GB735636A - Improvements in or relating to rotary valve mechanisms for engines or machines having pistons reciprocating in cylinders - Google Patents

Abstract

735,636. Engine distributing valves. TACCONI, G. Dec. 28, 1951, No. 30348/51. Class 122 (2). [Also in Groups XXVII and XXVIII] A rotary conical valve 12, Fig. 1, axially slidable on its actuating shaft 6, is urged towards its seat by a spring 14 and driven by a collar 8 splined on the shaft 6 and carrying rollers 11 engaging V-shaped notches in the valve, whereby the valve is moved off its seat slightly if it tends to seize, and the valve is balanced against the axial and radial thrusts produced on it by the pressure in the cylinder by means of a fluid pressure which varies with the pressure in the cylinder. In Fig. 1 the cylinder pressure is transmitted through a passage 27 to an annular chamber 26 to urge the valve towards its seat and balance the axial thrust thereon and to a chamber 28 to balance the valve against the radial thrust due to cylinder pressure. Lubricating oil supplied under pressure to a chamber 31 flows through passages 30, 32, 33 in the valve shaft 6 to spiral grooves 34, 35 and thence to passages 36, 37 to the valve surfaces. In a modification, Fig. 5, the lubricating oil supply pipe 63 is connected during periods of low pressure in the cylinder 44 by passages 65, 66 in the valve actuating shaft to an annular chamber 53, which chamber is connected during periods of high cylinder pressure by passages 65, 61, 60 to a spring-loaded piston 70 open to cylinder pressure. The high pressure in the cylinder 44 is then transmitted by the piston 70 and the lubricating oil in passages 60, 61 and 66 to the chamber 53 to urge the valve towards its seat and balance the axial thrust. The radial thrust is balanced by transmitting the cylinder pressure through a passage 75 in the valve to a chamber 74. The piston 70 may be replaced by a diaphragm.