Vibrating gyroscope

• US 5,635,786 A
• Filed: 05/31/1995
• Issued: 06/03/1997
• Est. Priority Date: 06/03/1994
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Ishitoko, Nobuyuki, Fujimoto, Katsumi, Nakamura, Takeshi, Ebara, Kazuhiro
• Primary Examiner(s): BUDD, MARK OSBORNE
• Application Number:
  US08/455,717
• Time in Patent Office: 734 Days
• Field of Search: 310/316, 310/317, 310/319, 310/321, 310/329-332, 310/358, 310/366, 73/505
• US Class Current: 310/316.01
• CPC Class Codes: G01C 19/5642 using vibrating bars or beams

Abstract

A vibrating gyroscope 10 includes a regular quadrangular prism-shaped vibrator 12. The vibrator 12 includes, a first piezoelectric base plate 14a and a second piezoelectric base plate 14b, which are polarized reversely each other in a direction of thickness. On a main surface of the first piezoelectric base plate 14a, two divided electrodes 16, 16 are formed in laterally spaced relationship. On a main surface of the second piezoelectric base plate 14b, a common electrode 18 is formed. Between the first piezoelectric base plate 14a and the second piezoelectric base plate 14b, a dummy electrode 20 is formed. One output terminal of an oscillation circuit 30 as a driving means is connected to the two divided electrodes 16, 16 of the vibrator 12, via resistors 32a and 32b. Another output terminal of the oscillation circuit 30 is connected to the common electrode 18 of the vibrator 12. The two divided electrodes 16, 16 of the vibrator 12 are respectively connected to a non-inverting input terminal and an inverting input terminal of a differential amplifier circuit 36 as a detecting means, via resistors 34a and 34b.

Claims

1. A vibrating gyroscope comprising:

a first piezoelectric base plate polarized in a direction of thickness;

a second piezoelectric base plate laminated on said first piezoelectric base plate, and polarized in a reverse direction of the polarizing direction of said first piezoelectric base plate;

two divided electrodes formed on a main surface of said first piezoelectric base plate;

a common electrode formed on a main surface of said second piezoelectric base plate;

a driving means for applying a driving signal between said two divided electrodes and said common electrode; and

a detecting means for detecting a signal generated between said two divided electrodes.

2. A vibrating gyroscope according to claim 1, wherein

said driving means includes an oscillation circuit whose one output terminal is connected to said two divided electrodes, and another output terminal is connected to said common electrode, and

said detecting means includes a differential amplifier circuit whose two input terminals are respectively connected to said two divided electrodes.

3. A vibrating gyroscope comprising:

a first piezoelectric base plate polarized in a direction of thickness;

a second piezoelectric base plate laminated on said first piezoelectric base plate, and polarized in a reverse direction of the polarizing direction of said first piezoelectric base plate;

two divided electrodes formed between said first piezoelectric base plate and said second piezoelectric base plate;

a first common electrode formed on a main surface of said first piezoelectric base plate;

a second common electrode formed on a main surface of said second piezoelectric base plate;

a driving means for applying a driving signal between said first common electrode and said second common electrode; and

a detecting means for detecting a signal generated between said two divided electrodes.

4. A vibrating gyroscope according to claim 3, wherein

said driving means includes an oscillation circuit whose one output terminal is connected to said first common electrode, and another output terminal is connected to said second common electrode, and

said detecting means includes a differential amplifier circuit whose two input terminals are respectively connected to said two divided electrodes.

5. A vibrating gyroscope comprising:

a first piezoelectric base plate polarized in a direction of thickness;

a second piezoelectric base plate laminated on said first piezoelectric base plate, and polarized in the same direction as the polarizing direction of said first piezoelectric base plate;

two divided electrodes formed between said first piezoelectric base plate and said second piezoelectric base plate;

a first common electrode formed on a main surface of said first piezoelectric base plate;

a second common electrode formed on a main surface of said second piezoelectric base plate;

a driving means for applying a driving signal between said two divided electrodes, said first common electrode and said second common electrode; and

a detecting means for detecting a signal generated between said two divided electrodes.

6. A vibrating gyroscope according to claim 5, wherein

said driving means includes an oscillation circuit whose one output terminal is connected to said two divided electrodes, and another output terminal is connected to said first common electrode and said second common electrode;

and

said detecting means includes a differential amplifier circuit whose two input terminals are respectively connected to said two divided electrodes.

7. A vibrating gyroscope comprising:

a first piezoelectric base plate polarized in a direction of thickness;

a second piezoelectric base plate laminated on said first piezoelectric base plate, and polarized in the same direction as the polarizing direction of said first piezoelectric base plate;

two first divided electrodes formed on a main surface of said first piezoelectric base plate;

two second divided electrodes formed on a main surface of said second piezoelectric base plate;

a common electrode formed between said first piezoelectric base plate and said second piezoelectric base plate;

a driving means for applying a driving signal between one first divided electrode, one second divided electrode and said common electrode; and

a detecting means for detecting a signal generated between said one first divided electrode and said one second divided electrode;

wherein

the other first divided electrode and the other second divided electrode are connected each other.

8. A vibrating gyroscope according to claim 7, wherein

said driving means includes an oscillation circuit whose one output terminal is connected to said one first divided electrode and said one second divided electrode, and another output terminal is connected to said common electrode, and

said detecting means includes a differential amplifier circuit whose two input terminals are respectively connected to said one first divided electrode and said one second divided electrode.

9. A vibrating gyroscope comprising:

a first piezoelectric base plate polarized in a direction of thickness;

a second piezoelectric base plate laminated on said first piezoelectric base plate, and polarized in the same direction as the polarizing direction of said first piezoelectric base plate;

two first divided electrodes formed on a main surface of said first piezoelectric base plate;

two second divided electrodes formed on a main surface of said second piezoelectric base plate;

a common electrode formed between said first piezoelectric base plate and said second piezoelectric base plate;

a driving means for applying a driving signal between said two first divided electrodes, said two second divided electrodes and said common electrode; and

a detecting means for detecting a signal generated between one first divided electrode, one second divided electrode, the other first divided electrode and the other second divided electrode.

10. A vibrating gyroscope according to claim 9, wherein

said driving means includes an oscillation circuit whose one output terminal is connected to said two first divided electrodes and said two second divided electrodes, and another output terminal is connected to said common electrode, and

said detecting means includes a differential amplifier circuit whose one input terminal is connected to said one first divided electrode and said one second divided electrode, and another input terminal is connected to said other first divided electrode and said other second divided electrode.