Patent Publication Number: US-6698749-B2

Title: Device for feeding folded or unfolded signatures to a production line

Description:
CROSS-REFERERNCE TO RELATED INVENTION 
     Priority is claimed herein with respect to European Patent Application No. 00810921.7, filed in the European Patent Office on Oct. 5, 2000, the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The invention relates to a device for feeding folded or unfolded signatures to a production line. Such a device includes a conveying rotor that removes stacked signatures from an adjacent signature magazine and which is provided with a recess along the approximately circular circumference. The signature is partially lifted off the stack by a synchronously driven separating member by applying suction to the signature front edge in the conveying direction. The recess in the conveying rotor functions to hold the front edge of a signature and forms a conveying gap together with a conveying belt that makes contact along parts of the circumference and is moved in the same direction. 
     A device of this type is disclosed, for example, in Swiss Patent CH-A-598 107 and is used for a faster processing of the increasingly higher numbers of signatures. The aforementioned reference provides for a mutually interacting pair of suction devices on the stack front, used for the preliminary separation of the signatures. Thus, a signature gripped at the front edge by respectively one suction device, can be transferred to a conveying rotor provided with several recesses along the circumference and can be further deflected by the latter around a deflection roller located below the stack and in the direction of dropping off. The signature is withdrawn by being carried along between the conveying rotor and the deflection roller, so that after one signature has dropped off, the following suction device can grip the following signature by the fold. 
     On the one hand, it is questionable whether an increase in output can be achieved with this embodiment when on the other the reliability is reduced. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to create a device of the aforementioned type, which makes it possible to achieve an increase in output along with a high degree of reliability. 
     This object is solved according to the invention in that the separating element is provided with at least one suction head that is connected to a vacuum source. The suction head is attached to a control device control shaft, which is positioned parallel to the rotational axis of the conveying rotor and is attached to it, such that it can pivot. A structurally simple embodiment can be created in this way. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is subsequently explained further with the aid of two exemplary embodiments and by referring to the drawing, to which the reader is referred for all details not mentioned expressly in the description. 
     FIG. 1 is a front view of a schematic representation of the device according to the invention. 
     FIG. 2 is a view similar to FIG. 1 showing an alternative embodiment of the device according to the invention. 
     FIG. 3 is a view from the side of the device shown in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates a device  1  for feeding a production line with folded or unfolded signatures  2 , e.g. a feeder for a gathering and wiring stitching machine, an assembling machine for producing adhesive-bound books or a machine for placing inserts into newspapers. The device or feeder  1  comprises a conveying rotor  4  that rotates inside a frame  3  (see FIG. 3) and consists of a rotor shaft  5  with thereon attached conveying discs  6  that form a rotor. Each conveying disc  6  is provided along the circumference with two opposite arranged recesses  7 , which are arranged such that they are aligned one after another and parallel to the rotor shaft  5  if viewed over three conveying discs  6 . Respectively one separating element  8  is furthermore assigned to the recesses  7  that are arranged in a row. The separating element  8  is provided with several suction arms  10 , attached to a separating shaft  9 , which is positioned parallel to the rotor shaft  5  inside the conveying discs  6 . The suction arms have suction heads  11  that act upon the front edge in conveying direction F of a folded or unfolded signature  2 . The suction heads  11 , which are connected to a non-visible vacuum source, are supplied via a line  12  with a vacuum that is controlled, for example, with a rotary-spool valve  13  (see FIG.  3 ). The signatures  2 , stacked in an adjacent magazine  14 , are gripped by the suction heads  11  that rotate along with conveying rotor  4 . They are gripped at the folded, projecting edge facing the conveying rotor  4 , that is to say at the underside or front side of a signature  2  in the stack. During the removal in the form of a scaled flow, the signatures  2  are deflected in a downward direction around the deflection roller  15  that functions as a supporting element. In that way, the front edge of the signature  2  that is lifted off by the separating element  8  dips into the subsequent recess  7  without being released from the separating element  8 . This rotating along of the separating element  8  is shown in FIG. 1 with dashed lines in the effective range for the separating element  8 . The separating element  8  detaches from the front edge of the signature  2  as soon as this signature is gripped by an intake gap  17 , formed by the conveying discs  6  of conveying rotor  4  and one or several conveying belts  16  that rotate around the deflection roller  15 , and is conveyed further. 
     If the signatures  2  are to be separated during the removal from the magazine  14 , the deflection roller  15  is no longer needed as a supporting member on the underside of the stack. A conveying gap covering a range of approximately 120° is formed with the conveying belt(s)  16 , which circulates (circulate) around the deflection roller  15  and move(s) in the same direction along the circumference of the conveying rotor  4 . This conveying gap can be adapted to a changing scaled flow, with respect to height, as a result of the deflection roller  15  that supports itself on a spring  18 . The conveying belt(s)  16  is (are) guided around three deflection rollers  15 ,  19 ,  20 , of which the roller  20  is positioned on a tensioning lever  21  for tensioning the conveying belt  16 . The separating element(s)  8 , rotating along with the conveying rotor  4 , is (are) drive-connected to a control device  22 . For this, the control shaft  9  is provided at one end with a pinion gear  23 , which meshes with an additional toothed wheel  24  that is positioned on the conveying rotor  4 . A control lever  26  embodied as a detection member is positioned on the toothed wheel  24  and engages in a locally fixed (kidney-shaped) control track  25  that is connected to the frame  3 , by a freely turning roller  29  attached at the free end of control lever  26 . FIG. 1 shows a separating element  8  with a suction head  11  attached to the lowest signature  2 , as well as the respective position of the control device  22 . Immediately following this, a holding catch  27  that supports the stacked signatures  2  in the frontal edge region is pivoted downward (dash-dot position), so that the signature  2  that is suctioned against the separating element  8  can be pivoted at the folded edge around the deflection roller  15  and downward. As soon as the front edge is submerged at the circumference of conveying rotor  4  or has dipped into the recess  7 , assigned to the respective signature  2 , the holding catch or catches  27  rotate(s) back to the supporting operating position. The further course of the separating element  8  and the recess  7  and their position is shown with dashed line in FIG.  1 . In the process, it becomes obvious that the separating element  8  has more time and space available for transferring a signature  2  to the conveying rotor  4 , than is possible according to the CH-A-598 107. The movement path of a suction head  11  is given the reference  28  in FIG.  1 . The suction head(s)  11  is (are) located within the circumference of the conveying rotor  4 , from the moment the signature  2  is taken over at the intake gap  17  to the moment of discharge at the end of the conveying gap. 
     At the intake gap  17 , the movement direction for a signature  2  that is to be removed or deflected changes from a counter-rotating movement to movement in the same direction, relative to the rotational direction F of conveying rotor  4 . 
     The suction arms  10 , through which the vacuum is supplied, are attached at a right angle to the control shaft  9 , that is formed by a (circular) hollow space  44 , connected to the vacuum line  12  (FIG.  1 ). The connection to the suction heads  11  could also be realized in a radial direction to the pivoting axis of the control shaft  9 , forming an acute angle of less than 30°. 
     The shaft  30 , provided for actuating the holding catches  27 , is positioned parallel to the rotor shaft  5  and the control shaft  9  inside the frame  3 . Shaft  30  is provided on one end with a lever  31  that is pivoted via a roller  33  by a rotating cam disc  32  is positioned on the rotor shaft  5 . A toothed wheel  34  at the end of rotor shaft  5  drives the rotor shaft  5 . 
     FIGS. 2 and 3 show an alternative embodiment, wherein the embodiment shown in particular differs from the embodiment shown in FIG. 1 by an additional, controlled gripping device  35 . The gripping device  35  comprises a gripping shaft  36 , which extends inside the conveying discs  6 , parallel to the rotor shaft  5 , and is provided, for example, with three gripping arms  37 . The pivoting movements of the gripping shaft  36 , which are required for the open or closed position of the gripping device  35 , are executed with a gripping lever  38  that is attached to the gripping shaft end. They are realized by means of a control roller  40  that is positioned on the free end of lever  38  and which circulates on a locally fixed control track  39 . Control track  39  is connected to frame  3 . The recesses  7  along the circumference of the conveying rotor  4  or the conveying discs  6  have a pocket-shaped design with an expanded access opening, so that the signatures  2  that are deflected at the suction heads  11  can directly dip into the counter-rotating recess  7 . The wall  41  of recess  7  that follows in rotating direction F functions as a gripping support if the gripping device  35  is closed. For this, the gripping arms  37  have an end section  42 , bent at a right angle, which ensures a movement of the gripping arms  37  within the circumference of the conveying rotor  4 . The gripping support could also be, for example, a roller  43  that is positioned on the conveying discs  6  and acts in the manner of an anvil. 
     The invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art, that changes and modifications may be made without departing from the invention in its broader aspects, and the invention, therefore, as defined in the appended claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention.