JPH1030941A - Pointer measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pointer measuring instrument in which the entire surface excluding the graduation and character parts of a dial can be made to emit light uniformly and assembly working efficiency is improved. SOLUTION: The pointer measuring instrument has a light-guiding plate 5 adhered to the reverse side of a dial 3, a cold-cathode tube 6 of straight pipe type being mounted to one edge of the light-guiding plate 5, and a reflection frame 9 for covering the rear surface of the light-guiding plate 5 and the cold- cathode tube 6. The dial 3 is made of a transparent resin sheet, a graduation and character part 3a is formed by a non-transmission material, and a reflection sheet 10 is provided at the reflection frame 9. A slit 14 for dimming light or an impression 15 is formed on the light-guiding plate 5, a light diffusion sheet 21 is applied to the surface of the side of the dial 3, a reflection surface 5d for reflecting light to a needle 13 is formed at a needle shaft insertion hole 5a, and light of the cold-cathode tube 6 is guided to the light-guiding plate 5 and an entire surface excluding a graduation/character part 3a of the dial 3 and the needle 13 are allowed to emit light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointer instrument such as a combination meter for a vehicle, and more particularly to an improvement in a dial illuminating device for displaying a pointer.

[0002]

2. Description of the Related Art FIG. 5 shows a combination meter which is a conventional pointer instrument. A facing 2 is attached to the front of the meter case 1, and a dial 3 is attached to the rear of the facing 2.
However, a transparent panel 4 is attached to the front part.
A light diffusion plate 20 is attached to the back surface of the dial 3.

[0003] In the meter case 1, an inner machine 11 for hands is provided, and a pointer shaft 12 protrudes from the front surface of the dial 3.
A pointer 13 is attached to the tip. Meter case 1
A ring-shaped cold-cathode tube 6 is attached to the rear part, and a light emitting diode (LED) 30 housed in a case is attached around the pointer shaft 12.

When the cold-cathode tube 6 is turned on, light is guided to the light diffusing plate 20 so that the graduation / character portion 3a of the dial 3 emits light. It is supposed to.

[0005]

In the above-mentioned conventional pointer instrument, the cold-cathode tube 6 has a ring shape, and the cold-cathode tube 6
Since there is the inner unit 11 between the light source and the light diffusing plate 14, the periphery of the dial 3 where the cold cathode tubes 6 are present is strong, and the center where the inner unit 11 is present is weakly illuminated. It is difficult to emit light uniformly.

Further, there is another problem that a dedicated LED 30 is required to emit the pointer 13 and the assembling work of the LED 30 is troublesome.

The present invention has been made in view of the above points, and provides a pointer instrument capable of emitting light uniformly over the entire surface of the dial plate except for the scale and the character portion and having improved assembling workability. The purpose is to do.

[0008]

In order to achieve the above object, the present invention is directed to a light guide plate closely attached to the back of a dial and a straight pipe type attached to one edge of the light guide plate. A pointer instrument comprising: a cold cathode tube; and a reflection frame that covers the back surface of the light guide plate and the cold cathode tube, and illuminates the dial and hands on the dial with the cold cathode tube. , The dial is formed of a transparent resin sheet, a scale and a character portion are formed of an opaque material, and a reflection sheet is provided on a surface of the reflection frame on the light guide plate side; A slit or a grain for dimming is formed on the back surface, and a light diffusing sheet is attached to the surface on the dial side, and the light is reflected to the pointer through the pointer shaft insertion hole. Characterized in that a reflective surface is formed It is.

Therefore, according to the first aspect of the present invention, when the cold cathode fluorescent lamp is turned on, light is guided to the light guide plate to cause the dial to emit light. The cold-cathode tube is a straight tube type, and the entire surface of the dial is illuminated using a light guide plate.There is no obstruction between the cold-cathode tube, which is the illumination light source, and the dial. Can emit light substantially uniformly over the entire surface of the device.

[0010] In addition, since the entire surface of the dial plate emits light except for the scale and the character portion, light emission with high luminance and high contrast is obtained, whereby the display can be clearly recognized.

The light introduced into the light guide plate can be efficiently reflected toward the dial by the reflection sheet provided on the reflection frame.

Further, light directed from the light guide plate toward the dial can be modulated by slits or embosses, and can be diffused by the light diffusion sheet to uniformly emit the dial.

Further, the light introduced into the light guide plate is reflected by a reflection surface provided in the pointer shaft insertion hole of the light guide plate, so that the pointer can emit light.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. The same members and the same functions as those in FIG. 5 are denoted by the same reference numerals.

In FIG. 1, a dial 2 is attached to the front of the meter case 1 and a dial 3 is attached to the rear of the dial 2.
However, a transparent panel 4 is attached to the front part.
The dial 3 has a configuration in which a transparent resin sheet is used, the scale / character portion 3a is a light non-transmitting portion, and the other portions are a transmitting portion.

A light guide plate 5 is attached to the back of the dial 3. This light guide plate 5, as shown in FIG.
A pointer shaft insertion hole 5a is formed at several places, and a straight tube type cold cathode tube 6 is attached to the upper edge thereof. A connector 8 is connected to the cold cathode tube 6 via an electric wire 7.

A reflection frame 9 is attached to the back surface of the light guide plate 5, and the back surface and the outer periphery of the light guide plate 5 and the cold cathode tube 6 are held by the reflection frame 9. A reflection sheet 10 is attached to a surface of the reflection frame 9 on the light guide plate 5 side. The reflection frame 9 is formed of a synthetic resin material, and is configured by attaching a reflection sheet 10 to the inner surface to increase the reflectance.

The light guide plate 5 has a slit or a grain for light control formed on the back surface thereof, and a light diffusion sheet 21 is attached to the surface on the dial 3 side.

As shown in FIG. 3, the slit 14 or the grain 15 is formed on the back surface of the light guide plate 5 on the side opposite to the dial 3, and the light is controlled by the density thereof, and is close to the cold cathode tube 6. It is possible to prevent uneven light emission of the dial 3 which becomes brighter in a portion. And these slits 14 or grain 15
Are formed on portions (parts shown by oblique lines in FIG. 4) of the light guide plate 5 except for the respective portions 5b and 5c of the light guide plate 5 corresponding to the scale portion and the character portion, respectively, as shown in FIG. The entire surface of the dial 3 excluding the character portion is formed so as to be uniformly illuminated.

The light diffusing sheet 21 diffuses light from the light guide plate 5 toward the dial 3 so that the entire surface of the dial 3 emits light uniformly.

An inner machine 11 for a pointer is provided in the meter case 1, and its pointer shaft 12 is formed in the pointer shaft insertion hole 5 of the light guide plate 5.
The dial 13 protrudes from the front surface of the dial 3 and has a pointer 13 attached to the tip. The light guide plate 5 is inserted into the pointer shaft insertion hole 5a.
A reflection surface 5d for reflecting the light introduced to the pointer 13 to the pointer 13 is formed. The pointer 13 is configured to emit light by light reflected by the reflection surface 5d.

Next, the operation of the above configuration will be described.

When the cold-cathode tube 6 is turned on, the light guided to the light guide plate 5 is dimmed by the slit 14 (or the grain 15), and is reflected by the reflecting frame 9 and the reflecting sheet 10.
The light is reflected to the side and diffused by the light diffusion sheet 21 to reach the dial 3. Since the dial 3 has a transmissive portion other than the scale / character portion 3a, the transmissive portion emits light, and the scale / character portion 3a does not emit light. The pointer 13 also emits light at the same time.

As described above, in the present embodiment,
The cold cathode tube 6 is a straight tube type, and the light guide plate 5 is used to emit light over the entire surface of the dial 3 except for the scale and the character portion 3a. There is no blockage in between, so that the entire surface of the dial 3 can emit light uniformly.

Further, since the entire surface of the dial 3 excluding the scale / character portion 3a emits light, high-luminance, high-contrast light is obtained, whereby the display can be clearly recognized.

By providing the reflection sheet 10 on the surface of the reflection frame 9 on the light guide plate 5 side, the light introduced into the light guide plate 5 can be efficiently reflected by the reflection sheet 10 toward the dial 3. Therefore, the higher brightness and higher contrast can be further emphasized.

The light introduced into the light guide plate 5 is dimmed by the slit 14 or the grain 15 formed in the light guide plate 5 and the light diffusion sheet 21 attached to the surface of the light guide plate 5 on the dial 3 side. The light emission of the dial 3 can be further uniformed by being diffused.

Further, since the pointer 13 is configured to emit light together with the dial 3 by the light of the cold cathode tube 6 introduced into the light guide plate 5, a light source dedicated to the pointer 13 (for example, the LED 3 shown in FIG. 5)
0) becomes unnecessary, and the assembling workability can be improved.

The dial 3 can be illuminated with various illumination colors by changing the cold-cathode tube 6 to one having a different emission color.

[0030]

As described above in detail, according to the first aspect of the present invention, the cold-cathode tube is of a straight tube type, and the entire surface of the dial except for the graduation and the character portion is illuminated using a light guide plate. As a result, there is no obstruction between the cold-cathode tube, which is the illumination light source, and the dial, so that the entire surface of the dial can emit light substantially uniformly.

Since the dial plate emits light over the entire surface except for the scale and the character portion, the dial plate emits light with high luminance and high contrast, whereby the display can be clearly recognized.

Also, since the reflection sheet is provided on the reflection frame,
The light introduced into the light guide plate can be efficiently reflected toward the dial by the reflection sheet, and thereby the above-described high brightness and high contrast can be further emphasized.

Further, light directed from the light guide plate toward the dial is dimmed by a light control slit or grain formed on the back surface of the light guide plate and a light diffusion sheet adhered to the light guide plate.
In addition, the dial is diffused, so that the dial can emit light uniformly.

Further, since the pointer is configured to emit light together with the dial by the light of the cold cathode tube introduced into the light guide plate,
Since a light source dedicated to the pointer is not required, the assembling workability can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of a pointer instrument of the present invention.

FIG. 2 is a front view of a portion of a light guide plate and a cold cathode tube used in the pointer instrument of the embodiment.

FIG. 3 is a cross-sectional view illustrating a main part of the light guide plate shown in FIG.

FIG. 4 is a plan view illustrating a formation state of a slit or a grain of the light guide plate of FIG. 2;

FIG. 5 is a vertical sectional side view of a conventional pointer instrument.

[Explanation of symbols]

 REFERENCE SIGNS LIST 3 dial plate 3a scale / character portion 5 light guide plate 5a pointer shaft insertion hole 5d reflective surface 6 cold cathode tube 9 reflective frame 10 reflective sheet 13 pointer 14 slit 15 texture 21 light diffusion sheet

Claims (1)

[Claims] 1. A light guide plate closely attached to the back surface of a dial, a straight-tube type cold cathode tube attached to one end of the light guide plate, and a reflection covering the back surface of the light guide plate and the cold cathode tube. A dial and an indicator instrument for illuminating the dial and the hands on the dial with the cold-cathode tube, wherein the dial is formed of a transparent resin sheet, and a scale / character portion is not formed. A light-transmitting material, a light-reflecting sheet is provided on a surface of the reflection frame on the light guide plate side, and a light control slit or embossment is formed on the back surface of the light guide plate. A pointer meter, wherein a light diffusing sheet is attached to the dial-side surface, and a reflecting surface for reflecting light to the pointer is formed in the pointer shaft insertion hole.