| 摘要 |
<p>An engine compression braking system (10) for a multicylinder engine having a plurality of hydraulically operated exhaust valve actuators (44, 46, 48, 50), one for each respective cylinder exhaust valve. A hydraulically operated braking control valve (14) is operatively coupled to each of the exhaust valve actuators (44, 46, 48, 50) to in turn simultaneously open each associated exhaust valve. Selective fluid coupling and decoupling of hydraulic operating lines to the braking control valve (14) enables a spool valve element (56) to effectively float between an operating end point and a return end point to prevent the spool valve element (56) from undesirably impacting the end point stops. The engine braking horsepower can be varied by timing the simultaneous opening of the exhaust valves and the duration of the opening.</p> |
