JPH09229683A - Inclination detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out highly precise measurement with excellent linearity by providing a non-magnetic container which contains a spherical body made of a magnetic body in the inside and has a spherical space having larger diameter than that of the spherical body and magnetic poles installed at positions, which are points of contact of the spherical space and a cubic body circumscribing the spherical space. SOLUTION: A spherical body 1 is a magnetic body and made of an iron ball. A container 2 has a spherical space to contain the spherical body 1 and is made of a non-magnetic synthetic resin. A diameter of the spherical space of the container 2 is made wider than that of the spherical body 1, so that the spherical body 1 can move in the container 2. Magnetic poles 3-8 are installed at positions which are the points of contact of the spherical space and a cubic body circumscribing the spherical space. Coils 13-18 are coiled on respective magnetic poles 3-8 and a.c. current is applied to one side of each coil as an excitation side and the induction voltage increases more in the other side, which is a detection side, as the spherical body 1 comes closer. The magnetic poles 3-8 are connected with a yoke 10 made of a magnetic body and the yoke 10 works also as a magnetic shield. Of the coils, coils 13 and 14, coils 15 and 16, and coils 17 and 18 are differentially connected, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt detecting device used for underwater and aerial vehicles, industrial machines, consumer machines and the like.

[0002]

2. Description of the Related Art Conventionally, in order to detect a tilt angle on a polar coordinate of a space, it is necessary to arrange a plurality of tilt detecting devices for each of the X, Y and Z axes, and calculate the output from those devices. was there. In general, it takes a lot of time and effort to arrange the sensor axes relatively perpendicular to the X, Y, and Z axes, and there is a problem that the occupied volume becomes large.

As an inclination detecting device which solves such a problem, there is one shown in Japanese Patent Laid-Open No. 59-178313. The tilt detecting device described in this publication is equipped with a pair of proximity sensors on the X, Y, and Z axes of an orthogonal coordinate system whose origin is the center of the spherical container, and outputs signals from a total of six proximity sensors. The calculation is intended to detect the inclination. By doing this,
Since it suffices to attach the proximity sensors to each of the six attachment positions provided in advance on the sphere, the labor of adjustment can be considerably omitted.

[0004]

However, in the inclination detecting device described in the above publication, the proximity sensors are separately arranged at the six mounting positions provided on the spherical container, but the characteristics of each sensor are different. It was difficult to easily obtain the linearity of the signal and high accuracy due to the influence of the variation of the above and the influence of the subtle difference in the mounting state at each mounting position.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a tilt detecting device which has excellent signal linearity and can perform highly accurate measurement.

[0006]

The inclination detecting apparatus of the present invention made to solve the above-mentioned problems has a spherical body made of a magnetic material and a spherical space which contains the spherical body and has a larger diameter than the spherical body. A container made of a magnetic material, six magnetic poles provided at positions corresponding to the contact points of a cube and a spherical space circumscribing the spherical space of the container, and two sets of windings wound around each magnetic pole. One side is an excitation side, and an alternating current for excitation is commonly applied to each magnetic pole winding, and the other side is a detection side in which windings of mutually facing magnetic poles are differentially connected and the outside of the magnetic poles. It is characterized by having a yoke made of a magnetic material in which In addition, in the second invention, which has been further improved, in order to use the damper when used in a place where there is a lot of vibration, in addition to the above-mentioned configuration, a chemically non-existent space enclosed in the space formed between the container and the sphere is used. It is characterized by having an active liquid.

In the inclination detecting device of the present invention, the sphere inside the container having the spherical space is always drawn in the direction of gravity. Accordingly, the distance between the six magnetic poles surrounding the sphere and the sphere is determined. Two sets of windings are wound around each magnetic pole, and one side is an excitation side, and an alternating current for excitation is commonly applied to each magnetic pole winding. The other side is the detection side, and the windings of the magnetic poles facing each other are differentially connected. It is easy to wind windings of the same wire diameter and the same material on the facing magnetic poles the same number of times.Detecting each magnetic pole when an AC current is sent from the same oscillator to each excitation side and a magnetic substance approaches the magnetic poles. If we measure the induced voltage on the side, it will be possible to have very similar characteristics. Further, since the moving range of the magnetic body is limited to the space between both magnetic poles, only the portion having good linearity can be used by reducing the distance between the magnetic poles. Operate and connect the windings on the detection side of the facing magnetic poles so that the phases are reversed,
When measuring the position of the magnetic substance between the magnetic poles, when the magnetic substance is equidistant from both magnetic poles, the output on the detection side becomes the same voltage and cancels each other out to zero. That is, it is not necessary to adjust the zero point. Further, even with respect to the temperature drift, the signals from the detection windings of the respective magnetic poles are shifted by the same amount, but since the signals are different from each other, they are canceled and the influence on the accuracy can be suppressed.

Since such characteristics are the same for the three pairs of magnetic poles, the pair of magnetic poles is used as the X-axis, Y-axis, and Z-axis components on the Cartesian coordinates of the space without any special adjustment. Can be taken out with high accuracy.

Since the sphere exists on the wall surface in the rest space in the direction of being pulled by gravity, the vector of the position of the sphere with the center of the spherical space as the origin indicates the direction of gravity.

Further, the X-axis, Y-axis, Z on the Cartesian coordinates of the space
From the axis component, the inclination from the vertical axis on the polar coordinates of the space and the angle in the horizontal plane can be obtained by the calculation by the conversion formula from the rectangular coordinates to the polar coordinates.

In addition to the above, according to the second aspect of the invention, when used in a place where there is a lot of vibration, due to the viscous resistance to the movement of the inside sphere due to the liquid having an appropriate viscosity filling the spherical space. It can be used stably by applying a damper.

As described above, it is possible to more easily obtain the inclination detecting device having better linearity and accuracy.

[0013]

FIG. 1 is a sectional view showing an embodiment of claim 1 of the present invention.

In FIG. 1, reference numeral 1 is a magnetic sphere,
For example, an iron ball is used. Reference numeral 2 denotes a container made of a non-magnetic material having a spherical space that encloses the spherical body 1, for example, synthetic resin is used. It should be noted that the diameter of the spherical space of the container 2 is such that the sphere 1 can move within the container.
It is larger than the diameter of.

The container 2 is provided with a total of six magnetic poles 3, 4, 5, 6, 7, and 8 at the positions corresponding to the contact points between the cube circumscribing the spherical space and the spherical space. That is, X, Y, Z with the origin of the center of the spherical space of the container 2
Considering Cartesian coordinates, two magnetic poles are installed on each coordinate axis so as to face each other.

Windings 13, 14, 15, 16, 17, and 18 are wound around the magnetic poles 3, 4, 5, 6, 7, and 8. There are two sets of each winding, and one side is an excitation side and an alternating current is passed through. The other is the detection side, and each magnetic pole is 3-8.
The induced voltage increases as the spherical body 1 made of a magnetic material approaches.

The magnetic poles 3 to 8 are connected to a yoke 10 made of a magnetic material. The yoke 10 covers the whole and also serves as a magnetic shield.

Since the sphere 1 can move only in a spherical space, the position of the sphere viewed from the origin means the direction of gravity in the space.

FIG. 2 shows a block diagram of the signal processing section. For each magnetic pole, 3 and 4 are the X axis, 5 and 6 are the Y axis, and 7 and 8
Are arranged to detect the position of the sphere in the Z-axis direction, and the windings 13, 14, 15, 16, 17, 18 of each magnetic pole are arranged.
The detection side windings are 13 and 14, 15 and 16, 17 and 18
Are differentially connected.

The signal from the detection side of the windings 13 and 14 passes through the detector 19 and further through the filter 20. As a result of the above operation, information about the X axis of the position of the sphere 1 is the voltage signal Vx.
Is obtained as Similarly, a signal from the detection side of the windings 15 and 16 passes through the detector 21 and the filter 22 and becomes a voltage signal Vy as information about the Y axis of the position of the sphere 1, and a signal from the detection side of the windings 17 and 18. Passes through the detector 23 and the filter 24 and becomes a voltage signal Vz as information about the Z axis of the position of the sphere 1.

Each axis voltage signal Vx, Vy, Vz is A / D
Each of them is converted into a digital signal by the converter 25.
The digitized signal is processed by the CPU 11 and the RAM 26 by the program written in the ROM 12, and the parallel signal output is the parallel output port 2
7. The serial signal output is the serial port 28,
The output as an analog voltage is output from the D / A converter 29.

Next, the outline of the signal processing by the program will be described with reference to FIG. Vx, Vy, Vz, which means the components of each coordinate axis in the rectangular coordinates of the space, are converted into the polar coordinates of the rectangular coordinates by the following formulas (1) and (2) that are polar coordinates of the space. It is converted to the component of the inclination from the vertical axis in and the inclination in the horizontal plane.

Inclination from the vertical axis ψ: ψ = Arctan (√ (Vx ² + Vy ² ) / Vz) (1) Inclination in the horizontal plane θ: θ = Arctan (Vy / Vx) (2)

Next, an embodiment of the second invention will be described. The principle of operation is the same as that of the above-mentioned embodiment, so that it is omitted and only different parts will be described. In the above embodiment, the sphere 1 moves in a spherical space, but in this embodiment, a chemically inert liquid whose viscosity can be adjusted, such as silicone oil, is enclosed in the spherical space.

As a result, the spherical body 1 receives the viscous resistance of the liquid, which acts as a damper and can be stably operated even in the presence of vibration.

[0026]

According to the inclination detecting device of the present invention, it is possible to perform detection with good linearity on each coordinate axis and with uniform characteristics, and it is not necessary to adjust the zero point due to the operation connection of the position detecting means having uniform characteristics, and there is no temperature drift. It is possible to suppress the influence on.
Furthermore, since it is integrated, there is also a feature that adjustment of each axis is not required at the time of assembly.

Further, since it is possible to detect the tilt component from the vertical axis in the polar coordinates of the space and the tilt component in the horizontal plane by one tilt detecting device, it is troublesome to mount the plurality of tilt detecting devices at a right angle. Therefore, the occupied volume can be reduced. Furthermore, since it is magnetically shielded by surrounding the whole with a yoke, it is less susceptible to the external magnetic field.

Secondly, according to the second aspect of the invention, in addition to the above characteristics, the damper is effective when used in a place where there is a lot of vibration, so that the device can be operated stably even in a place where there is vibration.

[Brief description of drawings]

1A and 1B are cross-sectional views of a tilt detecting device according to an embodiment of the present invention, in which FIG. 1A is a CC ′ cross section, FIG. 1B is an AA ′ cross section, and FIG. 1C is a BB ′ cross section. Is.

FIG. 2 is a block diagram of a signal processing unit of the inclination detection device which is an embodiment of the present invention.

FIG. 3 is an explanatory diagram of coordinate conversion in space.

[Explanation of symbols]

 1: spherical body (magnetic body) 2: container (non-magnetic body) 3, 4: X-axis direction magnetic pole 5, 6: Y-axis direction magnetic pole 7, 8: Z-axis direction magnetic pole 9: excitation oscillation circuit 10: Yoke iron 11: CPU 12: ROM 13, 14: X-axis magnetic pole winding 15, 16: Y-axis magnetic pole winding 17, 18: Z-axis magnetic pole winding 25: A / D converter 26: RAM 27: Parallel output port 28: Serial port 29: D / A converter

Claims (2)

[Claims] 1. A spherical body made of a magnetic material, a container made of a non-magnetic material which contains the spherical body and has a spherical space having a diameter larger than that of the spherical body, and a cube and a spherical space which circumscribe the spherical space of the container. There are six magnetic poles provided at positions corresponding to the contact points with two magnetic poles, and two pairs of windings are wound around the magnetic poles, one of which is the excitation side, and an alternating current for excitation is commonly applied to each magnetic pole winding. The other one is, on the detection side, one in which windings of opposite magnetic poles facing each other are differentially connected, and a yoke made of a magnetic material connecting the outside of the magnetic poles is provided. . 2. The tilt detecting device according to claim 1, wherein a chemically inert liquid is sealed in a space formed between the container and the sphere.