One-directional piston-tube electrostatic microactuator
OwnerFaez BA-TIS, Ridha BEN-MRADinventors
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Abstract
A MEMS electrostatic piston-tube actuator is disclosed. The actuator comprises two structures. A structure that comprises a plurality of fixed piston-like electrodes that are attached to a base, and form the stator of the actuator. A second structure that comprises a plurality of moving tube-like electrodes that are attached to the body of the upper structure and form the rotor of the actuator. The rotor is attached to the stator through a mechanical spring. The rotor of the actuator provides a translational motion, about the normal axis to the structures. The present piston-tube actuator utilizes a configuration that enables the use of wide area electrodes, and therefore, provides a high output force enabling translation of the rotor.
Claims14
A micro electromechanical system (MEMS) electrostatic actuator, comprising:
- a. a first stator plate having an x- and y-axis defining an x-y plane, and a z-direction being perpendicular to the x-y plane, said stator plate having a top surface parallel to the x-y plane, and a thickness along the z-direction, a stator-support-frame surrounding the stator plate;
- an array of spaced apart piston electrodes extending from the top surface along said z-direction of the stator plate, said pistons having vertical piston-walls and a piston-height;
- said pistons being electrically connected to each other and electrically addressable;
- b. a rotor plate having a non-moving rotor-support-frame surrounding the rotor plate, wherein said rotor-support-frame is placed on and attached to said stator-support-frame;
- c. an array of spaced apart tubes being open on both ends fabricated in the rotor plate, each said tube having a vertical tube-wall and a tube-height, wherein said tubes being aligned with said pistons, and wherein each said tube having a tube opening sized and shaped to receive and interdigitate with each said piston without the piston-walls touching the tube-walls, said tubes being electrically connected to each other but electrically isolated from the pistons;
- d. a plurality of springs connecting said array of tubes to said non-moving rotor-support-frame, wherein during an actuation in response to electrostatic forces from a drive voltage applied between said arrays of pistons and said rotor plate, the rotor translates along the z-direction, and
- e. an actuator-plate attached to said rotor plate and surrounded by said tubes, wherein said actuator plate forms a single rigid body with said tubes,
- whereby said actuator provides a one dimensional translational motion along the z-direction.
Dependencies are inferred from the claim text.