Servovalve
AssigneeHamilton Sundstrand Corporation
InventorZbigniew JASKIEWICZ
Life of this patent
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Abstract
A servovalve includes 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; wherein the drive assembly comprises a first fluid channel providing a flow path for fluid from the supply port to a first end of the spool and provided with a first flow control orifice. The assembly also includes a second fluid channel providing a rotating element provided with a cam profile located between the first flow control orifice and the second flow control orifice. The assembly also includes drive means arranged to rotate the rotating element.
Claims12
A servovalve comprising:
- a fluid transfer valve assembly comprising a supply port and a control port (PA, PB);
- 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;
- wherein the drive assembly comprises:
- a first fluid channel providing a flow path for fluid from the supply port to a first end of the spool and provided with a first flow control orifice;
- a second fluid channel providing a flow path for fluid from the supply port to a second end of the spool and provided with a second flow control orifice;
- a rotating element provided with a cam profile, located between the first flow control orifice and the second flow control orifice;
- and
- drive means arranged to rotate the rotating element to vary the rotational position of the cam profile with respect to the first and second flow control orifice, in response to the control signal, to control flow from the first and second flow control orifices and thus to control movement of the valve spool.
A method of driving a valve spool of a servovalve comprising:
- varying the fluid flow acting on respective ends of the valve spool via a fluid flow path by changing the size of respective first and second orifices of the flow path by means of a rotatable cam member between the orifices,
- wherein rotation of the cam member relative to the first and second orifices, in response to a control signal, varies the fluid flow from the respective orifice, which correspondingly varies the fluid flow to the respective ends of the valve spool.
Dependencies are inferred from the claim text.