GB785662A - Improvements in valve actuator assemblies for internal combustion engines - Google Patents

Abstract

785,662. Valve accessories. GENERAL MOTORS CORPORATION. Oct. 20, 1955 [Nov. 9, 1954], No. 30000/55. Class 135. An overhead poppet-valve for an internalcombustion engine operated by way of a tappet, push-rod and a rocker 3, Fig. 2, has a stem 7 around which is a U-section washer 11 forming a seat for one end of the valve spring 9 and having sufficient radial clearance 12 from the stem 7 to accommodate any lateral movement caused by the action of the rocker 3 and so prevent sticking of the stem during its axial motion. Seated on the washer 11 is a dished cap 16, which, when the valve is closed, has a small clearance 28 from the end face 17 of the stem 7. Removably located on the stem 7 is an abutment device comprising split wedges 18 and a tapered keeper 20, which secures the latter on the stem, this wedging engagement being assisted by tongues 21 on the wedges that are received in an annular groove 22 on the stem periphery; the lower end face 26 of the keeper 20 abuts the opposing surface 27 of the washer. In a modification, the abutment device consists of a C-shaped member sprung on to the stem groove, and the dished cap is replaced by a flat disc. In another modification the flat disc rests on a bush in the U-section washer, the other end of which bush abuts the inner part of the latter; the stem has the bottom of its groove relieved to enable the C-shaped member to be readily inserted and removed. In a final modification, the stem embodies a groove 322, Fig. 6, which serves to positively retain the keeper 120 against longitudinal movement; the valve clearance is provided between the cap 316 and the keeper 120, which clearance can be adjusted by screwing the cap more or less into the washer 311.