| 摘要 |
<p>A power transmission has a continuously variable gear ratio, the torque being transmitted by friction between balls (16, 17) and runways (14, 15, 18, 19, 29, 31, 36, 38). The balls and runways are divided into two groups, each group comprising a set of balls (e.g. 16) which roll on four runways (e.g. 14, 18, 36, 38), two of the runways (36, 38) being stationary or intercoupled to rotate with the same angular velocity, and the other two runways (14, 18) being coupled to the driving and the driven shaft respectively. The two groups are coupled in parallel, each transmitting torque from the driving shaft to the driven shaft.
<??>At least two runways in each group are axially displaceable to vary the gear ratio. The cross-sectional shapes of the runways are designed in accordance with certain criteria in order to ensure that contact between all the balls and runways is maintained during this displacement. </p> |
