摘要 |
<p>Multi-mode friction clutch (20) having a plurality of interleaved clutch plates (24) for establishing gear ratios in planetary and countershaft automatic transmissions and to provide smooth and self-synchronized shifting without the use of one-way clutches. Gear thrust force from associated helical gearing (70) and opposing hydraulic pressure is used to regulate the hydraulic pressure of a piston chamber by shifting an annular control sleeve (34) which controls fluid exhaust from the chamber (36) to maintain a direct relationship between the torque capacity of the clutch and the variable torque it actually carries. Consequently, the clutch is automatically released when the torque diminishes to zero or reverses. The clutch is applied in a normal lock mode for predetermined gear ratios, set in one-way mode for shifting and totally released when the shift is completed.</p> |