GB408958A - Improvements in or relating to hydraulic shock absorbers for vehicles especially motor vehicles - Google Patents

Abstract

408,958. Hydraulic shock-absorbers. DEUTSCH, F. A., 27, Rankestrasse, Berlin. Oct. 14, 1932, No. 28753. Convention date, Oct. 14, 1931. [Class 108 (iii).] An hydraulic shock-absorber for vehicle s comprises a movable damping-member separating an operating-chamber and a refill chamber, or working in an operating-chamber communicating with a refill chamber, and a transfer passage between the chambers so proportioned or controlled that transfer of liquid from the refill chamber to the operating-chamber, to keep the operating-chamber filled with liquid, takes place during slow body oscillations but is so delayed or prevented during rapid wheel oscillations as to provide an inactive zone in the shock-absorber during such rapid oscillations. Fig. 1 shows a single-acting piston-and-cylinder shock-absorber wherein the piston 3 is reciprocated through links and levers by relative movement of the frame and axle. A narrow passage 5<a> and a passage 5 closed by a ball-valve 6 and interchangeable nozzle 7 are provided in the piston, while the refill chamber b above the piston is only partly filled with liquid. On upward movement of the piston during slow body oscillations the liquid passes from the chamber b through the passages 5, 5<a> and fills the space a beneath the piston so that on the following downward movement damping occurs. On upward movement of the piston during rapid wheel oscillations however there is not sufficient time for the liquid to pass through the piston and therefore on the following downward movement damping does not occur. Dimensions of one form of such a shock-absorber are given in the description. A double-acting rotary vane shock-absorber is shown in Fig. 2 wherein the refill chamber b is separated from the parts a<1>, a2 of the working chamber by a partition containing narrow passages y, z, and passages 5, 5<1> having non-return valves, the passage 5 being adjustable exteriorly by a member 8. On clockwise movement of the vane x liquid is forced from the part a2 through passage y into the chamber b thus damping the movement of the vane. If the movement is rapid there is no time for the liquid to pass through passages 5, z into part a<1>, so that there is no damping on the return movement of the vane. During the rapid return movement, however, liquid passes through the passages 51, y into the part a<2>, the passage 51 being sufficiently large to permit this so that on the subsequent rapid clockwise movement liquid is again forced through passage y thus damping the action. In a further construction of the double-piston type an inertia-controlled, spring-pressed, apertured valve 9, Fig. 3, closes the transfer passage 5 between the refill and operating-chambers b, a during rapid wheel oscillations, but remains open, due to the spring-pressure 10, during slow body oscillations. The shock-absorbing action is adjustable by throttling members 11, 12.