JPH0422514Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of the Invention) The present invention relates to an electronic switch, and in particular, to an electronic switch that outputs a sensing signal when sensing an object, such as a cylindrical proximity switch or a photoelectric switch. and a light emitting means that emits light in response to the sensing signal, the sensing means is attached to one end in the longitudinal direction of the cylinder, the light emitting means is provided inside the cylinder, and the light emitting means emits light in the circumferential direction of the cylinder. The present invention relates to an electronic switch having a display hole provided at a location corresponding to the light emitting means for confirming the light emitting state of the light emitting means from the outside, and the cylindrical body being filled with a protective resin.

(Summary of the invention) The invention provides an electronic switch such as the following:
This makes it possible to avoid difficulty in confirming the light emitting state due to bubbles generated during resin filling.

(Prior Art and its Problems) A conventional electronic switch of this type was constructed as shown in FIG. FIG. 3 is a longitudinal sectional view.

In this figure, numeral 1 is a coil as a sensing means for sensing an object and outputting a sensing signal, and 2 is a light emitting diode as a light emitting means for emitting light in response to the sensing signal. The coil 1 and the light emitting diode 2 are connected via a circuit board 3, respectively. The circuit board 3 is housed in a cylindrical body 4, and the coil 1 is disposed at one end of the cylindrical body 4 in the longitudinal direction. Further, a cord 5 is connected to the circuit board 3, and the cord 5 is led out from an opening 4a at the end of the cylinder body 4 on the opposite side from the coil 1 in the longitudinal direction. The cylindrical body 4 is filled with a transparent resin 6 such as epoxy resin with the circuit board 3 installed therein. This resin 6
Ensure environmental resistance such as water resistance and humidity resistance, or
It is filled with the purpose of ensuring mechanical strength against vibrations, shocks, etc. light emitting diode 2
An indicator hole 7 is provided in the cylindrical body 4 at a position corresponding to the mounting location of the light emitting diode 2 and is set to have approximately the same size as the area of the light emitting part 2a of the light emitting diode 2. When the light emitting diode 2 emits light, this indicator hole From 7 onwards, you can check the lighting status.

By the way, when filling the resin 6, the resin 6 leaks from the display hole 7. Therefore, as shown in the drawings, conventionally, an adhesive tape 08 such as cellophane tape or Scotch tape is adhered tightly to the cylinder body 4 to close the display hole 7.

In order to prevent air bubbles from accumulating on the bottom surface of the cylinder 4, this resin filling is carried out with the bottom of the cylinder 4 facing down as shown. the result,
Air bubbles accumulate in the upper part of the display hole 7 within the thickness of the cylinder 4, and in this state, the resin is filled and solidified. However, in the conventional type, as mentioned above, the display hole 7
Since the size of the bubble A is almost the same as that of the light emitting part 2a of the light emitting diode 2, if a bubble A exists in the display hole 7, unevenness will occur on the surface of the resin within the display hole 7.
There was a drawback that the light from the light emitting diode 2 was subject to diffuse reflection, making it difficult to see the light from the light emitting diode 2.

Therefore, in order to prevent the generation of air bubbles A, it is conceivable to position the display hole 7 downward and fill it with resin 6, but in this case, air bubbles are likely to occur inside the cylinder 4, and the environmental resistance may deteriorate. The mechanical strength decreases, which reduces the life of the electronic switch itself, and the filling format of the resin cannot be changed.

(Purpose of the invention) The present invention was created in view of the above circumstances, and is intended to avoid the difficulty in confirming the light emitting state due to air bubbles, regardless of whether or not air bubbles are generated during resin filling. The purpose is to make it possible.

(Structure and Effects of the Invention) In order to achieve the above object, the electronic switch of the present invention has a surface area larger than the light emitting part of the light emitting means at a location corresponding to the light emitting means in the circumferential direction of the cylindrical body. A sheet material forming a first opening and having a second opening having an area equal to that of the light emitting part is attached to the outer circumferential surface of the cylindrical body with both the openings overlapping each other,
The first and second openings form the display as a hole.

According to this configuration, even if the resin is filled into the cylindrical body while the first opening is blocked with adhesive tape or the like, and bubbles are generated, the bubbles are directed to the peripheral side of the first opening, that is, to the light emitting means. After filling, the adhesive tape is removed and the sheet material is attached to the cylinder by gluing, etc., and both openings overlap each other to avoid air bubbles. It is possible to do so.

Therefore, there is no need to worry about the generation of air bubbles when filling the resin, and as with conventional methods, the resin can be filled with the bottom side of the cylinder facing down without generating air bubbles inside the cylinder, improving environmental resistance. In addition to ensuring mechanical strength, it also avoids unevenness of the resin caused by air bubbles from facing the display hole, suppresses diffuse reflection of light from the light emitting means, and allows the light to be clearly seen from the outside. Summer.

(Description of Embodiments) Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a longitudinal sectional view of an electronic switch according to an embodiment of the present invention. In the figure, 1 is a coil serving as a sensing means for sensing an object and outputting a sensing signal, and 2 is a light emitting diode serving as a light emitting means for emitting light in response to the sensing signal.
3 is a circuit board, 4 is a cylindrical body, and 5 is an opening 4a to which the circuit board 3 is connected at one end, and an opening 4a at the end opposite to the coil 1 in the longitudinal direction of the cylindrical body 4 at the other end.
The cord 6 led out to the outside is a transparent protective resin such as epoxy resin filled in the cylinder 4 with the circuit board 3 inside. 7 is a display hole for checking the light emitting state when the light emitting diode 2 emits light.

In the electronic switch having the above configuration, in the present invention, the display hole 7 includes a first opening 7a formed at a predetermined position in the circumferential direction of the cylinder 4, and an opening 4a of the cylinder 4.
A second opening 7b is formed in an adhesive tape 8 as a sheet material attached to the side outer peripheral surface by adhesive. The first opening 7a has a larger area than the light emitting part 2a of the light emitting diode 2,
It is formed into a long hole extending slightly upward from a location corresponding to the light emitting part 2a, and when filling with resin 6,
Even if air bubbles A are generated, the air bubbles A are removed from the first opening 7a.
It is configured to be positioned above the. The second opening 7b is the light emitting portion 2a of the light emitting diode 2.
It is formed in a perfect circular shape corresponding to the light emitting portion 2a and has an area approximately equal to that of the second opening 7b, and is arranged so that the second opening 7b overlaps the first opening 7a on the lower side.

The steps for manufacturing the electronic switch of the present invention are as follows: the first opening 7a is covered with a suitable adhesive tape, and the resin 6 is filled therein and solidified. After that, the adhesive tape is peeled off, and instead, an adhesive tape 8 with a second opening 7b formed thereon is attached to the cylinder 4 by adhesive or the like so that both openings 7a and 7b overlap in the above-described predetermined correspondence relationship.

The light emitting means is not limited to the above-mentioned light emitting diode 2, but various types such as a chipped light emitting element or a miniature lamp may be used as the case may be.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an electronic switch according to an embodiment of the present invention, FIG. 2 is a front view, and FIG. 3 is a longitudinal sectional view of a conventional electronic switch. DESCRIPTION OF SYMBOLS 1... Sensing means, 2... Light emitting means, 2a... Light emitting part, 4... Cylindrical body, 6... Resin, 7... Display hole,
7a...first opening, 7b...second opening, 8...sheet material.

Claims (1)

[Claims for Utility Model Registration] A sensing device that outputs a sensing signal when sensing an object, and a light emitting device that emits light in response to the sensing signal, the sensing device being placed at one end in the longitudinal direction of the cylinder. Attachment: The light emitting means is provided inside the cylinder, and an indicator hole is provided in a position corresponding to the light emitting means in the circumferential direction of the cylinder for confirming the light emitting state of the light emitting means from the outside, and an indicator hole is provided inside the cylinder. In the electronic switch, a first opening having an area larger than the light emitting part of the light emitting means is formed at a position corresponding to the light emitting means in the circumferential direction of the cylinder, and the first opening is formed in a position corresponding to the light emitting means in the circumferential direction of the cylinder, and second of equal area
An electronic switch comprising: a sheet having an opening attached to the outer circumferential surface of the cylindrical body with the openings overlapped with each other, and the display hole being formed by the first and second openings.