JPS5839400A - Signal lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a signal lamp device.

In general, a traffic light device, for example, a road traffic signal light device, mainly consists of a reflector, 1° lens, 2. and a light bulb 3. Note that FIG. 5A is a cross-sectional view, and FIG. 2B is a front view. The reflector 1 is generally a parabolic mirror of revolution with a focal point F, and in order to obtain high reflectance and specularity, this surface is made of electrolytically polished or chemically polished high-purity aluminum, or made of metal or It is constructed by performing treatments such as aluminum vapor deposition on resin. on the other hand.

Lens 2 is made of glass or resin.

It has the function of controlling the direct light from the light bulb 3 and the reflected light from the reflecting mirror 1 in a predetermined direction, as well as the function of a five-color filter and dust prevention. 1. As the light bulb 3, a general type light bulb or a band mirror type light bulb whose inside surface is usually painted white is used. The light bulb 3 is fixed so that its emission center is near the focal point F of the reflecting mirror 1.

When a car driver or pedestrian sees a traffic light,
In addition to proper light distribution (luminous intensity distribution) and chromaticity, the light emitting surface (
The lack of unevenness in brightness (unevenness in brightness) on the lens surface is particularly important. Floodlights are similar lighting equipment to signal lights, but they differ from signal lights in that uneven brightness on the light emitting surface is not a problem with floodlights.

To reduce uneven brightness on the light emitting surface of signal lights.

As the light bulb 3, use a light bulb whose inner surface of the bulb is painted white (white painted light bulb), and also provide small protrusions (stippling) 1f: on the inner surface of the lens, or make fine cuts 4 as shown in Fig. 1 (b). However, the more diffusive the light bulb or lens becomes, the more difficult it becomes to control the light. ) becomes difficult to obtain.

When a transparent type 9 bulb, which is a transparent bulb, is attached to a conventional signal lamp, it will look like the one shown in Figure 2.

(The light 5 emitted from the filament becomes light 6 parallel to the optical axes z and z', so the central luminous intensity increases significantly. However, if you look at this signal light from a diagonal direction slightly off the optical axis, , as shown in Fig. 3(a), only part 7 of the lens surface appears to be shining brightly.Also, if the light bulb is installed a little off from the predetermined position, even from the front of the signal light, the part 7 of the lens surface appears bright. As shown in (middle), a ring-shaped bright and dark pattern 8 appears. For this reason, transparent light bulbs cannot be used in conventional signal lights.

As shown in FIG. 4, the signal lamp device 9 is installed so that the optical axes Z and Zl are substantially horizontal. Therefore, the radiation angle range required for signal lights is the horizontal axis. , o' (range A in FIG. 4) and above (range B) is completely unnecessary.

However, in conventional signal lights, the emitted light is emitted above the horizontal axes o and o', and even the light emitted below is within the angle range required for a signal light (horizontal angle: 40° left and right). 45°) and the light utilization rate is very low. Therefore, in order to obtain the characteristics required for signal lights, large wattage bulbs must be used.

The present invention provides a signal lamp device that reduces uneven brightness on a light emitting surface, reduces unnecessary light emitted upward from the optical axis as a signal lamp, and increases light utilization.

An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 6, two reflecting mirrors 1o are arranged on the main reflecting mirror 11 surface (rotational quadratic curved surface) which has a large curvature and is almost flat, and which has a vertically asymmetrical shape and has a smaller curvature than the main reflecting mirror 11 surface. The local reflecting mirror 12f has a convex lower portion or a concave upper portion and is distributed over the entire main reflecting mirror 11. Fig. 5 shows the reflecting mirror structure and the light reflection path when the main reflecting mirror 11 is a parabolic mirror of revolution and the local reflecting mirror 12 is a substantially hemispherical mirror. The front lens is shown with it removed.

Light bulb (transparent light bulb) so that the light emitting center (filament center) of the light bulb 13 is at the focal point F of the main reflecting mirror 11 of this reflecting mirror.
Install. Main reflector 1 from filament (not shown)
After the light 14 incident on one surface is reflected by the main reflecting mirror 11, it becomes light 15 substantially parallel to the optical axes Z and Zl, increasing the central luminous intensity. on the other hand.

The light beams 16 and 17 incident on the local reflecting mirror 12 become downward light beams 18 and 19 slightly away from the optical axes z and zp, respectively, and the total luminous intensity in the downward direction from the horizontal is increased.

FIG. 6 is for explaining these in more detail.

This is an enlarged view of a part of the reflecting mirror. Main reflector 1
Light 14 incident on 1 is emitted in a direction 15 parallel to the optical axis. On the other hand, among the light incident on the surface of the local reflector 12, the light 2° incident on the center of the five local reflectors 12 is emitted in a direction 21 substantially parallel to the optical axis, but the light 22 incident on other parts ~24
are respectively spread downward to 26 and 27 and released.

FIG. 7 shows the radiation angle range of the signal light, and Z' represents the optical axis. The angle range required for the signal light is Pl, P2
．． P3. It is in the range of P4. Figure 5 (a), (b)
In the reflecting mirror having the structure shown in FIG. As a result of being emitted in the direction D) in the figure, the light emitted in unnecessary directions as a signal light is reduced, and the efficiency of the signal light device can be improved.

When looking from the front of the reflecting mirror 10i having such a structure.

A portion (center part) of the main reflecting mirror 11 surface and the local reflecting mirror 12 surface appears to be shining. Also, the optical axis Z.

When viewed from an oblique direction away from Z', the main reflecting mirror 11 surface is dark, but any part of the five local reflecting mirrors 12 is illuminated, so that the entire reflecting mirror appears spotty.

However, by appropriately selecting the size and number of local reflectors, the lens surface can be seen to shine uniformly at the actual viewing distance.

Figures 8(a) and 8(b) show examples of the horizontal cross-sectional light distribution characteristics and vertical cross-sectional light distribution characteristics of this signal light, respectively, where curves I and I' are the orientation curve II due to the main reflector.
, II' is the light distribution curve 1 by the local reflector m, m
' is the composite light distribution. The vertical cross-section light distribution of the signal light has a high center luminous intensity, and the luminous intensity in the direction below the optical axis increases significantly, so it has favorable light distribution characteristics as a signal light.

As the ratio of the area of the local reflective mirror surface to the entire reflective mirror surface increases, the scattered component increases and the central luminous intensity relatively decreases. Furthermore, as the curvature of the 5 local reflectors is made smaller, the angular range in which the 1 local reflector shines becomes wider, but the light distribution n and u' by the local reflectors in Figure 8 become flat, and therefore the central luminous intensity decreases. do.

In addition to the hemispherical shape shown in Fig. 5(a), Φ), the shape of the local reflector may be polyhedral, triangular, or semi-elliptic, and the same effect can be obtained with either a convex or concave surface. can get. The light distribution characteristics of the signal lamp and the brightness characteristics of the lens surface vary greatly depending on the size and number of local reflecting mirrors (that is, the ratio of the area that one local reflecting surface occupies to the entire reflecting mirror surface), and their shape. When the size of the local reflector is constant.

As the number of local reflectors is small, the luminous intensity at the center is high, but because the distance between the local reflectors becomes wider, it appears mottled on the lens surface as shown in Figure 9, and for this reason, especially at short distances. −〇My discomfort has increased.

It may become difficult to see. This is because our eyes have particularly good visual acuity in the center (approximately 2 degrees angle) and are able to distinguish even very small objects individually. Light distribution characteristics of signal lights using conventional reflectors and lenses.

As a result of investigating the brightness characteristics of the lens surface and conducting an experiment to evaluate the appearance, the ratio of the area occupied by the two local reflecting mirrors to the total mirror surface of the reflecting mirror is 10% to 60%.9 The mutual spacing between the local reflecting mirrors (
When Ll or L2)'e in Fig. 6 is set to less than % of the lens diameter, the specified light distribution characteristics can be obtained even when using a transparent light bulb, and the discomfort caused by the appearance of a single spot of light is eliminated.
It was confirmed that the brightness unevenness on the lens surface could be reduced to a level that does not pose a practical problem.

As explained above, the present invention has a main reflecting mirror with a structure in which a large number of local reflecting mirrors whose shapes are vertically asymmetric are scattered, so that one reflecting mirror itself has scattering and reflection characteristics with appropriate directionality. Therefore, even if you use a transparent light bulb or a light bulb as thin as the paint film, or reduce the diffusivity of the lens, you can still obtain the desired light distribution performance as a signal light, and the uneven brightness on the lens surface can be greatly reduced. . In addition, by reducing the diffusivity of the lens and using a transparent bulb, light can be controlled efficiently, making it possible to emit more light in the required direction as a signal light. Therefore, the same effect as a signal light with a conventional structure using a white-painted light bulb for the reflector can be obtained with a lower wattage light bulb, making it possible to significantly reduce the power consumption of the signal light. In addition to regular light bulbs, you can also use band mirror light bulbs to achieve the same effect.

[Brief explanation of the drawing]

Figures 1 (a) and (1)) show the structure and light path of a conventional signal lamp, and its front view, respectively. Figure 2 shows the reflection of light when a transparent light bulb is used in a conventional signal lamp. An explanatory diagram showing the route, Figure 3 shows the state of the shine on the lens surface of the signal light device shown in Figure 2, where (a) is viewed from an oblique direction, and (in the figure) is viewed from the front. It is a diagram. Fourth
The figure is an explanatory diagram showing the installation situation of a signal lamp and the radiation angle range necessary for a signal lamp.O Figure 5 is for explaining a signal lamp according to an embodiment of the present invention, and (a) is the main figure. Figure 6 shows a reflective structure in which a large number of local reflectors with an asymmetric external shape are scattered on the reflector and the light reflection path. Fig. 7 is a partially enlarged illustration of the reflector shown in the figure, and Fig. 1 shows the radiation angle range of the signal light.
Figures (a) and Φ) are horizontal cross-sectional and vertical light distribution characteristics diagrams of the signal lamp shown in Figure 6, respectively, and Figure 9 is the lens surface of the signal lamp shown in Figure 6 when the number of 5 local reflectors is small. FIG. 10...Reflector, 11...Main reflective surface, 12
″...Local reflective surface, 13...Light bulb. Name of agent: Patent attorney Toshio Nakao and 1 other person Ward @2 Figure 43

Claims (3)

[Claims] (1) Reflector, a lens provided in front of this reflector. and a light bulb disposed between the reflecting mirror and the lens, the reflecting mirror being vertically asymmetrical over the entire main reflecting mirror consisting of a rotating mirror having a smooth surface,
A signal lamp characterized by dispersing local reflecting mirrors each having a convex lower portion or a concave upper portion. (2) The area of the local reflector is 10 to 50 times the area of the reflector.
% of the signal lamp according to claim 1. (3) The signal lamp device according to claim 1, wherein the distance between the local reflecting mirrors is set to be less than % of the diameter of the lens.