| 摘要 |
1,211,072. Torsional vibration dampers. POWDER COUPLINGS Ltd. 9 Oct., 1967 [7 Oct., 1966], No. 44984/66. Heading F2S. A torsional vibration damper for a rotary shaft consists of a circular section housing 4 and which is capable of free rotation with respect to a member 8 which is mounted within the housing for rotation relative thereto about the housing axis. The housing also contains particulate solid material such as metal shot 9 which constitutes friction coupling means between the member 8 and housing 4 so that when the member 8 is driven by a shaft 2 the housing 4 rotates with it. The frictional coupling torque varies with rotational speed in consequence of the dependence of closeness of packing of the shot on centrifugal force. If, at a particular speed of rotation, the housing and member 8 are rotating together there is no tendency for the shot particles to rub against each other, but a change in rotational speed of the driven member will disturb this equilibrium and cause energy to be dissipated by friction between the shot particles. Thus torsional oscillations of the driving shaft will be frictionally damped. An outer cover 11, Fig. 2 (not shown), may be secured to the hub 1 of the member 8 and surround and enclose the housing 4. |
