Electric leakage detection interruption circuit, electric leakage detection interrupter and electrical equipment

Abstract

The invention discloses an electric leakage detection interruption circuit, an electric leakage detection interrupter and electrical equipment, the circuit is suitable for being connected between a power supply input end and a load, and the circuit comprises a switch unit used for controlling whether a power supply is connected or not; the switch driving unit is used for controlling the on-off of the switch unit; the shielding unit wraps the load power supply line so as to carry out electric leakage detection on the load power supply line; the detection unit comprises a power supply voltage stabilizing chip or a photoelectric coupler, is respectively connected with the shielding unit and the switch driving unit, and is used for increasing the voltage between two detection pins of the power supply voltage stabilizing chip or the photoelectric coupler to a voltage threshold value when the open circuit of the shielding unit is detected, so that the power supply voltage stabilizing chip or the photoelectric coupler is conducted; therefore, the switch driving unit is triggered to control the switch unit to be switched off so as to cut off power supply access. The circuit can cut off the access of a power supply when the conductor shielding layer is open-circuited, so that the danger caused by the fact that electric leakage cannot be detected in time can be prevented, and the protection and safety effects are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of leakage detection, and in particular to a leakage detection interruption circuit, a leakage detection interrupter and electrical equipment. Background Art

[0002] At present, leakage protection technology generally detects whether leakage occurs and cuts off the power supply to achieve protection when leakage occurs. However, when the device used for leakage detection is damaged and cannot detect whether leakage occurs, if leakage occurs, the above technology will not detect leakage and will not cut off the power supply, causing safety hazards. Summary of the invention

[0003] One object of the present invention is to provide a leakage detection interrupt circuit, a leakage detection interrupter and an electrical device, so as to cut off the power supply in time when a shielding unit used for leakage detection is open circuit, so as to play a protective and safety role.

[0004] To achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention proposes a leakage detection interrupt circuit, which is suitable for being connected between a power input terminal and a load, and includes: a switch unit, used to control whether the power supply at the power input terminal is connected; a switch drive unit, used to control the on and off of the switch unit; a shielding unit, used to wrap around the load power supply line to perform leakage detection on the load power supply line; a detection unit, including a power supply voltage regulator chip or a photoelectric coupler, and the detection unit is respectively connected to the shielding unit and the switch drive unit, and is used to increase the voltage between the two detection pins of the power supply voltage regulator chip or the photoelectric coupling device to a voltage threshold when it is detected that the shielding unit is open-circuited, so that the power supply voltage regulator chip or the photoelectric coupling device is turned on, thereby triggering the switch drive unit to control the switch unit to disconnect, so as to cut off the access to the power supply.

[0005] In addition, the leakage detection interruption circuit of the above embodiment of the present invention may also have the following additional technical features:

[0006] According to one embodiment of the present invention, the detection unit includes a first detection end and a second detection end, and the shielding unit includes a conductor shielding layer, the conductor shielding layer is used to wrap the live wire connection line and the neutral wire connection line in the load power supply line, and is respectively connected to the first detection end and the second detection end, wherein when the connection between the first detection end and the second detection end is disconnected, the shielding unit is open-circuited.

[0007] According to an embodiment of the present invention, the detection unit is further configured to trigger the switch driving unit to control the switch unit to disconnect, so as to cut off access to the power supply, when detecting that a leakage current flows through the shielding unit.

[0008] According to one embodiment of the present invention, the switch unit includes: a trip coil switch, a first diode, a second diode and a first switch tube; the trip coil switch includes a first contact, a second contact and a winding, the first contact is used to connect the neutral line of the power supply, the second contact is connected to the neutral line connection line in the load power supply line, the first end of the winding is connected to the live line connection line in the load power supply line, the second end of the winding is connected to the cathode of the second diode to form a first node, and the first node is connected to the third detection end of the detection unit, wherein the winding is used to trigger the on and off between the first contact and the second contact; the cathode of the first diode is connected to the neutral line connection line; the anode of the second diode is connected to the anode of the first diode to form a second node, and the second node is connected to the first end of the switch drive unit; the first end of the first switch tube is connected to the second node, the second end of the first switch tube is connected to the first node, and the control end of the first switch tube is connected to the second end of the switch drive unit.

[0009] According to one embodiment of the present invention, the switch driving unit includes: a first capacitor, a third resistor, a fourth resistor and an eighth resistor; the first end of the first capacitor serves as the first end of the switch driving unit, and the second end of the first capacitor serves as the second end of the switch driving unit; the fourth resistor is connected in parallel with the first capacitor; the first end of the third resistor is connected to the second end of the first capacitor, and the second end of the third resistor is connected to the first detection end; the first end of the eighth resistor is connected to the first end of the first capacitor, and the second end of the eighth resistor is connected to the second end of the third resistor.

[0010] According to one embodiment of the present invention, when the detection unit includes the photoelectric coupler, it also includes a fifth resistor, a sixth resistor and a seventh resistor. The photoelectric coupler has four pins, namely, a light-emitting diode cathode, a light-emitting diode anode, a phototransistor emitter, and a phototransistor collector. The phototransistor emitter is connected to the second end of the switch drive unit, and the phototransistor collector is connected to the first end of the fifth resistor. The light-emitting diode cathode serves as the first detection end, and the light-emitting diode anode serves as the second detection end, and the light-emitting diode cathode and the light-emitting diode anode are the two detection pins. The second end of the fifth resistor serves as the third detection end of the detection unit, the first end of the sixth resistor is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor is connected to the second detection end, the first end of the seventh resistor is connected to the second detection end, and the second end of the seventh resistor is connected to the first detection end.

[0011] According to one embodiment of the present invention, when the detection unit includes the power supply voltage stabilizing chip, it also includes a fifth resistor, a sixth resistor and a seventh resistor. The power supply voltage stabilizing chip has three pins, namely a cathode, an anode and a reference voltage terminal. The anode of the power supply voltage stabilizing chip serves as the first detection terminal, the reference voltage terminal of the power supply voltage stabilizing chip serves as the second detection terminal, and the anode and the reference voltage terminal of the power supply voltage stabilizing chip serve as the two detection pins. The first end of the fifth resistor is connected to the cathode of the power supply voltage stabilizing chip, the second end of the fifth resistor serves as the third detection terminal of the detection unit, the first end of the sixth resistor is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor is connected to the second detection terminal, the first end of the seventh resistor is connected to the second detection terminal, and the second end of the seventh resistor is connected to the first detection terminal.

[0012] According to one embodiment of the present invention, the circuit further includes: a test unit, the test unit including a test switch, the test switch being connected in parallel with the sixth resistor; wherein the detection unit is also used to trigger the switch drive unit to control the switch unit to disconnect when it detects that the test switch is pressed, so as to cut off access to the power supply.

[0013] To achieve the above object, a second embodiment of the present invention provides a leakage detection interrupter, including the above leakage detection interrupt circuit.

[0014] To achieve the above object, a third aspect of the present invention provides an electrical device, including the above leakage detection interrupter.

[0015] The leakage detection interrupt circuit, leakage detection interrupter and electrical equipment of the embodiments of the present invention can control the switch unit to disconnect through the switch driving unit to cut off the power supply when the detection unit detects that the shielding unit is open, thereby preventing danger caused by failure to detect leakage in time, and playing a protective and safety role. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the structure of a leakage detection interrupt circuit in some embodiments of the present invention;

[0017] Figure 2 is a schematic diagram of a plug using a leakage detection interruption circuit according to an embodiment of the present invention;

[0018] FIG3( a ) is a schematic diagram of a plug connection line according to a first embodiment of the present invention;

[0019] FIG3( b ) is a schematic diagram of a plug connection line according to a second embodiment of the present invention;

[0020] Figure 4is a topological diagram of a leakage detection interrupt circuit according to a first specific embodiment of the present invention;

[0021] Figure 5 is a topological diagram of a leakage detection interrupt circuit according to a second specific embodiment of the present invention;

[0022] Figure 6 is a topological diagram of a leakage detection interrupt circuit according to a third specific embodiment of the present invention;

[0023] Figure 7 is a structural block diagram of a leakage detection interrupter according to an embodiment of the present invention;

[0024] Figure 8 It is a structural block diagram of an electrical device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0026] The following describes a leakage detection interrupt circuit, a leakage detection interrupter, and an electrical device according to embodiments of the present invention with reference to the accompanying drawings.

[0027] Figure 1 It is a schematic diagram of the structure of the leakage detection interrupt circuit of the embodiment of the invention.

[0028] like Figure 1 As shown, the leakage detection interruption circuit 100 is suitable for being connected between a power input terminal (such as an AC input terminal) and a load LOAD (such as an electrical device in an air conditioner). The circuit 100 comprises: a switch unit 10, a switch driving unit 11, a shielding unit 12 and a detection unit 13.

[0029] See also Figure 1 The switch unit 10 is used to control whether the power supply (such as AC power supply) at the power input end is connected; the switch driving unit 11 is used to control the on and off of the switch unit 10; the shielding unit 12 is used to wrap around the load power supply line to perform leakage detection on the load power supply line; the detection unit 13 includes a power supply voltage regulator chip IC3 or a photocoupler IC2, and is connected to the shielding unit 12 and the switch driving unit 11 respectively, and is used to increase the voltage between the two detection pins of the power supply voltage regulator chip IC3 or the photocoupler IC2 to a voltage threshold when it is detected that the shielding unit 12 is open-circuited, so that the power supply voltage regulator chip IC3 or the photocoupler IC2 is turned on, thereby triggering the switch driving unit 11 to control the switch unit 10 to disconnect, so as to cut off the access to the power supply AC.

[0030] The voltage threshold can be calibrated according to actual circuit requirements, and the power supply voltage regulator chip IC3 and the photocoupler IC2 can be selected according to the voltage threshold.

[0031] In some embodiments, the detection unit 13 is also used to trigger the switch driving unit 11 to control the switch unit 10 to disconnect when it detects leakage current flowing through the shielding unit 12, so as to cut off the access of the power supply AC, thereby achieving a protective effect when leakage occurs.

[0032] Specifically, see Figure 1 , the load power supply line includes a live wire connection line and a neutral wire connection line. For a three-phase line, the load power supply line may also include a ground wire connection line. The switch unit 10 is used to establish a connection between the load power supply line and the live wire L and the neutral wire N of the power supply AC, wherein the live wire connection line is used to connect the live wire L of the power supply AC, the neutral wire connection line is used to connect the neutral wire N of the power supply AC, and the ground wire connection line is used to connect the ground wire PE of the power supply AC. The detection unit 13 is respectively connected to the shielding unit 12 and the switch driving unit 11, and is used to increase the voltage between the two detection pins of the power supply voltage regulator chip IC3 or the photocoupler IC2 to a voltage threshold when it is detected that the shielding unit 12 is open-circuited, so that the power supply voltage regulator chip IC3 or the photocoupler IC2 is turned on, thereby triggering the switch driving unit 11 to control the switch unit 10 to disconnect, so as to cut off the access to the power supply AC. In this way, it is possible to prevent the danger caused by the failure to detect leakage in time due to the open circuit of the shielding unit 12, thereby playing a protective and safety role.

[0033] In some embodiments, the leakage detection interruption circuit 100 can be used in a plug, such as Figure 2 As shown in FIG. 3 , the plug may be a plug used in conjunction with electrical appliances such as air conditioners, rice cookers, refrigerators, induction cookers, humidifiers, etc. The plug may include three pins, which are respectively connected to the live wire connection line, the neutral wire connection line and the ground wire connection line of the load power supply line, and are used to correspond to the live wire L, the neutral wire N and the ground wire PE of the power supply AC, as shown in FIG. 3 (a) and FIG. 3 (b).

[0034] See also Figure 1 3(a) and 3(b), the detection unit 13 may include a first detection end and a second detection end, and the shielding unit 12 may include a conductor shielding layer AB, the conductor shielding layer AB is used to wrap the live wire and the neutral wire in the load power supply line, and is respectively connected to the first detection end and the second detection end, wherein when the connection between the first detection end and the second detection end is disconnected, the shielding unit 12 is open-circuited.

[0035] In some embodiments, see Figure 1, Figure 3(a), Figure 3(b), one of the first detection terminal and the second detection terminal is connected to the conductor shielding layer AB through the wire CD. For ease of description, the following is an example of the connection between the second detection terminal and the wire CD. Referring to Figure 3(a) and Figure 3(b), the A terminal is close to the input terminal and connected to the first detection terminal, the B terminal is close to the output terminal, the C terminal is close to the input terminal and connected to the second detection terminal, the D terminal is close to the output terminal, and the B terminal of the conductor shielding layer AB and the D terminal of the wire CD are connected to form a path.

[0036] Since the live wire, the neutral wire and the ground wire are all conductors (such as copper wires), see FIG3 (a) and FIG3 (b), the live wire, the neutral wire and the ground wire can be respectively wrapped with an insulating layer (which can be made of insulating materials such as rubber and plastic), and the insulating materials of the live wire and the neutral wire are wrapped with a conductor shielding layer AB for leakage detection. To further ensure safety, the three wires together with their respective insulating layers and the conductor shielding layer AB can also be encapsulated by a sheath (which can be made of insulating materials such as rubber and plastic).

[0037] The length of the conductor shielding layer AB can be set as required, such as the conductor shielding layer AB is wrapped around the insulation layer surface of part of the neutral wire connecting line and the insulation layer surface of part of the live wire connecting line.

[0038] When using the above plug, the detection unit 13 can detect whether there is leakage current flowing through the conductor shielding layer AB, and can also detect whether the conductor shielding layer AB is damaged and disconnected. If any of the above situations occurs, the switch driving unit 11 is triggered to control the switch unit 10 to disconnect, so as to cut off the access to the power supply AC and achieve protection. In this way, not only can the access to the power supply AC be cut off when leakage is detected, but also when the conductor shielding layer AB is damaged and the leakage cannot be detected in time, the access to the power supply AC can be cut off, thereby improving the safety and reliability of the operation of the electrical equipment.

[0039] In some examples, see FIG. 3( a ), the conductor shielding layer AB wraps the live wire and the neutral wire together in the same columnar structure, and a filler may be filled between the inner surface of the columnar structure and the insulating layer of the live wire and the insulating layer of the neutral wire.

[0040] In this example, referring to FIG. 3(a), the outer surface of the live wire connection line L1 is provided with a first insulating layer J1, the outer surface of the neutral wire connection line N1 is provided with a second insulating layer J2, the outer surface of the ground wire connection line PE1 in the load power supply line is provided with a third insulating layer J3, the outer surface of the conductor CD is provided with a fourth insulating layer J4, the conductor shielding layer AB is wrapped around the outer surface of part of the first insulating layer J1 and part of the second insulating layer J2, and a filler (not shown in the figure) can be used to fill the conductor shielding layer AB and the first insulating layer J1 and the second insulating layer J2, and the outer surface of the conductor shielding layer AB, the outer surface of the third insulating layer J3 and the outer surface of the fourth insulating layer J4 are provided with a fifth insulating layer J5. Among them, the fifth insulating layer J5 and the conductor shielding layer AB, the third insulating layer J3 and the fourth insulating layer J4 can be filled with a filler TC.

[0041] In other examples, see FIG3(b), the conductor shielding layer AB has a first part and a second part, the first part is configured to wrap the live wire L1, and the second part is configured to wrap the neutral wire N1, that is, the conductor shielding layer AB wraps the live wire and the neutral wire in two columnar structures respectively. The wrapping method can be: the starting end is at the intersection of the neutral wire and the live wire, and the live wire is wrapped around the live wire for one circle and then the neutral wire is wrapped around, so that the conductor shielding layer AB completely covers the neutral wire and the live wire. Of course, this wrapping method is relatively rare, and it is also possible to wrap around the neutral wire or the live wire for multiple circles, and at this time, the starting end or the ending end is not limited to the intersection.

[0042] In this example, referring to FIG. 3(b), the outer surface of the live wire connection line L1 is provided with a first insulating layer J1, the outer surface of the neutral wire connection line N1 is provided with a second insulating layer J2, the outer surface of the ground wire connection line PE1 in the load power supply line is provided with a third insulating layer J3, the outer surface of the conductor CD is provided with a fourth insulating layer J4, the conductor shielding layer AB is respectively wrapped around the outer surface of part of the first insulating layer J1 and the outer surface of part of the second insulating layer J2, and the outer surface of the conductor shielding layer AB, the outer surface of the third insulating layer J3 and the outer surface of the fourth insulating layer J4 are provided with a fifth insulating layer J5. Among them, the fifth insulating layer J5 and the conductor shielding layer AB, the third insulating layer J3 and the fourth insulating layer J4 can be filled with filler TC.

[0043] In an embodiment of the present invention, the material used for the conductor shielding layer AB may include metal material and semiconductor material, the metal material includes at least one of gold, silver, copper, iron, aluminum, and alloy, and the semiconductor material includes at least one of carbon, silicon, germanium, and graphene. The form of the conductor shielding layer includes at least one of mesh, sheet, and strip, and the shape includes at least one of round, square, elliptical, polygonal, and irregular.

[0044] The connection method between the conductor shielding layer AB and the conductor CD may include at least one of mechanical winding connection, welding connection, and mechanical locking connection. When the second detection end is connected to the conductor CD, the connection method between the conductor CD and the second detection end, and the connection method between the conductor shielding layer AB and the first detection end may include at least one of welding connection, pin connection, and locking piece connection.

[0045] In some embodiments, Figure 4 , Figure 5 , Figure 6 As shown, the switch unit 10 includes: a trip coil switch RY, a first diode D1, a second diode D2 and a first switch tube Q1.

[0046] See also Figure 4 , Figure 5 , Figure 6 The trip coil switch RY includes a first contact 1, a second contact 2 and a winding, wherein the first contact 1 is used to connect the neutral line of the power supply, the second contact 2 is connected to the neutral line connection line in the load power supply line, the first end 5 of the winding is connected to the live line connection line in the load power supply line, the second end 6 of the winding is connected to the cathode of the second diode D2 to form a first node, and the first node is connected to the third detection end of the detection unit 13, wherein the winding is used to trigger the on-off between the first contact 1 and the second contact 2. The cathode of the first diode D1 is connected to the neutral line connection line; the anode of the second diode D2 is connected to the anode of the first diode D1 to form a second node, and the second node is connected to the first end of the switch drive unit 11. The first end of the first switch tube Q1 is connected to the second node, the second end of the first switch tube Q1 is connected to the first node, and the control end of the first switch tube Q1 is connected to the second end of the switch drive unit 11.

[0047] In this embodiment, the first contact 1 and the second contact 2 can be disconnected by the winding trigger, so as to cut off the access of the power supply AC. Specifically, the winding of the tripping coil switch RY is energized to generate magnetic force, the tripping coil switch RY is attracted by the magnetic force, the first contact 1 and the second contact 2 are disconnected, and the access of the neutral line of the power supply AC is cut off; accordingly, the winding of the tripping coil switch RY loses power, the tripping coil switch RY is not attracted by the magnetic force, the first contact 1 and the second contact 2 are connected, and the access of the neutral line of the power supply AC is connected.

[0048] As some examples, the first switch tube Q1 can be a triode or a thyristor ( Figure 4 , Figure 5 , Figure 6The thyristor is shown as an example. The thyristor is a component composed of four layers of PNPN semiconductors, with three electrodes: anode, cathode and control electrode. Its characteristics are: when the anode is connected to a reverse voltage, or the anode is connected to a forward voltage but the control electrode is not connected to a voltage, it will not conduct, and when the anode and the control electrode are connected to a forward voltage at the same time, it will become conductive. Once it is conductive, the control voltage loses its control effect on it, and it will always be in the conductive state regardless of whether there is a control voltage or the polarity of the control voltage.

[0049] Optionally, to further improve the reliability of cutting off the AC power supply, see Figure 4 , Figure 5 , Figure 6 The trip coil switch RY may also include a third contact 3 and a fourth contact 4, the third contact 3 is used to connect the live wire L of the power supply AC, and the fourth contact 4 is connected to one end of the live wire connecting line, wherein the winding is also used to trigger the on and off of the third contact 3 and the fourth contact 4.

[0050] Specifically, the winding of the trip coil switch RY is energized to generate magnetic force, the trip coil switch RY is sucked open by the magnetic force, and the third contact 3 and the fourth contact 4 are disconnected, thereby cutting off the access to the AC live wire of the power supply; accordingly, the winding of the trip coil switch RY loses power, the trip coil switch RY is not sucked open by the magnetic force, the third contact 3 and the fourth contact 4 are connected, and the access to the AC live wire L of the power supply is achieved.

[0051] Thus, the winding triggers the first contact 1 to be disconnected from the second contact 2, and can also trigger the third contact 3 and the fourth contact 4, thereby improving the reliability of cutting off the power supply AC access.

[0052] In some embodiments, Figure 5 , Figure 6 As shown, the switch unit 10 further includes: a second varistor ZR2; and a second diode D2 connected in parallel with the second varistor ZR2.

[0053] Specifically, the varistor is a resistor device with nonlinear volt-ampere characteristics, which is mainly used to clamp the voltage when the circuit is subjected to overvoltage, absorb excess current to protect sensitive devices. The second varistor ZR2 can be short-circuited when the voltage at both ends of it changes sharply, so as to melt the current fuse (not shown in the figure) and play a protective role.

[0054] In some embodiments, Figure 5 , Figure 6As shown, the leakage detection interrupt circuit 100 may also include: an indication unit 15, including a first resistor R1, a second resistor R2 and a light emitting diode LED1, the first resistor R1, the second resistor R2 and the light emitting diode LED1 are connected in series between the first node and the anode of the first diode D1, wherein the anode of the light emitting diode LED1 is closer to the first node than the cathode of the light emitting diode LED1.

[0055] in, Figure 5 , Figure 6 The series connection of the first resistor R1, the second resistor R2 and the light-emitting diode LED1 shown is only an example. The second resistor R2, the first resistor R1 and the light-emitting diode LED1 can also be connected in series in sequence, the second resistor R2, the light-emitting diode LED1 and the first resistor R1 can be connected in series in sequence, the first resistor R1, the light-emitting diode LED1 and the second resistor R2 can be connected in series in sequence, the light-emitting diode LED1, the second resistor R2 and the first resistor R1 can be connected in series in sequence, the light-emitting diode LED1, the first resistor R1 and the second resistor R2 can be connected in series in sequence, and so on.

[0056] Specifically, when current flows through the light emitting diode LED1, the light emitting diode LED1 can be illuminated. Therefore, the direction of the current flow or the current state of the leakage detection interruption circuit 100 can be determined by whether the light emitting diode LED1 emits light. The light color of the light emitting diode LED1 can be calibrated as needed, such as red, green, etc.

[0057] In some embodiments, Figure 4 , Figure 5 , Figure 6 As shown, the switch driving unit 11 includes: a first capacitor C1, a third resistor R3, a fourth resistor R4 and an eighth resistor R8.

[0058] See also Figure 4 , Figure 5 , Figure 6 , the first end of the first capacitor C1 serves as the first end of the switch driving unit 11, and the second end of the first capacitor C1 serves as the second end of the switch driving unit 11; the fourth resistor R4 is connected to the first capacitor C1 in parallel; the first end of the third resistor R3 is connected to the second end of the first capacitor C1, and the second end of the third resistor R3 is connected to the first detection end; the first end of the eighth resistor R8 is connected to the first end of the first capacitor C1, and the second end of the eighth resistor R8 is connected to the second end of the third resistor R3.

[0059] Specifically, the first capacitor C1 can stabilize the control electrode and cathode voltage of the first switch tube Q1, and the third resistor R3, the fourth resistor R4 and the eighth resistor R8 can play a voltage dividing role. The specific resistance values ​​can be set as needed.

[0060] In some embodiments, Figure 5 , Figure 6 As shown, the leakage detection interrupt circuit 100 also includes: a lightning protection unit 16, including a first varistor ZR1, one end of the first varistor ZR1 is connected to the neutral line connection line in the load power supply line, and the other end of the first varistor ZR1 is connected to the live line connection line in the load power supply line.

[0061] When the grid voltage at both ends of the first varistor ZR1 changes sharply, the resistance will quickly decrease to nearly 0 ohm, short-circuiting the grid voltage of 220V and blowing out the corresponding fuse (not shown in the figure), thereby playing a role of insurance.

[0062] It should be noted that when selecting the first varistor ZR1 for lightning protection, you need to pay attention to the following:

[0063] ①The working environment temperature of the first varistor ZR1 should be within the range specified by the technical conditions;

[0064] ②The first varistor ZR1 should not be installed close to heat-generating or flammable components, with a gap greater than 3 mm to avoid damaging the components;

[0065] ③The surge peak current passing through the first varistor ZR1 should not exceed the "peak current" listed in the technical parameter table of the lightning protection varistor.

[0066] In some embodiments, Figure 5 As shown, when the detection unit 13 includes the photocoupler IC2, the detection unit 13 also includes a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7. The photocoupler IC2 has four pins, which are a cathode of a light emitting diode, an anode of a light emitting diode, an emitter of a phototransistor and a collector of a phototransistor. The emitter of the phototransistor is connected to the second end of the switch driving unit 11, the collector of the phototransistor is connected to the first end of the fifth resistor R5, the cathode of the light emitting diode serves as the first detection end, the anode of the light emitting diode serves as the second detection end, and the cathode of the light emitting diode and the anode of the light emitting diode are two detection pins, the second end of the fifth resistor R5 serves as the third detection end of the detection unit 13, the first end of the sixth resistor R6 is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor R6 is connected to the second detection end, the first end of the seventh resistor R7 is connected to the second detection end, and the second end of the seventh resistor R7 is connected to the first detection end.

[0067] In some embodiments, Figure 6As shown, when the detection unit 13 includes a power supply voltage stabilizing chip IC3, the detection unit 13 includes a fifth resistor R5, a sixth resistor R6 and a seventh resistor R7. The power supply voltage stabilizing chip IC3 has three pins, namely a cathode, an anode and a reference voltage terminal. The anode of the power supply voltage stabilizing chip IC3 serves as a first detection terminal, the reference voltage terminal of the power supply voltage stabilizing chip IC3 serves as a second detection terminal, and the anode and the reference voltage terminal of the power supply voltage stabilizing chip IC3 are two detection pins. The first end of the fifth resistor R5 is connected to the cathode of the power supply voltage stabilizing chip IC3, the second end of the fifth resistor R5 serves as the third detection terminal of the detection unit 13, the first end of the sixth resistor R6 is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor R6 is connected to the second detection terminal, the first end of the seventh resistor R7 is connected to the second detection terminal, and the second end of the seventh resistor R7 is connected to the first detection terminal.

[0068] exist Figure 5 , Figure 6 In the illustrated embodiment, the resistance values ​​of the fifth resistor R5 , the sixth resistor R6 , and the seventh resistor R7 can be set as required.

[0069] In some embodiments, Figure 5 , Figure 6 As shown, the leakage detection interruption circuit 100 further includes: a testing unit 14 .

[0070] See also Figure 5 , Figure 6 The testing unit 14 includes a testing switch TEST, and the testing switch TEST is connected in parallel with the sixth resistor R6.

[0071] The test switch TEST can be set on the plug and the setting position can be as follows: Figure 2 Specifically, when using the plug, the test switch TEST can be pressed to trigger the switch drive unit 11 to control the switch unit 10 to disconnect, thereby cutting off the power supply AC, thereby preventing leakage and ensuring that the user will not be in danger of electric shock.

[0072] The following are Figure 5 , Figure 6 Taking the embodiment shown as an example, the working principle of the leakage detection interruption circuit 100 of the embodiment of the present invention is described:

[0073] See also Figure 5 , Figure 6When the detection unit 13 detects that there is leakage current from the live wire L to the conductor shielding layer AB, the live wire L, the conductor shielding layer AB, the third resistor R3, the fourth resistor R4, the first diode D1 and the neutral wire N form a current loop, the control electrode voltage of the first switch tube Q1 increases, triggering the first switch tube Q1 to turn on, the live wire L, the winding of the tripping coil switch RY, the first switch tube Q1, and the first diode D1 form a strong current loop, the winding of the tripping coil switch RY generates a strong magnetic force, the tripping coil switch RY is sucked away by the magnetic force, and the power supply is cut off.

[0074] See also Figure 5 , Figure 6 When the detection unit 13 detects that there is leakage current from the neutral line N to the conductor shielding layer AB, the neutral line N, the conductor shielding layer AB, the third resistor R3, the fourth resistor R4, the second diode D2, the winding of the tripping coil switch RY and the live line L form a current loop, and the control electrode voltage of the first switch tube Q1 increases, triggering the first switch tube Q1 to turn on, and the live line L, the winding of the tripping coil switch RY, the first switch tube Q1, and the first diode D1 form a strong current loop, and the winding of the tripping coil switch RY generates a strong magnetic force, and the tripping coil switch RY is sucked away by the magnetic force, and the power supply is cut off.

[0075] See also Figure 5 When the detection unit 13 detects that the conductor shielding layer AB is open, the live wire L, the sixth resistor R6, the seventh resistor R7, the eighth resistor R8, the first diode D1, and the neutral wire N form a current loop, and the seventh resistor R7 divides the voltage, so that the light-emitting diode of the photocoupler IC2 lights up, and the phototransistor of the photocoupler IC2 is turned on. The live wire L, the winding of the trip coil switch RY, the fifth resistor R5, the phototransistor of the photocoupler IC2, the fourth resistor R4, the first diode D1 and the neutral wire N form a current loop, so that the voltage across the fourth resistor R4 reaches the triggering pole voltage of the first switch tube Q1, and the control pole voltage of the first switch tube Q1 increases, triggering the first switch tube Q1 to turn on, and the live wire L, the winding of the trip coil switch RY, the first switch tube Q1, the first diode D1 and the neutral wire N form a strong current loop, and the winding of the trip coil switch RY generates a strong magnetic force, and the trip coil switch RY is attracted by the magnetic force, and the power supply is cut off.

[0076] See also Figure 6When it is detected that the conductor shielding layer AB is open, the live wire L, the sixth resistor R6, the seventh resistor R7, the eighth resistor R8, the first diode D1 and the neutral wire N form a current loop, the seventh resistor R7 divides the voltage, and the voltage across the seventh resistor R7 is greater than the reference voltage Vef of the power supply voltage regulator chip IC3, so that the power supply voltage regulator chip IC3 is turned on, and the live wire L, the winding of the tripping coil switch RY, the fifth resistor R5, the power supply voltage regulator chip IC3, the third resistor R3, the fourth resistor R4, the first diode D1 and the neutral wire N form a current loop, so that the voltage across the fourth resistor R4 reaches the triggering electrode voltage of the first switch tube Q1, and the control electrode voltage of the first switch tube Q1 increases, triggering the first switch tube Q1 to turn on, and the live wire L, the winding of the tripping coil switch RY, the first switch tube Q1, the first diode D1 and the neutral wire N form a strong current loop, and the winding of the tripping coil switch RY generates a strong magnetic force, and the tripping coil switch RY is attracted by the magnetic force, and the power supply is cut off.

[0077] See also Figure 5 , Figure 6 When the test switch TEST is pressed, the live wire L, the test switch TEST, the wire CD, the conductor shielding layer AB, the third resistor R3, the fourth resistor R4, the first diode D1 and the neutral wire N form a current loop, the control electrode voltage of the first switch tube Q1 increases, triggering the first switch tube Q1 to turn on, the live wire L, the winding of the trip coil switch RY, the first switch tube Q1, the first diode D1 and the neutral wire N form a strong current loop, the winding of the trip coil switch RY generates a strong magnetic force, the trip coil switch RY is sucked away by the magnetic force, and the power supply is cut off.

[0078] The leakage detection interrupt circuit of the embodiment of the present invention can not only control the switch unit to be disconnected and cut off the access of the power supply through the switch driving unit when it is detected that there is leakage current in the live wire L or the neutral wire N to the shielding unit or the test switch is pressed, thereby realizing leakage protection and ensuring the safety of the plug being inserted into the power supply; it can also control the switch unit to be disconnected and cut off the power supply through the switch driving unit when the shielding unit is open-circuited, thereby solving the problem of danger caused by the inability to detect the leakage current in time due to the damage and open-circuit of the conductor shielding layer, and can better play a protective and safety role.

[0079] Figure 7 It is a structural block diagram of a leakage detection interrupter according to an embodiment of the present invention.

[0080] like Figure 7 As shown, the leakage detection interrupter 300 includes the leakage detection interrupter circuit 100 described above. The leakage detection interrupter 300 may be Figure 2 The three-phase plug shown can also be a two-phase plug, which can be applied according to actual needs.

[0081] The leakage detection interrupter of the embodiment of the present invention, through the above-mentioned leakage detection interrupt circuit, can not only control the switch unit to be disconnected and cut off the access of the power supply through the switch driving unit when it is detected that there is leakage current in the live wire L or the neutral wire N to the shielding unit or the test switch is pressed, thereby realizing leakage protection and ensuring the safety of the plug being inserted into the power supply; it can also control the switch unit to be disconnected and cut off the power supply through the switch driving unit when the shielding unit is open-circuited, thereby solving the problem of danger caused by the failure to detect the leakage current in time due to the damage and open-circuit of the conductor shielding layer, and can better play a protective and safety role.

[0082] Figure 8 It is a structural block diagram of an electrical device according to an embodiment of the present invention.

[0083] like Figure 8 As shown, the electrical device 400 includes the leakage detection interruption circuit 100 of the above embodiment.

[0084] In this embodiment, the electrical device 400 may include an air conditioner, a rice cooker, a refrigerator, an induction cooker, a humidifier, etc.

[0085] The electrical equipment of the embodiment of the present invention, through the above-mentioned leakage detection interrupt circuit, can not only control the switch unit to be disconnected and cut off the access of the power supply through the switch driving unit when it is detected that there is leakage current in the live wire L or the neutral wire N to the shielding unit or the test switch is pressed, thereby realizing leakage protection and ensuring the safety of the plug being inserted into the power supply; but can also control the switch unit to be disconnected and cut off the power supply through the switch driving unit when the shielding unit is open-circuited, thereby solving the problem of danger caused by the failure to detect the leakage current in time due to the damage and open-circuit of the conductor shielding layer, and can better play a protective and safety role.

[0086] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0087] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0088] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0089] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0090] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0091] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A leakage detection interrupt circuit, characterized in that: The circuit is suitable for being connected between a power input terminal and a load, and comprises: A switch unit, used to control whether the power supply at the power input end is connected; A switch driving unit, used to control the on and off of the switch unit; A shielding unit, used for wrapping around a load power supply line to perform leakage detection on the load power supply line; The detection unit includes a power supply voltage stabilizing chip or a photoelectric coupler. The detection unit is connected to the shielding unit and the switch driving unit respectively, and is used to increase the voltage between the two detection pins of the power supply voltage stabilizing chip or the photoelectric coupling device to a voltage threshold when detecting that the shielding unit is open-circuited, so that the power supply voltage stabilizing chip or the photoelectric coupling device is turned on, thereby triggering the switch driving unit to control the switch unit to be disconnected, so as to cut off the access to the power supply.

2. The leakage detection interruption circuit according to claim 1, characterized in that: The detection unit includes a first detection end and a second detection end, and the shielding unit includes a conductor shielding layer, which is used to wrap the live wire connection line and the neutral wire connection line in the load power supply line, and is respectively connected to the first detection end and the second detection end, wherein when the connection between the first detection end and the second detection end is disconnected, the shielding unit is open-circuited.

3. The leakage detection interruption circuit according to claim 1, characterized in that: The detection unit is further configured to trigger the switch driving unit to control the switch unit to be disconnected when detecting leakage current flowing through the shielding unit, so as to cut off access to the power supply.

4. The leakage detection interruption circuit according to claim 2, characterized in that: The switch unit comprises: a trip coil switch, a first diode, a second diode and a first switch tube; The trip coil switch includes a first contact, a second contact and a winding, wherein the first contact is used to connect the neutral line of the power supply, the second contact is connected to the neutral line connection line in the load power supply line, the first end of the winding is connected to the live line connection line in the load power supply line, the second end of the winding is connected to the cathode of the second diode to form a first node, and the first node is connected to the third detection end of the detection unit, wherein the winding is used to trigger the on-off between the first contact and the second contact; The cathode of the first diode is connected to the neutral connection line; The anode of the second diode is connected to the anode of the first diode to form a second node, and the second node is connected to the first end of the switch driving unit; The first end of the first switch tube is connected to the second node, the second end of the first switch tube is connected to the first node, and the control end of the first switch tube is connected to the second end of the switch driving unit.

5. The leakage detection interruption circuit according to claim 4, characterized in that: The switch driving unit includes: a first capacitor, a third resistor, a fourth resistor and an eighth resistor; The first end of the first capacitor serves as the first end of the switch driving unit, and the second end of the first capacitor serves as the second end of the switch driving unit; The fourth resistor is connected in parallel with the first capacitor; The first end of the third resistor is connected to the second end of the first capacitor, and the second end of the third resistor is connected to the first detection end; A first end of the eighth resistor is connected to a first end of the first capacitor, and a second end of the eighth resistor is connected to a second end of the third resistor.

6. The leakage detection interruption circuit according to claim 5, characterized in that: When the detection unit includes the photoelectric coupler, it also includes a fifth resistor, a sixth resistor and a seventh resistor. The photocoupler has four pins, namely, a light-emitting diode cathode, a light-emitting diode anode, a phototransistor emitter, and a phototransistor collector. The phototransistor emitter is connected to the second end of the switch driving unit, and the phototransistor collector is connected to the first end of the fifth resistor. The light-emitting diode cathode serves as the first detection end, and the light-emitting diode anode serves as the second detection end, and the light-emitting diode cathode and the light-emitting diode anode are the two detection pins. The second end of the fifth resistor serves as the third detection end of the detection unit, the first end of the sixth resistor is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor is connected to the second detection end, the first end of the seventh resistor is connected to the second detection end, and the second end of the seventh resistor is connected to the first detection end.

7. The leakage detection interruption circuit according to claim 5, characterized in that: When the detection unit includes the power supply voltage stabilizing chip, it also includes a fifth resistor, a sixth resistor and a seventh resistor. The power supply voltage stabilizing chip has three pins, namely a cathode, an anode and a reference voltage terminal. The anode of the power supply voltage stabilizing chip serves as the first detection terminal, the reference voltage terminal of the power supply voltage stabilizing chip serves as the second detection terminal, and the anode and the reference voltage terminal of the power supply voltage stabilizing chip serve as the two detection pins. The first end of the fifth resistor is connected to the cathode of the power supply voltage stabilizing chip, the second end of the fifth resistor serves as the third detection terminal of the detection unit, the first end of the sixth resistor is connected to the live wire connection line in the load power supply line, the second end of the sixth resistor is connected to the second detection terminal, the first end of the seventh resistor is connected to the second detection terminal, and the second end of the seventh resistor is connected to the first detection terminal.

8. The leakage detection interruption circuit according to claim 6 or 7, characterized in that: The circuit further comprises: A testing unit, the testing unit comprising a testing switch, the testing switch being connected in parallel with the sixth resistor; The detection unit is further configured to trigger the switch driving unit to control the switch unit to be disconnected when detecting that the test switch is pressed, so as to cut off access to the power supply.

9. A leakage detection interrupter, characterized in that: It comprises the leakage detection interruption circuit according to any one of claims 1-8.

10. An electrical device, characterized in that: It comprises the leakage detection interruption circuit according to any one of claims 1-8.

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