JP3401787B2 - Pointer lighting device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointer illuminating device which uses a light guide to guide light from a light source to a pointer and illuminates the pointer.

[0002]

2. Description of the Related Art A light guide is used to guide light from a light source to a pointer to illuminate the pointer brightly.
There is 9896 publication. In this optical indicator, as shown in FIG. 4 of the above publication, the incident surface of the light guide plate 13 is formed into a concave portion 21-1 so as to surround the light source 16-1.
The amount of light entering the light guide plate 13 from -1 is increased so that the pointer is illuminated brightly.

[0003]

In the above-mentioned conventional example, although the amount of light entering the light guide plate 13 is large, the light is emitted from the light source 16-
Since the light travels radially from the inside of the light guide plate 13 from 1, the amount of light that travels outside the mounting hole 23 of the pointer 11 is large, and the amount of light that directly travels to the mounting hole 23 is small. Nevertheless, the light that has proceeded to the peripheral surface of the horizontal plane portion is reflected by the reflection curved surface portions 22-1 to 22-4 and is attached to the mounting hole 23.
Therefore, it is more effective than the conventional specifications described in the above publication. However, a large amount of light travels between the mounting hole 23 and the reflection curved surface portions 22-1 to 22-4. Further, some light may be reflected on the reflection curved surface portion, or may progress while repeating reflection even within the thickness of the light guide plate 13, so that some light may be attenuated or may escape to the outside of the light guide plate 13.

The present invention has been made in view of the above circumstances, and provides a pointer illuminating device which efficiently guides the light incident from the light source to the light receiving portion of the light guide to the pointer to illuminate the pointer brighter. The purpose is to do.

[0005]

In order to achieve the above-mentioned object, the present invention has a pointer, a flat portion and a bent portion for guiding the light of a light source to the pointer, and between the flat portion and the bent portion. The bent portion has a light receiving portion, a second reflecting surface for reflecting the light incident on the light receiving portion, and a light reflected by the second reflecting surface. The second reflecting surface and the light receiving section are formed in a circular arc shape in cross section which is rotated about a light source axis passing through the light source as a base line.

Further, the present invention includes a light guide having a pointer, a flat portion for guiding the light of the light source to the pointer and a bent portion, and a first reflecting surface provided between the flat portion and the bent portion. The bent portion includes a light receiving portion, a second reflecting surface that reflects the light incident on the light receiving portion, and a light guide portion that guides the light reflected by the second reflecting surface to the first reflecting surface. The bent portion has an arc-shaped cross section that is rotated about a light source axis passing through the light source as a base line.

Further, the second reflecting surface is provided so that the light reflected by the second reflecting surface becomes substantially perpendicular to the plane portion.

Further, the light source axis is substantially perpendicular to the plane portion.

The light source axis is substantially parallel to the light reflected by the second reflecting surface.

Further, the light receiving section has a light receiving surface having a convex arcuate cross-section with the light source as a substantially focal point.

Further, the first reflecting surface is composed of a divided flat surface.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described as an embodiment of a pointer illumination device used in a vehicle instrument. 1 to 5 show a first embodiment of the present invention. On the front surface side of the circuit board 1, for example, an instrument main body 2 for a speedometer is arranged in a state of being electrically connected to the circuit board 1. Reference numeral 3 is a pointer fixed to the instrument body 2 and operated according to the speed of the vehicle. A display plate 4 and a light guide 5 are arranged between the instrument body 2 and the pointer 3. Reference numeral 6 denotes a bulb as a light source which is attached to the circuit board 1 together with electronic components (not shown) for driving the instrument body 2 and illuminates the pointer 3 and the display plate 4.

The pointer 3 is an indicator 7 made of a light-transmissive resin.
A pointer shaft 8 integrally formed with the pointing portion 7, a black pointer cap 10 as a light shielding member that covers the periphery of the base portion 9 of the pointing portion 7 (above the pointer shaft 8), and a balancer 11. The indicator 7 and the pointer shaft 8 may be separate bodies. Then, the pointer 3 is fixed to the meter body 2 by press-fitting the pointer shaft 8 into the rotary shaft 12 of the meter body 2.

Although not shown, the display plate 4 arranged behind the pointer 3 has a transparent white display such as a scale or a number indicating the speed of the vehicle to be indicated by the pointer 3 on the surface side of a colorless and transparent substrate. The display section is adapted to receive the illumination light from the bulb 6 directly or via the light guide 5 for transmissive display. The parts other than the display part are covered with a black ground color layer.

The light guide 5 is made of a light-transmissive resin and has a flat surface portion 13 and a bent portion 14 which are substantially parallel to the pointing portion 7 of the pointer 3. A first reflecting surface 15 is provided between the flat surface portion 13 and the bent portion 14. The bent portion 14 is the valve 6
The light receiving portion 16 protruding to the side, the second reflecting surface 17 for reflecting the light incident on the light receiving portion 16, and the light guiding for guiding the light reflected by the second reflecting surface 17 to the first reflecting surface 15. Part 1
8 and. Here, the angle of the second reflecting surface 17 is set so that the light reflected by the second reflecting surface 17 becomes substantially perpendicular to the flat surface portion 13. Along with that, the light guide portion 18 also has a flat surface portion 1.
It is formed so as to be substantially perpendicular to 3. Further, the first reflecting surface 15 is set to be inclined by 45 degrees. Although the second reflecting surface 17 of the present embodiment extends to the back surface of the flat surface portion 13, it may have the shape shown by the broken line Y. Also,
As shown in FIGS. 2 and 4, the first reflecting surface 15 is composed of a plane (divided reflecting surface 15A) divided into three parts.

The light receiving section 16 has a cross section in the thickness direction of the bulb 6.
Has a convex arcuate light-receiving surface 16A whose focal point is substantially. In addition, the bent portion 14 passes through the valve 6 and the flat surface portion 13
The cross section rotated about the light source axis X, which is substantially perpendicular to, is arcuate. That is, the light receiving portion 16 (light receiving surface 1
6A), the second reflection surface 17, and the light guide portion 18 have a cut (cross section) in a direction orthogonal to the light source axis X in an arc shape with the light source axis X as the origin. Further, a third reflecting surface 19 is provided around the through hole in which the pointer shaft 8 of the pointer 3 is inserted, and the light reflected by the first reflecting surface 15 and transmitted through the flat portion 13 is guided by the pointer 3. The light is reflected on the pointer reflecting surface 20 side.

In the pointer illuminating device having such a structure, the light receiving portion 16 (light receiving surface 16A) has an arc-shaped cross section which is rotated about the light source axis X as a base line.
Light that radially travels from the light receiving portion 16 to the light receiving portion 16 does not reflect on the light receiving surface 16A and is perpendicular to the light receiving surface 16A.
All the light that has entered 6 and has entered the light receiving portion 16 is reflected by the second reflecting surface 17. At this time, since the light receiving section 16 has a light receiving surface 16A having a convex arcuate cross-section with the bulb 6 as the focal point, the light becomes a parallel light beam on the light receiving surface 16A.
The light travels through 6 and is reflected by the second reflecting surface 17.

The light reflected by the second reflecting surface 17 travels through the light guide portion 18 toward the first reflecting surface 15, while the light reflected by the second reflecting surface 17 is substantially perpendicular to the plane portion 13. Since the angle of the second reflecting surface 17 is set so that the second reflecting surface 17 is rotated about the light source axis X as a base line, the cross section has an arc shape (inverse cone shape). , All the light reflected by the second reflecting surface 17 travels in parallel in the light guide portion 18.
Since the first reflection surface 15 is a flat surface, the light reflected here also travels in parallel in the flat surface portion 13 toward the third reflection surface 19 and is reflected by the third reflection surface 19 to indicate the pointer. Head to base 9 of 3. After that, the light is reflected by the pointer reflecting surface 20 and guided to the indicator 7 to make the indicator 7 brightly shine. FIG. 5 shows a path of light incident on the light guide 5. Light source to light receiving unit 1
The light directed toward the center of the thickness direction of 6 enters straight from the light receiving surface 16A and proceeds as indicated by a. The light traveling in the direction away from the center in the thickness direction is refracted at the light receiving surface 16A, and b,
Proceed as in c.

In this way, all the light traveling from the bulb 6 to the light receiving portion 16 is efficiently taken into the light receiving portion 16 and the second light is received.
Can be reflected by the reflective surface 17 of the second reflective surface 1
The light reflected at 7 can be efficiently guided to the first reflecting surface 15 as parallel rays. Further, by dividing the first reflecting surface 15, only the formation position of each dividing reflecting surface 15A is changed without changing the inclination angle of each dividing reflecting surface 15A (as shown in FIG. There is a step on 15)
Thus, the light reflected by the first reflecting surface 15 can be efficiently guided to the third reflecting surface 19. That is, the curved reflecting surface that may occur by rotating the bent portion 14 with the light source axis X as a base line is corrected, and the flat portion 13 is reflected by the first reflecting surface 15 without increasing the plate thickness more than necessary. The emitted light can be efficiently guided to the third reflecting surface 19 as parallel rays. In addition, the light reflected by the second reflecting surface 17 is substantially perpendicular to the flat surface portion 13 (that is, the light guide portion 18).
Since the plane portion 13 becomes substantially vertical), the angle of the second reflecting surface 17 is set, so that the light guide 5 and thus the pointer lighting device can be made compact.

6 and 7 show a second embodiment of the present invention. Since only the light guide 5 is different from that of the first embodiment, other detailed description will be omitted. In the present embodiment, the angle formed by the light reflected by the second reflecting surface 17 and the light reflected by the first reflecting surface 15 toward the third reflecting surface 19 (that is, the second reflecting surface). The light reflected on the surface 17 and the flat surface portion 13
Is 90 degrees or more and the light source axis X1 that is substantially parallel to the light reflected by the second reflecting surface 17 is used as a base line to form the bent portion 14 (the light receiving portion 16, the second reflecting surface 17, Light part 1
8) is rotated.

With this configuration, as in the first embodiment, the light receiving portion 16 (light receiving surface 16A) has an arc-shaped cross section rotated about the light source axis X1 as a base line. The light that radially travels from the light receiving section 16 to the light receiving section 16A enters the light receiving section 16 perpendicularly to the light receiving surface 16A without being reflected by the light receiving surface 16A, and all the light incident on the light receiving section 16 is reflected by the second reflecting surface 17. reflect. At this time, the light receiving unit 16
Is a light receiving surface 1 having a convex arcuate cross section with the bulb 6 as a focal point.
Since it has 6 A, the light becomes parallel rays on the light receiving surface 16 A, travels inside the light receiving portion 16, and is reflected by the second reflecting surface 17.

The light reflected by the second reflecting surface 17 travels through the light guide portion 18 toward the first reflecting surface 15, but the second reflecting surface 17 is reflected by the second reflecting surface 17. Since the cross section rotated about the light source axis X1 that is substantially parallel to the light is an arc shape (inverse conical shape), all the light reflected by the second reflecting surface 17 is made parallel in the light guide portion 18. move on. And the first
Since the reflecting surface 15 of is a flat surface, the light reflected here also travels in parallel in the flat surface portion 13 and can be efficiently guided to the pointer 3, so that the pointing portion 7 of the pointer 3 can be made brighter. I can. Further, since it is not necessary to make the angle formed by the light reflected on the second reflecting surface 17 and the flat surface portion 13 vertical (it is not necessary to make the light guide portion 18 and the flat surface portion 13 vertical), the bulb 6 The position can be set arbitrarily, and the degree of freedom in design can be increased.

In each of the above embodiments, the light receiving surface 1
Even if the light source is displaced with respect to 6A, the light receiving surface 16A has a convex arcuate cross section so that the light becomes parallel rays on the light receiving surface 16A and travels in the light receiving portion 16. In the case of No. 6, since it is not a point light source (the filament has a width), even if the light receiving surface 16A is a flat surface, most of the light from the bulb 6 enters the light receiving unit 16 perpendicularly to the light receiving surface 16A. Further, although the first reflecting surface 15 is a plane obtained by dividing into three, the plate thickness of the flat portion 13 is made thick so that all the light reflected by the first reflecting surface 15 is inside the flat portion 13 to the third reflecting surface 19. If it faces toward the side, the first reflecting surface 15 does not need to be divided. Further, even when dividing, the number of divisions is not limited to three.

Further, by making the light guide section 18 rotated about the light source axes X and X1 as a base line to have an arcuate shape (cylindrical shape), the thickness of the light receiving section 16 becomes uniform and the light guide section 18 is formed. Although it is easy and the light is allowed to go straight by suppressing the sink when molding the light guide body 5 which may occur when the plate thickness is uneven, all the light reflected by the second reflecting surface 17 is The shape of the light guide portion 18 may be arbitrarily set as long as it can be guided to the side of the first reflection surface 15.

[0025]

As the effects of the first and second aspects, the light incident from the light source to the light receiving portion of the light guide can be efficiently guided to the pointer to illuminate the pointer brighter.

With respect to the effects of the third and fourth aspects, it is possible to obtain the same effect as that of the invention of the first aspect while making the light guide body and thus the pointer illumination device compact.

As an effect described in claim 5, even if the angle formed by the light reflected by the second reflecting surface and the plane portion is an obtuse angle, the light reflected by the second reflecting surface is the light source axis. By being substantially parallel to, the light reflected by the second reflecting surface can be efficiently guided to the first reflecting surface, and further, the position of the light source can be arbitrarily set, increasing the degree of freedom in design. It is possible to obtain the same effect as the invention described in claim 1.

As an effect described in claim 6, since the light receiving portion is a light receiving surface having a convex arcuate cross section whose light source is substantially a focal point, light can be efficiently taken into the light receiving portion.
The light can be efficiently guided to the pointer to illuminate the pointer brighter.

The effect of claim 7 is that the first reflecting surface is a divided flat surface so that the light reflected by the second reflecting surface is efficiently reflected by the first reflecting surface, Three
It can be guided to the reflective surface of, and the pointer can be illuminated brighter.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a vehicle instrument to which a first embodiment of the present invention is applied.

FIG. 2 is a partial front view showing the light guide according to the same embodiment.

FIG. 3 is a partial rear view showing the light guide according to the same embodiment.

FIG. 4 is a partial perspective view showing a light guide according to the same embodiment.

FIG. 5 is a partial cross-sectional view (light path explanatory diagram) showing the light guide body of the same embodiment.

FIG. 6 is a partial cross-sectional view of a vehicle instrument to which the second embodiment of the present invention is applied.

FIG. 7 is a partial perspective view showing the light guide according to the same embodiment.

[Explanation of symbols]

3 guidelines 5 Light guide 6 bulbs (light source) 13 Plane 14 Bend 15 First reflective surface 16 Light receiving part 16A light receiving surface 17 Second reflective surface 18 Light guide X, X1 light source axis

Claims (7)

(57) [Claims] 1. A pointer, a flat portion for guiding the light of a light source to the pointer, and a bent portion, and a first portion between the flat portion and the bent portion.
A light guide having a reflecting surface, the bent portion includes a light receiving portion, a second reflecting surface that reflects light incident on the light receiving portion, and the light reflected by the second reflecting surface is the first reflecting surface. 1. A pointer illuminating device comprising: a light guide portion guided to one reflection surface, and the second reflection surface and the light receiving portion have an arcuate cross section rotated about a light source axis passing through the light source as a base line. apparatus. 2. A pointer, a flat portion for guiding light of a light source to the pointer, and a bent portion, and a first portion between the flat portion and the bent portion.
A light guide having a reflecting surface, the bent portion includes a light receiving portion, a second reflecting surface that reflects light incident on the light receiving portion, and the light reflected by the second reflecting surface is the first reflecting surface. 1. A pointer illuminating device comprising: a light guide portion that is guided to a reflection surface of 1. The bent portion has an arc-shaped cross section that is rotated about a light source axis passing through the light source as a base line. 3. The pointer illumination according to claim 1, wherein the second reflecting surface is provided so that the light reflected by the second reflecting surface is substantially perpendicular to the flat surface portion. apparatus. 4. The pointer illuminating device according to claim 1, wherein the light source axis is substantially perpendicular to the flat surface portion. 5. The pointer illumination device according to claim 1, wherein the light source axis is substantially parallel to the light reflected by the second reflecting surface. 6. The pointer illuminating device according to claim 1, wherein the light receiving section has a light receiving surface having a convex arcuate cross section with the light source as a substantially focal point. 7. The pointer illuminating device according to claim 1, wherein the first reflecting surface is a divided flat surface.