GB953302A - Fluid damped shock absorbers - Google Patents

Abstract

953,302. Hydraulic-shock absorbers. BOULTON PAUL AIRCRAFT Ltd. Jan. 1, 1963 [Jan. 8, 1962], No. 706/62. Heading F2S. [Also in Division B7] A shock-absorber comprises an inner cylinder 23, a piston-rod 17 which is slidable within and projects from the cylinder and which has an integral piston 25, and at least two sets of orifices 34, 35 which are in, and spaced apart along, the cylinder wall and which place the cylinder chambers 32, 33 on either side of the piston 25 in communication with an annular chamber 24 which is formed between the cylinder 23 and an outer cylinder 22. The annular chamber 24 communicates, through orifices 47, 46, with a liquid reservoir space 42 and also, through apertures 28, 29 controlled by spring-loaded ball valves 30, 31 respectively, with the chambers 32, 33. The ball valves 30, 31 prevent flow of fluid from the chambers 32, 33 to the reservoir 42, the valve apertures 28, 29 being formed respectively in closure members 26, 27 for either end of the inner cylinder 23. One end of the outer cylindrical housing 22 is closed by a member 36 which is retained by a ring 37 and forms a bearing for the piston-rod 17 the other end, which extends beyond the inner cylinder, being closed by a plate 38 bolted at 39. The flange 41 of a stepped cylindrical member 40 is clamped between a shoulder 22a on the inner wall of the outer cylinder 22 and the closure member 27 to define the annular chamber of the reservoir 42. The latter, which accommodates a spring- loaded annular piston 43, communicates with the valve aperture 29 through an aperture 46 in the flange 41 and also, through further apertures 47, the annular space 24 and apertures 48, with the valve aperture 28. The piston 25 is provided with an orifice 25a, and the reservoir 42 can be recharged through a plug 49. The underside of the annular piston 43 is in communication with the hollow interior of the piston-rod 17 which is provided with a relief valve 51.