GB792932A - Improvements in or relating to flutter dampers - Google Patents

Abstract

792,932. Rotary dampers. HOUDAILLE INDUSTRIES, Inc. Jan. 9, 1956, No. 715/56. Class 108(3) A hydraulic damper for high frequency vibrations in which the opposed working chambers 32, 33, of the damper are connected together by a first fluid path which includes a first restrictor valve 95 in series with a passageway 90 which is of substantially length than a direct path between the chambers 32, 33, and by a second fluid path which includes a second restrictor valve which provides a constant leak between the chambers with variation of temperature. As shown, the passageway 90 is in the form of a coil of tubing, one end of which is connected by a passage 89, chamber 86 and passage 84 with the chambers 33, the other end being connected with the chambers 32 by a passage 85. The passages 84, and 85 are also connected by the valve 95, the setting of which may be adjusted at 99, and the adjustment of which is also thermostatically controlled by a bi-metallic element 105. The chambers 32 and 33 are defined by a rotary piston 15 having vanes 35, 35, disposed in a cylindrical chamber 18 which is formed with reaction members 34, 34. The latter are positioned relative to the cylinder by means of pins 51, and are prevented from being deflected by pressure of the liquid, by means of plugs 53. The chambers 32, 32, are connected by ports 62, 62, in the piston, and the chambers 33; 33, are connected by similar ports 63, 63. The ports 62 and 63 are connected within the piston by the valve 69, which is manually adjustable and thermostatically controlled in a similar manner to the valve 95. The valve 69 comprises a damping orifice formed by a chord-shaped slot 67 which operates in conjunction with a similarly shaped slot in a housing 65. The chambers 32, 33, are maintained with liquid by a reservoir 20 bounded by a spring loaded piston 21 and connected with the chambers 32, 33, by means of passages 30, 30. Specication 712,321 is referred to.