Patent classifications
F15B2211/424
Actuator with end stop valve
Actuator systems and methods of operation are disclosed. The systems include a hydraulic actuator having a primary piston having a piston head arranged within a housing defining retract and extend chambers on opposite sides of the piston head. A control element is configured to control a supply of pressure to each of the retract and extend chambers. An actuator valve is coupled to the housing and includes a secondary piston that is biased into the retract chamber in an open flow state and when the primary piston is in a fully retracted state the piston head urges the secondary piston into a closed flow state. The actuator valve defines a flow chamber where, in an open flow state, fluid can be passed through the flow chamber and in a closed flow state the fluid is prevented from passing through the flow chamber.
HYDRAULIC ACTUATOR WITH MECHANICAL PISTON POSITION FEEDBACK
A hydraulic actuator for a downhole pump system includes a piston housing having a head end and a base end. A drive piston is movable within the piston housing between a first piston position proximate to the head end and a second piston position proximate to the base end. The hydraulic actuator includes a control valve that translates between a first control valve position in which fluid is directed into the base end and a second control valve position in which fluid is directed into the head. When the piston moves to the first piston position, a mechanical positon feedback system translates the control valve from the first control valve position to the second control valve position. When the piston moves to the second piston position, the mechanical positon feedback system translates the control valve from the second control valve position to the first control valve position.