JPH02165524A - Contactless switch - Google Patents

Abstract

PURPOSE:To make it possible to make the contactless switch compact and also to lengthen the operation stroke of a moveable body by rotating and displacing a shielder by means of forcing of a movable body disposed along the axis of the tubular main body of the switch, thereby varying the amount of transmitted light. CONSTITUTION:The contactless switch has a moveable body 5 fitted into the main body of the switch 1 in such a manner as being moveable in its axial direction, means for providing recovering forces to the moveable body 5, a sectorial concave mirror 11 disposed on the axis of the main body 1 of the switch so as to reflect light from a light-emitting element 10, and a sectorial slit 14 for transmitting light reflected by the concave mirror 11 to the light- emitting element. Displacement of the moveable body 5 being forced is converted into rotary displacement of a shielder 13 and the amount of transmitted light of the slit 14 is converted to linear according to displacement of the moveable body 5 forced. Miniaturization can thus be achieved, and that with a long stroke is readily available, and in addition, setting of traveling points is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a non-contact switch using light.

<Prior Art and Problems> Conventionally, as this type of switch, as shown in FIG.
3 are arranged facing each other in the left and right direction, and the pixel elements 102,
A plunger 104 having a push-in operation part 104a is positioned between 103 and on the earthen wall side of the switch body 101 so as to be movable up and down, and is elastically supported by a return spring 105. There is one in which a vertically installed tip plate 10B opens and closes the optical path from the light emitting dome 102, thereby controlling the switch output.

However, in the above conventional device, the light emitting element 102 and the light receiving element 103 are arranged in a direction orthogonal to the displacement direction of the plunger 104 provided with the tip plate 10B, so that the outside of the switch body 101 in the orthogonal direction is There is a drawback that the diameter dimension becomes large, and since the optical path from the light emitting element 102 is opened and closed by the mustard tip plate 106 in the orthogonal direction, a long stroke cannot be expected, and furthermore, the distance between the facing elements of the light emitting element 102 and the light receiving element 103 is reduced. If it is not set strictly, there is a problem that it is difficult to accurately determine the operating point.

<Object of the Invention> This invention was made in order to solve the problems of the above-mentioned conventional ones, and provides a non-contact switch that can be made smaller, has a straight stroke, and can easily set the operating point. The aim is to provide the following.

<Structure and Effects of the Invention> A non-contact switch according to the present invention has an operating portion protruding from one end in the axial direction of a cylindrical switch body, and a movable body fitted into the switch body so as to be able to move axially. , means provided on the switch body to apply a restoring force to the movable body;
A fan-shaped concave mirror is arranged on the axis of the switch body and reflects light from the light emitting element, and a fan-shaped slit is arranged on the same axis as the concave mirror to transmit the reflected light from the concave mirror to the light receiving element. A rotatably arranged shield light body, and a light shield rotation unit that converts the pushing displacement of the movable body into a rotational displacement of the light shielding body and linearly changes the amount of light transmitted through the slit according to the push amount. The displacement means is A(t#).

According to this invention, since the luminous body is rotationally displaced by pushing the movable body disposed along the axis of the cylindrical switch body to change the amount of transmitted light, By reducing the dimensions, the switch can be made more compact.

1-Note i (It is possible to lengthen the motion stroke of the moving object. Moreover, since it is configured to linearly control the amount of transmitted light of the light object, there is no need to electrically linearly correct the output of the light receiving element. 1. The circuit configuration becomes simple.

<Explanation of Examples> Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing an example of a non-contact switch according to the present invention, and FIGS. 2a and 2b are longitudinal sectional views showing the parfocal contact switch before operation and in an operating state, respectively.

In the figure, reference numeral 1 denotes a cylindrical switch body made of synthetic resin, which has a round hollow part 2, and openings at both front and rear ends in the axial direction are closed with a front cover 3 and a back cover 4, respectively.

Reference numeral 5 denotes a movable body made of synthetic resin disposed on the axis of the switch body 1, and on the front side there is a column-shaped operating body that protrudes forward through a through hole 6 formed in the front cover 3. Part 5
A is integrally formed, and four elastic legs 7 are connected to the outer periphery thereof and are equally spaced around the axis, and each elastic leg 7 is attached to the inner circumferential surface of the switch body l along the axis. They are respectively fitted into four guide grooves 8 formed.

A partition wall 9 that does not prevent the elastic legs 7 of the movable body 5 from passing through is integrally formed approximately at the center of the inner wall of the switch main body 1 in the axial direction.
A fan-shaped concave fill is formed on the axis of the light emitting element 10 to reflect the light from the light emitting element 10 backward. Reference numeral 12 denotes a means for applying a return force to the movable body 5, such as a return coil spring, which is hung between the front surface of the partition wall 9 and the operation section 5a.

13 is the above-mentioned partition wall 9! It is a cylindrical light shielding body located between AM4 and rotatably disposed coaxially with the axis of the switch body l, and the concave mirror 11 is mounted on its front wall as shown in FIG. A substantially butterfly-shaped slit 14 formed by connecting two sector shapes is formed corresponding to the slit 14 . Konoshiya light body 1
A plurality of spiral grooves 15 are formed on the outer peripheral surface of the elastic leg 3, and are fitted into a protrusion 16 formed at the tip of the elastic leg 7. Both of these 15 and 16 are the movable body 5
The light shielding member 13 is rotated and displaced by pushing the movable member 5, and the amount of light passing through the shield 14 of the reflected light from the concave mirror 11 is adjusted according to the pushing amount of the movable member 5. It is designed to change linearly.

18 is a light receiving element which receives the transmitted light and outputs an electric signal. 19 is 111 between the above-mentioned light shielding body 13 and back cover 4;
A backlash prevention spring 1 is hung, and 20 is a central hole formed in the back M4. A switch section A is constituted by the switch main body 1, the movable body 5, the shimmering light body 13, and the like.

Reference numeral B denotes a controller section, which incorporates the light emitting element 10, the light receiving element 18, and an amplifier circuit 21 (FIG. 4) for amplifying the electrical signal from the light receiving element 18. 2
Reference numeral 2 denotes a light-emitting side optical fiber for projecting the light from the light receiving element 10 to the concave mirror 11 through the central hole 20, and 23 is a light receiving side optical fiber for receiving the transmitted light from the slit 14 to the light receiving element 18. Both optical fibers 22.2
The switch section A and the controller section B are optically connected by the unit 24 of No. 3.

Next, the operation of the above configuration will be explained.

The light from the light emitting element 10 passes through the optical fiber 22 on the light emitting side and is projected from the central hole 20 of the JXM4 onto the concave mirror 11 of the switch body 1. The reflected light from the concave mirror 11 passes through the slit 14 of the light body 13 and is received by the light receiving element 18 through the central hole 20 and the optical fiber 23 on the light receiving side.

When the operating part 5a of the movable body 5 is pressed, the light body 13 is rotated around the axis of the switch body l by the protrusion 16 at the tip of the elastic leg 7, so that the amount of light transmitted through the sulin 14 is reduced. is linearly controlled to open and close.

That is, as shown in FIG. 5, the rotation angle of the shimmering light body 13 changes depending on the amount of pushing of the movable body 5, and as the rotation angle of the shimmering light body 13 increases, the amount of light transmitted through the slit 14 decreases. do. For example, when the movable body 5 is at points a, b, and a on the axis of the switch body 1, the rotation angle θ of the shimmering light body 13, that is, the rotation angle of the slit 14 are Oa and θ, respectively.
b, θC, and the amount of light received by the light receiving element 18 changes according to the characteristic shown by the straight line P in FIG.

Therefore, in the control section B, the light receiving element 18
By setting the threshold level of the amount of light received, for example, when the movable body 5 is located at point a, it is possible to obtain the ON-OFF switch output shown in the figure.

Here, since the movable body 5 disposed along the axis of the switch body 1 rotates the blocking body 13, which is set to be rotationally displaceable around the axis, the radial dimension of the switch body l is reduced. Therefore, it can be made more compact.

Furthermore, by setting the threshold level of the amount of light received by the light receiving element 18 in the controller section B, it is possible to obtain a switch output of 0N11OFF at the position in the axial direction of the movable body 5, and also to adjust the operating point. It's easy.

Furthermore, since the configuration is such that the amount of light transmitted through the slit 14 is linearly changed by rotationally displacing the shimmering light body 13, the change in the rotation angle of the shimmering light body 13 is reduced with respect to the change in the pushing amount of the movable body 5. If this is done, a long stroke can be easily realized.

By the way, as shown in FIG. 8(A), a ball lens 107 has already been placed between the light emitting element 102 and the light receiving element 103 on the axis of the switch body, and this ball lens 107 is used as a plunger. A movable body (not shown) that is movable along the axis has been devised. This is due to the displacement of the movable body, and the ball lens 107
The closer the angle of the light condensed to the light emitting element 102, the larger it changes, and as a result, the amount of light received by the light receiving element 103 changes according to the characteristic Q shown in FIG. The output signal from the light receiving element 102 can be electrically linearly corrected to obtain the switch output shown in FIG. 3(C).

In this case, in addition to the amplifier circuit 108 that amplifies the output of the light receiving element 103 as shown in FIG.
9 is required, resulting in a more complicated circuit and higher cost. Further, in the correction circuit 109, if the variation in one light emission and the light receiving elements 102, 103 is large, the linear characteristics will be directly affected.

Regarding this point, in the above embodiment, since the amount of transmitted light passing through the shield 14 of the light shielding body 13 changes linearly according to the pushing amount of the movable body 5, the signal processing circuit in the controller section B As shown in FIG. 4, the amplifier circuit 21 that simply amplifies the output of the light receiving element 18 eliminates the need for an electrical linear correction circuit, which simplifies the circuit configuration.
It is easy to reduce costs, and since the amount of light transmitted through the slit 14 is changed, variations in the light emitting element 10 and the light receiving element 18 do not affect the linear characteristics.

In the above embodiment, the backlash prevention spring 12 is interposed between the light body 13 and the back cover 4, but this can be omitted as shown in FIGS. 6a and 6b. It can also be configured using

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an example of a non-contact switch according to the present invention, FIGS. 2a and 2b are longitudinal cross-sectional views showing the same non-contact switch before and after operation, respectively.
FIG. 3 is a cross-sectional view of the non-contact switch, and FIG. 4 is a block diagram showing a signal processing circuit of a control section of the non-contact switch. FIG. 5 is an explanatory diagram of the operation of the non-contact switch, FIGS. 6a and 6b are longitudinal cross-sectional views showing other embodiments of the invention before and in operation, respectively, and FIG. Fig. 8 is a block diagram of a non-contact switch with the characteristics shown in Fig. 7, and Fig. 9 is a conventional non-contact switch. FIG. l...Switch body, 5...Movable body, 5a...Operation unit, 10...Light emitting element, 11...Concave mirror, 12...
. . . Returning means, 13 . . . Shining light body, 14 . . . Slit, 17 . Fig. 5 15: It accumulates 1° Fig. 2a Fig. 6a Fig. 6b Fig. Fig.

Claims (1)

[Claims] (1) A cylindrical switch body, a movable body having an operating part protruding from one end of the switch body in the axial direction, and fitted to the switch body so as to be able to move axially, and a movable body provided on the switch body. means for applying a restoring force to the movable body; a fan-shaped concave mirror disposed on the axis of the switch body to reflect light from the light emitting element; and a fan-shaped concave mirror for transmitting the reflected light from the concave mirror toward the light receiving element. a slit and rotatably disposed on the same axis as the concave mirror, and a push-in displacement of the movable body is converted into a rotational displacement of the bow-light body according to the pushing amount. A non-contact switch characterized by being equipped with a light body rotation and displacement means that linearly changes the amount of light transmitted through a slit.