JPS61212771A - Rotation sensor - Google Patents

Abstract

PURPOSE:To enable the detection of dynamic value of rotation involving the fluidization of a liquid, by a method wherein a conductive liquid is sealed between electrodes inside a circular container to give an electric resistance or impedance thereto and changes in the electric resistance or impedance between the electrodes are determined when the liquid is fluidized by a rotary external force with the application of a voltage between the electrodes. CONSTITUTION:A conductive liquid 4 is sealed between two pairs of electrodes 3a and 3b and 3b provided inside a circular container 2 to give electric resistance or impedance. A rotary external force is made to work on the container 2 to fluidize the liquid 4 to the container 2 relatively. While a DC and AC voltage is applied between opposed electrodes 3a and 3a and 3b and 3b of a rotation sensor 1, a rotary external force is provided to the sensor 1 about a vertical shaft L thereof, which causes a relative fluidization between the wall of the container 2 and the liquid 4. With the fluidization, a difference arisens among positive and negative ions of the liquid 4 in the arrival at the opposed electrodes. This causes a change in the resistance, electrostatic capacitance and inductance thereby enabling the dynamic value of rotation involving the fluidization of the liquid 4 by detecting the changes.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotation sensor used to detect rotational mechanical quantities.

[Prior Art] The potential difference between the counter electrodes of an ionic conductor is the electrical resistance R1 between them, which is expressed by the following formula: It is well known that ρ depends on specific resistance.

The application of this law to industry is wide-ranging, for example in the field of electrochemistry, such as electrolysis, plating, powder separation, dust collection, electrostatic painting, and batteries, but the use of the first law is , in the above equation, where a, l, and ρ are constant, and in an environment where the ionic conductor has a steady flow in one direction, this is done by focusing on the preparation efficiency, power efficiency, etc.

However, from a different perspective, when the flow velocity of the ionic conductor dynamically changes, the specific resistance ρ changes correspondingly, and therefore the electrical resistance R changes, and furthermore, the ionic conductor refluxes. It is inferred that the ffi resistance R changes also due to this.

In addition, it is generally known that a resistor has an electrostatic capacitance 1c and an inductance L depending on its constituent members and shape, and also has an impedance Z as a correlation between these and the above resistance R. Electrical resistance R in equation (1) is replaced by impedance Z.

In view of the above, the present inventor sealed an ionic conductor in an annular container provided with a counter electrode, and when a rotational mechanical quantity to be measured acts on the ionic conductor, the ionic conductor in the annular container Reflux occurs, causing a slight difference in the arrival of the positive and negative ions to the counter electrode, so we came up with the idea that the above-mentioned rotational dynamic quantity can be detected from the accompanying change in differential potential over time.Based on this, we developed the present invention. This is what led to the eggplant.

[Problems to be Solved by the Invention] An object of the present invention is to obtain a rotation sensor having an in-cylinder configuration based on the above-mentioned principle for detecting rotational mechanical quantities such as five rotational angular velocities or rotational angular accelerations.

[Means for Solving the Problems] In order to achieve the above object, the rotation sensor of the present invention includes a plurality of counter electrodes provided inside an annular container and an electric resistance or impedance provided between the electrodes. A conductive liquid is sealed, a voltage is applied between the counter electrodes as appropriate, and when the conductive liquid flows relative to the container due to a one-turn external force, the liquid changes due to changes in electrical resistance or impedance between the counter electrodes. It is characterized by being able to detect rotational mechanical quantities involved in flow.

[Function] In the rotation sensor configured as described above, when a rotational force is applied from the outside, the conductive liquid inside the container flows relative to the container wall, and this flow reduces the direct current resistance or static electricity between the electrodes. Impedance changes due to capacitance, inductance, etc. Therefore, if a DC voltage or an alternating voltage is applied between the counter electrodes in advance, changes in DC resistance or impedance between the electrodes can be detected using another counter electrode, etc. placed oppositely between the counter electrodes. , the rotational dynamic quantity can be measured from these changes 1d.

[Effects of the Invention] The rotation sensor of the present invention, which resembles a sleeve, has a simple structure in which the electrode and the conductive liquid are housed in an annular container, so it can be extremely miniaturized and cost-effective. In addition, without changing the basic configuration of the sensor itself, it is possible to adjust the material of the container and conductive liquid, the type of AC/DC power source used, the magnitude of the applied voltage, the resistance/impedance, etc. according to the object to be measured and detected. Various signal processing formats can be used by considering how to assemble a bridge circuit to detect the signal and the calibration of the detection (q).

Therefore, it can be effectively used, for example, as a sensor for detecting the rotation and turning gutter of a robot's hand or arm, a sensor for the rotational speed of a human hand or arm, a rotation sensor for a large moving part of a machine, etc. I can do it.

[Embodiment] The embodiment of the present invention shown in FIG. Inside the annularly configured container 2, two pairs of needle-shaped or mesh-shaped counter electrodes 3a, 3a made of any material such as carbon or platinum are provided.
and 3b, 3b are enclosed and provided oppositely, and the counter electrode 3a is
, 3a and 3b, a conductive liquid 4 that gives an electrical resistance R or impedance Z is sealed between 3b, and a lead wire 5a connected to the counter electrodes 3a, 3a and 3b, 3b.
, 5a, 5b, and 5b are led out of the container 2 in a sealed state. Therefore, the conductive liquid 4 is configured to flow relative to the container 2 when a rotational external force is applied to the container 2 . Note that the shape, number, and location of the counter electrodes provided in the container 2 are not limited to those described above.

As the conductive liquid 4, any electrolyte liquid, powder mixture liquid, etc. can be used, and specifically, for example, various electrolytic solutions such as a sodium chloride aqueous solution, colloidal liquids such as soap solution, or dielectric liquids. A powder mixture containing powder, piezoelectric powder, etc. can be used.

Thus, the counter electrodes 3a, 3a and 3b of the sensor 1.

3b through the lead wires 5a, 5a, 5b, 5b in advance, and when applying a rotary external force around the vertical axis to the sensor 1 in that state, the container wall of the sensor l and the inside A relative flow occurs between the conductive liquid 4 and the conductive liquid 4, and due to the flow, a difference occurs in the degree to which positive and negative ions in the liquid 4 reach the counter electrode.

The resistance R1 capacitance C or inductance L changes, and as a result, the resistance R or impedance Z of the sensor as a whole changes.

All of these depend on the flow rate, flow area, etc. of the conductive liquid in the circular mound-shaped container, so the angular velocity involved,
By associating an external mechanical quantity such as angular acceleration with liquid motion and the amount of change in impedance obtained through an appropriate detection circuit, the above resistance R or impedance Z can be determined.
By detecting changes in , it is possible to measure the rotational force involved in the flow of the conductive liquid.

FIG. 2 shows an example of a detection circuit connected to the rotation sensor to detect rotational mechanical quantities.
A standard alternating voltage is applied between the pair of electrodes 3a, 3a, and in that state, a rotating external force is applied to convert the potential difference between the other counter electrodes 3b, 3b caused by the rotation of the conductive liquid 4 into a differential amplifier. In order to extract a minute differential potential change based on the difference in the degree of arrival of positive and negative ions to each electrode, which is detected by the output signal 12 and further superimposed on the output signal, the amplitude phase adjustment circuit 14 is used.
The difference between the reference voltage whose amplitude and phase have been adjusted by the differential amplifier 13
The rotational dynamic quantity is detected based on the output signal of the amplifier 13, and the amplitude of the output signal of the amplifier 13 increases as the flow rate of the conductive liquid 4 increases. However, the phase is reversed as the direction of flow of the conductive liquid 4 is normal or reverse.

In addition to the above-described detection circuits, detection circuits based on various signal processing methods can be considered.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a circuit configuration diagram showing an example of a signal detection circuit connected thereto. 2nd grade container, 3,3a/◆electrode, 4th grade/conductive liquid. Designated Agent Director, Product Science Research Institute, Agency of Industrial Science and Technology, Tsukasa Takahashi b No. 28

Claims (1)

[Claims] 1. A plurality of counter electrodes are provided inside the annular container, and a conductive liquid that provides electrical resistance or impedance is sealed between the electrodes, and a voltage is applied between the counter electrodes as appropriate to generate a rotary external force. A rotation sensor characterized in that, when the conductive liquid flows relative to the container, a rotational mechanical quantity involved in the liquid flow can be detected by a change in electrical resistance or impedance between the counter electrodes.