| 摘要 |
<p>In a continually variable belt-driven transmission, a system for actuating and controlling the operation of the forward clutch (118) and reverse clutch (120) includes a source of hydraulic pressure (36) regulated at line pressure, an accumulator control valve (228), a line and belt load control solenoid (242) and solenoid-actuated valve (240), an accumulator (230), a decel disconnect solenoid-operated valve (370) and a manual valve (220). The line and belt-load control valve (240) regulates a pressure signal applied to the accumulator control valve (228) whose output pressure develops, on the piston (236) of the accumulator (230), a force that adds to a spring force tending to purge the accumulator (230) and add that flow to the flow through an orifice (234) directed through the manual valve (220) to the selected clutch (118;120). The decel disconnect solenoid (378) operates in accordance with a control signal that senses the occurrence of a hard wheel brake condition to vent the forward clutch (118), thereby permitting the pulleys (14,16) of the transmission to turn during the braking condition sufficient to allow a drive ratio change to the lowest drive ratio, and thereafter to regulate clutch pressure to permit immediate reacceleration of the vehicle.</p> |
