JPS62157840A - Reserve lighting system for headlamp - Google Patents

Abstract

PURPOSE:To properly secure lighting state in the breaking of wire by lighting a high beam filament and reducing transmission factor of a duplex GH type liquid crystal element provided on the front surface of a headlamp when a low beam filament in the headlamp is broken. CONSTITUTION:A duplex GH type liquid crystal element 15 controlled in its transmission factor by a control means 22 is provided on the front surface of the lens 13 of a headlamp 11 providing a low beam filament 14a and a high beam filament 14b built in a bulb 14. And, a break detecting sensor 20 detects the break of said filaments 14a, 14b, and when the break of one filament is detected by said sensor 20, a tandem dimmer switch 23 is controlled by a switching circuit 21, so that the electric current is supplied to the other filament side. Also, at this time, when the low beam filament 14a is broken, control means 22 is operated to reduce transmission factor of said liquid crystal element 15, so that the illumination of the headlamp 11 is weakened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a headlamp that is attached to a vehicle such as an automobile and has a low beam filament and a high beam filament. This relates to a so-called reserve lighting system that lights up the other filament immediately.

[Prior art]

Generally, as this type of reserve lighting 5A neck, one having the configuration shown in FIGS. 4 and 5 is known.

In this configuration, 1 is a DC power supply, and 2 is a lighting switch. When the lighting switch 2 is turned on, either the low beam filament 3a or the high beam filament 3b of the headlamp 3 is turned on. A current detection section 4 and a dimmer switch 5 are provided between the lighting switch 2 and the headlamp 3, and the current detection section 4 has a relay coil 4a and a relay contact 4.
b, and the signal from relay contact 4b is f9iP
Used as an il detection signal. This disconnection detection signal is used to supply current to the filament on the non-broken side by a switching circuit 7 via a switching circuit 6 such as a transistor or a Nyristor to cope with the disconnection.

In this case, as a dimming circuit system, an oscillation circuit 8 is provided,
The effective value voltage control method using a chopper or the circuit configuration in which one switch circuit 7 is used is shown in 1 and ■ in Figure 5.
: This is based on a voltage drop method using a series resistor R. Note that 5a is an interlocking dimmer switch.

According to such a conventional structure, the dimming means during reserve only fixedly lowers the terminal voltage of the lamp, and there is also the problem that cutting noise is generated by the transmitting circuit and has an adverse effect on the outside. Not only that, but also there was a problem of heat generation in the case of a voltage drop due to a series resistor, and the series resistor had to be attached externally, creating a problem in unitization.

[Problem that the invention seeks to solve]

The present invention attempts to solve the problems of chopping noise, heat generation due to series resistance, heat generation due to series resistance, and the problem of fixing the degree of attenuation, which are conventional problems. be.

[Means to solve the problem]

As specific means for solving the above problems, the present invention provides a headlamp that is equipped with a two-layer G H type liquid crystal rod on the front surface of the lens and has a low beam and a high beam filament, and a means for detecting a break in both of the filaments. , a switching control circuit for controlling the reserve, a means for detecting the usage state of the filament, and a means for turning on the high beam filament via the switching circuit when the low beam filament is broken, and at the same time controlling the double layer G.
The present invention provides a reserve lighting system for a headlamp, characterized in that it is equipped with a control means for controlling the transmittance of the H-type liquid crystal element to reduce the transmittance of the H-type liquid crystal element. Variable control is performed by applying an AC signal,
Since there is a device that can reduce light by changing the transmittance of light, the degree of light attenuation can be varied, and the problems of noise and heat generation can be solved.

(Embodiment) Next, the present invention will be described in more detail with reference to the illustrated embodiment. Reference numeral 11 is a headlamp, a lens 13 is attached to the front of the headlamp beam flap 12, and a bulb 14 is attached inside. It is being

This bulb 14 includes a low beam filament 14a and a high beam filament 14b.

A two-layer GH type liquid crystal element 15 is disposed in front of the lens 13 of the headlamp 11. As shown in FIG. 2, this two-layer G1'' type liquid crystal probe 15 has three glass plates 16 disposed, electrodes 17 are attached to each of these glass plates, and G)l is provided between each glass plate. A liquid crystal cell is constructed by enclosing liquid crystal 18. And liquid crystal element 15
The electrode 17 serves as a control means for controlling the light transmittance of the electrode 17.
An alternating current signal transmitter 19 is connected to provide an alternating current signal.

The reserve lighting system configured in this way is
It is shown schematically in FIG. In the same figure, 20 indicates 1100 headlamps or 1 high beam filament.
The sensor that detects fJi8, 21 is the amount detection pinzer 2
22 is a switching circuit for controlling the reserve for supplying current to the unbroken filament side in response to a signal from m+.
It is a means of control.

The disconnection detection sensor 20 is connected to the headlamp 11 via a pair of demer switches 23 as switching means for the high beam and low beam of the headlamp, and the contact terminals of the two demer switches 23 are connected to There are side lights that cross each other with the power supply circuit. In other words, one contact terminal is low beam filament 1.
When connected to the 4a side, the other connection terminal is connected to the high beam filament side. Furthermore, the Demer Switch 2
A detection circuit 24 is disposed between the headlamp 11 side circuit 3 and the switching circuit 21 as a means for detecting the usage state of the filament, that is, the operating state of the low beam filament +-148 or the high beam filament 14b. It is set up.

In this way, in the 1f-brighting system, when the low beam filament 14a is disconnected with the demer switch 23 set to the low beam side as shown in the figure, the detection sensor 20 detects this and sends the signal to the switching circuit 21. When the voltage is applied to the high beam filament 14b, the switching circuit 21 immediately switches on the high beam filament 14b.
At the same time, the AC signal generator 19, that is, the control means 22 is activated to reduce the light transmittance of the two-layer G)-1 type liquid crystal probe 15, dimming the illumination light from the headlamp 11, and turning on the high beam. Even when the low beam filament 14b is lit, the illumination light is the same as when the low beam filament l-14a is lit. Therefore, only when the low beam filament 14a is broken, the light transmittance of the liquid crystal element is lowered to dim the light, and when the high beam filament 14b is broken, the control is not performed.

Incidentally, which filament is in the operating state is constantly detected by the detection circuit 24, and the above-mentioned control is performed based on this detection signal.

〔Effect of the invention〕

As explained above, the headlamp reserve lighting system according to the present invention has a two-layer GH type liquid crystal element disposed in front of the headlamp lens as a dimming means, and low beam and high beam filaments disposed inside the headlamp. and a switching i,1lt111 circuit that performs reserve control based on the signal from the detection means, and when the low beam filament is disconnected, the high beam filament is turned on and the two-layer GH type liquid crystal element is simultaneously illuminated. This is a configuration that controls the transmittance to be lowered, and does not require any oscillation circuit or series resistor as in the conventional example, making the configuration simple and allowing adjustment of the degree to which the transmittance is lowered, that is, the transmittance is variable. Since it is a dimming method, it has the excellent effect of providing any required illumination light.

In addition, only a switching control circuit is required as the circuit configuration for control, eliminating the adverse effects of noise and heat generation, and significantly reducing the failure rate of the system.

[Brief explanation of drawings]

Figure 1 is an explicit side view of the headlamp used in the system of the present invention, Figure 2 is an explicit illustration of the two-layer GH type liquid crystal thread attached to the front of the headlamp, and Figure 3 is An explicit circuit diagram of the system of the present invention, FIG. 4 is an explicit circuit diagram of a conventional reserve lighting system, 1 of FIG.
(2) is a circuit diagram of two examples showing only the main parts in the circuit diagram. 11...Headlamp 12...Reflector-13...Lens 14...
...Bulb 14a...Low beam filament 14b...High beam filament 15.
...Two-layer G H-type liquid crystal element 16...Glass plate 17...Electrode 18...Liquid crystal 19...AC signal generator 20.・・・
...Filament breakage detection sensor 21...
・Switching control circuit 22...Transmittance control means 23...Double dimmer switch Patent applicant
Agent of Sukunley Electric Co., Ltd.
Teruo Akimoto ”! Engraving of the drawing (no changes to the content) S Figure 3 ■ F0r 1 Tobi “; City procedures It) Main gate (method) % formula % 2, Name of the invention Reserve lighting system for headlamps 3 , Relationship to the case of the person making the amendment Applicant Name (230) Stanley Electric Co., Ltd. 4
, agent

Claims (1)

[Claims] A headlamp equipped with a two-layer GH type liquid crystal element on the front surface of the lens and having filaments for low and high beams;
means for detecting breakage of both filaments; a switching control circuit for reserve control; means for detecting the usage state of the filaments; and lighting the high beam filament via the switching circuit when the low beam filament is broken. At the same time, the two layers G
A reserve lighting system for a headlamp, comprising a control means for controlling the transmittance of an H-type liquid crystal element to be lowered.