Abstract:
A method for manufacturing includes a machine capable of operating with and without a stock material present and an apparatus responsive to each operation when the stock material is present and unresponsive when the stock material is absent.

Description:
BACKGROUND OF INVENTION  
         [0001]    This invention relates generally to counting in stamp press operations and, more particularly, to accurately counting the number of actual strokes accumulated on stamping dies.  
           [0002]    Generally accumulated number of strokes on a stamping die are collected by manually or automatically recording the number of total strokes achieved during each die run. The counted total of number of strokes includes actual strokes and false strokes. Actual strokes are defined as strokes performed by a stamping die with material stock present. False strokes are defined as strokes performed by a stamping die without material stock present. However, false strokes have little or no effect on the life of a stamping die.  
         SUMMARY OF INVENTION  
         [0003]    In one aspect of the invention, a method for manufacturing includes a machine capable of operating with and without a stock material present and an apparatus responsive to each operation when the stock material is present and unresponsive when the stock material is absent.  
           [0004]    In another aspect of the invention, an apparatus for determining a number of operations by a machine on a stock material is provided. The apparatus includes a strain gage configured to signal the operation of the machine and an optical sensor configured to verify the presence of stock material. The apparatus also includes an accumulator operably coupled to the strain gage and the optical sensor.  
           [0005]    In another aspect of the invention, a punch press system for manufacturing articles is provided. The system includes a cooperating punch section and die section for creating the articles from a stock material moving therethrough. The system also includes an apparatus for determining a number of operations by a machine on a stock material secured in at least one of the punch and the die section. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0006]    [0006]FIG. 1 is a cross-sectional view of an apparatus for determining a number of operations by a machine on a stock material.  
         [0007]    [0007]FIG. 2 is a cross-sectional view of a punch press system including the apparatus shown in FIG. 1.  
         [0008]    [0008]FIG. 3 is a cross-sectional view of a punch press system including the apparatus shown in FIG. 1. 
     
    
     DETAILED DESCRIPTION  
       [0009]    [0009]FIG. 1 is a cross-sectional view of an apparatus  10  for determining a number of operations by a machine (not shown) on a stock material (not shown in FIG. 1) i.e., number of actual strokes. Apparatus  10  includes a strain gage  12 , an optical sensor  14 , an accumulator  16 , and a display  18 . In an exemplary embodiment, strain gage  12 , optical sensor  14 , accumulator  16 , and display  18  are disposed substantially adjacent each other such that removal of at least one of strain gage  12 , optical sensor  14 , accumulator  16 , and display  18  will at least partially destroy apparatus  10 . In another embodiment, accumulator  16  and display  18  are disposed substantially distant, and strain gage  12  and optical sensor  14  are disposed substantially adjacent such that removal of at least one of strain gage  12  and optical sensor  14  will at least partially destroy apparatus  10 .  
         [0010]    In one embodiment, strain gage  12  is at least one of a wire strain gage and a foil strain gage configured to transmit a signal when the machine operates. Alternatively, any commercially available strain gage may be used which transmits a signal when a load on the strain gage surpasses a predetermined amount.  
         [0011]    In one embodiment, optical sensor  14  is at least one of a photo cell and a diode in conjunction with at least one of a lamp, a light-emitting diode, and a laser configured to transmit a signal when the stock material is present. Alternatively, any commercially available optical sensor may be used which transmits a signal when the presence of a material is detected.  
         [0012]    Accumulator  16  is configured to determine a number of operations based on receiving at least one signal from strain gage  12  and optical sensor  14 . Accumulator  16  is also configured to transmit a signal to display  18 . To determine a number of operations, accumulator  16  is configured to transmit a signal after receiving both a signal from strain gage  12  and a signal from optical sensor  14 .  
         [0013]    In one embodiment, display  18  is at least one of a mechanical display, a dial-type display, and an electric display configured to receive a signal from accumulator  16 .  
         [0014]    [0014]FIG. 2 is a cross-sectional view of a punch press system  20  including apparatus  10  (shown in FIG. 1). Punch press system  20  includes a cooperating punch  22  and die  24  section. Die section  24  includes a die shoe  26  including a receptacle  28  and a cavity  30  therein. Punch section includes a punch  31 . Punch press system  20  also includes a stock material  32  moving therethrough.  
         [0015]    In an exemplary embodiment, apparatus  10  is encapsulated in cavity  30  within receptacle  28  with a sealing material  34 . In one embodiment, sealing material  34  is manufactured from a resinous material, such as, for example, but not limited to, an epoxy. In another embodiment, apparatus  10  is secured in cavity  30  within receptacle  28  with at least one of a fastener, a weld, and a sealing material such that attempted removal of apparatus  10  will at least partially destroy apparatus  10 .  
         [0016]    In operation, apparatus  10  installs into die section  24  inside cavity  30  within receptacle  28  adjacent to die shoe  26  to count actual strokes accumulated during press operations. Stock material  32  is fed through press section  22  and die section  24  so that holes are punched and/or a structural change is formed in stock material  32  when punch  31  moves through stock material  32  into die shoe  26 . Optical sensor  14  detects the presence of stock material  32  and sends a signal to accumulator  16 . Strain gage  12  detects a load and sends a signal to accumulator  16 . Accumulator  16 , only after receiving both signals from optical sensor  14  and strain gage  12 , transmits a signal to display  18  and an actual stroke is counted. Accumulator  16  is not configured to transmit a signal unless both a signal from optical sensor  14  and a signal from strain gage  12  are present.  
         [0017]    [0017]FIG. 3 is a cross-sectional view of a punch press system  40  including apparatus  10  shown in FIG. 1. Punch press system  40  includes a cooperating die section  42  and punch section  44 . Punch section  44  includes a punch  46  including a receptacle  48  and a cavity  50  therein. Punch press system  40  further includes stock material  32  moving therethrough.  
         [0018]    In an exemplary embodiment, apparatus  10  is encapsulated in cavity  50  within receptacle  48  with a sealing material  52 . In one embodiment sealing material  52  is manufactured from a resinous material such as epoxy. In another embodiment, apparatus  10  is secured in cavity  50  within receptacle  48  with at least one of a fastener, a weld, and a sealing material such that attempted removal of apparatus  10  will at least partially destroy apparatus  10 .  
         [0019]    In operation, apparatus  10  installs into punch section  44  inside cavity  50  within receptacle  48  adjacent to punch  46  to count actual strokes accumulated during press operations. Stock material  32  is fed through punch section  44  and die section  42  so that holes are punched and/or a structural change is formed in stock material  32  when punch  46  moves through stock material  32  into die section  42 . Optical sensor  14  detects the presence of stock material  32  and sends a signal to accumulator  16 . Strain gage  12  detects a load and sends a signal to accumulator  16 . Accumulator  16 , only after receiving both signals from optical sensor  14  and strain gage  12 , transmits a signal to display  18  and an actual stroke is counted. Accumulator  16  is not configured to transmit a signal unless both a signal from optical sensor  14  and a signal from strain gage  12  are present.  
         [0020]    Daily maintenance or timing operations may require press systems  20  and  40  to operate without stock material  32  present. Apparatus  10  prevents these operations inadvertently counting towards the wear life of a stamping die. Running press systems  20  and  40  without stock material present, results in no signals transmitted from optical sensor or strain gage.  
         [0021]    The above-described apparatus for counting actual strokes accumulated on stamping dies is reliable, accurate, and tamper resistant. The apparatus integrates and cooperates easily into a variety of punch press systems. As such, a cost-effective and accurate apparatus is provided.  
         [0022]    While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.