JPH03183912A - Light emission type analog meter - Google Patents

Abstract

PURPOSE:To eliminate an irregularity in the light quantity of a display pattern and to obtain the analog meter with high brightness by coupling the pointer shaft of a meter internal machine with a pointer while the shaft penetrates a reflector and a light diffusion plate, and irradiating the pointer and the back surface of a dial with back light obtained by reflecting the light from the discharge lamp by the reflector and passing the reflected light through the light diffusion plate. CONSTITUTION:The pointer shaft 11a penetrates respective shaft holes 12a, 13b, 16a, and 17c and runs under the cold cathode tube (discharge lamp) 14 to face the center of a pointer panel 18. The light from the cold cathode tube 14 is diffused by the light diffusion plate 16 and the light traveling to the reflec tor 13 is reflected by the reflecting surface 13a into nearly parallel light, which is diffused by the light diffusion plate 16. Consequently, the dial 17 and pointer panel 18 are irradiated with the uniform light from behind through the light diffusion plate 16 and only the scale, numbers, and part of a slit 18b illuminate and can be seen. Then when the pointer panel 18 is turned by the meter internal machine 11, the illuminating pointer (slit 18b) turns to makes an indication on the illuminating scale, thus making an analog display.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a light-emitting type analog meter in which the scale, characters, hands, etc. of the meter are made to emit light, and is particularly suitable for use as an on-vehicle analog meter. Concerning suitable luminescent analog meters.

[Conventional technology]

An example of this kind of light-emitting type analog meter is shown in FIG. 6.

This meter has a light guide plate 43 disposed between the meter internal unit 41 and the dial 42, and the light from the light source bulb 44 is taken in from the end 43a of the light guide plate 43 to enter the light guide plate 43 as shown by the arrow in the figure. By guiding the light guide plate 43 to emit light on the back surface of the dial 42, the light-transmitting scales formed on the dial 42 are made to emit light. Further, regarding the pointer 45, light is irradiated from the light guide plate 43 to the boss portion 45a of the pointer 45 through the periphery of the pointer shaft 41a.
It is designed to emit light by guiding and diffusing the light inside.

By lighting this type of luminescent analog meter at night, only the display pattern such as the scale, numbers, and pointer will glow in the dark, improving visibility and also offering excellent display quality. There is.

[Problem to be solved by the invention]

However, in the conventional light-emitting analog meter as described above, the light guide plate 43 is used to indirectly display the dial 4.
Since the light is irradiated onto the back surface of the display panel 2, there is a problem in that the brightness of the display pattern is low and the amount of light is uneven.

By the way, when a driver is dazzled by changes in outside light, such as when strong outside light such as sunlight enters through the windshield while driving during the day, or immediately after entering a tunnel, the driver's iris becomes smaller. Become. For this reason, the entire meter may appear dark and the visibility of the display may be reduced.

In order to prevent this decrease in visibility, it may be possible to increase the brightness of the display pattern, but the problem cannot be solved with the conventional meters because the amount of light is insufficient even if they are turned on during the day.

Note that as a light-emitting display device with relatively high luminance,
Although fluorescent display tubes and the like are used as in-vehicle meters, this type of display device is generally a digital display. However, analog meters are preferred by users, and it is desired to develop a light-emitting analog meter with a high brightness display pattern.

SUMMARY OF THE INVENTION An object of the present invention is to provide a light-emitting analog meter with high brightness and uniform light intensity in display patterns such as scales, characters, and hands.

[Means to solve the problem]

The light-emitting analog meter of the present invention, which was made to solve the above problems, has a pointer that emits light by backlighting, a dial whose scale part emits light by backlighting, and a light diffusing plate arranged on the back of the pointer and dial. a reflector having a concave reflective surface facing the back surface of the light diffusing plate; a discharge lamp disposed as a light source between the light diffusing plate and the reflector at or near the focal point of the reflector; a meter internal unit disposed behind the reflector, a pointer shaft of the meter internal unit is connected to the pointer through the reflector and the light diffusing plate, and the light from the discharge lamp is connected to the pointer shaft. It is characterized in that the backlight reflected by the reflector and passed through the light diffusing plate is irradiated onto the hands and the back surface of the dial.

[For production]

In the light-emitting analog meter of the present invention, the pointer is rotated by the meter internal unit via a pointer shaft passing through the reflector and the light diffusing plate. Further, the light from the discharge lamp is reflected by the reflex reflector and diffused by the light diffusion plate, and this diffused light is directly irradiated as a backlight to the hands and the back of the dial, causing the hands and scale to emit light. Display light can be obtained.

Therefore, the dial and the back surface of the hands are illuminated with high brightness and uniform light, increasing the brightness of display patterns such as scales, letters, hands, etc.

〔Example〕

FIG. 1 is a partial sectional view of a light-emitting analog meter according to an embodiment of the present invention, FIG. 2 is a partial front view thereof, and FIG. 3 is an exploded perspective view thereof.

In the figure, reference numeral 11 denotes a meter internal mechanism that rotates a pointer shaft 11a in response to an electric signal input from a circuit not shown, and its internal structure is similar to that of a conventionally known analog meter. 12 is the pointer shaft 1 of the meter internal unit 11
Case body arranged on the front side of 1a, 13 is case body 12
The cylindrical concave irregular surface 13a is housed in the case body 1.
2 is a reflector facing the opening side, 14 is a reflector
Cold cathode tubes (discharge lamps) arranged along the focal point f of 13
The cold cathode tube 14 is connected to an external power source via a socket 15 and a lead wire (not shown) drawn out from the case body 12, and constitutes a high-output light source. Incidentally, since the reflector 13 forms a concave mirror by the cylindrical concave irregular surface 13a, the focal point f becomes a straight line as shown in FIG.

16 is a light diffusing plate disposed to cover the opening of the case body 12; 17 is a dial disposed on the front surface of the light diffusing plate 16;
1B is a disc-shaped pointer plate arranged on the front side of the dial 17, and the center of this pointer plate 18 is fixed to the tip of the pointer shaft 11a.

As shown in FIG. 2, the dial 17 has a black face surface 17a (shaded portion) formed by printing black on a transparent resin plate, and the scale and number portions 17b are cut out characters. The scale and number portions and the circular portion overlapping with the pointer plate 18 are made transparent. In addition, the pointer plate 18 has a black face surface 18a (hatched portion) formed by black printing on a disk-shaped transparent resin plate, and by not printing a part of the black face surface 18a in the radial direction from the vicinity of the center, the light transmittance is improved. Swan) 18b is formed, and this slit 18b serves as a pointer.

Note that the scale and number portion 17b and the swan 18b as described above can also be formed by punching using a light-opaque member.

Incidentally, in general, in-vehicle analog meters do not have scales formed around the entire circumference, but are often formed approximately in the range from 8 o'clock to 4 o'clock clockwise on a clock face.

The scale of the dial 17 in this embodiment is not formed all around the circumference as shown in FIG. 2, but the center of the pointer plate 18 is placed a certain distance d below the center of the height H of the scale. It is set in the wrong position. Further, as shown in FIG. 1, the height of the reflective surface 13a of the reflector 13 is the height H of the scale portion.
Further, the center thereof and the position of the cold cathode tube 14 are aligned with approximately the center P of the height H of the scale portion. Corresponding to the center of the pointer plate 18, the dial 17, light diffusing plate 16, reflector 13, and case body 12 have small diameter shaft holes 17c, 16a,
13b and 12a are formed respectively, and the pointer shaft 11
a passes through each of the shaft holes 12a, 13b, 15a, and 17c, passes under the cold cathode tube 14, and is directed toward the center of the pointer plate 18.

With the above configuration, the light from the cold cathode tube 14 is diffused by the light diffusing plate 16, and the light directed toward the reflector 13 is reflected by the reflecting surface 13a into substantially parallel light, which is then diffused by the light diffusing plate 16. And the light diffusing plate 16
Uniform and bright light is illuminated behind the dial 17 and the pointer plate 18, and only the scale, numbers, and swan 18b appear to be illuminated, and when the pointer plate 18 is rotated by the meter internal unit 11, , luminous pointer (slit 18
b) rotates to indicate the luminous scale, and analog display is performed.

In the light-emitting analog meter of the above embodiment, the dial 17
Although a slight clearance is provided between the pointer plate 18 and the pointer plate 18, light leakage may occur from this clearance. Although this light leakage is hardly visible from the front, in order to reduce this light leakage, it may be done as shown in FIG. 4, for example.

The light emitting type analog meter shown in the same figure has a different configuration of the dial and pointer plate from the configuration shown in FIG. The pointer plate 18' is set to 0 so that the pointer plate 18' is disposed at In FIG. 4, the same parts as in FIG. 3 are given the same reference numerals.

An opening 170' is formed in the part of the dial 17' facing the pointer plate 18', and the area around it is covered with black letters with the scale and number part 17b' cut out, as in FIG. A face surface 17a' is formed. Also, like the pointer plate 18, the pointer plate 18' has a slit 18b' formed in the black face surface 18a'.

Around the opening 17c' of the dial 17', a stepped portion 17d' is formed on the pointer plate 18' side (light diffusing plate 16 side), as shown in the cross section in FIG. The periphery of the pointer plate 18' is loosely fitted into the portion, and a certain amount of clearance is provided. This makes it possible to reduce light leakage from the clearance between the dial 17' and the pointer plate 18'.

〔Effect of the invention〕

As explained above, according to the present invention, a light diffusion plate, a discharge lamp, a light diffusion plate, and a meter internal unit are arranged in this order on the back of the pointer and dial, and the discharge lamp is arranged as a reflector.
The pointer shaft of the meter is connected to the pointer by passing through the reflector and the light diffusing plate.
The light from the discharge lamp is reflected by a reflector, and the backlight that passes through the light diffuser is illuminated on the hands and the back of the dial.
Since it is configured as a light-emitting analog meter, the light from the discharge lamp is reflected by the pointer and the back of the dial.
The light is directly irradiated as a backlight by the light diffusing plate, so that there is no unevenness in the amount of light displayed in display patterns such as scales, letters, hands, etc., and it is possible to obtain a light-emitting analog meter with high brightness.

[Brief explanation of drawings]

Figure 1 is a partial cross-sectional view of the light-emitting analog meter in the example, Figure 2 is a partial front view of the light-emitting analog meter, Figure 3 is an exploded perspective view of the light-emitting analog meter, and Figure 4 is an exploded perspective view of the light-emitting analog meter. FIG. 5 is a sectional view of the same embodiment, and FIG. 6 is a diagram showing an example of a conventional light-emitting analog meter. 11...Meter internal unit, lla...Pointer shaft, 13.
...Reflector-14...Cold cathode tube, 16...Light diffusion plate, 17.17'...Dial, 1B, 1B'...
Guidance board.

Claims (3)

[Claims] (1) A pointer that emits light due to the backlight, a dial whose scale portion emits light due to the backlight, a light diffusing plate placed on the back of the hands and dial, and a concave reflective surface facing the back of the light diffusing plate. a reflector; a discharge lamp disposed as a light source between the light diffusion plate and the reflector at or near the focal point of the reflector; and a meter internal unit disposed behind the reflector; The pointer shaft of the internal meter is connected to the pointer by passing through the reflector and the light diffusing plate, and the light from the discharge lamp is reflected by the reflector so that the backlight passing through the light diffusing plate is connected to the pointer and the letters. A light-emitting analog meter characterized by illuminating the back of the board. (2) The pointer is a disc-shaped pointer plate having a disc-shaped light-impermeable surface with a light-transmitting slit formed from near the center toward the outer periphery, and the dial is a scale portion thereof. is made optically transparent and has a circular optically transparent part matching the circular shape of the pointer plate on the inner peripheral side of the scale part,
2. The light-emitting analog meter according to claim 1, wherein the pointer plate is arranged in alignment with the front surface of the circular portion, and the pointer shaft is connected to the center of the pointer plate. (3) The pointer is a disc-shaped pointer plate having a disc-shaped light-impermeable surface with a light-transmitting slit formed from near the center toward the outer periphery, and the dial is a scale portion thereof. is made light-transmissive, and has a light-transmissive opening portion on the inner peripheral side of the scale portion, the diameter of which is slightly smaller than that of the pointer plate, and the periphery of the opening portion overlaps the periphery of the pointer plate. 2. The light-emitting analog meter according to claim 1, wherein said pointer plate is disposed at the center of said pointer plate, and said pointer shaft is connected to the center of said pointer plate.