Angular velocity sensor

• US 20100050767A1
• Filed: 09/01/2009
• Published: 03/04/2010
• Est. Priority Date: 09/02/2008
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Higuchi, Hirofumi, Inoue, Masaki, Fujii, Tetsuo
• Granted Patent: US 8,234,920 B2
• Time in Patent Office: Days
• US Class Current: 73/504.120
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis

Abstract

An angular velocity sensor includes first and second oscillators and a coupling beam. The coupling beam couples the first and second oscillators together in such a manner that the first and second oscillators vibrate relative to each other in a predetermined direction. The coupling beam includes a first post portion joined to a surface of the first oscillator, a second post portion joined to a surface of the second oscillator, and a spring portion that joins the first post portion to the second post portion. The spring portion is spaced from the first and second oscillators and has elasticity in the predetermined direction.

Claims

1. An angular velocity sensor comprising:

a first sensor unit including a first drive member configured to be driven in a first direction, a first detection member configured to move in a second direction perpendicular to the first direction, and a first elastic member configured to join the first drive member to the first detection member;

a second sensor unit including a second drive member configured to driven in the first direction, a second detection member configured to move in the second direction, and a second elastic member configured to join the second drive member to the second detection member; and

a first coupling beam joined to front surfaces of the first and second drive members to couple the first and second drive members together, wherein

the first coupling beam is spaced from front surfaces of the first and second detection members.

2. The angular velocity sensor of claim 1, wherein

the first coupling beam is joined to the front surface of the first drive member at a position corresponding to a center of gravity of the first drive member, and

the first coupling beam is joined to the front surface of the second drive member at a position corresponding to a center of gravity of the second drive member.

3. The angular velocity sensor of claim 1, further comprising:

a second coupling beam joined to back surfaces, opposite to the front surfaces, of the first and second drive members to couple the first and second drive members together.

4. The angular velocity sensor of claim 1, further comprising:

a spring member joined to the first coupling beam, wherein

a junction between the first coupling beam and the first drive member, a junction between the first coupling beam and the second drive member, and a junction between the first coupling beam and the spring member are located on a straight line.

5. The angular velocity sensor of claim 4, wherein

the first coupling beam, the first drive member, the second drive member, and the spring member are electrically connected together.

6. The angular velocity sensor of claim 1, wherein

the first coupling beam has elasticity in the first direction.

7. The angular velocity sensor of claim 1, wherein

the first coupling beam has a perpendicular portion that is perpendicular to the first direction.

8. The angular velocity sensor of claim 1, further comprising:

a third coupling beam configured to couple the first and second detection members together.

9. The angular velocity sensor of claim 1, wherein

the first coupling beam has an acute portion that forms an acute angle with respect to the first direction.

10. An angular velocity sensor comprising:

a first sensor unit including a first drive member configured to be driven in a first direction, a first detection member configured to move in a second direction perpendicular to the first direction, and a first elastic member configured to join the first drive member to the first detection member;

a second sensor unit including a second drive-member configured to driven in the first direction, a second detection member configured to move in the second direction, and a second elastic member configured to join the second drive member to the second detection member; and

a first coupling beam joined to front surfaces of the first and second detection members to couple the first and second detection members together, wherein

the first coupling beam is spaced from front surfaces of the first and second drive members.

11. The angular velocity sensor of claim 10, wherein

the first coupling beam is joined to the front surface of the first detection member at a position corresponding to a center of gravity of the first detection member, and

the first coupling beam is joined to the front surface of the second detection member at a position corresponding to a center of gravity of the second detection member.

12. The angular velocity sensor of claim 10, further comprising:

a second coupling beam joined to back surfaces, opposite to the front surfaces, of the first and second detection members to couple the first and second detection members together.

13. The angular velocity sensor of claim 10, further comprising:

a spring member joined to the first coupling beam, wherein

a junction between the first coupling beam and the first drive member, a junction between the first coupling beam and the second drive member, and a junction between the first coupling beam and the spring member are located on a straight line.

14. The angular velocity sensor of claim 13, wherein

the first coupling beam, the first detection member, the second detection member, and the spring member are electrically connected together.

15. The angular velocity sensor of claim 10, wherein

the first coupling beam has elasticity in the second direction.

16. The angular velocity sensor of claim 10, wherein

the first coupling beam has a perpendicular portion that is perpendicular to the second direction.

17. The angular velocity sensor of claim 10, further comprising:

a third coupling beam configured to couple the first and second drive members together.

18. The angular velocity sensor of claim 10, wherein

the first coupling beam has an acute portion that forms an acute angle with respect to the second direction.

19. The angular velocity sensor of claim 10, wherein

the first and second sensor units are located on a plane parallel to a plane defined by the first and second directions.

20. The angular velocity sensor of claim 10, wherein

the first and second sensor units are made of silicon, metal, resin, glass, ceramic, or a mixture of at least two of these materials.

21. The angular velocity sensor of claim 10, further comprising:

a first layer where the first and second sensor units are formed, and

a second layer where the first coupling beam is formed, the second layer located to face the first layer to define a space therebetween, wherein,

the first coupling beam is movable both in the first direction and in the second direction.

22. The angular velocity sensor of claim 21, wherein

the first and second drive members, the first and second detection members, and the first coupling beam are located in the space, and

the space is sealed.

23. An angular velocity sensor, comprising:

a first oscillator configured to vibrate in a predetermined direction;

a second oscillator configured to vibrate in the predetermined direction; and

a coupling beam configured to couple the first and second oscillators together in such a manner that the first and second oscillators vibrate relative to each other in the predetermined direction, wherein

the coupling beam includes a first post portion joined to a surface of the first oscillator, a second post portion joined to a surface of the second oscillator, and a spring portion having elasticity in the predetermined direction,

the first post portion extends away from the surface of the first oscillator in a thickness direction of the first oscillator,

the second post portion extends away from the surface of the second oscillator in a thickness direction of the second oscillator, and

the spring portion joins the first post portion to the second post portion and is spaced from the first and second oscillators.

24. The angular velocity sensor of claim 23, wherein

the first post portion is joined to the surface of the first oscillator at a position corresponding to a center of gravity of the first oscillator, and

the second post portion is joined to the surface of the second oscillator at a position corresponding to a center of gravity of the second oscillator.

25. The angular velocity sensor of claim 23, wherein

the first oscillator includes a first portion having first and second ends in the predetermined direction and a second portion joined to the first end of the first portion, a longitudinal direction of the first portion being parallel to the predetermined direction,

the second oscillator includes a third portion having first and second ends in the predetermined direction and a fourth portion joined to the first end of the third portion, a longitudinal direction of the third portion being parallel to the predetermined direction,

the first post portion of the coupling beam is joined to the second portion of the first oscillator,

the second post portion of the coupling beam is joined to the fourth portion of the second oscillator,

the first end of the first portion of the first oscillator is located closer to the second oscillator than the second end of the first portion of the first oscillator, and

the first end of the third portion of the second oscillator is located closer to the first oscillator than the second end of the third portion of the second oscillator.

26. The angular velocity sensor of claim 23, further comprising:

a spring member joined to the coupling beam, wherein

the first post portion, the second post portion, and the spring member are located on a straight line.

27. The angular velocity sensor of claim 26, wherein

the coupling beam, the first oscillator, the second oscillator, and the spring member are electrically connected together.

28. The angular velocity sensor of claim 23, wherein

the coupling beam has elasticity in the predetermined direction.

29. The angular velocity sensor of claim 23, wherein

the first and second oscillators are located on a common plane parallel to the predetermined direction.

30. The angular velocity sensor of claim 23, wherein

the first and second oscillators are made of silicon, metal, resin, glass, ceramic, or a mixture of at least two of these materials.

31. The angular velocity sensor of claim 23, wherein

the coupling beam has an acute portion that forms an acute angle with respect to the predetermined direction.

32. The angular velocity sensor of claim 23, wherein

a first layer where the first and second oscillators are formed, and

a second layer where the coupling beam is formed, the second layer located to face the first layer to define a space therebetween, wherein,

the coupling beam is movable in the predetermined direction.

33. The angular velocity sensor of claim 32, wherein

the first oscillator, the second oscillator, and the coupling beam are located in the space, and

the space is sealed.

34. An angular velocity sensor comprising

a first oscillator configured to vibrate in a predetermined direction;

.

a second oscillator configured to vibrate in the predetermined direction; and

a pair of first and second coupling beams configured to couple the first and second oscillators together in such a manner that the first and second oscillators vibrate relative to each other in the predetermined direction, wherein

the first coupling beam includes a first post portion joined to a front surface of the first oscillator, a second post portion joined to a front surface of the second oscillator, and a first spring portion having elasticity in the predetermined direction,

the first post portion extends away from the front surface of the first oscillator in a thickness direction of the first oscillator,

the second post portion extends away from the front surface of the second oscillator in a thickness direction of the second oscillator, and

the first spring portion joins the first post portion to the second post portion and is spaced from the front surfaces of the first and second oscillators,

the second coupling beam includes a third post portion joined to a back surface of the first oscillator, a fourth post portion joined to a back surface of the second oscillator, and a second spring portion having elasticity in the predetermined direction,

the third post portion extends away from the back surface of the first oscillator in the thickness direction of the first oscillator,

the fourth post portion extends away from the back surface of the second oscillator in the thickness direction of the second oscillator, and

the second spring portion joins the third post portion to the fourth post portion and is spaced from the back surfaces of first and second oscillators.

35. The angular velocity sensor of claim 34, wherein

the first post portion is joined to the front surface of the first oscillator at a position corresponding to a center of gravity of the first oscillator,

the second post portion is joined to the front surface of the second oscillator at a position corresponding to a center of gravity of the second oscillator,

the third post portion is joined to the back surface of the first oscillator at a position corresponding to the center of gravity of the first oscillator, and

the fourth post portion is joined to the back surface of the second oscillator at a position corresponding to the center of gravity of the second oscillator.

36. The angular velocity sensor of claim 34, wherein

the first oscillator includes a first portion having first and second ends in the predetermined direction and a second portion joined to the first end of the first portion, a longitudinal direction of the first portion being parallel to the predetermined direction,

the second oscillator includes a third portion having first and second ends in the predetermined direction and a fourth portion joined to the first end of the third portion, a longitudinal direction of the third portion being parallel to the predetermined direction,

the first post portion of the first coupling beam is joined to a front surface of the second portion of the first oscillator,

the second post portion of the first coupling beam is joined to a front-surface of the fourth portion of the second oscillator,

the third post portion of the second coupling beam is joined to a back surface of the second portion of the first oscillator,

the fourth post portion of the second coupling beam is joined to a back surface of the fourth portion of the second oscillator,

the first end of the first portion of the first oscillator is located closer to the second oscillator than the second end of the first portion of the first oscillator, and

the first end of the third portion of the second oscillator is located closer to the first oscillator than the second end of the third portion of the second oscillator.

37. The angular velocity sensor of claim 34, wherein

the first and second coupling beams are made of silicon, metal, resin, glass, ceramic, or a mixture of at least two of these materials.

38. The angular velocity sensor of claim 34, wherein

the first and second coupling beams have an arch shape.

39. The angular velocity sensor of claim 34, wherein

the first and second coupling beams have a circular shape.

40. An angular velocity sensor comprising:

at least two sensor units, each sensor unit comprising;

a drive weight movable in a first direction;

a detection weight movable in a second direction perpendicular to the first direction; and

a middle weight located between the drive weight and the detection weight, the middle weight configured to move in the first direction when the drive weight moves in the first direction, the middle weight configured to cause the detection weight to move in the second direction when the middle weight moves in the second direction; and

a coupling beam configured to couple the middle weights of the at least two sensor units together by crossing over the drive weights of the at least two sensor units or the detection weights of the at least two sensor units.