GB644945A - Shock absorber - Google Patents

Abstract

644,945. Hydraulic shock-absorbers. GABRIEL CO. May 7, 1948, No. 12600. Convention date, July 11, 1947. [Class 108(iii)] In an hydraulic shock absorber having a working cylinder 35 provided with a closure plug 15, and surrounded by a housing 16 in spaced relation to form a reservoir 36, a closure cap 14 for the housing 16, a space A between the cap 14 and the plug 15, the cap 14 having means forming communication between the reservoir 36 and the space A, packing means 37 carried by the cap 14, a passage through the plug 14 communicating with the interior of the cylinder 35 and with the space A, and a valve 41 located exteriorly of the plug and when seated closing the passage, a spring 40 is provided in the space A, acting on the packing 37 and on the valve 41. The passage through the plug comprises four ports 33, Fig. 5, which open into respective circumferential recesses 31 in the lower surface of the plug 15 (Fig. 6, not shown), and into a pair of arcuate recesses 29 in the upper surface of the plug. A raised edge 30 surrounding the recesses 29 forms a seating for the valve 41. Circumferentially-spaced legs 24 downwardly projecting from the cap 14 provide the communication between the space A and the reservoir 36 and are recessed at 25 to abut a shoulder 25 on the plug 15. The shock absorber piston has a reduced-diameter portion 50 having circumferentially-spaced axially-disposed grooves 60 which communicate with the interior 53 of the main piston portion 49 by means of ports 61 and a central port 56. Flow through the port 56 is controlled by a valve 69 the seating 58 of which is formed with a bleedchannel 59. A spring 70 loading the valve 69 is retained in a lower closure member. If the cylinder pressure exceeds a predetermined amount, the valve 41 lifts and liquid passes into the top of the reservoir 36. During its downward flow in the reservoir the liquid tends to cool the outer surface of the cylinder 35. If there is a replenishing valve and no orifice in the lower closure plug, the whole of the flow to the reservoir occurs through the valve 41. On rebound, the ring 64 closes the passage 52 and flow through the piston is controlled by the valve 69. Liquid flows back to the cylinder through the lower closure plug and if the cylinder pressure above the piston increases unduly, flow takes place again through the valve 41. The metal-tometal contact between the valve 41 and its seating, permits air to escape from the cylinder without lifting of the valve.