Patent GB-402337-A (GB)
Title: Improvements in or relating to shock absorbers
IPC: F16F9/504
Filed: 1933-05-03
Abstract: 402,337. Hydraulic shock-absorbers. DELCO PRODUCTS CORPORATION, 329, East 1st Street, Dayton, Ohio, U.S.A.- (Assignees of Rossman, E. F. ; 1845, Emerson Avenue, and Kindl, C. H.; 159, Lonsdale Avenue, both in Dayton, Ohio, U.S.A.) May 3, 1933, No. 12922. Convention date, Jan. 16, 1933. [Class 108 (iii).] In a vehicle hydraulic shock-absorber comprising a cylinder 27, Fig. 3, in which a doubleended piston 40 is reciprocated by vehicle spring vibrations, in addition to an intake valve 54 or 70 and a pressure release valve 58 or 71 in each end of the piston which permit restricted flow of fluid through the piston to and from a central reservoir 26, a sleeve-valve 96, Fig. 2, secured to and governed by a spring-pressed inertia-controlled mass 100, is provided in a chamber 80 connected with one end 51 of the cylinder through passages 91, 82, 85 and increases the resistance of the shock-absorber on vertical acceleration of the vehicle body. The description is limited to means for increasing the shock absorber resistance on upward acceleration only of the vehicle body. During small separating movements of the body and axle the piston 41, Fig. 3, moves to the right and (a) liquid from the reservoir 26 lifts the valve 54 and flows to the chamber 50 while (b) liquid under pressure in the chamber 51 lifts the spring-pressed valve 87, which is less heavily loaded than the valve 71 which therefore remains closed, and passes to the chamber 80 through passages 82, 91, apertures 93 and an annular groove 92 in a plug 90, and a sidepassage 97 in the sleeve-valve 96. If, however, there is sufficiently great upward acceleration of the vehicle body the plug 90 moves upwards relative to the sleeve-valve 96 which substantially closes the apertures 93, and the pressure of the liquid in the chamber 51 opens the valve 71 and the liquid flows to the reservoir 26. Downward movement of the plug 90 relative to the sleeve-valve on downward movement of the vehicle body is prevented by a strong spring 106 acting on the mass 100. The maximum resistance of the shock-absorber is maintained during the whole upward accelerated movement of the vehicle body as the liquid passing through the passages 93 in the plug 90 encounters a greater resistance when passing through the part of the groove 92 diametrically opposite the side-passage 97 than when passing through the passage 97 itself and this greater pressure on one side of the valve causes it to " stick in the open position. In a modification, however, the passage 97 is replaced by an annular groove and the sleeve valve being thus " balanced " is gradually closed by its return spring as the acceleration of the vehicle body diminishes. The piston 40, Fig. 3, is in two parts 41, 42 pressed together by springs 45, 46 acting on bolts 43, 44 screwed into the parts 41, 42. The valve 54 is pressed on an annular ridge 53 by a spring 55 bearing at its other end against a ring 56 fixed in a groove in the passage 52 while the valve 58 which has a sharp edge 59 is pressed against the inner surface of the valve 54 by a spring 62 stronger than the spring 55 and acting between the valve 54 and an abutment 61 on the end of the valve-stem 57.