INCLINATION SENSOR

• US 20020050068A1
• Filed: 09/09/1999
• Published: 05/02/2002
• Est. Priority Date: 12/09/1997
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: NAKAGAKI, TOSHIYA, USHIHARA, MASAHARU, KATSUKI, NOBUHARU
• Granted Patent: US 6,499,220 B2
• Time in Patent Office: Days
• US Class Current: 33/391
• CPC Class Codes: G01C 2009/064 inductive
• CPC Class Codes: G01C 9/12 by using a single pendulum plumb lines G01C15/10

Abstract

An object of the present invention is to provide an inclination sensor that has a superior rotational performance and long term stability, and is high in detecting accuracy. In order to achieve the above object, the inclination sensor of the present invention comprises a pendulum (10) mounted rotatably relative to a case (1) of a fixing body to be fixed to a mounting body, a magnetic flux generation means (11) mounted on the pendulum (10), reed switches (4a) and (4b) mounted on a part of the case (1) corresponding with a rotational path of the magnetic flux generation means (11), and a flange part (12) having nonmagnetic and electrically conductive properties defining a damping body arranged on the case (1) along the rotational path of the magnetic flux generation means (11).

Claims

1. An inclination sensor comprising:

a pendulum mounted rotatably relative to a fixing body to be attached to a mounting body;

a magnetic flux generation means mounted on said pendulum;

a reed switch mounted on a part of said fixing body corresponding to a rotational path of said magnetic flux generation means; and

a damping body having nonmagnetic and electrically conductive properties positioned on said fixing body along the rotational path of said magnetic flux generation means.

2. The inclination sensor according to claim 1, wherein a frame is mounted within the fixing body.

3. The inclination sensor according to claim 2, wherein said frame is provided with a pair of substantially coaxial bearing retention holes, at least one of the bearing retention holes is formed with a thread, and said bearing retention hole having the thread is fitted by a bearing formed with a thread on periphery thereof.

4. The inclination sensor according to claim 1, wherein a rotary shaft axially fixed with said pendulum is supported by a bearing.

5. The inclination sensor according to claim 4, wherein said rotary shaft has a reduced diameter at both ends.

6. The inclination sensor according to claim 4, wherein the rotary shaft is provided with pins at both ends by one of fixation and insertion.

7. The inclination sensor according to claim 6, wherein the pins are 0.6 mm in diameter.

8. The inclination sensor according to claim 1, wherein said damping body is constructed in a direction parallel to an axial direction of the rotary shaft or in a manner to form a predetermined angle with the direction parallel to the axial direction of the rotary shaft.

9. The inclination sensor according to claim 1, wherein said damping body is formed in a shape of cylinder or circular arc.

10. The inclination sensor according to claim 1, comprising at least one pair of said reed switches.

11. The inclination sensor according to claim 1, comprising at least one pair of said magnetic flux generation means.

12. The inclination sensor according to claim 1, wherein said magnetic flux generation means comprises a magnet.

13. The inclination sensor according to claim 12, wherein said magnet is made of a samarium-cobalt system.

14. The inclination sensor according to claim 12, wherein said magnet is heat-treated at a temperature greater than a serviceable temperature thereof.

15. The inclination sensor according to claim 1, wherein a major plane surface of a leaf of said reed switch is substantially in parallel with an axial direction of the rotary shaft.

16. The inclination sensor according to claim 1, comprising an electric resistance inserted in parallel with said reed switch.

17. The inclination sensor according to claim 1, wherein said damping body is made of a material having a high electrical conductivity.

18. The inclination sensor according to claim 17, wherein said damping body is made of one of copper and aluminum.

19. The inclination sensor according to claim 1, wherein said frame is made of a material having a high electrical conductivity.

20. The inclination sensor according to claim 19, wherein said frame is made of one of copper, aluminum and brass.

21. The inclination sensor according to claim 1, comprising a magneto-detecting element provided in vicinity of said reed switch.

22. The inclination sensor according to claim 1, comprising at least one reflection type interrupter provided on the fixing body in a manner to face against a surface of said rotatory pendulum.

23. The inclination sensor according to claim 1, comprising at least one magnetic damping adjusting device made of a magnetic material provided adjustably of position thereof on the fixing body.

24. The inclination sensor according to claim 23, wherein the magnetic damping adjusting device is provided in a direction generally in parallel with an axial direction of the rotary axis, and said magnetic damping adjusting device comprises a threaded structure.

25. The inclination sensor according to claim 1, wherein a contact point of each leaf of said reed switch is mounted on the fixing body via a mechanism which is rotatably adjustable about the rotary shaft.

26. The inclination sensor according to claim 1, wherein said reed switch is mounted on the fixing body via a mechanism by which said reed switch is adjustable in an axial direction of the rotary shaft.

27. The inclination sensor according to claim 1, wherein said magnetic flux generation mean s and said reed switch are mounted in a manner that a polar axis of said magnetic flux generation means is in parallel with an axial direction of the rotary shaft, and a central axis in a longitudinal direction of said reed switch is in parallel with the axial direction of the rotary shaft.

28. The inclination sensor according to claim 1 or claim 27, wherein said damping body is composed of a part, which is formed in a one of a direction in parallel with an axial direction of the rotary shaft and a direction at a predetermined angle to the direction in parallel with the axial direction of the rotary shaft, and a part in a shape of flat plate in perpendicular to the rotary shaft.

29. The inclination sensor according to claim 1 or claim 27, wherein said damping body has a shape of flat plate located in vicinity of one of both ends and one end of said magnetic flux generation means in a direction of the polar axis, and in perpendicular to the rotary shaft.

30. The inclination sensor according to claim 28 or claim 29, wherein said damping body is mounted on the fixing body via a mechanism by which said reed switch is adjustable in an axial direction of the rotary shaft.

31. The inclination sensor according to claim 27, comprising a plurality of said magnetic flux generation means.

32. The inclination sensor according to claim 27, comprising at least a pair of said magnetic flux generation means, wherein polar orientations arranged in an axial direction of the rotary shaft are opposite to each other.

33. The inclination sensor according to claim 27, wherein a major plane surface of a leaf of said reed switch is one of substantially in parallel with and substantially perpendicular to a direction of a rotational radius of said pendulum.

34. The inclination sensor according to claim 27, comprising a mechanism by which a contact point of leafs of said reed switch is rotatably adjustable about the rotary shaft of said pendulum.

35. The inclination sensor according to claim 27, comprising a mechanism capable of adjusting said reed switch in an axial direction of the rotary shaft or in a direction of a rotational radius of said pendulum.

36. The inclination sensor according to claim 32, wherein said pair of said magnetic flux generation means are coupled with a yoke having magnetism.

38. The inclination sensor according to claim 37, wherein one of said divided frames is formed in shapes of letter U and reversed letter U at each halves of its major plane surface.

39. The inclination sensor according to claim 37, wherein said divided frames have a pair of bearings for axially supporting said pendulum, and said pair of the bearings have a threaded portion which is adjustable in a direction of the rotary shaft of said pendulum.

40. The inclination sensor according to claim 37, comprising a plurality of said reed switches.

41. The inclination sensor according to claim 37, wherein said damping body is in a shape of cylinder.

37. An inclination sensor comprising:

divided frames provided within a fixing body to be attached to a mounting body;

a pendulum rotatably mounted to said divided frames;

a magnetic flux generation means mounted on said pendulum;

a reed switch mounted on a part of said divided frames in a manner to correspond with a rotational path of said magnetic flux generation means; and

a damping body having nonmagnetic and electrically good conductive properties positioned on said divided frames along the rotational path of said magnetic flux generation means.

42. An inclination sensor comprising:

divided frames provided within a fixing body to be attached to a mounting body;

a pendulum rotatably mounted to said divided frames;

a magnetic flux generation means mounted on said pendulum; and

a reed switch mounted on one of said divided frames in a manner to correspond with a rotational path of said magnetic flux generation means,

wherein at least one of said divided frames is of an electrically good conductive material, arranged along the rotational path of said magnetic flux generation means.

43. The inclination sensor according to claim 42, wherein a damping body of a nonmagnetic and electrically good conductive material is positioned on said divided frames along an outermost perimeter of a rotational path of said magnetic flux generation means.

44. The inclination sensor according to claim 43, wherein said damping body is in a shape of cylinder.

45. The inclination sensor according to claim 42, wherein said divided frames have a pair of bearings for axially supporting said pendulum, and said pair of the bearings have a threaded portion with which the bearings are adjustable in a direction of the rotary shaft of said pendulum.

46. The inclination sensor according to claim 42, comprising a plurality of said reed switches.

48. The inclination sensor according to claim 47, wherein said frame is provided with a damping body having nonmagnetic and electrically good conductive properties.

49. The inclination sensor according to claim 48, wherein said damping body is in a shape of cylinder.

47. An inclination sensor comprising:

a frame made of an electrically good conductive material provided within a fixing body to be attached to a mounting body;

a pendulum rotatably mounted to said frame;

a magnetic flux generation means mounted on said pendulum; and

a reed switch mounted on a part of said frame in a manner to correspond with a rotational path of said magnetic flux generation means.