TWI565363B - Switch device - Google Patents

Description

Switching device

The present invention relates to a switching device, and more particularly to a switching device for switching between a state in which electric power is supplied from an AC power source to a load and a state in which supply of electric power is interrupted.

Conventionally, an automatic switch having a heat ray sensor has been proposed, the heat ray sensor including a heat ray sensor for detecting heat rays radiated from a human body (for example, see Japan) Published Patent Publication No. 2005-183319 A, hereinafter referred to as Document 1). The automatic open relationship with the heat ray sensor is used to switch between an ON state and an OFF state of the fan load based on the output of the heat ray sensor.

The automatic switch having a heat ray sensor disclosed in Document 1 includes a latch relay including a contact inserted between a commercial power source and a fan load, and a signal processing unit. When the heat ray sensor detects the heat ray when the contact is in the off state, the signal processing unit switches the state of the contact from the off state to the on state by driving the current to the set coil of the relay. Start the fan load with the status.

An automatic open relationship with a heat ray sensor is used to supply an operating voltage to the signal processing unit by rectifying the voltage from the commercial power source with a rectifier and stabilizing the output of the rectifier in the power supply circuit unit. A parallel circuit of a capacitor and an electrolytic capacitor is connected between the output terminals of the rectifier via a diode. The output voltage of the rectifier is clamped to the sense voltage by the sense diode and smoothed by the electrolytic capacitor. The voltage across the electrolytic capacitor supplies the exciting current to the operating coil or reset coil.

Regarding the automatic switch with the heat ray sensor disclosed in Document 1, even when the relay is in the off state, if the output voltage of the rectifier becomes higher than the sense voltage, the Sin diode is turned on and the current is passed through Flowing in the second pole. At this time, a current having the same intensity as the current flowing through the action coil or the return coil flows through the arrester diode, so there is a problem that power is wasted (even when the fan load is not operating).

The present invention has been made in view of the above problems, and an object of the present invention is to provide a switching device capable of reducing standby power.

The switching device of the present invention comprises: at least one switching element inserted into an electrical path and electrically connected to the electrical path, the electrical path connecting an AC power source to a load; a driving circuit, the driving circuit Receiving power required to drive the at least one switching element from the AC power source, and selectively switching a contact state of the at least one switching element to a first state and a second state; and a switching circuit for changing a path through which a current is driven to cause current to be driven from the AC power source to the driving circuit through a first current path when the contact state is the first state, And when the contact state is the second state, the first current path is interrupted and a current is driven to flow from the AC power source to a second current path, the second current path having a lower impedance than the first current path High impedance.

According to the present invention, it is possible to provide a switching device capable of reducing standby power.

Hereinafter, the switching device of this embodiment will be described with reference to the drawings. The configurations described below are merely an example of the present invention. The present invention is not limited to the following embodiments, and various modifications may be made thereto without departing from the spirit and scope of the invention.

Fig. 1 is a circuit diagram of a switching device 1 of the present embodiment.

The switching device 1 of the present embodiment includes relays 10 and 11 (switching elements), a first driving circuit 20 (driving circuit), and a switching circuit 30. In addition to the above configuration, the switching device 1 of the present embodiment further includes a bidirectional thyristor 12, a signal processing unit 40, a second driving circuit 50, a surge absorbing circuit 60, a human sensor 70, and a power supply circuit 80.

The switching device 1 includes two input terminals 91 and 92 connected to an AC power source 200 (for example, a commercial AC power source), two load terminals 93 and 94 connected to the lighting load 300, and two load terminals 95 and 96 connected to the fan load 400. . The input terminal 92 is electrically connected to the load terminals 93 and 95 via internal wiring of the switching device 1. For example, the lighting load 300 includes an LED illuminator that includes a light emitting diode (LED) as a light source.

A contact 101 of the electromagnetic relay 10 as a switching element is connected between the input terminal 91 and the load terminal 94. The current limiting resistor R1 is connected between the load terminal 93 and the load terminal 94. In a state where the AC power source 200 is connected between the input terminals 91 and 92 and the illumination load 300 is connected between the load terminals 93 and 94, the AC power source 200 is connected to the contact 101 via a parallel circuit of the resistor R1 and the illumination load 300. Between the two ends.

A series circuit of the two-way thyristor 12 and the coil L1 is connected between the two ends of the contact 101. The bidirectional thyristor 512 on the output side of the photocoupler 51 is electrically connected between the terminal T2 of the bidirectional thyristor 12 and the gate terminal G1 via a resistor R2. A parallel circuit of the resistor R3 and the capacitor C1 is connected between the gate terminal G1 of the bidirectional thyristor 12 and the terminal T1.

A contact 111 of the electromagnetic relay 11 as a switching element is connected between the input terminal 91 and the load terminal 96. In a state where the AC power source 200 is connected between the input terminals 91 and 92 and the fan load 400 is connected between the load terminals 95 and 96, the series circuit of the AC power source 200 and the fan load 400 is electrically connected at the two ends of the contact 111. between.

The rectifier DB1 formed by the diode bridge is connected between the input terminal 91 and the input terminal 92 via a series circuit of a resistor R5 and a capacitor C3.

The switch circuit 30 is connected to the output side of the rectifier DB1. The switch circuit 30 includes a resistor R6, a Zener diode ZD1 and ZD2, and a transistor 31.

A series circuit of the resistor R6 and the Zener diode ZD1 is connected between the direct current (DC) output terminals DB11 and DB12 of the rectifier DB1. The cathode of the Zener diode ZD1 is connected to the resistor R6, and the anode of the Zener diode ZD1 is connected to the DC output terminal DB12 (the ground of the circuit) on the low potential side of the rectifier DB1.

The transistor 31 is an NPN transistor. The collector of the transistor 31 is connected to the DC output terminal DB11 on the high potential side of the rectifier DB1 via the sense diode ZD2. Here, the cathode of the Zener diode ZD2 is connected to the DC output terminal DB11 on the high potential side of the rectifier DB1, and the anode of the Zener diode ZD2 is connected to the collector of the transistor 31. The base of the transistor 31 is connected to the junction between the resistor R6 and the gate diode ZD1.

For example, the smoothing capacitor C4 formed by the electrolytic capacitor is connected between the emitter of the transistor 31 and the ground of the circuit. The emitter of the transistor 31 is electrically connected to the anode of the LED (Light Emitting Diode) 511 included in the photocoupler 51 via a resistor R7. The cathode of the LED 511 is connected to the ground of the circuit via a switching element 52, such as a transistor. The control terminal of the switching element 52 is connected to the output 埠P3 of the signal processing unit 40, and the switching element 52 is turned on or off according to the voltage level of the output 埠P3.

One end of the relay coil 102 included in the relay 10 is electrically connected to the emitter of the transistor 31. The other end of the relay coil 102 is connected to the ground of the circuit via a series circuit of a resistor R10 and a switching element 21 (for example, a transistor). The diode D1 is connected in parallel to the relay coil 102. The cathode of the diode D1 is connected to the emitter of the transistor 31, and the anode of the diode D1 is connected to the resistor R10. The diode D1 is arranged for the purpose of forming a path through which a current caused by a counter electromotive force occurring in the relay coil 102 flows when the current flowing through the relay coil 102 is interrupted. The control terminal of the switching element 21 is connected to the output 埠P1 of the signal processing unit 40, and the switching element 21 is turned on or off according to the voltage level of the output 埠P1.

One end of the relay coil 112 included in the relay 11 is electrically connected to the emitter of the transistor 31. The other end of the relay coil 112 is connected to the ground of the circuit via a series circuit of a resistor R11 and a switching element 22 (e.g., a transistor). The diode D2 is connected in parallel to the relay coil 112. The cathode of the diode D2 is connected to the emitter of the transistor 31, and the anode of the diode D2 is connected to the resistor R11. The diode D2 is arranged for the purpose of forming a path through which a current caused by a counter electromotive force occurring in the relay coil 112 flows when the current flowing through the relay coil 112 is interrupted. The control terminal of the switching element 22 is connected to the output 埠P2 of the signal processing unit 40, and the switching element 22 is turned on or off according to the voltage level of the output 埠P2.

Therefore, the first driving circuit 20 is formed by the current limiting resistors R10 and R11 and the switching elements 21 and 22. The first driving circuit 20 is configured to selectively switch the contact state of the relays 10 and 11 as switching elements to a first state (ON state) and a second state (OFF state). Any one of them.

For example, the signal processing unit 40 is a microcomputer and is used to achieve a desired function by executing a program stored in a memory in the microcomputer.

The surge absorbing circuit 60 is formed by a series circuit (RC series circuit) of a resistor R4 and a capacitor C2. The surge absorbing circuit 60 is connected between the AC power source 200 and the illumination load 300 in parallel with the bidirectional thyristor 12.

For example, the human sensor 70 includes a pyroelectric type infrared detecting element for detecting heat rays (infrared rays) radiated from the human body. The human sensor 70 detects whether a person exists in a detection area based on the detection result of the infrared detecting element. When the presence of a person is detected, the human sensor 70 outputs a detection signal to the signal processing unit 40.

The power circuit 80 is for reducing the AC voltage input from the AC power source 200, then converting the reduced AC voltage to a DC voltage of a desired voltage value, and supplying the operating voltage to an internal circuit (eg, the signal processing unit 40) .

The switching device 1 of the present embodiment has the above configuration, and the operation of the switching device 1 is described later.

First, the operation of the switching device 1 when there is no person in the detection area of the human sensor 70 will be described.

When there is no person in the detection area of the human sensor 70, the signal processing unit 40 does not receive the detection signal from the human sensor 70. The signal processing unit 40 performs the following operations to turn off the lighting load 300 and stop the fan load 400.

When the human sensor 70 does not input the detection signal, the signal processing unit 40 sets all the voltage levels of the outputs 埠P1, P2, and P3 to the low level, and turns off all of the switching elements 21, 22, and 52. In this case, current does not flow through the relay coils 102 and 112, and both of the contacts 101 and 111 are in a closed state. The current also does not flow through the LED 511, and the bidirectional thyristor 512 is in a closed state such that the bidirectional thyristor 12 is in a closed state. Therefore, when there is no person in the detection area of the human sensor 70, the lighting load 300 is turned off and the fan load 400 is stopped. When all of the switching elements 21, 22, and 52 are in the off state, the base current does not flow through the transistor 31 and the transistor 31 is in the off state. While the output voltage of the rectifier DB1 is higher than the arrest voltage of the Zener diode ZD1, current flows from the rectifier DB1 via the resistor R6 and the sense diode ZD1. Here, the second current path RT2 is formed by the resistor R6 and the sense diode ZD1, and drives the current from the AC power source 200 in the second state (in this state, the excitation current does not flow through the relay coils 102 and 112). )flow. The second current path RT2 is coupled to the resistor R6 to limit the current flowing through the second current path RT2.

Next, the operation of the switching device 1 when there is a person in the detection area of the human sensor 70 will be described.

When a person in the detection area of the human sensor 70 and the human sensor 70 input a detection signal to the signal processing unit 40, the signal processing unit 40 performs the following operations to turn on the illumination load 300 and cause the fan load 400 to perform ventilation. .

The signal processing unit 40 first switches the voltage levels of the outputs 埠P2 and P3 from a low level to a high level while maintaining the voltage level of the output 埠P1 at a low level. At this time, the switching element 21 is maintained in the off state, and the switching elements 22 and 52 are switched from the off state to the on state.

When the switching element 22 is turned on, the base current flows through the transistor 31 to switch the transistor 31 from the off state to the on state, and the capacitor C4 smoothes the ripple voltage input from the rectifier DB1. At this time, current flows from the capacitor C4 through the relay coil 112, the resistor R11, and the switching element 22 in order, so that the exciting current flows through the relay coil 112 to open the contact 111 of the relay 11. When the contact 111 is turned on, the AC power source 200 supplies AC current to the fan load 400 via the contact 111, and the fan load 400 rotates the motor to perform ventilation.

When the switching element 52 is turned on, current flows from the capacitor C4 through the resistor R7, the light emitting diode 511, and the switching element 52, and the bidirectional thyristor 512 is at the zero crossing point of the AC voltage input by the AC power source 200. Switch from off state to on state. When the two-way thyristor 512 is turned on, a voltage higher than a break over voltage is applied to the gate terminal (gate electrode) G1 of the bidirectional thyristor 12 and the bidirectional thyristor 12 is switched from the off state to the on state. . When the two-way thyristor 12 is turned on, AC power is supplied from the AC power source 200 to the lighting load 300 via the two-way thyristor 12 to turn on the lighting load 300.

Here, the lighting load 300 is a resistive load. Therefore, when the two-way thyristor 12 is turned on, a rush current flows from the AC power source 200 to the illumination load 300. When the lighting load 300 is turned on, the inrush current does not flow through the contact 101 of the relay 10, but through the bidirectional thyristor 12 as a semiconductor switch. In other words, when the lighting load 300 is turned on, an inrush current flows through the bidirectional thyristor 12 since the contact 101 is in the off state and the bidirectional thyristor 12 is turned on. Therefore, we can protect the contact 101. The fan load 400 is an inductive load, and the inrush current does not flow into the fan load 400 when the contact 111 is turned on. Therefore, the two-way thyristor is not connected in parallel to the contact 111, and the current carried to the fan load 400 is only turned on and off by the contact 111.

After a predetermined first delay period has elapsed from the time when the bidirectional thyristor 12 is switched from the off state to the on state, the signal processing unit 40 switches the voltage level of the output 埠P1 from the low level to the high level. At this time, the state of the switching element 21 is switched from the off state to the on state to cause the exciting current to flow through the relay coil 102, so that the contact 101 is turned on. After a predetermined second delay period elapses from the time when the state of the contact 101 is switched from the off state to the on state, the signal processing unit 40 switches the voltage level of the output 埠P3 from the high level to the low level. At this time, the state of the switching element 52 is switched from the on state to the off state to stop the flow of current through the LED 511, so that the bidirectional thyristor 512 is turned off. When the two-way thyristor 512 is turned off, the two-way thyristor 12 is turned off and current flows from the AC power source 200 to the lighting load 300 only via the contacts 101. The first delay period only needs to be set slightly longer than the period during which the inrush current flows when the illumination load 300 is turned on, for example, about one second. The second delay period only needs to be set slightly longer than the required operation period (the time from when the relay coil 102 carries the current to the time when the contact 101 is closed), and is set to an appropriate period in accordance with the operational performance of the relay 10.

Therefore, when the human sensor 70 detects a person, the switching device 1 turns on the lighting load 300 and causes the fan load 400 to perform the ventilation. The switching device 1 turns on the illumination load 300 by switching the state of the bidirectional thyristor 12 from the off state to the on state, so that the fusion of the contacts 101 caused by the inrush current flowing at the beginning of the opening step is suppressed. The switching device 1 causes a current to flow to the lighting load 300 via the contact 101 after the first delay period and the second delay period have elapsed since the lighting load 300 was turned on. Therefore, the heat generation of the two-way thyristor 12 caused by the current carrying or the power loss in the two-way thyristor 12 can be reduced.

In the first state in which the exciting current flows through the relay coils 102 and 112, the exciting current flows from the rectifier DB1 to the relay coils 102 and 112 via the Zener diode ZD2 and the transistor 31. In the present embodiment, the capacitor C4 is connected between the emitter of the transistor 31 and the ground of the circuit, so that the voltage input from the rectifier DB1 via the gate diode ZD2 and the transistor 31 is smoothed by the capacitor C4. To a substantially constant voltage. The voltage smoothed by the capacitor C4 is applied to the relay coils 102 and 112 so that a steady current can flow through the relay coils 102 and 112. Here, the Zener diode ZD2 and the transistor 31 constitute a first current path RT1 through which current flows from the AC power source 200 to the first drive circuit 20. The second current path RT2 includes a resistor R6 different from the first current path RT1 such that the impedance of the second current path RT2 is higher than the impedance of the first current path RT1. Therefore, compared with the first state in which the exciting current flows through the relay coils 102 and 112, the current flowing from the AC power source 200 to the switching circuit 30 can be suppressed in the second state in which the exciting current does not flow through the relay coils 102 and 112, And can reduce standby power.

Next, the operation of the switching device 1 when the person leaves the detection area of the human sensor 70 in a state where the lighting load 300 is turned on and the fan load 400 is performing the ventilation is described.

When all the people leave the detection area of the human sensor 70, the detection signal input from the human sensor 70 to the signal processing unit 40 is stopped. After a predetermined operation holding period elapses from the time when the input of the detection signal is stopped, the signal processing unit 40 performs the following operations to turn off the lighting load 300 and stop the fan load 400.

After the preset operation holding period elapses from the time when the input of the detection signal from the human sensor 70 is stopped, the signal processing unit 40 switches the voltage levels of the outputs 埠P1 and P2 from the high level to the low level. The signal processing unit 40 maintains the voltage level of the output 埠P3 at a low level. In this case, current does not flow through the relay coils 102 and 112, the contacts 101 and 111 are switched from the on state to the off state, the illumination load 300 is turned off, and the ventilation by the fan load 400 is stopped.

Here, the fan load 400 is an inductive load, so that a back electromotive force that is several times larger than the rated voltage occurs when the ventilation by the fan load 400 is stopped.

When the switching device 1 does not include the surge absorbing circuit 60, and the stray capacitance is generated between the wires connected to the load terminal 94 and the wires connected to the load terminal 95 (because the wires are in proximity to each other), the fan load is applied. The counter electromotive force occurring in 400 can enter the optical coupler 51. When the counter electromotive force that has occurred in the fan load 400 enters the photocoupler 51 and a voltage higher than the on-voltage is applied to the bidirectional thyristor 512, the bidirectional thyristor 512 and the bidirectional thyristor 12 are turned on for a short time. The lighting load 300 includes an LED (as a light source) that has a higher responsiveness to the blazing lamp, such that the lighting load 300 can be briefly turned on by the short-circuiting of the bi-directional thyristor 512 and the bi-directional thyristor 12 .

In the switching device 1 of the present embodiment, the surge absorbing circuit 60 formed by the series circuit of the resistor R4 and the capacitor C2 is connected in parallel to the bidirectional thyristor 12. In other words, the surge absorbing circuit 60 is connected in parallel to the series circuit of the resistor R2, the bidirectional thyristor 512, and the resistor R3. Therefore, even if a counter electromotive force occurs in the fan load 400 when the contact 111 is closed, the voltage rise becomes gentle, and the surge voltage applied to the bidirectional thyristor 512 is performed on the capacitor C2 through the transimpedance resistor R4. Reduced by charging. Therefore, the counter electromotive force occurring in the fan load 400 is less likely to cause the conduction of the bidirectional thyristor 512 and is less likely to cause the illumination load 300 to be briefly illuminated. The surge absorbing circuit 60 is not limited to the RC series circuit of the resistor R4 and the capacitor C4. The surge absorbing circuit 60 can be other circuit configurations or varistors.

The signal processing unit 40 stops the loads (the lighting load 300 and the fan load 400) after the preset operation holding period has elapsed since the time when the human sensor 70 stopped the detection of the human. However, the operation hold period may be preset or adjustable. For example, the switching device 1 may include a setting switch (for example, a toggle switch or a rotary switch), and the setting period may be used to set the operation holding period to a desired period. The signal processing unit 40 may turn off the lighting load 300 and stop the fan load 400 immediately after the input of the detection signal from the human sensor 70 is stopped (ie, the human sensor 70 stops the detection of a human).

As explained above, the switching device 1 of the present embodiment includes the relays 10 and 11 (switching elements), the first driving circuit 20 (driving circuit), and the switching circuit 30. The junction 101 of the relay 10 is inserted into and electrically connected to an electrical path connecting the AC power source 200 to the lighting load 300 (load). The contact 111 of the relay 11 is inserted in an electrical path connecting the AC power source 200 to the fan load 400 (load) and is electrically connected to the electrical path. The first drive circuit 20 is configured to receive power required to drive the relays 10 and 11 from the AC power source 200, and selectively switch the contact states of the relays 10 and 11 to either the first state and the second state. When the contact state is the first state, the switch circuit 30 causes current to flow from the AC power source 200 through the first current path RT1 to the first drive circuit 20. When the contact state is the second state, the switching circuit 30 changes the path through which the current is driven, such that the first current path RT1 is interrupted and the current is driven to flow from the AC power source 200 to the second current path RT2, the second current Path RT2 has a higher impedance than the impedance of the first current path RT1.

Therefore, when the contact state is the second state, the current from the AC power source 200 passes through the second current path RT2 to have a higher impedance than the impedance of the first current path RT1. Therefore, compared to the first state in which current flows through the first driving circuit 20, the current input from the AC power source 200 is reduced in the second state in which current does not flow through the first driving circuit 20, and thus can be lowered The power consumed in the standby state (the first drive circuit 20 does not drive the relays 10 and 11 in this standby state).

In addition, the switching device 1 of the present embodiment may include two relays 10 and 11. The number of relays as the switching elements is not limited to two, but may be three or more, and may be appropriately changed. In contrast to the example in which the switching device 1 includes a switching element, in the example in which the switching device 1 includes a plurality of switching elements, the power consumed in the first driving circuit 20 that drives the switching elements increases, while decreasing The effect of the power consumed in the standby state also increases.

The switching device 1 of the present embodiment can further have the following configuration. The switching elements include relays 10 and 11. The switch circuit 30 includes a transistor 31, a resistor R6, and an arrester diode ZD1. The collector and emitter of the transistor 31 are connected to the first current path RT1. A resistor R6 is connected between the collector and the base of the transistor 31. The Zener diode ZD1 is connected between the base and the ground of the switching circuit, and the cathode of the Zener diode ZD1 is connected to the base side. The emitter of the transistor 31 is connected to the relay coils 102 and 112 of the relays 10 and 11. The first current path RT1 is provided with a transistor 31, and the second current path RT2 is provided with a series circuit of a resistor R6 and an arrester diode ZD1.

Here, when the contact state of the relays 10 and 11 is the first state, the exciting current flows through the relay coils 102 and 112 of the relays 10 and 11 via the transistor 31. When the contact state is the second state, current flows from the AC power source 200 to the ground terminal of the switch circuit 30 via the resistor R6 and the sense diode ZD1. Therefore, the current flowing through the second current path RT2 is limited by the resistor R6, so that the current input from the AC power source 200 is lowered in the second state and the standby state can be lowered (in the standby state) compared to the first state. The power consumed by the first drive circuit 20 does not drive the relays 10 and 11).

In the above-described switching device 1 of the present invention, the relays 10 and 11 are non-latch relays. However, relays 10 and 11 can be latched relays. In the example where relays 10 and 11 are latching relays, each of relays 10 and 11 includes a contact, a set coil, and a reset coil. When current flows through the action coil, the contact is turned on, and even when the current carried to the action coil is stopped, the open state of the contact remains. When current flows through the return coil, the contact is closed, and even when the current carried to the return coil stops, the closed state of the contact remains.

In the switching device 1 of the present embodiment, the lighting load 300 and the fan load 400 are used as loads. However, the load of the switching device 1 is not limited to the lighting load 300 and the fan load 400, and may be other electrical devices.

The switching device 1 of the present embodiment controls the operation of the load based on the detection signal input from the human sensor 70 (as a triggering mode). However, the triggering method for changing the operational state of the load is not limited to the detection result of the human sensor 70 for a person. The switching device 1 can change the operational state of the load by using the operation performed by the operation unit or the receiving unit of the radio signal transmitted from the remote control transmitter as a trigger mode.

Although the present invention has been described with reference to the preferred embodiments thereof, many modifications and variations can be made without departing from the true spirit and scope of the invention.

1‧‧‧Switching device
10‧‧‧ Relay
11‧‧‧ Relay
12‧‧‧Two-way thyristor
20‧‧‧First drive circuit
21‧‧‧Switching elements
22‧‧‧Switching elements
30‧‧‧Switch circuit
31‧‧‧Optoelectronics
40‧‧‧Signal Processing Unit
50‧‧‧second drive circuit
51‧‧‧Optocoupler
52‧‧‧Switching elements
60‧‧‧ surge absorption circuit
70‧‧‧human sensor
80‧‧‧Power circuit
91‧‧‧Input terminal
92‧‧‧Input terminal
93‧‧‧Load terminal
94‧‧‧Load terminal
95‧‧‧Load terminal
96‧‧‧Load terminal
101‧‧‧Contacts
102‧‧‧Relay coil
111‧‧‧Contacts
112‧‧‧Relay coil
200‧‧‧AC power supply
300‧‧‧Lighting load
400‧‧‧fan load
511‧‧‧Light Emitting Diodes (LEDs)
512‧‧‧Two-way thyristor
C1‧‧‧ capacitor
C2‧‧‧ capacitor
C3‧‧‧ capacitor
C4‧‧‧ capacitor
D1‧‧‧ diode
D2‧‧‧ diode
DB1‧‧‧Rectifier
DB11‧‧‧DC output terminal
DB12‧‧‧DC output terminal
Gl‧‧ ‧ gate terminal
L1‧‧‧ coil
P1‧‧‧ Output埠
P2‧‧‧ Output埠
P3‧‧‧ Output埠
RT1‧‧‧First current path
RT2‧‧‧second current path
R1‧‧‧Resistors
R2‧‧‧ resistor
R3‧‧‧Resistors
R4‧‧‧Resistors
R5‧‧‧Resistors
R6‧‧‧Resistors
R7‧‧‧Resistors
R10‧‧‧Resistors
R11‧‧‧Resistors
T1‧‧‧ terminal
T2‧‧‧ terminal
ZD1‧‧‧Jenner diode
ZD2‧‧‧Jenner diode

Preferred embodiments of the present invention will now be described in further detail. Other features and advantages of the present invention will be more fully understood from the description of the appended claims.

1‧‧‧Switching device

10‧‧‧ Relay

11‧‧‧ Relay

12‧‧‧Two-way thyristor

20‧‧‧First drive circuit

21‧‧‧Switching elements

22‧‧‧Switching elements

30‧‧‧Switch circuit

31‧‧‧Optoelectronics

40‧‧‧Signal Processing Unit

50‧‧‧second drive circuit

51‧‧‧Optocoupler

52‧‧‧Switching elements

60‧‧‧ surge absorption circuit

70‧‧‧human sensor

80‧‧‧Power circuit

91‧‧‧Input terminal

92‧‧‧Input terminal

93‧‧‧Load terminal

94‧‧‧Load terminal

95‧‧‧Load terminal

96‧‧‧Load terminal

101‧‧‧Contacts

102‧‧‧Relay coil

111‧‧‧Contacts

112‧‧‧Relay coil

200‧‧‧AC power supply

300‧‧‧Lighting load

400‧‧‧fan load

511‧‧‧Light Emitting Diodes (LEDs)

512‧‧‧Two-way thyristor

C1‧‧‧ capacitor

C2‧‧‧ capacitor

C3‧‧‧ capacitor

C4‧‧‧ capacitor

D1‧‧‧ diode

D2‧‧‧ diode

DB1‧‧‧Rectifier

DB11‧‧‧DC output terminal

DB12‧‧‧DC output terminal

G1‧‧‧ gate terminal

L1‧‧‧ coil

P1‧‧‧ Output埠

P2‧‧‧ Output埠

P3‧‧‧ Output埠

RT1‧‧‧First current path

RT2‧‧‧second current path

R1‧‧‧Resistors

R2‧‧‧ resistor

R3‧‧‧Resistors

R4‧‧‧Resistors

R5‧‧‧Resistors

R6‧‧‧Resistors

R7‧‧‧Resistors

R10‧‧‧Resistors

R11‧‧‧Resistors

T1‧‧‧ terminal

T2‧‧‧ terminal

ZD1‧‧‧Jenner diode

ZD2‧‧‧Jenner diode

Claims (3)

a switching device comprising: at least one switching element inserted into an electrical connection path and electrically connected to the electrical connection path, the electrical connection path connecting an alternating current (AC) power source to a load; a driving circuit for The AC power source receives power required to drive the at least one switching element, and selectively switches a contact state of the at least one switching element to a first state and a second state; and a switching circuit, And a path for changing a current to be driven to cause current to be driven from the AC power source to the driving circuit through the first current path when the contact state is the first state, and when the contact state is the In the second state, the first current path is interrupted and current is driven to flow from the AC source to a second current path having a higher impedance than the impedance of the first current path. The switching device of claim 1, wherein the at least one switching element comprises a plurality of switching elements. The switching device of claim 1 or 2, wherein the at least one switching element comprises a relay, the switching circuit comprising: a transistor comprising a collector and an emitter connected to the first current path; a resistor connected between the collector and a base of the transistor; and a gate diode connected between the base and the ground of the switch circuit, and the gate diode A cathode is coupled to one side of the base, the emitter is coupled to a relay coil of the relay, and the second current path includes a series circuit of the resistor and the Zener diode.