| 摘要 |
1,128,132. Ratchet clutches; differential gears. EATON YALE & TOWNS Inc. 23 March, 1967 [25 March, 1966], No. 13803/67. Headings F2C and F2D. A limited-slip bevel differential, Fig. 1 (not shown), is actuated by a jamming roller clutch incorporating a viscous shear coupling operating to ensure locking of the clutch at a predetermined value of slip irrespective of temperature. As shown the clutch rollers 66 are carried by a cage 65, a pair of opposite rollers 66a being urged into recesses 61 in the inner race 60 by springs engaging the cage 50 to normally hold the clutch free. The cage 50 is immersed in a viscous liquid and is made of a material having a high coefficient of thermal expansion in relation to the inner and outer races 60, 70 and has a flange portion 101 providing a shear film 103, the thickness of which varies with temperature to compensate for variation in viscosity of the liquid, so that the clutch engages at a substantially constant value of slip. In a modification, Fig. 4, the cage flange 101<SP>1</SP> is made of material of low thermal expansion and engages a stepped ring 111 of high thermal expansion and which, as the temperature rises, expands to frictionally engage the flange and provide an additional shear surface 113. |
