JPH0539457Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a lighting device for instruments, and in particular to a lighting device that indirectly illuminates the pointer using light leaking from the gap between the dial and the dial. It is related to.

[Problems to be solved by conventional techniques and ideas]

Conventionally, various devices have been devised to indirectly illuminate the pointer of a meter.

FIG. 2 is a diagram showing a schematic configuration of a conventional illumination device, in which a pointer 3 attached to a pointer shaft 2 driven by an internal mechanism (not shown) is arranged at the front of the center of the dial 1. A facing plate 4 is provided around the front of the dial 1 to cover all but the required portions of the dial 1.

A light source 5 for illuminating the pointer 3 is provided behind the dial plate 1 and dial plate 4, and the light from the light source 5 leaks from a gap 6 between dial plate 4 and dial plate 1 as shown by the arrow in the figure. , illuminates the pointer 3 and the dial surface.

However, in the case of the above-mentioned lighting device, in addition to the light leaking from the case 7 in parallel to one face of the dial, as shown in the figure, there is also light reflected from the facing plate 4, etc. There is light irradiated toward a local area A. Therefore, the local area A becomes brighter than the surrounding area, and the illumination on the dial 1 becomes uneven.

Therefore, conventionally, in order to prevent the reflected light from the facing plate 4 as described above, the opening edge 4 of the facing plate 4 is
Forming ribs on a.

FIG. 3 shows such a conventional device, in which a rib 4b is provided below the edge 4a of the facing plate 4 to further protrude as shown by a broken line. However, the ribs 4b are not provided over the entire circumference of the opening edge 4a, but are formed in portions corresponding to portions of the dial 1 where the illumination is locally strong. In this way, as shown in the figure, for example, reflected light from the lower surface of the facing plate 4 will not directly reach the upper surface of the dial plate 1, and uneven illumination can be prevented.

As an alternative method, as shown by broken lines in FIG. 3, an extension portion 1a is formed in which the outer diameter of the dial plate 1 is partially increased. This also makes it possible to prevent the reflected light from the lower surface of the facing plate 4 from being guided onto the dial.

However, both of the above methods have the disadvantage that the illumination becomes dark because a portion of the indirect light is blocked, and it is extremely difficult to adjust the light amount using partially provided ribs, extensions, etc. , which is still not sufficient to obtain uniform illumination.

Also, if the opening edge 4a of the facing plate 4 is partially extended, this part will be visible from the front, so
Problems also remain in terms of design.

The present invention has been made in view of the above points, and aims to provide an instrument lighting device that can provide uniform brightness without reducing the brightness of the illumination.

[Means for solving problems]

In order to achieve the above object, the instrument illumination device developed according to the present invention includes a dial with a pointer on the front, a facing plate that covers the front periphery of the dial, and a dial that covers the front of the dial. In an instrument lighting device that reflects light from a provided light source on the inner surface of the case and allows the reflected light to leak through a gap between a dial and a facing plate to indirectly illuminate the pointer and the front of the dial. A projecting wall is formed to hang downward on the lower surface of the facing plate between the opening edge of the facing plate away from the opening edge and the inner surface of the case, and the projecting wall is formed so as to hang downward from the facing plate and prevents the light from the light source reflected by the facing plate. It is characterized by being diffused by walls.

[Effect]

With the above configuration, the projecting wall formed on the lower surface of the facing board diffuses the light from the light source that is reflected by the facing board, so the light that is reflected by the facing board is not directly reflected, but is diffused by the projecting wall. Diffused light is guided from the gap between the dial and dial plate to the hands and the front surface of the dial.

〔Example〕

FIG. 1 shows an embodiment of the invention. In the figure, the structure of the dial 1, hands 3, etc. is similar to that of the conventional example, but there is a difference from the conventional example in that a projecting wall 4c is integrally formed inside the facing plate 4.

As shown in the figure, this projecting wall 4c is provided on the lower surface of the facing plate 4 away from the opening edge 4a so that the light from the light source 5 is not reflected by the facing plate 4 and directly reaches the top of the dial 1. It is formed to hang downward. Although the height of the protruding wall 4c is set appropriately, it is desirable that the height is set so that at least the final leakage of illumination light from the gap 6 is not obstructed.
It is desirable that the length of the projecting wall 4c be uniform over the entire circumference of the opening edge 4a, but in some cases it may be formed partially at uneven locations.

In this embodiment, the light from the light source 5 is transmitted to the case 7, the lower surface of the facing plate 4, the inner wall of the opening edge 4a, and the projecting wall 4c.
etc., and is then guided to the front of the pointer 3 and dial 1. Therefore, the guided light is diffused and becomes uniform illumination light throughout.

[Effect of idea]

The present invention is as described above, and is designed to guide diffused light to the front of the instrument without narrowing the gap between the facing plate and the dial by using the protruding wall located away from the edge of the opening. Therefore, even and uniform illumination can be easily performed over the entire area without reducing brightness.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram of an embodiment of the present invention, FIG. 2 is a structural diagram of a conventional example, and FIG. 3 is a structural diagram of another conventional example. 1...Dial board, 3...Pointer, 4...Return board,
4a...Opening edge, 4c...Protruding wall, 5...Light source,
6...Gap, 7...Case.

Claims (1)

[Scope of claim for utility model registration] The case is equipped with a dial plate with a pointer on the front and a dial plate that covers the front periphery of the dial plate, and the case In an instrument lighting system that reflects light from the inner surface and leaks the reflected light through the gap between the dial and dial plate to indirectly illuminate the hands and the front of the dial, A projecting wall is formed so as to hang downward on the lower surface of the facing plate between the opening edge and the inner surface of the case, and the projecting wall diffuses the light from the light source that is reflected by the facing plate. Lighting device for the instrument.