller axial length than the other roller of the pair. The apparatus of claim 17 wherein the diameter of said one roller (138) of the pair is greater than its axial length and the diameter of said other roller (118) is less than its axial length. The apparatus of claim 4 wherein the first plurality of rollers (118,120,122) includes a central roller (120) and two end rollers (118,122), the central roller (120) of the first plurality of rollers (118,120,122) having a larger diameter and smaller axial length than the two end rollers (118,122) of the first plurality of rollers, and the second plurality of rollers (138,140,142) includes a central roller (140) and two end rollers (138,142), the central roller (140) of the second plurality of rollers (138,140,142) having a smaller diameter and greater axial length than the two end rollers (138,142) of the second plurality of rollers. The apparatus of claim 4 wherein the first and second plurality of endless loop members (110,112,114;132,134,136) are respectively supported at the downstream location by the first and second pluralities of rollers (118,120,122;138,140,142) to define a V-shape at the downstream location, and the first and second plurality of endless loop members (110,112,114;132,134,136) are supported at the upstream location to define a flat shape at the upstream location so that the endless loop members (110,112,114;132,134,136) gradually form flat signatures (S) into a V-shaped configuration, while transporting the signatures (5) from the upstream location to the downstream location.

Inventors: ESPINOSA, MEDARDO, WATTS, LEONARD A.
Applicants: EDS TECHNOLOGIES, INC.
Application year: 1987
Main classification: B65H31
IPC codes: B65H33, G06K13, B65H29, B65H31, B65H43