JPH0390830A - Pressure sensor - Google Patents

Abstract

PURPOSE:To realize large area and to detect a pressure position by detecting pressure variation by variation in the quantity of projection light, and thus taking measurements without any influence of electric nor magnetic noises and arranging plural pressure sensors successively in plane. CONSTITUTION:A projector 6 is arranged outside a light input part 4 and a photodetector 7 is arranged outside a light output part 5, and the light emitted by the projector 6 passes through the light input part 4, a transparent elastic member 2, and the light output part 5 to enter the paired photodetector 7. Then pressure is applied to the top plane of a contact part 1 in the moving direction of the contact part 1, whose projection surface presses the elastic material 2. Further, the projection light 9 from the projector 6 passes through the elastic material 2 from the light input part 4, but the quantity of light reaching the light output part 5 is reduced by the density variation of the elastic material 2 and the projection surface of the contact part 1, so that the quantity of photodetection of the photodetector 7 decreases.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to pressure sensors.

[Conventional technology]

Conventional pressure sensors, such as resistance output type and capacitance output type, detect changes in resistance and capacitance using electrical quantities.

[Problem to be solved by the invention]

The conventional pressure sensor described above is configured to detect pressure using electrical quantities such as resistance changes, capacitance changes, voltage changes, magnetic changes, etc., so it is electrical.

In addition to malfunctions due to magnetic noise, the structure is designed to detect changes in point positions, so it is difficult to increase the area and it is not easy to handle.

An object of the present invention is to provide a pressure sensor that solves the above problems.

[Means to solve the problem]

The pressure sensor of the present invention has a cubic box shape with the - side as an opening surface, and has a surface substantially parallel to the opening surface near the bottom surface of each of two sets of mutually opposing surfaces that touch one side of the opening surface. A container made of an opaque material and having a light input part and a light output part forming a transparent part for inputting and outputting light beams, and preventing incident light from other than the transparent part; a transparent elastic material made of a pressure-receiving elastic element that restores its original state when the pressure is reduced; a substantially columnar contact portion that fits approximately inside the container and is inserted from the opening surface to press the transparent elastic material against the bottom surface of the container; a floodlight that emits light toward an optical output section facing the input section;
It has a light receiver that receives the light emitted by the light projector via the light output section and outputs the amount of the received light.

[Effect]

In the pressure sensor using the above-mentioned means, when the contact part receives pressure in a direction substantially perpendicular to the opening surface, the transparent elastic material formed by the pressure-receiving elastic element receives pressure and increases its density, and the light passing through the transparent elastic material from the projector increases. The light receiver outputs changes in pressure depending on changes in the amount of light received.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing an example in which pressure is applied to the contact portion of FIG. 1,
3 is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 4 is an external perspective view showing an example of the pressure sensor shown in FIG. 1 with only one pressure sensor and omitting the light emitter and light receiver.

First, explanation will be given with reference to FIG. 1 and FIG. 4 together.

As shown in FIG. 4, the main part of the pressure sensor shown in this figure is that a transparent elastic material 2 is housed in a container 3, and a contact part 1 slides onto the inner surface of the container 3 from the upper opening surface of the container 3. death,
The internal transparent elastic material 2 is compressed or released. Contact part 1
has a substantially rectangular parallelepiped shape that fits inside the container 3, the top surface is a plane substantially parallel to the opening surface of the container 3, and the bottom surface is, for example, semispherical, making it easier to press the transparent elastic material 2 inside. The transparent elastic material 2 contracts when pressure is applied and restores its original state when the pressure is reduced, so that changes in the pressing force can be obtained by changes in the amount of light. The container 3 is a box made of an opaque material that blocks unnecessary light from the outside and has an opening surface at the top of a cube. A light input section 4 and a light output section 5 are formed on each of the two opposing surfaces at a position where light passes through a surface substantially parallel to the bottom surface, that is, near the bottom surface and on a surface substantially parallel to the bottom surface. A light projector 6 is provided outside the light input section 4, and a light receiver 7 is provided outside the light output section 5. The light emitted from the light projector 6 is transmitted to the light input section 4. Transparent elastic material 2 and light output section 5
and enters the photoreceiver 7 that becomes a pair.

Two sets of floodlights for one pressure sensor6. A light receiver 7 can be provided, and the two projected beams 9 are substantially perpendicular to each other, as shown in FIG.

Regarding pressure detection, as shown in Fig. 2, the contact part 1
Pressure is applied in the moving direction of the contact portion 1 on the upper plane of the contact portion 1, and the contact surface 8 presses the transparent elastic material 2 of the contact portion 1.

Projected light 9 from the projector 6 is transmitted from the light input section 4 to the transparent elastic material 2.
However, due to the change in the density of the transparent elastic material 2 and the text on the contact portion 1, the amount of light reaching the light output portion 5 is reduced, and the amount of light received by the light receiver 7 is reduced.

Next, Fig. 5 is an external perspective view showing an example in which the main parts of four pressure sensors are arranged on the same plane, and Fig. 6 is a planar arrangement explanatory diagram showing an example in which 16 pressure sensors are arranged in a matrix. It is.

This will be explained with reference to FIGS. 5 and 6.

That is, the contact portion 1 of the pressure sensor is on the same plane,
The light input section 4 on one side serves as the light output section on the opposite surface of the container (the back surface in FIG. 5), and the light output section 5, which is also shown in FIG. 5, serves as the light input section on the other side (not shown). and each form a pair. That is, as shown in FIG. 6, the emitters XtS to X43 (6) on the
(7), and the floodlight y,, ~y4s (6
) forms projection optical axes in a matrix in the light receivers Y + n to Y 4 R (7).

〔Effect of the invention〕

As explained above, the present invention has a configuration in which pressure changes are detected by changes in the amount of projected light.
This can be done without affecting atmospheric noise, and by arranging multiple pieces side by side on a plane, it is possible to increase the area.
It also has the advantage of being able to detect pressure positions.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing an example in which pressure is applied to the contact portion of FIG. 1,
Figure 3 is a sectional view taken along the line A-A in Figure 2, Figure 4 is an external perspective view showing an example of Figure 1 in which only one pressure sensor is used and the emitter and receiver are omitted, and Figure 5 is the same as in Figure 1. FIG. 6 is an external perspective view showing an example of four main parts of pressure sensors, and FIG. 6 is an explanatory plan layout diagram showing an example of 16 pressure sensors arranged in a matrix. 1...Contact part, 2...Transparent elastic material, 3
...Container, 4...Light input section, 5...
...Light output unit, 6...Light emitter, 7...
・Photoreceiver.

Claims (1)

[Claims] A transparent box that has a cubic box shape with one side as an opening surface, and allows light to be input and output on a surface approximately parallel to the opening surface near the bottom of each of two sets of mutually opposing surfaces that touch this opening surface on one side. A container made of an opaque material that has a light input part and a light output part forming a part and prevents incident light from other than the transparent part, and a pressure-receiving elastic element that is housed inside the container and contracts due to pressure, but returns to its original state when the pressure is reduced. a transparent elastic material according to the present invention; a substantially columnar contact portion that fits approximately inside the container and is inserted from the opening surface to press the transparent elastic material against the bottom surface of the container; and a light output portion facing the light input portion. A pressure sensor comprising: a light projector that emits light toward the projector; and a light receiver that receives the light emitted by the projector via the light output section and outputs the amount of the received light.