Physical quantity sensor, electronic apparatus, and moving body

Patent metadata

Field	Value
Publication number	US-9746490-B2
Application number	US-201514817324-A
Country	US
Kind code	B2
Filing date	Aug 4, 2015
Priority date	Aug 13, 2014
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A physical quantity sensor includes: a base substrate; a movable portion; a plurality of movable electrode fingers which are provided in the movable portion; a fixed electrode finger which is provided on the base substrate; and a fixing portion which fixes the movable portion to the base substrate. In the movable electrode fingers, a movable electrode finger which opposes the fixing portion in the first direction is included. A clearance between the movable electrode finger and the fixing portion is smaller than a clearance between the movable electrode finger and the fixed electrode finger. The width of the movable electrode finger is greater than the width of other movable electrode finger.

First claim

What is claimed is:

1. A physical quantity sensor comprising:
a base substrate;
a movable portion which is displaceable in a first direction with respect to the base substrate;
a plurality of movable electrode fingers which are provided on the movable portion and disposed along the first direction, the plurality of movable electrode fingers including a first movable electrode finger and a second movable electrode finger;
a fixed electrode finger which is provided on the base substrate, and disposed to oppose the first movable electrode finger in the first direction; and
a fixing portion which fixes the movable portion to the base substrate and is displaceable in the first direction,
wherein the second movable electrode finger opposes the fixing portion in the first direction,
wherein a clearance between the second movable electrode finger and the fixing portion in the first direction is smaller than a clearance between the first movable electrode finger and the fixed electrode finger in the first direction, and
wherein a width of the second movable electrode finger is greater than a width of other movable electrode fingers.

2. The physical quantity sensor according to claim 1 ,
wherein a part of the fixing portion in the first direction defines a pair of protections that extend toward the second movable electrode finger.

3. The physical quantity sensor according to claim 1 ,
wherein a width of each of the plurality of movable electrode fingers decreases as a distance from the fixing portion increases.

4. The physical quantity sensor according to claim 1 ,
wherein one pair of fixing portions are provided to oppose each other in the first direction via the movable portion, and
wherein the movable portion is fixed to the one pair of fixing portions in both end portions in the first direction.

5. The physical quantity sensor according to claim 4 ,
wherein the second movable finger is located at a terminal end of the movable portion.

6. The physical quantity sensor according to claim 1 ,
wherein a width of the fixed electrode finger is smaller than the width of the first movable electrode finger.

7. The physical quantity sensor according to claim 1 ,
wherein a part of the fixing portion defines a pair of projections that extend toward the second movable electrode in a longitudinal direction of the fixing portion.

8. An electronic apparatus comprising:
the physical quantity sensor according to claim 1 .

9. An electronic apparatus comprising:
the physical quantity sensor according to claim 2 .

10. An electronic apparatus comprising:
the physical quantity sensor according to claim 3 .

11. An electronic apparatus comprising:
the physical quantity sensor according to claim 4 .

12. An electronic apparatus comprising:
the physical quantity sensor according to claim 5 .

13. An electronic apparatus comprising:
the physical quantity sensor according to claim 6 .

14. An electronic apparatus comprising:
the physical quantity sensor according to claim 7 .

15. A moving body comprising:
the physical quantity sensor according to claim 1 .

16. A moving body comprising:
the physical quantity sensor according to claim 2 .

17. A moving body comprising:
the physical quantity sensor according to claim 3 .

18. A moving body comprising:
the physical quantity sensor according to claim 4 .

19. A moving body comprising:
the physical quantity sensor according to claim 5 .

20. A moving body comprising:
the physical quantity sensor according to claim 6 .

Assignees

• Seiko Epson Corp

Inventors

• Tanaka Satoru

Classifications

• B81B3/0013

  Structures dimensioned for mechanical prevention of stiction, e.g. spring with increased stiffness · CPC title

• G01P15/125 Primary

  by capacitive pick-up · CPC title

• B81B2201/0235

  Accelerometers · CPC title

• B81C2203/0109

  Bonding an individual cap on the substrate · CPC title

• G01C19/5719

  using planar vibrating masses driven in a translation vibration along an axis · CPC title