GB664491A - Improvements relating to fluid pressure relieving apparatus - Google Patents

Abstract

664,491. Fluid-actuated. valves. CLOUDSLEY, J. L. Jan. 5, 1948 [Dec. 6, 1946], No. 36222/46, Class 135 [Also in Group XXXII] In fluid pressure relieving apparatus of the kind in which fluid is enabled to pass relatively freely from one chamber to another through a port or passage but is restricted in passing in the opposite direction, the restricted flow takes place between the inner periphery of a dished resilient annular disc of the Belleville washer type, or a member moving therewith, and a co-operating circular valve seating surface. The invention is especially applicable to shock absorbers and Fig. 1 shows the piston 11 of a hydraulic shock absorber containing a recuperating valve formed as an aperture disc 8 urged against a seat 10 by Belleville washers 9, the upper of which forms a valve closure at 9a against an apertured plate 8a. The aperture in the disc 8 is of such size as to limit the downward displacement of the upper washer from the plate 8a. Fig. 2 shows a further assembly for a hydraulic shock absorber comprising a piston 11 with an apertured end plate 12 and an apertured plug 15. The plug 15 guides a slidable flanged part 18 which in turn guides a recuperating valve 24 and a pair of Belleville washers 22, 22t. The valve face 20 of the part 18 seats against a valve seat member 21 guided in peripherally slotted ring 28 resting on a screwed ring 26 with notches 27. The seat member 21 guides a further pair of Belleville washers 32, 32<SP>1</SP> held in place by a cap screw 36. A plate spring 47 loads the whole assembly of the seat member 21 against the valve part 18. The space between the washers 22, 22<SP>1</SP> has access to the interior of the part 18 through an aperture 39, whilst the space between the washers 32, 321 acts as a dashpot and is connected with the interior of the part 18 through the spring-loaded check valve 42. Liquid also escapes from the latter space through a helical groove 45 and a groove 46 formed in the bottom of the ring 28 or alternatively through the groove 45 and a port 46<SP>1</SP>. In this form, the movement of the valve face 20 away from the seat 21 is hydraulically limited by an interchangeable end plate 481 threaded on a boss 48 or where the end plate is integral with the boss by a separate loose ring 48x. Specification 526,945 is referred to.