GYRO SENSOR, ELECTRONIC APPARATUS, AND MOVING OBJECT

• US 20140245831A1
• Filed: 02/25/2014
• Published: 09/04/2014
• Est. Priority Date: 03/04/2013
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: FURUHATA, Makoto
• Granted Patent: US 9,857,174 B2
• Time in Patent Office: Days
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion

Abstract

A gyro sensor includes a vibrating body, a first spring structure portion that extends in a direction along a first axis and is connected to the vibrating body, first and second vibrating portions that are disposed in parallel to each other in the direction along the first axis and are excited and vibrated in an opposite phase to each other, and a second spring structure portion that extends in the direction along the first axis and is connected to the first and second vibrating portions, in which a first spring constant K₁ of the first spring structure portion is smaller than a second spring constant K₂ from a middle point at which a length between both ends of the second spring structure portion is equally divided into two to one end of the second spring structure portion.

Claims

1. A gyro sensor comprising:

a vibrating body;

a first spring structure portion that extends in a direction along a first axis and is connected to the vibrating body;

first and second vibrating portions that are disposed in parallel to each other in the direction along the first axis and are excited and vibrated in an opposite phase to each other; and

a second spring structure portion that extends in the direction along the first axis and is connected to the first and second vibrating portions,

wherein a first spring constant K₁ of the first spring structure portion is smaller than a second spring constant K₂ from a middle point at which a length between both ends of the second spring structure portion is equally divided into two to one end of the second spring structure portion.

2. The gyro sensor according to claim 1,

wherein the length between both ends of the first spring structure portion is larger than a length from one end of the second spring structure portion to the middle point.

3. The gyro sensor according to claim 1,

wherein a width of the first spring structure portion is smaller than a width of the second spring structure portion.

4. The gyro sensor according to claim 1,

wherein the first spring structure portion and the second spring structure portion extend in the direction along the first axis while reciprocating in a direction along a second axis perpendicular to the first axis, and

wherein a length of the first spring structure portion in the direction along the second axis is larger than a length of the second spring structure portion in the direction along the second axis.

5. The gyro sensor according to claim 4,

wherein the number of times of extension of the first spring structure portion in the direction along the second axis is larger than a half of the number of times of extension of the second spring structure portion in the direction along the second axis.

6. The gyro sensor according to claim 1, further comprising:

an excitation portion that excites the vibrating body; and

a detection portion that is provided in the vibrating body.

7. The gyro sensor according to claim 1,

wherein a ratio γ

(K₂/K₁), which is a ratio of the second spring constant K₂ to the first spring constant K₁, is 2 or more and 4096 or less.

8. An electronic apparatus comprising the gyro sensor according to claim 1.

9. A moving object comprising the gyro sensor according to claim 1.