GB1392717A - Dampers - Google Patents

Abstract

1392717 Fluid dampers; Bowden mechanisms JOSEPH LUCAS (INDUSTRIES) Ltd 21 April 1972 [14 May 1971] 15034/71 Headings F2S and F2K A damper comprises an outer tubular flexible component 11 and an inner flexible component 12 extending within and movable relative to the outer component 11, a clearance between the components being filled with a viscous fluid 13 having a viscosity not less than 20,000 centistokes (e.g. a silicone liquid thickened with finely divided silica) which resists sudden relative movements of the components 11, 12 but permits gradual movements. The components are the inner core and outer sheath of a Bowden cable, which transmits movements of a first device 14 to a second device 15. A gradual movement of the device 14 is transmitted by the core 12 to the device 15, the viscous fluid acting as a lubricant for the relative movement of the core 12 and the sheath 11. Rapid movement of the device 14 is not trasmitted to the device 15, since the corresponding rapid movement of the core 12 is resisted by the viscous fluid 13, but is instead absorbed by a resilient coupling 16. If the altered position of the device 14 is maintained then the resilient coupling 16 exerts a force on the core 12, and so the core and the device 15 move gradually as permitted by the viscous liquid 13.