JPH022677Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an interior light delay extinguishing device for an automobile, and in particular, an easy-to-install interior light delay extinguishing device suitable for modifying the interior lights of a vehicle in use to delay extinguishing. Regarding.

In recent years, even when the door is closed, it has become a part of the car's equipment.
Some cars are equipped with so-called interior light delay extinguishing devices that keep the interior lights on for about 10 seconds. It's convenient.

However, the conventional interior light delay extinguishing device is very difficult to install on a used vehicle.

FIG. 1A shows a lighting circuit for a general interior light, which is composed of a power source battery 1, an interior light 2, and a door switch 3. FIG. 1B shows a conventional example of an indoor light delay extinguishing device, in which a delay circuit 16 is inserted in FIG. 1A.

To remodel from Figure 1A to Figure 1B, disconnect point A in Figure 1A, connect terminals B and C of the delay circuit in parallel to interior light 2, and connect door switch 3 to delay circuit 1.
It is necessary to change the wiring such as when connecting to the door switch terminal D of No. 6. This work would not pose a particular problem in the automobile production process, but for cars in use, it would be necessary to find the wiring related to the interior lights and change the wiring as described above, which would be impossible for an average amateur. .

Furthermore, in the conventional device, current flows through the delay circuit 16 even when the indoor light is off, which wastes energy.

This invention was made in view of the above drawbacks,
It is an object of the present invention to provide an interior light delay extinguishing device that can be easily attached to a vehicle in use and can perform a delayed extinguishing operation of interior lights.

According to the present invention, by simply connecting a delay circuit in parallel with the door switch 3, that is, between the ground and the door switch side of the interior light, the interior light can be turned off in a delayed manner. There is no need to cut it, so it is very easy to install.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention, in which a time constant circuit consisting of a series circuit of a resistor 5 and a capacitor 6 and a parallel circuit of a resistor 7 are connected between the base and emitter of an NPN type output transistor 4. A discharge circuit is formed, and the collector of a PNP charging transistor 9 is connected to the connection point between the resistor 5 and the capacitor 6 via a diode 8, and a resistor 10 is connected between the base and emitter of the charging transistor 9. The emitter is connected to the collector of the output transistor 4 to form a charging circuit for the capacitor 6, and further connected to the NPN type control transistor 12 via the base resistor 11 of the charging transistor 9.
The base of the control transistor 12 is connected to the collector of the output transistor 4 through a series circuit of a resistor 14 and a capacitor 13, and the emitter of the control transistor 12 is connected to the emitter of the output transistor 4. A delay circuit 16 is constructed by connecting a resistor 15 between the base and emitter of the circuit.

The collector and emitter of the output transistor 4 of the delay circuit 16 having the above configuration are connected in parallel to the door switch 3 to effect a delayed light-off operation.The operation will now be described.

When the door of the automobile is opened, a door switch 3 is closed, current flows from a power battery 1 to an interior light 2, and the interior light 2 is turned on. This is the same as normal lighting operation. At this time, the charge in the capacitor 13 is discharged through the resistor 14 and the door switch 3. When the door is closed, the door switch 3 is opened, so that no current flows to the interior lamp, and the point A, that is, the collector potential of the output transistor 4 rapidly rises to the potential of the power supply battery 1. Therefore, resistor 14, capacitor 1
The charging current of the capacitor 13 flows to the base of the control transistor 12 through the control transistor 3. The control transistor 12 is momentarily turned on and the collector potential drops, so the charging transistor 9 is also momentarily turned on and the capacitor 6 is connected through the diode 8 to almost the power supply battery voltage. After charging up to capacitor 6
The charge is transferred to the output transistor 4 via the resistor 5.
The output transistor 4 is turned on by the discharge current, the collector potential decreases, and a current flows to the indoor lamp 2. The charge in the capacitor 6 decreases with time. That is, as the base current of the output transistor 4 decreases, the collector potential gradually rises, and after a predetermined time, the output transistor 4
is finally turned off and the interior lights go out. In addition,
When the output transistor 4 turns ON, the charge in the capacitor 13 is discharged through the resistors 14 and 15, and is charged again when the output transistor 4 turns OFF. increases, so the charging current of the capacitor 13 at this time does not turn on the control transistor 12 and does not perform the so-called oscillation operation.

Also, the moment the door switch 3 is opened, the current flowing to the interior light is cut off, but after a very short time the output transistor 4 turns on and the current flows again, so you do not visually notice that the light has turned off. .

Figure 3 shows the collector voltage of output transistor 4.
It represents the temporal changes in V _CE , the base current I _B of the control transistor, and the voltage Vc ₆ of the capacitor 6.

As mentioned above, according to the present invention, by simply connecting a delay circuit in parallel with the door switch, the interior lights can be turned off in a delayed manner.
It eliminates the need to cut part of the wiring,
It is possible to provide an interior light delay extinguishing device that is extremely easy to install.

In addition, with this invention, when the indoor lights are turned off,
Since no current flows through the delay circuit, it is also effective in saving energy.

In the embodiment of the present invention, the resistor 14 may be omitted in some cases, and the control transistor 12 may be replaced with another switching element, such as a thyristor.

[Brief explanation of the drawing]

Figure 1A is a general circuit diagram of the interior light lighting circuit.
Figure B is a configuration diagram of the conventional indoor light delay extinguishing device,
The figure is a configuration diagram of an embodiment of the present invention, and FIG. 3 is a diagram illustrating the operation. 1... Power supply battery, 2... Interior light, 3... Door switch, 4... Output transistor, 5... Resistor,
6... Capacitor, 7... Resistor, 8... Diode, 9... Charging transistor, 10, 11...
...Resistor, 12...Control transistor, 13...Capacitor, 14, 15...Resistor, 16...Delay circuit.

Claims (1)

[Scope of utility model registration request] In an interior light delay extinguishing device that keeps the interior lights of a car on for a certain period of time even after the door is closed, the delay circuit consists of an NPN output transistor and a resistor connected to the base of the output transistor that determines the conduction time. a time constant circuit consisting of a first capacitor and a first capacitor, and a time constant circuit that controls charging of the first capacitor.
It consists of a PNP type charging transistor and a switching element that applies the collector voltage of the output transistor to a control terminal via a second capacitor to control the charging transistor, and connects the collector-emitter junction of the output transistor to a door switch. An interior light delay extinguishing device for an automobile, characterized in that the interior light is turned off in a delayed manner by being connected in parallel with the interior lights.