Rocker arm

Abstract

A rocker arm for a type III valve train assembly for an internal combustion engine includes: a roller follower for following a cam in use; a roller axle about which the roller follower rotates in use; a biasing means holder, the biasing means holder being connected to the roller axle for sliding movement relative to the roller axle over a fixed distance, the biasing means holder contacting a reaction component in use; and a biasing means arranged to bias the biasing means holder away from the roller axle. The rocker arm is arranged such that, in use, sliding movement of the biasing means holder relative to the roller axle when the biasing means holder contacts the reaction component when a lift profile of the cam engages the roller follower causes the biasing means to compress and thereby to urge the roller follower into contact with the cam.

1 . A rocker arm for a type III valve train assembly for an internal combustion engine, the rocker arm comprising:
 a roller follower configured to follow a cam in use;   a roller axle about which the roller follower is configured to rotate in use;   a biasing means holder, the biasing means holder being connected to the roller axle for sliding movement relative to the roller axle over a fixed distance, the biasing means holder being configured to contact a reaction component in use; and   a biasing means arranged to bias the biasing means holder away from the roller axle,   wherein the rocker arm is configured such that, in use, sliding movement of the biasing means holder relative to the roller axle when the biasing means holder contacts the reaction component when a lift profile of the cam engages the roller follower causes the biasing means to compress and thereby to urge the roller follower into contact with the cam.   
     
     
         2 . The rocker arm according to  claim 1 , wherein the biasing means holder defines at least one slot in which the roller axle is slidably disposed. 
     
     
         3 . A valve train assembly of an internal combustion engine, the valve train assembly comprising:
 the rocker arm according to  claim 1 ;   the reaction component; and   the cam,   wherein the valve train assembly is configured such that, in use, when the roller follower engages a base circle of the cam, there is a lash between the reaction component and the biasing means holder, and when a lift profile of the cam engages the roller follower, the biasing means holder contacts the reaction component to move the biasing means holder relative to the roller axle to compress the biasing means thereby to urge the roller follower into contact with the cam.