Pivot pins for a slack adjuster in a braking system and method of greasing the pins

Abstract

A kit of parts to prevent seizing of yoke and link pins of slack adjusters in the braking system of highway tractors includes a replacement yoke pin and a replacement link pin. Both the replacement pins have a hexagonal head for gripping with a suitable wrench or socket tool to rotate the pins. The replacement yoke pin also includes a longitudinal bore which communicates between an outer surface of the shaft of the pin and a nipple at the head to introduce grease to the outer surface of the shaft of the pin. The combination of the longitudinal bore to introduce the grease and the hexagonal head for rotating the pin permits the grease to be thoroughly dispensed about the pin and thereby prevent seizing.

1 . A greasable pivot pin comprising: 
 an elongate shaft having a smooth cylindrical outer surface;    a head mounted at one end of the shaft which is hexagonal in cross section and which is larger in diameter than the shaft;    a transverse aperture extending through the shaft at an opposite end from the head for receiving a locking pin therethrough;    a longitudinal bore extending through the shaft in a longitudinal direction thereof;    at least one transverse bore communicating between the longitudinal bore and the outer surface of the bore; and    a nipple supported on the head for communication with the longitudinal bore to introduce grease into the transverse bore at the outer surface of the shaft through the longitudinal bore.    
   
   
       2 . The pivot pin according to  claim 1  wherein the shaft has a diameter of ½ an inch.  
   
   
       3 . The pivot pin according to  claim 1  wherein the head has a diameter of 9/16 th  of an inch.  
   
   
       4 . The pivot pin according to  claim 1  wherein there is provided a pair of the transverse bores diametrically opposed from one another midway between the head and the transverse aperture.  
   
   
       5 . A kit of parts for use on a slack adjuster of a braking system of a highway tractor; the kit of parts a yoke pin and a link pin, the yoke pin comprising: 
 an elongate shaft having a smooth cylindrical outer surface;    a head mounted at one end of the shaft which is hexagonal in cross section and which is larger in diameter than the shaft;    a transverse aperture extending through the shaft at an opposite end from the head for receiving a locking pin therethrough;    a longitudinal bore extending through the shaft in a longitudinal direction thereof;    at least one transverse bore communicating between the longitudinal bore and the outer surface of the bore; and    a nipple supported on the head for communication with the longitudinal bore to introduce grease into the transverse bore at the outer surface of the shaft through the longitudinal bore;    the link pin comprising an elongate shaft having a smooth cylindrical outer surface;    a head mounted at one end of the shaft which is hexagonal in cross section and which is larger in diameter than the shaft; and    a transverse aperture extending through the shaft at an opposite end from the head for receiving a locking pin therethrough.    
   
   
       6 . The kit of parts according to  claim 5  wherein the shaft of the yoke pin has a diameter of ½ an inch and the shaft of the link pin has a diameter of ¼ of an inch.  
   
   
       7 . The kit of parts according to  claim 5  wherein the head of both the yoke pin and the link pin have a diameter of 9/16 th  of an inch.  
   
   
       8 . The kit of parts according to  claim 5  wherein there is provided a pair of the transverse bores diametrically opposed from one another midway between the head and the transverse aperture of the yoke pin.  
   
   
       9 . A method of greasing a yoke pin in a slack adjuster, the method comprising: 
 providing a yoke pin comprising: 
 an elongate shaft having a smooth cylindrical outer surface;  
 a head mounted at one end of the shaft which is hexagonal in cross section and which is larger in diameter than the shaft;  
 a transverse aperture extending through the shaft at an opposite end from the head for receiving a locking pin therethrough;  
 a longitudinal bore extending through the shaft in a longitudinal direction thereof;  
 at least one transverse bore communicating between the longitudinal bore and the outer surface of the bore; and  
 a nipple supported on the head for communication with the longitudinal bore to introduce grease into the transverse bore at the outer surface of the shaft through the longitudinal bore;  
   inserting grease into the nipple;    gripping the head with a suitable wrench-like tool;    rotating the yoke pin about a longitudinal axis thereof.    
   
   
       10 . The method according to  claim 9  wherein the shaft has a diameter of ½ an inch.  
   
   
       11 . The method according to  claim 9  wherein the head has a diameter of 9/16 th  of an inch.  
   
   
       12 . The method according to  claim 9  wherein there is provided a pair of the transverse bores diametrically opposed from one another midway between the head and the transverse aperture.