GB2139196A - Device for changing the orientation of sheet material moved along a conveyor path - Google Patents

Abstract

A device for changing the orientation of a piece of sheet material (1) moved along a conveyor path (3) comprises movable grippers (15) guided by a driven device along a closed orbital path (16), actuatable between clamped and released conditions to grasp and release the piece of sheet material (1). As each conveyed piece of sheet material (1) reaches the starting point of an intended-turning portion (18) of the orbital path, the gripper clamps the fed piece (1) and transports it to the end of the path portion (18). A rotating device acting on the grippers makes it possible, during traverse of the path portion (18), to produce an incremental rotary displacement of each gripper (15), superimposed on its orbital movement, so as to rotate the clamped piece (1) through a desired angle. At the end of the path portion (18), each gripper (15) is restored to its release position, thus releasing the piece (1) in its turned orientation (9). <IMAGE>

Description

SPECIFICATION Device for changing the orientation of sheet material moved along a conveyor path This invention relates to a device for changing the orientation of sheet material moved along a conveyor path, for example sheets of paper or signatures.

For various reasons, the need frequently arises to turn advancing sheet material with respect to a given orientation. If sheets or signatures are to be worked upon in the course of their advance, as by a trimming operation along one or both side edges upon passage through a cutting station, then the sheet or signature in question must be turned 90 if the edges perpendicular to the previously trimmed edges are to be trimmed at a subsequent cutting station. Such turning operations are customarily performed by using a branched or divided conveyor path. In that case, at the end of a first portion of the conveyor path, the material is brought against a stop which prevents further transport in the direction corresponding to the first portion of the conveyor path.From this stop, further movement of the material is then along a second or branched portion of the conveyor path, in a conveyance direction which corresponds to the desired angle of turn of the material and which is at an angle to the direction of the first portion of the conveyor path.

A particular disadvantage of this known arrangement is that trouble-free operation is not ensured, particularly with increased conveying speeds. Due to resilience of the conveyed material, irregularities such as rebound, bulging or relative shifting of components of folded signatures occur upon striking against the stop. These irregularities occurto a greater extent the higher the speed of conveyance, so that, beyond the stop, further transport along the conveyor path does not proceed with the material in sufficiently exact alignment.

An object of the invention is to provide a conveyor with means to ensure that each successive piece of sheet material, after it has been turned, is accurately oriented and aligned, even if the sheet material is conveyed at relatively high speed, and regardless of its format and weight.

According to the invention a turning station is provided with a plurality of rotating grippers at equal spacings along an endless orbital path. Each gripper is arranged to engage positively and continuously and determine the orientation of one piece of sheet material, from the point of entry into the turning station until its point of discharge, and in the course of partial-orbit motion of the gripped piece between these points, it undergoes a predetermined incremental rotation about the gripper axis.By using a gripper which is guided along the intended-turn part of the orbital path, and by controlling the gripper to maintain its grip throughout the intended-turn part of the path, the sheet of material will be positively guided from beginning to end of the turning process, thus avoiding the above-mentioned irregularities as to orientation, even with high-speed operation of the conveyor system.The angle of turn of the sheet material, i.e. the amount of the change in orientation which the material undergoes during the turning process, is a result (1) of the shape of the intendedturn section of the path over which the gripper moves with its gripped material (2) of whether the rotating device for the gripper is or is not actuated to superimpose a rotary displacement upon such orbital displacement as the gripper may undergo in its course along the intended-turn section of the path.

The angle of turn can therefore be freely selected. In the case of a curved course of the intended-turn portion of the path, as for example in the case when the gripper travels along a circular orbit path, a turning action for the material results from the orbital movement of the gripper alone, i.e. without actuation of a rotating device for the gripper. Thus when the intended-turn section of path corresponds to one quarter of the circle of orbital movement, there results a 90 angle of turn, with respect to the original, entering orientation of the material. However, without actuation of the rotating device, the material remains completely unrotated with respect to the direction of orbital movement of the gripper, i.e. along its circular path.The angle of turn with respect to the direction of movement of the gripper along its orbital path then results exclusively from actuation of the rotating device for the gripper.

Accordingly, various turning options are available.

If the orbital path of the gripper has a linear section within which the material is to be turned, then actuation of the rotating device alone is the controlling factor for a predetermined change in orientation of the material, and the angle of gripper rotation corresponds to the rotation of the material with respect to its original orientation. In case of a curved path section which is intended for the turning, as for example a section representing a circular arc, then the angle of orbital travel of the gripper which corresponds to passage over the arc determines the change in orientation with respect to the original orientation, provided that the rotating device for the gripper is not actuated.If a superimposed rotary movement of the gripper is added by actuation of the gripper-rotating device, then the angle of rotation of the gripper determines the angle through which the material is rotated, with reference to the instantaneous direction of the orbital path of the gripper, in which case this gripper rotation must be taken into account, in addition to the change in orientation which results from arcuate orbital displacement. Such additional rotation leads to an increase in the speed of transport in the curved path, which makes it possible to avoid edge-overlapping, even in the case of relatively large sheet material on a relatively small path radius.

In a preferred embodiment, the grip-control device for the gripper and the rotating device for the gripper can both be actuated by the same drive means. In this way, clamp and release functions of the gripper can be synchronized in simple fashion throughout passage from startto end of the intended-turning path. The same is true for the action of the gripperrotating device.

In one advantageous embodiment, several grippers are supported in spaced relation to each other, for orbital movement along a common circular path; their support includes a rotatable central hub rotated about an axis perpendicular to the plane of the conveyance path. With grippers travelling on a common circular path, the construction of the rotating device may be particularly simple, taking the form of a planetary-gear system.In this connection, the driven part of each gripper may include a toothed-belt pulley or gear member which (in the course of orbital displacement of the gripper) travels in an orbital plane in common with a like gear for each of the other grippers; each such toothed-belt pulley or gear member has a coupled and predetermined transmission-ratio reiationship with a toothed-belt pulley or gear member which is stationary relative to the orbital movement, such that each gripper undergoes a predetermined rotary displacement in its orbital passage through the intendedturning section of the orbital path.

In a further advantageous embodiment of the invention, it is contemplated that the gripper part which is rotated is configured for pressure contact with a flat side of sheet of material and is mounted for rotation on a spoke which is connected with the central hub, the said gripper part being axially immovable relative to the rotary axis of the gripper.

A second gripper part for co-operation with the other flat side of the material sheet brings the gripper into its clamped and released positions; this second gripper part is mounted for free rotation aboutthe rotary axis of the gripper, the mount being on a clamping support which is displaceably guided on the spoke, and the guide action being parallel to the rotary axis of the gripper. In a preferred embodiment, this guided displacement is derived from a fixed drum-shaped cam or control member which is non-rotatably mounted on the axis of orbital movement of the gripper; the control member has a cam slot or groove in its periphery, and a cam follower on each of the clamping supports tracks the groove of the fixed control cam.Thus, as a function of reaching the path section intended for the turning, each gripper (as a result of its orbital displacement about the central axis of the control cam) is automatically brought into the clamped condition and then, upon leaving the said section of the path is returned to its released condition.

Embodiments of the invention will now be described in more detail by way of example, in conjunction with the drawings, in which: Figure 1 is a diagrammatic, simplified plan of a first embodiment, omitting details, and serving merelyforfunctional explanation; Figure 2 is a detailed vertical section through the embodiment of Figure 1, taken substantially along the plane ll-ll of Figures 1 and 3; Figures is a plan of the structure of Figure 2, shown to a scale reduced from that of Figure 2; Figure 4 is a view similar to Figure 1, of a second embodirnent; Figure 5 is a view similar to Figure 1, of a third embodiment; and Figure 6 is a view similar to Figure 1 of a fourth embodiment.

Referring to Figure 1, signatures 1 consisting of one-sided folded sheets of paper, move along a linear first conveyor-path portion 3, with a conveyance direction indicated by arrow 4, to a turning station, designated generally as 5. In the course of passage through the conveyor-path portion 3, the signatures 1 are trimmed along a longitudinal side edge 7, which forms the back edge, by means of an associated circular-knife trimming station (not shown) in a so-called "front trim". The turning station 5 serves to change the orientation of signatures 1 in such manner that, during the course of their passage through the next portion 8 of the conveyor path, having a conveyance direction indicated by arrow 9, a "head and foot trim" can be performed on the respective end edges 11 and 12 which are perpendiculartothe back edge 7.

Grippers 15 are movable on a closed orbital path, which in Figure lisa circular path 16, in the displacement direction indicated by an arrow 17, and each gripper 15 co-operates with a signature 1 within the intended turning portion of the path, indicated in Figure 1 by dot-dash line 18. For this purpose, and as will be explained in detail belowwith reference to Figures 2 and 3, each gripper 15 is so actuated that a signature 1 which has been moved along the conveyor-path portion 3 into the solid-line position in Figure 1 is grasped and securely clamped at the starting end of the intended turning portion 18 of the path 16.The clamped gripper 15 carries the signature 1 along the orbital path and at the same time executes a rotary displacement about the rotary axis of the gripper, in the direction indicated by rotary arrow 19, Figure 1, the gripper axis of rotation 20 being parallel to the axis 21 of orbital movement.

Having proceeded through the intended-turning portion 18, the gripper 15 is actuated, as will be explained in further detail below, from its clamped condition to its released condition, thus releasing the signature 1 in the turned position indicated by dot-dash line in Figure 1; in this turned position, due to the rotation of the gripper about its rotary axis 20, which rotation is superimposed on the orbital movement about axis 21, the signature 1 is 90'from its original orientation to the path 3 (see the position of the corner mark "I"), so that upon further transport along the conveyor-path portion 8, edge 7, which previously extended in the longitudinal direction of the path, is now the leading edge.

Figures 2 and 3 show details of the turning station 5. A cross member or bracket 23 welded to and forming part of the machine frame 22 fixedly mounts a stationary shaft 25 which extends vertically within the turning station 5 and defines the axis 21 for orbital movement of four identical grippers 15. On the central section of the shaft 25, a sleeve 27 is rotatably supported and positioned against axial displacement with respect to shaft 25, by upper and lower bearings 28 and 29 in a flange member 31 secured to bracket 23. A toothed-belt pulley 32 is connected by a feather key 33 to the lower end of sleeve 27. A toothed-belt 35 connects pulley 32 to a tooth-belt drive pulley 36 of an angle-drive unit 37 which is mounted on cross member 23 by a bracket 38. On its driven side, the angle-drive unit 37 is coupled by tooth-belt transmission means 39 to a drive motor 40 mounted on the underside of the bracket 23. Drive motor 40 is also connected by further toothed-belt transmission means 41 to a pulse generator 44.

At the upper end of the rotatable sleeve 27, a hub 42 is secured by a feather key 43 against rotation relative to the sleeve 27. The hub 42 forms part of a gripper holder which is formed in the manner of a spoked wheel. The upper end of the stationary shaft 25 extends above the upper end of sleeve 27 and fixedly mounts a drum-shaped control member 45, the upper or top side of which is covered by a circular cover plate 46.

The wheel-shaped gripper holder has four spokes 48,49, 50 and 51 integral with hub 42 (Figure 3); spokes 48 and 51 are visible in Figure 2, and their radially outward ends integrally merge with a circumferentially closed wheel rim 53 which mounts the grippers 15 and which radially laps the orbital circle 16. The wheel rim 53 has four vertical bores 54 at equal angular spacing on circle 16, and a bearing or guide sleeve 55 for a gripper shaft 56 lines each bore and is secured to rim 53, thereby establishing the rotary axis 20 and axially fixed support of each gripper 15.The upper end of each gripper shaft 56 extends upward beyond the bearing or guide sleeve 55, and this upper end is securely attached to a circular gripper plate 58 having an upper clamping surface 59, intended for application against the lower surface of the material to be securely clamped by the gripper; the upper clamping surface 59 isin a plane in common with the top of the cover plate 46 and the top of a lateral closure plate 60 which together with cover plate 46 form a machine table.

The lower end of each gripper shaft 56 extends downward below the bearing sleeve 55 and securely mounts a toothed-belt pulley 61. All fourtoothedbelt pulleys 61 are wrapped by a single associated tooth belt 63 which, as can be seen in Figure 3, is further guided in the sector between the two adjacent toothed-belt pulleys 61 associated with the spokes 51 and 48; this further guidance is over two additional toothed-belt pulleys 64 and 65 which serve as reversing rollers and which are rotatably mounted on the underside of respective corresponding spokes 48 and 51, pulleys 64 and 65 being mounted in the same plane as the toothed-belt pulleys 61.In the region between the last-mentioned toothed-belt pulleys 64 and 65, toothed belt 63 is guided around another toothed belt pulley 66, which (see Figure 2) is fixed to flange 31 and is therefore non-rotatably seated on bracket 23; pulley 66 is also located in the plane common to the other toothedbelt pulleys 61,64 and 65.

Each gripper 15 is provided with a movable clamping holder 68 of approximately C-shape (as viewed in vertical section) and the lower arm 69 of each holder 68 is mounted for axial displacement on the outer surface of the corresponding bearing sleeve 55. A guide bolt 71 holds each clamping holder 58 against rotary movement relative to the associated spokes 48 to 51, i.e. each clamping holder is retained against rotation abouttheaxisofgripper rotation (which is the longitudinal axis of sleeve 55), and each guide bolt 71 is displaceably guided in a corresponding vertical guide bore 72 in each corresponding one of the spokes 48 to 51.

Axial displacement of each clamping holder 68 along its guide sleeve 55 is produced by a camfollower roller 73 tracking in a control or cam groove 75 formed in the periphery of the stationary control member 45, each such follower roller 73 being so mounted on its clamping holder 68 as to extend radially inward with respect to the central axis 21.

The upper end of each clamping holder 68 positions a slide guide 77 in alignment with the axis of gripper rotation 20. In this guide 77, the shaft 78 for a circular gripper plate 79 is supported for rotation and axial displacement. The gripper-plate 79 on shaft 78 faces the associated lower gripper plate 58 and is of corresponding shape and dimensions. A coil spring 81, between the lower end of slide guide 77 and the gripper plate 79, is compressionally preloaded to urge shaft 78 and its gripper plate 79 to a lower-limit position, as determined by abutment of the upper, headed end or collar 82 of shaft 78 against the upper end of the slide guide 77.

In an operating situation wherein the turning station 5 interconnects conveyor and processing devices on a supply path thereto with those on a delivery path therefrom, the motor 40 is operated in such synchronism with the feeding of a signature 1 to the starting point of the intended turning path (namely, the solid-line position of signature 1 in Figure 1), that (1) a gripper 15 is at the same starting point and (2) this gripper has been brought from its released condition to its clamped condition, firmly engaging the signature 1. It will be understood that such synchronism may be achieved by controlling motor 40 by clock pulses which have been compared with control pulses supplied by the pulse generator 44 of the turning station 5.It will also be understood that actuating control of the gripper 15, from released to clamped condition, is due to cam-follower roller 73 tracking a down ramp of cam groove 75, thus downwardly displacing clamp holder 68 on its guide sleeve 55, to such an extent that the upper gripper plate 79 squeezes the signature 1 against the lower gripper plate 58, the squeeze being resiliently loaded by the compressed coil spring 81.

With orbital movement of the gripped signature about the central axis 21, the toothed-belt pulley 61 is caused to travel on toothed belt 63 as the latter is caused to travel in its engagement with the central stationary toothed-belt pulley 66. The result is to rotate pulley 61 about its gripper axis, in the course of orbital movement of the gripper about the central axis 21, in the manner of planetary gearing; as a further result, the gripper and its gripped signature rotate about the gripper axis as they are also moved along the orbital path.

At the end of the portion of the orbital path intended for turning (which portion is indicated in Figure 1 by dash-dot line 18), the relevant gripper 15 is actuated into its released condition, by a corresponding ramp of the cam groove 75, so that the turned signature 1 can now be transported further along the conveyor-path portion 8 (Figure 1). At the same time the next gripper 15 will have been brought to the starting end of the turning portion of the path, and it will have been actuated to co-operate with the next synchronously4ed signature 1.

In this embodiment, the transmission ratio for the planetary system which produces rotation of the gripper plates 58 about the axis 20 of gripper rotation is so selected that upon full passage over the orbital path, i.e. with a full revolution of hub 42 and its spokes 48 to 51,each gripper plate 59 undergoes a complete revolution about its axis 20, and this complete revolution is in a rotary direction which corresponds to the rotary direction of orbital movement about axis 21. From the start to the end of the path portion intended for turning, which amounts to a quarter-circle of the entire orbital path, the gripper plate 59 therefore turns (about its axis 20) through an angle of rotation of 90" and this rotation is superimposed on the 90 of orbital rotation in the same direction.

It will be understood that, if desired, signatures 1 could alternatively be fed to the turning station in a crosswise orientation, with the backs of the signatures as the conveyed leading edge. They would then be transported away from the turning station 5, in a longitudinal orientation, and in the direction indicated by arrow 9, with signature backs 7 on the side facing away from the turning station.

If, as shown in Figure 4, the grippers 15 are driven in the opposite direction of rotation (about their axes 20) and therefore in the clockwise direction as indicated in Figure 4, and if they are driven with a transmission ratio of 1:1 with respect to the gripper holder, then signatures 1 which enter the turning station on path 4 with laterally positioned backs 7 facing the centre of the turning stationS, will leave the turning station 5 in transverse relation to path 8, wherein their backs 7 are leading edges. To achieve this result, it will be understood that pulleys 64-65 and their reversing action may be omitted, so that toothed belt 63 may engage the central stationary pulley 66 on the circumferential side thereof which is opposite to that involved in the use of pulleys 64-65.

Figures 5 and 6 illustrate that the section of the path in which the piece of sheet material is gripped by the grippers 15 may alternatively be a straight path which adjoins a curved (edge semi-circular) section of an oval path. In the embodiment of Figure 5, the grippers 15 undergo 90 rotation in the clockwise direction, as seen from above, in the course of their movement along the straight path.

The piece of sheet material is therefore rotated 90 by the turning station, so that, for example, the back 7 of a signature 1,which is facing inward and is oriented longitudinally on path 3' upon introduction into the turning station, becomes oriented transversely and forms the front edge upon leaving the turning station on path 8'. The piece of sheet material thus leaves the turning section in the same path direction as that on which it entered it.

In the embodiment of Figure 6, the grippers 15 undergo counterclockwise rotation. Illustratively therefore, a signature 1 can be turned by 90 in such manner that the back 7, which is laterally outward in its initial orientation on path 3', becomes re-oriented to form the leading transverse edge along path 8'.

The direction of transport remains unchanged.

Claims (8)

1. A device for changing the orientation of sheet material moved along a conveyor path, for example sheets of paper or signatures, comprising:- a) at least one gripper which can be brought into a clamped position and a released position for grasping and release respectively of the material; b) a drive device for moving the or each gripper along an orbital path which is closed on itself and one portion of which is arranged for the turning of the material.

c) a control device by which the or each gripper, as a function of the passage over the start and end of the said path portion, can be brought into the clamped position and released position respectively; and d) a rotating device which, in orderto produce a rotary movement of the or each gripper around a gripper axis of rotation perpendicular to the plane of its orbital path and which rotary movement is superimposed on the orbital movement of the gripper, can be actuated in such manner that, during the passage over the said path portion, the gripper can be rotated through an angle of rotation which corresponds to the desired angle of turn through which the material is to be turned with respect to the direction of movement of the gripper along its orbital path.

2. A device according to claim 1, wherein the control device and the rotating device can be actuated by the drive device.

3. A device according to claim 1 or claim 2, wherein a plurality of grippers are connected, for orbital movement along a common circular path, in spaced relation to each other and to a central hub which is rotatable by the drive device around an axis of rotation perpendicular to the plane of the conveyor path.

4. A device according to claim 2, wherein four grippers, spaced at an angle of 90 from each other, are provided, a quarter-circle of the orbital path being provided as the portion of the path which deflects the material by 90" in its direction of conveyance and serves to turn the material, and the rotating device being designed to produce one complete revolution of each gripper for each full revolution of the orbital path with the same direction of rotation as the orbital movement.

5. A device according to claim 3, wherein the part of each gripper which is to be rotated is connected with a separate corresponding toothed gear member and these gear members, upon the orbital movement of the grippers, rotating in a common orbital plane and rolling in common on a further toothed gear member which is stationary relative to the orbital movement.

6. A device according to claim 3, wherein that part of each gripper which is connected with the rotating device is provided for application against a flat surface of the material and is axially immovable relative to the axis of rotation of the gripper, is supported for rotation on a spoke connected with the hub, and a second gripper part, provided for co operation with the opposite surface of the material, is supported for free rotation about the axis of rotation of the gripper on a support which is displaceably guided parallel to the axis of rotation of the gripper on the spoke for transferring the gripper by means of the control device into the clamped and released positions.

7. A device according to claim 6, wherein the control device for producing the displacement movement of the support has a drum-shaped control member arranged non-rotatably coaxial to the orbital movement of the gripper and has a control groove in its periphery into which engage cam feelers arranged on the supports of the revolving grippers.

8. A device for changing the orientation of sheet material along a conveyor path, the device being constructed and arranged substantially as herein described and shown in the drawings.