GB1162999A - An Improvement in or relating to Vehicle Shock Absorbers - Google Patents

Abstract

1,162,999. Self-levelling shock absorber unit. STAHLWERKE BRUNINGHAUS G.m.b.H. 18 Nov., 1966 [19 Nov., 1965], No. 51869/66. Heading F2S. A vehicle shock absorber includes a piston 3 slidable in a cylinder 4 and having a first passage 9 closable by a first non-return valve 10, a second passage 11 closable by a second non-return valve 12, the valves 10, 12 being operable in opposite directions of movement of the piston 3, an equalizing chamber 5 partly filled with oil and communicating with one end 7 of the cylinder 4 by way of a port 17 closable by a non-return valve 18, a transfer port 6 between the equalizing chamber and the cylinder 4 in a position in which it is normally closed by the piston when the vehicle on which the shock absorber is fitted is at rest, and a gas-filled absorption chamber 15 arranged to balance the pressure of oil in the other end of the cylinder, said second non-return valve 12 acting as a safety valve operable by an excessive load on the shock absorber to connect the opposite ends of the cylinder. The end 7 of the cylinder 4 also communicates with the equalizing chamber by means of a small diameter port 19. When the piston 3 oscillates above the port 6 it acts as a pump to transfer liquid from the equalizing chamber 5 past one-way valves 18, 10 and into the upper end 7a of the cylinder 4 which communicates, through a port 13, with the liquid compartment of the absorption chamber 15 which includes a separating diaphragm 14. In a modification, Fig. 2 (not shown), the absorption chamber (15) is located at the upper end, axially, of the shock-absorber and includes a bellows separating member (16). In both embodiments when the piston descends to reveal the port 6, (6) liquid flows from the upper portion 7a of the cylinder into the equalizing chamber 5. Reference has been directed by the Comptroller to Specification 869,132.