Patent Publication Number: US-6213463-B1

Title: Conveying apparatus for flexible, flat articles arising in an imbricated formation

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to conveying apparatuses for flexible, flat articles arising in an imbricated formation according to the preamble to claims  1  and  10 . 
     Conveying apparatuses of this type are disclosed by Swiss Patent No. 559692 and by the corresponding U.S. Pat. No. 3,877,564. A continuously revolving driven conveying mechanism has a roller chain and endless rubber sections fitted to both ends of the link pins of this roller chain. These sections form a support for the imbricated stream to be transported. At the start and at the end of the transport section, the conveying mechanism is led around sprockets. Fastened to the chain at a distance one after another are guide carriages which are led between the sprockets in hollow rails. From each of the guide carriages, there extend, to either side, a sleeve-like gripper outrigger to whose free ends movable gripper jaws are hinged. Fixed jaws arranged on the gripper outrigger, and the movable jaws, are intended to grip the imbricated formation at the two lateral channel sections. A transport belt is intended to feed the imbricated formation, resting freely, to the conveyor, the conveying mechanism coming to bear on the free flat side of the imbricated formation in the region of the sprocket. Connected directly downstream of the transport belt is a further conveying mechanism, which is designed in the manner of a chain-roller belt, driven so as to circulate and, together with the conveying mechanism deflected around the sprocket, forms a conveying and deflection gap for the imbricated formation. In the region of the conveying gap, the relevant grippers are then closed to transport the imbricated formation further. At the end of the conveying section, the transfer to a further transport belt is designed symmetrically in relation to the equipment at the start of the conveying section. In the deflection around the sprocket at the start and at the end of the conveying section, the endless conveying mechanism itself forms the support for the imbricated formation. Said mechanism must therefore be driven in the region of the sprockets and also between the latter at the same speed as the transport belts and, in addition, the grippers must clamp the products firmly in the plane of the conveying mechanism in order to avoid damage to the articles. The known conveying apparatus needs a considerable amount of space, in particular in the region of the deflection, and places close limits on the construction of the conveyor. 
     BRIEF SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to provide a generic conveying apparatus which, with a small space requirement, permits a great deal of flexibility in the construction of the conveyor. 
     This object is achieved with a generic conveying apparatus. Deflection takes place around a drum which is separate from the circulation path of the grippers. In the region of the deflection, it is thus possible for the grippers to have a different speed from that of the imbricated formation; the conveyor having the grippers is not tied to the deflection which permits different embodiments of the conveyor. The conveying apparatus can thus be adapted in a simple way to the most diverse requirements. 
    
    
     The invention will be described in more detail using an exemplary embodiment illustrated in the drawing, in which, in purely schematic form: 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a side view of part of a conveying apparatus; and 
     FIG. 2 shows, in the view in the direction of the arrow II in FIG.  1  and partly sectioned, the same part of the conveying apparatus. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The conveying apparatus has a transport belt  10  which is driven in the feed direction Z and which is intended to feed articles  12  arranged in an imbricated formation S—in the present case printed products, such as newspapers, magazines or parts thereof—resting freely to a conveyor  14  connected downstream. Arranged above the transport belt  10  is a deflection drum  16  whose axis of rotation  18  runs in the horizontal direction and at right angles to the feed direction Z. The transport belt  10  runs tangentially up to the deflection drum  16  and wraps around the latter by approximately 90°. As viewed in the feed direction Z, the conveyor  14 , which is equipped with controllable grippers  20 , runs laterally alongside the deflection drum  16 . Said conveyor is intended to use its grippers  20  to firmly clamp the imbricated formation S deflected around the deflection drum  16  in a lateral edge section  21  and to transport it further in the conveying direction F, see in particular FIG.  2 . 
     In the example shown, the transport belt  10  is formed by seven tapes  22  arranged beside one another in the manner of a tape conveyor  23 . Five of these tapes, as viewed in the direction of the axis of rotation  18 , are located in the region of the deflection drum  16 , engage around the underside of said drum and drive it. The remaining two tapes  22  are located outside the region of the deflection drum  16  underneath the conveyor  14 . The five tapes  22  led around the deflection drum  16  form a driven conveying mechanism  24  which, together with the deflection drum  16 , bounds a deflection and conveying gap  26  for the imbricated formation S. 
     The deflection drum  16  has a circular disk-shaped plate  28  along whose periphery uniformly distributed rods  30  running parallel to the axis of rotation  18  are fastened. Said rods all project from the plate  28  on that side facing away from the conveyor  14  and form a drum-like deflection cage which is open on its side opposite the plate  28 . A drive shaft  34  which is coaxial with the axis of rotation  18  and is mounted on a machine frame  32  passes freely through the center of the plate  28 . In the interior of the deflection drum  16 , a bearing element  36  is seated on the drive shaft  34 , is connected on one side to the latter by a frictional connection and to the front of which, on the other side, the plate  28  is fastened. The bearing element  36  acts with the drive shaft  34  in the manner of a loose drive, for example via a frictional connection, in order to carry along the deflection drum  16  in the direction of rotation D of the drive shaft  34 . However, it should be mentioned that the deflection drum  16  can also be mounted such that it rotates freely. 
     On the end region of the drive shaft  34  that faces away from the deflection drum  16 , a sprocket  38  and an output drive wheel  40  are rotationally fixedly seated on said shaft. A drive chain  42 , which is driven in the direction of rotation D by a drive motor (not shown), engages around the sprocket  38 . 
     Via a drive belt  44 , the output drive wheel  40  drives a drive wheel  48  arranged on an intermediate shaft  46 . The intermediate shaft  46  runs in the feed direction Z, upstream of the deflection drum  16 , in the direction at right angles to the feed direction Z, between the runs of the tapes  22 . Arranged on said intermediate shaft is an intermediate wheel  50  which is rotationally fixedly connected to the drive wheel  48  and is connected to a further drive wheel  54  by a drive belt  52  which is crossed so as to run with a reversal of the direction of rotation. Said drive wheel  54  is rotationally fixedly seated on a drive shaft  56 , on which, at the upstream end of the transport belt  10 , the deflection wheels  58  for the tapes  22  are keyed. The five tapes  22  whose active run engages around the deflection drum  16  run upward from the deflection drum  16  in an approximately vertical direction and are led around freely rotatably mounted upper deflection wheels  60 . From the latter, the return run runs downward in the vertical direction to lower deflection wheels  62 , from where it runs back to the further drive wheels  54 . The lower deflection wheels  62  are freely rotatably mounted on an axle arranged on the machine frame  32 . Also mounted on this axle are the downstream deflection wheels  62  for the two tapes  22  arranged laterally outside the deflection drum  16 . 
     The upper deflection wheels  60  are freely rotatably mounted on an axle  64 , which is arranged on a pivoting lever  66 . The latter is pivotably mounted on the machine frame  32 , adjacent to the axle of the lower deflection wheels  62 , and can be moved in the direction of the arrow U from a deflection position, shown by continuous lines in FIG. 1, into a passage position  68 , in which, as indicated by dash-dotted lines in FIG. 1, the active run of the transport belt  10  no longer engages around the deflection drum  16 , or only to a much lower extent. As a result, the conveying apparatus can be used in the manner of a diverter, for example, for separating out rejects. 
     Between the deflection drum  16  and the sprocket  38 , a cam wheel  70  is rotationally fixedly seated on the drive shaft  34 . Engaging around said cam wheel  70  is a guide rail  72  of C-shaped cross section, which has a clothoid shape in the region of the cam wheel  70 . In the region of the cam wheel  70 , the base connecting the side legs  74  of the guide rail  72  is penetrated so that the cam wheel  70  can engage in the interior of the guide rail  72  which is open to the outside in the radial direction. 
     Arranged one behind another in the guide rail  72  are carrying elements  76 , which, on one side, are guided via guide wheels  78  in the interior of the guide rail  72  and on the other side are guided by means of further guide wheels  80  on the mutually facing ends of the side legs  74  which are bent toward each other. On the side which is opposite the guide wheels  80  and thus faces the cam wheel  70 , the carrying elements  76  have tooth-like projections and depressions which are intended to interact with identically shaped teeth on the cam wheel  70 . The carrying elements  76  are thus driven in the region of the deflection by means of the cam wheel  70 . Downstream of the cam wheel  70 , the drive takes place in a jerky manner because of the carrying elements  76  resting on one another at their ends. A gripper  20  is arranged at each nth, for example fourth, carrying element  76 . For this purpose, a support  84 , from which an outrigger  86  running at right angles to the conveying direction F projects, is seated on the axles for the guide wheels  80 . A fixed gripper tongue  88  is arranged on said outrigger on that side which faces away from the support  84  and thus from the carrying element  76 , and is free in the direction of the outside. This tongue may be provided with a frictional covering. 
     On that end of the outrigger  86  which faces away from the deflection drum  16  there is seated a gripper housing  90 , on which a corrugated, spring-like, movable gripper tongue  92  is mounted about a pivot axis  94  running in the conveying direction F. A hold-open spring  96 , which is likewise fastened to the gripper housing  90  and is designed in the manner of a leaf spring, acts on the movable gripper tongue  92  in the direction of opening of the latter, so that when it is opened, it is arranged approximately at right angles to the fixed gripper tongue  88 . The pivot axis  94 , to which the movable gripper tongue  92  is fastened at one end, is connected in the interior of the gripper housing  90  to a closing lever  98  which is mounted on the latter. Freely rotatably mounted on said lever  98 , at its free end, is a control roller  100 , which is intended to interact with a fixed closing striker  102  in order to move the movable gripper tongue  92  from the open position into the closed position. Also arranged in the gripper housing  90  is a latching element of a generally known type, in order to latch the pivot axis  94  moved into the closed position. In order to release the movable gripper tongue  92 , this latch can likewise be unlocked in a generally known way, for example by means of an opening striker. 
     The guide rail  72  defines a movement track for the grippers  20 , said track being separate from the deflection drum  16 . As viewed in the conveying direction F, the movement track runs in the direction from top to bottom toward the deflection drum  16 , then around the cam wheel  70  and the drive shaft  34  and, approximately parallel to that section of the tapes  22  which runs downstream of the deflection drum  16 , in the direction from bottom to top. The guide rail  72  is designed in such a way that the circulation path  104 , along which the gripper tongues  88  are moved, bears from the inside on the imbricated formation S, laterally alongside the deflection drum  16 , in the region of the deflection of the imbricated formation S around the deflection drum  16 . For this purpose, the edge section  21  of the imbricated formation S, as can be seen from FIG. 2, projects beyond the deflection drum  16  on the side facing the conveyor  14 . This edge section  21  is supported by the two tapes  22  running rectilinearly past the deflection drum  16 . 
     The peripheral speed of the cam wheel  70  and thus the speed of the carrying elements  76  and grippers  20  is selected such that, in a section of the guide rail  72  which runs rectilinearly, these move at least approximately at the circulation speed of the transport belt  10  and thus of the tapes  22 . In the example shown, the grippers  20  thus move, in the region of the deflection drum  16 , with a higher speed than the imbricated formation S, but on the other hand these two speeds are at least approximately identical downstream of the deflection drum  16 . The closing striker  102  begins to act at the downstream end of the deflection and conveying gap  26 . In any case, the grippers  20  are closed before the articles  12  to be gripped and held by the latter have left the deflection and conveying gap  26 . 
     The apparatus shown in the figures functions as follows. The articles  12  arising in imbricated formation S, which rest freely on the transport belt  10 , come to bear on the deflection drum  16  with their free flat side  106  which faces away from the transport belt  10 , and are deflected in the upward direction in the shortest space in the deflection and conveying gap  26 . In the region of this deflection, at specific intervals, in each case the fixed gripper tongues  88  of the grippers  20  come to bear on the imbricated formation S in the edge section  21  on the radially inner flat side. At the downstream end of the deflection and conveying gap  26 , or shortly thereafter, the gripper  20  is closed by the movable gripper tongue  92  being pivoted into the closed position, so that it grips the imbricated formation S in the lateral edge section  21  and holds it firmly for further transport. 
     The distance between successive grippers  20  is preferably selected in such a way that it is slightly smaller than the length, measured in the conveying direction, of the articles  12  to be transported, so that each article  12  in the imbricated formation S is held by at least one of the grippers  20 . In a preferred way, by selecting the distance between successive grippers  20 , it is ensured that none of the articles  12  is held by three or more grippers  20 . This makes it possible to transport the imbricated formation S around curves which are located in the surface of the imbricated formation S. 
     The cage-like design of the deflection drum  16  makes it possible for the radially inner parts of the articles  12 , the radially inner sheets in the case of newspapers or magazines, to escape in a wave shape between the rods  30  in the region of the deflection. This embodiment ensures non-damaging deflection of the articles  12 , with the smallest space requirement. A further contribution to this is made by the loose drive for the deflection drum  16 . Forces which run in the peripheral direction and which could have an influence on the articles are at least approximately avoided. It is of course possible for the deflection drum  16  also to be designed with a closed outer surface. This is particularly the case when thin articles with a relatively small mutual overlap are to be transported. 
     In principle, it is also conceivable to drive the grippers  20  in such a way that their speed is lower in a rectilinear section of the guide rail  72  downstream of the cam wheel  70  than the speed of the tapes  22  and of the deflection drum  16 . This leads to the situation in which the articles  12  held firmly by a gripper  20  are bent in a wave shape between this gripper and the downstream end of the deflection and conveying gap  26 , the peaks and valleys of the wave running at right angles to the conveying direction F. This makes it possible to transport the articles  12  without damage around curves transverse to the surface of the imbricated formation S. 
     The conveying apparatus can be designed to be exactly the same at the end of the conveying section as is shown, using FIGS. 1 and 2, at the start of the conveying section. The only difference is that the conveying direction F and the direction of rotation D are reversed, and the direction in which the transport belt  10  carries articles away is opposite to the feed direction Z. Furthermore, instead of the closing striker  102 , there is an opening striker to open the grippers  20 . 
     It is of course also conceivable to design the conveyor  14  differently. As a result, because of its independence of the deflection drum  16 , the widest possible range of options is provided. 
     In the example shown, the deflection and conveying gap runs around the deflection drum  16  through about 90°. This wrap angle may be selected to be greater or smaller. This permits simple adaptation to the physical conditions. 
     The deflection drum  16  may be freely rotatably mounted on the drive shaft  34 .