JP2539887Y2 - Magnetic tilt angle sensor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tilt angle sensor formed by using a magnetoresistive element.

[0002]

2. Description of the Related Art For example, an inclination angle sensor is used as a sensor for detecting an inclination of a video camera, a table surface or the like. FIG. 4 shows a general tilt angle sensor of this type. In the conventional tilt angle sensor, an adapter 3 is fixed to a rotating shaft 2 of a potentiometer 1, an arm 4 is projected downward from the adapter 3, a weight 5 is fixed to a lower end side of the arm 4, and a case of the potentiometer 1 is provided. 6 is fixed to a base 7 or the like to be measured.

According to this inclination angle sensor, the weight 6 always faces vertically downward with respect to the rotating shaft 2, so that the base 7
When the rotary shaft 2 is tilted only by one angle, the rotary shaft 2 rotates relative to the base 7 (case 6) by θ, and the amount of rotation of the rotary shaft 2 is converted into an electric signal and taken out.

[0004]

However, since the conventional inclination angle sensor has a structure in which the weight 5 is attached to the potentiometer 1, the structure of the device is complicated and large, and the size of the device is increased and the cost of the device is increased. There was a problem.

The present invention has been made to solve the above-mentioned conventional problems, and its object is to provide a simple device configuration.
Another object of the present invention is to provide a small and inexpensive magnetic tilt angle sensor.

[0006]

The present invention is configured as follows to achieve the above object. That is, in the magnetic tilt angle sensor of the present invention, a rotating shaft is fixed to a rotating body formed of a magnetic material, and the rotating shaft is rotatably supported by a bearing portion, and the rotating body is connected to the rotating shaft. The lower side of the rotating body is made heavier than the upper side by disturbing the upper and lower weight balance, and a magnetoresistive element is disposed below the rotating body so as to face the peripheral end surface of the rotating body. The end face is characterized in that the position facing the magnetoresistive element is shifted in the direction of the axis of the rotating shaft by the rotation of the rotating body, so that the end face is formed as a sectioned surface of a spiral shape.

[0007]

In the present invention having the above structure, when the base is inclined by θ with the bearing portion supporting the rotating shaft of the rotating body attached to, for example, the base of the object to be measured, the rotating body is rotated by the rotating shaft. , The lower side is heavier than the upper side, so the lower side of the rotating body always faces the direction of gravity, and the rotating shaft rotates integrally with the rotating body by θ relative to the base. . As a result of the rotation of the rotator, the opposing surface of the rotator facing the magnetoresistive element is displaced in the axial direction of the rotation axis. As a result, the amount of displacement of the opposing surface, that is, the amount of rotation of the rotator (the tilt angle of the base) is supported. Is obtained as a detection signal.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of an embodiment of a magnetic tilt angle sensor according to the present invention. In the figure, bearing portions 10 are provided on both left and right sides of the case frame 8.
A rotating shaft 11 supported in a horizontal direction and hung in the horizontal direction is rotatably disposed. A rotating body is located almost in the middle of the rotating shaft 11.
12 are fixed.

The rotating body 12 is formed of a magnetic material, and the shape of the peripheral end face 13 is a section of a spiral shape, in other words, a state in which a part of the spiral length of the top surface of the thread is taken out. It is formed in the shape of. Also, the upper part of the rotary shaft 11 is cut off, and the weight balance is lost on both the upper and lower sides,
The lower side of the rotating shaft 11 is made heavier than the upper side, and the center of gravity G of the lower side of the rotating body 12 is always directed to the direction of gravity, that is, vertically downward.

A magnetoresistive element 14 is disposed below the rotating body 12 so as to face the spiral end surface 13 of the rotating body 12. As shown in FIG. 2, the magnetoresistive element 14 has magnetoresistive element elements 14a and 14b arranged above a bias magnet 15, connects the element elements 14a and 14b in series, and connects one end of the element elements to a power supply line. The other end is connected to a ground line, and the connection between the element elements 14a and 14b is used as a detection signal extraction section.

This embodiment is configured as described above.
Next, the operation of detecting the inclination angle by the device of the present embodiment will be described. When the base frame 7 is tilted by θ in a state where the case frame 8 is attached to the base 7 to be measured whose tilt angle is to be measured as shown in FIG. 3 of the conventional example, the center of gravity G of the rotating body 12 becomes The rotator 12 rotates by θ relative to the base 7 because the rotator 12 is directed in the direction of gravity. Due to the rotation of the rotating body 12, the position of the surface of the rotating end face 13 facing the magnetoresistive element 14 is shifted in the axial direction of the rotating shaft 11 by an amount corresponding to the rotation angle θ. That is, as shown in FIG.
When the peripheral end face 13 is rotated only by a predetermined angle, the opposing position of the peripheral end face 13 moves in the direction from the element elements 14a to 14b of the magnetoresistive element 14 or in the direction from the element elements 14b to 14a in accordance with the inclination direction of θ. By the movement of the opposing position of the peripheral end face 13, the magnitude of the detection signal of the magnetoresistive element 14 changes within the level range from A to B of the detection signal shown in FIG. An inclination angle is required.

The present invention is not limited to the above embodiment, but can take various embodiments. For example, in the above-described embodiment, the upper and lower sides of the rotating body 12 are notched to break the weight balance of the upper and lower sides of the rotating body 12, but without such a notch, a weight is placed on the lower side of the rotating body 12. The weight balance between the upper and lower sides may be broken by embedding, or the upper side of the rotating body 12 is cut out as in the present embodiment,
Furthermore, a weight is embedded in the lower portion of the rotating body 12 to greatly break the weight balance between the upper and lower sides, so that when the base 7 to be measured is tilted, the center of gravity position G is immediately directed to the direction of gravity by the amount of the tilt. Alternatively, the responsiveness of the measurement may be increased.

[0013]

According to the present invention, a rotating body whose upper and lower weight balance is broken is fixed to a rotating shaft rotatably held in a bearing portion, and a peripheral end face of the rotating body is formed as a spiral-shaped one-part surface. Since the magnetoresistive element is provided on the lower side of the rotating body so as to face the peripheral end face of the rotating body, the inclination of the object to be measured is shifted by the amount of displacement of the spiral peripheral end face facing the magnetoresistive element. Can be detected, and the configuration of the device can be extremely simplified without using a potentiometer or a weight as in the conventional example, thereby facilitating the manufacture of the device and reducing the size of the device. Can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a magnetic tilt angle sensor according to the present invention.

FIG. 2 is an explanatory diagram showing an example of an operation of detecting an inclination angle by a magnetoresistive element constituting the embodiment.

FIG. 3 is an explanatory diagram of a sensor output level in the embodiment.

FIG. 4 is an explanatory view showing an example of a conventional inclination angle sensor.

[Description of Signs] 8 Case frame 10 Bearing 11 Rotary shaft 12 Rotary body 13 Peripheral end surface 14 Magnetoresistive element

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Chiki Ochiai 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Murata Manufacturing Co., Ltd. (56) References JP-A-3-28711 (JP, A)

Claims (1)

(57) [Scope of request for utility model registration] A rotating shaft is fixed to a rotating body formed of a magnetic material, and the rotating shaft is rotatably supported by a bearing portion. The rotating body balances up and down with respect to the rotating shaft. Break down and make the lower side heavier than the upper side,
A magnetoresistive element is disposed below the rotator so as to face the peripheral end surface of the rotator, and the position of the peripheral end surface of the rotator opposed to the magnetoresistive element by rotation of the rotator is the axis of the rotation axis. A magnetic tilt angle sensor having a spiral-shaped sectioned surface that is shifted in the longitudinal direction.