| 摘要 |
<p>A vacuum actuator (25) is actuated by the vacuum in the pneumatic circuit of the load system (15). A throttle (19) is controlled so that when the vacuum is below a given value the actuator opens the or air valve. In the case of a petrol engine this increases the speed. - For a Diesel engine the actuator ensures that the valve throttles the air flow to create a vacuum in the supply system. This assists the vacuum pump to exhaust air from the load system. The actuator returns the engine to its normal operating state once the load system vacuum has reached the preset value.</p> |
