EP0278286B1 - Device for collating folded printed sheets - Google Patents

Description

The present invention relates to a device according to the preamble of patent claim 1.

Such a device is known from DE-OS 36 20 945.7 or from GB-OS 21 77 380, which is largely identical in content. In contrast to other previously known collecting devices (for example according to CH-PS 535.696 or 650.729), which only have a single, generally linear collecting conveyor, the known device is able to collect considerably more printed sheets per unit of time, because each of the collecting conveyors on the way between makes two adjacent feeders orbits around the axis of rotation and its drivers are advanced by the distance to the next feeder during this revolution. In terms of space, the drivers therefore describe a helical path. The feeders can therefore feed the folded printed sheets in practically the same number per unit of time as they occur, for example, from an upstream printing press. The drivers can be relatively slow, i.e. can be fed without risk of damage to the printed sheets.

However, in the case of the known device, care must be taken that the feed conveyors place the printed sheets on the passing conveyors in such a way that they come to rest in front of one of the arriving pushing drivers. This is only possible if the feed conveyors and the collecting conveyors are controlled and coordinated with respect to one another in such a way that the printed sheets come to rest, albeit at a small distance, in front of the driver of the relevant collecting conveyor just arriving, i.e. that a certain distance between the arriving driver and the trailing edge of the printed sheets (viewed in the conveying direction of the collecting conveyor) is maintained.

For the first printed sheet in each case this can be irrelevant if the support point on the collecting conveyor does not move itself because this first printed sheet then "remains" on the relevant collecting conveyor after being deposited until it is "caught up" by the corresponding pushing driver and only then is advanced. However, this distance is important for each additional printed sheet that comes to rest on a previously deposited sheet, in that each of these additional printed sheets can be pushed forward from the moment of the print due to the frictional engagement with the underlying printed sheet, without this additional printed sheet rests directly on the pushing driver. The result is that the edges of the printed sheets collected by the collecting conveyors are not aligned with each other. This results in the need to align the groups of printed sheets gathered on the collecting conveyors of the known device before the next operation, for example before the stapling.

From CH-A-575 303 a drum-like device for processing printed products with axially extending, radially outwardly open compartments is known. In each partition dividing one compartment from the next, a carriage forming the bottom of the compartment in question and provided with controllable gripper sets is slidably guided in the axial direction. At feed points which are offset in the axial direction, printed products which come to rest on the floor are further introduced into each compartment passing the feed points. The carriages make one conveying and one return stroke in the course of one revolution of the processing drum, the gripper sets being closed in the course of the conveying stroke in order to convey the printed products in the axial direction to the next feed point and at the same time prevent them from falling out of the compartments as they pass through the lower orbit part prevent. During the return stroke, the gripper sets are open and the printed products are prevented from being taken along by stops arranged on the partition walls. In order to align the printed products brought together at the feed points, the carriages have controlled stop fingers that move with them and can be swung out in the course of the return stroke in order to push back, if necessary, excessively advanced printed products until they abut the corresponding stop.

It is therefore to be regarded as a purpose of the invention to provide a device of the type mentioned at the outset which guarantees that the edges of the printed sheets which are brought together in groups on the collecting conveyors are aligned with one another in relation to one another.

This purpose is achieved by the proposed device according to the invention in that it has the features which are described in the characterizing part of patent claim 1.

Due to the essentially stationary stops in the axial direction, a printed sheet is prevented and held back from a feed which is caused only by frictional engagement with the underlying printed sheet, until the pushing driver also directly hits the last printed sheet. The edges of the printed sheets are thus aligned with each other.

Features of preferred embodiments of the proposed device according to the invention are described in the dependent claims.

• Fig. 1 in einer vereinfachten schaubildlichen Darstellung eine Einrichtung zum Sammeln von Druckbogen,
• Fig. 2 wiederum schematisch eine Ansicht in Richtung der Umlaufachse eine Anzahl der Sammelförderer im Bereich einer Uebergabestelle eines der Zuförderer,
• Fig. 3 eine vereinfachte Draufsicht auf Fig. 2, und
• Fig. 4 einen vereinfachten Schnitt längs der Linie IV-IV der Fig. 2.

The invention is described in more detail below, for example, with reference to the drawing. It shows:

• 1 in a simplified diagrammatic representation, a device for collecting printed sheets,
• 2 again schematically shows a view in the direction of the axis of rotation of a number of collecting conveyors in the area of a transfer point of one of the feeding conveyors,
• Fig. 3 is a simplified plan view of Fig. 2, and
• 4 shows a simplified section along the line IV-IV of FIG. 2.

The structure of the device 10 shown in FIG. 1 largely corresponds to the structure of the device described in the aforementioned DE-OS 36 20 945.7 or GB-OS 21 77 380, to which publications are expressly referred. The device 10 has a base 11, on the two ends of which a bearing block 12, 13 is provided. In the bearing blocks 12, 13, a shaft 14 is rotatably supported, which extends beyond the bearing block 12 and carries a splined sprocket 15 there. Between the bearing blocks 12, 13 sit on the end regions of the shaft 14 with two rotatable disks 16, 17. In the circumferential region of each of the disks 16, 17, the ends of rotatable conveyors 18 are rotatably mounted at a uniform circumferential distance on a circle arranged concentrically to the shaft 14. In

Fig. 1 are visible for a better overview because of only five such collecting conveyors 18, while in reality there may be considerably more, the sheet length between adjacent collecting conveyors 18 being approximately 10-30 cm.

Means are not shown here, but are described in detail in the aforementioned DE-OS or GB-OS, which ensure that all collecting conveyors 18 (which are shown as bars in FIG. 1 for the sake of simplicity) are always independent of their current position have the same orientation.

The shaft 14 and thus the disks 16, 17 are driven by a geared motor 19 via a chain and the sprocket 15 in the direction of the arrow 21, so that each of the collecting conveyors 18 rotates in a circular path around the shaft 14.

In Fig. 1, the device includes three feed conveyors 22, 23, 24 and a removal conveyor 25. The feed conveyors 22-24 are provided with controlled grippers 26, and the removal conveyor 25 also with controlled grippers 27. The feed conveyor guides folded printed sheets 28 in a hanging position in the direction of arrow 29, in which each of its grippers 26 engages one of the printed sheets 28 on its fold. In a similar manner, the feed conveyor 23 feeds folded printed sheets 30 and the feed conveyor 24 folds printed sheets 31.

In the delivery areas of the infeed conveyors 22-24, the printed sheets 28, 30, 31 are opened by means not shown in FIG. 1, after which the grippers 26 are opened so that the printed sheets astride one of the collecting conveyors 18.

Analogously, the away conveyor 25 grips with its grippers 27 at the end of each of the collecting conveyors 18 the finished product P, each consisting of one of the interlaced printed sheets 28, 30, 31, and also conveys it hanging and in the direction of arrow 32 to a further processing station, for example to a binding machine or a stapler.

A conveying mechanism is installed in each of the collecting conveyors 18 and is provided with drivers 33 arranged at regular intervals from one another. The conveyor mechanism and its drive is described in detail in the aforementioned DE-OS and GB-OS. The drivers 33 move continuously in the direction of arrow 34, i.e. 1 from left to right.

The conveying speed of the feed conveyors 22, 23, 24 and the mutual spacing of the grippers 26 are matched to the rotational speed of the collecting conveyors 18 and their mutual circumferential spacing such that a collecting conveyor 18 is always substantially below one of the grippers 26 when it is opened. Furthermore, the feed speed of the carriers 33 and the distances between the feed conveyors 22, 23, 24 are coordinated with one another such that each carrier 33 is advanced during a revolution of the corresponding collecting conveyor 18 by a distance corresponding to the distance of the feed conveyors 22, 23, 24 from each other.

As far as the similarities with the facility described in the aforementioned DE-OS or GB-OS. In the present device 10, each of the feed conveyors 22, 23, 24 stop elements 35, 36, 37 are arranged in the transfer area, all of which are essentially of the same design. These stop elements and their effect are described below with reference to FIGS. 2-4, in which the transfer area of the feed conveyor 23 around the associated stop element 36 is shown.

The feed conveyor 23 and two of its grippers 26, each of which feeds one of the printed sheets 30 in the direction of the arrow 29, are only indicated in FIG. 2. At this point it should be noted that the sheets 28, 30 and 31 are folded with a "pre-fold", ie the one part (here the trailing part) starting from the fold the bow is longer than the other. An opening device assigned to the transfer area of the feed conveyor 23 is designated by 38. This has a number of hooks which are arranged at the same mutual spacing as the grippers 26 and which, in the direction of arrow 39, rotate at about the same speed as the grippers 26 and open to the rear, into which the longer, (trailing) part of a printed sheet with its the edge opposite the fold runs in, whereby the sheet 30 is opened to form an approximately wedge-shaped opening gap 41 (FIG. 2 on the left). The collecting conveyor 18 appearing on the far left in FIG. 2 and rotating in the direction of arrow 21, on which a printed sheet 28 already lies, penetrates into this gap. The printed sheet 30 on the second collecting conveyor 18 shown from the left is just dropped by the gripper 26.

The stop element 36 essentially consists of a flat sheet metal part 42. On the rear side of this sheet metal part 42, a beam piece 44 provided with two protruding pins 43 is fastened. One end of one of two parallel and equally long pendulum rockers 45 is hinged to each of the pins 43, the other ends of which are pivotable and axially adjustable and lockable on a respective stub shaft 46. This adjustability of the stop elements along the stub shaft 46 serves to adapt the device to different formats of the printed sheets to be gathered. The shaft ends 46 start from a cantilever 47, which in turn protrudes laterally from a carrier 48 parallel to the shaft 14 and spanning the entire device.

The lower edge 49 of the sheet metal part 42 facing the collecting conveyors 18 is curved in accordance with the circular orbit of the collecting conveyors 18. If desired, the pendulously suspended sheet metal part 42 can touch the apex of several collecting conveyors 18 with its lower edge 49. If the lower edge 49 of the sheet metal part 42 should not touch the collecting conveyor 18, an adjustable and ascertainable stop arrangement 50, indicated only in a lined manner in FIG. 2, can be provided, with which the radial minimum distance of the lower edge 49 of the sheet metal part 42 from the orbit of the Collective conveyor 18 can be set. The sheet metal part 42 remains deflectable in the direction of rotation (arrow 21) of the collecting conveyor 18.

The mode of operation will be described below with reference to FIG. 3. The six collecting conveyors 18, which appear in FIG. 2, are shown with the omission of the feed conveyor 23 and the opening device 38. In Fig. 3 the different phases are clearly visible from left to right. On the first collecting conveyor 18 there is only a printed sheet 28 which is pushed in the direction of arrow 34 by the associated driver 33. On the second collecting conveyor, at a distance d in front of the driver, a printing sheet 30 falls on the printing sheet 28 already present and advanced by the corresponding driver 33. This new printing sheet 30 is immediately frictionally attached to the printing sheet 28 in the direction of the arrow 34 advanced, initially maintaining the distance d. This can be clearly seen in Fig. 3 from the third and fourth collecting conveyor from the left. The printed sheet 30 on the fourth collecting conveyor now strikes the stop element 36 and is prevented from this by a further feed movement caused by frictional engagement, while the underlying printed sheet 28 is advanced further. When the driver 33 has finally approached the stop element to a distance corresponding to the format of the printed sheets (fifth collecting conveyor from the left in FIG. 3), the printed sheets 28 (no longer visible) and 30 are aligned and at the same time pass the end of the stop element 36.

Because in this exemplary embodiment the position of the end edge 51 of the sheet metal part 42 seen in the circumferential direction changes in the circumferential direction when the radial distance of the lower edge 49 from the orbit of the collecting conveyor 18 is changed, it can be useful to change the end region 52 (FIG. 2) of the Stop element made of an elastically flexible material, for example from a rubber sheet or consisting of a row of bristles, so that this end region 52 can be passed under elastic bending by the now congruent printed sheets 28, 30 without the printed sheets being compressed.

It can be seen from FIG. 4 that each collecting conveyor 18 has a chain 53 which is guided in a guide rail 54 (FIG. 2) and to which the drivers 33 which are arranged at regular, mutually spaced intervals and protrude upwards are fastened. A number of the links of the chain 53 preceding each of the drivers 33 are also each provided with a support element 55 in the form of a saddle roof. In this exemplary embodiment, the support surface of the collecting conveyors also moves together with the drivers.

Claims (8)

1. A device for collecting folded printed sheets (28, 30, 31) wherein the printed sheets are respectively deposited individually by several feeders (22, 23, 24) astride collecting conveyors (18) with continuously pushing dogs (33), wherein provision is made for several collecting conveyors (18) extending parallel to each other at uniform peripheral distances arranged round a rotary shaft (14) and rotating round the latter, characterized in that in the zone of the point of delivery of each of the feeders (22, 23, 24) there are arranged stop elements (35, 36, 37) deflectable in the direction of rotation of the collecting conveyors (18) so as to urge the printed sheets (28, 30, 31) respectively against the pushing dog (33).

2. A device according to patent claim 1, characterized in that the stop elements (35, 36, 37) are plane and in essence orthogonal to the rotary shaft (14) and are suspended for rocking round pins (46) parallel to the rotary shaft (14) of the collecting conveyors (18).

3. A device according to patent claim 2, characterized in that the stop elements (36, 37, 38) are suspended via two rocker arms (45) which are parallel to each other on an arm (47) fixed in position.

4. A device according to patent claim 2 or 3, characterized in that the edge (49) of each of the stop elements (35, 36, 37) facing the collecting conveyors (18) has a curvature matching the path of rotation of the collecting conveyors (18).

5. A device according to patent claim 3 or 4, characterized in that the distance of the edge (49) facing the collecting conveyors (18) of each of the stop elements (35, 36, 37) from the path of rotation of the collecting conveyors (18) may be adjusted and set.

6. A device according to one of patent claims 2 to 5, characterized in that the stop elements (35, 36, 37) are made at least partly of sheet metal.

7. A device according to one of patent claims 2 to 6, characterized in that the stop elements (35, 36, 37) may, at least in their end zone (52) as viewed in the direction of rotation of the collecting conveyors (18), be passed under with an elastic deflection and consist for example, of a rubber plate or of a row of bristles.

8. A device according to one of patent claims 1 to 7, characterized in that the collecting conveyors (18), pass the end of the stop elements (35, 36, 37) as viewed in their direction of rotation, as soon as the printed sheets concerned are aligned.

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