Semiconductor acceleration sensor including off axis acceleration cancellation

• US 5,212,986 A
• Filed: 07/03/1991
• Issued: 05/25/1993
• Est. Priority Date: 11/30/1990
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Takeuchi, Takenobu
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US07/725,473
• Time in Patent Office: 692 Days
• Field of Search: 73/517 R, 73/497, 73/862.67, 338/2, 338/5, 338/46
• US Class Current: 73/514.33
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges

Abstract

A semiconductor acceleration sensor has an acceleration sensor element on which gauge resistors are arranged so as to cancel sensed output component corresponding to any acceleration acting in a direction different from an acceleration to be sensed. Consequently, acceleration can be precisely sensed without being influenced by acceleration acting in different

Claims

1. A semiconductor acceleration sensor comprising:

a semiconductor acceleration sensor element having a longitudinal axis, said acceleration sensor for sensing acceleration in a particular direction perpendicular to the longitudinal axis, said semiconductor acceleration sensor element having a thin-walled portion including opposed first and second surfaces;

first piezoresistive sensing means disposed on the first surface of the thin-walled portion of said semiconductor acceleration sensor element changing in resistance in response to acceleration of said semiconductor acceleration sensor element, said first pieroresistive sensing means including first pierzoresistive elements for sensing acceleration of said semiconductor acceleration sensor element in the particular direction and second piezoresistive elements for sensing acceleration of said semiconductor acceleration sensor element in a direction perpendicular to the particular direction; and

second piezoresistive sensing means disposed on the second surface of the thin-walled portion of said semiconductor acceleration sensor element changing in resistance in response to acceleration of said semiconductor acceleration sensor element, said second piezoresistive sensing means including third piezoresistive elements for sensing acceleration of said semiconductor acceleration sensor element in the particular direction and fourth pierzoresistive elements for sensing acceleration of said semiconductor acceleration sensor element in a direction perpendicular to the particular direction, wherein said first, second, third, and fourth piezoresistive elements are interconnected in a bridge circuit for cancelling changes in resistance of said first and second piezoresistive sensing means in response to an acceleration acting on said semiconductor acceleration sensor element in a direction perpendicular to the particular direction.

2. The semiconductor acceleration sensor according to claim 1 wherein each of said piezoresistive element is a resistor.

3. The semiconductor acceleration sensor according to claim 2 wherein each of said gauge resistors of said first piezoresistive sensing means is orthogonal to one of said gauge resistors of said second piezoresistive sensing means.

4. The semiconductor acceleration sensor according to claim 3 wherein said first piezoresistive sensing means includes four gauge resistors, two of said gauge resistors of said first piezoresistive sensing means being orthogonal to two other gauge resistors of said first piezoresistive sensing means.

5. The semiconductor acceleration sensor according to claim 4 wherein said second piezoresistive sensing means includes four gauge resistors, two of said gauge resistors of said second piezoresistive sensing means being orthogonal to two other gauge resistors of said second piezoresistive sensing means.