Inertial force sensor

• US 8,966,976 B2
• Filed: 09/20/2013
• Issued: 03/03/2015
• Est. Priority Date: 01/24/2006
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Ohuchi, Satoshi, Aizawa, Hiroyuki, Terada, Jiro, Ishida, Takami, Satou, Ichirou, Ohkoshi, Hideo, Ashimori, Yohei
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US14/032,748
• Publication Number:
  US 20140026657A1
• Time in Patent Office: 529 Days
• Field of Search: 735/040.4, 735/041.2, 735/041.6
• US Class Current: 73/504.04
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5607 using vibrating tuning forks double-ended tuning forks using planar vibrating masses suspended at opposite ends G01C19/5719
• CPC Class Codes: G01C 19/5642 using vibrating bars or beams
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: G01P 15/097 by vibratory elements
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

An inertial force sensor includes a detecting device which detects an inertial force, the detecting device having a first orthogonal arm and a supporting portion, the first orthogonal arm having a first arm and a second arm fixed in a substantially orthogonal direction, and the supporting portion supporting the first arm. The second arm has a folding portion. In this configuration, there is provided a small inertial force sensor which realizes detection of a plurality of different inertial forces and detection of inertial forces of a plurality of detection axes.

Claims

1. An inertial force sensor comprising:

a detecting device which detects an inertial force applied in a direction parallel to a X-axis, a Y-axis, or a Z-axis, the X-axis, the Y-axis, and the Z-axis being orthogonal to each other

wherein the detecting device includes;

two first beams, and

two second beams each comprising a pair of beam portions extending from one of the first beams,

each end of the two second beams has at least one folding portion,

the two first beams are arranged on a substantially identical straight line,

a longitudinal direction of the two first beams are arranged in the Y-axis direction, and

a longitudinal direction of the two second beams are arranged in the X-axis direction,

wherein

each end of the two second beams are capable of being driven and oscillated in the X-axis direction, such that;

an angular velocity about the Z-axis is detected by detecting Coriolis Force corresponding to the driving and oscillation is caused in the Y-axis direction of the detecting device, and

an angular velocity about the Y-axis is detected by detecting Coriolis Force corresponding to the driving and oscillation is caused in the Z-axis direction of the detecting device.

2. The inertial force sensor according to claim 1, wherein

each end of the two second beams are driven and oscillated at the same phase.

3. The inertial force sensor according to claim 1, wherein

acceleration is detected by detecting distortion of the detecting device.

4. The inertial force sensor according to claim 1, wherein

the detecting device further includes a weight member formed at each end of the second beams.

5. The inertial force sensor according to claim 1, wherein

each end of the second beams are folded in meander shape.

6. The inertial force sensor according to claim 1, wherein

the detecting device further includes a connecting portion that connects a first end of each of the two first beams;

and

two fixing arms each of which is fixed to a second end the two first beams and fixed to a mounting substrate on which the detecting device is to be mounted.

7. The inertial force sensor according to claim 1, wherein

the detecting device further includes a connecting portion that connects a first end of each of the two first beams, and

the two fixing arms are each fixed to a second end of the two first beams.

8. The inertial force sensor according to claim 1, wherein

the detecting device further includes two fixing arms which are fixed to the two first beams and fixed to a mounting substrate on which the detecting device is mounted.

9. An inertial force sensor comprising:

a detecting device which detects an inertial force,

wherein the detecting device includes;

a supporting portion for fixing to a substrate,

two first beams extending in opposite directions from the supporting portion, and

two second beams each comprising a pair of beam portions extending from one of the first beams,

wherein

each beam portion of each pair of beam portions has at least two folding portions,

the two first beams are arranged on a substantially identical straight line, and

the pair of beam portions is arranged symmetric with respect to the substantially identical straight line.

10. The inertial force sensor according to claim 9, wherein

two first beams are extended to a first direction, and

each beam portion of each pair of beam portions has a first portion, a second portion, a third portion, and a fourth portion,

the first portion is extended to a second direction,

the second portion is extended from the first portion to the first direction,

the third portion is extended from the second portion to the second direction, and

the fourth portion is extended from the third portion to the first direction,

wherein the first direction and the second direction are orthogonal to each other.

11. The inertial force sensor according to claim 9, wherein

the detecting device further includes a weight member formed at each end of the second beams.

12. The inertial force sensor according to claim 10, wherein

each pair of beam portions has a fifth portion and a sixth portion,

the fifth portion is extended from the fourth portion to the second direction, and

the sixth portion is extended from the fifth portion to the first direction.

13. The inertial force sensor according to claim 10, wherein

a distance between the substantially identical straight line and the fourth portion is larger than a distance between the substantially identical straight line and the second portion.

14. The inertial force sensor according to claim 13, wherein

one of the two first beams is separate and spaced apart from another one of the two first beams.

15. The inertial force sensor according to claim 14, wherein said one of the two first beams is separate and spaced apart from said another one of the first beams by the supporting portion.

16. An inertial force sensor comprising:

a detecting device which detects an inertial force,

wherein the detecting device includes;

weight member having a first weight member, a second weight member, a third weight member and a fourth weight member;

a connecting member substantially surrounded by the first weight member, the second weight member, the third weight member and the fourth weight member;

a first arm connecting the first weight member and the connecting member;

a second arm connecting the second weight member and the connecting member;

a third arm connecting the third weight member and the connecting member; and

a fourth arm connecting the fourth weight member and the connecting member;

wherein an area of the connecting member is smaller than each of an area of the first weight member, an area of the second weight member, an area of the third weight member, and an area of the fourth weight member, and

wherein each of the first arm, the second arm, the third arm, and the fourth arm has at least two folding portions.

17. The inertial force sensor according to claim 16, wherein

each of the first weight member, the second weight member, the third weight member, and the fourth weight member is capable of being driven and oscillated in a plane, and move inward and outward simultaneously.

18. The inertial force sensor according to claim 16, wherein

each end of the two second beams are capable of being driven and oscillated in the X-axis direction,

an angular velocity about the Z-axis is detected by detecting Coriolis Force corresponding to the driving and oscillation is caused in the Y-axis direction of the detecting device, and

an angular velocity about the Y-axis is detected by detecting Coriolis Force corresponding to the driving and oscillation is caused in the Z-axis direction of the detecting device.

19. The inertial force sensor according to claim 16, wherein

each end of the first, second, third and fourth arms are driven and oscillated at the same phase.

20. The inertial force sensor according to claim 16, wherein

acceleration is detected by detecting distortion of the detecting device.

21. An inertial force sensor comprising:

a detecting device which detects an inertial force applied in a direction parallel to a X-axis, a Y-axis, or a Z-axis , the X-axis, the Y-axis, and the Z-axis being orthogonal to each other,

wherein the detecting device includes;

two first beams, and

two second beams each comprising a beam portion extending from one of the first beams,

wherein

the two second beams have at least two folding portions,

each end of the two second beams are capable of being driven and oscillated in the X-axis direction,

each of an angular velocity about the Z-axis and an angular velocity about the Y-axis is detected by detecting Coriolis Force corresponding to the driving and oscillation.

22. The inertial force sensor according to claim 21, wherein

the two second beams each comprising a pair of beam portions extending from one of the first beams.

23. The inertial force sensor according to claim 21, wherein

the two first beams are arranged on a substantially identical straight line.

24. The inertial force sensor according to claim 21, wherein

the two second beams each comprising a pair of beam portions extending from one of the first beams,

the two first beams are arranged on a substantially identical straight line, and

the pair of beam portions is arranged symmetric with respect to the identical straight line.

25. The inertial force sensor according to claim 21, wherein

the detecting device further includes a weight member formed at each end of the second beams.

26. An inertial force sensor comprising:

a detecting device which detects an inertial force, wherein

the detecting device includes;

two first beams,

two second beams each comprising beam portions extending from one of the first beams,

each of the two second beams has at least one folding portion,

wherein

each end of the two second beams are capable of being driven along a first direction,

two different directions of angular velocity are detected by detecting Coriolis force corresponding to the driving.

27. The inertial force sensor according to claim 26, wherein

the two first beams extend from in opposite directions from a supporting portion, and

the supporting portion is fixed to a substrate.

28. The inertial force sensor according to claim 27, wherein

the two second beams are symmetric relative to a substantially identical straight line.

29. The inertial force sensor according to claim 28, wherein

two first beams are extended to a first direction, and

each of the second beams has a first portion, a second portion, a third portion, and a fourth portion,

the first portion is extended to a second direction,

the second portion is extended from the first portion to the first direction,

the third portion is extended from the second portion to the second direction,

the fourth portion is extended from the third portion to the first direction.

30. The inertial force sensor according to claim 29, wherein

a distance between the substantially identical straight line and the fourth portion is larger than a distance between the substantially identical straight line and the second portion.

31. The inertial force sensor according to claim 30, wherein

one of the two first beams is separate and spaced apart from another one of the first beams.

32. The inertial force sensor according to claim 31, wherein said one of the two first beams is separate and spaced apart from said another one of the first beams by the supporting portion.