Hybrid motor

• US 6,093,995 A
• Filed: 01/25/1999
• Issued: 07/25/2000
• Est. Priority Date: 09/09/1993
• Status: Expired due to Term

• Current Assignee: Cymer Incorporated (ASML Holding NV)
• Original Assignee: Active Control eXperts, Inc. (ASML Holding NV)
• Inventors: Lazarus, Kenneth B., Saarmaa, Erik, Crawley, Edward F., Russo, Farla M.
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US09/237,154
• Time in Patent Office: 547 Days
• Field of Search: 310/328, 310/324, 310/330, 310/331
• US Class Current: 310/328
• CPC Class Codes: H02N 2/043 Mechanical transmission means, e.g. for stroke amplification

Abstract

A hybrid actuator includes strain actuated elements that displace fluid to move a piston, with the elements forming a fluid housing, and being oriented and actuated to optimize force, stroke or bandwidth. In one preferred embodiment the elements are cylinders enclosing the fluid, with radial and axial components of strain-induced dimensional change adding together to enhance displacement. In another preferred embodiment, piezo bender elements produce large stroke, high bandwidth movements. Strokes of up to fifty percent of actuator length, and bandwidths above 500 Hz are achieved in light weight electrically actuated devices free of external piping or hydraulics. The actuator is readily integrated into a gate valve, sub-woofer, or other driven device.

Claims

1. A hybrid actuator comprising:

a housing defining a fluid reservoir;

an electrical actuator member within said housing, said member having a major movable displacing face for displacing fluid in the reservoir and forming a bounding wall of the reservoir, said fluid filling the reservoir; and

a piston slidably extending into the reservoir such that motion of the piston tracks displacement of fluid within the reservoir, displacement of fluid being caused by motion of said displacing face,

wherein said hybrid actuator produces a measurable stroke when said electrical actuator member is electrically actuated,

wherein said piston includes means for enhancing the stroke of said hybrid actuator, and

wherein said piston extends through two opposed ends of said housing and is of different diameters at each said end.

2. A hybrid actuator according to claim 1, wherein a portion of said piston within said housing, is tapered.