A servovalve includes: a fluid transfer valve assembly comprising a supply port and a control port; a moveable valve spool arranged to regulate flow of fluid from the supply port to the control port in response to a control signal; and a drive assembly configured to axially move the valve spool relative to the fluid transfer assembly in response to the control signal to regulate the fluid flow. The drive assembly comprises a piezoelectric actuator configured to vary the flow of fluid to respective ends of the valve spool in response to the control signal.

A piezoelectric linear actuator includes a laminated piezoelectric actuator, a lower support member that supports the laminated piezoelectric actuator, a pressing member that biases the laminated piezoelectric actuator from the top thereof, a guide member connected to the lower support member to guide the pressing member; and a displacement transmission member which includes a pair of displacement transmission plates, an adjustment screw connected to the pair of displacement transmission plates, an output section connected to the pair of displacement transmission plates, and an elastic body that biases the output section downward.

In accordance with at least one aspect of this disclosure, a flow control device can include, a first plate having one or more windows defining a flow path therethrough, a second plate configured to abut the first plate, and an actuator operatively connected to one or more of the first plate and/or the second plate. The actuator can be configured to drive the first plate and/or the second plate relative to one another to enlarge or reduce the flow path through the one or more windows in the first plate.

A valve assembly that provides reliable opening and closing valves at specified times despite changing performance characteristics of the valve is disclosed. The valve assembly includes a controllable valve selectively actuatable to control flow of a fluid therethrough, with the controllable valve having a variable valve open/close response time. The valve assembly also includes a plurality of sensors configured to measure current operational parameters of the controllable valve and/or the fluid and a valve controller programmed to process valve timing control instructions generated by an external source, process inputs from the plurality of sensors regarding the measured operational parameters of the controllable valve and/or the fluid, and provide an actuation signal to the controllable valve based on the valve timing control instructions and the inputs from the plurality of sensors, so as to control a timing of an actuation of the controllable valve.

An actuator unit for a fuel injection valve of a vehicle internal combustion engine. The actuator unit includes an electronic component formed as a stack. The component includes a plurality of electrode layers and a plurality of material layers which are arranged alternately and react to the application of an electric field. The component also has two outer electrodes electrically connected to respective electrode layers on at least one circumferential side of the component. Additionally, the actuator unit has a piezoelectric sensor coupled to the component in a force-fitting manner, in the stroke direction of the component. When the component is in operation, the sensor detects a force generated by the component, as a voltage or charge between two electrodes arranged on opposing end faces, of a sensor element. The electrodes are deposited from an electrically conductive material directly onto at least the end faces of the sensor element.

A slide valve comprises a bushing in which fluid openings are provided which extend through the wall of the bushing, a slide which is arranged adjustably in the bushing and is provided with at least one fluid duct, and an electroactive polymer actuator which can adjust the slide in the bushing.

The disclosure relates to a piezo actuator device, preferably for controlling a dispensing of an application agent onto a component, including: at least one movable valve body for opening and closing at least one valve seat, at least one preferably pivotable actuating arm for actuating the at least one valve body, and a piezo actuator configured to move the at least one valve body to close and/or open the at least one valve seat.