KR810001099Y1 - Voltage auto-exchange switching circuit - Google Patents

Abstract

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Description

Automatic voltage switching switch circuit

The accompanying drawings are automatic voltage switching switch circuit diagram of the present invention.

The present invention relates to a voltage switching switch attached to 100v / 220v combined electric and electronic equipment.

In the past, when a user uses a device with a voltage change switch, it is necessary to check whether the switch is switched to match the power supply voltage. There was even a risk of burning out.

The present invention has been made in view of the above-described drawbacks, and the user simply connects the device to a power source, so that the circuit is automatically switched in the device according to the power supply voltage. That is, when the voltage is automatically 100V according to the power supply voltage, the power is switched to be applied to the 100V tap of the transformer primary winding built in the device, when the voltage is 220V is switched to be applied to the 200V tap, Regardless of the change in the supply voltage, the secondary output voltage is maintained to be constant, which will be described in detail with reference to the accompanying drawings.

Referring to the accompanying drawings, the automatic voltage switching switch circuit of the present invention is configured between the plug (1) and the 100V / 220V combined transformer (T ₁ ), the first line (g) is a common line transformer (T ₁ ) Connected to the common tap (d) on the primary side, and the second line (h) is connected to the central tap (e) of the transformer (T ₁ ) via the fuse (fuse1) and the 100V pass-through circuit (4) depending on the applied voltage. Or via the fuse 2 and the 220V pass circuit 6 to the upper terminal f of the transformer T ₁ .

The first triac circuit 4 is composed of triacs. The triacs (R) and the capacitors (C) connected in series with the triac (triac1) are inductive loads. The parallel connection between the cathode (T ₁ ) and the anode (T ₂ ) of the triac1) to prevent the malfunction of the triac (triac1). In addition, a trigger circuit 3 for 100V was configured to control the current between the gate G and the cathode T ₁ of the triac triac. That is, in order to provide the gate current and the bias voltages of the first and second trigger circuits 3 and 5, the auxiliary transformer T ₂ is connected between the lines g and h, and the terminal of the secondary side of the transformer is connected. A diode D ₁ and a capacitor C ₁ were connected between the rectifier circuit 2. Accordingly, when 100 V is applied, the current at point a of the rectifier circuit 2 flows from the resistor R _{1 to the} diode D _{3 to} the base of the transistor TR ₁ , to the emitter to the common terminal b. The current at point a is the fuse (fuse1) → the cathode (T ₁ ) of the triac (triac1), the gate (G) → the resistor (R ₅ ) → the collector of the transistor (TR ₁ ), the emitter → the common terminal. (d), the triac triac1 of the first triac circuit 4 is energized. Accordingly, the supply voltage 100V is applied to the center tap e of the transformer T ₁ . Here, the resistor R ₁ of the first trigger circuit 3 is set not to exceed the maximum current of the base of the transistor TR ₁ , and the resistor R ₅ does not fail the gate trigger of the triac 1. It set to the value which limits a gate current in the range. In addition, the capacitor C ₂ is configured between the base of the transistor TR ₁ and the common terminal b so that the transistor TR ₁ is delayed for a predetermined time when the switch SW ₁ is turned on. .

The second triac circuit 6, which is operated when a voltage of 220 V is supplied to the device, is also composed of a triac2, a resistor R, and a capacitor C, similarly to the first triac circuit 4. The bias voltage of the 220V trigger circuit 5 that controls this triac2 is supplied at point a of the rectifier circuit 2 described above. That is, as the zener diode D ₂ of the second trigger circuit 5 is configured such that its cathode is connected to point a and its anode is connected to point C, the rectified voltage corresponding to the voltage of 220V supplied to the device. (I.e., voltage at point a, for example 22 VDC), the control diode D ₂ conducts, so that the voltage drop across resistor R ₂ connected between point C and common terminal b The current at point a flows through the zener diode (D ₂ ) → resistor (R ₃ ) → base of transistor (TR ₂ ) and emitter → common terminal (b), so that transistor (TR ₂ ) is energized. Accordingly, the transistor TR ₁ is in a non-conducting state, and the current at the point C flows through the resistor R _{4 to} the base of the transistor TR ₃ , and the emitter to the common terminal b. Accordingly, the transistor TR ₃ maintains the conduction state, and the current at the point a causes the fuse (fuse2) to the cathode (T ₁ ) of the triac (triac2), the gate (G) to the resistor (R ₆ ) → Since the collector of the transistor TR ₃ flows from the emitter to the common terminal b, the applied voltage of 220V is supplied to the 220V tap f of the transformer T ₁ via the triac2.

The 220V reference voltage detection diode D ₂ in the above circuit configuration does not conduct the threshold voltage of this zener diode D ₂ even when 120V voltage is supplied from the power supply (that is, a point voltage x 1.2 at 100V). Set. That is, since the voltage at point a of the rectifier circuit 2 is the voltage set by the primary and secondary winding ratios of the transformer T ₂ , if the voltage at point a is 10VDC when the power supply voltage is 100V, when the power supply voltage is 220V, The voltage at the point is 22 VDC. By the voltage of this difference, the zener diode D ₂ does not operate when 100 V is applied, but operates when 200 V is applied, and the corresponding trigger circuit is operated according to the voltage, so that each triac acts. In addition, when V _CE (SAT) of the transistor TR ₂ of the second trigger circuit is about 0.1 V, the transistor TR1 is completely non-conductive, but the base current of the transistor TR2 is short or V _CE (SAT) is 0.6. If it is V or more, the transistor TR ₁ may be conductive. However, this is eliminated by the configuration of the malfunction preventing diode D ₃ of the transistor TR ₁ in the circuit of the present invention. That is, since the diode D ₃ is a silicon diode, the transistor TR ₁ remains completely non-conductive when the transistor TR ₂ conducts due to its energizing voltage of 0.6V.

In the automatic voltage switching switch circuit of the present invention, when the power supply voltage reaches 120V and reaches about 130V, the resistance value of the resistor R ₃ is set so that a current flows to the base of the transistor TR ₂ by the C point voltage. In addition, the resistance value of the resistor R ₄ was selected to adjust the base voltage of the transistor TR ₃ so that the gate current of the triac 2 flows sufficiently when a power supply voltage of 180 V or more is supplied. Therefore, if the triac 1 operates at 120V or more and 130V and all the devices operate at 100V from 130V or more and less than 180V, there is a risk of overvoltage, and even if it is operated at 220V, a risk of reduced voltage may occur. Because of the danger, it is impossible to operate in any state, and the triac2 becomes conductive when a power supply voltage of 180V or more is supplied. Furthermore, since the automatic voltage switching switch of the present invention deals with an alternating current signal, at a potential that is gradually changed from 100 V to 220 V and the transistor TR ₁ cannot operate, the triac1 is applied to an alternating voltage of the power supply voltage. There is no problem by entering into a non-conducting state by itself. In addition, since the power source supplied to each trigger circuit 3 and 5 cannot form a zero potential because the rectified voltage is charged in the capacitor C ₁ , the transistors TR ₁ , TR ₂ , and TR ₃ have a power supply voltage. the itgekkeum the triac (triac1) by except that is not supplied to the transistor (TR _1), the triac (triac2) by a transistor (TR ₃₎ to be conductive at all times in the prepared state.

When the automatic voltage switch circuitry of the subject innovation, a capacitor (C ₂₎ consisting of a trigger circuit (2) for 100V is 220V supplied to connect the power switch (SW _1), the transistor (TR2) by the AC voltage to the first rising the conduction and thus it has the properties of preventing operation for the transistor (TR ₁₎ is the base voltage of the transistor (TR _1), to prevent conductive predetermined time (R ₁ × C _2), automatic voltage switching of the subject innovation The switch circuit can always perform stable operation. In addition, when the power switch SW ₁ is turned "off", the voltage at point a drops so that the diode D ₂ is not conducting, the transistors TR ₂ and TR ₃ are not conducting, and the transistor TR ₁ is conducting. Even when the gate current of Triac1 flows, neither the triac triac tria triac 2 nor the triac triac triac2 is operated, and thus no operational problem occurs.

As described above, the power supply voltage switching switch of the present invention is automatically switched without requiring the user's confirmation according to the applied voltage, and thus can be conveniently used in various electrical and electronic devices.

Claims (1)

As shown in the figure, when the voltage applied to the plug 1 is low and low voltage, 1 of the transformer T ₁ is passed through the rectifier 2, the first trigger circuit 3, and the first triac circuit 4. It is connected to the middle side tap (e) of the vehicle side, and when the high voltage is applied to the terminal tap (f) of the transformer (T ₁ ) through the rectifier (2), the second trigger circuit (5), and the second triac circuit (6). And a Zener diode (D ₂ ) and a transistor (R ₂ ) in the second trigger circuit (5) so as to be connected.