Method to provide precision draw dimension of links

Abstract

A method of punching chain links for a power transmission chain from metal sheet material to ensure precise location of the apertures relative to the outer link contour of the link being created comprising the steps of piercing the metal sheet material to form the apertures and the back contour of the link at a first station. Piercing the metal sheet material to form link flanks at a second station. Shaving the apertures, the link flanks, and the back contour sequentially at a third same station as the metal sheet material is held stationary. Blanking the outer link contour to separate the link from the metal sheet material at fourth station.

1 . A method of punching chain links for a power transmission chain from metal sheet material comprising the steps of: 
 a) piercing the metal sheet material to form a pair of apertures, and a back contour of the link at a first station;    b) piercing the metal sheet material to form link flanks of the link at a second station;    c) shaving the apertures, the link flanks, and the back contour sequentially at a third same station as the metal sheet material is held stationary; and    d) blanking an outer link contour to separate the link from the metal sheet material at a fourth station.    
     
     
         2 . The method of  claim 1 , wherein the power transmission chain is a roller chain.  
     
     
         3 . The method of  claim 1 , wherein the power transmission chain is a silent chain.  
     
     
         4 . The method of  claim 1 , wherein the metal sheet is a coil and progresses through steps a) through d).  
     
     
         5 . The method of  claim 1 , wherein steps a) and b) are combined into one step, such that the metal sheet material is pierced to form the pair of apertures, the back contour, and the links flanks sequentially at one station as the metal sheet material is held stationary.  
     
     
         6 . A method of punching chain links for a power transmission chain from metal sheet material comprising the steps of: 
 a) piercing the metal sheet material to form a pair of apertures, a back contour of the link, and link flanks of the link at a first same station as the metal sheet material is held stationary;    b) shaving the apertures, the link flanks, and the back contour sequentially at a second same station as the metal sheet material is held stationary; and    c) blanking an outer link contour to separate the link from the metal sheet material at a third station.    
     
     
         7 . The method of  claim 6 , wherein the power transmission chain is a roller chain.  
     
     
         8 . The method of  claim 6 , wherein the power transmission chain is a silent chain.  
     
     
         9 . The method of  claim 6 , wherein the metal sheet is a coil and progresses through steps a) through c).  
     
     
         10 . The plurality of chain links in a power transmission chain created by the method of  claim 1 .  
     
     
         11 . The plurality of chain links in the power transmission chain created by the method of  claim 6 .  
     
     
         12 . A machine for creating a plurality of chain links for a power transmission chain from metal sheet material, wherein the machine operates by the steps of: 
 a) piercing the metal sheet material to form a pair of apertures, and a back contour of the link at a first station;    b) piercing the metal sheet material to form link flanks of the link at a second station;    c) shaving the apertures, the link flanks, and the back contour sequentially at a third same station as the metal sheet material is held stationary; and    d) blanking an outer link contour to separate the link from the metal sheet material at a fourth station.    
     
     
         13 . The machine of  claim 12 , wherein the power transmission chain is a roller chain.  
     
     
         14 . The machine of  claim 12 , wherein the power transmission chain is a silent chain.  
     
     
         15 . The machine of  claim 12 , wherein the metal sheet is a coil and progresses through steps a) through d).  
     
     
         16 . The machine of  claim 12 , wherein steps a) and b) are combined into one step, such that the metal sheet material is pierced to form the pair of apertures, the back contour, and the link flanks sequentially at one station as the metal sheet material is held stationary.