| 摘要 |
<p>1,200,690. Vehicle driving gear. EATON YALE & TOWNE Inc. 6 Nov., 1968 [30 Nov., 1967], No. 62684/68. Heading B7H. [Also in Division F2] In a vehicle transmission including, in the drive line of optionally driving front wheels, a double-acting one-way jamming roller clutch normally held out of engagement but automatically engaged upon a predetermined speed differential arising between the driving and driven members, e.g. when the main driving wheels slip, to give a four-wheel drive, a viscous shear fluid coupling 140 is mounted in parallel to the one-way clutch so that, when the drive line is disconnected from the prime mover for twowheel drive, the front wheels may drive the free shaft 37 through the coupling 140 without cyclic engagement/disengagement of the clutch, thus reducing the noise and wear. The coupling 140 comprises a disc (142), Fig. 6 (not shown), fast with a driven shaft 42 and extending into a narrow recess (143) in a flange 50 fast with shaft 37 and filled with silicone liquid. Although the transmitted torque is small, it is sufficient to rotate the free shaft 37, and hence prevent engagement of the clutch. As shown, the clutch comprises rollers 92 acting between an outer race 64 on the flange 50 and an inner polygonal member 76 on the shaft 42. The shaft 37 is driven by an engine (12), Fig. 1 (not shown), through a known transfer box (18), as is a shaft (21) driving the rear wheels. The rollers 92 are mounted on a cage 91 normally held by a spring arrangement 110 to prevent engagement of the clutch, the cage being moved to engage the clutch in the event of the predetermined speed differential arising. The cage has an end flange 101 extending into a recess 103 filled with the silicone liquid, the viscous shear drag of which at the predetermined speed differential overrides the spring arrangement 110 to move the cage to engage the clutch. The spring arrangement comprises four springs (115), (116), Fig. 5 (not shown), abutting seats (113), (114) on a member (111) fast with the shaft 42 and a member (112) fast with the cage 91. Again, Figs. 7 and 8 (not shown), the spring arrangement comprises a blade spring (151) riveted to the cage and having fingers (161) engaging in notches in a thrust washer (152) fast with shaft 42, relative rotation betweenthe cage and washer being opposed by the fingers which are cammed from the notches.</p> |
