Abstract:
A punching mechanism for punching press with multiple linking rods, wherein an eccentric device drives at least one rocking arm, the rocking arm driving a hinged lever-type swing arm, thereby a linking arm joined to the swinging arm drives an acting arm to lower an upper mold that is connected to the acting arm; the linked movement of the arms produce delay effects to the punching cycle, reducing vibration during punching process and extending time for flexible forming of materials, and reducing material stress.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    (a) Field of the Invention  
           [0002]    The present invention relates to a punching mechanism comprising of a plurality of linking rods, for applications to a punching press machine.  
           [0003]    (b) Description of the Prior Art  
           [0004]    A punching press machine is a processing machine using reciprocal impact punches. A punching mechanism is the essential part for the performance of the punching press machine. At the present, regular punching mechanisms include uniform-motion models and toggle models.  
           [0005]    The punching process and return process of the aforementioned uniform motion models are in equal operational speed, higher the speed cause higher efficient. However, the high speed punching produce conspicuous vibration and noise and the high speed return processes will also result in insufficient time for feeding materials. Therefore, uniform-motion design is not practical for the high -speed operation. Besides, a shorter period of forming process will result in stress in the material and poorer forming quality.  
           [0006]    The toggle models operation emphasis on low-speed processing to achieve better cutting and pressing effects, but because it has longer punching movement, the conspicuous vibration and noise are still generated during operation, it also has shorter period for return process.  
         SUMMARY OF THE INVENTION  
         [0007]    The object of present invention is to provide a punching mechanism for punching press machine with multiple linking rods, using the transmission delay of the linking rods to to the punching process, thereby reducing vibration in punching operation, lengthening time for feeding materials, extending time for forming of materials, and reducing stress for materials. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0008]    [0008]FIG. 1 is a schematic view of the invention.  
         [0009]    [0009]FIG. 2 is a schematic view of the invention in operation.  
         [0010]    [0010]FIG. 3 is a table of comparison of cycle curves between the invention and a conventional model and a toggle model.  
                                             BRIEF DESCRIPTION OF NUMERALS                                    10 eccentric device   11 eccentric wheel           12 driving arm   13 lower end           14 upper end   15 linking rod           20 rocking arm   21 driving end           22 rocking arm end   30 swinging arm           31 hinge position   32 swinging arm end           33 hinging end   40 linking arm           41 linking end   42 driving end           50 acting arm   51 acting end           52 operating end   60 upper mold           70 machine base   71 groove           80 guide unit   81 chute           82 guidepost   83 chute           84 guide post   85 accommodating chamber                      
 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0011]    [0011]FIG. 1 shows a schematic view of the invention, which comprises a guide unit  80 , a set of eccentric devices  10 , two rocking arms  20 , two swinging arms  30 , two linking arms  40 , two acting arms  50  and an upper mold  60 .  
         [0012]    On top of the guide unit  80  is a chute  81 , the chute  81  being assembled with a fixed guide post  82 ; at a lower part of the guide unit  80  is a chute  83 , the chute  83  being assembled with a fixed guide post  84 . The guide unit  80  has an accommodating chamber  85 . Said guide posts  82 ,  84  are installed on a machine base  70 .  
         [0013]    The eccentric device  10  comprises an eccentric wheel  11  and a driving arm  12 . The eccentric wheel  11  is installed inside the accommodating chamber  85  of the guide unit  80 , and is rotated by driving force. The driving arm  12  has a lower end  13  and an upper end  14 , the lower end  13  being joined to the eccentric wheel  11 , the upper end  14  having a linking rod  15 , two ends of the linking rod  15  being joined to the guide unit  80 .  
         [0014]    Each of the rocking arms  20  has a driving end  21  and a rocking arm end  22 . The driving end  21  is joined to an end of the linking rod  15 . Using their hinge position  31  at their middle part, the swinging arms  30  are installed on the machine base  70 , the swinging arms  30  capable of swinging like levers using the hinge position  31 . At two ends of the hinge position  31  of the swinging arm  30  are the formation of a swinging arm end  32  and a hinging end  33 , the swinging arm end  32  being connected to the rocking arm end  22  of the rocking arm  20 . Importantly, the rocking arms  20  are not fixed onto the machine base  70 .  
         [0015]    The linking arm  40  has a linking end  41  and a driving end  42 , the linking end  41  being joined to the hinging end  33  of the swinging arm  30 , the driving end  42  being extended into a specified chute  71  on the machine base  70 . Importantly, the linking arm  40  is not fixed onto the machine base  70 .  
         [0016]    The acting arm  50  has an acting end  51  and an operating end  52 . The acting arm  50  is accommodated in the chute  71  on the machine base  70 , its acting end  51  being joined to the driving end  42  of the linking arm  40 . Since the acting arm  50  is accommodated in the chute  71 , the acting arm  50  is capable of movement only along the chute  71 .  
         [0017]    The upper mold  60  is made according to processing requirements, and is assembled to the operating end  52  of the acting arm  50 .  
         [0018]    Please refer to FIG. 2. In operation, rotating of the eccentric wheel  11  of the eccentric device  10  raises the driving arm  12 , which in turn drives and elevates the guide unit  80 . Because of the assembly of the guide posts  82 ,  84  and the chutes  81 ,  83  on upper and lower parts of the guide unit  80 , the guide unit  80  is capable of stable movement. Elevating of the guide unit  80  drives and elevates the linking rod  15  in a steady way, thereby elevating the driving end  21  of the rocking arm  20 .  
         [0019]    Since the rocking arm  20  is not fixed onto the machine base  70 , elevating of the driving end  21  of the rocking arm  20  does not drive the rocking arm end  22 . When the driving end  21  of the rocking arm  20  is elevated to a specified height, the rocking arm end  22  of the rocking arm  20  is driven to push the swinging arm end  32  of the swinging arm  30 . Since the swinging arm  30  is installed onto the machine base  70 , the hinging end  33  of the swinging arm  30  is activated to drive the linking arm  40 .  
         [0020]    The linking arm  40  not being fixed onto the machine base  70 , and the driving end  42  extending into the chute  71  of the machine base  70 , the linking arm  40  will swing, and the driving end  42  will reach into the chute  71 . Thereby, the acting arm  50  is pushed to move and push the upper mold  60  to punch and press on a work piece (not shown in drawings).  
         [0021]    In the aforementioned punching process, since the rocking arm  20  is driven by the eccentric device  10 , it does not simultaneously drive the swinging arm  30 , so the linking arm  40  and the acting arm  50  will not moved immediately. In other words, the mechanism comprising the eccentric devices  10  and the arms pulls the upper mold  60  to its starting position; but when the upper mold  60  starts to lower again, there will be a time lag, whereby the work piece (not shown in drawing) has a sufficient feed time to reach a working position.  
         [0022]    Furthermore, since the linking parts of both the rocking arm  20  and the linking arm  40  are drove by partial force, the entirety of acting force produced by the eccentric devices  10  will not be transmitted by way of the upper mold  60  to the work piece, thereby reducing impact and noise.  
         [0023]    After the eccentric devices  10  have driven the arms and lowered the upper mold  60  to its lowest position for punching process, since the rocking arm  20  and the linking arm  40  not being fixed, the initial driving force of the eccentric devices  10  does not drive and elevate the upper mold  60 . In other words, the contact time between the upper mold  60  and the work piece (not shown in drawing) is lengthened to produce better shaping on the processed part of the work piece, this reduce stress action of materials and effectively remove burrs resulting from the process. Therefore, the present invention has better processing performance in its application.  
         [0024]    As shown in FIG. 3, a cycle curves of the present invention and the conventional uniform motion models and toggle models. It is known from the curves in each 360-degree cycle (driven by the eccentric device), the present invention has a shorter cycle length and more gradual cycle curves, therefore prove the delay effects in present invention and it do reduce vibration and increase material answering time in process.  
         [0025]    It is to be understood that the above description covering the preferred embodiment and design drawing of the present invention shall not be used to restrict the claim of the invention, and that all equivalent art, approaches, or modifications or variations made accordingly shall be included in the subject claim.