JP2003232632A - Inclination sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturizable inclination sensor in which the number of components is reduced and assembling capability is enhanced. <P>SOLUTION: A rotating shaft 23 is rotatably supported when a motor 22 is stopped. In this embodiment, a weight 24 is formed in an almost symmetrical shape as viewed from the rotating shaft direction, and is made from a permanent magnet magnetized so as to constitute an N pole and an S pole according to the almost symmetrical shape. When the motor 22 is stopped, since the rotating shaft 23 is rotatably supported, the symmetrical shaft of the weight 24 is rotated so as to point the vertical direction in the relation of gravity. The number of components such as a housing which is required in a current inclination sensor can be reduced, and since an adhering process (a connecting process) of the housing is made unnecessary in the production process, the assembling capability is enhanced, and the miniaturizable inclination sensor can be constructed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt sensor that outputs an electric signal indicating a tilt condition.

[0002]

2. Description of the Related Art Conventionally, as an inclination sensor using a magnetic sensor, as shown in FIG. 2, a movable permanent magnet 4 is provided in a bent storage chamber 10, and a magnet for detecting the magnetism of the permanent magnet 4 is used. There is known a structure in which the sensor 5 is arranged on at least one end of the storage chamber 10 on the outer surface of the housing 1.

When this tilt sensor is tilted,
The inclination state can be confirmed by moving the permanent magnet 4 in the storage chamber 10 and detecting a change in the surrounding magnetic flux density accompanied by the magnetic sensor 5 and outputting an electrical output signal. Such an inclination sensor is disclosed in, for example, Japanese Patent Publication 2001.
It is disclosed in Japanese Patent Publication No. 221634.

[0004]

However, with the above-mentioned configuration known in the related art, it is not possible to obtain a linear output with respect to the tilt angle, and the binary detection whether the object is tilted or not is detected. There was a problem of staying in.

Further, since the permanent magnet is mounted in the storage chamber, at least two housings (base and cover) are required, which causes a problem that the number of parts is increased.

Further, the process of adhering (connecting) the housing is indispensable during the manufacturing process, and there is a problem in assembling.

Moreover, another space for containing the magnetic sensor is required on the side opposite to the one end of the storage chamber, which has been a problem in promoting miniaturization.

Therefore, in view of such a problem, an object of the present invention is to provide an inclination sensor capable of reducing the number of parts, improving the assemblability, and downsizing.

[0009]

In order to achieve the above object, an inclination sensor according to the present invention comprises a weight of a vibration motor used in a mobile phone or the like made of a magnet,
The tilt angle is measured by detecting a change in magnetic flux density around the magnet due to the movement (or rotation) of the magnet with a magnetic detection element such as a Hall element.

According to a first aspect of the present invention, there is provided a tilt sensor having a motor, a weight attached to the rotation shaft of the motor in an eccentric state, and a magnetic detection element, wherein the rotation shaft is the The weight is a rotatably supported shaft when the motor is stopped, and the weight is a permanent magnet having a substantially symmetrical shape and magnetized so as to form an N pole and an S pole according to the substantially symmetrical shape. The magnetic detection element is characterized in that it is arranged at a position capable of detecting a change in magnetic flux density in the surroundings caused by the rotation of the weight.

According to a second aspect of the present invention, in the first aspect of the present invention, the weight is formed in a semicircular or fan-shaped cross section, and the longitudinal direction of the weight is of the motor. It is characterized in that it is attached to the rotary shaft of the motor at substantially the center of the semicircular shape or fan shape so as to be substantially aligned with the direction of the rotary shaft.

Various magnetic sensors such as Hall element, Hall IC, magnetoresistive effect element (MR), magnetoresistive effect IC (MRIC) and reed switch can be applied as the magnetic detecting element, and the tilt angle In order to detect the magnetic field, an analog output type magnetic detection element is desirable. On the other hand, when it is desired to detect only whether or not it is tilted, a digital output type magnetic detection element is desirable.

The material of the weight is not particularly limited, but since it is a permanent magnet, various mass-produced permanent magnets such as ferrite type, samarium-cobalt type, and neodymium type are applicable.

According to the present invention, by adopting the above configuration, the number of parts is reduced and the assembling property is improved. Furthermore, the case body that was used to configure the tilt sensor is no longer necessary, and the tilt sensor can be configured simply by placing it near the vibration motor where the magnetic detection element is originally placed, which makes it possible to reduce the size. It is possible to deal with various applications conveniently.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a partially transparent perspective view showing an inclination sensor according to this embodiment. In the figure, 21 is the whole vibration motor, 22 is the motor main body, 23 is the rotary shaft of the motor, 24 is a weight, and 25 is a magnetic detection element (for example, a Hall element or a Hall IC). In the present embodiment, the vibration motor 21 and the magnetic detection element 25
Will be described assuming that it is mounted on a control circuit board (not shown) of a mobile phone.

The rotary shaft 23 is rotatably supported when the motor 22 is stopped. In the present embodiment, the weight 24 has a substantially symmetrical shape when viewed from the rotation axis direction, and is composed of a permanent magnet magnetized so as to form an N pole and an S pole in accordance with the substantially symmetrical shape. When the motor 22 is stopped, since the rotating shaft 23 is rotatably supported, the symmetry axis of the weight 24 rotates in a vertical direction due to gravity.

The magnetic detection element 25 is a mounting substrate (not shown)
Since it is arranged above, the vibration motor 21
The positional relationship with and is always constant, but the relationship with the weight 24 uniquely changes depending on the tilted state of the mobile phone. That is,
Depending on the tilted state of the mobile phone, the magnetic detection element 25 and the weight 2
Since the relative positional relationship with respect to 4 is determined, by detecting the magnetic flux density generated from the weight 24 by the magnetic detection element 25, the tilted state of the mobile phone can be detected.

In FIG. 1, the shape of the weight 24 is a fan shape, but the center angle of this fan shape may be larger than 180 degrees. The larger the central angle, the larger the tilt angle that can be detected. The NS direction of the weight 24 is not particularly limited.

By magnetizing the weight 24 as shown in FIG. 1, it is possible to determine whether the weight 24 is tilted in the N-pole direction or the S-pole direction with the symmetry plane of the weight 24 as the origin. Since the magnetic flux density changes depending on the angle, the tilt situation can be uniquely determined.

Regarding the shape of the weight 24 and the magnetizing method,
In addition, by having various shapes and magnetizing methods, the function of the tilt sensor can be satisfied.

The present invention is not limited to the above examples,
Further, various modifications can be implemented.

[0023]

As described above, according to the present invention, there is provided a tilt sensor having a motor, a weight attached to the rotation shaft of the motor in an eccentric state, and a magnetic detection element,
The rotating shaft is rotatably supported when the motor is stopped, the weight has a substantially symmetrical shape, and is magnetized so as to form an N pole and an S pole as the substantially symmetrical shape. Since it is a permanent magnet, and the magnetic detection element is arranged at a position where it is possible to detect a change in the surrounding magnetic flux density that occurs with the rotation of the weight, it is possible to reduce the number of parts such as a housing required for a conventional tilt sensor. In addition to being able to perform the manufacturing process, the process of bonding (connecting) the housing is not necessary, improving the assemblability and enabling downsizing. Can be provided.

[Brief description of drawings]

FIG. 1 is a partially transparent perspective view showing an example of a tilt sensor to which the present invention is applied.

FIG. 2 is a sensor sectional view showing an example of a conventionally known tilt sensor.

[Explanation of symbols]

1 housing 2 base 3 cover 4 permanent magnet 5 Magnetic sensor 10 storage rooms 11,12 Straight groove 13 arc surface 21 Vibration motor 22 motor 23 rotation axis 24 weights 25 Magnetic detection element

Claims (2)

[Claims] 1. A tilt sensor having a motor, a weight mounted eccentrically on a rotation shaft of the motor, and a magnetic detection element, wherein the rotation shaft is rotatable when the motor is stopped. The weight is a permanent magnet that has a substantially symmetrical shape and is magnetized so as to form an N pole and an S pole as the substantially symmetrical shape. An inclination sensor, wherein the inclination sensor is arranged at a position where a change in magnetic flux density in the surroundings caused by rotation can be detected. 2. The weight has a cross-sectional shape formed in a semicircular shape or a fan shape, and the longitudinal direction thereof is substantially aligned with the rotation axis direction of the motor, and the weight is approximately at the center of the semicircular shape or the fan shape. The tilt sensor according to claim 1, wherein the tilt sensor is attached to the rotary shaft of the motor.