Patent Application
20070216082
The present invention relates to an apparatus for receiving and conveying sheet-like products, such as folded printed products.
An apparatus of the generic type in the form of a receiving and transfer wheel is known from EP-A 1 055 620 and corresponding U.S. Pat. No. 6,554,268. It comprises a plurality of grippers and a plurality of separating elements in the form of suction mechanisms, which are arranged on a common transporting wheel. Each gripper is assigned a separating element here. By means of the separating elements, a product which is located in a receiving region beneath the transporting wheel can be raised, at least in part, by suction attachments such that it can be gripped by a gripper. The product which is to be received is located in a stationary stack or in a moving imbricated formation and rests directly on a bearing means or, at least in part, on further products. The product is lifted up completely by virtue of the transporting wheel being rotated and, following approximately half a revolution of the transporting wheel, is released again from the corresponding gripper and deposited in an imbricated formation on a belt conveyor.
Suction mechanisms as separating elements have various disadvantages: in the first instance, the necessary suction-air feed and control means complicates the design and operation of the receiving and transfer wheel. Furthermore, a suction mechanism is only suitable to a limited extent, if at all, for lifting up relatively thick or stiff products or ones provided with loose inserts, e.g. newspapers, periodicals or catalogues, and for lifting up a plurality of products at the same time, in particular in order to form mini-stacks.
EP-A 1 364 900 and corresponding U.S. Pat. No. 7,150,454 discloses a receiving apparatus which manages without separating elements being provided in addition to grippers. The grippers themselves can be moved relative to the products which are to be received, such that a gripper jaw engages beneath, and raises, one or more products. Closure of the gripper then allows the product or the products to be gripped, and transported away, by the same gripper. It has been found in practice that the action of one of the gripper jaws engaging beneath a product can vastly limit the flexibility of the apparatus.
The fact that, in particular, printed products are often conveyed in an imbricated formation gives rise to the problem of it being necessary to compensate for irregularities in the product spacing. For this purpose, DE 196 01 693 discloses the practice of guiding the imbricated formation as a whole about a deflecting wheel which can be displaced relative to a supply and removal arrangement. It is not possible here to separate the products or change the position of the products within the imbricated formation.
The object of the invention is thus further to develop an apparatus of the type mentioned in the introduction such that there is greater flexibility in respect of the mechanical properties of the products which are to be received.
According to the invention, the separating elements each comprise at least one paddle element which is capable of engaging beneath, and raising, an edge of a product which rests, at least in part, on a further product or on a bearing surface. Suction mechanisms are not used; the product is raised solely by the paddle element as the product rests on a further product, e.g. in an imbricated formation or in a stack, or on a bearing surface. Engaging beneath is understood as meaning that the paddle element is pushed in between the product which is to be raised and the product located therebeneath, which is not to be raised, or the bearing surface. The separating element is independent of the gripper in the sense that either it is separated mechanically therefrom or it is mounted on the gripper but can be moved relative to the gripper jaws.
The paddle element or its free leading edge is lowered, in the first instance, downstream of the product edge which is to be raised, as seen in the movement direction, and is then moved relative to the product at increased speed. In the process, it engages beneath the trailing edge of the product which is to be raised, and thus separates the latter from the rest of the products or from the bearing means. Relative movement of the paddle element in the upward direction causes the trailing edge of the product to be raised and moved into a position in which it is gripped by a gripper. This means that a product edge is introduced into the open gripper mouth by the paddle element.
The function of the paddle element is preferably assisted by a stop which is arranged in a stationary manner in relation to the movement path of the paddle elements. The stop forms a resistance for the leading product edge. As the paddle elements move along their movement path, the trailing edge is thus pushed further along the paddle element and/or deeper into the gripper mouth.
The separating element and gripper, and also the corresponding movement paths, are independent of one another in principle. At least in the receiving region, however, a separating element is assigned in functional terms to each gripper. Or this purpose, the movement paths, at least in the receiving region, are parallel to one another and the speeds are coordinated with one another.
The paddle elements enclose or preferably bound a supporting surface which, during the receiving process, supports, at least in part, the product edge or surface which is to be received. The paddle element is moved such that, at least in the receiving region, the supporting surface projects, from the spatial region over which the grippers pass as they move, in the direction of the products which are to be received. Upstream and downstream of the receiving region, the supporting surface is preferably located within this spatial region. The paddle elements are moved relative to the grippers such that in the receiving region—as seen in side view—the supporting surface opens out into a gripper mouth and/or is located, at least in part, therein. The supporting surface is preferably curved convexly in relation to the movement direction of the separating elements. This assists the operation of engaging beneath, and raising, the products and ensures careful treatment of the products.
The above described movements can be realized in dependence on one another by suitable selection of the shape of the movement paths of the grippers, of the separating elements and, if appropriate, of the products which are to be received and by selection of the speeds. The paddle element can preferably also be moved, in particular pivoted, relative to its movement path in order to realize in a straightforward manner the above described movement toward, and engagement beneath, the product which is to be received. The separating elements and grippers can then also be conveyed along the same movement path and at the same speed.
The apparatus according to the invention is advantageously used in order to rearrange printed products which arrive in an imbricated formation. For example unwinding from a roll used for interim storage purposes often gives rise to an imbricated formation which is disadvantageous for further processing, e.g. has the folded edge trailing. This formation therefore has to be converted into a different one, e.g. with the folded edge leading. In order to achieve this, the products are conveyed to the receiving region by means of a supply arrangement, in particular in an imbricated formation, received by the grippers, e.g. along the trailing edge, and transferred to a removal arrangement, in particular a belt conveyor, in a discharging region with the formation being changed in the process, e.g. with the gripped edge in front. The lower leading product edges in an incoming imbricated formation thus become upper trailing edges in an outgoing imbricated formation. In an advantageous development of the invention, the supply arrangement and the removal arrangement form constituent parts of the apparatus according to the invention.
The products may also be supplied individually rather than in an imbricated formation.
In conjunction with the rearrangement of the products, it is advantageous if the apparatus according to the invention has means in order to compensate for irregularities or gaps in the incoming formation, in order that a regular formation which is discharged at timed intervals is established during transfer to the removal arrangement. Equally, it may be desirable specifically to introduce gaps into the outgoing formation and/or to change the product spacing in the outgoing formation.
In order to achieve this, in a further advantageous development of the invention, the movement paths of the grippers and of the separating elements, in their entirety, may thus be displaced in or counter to the conveying direction of the supply arrangement. A stop which is preferably present is likewise moved along therewith. For this purpose, the grippers and separating elements are arranged on a preferably common transporting mechanism, in particular a transporting wheel, which is mounted on a moveable carriage. In the case of too large a product spacing—for example if a product is missing—the transporting mechanism moves toward the product which is to be received and thus reduces the effective product spacing. If a product spacing is to be increased, movement takes place in the opposite direction.
The separating elements can preferably be activated independently of the grippers, which is advantageous, in particular, in conjunction with a displaceable transporting mechanism. Their activation can then preferably be adapted in order that, even in the event of the transporting mechanism being displaced, the movement for engaging beneath, and lifting up, a product can be carried out at the correct location relative to the moving product.
The above described displacement mechanism and the adjustable guide track can also advantageously be used for apparatuses according to the preamble of claim 1 which operate with conventional separating elements instead of paddle elements.
Examples of the invention are described hereinbelow and illustrated in the drawings, in which, purely schematically:
The transporting wheel 10 is coupled to grippers 12 and separating elements 14 at equidistant spacings along its circumference. The number of grippers 12 is equal to the number of separating elements 14. The separating elements 14 each comprise a carrier unit 16, which projects radially outward from the transporting wheel 10 and is coupled rigidly to the transporting wheel 10. The carrier unit 16 projects beyond the grippers 12 to a slight extent in the radial direction.
A paddle element 18 is arranged at the radially outer end of the carrier unit 16 such that it can be pivoted about a spindle 26 running parallel to the rotary spindle 11. The paddle element 18 comprises two legs 18a, 18b arranged in a V-shaped manner in relation to one another, as seen in side view. A first leg 18ais connected to the carrier unit 16 at one end such that it can be pivoted about the spindle 26. At its other end, it is connected to a second leg 18b and encloses an angle of approximately 90° with a tangent to this second leg. The second leg 18b is curved, is used to engage beneath the products 28 by way of its leading edge 18c, and serves as part of the supporting surface for the products. The paddle element 18 can be pivoted at least such that its leading edge 18c, in a first position, is located radially within the spatial region over which the grippers 12 pass and, in a second position, is located radially outside this region. The leading edge 18c can thus be moved toward the products 28.
The paddle elements 18 here can be pivoted through an angle of 360° about the spindle 26. In the side view shown, they are located in planes upstream or downstream of the gripper 12. For each gripper 12, it is preferably the case that two paddle elements 18 are located laterally in each case in relation to the gripper 12 (not visible in this view). The precise design of the separating elements 14 and of the pivoting mechanism will be described hereinbelow with reference to
Like the separating elements 14, the grippers 12 also have a base or carrier unit 20, by means of which they are mounted on the transporting wheel 10. They also comprise two gripper jaws 22, 24 which can assume different positions relative to one another and to the transporting wheel 10. The gripper jaws 22, 24 can be pivoted, for example, between an open position and a closed position. Synchronous movement of the gripper jaws 22, 24 allows the gripper 12 to be pivoted as a whole relative to the movement path U and/or about the gripper spindle relative to the carrier unit 20. The above described movements are realized by way of two guide tracks 62, 64. The two guide tracks 62, 64 interact with a respective guide roller 58, 60 (see
The movement path U is understood hereinbelow as meaning the movement path of the respective carrier units 16, 20 of the separating elements 14 and grippers 12. It is independent of the movements of the paddle elements 18 and of the gripper jaws 22, 24. The movement direction is understood as meaning the direction of movement of the grippers 12 and separating elements 14 along the movement path.
As an alternative to being arranged on a common transporting wheel 10, it is also possible to provide two different transporting wheels. In addition, grippers 12 and separating elements 14 may also be moved in some other way, e.g. by being coupled to a conveying mechanism—which is also common to both—or individually along suitably shaped guide rails. It is not imperative for the gripper movement path to run congruently in relation to the separation-element movement path; it is likewise possible to select a non-circular path. For example, the movement path in the discharging region may be U-shaped, as in the case of the apparatus according to EP-A 1 364 900. Instead of purely mechanical activation of the grippers and of the separating elements, electronic control is also possible in order to achieve the abovementioned movements along, and relative to, the movement path.
Beneath the transporting wheel 10, products 28 which are to be received are arranged on a bearing surface 34. The bearing surface 34, in the present case, is formed by a conveying belt 37 of a supply arrangement 36 in the form of a belt conveyor. The region between the transporting wheel 10 and the bearing surface 34, in which the products are received, is referred to as receiving region 66. A supporting-type conveying belt 102, of which the top strand is located in the plane of the conveying belt 37 of the belt conveyor 36, serves—in particular in the case of a displaceable transporting wheel 10—for preventing the conveying belt 37 from sagging and for producing a defined spacing between the rotary path U and the bearing surface 34.
The products 28, in the present case, are located in an imbricated formation S on the conveying belt 37, which moves the products in an in this case horizontal supply direction F. In the transfer region, the supply direction F runs parallel and/or tangentially to the movement path U. The paddle elements 18 and grippers 12 are moved, over the greatest possible distance, more or less parallel to the products 28 which are to be received, in order that the products are received reliably and carefully.
A removal arrangement 38, to which the products 28 are transferred, is located on that side of the transporting wheel 10 which is located opposite the receiving region 66. The region between the transporting wheel 10 and the removal arrangement 38 is referred to as the discharging region 68. The removal arrangement 38, in the present case, is likewise a belt conveyor, the product being deposited on the conveying belt thereof in an imbricated formation S′ and being conveyed away in a removal direction F′, which runs counter to the original supply direction F. In the present case, the folded edges of the products 28 in the outgoing imbricated formation S′ are located beneath a preceding product and at the front, as seen in the removal direction F′, whereas, in the incoming imbricated formation S, they are oriented to the rear, as seen in the supply direction F, and rest on a following product.
Located downstream of the transporting wheel 10, as seen in the supply direction F, is a stop 40 against which the leading edges 32 of the product 28 strike during the receiving process. For adaptation to different product lengths, the stop 40 can be displaced between two end positions 42, 44 by means of a drive (not illustrated here). The aim is for the trailing edge 30 of a product, as seen in the supply direction F, always to be located in a defined position in relation to the movement path U, in order that a paddle element 18 can engage beneath it.
Just upstream of the stop 40, as seen in the supply direction F, the bearing surface 34, in addition to the conveying belt 37, is formed by a supporting-type conveying belt 102. The latter is in, for example, a number of parts and is arranged laterally in relation to the conveying belt 37.
In order for the products 28 retained by the grippers 12 to be stabilized as the transporting wheel 10 rotates, a supporting conveyor 56 is located in the immediate vicinity of the transporting wheel 10. This supporting conveyor, in the present case, has a conveying belt 57 which acts as a pressure-exerting belt and, over approximately a quarter-rotation of the transporting wheel 10, runs parallel to the movement path U, is moved at the same speed as the products 28 and therefore stabilizes the latter until they are discharged to the removal arrangement 38. The products 29 are retained between the free end of the carrier units 16 and the conveying belt 57.
The functioning of the apparatus during the operation of receiving a product will be explained hereinbelow with reference to FIGS. 1-3:
The transporting wheel 10 and the supply arrangement 36 are driven in coordination with one another such that, in the receiving region 66, a respective product 28 comes into contact with a separating element 14 and/or a gripper 12. The adaptation of the rotational speed of the transporting wheel 10 and/or of the conveying speed of the supply arrangement 36 to the product spacing D in the imbricated formation S takes place using a control arrangement 104 which is not shown here (see
That gripper 12 which is assigned to the separating element 14 in functional terms in the receiving region 66 is located downstream of the separating element 14, as seen in the movement direction. However, the spacing between the carrier units 16, 20, the position of the trailing gripper jaw 24 and the length of the first leg 18a are selected such that in the side view shown here, i.e. as seen transversely to the conveying direction F and to the movement direction of the grippers 12 and separating elements 14, the second leg 18b and the trailing gripper jaw 24 are aligned with one another, at least in part, and the second leg 18b is located just upstream of the following gripper jaw 24, but downstream of the preceding gripper jaw 22, as seen in the supply direction F. The supporting surface defined by the second leg 18b is thus partially located in the gripper mouth—as seen in side view. This relative position is maintained until the gripper 12 is closed.
This situation is shown in
As soon as the product has been gripped by a gripper 12, the paddle element 18 is pivoted in the clockwise direction and the second leg 18b is moved away from the product 28, in this case by being pulled out from beneath the gripped product 28 in the direction of the rotary spindle 11 (see
Overall, the products are received in the receiving region 66, retained by the grippers 12 over approximately a half-rotation of the transporting wheel 10, and transferred to the removal arrangement 38 in the discharging region 68, with the grippers 12 being opened in the process. Since the edge 30 which is gripped by the gripper 12, i.e. the originally trailing edge of the product 28, is moved beneath an already released, preceding product in the discharging region 68, this results in an imbricated formation S′ in which the leading and trailing edges 30, 32 and the top/bottom positions are reversed in relation to the original formation S.
As seen in profile, the paddle element 18 comprises a first, rectilinear leg 18a and a second leg 18b in the form of a circle arc. As seen in the movement direction, the paddle element 18 may have a continuous or else interrupted surface with the profile which is shown in
The products 28 are fed in a double imbricated formation S″ in which they rest one upon the other in pairs in each case. In the present case, two products 28 of one pair are shown in a slightly offset state in order to illustrate that errors in the formation fed can also be corrected within certain limits.
For receiving products 28 in pairs, the separating elements 14 are moved such that the leading edge 18c of the paddle elements 18 engages in each case beneath the bottom, second product 28 of a pair of products and raises this product, together with the product 28 resting thereon, from the imbricated formation S″. It is possible here to compensate for irregularities.
As an alternative, it is also possible for the pairing to be formed initially in the receiving region 66, by interaction with the stop 40. In this case, the transporting wheel 10 is moved approximately at half the supply speed, so that in each case two individually conveyed-up products 28 come into contact with a gripper 12.
First of all the drive system used in the basic version of the invention will be described hereinbelow. This system comprises a first drive 74, e.g. a motor, for the transporting wheel 10. The motive power is transmitted to the transporting wheel 10 by means of a first toothed belt 72 and a gearwheel 70, which is connected concentrically, and thus rigidly, in relation to the transporting wheel 10. The toothed belt 72 here runs over a plurality of deflecting rollers 73, 73′. The toothed belt 72 also drives the supporting conveyor 56 and the removal arrangement 38 (the latter not being illustrated). The drive 74 also activates the supply arrangement 36, and controls the same, via a mechanical or electronic connection 76. For example, a gear mechanism which ensures a defined, possibly adjustable transmission ratio is located between the drive 74 and the supply arrangement 36.
According to a preferred further development of the invention, the transporting wheel 10 can be displaced in and counter to the supply direction F. In the present case, it is arranged, for this purpose, on a carriage 78 which can be displaced along an in this case horizontally running rail 86 between two end positions defined by stops 88, 90. The following elements are mounted on the carriage 78: transporting wheel 10 with the carrier units 16, 20 for the separating elements 14 and the grippers 12, respectively; stop 40, it being possible to adjust the position of the latter relative to the carriage within the region defined by the end positions 42, 44; supporting conveyor 56; roller 39 at the start of the removal arrangement 38; deflecting rollers 73′ for the toothed belt 72; supporting-type conveying belt 102.
A further drive 80 is provided for the purpose of displacing the carriage 78. The motive power is transmitted by means of a second toothed belt 81. This toothed belt 81 is connected rigidly to the carriage 78 by a coupling element 82 and runs in the supply direction F in the region of the carriage 78. The drive 80 is capable of moving the entire carriage 78, and the components coupled thereto, very quickly and counter to the supply direction F. The speed here is preferably a multiple higher than the supply speed, so that a more or less instantaneous change in position of the carriage 78 can be assumed. Since the gearwheel 70 rolls on the toothed belt 72 when the carriage 78 is displaced, the transporting wheel is driven at increased speeds during displacement in the supply direction F and at reduced speed (or is even at a standstill) during displacement in the opposite direction.
The carriage and the components connected thereto are shown in two different positions in
A sensing arrangement 92 is capable of detecting irregularities in the incoming formation S and of indicating these irregularities to a control arrangement 104 which, in turn, controls the drives 74, 80. The sensing arrangement 92 comprises, for example, a light barrier in conjunction with a further optical sensor. The light barrier serves for identifying the leading edge 32 of a product 28 downstream of an actual gap in the product stream. The further sensor serves for identifying the trailing edges 30 of the products 28. These signals are processed and give information about the regularity of the incoming formation S and, in particular, about the spacing D between the trailing edges 30. If this spacing lies outside a predeterminable tolerance range, the control arrangement 104 causes the carriage 78 to be displaced in or counter to the supply direction F. If too large a spacing, e.g. a gap 84, is determined, the carriage 78 is displaced counter to the supply direction F in order to compensate for this. In the event of too small a spacing, or in order to create a gap, the carriage 78 is displaced in the supply direction F.
In the present case, the guide track 54 for the guide rollers 46 of the separating elements 14 can be pivoted about the rotary spindle 11 of the transporting wheel 10. A, for example, hydraulically or pneumatically operating drive arrangement 94 is provided in order to execute the pivoting movement. This drive arrangement moves a piston rod 96, which is mounted in a pivotable manner on the guide track 54 itself or on a lever arm 98 which is connected rigidly thereto. Extending the piston rod 96 by a certain amount causes the guide track 54 to be rotated through an angle a. Without the drive arrangement 94 being actuated, there is no change in the orientation of the guide track 54 in space.
A gap 84 in the incoming imbricated formation S is compensated for as follows: the optical sensing arrangement 92, which is shown in
The gap 84 causes the paddle element 18 of the next separating element 14 to be located upstream, as seen in the supply direction F, of the edge 30 of the next product 28 which is to be gripped (
The function of the pivotable guide track 54 will be explained hereinbelow: as is illustrated in
This problem is solved by the guide track 54 being pivoted through an angle α of approximately 10-20° in the movement direction of the grippers 12 and separating elements 14, i.e. in this case in the counter clockwise direction. This is because, in this case, the downward pivoting movement of the paddle elements 18 is executed in a position which is located further to the rear in the movement direction. This results in the leading edge 18c remaining above the level 100 until the product 28 is located upstream of the leading edge 18c, as seen in the supply direction F. The track displacement also gives rise to a delay in the pivoting movement of the paddle element 18 which has already engaged beneath a product. However, this does not have any effect on the transfer process to the gripper 12, since the product is already positioned far enough on the bearing surface of the paddle element 18, this bearing surface being defined by the second leg 18b, to allow it to be transferred into the gripper 12.
Once the position which is shown in
The pivoting of the guide track 54, this operation being illustrated in
In order to form a gap, the carriage 78 is displaced in the supply direction F. A gripper 12 in the receiving region 66 first clutches at thin air, which results in the gap being formed in the outgoing formation S′. The carriage 78 is then pushed back again into the starting position. There is no need for the guide track 54 to be adjusted in this case.
The displacement mechanism shown in
Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
| Number | Date | Country | Kind |
|---|---|---|---|
| 00415/06 | Mar 2006 | CH | national |
