Power line breakage protection device

Abstract

The invention provides a power line damage protection device, which comprises a power supply connecting plug, a power line and a power line damage protection unit, and is characterized in that the power supply connecting plug comprises a shell, a tripping mechanism, a live wire insertion piece, a zero line insertion piece, a grounding insertion piece and a circuit board; the power line damage protection unit comprises a tripping mechanism driving circuit and an electric leakage detection circuit. The power line comprises a live wire core wire, a zero wire core wire, a ground wire core wire, an insulating layer, an insulating sheath and an electric leakage detection layer, and the insulating layer of the live wire core wire and the insulating layer of the zero wire core wire are coated with the electric leakage detection layer; when the electric leakage detection layer breaks down, current triggers a silicon controlled rectifier Q1 in the tripping mechanism driving circuit to be conducted through the electric leakage detection layer and drives a tripping mechanism in the power supply connecting plug to cut off electric connection between a power supply and a load in time, so that electricity utilization safety is ensured, and the fire risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of leakage current detection circuit breakers (LCDIs), and in particular to a power line damage protection device. Background Art

[0002] As society develops and progresses, people's living standards continue to improve, and the use of various household electrical appliances is becoming more and more frequent. Due to space limitations, the power cords of most electrical appliances are hidden in hidden locations such as corners of the room, behind sofas, and under carpets. This makes the power cords easily affected by adverse factors such as animal biting, squeezing, and bending, which may cause short circuits in the wires and cause fires. In addition, the load current of household appliances such as air conditioners, vacuum cleaners, dehumidifiers, and microwave ovens is generally large, and the wires heat up more seriously, which accelerates the aging of the wires. Wire aging is also one of the main causes of electrical fires.

[0003] A leakage current detection circuit breaker, or LCDI for short, is an electrical fire safety protection device whose main function is to detect whether there is leakage current between the live wire, neutral wire, etc. of the power line between the power plug and the load electrical appliance (such as an air conditioner or dehumidifier) ​​and the protective layer (shield) of the power line. In the existing LCDI power line leakage current detection technology, the leakage detection layer outside the live wire core and the neutral wire core are not insulated from each other. When the leakage detection layer breaks in the middle section of the power line, if leakage occurs in the rear section of the power line at this time but cannot be detected by the LCDI, the LCDI is still in normal working condition, and there may be a fire risk in this case. Therefore, there is an urgent need in the art for an LCDI that can detect whether the protective layer and leakage detection layer of the power line are damaged. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a power line damage protection device, which is used to timely detect whether the leakage detection layer of the power line is broken, thereby reducing the risk of fire caused by misjudgment.

[0005] To achieve the above object, the present invention provides a power cord damage protection device, comprising a power connection plug, a power cord and a power cord damage protection unit, wherein:

[0006] The power connection plug comprises:

[0007] A housing, which is composed of an upper housing cover and a lower housing cover buckled together and fastened together by screws, and a power cord is connected to a power connection plug through a circular groove on the housing;

[0008] a circuit board, on which a power line damage protection unit is arranged and fixed to the lower cover of the housing;

[0009] A tripping mechanism comprises two conductive contacts, a balance frame, a solenoid, a reset button, a reset spring and a coil cover, wherein the two conductive contacts are supported by the balance frame, one end of each conductive contact can move up and down, and the end is provided with a silver contact capable of conducting electricity, and the other ends of the two conductive contacts are wiring terminals and connected to the power line; a metal locking piece is arranged in the balance frame, the metal locking piece is linked with the armature in the solenoid, and the balance frame is placed in the coil cover; the reset button comprises a pull rod, the pull rod pulls the metal locking piece in the balance frame to drive the balance frame to move up and down, and the reset spring is installed under the reset button;

[0010] A live wire plug, a neutral wire plug, and a grounding plug, wherein the live wire plug and the neutral wire plug are provided with conductive silver contacts, so that the silver contacts of the live wire plug and the silver contacts of the neutral wire plug can respectively contact the silver contacts of the movable ends of the two conductive contacts;

[0011] The power cord comprises: a live core wire, a neutral core wire, a ground core wire, an insulating layer, an insulating sheath, and a leakage detection layer; wherein the live core wire, the neutral core wire, and the ground core wire are all covered with an insulating layer, and the outermost layers are all covered with an insulating sheath, and the insulation layers of the live core wire and the neutral core wire are also covered with a leakage detection layer, and the leakage detection layer is composed of a copper shielding layer and an aluminum foil shielding layer;

[0012] In one embodiment of the present invention, the copper shielding layer is closely attached to the insulation layer of the neutral wire core and the insulation layer of the live wire core, and the copper shielding layer of the neutral wire core and the copper shielding layer of the live wire core are connected to the circuit board;

[0013] In one embodiment of the present invention, the aluminum foil shielding layer includes a conductive layer of aluminum foil and an insulating layer of aluminum foil, the conductive layer of aluminum foil is in close contact with the copper shielding layer, and the insulating layer of aluminum foil separates the copper shielding layer of the neutral wire core wire from the copper shielding layer of the live wire core wire to insulate each other.

[0014] The power line damage protection unit comprises: a tripping mechanism driving circuit and a leakage detection circuit, so that the leakage current triggers the tripping mechanism driving circuit to be turned on via the leakage detection circuit, so as to drive the tripping mechanism to disconnect the power connection between the power supply and the load, wherein:

[0015] In one embodiment of the present invention, the tripping mechanism driving circuit includes:

[0016] A thyristor Q1, wherein the anode of the thyristor Q1 is connected to the AC live wire through a solenoid, the cathode of the thyristor Q1 is connected to the anode of the diode D2, and the cathode of the diode D2 is connected to the AC neutral wire; the control electrode of the thyristor Q1 is connected to the anode of the Zener diode D3, and the cathode of the Zener diode D3 is connected to the resistor R2.

[0017] In one embodiment of the present invention, the control electrode of the thyristor Q1 can also be connected to one end of a bidirectional trigger diode Q2 and then connected to a resistor R2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of a diode D2.

[0018] In one embodiment of the present invention, the control electrode of the thyristor Q1 can be connected to a resistor R2 and then connected to one end of a bidirectional trigger diode Q2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of a diode D2.

[0019] In one embodiment of the present invention, the leakage detection circuit includes:

[0020] Resistors R4 and R6 are connected in series through conductive wires between the AC live wire and the leakage detection layer of the live wire core wire, and resistor R6 is connected to the leakage detection layer of the live wire core wire, and a connecting wire led out between resistor R4 and resistor R6 is connected to resistor R2; resistor R7 and a push switch Test are connected in series through conductive wires between the AC neutral wire and the leakage detection layer of the neutral wire core wire, and resistor R7 is connected to the leakage detection layer of the neutral wire core wire.

[0021] In one embodiment of the present invention, a resistor R5 and a key switch can be connected in series through a wire between the AC neutral line and the leakage detection layer of the neutral line core, and the resistor R5 is connected to the leakage detection layer of the neutral line core.

[0022] In one embodiment of the present invention, the live wire core leakage detection layer is electrically connected to the neutral wire core leakage detection layer.

[0023] In one embodiment of the present invention, an LED lamp and a current limiting resistor R1 are connected in series between the AC live wire and the AC neutral wire, and whether the plug is connected can be determined based on the on and off state of the LED.

[0024] In one embodiment of the present invention, a varistor MOV1 is provided between the AC live wire and the AC neutral wire to absorb peak voltage interference from the external power grid.

[0025] The present invention provides a power line damage protection device, which includes a power connection plug and a shielded cable, wherein a tripping mechanism and an electronic circuit are arranged in the plug. The conventional protection plug will not cut off the power supply when the leakage detection layer itself breaks in the middle section of the cable. The power line damage protection device proposed by the present invention designs a protection circuit to detect the integrity of the metal shielding layer of the cable, and will immediately cut off the power supply once the metal shielding layer of the cable breaks, thereby ensuring the safety of electricity use for loads and people and animals. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 The figure is a schematic diagram of a plug structure according to an embodiment of the present invention.

[0028] Figure 2 FIG. 4 is a schematic cross-sectional view of a power line according to an embodiment of the present invention.

[0029] Figure 3 A schematic diagram of a power line damage protection unit circuit according to an embodiment of the present invention Figure 1 .

[0030] Figure 4 A schematic diagram of a power line damage protection unit circuit according to a second embodiment of the present invention Figure 2 .

[0031] Figure 5 A schematic diagram of a power line damage protection unit circuit according to a third embodiment of the present invention Figure 3 .

[0032] Description of reference numerals: K1, K2-power switch; J1-solenoid; Q1-thyristor; C1, C2-capacitor; R1, R2, R3, R4, R5, R6, R7-resistor; D1, D2-diode; MOV1, MOV2-varistor; Test-button switch; LED-light-emitting diode; D3-voltage-stabilizing diode; 1-housing cover; 2-test key; 3-reset key; 4-reset spring; 5-reset key and test key silicon Rubber waterproof cap; 6-live wire plug; 7-neutral wire plug; 8-housing lower cover; 9-screw; 10-grounding plug; 11-circuit board; 12-test contact; 13-fixing plate; 14-balance frame; 15-conductive contact; 16-coil cover; 01-core wire; 202-insulating layer; 203-copper shielding layer; 204-aluminum shielding layer; 205-aluminum foil insulation layer; 206-sheath; 207-filler; L-live wire; N-neutral wire; G-grounding wire. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Figure 1 This is a schematic diagram of a plug structure according to an embodiment of the present invention. Figure 2 is a schematic cross-sectional view of a power line according to an embodiment of the present invention, Figure 3 A schematic diagram of a power line damage protection unit circuit according to an embodiment of the present invention Figure 1 .like Figure 1 , Figure 2 and Figure 3 As shown, this embodiment provides a power cord damage protection device, which includes a power connection plug, a power cord and a power cord damage protection unit;

[0035] The power connection plug, such as Figure 1 As shown, including:

[0036] A housing, which is composed of a housing upper cover 1 and a housing lower cover 8 buckled together and fastened together by screws 9, and a power cord is connected to a power connection plug through a circular groove on the housing;

[0037] A circuit board 11, on which a power line damage protection unit is provided and fixed to the lower cover 8 of the housing;

[0038] A tripping mechanism comprises two conductive contacts 15, a balance frame 14, a solenoid J1, a reset button 3, a reset spring 4 and a coil cover 16, and the tripping mechanism is fixed on the circuit board by the buckle of the coil cover;

[0039] The two conductive contacts 16 are supported by the balance frame 14, one end of each conductive contact can move up and down, and the end is provided with a silver contact capable of conducting electricity, and the other end of the two conductive contacts is a wiring terminal and is connected to the power line;

[0040] The balance frame 14 is provided with a metal lock plate, which is linked with the armature in the solenoid J1, and the balance frame is placed in the coil cover 16;

[0041] The reset button 3 includes a pull rod, and the pull rod pulls the metal lock piece in the balance frame to drive the balance frame to move up and down. The reset spring 4 is installed under the reset button 3;

[0042] A live wire plug 6, a neutral wire plug 7, and a grounding plug 10; the live wire plug 6 and the neutral wire plug 7 are provided with silver contacts capable of conducting electricity, so that the silver contacts of the live wire plug 6 and the silver contacts of the neutral wire plug 7 can respectively contact the silver contacts of the movable ends of the two conductive contacts 16; the live wire plug 6 and the neutral wire plug 7 can connect the external power supply of the plug and the conductive contacts inside the plug; the grounding plug 10 is connected to the ground wire of the power line;

[0043] A fixing plate 13 is welded on the upper cover 1, and the reset button 3 and the test button 2 are respectively inserted into the designated positions of the silicone waterproof cap.

[0044] When current flows through the solenoid J1, electromagnetic force is generated to drive the armature to move. The armature movement causes the metal lock piece in the balance frame to move together. The metal lock piece will slide out from the lower end of the reset button 3. At the same time, the reset button 3 moves upward under the reaction force of the reset spring 4. The balance frame 14 also moves downward due to the loss of the pulling force of the pull rod. At this time, the silver contacts of the live wire plug 6 and the neutral wire plug 7 are disconnected from the silver contacts at the movable ends of the two conductive contacts on the balance frame, thereby cutting off the electrical connection of the electrical equipment.

[0045] The power cord, such as Figure 2 As shown, it includes: a live core wire, a neutral core wire, a ground core wire, an insulating layer, an insulating sheath, and a leakage detection layer; wherein the live core wire, the neutral core wire, and the ground core wire are all covered with an insulating layer, and the outermost layers are all covered with an insulating sheath, and the insulation layers of the live core wire and the neutral core wire are also covered with a leakage detection layer, and the leakage detection layer is composed of a copper shielding layer and an aluminum foil shielding layer;

[0046] The copper shielding layer is in close contact with the insulation layer of the neutral wire and the live wire, and the copper shielding layer of the neutral wire and the live wire are connected to the circuit board. The material of the copper shielding layer is not limited to copper material, and can also be conductive materials such as iron and aluminum alloy;

[0047] The aluminum foil shielding layer includes an aluminum foil conductive layer and an aluminum foil insulating layer. The aluminum foil conductive layer is in close contact with the copper shielding layer. The aluminum foil insulating layer separates the copper shielding layer of the neutral wire core wire from the copper shielding layer of the live wire core wire to insulate each other.

[0048] Example 1

[0049] The power line damage protection unit is as follows: Figure 3 As shown, it includes: a trip mechanism driving circuit and a leakage detection circuit, so that the leakage current triggers the trip mechanism driving circuit to be turned on through the leakage detection circuit, so as to drive the trip mechanism to disconnect the power connection between the power supply and the load, wherein:

[0050] The trip mechanism driving circuit comprises:

[0051] A thyristor Q1, wherein the anode of the thyristor Q1 is connected to the AC live wire L through a solenoid J1, the cathode of the thyristor Q1 is connected to the anode of a diode D2, and the cathode of the diode D2 is connected to the AC neutral wire N; the control electrode of the thyristor Q1 is connected to the anode of a voltage-stabilizing diode D3, and the cathode of the voltage-stabilizing diode D3 is connected to a resistor R2, wherein the voltage-stabilizing diode D3 prevents the output voltage of the leakage detection circuit from being lower than the threshold voltage and triggering the tripping mechanism drive circuit to disconnect the power connection.

[0052] In this embodiment, a varistor MOV2 and a reverse-connected diode D1 are connected in parallel between the anode and cathode of the thyristor Q1, wherein the varistor MOV2 is used to absorb surge voltage across the thyristor Q1 to avoid malfunction.

[0053] The leakage detection circuit comprises:

[0054] A resistor R4 and a resistor R6 connected in series by a wire are connected between the AC live wire L and the leakage detection layer of the live wire core wire (i.e., the AC live wire shielding layer), and the resistor R6 is connected to the leakage detection layer of the live wire core wire, and a connecting wire drawn between the resistor R4 and the resistor R6 is connected to the resistor R2;

[0055] In this embodiment, the leakage detection layer of the live wire core wire close to the power input end (input end) is called the AC live wire shielding layer power end, and the leakage detection layer of the live wire core wire close to the power output end (output end) is called the AC live wire shielding layer load end;

[0056] A wire series resistor R7 and a key switch Test are connected between the AC neutral wire N and the leakage detection layer of the neutral wire core wire (i.e., the AC neutral wire N wire shielding layer), and the resistor R7 is connected to the leakage detection layer of the neutral wire core wire;

[0057] The leakage detection layer of the live wire core wire is electrically connected to the leakage detection layer of the neutral wire core wire;

[0058] In this embodiment, the leakage detection layer of the neutral wire core wire close to the power input end (input end) is called the AC neutral wire shielding layer power end, and the leakage detection layer of the neutral wire core wire close to the power output end (output end) is called the AC neutral wire shielding layer load end.

[0059] In this embodiment, a capacitor C2 and a resistor R3 are connected in parallel between the control electrode of the thyristor Q1 and the anode of the diode D2 to form an RC filter circuit;

[0060] In this embodiment, a capacitor C1 is connected in parallel between the cathode of the voltage stabilizing diode D3 and the anode of the diode D2 for filtering;

[0061] In this embodiment, an LED lamp and a current-limiting resistor R1 are connected in series between the AC live wire L and the AC neutral wire N, and whether the plug is connected can be determined according to the on and off state of the LED.

[0062] In this embodiment, a varistor MOV1 is provided between the AC live wire L and the AC neutral wire N to absorb peak voltage interference from an external power grid.

[0063] The working principle of the power cord damage protection device is as follows: Figure 3 As shown, the description is as follows:

[0064] Under normal circumstances: the current passes through the AC live wire L, through the resistor R4, the resistor R6, through the AC live wire shielding layer power supply end, the AC live wire shielding layer load end to the AC neutral wire shielding layer load end, the AC neutral wire shielding layer power supply end, and then through the resistor R5, the diode D2, and then flows into the AC neutral wire N. At this time, the tripping mechanism is in a closed state, and the load equipment can be powered on and used normally.

[0065] When the live wire core or neutral wire core in the power line touches the AC live wire shield or the AC neutral wire shield, and the metal shield in the power line breaks and opens: at this time, the voltage N is negative and L is positive, and the current flows through the AC live wire L, the AC live wire shield, and the AC neutral wire shield to the resistor R5 and the resistor R3, and the thyristor Q1 control electrode. At this time, the voltage of the Q1 control electrode increases and Q1 is turned on. The current flows to the AC neutral wire N through the solenoid J1, the thyristor Q1, and the diode D2. The current drives the iron core and drives the tripping mechanism to disconnect, cutting off the power connection between the AC power supply end and the load end.

[0066] When the AC live wire shield or AC neutral wire shield is damaged and disconnected: the current flows through the AC live wire L, resistor R4, resistor R2, to the voltage stabilizing diode D3 and triggers the thyristor Q1 to turn on. The current flows through the solenoid J1, thyristor Q1, and diode D2 to the AC neutral wire N. The solenoid current generates electromagnetic force to drive the armature to move, drive the trip mechanism contacts to disconnect, and cut off the power supply in time to reduce the risk of fire.

[0067] Example 2

[0068] Figure 4 A schematic diagram of a power line damage protection unit circuit according to an embodiment of the present invention Figure 2 ,like Figure 4 As shown, the difference compared with embodiment 1 is mainly in the power damage protection unit; embodiment 2 provides a power line damage protection device, and its power connection plug and power line are the same as those of embodiment 1, which will not be repeated here;

[0069] The power line damage protection unit is as follows: Figure 4 As shown, it includes: a trip mechanism driving circuit and a leakage detection circuit, so that the leakage current triggers the trip mechanism driving circuit to turn on through the leakage detection circuit, so as to drive the trip mechanism to disconnect the power connection between the power supply and the load, wherein:

[0070] The trip mechanism driving circuit comprises:

[0071] A thyristor Q1, wherein the anode of the thyristor Q1 is connected to the AC live wire L through a solenoid J1, the cathode of the thyristor Q1 is connected to the anode of a diode D2, and the cathode of the diode D2 is connected to the AC neutral wire N; the control electrode of the thyristor Q1 is connected to one end of a bidirectional trigger diode Q2 and then connected to a resistor R2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2, wherein the bidirectional trigger diode Q2 prevents the output voltage of the leakage detection circuit from being lower than the threshold voltage and triggers the trip mechanism drive circuit to disconnect the power connection.

[0072] In this embodiment, a reverse-connected diode D1 is connected in parallel between the anode and cathode of the thyristor Q1 to absorb surge voltage across the two ends of the thyristor Q1 to avoid malfunction.

[0073] In this embodiment, a capacitor C1 and a resistor R3 are connected in parallel between the control electrode and the cathode of the thyristor Q1 to form an RC filter circuit.

[0074] The leakage detection circuit comprises:

[0075] A resistor R4 and a resistor R6 connected in series by a wire are connected between the AC live wire L and the leakage detection layer of the live wire core wire (i.e., the AC live wire shielding layer), and the resistor R6 is connected to the leakage detection layer of the live wire core wire, and a connecting wire drawn between the resistor R4 and the resistor R6 is connected to the resistor R2;

[0076] A wire series resistor R5 and a key switch Test are connected between the AC neutral wire N and the leakage detection layer of the neutral wire core wire (i.e., the AC neutral wire N wire shielding layer), and the resistor R5 is connected to the leakage detection layer of the neutral wire core wire;

[0077] The leakage detection layer of the live wire core wire is electrically connected to the leakage detection layer of the neutral wire core wire;

[0078] The working principle of the power cord damage protection device is as follows: Figure 4 As shown, the description is as follows:

[0079] The working principle of the power line damage protection device in Example 2 under normal conditions, when the AC live line shielding layer or the AC neutral line shielding layer is damaged and disconnected, is the same as that in Example 1 and will not be repeated here;

[0080] When the live wire core or neutral wire core in the power line touches the AC live wire shield or the AC neutral wire shield, and the metal shield in the power line breaks and opens: at this time, the voltage N is negative and L is positive, and the current flows through the AC live wire L, the AC live wire shield, and the AC neutral wire shield to the resistor R5, the bidirectional trigger diode Q2, and the control electrode of the thyristor Q1. At this time, the voltage of the Q1 control electrode increases and Q1 is turned on. The current flows to the AC neutral wire N through the solenoid J1, the thyristor Q1, and the diode D2. The current drives the iron core and drives the tripping mechanism to disconnect, cutting off the power connection between the AC power supply end and the load end.

[0081] Example 3

[0082] Figure 5 A schematic diagram of a power line damage protection unit circuit according to an embodiment of the present invention Figure 3 ,like Figure 5As shown, the main difference compared with embodiment 1 is the power damage protection unit; embodiment 3 provides a power line damage protection device, and its power connection plug and power line are the same as those of embodiment 1, which will not be repeated here;

[0083] The power line damage protection unit is as follows: Figure 5 As shown, it includes: a trip mechanism driving circuit and a leakage detection circuit;

[0084] The trip mechanism driving circuit comprises:

[0085] A thyristor Q1, wherein the anode of the thyristor Q1 is connected to the AC live wire L through a solenoid J1, the cathode of the thyristor Q1 is connected to the anode of a diode D2, and the cathode of the diode D2 is connected to the AC neutral wire N; the control electrode of the thyristor Q1 is connected to a resistor R2 and then connected to one end of a bidirectional trigger diode Q2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2, wherein the bidirectional trigger diode Q2 prevents the output voltage of the leakage detection circuit from being lower than the threshold voltage and triggers the trip mechanism drive circuit to disconnect the power connection.

[0086] The leakage detection circuit comprises:

[0087] A resistor R4 and a resistor R6 connected in series by a wire are connected between the AC live wire L and the leakage detection layer of the live wire core wire (i.e., the AC live wire shielding layer), and the resistor R6 is connected to the leakage detection layer of the live wire core wire, and a connecting line drawn between the resistor R4 and the resistor R6 is connected to a connecting line drawn between the resistor R2 and the bidirectional starting diode;

[0088] A wire series resistor R5 and a key switch Test are connected between the AC neutral wire N and the leakage detection layer of the neutral wire core wire (i.e., the AC neutral wire N wire shielding layer), and the resistor R5 is connected to the leakage detection layer of the neutral wire core wire;

[0089] The leakage detection layer of the live wire core wire is electrically connected to the leakage detection layer of the neutral wire core wire;

[0090] The working principle of the power cord damage protection device is as follows: Figure 5 As shown, the description is as follows:

[0091] The working principle of the power line damage protection device in Example 3 under normal conditions, when the AC live line shielding layer or the AC neutral line shielding layer is damaged and disconnected, is the same as that in Example 1 and will not be repeated here;

[0092] When the live wire core or neutral wire core in the power line touches the AC live wire shield or the AC neutral wire shield, and the metal shield in the power line breaks and opens: at this time, the voltage N is negative and L is positive, and the current passes through the AC live wire L, the AC live wire shield, and the AC neutral wire shield to the resistor R5, the bidirectional trigger diode Q2, and then to the control electrode of the thyristor Q1 after the resistor R2. At this time, the voltage of the Q1 control electrode increases and Q1 is turned on. The current flows to the AC neutral wire N through the solenoid J1, the thyristor Q1, and the diode D2. The current drives the iron core and drives the tripping mechanism to disconnect, cutting off the power connection between the AC power supply end and the load end.

[0093] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0094] Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description of the embodiment, or can be changed accordingly and located in one or more devices different from the embodiment. The modules in the above embodiment can be combined into one module, or can be further divided into multiple sub-modules.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power line damage protection device, characterized in that: It includes a power connection plug, a power cord and a power cord damage protection unit, wherein: The power connection plug comprises: A housing, comprising an upper housing cover and a lower housing cover buckled together and fastened together by screws, wherein the power cord is connected to the power connection plug through a circular groove on the housing; a circuit board, on which the power line damage protection unit is arranged and fixed to the lower cover of the housing; A tripping mechanism comprises two conductive contacts, a balance frame, a solenoid, a reset button, a reset spring and a coil cover, wherein the two conductive contacts are supported by the balance frame, one end of each conductive contact can move up and down, and the end is provided with a silver contact capable of conducting electricity, and the other ends of the two conductive contacts are wiring terminals and connected to the power line; a metal locking piece is arranged in the balance frame, the metal locking piece is linked with the armature in the solenoid, and the balance frame is placed in the coil cover; the reset button comprises a pull rod, the pull rod pulls the metal locking piece in the balance frame to drive the balance frame to move up and down, and the reset spring is installed under the reset button; A live wire plug, a neutral wire plug and a grounding plug, wherein the live wire plug and the neutral wire plug are provided with conductive silver contacts, so that the silver contacts of the live wire plug and the silver contacts of the neutral wire plug can respectively contact the silver contacts of the movable ends of the two conductive contacts; The power cord comprises: a live core wire, a neutral core wire, a ground core wire, an insulating layer, an insulating sheath and a leakage detection layer; wherein the live core wire, the neutral core wire and the ground core wire are all covered with an insulating layer, and the outermost layers are all covered with an insulating sheath, and the insulation layers of the live core wire and the neutral core wire are also covered with a leakage detection layer, and the leakage detection layer is composed of a copper shielding layer and an aluminum foil shielding layer; The power line damage protection unit includes: a trip mechanism driving circuit and a leakage detection circuit, so that the leakage current triggers the trip mechanism driving circuit to conduct through the leakage detection circuit, so as to drive the trip mechanism to disconnect the power connection between the power supply and the load.

2. The power line damage protection device according to claim 1, characterized in that: The copper shielding layer is closely attached to the insulation layer of the neutral wire core and the insulation layer of the live wire core, and the copper shielding layer of the neutral wire core and the copper shielding layer of the live wire core are connected to the circuit board.

3. The power line damage protection device according to claim 1, characterized in that: The aluminum foil shielding layer includes an aluminum foil conductive layer and an aluminum foil insulating layer. The aluminum foil conductive layer is in close contact with the copper shielding layer. The aluminum foil insulating layer separates the copper shielding layer of the neutral wire core wire from the copper shielding layer of the live wire core wire to insulate each other.

4. The power line damage protection device according to claim 1, characterized in that: The trip mechanism driving circuit comprises: A thyristor Q1, wherein the anode of the thyristor Q1 is connected to the AC live wire through the solenoid, the cathode of the thyristor Q1 is connected to the anode of the diode D2, and the cathode of the diode D2 is connected to the AC neutral wire; the control electrode of the thyristor Q1 is connected to the anode of the Zener diode D3, and the cathode of the Zener diode D3 is connected to the resistor R2.

5. The power line damage protection device according to claim 4, characterized in that: The control electrode of the thyristor Q1 can also be connected to one end of the bidirectional trigger diode Q2 and then connected to the resistor R2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2.

6. The power line damage protection device according to claim 4, characterized in that: The control electrode of the thyristor Q1 can also be connected to a resistor R2 and then connected to one end of a bidirectional trigger diode Q2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of a diode D2.

7. The power line damage protection device according to claim 1, characterized in that: The leakage detection circuit includes: a resistor R4 and a resistor R6 connected in series through a wire between the AC live wire and the leakage detection layer of the live wire core wire, and the resistor R6 is connected to the leakage detection layer of the live wire core wire; a resistor R7 and a push-button switch are connected in series through a wire between the AC neutral wire and the leakage detection layer of the neutral wire core wire, and the resistor R7 is connected to the leakage detection layer of the neutral wire core wire.

8. The power line damage protection device according to claim 7, characterized in that: A resistor R5 and a key switch can also be connected in series through a conductive wire between the AC neutral wire and the leakage detection layer of the neutral wire core, and the resistor R5 is connected to the leakage detection layer of the neutral wire core.

9. The power line damage protection device according to claim 7, characterized in that: The live wire core leakage detection layer is electrically connected to the neutral wire core leakage detection layer.

10. The power line damage protection device according to claim 4, characterized in that: A varistor MOV1 is also provided between the AC live wire and the AC neutral wire, and an LED lamp and a current limiting resistor R1 are also connected in series between the AC live wire and the AC neutral wire.

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