Electrostatic drive device and circuit for controlling same

• US 5,124,879 A
• Filed: 06/13/1990
• Issued: 06/23/1992
• Est. Priority Date: 07/12/1989
• Status: Expired due to Fees

• Current Assignee: Omron Corporation
• Original Assignee: Omron Corporation
• Inventors: Goto, Hiroshi
• Primary Examiner(s): Williams, Howard L.
• Assistant Examiner(s): ELMS, RICHARD T
• Application Number:
  US07/537,140
• Time in Patent Office: 741 Days
• Field of Search: 361/234, 361/233, 269/8, 269/903, 340/870.3, 340/870.37, 310/309, 310/12, 318/116, 318/135
• US Class Current: 361/233
• CPC Class Codes: H01L 21/682 Mask-wafer alignment in general G03F7/70, G03F9/70
• CPC Class Codes: H02N 1/008 Laterally driven motors, e.g. of the comb-drive type

Abstract

An electrostatic drive device includes at least one fixed electrode plate provided on a fixed portion, and at least one movable electrode plate provided on a movable portion resiliently supported on the fixed portion so as to move freely. The fixed electrode plate and movable electrode plate are disposed as to oppose each other in parallel relation, and the movable portion is driven by an electrostatic force produced by applying a voltage across the fixed electrode plate and the movable electrode plate.

Claims

1. An electrostatic drive device comprising:

a fixed portion;

at least one fixed electrode plate provided on said fixed portion;

a movable portion resiliently supported to said fixed portion so as to move freely;

at least one movable electrode plate provided on said movable portion, said movable electrode plate having first and second opposing sides, said movable electrode plate being attached to said movable portion at said first side and facing a respective said fixed electrode in a parallel relationship at said second side each of said movable and respective fixed electrode plates forming a pair of electrode plates; and

,

means for applying a voltage across said pair of electrode plates to produce electrostatic forces which drive said movable portion.

2. A control circuit for controlling the drive of an electrostatic drive device which includes at least one fixed electrode plate provided on a fixed portion of said drive device, and at least one movable electrode plate provided on a movable portion of said drive device, said movable portion being resiliently supported to the fixed portion so as to move freely, the fixed electrode plate and movable electrode plate being so disposed as to oppose each other in parallel relation, and the movable portion being driven by an electrostatic force produced by applying a voltage across the fixed electrode plate and the movable electrode plate, said control circuit comprising:

displacement command means for outputting a command signal which sets an amount of displacement of the movable electrode plate with respect to the fixed electrode plate; and

converting means responsive to said command signal for providing said voltage across said fixed electrode plate and said movable electrode plate, said converting means operating on the command signal from said displacement command to linearize the amount of displacement of the movable portion based on said command signal.