JPS586987B2 - warning display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a warning display device, and more particularly to a warning display device that controls the amount of light emitted from a warning display pilot lamp of an automobile at two levels.

Generally, the electrical system of an automobile is equipped with a pilot lamp that warns the driver when the operation of each part (monitored electrical component) is abnormal.

For example, it is used to display a warning about a break in a stop lamp or an abnormality in the oil level.

In this case, the configuration is such that abnormalities in the pilot lamp itself can also be detected.

However, pilot lamps that are turned on relatively frequently for the purpose of self-checking have the disadvantage that the amount of light emitted is enough to warn the driver even in the daytime, but it feels dazzling at night, impeding safe driving.

In view of the above points, the present invention has been made to solve such problems and eliminate such drawbacks, and its purpose is to change the amount of light emitted from the pilot lamp depending on the day and night conditions and to check the amount of light emitted from the pilot lamp. If there is an abnormality in a circuit, it can be used as a warning even at night using the amount of light emitted during the day, and the pilot lamp can also be used to display abnormalities in multiple circuits. If you turn off the lights in the opposite way, you can use the pilot light to get out of the way.Furthermore, if the taillight or headlamp breaks during the day, the pilot light will turn on dimly, so when you self-check the pilot light, you can check whether the taillight or headlamp is broken. The object of the present invention is to provide a warning display device that can detect the warning.

In order to achieve these objectives, the present invention provides a stop lamp connected in series to a power source and a stop lamp that is turned on. A disconnection detection section detects disconnection of the stop lamp by inputting the connection point potential with the stop lamp switch that controls turning off the light, a switching circuit that controls the pilot lamp based on the output of this disconnection detection section, and a switching circuit that controls the current of this switching circuit. A limiting resistor, a lamp to be lit at night connected in series to the above power supply, and the lighting of this lamp. A series circuit with a lamp switch that controls turning off the light, and a diode that is connected in a forward direction between the switching circuit and the lamp that is turned on at night and short-circuits the resistor when the lamp is turned off. and is configured to dim the lighting of the pilot lamp when the lamp that is lit at night is turned on, and to detect whether or not there is a break in the lamp that is lit at night when the pilot lamp is self-checked. This will be described in detail below using examples.

FIG. 1 is a circuit diagram showing an embodiment of a warning display device according to the present invention, and shows an example of displaying the amount of light emitted from a pilot lamp in two levels.

In the same figure, a stop lamp LS and a tail lamp LT are connected to a power line supplied via an ignition switch SWIG, respectively, to a stop lamp switch (hereinafter referred to as
tail lamp switch (abbreviated as stop switch)
(hereinafter abbreviated as tail switch) SWT, and by closing these stop switches SWS and tail switch SWT, the stop lamp LS
, and a tail lamp LT, respectively.

Next, a pilot lamp PL is provided between the power supply line and the collector of the transistor Tr1, and the emitter of the transistor Tr1 is grounded via a resistor R1.
Further, it is connected to the tail lamp LT via a forward diode D1, and the current flowing through the pilot lamp PL is changed depending on whether the tail lamp LT is turned on or off, that is, whether the tail switch SWT is turned on or off.

That is, while the tail lamp LT is on, the diode D1
is in a cut-off state, and the current of the pilot lamp PL has a dimming amount determined by the resistor R1.

Next, the transistor Tr1 is turned on and off by the base current supplied from the collector of the transistor Tr2 via the resistor R2, and the base voltage of the transistor Tr2 is set by the voltage division of the resistors R3 and R4, and the emitter The voltage is set by dividing the resistors R5 and R6, and one end of the resistor R6 is grounded via the stop lamp LS.

Further, the emitter is grounded via a time constant capacitor C1.

On the other hand, voltage is supplied to the other ends of the resistors R3 and R5 from the power supply line via the pilot lamp PL and the resistor R7.

Furthermore, one end of the pilot lamp PL is also connected to an oil level switch SWO whose one end is grounded via a resistor R8, so that the pilot lamp PL can be turned on when the oil level decreases.

2 In addition, for the voltage division ratio of resistors R3 and R4, resistors R5,
R6 is set to cut off the transistor Tr2 when the stop switch SWS is open.

Next, the operation of the embodiment shown in FIG. 1 will be explained.

First, during daytime driving, the tail switch SWT is in an open state and the tail lamp LT is off.

As a result, the emitter of the transistor Tr1 is grounded through the diode D1.

In this state, when the stop switch SWS is pressed, the stop lamp LS is turned on and the resistor R6 is turned on.
The emitter potential of transistor Tr2 rises through this.

Therefore, the transistor Tr2 is turned on and drives the transistor Tr1 to be turned on.

At this time, the current flowing through the pilot lamp PL flows through the transistor Tr1, the diode D1, and the tail lamp LT, and the pilot lamp PL lights up brightly.

Next, we will explain the case where the stop lamp LS is disconnected when the stop switch SWS is not pressed.
Since one end of resistor R6 is open, transistor Tr2
turns on, turning on the transistor Tr1.

At this time, the pilot lamp PL lights up, but due to the voltage drop caused by this pilot lamp PL, the transistor T
Current cannot be supplied to r2.

As a result, the transistor Tr1 is turned off and the pilot lamp PL is turned off.

In other words, the pilot lamp PL repeatedly turns on and off (blinks), but the period is determined by the resistors R5 and R to the capacitor C1.
It is determined by the time constant of charging by 7 and discharging by the emitter input resistance of transistor Tr1.

Note that the pilot lamp PL at this time also blinks brightly.

Also, if the tail switch SWT is off during the day and the tail lamp LT is disconnected, the current flowing to the pilot lamp PL is limited by the resistor R1 and the pilot lamp PL lights up dimly, so when the stop switch SWS is on and the pilot lamp PL self-checks. Tail lamp LT
It is also possible to detect the presence or absence of wire breakage.

Next, when driving at night, the tail switch SWT is in a closed state, the tail lamp LT is lit, and the voltage across the tail lamp LT matches the voltage of the power supply line.

As a result, diode D1 is in a cut-off state,
The emitter of the transistor Tr1 is grounded through the resistor R1.

In this state, if the stop switch SWS is pressed, the pilot lamp PL will also light up, but
The current flowing at this time is limited by the resistor R1, and the light is dimly lit.

Next, if the stop lamp LS is disconnected while the stop switch SWS is not pressed, the pilot lamp PL blinks as in the daytime, but it blinks darkly due to the action of the resistor R1.

Therefore, with such a configuration, the pilot lamp PL
The emitter of the transistor Tr1, which controls turning on and off, is grounded via a resistor R1 and also connected to the tail lamp LT via a reverse current blocking diode D1. The lamp can be brightly lit and blinking, and at night the pilot lamp can be dimly lit and blinked to provide a suitable brightness for warnings and to indicate the presence or absence of a malfunction.

If the driver erroneously turns on the tail lamp LT during daytime driving, the pilot lamp turns on dimly and blinks, thereby giving a warning that the driver erroneously turns on the tail lamp LT.

Furthermore, when the oil level switch SWO is closed, the pilot lamp PL can remain lit to display a warning.

Next, FIG. 2 is a circuit diagram showing another embodiment of the warning display device according to the present invention, and this figure shows that when the stop lamp is disconnected in the circuit of FIG. It is equipped with a circuit that makes it blink.

In Fig. 2, the same reference numerals as in Fig. 1 indicate corresponding parts, and from the connection point of the pilot lamp PL and the transistor Tr1, only the alternating current is led to the rectifying diode D2 through the capacitor C2. A transistor Tr3, which charges a capacitor C3 with a rectified current and is connected in a composite manner through a resistor R9,
A base current is supplied to Tr4.

The collectors of the transistors Tr3 and Tr4 are connected to the emitter of the transistor Tr1, and the emitter of the transistor Tr1 is grounded when the transistors Tr3 and Tr4 are on.

Note that the cathode side of the diode D2 is also connected to the stop lamp LS via a forward diode D3.

Next, to explain the operation of the embodiment shown in FIG. 2, when the stop lamp LS is disconnected, the pilot lamp P
Since L blinks, capacitor C3 is charged through capacitor C2 and diode D2.

At the same time, the transistors Tr3 and Tr4 are turned on and the emitter of the transistor Tr1 is grounded.

As a result, regardless of whether the tail lamp LT is on or off, the emitter of the transistor Tr1 is grounded, so the pilot lamp PL is connected to the stop lamp L regardless of whether it is day or night.
Blinks brightly due to disconnection of S.

Note that the diode D3 causes the pilot lamp PL to blink when the stop switch SWS is intermittently opened and closed.
This function equivalently prevents the stop lamp LS from becoming disconnected and turning on the transistors Tr3 and Tr4. When the stop switch SWS is opened, it operates to discharge the charge in the capacitor C3 through the stop lamp LS. do.

Therefore, with such a configuration, the alternating current obtained from the pilot lamp PL due to the breakage of the stop lamp LS is rectified to charge the capacitor C3, and the emitter of the transistor Tr1 controls the pilot lamp PL on and off with the charging current. Since it is grounded, the stop lamp LS
When the wire is disconnected, a bright flashing warning can be displayed regardless of day or night.

Also, when the stop lamp is normal, it lights up brightly during the day.
As in the case of Fig. 1, the lamp can be turned on darkly at night.

Furthermore, as in the case of FIG. 1, when the tail lamp LT is turned on and off in the opposite manner, a warning can be given by the brightness and darkness of the pilot lamp PL.

In addition, in the present embodiment shown in FIG. 1, the warning display by the pilot lamp PL is displayed by lighting and blinking to indicate when the stop switch SWS is pressed and when the stop lamp is disconnected. The present invention is not limited to this. For example, by configuring as shown in FIG. 3, it is also possible to display a warning by lighting both of them.

Furthermore, in this embodiment, a case has been shown in which the brightness of the pilot lamp PL is determined by the voltage across both ends caused by the lighting of the tail lamp, but any lamp that is turned on at night, such as a headlamp, may be used instead of the tail lamp LT.

Further, although this embodiment shows a case where control is performed using a transistor, it is also possible to use other switching elements such as relays.

Further, in this embodiment, a modified multivibrator is used to turn on and off a transistor for controlling a pilot lamp, but it goes without saying that other oscillators with control terminals may be used.

As described above, according to the warning display device of the present invention, the brightness of the pilot lamp for warning and checking can be adjusted depending on the day and night, and when the checking circuit is abnormal, the brightness can be adjusted day or night. In addition, if the lamp that lights up at night is broken during the day, the pilot lamp will turn on dimly, so during the self-check of the pilot lamp, the presence or absence of a break in the lamp that lights up at night can also be detected. It has excellent effects such as being able to perform various functions, and is extremely effective for safe driving of a car and for simplifying the checking function of each part.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of a warning display device according to the present invention, and FIGS. 2 and 3 are circuit diagrams showing other embodiments of the present invention. Sw1G・・・Ignition switch, SW
T...Tail lamp switch, SWS...
... Stop lamp switch, SWO ... Oil level switch, LS ... Stop lamp, LT ... Tail lamp, Tr1, Tr2, T
r3, Tr4...Transistor, D1~D3・
...Diode, C1-C3...Capacitor, R1-R8...Resistance, PL...
pilot lamp.

Claims (1)

[Claims] 1. A disconnection detection unit that detects disconnection of the stop lamp by inputting the potential at the connection point between the stop lamp connected in series to the power supply and the stop lamp switch that controls turning on and off of the stop lamp, and a disconnection detection unit that detects disconnection of the stop lamp. a switching circuit that controls the pilot lamp by the output of the section, a resistor that limits the current of this switching circuit, a lamp that is connected in series to the power source that is lit at night, and a lamp that controls turning on and off of this lamp. a series circuit with a lamp switch; and a diode that is connected in a forward direction between the switching circuit and the lamp that is turned on at night and short-circuits the resistor when the lamp is off, When the lamp to be lit at night is turned on, the lighting of the pilot lamp is dimmed, and the presence or absence of a break in the lamp to be lit at night is detected during a self-check of the pilot lamp. A warning display device featuring: