| 主权项 |
1. A valve actuation system, comprising:
a valve moveable between a first position to prevent a flow of fluid and a second position to allow a flow of fluid; a cam assembly configured to move the valve between the first position and the second position, wherein the cam assembly is mechanically connected to the valve; a fluid actuator configured to selectively prevent the valve from moving to the first position, and further configured to selectively hold the valve at a position between the first position and the second position; a source of fluid in fluid communication with the fluid actuator; a bi-directional control valve configured to control a flow of fluid between the source of fluid and the fluid actuator; a fluid passageway connecting the bi-directional control valve with the fluid actuator; an accumulator in fluid communication with the fluid passageway; a restrictive orifice disposed between the accumulator and the fluid passageway to restrict a flow of fluid between the accumulator and the fluid passageway; and a relief valve in fluid communication with the fluid passageway and moveable between a closed position to prevent a flow of fluid therethrough to create a high pressure circuit in the valve actuation system and an open position to allow a flow of fluid therethrough to create a low pressure circuit in the valve actuation system, wherein the relief valve is actuated between the closed position and the open position based at least on a pressure in the fluid passageway, wherein the high pressure circuit allows the fluid to pass through the fluid passageway to actuate the fluid actuator, and wherein the low pressure circuit allows at least a portion of the fluid in the fluid passageway to drain from the fluid passageway to an external environment. |
