JPH0567182B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a static rotation angle or inclination angle with respect to a vertical axis, an angular velocity of rotation about an arbitrary axis,
The present invention relates to a rotation sensor used to detect rotational mechanical quantities such as angular acceleration.

[Prior art] Multiple electrodes are provided inside an annular or long tubular container,
A tubular container in which a conductive liquid and air bubbles are sealed, and the inclination angle of the container is detected from the electrical resistance or impedance between each electrode that changes as the air bubbles move as the container inclines. Type tilt angle sensors are known.

However, with this sensor, it is difficult to fill in the amount of air bubbles as designed during manufacturing, distortions such as unevenness on the inner surface of the container directly affect the detection characteristics when the container is tilted, thermal expansion and contraction of air bubbles is large, and vertical axis Rotation angle, which is unsuitable for detecting rotation around
There were fundamental problems such as the inability to expand the structure to detect acceleration, etc.

[Problems to be Solved by the Invention] An object of the present invention is to use a solid mass to change the electrical impedance within a conductive liquid container, by using a solid mass instead of a foreign object, that is, a bubble in the sensor. In order to obtain the detection accuracy as designed regardless of the unevenness of the The object of the present invention is to provide a rotation sensor of a tubular container-pendulum system that is capable of detecting dynamic physical quantities such as angular velocity and angular acceleration.

[Means for Solving the Problems] A first invention for achieving the above object allows displacement in the longitudinal direction in the longitudinal center of a long tubular container whose interior is filled with a conductive liquid. A solid mass is supported by a support means such as a spring or a support string, and a center electrode and an end electrode are provided at the center and both ends in the longitudinal direction of the container, and the mass is affected by gravity or rotational external force. A flow path constriction member that changes the cross-sectional area of the current flow path between the center electrode and the end electrodes by displacement in the longitudinal direction is attached, and the electrical impedance between the center electrode and the end electrodes changes. Based on this, technical means are used to make it possible to detect the tilt angle, the angular velocity of rotation, and the angular acceleration.

In addition, a second invention that achieves the same object as the first invention is to provide an electrode on the solid mass described above and use it as a movable electrode that moves with the mass, and at both ends in the longitudinal direction of the container. An end electrode is provided, and the distance between the center electrode and the end electrode can be changed by displacement in the longitudinal direction of the mass due to gravity or rotary external force, and the distance between the center electrode and the end electrode can be changed. A technical means is used in which the tilt angle, the angular velocity of rotation, and the angular acceleration can be detected based on changes in electrical impedance.

[Function] The rotation sensor configured as described above has the following effects: when a mass disposed at the center in the longitudinal direction of a long tubular container is supported by a support string, it is tilted with respect to the gravity axis; The mass moves and tilts depending on the inclination with respect to the axis of gravity and the speed or acceleration of rotation. In this case, (1) If the mass is equipped with a flow channel constriction member that changes the cross-sectional area of the current flow path, the change in the cross-sectional area of the current flow path due to the flow constriction member, and (2) the mass If a movable electrode is provided on top that moves with the movable electrode, the electric impedance between the electrodes changes due to a change in the current flow path length between the movable electrode and the end electrode.

Therefore, the tilt angle, the angular velocity of rotation, the angular acceleration, etc. can be detected based on the change in electrical impedance.

This rotation sensor has a solid mass placed at the center of the long-tubular container in the longitudinal direction, and is configured almost symmetrically across the center, so the electrical impedance described above can be easily obtained as a differential signal output. and
In addition, instead of air bubbles, which are difficult to control the amount of injection and are easily affected by the inner wall properties of the container, we have used a solid mass supported by support strings or springs as a foreign substance that expands, narrows, increases or decreases the current flow path. Because it is used, it is not affected by the manufacturing accuracy or properties of the inner wall of the container.
Moreover, since the volume of the mass remains unchanged, it is possible to operate accurately as designed.

[Example] In each of the embodiments shown in FIGS. 1 to 3, the cross-sectional area of the current flow path between the electrodes is changed by a flow path constriction member, and the inclination angle or It is possible to detect the angular velocity, angular acceleration, etc. of rotation, and the embodiments shown in FIGS. 4 and 5 change the distance between the electrodes and based on the change in electrical impedance between the electrodes, It is possible to detect the tilt angle, the angular velocity of rotation, and the angular acceleration.

First, in the embodiment shown in FIG. 1, a long tubular container 1 made of an electrically insulating material is provided.
A solid mass 2 is disposed at the central portion 1a in the longitudinal direction of the
It is supported by the container 1 by support means 3 constituted by a spring that allows displacement in the longitudinal direction. As the support means 3, it is possible to use not only a spring but also a means such as a support string that allows displacement in the longitudinal direction and supports it. Further, a center electrode 4 is provided at the center portion 1a of the container 1, and end electrodes 5 are provided at symmetrical positions at both ends in the longitudinal direction. It is filled with These center electrode 4 and each end electrode 5, 5 are connected to a detection circuit (not shown) for detecting a change in electrical impedance between these electrodes.

A passage constricting member 7 is attached to the mass 2, which moves in and out of the left and right container tubular portions when the mass 2 moves left and right.

Therefore, if the position of the mass 2 is displaced from the center to the left or right due to gravity acting on the mass 2 in the direction of inclination as the container 1 is tilted, or due to a variable external force in the long axis direction of the long tubular container due to rotation, etc. , the flow path narrowing member 7 enters and exits the left and right container tubular portions, and on the side where the flow path narrowing member 7 enters the container tubular portion, the electrical impedance increases due to the narrowing of the current flow path, and the flow path narrowing member 7 comes out. By detecting the differential amount, the tilt angle or rotational angular velocity and angular acceleration can be detected.

In the embodiment shown in FIG. 2, the container 11 is constructed by sandwiching the ring-shaped outer wall 11a, inner wall 11b, and central support stand 11c between a pair of end plates, and the outer wall 11a and the inner wall 11b are sandwiched between a pair of end plates. A long tubular container portion is formed between them, and a notch is provided at the lower part of the inner wall 11b. Support stand 1 in the center of container 11
1c, a solid mass 12 that reaches between the outer wall 11a and the inner wall 11b through the above-mentioned notch is suspended by a spring constituting the support means 13, and this mass 12 has an arc-shaped structure on both sides. A channel constricting member 17 is provided that protrudes from the flow path constricting member 17 . In addition, the container 11
A center electrode 14 is provided at the center of the lower part of the container, and end electrodes 15 are provided at symmetrical positions on the left and right upper portions, and the inside of the container 11 is filled with a conductive liquid 16.

Note that, as the support means 13, it goes without saying that not only a spring but also a support string or the like can be used. Further, in the figure, 18 indicates an air vent.

In the embodiment shown in FIG. 3, two of the rotation sensors shown in FIG. 1 are connected in series, and the integrated container 21
is formed by an annular container portion 21a formed by connecting long tubular containers in two sensors, and a central portion 21b connecting opposing positions in the center of the container portions 21a in the diametrical direction. The solid masses 22, 22 of both sensors are tiltably supported by support means 23 consisting of a spring at an intermediate position of the central portion 21b, and when both masses are stretched in opposite directions and are tilted from side to side. Channel constricting members 27 that go in and out of the left and right annular container portions 21a are attached in a symmetrical manner.

Further, center electrodes 24, 24 are provided near the support means 23 in the center portion 21b of the container, and end electrodes 25 common to both sensors are provided at symmetrical positions on both sides of the annular container portion 21a. 2
1 is filled with a conductive liquid 26. These center electrode 24 and each end electrode 25, 25 are connected to a detection circuit (not shown) for detecting a change in electrical impedance between these electrodes.

According to such a composite sensor, the differential signal output of the output signals of both sensors can be made to respond to the rotational angular velocity and angular acceleration acting on the sensor, but not to the translational acceleration.

The embodiment shown in FIG. 4 differs from the embodiment shown in FIGS. 1 to 3 in which a flow path constriction member is provided by changing the distance between the electrodes and changing the inclination angle or rotation based on the accompanying change in the electrical impedance between the electrodes. It is capable of detecting angular velocity and angular acceleration, and consists of a solid mass 32 disposed in the center 31a of a long tubular container 31 in the longitudinal direction, and a spring that allows displacement in the longitudinal direction. It is supported by the container 31 by a supporting means 33 which is provided with a support means 33 . As the support means 33, other means that allow displacement in the longitudinal direction, such as a support string, can be used. Further, the mass 32 is provided with a center electrode 34, which serves as a movable electrode that moves together with the mass 32, and end electrodes 35 are provided at symmetrical positions on both sides in the longitudinal direction.
The inside is filled with a conductive liquid 36. These central electrode 34 and each end electrode 35, 35 are connected to a detection circuit that detects the electrical impedance between these electrodes.

The mass 32 must be made smaller than the container 31, and the electrode 34 provided on the mass 32 must be connected to the outside of the container 31 by a thin lead wire that can be easily displaced mechanically.

In the sensor having the above configuration, when the mass 32 is tilted due to gravity or rotational external force, the distance between the center electrode 34 and the end electrodes 35, 35 changes, and the electrical impedance between the two electrodes changes accordingly. Since the electric impedance changes, the tilt angle, the angular velocity of rotation, and the angular acceleration are detected.

The embodiment shown in FIG. 5 is a biaxial expansion of the sensor shown in FIG.
A spherical solid mass 42 is disposed in the container 41, and is supported by the container 41 by support means 43 constituted by a spring. As the support means 43, other support means such as a support string can be used. In addition, the central electrode 44 attached to the mass 42 is constructed by stretching the electrode over the entire surface of the mass so that it is not sensitive to twisting of the spring, support string, etc., and uses it as a movable electrode. There is. moreover,
An end electrode 45 is provided at each axial end of the cross-shaped container 41, and the inside of the container 41 is filled with a conductive liquid 46.

This rotation sensor is configured to output changes in electrical impedance between the center electrode 44 and the end electrodes 45, 45 located opposite each other as two sets of differential signals.

In each of the embodiments described above, the pendulum system constituted by the mass and its support means can damp the natural vibration depending on the size, spring stiffness, and viscosity of the conductive liquid.

In the rotation sensor having the above configuration, it has been difficult to control the amount of foreign matter to be injected because it expands, narrows, increases or decreases the current flow path, and it is directly affected by the inner wall properties of the tube and becomes a factor that distorts the characteristics. Since a solid mass supported by a spring or support string is used instead of the air bubbles that were previously used, when the mass is displaced due to tilting or rotational external force, it is not affected by the manufacturing accuracy or properties of the inner wall of the container. Moreover, since the volume of the moving mass remains completely unchanged, it is possible to perform the operation as designed.

In particular, when the mass is supported by a support string, the electrical impedance output corresponds to the inclination with respect to the axis of gravity, and when the mass is supported by a spring, it is not limited to the static inclination angle from the vertical axis. , it can also accommodate dynamic angle changes around the horizontal and vertical axes.

[Effects of the Invention] According to the rotation sensor of the present invention, the following effects can be expected.

(a) When the mass is supported by support strings, 1. The mass is simply made into a rotationally symmetrical body, and the detection characteristics do not depend on the manufacturing accuracy of the inner wall of the pipe, and it is also difficult to deform due to rotation. A sensor can be configured, and by configuring this container in a cross shape, it can be used as a two-dimensional rotation sensor.

2. An electrode can be added to the mass to make it a movable electrode, and the same effect as 1) above can be obtained with a simple configuration.

(b) When the mass is supported by a spring, 3) As a rotation sensor for one axis direction, by changing the above support string to a spring, 1), 2)
It is possible to create a configuration that satisfies the above requirements, and also allows for a configuration that responds to rotational fluctuations around the vertical axis.

4. Measurement sensitivity can be improved by adding a flow channel constricting member that changes the cross-sectional area of the current flow channel to the mass.

5. When two uniaxial rotation sensors are connected in series to form an annular container part, the translational acceleration component (including the gravitational component) is canceled out by taking the differential of their detection outputs. Only the rotational fluctuation component can be acquired.

6 By means of biaxially uniform springs, the above 1) and 2)
Similarly, it can be extended to two-dimensional responsive sensors.

[Brief explanation of drawings]

1 to 5 are sectional views showing different embodiments of the rotation sensor according to the present invention, respectively. 1, 11, 21, 31, 41...container, 1a,
31a, 41a...Central part, 2, 12, 22, 3
2,42...Solid mass, 3,13,23,33,
43...Supporting means, 4, 14, 24, 34, 44
...Central electrode, 5, 15, 25, 35, 45...
... End electrode, 6, 16, 26, 36, 46 ... Conductive liquid, 7, 17, 27 ... Channel constriction member.

Claims (1)

[Scope of Claims] 1. A solid mass is supported at the center in the longitudinal direction of a long tubular container whose interior is filled with a conductive liquid by a support means such as a spring or a support string that allows displacement in the longitudinal direction; A center electrode and an end electrode are provided at the center and both ends in the longitudinal direction of the container, and the mass is
A flow path constricting member is attached that changes the cross-sectional area of the current flow path between the center electrode and the end electrodes by displacement in the longitudinal direction of the mass due to gravity or rotary external force, and the angular velocity of the tilt angle or rotation, based on the change in electrical impedance between
A rotation sensor characterized by being able to detect angular acceleration. 2. A solid mass is supported in the longitudinal center of a long tubular container whose interior is filled with a conductive liquid by a support means such as a spring or a support string that allows displacement in the longitudinal direction, and an electrode is mounted on the mass. In addition, end electrodes are provided at both ends of the container in the longitudinal direction of the container, and displacement of the mass in the longitudinal direction by gravity or rotary external force causes the central electrode and the end electrode to move together with the mass. A rotation sensor characterized in that the distance between the electrodes can be changed, and the tilt angle, the angular velocity of rotation, and the angular acceleration can be detected based on the change in electrical impedance between the central electrode and the end electrode. .