Desmodromic valve actuator

Claim 1

In a desmodromic valve actuator for an internal combustion engine having a cylinder head and a pair of parallel, enginedriven camshafts with coacting lobes, the combination of: A pair of parallel rocker arm sideplates, each of said rocker arm sideplates having a cylindrical bearing surface at each end and an intermediate cylindrical bearing surface, the centers of all three beariNg surfaces being parallel; A rocker support shaft fixed to said cylinder head and engaging the cylindrical bearing surfaces at one end of the rocker arm sideplates; A cam follower roller, said cam follower roller engaging the coacting camshaft lobes of said camshafts, said cam follower roller rotatably supported by a roller shaft, said roller shaft supported at its ends by said intermediate cylindrical bearing surfaces in said rocker arm sideplates; A trunnion yoke member having two journaled trunnions, a flat central yoke with two central yoke planar surfaces parallel to each other and to the journaled trunnions, and a central clearance hole through said central yoke planar surfaces, said journaled trunnions of said trunnion yoke member pivotally engaging said cylindrical bearing surfaces at the other ends of said rocker arm sideplates; A threaded valve stem extending through said central clearance hole in said flat central yoke; A pair of opposed stop-nuts threadably engaging said threaded valve stem on opposite sides of the trunnion yoke member, said stop-nuts slidably engaging said central yoke planar surfaces of the trunnion yoke member.