Patent Publication Number: US-7222724-B2

Title: Apparatus for transporting flat work pieces

Description:
BACKGROUND OF THE INVENTION 
   Field of the Invention 
   The invention relates to an apparatus for transporting flat work pieces in a transport direction. The apparatus has a first conveyor which makes contact with a first surface of a respective one of the work pieces, a second conveyor which makes contact with a second surface, lying opposite the first surface, of a respective one of the work pieces, and an inlet mouth which is formed by the two conveyors and has a mouth lower part and a mouth upper part. 
   An apparatus of this type is, inter alia, a constituent part of a standing sheet deliverer, which has been marketed by the applicant under the type designation SBP. The flat work pieces which are transported in a conveying direction are, for example, brochures which are received by a processing station which is situated upstream with regard to the transport direction, such as a preceding station in the form of a folding machine or a gathering and stitching machine etc., and are transferred to a further processing station which is situated downstream, such as a press station. 
   Different types of the abovementioned preceding stations also have, in particular, different outlet heights. As the brochures are to be output at an ergonomically favorable level by the apparatus which transports them, the known apparatus is disposed pivotably, in such a way that the inlet height of the apparatus can be adapted to different outlet heights of different preceding stations while substantially maintaining the outlet height of the apparatus. 
   The conveyors of the known apparatus are configured as flexible drives. Accordingly, the apparatus contains side walls and axles and shafts mounted in the latter for guide rollers and drive rollers for flexible drive devices which are configured in the form of endless round belts and form conveying runs which face one another and extend from an inlet mouth to an outlet mouth. The inlet mouth and the outlet mouth have a fixed geometry. In order to counteract the entry behavior of the flat work pieces which is impaired as a result of specific pivoting positions of the flexible drive conveyor, the length of the latter is dimensioned in such a way that, even in the case of a relatively small pivoting range, the inlet mouth can be raised and lowered within a sufficiently large range. 
   SUMMARY OF THE INVENTION 
   It is accordingly an object of the invention to provide an apparatus for transporting flat work pieces which overcomes the above-mentioned disadvantages of the prior art devices of this general type, which, even given an overall length which is shortened compared with the prior art devices mentioned in the introduction, the result is a favorable entry behavior of the flat work pieces into the apparatus. 
   With the foregoing and other objects in view there is provided, in accordance with the invention, an apparatus for transporting flat work pieces in a transport direction. The apparatus contains a first conveyor for making contact with a first surface of a respective one of the work pieces; and a second conveyor for making contact with a second surface, lying opposite the first surface, of the respective one of the work pieces. The first and second conveyors form an inlet mouth having a mouth upper part and a mouth lower part. The inlet mouth has a geometry which can be changed such that, in a first case, the mouth lower part protrudes beyond the mouth upper part and, in a second case, the mouth upper part protrudes beyond the mouth lower part. 
   In order to achieve the object, a geometry of the inlet mouth is provided which can be changed in such a way that, in a first case, the mouth lower part protrudes beyond the mouth upper part and, in a second case, the mouth upper part protrudes beyond the mouth lower part. 
   One advantageous development provides for it to be possible, for adaptation to different thicknesses of the flat work pieces, to set different spacings between the two conveyors. This is advantageous, for example if the conveyors are configured as flexible drives, in particular if rollers for driving and guiding a first flexible drive stand directly opposite those of the second flexible drive. 
   A configuration of this type exists, for example, if one of the two flexible drives is approximately a mirror image of the other and both are not displaced with respect to one another, as can certainly be provided if the conveyors are oriented horizontally. To this extent, the capability to be set to different thicknesses of the flat work pieces increases the area of application of the apparatus, in particular if it is equipped with displaceably disposed conveyors. 
   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 an apparatus for transporting flat work pieces, 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. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a diagrammatic, side-elevational view of, inter alia, an exemplary embodiment of an apparatus for transporting flat work pieces, conveyors being provided in the form of flexible drives which, in the case shown, are oriented horizontally and according to the invention; 
       FIG. 2  is a diagrammatic, side-elevational view of the subject matter according to  FIG. 1 , with the flexible drives, which are displaced with respect to one another and are inclined in a first direction; 
       FIG. 3  is a diagrammatic, side-elevational view of the subject matter according to  FIG. 1 , with the flexible drives, which are displaced with respect to one another and are inclined in a second direction; 
       FIG. 4  is an illustration of a detail from  FIG. 1  which has a configuration for adapting the apparatus to different thicknesses of the flat work pieces; and 
       FIG. 5  is a diagrammatic, side-elevational view of the apparatus according to  FIG. 1 , in which a device for driving the apparatus and for locking the conveyors are emphasized in relative positions to one another. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 1  thereof, there is shown an exemplary embodiment which is described in the following text, and has a first conveyor  1  formed by a first flexible drive  1 ′ and a second conveyor  2  formed by a second flexible drive  2 ′. The flexible drives  1 ′,  2 ′ substantially have a geometry that is mirrored along a conveying plane  3 , and they contain, at a respective first end and at a respective second end, a multiplicity of deflection rollers  4 . 1  to  4 . 4  which are wrapped around by endless belts  5 . The belts  5  of the first flexible drive  1 ′ form first conveying runs which face second conveying runs formed by the belts  5  of the second flexible drive  2 ′, and the first conveying runs make operating contact with a first surface of a flat work piece  6  which is to be conveyed. The second conveying runs make operative contact with a second surface, lying opposite the first surface, of the flat work piece  6  that is to be conveyed in a transport direction according to arrow T. In the present exemplary embodiment, the conveying runs extend from the deflection rollers  4 . 2  and  4 . 4  which are disposed downstream with regard to the transport direction according to arrow T to flexible drive guide rollers  7 . 1  and  7 . 2  which follow at a defined spacing downstream of the deflection rollers  4 . 1  and  4 . 3  which are disposed at the upstream end of the respective flexible drive and for their part are disposed at a defined spacing from the conveying plane  3 . 
   In the configuration shown in  FIG. 1 , the deflection rollers  4 . 1  and  4 . 2  and the flexible drive guide rollers  7 . 1  of the first flexible drive  1 ′ lie directly opposite the deflection rollers  4 . 3  and  4 . 4  and the flexible drive guide roller  7 . 2  of the second flexible drive  2 ′. This proves suitable for the case where the conveying runs, as shown in  FIG. 1 , are oriented horizontally. 
   It goes without saying that the two flexible drives  1 ′ and  2 ′ each have a multiplicity of the abovementioned belts  5  and a corresponding number of deflection rollers  4 . 1  to  4 . 4  and flexible drive guide rollers  7 . 1  and  7 . 2  which are disposed in a row transversely with respect to the transport direction according to arrow T between side cheeks  8 . 1  and  9 . 1  of two carriages  8  and  9  which will be described in greater detail in the following text. 
   As shown in  FIG. 2 , for the case where the downstream ends of the flexible drives  1 ′ and  2 ′ are lowered, the second flexible drive  2 ′ is preferably displaced, with respect to the first flexible drive  1 ′, in the transport direction according to arrow T. As shown in  FIG. 3 , for the case where the upstream ends of the flexible drives  1 ′ and  2 ′ are raised, the second flexible drive  2 ′ is in contrast preferably displaced, with respect to the first flexible drive  1 ′, counter to the transport direction according to arrow T. In both cases, the result of the displacement of the second flexible drive  2 ′ with respect to the first flexible drive  1 ′ in the respectively preferred direction is an improved entry behavior of flat work pieces which are fed to the apparatus, compared with a merely inclined configuration without corresponding displacement of the second flexible drive  2 ′ with respect to the first flexible drive  1 ′. 
   In a preferred refinement, the first conveyor, which is in the form of the first flexible drive  1 ′ here, can also be displaced in and counter to the transport direction according to arrow T. 
   In order to realize the displaceability, the first flexible drive  1 ′ is disposed on a first carriage  8  and the second flexible drive  2 ′ is disposed on a second carriage  9 . In each case only one of two side cheeks  8 . 1  and  9 . 1  of the two carriages  8  and  9  can be seen in the figures. The carriages  8  and  9  are carried by side walls, of which in turn only one side wall denoted by  10  can be seen in the figures. The side walls  10  have slots  11  which are oriented in the transport direction and into which guide pins  12  engage which are provided on the carriages  8  and  9 . In an alternative refinement, guide rollers, which are mounted on the carriages  8  and  9  so as to be rotatable are provided instead of the guide pins  12 . 
   A gear wheel  13  is mounted rotatably in at least one of the side walls  10  between the two carriages  8  and  9 . Teeth of a first rack toothing system  14  and a second rack toothing system  15  are provided on a respective one of the two carriages  8  and  9 , which teeth follow one another in or counter to the transport direction according to arrow T and engage with the gear wheel  13 . If one of the two carriages  8  and  9  is displaced in a first direction, this leads visibly to a simultaneous and identical displacement of the other carriage in a second direction opposite to the first direction. Here, the gear wheel  13  is an adjusting wheel, on which the first flexible drive  1 ′ and the second flexible drive  2 ′ roll simultaneously. 
   The two conveyors (in the form here of the first flexible drive  1 ′ and the second flexible drive  2 ′) can be locked in jointly assumed different pivoting positions, with respect to a geometric axis  16 , which extends transversely with respect to the transport direction according to arrow T. The geometric axis  16  preferably lies in the conveying plane  3  which is situated between the two conveyors  1  and  2 , and furthermore, preferably in the region of an inlet into a processing station which follows downstream of the apparatus and is shown as a press station  17  in the present exemplary embodiment. 
   In order to lock the two conveyors  1  and  2 , which are configured here as flexible drives  1 ′ and  2 ′, in jointly assumed pivoting positions with regard to the above-mentioned geometric axis  16 , at least one of the side walls is assigned a non-illustrated stationary support which has a plane-parallel region which is parallel to the side walls  10  and is penetrated by a slotted guide which is concentric with respect to the geometric axis  16  and of sufficient longitudinal extent. A projection  10 . 1  is provided on the at least one side wall  10  assigned to the support, which projection  10 . 1  reaches into the region of the slotted guide  18  when the conveyors  1  and  2  assume a defined working position, horizontally or inclined in one or the other direction. Disposed on the projection  10 . 1  of the at least one side wall  10  are, for example, pins  19  or else rotatably mounted rollers which engage into the slotted guide  18  in a defined working position of the conveyors  1  and  2  at a certain mutual spacing. The two conveyors  1  and  2  (in the form here of the flexible drives  1 ′ and  2 ′) can thus be set to common pivoting positions. In the present example, in order to lock them in one of these pivoting positions, a sufficient frictional fit is produced between the abovementioned support and the projection  10 . 1 , such as, for example, by a screw connection  20 , which presses the projection  10 . 1  and the above-mentioned support against one another. 
   For adaptation to different thicknesses of the flat work pieces  6 , different spacings can be set between the two conveyors  1  and  2 . In the present exemplary embodiment, in which the conveyors  1  and  2  are present in the form of the flexible drives  1 ′ and  2 ′, the spacings between the conveyors  1  and  2  are determined by the spacings of the conveying runs of the two flexible drives  1 ′ and  2 ′. To this extent, the flexible drives  1 ′ and  2 ′ contain adjustably disposed flexible drive guide rollers which determine the mutual spacing of the conveying runs of the flexible drives  1 ′ and  2 ′, for adaptation to different thicknesses of the flat work pieces  6 . 
   As provided in the present exemplary embodiment, it is sufficient if only the flexible drive guide rollers for guiding one of the two conveying runs are disposed adjustably. Accordingly, the flexible drive guide rollers  7 . 2  and the deflection rollers  4 . 4  of the second flexible drive  2 ′, which likewise serve as flexible drive guide rollers are disposed adjustably. 
   For this purpose, a first pivoting shaft  22  and a second pivoting shaft  23  are mounted freely rotatably in the side cheeks  9 . 1  of the second carriage  9  and are preferably pinned in each of the two pivoting shaft end sections with in each case a two-armed bearing lever  21  which, on a first lever arm  21 . 1  of the same, mounts in each case one end of an axle  7  which carries the deflection and flexible drive guide rollers  4 . 4  or of an axle  7  which carries the flexible drive guide rollers  7 . 2 . 
   As can also be gathered, in particular, from  FIG. 4 , in each case an adjustment pin  24  is set against the second lever arm  21 . 2  in such a way that, by exerting an adjusting force, it actuates the bearing lever  21  in terms of pivoting the first lever arm  21 . 1  away from the conveying plane  3 , to be precise counter to the effect of a non-illustrated force accumulator which acts on the first lever arm  21 . 1 , for example a compression spring. 
   The adjustment pin  24  is guided in a guide block  25  that is fastened to the side cheek  9 . 1  and is provided for the purpose with an appropriate hole, and in another appropriate hole in an angled-away bracket  26  of the side cheek  9 . 1 . Fastened to an end section of the adjustment pin  24  that faces the bracket  26  is a clamping plate  27  that is oriented transversely with respect to the end section. The clamping plate  27  carries an axle  28 , which is oriented perpendicularly with respect to the adjustment pin  24  and in relation to which a two-armed adjustment lever  29  can be pivoted. In the event of a corresponding pivoting of the adjustment lever  29  (in the clockwise direction in the case of the configuration according to  FIG. 4 ), the latter presses the axle  28  and thus the clamping plate  27  away from the bracket  26  (counter to the action of a spring  30 ), with contact between an end (specially shaped at this location) of an arm of the adjustment lever  29  and the bracket  26 , with the result that the adjustment pin  24  causes the bearing levers  21  which carry the axle  4  to pivot in the clockwise direction and the bearing levers  21  which carry the axle  7  to pivot in the counterclockwise direction, the deflection and flexible drive guide rollers  4 . 4  and the flexible drive guide rollers  7 . 2  being removed from the conveying plane  4 . 
   Using the adjustment device which have been explained to this extent for adapting the apparatus to different thicknesses of the flat work pieces  6 , it is possible to perform a defined setting for a defined thickness in a very simple manner, in that a part is clamped into the gap which is produced by the adjustment lever  29  between the bracket  26  and the clamping plate  27 , the part corresponding to the thickness of the flat work pieces. For this purpose, a part  31  of one of the flat work pieces  6  to be transported, which has been cut correspondingly to fit is preferably used. 
   For the optimum transmission of adjusting forces from the adjustment pin  24  onto the bearing lever  21 , a ball  32  is disposed between the latter which is inserted into a respective spherical cap formed on the adjustment pin  24  and on the second lever arm  21 . 2  of the bearing lever  21 . 
   To this extent, the bearing levers  21  which directly carry the deflection and flexible drive guide rollers  4 . 4  and the flexible drive guide rollers  7 . 2  are disposed so to be adjustable to different pivoting positions, and the deflection and flexible drive guide rollers  4 . 4  and the flexible drive guide rollers  7 . 2  are disposed so as to be adjustable, for adaptation to different thicknesses of the flat work pieces  6 . 
   The upstream ends of the conveyors  1  and  2 , which are configured in the form of the two flexible drives  1 ′ and  2 ′ in the present exemplary embodiment, form an inlet mouth  33  with a mouth upper part  33 . 1  and a mouth lower part  33 . 2 , and their downstream ends form an outlet mouth  34  with a mouth upper part  34 . 1  and a mouth lower part  34 . 2 . 
   As can be seen in  FIG. 1 , in the case of the apparatus being used with horizontally oriented conveyors, the mouth upper parts  33 . 1  and  34 . 1  are flush with the respectively associated mouth lower part  33 . 2  and  34 . 2 . Given appropriate displacement of the conveyors  1  and  2 , the respective mouth upper part  33 . 1  and  34 . 1  and/or the respective mouth lower part  33 . 2  and  34 . 2  can be displaced between positions in which first the mouth lower part  33 . 2  and  34 . 2  protrudes beyond the mouth upper part  33 . 1  and  34 . 1  and second the mouth upper part  33 . 1  and  34 . 1  protrudes beyond the mouth lower part  33 . 2  and  34 . 2 . 
   To this extent, the geometry of the inlet mouth  33  (and also of the outlet mouth  34 ) can be optimized with regard to a respectively required pivoting position, caused by the outlet level in a processing station that precedes the apparatus. 
     FIG. 2  shows a first example of this. In this case, the outlet of the flat work pieces  6  from a preceding processing station lies at a lower level than the entry into a processing station that is connected behind the apparatus, in this case the press station  17 . The conveyors  1  and  2  (the first flexible drive  1 ′ and the second flexible drive  2 ′ here) are locked for this purpose in a jointly assumed pivoting position, in which the conveyors  1  and  2  are pivoted downward with regard to the geometric axis  16  already explained. Here, the geometry of the inlet mouth  33  is optimized with regard to the pivoting position, to the extent that the mouth lower part  33 . 2  protrudes beyond the mouth upper part  33 . 1 . In this configuration, flat work pieces  6  that are ejected from a preceding processing station at a lower level than that of the geometric axis  16 , about which the conveyors  1  and  2  can be pivoted jointly, pass visibly unimpeded and as intended between the conveying runs of the two flexible drives  1 ′ and  2 ′. 
   The result here for the outlet mouth  34  is that the mouth upper part  34 . 1  protrudes beyond the mouth lower part  34 . 2  and, apart from the inclined configuration of the conveyors  1  and  2 , the transfer conditions from the latter to the following processing station which is configured as a press station  17  in the present example change only unsubstantially as a result of the displaced mutual position of the conveyors  1  and  2 , to the extent that, in order to achieve a protrusion of the mouth lower part  33 . 2  of the inlet mouth  33  by a defined amount beyond its mouth upper part  33 . 1 , in the preferred configuration for the positive displacement of both conveyors in opposite directions, the mouth upper part  34 . 1  and the mouth lower part  34 . 2  have to be displaced merely by half of the stated amount. 
     FIG. 3  shows a configuration for the case where a preceding processing station ejects flat work pieces  6  at a level, which is higher than the geometric axis  16 . 
   As a consequence, the conveyors  1  and  2  are pivoted upward with regard to the geometric axis  16 . This results in an optimized geometry of the inlet mouth  33  as a result of the two flexible drives  1 ′ and  2  being displaced in such a way that the mouth upper part  33 . 1  of the inlet mouth  33  protrudes beyond its mouth lower part  33 . 2 . 
   In this configuration, the work pieces  6  which are ejected from a preceding processing station at a level above that of the geometric axis  16  also pass visibly unimpeded and as intended between the two flexible drives  1 ′ and  2 ′. What was stated in conjunction with  FIG. 2  applies in the same way to the outlet mouth  34 . 
   Compared with  FIGS. 1 to 3 ,  FIG. 5  is supplemented by details and to this extent exhibits a locking apparatus  35 , by which the two carriages  8  and  9  which carry the flexible drives  1 ′ and  2 ′ can be locked in a respectively selected carriage position with respect to side walls  10  which carry them, and also exhibits drive devices for operating the flexible drives  1 ′ and  2 ′. 
   The abovementioned drive devices contain a double belt pulley  36  which is disposed concentrically with respect to the geometric axis  16 , is driven via an endless belt  37  by an operationally rotating wheel  38  of the downstream processing station configured here as a press station, and is wrapped around by a further endless belt  39 . The latter forms an upper run  39 . 1  which, starting from the double pulley wheel  36 , wraps around a deflection pulley  40  with its inner side, then wraps around a belt pulley  4 . 3 ′ which drives the deflection rollers  4 . 3  with its outer side, then wraps around a belt pulley  4 . 1 ′ which drives the deflection rollers  4 . 1  with its inner side, then wraps around a deflection pulley  41  with its outside, and then wraps around a further deflection pulley  42  with the inner side, from which deflection pulley  42  a lower run  39 . 2  of the belt  39  runs back to the double belt pulley  36 . The belt drive, which is preferably configured in this manner is preferably a toothed belt drive with endless toothed belts with toothing on the inner side and outer side. 
   Here, the double belt pulley  36  circulates in the counterclockwise direction. 
   In the exemplary embodiment explained to this extent, although the conveyors  1  and  2  are configured as flexible drives  1 ′ and  2 ′, the conveying runs of which moreover extend along the entire transport path, the scope of the invention also includes conveyors which are configured differently than this, such as flexible drives having in each case more than one conveying run extending along the transport path, or as roller conveyors or as combinations of conveyors which are configured from at least one roller conveying path and at least one flexible drive conveyor. 
   This application claims the priority, under 35 U.S.C. § 119, of German patent application No. 10 2004 015 592.5, filed Mar. 30, 2004; the entire disclosure of the prior application is herewith incorporated by reference.