The invention pertains to the field of post-production processing of products, particularly planar and flexible products, and in particular of print shop products, and relates to a device and a method for the inverting of a copy stream of products, in particular folded planar and flexible products.
Devices by means of which products, in particular print shop products, can be transferred from one conveyer device to another are known in the state of the art. The invention disclosed here is concerned with the gravity-assisted depositing of products onto an outgoing conveying surface, which typically is level and runs substantially in a horizontal direction. For example, one such transfer occurs if a copy stream of products is rearranged into a differently-configured copy stream. An example thereof is the exit group of a folding device, e.g. according to U.S. Pat. No. 7,458,926:an incoming copy stream of folded-together products are subsequently separated by means of acceleration in the direction of folds and conveyance. The products are guided in the process. The singled products are then deposited from above, assisted by gravity, onto an outgoing conveying surface of a conveyor belt. At this juncture, an outgoing copy stream is formed of products lying on top of one other. During the actual transfer process to the removal conveyor, the products are unguided and are at least partially in free fall. In the case of high speeds of conveyance, problems can occur in the depositing onto the outgoing conveying surface, whereby the copy stream is not reliably created. An error in the depositing can also lead to a pile-up in all of the subsequent products.
EP 0 900 757 describes a device for the deceleration and scaled output of kerfs, in which the folded products, which come singly from a folder, i.e. folding device, are guided in a direction of conveyance along a curve and are decelerated there. In the operation of the conveyor device, the products remain single. At the exit of the conveyor device, they are subsequently deposited singly onto a conveyor belt. A cascade of conveyor belts follows, which are driven with decelerated conveyor speeds, whereby finally a scaled output stream is created. An eccentric revolving cam at the exit of the conveyor device serves for improving the scaled configuration.
Longitudinal folding devices create a copy stream of products, in which the folded edges of the products are aligned in the direction of conveyance and successive products are arranged inside each other. Such copy streams often can not be further processed without first being rearranged, given that the in-folded copy stream, in which the products are arranged inside each other in the manner of an onion, makes it difficult to access single products. In the state of the art, until now, a rearranging of such a in-folded formation into a copy stream in which the products lie on top of one another (copy stream inversion) is done as an essential intermediate step which limits the separation of the products. It requires additional acceleration steps, which in turn make the whole system complex and expensive and require a large footprint.
Thus, it is the object of the present invention to further develop known depositing devices so that the described drawbacks are avoided. In particular the products should be dependably positioned on the outgoing conveying surface even at high conveyor speeds. In particular, in combination with folders, i.e. folding devices, a reconfiguration of a copy stream (copy stream inversion) should be possible.
The device according to the invention features a conveyor device, which comprises an entrance and an exit as well as guide and conveyor elements for the guided conveyance of products in a direction of conveyance. The guide and conveyor elements are arranged between entrance and exit; further along their course the products are at least partially un-guided and travel further on the basis of their inertia, yet without additional active conveyance. The guide and conveyor elements thus define a trajectory along which the products move further in an un-guided manner after leaving the exit. In the present instance the surface which the products will cover and/or the space through which the products will pass due to their un-guided movement, is located under the trajectory. The trajectory is, thus, typically a curved plane, if the direction of conveyance at the exit of the conveyor device lies in the product plane.
The direction of conveyance is chosen in such a way that at the exit of the conveyor device the products have a component of movement in the horizontal direction. This thus means that the products can traverse the horizontal distance to the removal conveyor, which itself follows the conveyor device in the direction of conveyance, un-guided and without further active conveyance. The direction of conveyance is thus substantially horizontal and runs, e.g. at a slight angle to the horizontal. The outgoing conveying surface is typically located underneath the exit of the conveyor device in the vertical direction, so the products can traverse the horizontal distance despite the influence of gravity and not prematurely impact onto the removal conveyor.
According to the invention, at least one acceleration element, which is moveable along an orbital track, is situated at the exit of the conveyor device. The orbital track, which can be closed or linear (moving up and down), is located partially above and partially below the trajectory. Thus the acceleration element intersects with the free (undisturbed) trajectory. In this way, the acceleration element can interact with the product stream, preferably periodically and, as the case may be, selectively on individual products. The acceleration element is configured such that it can impart an impulse in the vertical direction to a product after the product leaves the exit. In other words, the acceleration element imparts a force with a vertical component to the product. The force is transmitted in only a moment (as a short impact) or over a longer period of time (as an accompanying acceleration element). The contact between the product and the acceleration element can be a contact surface or a contact point. Preferentially, it is either linear or planar, in particular along a line which is oriented perpendicularly to the direction of conveyance, so that no pulling action occurs along an axis which runs parallel to the direction of conveyance. The acceleration element is, for example, realized by an eccentric cam that rotates around an axle.
The method according to the invention features the following steps:
The acceleration element has the intended purpose of adjusting the spatial orientation of the product in free flight, i.e. after leaving the exit and before the impact upon the outgoing conveying surface, such that the product arrives upon the outgoing conveying surface with, preferably, a horizontal alignment. If the conveyor device is directed horizontally or inclined downwards during the guided conveyance, the acceleration element preferably gives the product a downward stroke in the area between the product middle and the trailing edge. Because of the rigidity of the product and the air resistance, it thus turns about a horizontal axis, whereby the position correction in flight is achieved.
In order that the acceleration element should selectively interact with the product, the products are preferably pulse-fed or arranged into a pulse during the guided conveyance. The acceleration element is controllably moved with the same pulse. For this, preferably a drive of the acceleration element is coupled with the external pulse generator. For instance, a shared control device is present.
The device according to the invention is used for copy stream inversion. To this end the products are fed in an incoming copy stream and deposited again in another configuration. When products are folded in a copy stream a copy stream is formed in which the folded edges of the products are aligned in the direction of conveyance and successively following products are arranged one inside the other. This incoming formation is fed into the device. The acceleration element interacts just at or immediately after the release of, in each case, the foremost product of this formation and pushes this downwards. It is thereby pushed out of the successive product (“struck off”) and separated from this. The products which are separated from one another and temporarily singled out by this means through movement substantially perpendicular to the product plane are deposited upon the outgoing conveying surface as an outgoing copy stream which consists of products which lie on top of one another. Depending on the removal conveyor speed, the products can also be further conveyed individually. Given that the pulse is retained, a pulsed postpress processing, e.g. a transfer to a gripper, is possible, without requiring that a pulse generator be inserted between.
Depending on the configuration of the products, it can be necessary to increase the spacing of the products in the incoming formation before they are struck off. To this end the device comprises preferably at least one further acceleration element, which is arranged in the area of the entrance of the conveyor device and can accelerate the products. The further acceleration element can likewise run along an orbital track and interacts with the products in a pulsed manner. Alternatively, the increase of the copy lap can occur immediately upon entrance into the conveyor device, by means of the conveyor device imposing a conveyance speed which is higher than the conveyance speed of the preceding components.
Examples of the invention are depicted in the drawings and subsequently described. Shown are, purely schematically:
a+b the singling of products from a copy stream S;
At the exit 332 of the conveyor device 312, an acceleration element 316 is located, which is moveable along a, here circular, track U. The track U intersects the trajectory 336 of the products 10. The acceleration element 316 interacts in flight upon the area of the trailing edge 11 of the product 10 and gives it a downward impulse. In this manner the product 10 is aligned approximately horizontally while in flight, and lands in this attitude upon the outgoing conveying surface 322.
a+b show schematically the singling of products with a device according to the invention from a copy stream S which consists of products 10 that are folded inside each other. The folded edges 12 are oriented in the direction of conveyance F2. The leading edges of the products 10 are respectively located inside the preceding product. The acceleration element 316 acts upon the foremost product of the formation S on the overlapping area in the region of the trailing edge (
The conveyor 312 moves the products 10 at higher speed than the preceding production components (here the folding group, see
At the exit 332 of the conveyor 312 is situated the acceleration element 316 according to the invention, which again runs about an axis A2 which is perpendicular to the direction of conveyance F2. The surface 316a which lies furthest outward in a radial direction thus interacts with the products. During the rotation, this surface 316a describes a cylindrical orbital track U.
For this reason the subsequent products of the copy stream are influenced as little as possible by the exit-side acceleration element 316; it is eccentric and preferably has the following form: the surface 316a is convex and has the form of a section of a cylinder. It lies at a constant radius with respect to the axis A2. In the direction of rotation, a concave area with reduced radius follows. The offset of the outer surface of the acceleration element 316 thus decreases suddenly. By means of this recess it is also made more difficult for the leading edge of the subsequent product to be deflected downwards. This leading edge of the subsequent product can thus move further along the un-influenced trajectory and intrude above the product which has been pushed downwards.
The removal conveyor 320 here features a belt conveyor, on whose conveyor belt 323 the products 10 are deposited. Upon leaving the depositing device 310 the products 10 are un-guided: they leave the depositing device 310 and fly in their original direction of motion F2 along a ballistic curve, until they come to rest on the conveyor belt 323. During this fundamentally un-guided movement each product 10 is selectively given an impulse by means of the acceleration element 316, through which the product attitude is improved for the depositing. In the case that the direction of movement F2 at the exit of the acceleration device is inclined downwards compared to the horizontal conveyor belt 323, the acceleration element 316 here works upon the trailing edge 11 of the product 10, and gives it an impulse in the vertical direction. The product 10 describes a small turn about a horizontal axis in the air and is aligned approximately horizontally upon or up to its arrival on the conveyor belt 323.
The positioning on the conveyor belt 323 is made easier by guiding elements in the form of brush strips 324 arranged in the slope of the direction of conveyance F2 as well as conical rollers 325 arranged sideways on the conveyor belt 323. The conical rollers 325 lie on the conveyor belt 323 and are driven along by the conveyor belt 323. Between rollers 325 and belt 323, a narrowing conveyor slot is formed, in which the products 10 are gripped and subsequently released further in the outgoing direction of conveyance. The brush strips 324 delimit the trajectory upwards and retard the products.
As an example, on the conveyor belt 323 a copy stream is generated in which the folded edges 12 of the products lead, and respectively each lies on top of the preceding product.
In another mode of operation, the acceleration element 316 can also serve to single a copy stream after it exits the conveyor device 312. This is so used if the incoming copy stream has not previously been singled. The singling of one such formation is described with reference to
As an alternative to the cross conveyor here used, a parallel conveyor can also be used, in which case the outgoing direction of conveyance F3 substantially corresponds to the direction of conveyance F2. In this case the folded edges 12 are oriented in the outgoing direction of conveyance F3.
The input conveyor 100 is fed with products 10 to be folded as a copy stream S1 or singly (not shown here), in the direction of conveyance F1, preferably directly from the printing press or from a product storage. The conveyor device 110 of the input conveyor 100, here a conveyor belt 113 with a horizontal conveyance surface 112, takes up products 10 and conveys them further. The products 10 are accelerated, relative to the original copy stream S1 with speed v1 of conveyor belt 113, by an acceleration element 101 which is arranged at the entrance of the input conveyor 100. This leads to an enlargement of the copy lap d. The regulating device 120 features a plurality of regulating elements 122 arranged in two parallel rows, which are moved along a closed orbital track U, which partially runs in the conveyance surface 112. The regulating elements 122 project from above over the conveyance surface 112. The directions of movement of the regulating elements and/or the conveyor belt 113 are similar, wherein the speed v2 of the regulating elements 122 is somewhat greater than the speed v1 of the conveyor belt 113. Through this, the trailing edges 11 of the products 10 are secured by the regulating elements 122 and brought into alignment with the lap d of the regulating elements 122. Thus, a copy stream S2 is formed, in which the copy lap can be different when compared to the incoming formation S1. Irregularities in the incoming formation S1 can also be evened out. If single products 10 should be folded, for example only every other regulating element 122 is occupied by a product 10. This can be accomplished by, for example, adjustment of the conveyance speed of the feed or via removal of every other regulating element 122.
The pulse is detected by a sensor 127. Corresponding control signals are relayed to a control device 400. The control device 400 can act upon further processing stations by means of appropriate control signals (dashed lines), so that these can process the products in the pulse that was supplied initially.
Optionally, as the products 10 are synchronized in the regulating device 120 they are aligned by the alignment device 130. To this end serve lateral guide surfaces 132 which are oriented parallel to the direction of conveyance F1 and align the products perpendicularly to the direction of conveyance F1. If further stations 150, 160 are present, the alignment can also take place additionally or subsequent to them, e.g. at the exit of the input conveyor (alignment device 170).
The present products 10 should be folded lengthwise, i.e. centrally in the direction of conveyance F1. The preferably present station for grooving 140 serves to prepare for the folding process. It features at least one roller 142 with a defined circumferential profile and a corresponding opposing element 144. At least single sheets of the products 10 are hereby furnished with at least one kink in the area where the fold 12 is to occur. The products 10 are respectively subsequently conveyed laying down. The station for grooving 140 operates continuously on the product stream, i.e. copy stream S2.
Optionally a stapling station 150 is present, by which the products 10 can be stapled in the area of the future fold 12. The stapling station 150 operates with the pulse originally imposed.
The stations 160 for feeding further products 20 are also optional. They serve to apply further products 20 onto the products 10 before folding. The products 10, 20 are then folded together. The application can occur singly. Alternatively, the further products 20 can be applied as a copy stream to the copy stream S2 or fed from below.
The folding group 200 features a further conveyor device 202 for the throughput of the products 10, here again with a circulating driven belt 204. The standing unit 210 features two planar guide elements 212 arranged beside the belt, which lie in the plane of conveyance at the entrance of the folding group and further along the direction of conveyance arch upward, come together in a v-shape and thus create a folding funnel. Alternatively the guide elements 212 can also deviate downwards. They, thus, serve to compress laterally and bring together the halves 10a, 10b of a product 10 on both sides of the fold 12 that is to be produced. Between the two guide elements 212 are arranged a plurality of press rollers 214. These press the products 10 against the belt 204 in the area of the fold 12 that is to be created. The press rollers 214 have a specific profile for the preparation of the fold 12, e.g. as described in DE-C 28 42 226 .
The bent (folded) product 10 is conveyed further in a controlled manner in a transfer unit 220 with vertical alignment of the two product halves, i.e. standing. To this end the transfer unit 220 comprises two pairs of belts 221 running over rollers, which define a vertical plane of conveyance 222. The rollers are spring-loaded, whereby a conveyance gap with variable width is formed. In standing position, the products 10 are transferred to the press unit 230.
The press unit 230 features a first press roller pair 231 with surfaces that taper narrower downwards. It thus serves to press the product halves against one another in the area above the folded edge 12 that is to be formed. A second, cylindrically-formed, roller pair subsequent thereto presses the product halves against one another in the area of the folded edge 12 and consequently fixes it. The press roller pairs 231, 232 are spring-loaded against one another and can thus accept between them products 10 of different thicknesses. However, by means of the initial regulation no jamming occurs due to irregularities in the feed, whereby it is possible to fold in the copy stream.
Subsequent to the press operation, the folded products 10 are further conveyed through a turnover device 240 and there brought from a standing position back to a lying layer. The folded formation S3 is, thus, turned approximately 90° and laid down on its side. In the case of a folded copy stream, the products 10 in the formation S3 are folded inside each other and are thus transferred to an output group 300.
Finally the device 310 according to the invention is included, which has been described in detail already with reference to
Number | Date | Country | Kind |
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1211/09 | Aug 2009 | CH | national |