Slider pad for roller finger follower

Abstract

A roller finger follower is provided having a housing and two separate outer arms mounted at one end to a pivot axle that extends through the housing. A roller is mounted in the housing The outer arms extend longitudinally along sides of the housing and include high lift cam contact surfaces. The outer arms having an outer arm body and separately formed longitudinal body, retained on the outer arm body, the longitudinal body including the cam contact surface. The longitudinal body is formed of a high durability material or coated with a suitable coating, the outer arm body formed of a lower grade, lower cost material.

What is claimed is: 
     
         1 . A roller finger follower for a valve train of an internal combustion engine, comprising:
 a primary lever having a slot in which a roller is mounted by a transverse axle;   a secondary lever that extends along at least one longitudinal side of the primary lever that is mounted for pivoting movement at one end of the primary lever by a pivot axle;   the secondary lever including:
 a body, having a depression along a substantial portion of an upper longitudinal periphery of the lever; 
 a longitudinal body shaped to fit into the depression and retained on the body; 
 the longitudinal body having a high lift cam contact surface located at an upper periphery adjacent to the roller; and 
   a coupling arrangement located between the primary lever and the secondary lever which in a locked position, locks the secondary lever to the primary lever at least in an activation direction of a valve, and in an unlocked position, allows the secondary lever to pivot relative to the primary lever.   
     
     
         2 . The roller finger follower of  claim 1 , wherein the longitudinal body is made of bearing grade steel, such as SAE 52100. 
     
     
         3 . The roller finger follower of  claim 2 , wherein the secondary lever body is made of a tool steel. 
     
     
         4 . The roller finger follower of  claim 1 , wherein the secondary lever body includes a slot at an upper periphery adjacent the depression shaped to accept a retention piece connected to the longitudinal body, the retention piece retaining the longitudinal body to the secondary lever body at least in a radial direction. 
     
     
         5 . The roller finger follower of  claim 4 , wherein the longitudinal body is additionally retained to the secondary lever body by one of press fitting, staking or laser welding. 
     
     
         6 . The roller finger follower of  claim 4 , wherein the retention piece is a rectangular prism connected at an upper periphery to the lower periphery of the longitudinal body with a radially extending post. 
     
     
         7 . The roller finger follower of  claim 6 , wherein the retention piece is substantially shorter in length than the longitudinal body. 
     
     
         8 . The roller finger follower of  claim 1 , wherein the longitudinal body is made of a coatable material and coated at least at the cam contact surface with amorphous hydrocarbon. 
     
     
         9 . The roller finger follower of  claim 8 , wherein the amorphous hydrocarbon includes at least one of metal free amorphous hydrocarbon or metal-free amorphous hydrocarbon with sp 2  and sp 3  hybridized carbon. 
     
     
         10 . The roller finger follower of  claim 1 , wherein the cam contact surface of the longitudinal body is coincident with an upper radial periphery of the secondary lever body, adjacent the depression. 
     
     
         11 . The roller finger follower of  claim 1 , wherein the secondary lever comprises two separate outer arms. 
     
     
         12 . An outer arm for a three arm switchable roller finger follower for a valve train of an internal combustion engine, comprising:
 an outer arm body, having a depression along a substantial portion of an upper longitudinal periphery of the arm and a pivot recess to accept a pivot axle;   a longitudinal body shaped to fit into the depression and retained on the outer arm body; and   the longitudinal body having a high lift cam contact surface located at an upper periphery.   
     
     
         13 . The outer arm of  claim 12 , wherein the longitudinal body is made of bearing grade steel, such as SAE 52100. 
     
     
         14 . The outer arm of  claim 13 , wherein the outer arm body is made of a lower grade steel, such as tool steel. 
     
     
         15 . The outer arm of  claim 12 , wherein the outer arm body includes a slot at an upper periphery adjacent the depression shaped to accept a retention piece connected to the longitudinal body, the retention piece retaining the longitudinal body to the outer arm body at least in a radial direction. 
     
     
         16 . The outer arm of  claim 15 , wherein the longitudinal body is additionally retained to the outer arm body by one of press fitting, staking or laser welding. 
     
     
         17 . The outer arm of  claim 15 , wherein the retention piece is a rectangular prism connected at an upper periphery to the lower periphery of the longitudinal body with a radially extending post. 
     
     
         18 . The outer arm of  claim 17 , wherein the retention piece is substantially shorter in length than the longitudinal body. 
     
     
         19 . The outer arm of  claim 12 , wherein the longitudinal body is made of a coatable material and coated at least at the cam contact surface with amorphous hydrocarbon. 
     
     
         20 . The outer arm of  claim 19 , wherein the amorphous hydrocarbon includes at least one of metal free amorphous hydrocarbon or metal-free amorphous hydrocarbon with sp 2  and sp 3  hybridized carbon.