JPH0749974B2 - Luminous analog meter - Google Patents

Description

TECHNICAL FIELD The present invention relates to a light-emitting analog meter in which the scale, characters, pointers, etc. of the meter are made to emit light, and particularly for use as a vehicle-mounted analog meter. The present invention relates to a suitable light emitting analog meter.

[Conventional technology]

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

In this meter, a light guide plate 43 is arranged between the meter internal unit 41 and the dial 42, and the light from the light source bulb 44 is directed to the end portion of the light guide plate 43.
By taking in from 43a and guiding it into the light guide plate 43 as shown by the arrow in the figure, and causing the light guide plate 43 to emit light on the back surface of the dial 42, the light-transmissive scale and the like formed on the dial 42 can be made to emit light. It was done. Regarding the pointer 45, the boss portion 45a of the pointer 45 is passed from the light guide plate 43 around the pointer shaft 41a.
The light is radiated to the hands to guide the light in the pointer 45 and emit light by light diffusion.

By turning on this type of light-emitting analog meter at night, visibility is improved because only the display pattern such as scales, numbers, and pointers appears to emit light in the dark, and it is also excellent in display quality. There is.

[Problems to be Solved by the Invention]

However, in the conventional light-emitting analog meter as described above, since the light guide plate 43 is used to indirectly irradiate the back surface of the dial 42, the brightness of the display pattern is low and the light amount is uneven. There is a problem that occurs.

By the way, when strong external light such as sunlight enters the windshield while driving the vehicle during the daytime or immediately after entering a tunnel, when the driver is dazzled by changes in external light, the iris of the driver becomes small. Become. Therefore, the entire meter may appear dark and the visibility of the display may deteriorate.

In order to prevent this decrease in visibility, it is conceivable to increase the brightness of the display pattern, but the above-mentioned conventional meter cannot solve the problem because the amount of light is insufficient even when the meter is turned on during the day.

In addition, as a light emitting type display device with relatively high emission brightness,
Fluorescent display tubes and the like are used as in-vehicle meters, but this type of display device is generally a digital display. However, an analog meter is also favored as a user-oriented product, and development of a light-emitting analog meter with high display pattern brightness is desired.

It is an object of the present invention to provide a light-emitting analog meter having high brightness without unevenness in the amount of light of a display pattern such as scales, characters, and hands.

[Means for Solving the Problems] A light emitting analog meter of the present invention made to solve the above problems is a pointer that emits light by back light, a dial whose scale part emits light by back light, and a pointer and a dial. A light diffusing plate disposed on the back surface of the light diffusing plate, a reflector with a concave reflecting surface facing the back surface of the light diffusing plate, and a light source between the light diffusing plate and the reflector at or near the focal position of the reflector. A discharge lamp arranged and a meter internal unit disposed behind the reflector, and a pointer shaft of the meter internal unit is connected to the pointer through the reflector and the light diffusion plate, and The light of the discharge lamp is reflected by the reflector, and the back light passing through the light diffusion plate is applied to the back surface of the pointer and the dial.

[Action]

In the light emitting analog meter of the present invention, the pointer is rotated by a meter internal unit via a pointer shaft that penetrates the reflector and the light diffusion plate. Further, the light of the discharge lamp is reflected by the reflector and diffused by the light diffusing plate, and the diffused light is directly radiated as back light to the pointer and the back surface of the dial so that the pointer and the scale portion emit light. Display light is obtained.

Accordingly, the back surface of the dial and the pointer is illuminated with uniform light with high brightness, and the brightness of the display pattern such as the scale, characters, and pointer is increased.

〔Example〕

FIG. 1 is a partial sectional view of a light emitting type 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, 11 is a meter internal unit that rotates a pointer shaft 11a in accordance with an electric signal input from a circuit (not shown), and its internal structure is the same as that of a conventionally known analog meter. 12 is a case body disposed on the front surface of the meter internal unit 11 on the side of the pointer shaft 11a, 13 is a reflector that is housed in the case body 12 and has a cylindrical concave reflecting surface 13a directed toward the opening side of the case body 12, 14 Is a cold cathode tube (discharge lamp) arranged along the focal point f of the reflector 13.
Reference numeral 14 is connected to an external power source through a lead wire (not shown) drawn from the socket 15 and the case body 12, and constitutes a high output light source. Since the reflector 13 forms a concave mirror by the reflecting surface 13a which is a cylindrical concave surface, the focal point f has a linear shape as shown in FIG.

16 is a light diffusing plate arranged to cover the opening of the case body 12, 17 is a dial arranged in front of the light diffusing plate 16, and 18 is a disc-shaped pointer arranged in front of the dial 17. It is a plate, and the center of the pointer plate 18 is fixed to the tip of the pointer shaft 11a.

As shown in FIG. 2, a black face surface 17a (hatched portion) is formed on the dial 17 by a black printing process on a transparent resin plate, and the scale and numeral portion 17b are left out. The graduations and numerals and the circular portion overlapping the pointer plate 18 are made light transmissive. Further, the pointer plate 18 has a black face surface 18a (hatched portion) formed by a black printing process on a disk-shaped transparent resin plate, and since the black face surface 18a is not partially printed in the radial direction from the vicinity of the center, the pointer plate 18 has a light transmitting property. A slit 18b is formed, and this slit 18b serves as a pointer.

Note that the scale and numeral portions 17b and the slits 18b as described above can also be formed by punching using a light opaque member.

By the way, generally, in a car-mounted analog meter, in many cases, the scale is not formed on the entire circumference, but is generally formed in the range from 8:00 to 4:00 clockwise in the dial of the timepiece.

The scale of the dial 17 of this embodiment is also not formed on the entire circumference as shown in FIG. 2, and the center of the pointer plate 18 is a certain distance d below the center of the height H of the scale portion. It is set in a position that is offset. Further, as shown in FIG. 1, the height of the reflecting surface 13a of the reflector 13 is set so as to include the height H of the scale portion, and the center and the cold cathode tube
The position of 14 coincides with the approximate center P of the height H of the scale portion. And, in correspondence with the center of the pointer plate 18, dial 1
7, the light diffusing plate 16, the reflector 13 and the case body 12 are respectively formed with small diameter shaft holes 17c, 16a, 13b, 12a, and the pointer shaft 11a has the nuclear shaft holes 12a, 13b, 16a, 17c. It passes through and passes under the cold cathode tube 14 and is directed to the center of the pointer plate 18.

With the above configuration, the light from the cold cathode fluorescent lamp 14 is transmitted to the light diffusion plate 16
The light that is diffused by the reflector 13 and is directed toward the reflector 13 is reflected by the reflecting surface 13a into substantially parallel light, and the light diffuser 16
Spread by Then, uniform and bright light is emitted behind the dial 17 and the pointer plate 18 through the light diffusion plate 16, and only the scale, the numbers, and the slit 18b portion are illuminated, and the pointer plate 18 is displayed by the meter internal unit 11. When is rotated, the pointer (slit 18b) that emits light rotates to indicate the scale that emits light, and analog display is performed.

In the light-emitting analog meter of the above embodiment, a slight clearance is provided between the dial 17 and the pointer plate 18, but light leakage may occur from this clearance.
Although this light leakage is almost invisible from the front, the light leakage may be reduced, for example, as shown in FIG.

The light-emitting analog meter shown in the same figure is different from the configuration shown in FIG. 3 in that the dial and the pointer plate are changed, and the dial 17 'is arranged on the front surface. On pointer plate 1
8'is arranged. In FIG. 4, the same components as those in FIG. 3 are designated by the same reference numerals.

There is an opening 17 in the part of the dial 17 'facing the pointer plate 18'.
A c'is formed and a black face surface 17a 'is formed around the c', as in FIG. In addition, the pointer plate 18 '
Like the pointer plate 18, the black face surface 18a 'has a slit 18b' formed therein.

Around the opening 17c 'of the dial 17', as shown in the cross section in FIG. 5, a step portion 17 is formed on the pointer plate 18 'side (light diffusion plate 16 side).
d'is formed, and the periphery of the pointer plate 18 'is loosely fitted in the step portion 17d' to set a certain clearance. Thereby, light leakage from the clearance between the dial 17 'and the pointer plate 18' can be reduced.

〔The invention's effect〕

As described above, according to the present invention, the light diffusing plate, the discharge lamp, the light diffusing plate, and the meter internal unit are arranged in this order on the back surface of the pointer and dial, and the discharge lamp is provided in the vicinity of the focus position of the reflector. Place the indicator shaft of the meter inside machine through the reflector and the light diffusion plate and connect it to the pointer,
The light of the discharge lamp is reflected by the reflector and the back light through the light diffusion plate is applied to the hands and the back of the dial.
Since it is configured as a light emitting analog meter, the light of the discharge lamp is directly radiated as back light by the reflector and the light diffusion plate on the back of the pointer and dial, and the display of scales, letters, pointers, etc. It is possible to obtain a light-emitting analog meter with high brightness without unevenness in the light amount of the pattern.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a light-emitting analog meter according to an embodiment, FIG. 2 is a partial front view of the light-emitting analog meter, FIG. 3 is an exploded perspective view of the light-emitting analog meter, and FIG. FIG. 5 is a view showing another embodiment of the dial and pointer plate of the light emitting analog meter, FIG. 5 is a sectional view of the same embodiment, and FIG. 6 is a view showing an example of a conventional light emitting analog meter. 11 ... Meter internal unit, 11a ... Pointer shaft, 13 ... Reflector, 1
4 ... Cold cathode tube, 16 ... Light diffusion plate, 17,17 '... Dial, 18,1
8 '... pointer plate.

Claims (3)

[Claims] 1. A pointer which emits light by the back light, a dial whose scale part emits light by the back light, a light diffusing plate arranged on the back of the pointer and the dial, and a concave reflecting surface on the back surface of the light diffusing plate. And a discharge lamp arranged between the light diffusion plate and the reflector as a light source at or near the focal position of the reflector, and a meter internal unit disposed behind the reflector. The indicator shaft of the meter internal unit is connected to the pointer by penetrating the reflector and the light diffusing plate, and the light of the discharge lamp is reflected by the reflector so that the back light is transmitted through the light diffusing plate. A light-emitting analog meter characterized by illuminating the back of the dial. 2. The pointer is a disk-shaped pointer plate having a light-transmissive slit formed in the disk-shaped light non-transmissive surface from the vicinity of the center of the disk toward the outer periphery thereof, and the dial has The scale portion is made light-transmissive and has a light-transmissive circular portion that matches the circular shape of the pointer plate on the inner peripheral side of the scale portion, and the pointer plate is aligned and arranged on the front surface of the circular portion. The light emitting analog meter according to claim 1, wherein the pointer shaft is connected to the center of the pointer plate. 3. The pointer is a disk-shaped pointer plate having a light-transmissive slit formed on the disk-shaped light non-transmissive surface from the vicinity of the center of the disk toward the outer periphery thereof, and the dial has The scale portion is made light-transmissive and has a light-transmissive opening portion having a diameter slightly smaller than the pointer plate on the inner peripheral side of the scale portion, and the periphery of the opening portion and the periphery of the pointer plate are provided. 2. The light emitting analog meter according to claim 1, wherein the pointer plates are arranged so as to overlap each other, and the pointer shaft is connected to the center of the pointer plates.