| 摘要 |
<p>A CVT transmission has two pulleys 16,18 with V section grooves 22, which can vary the radius at which a belt 20 engages the grooves 22, to vary the drive ratio. Sensors 30,32,34 may provide details about engine, wheel or pulley speeds. A clutch 28 is automatically controlled to transmit a torque Mk directed from an engine 10, which is a predetermined amount in excess of the engine torque Mm. If engine torque Mm increases rapidly, clutch 28 will slip whilst the torque Mk transmitted by the clutch 28 catches up with Mm, thereby causing a damping effect of shocks in the drive line. The torque Mk is controlled by applying an appropriate thrust to the clutch plates, and will also depend on, eg, the frictional coefficient. A control system is used to compare values gained by the sensors 30,32,34 with ideal values, and the applied thrust is varied accordingly.</p> |
