Universal Joint Lubrication Improvements

Abstract

A universal joint has a ball retainer having a retainer body made of a structurally rigid material and a relatively soft elastomeric seal bonded to the body at an axial end in a recess so as to wipe lubricant back on the ball that is retained by the body. Cavity plates in a housing of the universal joint partially close off lubricant reservoir recesses to retain lubricant in the reservoirs and act as wear plates that stabilize the centering plate orbiting in the recess. Seals can be provided between the retainer and the ball socket, between the centering plate and the wear plates and between the wear plates and the cavity plates. Passageways connect the center cavity of the housing with the ball sockets through an orifice.

1 . In a universal joint of the type having a pair of yokes pivotally connected to one another with a centering apparatus between the yokes including at least one ball received within a ball socket, the improvement wherein the ball is retained in the ball socket by a ball retainer having: (a) a retainer body that is rigid and retained in the ball socket by a retainer ring that captures the retainer body axially in the socket and permits the retainer body to rotate relative to the socket; and (b) an elastomeric seal bonded to an axially-facing end surface of the retainer body so as to wipe against a spherical surface of the ball as the ball rotates relative to the ball retainer.  
   
   
       2 . The universal joint of  claim 1 , wherein the seal is received in a recess in an outer end face of the retainer body.  
   
   
       3 . The universal joint of  claim 1 , wherein a spherical surface is formed on the retainer body that mates with a spherical surface of the ball, and a spherical surface is formed on the seal that mates with the spherical surface of the ball.  
   
   
       4 . The universal joint of  claim 1 , wherein in a free state the seal extends further radially inward than the retainer body.  
   
   
       5 . The universal joint of  claim 1 , wherein the seal has a U-shaped cross-section with two free legs connected by a bridging leg, wherein one of the legs and the bridging leg are bonded to the axially-facing end surface of the retainer body.  
   
   
       6 . The universal joint of  claim 1 , wherein the seal has an inner leg that extends inward radially of the retainer body.  
   
   
       7 . The universal joint of  claim 1 , wherein the seal has an inner leg that extends axially away from the retainer body and radially inward from the retainer body.  
   
   
       8 . The universal joint of  claim 1 , wherein in an extreme position of the universal joint the seal provides a soft stop that limits further angulation of the universal joint.  
   
   
       9 . The universal joint of  claim 1 , wherein the seal provides an edge that wipes lubricant on the spherical surface of the ball rearwardly relative to the ball back into the ball socket as the ball rotates out of the seal.  
   
   
       10 . The universal joint of  claim 1 , wherein when the retainer is assembled to the ball, the ball expands the diameter of the elastomeric seal.  
   
   
       11 . The universal joint of  claim 1 , wherein the seal has a rounded outer edge that wipes against the ball.  
   
   
       12 . The universal joint of  claim 1 , further comprising a seal between the retainer body and the ball socket.