JPS5826606B2 - automatic flasher - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an automatic flasher, and its purpose is to:
To provide a power-saving automatic flasher using a self-holding relay as an output relay, consuming power only at the moment when a contact is reversed, and consuming almost no power at other times.

Conventional automatic flashers use electric current to flow through a resistive heating element and use the heat to bend the bimetallic contacts, thereby maintaining the operating state of the contacts that open and close the load.Electromagnetic relays are used to maintain the operating state of the contacts. There is something that makes me

All of these automatic flashers require a continuous current to flow in order to maintain operation.

The present invention has been made as a countermeasure against the above problems, and aims to provide an automatic flasher with low power consumption. A Schmitt circuit consisting of a transistor T1.T and resistors R1 to R0, which receives the element CdS as an input, and a transistor T1.T of the Schmitt circuit. A self-holding relay X, a Schmitt circuit transistor T1, is connected between the collectors of T2 through mutually opposite diodes D1 and D2.
．． Self-holding relay X that conducts separately depending on the operation of T2
The driving transistor T3. T4 is provided, and at the switching contact X of the self-holding relay X, the driving transistor T3. This automatic flasher is characterized in that it is configured such that T4 is non-conductive.

Next, to describe the operation of the present invention, when transitioning from day to night, the light receiving element CdS, which is in a low resistance state during the day, has the base of the transistor T1 at the same potential as the e pole of the t source B, and the transistor T1 is non-conductive. T2 is in a conducting state.

When the surroundings become dark in the evening, the resistance value of the light receiving element CdS rises, and when it exceeds a certain level, the transistor T1.
T2 suddenly reverses, transistor T1 turns on,
Transistor T2 is turned off.

The conduction of the transistor T1 causes a base current to flow through the relay driving transistor T3, thereby causing conduction between the collector and emitter of the transistor T3.

Therefore, the self-holding relay X is driven by the current ■T3, and the switching contact to prevent

The self-holding relay X maintains the switching state of the switching contact X even if the current ■T3 disappears.

In the above operation, the current T3 is a short time after the transistor T1 conducts and the switching contact X of the self-holding relay X completes reversal. Since the transistor T2 is non-conductive in this state, no current flows through the other driving transistor T4.

Next, when night shifts to morning, the surroundings become brighter and the resistance value of the light receiving element CdS decreases, and when it becomes smaller than a certain value, the transistor T1 becomes non-conductive and the transistor T2 becomes conductive.

Therefore, the base current of the drive transistor T4 flows, and the electric current T4 flows to the self-holding relay X in the opposite direction to T3, and the self-holding relay
Switch it to the side.

For this reason, the base of the driving transistor T4 is short-circuited between the base and the terminal, making it non-conductive, and the current T4 disappears.

Here, the diode D3 connected between the collector of the transistor T1 and the collector resistor R3 prevents the current from the resistor R7 connected to the base circuit of the driving transistor T3 from flowing to the base resistor R4 of the transistor T2 of the Schmitt circuit. This is to prevent.

As described above, according to the automatic flasher of the present invention, the current flowing through the self-holding relay Since it only takes a short time of 20 m5 or less for the switching contact X to complete its reversal and for the drive transistor T3t or T4 to become non-conductive after the current has flowed, the effect of saving power consumption is large.

[Brief explanation of drawings]

The figure is an electrical circuit diagram showing an embodiment of the automatic flasher of the present invention. CdS... Light receiving element, T1. T2...
Transistor, R1 to R2... Resistor, T3.
T4...Transistor for bending section movement, X...Self-holding relay, X...Switching contact, Dl, D2.
D3...Diode.

Claims (1)

[Claims] 1. A Schmitt circuit that uses a photodetector as an input, a self-holding relay that connects the collector terminals of the transistors in the Schmitt circuit through diodes in opposite directions, and a self-holding type that conducts separately depending on the operation of the transistors in the Schmitt circuit. An automatic flasher characterized in that a relay driving transistor is provided, and a switching contact of a self-holding type relay is configured to make the driving transistor non-conductive after the relay is operated.