JPH04146829A - Head lamp control device for automobile - Google Patents

Abstract

PURPOSE:To perform a specified time-period passing-signal lighting even in the case of a lighting time delay in a discharge lamp by inputting an operation signal from a passing switch to make a control to cause the discharge lamp to be kept lit, irrespective of the termination of the passing-switch operation, for at least a specified time period after the lighting of the discharge lamp. CONSTITUTION:When a light switch 13 or a passing switch 15 is turned 'ON', an electric current is supplied from a power supply 23 to a discharge lamp circuit 9, whereby each discharge lamp bulb 1, 3 is lit. In a control circuit therefor, a latch circuit 25 serving as a control means is provided in parallel with the passing switch 15 and is also connected to the discharge circuit 9. At this time, the latch circuit 25 latches an ON signal (passing signal) from the passing switch 15 to generate a signal for making an 'ON/OFF' control of a head lamp relay 11. And after confirming, by voltage or current, whether or not the discharge lamp 1 or 3 has been lit via the discharge control circuit 5, the latch circuit 25 keeps the head lamp relay 11 to be in an 'ON' state for only a specified time period set beforehand.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a control device for an automobile headlamp composed of a discharge lamp.

(Prior Art) As a conventional control device for an automobile headlamp constituted by a discharge lamp, there is one shown in FIG. 4, for example.

The two discharge lamps 1.3 used in the headlamp discharge an alternating current voltage from a discharge circuit 7 controlled by a discharge control circuit 5. This discharge circuit 7 and discharge control circuit 5
A headlamp relay 11 is provided in the middle where current is supplied from a DC power source such as a battery to a discharge circuit 9 consisting of
A light switch 13 and a passing switch 15 are provided for turning off the light. The light switch 13 is
At the same time, turn the tail ride relay 19 of the tail lamp 17 to 0.
It is designed to be turned off.

Note that 21 in the figure is a switch that switches the headlamp between a low state and a high state.

In the above control circuit, when the light switch 13 or the passing switch 15 is turned on, current from the power source 23 is supplied to the discharge lamp circuit 9, and the discharge lamp bulb 1.3 is lit.

(Problems to be Solved by the Invention) By the way, one of the characteristics of discharge lamps is an initial lighting delay time. This is the time required to raise the voltage in the discharge circuit 7 to a required voltage in order to generate discharge in the gap of the discharge lamp when lighting the lamp. This delay time is generally about 100 to 150 m5ec after the light switch 13 or the passing switch 15 is turned on and the voltage of the power supply 23 is applied to the discharge circuit 9. Conventional control circuits do not take this lighting delay time into consideration, so when the driver performs passing, the driver must operate the passing switch 15 while taking the delay time into consideration, which is a problem. .

Therefore, this invention was made by focusing on such conventional problems, and provides an automobile headlamp that can easily perform an appropriate passing operation while the light source of the automobile headlamp is composed of a discharge lamp. The purpose is to provide a control device for

[Structure of the Invention] (Means for Solving the Problems) The present invention has been made to achieve the above-mentioned objects. The control means has an illumination lamp, inputs an operation signal from the passing switch, and lights the discharge lamp for at least a predetermined period of time after the discharge lamp is turned on, regardless of whether the operation of the passing switch is completed.

(Function) When an operation signal from the passing switch is input, the control means lights the discharge lamp for at least a predetermined period of time after lighting the discharge lamp, regardless of whether the operation of the passing switch is completed.

(Example) A first example of the present invention is shown in FIG. Note that the same parts as those in FIG. 4 showing the conventional example are given the same numbers, and redundant explanation will be omitted.

In the control circuit shown in this figure, a latch circuit 25 serving as a control means is provided in parallel with the passing switch 15 and connected to the discharge circuit 9. This latch circuit 25 latches (holds) the ON signal (passing signal) from the passing switch 15 and turns the headlamp relay 11 on and off.
Give a signal to control. After that, the discharge control circuit 5
It is checked by voltage or current whether the discharge lamp 1 or 3 is lit via the headlamp relay 11, and after checking, the headlamp relay 11 is kept in the ON state for a preset predetermined time.

The operation of this embodiment will be explained in more detail with reference to FIG. The upper graph represents four types of ON signal times of the passing switch 15. The middle graph shows the lighting time of the discharge lamp 1 or 3 in the conventional control circuit with respect to the ON signal. The lower graph shows the lighting time of discharge lamp 1 or 3 in this example. Assuming that the preset predetermined time is T, (a) If T ON > T + + T p, the lighting time is TON-T.

(b) If TON<TI +TP, the lighting time is TP.

This allows the time T for turning on the driver's passing switch. Even if N is shorter than the discharge lamp lighting delay time T, the lighting time T is always ensured, and a predetermined passing lighting can be performed properly.

Next, a second embodiment of the present invention is shown in FIG. The same parts as in the first embodiment are given the same numbers.

In the above embodiment, the predetermined time TP during which the discharge lamp lights up is fixed, but
In this embodiment, the time TP can be made variable by the latch time adjustment resistor 27. This allows the driver to change the length of T as desired or necessary.

[Effects of the Invention] As described above, according to the present invention, a predetermined passing lighting can be performed even if the discharge lamp has a lighting delay time. Therefore, the passenger can perform a passing operation without considering the lighting delay time of the discharge lamp, making the operation extremely easy.

[Brief explanation of drawings]

FIG. 1 is a circuit according to a first embodiment of the present invention, FIG. 2 is a circuit showing a second embodiment, FIG. 3 is a graph diagram explaining the operation in the first and second embodiments, and FIG. This is a conventional circuit. 1.3...Discharge lamp 5...Discharge control circuit 7...Discharge circuit 9...Discharge lamp circuit 11...Headlamp relay 1
3... Light switch 15... Passing switch 23... Power supply 25... Latch circuit (control means) agent Patent attorney Hidekazu Miyoshi

Claims (1)

[Claims] The light source is a discharge lamp, and has an automobile headlamp that can be turned on by operating a passing switch, and an operation signal from the passing switch is input to pass the discharge lamp for at least a predetermined period of time after the discharge lamp is turned on. 1. A control device for a headlamp for an automobile, comprising a control means for turning on the headlamp regardless of whether a switch operation is completed.