JP3071768U - Non-contact potentiometer - Google Patents

Abstract

(57) [Problem] To provide a stable high output in a non-contact potentiometer. SOLUTION: In a non-contact potentiometer in which the inductance of coils 10a and 10b on a coil substrate 10 is changed by rotating a detection plate 13 by an operation shaft 9 and the change is taken out as a signal, the detection plate 13 is provided. In this case, two coils are provided above and below the coil substrate 10.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a non-contact potentiometer used for various machine tools, measuring devices, control devices, and the like.

[0002]

[Prior art]

 Conventional non-contact potentiometers generally put into practical use include a coil provided on a substrate inside a case, and a detection plate provided opposite to the coil and rotated by an operation shaft. By rotating the coil, the inductance of the coil is changed, and the change is extracted as a signal.

[0003]

[Problems to be solved by the invention]

 This non-contact potentiometer is required to have stable output and high output, but the conventional non-contact potentiometer has a structure in which one detection plate is provided facing the coil. As a result, output fluctuations are likely to occur due to the effects of temperature changes and backlash of the operating axis, and high output cannot be expected.

SUMMARY OF THE INVENTION [0004] In view of the above, an object of the present invention is to provide a non-contact potentiometer capable of obtaining a stable and high output with a simple structure.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the non-contact potentiometer of the present invention includes a case configured by fitting a plurality of divided case structures by fitting, and a rotatably supported shaft facing the inside and outside of the case. An operating shaft, a coil provided on a substrate inside the case, and two detection plates attached to the operating shaft so as to face the coil with the substrate interposed therebetween and rotated integrally with the operating shaft. By rotating the two detection plates by the operation shaft, the inductance of the coil is changed, and the change is extracted as a signal.

[0006] In the non-contact potentiometer of the present invention configured as described above, since two detection plates facing the coil are provided with the substrate interposed therebetween, it is possible to obtain a stable high output with little output fluctuation. Can be. Furthermore, since this non-contact potentiometer has a structure in which a case is fitted and assembled, the assembling work is simple and effective for cost reduction.

[0007]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 show a first embodiment of a non-contact potentiometer according to the present invention. FIG. 1 is a perspective view of the appearance, FIG. 2 is an exploded perspective view, and FIG. 3 is a longitudinal sectional view.

In FIG. 1, 1 is a non-contact potentiometer according to the present invention as a whole, 2 is a case (housing), and this case 2 is composed of an upper case assembly 2A and a lower case assembly 2B divided into two parts. Be composed.

The upper case structure 2A and the lower case structure 2B are both made of plastic (resin), and are assembled by fitting them in an engaging manner.

[0010] That is, a pair of engaging pieces 3 protrude from the lower case structure 2B, and an engaging convex portion 3a is formed on the inner side of the distal end thereof. Is provided with an engagement recess 4.

In a state where the upper case structure 2A and the lower case structure 2B are combined, the engaging projection 3a of the engaging piece 3 of the lower case structure 2B engages with the engaging concave portion 4 of the upper case structure 2A. Thus, the upper case structure 2A and the lower case structure 2B are integrally fixed and assembled.

Reference numeral 5 denotes a terminal plate from which the terminal 12 protrudes. The terminal plate 5 is provided between the concave portion 6a of the upper case structure 2A and the concave portion 6b of the lower case structure 2B so as to partially sandwich the case 4. Make up.

A bearing boss 7 is provided at the center of the upper case structure 2 A of the case 2 assembled in this manner, and a bearing 8 is mounted inside the bearing boss 7. 9 is rotatably supported facing the inside and the outside of the case.

Inside the case 2, the coil board 10 and the circuit board 11 are fixed. A pair of coils 10 a and 10 b are provided on the coil substrate 10, and the coils 10 a and 10 b are formed in a winding shape that is curved in an arc around the operation shaft 9. The coils 10a and 10b may be laminated and wound to be fixed to the circuit board 10, or may be formed by laminating the circuit board 10 by printing, vapor deposition, sputtering, or the like. .

On the other hand, on the circuit board 11, a high-frequency oscillation circuit for applying high frequency to the coils 10a and 10b and a detection circuit for detecting a change in inductance of the coils 10a and 10b are provided. The circuit is connected to the outside via a terminal 12.

At the lower end of the operation shaft 9 facing the inside of the case 2, two upper and lower detection plates 13 are attached in parallel. The detection plate 13 is disposed so as to face the coils 10a and 10b with a small gap with the circuit board 10 interposed therebetween, and is rotated integrally with the operation shaft 9.

The detection plate 13 is a metal plate having good conductivity or a non-conductive metal plate coated with a metal having good conductivity by plating or the like, and has a semicircular sector shape. The structure is such that the operation shaft 9 rotates so as to alternately face the coils 10a and 10b.

In the contactless potentiometer of the present embodiment configured as described above, when high frequency is applied to the coils 10 a and 10 b from the high frequency oscillation circuit on the circuit board 11, an eddy current is generated in the detection plate 13, and in that state, When the operation shaft 9 is rotated to rotate the detection plate 13 integrally therewith, the area of the detection plate 13 facing the coils 10a and 10b changes, so that the eddy current value changes and the inductance of the coils 10a and 10b decreases. Change. Then, the change is detected by the detection circuit on the circuit board 11 and is taken out from the terminal 12 as an output signal.

Here, in the non-contact potentiometer according to the present invention, in particular, two detection plates 13 facing the coils 10a and 10b are provided vertically above and below the coil substrate 10, so that the temperature change and the operation axis can be reduced. The output fluctuation due to the backlash of No. 9 is small and a high output can be obtained.

Further, in this non-contact type potentiometer, the case 2 is made of inexpensive plastic, and the case 2 has a structure that can be assembled by engaging-type fitting, so that a fixing member such as a screw is not used at the time of manufacture. Because it can be easily assembled with one touch, it can be manufactured at low cost.

4 to 6 show a second embodiment of the non-contact potentiometer according to the present invention. FIG. 4 is a perspective view of the appearance, FIG. 5 is an exploded perspective view, and FIG. is there.

The difference between the second embodiment and the first embodiment is the structure of the case 2. That is, in the second embodiment, the case 2 is composed of three case structures, an upper case structure 2A, a lower case structure 2B, and an intermediate case structure 2C therebetween, which are assembled by fitting. is there.

The upper case structure 2A, the lower case structure 2B, and the middle case structure 2C are all made of metal, and the upper case structure 2A and the middle case structure 2C are screw-fitted and combined. Has become.

That is, screw grooves 15 and 16 are formed on the outer periphery of the upper case structure 2A and the inner periphery of the middle case structure 2C, respectively. When the upper case structure 2A and the middle case structure 2C are combined, the screw grooves are formed. Screw 15 and 16 into each other and rotate them to fit each other.

Further, the lower case structure 2B and the middle case structure 2C have a structure in which they are fitted by press-fitting and combined.

That is, the lower case structure 2B and the middle case structure 2C are combined by fitting the step 17 on the outer periphery of the lower case structure 2B into the step 18 on the inner periphery of the middle case structure 2C. By setting the outer diameter of the step 17 of the case structure 2B to be slightly larger than the inner diameter of the step 18 of the middle case 2C, the lower case 2B can be pressed into the middle case 2C. It is fitted into and fixed.

The internal structure of the non-contact potentiometer according to the second embodiment, in which the case 2 is assembled as described above, has almost the same configuration as that of the first embodiment described above, and a description thereof will be omitted. However, the contactless potentiometer of the second embodiment has a structure in which the lead wire 19 is drawn out from the circuit board 11 through the lower case assembly 2B instead of the terminal 12 of the first embodiment. It has become.

In the contactless potentiometer of the second embodiment configured as described above, although the material cost is slightly increased because the case 2 is made of metal, the case 2 is fitted by a screw type and a press-fit type. Since it is a structure that can be assembled, it can be assembled with a simple operation at the time of manufacturing, which is effective in reducing costs as a whole.

Although the embodiment of the non-contact potentiometer according to the present invention has been described above, it is needless to say that the present invention is not limited to the above-described configuration, but can adopt various other embodiments.

[0030]

[Effect of the invention]

 As is clear from the above description, in the non-contact potentiometer according to the present invention, since two detection plates facing the coil are provided with the substrate interposed therebetween, a stable high output can be obtained and a high performance can be obtained. Products can be provided. Furthermore, since this non-contact potentiometer has a structure that is assembled by fitting a case, it can be easily assembled without using fixing members such as screws at the time of manufacture, which is effective for cost reduction and product price reduction. Can greatly contribute to

[Brief description of the drawings]

FIG. 1 shows a first example of a non-contact potentiometer according to the present invention.
It is a perspective view which shows the Example of FIG.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is a longitudinal sectional view of the same.

FIG. 4 shows a second example of the non-contact potentiometer according to the present invention.
It is a perspective view which shows the Example of FIG.

FIG. 5 is an exploded perspective view of the same.

FIG. 6 is a longitudinal sectional view of the same.

[Explanation of symbols]

1 ‥‥ non-contact potentiometer, 2 ‥‥ case, 2A
{Upper case structure, 2B} Lower case structure, 2C} Middle case structure, 9} Operation axis, 10} Coil board, 10
a, 10b coil, 13 ° detection plate

Claims (2)

[Utility model registration claims] 1. A case constituted by assembling a plurality of divided case structures by fitting, an operation shaft rotatably supported facing the inside and outside of the case, and a board inside the case. And two detection plates attached to the operation shaft so as to face the coil with the substrate interposed therebetween, and two detection plates rotated integrally with the operation shaft. A non-contact potentiometer wherein the inductance of the coil is changed by rotating two detection plates, and the change is extracted as a signal. 2. The non-contact potentiometer according to claim 1, wherein the case has a structure assembled by engaging, screwing or press-fitting.