GB926836A - Improvements in or relating to sealing devices in semi-rotary fluid-pressure devices - Google Patents

Abstract

926,836. Oscillating vane hydraulic actuators and dampers. HOUDAILLE INDUSTRIES Inc. Nov. 17, 1961, No. 41271/61. Class 110 (2). Seals inserted in slots 31, 47 extending along fixed and oscillatory vanes 29 and 25, 25<SP>1</SP> respectively of a fluid pressure device 10, each comprise a spacer block 41, a resilient e.g. rubber 0-ring 40, 49 respectively and a non- metallic e.g. Nylonor " Teflon " (Registered Trade Mark) members 35, 46 respectively stiffer than the 0-ring, and check valved passages 43, 51 are respectively provided to pressurize the O- rings and maintain the members 35, 46 in sealing engagement with the shaft 13 and the wall 12 respectively. The vane 25<SP>1</SP> has on each side a passage 80 having a chamber 81 with a check valve 83 therein, which passages respectively open to working chambers 26, 27. The passages 80 register respectively with an inlet passage 84 or 87 when the vane is in one or other of its extreme positions and prevent locking of the vanes 25, 25<SP>1</SP> near the ends of their travel. The working chambers 26, 27 are interconnected in pairs by passages 28 and 32. Each fixed vane 29 is formed by two spaced parts retained by screws 30. Members 15, 20 forming seals and bearings for the piston shaft 17, and incorporating annular seals 56, 71 respectively, are retained by an end closure nut 19 and a nut 22 respectively. An 0-ring seal 60, supported by an annular seal 59 is pressurized through a check valved passage 61 in the member 15 from the working chamber 27, and an outer 0-ring seal 66 thereon, supported by an annular seal 67, is vented to the working chamber 26 through a check valved passage 69. The member 20 has a similar sealing arrangement to prevent external leakage along a portion 23 of the shaft 13.