JP3321072B2 - Dial lighting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dial lighting structure for illuminating a design portion of a dial with light guided by a light guide plate.

[0002]

2. Description of the Related Art A conventional dial lighting structure is shown in FIGS.
As shown in FIG. 1, the design portion 5 of the dial 2 disposed on the light guide plate 1 is configured to be illuminated with the light L guided by the light guide plate 1.

That is, the dial 2 is formed by, for example, applying a black paint 4 to a general portion on the transparent substrate 3 to cover it, and applying a white paint to a portion where the design portion 5 is formed to form the design portion 5. Is done. The dial 2 is arranged such that the lower surface thereof is in contact with the upper surface of the light guide plate 1, and the light L guides the light L to illuminate the design portion 5 with the light L. . Note that reference numeral 7 in FIG. 4 is a pointer, and reference numeral 8 in FIG.

[0004]

However, in the conventional dial lighting structure, there is no problem in illumination if the design portion 5 of the dial 2 and the light guide plate 1 are completely laminated. As shown in FIG. 5, when the light guide plate 1 is arranged so that the end face 1 a thereof corresponds to an intermediate portion of the design part 5 due to an obstacle, for example, the inner protrusion 6 a of the meter case 6, the light guide plate 1 is placed in the design part 5. A thick line-shaped shadow 5a appears at a portion corresponding to the end face 1a, and a dark portion 5 is formed outside the shadow 5a.
b appears and has a problem of lowering the illumination quality.

Accordingly, the present invention provides a dial illuminating structure capable of maintaining a high level of illuminating quality irrespective of the arrangement structure in which the end surface of the light guide plate is arranged corresponding to the intermediate portion of the design portion of the dial. It is intended to provide.

[0006]

According to a first aspect of the present invention, a design portion of a dial disposed on a light guide plate is illuminated with light guided by the light guide plate. In the dial lighting structure as described above, the light guide plate is disposed so that an end surface thereof corresponds to an intermediate portion of the design portion,
An end portion including the end surface of the light guide plate has, on its upper surface and lower surface, an inclined refraction surface that refracts the light in the direction of the design portion and emits the light, and an inclined reflection surface that reflects the light in the inclined refraction surface direction. It is characterized by being provided and formed.

According to the first aspect of the present invention, the light guide plate is disposed such that the end face thereof corresponds to the intermediate portion of the design portion of the dial, and the design portion of the dial includes a portion that cannot be reached by the light guide plate. In spite of this, the whole of the design part including the part that cannot be reached by the light guide plate is illuminated by the light emitted from the inclined refraction surface. In addition, the amount of illumination light of the design portion is increased by the light reflected by the inclined reflection surface, whereby the luminance of the design portion can be improved.

According to a second aspect of the present invention, there is provided the dial illuminating structure according to the first aspect, wherein the inclined refraction surface is located at least inside the inner end of the design portion by the thickness of the dial. , And is formed to be inclined downward toward the end face with the starting point.

Therefore, according to the second aspect of the present invention, it is possible to prevent the appearance of a shadow due to the thickness of the dial inside the design portion, thereby uniformly illuminating the entire design portion.

According to a third aspect of the present invention, in the dial lighting structure according to the second aspect, the starting point of the inclined refraction surface is set to a position located at least 1 mm inward from the inner end of the design portion. It is characterized by:

Therefore, according to the third aspect of the present invention, it is possible to prevent the appearance of a shadow caused by the thickness of the dial inside the design part by absorbing the printing displacement of the design part.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 4 and 5 are denoted by the same reference numerals.

FIGS. 1 and 2 show a combination meter 10 to which a dial illumination structure according to an embodiment of the present invention is applied. The combination meter 10 is configured such that a plurality of instruments such as a speedometer, a tachometer, a fuel gauge, a water temperature gauge, and an odrip meter are incorporated in a meter case 6. A dial 8 is attached to the front of the meter case 6.

The dial illuminating structure at this time is configured to illuminate the design portion 5 of the dial 2 disposed on the light guide plate 1 with the light L guided by the light guide plate 1. Dial 2
In the same manner as in the prior art, for example, a black paint 4 is applied to a general portion on the transparent substrate 3 to cover it, and a white paint is applied to a formation portion of the design portion 5 to form the design portion 5. .

In particular, the dial lighting structure according to the present embodiment
As shown in FIG. 1, the light guide plate 1 has its end face 1a
The end portion 1A including the end surface 1a of the light guide plate 1 has an inclined refraction surface 1B and a light beam which refract the light L1 toward the design portion 5 and emit the light L1 on the upper surface and the lower surface, respectively. It is formed with an inclined reflecting surface 1C for reflecting L2 in the direction of the inclined refracting surface 1B. The light guide plate 1 is arranged such that the end face 1a thereof corresponds to the intermediate portion of the design part 5 because the end face 1a and the obstacle in the meter case 6, in the present embodiment, the inner protrusion 6a of the meter case 6 This is to avoid interference.

More specifically, the inclined refracting surface 1B is located at a position located at least by the thickness of the dial 2 from the inner end 5c of the design portion 5, more specifically, at a position located inward by the thickness t of the transparent substrate 3 constituting the dial 2. The starting point A is formed to be inclined downward toward the end face 1a. Further, the inclined reflecting surface 1C is formed to be inclined upward toward the end surface 1a with a position outside the starting point A of the inclined refracting surface 1B as a starting point B.

The inclined refracting surface 1B thus formed is
The appearance of the shadow caused by the thickness of the dial 2 (the thickness t of the transparent substrate 3) inside the design portion 5 can be prevented, and the entire design portion 5 can be uniformly illuminated. That is, as shown in FIG. 3, when the inclined refracting surface 1B is formed at a position that coincides with the inner end 5c of the design portion 5 as a starting point A1, the inner portion of the design portion 5 is caused by the thickness t of the transparent substrate 3. There is an opaque portion R of the light emitted from the inclined refraction surface 1B, and the opaque portion R appears as a shadow. However, the opaque portion R is formed by forming the inclined refraction surface 1B as described above. R can be eliminated.

The starting point A of the inclined refracting surface 1B is preferably set at a position located at least 1 mm inward from the inner end 5c of the design portion 5. With this setting, the inclined refraction surface 1B is
A position shifted from the inner end 5c of the design portion 5 to a position sufficiently inward of a distance corresponding to the thickness t of the transparent substrate 3 is formed as a starting point A. According to the inclined refraction surface 1B formed in this way, it is possible to absorb the printing deviation of the design part 5 and to eliminate the above-mentioned opaque portion R with a margin, whereby the dial inside the design part 5 can be eliminated. 2 (thickness t of the transparent substrate 3)
Can prevent the appearance of shadows caused by the above.

The inclination angle θ 1 of the inclined refraction surface 1 B and the inclination angle θ 2 of the inclined reflection surface 1 C are determined by the refractive index of the light guide plate 1 and the starting point A.
Is appropriately determined such that the entire design part 5 is uniformly illuminated by the set position of the design part 5 and the relative positional relationship between the design part 5 and the end face 1a of the light guide plate 1.

According to the dial illuminating structure thus constructed, the light L1 guided parallel to the upper portion of the light guide plate 1 is refracted by the inclined refraction surface 1B and emitted toward the design portion 5 to be designed. The part 5 can be illuminated. At this time, the light guide plate 1 is disposed with its end face 1a corresponding to the intermediate portion of the design portion 5 of the dial 2, and although the design portion 5 of the dial 2 includes a portion that the light guide plate 1 cannot reach. In addition, the entire design portion 5 including the portion that cannot be reached by the light guide plate 1 is uniformly illuminated by light (shown by a solid line in FIG. 1) emitted from the inclined refraction surface 1B.

The light L2 guided parallel to the lower portion of the light guide plate 1 is reflected by the inclined reflecting surface 1C in the direction of the inclined refracting surface 1B, and refracted by the inclined refracting surface 1B to be directed in the direction of the design portion 5. The light can be emitted to illuminate the design part 5. Therefore, the amount of illumination light of the design portion 5 is increased by the light reflected by the inclined reflection surface 1C (indicated by a broken line in FIG. 1), whereby the luminance of the design portion 5 can be improved.

[0022]

As described above, according to the first aspect of the present invention, the light guide plate is disposed with its end face corresponding to the intermediate portion of the design portion of the dial, and the design portion of the dial is formed by the light guide plate. Despite including the portion that the plate does not reach, the entire design portion including the portion that the light guide plate does not reach is uniformly illuminated by the light emitted from the inclined refraction surface, and the reflected light by the inclined reflection surface The illumination light amount of the design part increases,
As a result, the luminance of the design portion can be improved, so that a high level of illumination quality can be generally maintained.

According to the second aspect of the present invention, the appearance of the shadow caused by the thickness of the dial inside the design portion can be prevented, and the entire design portion can be uniformly illuminated. Can be planned.

According to the third aspect of the present invention, it is possible to prevent the appearance of a shadow caused by the thickness of the dial inside the design part by absorbing the printing deviation of the design part, thereby improving the illumination quality. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view taken along the line II of FIG. 2 showing a dial illumination structure according to an embodiment of the present invention.

2 is an external perspective view of a combination meter to which the dial illumination structure of FIG. 1 is applied.

FIG. 3 is a sectional view of a main part as a comparative example of the present invention.

FIG. 4 is a plan view of a main part of an instrument to which a conventional dial illumination structure is applied.

5 is a cross-sectional view of the conventional dial illumination structure taken along line VV in FIG.

[Explanation of symbols]

 Reference Signs List 1 light guide plate 1a end surface (of light guide plate) 1A end portion (of light guide plate) 1B inclined refraction surface 1C inclined reflection surface 2 dial plate 5 design portion 5c inner end (design portion) A start point (of inclination refraction surface) t transparent Board thickness (thickness of dial) L1, L2 Light

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01D 13/02 G01D 11/28 G12B 11/02

Claims (3)

(57) [Claims] 1. A dial illuminating structure in which a design portion of a dial placed on a light guide plate is illuminated with light guided by the light guide plate, wherein the light guide plate has an end face having the design. An end portion including the end surface of the light guide plate is disposed so as to correspond to an intermediate portion of the portion, and an inclined refraction surface and the light which refract the light toward the design portion and emit the light on the upper surface and the lower surface, respectively. Characterized by being provided with an inclined reflection surface for reflecting the light in the direction of the inclined refraction surface. 2. The dial illuminating structure according to claim 1, wherein the inclined refraction surface is located at a position located at least inside the dial by the thickness of the dial from an inner end of the design portion. A dial lighting structure characterized by being formed with a downward slope. 3. The dial illumination structure according to claim 2, wherein a starting point of the inclined refraction surface is 1 m from an inner end of the design portion.
A dial lighting structure characterized by being set at a position located at least m inward.