JPH056507U - Discharge lamp headlight - Google Patents

Abstract

(57) [Abstract] [Purpose] In a headlamp that uses a discharge lamp as a conventional light source, when a lens is damaged due to an unexpected accident, the discharge lamp to which a high voltage is applied is exposed, which causes electric shock. There is a problem that causes a secondary disaster such as an accident, and we will try to solve this problem. A conductive circuit 7 integrated with the lens 5 of the headlight 1 is laid on the inner surface of the lens 5, and a lighting circuit 6 of the discharge lamp 4 detects the presence of a current flowing through the conductive circuit 7. By using the discharge lamp 4 whose operation is performed by the circuit 8 as the headlight 1 having the light source as the light source, the conductive circuit 7 is broken at the same time when the lens 5 is broken, and the broken lamp is supplied to the discharge lamp 4. The high voltage is cut off to prevent an electric shock accident and solve the problem.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vehicle headlamp, and more particularly to a headlamp that uses a discharge lamp such as a metal halide lamp as a light source.

[0002]

[Prior Art]

 FIG. 3 shows an example of a conventional headlight 90 of this type. A discharge lamp 93 such as a metal halide lamp is arranged in a housing 92 provided with a reflecting mirror 91, and the front surface of the housing 92 is It is supposed to be covered with a lens 94 formed of a transparent member such as glass. At this time, since the discharge lamp 93 cannot be lit by a DC 12 V power source which is normally used for automobiles, a lighting circuit 95 including, for example, an inverter and an igniter is attached, A sufficiently high voltage is supplied for lighting.

[0003]

[Problems to be solved by the device]

 However, in the above-described conventional headlight 90, when a collision accident or the like occurs and the lens 94 is damaged and the discharge lamp 93 is exposed, the discharge lamp 93 is applied for lighting. There is a risk of secondary accidents such as touching high voltage and electric shock, and the solution to this point was an issue.

[0004]

[Means for Solving the Problems]

 As a concrete means for solving the above-mentioned conventional problems, the present invention is a headlamp including a discharge lamp as a light source, wherein the lens is integrated with the lens on the inner surface of the lens of the headlamp. Provided is a discharge lamp headlamp, wherein a conductive circuit is laid, and a lighting circuit of the discharge lamp is operated by a detection circuit which detects the presence of a current flowing through the conductive circuit. By doing so, it is possible to prevent the occurrence of electric shock accidents and solve the problems.

[0005]

【Example】

 Next, the present invention will be described in detail based on an embodiment shown in the drawings. Reference numeral 1 in FIG. 1 is a headlight, and a housing 2 of the headlight 1 accommodates a reflection mirror 3 and a discharge lamp 4, and the front surface of the housing 2 is covered with a lens 5. As in the conventional example, the discharge lamp 4 is hermetically sealed and connected to the lighting circuit 6 which is composed of, for example, an inverter 6a and an igniter 6b so that it can be lit.

However, according to the present invention, the conductive circuit 7 is formed on the inner surface of the lens 5 to have a suitable shape such as a line crossing the surface of the lens 5 so as to be in close contact with the lens 5 by appropriate means such as vapor deposition and printing. A low-voltage direct current, which is the power source of the automobile, is supplied to the conductive circuit 7 through the illumination lamp switch SW.

At the same time, the conducting circuit 7 is connected to a detecting circuit 8 such as a coil 8a of a relay for detecting that a current is flowing through the conducting circuit 7, and the output of the detecting circuit 8, that is, the relay contact 8b. Is designed to supply power to the lighting circuit 6 by the operation of the detection circuit 8.

Here, the conductive circuit 7 will be described in more detail. Since the conductive circuit 7 is laid in order to detect breakage of the lens 5, for example, a wire is not attached. It is not suitable, and it is preferable to integrate it with the lens 5 as much as possible and to break at the same time when it breaks. Also, in order not to impair the characteristics of the lens 5, it should be thin or transparent. Is preferred.

Next, the operation and effect of the present invention having the above-described structure will be described. A conductive circuit 7 is provided integrally with the lens 5 and a lighting circuit is provided by the presence of a current flowing through the conductive circuit 7. When the lens 5 is damaged due to an unforeseen accident and the discharge lamp 4 to which a high voltage is applied is exposed due to the operation of the lens 6, the lens 5 is damaged and the conductive circuit is simultaneously formed. 7 also breaks, and the power supply to the lighting circuit 6 is cut off by the operation of the detection circuit 8 to prevent the occurrence of a secondary electric shock accident.

Incidentally, in actual practice, a resin member has been adopted as a member for forming the lens 5 in recent years, and it is partially damaged as compared with a glass member which has been conventionally used. In that case, since the exposure of the discharge lamp 4 may not be detected, a plurality of conductive circuits 7 are laid on the surface of the lens 5 as shown in FIG. 2, and the conductive circuits are connected by, for example, an AND gate 9. It is possible to freely make a change such as cutting off the power supply to the lighting circuit 6 when any one of the wires 7 breaks.

[0011]

[Effect of the device]

 As described above, according to the present invention, a conductive circuit integrated with the lens of the headlight is laid on the inner surface of the lens, and the lighting circuit of the discharge lamp detects the presence of current flowing through the conductive circuit. By using a discharge lamp headlamp that operates by a detection circuit, even if the discharge lamp is exposed due to lens damage due to an unexpected collision accident, the conductive circuit that breaks together with the lens will supply power to the lighting circuit. By shutting off and preventing secondary accidents such as electric shock accidents, it has an excellent effect in improving the safety of this type of headlight.

[Brief description of drawings]

FIG. 1 is a schematic circuit diagram showing an embodiment of a discharge lamp headlamp according to the present invention.

FIG. 2 is a schematic circuit diagram showing the essential part of another embodiment of the present invention.

FIG. 3 is a schematic circuit diagram showing a conventional example.

[Explanation of symbols]

 1 ... Headlight 2 ... Housing 3 ... Reflector 4 ... Discharge lamp 5 ... Lens 6 ... Lighting circuit 6a ... Inverter, 6b ... Igniter 7 ... Conductive circuit 8 ... Detection circuit 9 ... … AND gate

Front page continuation (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location F21V 25/04 2113-3K H05B 41/16 X 7913-3K 41/24 G 7913-3K

Claims (1)

[Claim 1] In a headlight comprising a discharge lamp as a light source, a conductive circuit integrated with the lens is laid on the inner surface of the lens of the headlight. The discharge lamp headlamp, wherein the lighting circuit of the discharge lamp is operated by a detection circuit that detects the presence of a current flowing through the conductive circuit.