JP3031733B2 - Vehicle lamp control circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp control circuit, and more particularly, to a control circuit having a function of preventing a vehicular illumination lamp from being turned off.

[0002]

2. Description of the Related Art As a conventional device of this type, for example, Japanese Patent Publication No. Sho 56-3210, a relay contact provided between a manual open / close switch and a load is opened upon receiving an open signal of an ignition circuit. Things are shown. As a specific circuit, an open-collector transistor that drives a flip-flop and a relay coil is used. Also,
Japanese Utility Model Laid-Open Publication No. 63-24028 discloses an automatic lighting device in which an illumination lamp is turned off in accordance with the state of a door open / close detection switch, a lighting switch, an ignition switch, and the like. As a specific circuit,
An open collector transistor for driving a flip-flop, a hysteresis circuit, and a relay coil is used.

[0003]

However, all of the above-mentioned conventional devices use an open-collector output transistor for driving a relay coil and turn off the transistor to automatically turn off the light regardless of the position of the lighting switch. Was like that. For this reason, if the transistor fails and remains off while the vehicle is running, or if the transistor is turned off due to a logic circuit failure, the lighting lamp suddenly goes off while the vehicle is running. Therefore, there was a problem that safety considerations were lacking. In addition, all of the above-described conventional devices require a large number of components such as flip-flops, hysteresis circuits, and power supply circuits for them, and there is a problem that miniaturization of the devices is limited. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the first invention is to provide a lighting lamp that can be used even if an output transistor fails or a logic circuit fails during running of a vehicle. An object of the present invention is to provide a highly safe vehicle lamp control circuit having a fail-safe function that does not suddenly turn off. Another object of the second invention is to provide a vehicle lamp control circuit which can reduce the number of parts of a vehicle lamp control circuit having an automatic light-off function and can be integrated into a very small unit. .

[0004]

In order to achieve the above object, according to the present invention, as a first invention, the connection between lamps 7, 8, and 9 and power supply 1 is turned on and off as illustrated in the drawings of the embodiments. Lamp relays 4 and 5; a lighting switch 13 connected in series with the coils of the lamp relays 4 and 5 to turn on and off a connection to a ground line; and a serial connection between the coils of the lamp relays 4 and 5 and the power supply 1. Connected power 1
And a lighting control circuit 20 for controlling the driving transistor Q5 to turn on and off based on signals from the lighting switch 13, the ignition switch 3, the door switch 14, and the like.
And the coil of the lamp relays 4 and 5 is bypassed by the drive transistor Q5 and the ignition switch 3
Bypass diode D13 connected to power supply 1 via
And a lamp control circuit for a vehicle.

As a second invention, lamp relays 4 and 5 for turning on and off the connection between lamps 7, 8, and 9 and power supply 1, and lamp relays 4,
And a driving transistor connected in series between the coils of the lamp relays 4 and 5 and the power supply 1 to turn on and off the connection with the power supply 1. Q5 and P
The collector and base of NP transistor Q2 and NPN transistor Q1 are connected to each other via a resistor, and PNP
The emitter of the transistor Q2 is connected to the power supply 22, and the emitter of the NPN transistor Q1 is connected to the common line 2.
4 connected to the first self-holding circuits Q1, Q2
And a PNP transistor Q4 and an NPN transistor Q3
And the collector and base are connected to each other via a resistor,
A second self-holding circuit Q constructed by connecting the emitter of PNP transistor Q4 to power supply 22 and connecting the emitter of NPN transistor Q3 to common line 24.
3, Q4 and the self-holding circuits Q1, Q2, Q3, Q4
Means D12 for connecting the common line 24 to the lighting switch 13 and connecting the common line 24 to the ground line when the lighting switch 13 is on, and the common line 24 for the self-holding circuits Q1, Q2, Q3 and Q4.
Is connected to the ground line, the one-shot circuit C2 that turns on the second self-holding circuits Q3 and Q4.
Means D5, R5 and means D3, R1, D4 for releasing the self-holding of the second self-holding circuits Q3, Q4 by turning on the first self-holding circuits Q1, Q2 when the ignition switch 3 is on. R8, means D2 for releasing the self-holding of the first self-holding circuits Q1 and Q2 when the door switch 14 is on, and the two sets of self-holding circuits Q
Means D7, D7 for turning on the drive transistor Q5 when any one of Q1, Q2, Q3, Q4 is on.
8 and R13 are provided.

[0006]

In the vehicle lamp control circuit according to the first aspect of the present invention, even if the drive transistor Q5 is turned off due to the failure of the drive transistor Q5 or the lighting control circuit 20, the vehicle is not driven. When the ignition switch 3 is turned on, current is supplied from the ignition switch 3 to the coils of the lamp relays 4 and 5 via the bypass diode D13, and the lighting of the lamps 4 and 5 is continued.

Further, in the vehicle lamp control circuit according to the second aspect of the present invention, when the lighting switch 13 is turned on even when the ignition switch 3 is off, the common line 24 is connected to the ground line. Sometimes, the second self-holding circuits Q3, Q4 are turned on by the one-shot circuits C2, D5, R5, and the lamps 7, 8, 9
Lights up. Next, when the ignition switch 3 is turned on for operation, the first self-holding circuits Q1 and Q2 are turned on, and the self-holding of the second self-holding circuits Q3 and Q4 is released. At this time, the first self-holding circuits Q1, Q2
Are turned on, the lamps 7, 8, 9 continue to light. Next, even when the operation is terminated and the ignition switch 3 is turned off, the first self-holding circuits Q1, Q2 continue to be on, and the lamps 7, 8, 9 continue to light. Next, when the driver opens the door to leave the car, the door switch 14 is turned on, the self-holding of the first self-holding circuits Q1, Q2 is released, and the lamps 7, 8, 9 are automatically turned off.

[0008]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram showing a vehicle lamp control circuit.
The negative electrode of the vehicle power supply battery 1 is grounded, and the positive electrode is connected via a fuse 2 to a third terminal of the automatic light-off unit 20, an ignition switch 3, a contact 4A of a headlamp relay 4,
It is connected to the contact 5A of the tail lamp relay 5 and the door lamp 6. The upper headlamp 7 and the lower headlamp 8 connected to the contact 4A of the headlamp relay 4 are connected via a connector 10 to a dimmer switch 11 for switching between an H beam and an L beam. The other end of the tail lamp 9 connected to the contact 5A of the tail lamp relay 5 is grounded. One end of the coil of the headlamp relay 4 is connected to the seventh terminal of the automatic light-off unit 20, and the other end is connected to the passing switch 12 and the lighting switch 13 via the connector 10 and to the second terminal of the automatic light-off unit 20. doing. One end of the coil of the tail lamp relay 5 is connected to the sixth terminal of the automatic light-off unit 20,
The other end is connected to the lighting switch 13 via the connector 10.
And to the first terminal of the automatic light-off unit 20.

The lighting switch 13 has three switch positions: a head lamp position (HEAD), a tail lamp position (TAIL), and an off position (OFF). In the head lamp position, the coils of the head lamp relay 4 and the tail lamp relay 5 are grounded. In the tail lamp position, only the coil of the tail lamp relay 5 is connected to the ground, and all are opened in the off position. The door lamp 6 connected to the positive electrode of the power supply battery 1 is connected to the door switch 14 via the diode D30. One end of the door switch 14 is connected to the seventh terminal of the automatic light-off unit 20, and the other end is grounded. . Reference numerals 16 and 17 are fuses.

The automatic light-off unit 20 uses a line connected to a third terminal via a diode D9 as a power supply line 22,
The line connected to the first terminal via the diode D12 is configured as a common line 24 to be grounded. The main elements are a PNP transistor Q2 and an NPN transistor Q
1 and the base thereof are connected to each other via resistors R2 and R4, the emitter of the PNP transistor Q2 is connected to the power supply line 22, and the NPN transistor Q1
Connected to the common line 24 in the first
Self-holding circuits Q1 and Q2 and a PNP transistor Q4
And the collector and base of the NPN transistor Q3 are connected to each other via resistors R8, R9 and R10, the emitter of the PNP transistor Q4 is connected to the power supply line 22, and the emitter of the NPN transistor Q3 is connected to the common line 24. Self-holding circuit Q3,
Q4 and a drive transistor Q5 connected in series between the coils of the lamp relays 4 and 5 and the power supply battery 1 to turn on and off the connection with the power supply battery 1.

The common line 24 is connected to the lighting switch 13 via the first terminal, and the diode D12 for grounding the common line 24 when the lighting switch 13 is on, and the common line 24 are grounded. Sometimes a one-shot circuit including a capacitor C2, a diode D5, and a resistor R5 for turning on the second self-holding circuits Q3, Q4 is provided. Further, when the ignition switch 3 is turned on, the first self-holding circuits Q1, Q
A diode D3 and a resistor R1 for turning ON
And a diode D4 and a resistor R8 for simultaneously releasing the self-holding of the second self-holding circuits Q3 and Q4. When the door switch 14 is on, the self-holding of the first self-holding circuits Q1 and Q2 is provided. Diodes D2 and D for releasing holding
1 is provided. The two sets of self-holding circuits Q1, Q2
Alternatively, to turn on the drive transistor Q5 when any of Q3 and Q4 is on, the diode D7,
D8 and the resistor 13 are connected.

Then, the drive transistor Q5 is bypassed to the collector of the drive transistor Q5 for driving the coils of the lamp relays 4 and 5, and the coils of the lamp relays 4 and 5 are connected to the power supply battery 1 via the ignition switch 3. The bypass diode D13 is connected.

The operation based on the above configuration will be described. 2 and 3 are timing charts for explaining the operation. Referring to FIG. 2, the driver's seat door is closed (door switch 1).
When the lighting switch 13 is turned on with the ignition switch 3 turned on while the ignition switch 3 is turned on, the lamp 7,
8, 9 light up (101 in the figure). This is because the common line 24 is grounded, a base current is supplied from the ignition switch 3 to the transistor Q1 via the diode D3 and the resistor R1, the transistor Q1 is turned on, the transistor Q2 is also turned on, and the first self-holding circuit Q1 is turned on. , Q2 are self-held. As a result, the diode D8 and the resistor R1
This is because the base current of the driving transistor Q5 is attracted via the switching transistor 3, and the driving transistor Q5 is turned on to turn on the lamp relays 4 and 5. Next, even if the ignition switch 3 is turned off (102 in FIG.
Lamps 7, 8, and 9 remain lit because the self-holding circuits Q1 and Q2 continue self-holding.

Next, the driver's seat door is opened and the door switch 14 is opened.
Is turned on, the lamps 7, 8, and 9 are turned off automatically (1 in FIG.
03). This is because the collector current of the transistor Q2 is connected to the resistor R4 and the diode D2 and grounded to the door switch 1.
4, the base current of the transistor Q1 is cut off, the self-holding of the first self-holding circuits Q1, Q2 is released, and the driving transistor Q5 flowing through the diode D8
Is cut off, and the driving transistor Q5 is turned off. When the ignition switch 3 is turned on during the automatic light extinguishing (104 in the figure), the first self-holding circuits Q1 and Q2 are again self-held and the lamps 7, 8, and 9 are turned on.
Lighting is restarted. Next, the driver's seat door was opened (see FIG. 1).
05) Even if the driver's seat door is opened and closed during the automatic light-off (106 in the figure), the lamps 7, 8, and 9 remain automatically turned off.

When the driver's seat door is closed (the door switch 14 is turned off) and the lighting switch 13 is once turned off and then turned on while the lights are being automatically turned off, the lamps 7, 8, and 9 are turned on (illustration 107). This is because the capacitor C2 is connected to the diode D5 and the resistor R while the lighting switch 13 is off.
5 discharges. Next, immediately after the lighting switch 13 is turned on and the common line 24 is grounded, a charging current flows from the emitter of the transistor Q4 to the capacitor C2 via the base, the resistors R8 and R6, turning on the transistor Q4 and turning on the transistor Q4. Supplies the base current of transistor Q3. As a result, the second self-holding circuits Q3 and Q4 are self-held, and the drive transistor Q5 is turned on to turn on the lamps 7, 8,
This is because the lighting of 9 is restarted.

A description will be given with reference to FIG. The ignition switch 3 is on, the lighting switch 13 is on,
When the driver's seat door is opened (illustrated 202) from the state in which the driver's seat door is closed (illustrated 201), the lamps 7, 8, and 9 are turned on when the ignition switch 3 is turned off (illustrated 203).
Turns off automatically. This is because when the driver's door is opened and the door switch 14 is turned on, the base current from the transistor Q2 to the transistor Q1 via the diode D1 is cut off. However, while the ignition switch 3 is on, the diode D3 and the resistor The base current of the transistor Q1 is supplied via R1, and the transistors Q1, Q
2 keeps the ON state, and the lighting of the lamps 7, 8, 9 is maintained. However, when the ignition switch 3 is turned off with the driver's seat door open, the base current passing from the ignition switch 3 through the diode D3 is cut off, and the transistors Q1 and Q2 change to the off state, and the transistor Q1 and Q2 are turned off. This is because the supplied base current of the driving transistor Q5 is cut off and the driving transistor Q5 is turned off, and as a result, the lamps 7, 8, and 9 are automatically turned off.

When the ignition switch 3 is turned on while the lights are automatically turned off, the lamps 7, 8, and 9 are turned on (see FIG. 20).
4) When the ignition switch 3 is turned off and the driver's seat door is opened, the lamps 7, 8, and 9 are turned off automatically (see FIG. 20).
5).

Even when the ignition switch 3 is off and the driver's door is open (the door switch 14 is on) and the light is automatically turned off (shown at 206), if the lighting switch 13 is turned off and then on, the lamps 7, 8, and 9 are turned on. Lights up (207 in the figure). This is because the second self-holding circuits Q3 and Q4 are self-held and lighting of the lamps 7, 8, and 9 is resumed, as described in the illustration 107 of FIG. Next, even if the ignition switch 3 is turned on, the lamp 7,
8 and 9 remain lit (208 in the figure). this is,
When the ignition switch 3 is turned on, the voltage of the power supply battery 1 is applied to the base of the transistor Q4 via the diode D4 and the resistor R8, and the transistor Q4 is turned off to self-hold the second self-holding circuits Q3 and Q4. Is released. However, at the same time, the base current is supplied to the transistor Q1 via the diode D3 and the resistor R1, and the transistor Q1 is turned on, so that the first self-holding circuit Q
1, Q2 are self-held. Therefore, the diode D7
, A base current is supplied to the driving transistor Q5, the on state of the driving transistor Q5 is maintained, and the lamps 7, 8, and 9 remain lit.

Next, the driver's seat door is opened (door switch 14).
When the ignition switch 3 is turned off, the lamps 7, 8, and 9 are automatically turned off even when the lighting switch 13 is turned on and the lighting switch 13 is turned on (illustration 209). This is because when the ignition switch 3 is turned off, the diode D
3. No base current is supplied to the transistor Q1 via the resistor R1, and the diode D1 and the resistor R
2, the base current also flows from the door switch 14 to the ground, the base current is not supplied to the transistor Q1, and the transistor Q1 is turned off. As a result, the base current of the driving transistor Q5 supplied via the diode D8 is cut off, the driving transistor Q5 is turned off, and the lamps 7, 8, and 9 are automatically turned off.

Transistors Q1, Q2, Q3, Q4 for realizing the above-described sequence function of automatic turning off.
In the present embodiment, in addition to Q5, a bypass diode D13 that bypasses the drive transistor Q5 is provided.
Therefore, when the ignition switch 3 is turned on, the voltage of the power supply battery 1 is applied to the coils of the relays 4 and 5 via the bypass diode D13 regardless of the state of the driving transistor Q5, and the lighting switch 1 is turned on.
When the switch 3 is turned on, the lamps 7, 8, and 9 are turned on unconditionally. Therefore, even if the drive transistor Q5 fails during running of the vehicle or the logic circuits such as the self-holding circuits Q1 and Q2 fail, the illumination lamps 7, 8, and 9 do not suddenly turn off and have a fail-safe function. , Very safe.

Further, in this embodiment, only five transistors Q1, Q2, Q3, Q4, Q5 are used in order to realize the above-mentioned complex automatic light-off sequence function.
Further, since the vehicle battery 1 is used as it is as the power source, the number of parts of the automatic light-off unit 20 is extremely small. For this reason, even if the automatic light-off unit 20 is formed as a discrete component without using an IC, it can be molded as a terminal socket-shaped component having a size of several centimeters, and mounting in a vehicle becomes extremely easy.

[0022]

According to the first aspect of the present invention, which has the above-described configuration and includes a bypass diode, it is possible to ensure that the illumination lamp is lit while the vehicle is running even if the output transistor or the like fails. Yes, it has a fail-safe function,
There is an excellent effect that the safety is extremely high. Further, the second invention has an excellent effect that the number of parts of a vehicle lamp control circuit having an automatic light-off function for realizing a complicated sequence function can be reduced, and can be integrated into a very small unit.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a preferred embodiment of the present invention;

FIG. 2 is a timing chart illustrating the operation of an automatic light-off function,

FIG. 3 is a timing chart illustrating an operation.

[Explanation of symbols]

1. . Power battery, 3. . Ignition switch,
4,5. . Lamp relay, 7,8. . head lamp,
9. . 12. tail lamp; . 13. lighting switch; . Door switch, 20. . Automatic light-off unit, D13. . Bypass diode, Q1, Q
2. . The first holding circuit, Q3, Q4. . First holding circuit, Q5. . Driving transistor, C2, D5, R
5. . One shot circuit.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunimitsu Hisatomi 1 Kakihata, Inuyama-shi, Aichi Pref. Imasen Electric Works, Ltd. (56) References Shokai Sho 62-145844 (JP, U) Shokai Sho53 -76449 (JP, U) Actually open 1979-64439 (JP, U) Actually open 56-122298 (JP, U) Actually open 1984-29,530 (JP, U) Real public 1988-24028 (JP, Y2) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60Q 11/00 645 B60Q 1/04

Claims (2)

(57) [Claims] 1. A lamp relay for turning on and off a connection between a lamp and a power supply, a lighting switch connected in series with a coil of the lamp relay for turning on and off a connection to a ground line, and a switch between the coil of the lamp relay and a power supply. A driving transistor connected in series to turn on and off a connection with a power supply; a lighting control circuit that controls on / off of the driving transistor based on a signal from the lighting switch, an ignition switch, a door switch, etc .; And a bypass diode for connecting a coil of the lamp relay to a power supply via the ignition switch. 2. A lamp relay for turning on and off a connection between a lamp and a power supply, a lighting switch connected in series with a coil of the lamp relay for turning on and off a connection to a ground line, and a switch between the coil of the lamp relay and a power supply. And a collector and a base of a PNP transistor and an NPN transistor connected to each other via a resistor, and
Connect the emitter of the P transistor to the power supply and
A first self-holding circuit formed by connecting the emitter of the PN transistor to a common line, the collector and the base of the PNP transistor and the NPN transistor being connected to each other via a resistor, and the emitter of the PNP transistor being connected to a power supply A second self-holding circuit configured by connecting the emitter of the NPN transistor to a common line; and connecting the common line of the self-holding circuit to the writing switch, and connecting the common line when the writing switch is on. Means for connecting to a ground line, a one-shot circuit for turning on the second self-holding circuit when the common line of the self-holding circuit is connected to the ground line, and a one-shot circuit for turning on the second self-holding circuit when the ignition switch is on. The first self-holding circuit is turned on to release the self-holding of the second self-holding circuit. Means for releasing self-holding of the first self-holding circuit when the door switch is on, and turning on the drive transistor when one of the two sets of self-holding circuits is on. Means for controlling a vehicle lamp.