Patent Application
20080136082
This application claims the priority, under 35 U.S.C. ยง119, of German Patent Application DE 10 2006 057 681.0, filed Dec. 7, 2006; the prior application is herewith incorporated by reference in its entirety.
Field of the Invention
The invention relates to a gatherer stitcher having an endless gatherer chain to which chain roof segments are fixed and together form a chain roof for the gathering and transport of folded sheets astride the chain roof. The gatherer chain has driving elements with an adjustable position. The invention also relates to a method for adapting the endless chain to a format of a product.
Generic gatherer stitchers are known. Individual folded sheets from a stack are separated, opened and deposited on the gatherer chain by folded sheet feeders. The gatherer chain has a guide device with an upper section which is constructed in the form of a knife edge and has a ridge line that defines a transport and stitching line, as well as a substantially roof-like support on which the folded sheets are transported astride. In order to reliably grip the folded sheets deposited on the gatherer chain even at high processing speed and to achieve secure driving and transport them uniformly, the gatherer chain has driving elements, which convey the deposited folded sheets in the horizontal direction. The folded sheets conveyed by the gatherer chain and the driving devices are transported by the gatherer chain as far as a stitching station, in which folded sheets lying on one another at the fold are stitched with the aid of a wire staple. For that purpose, use is made of stitching heads disposed above the gatherer chain as well as clincher boxes disposed underneath the gatherer chain, which bend over free ends of the wire staples stuck through the folded sheets by the stitching heads. Subsequently, in the delivery region, the stitched folded sheets are conveyed further by the gatherer chain for further processing. Trimming and delivery, for example, follow.
A distinction should be drawn between gatherer stitchers having a one-piece and a two-piece gatherer chain. In the case of gatherer stitchers having two-piece gatherer chains, two roller chains are disposed in parallel. One gatherer chain half performs the function of the main gatherer chain and the other gatherer chain half performs the function of the secondary gatherer chain. The saddle-like chain roof is formed from chain roof segments, which are fitted to roller chains located on the right and left in the conveying direction. European Patent EP 0 916 514 B1, for example, discloses a two-piece gatherer chain, in which the secondary gatherer chain extends only in the region of the feeder until before the stitching station, and the main gatherer chain extends along the entire transport and stitching line beyond the stitching station. A gatherer chain configured in that way permits improved accessibility in the region of the stitching station for mounting and adjustment work, and therefore a higher stitching quality.
European Patent EP 881 180 B1, corresponding to U.S. Pat. No. 6,315,107, shows a gatherer stitcher having a one-piece gatherer chain. The chain roof includes chain roof segments which are fitted to a roller chain. The driving elements are disposed fixedly on the ridge of the gatherer chain, which means that the gatherer chain can be constructed to be particularly narrow. However, that accepts the disadvantage that supporting blades disposed above the ridge on the feeders must have an appropriate spacing.
One embodiment which combats that disadvantage is disclosed in European Patent Application EP 1 074 495 A1, corresponding to Patent Abstracts of Japan JP 2001 072280 A. In that case, the driving elements are fixed to the gatherer chain in such a way that they can move, so that they can be pivoted from a position projecting substantially laterally to a position projecting substantially upward. As a result of the position change, space needed for devices fitted peripherally, for example inkjet devices, is created and in that way the driving elements do not hinder the processing of the product. Moreover, in that case the driving elements fulfill their function and guide the product on the legs or webs of the folded sheet. Following the processing station, there are restrictions arising from the pivoted driving devices. For example, the product cannot be stitched directly afterwards or checked for completeness, for example through the use of ridge thickness measurement. Before that, the driving devices again have to be pivoted into their position substantially projecting laterally.
The productivity of a gatherer stitcher does not depend only on the operating speed but instead also on how many products can be processed by the machine in a specific time. In order to increase the number of products per unit time and therefore the productivity of the gatherer stitcher without increasing the speed of the gatherer chain, the chain pitch is adapted to the product format. This means that the spacing between the driving devices on the gatherer chain is changed. Since, in the case of relatively small products, a small spacing between the driving devices on the gatherer chain is sufficient, through the use of an appropriate reduction in the size of this spacing, more products can be deposited on the gatherer chain per unit time, which increases the productivity.
The prior art discloses various approaches to a device for changing the chain pitch. For example, driving elements can be fitted to outer chain plates of roller chains through the use of screw fixing, for example, and can be removed again simply. Alternatively, driving elements can be fitted to outer chain plates of the roller chain without tools through the use of clamp connections.
In a further variant, the driving elements can be configured as plastic pins, which are plugged into saddle segments of the gatherer chain that are provided with accommodating holes.
The problem with those approaches to a device is that the manual changing of the chain pitch is complicated and time-consuming. The necessary stoppage time for the adaptation of the machine to the product format in turn causes lower productivity.
A further problem with the use of gatherer stitchers according to the prior art exists in the region of the delivery of the stitching machine. A blade moving from below into the folded and stitched edge throws the stitched product out through the use of a vertical movement. At the same instant, however, the product is still being transported onward in the horizontal direction by the driving devices. The superimposition of vertical and horizontal movement of the product can lead to markings or ink deposits on the inside of the product as a result of the driving devices moving underneath.
It is accordingly an object of the invention to provide a gatherer stitcher with a variable chain pitch and a method for adapting an endless gatherer chain to a format of a product, which overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and in which the gatherer stitcher can be used more flexibly, permits higher productivity and at the same time ensures a higher product quality.
With the foregoing and other objects in view there is provided, in accordance with the invention, a gatherer stitcher, comprising an endless gatherer chain. The gatherer chain has fixed chain roof segments together forming a chain roof for gathering and transporting folded sheets astride the chain roof. The gatherer chain also has driving elements adjustable between an inactive position forming part of the chain roof of the gatherer chain and another, active position, projecting out of the chain roof of the gatherer chain transversely relative to a conveying direction of the gatherer chain.
As mentioned above, the gatherer chain of a gatherer stitcher according to the invention has chain roof segments and driving elements, and the position of the driving elements are adjustable. Thus, in an inactive position, the driving elements form part of the chain roof of the gatherer chain and, in an active position, they project out of the chain roof of the gatherer chain transversely with respect to the conveying direction and fulfill the function of a driving device. In this case, the gatherer chain itself can be constructed in one piece or two pieces. In an advantageous embodiment, the driving element is configured in such a way that it can be folded and can be driven by a control device. The control device includes a drive device and a control mechanism, with the drive device being stationary or displaceable and the control mechanism being moved as part of the gatherer chain. The drive device acts on the control mechanism, by which the position of each driving element can be adjusted individually, which is to say the driving element can be activated or deactivated. The control mechanism has a control lever, compression springs, pivoting levers with knife edges and knife edge bearings. In the case of a knife edge bearing, the knife edge of a body rolls in a pan-like opposing body of greater hardness and permits a swinging movement of the body.
In a particularly advantageous embodiment, the driving devices seated on the gatherer chain on the right and left in the conveying direction are driven individually. If, on one side of the gatherer chain, there is, for example, an inkjet device for printing products or a label dispenser for affixing labels, it is advantageous to fold the driving elements in completely in the processing region. The driving elements are thus inserted into the driving chain roof, form part of the supporting surface of the chain roof and in no way hinder inline processing. To this end, before the processing station there is a drive device which folds the driving element in, that is to say deactivates it and, after the processing station, a further drive device which folds the driving element out and activates it again.
In a further advantageous embodiment of the invention, a drive device is also fitted in the delivery region. The controllable driving device ensures exact positioning of the product with respect to the delivery center which depends on the format, that is to say on the spine length of the product, through the use of a variable time at which the contact of the driving element with the limb or web of the folded sheet is cancelled. The necessary drive device can be implemented, for example, through the use of a displaceable control cam acting on the control mechanism. In order to adapt the chain pitch on the gatherer chain to the product format to be processed, and therefore to increase the productivity of the gatherer stitcher, the driving elements are fitted to the gatherer chain at defined distances. The distances are dimensioned in such a way that, through the use of folding in and out, familiar formats, such as the German Standards DIN A4, DIN A3, legal, letter, tabloid or other special formats, can be implemented.
With the objects of the invention in view, there is concomitantly provided a method for adapting an endless gatherer chain of a gatherer stitcher to a format of a product to be processed. The method comprises:
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a gatherer stitcher with a variable chain pitch and a method for adapting an endless gatherer chain to a format of a product, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now to the figures of the drawings in detail and first, particularly, to
A first feeder 5, which is located at the start of a gathering section, deposits a separated folded sheet 205 on a gatherer chain or raceway 20. The feeder is a drum feeder according to the prior art. The folded sheet 205 is transported onward in a conveying direction a through the use of the gatherer chain 20, which has driving or pushing elements 24 (not designated in
Depending on the number of folded sheets which form the brochure, even further feeders, which are not illustrated in
The brochure, which is completed to this extent, is transported onward by the gatherer chain 20 in the conveying direction a as far as the stitching station 8. There, the brochure is stitched in a known manner by stitching heads that are not designated in
A trimmer and a delivery, which are not illustrated in
One half of an uppermost folded sheet 207 is raised into a virtually horizontal position during the conveying movement in the conveying direction a through the use of a device 7. In this way, an inkjet device 2 is able to print the folded sheet 207 on its inside and the folded sheet 202 located underneath it. In order to ensure that the driving element 24 (not designated in
Furthermore, the gatherer stitcher 100 has a dispensing device 9 for applying further products to the folded sheet 209. This can be a label dispenser, product sample sticker, card dispenser or the like. In order to ensure that the driving element 24 (not designated in
The inkjet device 4 and the dispensing device 9 are disposed after the cover folder feeder 3 in the conveying direction a in the exemplary embodiment of
The cross-sectional illustration in
| Number | Date | Country | Kind |
|---|---|---|---|
| DE102006057681.0 | Dec 2006 | DE | national |
