Abstract:
A feeder for feeding printed products includes a casing comprising a one-piece frame including two spaced apart end plates and a plurality of crosspieces connecting the two end plates. At least one shaft is arranged on the end plates. At least one positioning element is arranged on the end plates to position the shaft on the end plates.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority of European Patent Application No: 06405320.0, filed on Jul. 26, 2006, the subject matter of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Field of Invention 
     The present invention relates generally printed products, and more particularly to a feeder device for positioning the printed products along a conveying path. 
     2. Description of the Related Art 
     In the printing industry, a feeder is conventionally used to pull off and convey printed products from a stack into a collector, where the printed products may be processed in various ways. For example, a feeder can be used to supply cards or merchandise samples to be glued on printed products. The feeder can also be used to supply and insert ads into newspapers and magazines. In all cases, these feeders must meet high quality standards with respect to capacity and operational safety. Also, since feeders are generally manufactured in large quantities, an easy and cost-effective large-scale production of these feeders should also be possible. 
     A conventional feeder of the above-described type is disclosed in Swiss Patent Application 493 337 A, wherein a gripping element is used to pull signatures from a stack and an expanding element is used to open the signatures. The signatures are then dropped onto a sword and later conveyed from the sword onto a conveying chain. The gripping element and the expanding element are arranged on shafts, which are positioned on two side plates that are joined by crosspieces. 
     Another conventional feeder used for supplying printed products to a conveying channel is disclosed in European Patent Application 1 231 176 B. In this feeder, a shaft is positioned on two end plates on the sides of a frame and is used for pulling printed products from a stack. The shaft includes grip disks that are fixedly mounted thereon, so as to rotate along with the shaft. The grip disks are provided with grippers, which pull respectively one printed product from the stack. 
     The conventional feeders described above are typically expensive to assembled and manufacture. What is needed is a feeder that can be produced and assembled at lower expense than the conventional feeders. 
     SUMMARY OF THE INVENTION 
     One embodiment of the present invention provides a feeder for feeding printed products, the feeder comprising a casing comprising a one-piece frame including two spaced apart end plates and a plurality of crosspieces connecting the two end plates; at least one shaft arranged on the end plates; and at least one positioning element arranged on at least one end plate to position the at least one shaft on the at least one end plate. 
     Accordingly, unlike conventional feeders, the end plates of the feeder of the invention are not screwed to the crosspieces, but are connected non-detachably to the crosspieces. According to a further embodiment, the end plates are welded to the crosspieces. Consequently, the basic frame, and thus also the casing, have fewer joining locations and are considerably more stable than a casing whose components are screwed together. According to a further embodiment, the shaft is positioned in the casing via at least one positioning element arranged on at least one of the end plates, so that the shaft can be installed and later replaced easily. The one-piece frame can be produced cost-effectively using sheet metal, plastic, or a precision casting material. The one-piece frame according to embodiments of the invention is more rigid and self-supporting than conventional frames made of thin sheet metal. The one-piece frame can also be manufactured inexpensively in large scale. Further, the installation is faster and easier since the shaft can be inserted from the outside of the end plates, which is advantages over conventional feeders in which the end plates are screwed to the crosspieces during the initial installation and thus need to be detached in order for shaft to be replaced. 
     According to another embodiment of the invention, at least one end plate includes a recess for inserting the shaft, wherein this recess may be a slot. The installation and replacement of the shaft is particularly easy if the slot is open along one edge of the end plate. For example, if the slot is open along a lower edge of the end plate, the shaft can be inserted from the bottom into the casing and/or the basic frame. 
     According to another embodiment of the invention, the positioning element includes a positioning plate attached to one of the end plates. In a further embodiment, this positioning plate also acts as a shaft bearing. 
     According to another embodiment of the invention, two positioning plates are attached to one of the end plates, where one of the positioning plates is used for positioning a so-called A shaft, while the other positioning plate is used for positioning a B shaft and/or a C shaft. 
     According to a further embodiment of the invention, one of the end plates includes a box, which may include a control unit and may be used for attaching operating elements as well as a controller. 
     The feeder according to the various embodiments of the invention can be manufactured cost-effectively and in large scale, while still ensuring a high operational safety. Further, according to embodiments of the invention, the components of the feeder including the shaft can also be replaced relatively easily. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the invention will be further understood from the following detailed description of an embodiment of the invention with reference to the accompanying drawings. 
         FIG. 1  depicts a three-dimensional view of a feeder according to an embodiment of the invention. 
         FIG. 2  depicts a different three-dimensional view of the feeder of  FIG. 1 . 
         FIG. 3  depicts a three-dimensional view of the one-piece frame according to an embodiment of the invention. 
         FIG. 4  depicts a different three-dimensional view of the one-piece frame from that shown in  FIG. 3 . 
         FIG. 5  depicts an exploded three-dimensional view of the feeder according to an embodiment the invention, showing individual components of the feeder separately. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts a feeder  1  having a casing  2  with an A shaft  11 , a B shaft  12 , and a C shaft  13  positioned therein, according to an embodiment of the present invention. In this embodiment, these shafts are driven by a drive  15  having a drive element  21  in the form of a toothed belt that is fitted around a toothed gear  23  and is connected to the A shaft  11 , the B shaft  12 , and the C shaft  13 , via toothed gears  22 ,  25 , and  26 , respectively. A toothed gear  24  is positioned displaceably on a bracket  34  (shown in  FIG. 3 ) and is used for the tensioning of the drive element  21 . Also positioned inside the casing  2  are guide elements  14  and  16  for guiding the withdrawn sheets, as well as an end stop  17  and a diverter  18  (all shown in  FIG. 5 ). The shafts  11 ,  12  and  13 , as well as the other parts arranged and positioned inside the frame  2 , are generally known in the related art and need not be explained in further detail. Depending on the type of feeder  1  that is used, the shafts  11 ,  12 ,  13  may take on different designs or, alternatively, may be omitted altogether. Embodiments of the invention utilizing only one shaft or more than three shafts are also conceivable. 
     As best shown in  FIGS. 3-4 , the casing  2  includes a one-piece basic frame  3 , provided with a first end plate  4  and a second end plate  5  on opposite sides, which are fixedly joined to one another by a first crosspiece  6 , a second crosspiece  7 , as well as a third crosspiece  8 . According to one embodiment, the two end plates  4  and  5  are welded to the crosspieces  6 ,  7  and  8 . However, the end plates  4  and  5  can also be joined to the crosspieces  6 ,  7  and  8  in a different manner, e.g., via glue. In other embodiments, it is also conceivable for the casing to be made of plastic or precision casting material. The basic frame  3  may also be produced from comparatively thin sheet metal and especially metal plate. 
     The separate end plates  4  and  5  on the sides are respectively reinforced by a bent section  9  and/or  10 , as shown in  FIG. 3 . The bent section  10  on the second end plate  5  is designed to hold an attachment  42 , shown in  FIG. 2 , which forms a box  31  together with a side flap that is not shown herein. This attachment  42  serves to accommodate an input unit  30  as well as other operating elements. A control unit  32 , and other elements such as a controller, may also be installed inside the box  31 . A removable front panel  27  ( FIG. 1 ) functions to cover an opening between the crosspieces  7  and  8 . 
     According to an embodiment of the invention, for feeding in the printed products, which are not shown herein, the top of the casing  2  may include a stack support  28  on which adjustable end stops  43  are arranged (see  FIGS. 1-2 ). In addition, a pivoting table  29  may also be arranged on the casing  2 . 
     Referring now to  FIG. 3 , according to an embodiment, the first end plate  4  is provided with a longer slot  35  and a shorter slot  36  for the installation and replacement of shafts  11 ,  12  and  13 . Opposite the longer slot  35  are arranged a slot  38  and a circular opening  41 , which, together with the slot  35 , are designed to accommodate the A shaft  11  and the B shaft  12 . The shorter slot  36  and a slot  37  arranged opposite thereof serve to accommodate the C shaft  13 . An upper positioning plate  19  and a lower positioning plate  20  ( FIG. 1 ) are further attached to the first end plate  4  for positioning the shafts  11  to  13 , wherein corresponding bores  39  are provided for screwing the plates  19  and  20  to the first end plate  4 . Pivot bearings for these shafts  11  to  13 , which are not shown herein, are provided on the second end plate  5 , in the region containing the slots  37  and  38  and the recess  41 . Corresponding bores  40  are again provided for attaching these parts with screws. Finally, the first end plate  4  contains a recess  33  ( FIG. 3 ) for accommodating the drive  15 . 
     The A shaft  11  is installed by inserting one end of the shaft  11  end (not shown herein) from the inside of the base frame  3  into the recess  41  and by inserting the other end of the shaft  11 , together with the upper positioning plate  19 , into the lower end of the slot  35  and pushing it upward. Once it is in a predetermined position, the plate  19  is attached to the end plate  4 , for example by screwing it on, wherein the positioning plate  19  additionally functions to reinforce the end plate  4 . Finally, the bearing element for the A shaft  11 , which is not shown herein, is attached to the second end plate  5 . 
     The B shaft  12  is also installed from the bottom of the basic frame  3  by inserting one end of the B shaft  12  through the slot  38  and inserting the other end through the slot  35 . The B shaft  12  is positioned in the first end plate  4  with the aid of the elongated lower positioning plate  20 , provided with a slot  44  having an opening at the bottom, as shown in  FIG. 5 . The C shaft  13  is similarly installed by making use of the slots  36  and  37 , as well as a slot  45  in the lower positioning plate  20 . The C shaft  13  is provided with bearings  50 ,  51  at its opposite ends, which are attached with screws to the inside of the end plate  4 . The B shaft  12  is similarly attached to the end plate  4 . The B shaft  12  and the C shaft  13  can thus be dismantled easily for a replacement. For the replacement of the A shaft  11 , the B shaft  12  must first be removed and then the upper positioning plate  19  detached. The shafts  11 ,  12  and  13  consequently can be installed and replaced without requiring changes to the basic frame  3 , meaning the stability of the self-supporting basic frame  3  is maintained at all times. 
     It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and that the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.