Abstract:
A turning device ( 10 ) for a conveyance device ( 4 ) on a transfer line includes a housing ( 15 ) closed by means of a cover ( 30 ). Recesses are formed in the housing ( 15 ), into which the guide bars ( 43 ) of a semicircular-shaped turning element ( 36 ) for the conveyance device ( 4 ) mesh with positive engagement. The design of the turning device ( 10 ) allows the conveyance device ( 4 ) to be replaced without requiring access through the side of the housing ( 15 ). Furthermore, the design of the turning device ( 10 ) is particularly compact.

Description:
BACKGROUND OF THE INVENTION 
   The invention concerns a turning device for a conveyance means on a transfer line. A known turning device of this type is a component of a transfer system that comprises, at the least, a drive head for the conveyance means, the transfer line formed out of profiled bars or the like, and the turning device. The turning device and the drive head are preferably located on the end surfaces and/or end faces of the profiled bars. The object of the turning device is to redirect the conveyance means overall from the incoming line to the outgoing line of the conveyance means by making one or multiple turns. With the known turning devices, the turning elements in the turning devices are realized as turn-around rollers, turn-around cylinders, toothed rollers or pinions. It is also essential that, in the case of the known turning devices, their housing is realized either as a basic, side-opening housing with a cover, or as a housing composed of two housing halves, so that, when a conveyance means designed, e.g., as a chain is installed or replaced, access to the housing through the side is required. 
   When complex assembly and/or transfer systems are built, the individual transfer lines are usually installed very close to each other to save space, so that the transport lines can only be accessed from the top. It therefore requires a great deal of assembly work to maintain or repair the conveyance means, which makes it necessary to dismantle and reassemble the conveyance means in the turning device and/or the housing. 
   SUMMARY OF THE INVENTION 
   In contrast, the turning device according to the invention for a conveyance means on a transfer line has the advantage that very little assembly work is required when repairing or maintaining the conveyance means, since costly dismantling and/or disassembly of the transport lines can be eliminated when transport lines are situated next to each other. This is attained by means of the invention by the fact that the turning element, including the conveyance means, is capable of being guided into the housing of the turning device from above. Access through the side of the turning device is therefore no longer required. 
   Additional advantageous further developments of the turning device according to the invention for a conveyance means on a transport line result from the dependent claims. In order to also reduce the assembly expense of the turning element, it is particularly advantageous to provide guides and/or recesses in the housing, into which the turning element is capable of being inserted with positive engagement. By using hold-down devices located on the cover, the turning element need not be mounted and/or immobilized in the housing. This function is performed simultaneously by the cover that immobilizes the turning element in the housing with positive engagement. The cover with integrated hold-down function can be realized particularly easily and cost-effectively when the cover is designed together with the hold-down devices as a one-piece component. In contrast to the turn-around rollers, turn-around cylinders, etc., known in the related art, the turning element itself can be produced particularly cost-effectively when it is composed of plastic. The conveyance means then turns around directly, i.e., in contact with the turning element. Forming the turning element out of plastic also makes it possible—in a particularly advantageous exemplary embodiment—to design the turning element substantially semicircular in shape. As a result, in contrast to the known turn-around rollers, turn-around cylinders, etc., installation space equivalent to approximately half of the diameter of a turn-around roller and/or turn-around cylinder is spared. As a result, the design of the turning device having a semicircular-shaped turning element is particularly compact. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An exemplary embodiment of the invention is presented in the drawings and will be explained in greater detail hereinbelow. 
       FIG. 1  is a perspective view of the end of a transfer system with installed and uninstalled turning device, and 
       FIG. 2  is an exploded view of a turning device, according to the invention, according to FIG.  1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The turning device  10  shown in the figures is a component of a transfer system (not shown in greater detail), by means of which work piece carriers or the like can be conveyed between work stations, for example. The transfer system—only part of which is shown—comprises profiled line elements  3  situated parallel to each other and serving as transfer line, which said profiled line elements are interconnected by means of crossbars  2 . A turning element  10  is capable of being mounted on each end face of a profiled line element  3 , i.e., on a mounting surface  11 , by means of screws  12 ,  13  with a stop plate as an intermediate layer. Positioning pins  14  under the screws  12 ,  13  serve to position the respective turning device  10  on the profiled line element  3 . The turning device  10  serves to redirect an endless conveyance means, such as a chain carrier  4 , from the transfer plane  5  into a return plane  6 . 
   The turning device  10  comprises a metallic housing  15  that is produced preferably using the die-casting method. It can be formed as one piece, but it can also be composed of two interconnected housing half-shells, for example. The housing  15  has a recess  16  located below the mounting surface  11  and at the same level as the return plane  6 , through which the chain carrier  4  is capable of being guided. The housing  15  has a cavity  17  inside. A recess  21 ,  22  serving as guide is formed on each of the two opposite side walls  18 ,  19  of the housing  15 , which said recess has the shape of a rectangular groove in a lower region  23 , and the width of which is expanded in its upper region  24 . The recesses  21 ,  22  extend to the flat top side  25  of the housing  15 . Furthermore, the front wall  26  of the housing  15  facing the profiled line element  3  comprises a recess  27  that extends from the top side  25  to just below the transfer plane  5 . 
   The top side  25  and/or the cavity  17  of the housing  15  is capable of being closed by means of a cover  30  composed preferably of plastic, which said cover comprises blind holes  32  in threaded holes  31  of the housing  15  for securing it using screws. On the side facing the profiled line element  3  and/or the recess  27 , the cover  30  comprises a recess  33  matched with the size of the chain carrier  4 . On the underside of the cover  30 , the cover has two hold-down devices  34 ,  35 , which are integrally molded on the cover  30 . The bar-shaped hold-down devices  34 ,  35  align with the recesses  21 ,  22  in the side walls  18 ,  19  of the housing  15 . 
   A turning element  36  is capable of being placed in the cavity  17  of the housing. The turning element  36 —which is produced as one piece out of a wear-resistant plastic—comprises a semicircular and/or semicylindrically-shaped main frame  37  with a contact surface  38  along which the chain carrier  4  glides in the operating state. Guide plates  39 ,  40  for the chain carrier  4  are also located on the side of the main body  37  that are also designed substantially semicircular in shape and extend past the main body  37 . The width of the main body  37 , including the two guide plates  39 ,  40 , is sized so that it matches the width between the side walls  18 , 19  in the housing  15 . Moreover, guide bars  43  are integrally molded on the outwardly-facing outer surfaces  41 ,  42  of the guide plates  39 ,  40 , the shape of which is designed to match the shape of the recesses  21 ,  22  in the side walls  18 ,  19  of the housing  15 . In the exemplary embodiment shown, the guide bars  43  have a nearly rectangular outer shape to match the lower region  23  of the recesses  21 ,  22 , and they have an arched hold-down surface  45  facing the top side  25  of the housing  15 . The shape of the hold-down surfaces  45  is matched to the shape of the undersides  46  of the two hold-down devices  34 ,  35  of the cover  30 . Finally, the two guide plates  39 ,  30  comprise guide noses  47  on the side facing the front wall  26  of the housing  15  that are matched with the recess  27  in the front wall  26  of the housing  15 . 
   In order to replace a chain carrier  4  for purposes of performing maintenance or repair of the transfer system  1 , it is not necessary to remove the housing  15  from the profiled line element  3 . It is sufficient to remove the cover  30  and then remove the turning element  36 —which is supported with positive engagement by means of the guide bars  43  in the recesses  21 ,  22  in the housing  15 —from the housing  15 . A chain carrier  4  can be reinserted by guiding one end of the chain carrier  4  around the contact surface  38  of the turning element  36  and inside the housing  15  until it reaches the recess  16 . The turning element  36  is then pressed—with its guide bars  43 —downward into the recesses  21 ,  22  of the housing  15  until the guide noses  47  of the guide plates  39 ,  40  bear against the bottom of the recess  27  in the front wall  26  of the housing  15 . The vertical position of the turning element  36  is therefore adjusted in the housing  15 . 
   The height of the turning element  36  in the housing  15  can also be adjusted, of course, by designing the shape and/or depth of the recesses  21 ,  22  accordingly. Finally, the cover  30  is screwed back in place on the top side  25  of the housing  15 , whereby the two hold-down devices  34 ,  35  bear against the hold-down surfaces  45  of the two guide bars  43 , thereby preventing the turning element  36  from moving upwardly when vertical stress is placed on the turning element  36  in the direction toward the top side  25 .