KR100834416B1 - Rotating angle detection device used capacitive change and method - Google Patents

Abstract

A rotating angle detection device and a method using capacitance change are provided to reduce a production cost by not requiring a slit hole on a rotating plate and to secure high resolving power of angle detection by obtaining a linear rotating angle conversion value of capacitance. In a rotating angle detection device using capacitance change, a stator(20) has two conductor plates(21,22) of the fixed side. A rotor(30) is relatively rotated for the stator. A conductor plate(31) of the rotating side repeatedly passes over the upsides of the conductor plates of the fixed side in different variable areas whenever the conductor plate rotates one time. Capacitance digital converters are electrically connected to the conductor plates of the fixed side and the conductor plate of the rotating side to convert an analog value of different capacitances into the digital angle.

Description

Rotating angle detection device using capacitive change and its method {Rotating angle detection device used capacitive change and method}

The following drawings, which are attached in this specification, illustrate preferred embodiments of the present invention, and together with the detailed description of the present invention, serve to further understand the technical spirit of the present invention. It should not be construed as limited to.

1 is an exploded view of a stator and a rotor applied to the first embodiment of the present invention.

Figure 2 is an assembled state of the stator and the rotor applied to the first embodiment of the present invention.

3 is a cross-sectional view taken along line A-A of FIG.

4 is a development view of the inner surface of the fixed-side conductor plate applied to the first embodiment of the present invention.

5 is a developed view of a rotating side conductor plate applied to the first embodiment of the present invention.

6 is a block diagram of a rotation angle detection device using a change in capacitance according to a second embodiment of the present invention.

7 is a planar configuration diagram of a fixed side conductor plate and a rotating side conductor plate applied to the second embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

20: stator

21,22: fixed side conductor plate

30: rotor

31: rotating side conductor plate

The present invention relates to a device for measuring the rotation angle of a rotating object, in particular a rotation angle detection device and method for detecting the rotation angle by using a change in the ratio of the capacitance between the conductor plates intersect with the rotation. It is about.

Conventionally, in order to measure the rotation angle of the rotating object, a rotating plate having slit holes at regular intervals, a light emitting element disposed on one side of the rotating plate, and a light signal disposed on the other side of the rotating plate and passing through the slit hole It mainly used a mechanical encoder composed of a light receiving element.

However, in the case of the mechanical encoder method, the slit hole must be configured small or the slit holes are densely arranged to increase the resolution of the angle. However, there is a limitation in physically forming a slit hole or arranging the slit holes closely at equal intervals, so that it is difficult to implement a small slit hole, thereby limiting the resolution of the rotation angle.

In addition, such a mechanical encoder has a relatively expensive manufacturing cost.

Therefore, the present invention was created in view of the above-mentioned circumstances, and it is possible to increase the resolution of the rotation angle by using two capacitance ratio changes, and to realize the rotation angle using the capacitance change that can be manufactured at low cost. It is an object of the present invention to provide a detection device and a method thereof.

Specific means of the present invention for achieving the above object,

In the rotation angle detection device,

A stator having two fixed side conductor plates;

And a rotor provided with a rotation side conductor plate that rotates relative to the stator and repeatedly overlaps the fixed side conductor plate with different change areas at the same time every one revolution.

Also according to the invention,

And a capacitance digital converter electrically connected to the fixed side conductor plate to convert analog values of the different capacitances into digital angles.

Also according to the invention,

The two fixed side conductor plates are each configured in a right triangular form or in a taegeuk form.

Also according to the invention,

A dielectric is further included between the fixed side conductor plate and the rotating side conductor plate to increase the dielectric constant.

Also according to the invention,

An insulator and a shield are respectively formed on the rear surfaces of the fixed side conductor plate and the rotating side conductor plate.

In addition, the rotation angle detection method according to the present invention,

Two fixed-side conductor plates provided on the entire plane or inner circumferential surface thereof and a rotation-side conductor plate rotatably disposed on the fixed-side conductor plate with a predetermined area therebetween;

Connecting the rotating side conductor plate to a rotating body;

The rotational conductor plate is rotated to convert the respective capacitances C1 and C2 generated between the two fixed-side conductor plates to digital values using a capacitive digital converter and then to a correction capacitance ratio C1. And converting the rotation angle to a rotation angle corresponding to / (C1 + C2)).

First, the present invention is a concept of applying a capacitive sensor method, and calculates the ratio of two capacitive capacities for high resolution to detect a rotation angle (0 ° to 360 °) by linear angle conversion. do.

That is, in the present invention, the rotational conductor plate connected to the rotational shaft passes two fixed-side conductor plates at the same time in different areas so that the ratio of capacitance generated according to the changed area of the fixed-side conductor plate is 360 °. It is configured to correspond to.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 to 3, the rotation angle detection device according to the present invention is composed of a stator 20, and a rotor 30 that rotates relative to the stator 20.

In the first embodiment, the stator 20 has a cylindrical shape and the rotor 30 has a circular cross section and is inserted into the stator 20 to rotate. At this time, the rotor 30 has a rotating shaft (30a) for receiving a rotational force from a rotating body (not shown).

The stator 20 is provided with two fixed side conductor plates 21 and 22 divided on the inner circumferential surface thereof.

In the present embodiment, the two fixed side conductor plates 21 and 22 have a right triangular shape with sides of the same slope as in the development of FIG. 4.

At this time, a shield 24 is formed on the rear surface of the fixed side conductor plates 21 and 22 with the insulator 23 interposed therebetween. In this case, the shield 24 is installed to prevent parasitic capacitance caused by an armature or a magnetic field flowing from the outside.

The rotor 30 is provided on one outer circumferential surface and is provided with a rotation side conductor plate 31 which is moved on the two fixed side conductor plates 21 and 22 at each rotation and overlaps with different change areas. have.

At this time, the rotation side conductor plate 31 is smaller than the length L of the fixed side conductor plates 21 and 22 and is configured to be equal to the width H of the fixed side conductor plates 21 and 22.

Moreover, the insulator and the shield 33 are each comprised in the back surface of the said rotation side conductor plate 31 through the insulator 32. At this time, the shield 23 is installed to prevent the parasitic capacitance of the armature or magnetic field flowing from the outside.

On the other hand, the present invention is the capacitance digital converter for converting the analog values of the different capacitance (C1, C2) generated between the fixed side conductor plate (21, 22) and the rotating side conductor plate 31 to a digital angle ( 40a and 40b are electrically connected to each other.

In the rotation angle detecting device of the first embodiment configured as described above, a rotating body (not shown) is connected to the rotating shaft 30a of the rotor 30.

When the rotor 30 rotates in this state, the rotation side conductor plate 31 passes over two fixed side conductor plates 21 and 22 with different areas. Therefore, the overlapping area of the rotating conductor plate 31 and the fixed conductor plates 21 and 22 is changed for each revolution of the rotor 30.

As a result, the capacitances C1 and C2 are changed between the fixed side conductor plates 21 and 22 for each rotation angle at which the rotation side conductor plate 31 is located.

That is, as shown in the experimental results in Table 1 below, the width of the rotating conductor plate 31 is 10 mm, and the width of the fixed conductor plates 21 and 22 is 31,4 mm (circumference of a circle of 10 mm in diameter). When the length is 5mm, it can be seen that the capacitances C1 and C2 according to the moving position of the rotor 30 are changed in inverse proportion to each other.

In addition, when plotting the ratio of the resolution C1 / (C1 + C2) using the values of the capacitance (C1, C2) it can be seen that shown in Table 2 below.

Accordingly, each capacitance is converted into a digital value by capacitance digital converters 40a and 40b electrically connected to the fixed-side conductor plates 21 and 22 and the rotating-side conductor plate 31, from which C1 / ( The ratio C1 + C2) is obtained and the corresponding rotation angle (0 ° to 360 °) is converted.

)을 높여 전기용량을 크게 하여 분해능을 높이기 위한 유전체가 더 설치될 수 있다.Meanwhile, the dielectric constant (between the fixed side conductor plates 21 and 22 and the rotating side conductor plate 31)

), A dielectric may be installed to increase the capacitance to increase the resolution.

)이 높은 유전체를 사용하면 각도 분해능을 더욱 증진시킬 수 있다.In general, the capacitance (C) is defined as follows, so in the present invention, the area (A) of the conductor plate is increased, the thickness (d) of the dielectric is decreased, or the dielectric constant (

Higher dielectrics can further enhance angular resolution.

는 자유공간의 유전율이다.here,

Is the permittivity of free space.

On the other hand, the present invention is a second embodiment of the modification, the stator 20 and the rotor 30, as shown in Figs. 6 and 7 is formed in a disc shape, wherein the two fixed side conductor plate 21, 22) is characterized in that the deformation of the right triangle is configured in the form of a spiral.

Since the operation thereof is the same as in the first embodiment, detailed description thereof will be omitted.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto, and the technical idea of the present invention and the following by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

As described above, according to the rotation angle detection apparatus using the capacitance change of the present invention, since it is not necessary to form a slit hole in the rotating plate, it can be configured small and the manufacturing cost can be implemented at low cost. In addition, since a linear rotation angle conversion value is obtained as a ratio of capacitance, it has an advantage of obtaining high resolution of angle detection.

Claims (7)

In the rotation angle detection device, A stator 20 having two fixed side conductor plates 21 and 22; Rotor provided with a rotation side conductor plate 31 which rotates relative to the stator 20 and repeatedly passes over the fixed side conductor plates 21 and 22 with different change areas at each rotation ( Rotation angle detection device using a change in capacitance characterized in that it comprises a 30). The method of claim 1, And further comprising capacitance digital converters 40a and 40b electrically connected to the fixed side conductor plates 21 and 22 and the rotary side conductor plate 31 to convert the analog values of the different capacitances into digital angles. Rotation angle detection device using a capacitance change, characterized in that. The method of claim 1, The two fixed-side conductor plates (21, 22) are rotated angle detection device using a capacitance change, characterized in that the configuration of the right-hand triangular shape in order to maximize the area ratio according to the position. The method of claim 1, The two fixed-side conductor plates (21, 22) is a rotation angle detection device using a capacitance change, characterized in that the deformation of the right triangle is formed in a spiral form. The method of claim 1, Rotation angle detecting device using a capacitance change characterized in that the dielectric is further configured to increase the dielectric constant between the fixed side conductor plate (21, 22) and the rotating side conductor plate (31) . The method of claim 1, An insulator (23) and a shield (24) are formed on the rear surfaces of the fixed side conductor plates (21, 22) and the rotating side conductor plates (31), respectively. In the rotation angle detection method, Two fixed-side conductor plates provided on the entire surface or the inner circumferential surface thereof and a rotating-side conductor plate facing each other and rotatably disposed with a predetermined overlapping area; Connecting the rotating side conductor plate to a rotating body; The rotational conductor plate is rotated to convert the respective capacitances C1 and C2 generated between the two fixed-side conductor plates to digital values using a capacitive digital converter and then to a correction capacitance ratio C1. / (C1 + C2)) to the rotation angle corresponding to the rotation angle detection method comprising the step of detecting the rotation angle, characterized in that the rotation angle detection method.

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