Method for adjusting the temperature characteristic of a vibrating gyroscope

• US 6,089,087 A
• Filed: 09/30/1997
• Issued: 07/18/2000
• Est. Priority Date: 10/01/1996
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Fujimoto, Katsumi, Ishitoko, Nobuyuki
• Primary Examiner(s): Fuller, Benjamin R.
• Assistant Examiner(s): AW MUSSE, ABDULLAHI H
• Application Number:
  US08/940,229
• Time in Patent Office: 1,022 Days
• Field of Search: 73/504.12, 73/504.13, 73/504.02, 73/504.14-15, 73/504.08, 73/18, 73/503.3
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5663 Manufacturing; Trimming; Mounting; Housings

Abstract

A vibrating gyroscope includes a vibration member in which first and second piezoelectric substrates are joined together. On the outside main surface of the first piezoelectric substrate, a first external electrode divided into six electrode sections is formed. On the outside main surface of the second piezoelectric substrate, a second external electrode is formed. By removing a part of the electrode sections disposed at the center, a capacitance difference C(L)-C(R) between the capacitance C(L) formed between one of the electrode sections disposed at the center and the second external electrode, and the capacitance C(R) formed between another electrode section disposed at the center and the second external electrode is adjusted.

Claims

1. A method for adjusting a temperature characteristic of a vibrating gyroscope which includes a vibration member having opposing external electrodes formed on outside main surfaces of said vibration member, at least one of said external electrodes is divided, said method comprising the step of:

removing a part of at least one of said opposing external electrodes to adjust capacitances between said opposing external electrodes to adjust said temperature characteristic, wherein said divided electrode is divided into at least first and second sections and the capacitances are a first capacitance between the first section and the opposing external electrode and a second capacitance between the second section and the opposing external electrode, and said part of said at least one of said opposing external electrodes is removed such that the first and second capacitances are equal.

3. A method for adjusting a temperature characteristic of a vibrating gyroscope according to claim 1 or claim 2, wherein said part of said at least one of said opposing external electrodes is removed by laser trimming, etching, or grinding.

4. A method for adjusting a temperature characteristic of a vibrating gyroscope according to claim 1 or claim 2, wherein said vibration member comprises two piezoelectric substrates joined together, one of said opposing external electrodes being formed on an outer surface of one of said piezoelectric substrates and the other of said opposing external electrodes being formed on an outer surface of the other of said piezoelectric substrates.

5. A method for adjusting a temperature characteristic of a vibrating gyroscope according to claim 4, wherein said divided electrode is divided into a plurality of six sections, a first group of sections on one side of a longitudinal axis of said vibrating member and a second group of sections on an opposite side of said longitudinal axis, and said capacitances are a first capacitance between a center section of said first group of sections and said opposing external electrode and a second capacitance between a center section of said second group of sections and said opposing external electrode.

6. A method for adjusting a temperature characteristic of a vibrating gyroscope in accordance with claim 5, wherein said first and second groups each comprise three sections.

7. A method of adjusting a temperature characteristic of a vibrating gyroscope in accordance with claim 6, wherein said part of said at least one of said opposing external electrodes is removed from at least one of said center sections of said first and second groups of sections.

8. A method for adjusting a temperature characteristic of a vibrating gyroscope in accordance with claim 7, wherein said part of said at least one of said opposing external electrodes is removed by laser trimming, etching or grinding.

9. A method for adjusting a temperature characteristic of a vibrating gyroscope in accordance with claim 6, wherein said part of said at least one of said opposing external electrodes is removed such that said first and second capacitances are equal.

10. A method for adjusting a temperature characteristic of a vibrating gyroscope in accordance with claim 6, wherein said part of said at least one of said opposing external electrodes is removed such that said first and second capacitances are unequal.

2. A method for adjusting a temperature characteristic of a vibrating gyroscope which includes a vibration member having opposing external electrodes formed on outside main surfaces of said vibration member, at least one of said external electrodes is divided, said method comprising the step of:

removing a part of at least one of said opposing external electrodes to adjust capacitances between said opposing external electrodes to adjust said temperature characteristic, wherein said divided electrode is divided into at least first and second sections and the capacitances are a first capacitance between the first section and the opposing external electrode and a second capacitance between the second section and the opposing external electrode, and said part of said at least one of said opposing external electrodes is removed such that the first and second capacitances are unequal.

11. A method for adjusting a temperature characteristic of a vibrating gyroscope which includes a vibration member having opposing external electrodes formed on outside main surfaces of said vibration member, at least one of said external electrodes is divided, said method comprising the steps of:

measuring said temperature characteristic; and

removing a part of at least one of said opposing external electrodes to adjust capacitances between said opposing external electrodes to adjust said temperature characteristic.

12. A method for adjusting a temperature characteristic of a vibrating gyroscope according to claim 11, wherein said temperature characteristic is a change with temperature of a drift voltage of said vibrating gyroscope.

13. A method for adjusting a temperature characteristic of a vibrating gyroscope according to claim 12, wherein said capacitances are adjusted to reduce said change with temperature of said drift voltage.