JPS6012054Y2 - door lock lighting circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an illumination circuit for a door lock, such as a door lock illumination circuit that can illuminate the keyhole of a cylinder lock provided on an automobile door.

Conventionally, in the case of a car, this type of lock is illuminated by a light bulb or light emitting light installed near the keyhole, which is activated by rotating a handle on the door to open and close the door, or by operating a switch button installed on the outside of the door. Since a lighting member such as a diode lights up and illuminates the keyhole, it is convenient to insert the key easily even at night or in a dark place.

By the way, the lighting members are turned on by turning the handle or pressing the switch button, and are turned on at the same time, so even if the handle or the switch button mechanism fails, the lighting may continue to turn on. There is a phenomenon that the battery is consumed due to this.

To solve this problem, some devices use a capacitor to turn on the light for a certain period of time and then turn it off automatically depending on the capacitor's charging capacity, but this type of circuit uses a transistor. Therefore, for example, when an abnormal reverse voltage generated from the coil due to the opening and closing of a motor or other relay that drives a wiper or power window used for something other than a keyhole lamp, that is, ■ is applied to the ○ side. This has the disadvantage that the keyhole cannot be illuminated because the transistor or light emitting diode LED is damaged.

The present invention was developed by focusing on such optical rotation, and its purpose is to prevent the application of abnormal reverse voltage generated from the coil by opening and closing of the motor or other relays, and to prevent damage. to avoid.

In order to achieve this purpose effectively and satisfactorily, the power supply
This is because a diode D is connected in parallel to the side.

That is, a diode D connected in parallel to the power supply ■ side and the ○ side, a capacitor C connected to the ■ side via a resistor, a switch S1 connected to the ○ side of this capacitor C, and this capacitor C. The resistor R2 connected between the ○ side and the switch S1 is connected to the base of the transistor Q, and one of the switch S2 and the resistor R3 is connected between this resistor R2 and the base, and the other is connected to the ■ side. connection,
This is provided by connecting the ■ side to the emitter of the transistor Q, and connecting the illumination member between the collector and the e side.

Further, the lighting member uses a light bulb, a light emitting diode, or the like.

An embodiment of the present invention will be described below with reference to an electric circuit diagram. A diode D is connected in parallel to the power source ■ side and e side, a capacitor C is connected to the ■ side via a resistor R□, and this capacitor C is A resistor R2 is connected between the switch S1 and the e side of the capacitor C, and a resistor R2 is connected to the base of the transistor Q, and a switch is connected between the resistor R2 and the base. S2
and resistor R3 are connected, the other is connected to the ■ side, the ■ side is connected to the emitter of the transistor Q, and a light emitting diode LED is connected between the collector and the O side.

Next, the operating state of the embodiment will be explained. First, the door handle (not shown) is pulled up or rotated to open the switch S1. S2 is configured to be closed, and when this switch S□ is closed, current flows from the ■ side through the resistor R1 → capacitor C → switch S1 to the e side, so that the capacitor C is charged at this time. is carried out.

At the same time, the current flows from the ■ side to the O side via the resistor R□→switch S2→resistance R2→switch S1.

At this time, since the base and emitter of transistor Q are short-circuited by switch S2, no base current flows, so transistor Q does not become conductive.

Next, at the same time as you let go of the handle that is still pulled up, switch S1. The capacitor C is opened in the order of S2.
The side is connected to the emitter of the transistor Q, and the ○ side is connected to its base, so that the transistor becomes conductive and a collector current flows to the collector.

Therefore, the light emitting diode LED in the collector circuit lights up.

In the present invention, as described above, the diode D is connected in parallel to the ■ side and the e side of the power supply, so that when a reverse voltage occurs, the transistor 01 light emitting diode D can be bypassed so as not to be damaged. It is something that you have.

[Brief explanation of drawings]

The accompanying drawings are electrical circuit diagrams showing one embodiment of the present invention. D...Diode, Sl, S2...Switch, C...Capacitor, Q...Transistor, LED...Light emitting diode, R1
, R2, R3...Resistance.

Claims (1)

[Scope of utility model registration request] A diode D is connected between the ■ side and the e side of the DC power supply, a capacitor C connected via a resistor R□, and a switch S1 connected to the e side of this capacitor are connected in parallel, and the capacitor C and switch S□ The connecting terminal of the capacitor C is connected to the base of the transistor Q via the resistor R2, the ■ side of the capacitor C is connected to the emitter of the transistor Q, and a switch S2 and a resistor R3 are connected in parallel between the emitter and base of the transistor Q. A lighting circuit for a door lock, wherein the collector of the transistor is connected to the e side of a power source via a light emitting diode LED.