GYRO SENSOR AND ELECTRONIC DEVICE INCLUDING THE SAME

• US 20130255377A1
• Filed: 03/22/2013
• Published: 10/03/2013
• Est. Priority Date: 04/03/2012
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: FURUHATA, Makoto, TANAKA, Satoru
• Granted Patent: US 8,899,112 B2
• Time in Patent Office: Days
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames

Abstract

A gyro sensor includes: a driving mass; a detection mass connected with the driving mass; a driving connection one end and the other end of which are connected with the driving mass and an anchor, respectively; an island connected with the anchor, and disposed with a clearance left between the island and the driving mass in such a manner as to be electrically connected with the driving mass; and a projection provided at least either on the surface of the driving mass opposed to the island, or on the surface of the island opposed to the driving mass. The driving unit includes a movable electrode unit connected with the driving mass, and a fixed electrode unit. The minimum distance between the driving mass and the island is longer than the driving amplitude of the driving mass and shorter than the maximum amplitude of the movable electrode unit.

Claims

1. A gyro sensor, comprising:

a driving mass driven in a first direction by a driving unit;

a detection mass connected with the driving mass;

a driving connection one end and the other end of which are connected with the driving mass and a first anchor, respectively;

a first island connected with the first anchor, and disposed with a clearance left between the first island and the driving mass in such a manner as to be electrically connected with the driving mass; and

a projection provided at least either on the surface of the driving mass opposed to the first island, or on the surface of the first island opposed to the driving mass,

wherein

the driving unit includes a movable electrode unit connected with the driving mass, and a fixed electrode unit disposed opposed to the movable electrode unit, and

the minimum distance between the driving mass and the first island is longer than the driving amplitude of the driving mass and shorter than the maximum amplitude of the movable electrode unit.

2. The gyro sensor according to claim 1, wherein

the first island has a first distance regulating portion extended to a position facing to the driving mass to regulate the distance between the driving mass and the first island;

and

the projection is provided at least either on the surface of the driving mass opposed to the first distance regulating portion, or on the surface of the first distance regulating portion opposed to the driving mass.

3. The gyro sensor according to claim 1, wherein

the two driving masses are arranged in the first direction;

and

the gyro sensor further includes

an intermediate connection which connects the two driving masses, the intermediate portion of the intermediate connection being fixed via a second anchor,

a second island disposed between the two driving masses and connected with the second anchor, and

projections provided at least either on the surfaces of the driving masses opposed to the second island or on the surfaces of the second island opposed to the driving masses.

4. The gyro sensor according to claim 3, wherein

the second island has a second distance regulating portion extended to positions facing to the respective driving masses to regulate the distances between the driving masses and the second island;

and

the projections are provided at least either on the surfaces of the driving masses opposed to the second distance regulating portion, or on the surfaces of the second distance regulating portion opposed to the driving masses.

5. The gyro sensor according to claim 1, wherein at least a pair of the first islands are arranged in a direction crossing the first direction.

6. The gyro sensor according to claim 1, wherein

the detection mass is connected with the driving mass via a detection connection;

and

a projection is provided at least either on the detection mass or on the detection connection.

7. The gyro sensor according to claim 1, wherein

the anchor is fixed to a substrate;

and

a projection is provided on the substrate at a position overlapping at least either with the driving mass or with the detection mass in the plan view.

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