Knuckle and bushing assembly

Abstract

A suspension coupling for use in a vehicle suspension system the suspension coupling including a knuckle and bushing assembly wherein the knuckle member is a cast aluminum piece having a passage for receiving a two-piece bushing having a formed, metal inner member and a molded, elastomeric outer member having extension members at each end. The bushing member is press-fit into the knuckle member and exhibits higher stiffness in the radial and axial directions and lower stiffness in the torsional and conical directions.

1 . A bushing for a knuckle and bushing assembly for use in a suspension system of a vehicle, the bushing comprising:
 an axial passage extending from a first end of the bushing to a second end of the bushing in an x-direction,   a metal inner member having a length in the x-direction and generally having axial symmetry, the length of the metal inner member having a first end region proximate the first end of the bushing and a second end region proximate the second end of the bushing, a central region proximate the middle of the length, a first narrow region between the first end region and the central region and a second narrow region between the second end region and the central region, wherein the first and second narrow regions have a thickness less than a thickness of the central region and less than a thickness of the first and second end regions;   an elastomeric outer member over the metal inner member, wherein the elastomeric outer member covers substantially the entire length and is attached to substantially the entire length of the metal inner member, wherein the elastomeric outer member has first and second end regions, a central region covering the central region of the metal inner member, a first ear between the first end region and the central region of the elastomeric outer member, and a second ear between the second end region of the outer member, wherein the outer member has a first axial opening generally in the axial direction between the first ear and the first end region of the outer member, a second axial opening generally in the axial direction between the second ear and the second end region, a first annular reduced portion located in an exterior surface of the bushing between the first ear and the central region of the outer member, and a second annual reduced portion located in an exterior surface of the bushing between the second ear and the central region of the outer member.   
     
     
         2 . The bushing of  claim 1  wherein the bushing includes a shaped elastomeric body. 
     
     
         3 . The bushing of  claim 1  wherein the bushing includes a molded rubber body. 
     
     
         4 . The bushing of  claim 1  wherein the bushing includes a molded natural rubber body. 
     
     
         5 . The bushing of  claim 1  wherein the bushing is configured to include a generally circumscribing ear and recess structure that will deflect in first, second and third directions in response to axial, conical and torsional forces applied to the bushing during operation. 
     
     
         6 . The bushing of  claim 1  wherein the ear structure increases the axial stiffness of the bushing while the recess substantially reduces the conical stiffness and the torsional stiffness of the bushing member. 
     
     
         7 . (canceled) 
     
     
         8 . The bushing of  claim 1  wherein the bushing includes a generally annular intermediate portion when loaded in compression has a radial section thickness less than or equal to about three millimeters. 
     
     
         9 . (canceled) 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . A bushing for use in a suspension of a vehicle comprising:
 a bushing having a passage, the bushing having plurality of annular reduced portions located in an exterior surface of the bushing for providing improved radial, torsional and conical.   
     
     
         13 . A method for manufacturing the bushing of  claim 1  for use in a suspension assembly in a vehicle, the method comprising the steps of:
 producing a bushing having a passage extending there through and plurality of annular reduced portions located in an exterior surface of the bushing. 
 
     
     
         14 . (canceled) 
     
     
         15 . (canceled) 
     
     
         16 . The method for manufacturing a bushing of  claim 13  wherein the step of producing the bushing member includes the steps of producing an inner member having a predefined shape, locating the inner member in a mold, molding an outer member on the inner member, the outer member including a plurality of extension members for improving the stiffness exhibited by the bushing member within the passage to exhibit a lower torsional and conical stiffness while exhibiting a higher radial and axial stiffness. 
     
     
         17 . (canceled) 
     
     
         18 . (canceled) 
     
     
         19 . The method of  claim 16  wherein the step of forming the inner member includes the step of forming the two end regions of the inner member to have a frusto-conical shape. 
     
     
         20 . The method for manufacturing a bushing of  claim 13  wherein the step of producing the bushing includes the step of molding an outer member from an elastomeric material selected from the group including a synthetic material, a rubber, a natural rubber material that is over-molded on an inner member. 
     
     
         21 . The bushing of  claim 1 , wherein the maximum thickness of the bushing is at the central regions of the outer member and inner member for interference fitting the central region of the outer member with a concave inner surface of a knuckle. 
     
     
         22 . The bushing of  claim 1 , wherein the first end region of the inner body has a frusto-conical shape. 
     
     
         23 . The bushing of  claim 1 , wherein the central region of the inner member has a rounded or substantially spherical shape. 
     
     
         24 . The bushing of  claim 1 , wherein
 the outer member is a molded rubber body; and   the bushing includes a generally annular intermediate portion when loaded in compression has a radial section thickness less than or equal to about three millimeters.   
     
     
         25 . The bushing of  claim 24 , wherein the outer member of the bushing is configured to include a generally circumscribing ear and recess structure that will deflect in first, second and third directions in response to axial, conical and torsional forces applied to the bushing during operation. 
     
     
         26 . The bushing of  claim 25 , wherein the ear structure increases the axial stiffness of the bushing while the recess substantially reduces the conical stiffness and the torsional stiffness of the bushing member. 
     
     
         27 . A knuckle and bushing assembly comprising a knuckle having an axial passage and the bushing of  claim 1 , wherein the axial passage of the bushing is aligned in the axial passage of the knuckle.