Vibrator

• US 5,117,148 A
• Filed: 10/31/1990
• Issued: 05/26/1992
• Est. Priority Date: 11/07/1989
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Fujimoto, Katsumi, Nakamura, Takeshi, Inoue, Jiro
• Primary Examiner(s): BUDD, MARK OSBORNE
• Application Number:
  US07/606,286
• Time in Patent Office: 573 Days
• Field of Search: 310/367-369, 310/366, 310/358, 310/359
• US Class Current: 310/367
• CPC Class Codes: B06B 1/0644 using a single piezoelectric element B06B1/0688 takes precedence
• CPC Class Codes: G01C 19/5663 Manufacturing; Trimming; Mounting; Housings
• CPC Class Codes: G01H 1/10 of torsional vibrations
• CPC Class Codes: H10N 30/2023 having polygonal or rectangular shape
• CPC Class Codes: H10N 30/2027 having cylindrical or annular shape

Abstract

The vibrator includes a columnar vibrating body consisting of a piezoelectric material. The vibrating body is formed into a polygonal or cylindrical column and, when necessary, a through hole is formed axially thereof. Furthermore, the vibrating body is polarized. On side faces of the vibrating body, at least three external electrodes are formed. Also, when the through hole is to be formed, an internal electrode is formed on its inner circumferential surface. By applying the driving signal to these electrodes, the vibrating body bends and vibrates. And, when the rotational angular velocity is applied to the vibrating body about its axis, a coriolis force is produced responsive thereto. By this coriolis force, the vibrating direction of the vibrating body changes, and a voltage is produced between the two external electrodes. By measuring the voltage, the rotational angular velocity applied to the vibrator can be measured.

Claims

1. A vibrator comprising:

a monolithic triangle columnar vibrating body made of a piezoelectric material; and

three external electrodes formed on three side faces of said vibrating body, wherein said vibrating body is polarized in a direction orthogonal to one of said three external electrodes.

2. A vibrator comprising:

a monolithic triangle columnar vibrating body made of a piezoelectric material;

three external electrodes formed on three side faces of said vibrating body;

a through hole formed and directed axially of said vibrating body; and

an internal electrode formed on an inner circumferential surface of said vibrating body, wherein said vibrating body is polarized in a direction from the inner circumferential surface to an outer peripheral surface.

3. A vibrator comprising:

a monolithic cylindrical vibrating body made of a piezoelectric material;

three external electrodes formed at regular intervals in an outer circumferential direction of said vibrating body;

a through hole formed on an inner circumferential surface of said vibrating body, wherein said vibrating body is polarized in a direction from the inner circumferential surface to an outer peripheral surface.

4. A vibrator comprising:

a triangle columnar vibrating body made of a piezoelectric material; and

three external electrodes formed on three side faces of said vibrating body, each of said three external electrodes being formed as an inter-digital electrode having a pair of comb-like electrodes arranged so as to inter-align with each other, one of the pair of comb-like electrodes of said inter-digital electrode being interconnected with a comb-like electrode form each of the inter-digital electrodes of other external electrodes, and said vibrating body being polarized between the comb-like electrodes of said three external inter-digital electrodes.