JPH0559722U - Backlight illumination switch unit - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce the manufacturing cost of backlight illumination switch units. [Structure] A key top 22 and a surface sheet 23 are juxtaposed on the upper surface of the case 21, and a switch 25 arranged on a substrate 24 directly below the key top 22 in the case 21 has a slider 26 interposed therebetween. A reflector 11 made of a semitransparent resin is obliquely provided between the light source 27 provided on the substrate 25 and the surface sheet 23 below the surface sheet 23.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a backlight illumination type switch unit, and more specifically to improvement of a switch unit of a type in which a key top and a surface sheet are illuminated by a rear light source, which is mainly used in electronic devices and the like. ..

[0002]

[Prior Art]

 Fig. 2 shows a typical configuration of a conventional backlight illumination type switch unit of this type. This is a sectional view taken along line AA of a switch having an upper surface as shown in FIG. 3, for example.

A key top 22 made of resin and a surface sheet 23 are juxtaposed on the upper surface of the case 21. A board 24 is horizontally provided in the lower part of the case 21, and a switch 25 which is to be operated by pressing the keytop 22 is installed on the board 24 at a position almost directly below the keytop 22. There is. The switch 25 is operatively connected to the key top 22 via a slider 26 slidably installed on the case 21. A light source 27 is provided on the substrate 24 adjacent to the switch 25 at a position substantially below the surface sheet 23. Between the light source 27 and the key top 22, a light guide 28 made of transparent resin and having a complicated structure is fixed to the case 21. Further, a smoke filter 29 is attached to the lower surface of the surface sheet 23.

On the one hand, the light from the light source 27 is guided by the light guide 28 to just below the key top 22. This light also directly enters the surface sheet 23. Here, the smoke filter 29 serves to soften the intense light that is directly incident and make the brightness of the top sheet 23 equal to that of the key-top 22.

[0005]

In such a conventional backlight illumination type switch unit, since the switch 25 and the light source 27 are arranged side by side on the same substrate 24, the light guide 28 is used. I have no choice. Since the light guide 28 is thick and has a complicated shape, it is difficult to perform injection molding, takes a long molding time, and has a very low yield, resulting in a high manufacturing cost. Further, when the light guide body 28 is assembled into the switch unit, the tip of the light guide body must be accurately arranged directly below the key top 22, so that adjustment operation in the vertical and horizontal directions is required, and the assembling cost becomes high. Therefore, the manufacturing cost of the entire switch unit is inevitably high.

An object of the present invention is to reduce the manufacturing cost of a backlight illumination type switch unit.

[0007]

[Means for Solving the Problems]

 According to the present invention, a switch housed in a case, a key top connected to the switch via a slider and exposed to the upper surface of the case, and a surface provided on the upper surface of the case so as to be adjacent to the key top. In a backlight illumination type switch unit having a sheet and a light source housed in the case and illuminating the key top and the surface sheet, the light source is provided to face the surface sheet, and the light source and the surface sheet are provided. A backlight illumination switch unit is obtained in which a reflector made of a translucent resin is obliquely provided between the light sources so that the light source illuminates the key top and the surface sheet.

[0008]

[Action]

 A part of the light from the light source is reflected by the reflector and the slider to reach the key top, and the remaining part of the light passes through the reflector to reach the top sheet.

[0009]

【Example】

 FIG. 1 shows an embodiment of the present invention. Parts that are substantially the same as those of the conventional switch unit shown in FIG. 2 are given the same reference numerals. A key top 22 and a surface sheet 23 are provided side by side on the upper surface of the case 21, and a switch 25 arranged on a base plate 24 directly below the key top 22 in the case 21 is operatively connected to the key top 22 via a slider 26. This is the same as the conventional switch unit. Since the reflection effect of the slider 26 is also utilized in this invention, the slider 26 having a reflecting surface made of white resin is used. Further, a translucent reflector 11 is provided on the case 21 at a position directly above the light source 27 and below the surface sheet 23. The reflector 11 is formed of a resin that transmits light, and is obliquely arranged so as to reflect the light from the light source 27 toward the slider 26.

A part of the light from the light source 27 is reflected by the reflector 11 and the slider 26 to reach the key top 22, and the remaining part of the light is transmitted through the reflector 11 to reach the top sheet 23.

Here, the amount of light reaching the surface sheet 23 (or the amount of light reaching the key top 22) changes depending on the light transmittance of the reflector 11. Therefore, by appropriately selecting the material used for the reflector 11, the illumination balance between the key top 22 and the surface sheet 23 can be freely adjusted.

[0012]

[Effect of the device]

 Since a simple flat-plate reflector is used instead of the conventional complicated structure, the manufacturing cost is low and the position adjustment at the time of assembly is easy, so the manufacturing cost is greatly reduced as a whole. Moreover, since the reflector is used to efficiently reach the keytops where it is difficult for the light from the light source to reach, and the light toward the surface sheet is attenuated here, it is necessary to use the smoke filter that was used in the past. The cost will be further reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of a conventional switch unit.

FIG. 3 is a top view of a switch unit.

[Explanation of symbols]

 11 Retractor 21 Case 22 Key Top 23 Surface Sheet 24 Substrate 25 Switch 26 Slider 27 Light Source 28 Light Guide 29 Smoke Filter

Claims (1)

[Scope of utility model registration request] 1. A switch housed in a case, a key top connected to the switch via a slider and exposed on the top surface of the case, and a surface sheet provided on the top surface of the case so as to be adjacent to the key top. A backlight illumination type switch unit housed in the case and having a light source for illuminating the key top and the surface sheet, wherein the light source is provided facing the surface sheet, and between the light source and the surface sheet. A backlight illumination switch unit, wherein the light source illuminates the key top and the surface sheet by obliquely installing a reflector made of a semitransparent resin.