CN209982459U

CN209982459U - Two-wire system delay switch circuit with long delay and low power consumption

Info

Publication number: CN209982459U
Application number: CN201920851195.9U
Authority: CN
Inventors: 徐晓光; 徐高翔
Original assignee: ZHENGZHOU WANYONG ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: ZHENGZHOU WANYONG ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2019-06-06
Filing date: 2019-06-06
Publication date: 2020-01-21
Anticipated expiration: 2029-06-06

Abstract

The utility model discloses a two-wire system time delay switch circuit of long time delay low-power consumption, including alternating current power supply, electronic switch and load, still include direct current voltage acquisition circuit, optoelectronic coupler, time delay turn-off control circuit and step-down rectifier circuit, the drive end of electronic switch is connected with optoelectronic coupler's output, direct current voltage acquisition circuit provides direct current power supply for time delay turn-off control circuit; one end of the voltage reduction rectification circuit is connected to an alternating current power supply through a switch, the other end of the voltage reduction rectification circuit is connected to the input end of the delay turn-off control circuit, and the output end of the delay turn-off control circuit is connected with the input end of the photoelectric coupler. The utility model has the functions of instantly switching on the load and time-delay switching off the load, and also has the function of long-distance communication; as long as the load is electrified, the delay turn-off control circuit can obtain stable power supply; meanwhile, after the delay time is reached, the power supply of the delay turn-off control circuit is also cut off, and the whole circuit does not have any power loss any more.

Description

Two-wire system delay switch circuit with long delay and low power consumption

Technical Field

The utility model belongs to delay switch circuit field, concretely relates to two-wire system delay switch circuit of long time delay low-power consumption.

Background

In human life, there are many occasions where a delay switch is needed, such as delay turn-off of an exhaust fan and an illumination lamp. The existing delay switch circuit has the defects of more power consumption, long-term power-on of the circuit when not working, inaccurate timing time, incapability of obtaining long delay time, unreliable work and the like.

Patent CN204068906U discloses a two-wire system delay power-off circuit which can operate in a long-term power-on mode, but which cannot achieve any long delay time. Patent CN201467088U discloses a delay switch, which has the disadvantage that it is not easy to add an instant off switch.

SUMMERY OF THE UTILITY MODEL

To the not enough of existence among the above-mentioned prior art, the utility model aims at providing a two-wire system time delay switch circuit of long time delay low-power consumption.

The purpose of the utility model is realized through the following technical scheme.

A two-wire system time delay switch circuit with long time delay and low power consumption comprises an alternating current power supply, an electronic switch and a load, wherein the alternating current power supply, the electronic switch and the load form a main alternating current loop; the direct-current voltage acquisition circuit acquires direct-current voltage from the main alternating-current circuit when the electronic switch is switched on and provides a direct-current power supply for the time delay turn-off control circuit; one end of the voltage reduction rectification circuit is connected to an alternating current power supply through a switch, the other end of the voltage reduction rectification circuit is added to the input end of the time delay turn-off control circuit, and when the switch is closed, the voltage added to the input end of the time delay turn-off control circuit enables the time delay turn-off control circuit to output a high level; the output end of the delay cut-off control circuit is connected with the input end of the photoelectric coupler, and the output end of the delay cut-off control circuit controls whether the photoelectric coupler is conducted or not by outputting high level or low level, so that whether the electronic switch is conducted or not is controlled.

The voltage reduction rectification circuit comprises an RC circuit, a first diode, a second diode, a third diode and a fourth diode, one end of the RC circuit is connected to an alternating current power supply through a switch, the other end of the RC circuit is connected with anodes of the second diode, the third diode and the fourth diode, cathodes of the second diode, the third diode and the fourth diode are respectively connected with a first input end, a second input end and a third input end of the time delay turn-off control circuit, a cathode of the first diode is respectively connected with anodes of the second diode, the third diode and the fourth diode, an anode of the first diode is grounded, and the RC circuit is formed by connecting a first resistor and a first capacitor in parallel.

The electronic switch comprises a full-bridge rectifier and a one-way silicon controlled rectifier or a field effect triode, the full-bridge rectifier is connected in a main alternating current loop in series, the positive voltage output end of the full-bridge rectifier is connected with the anode of the one-way silicon controlled rectifier or the drain electrode of the field effect triode, the negative voltage output end of the full-bridge rectifier is connected with the cathode of the one-way silicon controlled rectifier or the source electrode of the field effect triode, the control electrode of the one-way silicon controlled rectifier or the grid electrode of the field effect triode is used as the first driving end of the electronic switch, and the cathode.

The electronic switch comprises a full-bridge rectifier, a first triode, a second triode and a fourth resistor, wherein the full-bridge rectifier is connected in a main alternating current loop in series, the positive voltage output end of the full-bridge rectifier is connected with the collector of the first triode and the collector of the second triode, the negative voltage output end of the full-bridge rectifier is connected with the emitter of the second triode, the emitter of the first triode is connected with the base of the second triode, the fourth resistor is connected in parallel between the base of the second triode and the emitter, the base of the first triode is used as the first driving end of the electronic switch, and the emitter of the second triode is used as the second driving end of the electronic switch.

The electronic switch comprises a bidirectional thyristor, two main terminals of the bidirectional thyristor are connected in a main alternating current loop, a control electrode of the bidirectional thyristor is used as a first driving end of the electronic switch, and the main terminal of the bidirectional thyristor, which is connected with the direct current voltage acquisition circuit, is used as a second driving end of the electronic switch.

The delay turn-off control circuit comprises a first NAND gate, a second NAND gate, a third NAND gate, a fourth NAND gate, a fifth resistor, a sixth resistor, a fifth capacitor and a sixth capacitor, the second NAND gate and the third NAND gate are connected into an RS latch circuit, the output end of the first NAND gate is connected with the input end of the second NAND gate, the output end of the third NAND gate is connected with the input end of the fourth NAND gate, the output end of the fourth NAND gate is connected with the first input end of the photoelectric coupler as the output end of the delay turn-off control circuit through an eighth resistor, the cathode of the third diode is connected with the input end of the first NAND gate through a seventh resistor, the cathode of the third diode is grounded through the sixth resistor, the sixth resistor is connected with the sixth capacitor in parallel, the cathode of the fourth diode is connected with the input end of the third NAND gate through the third resistor, and the cathode of the fourth diode is grounded through the fifth resistor, a fifth capacitor is connected in parallel to the fifth resistor, and a first TVS diode and a piezoresistor are connected in parallel to two ends of the direct current power supply ends of the first NAND gate, the second NAND gate, the third NAND gate and the fourth NAND gate; the cathode of the second diode is grounded through the second TVS diode, the cathode of the second diode is connected to the output end of the time delay turn-off control circuit through the ninth resistor, the output end of the time delay turn-off control circuit is connected with the seventh capacitor, and the other end of the seventh capacitor is grounded.

The time-delay turn-off circuit comprises a singlechip system and a third triode, the output voltage end of the direct-current voltage acquisition circuit is connected with the direct-current power end of the singlechip, the two ends of the direct-current power end of the singlechip are sequentially connected with an eighth capacitor in parallel, one end of a thirteenth resistor is connected to a direct-current power supply of the single chip microcomputer, the other end of the thirteenth resistor is connected with a collector of a third triode, the collector of the third triode is connected with the input end of the single chip microcomputer system, an emitter of the third triode is grounded, a cathode of a second diode is connected with a base electrode of the third triode through a twelfth resistor, an output end of the single chip microcomputer system is connected with a first input end of a photoelectric coupler through a tenth resistor as an output end of a delay turn-off control circuit, a cathode of the third diode is grounded through a second TVS diode, and a cathode of the third diode is connected to an output end of the delay turn-off control circuit through an eleventh resistor.

The electronic switch is a normally open contact of the relay, the time delay turn-off control circuit comprises a fifth NOT gate, a sixth NOT gate, a coil of the relay and a third triode, a voltage output end of the direct-current voltage acquisition circuit is connected with direct-current power supply ends of the fifth NOT gate and the sixth NOT gate, a collector electrode of the third triode is connected to the direct-current power supply end, a cathode of a second diode is connected to the direct-current power supply end, a cathode of the third diode is grounded through a sixth resistor, a sixth capacitor is connected in parallel to the sixth resistor, a cathode of the third diode is connected with an input end of the fifth NOT gate through a seventh resistor, an output end of the fifth NOT gate is connected with an input end of the sixth NOT gate, an output end of the sixth NOT gate is connected with a base electrode of the third triode, an emitter electrode of the third triode is connected with one end of the coil of the relay, the other end of the coil of the relay is, the anode of the fifteenth diode is grounded, and the two ends of the direct current power supply end are connected with the second capacitor, the third capacitor, the first TVS diode and the piezoresistor in parallel.

The photoelectric coupler is a silicon controlled output type optical coupler or a photovoltaic output type optical coupler.

The direct-current voltage acquisition circuit is an arm of the rectification full bridge when the electronic switch comprises the rectification full bridge and is formed by connecting a ninth diode to a fourteenth diode in series; when the electronic switch does not comprise a rectification full bridge, the electronic switch is a TVS diode or a voltage stabilizing diode, the voltage stabilizing diode is connected in a main alternating current loop in series in an inverted mode, the anodes of the ninth diode to the fourteenth diode or the cathode of the voltage stabilizing diode are connected with the anode of the fifth diode, the cathode of the fifth diode is used as the voltage output end of the direct current voltage acquisition circuit, and the cathodes of the ninth diode to the fourteenth diode or the anode of the voltage stabilizing diode are simultaneously used as the grounding end of the direct current voltage acquisition circuit.

Compared with the prior art, the beneficial effects of the utility model are that: the utility model provides a time delay turn-off control circuit has timing function.

The utility model discloses a delay switch circuit has the function of putting through the load immediately and turn off the load with the time delay under switch SW's effect.

The utility model discloses in, as long as switch SW is closed, the load is just circular telegram work, consequently the utility model discloses a delay switch circuit still possesses long logical function.

In the utility model, as long as the load is electrified, the delay turn-off control circuit can obtain stable power supply; meanwhile, after the delay time is reached, the power supply of the delay turn-off control circuit is also cut off, and the whole circuit does not have any power loss any more.

The utility model discloses a delay switch circuit reliable operation, long-term operation's security are high, are suitable for mass production and popularization and application.

Drawings

Fig. 1 is a block diagram of the circuit configuration of the present invention.

Fig. 2 is a schematic circuit diagram of the electronic switch of the present invention.

Fig. 3 is a schematic circuit diagram of the electronic switch of the present invention.

Fig. 4 is a schematic circuit diagram of the electronic switch of the present invention.

Fig. 5 is a schematic circuit diagram of the electronic switch of the present invention.

Fig. 6 is a schematic circuit diagram according to embodiment 1 of the present invention.

Fig. 7 is a schematic circuit diagram according to embodiment 2 of the present invention.

Fig. 8 is a schematic circuit diagram according to embodiment 3 of the present invention.

Fig. 9 is a schematic circuit diagram according to embodiment 4 of the present invention.

Detailed Description

As shown in fig. 1, the two-wire delay switch circuit with long delay and low power consumption includes an ac power supply, an electronic switch, a LOAD, a dc voltage acquisition circuit, a photoelectric coupler PC, a delay turn-off control circuit, and a step-down rectification circuit, where the ac power supply, the electronic switch, and the LOAD form a main ac loop. The on-off of the electronic switch is controlled by the driving end of the electronic switch, the driving end of the electronic switch is connected with the output end of a photoelectric coupler PC, and the photoelectric coupler PC controls the on-off of the electronic switch; the direct-current voltage acquisition circuit acquires direct-current voltage from the main alternating-current circuit when the electronic switch is switched on and provides a direct-current power supply for the time delay turn-off control circuit; one end of the voltage reduction rectification circuit is connected to an alternating current power supply through a switch SW, the other end of the voltage reduction rectification circuit is added to the input end of the delay turn-off control circuit, and when the switch SW is closed, the voltage added to the input end of the delay turn-off control circuit enables the delay turn-off control circuit to output a high level; the output end of the delay cut-off control circuit is connected with the input end of the photoelectric coupler PC, and the output end of the delay cut-off control circuit controls whether the photoelectric coupler PC is conducted or not by outputting high level or low level, so that whether the electronic switch is conducted or not is controlled.

The on-off of the electronic switch is controlled by the first driving end G1 and the second driving end G2, the first output end O1 and the second output end O2 of a photoelectric coupler PC are connected to the first driving end G1 and the second driving end G2, and the photoelectric coupler PC controls the on-off of the electronic switch. The photoelectric coupler PC is driven by a time delay turn-off control circuit, and the on-off of the photoelectric coupler PC is controlled by a first input end L1 and a second input end L2. The direct current power supply of the time delay turn-off control circuit is obtained by a direct current voltage acquisition circuit which is connected in series in the main alternating current loop. When the electronic switch is switched on, load current flows through the direct current voltage acquisition circuit to generate direct current voltage to supply the delay switching-off control circuit for a direct current power supply. When the electronic switch is turned off, the load current is cut off, and the DC power supply of the delayed turn-off control circuit is lost. Therefore, after the electronic switch is turned on, the delay turn-off control circuit can obtain stable direct-current power supply from the direct-current voltage acquisition circuit, so that delay time of any duration can be obtained. The delay turn-off control circuit is a circuit with the functions of timing and the like.

When the switch SW is closed, the ac power supply is applied to the input terminal of the delay off control circuit through the step-down rectifier circuit, and the voltage at the input terminal of the delay off control circuit makes the output terminal OUT of the delay off control circuit output a high level, so that the photoelectric coupler PC is turned on, the electronic switch is driven to be turned on, and the LOAD is electrified to work.

When the switch SW is switched off, the voltage applied to the input end of the delay turn-off control circuit by the alternating current power supply through the voltage reduction rectification circuit disappears, a delay command signal is sent out, the delay turn-off control circuit is enabled to enter a timing state, and timing is started. Before the timing time of the delay turn-off control circuit is reached, the output end OUT of the delay turn-off control circuit keeps a high level, so that the LOAD LOAD keeps an electrified working state. And after the timing time is up, the output end OUT of the delay turn-off control circuit outputs low level to turn off the photoelectric coupler PC, so that the electronic switch is switched off, and the LOAD LOAD is cut off.

Example 1

As shown in fig. 1, 3 and 6, the electronic switch includes a one-way thyristor SCR, a rectifying full bridge composed of a sixth diode D6 to a fourteenth diode D14, a second resistor R2, a fourth resistor R4 and a fourth capacitor C4. The photoelectric coupler PC is a silicon controlled output type photoelectric coupler. The direct-current voltage acquisition circuit is served by the ninth to fourteenth diodes D9 to D14 and the fifth diode D5. The first resistor R1, the first capacitor C1, the first diode D1, the second diode D2, the third diode D3 and the fourth diode D4 form a step-down rectifying circuit. SW is a switch. LOAD is the LOAD. The other electronic components, such as the first nand gate Y1 to the fourth nand gate Y4, the fifth resistor R5, the eighth resistor R8, the ninth resistor R9, the fifth capacitor C5, and the like, form a delay-off control circuit.

The positive voltage output end of the rectifying full bridge is connected with the anode of the unidirectional Silicon Controlled Rectifier (SCR), the negative voltage output end of the rectifying full bridge is connected with the cathode of the unidirectional Silicon Controlled Rectifier (SCR), the control electrode of the unidirectional Silicon Controlled Rectifier (SCR) serves as the first driving end G1 of the electronic switch, and the cathode of the unidirectional Silicon Controlled Rectifier (SCR) serves as the second driving end G2 of the electronic switch.

The second NAND gate Y2 and the third NAND gate Y3 of the time-delay turn-off control circuit are connected to form an RS latch circuit, the output end of the first NAND gate Y1 is connected with the input end of the second NAND gate Y2, the output end of the third NAND gate Y3 is connected with the input end of the fourth NAND gate Y4, the output end of the fourth NAND gate Y4 is connected with the first input end L1 of the photoelectric coupler PC through an eighth resistor R8 as the output end OUT of the time-delay turn-off control circuit, and the second input end L2 of the photoelectric coupler PC is grounded. The cathode of the third diode D3 is connected with the input end of the first nand gate Y1 through a seventh resistor R7, the cathode of the third diode D3 is grounded through a sixth resistor R6, a sixth capacitor C6 is connected in parallel to the sixth resistor R6, and the cathode of the sixth capacitor C6 is grounded; the cathode of the fourth diode D4 is connected with the input end of the third nand gate Y3 through the third resistor R3, the cathode of the fourth diode D4 is grounded through the fifth resistor R5, the fifth resistor R5 is connected in parallel with a fifth capacitor C5, and the cathode of the fifth capacitor C5 is grounded; the cathode of the second diode D2 is connected to the cathode of the second TVS diode VD2, the anode of the second TVS diode VD2 is grounded, the cathode of the second diode D2 is connected to the output terminal OUT of the delay off control circuit through the ninth resistor R9, the output terminal OUT is connected to the seventh capacitor C7, and the other end of the seventh capacitor C7 is grounded.

The cathode of the fifth diode D5 of the dc voltage acquisition circuit serves as the voltage output terminal CC. The voltage output terminal CC of the dc voltage obtaining circuit is connected to the dc power terminal VCC of the first nand gate Y1 to the fourth nand gate Y4. The two ends of the direct current power supply terminal VCC are connected in parallel with a second capacitor C2, a third capacitor C3, a first TVS diode VD1 and a voltage dependent resistor RV.

When the unidirectional silicon controlled rectifier SCR is triggered to be turned on, current flows through the ninth diode D9 to the fourteenth diode D14, and voltages at two ends of the ninth diode D9 to the fourteenth diode D14 are supplied to the first nand gate Y1 to the fourth nand gate Y4 through the fifth diode D5 to serve as direct-current power supply voltages, so long as the unidirectional silicon controlled rectifier SCR is triggered to be turned on, the direct-current power supply of the first nand gate Y1 to the fourth nand gate Y4 is stable. When the one-way SCR turns off, the current flowing through the ninth diode D9 to the fourteenth diode D14 is also zero, and the dc supply voltage supply of the first nand gate Y1 to the fourth nand gate Y4 is also lost.

The second nand gate Y2 and the third nand gate Y3 are connected to form an RS latch circuit, and the RS latch circuit passes through the fourth nand gate Y4 and then controls the on/off of the photoelectric coupler PC through the eighth resistor R8, thereby controlling the on/off of the unidirectional silicon controlled rectifier SCR.

When the switch SW is closed, the alternating voltage passes through a circuit of the first capacitor C1, the first diode D1, the second diode D2, the second TVS diode VD2 and the ninth resistor R9 to generate a direct current voltage with a proper magnitude to drive the photoelectric coupler PC to be conducted, and trigger the one-way thyristor SCR to be conducted, so that the load is electrified to work.

When the one-way SCR is triggered to turn on, current flows through the ninth diode D9 to the fourteenth diode D14, and the dc voltages of the ninth diode D9 to the fourteenth diode D14 pass through the fifth diode D5 to become the dc power voltage sources of the first nand gate Y1 to the fourth nand gate Y4. At this time, the ac voltage is also charged into the sixth capacitor C6 and the fifth capacitor C5 through the third diode D3 and the fourth diode D4, and as a result, the RS latch formed by the second nand gate Y2 and the third nand gate Y3 outputs a low level, and then outputs a high level through the fourth nand gate Y4.

At this time, as long as the switch SW is closed, the photoelectric coupler PC is turned on, the one-way silicon controlled rectifier SCR is triggered by the turned-on photoelectric coupler PC and the second resistor R2 to be turned on, and the load is in a power-on working state.

Thereafter, when the switch SW is turned off, the dc voltage from the second diode D2, the third diode D3, and the fourth diode D4 disappears, the voltage across the sixth capacitor C6 is discharged quickly, and the voltage across the fifth capacitor C5 needs a certain time to be discharged to a low level. The discharge time is determined by the parameters of the fifth resistor R5 and the fifth capacitor C5.

The state of the RS latch remains unchanged until the voltage on the fifth capacitor C5 does not drop to the input low level of the nand gate, and the output of the fourth nand gate Y4 remains high. The electronic switch is kept on, and the load is kept in a power-on working state.

After the voltage on the fifth capacitor C5 drops to the input low level of the NAND gate, the state of the RS latch is reversed, the output of the fourth NAND gate Y4 is low level, the excitation of the photoelectric coupler PC disappears, the one-way silicon controlled rectifier SCR is turned off, and the LOAD LOAD is in a power-off working state. This state is maintained until the next time the switch SW is closed. Preventing malfunction when the state changes.

When the timing time is up, after the output of the fourth nand gate Y4 changes from high level to low level, the latch can be turned over by the high level signal of the fifth capacitor C5 only when the voltage of the sixth capacitor C6 changes to high level, so that the one-way thyristor SCR is turned on. The phenomenon that the output of the third NAND gate Y3 is changed from low level to high level and then is changed into low level due to the fact that the voltage drop speed of the power supply on the NAND gate circuit is higher than the voltage drop speed of the fifth capacitor C5 when the unidirectional silicon controlled rectifier SCR is turned off is avoided. Thereby avoiding the situation that the electronic switch cannot be reliably turned off.

When the load circular telegram, first NAND gate Y1 to fourth NAND gate Y4 have stable DC power supply to supply, consequently the utility model discloses can realize arbitrary long delay time. And after the delay time reaches the time when the load is turned off, the power supply of the control circuit can be cut off, and the whole circuit has no standby power loss.

The first TVS diode VD1 and the piezoresistor RV in the circuit are connected in parallel at two ends of a direct current power supply terminal VCC of the first NAND gate Y1 to the fourth NAND gate Y4, and the function of protecting the integrated NAND gate circuit from being damaged by overvoltage can be achieved.

Example 2

As shown in fig. 1, 3 and 7, in embodiment 1, the thyristor output type photocoupler PC may be replaced with a photovoltaic output type photocoupler. The delay turn-off control circuit is replaced by a single chip microcomputer system.

The time-delay turn-off circuit comprises a single chip microcomputer system and a third triode TA, a voltage output end CC of the direct-current voltage acquisition circuit is connected with a direct-current power supply end VCC of the single chip microcomputer, a grounding end G of the direct-current voltage acquisition circuit is connected with a grounding end GND of the single chip microcomputer and then grounded, and an eighth capacitor C8, a first TVS diode VD1 and a piezoresistor RV are sequentially connected in parallel at two ends of the direct-current power supply end VCC of the single chip microcomputer and used for protecting the single chip microcomputer from being damaged by. The collector of the third triode TA is connected to the dc power supply terminal VCC by a thirteenth resistor RD, and is connected to the input terminal I/O1 of the single chip microcomputer system, the emitter of the third triode TA is grounded, the second diode D2 of the step-down rectification circuit is connected to the base of the third triode TA through a twelfth resistor RC, and the output terminal I/O2 of the single chip microcomputer system is connected to the first input terminal L1 of the photocoupler PC through a tenth resistor RA as the output terminal OUT of the delay off control circuit. The cathode of a third diode D3 in the step-down rectification circuit is connected to the output end OUT of the time-delay turn-off control circuit through an eleventh resistor RB, the cathode of a third diode D3 is grounded through a second TVS diode VD2, and the second TVS diode VD2 plays a role in clamping and limiting voltage.

When the switch SW is closed, the alternating voltage is changed into direct voltage by the third diode D3 after passing through the voltage reduction rectification circuit to drive the photoelectric coupler PC to output voltage and trigger the one-way silicon controlled rectifier SCR to be conducted. The direct current voltage acquisition circuits from the ninth diode D9 to the fourteenth diode D14 generate direct current power supply voltage supply of the singlechip microcomputer system. Meanwhile, when direct current voltage exists, the third triode TA is conducted, a low level signal is given out from an I/O1 port of the single chip microcomputer, and a high level is output from an I/O2 port of the single chip microcomputer through a single chip microcomputer system.

When the switch SW is turned off, the low signal at the I/O1 port disappears and goes high. The singlechip starts timing work, the I/O2 port keeps high level output before the timing time is reached, and the load keeps an electrified working state through the photoelectric coupler PC and the unidirectional silicon controlled rectifier SCR. When the delay time is up, the port of the singlechip I/O2 outputs low level, and the unidirectional silicon controlled rectifier SCR is turned off through the photoelectric coupler PC to cut off the working current of the load.

The single chip microcomputer system can enable the delay switch circuit to have more accurate delay time parameters, and the circuit can also have long delay time.

Example 3

As shown in fig. 1, 2 and 8, in embodiment 1, the electronic switch may be replaced with a triac TR. The direct current voltage acquisition circuit is replaced by a voltage stabilizing diode DZ or a TVS diode.

Example 4

As shown in fig. 1 and 9, in embodiment 1, the electronic switch is replaced with a normally open contact of the relay J. The direct current voltage acquisition circuit adopts a voltage stabilizing diode DZ. The delay turn-off control circuit is composed of a fifth NOT gate Y5, a sixth NOT gate Y6, a third triode TA, a coil of a relay J and the like.

The electronic switch is a normally open contact of the relay J, the delay turn-off control circuit comprises a fifth NOT gate Y5, a sixth NOT gate Y6, a coil of the relay J and a third triode TA, an output voltage end CC and a fifth NOT gate Y5 of the direct-current voltage acquisition circuit are connected with a direct-current power supply end VCC of the sixth NOT gate Y6, a collector of the third triode TA is connected to the direct-current power supply end VCC, a cathode of a second diode D2 is connected to the direct-current power supply end VCC, a cathode of a third diode D3 is grounded through a sixth resistor R6, a sixth capacitor C6 is connected in parallel to a sixth resistor R6, and a cathode of the sixth capacitor C6 is grounded. The cathode of the third diode D3 is connected with the input end of the fifth not gate Y5 through the seventh resistor R7, the output end of the fifth not gate Y5 is connected with the input end of the sixth not gate Y6, the output end of the sixth not gate Y6 is connected with the base of the third triode TA, the emitter of the third triode TA is connected with one end of the coil of the relay J, the other end of the coil of the relay J is grounded, the two ends of the coil of the relay J are connected in parallel with the fifteenth diode D15, the anode of the fifteenth diode D15 is grounded, and the two ends of the dc power source VCC are connected in parallel with the second capacitor C2, the third capacitor C3, the first TVS diode VD1 and the piezoresistor RV.

Further, fig. 4 and 5 are both alternative circuits of the electronic switch.

The electronic switch in fig. 4 includes a rectifying full bridge, a first triode T1, a second triode T2 and a fourth resistor R4, the rectifying full bridge is connected in series in the main ac loop, a positive voltage output terminal of the rectifying full bridge is connected with a collector of the first triode T1 and a collector of the second triode T2, a negative voltage output terminal of the rectifying full bridge is connected with an emitter of the second triode T2, an emitter of the first triode T1 is connected with a base of the second triode T2, a fourth resistor R4 is connected in parallel between the base and the emitter of the second triode T2, the base of the first triode T1 serves as a first driving terminal G1 of the electronic switch, and the emitter of the second triode T2 serves as a second driving terminal G2 of the electronic switch.

The electronic switch of fig. 5 includes a rectifying full bridge and a FET, the rectifying full bridge is connected in series in the main ac loop, a positive voltage output terminal of the rectifying full bridge is connected to a drain of the FET, a negative voltage output terminal of the rectifying full bridge is connected to a source of the FET, a gate of the FET serves as a first driving terminal G1 of the electronic switch, and a source of the FET serves as a second driving terminal G2 of the electronic switch.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical solutions of the present invention, and it should be noted that, further improvements and changes can be made by those skilled in the art on the premise of the technical solutions of the present invention, and all such improvements and changes should be covered by the protection scope of the present invention.

Claims

1. The utility model provides a two-wire system time delay switch circuit of long time delay low-power consumption, includes alternating current power supply, electronic switch and load, and alternating current power supply, electronic switch and load constitute main interchange return circuit, its characterized in that: the direct current voltage acquisition circuit is connected with the input end of the electronic switch (PC), and the Photoelectric Coupler (PC) controls the on/off of the electronic switch; the direct-current voltage acquisition circuit acquires direct-current voltage from the main alternating-current circuit when the electronic switch is switched on and provides a direct-current power supply for the time delay turn-off control circuit; one end of the voltage reduction rectification circuit is connected to an alternating current power supply through a Switch (SW), the other end of the voltage reduction rectification circuit is added to the input end of the delay turn-off control circuit, and when the Switch (SW) is closed, the voltage added to the input end of the delay turn-off control circuit enables the delay turn-off control circuit to output high level; the output end of the delay cut-off control circuit is connected with the input end of the Photoelectric Coupler (PC), and the output end of the delay cut-off control circuit controls whether the Photoelectric Coupler (PC) is conducted or not by outputting high level or low level, so that whether the electronic switch is conducted or not is controlled.

2. The two-wire delay switch circuit of claim 1, wherein: the buck rectifying circuit comprises an RC circuit, a first diode (D1), a second diode (D2), a third diode (D3) and a fourth diode (D4), one end of the RC circuit is connected to an alternating current power supply through a Switch (SW), the other end of the RC circuit is connected with the second diode (D2), anodes of the third diode (D3) and the fourth diode (D4) are connected, cathodes of the second diode (D2), the third diode (D3) and the fourth diode (D4) are respectively connected with the first input end (V1), the second input end (V2) and the third input end (V3) of the time delay turn-off control circuit, a cathode of the first diode (D1) is respectively connected with anodes of the second diode (D2), the third diode (D3) and the fourth diode (D4), an anode of the first diode (D1) is grounded, and the RC circuit is formed by connecting the first resistor (R1) and the first capacitor (C1) in parallel.

3. The two-wire delay switch circuit of claim 1, wherein: the electronic switch comprises a full-bridge rectifier and a unidirectional Silicon Controlled Rectifier (SCR) or a Field Effect Transistor (FET), wherein the full-bridge rectifier is connected in a main alternating current loop in series, the positive voltage output end of the full-bridge rectifier is connected with the anode of the unidirectional Silicon Controlled Rectifier (SCR) or the drain of the Field Effect Transistor (FET), the negative voltage output end of the full-bridge rectifier is connected with the cathode of the unidirectional Silicon Controlled Rectifier (SCR) or the source of the Field Effect Transistor (FET), the control electrode of the unidirectional Silicon Controlled Rectifier (SCR) or the grid of the Field Effect Transistor (FET) serve as a first driving end (G1) of the electronic switch, and the cathode of the unidirectional Silicon Controlled Rectifier (SCR) or the source of the Field Effect Transistor (FET) serve as.

4. The two-wire delay switch circuit of claim 1, wherein: the electronic switch comprises a rectifying full bridge, a first triode (T1), a second triode (T2) and a fourth resistor (R4), wherein the rectifying full bridge is connected in the main alternating current loop in series, a positive voltage output end of the rectifying full bridge is connected with a collector of the first triode (T1) and a collector of the second triode (T2), a negative voltage output end of the rectifying full bridge is connected with an emitter of the second triode (T2), an emitter of the first triode (T1) is connected with a base of the second triode (T2), the fourth resistor (R4) is connected between the base and the emitter of the second triode (T2) in parallel, the base of the first triode (T1) serves as a first driving end (G1) of the electronic switch, and the emitter of the second triode (T2) serves as a second driving end (G2) of the electronic switch.

5. The two-wire delay switch circuit of claim 1, wherein: the electronic switch comprises a bidirectional triode Thyristor (TR), two main terminals of the bidirectional triode Thyristor (TR) are connected in a main alternating current loop, a control electrode of the bidirectional triode Thyristor (TR) is used as a first driving end (G1) of the electronic switch, and a main terminal of the bidirectional triode Thyristor (TR) connected with a direct current voltage acquisition circuit is used as a second driving end (G2) of the electronic switch.

6. The two-wire delay switch circuit of claim 2, wherein: the delay turn-off control circuit comprises a first NAND gate (Y1), a second NAND gate (Y2), a third NAND gate (Y3), a fourth NAND gate (Y4), a fifth resistor (R5), a sixth resistor (R6), a fifth capacitor (C5) and a sixth capacitor (C6), wherein the second NAND gate (Y2) and the third NAND gate (Y3) are connected into an RS latch circuit, the output end of the first NAND gate (Y1) is connected with the input end of the second NAND gate (Y2), the output end of the third NAND gate (Y3) is connected with the input end of the fourth NAND gate (Y4), the output end of the fourth NAND gate (Y4) is used as the output end (OUT) of the delay turn-off control circuit through an eighth resistor (R8) and is connected with the first input end (L1) of the Photoelectric Coupler (PC), the cathode of the third diode (D3) is connected with the input end of the first NAND gate (Y1) through a seventh resistor (R7), the cathode of the third diode (D3) is grounded through a sixth resistor (R6), a sixth capacitor (C6) is connected to the sixth resistor (R6) in parallel, the cathode of the fourth diode (D4) is connected with the input end of a third NAND gate (Y3) through a third resistor (R3), the cathode of the fourth diode (D4) is grounded through a fifth resistor (R5), a fifth capacitor (C5) is connected to the fifth resistor (R5) in parallel, and the two ends of the direct current power source end (VCC) of the first NAND gate (Y1), the second NAND gate (Y2), the third NAND gate (Y3) and the fourth NAND gate (Y4) are connected with a first TVS diode (VD 1) and a piezoresistor (RV) in parallel; the cathode of the second diode (D2) is grounded through the second TVS diode (VD 2), the cathode of the second diode (D2) is connected to the output end (OUT) of the time delay turn-off control circuit through a ninth resistor (R9), the output end (OUT) is connected with a seventh capacitor (C7), and the other end of the seventh capacitor (C7) is grounded.

7. The two-wire delay switch circuit of claim 2, wherein: the time-delay turn-off circuit comprises a single chip microcomputer system and a third Triode (TA), a voltage output end (CC) of the direct-current voltage acquisition circuit is connected with a direct-current power supply end (VCC) of the single chip microcomputer, an eighth capacitor (C8), a first TVS diode (VD 1) and a piezoresistor (RV) are sequentially connected in parallel at two ends of the direct-current power supply end (VCC) of the single chip microcomputer, one end of a thirteenth Resistor (RD) is connected to the direct-current power supply end (VCC) of the single chip microcomputer, the other end of the thirteenth Resistor (RD) is connected with a collector of the third Triode (TA), the collector of the third Triode (TA) is connected with an input end (I/O1) of the single chip microcomputer system, an emitter of the third Triode (TA) is grounded, a cathode of a second diode (D2) is connected with a base of the third Triode (TA) through a twelfth Resistor (RC), an output end (I/O2) of the single chip microcomputer system serves as an output end (OUT) of the time-delay turn And the cathode of the third diode (D3) is grounded through the second TVS diode (VD 2), and the cathode of the third diode (D3) is connected to the output end (OUT) of the time delay turn-off control circuit through the eleventh Resistor (RB).

8. The two-wire delay switch circuit of claim 2, wherein: the electronic switch is a normally open contact of a relay (J), the time delay turn-off control circuit comprises a fifth NOT gate (Y5), a sixth NOT gate (Y6), a coil of the relay (J) and a third Triode (TA), a voltage output end (CC) of the direct-current voltage acquisition circuit is connected with the fifth NOT gate (Y5) and a direct-current power supply end (VCC) of the sixth NOT gate (Y6), a collector of the third Triode (TA) is connected to the direct-current power supply end (VCC), a cathode of a second diode (D2) is connected to the direct-current power supply end (VCC), a cathode of a third diode (D3) is grounded through a sixth resistor (R6), a sixth resistor (R6) is connected with a sixth capacitor (C6) in parallel, a cathode of the third diode (D3) is connected with input ends of the fifth NOT gate (Y5) through a seventh resistor (R7), an output end of the fifth NOT gate (Y5) is connected with an input end of the sixth NOT gate (Y6), the output end of the sixth not gate (Y6) is connected with the base of the third Triode (TA), the emitter of the third Triode (TA) is connected with one end of the coil of the relay (J), the other end of the coil of the relay (J) is grounded, the two ends of the coil of the relay (J) are connected in parallel with a fifteenth diode (D15), the anode of the fifteenth diode (D15) is grounded, the two ends of the direct current power supply end (VCC) are connected in parallel with a second capacitor (C2), a third capacitor (C3), a first TVS diode (VD 1) and a piezoresistor (RV).

9. The two-wire delay switch circuit of claim 1, wherein: the Photoelectric Coupler (PC) is a silicon controlled output type optical coupler or a photovoltaic output type optical coupler.

10. The long-delay low-power consumption two-wire delay switch circuit according to claim 3, 4 or 5, wherein: the direct-current voltage acquisition circuit is one arm of the rectification full bridge when the electronic switch comprises the rectification full bridge and is formed by connecting a ninth diode (D9) to a fourteenth diode (D14) in series; when the electronic switch does not comprise a rectifying full bridge, the electronic switch is a TVS diode or a voltage stabilizing Diode (DZ), the voltage stabilizing Diode (DZ) is connected in a main alternating current loop in series in an inverted mode, the anode of a fifth diode (D5) is connected to the anodes of a ninth diode (D9) to a fourteenth diode (D14) or the cathode of the voltage stabilizing Diode (DZ), the cathode of the fifth diode (D5) serves as a voltage output end (CC) of the direct current voltage acquisition circuit, and the cathodes of the ninth diode (D9) to the fourteenth diode (D14) or the anode of the voltage stabilizing Diode (DZ) simultaneously serves as a grounding end (G) of the direct current voltage acquisition circuit.