JPH0251776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to a stop lamp system abnormality detection system that detects the occurrence of an abnormality in the circuit system of a stop lamp that lights up when the brakes of an automobile are operated.

Prior Art Conventionally, a system for detecting whether or not there is an abnormality in the stop lamp system during the start-up inspection of an automobile has been configured as shown in Fig. 3.
When the battery switch BAT-SW is turned on and the main switch M-SW is turned on (at this time, the ignition switch IG-SW is in the off position a), if the stop lamp STP-LMP is not out of bulb, the pilot lamp P is turned on. - Check that LMP is normal by lighting it, then operate the brake and switch the brake switch.
When BK-SW turns on normally, current stops flowing to the pilot lamp P-LMP, which has a higher resistance than the stop lamp STP-LMP, and the light goes out, causing the brake switch BK to turn off.
- An operation check of the SW is performed (see Japanese Patent Publication No. 51-20709).

However, in such conventional stop lamp system abnormality detection systems, the check is performed when the engine is stopped, which results in battery consumption.

Purpose The present invention was made in consideration of the above points, and
To provide a stop lamp system abnormality detection system which checks the operation of a stop lamp circuit under the operating state of an engine and easily determines whether an abnormality has occurred in the stop lamp circuit.

Configuration An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In the stop lamp system abnormality detection system according to the present invention, as shown in FIG. 1, the stop lamp STP-LMP is turned on via the brake switch BK-SW whose contacts are closed when the vehicle's brakes are operated. circuit 1
A relay switch RL-SW is provided inside, and when the relay contact opens when an abnormality such as a bulb breakage or wire breakage occurs in the stop lamp STP-LMP, the driver DRIV in the alarm lamp circuit 2 lights up the alarm lamp ALM-LMP. A lighting command is given to the transistor Q, which serves as a control switch element for turning off the light, to light up the alarm lamp ALM-LMP, and an ignition is also provided to check the operation of the alarm lamp ALM-LMP and the brake switch BK-SW. Shion switch IG-SW
and a control circuit 3 for controlling lighting and extinguishing of alarm lamps ALM-LMP in accordance with the operating state of brake switch BK-SW.

This control circuit 3 has an RS flip-flop function, and is connected to the ignition switch IG-SW.
When is turned on, it enters the set state, and the output signal S at that time becomes low level and the alarm lamp ALM is turned on.
- Directly form the power supply circuit for LMP and turn it on. Then, when the brake switch BK-SW is turned on, it enters the reset state, and the output signal S at that time becomes high level and the alarm lamp ALM-LMP is turned on.
disconnect the power supply circuit to turn off the light.

At this time, when a failure occurs in the brake switch BK-SW, the control circuit 3 is not reset at all, and the warning lamp ALM-LMP is not turned off.

FIG. 2 shows a specific configuration example of the control circuit 3 and driver DRIV.

In the configuration shown in FIG. 2, the operation when the stop lamp circuit 1 is normal will now be described.

First, when the ignition switch IG-SW is closed (at this time, the brake switch BK-SW is in the off state), the resistor R6 in the control circuit 3
The base current flows to the transistor Q3 through the circuit of the diode D5 and the transistor Q
3 is in the on state, which causes the driver DRIV
diode D6 and transistor Q regardless of
Alarm lamp in alarm lamp circuit 2 through 3
ALM-LMP power supply circuit is formed and it lights up. At this time, the transistor Q2 in the control circuit 3 is in an off state because a large time constant is set in a timer circuit comprising a resistor R5 and a capacitor C2 on its base side. Also, at that time, the ignition switch IG
- When SW is closed, transistor Q1 is in the on state, so that A in the alarm lamp circuit 2 is
The points are shorted through the relay switch RL-SW and the stop lamp STP-LMP and the driver
The input signal of DRIV becomes low level, so the driver DRIV itself does not turn on the alarm lamp ALM−.
No lighting command is given to LMP.

Next, when the brake switch BK-SW in the stop lamp circuit 1 is turned on by operating the brake within the set time of the previous timer circuit, the resistor R3
A base current momentarily flows into the transistor Q2 through the circuit of the capacitor C1, keeping the transistor Q2 in the on state, and thereby short-circuiting the base side of the transistor Q3, turning the transistor Q3 off. As a result, the power supply circuit for the alarm lamps ALM-LMP in the alarm lamp circuit 2 is suddenly cut off and the lights are turned off. In addition, in that case,
When brake switch BK-SW is turned on, transistor Q1 is turned off, but relay switch RL-
Since the relay coil of the SW is energized and closes its relay contact, point A in the alarm lamp circuit 2 is short-circuited through the relay contact and the driver
The input signal of DRIV becomes low level, so the driver DRIV itself does not turn on the alarm lamp ALM−.
No lighting command is given to LMP.

Therefore, when starting the engine, turn on the ignition switch IG-SW and turn on the warning lamp.
By turning on ALM-LMP and then turning off the warning lamp ALM-LMP by operating the brakes, it is possible to check that the warning lamp ALM-LMP and brake switch BK-SW are operating normally. become.

In addition, after the check is completed, the brake switch BK
Even if the -SW is turned off, the transistor Q1 is turned on, forcing the point A in the alarm lamp circuit 2 to a low level, and keeping the alarm lamp ALM-LMP in the off state.

Next, the operation when an abnormality occurs in the stop lamp circuit 1 will be described below.

First, when the brake switch BK-SW is out of order, the warning lamp ALM-LMP remains lit without being extinguished even if the brake is operated after the ignition switch IG-SW is closed. That is, when the brake switch BK-SW is open and malfunctions, no on signal is given to the transistor Q2 through the brake switch BK-SW even if the brake is operated, and therefore the transistor Q3 is turned on. It will continue to be retained.

Also, if the brake switch BK-SW is closed and malfunctions, the capacitor C has already been turned on before the ignition switch IG-SW is turned on.
1 is in a charged state, even if the brake is operated, no on signal is given to the transistor Q2, and therefore the transistor Q3 continues to be kept in the on state.

Also, the fuse F in the stop lamp circuit 1
When the ignition switch IG-SW is disconnected, the circuit at point B is disconnected, or the stop lamp STP-LMP is blown out, the alarm lamp will be turned on because transistor Q1 is in the OFF state in all of these cases. Point A in circuit 2 becomes high level, so the warning lamp ALM-LMP lights up via the driver DRIV, but even if the brake is operated and the brake switch BK-SW is turned on after that, the level at point A does not change at all. The alarm lamp ALM-LMP remains lit.

In this way, even if you close the ignition switch IG-SW and turn on the warning lamp ALM-LMP, and then operate the brakes, the warning lamp ALM-LMP will not turn on.
Since the lamp does not turn off, the stop lamp circuit 1
Brake switch BK-SW failure, stop lamp STP-LMP bulb blown, fuse F
This makes it possible to reliably detect the occurrence of abnormalities such as disconnections in circuits or disconnections in circuits. Since the check is performed while the engine is running, the battery will not be consumed, and the occurrence of an abnormality in the stop lamp circuit 1 can be detected not only during the initial inspection but also while the vehicle is running. It has become a thing.

In the embodiment shown in Fig. 2, the alarm lamp
A lamp check switch CK-SW (push button switch) is separately provided to arbitrarily check whether the ALM-LMP is out of bulb.

Effects As described above, in the stop lamp system abnormality detection system according to the present invention, the power supply circuit for the alarm lamp is formed by closing the ignition switch, and the alarm lamp is turned on for the time set by the timer. a control circuit that cuts off a power supply circuit for the warning lamp and turns off the warning lamp when a brake switch provided in the stop lamp circuit is turned on when a brake is operated within a set time; A driver that gives an early warning lamp lighting command to a control switch element that turns on and off the warning lamp in response to the operation of the relay contact when the relay coil installed in the stop lamp circuit is deenergized due to disconnection of the stop lamp circuit. It has the excellent advantage of being able to check the operation of the stop lamp circuit under the operating conditions of the engine and easily detect abnormal conditions in the stop lamp circuit. .

[Brief explanation of drawings]

FIG. 1 is a simplified circuit configuration diagram showing an embodiment of the stop lamp system abnormality detection system according to the present invention;
FIG. 2 is a diagram showing a specific circuit configuration example in the same embodiment, and FIG. 3 is a circuit diagram showing a conventional stop lamp system abnormality detection system. 1...Stop lamp circuit, 2...Warning lamp circuit, 3...Control circuit, STP-LMP...Stop lamp, BK-SW...Brake switch, RL
-SW...Relay switch, DRIV...Driver,
ALM-LMP...Alarm lamp, Q...Control switch element.

Claims (1)

[Claims] 1. When the ignition switch is closed, a power supply circuit for the alarm lamp is formed, and the alarm lamp is turned on for the time set by the timer, and then, when the brake is operated within the time set by the timer, a power supply circuit is formed in the stop lamp circuit. When the brake switch is turned on, the control circuit cuts off the power supply circuit of the alarm lamp and turns off the alarm lamp, and the relay coil installed in the stop lamp circuit turns off the alarm lamp when the stop lamp circuit is disconnected. A stop lamp system abnormality detection system is comprised of a driver that applies a lighting command for a pre-warning lamp to a control switch element that turns on and off the warning lamp in accordance with the operation of a relay contact when the warning lamp is turned on and off.