JPH0555334B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a headlamp for an automobile, and more particularly to a headlamp using a discharge lamp as a light source.

[Conventional technology]

Conventionally, discharge lamps take 15 to 60 seconds to start up, and if they unexpectedly turn off while driving due to a power outage or other reason, it takes the same amount of time to restart them, and during this time you lose visibility and are at risk for safety. Since this would cause problems, it was never used as a light source for automobile headlights.

[Problem to be solved by the invention]

However, the above-mentioned discharge lamps have excellent brightness and color rendering, and for example, in the current state of automobile transportation, which has become faster due to the development of road networks in recent years,
Conventional headlights using incandescent lamps have reached their limits in terms of brightness and color rendering, resulting in the problem of insufficient visibility, and the use of discharge lamps as a light source has become an issue in order to further improve safety. ing.

[Means to solve the problem]

As specific means for solving the above-mentioned problems, the present invention provides a first lighting device that uses a discharge lamp as a light source and has a passing beam light distribution, and a double filament incandescent lamp as a light source that has a passing beam light distribution and a running beam light distribution. a lighting detection unit that detects lighting of the discharge lamp; and a lighting detection unit that detects lighting of the discharge lamp; and a lighting detection unit that detects lighting of the discharge lamp; and a lighting detection unit that detects lighting of the discharge lamp; and a control unit that turns on/off the filament according to a predetermined procedure, and when the lighting of the low beam is being instructed and the lighting of the discharge lamp is not detected by the lighting detection unit, the control unit controls the lighting of the discharge lamp. By providing a discharge lamp headlamp characterized by lighting the filament on the side of the second lamp that corresponds to the passing beam of the incandescent lamp, problems such as startup delay when using a discharge lamp as a light source can be solved. It also provides compensation and solves the conventional problems mentioned above.
Furthermore, a color filter is disposed in either the first lamp or the second lamp to match the emitted light color with respect to the other lamp, and the discharge lamp and the incandescent lamp are arranged. This further improves practicality by eliminating discomfort when switching between the two.

【Example】

Next, the present invention will be explained in detail based on an embodiment shown in the drawings. What is shown in FIG. 1 is a circuit diagram of the lighting method of the present invention, and what is indicated by the reference numeral 1 in the figure is a first lamp, and this first lamp 1 is designed exclusively for low beam light distribution. Further, the light source is, for example, a discharge lamp 1a such as xenon. In the present invention, a second lamp 2 is further provided to be installed side by side with the first lamp 1, and this second lamp 2 is a double filament incandescent lamp, for example, an H-4 halogen lamp 2a, which emits a passing beam. The light distribution and the traveling beam light distribution are configured to be switchable. The discharge lamp 1a of the first lamp 1 is provided with a lighting detection section 3 that detects that the discharge lamp 1a is lit by detecting a discharge current, etc., and the output of the lighting detection section 3 is sent to a control section 4. It has been entered. In addition to the output from the lighting detection section 3 described above, the control section 4 receives, for example, an output from a changeover switch Sw having contacts s and m corresponding to a passing beam and a running beam operated by the driver. The output of this control unit 4 is connected to a lighting circuit 5 comprising, for example, an inverter of the discharge lamp 1a, and is also connected to the passing beam filament 2aa of the H-4 halogen lamp 2a of the second lamp 2.
and the traveling beam filament 2ab. It goes without saying that the discharge lamp 1a is usually equipped with a step-up transformer T, a ballast B, etc. necessary for lighting this type of discharge lamp. Next, to explain the lighting method of the present invention configured as above, the control section 4 determines which side the changeover switch Sw is turned on,
When the contact s on the low beam side is turned on, the lighting circuit 5 is activated, and at the same time, current is also supplied to the low beam filament 2aa of the H-4 halogen lamp 2a, and this low beam filament 2aa is lit. let Therefore, although the discharge lamp 1a is not lit, the passing beam filament 2 of the second lamp 2
Due to the luminous flux from aa, visibility is secured as soon as the changeover switch Sw is turned on, as shown by the passing beam incandescent lamp lighting curve 2AA in FIG. Subsequently, although there are differences due to differences in environmental temperature conditions such as summer and winter, the discharge lamp 1a turns on after a predetermined time, and this lighting is detected by the lighting detection section 3, and its output is The information is transmitted to the control unit 4, but as shown by the passing beam discharge lamp lighting curve 1A in FIG. Therefore, as a waiting time until the brightness rises to about 70%, the control unit 4 performs a predetermined procedure such as, for example, using a timer to measure the elapse of a certain period of time after the lighting is detected. Afterwards, the filament 2aa for the low beam is turned off, or the low beam of the incandescent lamp is gradually dimmed and turned off so that the road illumination becomes uniform. As a result, the road illumination is switched from the lighting shown by the low beam incandescent lamp lighting curve 2AA in FIG. 2 to the low beam discharge lamp lighting curve 1A, that is, from the second lamp 2 to the first lamp 1. . The control unit 4 is also provided for unexpected turning off of the discharge lamp 1a, and the control unit 4 detects the lighting while the switch Sw commands the control unit 4 to turn on the setting point s. When the lighting detection from the section 3 is stopped, the control section 4 determines that the discharge lamp 1a is unexpectedly turned off, and immediately turns on the passing beam filament 2aa to prevent loss of visibility, so that the discharge lamp 1a is turned off unexpectedly. At the time of relighting, the switching from the low beam filament 2aa to the discharge lamp 1a is performed using the same procedure as described above. Further, when the changeover switch Sw is switched to the contact m on the running beam side, the control unit 4 turns off the discharge lamp 1a and turns on the running beam filament 2ab,
In this case, the traveling beam filament 2
Since ab is an incandescent lamp, as shown in Figure 2, it can be instantly switched from the passing beam discharge lamp lighting curve 1A to the driving beam incandescent lamp lighting curve 2AB, or the discharge lamp is turned off even when the driving beam is on. do not. In addition, the light distribution characteristics of modern automobile headlights are basically set so that the low beam side is used for normal driving, so if only the low beam side is used as a discharge lamp as in this example, , sufficient practical effects can be obtained. What is shown in FIG. 3 is another embodiment of the present invention, and during the course of many experiments to realize this invention, it was found that one side of a four-lamp headlamp, etc., is basically a one-piece lamp, e.g. When switching from the discharge lamp 1a to the running beam filament 2ab, it was found that the difference in color temperature between the two light sources caused a considerable sense of discomfort, and this was taken as a countermeasure. As a means for achieving the above purpose, for example, the first lamp 1, that is, the discharge lamp 1a is used as a light source,
A color filter 6 that lowers the color temperature, such as amber, is disposed on the lamp with a higher color temperature, and the color filter 6 acts to reduce the color temperature of the second lamp 2.
The purpose is to match the color temperature with the color temperature, and eliminate the sense of discomfort when switching as described above. In this embodiment, the color filter 6 is arranged as a plate on the entire back surface of the lens 1b of the first lamp 1.
It is possible to make changes such as attaching a cap to the lens 1b or forming the lens 1b itself in amber color.
You are free to adopt any means for changing the light color. Further, although not shown, the first lamp 1 is left as is, and a color filter for raising the color temperature, such as blue, is provided on the second lamp 2 side to match the color temperature of both lamps 1 and 2. Naturally, other methods are possible, and which one to choose should be carried out in consideration of the interests of both parties.

【Effect of the invention】

As explained above, according to the present invention, there is a first lamp which uses a discharge lamp as a light source and has a passing beam light distribution, and a second lamp which is an incandescent light source and has a passing beam light distribution that is substantially the same as the first lamp. A lamp is prepared, and the second lamp is turned on when the discharge lamp is started or unexpectedly turned off, and the lighting detection unit and the control unit switch the lamp when the discharge lamp reaches a sufficient brightness. By using an incandescent lamp to compensate for the start-up or unexpected turn-off of a discharge lamp, a headlight that uses this type of discharge lamp as a light source can be achieved by quickly turning on the lamp and eliminating loss of visibility, improving visibility. This makes it possible to achieve excellent results in improving the safety of automobile traffic. Furthermore, in this type of headlamp in which different light sources are combined, by matching the emitted light colors of both lamps, the sense of discomfort that occurs when switching is eliminated, and the practicality of this type of combined lamp is further enhanced.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram showing one embodiment of a discharge lamp headlamp according to the present invention, FIG. 2 is a graph showing the same procedure, and FIG. 3 is a schematic circuit diagram showing another embodiment of the discharge lamp headlamp according to the present invention. FIG. 3 is a cross-sectional view showing important parts. 1...First lamp, 1a...Discharge lamp, 2...Second lamp, 2a...H-4 halogen light bulb, 2aa
...Filament for passing beam, 2ab...
Filament for traveling beam, 3... lighting detection unit,
4... Control unit, 5... Lighting circuit, 6... Color filter, 1A... Passing beam discharge lamp lighting curve, 2AA... Passing beam incandescent lamp lighting curve,
2AB...Traveling beam incandescent lamp lighting curve, Sw...
Changeover switch.

Claims (1)

[Scope of Claims] 1. A first lamp that uses a discharge lamp as a light source and has a passing beam light distribution, and a second lamp that uses a double filament incandescent lamp as a light source and can switch between a passing beam light distribution and a running beam light distribution. A lighting device, a lighting detection unit that detects lighting of the discharge lamp, and a signal from the lighting detection unit to turn on/off the filament of the second lighting device on the side corresponding to the passing beam of the incandescent lamp according to a predetermined procedure. During the period when the low beam is instructed to turn on,
The discharge lamp headlamp is characterized in that when the lighting detection unit does not detect lighting of the discharge lamp, the control unit lights a filament of the second lamp on the side corresponding to the passing beam of the incandescent lamp. . 2. A color filter is disposed on either the first lamp or the second lamp to match the color of the emitted light with respect to the other lamp. Discharge lamp headlights described in scope 1.