JP2000018976A - Illumination structure for meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination structure for meters, wherein the meter can be flattened by thinning it and a dial can be efficiently illuminated by guiding a light of a light source efficiently to a light guide plate. SOLUTION: This illuminating structure for meters comprises a dial 2 having letters, scale divisions or figure as a light-permeable part on the top surface, and a light guide plate 3 disposed below the dial 2 for guiding an illuminating light to the dial and illuminates by irradiating a light from a light emitting diode 9 on the dial 2 from its back side, through the light guide plate 3. A recess 3a for the light source is formed like a pit into the light guide plate 3, and the light emitting diode 9 is disposed in the recess 3a for the light source.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a speedometer for a vehicle,
The present invention relates to an illumination structure of an instrument used for an instrument such as a tachometer and for illuminating a dial of the instrument from a back side through a light guide plate.

[0002]

2. Description of the Related Art Conventionally, as a lighting structure for a dial of an instrument such as a speedometer or a tachometer for a vehicle, a light guide plate is attached to the lower surface of the dial and a light emitting diode disposed below the light guide plate emits light. Japanese Patent Application Laid-Open No. 9-2165 discloses a structure in which the light is introduced into a light guide plate, and the light in the light guide plate is emitted and illuminated from characters, scales, etc., which are printed on the dial so as to be able to transmit light.
No. 5 proposes this.

[0003]

However, in the illumination structure of the above-mentioned instrument, a light guide plate is attached to the lower surface of the dial, a casing is attached below the light guide plate, and a space is provided below the casing. The printed circuit board is mounted on the printed circuit board, and the light emitting diode is disposed upward on the printed circuit board. Light emitted from the light emitting diode is introduced into the light guide plate, and the dial is illuminated by the light guide plate.

[0004] Therefore, in the above-mentioned instrument, since the light emitting diodes are arranged at intervals below the light guide plate and below the casing, the thickness of the instrument increases and the instrument can be miniaturized. There was a problem that was hindered. Further, since the distance between the light emitting diode and the light guide plate is widened, there is a problem that the efficiency of the light emitted from the light emitting diode to the light guide plate is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it has been made possible to reduce the thickness of an instrument so that the instrument can be flattened, and to efficiently introduce light from a light source into a light guide plate to illuminate a dial. It is an object of the present invention to provide a lighting structure of an instrument capable of efficiently performing the measurement.

[0006]

In order to achieve the above object, a lighting structure according to a first aspect of the present invention comprises a dial having a character, a scale, or a figure provided on a top surface thereof as a light-transmitting portion; A light guide plate arranged below the light guide plate to guide the illumination light to the dial, and a lighting structure of an instrument for illuminating the dial with light from a light source through the light guide plate and illuminating the dial from the back, A light source concave portion is formed in a concave shape from the lower surface side, and the light source is disposed in the light source concave portion.

The illumination structure of the meter according to the second aspect of the present invention is characterized in that a dial having characters, scales, or figures on its upper surface as a light-transmitting portion and a dial disposed below the dial to provide illumination light to the dial. A light guide plate for guiding the light from the light source to the dial through the light guide plate to illuminate the dial from the back surface. A reflecting surface inclined with respect to the upper surface is formed on a lower surface of the light plate, and a light source is disposed to face an incident portion on a side surface of the light guide plate.

Here, in the lighting structure of the first aspect, a printed board on which the light source is mounted can be attached to the lower surface of the light guide plate.

In the illumination structure of the present invention, a printed circuit board can be mounted on the lower surface of the light guide plate, and a light source can be mounted on the printed circuit board so as to emit light in a lateral direction.

In the illumination structure of the first aspect, a substantially spherical concave surface can be formed above the concave portion for the light source provided on the light guide plate.

Further, in the illumination structure according to the second aspect, the light guide plate may be formed in a substantially arc shape along the scale of the dial, and light sources may be disposed opposite to both ends of the substantially arc light guide plate. it can.

[0012]

In the lighting structure of the instrument having such a configuration, when the light source is turned on, light emitted from the light source enters the light guide plate from inside the light source recess, passes through the light guide plate, and passes through the light guide plate. Light is radiated to the front side of the meter from the translucent part of the character, scale, or figure on the dial attached to the upper surface of the dial, and the characters, scale, and indicator are illuminated from the back side, and rise Is displayed as follows.

At this time, since the light source is disposed in the light source recess formed in the light guide plate, and the light emitted from the light source can be made to enter the light guide plate with high efficiency, a sufficient amount of illumination is provided. It is possible to illuminate and display characters, scales, or indicators with light. In addition, since the gap in the thickness direction for disposing the light source and the gap between the light guide plate and the light source, which were conventionally required, can be eliminated, the structure of the instrument can be made thinner and the instrument can be flattened. it can.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a front view of an automobile speedometer and an instrument provided with a rotary type, and FIG. 2 shows a partially enlarged sectional view thereof. 1 is a meter case, and meter case 1
The light guide plate 3 is mounted on the light guide plate 5 via the light source printed circuit board 5, and the dial 2 is mounted on the light guide plate 3. The dial plate 4 covers the periphery of the dial 2 so as to cover the periphery. Attached to.

The dial 2 is placed on a thin transparent synthetic resin plate.
Parts other than the characters, scales and figures are printed with light-shielding paint so that the characters, scales and figures (indicators) are translucent. The light guide plate 3 is formed in a plate shape from a transparent synthetic resin such as acrylic or polycarbonate, and a light source concave portion 3 a is formed in a concave shape from the lower surface side at an arbitrary position on the dial 2 to be illuminated. For example, when illuminating the characters on the dial 2, that is, the characters 0, 20, 40,... 180 and the scale, the light source concave portion 3 a is located below the portion corresponding to each character (0 to 180). It is formed.

These light source recesses 3a are formed slightly larger than the light emitting diode 9 as a light source inserted therein, and a substantially spherical concave surface is formed on the ceiling (upper surface) of the light source recess 3a. Is done. The concave surface of the ceiling is determined by calculating a curvature or the like so that light is most efficiently introduced into the light guide plate 2 when the light emitting diode 9 is disposed in the light source concave portion 3a and light is emitted.

Each light emitting diode 9 disposed in the light source recess 3a is surface-mounted on the light source printed circuit board 5, and the light source printed circuit board 5 is sandwiched between the light guide plate 3 and the meter case 1. The end of the light source printed circuit board 5 is connected to a drive / control printed circuit board 10 via an FPC 11.

At the center of the dial 2, the light guide plate 3, and the meter case 1 corresponding to the axis of the meter, a hole for a pointer shaft is formed, and a movement 6 of the meter is mounted on a mounting portion formed below the hole. It is attached. As the movement 6, for example, a cross-coil inner machine is used, and the base of the pointer 8 is fitted to the tip of the pointer shaft 7 from above. The printed circuit board 10 is attached to the lower side of the movement 6, and a circuit for driving and controlling the movement is mounted.

Further, the light guide plate 13 is attached to the lower surface of the dial 12 and the light source printed circuit board 15 is disposed below the light guide plate 13 in the indicator portion of the meter, similarly to the meter portion. (Fig. 3). The dial 12 is printed with a light-shielding paint on portions other than the indicator so that an indicator (graphic) of a parking brake and an indicator (graphic) of a battery voltage are formed as light transmitting portions on a thin transparent synthetic resin plate. It is formed.

As described above, the light guide plate 13 is formed in a plate shape from a transparent synthetic resin, and a concave portion 13a for a light source is formed in a concave shape from a lower surface at a position corresponding to an indicator to be illuminated. The light emitting diode 19 is mounted in the light source concave portion 13 a so as to be inserted from below while being mounted on the light source printed circuit board 15.

In the lighting structure of the instrument configured as described above, when the light emitting diodes 9 and 19 are turned on, the light emitted from the light emitting diodes 9 and 19 emits light to the light source recesses 3a and 1a.
The light enters the light guide plates 3 and 13 from the inside of the light guide plates 3 and 13
, Light is radiated to the front side of the meter from the characters, scales, or translucent portions of the indicators (graphics) on the dials 2 and 12 attached to the upper surface of the light guide plate, and the characters, scales and indicators Is illuminated from the back side, so that it is displayed in a floating manner.

At this time, the light emitting diodes 9 and 19 serving as light sources are disposed in the light source recesses 3a and 13a formed in the light guide plates 3 and 13, and light emitted from the light emitting diodes 9 and 19 is provided. Since the light can enter the light guide plates 3 and 13 with high efficiency, it is possible to satisfactorily illuminate and display characters, scales, or indicators with a sufficient amount of illumination light.

In addition, the gap in the thickness direction for disposing the light emitting diode (light source) and the gap between the light guide plate and the light source, which have been conventionally required, can be eliminated. Can be flattened.

4 and 5 show another embodiment. FIG. 4 is an enlarged sectional view of a meter portion corresponding to FIG. 2, and FIG. 5 is an enlarged sectional view of an indicator portion corresponding to FIG. In this embodiment, instead of the light guide plate 3, small light guide plates 23 are attached to the lower surface of the dial 2, that is, below the illuminated characters and scales.

The light guide plate 23 has a light incident portion 23 on the side surface.
is formed, and the lower surface thereof is inclined with respect to the upper surface, whereby the reflection surface 23 that reflects the light incident from the incident portion 23a is formed.
Provided as b. A light emitting diode 29 that emits light in the lateral direction (side) is mounted on the light source printed circuit board 5 disposed below the light guide plate 23 so as to face the incident portion 23a.

In the indicator section shown in FIG. 5, similarly to the above, instead of the light guide plate 13 of FIG.
Reference numeral 3 is attached to the lower surface of the indicator (figure) of the dial 2, that is, below the illuminated graphic part. This light guide plate 33 also
Similarly to the above, the light incident portion 33a is formed on the side surface, and the lower surface thereof is inclined with respect to the upper surface.
It is provided as a reflection surface 33b that reflects light incident from the light source.
In addition, a light emitting diode 39 that emits light in the lateral direction (side) is mounted on the light source printed circuit board 15 disposed below the light guide plate 33 so as to face the incident portion 33a.

In this lighting structure, as described above,
When the light emitting diodes 29 and 39 are turned on, the light emitted from the light emitting diodes 29 and 39 is transmitted to the incident portions 23a and 33.
a, the light enters the light guide plates 23 and 33, is reflected by the reflection surfaces 23b and 33b on the lower surface thereof, proceeds to the dials 2 and 12 from the upper surface of the light guide plate, and transmits the characters, scales, or indicators (graphics). Light is emitted from the light unit to the front side of the meter, and letters, scales, and indicators are illuminated from the back side, so that the display is raised.

At this time, the light-emitting diodes 29 and 39 serving as light sources are arranged to face the light-entering portions on the side surfaces of the light guide plates 23 and 33, so that the light emitted from the light-emitting diodes 29 and 39 can be efficiently emitted. The characters, scales, or indicators can be satisfactorily illuminated and displayed with a sufficient amount of illuminating light that can be made to enter the light guide plates 23 and 33.

As described above, the light emitting diode 29,
By arranging the light guides 39 in opposition to the light-entering portions on the side surfaces of the light guide plates 23 and 33, similarly to the above, the gaps in the thickness direction for arranging the light-emitting diodes (light sources) conventionally required and the light guide plates are provided. The gap between the light source and the light source can be eliminated, the structure of the instrument can be made thinner, and the instrument can be flattened.

FIG. 6 shows still another embodiment. In this embodiment, the light guide plate 43 is formed in a shape in which a part of a ring is cut off, that is, in an arc shape. Incident portions 43a are formed on two end surfaces (side surfaces) of the arcuate light guide plate 43, and the lower surface of the light guide plate 43 is inclined upward toward the center,
It is a reflecting surface that reflects light incident from the incident part 43a.

Similarly to the above, a light emitting diode 29 that emits light in the lateral direction (side) is provided opposite to the light incident portion 43a. 5 and mounted. Although not shown, a dial similar to that of FIG. 1 is mounted on the light guide plate 43, and characters and scales on the dial are arranged on the light guide plate 43. Even in such a structure, similarly to the above, the gap in the thickness direction for disposing the light emitting diode (light source) and the gap between the light guide plate and the light source, which were conventionally required, can be eliminated.
The structure of the instrument can be made thinner and the instrument can be flattened.

In the above embodiment, a light emitting diode is used as a light source, but an EL element, a discharge tube or the like may be used.

[Brief description of the drawings]

FIG. 1 is a front view of a vehicle instrument showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along the line II-II of FIG.

FIG. 3 is an enlarged sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an enlarged sectional view corresponding to FIG. 2 of another embodiment.

FIG. 5 is an enlarged sectional view corresponding to FIG. 3 of another embodiment.

FIG. 6 is a perspective view of a light guide plate 43 of still another embodiment.

[Explanation of symbols]

 2,12-Dial 3,13,23,33,43-Light guide plate 3a-Recess for light source 23a, 33a, 43a-Injection part 9,19,29,39-Light emitting diode

Claims (6)

[Claims] A dial provided with a character, a scale, or a figure as a light transmitting portion on an upper surface thereof; and a light guide plate disposed below the dial and guiding illumination light to the dial. In a lighting structure of an instrument for irradiating light from a light source to the dial through the light guide plate to illuminate the dial from the back surface, a light source recess is formed in the light guide plate in a concave shape from the lower surface side,
An illumination structure for an instrument, wherein a light source is provided in the light source recess. 2. A dial having a character, a scale, or a figure as a light transmitting portion on an upper surface thereof, and a light guide plate disposed below the dial to guide illumination light to the dial, In a lighting structure of an instrument for illuminating the dial with light from a light source through the light guide plate to illuminate the dial from the back, a light incident portion is formed on a side surface of the light guide plate, and a lower surface of the light guide plate. A reflecting surface inclined with respect to an upper surface of the light guide plate, and a light source disposed opposite to an incident portion on a side surface of the light guide plate. 3. The illumination structure for an instrument according to claim 1, wherein a printed circuit board on which said light source is mounted is attached to a lower surface of said light guide plate. 4. The instrument according to claim 2, wherein a printed circuit board is attached to a lower surface of the light guide plate, and the light source is mounted on the printed circuit board so as to emit light in a horizontal direction. Lighting structure. 5. The illumination structure for an instrument according to claim 1, wherein a substantially spherical concave surface is formed above the light source concave portion. 6. The instrument according to claim 2, wherein the light guide plate is formed in a substantially arc shape along the scale of the dial, and the light source is disposed opposite to both ends of the substantially arc light guide plate. Lighting structure.