摘要 |
A control for a continuously variable unit (CVU) provides control pressures to the variable sheave portions of the CVU pulleys. A first of the pulleys has a direct control pressure and the second of the pulleys has a control pressure proportional to the direct control pressure. The proportional pressure is established by a pair of control valves. One of the control valves issues a bias pressure, proportional to the commanded ratio in the CVU, to the other of the control valves. The other control valve communicates a sheave control pressure, proportional to or equal to the bias pressure, to the second pulley to control the relative position of the variable sheave.
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