Patent GB-495763-A (GB)
Title: Valves
IPC: F16F9/28
Filed: 1937-04-15
Abstract: 495,763. Fluid-actuated valves. LESLIE, I. A. April 15, 1937, No. 10819. [Class 135] [Also in Group XXXII] In a hydraulic shock-absorber in which now between the compression chambers is controlled by a spring-loaded valve, more particularly described in Specification 432,725, having a member slidable on its stem, the valve being opened by direct pressure when flow is in one direction and by pressure on the slidable member when flow is in the other direction, the end of the stem further from the valve seat moves in a liquid filled chamber in communication with one of the compression chambers or the passages connecting them and constituting with the chamber or passages a closed system whose capacity is not increased or increased materially by operation of the valve. In one form, Fig. 1, the valve E is fitted with a slidable member in the form of a flanged sleeve F<3>, F' and controls flow between the chambers A<1>, A<2> of a shock-absorber having pistons B, B<1> oscillated by a shaft B<3> and lever B<2>. The valve stem is provided with a hole G<1> forming a communication between the chamber A and a chamber in which the end of the valve stem moves. The chamber also houses the valve spring F provided with a seating F<2> integral with a rod G<2> adapted to be moved by a cam G<3> on the shaft B<3> to increase the valve loading at the end of the stroke. The rod is hydraulically held in a depressed position by means more particularly described in Specification 440,405, [Group XXXII]. In another form, Fig. 2, the valve E, F<3> controls flow between one chamber H and a conduit H<2> leading to the other chamber of a shock-absorber of the double-ended piston type. In this construction, the valve stem is solid and the chamber H<3> in which the end of the valve stem moves is connected to the chamber H by a conduit H<4>. The seating F<2> may be moved hydraulically to increase the valve loading. As shown in Fig. 3, the seating F<2> is fixed to a rod H<5> having an enlargement H<12> slidable in a guide H<13>. The end of the rod H<5> is rigid with the end H<6> of a metal bellows H' housed in a chamber H<8> to which oil under pressure can be admitted through a pipe H<9>. The space H<11> between the enlargement H<12> and the end of the guide H<13> is connected to the chamber H<3> by a passage H<10> and has a X-sectional area equal to that of the rod H<5>. The space H<14> between the rod H<5> and guide H<13> is vented to the interior of the bellows which is vented to the atmosphere by a passage H<16>. In a further form, Fig. 6, in which the valve loading is varied hydraulically, passages N', N<2> lead to the compression chambers and the valve P, O<3> seats in a member O held in position by a member O<1> screwed into a member O<2> in turn screwed into the shockabsorber casing N. The sleeve O<3> is adapted to bear against a metal pressing P<2> fitting over the end of the valve stem and the stem and pressings are drilled at P<1>, P<3> to connect the passage N<1> with the chamber formed by the interior of the member O<1>. The valve spring R<3> acts on the valve through a seating R<2> and a rod R. The other end of the spring bears against a member R<4> forming the end of a metal bellows R<7> housed in a chamber R<5> to which oil under pressure can be admitted by a pipe S. The interior of the bellows is vented to the atmosphere by passages R<8>, N<3>. Two other forms are described in which the spring has a fixed seating ina screwed plug which may be removed to allow the spring and valve to be removed as a unit. In one of these forms, Fig. 5, the chamber H' is connected to a compression chamber A<1> both by a hole G<1> through the valve stem and a passage K<1>. The sleeve is replaced by a member K having a seating K <4>. When the valve is lifted by pressure on the member K, fluid will flow to the chamber A<1> through both the hole K<2> and the passage K<1>.