Lubrication free connection

Abstract

A tenter clip has a jaw pivot shaft having a pair of molded bearing surfaces of superior strength, wear resistance and stability under high temperature operating conditions. The method for manufacture of the jaw pivot shaft includes knurling recesses formed in the shaft prior to applying plastic bearing material to the recesses by injection molding and finishing machining the pin by centerless grinding.

1 . A method of manufacturing a pivot pin for use in a high temperature environment comprising the steps of: 
 machining a pin to a predetermined oversize diameter    machining a pair of axially spaced relatively shallow reduced diameter recesses in said pin of an axial width suitable for registering with a pair a bearing surfaces of a member to which the pin is to be attached,    roughing up said recesses,    applying a cylindrical bearing sleeve of self lubricating thermoplastic compound to each of said recesses by injection molding, and    finishing machining the outside diameter of said pin including said bearing sleeves to a precise finished diameter by centerless grinding.    
   
   
       2 . The method of  claim 1  wherein said thermoplastic compound is polytetraflouraethylene.  
   
   
       3 . The method of  claim 1  wherein said thermoplastic compound has a melting point above 600 degrees F.  
   
   
       4 . A tenter clip comprising: 
 a clip body having an open side with a flat surface for supporting web material being fed into said open side and a pair arms spaced above and extending over said flat surface, each of said arms having a radially inward facing bearing surface,    a jaw,    a jaw pivot pin nonrotatably secured to said jaw and having an axially elongated knurled recess near each of its axially opposite ends, and    a sleeve of self lubricating high temperature resistant plastic molded into each of said recesses, said sleeves presenting radially outward facing cylindrical bearing surfaces on said jaw pivot pin mating, respectively, with said bearing surfaces on said arms.    
   
   
       5 . The tenter clip of  claim 4  wherein the outside diameter of said jaw pivot pin including said sleeves is machined to a uniform diameter.  
   
   
       6 . The tenter clip of  claim 4  wherein said high temperature resistant plastic has a melting point greater than 600 degrees F.  
   
   
       7 . The tenter clip of  claim 4  wherein said high temperature resistant elastic is polytetraflouraethylene.  
   
   
       8 . A cylindrical pivot pin comprising: 
 a shallow recess formed near each end of said pin, each of said recesses having a radially outward facing cylindrical surface which has been knurled and    a high temperature resistant, self lubricating plastic sleeve bonded to each of said roughed up cylindrical surfaces, each of said sleeves presenting a radially outward facing cylindrical bearing surface.    
   
   
       9 . The pivot pin of  claim 8  wherein said plastic is polytetraflouraethylene.  
   
   
       10 . The pivot pin of  claim 8  wherein the outer diameter of said pin including said sleeves is a uniform diameter.