JPS584347Y2 - Output circuit of transformerless equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an output circuit for transformer-less equipment that uses a capacitor to drop the power supply voltage, and in which an output element such as an output relay is directly driven by the power supply voltage.

In conventional transformerless equipment, its output circuit was constructed as shown in FIG.

The conventional example circuit shown in FIG. 1 has a time limit circuit as an electronic circuit block 2, which constitutes an electronic timer, and the power supply input terminals 6 and 7 are connected to one of them through a capacitor 1 in series, and a main circuit consisting of a diode bridge is connected to the power supply input terminals 6 and 7. It was connected to the input end of the rectifier circuit 8, and the output voltage of the main rectifier circuit 8 was smoothed by a smoothing capacitor 11 to drive the electronic circuit block 2.

In addition, in the conventional example shown in FIG.
The cathode side of the switch element 3 of this series circuit is connected to the output terminal negative side of the main rectifier circuit 8, and the other end of the output relay 4 is connected to the power supply input terminal 6, and the gate of the switch element 3,
An output signal from the electronic circuit block 2 was applied to the base of a transistor 9 whose collector and emitter were respectively connected to the cathode.

However, in the conventional circuit shown in FIG.
The input voltage 1 of the main rectifier circuit 8 has a phase lead of about 90 degrees with respect to the power supply voltage VAC applied to the main rectifier circuit 7. Therefore, the time limit circuit that constitutes the electronic circuit block 2 times up, and at that time, the output signal causes the transistor 9 is turned off and the switch element 3 is turned on, a part of the discharge current of the voltage drop capacitor 1 is transferred to the output relay 4 and the switch element 3, which have a higher impedance than the internal circuit including the electronic circuit block 2. The energy of the capacitor 1 flows through the circuit of the diode D1, which forms a part of the main rectifier circuit 8, through the path shown by the chain line in FIG. 1 during the time period T1 in FIG. 8 to the electronic circuit block 2, and the output voltage V of the main rectifier circuit 8
There was a problem in that the voltage level 2 drops lower than during the off period of the switch element 3, which adversely affects the electronic circuit block.

The present invention has been proposed in view of the above points, and is a transformer that prevents fluctuations in the voltage applied to the electronic circuit block due to turning on and off of the switching elements constituting the output circuit section and provides stable operation. The purpose is to provide an output circuit for wireless equipment.

The present invention will be explained in detail below with reference to embodiment figures.

FIG. 3 shows a circuit diagram of an embodiment of the present invention, in which the power input terminal 6,
7 is a rectifying diode 5 and an output relay 4 is an output element.
and a switch element 3 made of SCR are connected, and a resistor is connected in parallel to the output relay 4 and the anode and gate of the switch element 3, and the collector and emitter of a transistor 9 are connected to the gate and cathode of this switch element 3. An output circuit is constructed by connecting them to each other, and the output end of the electronic circuit block 2 is connected to the base of the transistor 9 via a diode 10 in series in the forward direction.

However, the electronic circuit block 2 is configured to short-circuit its output terminal to ground during output operation, turn off the transistor 9, and apply a gate signal to the switch element 3. A diode D2, which constitutes a part of the main rectifier circuit 8, is inserted and connected in series between the emitter and the negative pole of the electronic circuit block 1, and the voltage drop across this diode D2 ensures that the transistor 9 Since this may have an adverse effect on the transistor being turned off, a diode 1 is inserted and connected in series to the base of the transistor 9 as shown in the schematic diagram of FIG.
The voltage drop in the diode D2 is compensated for by the forward voltage drop of 0.

5 and 6 show another embodiment of the present invention, in which a light emitting diode 12 is inserted and connected in series between the output terminal of the main rectifier circuit 8 and the smoothing capacitor 11.
When a surge voltage is applied to the power supply, all of the rush current of the smoothing capacitor at this time flows to the light emitting diode 12,
In addition to the risk of destroying the light emitting diode 12, the lighting duration of the light emitting diode 12 varies due to fluctuations in the power supply voltage and other factors. This is an insertion connection.

However, in the embodiment of FIG. 5, the smoothing capacitor 1
Although the light emitting diode 12 is inserted and connected in the middle of the current supply path from 1 to the electronic circuit block 2, the inrush current of the smoothing capacitor 11 does not flow through the light emitting diode 12, and a surge voltage is generated in the power supply. This light emitting diode will not be destroyed even in the case where the light emitting diode is superimposed on the light emitting diode.

Furthermore, in the embodiment shown in FIG. 6, the smoothing capacitor 1
The voltage of Zener diode D2 is made safe by the Zener diode D2, and the light emitting diode 12 is inserted and connected further to the electronic circuit block 1 side than the Zener diode D7. The voltage across both ends is made constant, and therefore the current supplied from the Zener diode D2 to the electronic circuit block 2 is substantially chemotonic, and the light emitting diode 1
The brightness of the light emitted by the light emitting device No. 2 can be made substantially constant.

As mentioned above, the present invention connects a series circuit of an output element such as an output relay and a switch element to a power input terminal through a rectifying element such as a diode, and connects this power input terminal through a capacitor in series. Connect to the main rectifier circuit,
A diode is connected in forward series to the base of a transistor that supplies the output of this main rectifier circuit to the above electronic circuit block and provides a gate signal to the switch element, and the output of the electronic circuit block is connected to the base of the above transistor via this diode. However, when the switch element is turned on, part of the discharge current of the step-down capacitor no longer flows through this switch element, and therefore, the difference between when the switch element is on and when it is off is eliminated. This has the advantage that fluctuations in the main rectifier circuit output voltage do not occur, and the electronic circuit block can operate stably.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of the conventional example, Fig. 2 is a waveform diagram explaining the operation of the same as above, Fig. 3 is a circuit diagram of an embodiment of the present invention, Fig. 4 is a main part circuit diagram showing the operating state of the same as above, Fig. 5 6 are circuit diagrams of different embodiments of the present invention, where 1 is a capacitor and 2 is a circuit diagram of a different embodiment of the present invention.
is an electronic circuit block, 3 is a switch element, 4 is an output relay, 5 is a diode, 6 and 7 are power input terminals, 8 is a main rectifier circuit, 9 is a transistor, 10 is a diode, 11 is a smoothing capacitor, and 12 is a light emitting device. It is a diode.

Claims (1)

[Claims for Utility Model Registration] 1. The step-down voltage is rectified through a series capacitor and supplied to an electronic circuit block, and the output of this electronic circuit block turns on a switch element to output an output element such as an output signal. In the output circuit of a transformerless device that is driven, a series circuit of an output element such as the output relay described above and a switch element is connected to a power input terminal via a rectifying element such as a diode, and this power input terminal is A capacitor is connected in series to the main rectifier circuit, the output of this main rectifier circuit is supplied to the above electronic circuit block, and a diode is connected in forward series to the base of a transistor that provides a gate signal to the switch element. An output circuit for an I-lanceless device, which inputs an electronic circuit block output to the base of the transistor through the output circuit. 2. In the output circuit of the transformerless device described in claim 1 of the utility model registration claim, a smoothing capacitor is connected in parallel to the rectified output terminal of the main rectifier circuit, and the voltage across the smoothing capacitor is connected in series with a light emitting diode. The voltage is applied to the electronic circuit block.