阅读说明：本技术 插座保护电路及插座 (Socket protection circuit and socket ) 是由 张维建 于 2021-08-31 设计创作，主要内容包括：本申请涉及一种插座保护电路及插座,该插座保护电路包括：设置于插座插孔处的红外检测模块、与火线和插套火线端电连接的继电器、电源模块和继电器驱动模块；其中,电源模块分别与红外检测模块和继电器驱动模块电连接,电源模块用于为红外检测模块和继电器驱动模块供电；红外检测模块和继电器均与继电器驱动模块电连接,红外检测模块用于检测插座插孔处是否有电器插头插入,继电器驱动模块用于根据红外检测模块的检测结果,驱动继电器处于导通或断开状态,以控制火线与插套火线端之间进行导通或断开。这样,插座保护电路可以自动检测是否有电器插头插入,并根据检测结果自动控制继电器的导通或断开,以实现插座的自动导通电源或断开电源的功能。(The application relates to a socket protection circuit and socket, this socket protection circuit includes: the infrared detection module is arranged at the socket jack, and the relay, the power supply module and the relay driving module are electrically connected with the live wire and the plug bush live wire end; the power supply module is respectively electrically connected with the infrared detection module and the relay driving module and is used for supplying power to the infrared detection module and the relay driving module; infrared detection module and relay all are connected with relay drive module electricity, and infrared detection module is used for detecting whether socket jack department has the electrical apparatus plug to insert, and relay drive module is used for according to infrared detection module's testing result, and drive relay is in and switches on or the off-state to switch on or break off between control live wire and the plug bush live wire end. Therefore, the socket protection circuit can automatically detect whether an electric appliance plug is inserted, and automatically control the on or off of the relay according to the detection result so as to realize the function of automatically switching on or off the power supply of the socket.)

1. A socket protection circuit is applied to a socket, and the socket comprises: the socket jack and the plug sleeve live wire end are used for connecting a live wire; the socket protection circuit is characterized by comprising an infrared detection module arranged at a socket hole, a relay electrically connected with the live wire and the plug bush live wire end, a power supply module and a relay driving module;

the power supply module is electrically connected with the infrared detection module and the relay driving module respectively, and is used for supplying power to the infrared detection module and the relay driving module;

the infrared detection module and the relay are electrically connected with the relay driving module, the infrared detection module is used for detecting whether an electric appliance plug is inserted into the socket jack, and the relay driving module is used for driving the relay to be in a conducting or disconnecting state according to a detection result of the infrared detection module so as to control the live wire to be conducted or disconnected between the live wire end of the plug bush.

2. The socket protection circuit of claim 1, wherein the infrared detection module comprises: an infrared transmitting unit and an infrared receiving unit;

the infrared transmitting unit and the infrared receiving unit are oppositely arranged on two sides of the socket jack; or the infrared transmitting unit and the infrared receiving unit are arranged on the same side of the socket jack.

3. The socket protection circuit according to claim 2, wherein the infrared emission unit includes an infrared emission tube and a first resistor; the first end of the first resistor is electrically connected with the power supply module, the second end of the first resistor is electrically connected with the anode of the infrared emission tube, and the cathode of the infrared emission tube is electrically connected with the grounding end;

the infrared receiving unit comprises an infrared receiving tube, a first triode, a second resistor and a third resistor; the first end of the second resistor is electrically connected with the power supply module, the second end of the second resistor is respectively electrically connected with the cathode of the infrared receiving tube and the base of the first triode, and the anode of the infrared receiving tube is electrically connected with the ground terminal; the first end of the third resistor is electrically connected with the power supply module, the second end of the third resistor is respectively electrically connected with the collector of the first triode and the relay driving module, and the emitter of the first triode is electrically connected with the grounding end.

4. The socket protection circuit according to claim 1, further comprising a time-delay charge-discharge module, wherein the time-delay charge-discharge module is arranged in series between the infrared detection module and the relay driving module;

the time-delay charging and discharging module is used for controlling the relay driving module to carry out time-delay opening or time-delay closing according to the detection result of the infrared detection module.

5. The socket protection circuit of claim 4, wherein the time delay charge and discharge module comprises: the second triode, the third triode, the first capacitor and the fourth resistor;

the base electrode of the second triode and the base electrode of the third triode are both electrically connected with the infrared detection module, the emitting electrode of the second triode is electrically connected with the first end of the fourth resistor, and the second end of the fourth resistor is electrically connected with the power supply module; and the collector electrode of the second triode is respectively electrically connected with the anode of the first capacitor, the collector electrode of the third triode and the relay driving module, and the cathode of the first capacitor and the emitter electrode of the third triode are electrically connected with a grounding terminal.

6. The receptacle protection circuit of claim 4, wherein the relay drive module comprises: the fourth triode, the fifth triode, the N-channel MOS tube, the fifth resistor and the sixth resistor;

a base electrode of the fourth triode is electrically connected with the delay charging and discharging module, and a collector electrode of the fourth triode is electrically connected with a first end of the fifth resistor and a base electrode of the fifth triode respectively;

a collector of the fifth triode is electrically connected with a first end of the sixth resistor and a gate of the N-channel MOS transistor respectively, a second end of the fifth resistor and a second end of the sixth resistor are electrically connected with the power module, and an emitter of the fourth triode, an emitter of the fifth triode and a source of the N-channel MOS transistor are electrically connected with a ground terminal;

the relay comprises a relay coil, a movable contact and a fixed contact, the relay coil is electrically connected between the drain electrode of the N-channel MOS tube and the power module in series, the fixed contact is electrically connected with the live wire, and the movable contact is electrically connected with the live wire end of the plug bush.

7. The socket protection circuit of claim 6, wherein the relay drive module further comprises a diode;

wherein the diode is arranged in parallel with the relay coil; the anode of the diode is electrically connected with the drain electrode of the N-channel MOS tube, and the cathode of the diode is electrically connected with the power supply module.

8. The socket protection circuit according to claim 1, wherein the power module includes an ac-dc conversion unit and a dc-dc conversion unit;

the input end of the alternating current-direct current conversion unit is electrically connected with a mains supply, the output end of the alternating current-direct current conversion unit is electrically connected with the input end of the direct current-direct current conversion unit, and the output end of the direct current-direct current conversion unit is electrically connected with the infrared detection module and the relay driving module respectively.

9. The socket protection circuit according to claim 8, wherein the power module further comprises at least one filtering unit, an input terminal of the at least one filtering unit being electrically connected to an output terminal of the ac-dc conversion unit and/or an output terminal of the dc-dc conversion unit.

10. A socket comprising a socket receptacle, a jacketed hot wire end for connecting to a hot wire, and a socket protection circuit according to any one of claims 1 to 9.

Technical Field

The application relates to the technical field of electric appliances, in particular to a socket protection circuit and a socket.

Background

When the socket is in a power-on state and is plugged with a power-supply load, the capacitor element is equivalent to a short circuit at the moment when the power-supply load is switched on, and an impact current can occur. In addition, because the contact area between the socket plug bush and the electric appliance plug is small and the gap between the socket plug bush and the electric appliance plug is small, impact current can ionize air media to generate sparks, and therefore serious potential safety hazards exist.

In order to avoid the potential safety hazard, when the socket is used, a user needs to manually turn off the socket power supply before an electric appliance plug is inserted into the socket and manually turn on the socket power supply after the electric appliance plug is inserted into the socket, so that the problem that the user is complicated to operate when using the socket can be caused.

Disclosure of Invention

The application provides a socket protection circuit and a socket to solve the problem that the existing socket needs to be manually disconnected from a socket power supply by a user before an electric appliance plug is inserted into the socket, and then the socket power supply is manually switched on after the electric appliance plug is inserted into the socket, so that the user can use the socket in a complex operation mode.

In a first aspect, the present application provides a socket protection circuit applied to a socket, the socket including: the socket jack and the plug sleeve live wire end are used for connecting a live wire; the socket protection circuit comprises an infrared detection module arranged at the socket jack, a relay electrically connected with the live wire and the plug bush live wire end, a power supply module and a relay driving module;

the power supply module is electrically connected with the infrared detection module and the relay driving module respectively, and is used for supplying power to the infrared detection module and the relay driving module;

the infrared detection module and the relay are electrically connected with the relay driving module, the infrared detection module is used for detecting whether an electric appliance plug is inserted into the socket jack, and the relay driving module is used for driving the relay to be in a conducting or disconnecting state according to a detection result of the infrared detection module so as to control the live wire to be conducted or disconnected between the live wire end of the plug bush.

Optionally, the infrared detection module includes: an infrared transmitting unit and an infrared receiving unit;

the infrared transmitting unit and the infrared receiving unit are oppositely arranged on two sides of the socket jack; or the infrared transmitting unit and the infrared receiving unit are arranged on the same side of the socket jack.

Optionally, the infrared emission unit includes an infrared emission tube and a first resistor; the first end of the first resistor is electrically connected with the power supply module, the second end of the first resistor is electrically connected with the anode of the infrared emission tube, and the cathode of the infrared emission tube is electrically connected with the grounding end;

the infrared receiving unit comprises an infrared receiving tube, a first triode, a second resistor and a third resistor; the first end of the second resistor is electrically connected with the power supply module, the second end of the second resistor is respectively electrically connected with the cathode of the infrared receiving tube and the base of the first triode, and the anode of the infrared receiving tube is electrically connected with the ground terminal; the first end of the third resistor is electrically connected with the power supply module, the second end of the third resistor is respectively electrically connected with the collector of the first triode and the relay driving module, and the emitter of the first triode is electrically connected with the grounding end.

Optionally, the socket protection circuit further includes a delay charge-discharge module, and the delay charge-discharge module is arranged in series between the infrared detection module and the relay drive module;

the time-delay charging and discharging module is used for controlling the relay driving module to carry out time-delay opening or time-delay closing according to the detection result of the infrared detection module. Optionally, the time-delay charging and discharging module includes: the second triode, the third triode, the first capacitor and the fourth resistor;

the base electrode of the second triode and the base electrode of the third triode are both electrically connected with the infrared detection module, the emitting electrode of the second triode is electrically connected with the first end of the fourth resistor, and the second end of the fourth resistor is electrically connected with the power supply module; and the collector electrode of the second triode is respectively electrically connected with the anode of the first capacitor, the collector electrode of the third triode and the relay driving module, and the cathode of the first capacitor and the emitter electrode of the third triode are electrically connected with a grounding terminal. Optionally, the relay drive module includes: the fourth triode, the fifth triode, the N-channel MOS tube, the fifth resistor and the sixth resistor;

optionally, the relay drive module includes: the fourth triode, the fifth triode, the N-channel MOS tube, the fifth resistor and the sixth resistor;

a base electrode of the fourth triode is electrically connected with the delay charging and discharging module, and a collector electrode of the fourth triode is electrically connected with a first end of the fifth resistor and a base electrode of the fifth triode respectively;

a collector of the fifth triode is electrically connected with a first end of the sixth resistor and a gate of the N-channel MOS transistor respectively, a second end of the fifth resistor and a second end of the sixth resistor are electrically connected with the power module, and an emitter of the fourth triode, an emitter of the fifth triode and a source of the N-channel MOS transistor are electrically connected with a ground terminal;

the relay comprises a relay coil, a movable contact and a fixed contact, the relay coil is electrically connected between the drain electrode of the N-channel MOS tube and the power module in series, the fixed contact is electrically connected with the live wire, and the movable contact is electrically connected with the live wire end of the plug bush.

Optionally, the relay driver module further comprises a diode;

wherein the diode is arranged in parallel with the relay coil; the anode of the diode is electrically connected with the drain electrode of the N-channel MOS tube, and the cathode of the diode is electrically connected with the power supply module.

Optionally, the power module includes an ac-dc conversion unit and a dc-dc conversion unit;

the input end of the alternating current-direct current conversion unit is electrically connected with a mains supply, the output end of the alternating current-direct current conversion unit is electrically connected with the input end of the direct current-direct current conversion unit, and the output end of the direct current-direct current conversion unit is electrically connected with the infrared detection module and the relay driving module respectively.

Optionally, the power module further includes at least one filtering unit, and an input end of the at least one filtering unit is electrically connected to an output end of the ac-dc converting unit and/or an output end of the dc-dc converting unit.

In a second aspect, the present application provides a socket comprising a socket receptacle, a jacketed live wire end for connection to a live wire, and a socket protection circuit according to any one of the first aspects.

In the embodiment of the application, the socket protection circuit comprises an infrared detection module arranged at a socket hole, a relay electrically connected with a live wire and a plug bush live wire end, a power supply module and a relay driving module; the power supply module is electrically connected with the infrared detection module and the relay driving module respectively, and is used for supplying power to the infrared detection module and the relay driving module; the infrared detection module and the relay are electrically connected with the relay driving module; the infrared detection module is used for detecting whether an electric appliance plug is inserted into the socket jack, and the relay driving module is used for driving the relay to be in a conducting or disconnecting state according to a detection result so as to control the live wire to be conducted or disconnected with the plug bush live wire end. That is to say, the socket protection circuit can control the relay driving module to be started when the infrared detection module detects that an electrical appliance plug is inserted, and further control the relay to be switched to a conducting state; when the infrared detection module does not detect that an electric appliance plug is inserted, the relay drive module is controlled to be closed, and then the relay is controlled to be switched to a disconnection state. Therefore, the socket protection circuit can automatically detect whether an electric appliance plug is inserted, and automatically control the on-off state of the relay according to the detection result so as to realize the function of automatically turning on or off the power supply of the socket, avoid the occurrence of sparks when the socket is used and improve the safety of the socket.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a socket protection circuit according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of an infrared detection module provided in an embodiment of the present application;

fig. 3 is a second schematic structural diagram of a socket protection circuit according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a delayed charge-discharge module according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a relay driving module according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a power module according to an embodiment of the present disclosure;

fig. 7 is a flowchart illustrating a method for controlling spark prevention of a socket protection circuit according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a socket protection circuit according to an embodiment of the present disclosure. As shown in fig. 1, the socket protection circuit is applied to a socket, which includes: the socket jack and the plug sleeve live wire end are used for connecting a live wire; the socket protection circuit comprises an infrared detection module 100 arranged at a socket hole, a relay 200 electrically connected with a live wire and a plug sleeve live wire end, a power supply module 300 and a relay driving module 400;

the power module 300 is electrically connected with the infrared detection module 100 and the relay driving module 400 respectively, and the power module 300 is used for supplying power to the infrared detection module 100 and the relay driving module 400;

infrared detection module 100 and relay 200 all are connected with relay drive module 400 electricity, and infrared detection module 100 is used for detecting whether socket jack department has an electrical apparatus plug to insert, and relay drive module 400 is used for according to infrared detection module 100's testing result, and drive relay 200 is in the on-off state to control to switch on or break off between live wire and the plug bush live wire end.

Specifically, the socket can further comprise a plug bush zero line end and a plug bush ground wire end besides the plug bush ground wire end, wherein the plug bush zero line end is directly electrically connected with a zero line, the plug bush ground wire end is directly electrically connected with a ground wire, and the plug bush ground wire end is electrically connected with a live wire through the relay 200, so that the connection or disconnection of the plug bush ground wire end and the live wire on the socket can be realized by controlling the connection or disconnection state of the relay 200.

In this embodiment, the on or off state of the relay 200 is controlled by the relay driving module 400, and the on or off state of the relay driving module 400 is determined by the result of the infrared detection module 100 detecting whether an electrical plug is inserted into the socket. Therefore, the socket protection circuit can control the relay driving module 400 to be turned on when the infrared detection module 100 detects that an electrical appliance plug is inserted, and further control the relay 200 to be switched to a conducting state; when the infrared detection module 100 does not detect that an appliance plug is inserted, the relay driving module 400 may be controlled to be turned off, and then the relay 200 may be controlled to be switched to the off state. Therefore, the socket protection circuit can automatically detect whether an electric appliance plug is inserted, and automatically control the on-off state of the relay 200 according to the detection result so as to realize the function of automatically turning on or off the power supply of the socket, avoid the occurrence of sparks when the socket is used, and improve the safety of the socket.

Further, referring to fig. 2, fig. 2 is a schematic structural diagram of an infrared detection module provided in the embodiment of the present application. The infrared detection module 100 includes: an infrared transmitting unit 110 and an infrared receiving unit 120;

the infrared transmitting unit 110 and the infrared receiving unit 120 are oppositely arranged at two sides of the socket jack; alternatively, the infrared transmitting unit 110 and the infrared receiving unit 120 are disposed on the same side of the socket jack.

Specifically, the number of the infrared detection modules 100 may be one or multiple, and the application is not particularly limited. When the number of the infrared detection modules 100 is plural, whether an electrical appliance plug is inserted into a plurality of different socket holes can be detected. The infrared detection module 100 may include an infrared emission unit 110 and an infrared reception unit 120. As an embodiment, the infrared transmitting unit 110 and the infrared receiving unit 120 may be disposed opposite to each other at both sides of the socket insertion hole. When no electrical appliance plug is inserted into the socket jack, the infrared ray emitted by the infrared emission unit 110 can be emitted to the infrared receiving unit 120, and the infrared ray received by the infrared receiving unit 120 is stronger; when an electrical appliance plug is inserted into the socket jack, the infrared ray emitted by the infrared emitting unit 110 cannot be emitted to the infrared receiving unit 120, and the infrared ray received by the infrared receiving unit 120 is greatly reduced. As another embodiment, the infrared transmitting unit 110 and the infrared receiving unit 120 may be disposed at the same side of the socket jack. When no electrical appliance plug is inserted into the socket jack, the infrared ray emitted by the infrared emission unit 110 cannot be emitted to the infrared receiving unit 120, and the infrared ray received by the infrared receiving unit 120 is weak; when an electrical appliance plug is inserted into the socket jack, infrared rays emitted by the infrared receiving unit 120 are reflected by the electrical appliance plug, and the infrared rays received by the infrared receiving unit 120 are greatly improved.

In this embodiment, the infrared emitting unit 110 and the infrared receiving unit 120 may be disposed at a socket, and whether an electrical appliance plug is inserted into the socket is determined according to the intensity of the infrared rays received by the infrared receiving unit 120, so as to implement automatic detection of the use state of the socket.

Further, with continued reference to fig. 2, the infrared emission unit 110 includes an infrared emission tube D1 and a first resistor R1; the first end of the first resistor R1 is electrically connected with the power module 300, the second end of the first resistor R1 is electrically connected with the positive electrode of the infrared emission tube D1, and the negative electrode of the infrared emission tube D1 is electrically connected with the ground terminal;

the infrared receiving unit 120 includes an infrared receiving tube D2, a first transistor Q1, a second resistor R2, and a third resistor R3; a first end of the second resistor R2 is electrically connected to the power module 300, a second end of the second resistor R2 is electrically connected to a negative electrode of the infrared receiving tube D2 and a base of the first transistor Q1, and a positive electrode of the infrared receiving tube D2 is electrically connected to a ground terminal; a first end of the third resistor R3 is electrically connected to the power module 300, a second end of the third resistor R3 is electrically connected to a collector of the first transistor Q1 and the relay driver module 400, and an emitter of the first transistor Q1 is electrically connected to a ground terminal.

Specifically, the infrared emission tube D1 is a light emitting body composed of an infrared light emitting diode, a PN junction is made of a material with high infrared radiation efficiency (gallium arsenide (GaAs), gallium aluminum arsenide (GaAlAs), or the like), and infrared light is excited by injecting current to the PN junction under forward bias provided by the power module 300. The emission power of the infrared led is proportional to the magnitude of the forward current, but when the forward current exceeds the maximum rated value, the emission power of the infrared led D3 decreases. Therefore, a first resistor R1 may be serially disposed between the power module 300 and the infrared ray emitting tube D1, and current limiting is performed through the first resistor R1 to ensure the emitting power of the infrared ray emitting tube D1.

The infrared receiving tube D2 can be implemented by a photodiode or a phototransistor. In the present embodiment, a photodiode is employed as the infrared ray receiving tube D2. The tube core of the photodiode is a PN junction with photosensitive characteristic, has unidirectional conductivity, small forward resistance and large reverse resistance, and therefore reverse voltage needs to be applied during operation. When the photodiode is not illuminated, the tube core of the photodiode has very small saturation reverse leakage current, namely dark current, and the photodiode is cut off at the moment; when the photodiode is illuminated, the saturated reverse leakage current can be greatly increased to form a photocurrent, and the magnitude of the photocurrent can be changed along with the change of the incident light intensity.

The second resistor R2 is serially connected between the power module 300 and the ir receiving tube D2 for limiting the current of the branch, so as to satisfy the operating requirement of the ir receiving tube D2. The third resistor R3 is serially connected between the power module 300 and the collector of the first transistor Q1 to form a pull-up resistor for clamping the collector of the first transistor Q1 to a high level.

The first transistor Q1 may be an NPN transistor. When the voltage value of the cathode of the infrared receiving tube D2 reaches the turn-on voltage of the first transistor Q1 as the intensity of incident light increases, the first transistor Q1 is in a turn-on state, the voltage of the collector of the first transistor Q1 changes from a high level to a low level, and a low level signal is output to the relay driving module 400. When the voltage value of the cathode of the infrared receiving tube D2 does not reach the on-state voltage of the first triode Q1, the first triode Q1 is in an off-state, the voltage of the collector of the first triode Q1 is kept at a high level, and a high level signal is output to the relay driving module 400. Therefore, the on state of the first transistor Q1 can be controlled according to the intensity of the light received by the infrared receiving tube D2, and then a corresponding level signal is output to the relay driving module 400, the on or off of the relay driving module 400 is controlled by the level signal, and finally the on or off of the relay 200 is controlled by the on or off of the relay driving module 400.

Further, referring to fig. 3, fig. 3 is a second schematic structural diagram of the socket protection circuit according to the embodiment of the present application. As shown in fig. 3, the socket protection circuit further includes a delay charge-discharge module 500, and the delay charge-discharge module 500 is serially connected between the infrared detection module 100 and the relay driving module 400;

the delay charging and discharging module 500 is configured to control the relay driving module 400 to perform delay on or delay off according to a detection result of the infrared detection module 100.

Thus, in the moment when a plug of an electrical appliance is inserted into or pulled out of the socket jack, the relay driving module 400 does not immediately turn on or turn off the relay driving module 400 when a level signal output by the infrared detection module 100 jumps (i.e., a detection result changes), but supplies power or cuts off power to the electrical appliance after a period of time delay, so that generation of impulse current can be avoided, and safety of the socket is further improved.

Further, referring to fig. 4, the delayed charge-discharge module 500 includes: the circuit comprises a second triode Q2, a third triode Q3, a first capacitor C1 and a fourth resistor R4;

the base electrode of the second triode Q2 and the base electrode of the third triode Q3 are both electrically connected with the infrared detection module 100, the emitter electrode of the second triode Q2 is electrically connected with the first end of the fourth resistor R4, and the second end of the fourth resistor R4 is electrically connected with the power module 300; the collector of the second triode Q2 is electrically connected to the anode of the first capacitor C1, the collector of the third triode Q3 and the relay driving module 400, respectively, and the cathode of the first capacitor C1 and the emitter of the third triode Q3 are both electrically connected to the ground.

In an embodiment, the infrared emitting unit 110 and the infrared receiving unit 120 in the infrared receiving unit 120 are disposed on the same side of the socket jack, that is, when an electrical plug is inserted into the socket jack, the infrared receiving unit 120 can receive the infrared ray reflected by the electrical plug, at this time, the voltage of the negative electrode of the infrared receiving unit 120 is increased, and the first triode Q1 is in a conducting state. When no electrical appliance plug is inserted into the socket jack, the infrared receiving unit 120 cannot receive the infrared ray reflected by the electrical appliance plug, at this time, the voltage of the negative electrode of the infrared receiving unit 120 is reduced, and the first triode Q1 is in a cut-off state.

The second transistor Q2 is a PNP transistor, the third transistor Q3 is an NPN transistor, and the base of the second transistor Q2 and the base of the third transistor Q3 are both electrically connected to the collector of the first transistor Q1, so that when the collector of the first transistor Q1 outputs a low level (i.e., the infrared receiving unit 120 receives a strong infrared light, and the first transistor Q1 is in a conducting state), the second transistor Q2 is in a conducting state, and the third transistor Q3 is in a blocking state, at this time, the first capacitor C1 may be charged by the power module 300, and the voltage of the positive electrode of the first capacitor C1 gradually increases until the first capacitor C1 is charged and then maintains at a high level. In this process, when the first capacitor C1 is charged completely (i.e., the delay time is up), the generated high level may control the relay driver module 400 to turn on, so that the function of turning on the relay driver module 400 with a delay time may be realized. When the collector output of the first transistor Q1 is at a high level (i.e., the infrared receiving unit 120 cannot receive strong infrared light, and the first transistor Q1 is in a cut-off state), the second transistor Q2 is in a cut-off state, and the third transistor Q3 is in a conducting state, at this time, the first capacitor C1 starts to discharge, and the voltage of the positive electrode of the first capacitor C1 gradually decreases until the first capacitor C1 is maintained at a low level after the discharge is completed. In this process, when the first capacitor C1 finishes discharging (i.e., the delay time is up), the low level of the collector of the third transistor Q3 controls the relay driver module 400 to turn off, so that the function of turning off the relay driver module 400 in a delayed manner can be realized.

It should be noted that, in the delay charging and discharging module 500, the delay time is determined by the resistance of the fourth resistor R4 and the capacitance of the first capacitor C1, so that the resistance of the fourth resistor R4 and the capacitance of the first capacitor C1 can be set according to actual requirements to meet different delay requirements. In another embodiment, a current limiting resistor R7 may be connected in series between the base of the second transistor Q2 and the collector of the first transistor Q1, and a current limiting resistor R8 may be connected in series between the base of the third transistor Q3 and the collector of the first transistor Q1, as shown in fig. 4.

Further, referring to fig. 5, fig. 5 is a schematic structural diagram of a relay driving module provided in an embodiment of the present application. The relay driving module 400 includes: the transistor comprises a fourth triode Q4, a fifth triode Q5, an N-channel MOS transistor Q6, a fifth resistor R5 and a sixth resistor R6;

a base electrode of the fourth triode Q4 is electrically connected with the delayed charge-discharge module 500, and a collector electrode of the fourth triode Q4 is electrically connected with a first end of the fifth resistor R5 and a base electrode of the fifth triode Q5 respectively;

a collector of the fifth triode Q5 is electrically connected to a first end of the sixth resistor R6 and a gate of the N-channel MOS transistor Q6, respectively, a second end of the fifth resistor R5 and a second end of the sixth resistor R6 are electrically connected to the power module 300, and an emitter of the fourth triode Q4, an emitter of the fifth triode Q5, and a source of the N-channel MOS transistor Q6 are electrically connected to a ground terminal;

the relay 200 comprises a relay 200 coil, a movable contact and a fixed contact, wherein the relay 200 coil is electrically connected between the drain electrode of the N-channel MOS tube Q6 and the power supply module 300 in series, the fixed contact is electrically connected with a live wire, and the movable contact is electrically connected with a plug sleeve live wire end.

Specifically, the fourth transistor Q4 and the fifth transistor Q5 are NPN transistors. When the first capacitor C1 in the time delay charging/discharging module 500 is in a charging state, the voltage of the base of the fourth transistor Q4 increases with the voltage increase of the first capacitor C1, and when the voltage difference between the base and the emitter of the fourth transistor Q4 reaches the turn-on voltage of the fourth transistor Q4, the fourth transistor Q4 is in a turn-on state, the voltage of the collector of the fourth transistor Q4 is pulled low, so that the fifth transistor Q5 is in a turn-off state, the voltage of the collector of the fifth transistor Q5 is in a high level state, and the N-channel MOS transistor Q6 is turned on. After the N-channel MOS transistor Q6 is turned on, a current flows through the coil of the relay 200, a magnetic field is formed, and the relay 200 is driven to be turned on by the magnetic field. Conversely, when the base of the fourth transistor Q4 is low, the fourth transistor Q4 is off, the voltage at the collector of the fourth transistor Q4 is high, so that the fifth transistor Q5 is turned on, the voltage at the collector of the fifth transistor Q5 is pulled low, and the N-channel MOS transistor Q6 is turned off. After the N-channel MOS transistor Q6 turns off, no current flows through the coil of the relay 200, and the relay 200 is in the off state.

Further, the relay driving module 400 further includes a diode D3;

wherein, the diode D3 is arranged in parallel with the coil of the relay 200; the anode of the diode D3 is electrically connected to the drain of the N-channel MOS transistor Q6, and the cathode of the diode D3 is electrically connected to the power module 300.

In one embodiment, since the diode D3 has a unidirectional conductivity, when the voltage of the drain of the N-channel MOS transistor Q6 is high, a current loop can be formed through the diode D3 and the coil of the relay 200, thereby preventing the N-channel MOS transistor Q6 from being broken down.

Further, referring to fig. 6, fig. 6 is a schematic structural diagram of a power module provided in the embodiment of the present application. The power module 300 includes an ac-dc conversion unit 310 and a dc-dc conversion unit 320;

the input end of the ac-dc conversion unit 310 is electrically connected to the mains supply, the output end of the ac-dc conversion unit 310 is electrically connected to the input end of the dc-dc conversion unit 320, and the output end of the dc-dc conversion unit 320 is electrically connected to the infrared detection module 100 and the relay driving module 400, respectively.

Specifically, the ac-dc conversion unit 310 may be implemented by any chip having an ac-dc conversion function, including but not limited to a WD5208 chip, a PN8173 chip, and the like, and may convert ac power into dc power. The dc-dc conversion unit 320 may be implemented by any chip having a dc-dc conversion function, including but not limited to a MC34063A chip, a TPS54331DR chip, and the like, and may convert a voltage value of a dc current. The power module 300 is used for converting 220V commercial power to obtain a dc voltage required for the infrared detection module 100 and the relay driving module 400 to operate.

With continued reference to fig. 6, the power module 300 further includes at least one filtering unit 330, and an input terminal of the at least one filtering unit 330 is electrically connected to an output terminal of the ac-dc converting unit 310 and/or an output terminal of the dc-dc converting unit 320. The power module 300 is connected in parallel to the live wire and the zero wire of the commercial power to obtain a power supply, and rectifies and filters the input commercial power current through the filtering unit 330, and transforms the voltage, and/or rectifies and filters the current transformed by the dc-dc conversion unit 320 through the filtering unit 330, and finally obtains a stable dc voltage to supply power to the infrared detection module 100, the relay driving module 400, the delay charging and discharging module 500, and the relay 200.

In addition, the embodiment of the present application further provides a socket, which includes a socket jack, a sleeve live wire end for connecting live wire, and the socket protection circuit provided in any one of the foregoing embodiments. Since the socket can realize the embodiments of the socket protection circuit and achieve the same technical effects, the details are not repeated herein.

In practical application, referring to fig. 7, fig. 7 is a schematic flow chart of a method for controlling spark prevention of a socket protection circuit according to an embodiment of the present application. The method for controlling the spark prevention of the socket protection circuit may include the steps of:

step 701, detecting the insertion state of an electric appliance plug through an infrared detection module 100 under the condition that a socket is communicated with mains supply;

step 702, judging whether an electrical appliance plug is inserted into a socket jack;

in case the electrical appliance plug is inserted into the socket jack, performing step 703; in case the electrical appliance plug is not inserted into the socket jack, executing step 706;

step 703, the delayed charging and discharging module 500 charges the first capacitor C1;

step 704, when the charging of the first capacitor C1 is completed (i.e., the delay time is up), controlling the relay driving module 400 to be turned on, and controlling the relay 200 to be turned on by the relay driving module 400;

step 705, the socket plug fire wire end is connected with the fire wire, and the electrical appliance power supply is connected.

Step 706, the delayed charging and discharging module 500 discharges the first capacitor C1;

step 707, controlling the relay driving module 400 to be turned off and controlling the relay 200 to be turned off through the relay driving module 400 under the condition that the first capacitor C1 is charged to the voltage threshold value of the relay driving module 400 to be turned off;

and 708, disconnecting the live wire end of the socket plug sleeve from the live wire, and disconnecting the power supply of the electric appliance.

Therefore, the insertion state of the power plug can be automatically detected through the infrared detection module 100, the on and off of the relay are controlled, the function of automatically turning on or off the power supply of the socket is realized, and the on and off time of the power supply can be prolonged through the charge and discharge delay circuit when the power supply is automatically turned on or off, so that the occurrence of impact current is prevented, and the safety of the socket is further improved.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.