Abstract:
A device for fastening functional parts in a component produced from a flat material, preferably sheet metal, by insertion and pressing, having several punching heads and opposing tool surfaces assigned to them. The component is located between the punching head and the pertinent opposing tool surface when the functional part is inserted. There are punching heads on a first tool part. The opposing tool surfaces are formed by thrust bearings which are provided on the top of a second plate-shaped tool part. The tool parts can be moved relative to one another for opening and closing the tool or the device and there are centering/guide and locking devices acting directly between the tool parts. When the tool parts are closed, the tool parts are directly centered and locked to one another. Each punching head is provided with an individual drive.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention relates to a device for feeding fastening functional parts to a component including a supply unit for the feeding of the functional parts.  
           [0003]    2. Description of the Prior Art  
           [0004]    “Functional parts” in the sense of the invention are in general elements, for example fasteners (for example, pins, rivets, nuts) which are fed into components. The feed of the fasteners, for example, pins, bolts and nuts into components or machined parts of sheet metal using so-called punching heads is knows as described in German Patent DE 43 43 154 A1.  
         SUMMARY OF THE INVENTION  
         [0005]    The object of the invention is to devise a device which, with a simplified structure, enables the feed, especially the simultaneous feed of several functional parts, specifically preferably a machined sheet metal part.  
           [0006]    The object of the invention is furthermore to devise a supply unit which, with a simplified structure, several machine components, for example, punching heads, can be supplied with the pertinent functional parts (for example, fasteners).  
           [0007]    By means of a centering and/or a guiding and/or locking device, in the device of the present invention, two tool parts which bear the punching heads and the pertinent thrust bearings, with the tool closed, are centered exactly to one another. These two tool parts are also connected by interlocking to one another such that the forces produced by the punching heads, when the functional parts are fed into the respective component, are completely accommodated between these tool parts and thus no forces are transferred to the outer elements of the device which bear the tool.  
           [0008]    The multiple feed limitations of the present invention have the advantage that with a simple structure, it would allow for the supply of several components, for example, punching heads, via their own delivery sections or supply tubes with the same functional parts. It would also allow the selection and feed of functional parts in the required correct orientation from a disordered set, utilizing only a single supply device, for example, a single spiral cup conveyor.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    The present invention will be explained below using the following figures.  
         [0010]    [0010]FIG. 1 is a very simplified schematic of the fundamental structure of the device of the present invention;  
         [0011]    [0011]FIG. 2 is in a perspective representation of one embodiment of the present invention showing the upper plate-shaped tool part of the device of FIG. 1;  
         [0012]    [0012]FIG. 3 is in a perspective representation of one embodiment of the present invention showing the lower plate-shaped tool part of the device from FIG. 1;  
         [0013]    [0013]FIG. 4 is in an enlarged partial representation of the present invention including a section of a workpiece produced form sheet metal with a fastener anchored in this workpiece in the form of a nut, together with a simplified partial representation of a punching head and its pertinent support;  
         [0014]    [0014]FIG. 5 is a simplified representation of a device for the separation and parallel feed of fasteners to several components, for example, punching heads;  
         [0015]    [0015]FIG. 6 is in an enlarged detailed representation of the multiple feed limitation of the device shown in FIG. 5; and  
         [0016]    [0016]FIG. 7 is another embodiment of the multiple feed limitation in a representation similar to what is shown in FIG. 6.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0017]    The device, shown in general in FIGS.  1 - 4 , is used in workpieces or machined sheet metal parts  1  to anchor fasteners  2  which in the embodiment shown are nuts, by insertion into prepared openings of the machined parts  1  and by subsequent pressing. The insertion and pressing of the fasteners  2  take place using punching heads  3  which are known in their execution and function to one skilled in the art (for example, German Patent DE 43 43 154 A1) and using a thrust bearing  4 . As is shown in FIG. 4, the fasteners  2  are provided in the guide  5  of the punching head. In each pass, the first fastener  2  in line is fed into the machined part  1  by means of a plunger  6  of the punching head  3  which, with its bottom or with an annular surface  3 ′ rests against the top of the machined part  1 . Then, by moving the punching head  3  down, the fastener  2  is anchored by pressing or deforming the material of the machined part  1  between the annular surface  3 ′ and the thrust bearing  4  in the machined part  3 . The fasteners  2  are fed to the respective punching head  3  or to the guide  5  by, for example, via a supply unit as in shown in FIG. 5.  
         [0018]    In the device, there are punching heads  3  with their pertinent drives  7  which are formed, for example, by hydraulic cylinders on the plate-shaped top part  8  of a tool  10 , where a fastener  2  is to be fed to the machined part  1 . The thrust bearings  4  are located on the top of the plate-shaped tool bottom part  9 , such that one thrust bearing  4  is opposite each punching head  3 . The top part  8  of the tool and the bottom part  9  of the tool are located in a press which is not shown. The bottom part  9  of the tool is stationary and the top part  8  of the tool can be moved by the opening and closing of the tool  10  which is formed by the two tool parts  8  and  9  perpendicular to its plate planes away from and towards the tool part  9 .  
         [0019]    As is shown in FIG. 1, the machined part  1 , after insertion into the tool  10 , lies essentially only on the thrust bearing  4  or on the opposing surface  4 ′ and possibly also on support elements which are not shown. After closing the tool  10 , the above-described feed and anchoring of the fasteners  2  into the component  1  by means of the punching heads  3  would then take place.  
         [0020]    The operation of the tool  10  has the advantage that in one pass, a host of fasteners  2  can be fed to the machined part  1  and/or attachment of the fasteners  2  is possible such that these fasteners  2  are oriented with their axes in different axial directions, and then also the punching heads  3  and the pertinent opposing surface  4 ′ can have an orientation which differs from punching head to punching head, and which corresponds to the respective orientation of the fasteners  2 .  
         [0021]    As shown particularly in FIGS. 2 and 3, on the top of the bottom part  9  of the tool there are centering pins  11  which, when the tool  10  is closed, fit into centering openings  12  in the top part  8 . Furthermore, on the surface of the bottom part  9  of the tool there are fork-shaped guide pieces  13  into which, with the tool  10  closed, guide elements  14  which project from the bottom of the top part  8  of the tool, fit by interlocking, with one another. Therefore, when the tool is closed, the tool parts  8  and  9  are also connected to one another by interlocking for the transfer of horizontal force components which are produced by the punching heads  3  which are tilted to the vertical.  
         [0022]    On the bottom part  9  of the tool, there are furthermore included locking brackets  16  which have locking openings  15  and which interact with bolts  18  which are actuated by actuators  17  (for example, hydraulic cylinders) such that with the tool  10  is closed, one bolt  18  at a time fits into each locking opening  15  and thus the two tool parts  8  and  9  are locked to one another and are secured against one another against opening of the tool  10 .  
         [0023]    In particular therefore, the upper tool part  8 , after inserting the machined part  1  using a press which is not shown, is moved down and in doing so, centered and guided first on the centering pins  11  which fit into the centering openings  12  until finally the guide pieces  14  engage the fork-shaped guide piece  13  and spacer elements  19  which are provided on the bottom of the top part  8 , and project over this bottom portion, come to rest against the corresponding spacers  20  of the bottom part  9  of the tool. Therefore, the top part  8  of the tool occupies a defined lower position to the tool part  9 . Activating the actuating elements  17  then locks the bolts  18  in the locking openings  15 . Subsequently, by actuating the drives  7 , the above-described feed and affixing of the fasteners  2  in the machined part  1  take place.  
         [0024]    To feed the fasteners to the different punching heads  3 , a supply unit  21  shown schematically in FIG. 5 is used. This embodiment essentially comprises an oscillating cup conveyor  22  which holds the fasteners in a disordered set and which conveys these fasteners in a given orientation to a guide rail  23  in which the fasteners  2  finally reach the feed limitation  24  via a lock  23 ′ which opens the guide  23  only for passage of the fasteners and otherwise blocks it again. The feed limitation in this embodiment has a total of four outputs to which one conveyor section formed by one flexible tube  23  at a time is connected for the fasteners  2 . The cross section of each conveyor section  25  is chosen such that the fasteners  2  are conveyed along this conveyor section while retaining a given orientation, in the embodiment shown, by a compressed air pulse. The conveyor sections  25  each lead to one punching head or to the pertinent rigid guide rail  5  of this punching head.  
         [0025]    [0025]FIG. 6 shows the feed limitation  24  in more detail. It consists essentially of a receiving channel  26  which is formed by the continuation of the guide  23  and in which four fasteners  2  tightly adjoining one another are accommodated in a given orientation. On one side of this channel  26  there are electrically triggerable pressure nozzle arrangements  27 , one nozzle arrangement  27  at a time fro each section  26 ′ of the channel  26  occupied by the fastener  2 . Opposite the pressure nozzle arrangement  27  is the inlet opening or the connection of the conveyor feed section  25  so that upon activation of the pertinent nozzle arrangement  27  by the compressed air pulse, which is indicated by the arrow D, and which radially enters the channel  26  from this nozzle arrangement, the pertinent fastener  2  is closed from its position in the channel  26  into the supply tube  25  and via the latter to the pertinent punching head  3  or another component.  
         [0026]    The manner of operation of the feed limitation will now be described. The initially empty channel  26  is charged with the number of fasteners  2  which corresponds to the selection positions by supplying these fasteners  2  via the guide  23  and the lock  23 ′. After complete charging of the channel  26 , either a simultaneous injection of the fasteners  2  into the pertinent supply tubes  25  or injection in a timed succession would occur.  
         [0027]    Wherever the channel  26  discharges into a supply tube  25 , an elastic catch  28  is provided. These catches  28  are made such that when the channel  26  is charged, they prevent the unwanted entry of the fasteners  2  into the supply tubes  25 , i.e., they block the supply tubes from the fasteners  2 . Only when the nozzle elements  27  are actuated, are the fasteners  2  injected into the supply tubes  25 , as the catches  28  press from overhead.  
         [0028]    [0028]FIG. 7 shows as another possible embodiment, a supply unit, which differs from the supply unit  21  in that the fasteners  2  are injected into the supply tubes  25  in timed succession. There is a charging channel  26   a  for this purpose which has only one position  26   a ′ for holding one fastener  2 , at which position in turn there is the electrically controllable nozzle arrangement  27 . Opposite the nozzle arrangement  27 , there is a slider  29  which can be moved by a drive  30  axially to the channel (double arrow E) and on which in the direction E of motion in succession there are openings or connections for the supply tubes  25 . In each position of the slider  29 , there is one opening of the supply tube  25  in the area of the charging position  26   a ′, opposite the pressure nozzle arrangement  27  so that, by activating the nozzle arrangement  27 , the pertinent fastener  2  can be delivered via the supply tube  25  to the pertinent component, for example, to the pertinent punching head  3 .  
         [0029]    The fasteners  2  are located in this version, for example, in a closed row in which the fasteners  2  tightly adjoin one another arranged in the channel  26   a,  the first fastener  2  of this row, via the slider  29 , entering the pertinent supply tube  25  and to reach the pertinent component.  
         [0030]    The invention was described above using embodiments. It goes without saying that numerous changes and modifications are possible without departing from the inventive idea underlying the invention.