JP3788825B2 - Pointer illumination device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pointer illuminating device attached to a meter such as a vehicle, an aircraft, or a ship, and in particular, guides a light beam on the average within a pointer direction of the meter within the rotation instruction range, thereby providing uniform and non-uniform illumination. The present invention relates to a self-luminous pointer illumination device to be performed.
[0002]
[Prior art]
Conventionally, in vehicles, airplanes, ships, etc., many instruments that display measured values such as speed, engine speed, mileage, remaining fuel amount, etc. are installed, but many of these are analog type instruments. Some of them are provided with a self-luminous pointer illumination device.
[0003]
4A and 4B show a conventional self-luminous pointer illumination device, in which FIG. 4A is a cross-sectional explanatory view of a main part thereof, and FIG. 4B is a plan view of a reflection surface thereof. FIG. 5 is a plan view showing the shape of a light guide plate of another conventional self-luminous pointer illumination device.
[0004]
A conventional self-luminous pointer illumination device will be described with reference to FIGS.
[0005]
In FIG. 4, 5 is a dial plate on which a scale, characters, etc. are printed on the surface of a translucent substrate. On the dial plate 5, a pointer 3 made of a transparent material is attached to the dial plate 5 at the tip of the pointer shaft 2 erected from the internal unit (not shown) through the through hole 6 in the middle of the dial plate 5. It is attached substantially in parallel. The base 3a of the pointer 3 is formed with a reflecting surface 3c that reflects the light received from the light receiving surface 3b toward the tip of the pointer.
[0006]
The through-hole 6 formed in the dial plate 5 extends from a side parallel to a side perpendicular to the optical axis connecting the two light sources (not shown) disposed at the ends of the dial plate and the pointer shaft 2. A first hole having an inclination angle of preferably 45 degrees from the front surface to the back surface of the dial plate 5 on the light incident side from the light source as an inner peripheral wall continuous with the side perpendicular to the optical axis. Reflective surfaces 5a and 5b are formed, respectively, and an inclination angle of 45 degrees is similarly formed in the same direction as the first reflective surfaces 5a and 5b from the upper center of both side walls of the penetrating light 6 to the back surface of the dial plate 5. The second reflecting surfaces 5c and 5d are formed.
[0007]
According to the configuration of the conventional example of FIG. 4, the light rays in the direction of the light beam connected to the pointer shaft 2 among the light beams separately introduced from the two light sources into the dial plate 5 are the first reflecting surfaces 5a and 5b. Because the light beam reflected by the light beam enters the pointer 3 and the light beam measured by the through-hole 6 is reflected by the second reflecting surfaces 5c and 5d and enters the pointer 3, the periphery of the through-hole 6 The light beam incident on the dial 5 can be used as illumination light for the pointer 3 with very little loss in the thickness direction of the dial plate 5 and the projection width of the pointer base portion 3a.
[0008]
In FIG. 5, reference numeral 14 denotes a light guide plate. The light guide plate 14 is disposed behind a dial (not shown). At the end of the light guide plate 14 positioned below the pointer base 13a, a step-like planar reflection along the rotation trajectory of the pointer base light-receiving surface 13b divided into a plurality of portions inclined in the same direction toward the light source 18 side. Surfaces 14a, 14b, 14c, and 14d are provided.
[0009]
According to the configuration of the conventional example shown in FIG. 4, the illumination light from the light source 18 is guided through the light guide plate 14, and is received by the pointer 3 by the reflecting surfaces 14a, 14b, 14c, and 14d formed in a step shape. Since the light is reflected on the rotation orbit area of the surface 13b, the pointer 13 always receives an average amount of light regardless of the position of the pointer, and uniform illumination with almost no unevenness is made within the rotation instruction range.
[0010]
[Problems to be solved by the invention]
In the conventional self-luminous pointer illumination device shown in FIG. 4, the pointer can emit light uniformly, but there is a problem that two light sources are required, and the conventional self-illuminating device shown in FIG. Even in the light emitting type pointer illumination device, the pointer can emit light uniformly, but even if it is effective for a gauge or the like having a narrow deflection angle, it can be used for a speedometer of an automobile, an operation recorder, etc. There was a problem that it could not be used for a wide deflection angle.
[0011]
The present invention aims to solve this problem.
That is, an object of the present invention is to provide a self-luminous pointer illumination device that uniformly emits an instrument pointer having a wide deflection angle with a single light source.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a dial plate, a pointer made of a transparent material provided substantially parallel to the dial plate, and a light guide plate that guides illumination light from one light source to the light receiving surface of the pointer. In order to make it possible to evenly emit a meter pointer with a wide deflection angle even with a single light source, the end of the light guide plate arranged along the rotation trajectory of the light receiving surface of the pointer Inclined to reflect light from the light source in the direction of the light receiving surface, arranged along the optical axis direction, and so as to approach the light receiving surface as the distance from the light source increases in the thickness direction of the light guide plate A plurality of planar reflection surfaces divided into a plurality of positions are provided in a sawtooth shape in the thickness direction of the light guide plate, and the plurality of planar reflection surfaces straddle the front and rear of the through hole at the end of the light guide plate and the through hole. together provided Te, the plurality of planar anti Among the surfaces, it is characterized in that the area of the planar reflecting surface which is closest sequences to the light source is formed to a minimum.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a cross-sectional view of a pointer illumination device showing an embodiment of the present invention, FIG. 2 is a plan view showing the shape of a light guide plate, and FIG. 3 is a line AA in FIG. It is sectional explanatory drawing (shaft hole part not shown).
[0015]
The pointer illuminating device of the present invention is arranged on the dial 25 formed of a transparent material, the pointer 23 formed of a transparent material attached substantially parallel to the dial 25, and the back of the character plate 25. And a light guide plate 24.
[0016]
At the end portion of the light guide plate 24 arranged along the rotation path of the light receiving surface 23b of the pointer 23, the planar reflecting surfaces 24-1a and 24-1b divided into three inclined toward the light source 28 in the same direction. And 24-1c are provided in a sawtooth cross section in the thickness direction of the light guide plate 24 across the through hole 26 at the end of the light guide plate 24 and across the through hole 26.
More specifically, as shown in FIGS. 2 and 3, the light receiving surface 23b of the pointer is rotated so that a single light source 28 can uniformly emit a light pointer with a wide deflection angle. At the end of the light guide plate 24 arranged along the orbit, the light from the light source is inclined so as to reflect in the light receiving surface direction and arranged along the optical axis direction, and the thickness direction of the light guide plate The planar reflecting surfaces 24-1a, 24-1b, and 24-1c divided into three parts whose height positions are changed so as to approach the light receiving surface as the distance from the light source is provided in a sawtooth shape in the thickness direction of the light guide plate. The planar reflective surface is provided across the through hole 26 at the end of the light guide plate and across the through hole, and the planar reflective surface 24-1a arranged closest to the light source among the planar reflective surfaces. The area is formed to the minimum
[0017]
Above the planar reflecting surfaces 24-1a, 24-1b and 24-1c, the irradiated light reflected by the planar reflecting surface is approached by the pointer base 23a and approaches the rotation trajectory of the light receiving surface 23b of the pointer 24. The irradiation part 24-2 for guiding the light beam is formed so as to protrude from the dial plate 25. However, any light beam may be used as long as it can guide the irradiation light reflected from the planar reflection surface to the rotation orbit of the light receiving surface 23b. . For example, when the light guide plate 24 and the light receiving surface 23b of the pointer 23 are sufficiently close to each other or the portion is a transparent dial plate, the irradiation unit 24-2 does not have to protrude from the dial plate 25. .
[0018]
The length, width, and number of the planar reflecting surface 24-1 are appropriately set according to the thickness of the light guide plate 24, the radius of rotation of the light receiving surface 23 b, the indication range of the pointer 23, and the like. The inclination angle of the plane reflecting surface 24-1 is preferably formed so as to have 45 degrees in the light beam direction, but is not limited thereto.
[0019]
The pointer illumination device formed as described above is incorporated into an instrument frame to provide an automobile instrument.
[0020]
According to the above-described configuration of the present invention, the light emitted from one light source, that is, the light source 24 is guided through the light guide plate 24, and each reflective surface is provided in a sawtooth shape in the thickness direction of the light guide plate 24. Since the light is reflected by 24-1a, 24-1b, and 24-1c and is reflected from the irradiation unit 24-2 to the rotation orbit region of the light receiving surface 23b of the pointer 23, the pointer 23 having a wide deflection angle is related to the indicated position. There is always an average amount of light incident, and uniform illumination with almost no unevenness is made in the rotation instruction range.
[0021]
【The invention's effect】
A single light source with a wide swing angle, for example, a self-luminous pointer illumination device that can uniformly emit instrument pointers such as automobile speedometers and operation recorders, can reduce the cost of the instrument. In addition, the weight of the instrument can be reduced and the space of the instrument can be used effectively.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a pointer illumination device showing an embodiment of the present invention.
FIG. 2 is a plan view showing a shape of a light guide plate.
FIG. 3 is a cross-sectional explanatory view taken along the line AA in FIG.
FIGS. 4A and 4B show a conventional self-luminous pointer illumination device, in which FIG. 4A is a cross-sectional explanatory view of a main part thereof, and FIG. 4B is a plan view of a reflection surface thereof.
FIG. 5 is a plan view showing the shape of a light guide plate of another conventional self-luminous pointer illumination device.
[Explanation of symbols]
23 Pointer 23b Pointer light-receiving surface 24 Light guide plates 24-1a, 24-1b, 24-1c Reflective surface 24-2 Irradiation unit 25 Dial plate 26 Through hole 28 Light source

Claims (1)

In a pointer illumination device including a dial, a pointer made of a transparent material attached substantially parallel to the dial, and a light guide plate that guides illumination light from one light source to a light receiving surface of the pointer,
The light from the light source is received at the end of the light guide plate arranged along the rotation trajectory of the light receiving surface of the pointer so that a single light source can uniformly emit an instrument pointer having a wide deflection angle. Inclined to reflect in the surface direction and arranged along the optical axis direction, and divided into a plurality of parts whose height positions were changed so as to approach the light receiving surface as they moved away from the light source in the thickness direction of the light guide plate It provided a planar reflective surface in the thickness direction of the light guide plate cross serrated, with provided across the front and rear as well as the through hole of the through hole of the end portion of the plurality of planar reflecting surfaces the light guide plate, said plurality The pointer illumination device characterized in that the area of the planar reflecting surface arranged closest to the light source among the planar reflecting surfaces is formed to a minimum .

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