JPH06115399A - Flashing device of direction indicator - Google Patents

Abstract

PURPOSE:To provide a compact and less expensive flashing device of a direction indicator. CONSTITUTION:While an ON actuation signal 14a is generated from a switching control circuit 14, a switching element 11 comes to be in the state of conducting, and its both end voltage is low. Consequently, a condenser 12 for electric power source discharges and feeds to each of the control circuits 14. 15. In the meantime. during this time, as the switching control circuit 15 works and generates an OFF actuation signal 15a of a short cycle in precedence of the ON actuation signal 14a, the switching element 11 accordingly comes to be in the state of non-conducting in a short cycle, its both end voltage rises and the condenser 12 for electric power source is charged. As the condenser 12 for electric power source can be charged in a short cycle, it is possible to maintain electric power source voltage necessary for circuit actuation even with a condenser of small capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flashing device for a turn signal lamp, and more particularly to a flashing device in which a built-in power supply capacitor is downsized.

[0002]

2. Description of the Related Art As a simple flashing device (flasher) for flashing a turn signal lamp of a vehicle, for example, Japanese Patent Laid-Open No. Sho 64-9 is known.
There is a two-terminal type shown in Japanese Patent Publication No. 0831, which has two external terminals respectively connected to a battery and a turn signal lamp, and a supply current to the turn signal lamp is input between these two terminals. With a switching element to cut off,
Similarly, a power supply capacitor is connected between the two terminals through a discharge prevention diode, and power is supplied from the capacitor to the control circuit of the switching element. This allows a minimum of two external terminals, making the device relatively compact.

[0003]

By the way, in the above-mentioned blinking device, the power supply capacitor is charged when the switching element is in the OFF state with the blinking direction indicator light being selectively connected, and the power supply capacitor is charged when the following switching element is in the ON state. The capacitor is discharged and power is supplied to the control circuit. Normally, in automobiles, the ON time of the switching element is 0.
It takes about 35 seconds, and in order to maintain the capacitor voltage above the operable voltage (8V) of the control circuit even during the discharge, the voltage at the initial charging (battery voltage) is 12.8V,
When the current consumption is fixed at 2 mA, the capacitance C of the capacitor needs to be about 146 μF from the following equation. For this reason, it is necessary to use a large-sized aluminum electrolytic capacitor, which has been a bottleneck in downsizing and cost reduction of the entire device. C = (0.35 * 2 * 10 < ^-3 >) / (12.8-8) = 145.8 ([mu] F)

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a blinking device for a direction indicator lamp which is further compact and inexpensive.

[0005]

The structure of the present invention will be described. The power supply lines 41, 4 leading to the turn signals 2R, 2L of the vehicle.
2 is a switching element 11 interposed between the switching element 11 for turning on and off a supply current, and a power supply capacitor 1 connected with a charging diode 13 interposed between both ends of the switching element 11.
2, a first switching control circuit 14 which is supplied with power from the power supply capacitor 12 to operate and issues an ON-OFF operation signal to the switching element 11 at a long cycle, and is supplied with power from the power supply capacitor 12 to operate. And a second switching control circuit 15 for issuing an OFF operation signal to the switching element 11 in a short cycle in preference to the ON operation signal while the ON operation signal is being issued from the first switching control circuit 14. is doing.

[0006]

In the above structure, the switching element 11 is in the conductive state while the first switching control circuit 14 outputs the ON operation signal, and the voltage across the switching element 11 is low.
Therefore, the power supply capacitor 12 is discharged to supply power to the control circuits 14 and 15. On the other hand, during this period, the second switching control circuit 15 operates and issues an OFF operation signal of a short cycle in priority to the ON operation signal, and accordingly, the switching element 11 becomes non-conductive in a short cycle, The voltage across both ends rises and the power supply capacitor 12 is charged.

[0007] Thus, the power supply capacitor 12 in a short cycle.
Is charged, the power supply voltage required for circuit operation is maintained even with a capacitor having a small capacity.

[0008]

First Embodiment In FIG. 1, a flasher 1 is provided with two external terminals 61 and 62, one terminal 61 is connected to a battery 5 by a power supply line 41, and the other terminal 62 is a turn switch by a power supply line 42. 3 is connected to the left and right direction indicator lights 2R and 2L.

A MOSFET switching transistor 11 is provided between the terminals 61 and 62 to turn on / off the supply current to the direction indicators 2R and 2L. Above terminal 6
A resistor 17A and a charging diode 1 are also provided between terminals 1 and 62.
A power supply capacitor 12 is connected via 3. A resistor 17 is provided at the connection point between the diode 13 and the capacitor 12.
The Zener diode 18 is connected via B, and the oscillation circuit 16 is also connected.

The oscillator circuit 16 includes resistors 163, 164, 165 connected to the "+" terminal of the operational amplifier 161.
And a resistor 166 and a capacitor 162 connected to the “−” terminal thereof, the output of the operational amplifier becomes “1” level when the Zener voltage is supplied, and the resistor 163,
The capacitor 162 is charged through the resistor 166 to the divided voltage by the resistor 165 and the resistor 164. When the capacitor voltage exceeds the divided voltage, the operational amplifier output becomes "0" level, and the capacitor 162 is discharged through the resistor 166 to the divided voltage by the resistors 163, 164 and 165. By repeating this, the pulse signal 16a is emitted from the oscillation circuit 16 (op amp 161).

The switching control circuit 15 has a NOR gate 1 for inputting the output signals of a large number of flip-flops 151 connected in series and each of the flip-flops 151 except the initial stage.
52, it receives the pulse signal 16a and outputs the OFF operation signal 15a which becomes "0" level in a short period.

The switching control circuit 14 is composed of a large number of flip-flops 141 connected in series. The flip-flop output of the final stage of the switching control circuit 14 is input to the switching control circuit 14 for a long period of "1" level and "0" level. The ON-OFF operation signal 14a is repeated.

The signals 14a and 15a are supplied to the AND gate 1
9 and the transistor 11 becomes conductive when the output of the AND gate 19 is at "1" level. A Zener voltage is supplied to the circuit components of each of the circuits 14 and 15.

The operation of the flasher having the above structure will be described below with reference to FIG.

When either of the turn signals 2R and 2L is selected by the turn switch 3, the power source capacitor 12 is passed from the battery 5 via the resistor 17A and the charging diode 13.
Are rapidly charged, and the capacitor voltage V2 rises to the battery voltage + B. The Zener voltage Vz is supplied to the oscillator circuit 16 and the switching control circuits 14 and 15 to start their operation, and the output voltage V1 of the AND gate 19 repeats the "1" level and the "0" level in a long cycle T1, In response to this, the transistor 11 becomes conductive and non-conductive, and the direction indicators 2R and 2L blink.

While the output voltage V1 is at "1" level as a whole, the output voltage V1 becomes "0" level for a short period T3 for a short period T2 by the signal 15a, and the transistor 11 is non-conductive during this time T3. Then, the source-drain voltage rises, and the power supply capacitor 12 is charged. Thus, the power supply capacitor 12 is periodically charged to prevent the voltage V2 thereof from falling below the Zener voltage Vz. In FIG. 2, the line x shows the change of the capacitor voltage V2 when the periodic charging is not performed, and the line y shows the voltage change of the conventional large-capacity capacitor. In this case, for example, if the conduction duty of the transistor 11 is set to about 99% and the intermittent frequency is set to about 90 Hz, the lighting state of the direction indicator lights 2R and 2L is not affected.

According to the present invention, since the capacity of the power supply capacitor can be reduced, a small and inexpensive ceramic capacitor or the like can be used in place of the conventional large-sized aluminum electrolytic capacitor.

[0018]

Second Embodiment FIG. 3 shows another embodiment of the present invention, in which the switching transistor 11 is appropriately turned off so that the voltage of the power supply capacitor 12 falls within a certain range. In the figure, the oscillator circuit 16 also serves as the switching control circuit 14 of the above-mentioned embodiment, and its output signal 16a is directly input to the transistor 11 so that it has a long period T1 (FIG. 4).
To turn on and off.

The switching control circuit 15 has resistors 154 and 155 for dividing the Zener voltage Vz and resistors 156 and 157 for dividing the capacitor voltage V2, and these divided voltages are input to the input terminals of the comparator 153, respectively. There is. The comparator 153 has hysteresis due to an attached resistance and diode, and its output signal is input to the base of the transistor 158 connected to the gate of the transistor 11. The other structure is the same as that of the above-mentioned embodiment.

When the capacitor voltage V2 drops below VL (FIG. 4) during the conduction operation of the transistor 11, the output of the transistor 158 becomes "0" level by the output of the comparator, and the transistor 11 becomes non-conductive for a short time and the capacitor for the power supply. 12 is charged. When the capacitor voltage V2 is restored to VH (Fig. 4), the output of the comparator is inverted and the transistor 11 becomes conductive again. Thus, it is prevented that the capacitor 11 is charged by the non-conduction of the transistor 11 in a short period during the conduction operation, and the voltage V2 thereof becomes lower than the Zener voltage Vz.

Since the non-conducting operation of the transistor 11 is for a short time, it does not affect the lighting state of the direction indicator lamps 2R and 2L, and this embodiment has the same effect as the above embodiment.

In each of the above-mentioned embodiments, it is possible to add a disconnection detection circuit for the indicator lamp, a load short circuit protection circuit, and the like.

[0023]

As described above, according to the blinking device of the present invention, since a small-capacity power supply capacitor can be used, the device size can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a blinking device according to an embodiment of the present invention.

FIG. 2 is a signal time chart in one embodiment.

FIG. 3 is a circuit diagram of a blinking device according to another embodiment of the present invention.

FIG. 4 is a signal time chart in another embodiment.

[Explanation of symbols]

 1 Flasher (blinking device) 11 Switching transistor (switching element) 12 Power supply capacitor 13 Charging diode 14, 15 Switching control circuit 2R, 2L Direction indicator light

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tomihisa Ishikawa, 1-1, Showa-cho, Kariya city, Aichi prefecture, Nihon Denso Co., Ltd. (72) Inventor, Susumu Kuroyanagi, 1-1, Showa-cho, Kariya city, Aichi prefecture Sozo Co., Ltd.

Claims (1)

[Claims] 1. A switching element, which is provided in a power supply line to a turn signal lamp of a vehicle and turns on and off a supply current, and a power supply capacitor connected with a charging diode interposed between both ends of the switching element. , Is operated by being supplied with power from the power source capacitor, and the switching element is operated at a long cycle
A first switching control circuit which issues an N-OFF actuation signal and the power supply capacitor actuates to operate, and while the ON actuation signal is issued from the first switching control circuit, the ON actuation signal has priority. And then OFF in a short cycle
A blinking device for a turn signal lamp, comprising a second switching control circuit for issuing an operation signal to the switching element.