JPH0712596A - Illumination structure for instrument - Google Patents

Abstract

PURPOSE:To improve an illumination efficiency by separately providing an endless reflecting wall for guiding a light to a rear surface of a character plate from an inner machine along inside and outside of a plurality of light sources. CONSTITUTION:A bottom reflecting wall 9 is fixed separately from a rear surface plate 4 by a plurality of legs 9a, insertion holes 9b of a plurality of electric lamps 5 are formed at positions corresponding to the lamps 5, and a light is reflected to a transmission part 2 side of a character plate 1 via an oblique surface 9c. A side reflecting wall 10 is formed in an endless state by inner, outer and end side reflecting walls 10a, 10b, 10c, inclined so as to be separated from the lamps 5 toward the plate 1 and to reflect the light to the part 2 side. Thus, since the lights from the lamps 5 are applied directly to or through the walls 9, 10 to the part 2 side of the plate 1, the illumination efficiency of the part 2 is improved. Heats of the lamps 5 are dissipated from the holes 9b to an output of a meter case 3 through vent holes 4a to suppress a temperature rise therein.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination structure of an instrument for shining brightly a light transmitting portion such as characters and scales on a dial by a light source provided on the back side of the dial.

[0002]

2. Description of the Related Art Conventionally, as an illumination structure of an instrument of this type, those shown in FIGS. 9 and 10 are known. That is, the dial 1 is provided with a transmissive portion 2 such as characters and scales through which light can be transmitted, and the back plate 4 of the meter case 3 radiates light to the back side of the dial 1 ( A light source) 5 is provided. A pointer 6 is arranged on the front side of the dial 1, and the pointer 6 is driven by an internal unit 7 fixed to the back plate 4. The dial 1 itself is fixed to the bracket portion 7a of the inner unit 7 with screws.

[0003]

However, in the above-mentioned conventional illumination structure for measuring instruments, the light emitted from the light bulb 5 is dispersed in all directions, which is convenient for illuminating a wide range. When illuminating only the transmission part 2 of 1,
There is a problem that the lighting efficiency becomes poor.

In order to solve the above problems, for example, the one disclosed in Japanese Utility Model Laid-Open No. 60-41822 is disclosed. However, this invention merely arranges the optical path guide wall outside the display portion of the dial plate and surrounds the illumination lamp, so that the light emitted from the illumination lamp is dispersed outward. Although it can be prevented, it is the current situation that the above-mentioned problems and the problems that the internal unit is easily affected by heat cannot be solved.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an illumination structure for an instrument capable of improving the illumination efficiency when illuminating the transparent portion of the dial. Especially.

[0006]

In order to achieve the above object, the present invention is an instrument for driving a pointer provided on the front side of the dial by an internal machine provided on the back side of the dial. , In a lighting structure of an instrument for illuminating a transmissive part formed in a peripheral portion of the dial by a plurality of light sources arranged around the inner unit, along the inside and the outside of the plurality of light sources, An endless reflection wall that guides light to the back side of the dial is provided separately from the internal unit. Further, it is preferable that the reflection wall has a cooling fin projecting outside from a meter case that covers the rear of the inner unit.

[0007]

In the illumination structure for an instrument constructed as described above, the light emitted from the light source reaches the back side of the dial directly or through the reflecting wall. Therefore, the illumination efficiency is improved, and the brightness of each light source or the number of light sources can be reduced. Further, since the amount of heat emitted from the light source can be reduced by reducing the brightness of the light source or the number of light sources, it is possible to improve the reliability of the internal unit and the like.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. However, elements common to the constituent elements of the conventional example shown in FIGS. 9 and 10 are designated by the same reference numerals to simplify the description.

As shown in FIGS. 1 to 3, a plurality of (in this embodiment, in this embodiment) rear plate 4 of the meter case 3 corresponding to the horseshoe-shaped transparent portion 2 formed on the peripheral portion of the dial 1. Three (3) light bulbs (light sources) 5 are provided, and a reflection wall 8 is provided so as to cover the side and the rear of these light bulbs 5. The reflection wall 8 is integrally formed by a bottom reflection wall 9 covering the rear of each light bulb 5 and a side reflection wall 10 extending from a side edge of the bottom reflection wall 9 to a position reaching the dial 1.

The bottom reflection wall 9 is fixed at a position separated by a predetermined length from the back plate 4 by a plurality of legs 9a, and an insertion hole 9b for inserting the light bulb 5 is provided at a position corresponding to the light bulb 5. Has been formed. The insertion hole 9b also serves as ventilation, and is formed larger than the diameter of the light bulb 5. However, the diameter of the insertion hole 9b is large enough not to impair the reflection by the bottom reflecting surface 9. The bottom reflection wall 9 is formed in a horseshoe shape that continuously connects the insertion holes 9b, and a mountain-shaped inclined surface 9c is formed in the central portion between the adjacent insertion holes 9b. The light emitted from the light bulb 5 is reflected by the inclined surface 9c toward the transparent portion 2 side of the dial 1.

The side reflection wall 10 has an inner side reflection wall 10a extending from the inner side edge of the bottom reflection wall 9 formed in a horseshoe shape to the dial 1 side, and the outer side edge of the bottom reflection wall 9 from the dial 1 side.
The outer side reflection wall 10b extending toward the side and the end side reflection wall 10c extending from the end side edge of the bottom reflection wall 9 toward the dial 1 side are endlessly formed. Each of these side reflection walls 10a, 10b, 10c is inclined in a direction away from the light bulb 5 toward the dial 1, and the light emitted from the light bulb 5 is reflected to the transmitting portion 2 side of the dial 1. It is like this.

A ventilation hole 4a is formed on the back plate 4 of the meter case 3 along the bottom reflection wall 9 and close to the insertion hole 9b.

According to the illumination structure of the instrument configured as described above, the light emitted from each light bulb 5 is transmitted directly or through the bottom reflecting wall 9 and the side reflecting wall 10 to the transmitting portion 2 of the dial 1. Reach Therefore, the efficiency of illuminating the transparent portion 2 of the dial 1 is improved. The improvement in illumination efficiency can reduce the brightness of each light bulb 5 or the number of light bulbs 5, so that the cost can be reduced and the amount of heat emitted from the light bulb 5 can be reduced.

Further, as shown by the dotted line in FIG. 2, the heat emitted from the light bulb 5 is released from the insertion hole 9b to the outside of the meter case 3 through the ventilation hole 4a. Along with the reduction in the amount of heat generated by the light bulb 5, it is possible to suppress the temperature rise inside the reflection wall 8 and inside the meter case 3, and it is possible to improve the reliability of electrical equipment and the like.

The reflection wall 8 may be formed of resin integrally with the back plate 4, or may be formed of a metal separately from the back plate 4. And if it is made of resin,
It is preferable to use a white resin or to plate the reflecting surface to improve the reflection efficiency.

In the above embodiment, the reflecting wall 8 having the bottom reflecting wall 9 is shown, but the bottom reflecting wall 9 may not be provided. However, in this case, it is preferable to provide a gap between the side reflection wall 10 and the back plate 4 by the leg portions 9a and the like. Further, it is preferable that at least a portion of the back plate 4 corresponding to the bottom reflection wall 9 is formed in a white color or is plated.

Further, the rear plate 4 is provided with a ventilation hole 4a at a position corresponding to the bottom reflection wall 9, but this ventilation hole 4a.
Needless to say, it may be provided at another position, and the ventilation hole 4a may not be provided.

Further, although the side reflection wall 10 is provided obliquely with respect to the dial 1, the side reflection wall 10 may be provided perpendicular to the dial 1.

Next, a second embodiment of the present invention will be described with reference to FIGS. However, elements common to the first embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals, and description of the same components will be omitted.

The reflector 8 in the second embodiment is made of iron,
It is formed by pressing a metal material having a high thermal conductivity such as aluminum, and the bottom reflection wall 9 has a rectangular insertion hole 9b. The insertion hole 9b is formed by punching the bottom reflection wall 9 in a U shape and bending it outward.
The bent piece K serves as the leg portion 9a and the cooling fin 9c. That is, the bent piece K has a leg portion 9a at its base end and a slightly narrower cooling fin 9c at the tip end side of this leg portion 9a. It is designed to project backward from. Also,
The end side reflection wall 10c is formed integrally with the back plate 4.

In the illumination structure for a meter constructed as described above, the temperature of the reflection wall 8 can be lowered by the cooling fins 9c, so that the reliability of electric equipment and the like can be further improved. Others have the same effects as those of the first embodiment.

The cooling fin 9c may be connected to another component for cooling to further enhance the heat radiation effect. Also, on the reflective surface of the reflective wall 8, white paint,
It is preferable to improve the reflection efficiency by applying plating or the like.

[0023]

According to the present invention, the light emitted from the light source reaches the back side of the dial directly or through the reflecting wall.
Therefore, the illumination efficiency can be improved. The improvement in illumination efficiency can reduce the brightness of each light source or the number of light sources, so that the cost can be reduced and the amount of heat emitted from the light sources can be reduced. Also, by reducing the amount of heat emitted from the light source, the reliability of the internal unit, etc. can be improved, while the endless reflecting wall is provided separately from the internal unit, so the heat of the light source has a negative effect on the internal unit. It can be surely prevented from affecting.

[Brief description of drawings]

FIG. 1 is a perspective view of a lighting structure of an instrument shown as a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

3 is a sectional view taken along the line BB of FIG.

FIG. 4 is a perspective view of a lighting structure of an instrument shown as a second embodiment of the present invention.

FIG. 5 is a plan view of an illumination structure of the instrument.

6 is a cross-sectional view taken along the line CC of FIG.

7 is a cross-sectional view taken along the line DD of FIG.

8 is a cross-sectional view taken along the line D-D of FIG. 5, showing a reflection wall and a back plate.

FIG. 9 is a perspective view of a lighting structure of an instrument shown as a conventional example.

FIG. 10 is an internal side view of a lighting structure of the instrument.

[Explanation of symbols]

 1 Dial 3 Meter Case 4 Back Plate 5 Light Source (Light Bulb) 6 Pointer 7 Internal Machine 8 Reflection Wall 9c Cooling Fin

Claims (2)

[Claims] 1. An internal machine provided on the back side of the dial,
In an instrument lighting structure for driving a pointer provided on the front side of the dial, the instrument illuminating a transparent portion formed on a peripheral portion of the dial by a plurality of light sources arranged around the inner unit. An illumination of an instrument characterized in that an endless reflection wall for guiding the light of these light sources to the back side of the dial is provided along the inside and the outside of the plurality of light sources separately from the inner unit. Construction. 2. The lighting structure for an instrument according to claim 1, wherein the reflection wall has a cooling fin projecting to the outside from a meter case covering the rear of the internal unit.