GB376007A - Improvements in and relating to hydraulic shock absorbers - Google Patents

Abstract

376,007. Hydraulic shock-absorbers. JACKSON, L. MELLERSH-, 28, Southampton Buildings, London.-(American Chain Co., Inc.; 929, Connecticut Avenue, Bridgeport, Connecticut, U.S.A.) July 2, 1931, No. 19157. [Class 108 (iii).] In an hydraulic shock-absorber of the type in which vanes oscillate within a cylindrical casing, liquid flows through a passage of variable cross-sectional area in series with a second passage provided with a spring-controlled valve. In the constructions shown in Figs. 1 and 5, the operating shaft 6 carries a vane 33 which is pressed outwards by a spring 34 into engagement with a cylindrical sleeve 3 secured against rotation in the outer casing 1 by a projection 36 which also secures the abutment 35 against movement. When the vane 33 moves in an anticlockwise direction, liquid flows through a slot 37 in the abutment 35, a groove 38 in the operating shaft 6, a port 39 and a one-way valve 40 controlled by a spring 41, the rate of flow being dependent upon the overlap of the slot 37 and the groove 38 and also upon the resistance of the valve 40. When the vane moves in a clockwise direction, liquid flows similarly through the slot 44, the groove 38a, the port 45 and the valve 46 to the other side of the vane. With movement of greater amplitude, the grooves 38, 38a are covered and the liquid pressures rise abruptly. Liquid leaking from the working compartments passes through a slot 21 in the endplate 20 into the reservoir 26 from which it may be supplied through one-way valves 50, 52 to the working chambers. In a modification shown in Figs. 9 and 10, liquid flows through tapering grooves 61, 62 in the endplate 60 and thence through spring-controlled valves 63 to the other side of the vane, the effective area of flow through the groove 61 being thus dependent uponthe position of the vanes. Liquid may also flow through passages in the abutment, the flow being regulated by spring-controlled valves 67, 69 and by grooves 73, 74 in a screwed pin 72 adjustable externally of the apparatus. The cylindrical shell 78 is loose in the casing 57 and is free to yield slightly when the internal pressures are excessive thus acting as a safety valve. In the modification shown in Fig. 14 liquid flows, when the vane moves in the clockwise direction, through a port 96, a duct 93 and past the spring-controlled valve 95, the opening of the port 96 into the duct 93 being varied, according to the position of the operating shaft, by a ball 97 engaging a slot 91 in the shaft. A spring forces the ball on to the shaft. Movement of the vane in the opposite direction is controlled by a similar but independent series of valves and passages. A spring-controlled safety valve 98 is arranged axially in the operating shaft.