Cam follower apparatus

Abstract

Provided is a cam follower apparatus that has excellent durability, assembly characteristics and freedom of design, and together with being able to reduce the size and weight, is able to reduce the manufacturing cost. Both end sections of a support shaft 3 a are inserted into support holes 15 b , 15 c in support wall sections 12 b, 12 c, and the support shaft 3 a is supported by the support wall sections 12 b, 12 c such that relative rotation is possible. An inner ring 16, having an outer diameter D 16 that is greater then the inner diameter d 15 of the support holes 15 b, 15 c, is fitted around the outer circumferential surface of the middle section in the axial direction of the support shaft 9 a so as to be able to rotate together with the support shaft 9 a . Moreover, a plurality of cylindrical rollers 13 are arranged between an inner-ring raceway 17, which is formed around the outer circumferential surface of the inner ring 16, and an outer-ring raceway 18, which is formed around the inner circumferential surface of a tappet roller 8 b that is provided on the outer-diameter side of the inner ring, so as to be able to roll freely.

What is claimed is: 
     
         1 . A cam follower apparatus, comprising:
 a rocker arm that has a pair of support wall sections that are provided so as to be separated from each other by a space, and a pair of support holes that are formed in positions in these support wall sections that are aligned with each other, and is provided so as to face a cam that is fastened to a camshaft that rotates in synchronization with the crankshaft of an engine and oscillates and displaces according to the motion of this cam;   a support shaft that, with both ends sections thereof inserted in the pair of support holes, spans between the pair of support wall sections and is supported by the support wall sections;   an inner ring member that has an outer diameter that is larger than the inner diameter of the support holes, and fits with an interference fit onto the middle section in the axial direction of the support shaft in a state such that relative rotation with respect to the support shaft is prevented; and   a tappet roller that is arranged around the inner ring member so as to be able to rotate relative to the inner ring member.   
     
     
         2 . The cam follower apparatus according to  claim 1 , wherein both end sections of the support shaft fit with a loose fit into the pair of support holes so as to be able to rotate on the inside of the support holes. 
     
     
         3 . The cam follower apparatus according to  claim 1 , wherein a radial roller bearing is provided between the inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring member. 
     
     
         4 . The cam follower apparatus according to  claim 3 , wherein the radial roller bearing is a full complement roller bearing. 
     
     
         5 . The cam follower apparatus according to  claim 4 , wherein a pair of circular ring shaped washers are provided on the inside in the width direction of the pair of support wall sections so as to cover the opening sections on both ends of a bearing space of the radial roller bearing, and have an outer diameter that is greater than the dimension in the height direction of the support wall sections. 
     
     
         6 . The cam follower apparatus according to  claim 1 , wherein the inner circumferential surface of the tappet roller comes in sliding contact with the outer circumferential surface of the inner ring member. 
     
     
         7 . The cam follower apparatus according to  claim 1 , wherein a cylindrical shaped member is located between the inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring member so as to be able to rotate relative to the tappet roller and the inner ring member.