Power cord damage protection apparatus

Abstract

Provided is a power cord damage protection apparatus, comprising a power connection plug, a power cord and a power cord damage protection unit, wherein the power connection plug comprises a housing, a tripping mechanism, a live wire blade (6), a neutral wire blade (7), a ground wire blade (10) and a circuit board (11); the power cord damage protection unit comprises: a tripping mechanism drive circuit and a leakage detection circuit; and the power cord comprises a live core wire, a neutral core wire, a ground core wire, insulating layers (202), an insulating sheath (206), and a leakage detection layer. The insulating layers (202) of the live core wire and the neutral core wire are both coated with the leakage detection layer; and when a fault occurs in the leakage detection layer, current passes through the leakage detection layer to trigger the conduction of a silicon-controlled rectifier Q1 in the tripping mechanism drive circuit, and drive the tripping mechanism in the power connection plug to promptly cut off the power connection between a power supply and a load, thereby ensuring electrical safety and reducing the risk of fire.

Description

A power cord damage protection device Technical Field

[0001] This invention relates to the field of leakage current detection circuit breakers (LCDI), and more specifically, to a power line damage protection device. Background Technology

[0002] With social development and progress, people's living standards are constantly improving, and the use of various household appliances is becoming increasingly frequent. Due to space constraints, the power cords of most appliances are hidden in concealed locations such as room corners, behind sofas, and under carpets. This makes the power cords susceptible to damage from animals biting, squeezing, bending, and other adverse factors, which can potentially cause short circuits and even fires. Furthermore, household appliances such as air conditioners, vacuum cleaners, dehumidifiers, and microwave ovens generally have high current loads, causing their wires to heat up significantly. This accelerates the aging of the wires, which is also a major cause of electrical fires.

[0003] A leakage current detection circuit breaker (LCDI) is an electrical fire safety protection device. Its main function is to detect whether there is leakage current between the live wire, neutral wire, and the protective layer (shield) of the power cord between the power plug and the load appliance (such as an air conditioner or dehumidifier). Existing LCDI power cord leakage current detection technology does not insulate the leakage detection layer outside the live wire and neutral wire. If the leakage detection layer breaks in the middle of the power cord, and leakage occurs in the later part of the power cord but cannot be detected by the LCDI, the LCDI will still operate normally, potentially posing a fire risk. Therefore, there is an urgent need in this field for an LCDI that can detect whether the power cord protective layer and leakage detection layer are damaged. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a power cord damage protection device that can promptly detect whether the leakage detection layer of the power cord has broken, thereby reducing the risk of fire caused by misjudgment.

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

[0006] The power connector includes:

[0007] The outer casing consists of an upper cover and a lower cover that are fastened together with screws. The power cord is connected to the power connector plug through a circular groove on the outer casing.

[0008] A circuit board with a power cord damage protection unit fixed to the bottom cover of the housing;

[0009] A tripping mechanism includes two conductive contacts, a balance frame, a solenoid, a reset button, a reset spring, and a coil cover. The two conductive contacts are supported by the balance frame. One end of each conductive contact is movable up and down and has a conductive silver contact. The other end of the two conductive contacts is a wiring terminal connected to the power cord. A metal locking plate is provided inside the balance frame, and the metal locking plate is linked to the armature inside the solenoid. The balance frame rests inside the coil cover. The reset button includes a pull rod that pulls the metal locking plate inside the balance frame to move the balance frame up and down. The reset spring is installed below the reset button.

[0010] A live wire connector, a neutral wire connector, and a ground connector are provided. The live wire connector and the neutral wire connector are provided with conductive silver contacts so that the silver contacts of the live wire connector and the neutral wire connector can respectively contact the silver contacts of the movable ends of the two conductive contacts.

[0011] The power cord includes: a live wire, a neutral wire, a ground wire, an insulation layer, an insulation sheath, and a leakage current detection layer; wherein, the live wire, the neutral wire, and the ground wire are all covered with an insulation layer, and the outermost layer of each is covered with an insulation sheath; the insulation layers of the live wire and the neutral wire are also covered with a leakage current detection layer, which 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 in close contact with 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 and the copper shielding layer of the live wire core to insulate them from each other.

[0014] The power cord damage protection unit includes a tripping mechanism drive circuit and a leakage current detection circuit, so that leakage current triggers the tripping mechanism drive circuit to conduct via the leakage current detection circuit, thereby driving 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 drive circuit includes:

[0016] A thyristor Q1 is provided. The anode of the thyristor Q1 is connected to the AC live wire via 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 a resistor R2 after being connected to one end of the bidirectional trigger diode Q2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2.

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

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

[0020] A resistor R4 and a resistor R6 are connected in series with a wire between the AC live wire and the leakage detection layer of the live wire core. Resistor R6 is connected to the leakage detection layer of the live wire core. A connecting wire leading out between resistor R4 and resistor R6 is connected to resistor R2. A resistor R7 and a push-button switch Test are connected in series with a wire between the AC neutral wire and the leakage detection layer of the neutral wire core. Resistor R7 is connected to the leakage detection layer of the neutral wire core.

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

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

[0023] In one embodiment of the invention, an LED and a current-limiting resistor R1 are connected in series between the AC live wire and the AC neutral wire, so that the plug is connected based on the on / 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 voltage spikes from the external power grid.

[0025] This invention provides a power cord damage protection device, which includes a power connector and a shielded cable. The connector contains a tripping mechanism and electronic circuitry. Traditional protective plugs do not cut off power when the leakage detection layer breaks in the middle of the cable. The power cord damage protection device proposed in this invention employs a protection circuit to detect the integrity of the cable's metal shielding layer. Once the cable's metal shielding layer breaks, it immediately cuts off the power, ensuring the safety of the load and the electrical systems used by people and animals. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

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

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

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

[0030] Figure 4 is a schematic diagram of the power line damage protection unit circuit of Embodiment 2 of the present invention.

[0031] Figure 5 is a schematic diagram of the power line damage protection unit circuit of an embodiment 3 of the present invention.

[0032] Explanation of reference numerals in the attached diagram: K1, K2 - Power switches; J1 - Solenoid; Q1 - SCR; C1, C2 - Capacitors; R1, R2, R3, R4, R5, R6, R7 - Resistors; D1, D2 - Diodes; MOV1, MOV2 - Varistors; Test - Push-button switch; LED - Light-emitting diode; D3 - Zener diode; 1 - Top cover; 2 - Test button; 3 - Reset button; 4 - Reset spring; 5 - Silicon for both reset and test buttons. 6-Waterproof cap; 7-Live wire connector; 8-Neutral wire connector; 9-Lower cover of outer casing; 10-Screw; 11-Grounding connector; 12-Circuit board; 13-Test contact; 14-Fixing plate; 15-Balance frame; 16-Conductive contact; 17-Coil cover; 01-Core wire; 202-Insulation layer; 203-Copper shielding layer; 204-Aluminum shielding layer; 205-Aluminum foil insulation layer; 206-Sheath; 207-Filling material; L-Live wire; N-Neutral wire; G-Grounding wire. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

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

[0035] The power connector, as shown in Figure 1, includes:

[0036] A housing consists of an upper cover 1 and a lower cover 8 that are fastened together by screws 9. The power cord is connected to the power connector plug through a circular groove on the housing.

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

[0038] A tripping mechanism includes two conductive contacts 15, a balance frame 14, a solenoid J1, a reset button 3, a reset spring 4, and a coil cover 16. The tripping mechanism is fixed to the circuit board by the snap-fit ​​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 that can conduct electricity. The other end of the two conductive contacts is a terminal and is connected to the power line.

[0040] The balance frame 14 is provided with a metal locking plate, which is linked to the armature in the solenoid J1. The balance frame is placed inside the coil cover 16.

[0041] The reset button 3 includes a pull rod, which pulls the metal locking piece inside the balance frame to drive the balance frame to move up and down. The reset spring 4 is installed below the reset button 3.

[0042] The plug includes a live wire connector 6, a neutral wire connector 7, and a ground connector 10. The live wire connector 6 and the neutral wire connector 7 are provided with conductive silver contacts, allowing the silver contacts of the live wire connector 6 and the neutral wire connector 7 to respectively contact the silver contacts at the movable ends of the two conductive contacts 16. The live wire connector 6 and the neutral wire connector 7 can connect to the external power supply and the internal conductive contacts of the plug. The ground connector 10 is connected to the ground wire of the power supply line.

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

[0044] When current flows through solenoid J1, it generates an electromagnetic force that drives the armature to move. This movement of the armature causes the metal locking plate inside the balance frame to move as well. The metal locking plate slides out from the lower end of the reset button 3, and simultaneously, 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 from the lever. At this point, the silver contacts of the live wire plug 6 and the neutral wire plug 7 disconnect 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, as shown in Figure 2, includes: a live wire, a neutral wire, a ground wire, an insulation layer, an insulation sheath, and a leakage detection layer; wherein, the live wire, the neutral wire, and the ground wire are all covered with an insulation layer, and the outermost layer of each is covered with an insulation sheath; the insulation layers of the live wire and the neutral wire are also covered with a leakage detection layer, which 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 core and the live wire core. 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. The material of the copper shielding layer is not limited to copper, but can also be conductive materials such as iron and aluminum alloy.

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

[0048] Example 1

[0049] The power cord damage protection unit, as shown in Figure 3, includes: a tripping mechanism drive circuit and a leakage current detection circuit, so that leakage current triggers the tripping mechanism drive circuit to conduct via the leakage current detection circuit, thereby driving the tripping mechanism to disconnect the power connection between the power supply and the load, wherein:

[0050] The tripping mechanism drive circuit includes:

[0051] A thyristor Q1 is provided, with its anode connected to the AC live wire L via a solenoid J1, and its cathode connected to the anode of diode D2, the cathode of which is connected to the AC neutral wire N. The control electrode of the thyristor Q1 is connected to the anode of a Zener diode D3, and the cathode of the Zener diode D3 is connected to a resistor R2. The Zener diode D3 is used to prevent the leakage current detection circuit from triggering the tripping mechanism drive circuit to disconnect the power connection when the output voltage is lower than the threshold voltage.

[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. The varistor MOV2 is used to absorb the surge voltage across the thyristor Q1 to prevent malfunction.

[0053] The leakage current detection circuit includes:

[0054] The AC live wire L and the leakage detection layer (i.e., AC live wire shielding layer) are connected in series by a wire with resistors R4 and R6, and resistor R6 is connected to the leakage detection layer of the live wire core. The connecting line led out between resistors R4 and R6 is connected to resistor R2.

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

[0056] The AC neutral wire N and the leakage detection layer (i.e., the AC neutral wire N shielding layer) are connected in series by a wire and a resistor R7 and a push-button switch Test, and the resistor R7 is connected to the leakage detection layer of the neutral wire core.

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

[0058] In this embodiment, the leakage detection layer of the neutral wire near the power input end is called the AC neutral wire shielding layer power supply end, and the leakage detection layer of the neutral wire near the power 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 Zener diode D3 and the anode of the diode D2 for filtering.

[0061] In this embodiment, an LED and a current-limiting resistor R1 are connected in series between the AC live wire L and the AC neutral wire N, so that the plug can be determined as to whether it is connected based on the on / 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 voltage spikes from the external power grid.

[0063] The working principle of the power cord damage protection device is shown in Figure 3, and explained below:

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

[0065] When the live wire or neutral wire core, AC live wire shield, or AC neutral wire shield touches each other, or when the metal shielding layer inside the power cord breaks and opens a circuit: At this time, voltage N is negative and L is positive. Current flows through AC live wire L, AC live wire shield, AC neutral wire shield to resistors R5 and R3, and the control electrode of SCR Q1. The voltage at the control electrode of Q1 increases, and Q1 conducts. Current then flows through solenoid J1, SCR Q1, and diode D2 to AC neutral wire N. This current drives the iron core and triggers the tripping mechanism to disconnect, cutting off the power connection between the AC power supply terminal and the load terminal.

[0066] When the shielding layer of the AC live wire or the AC neutral wire is damaged and disconnected: the current flows through the AC live wire L, resistor R4, resistor R2, and then to the Zener diode D3, triggering the SCR Q1 to conduct. The current then flows through the solenoid J1, SCR Q1, and diode D2 to the AC neutral wire N. The solenoid current generates electromagnetic force that drives the armature to move, causing the trip mechanism contacts to open and promptly cut off the power supply, reducing the risk of fire.

[0067] Example 2

[0068] Figure 4 is a second schematic diagram of the power cord damage protection unit circuit according to an embodiment of the present invention. As shown in Figure 4, the main difference between the embodiment and the first embodiment is the power cord damage protection unit. The second embodiment provides a power cord damage protection device, whose power connector plug and power cord are the same as those in the first embodiment, and will not be described again here.

[0069] The power cord damage protection unit, as shown in Figure 4, includes: a tripping mechanism drive circuit and a leakage current detection circuit, so that leakage current triggers the tripping mechanism drive circuit to conduct via the leakage current detection circuit, thereby driving the tripping mechanism to disconnect the power connection between the power supply and the load, wherein:

[0070] The tripping mechanism drive circuit includes:

[0071] A thyristor Q1 is provided. The anode of the thyristor Q1 is connected to the AC live wire L via 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. The other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2. The bidirectional trigger diode Q2 is used to prevent the leakage current detection circuit from triggering the tripping mechanism drive circuit to disconnect the power connection when the output voltage is lower than the threshold voltage.

[0072] In this embodiment, a reverse-connected diode D1 is connected in parallel between the anode and cathode of the thyristor Q1 to absorb the surge voltage across the thyristor Q1 and prevent 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 current detection circuit includes:

[0075] The AC live wire L and the leakage detection layer (i.e., AC live wire shielding layer) are connected in series by a wire with resistors R4 and R6, and resistor R6 is connected to the leakage detection layer of the live wire core. The connecting line led out between resistors R4 and R6 is connected to resistor R2.

[0076] The AC neutral wire N and the leakage detection layer (i.e., the AC neutral wire N shielding layer) are connected in series by a wire, a resistor R5 and a push-button switch Test, and the resistor R5 is connected to the leakage detection layer of the neutral wire core.

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

[0078] The working principle of the power cord damage protection device is shown in Figure 4, and explained below:

[0079] The working principle of the power cord damage protection device in Example 2 is the same as that in Example 1 under normal conditions and when the shielding layer of the AC live wire or the shielding layer of the AC neutral wire is damaged and disconnected;

[0080] When the live wire or neutral wire core, or the AC live wire shield or AC neutral wire shield, comes into contact, or when the metal shield within the power cord breaks and opens a circuit: At this time, voltage N is negative and L is positive. Current flows through the AC live wire L, the AC live wire shield, the AC neutral wire shield, to resistor R5, bidirectional trigger diode Q2, and the control electrode of thyristor Q1. The voltage at the control electrode of Q1 increases, and Q1 conducts. Current then flows through solenoid J1, thyristor Q1, and diode D2 to the AC neutral wire N. This current drives the iron core and triggers the tripping mechanism to disconnect, cutting off the power connection between the AC power supply terminal and the load terminal.

[0081] Example 3

[0082] Figure 5 is a schematic diagram of the power cord damage protection unit circuit of an embodiment of the present invention. As shown in Figure 5, the main difference between the embodiment and the first embodiment is the power cord damage protection unit. The third embodiment provides a power cord damage protection device, whose power connector plug and power cord are the same as those in the first embodiment, and will not be described again here.

[0083] The power cord damage protection unit, as shown in Figure 5, includes: a tripping mechanism drive circuit and a leakage current detection circuit;

[0084] The tripping mechanism drive circuit includes:

[0085] A thyristor Q1 is provided. The anode of the thyristor Q1 is connected to the AC live wire L via 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 to one end of a bidirectional trigger diode Q2. The other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2. The bidirectional trigger diode Q2 is used to prevent the leakage current detection circuit from triggering the tripping mechanism drive circuit to disconnect the power connection when the output voltage is lower than the threshold voltage.

[0086] The leakage current detection circuit includes:

[0087] The AC live wire L and the leakage detection layer (i.e., AC live wire shielding layer) of the live wire core wire are connected in series by a wire with resistors R4 and R6, and resistor R6 is connected to the leakage detection layer of the live wire core wire. The connecting line led out between resistors R4 and R6 is connected to the connecting line led out between resistor R2 and bidirectional trigger diode.

[0088] The AC neutral wire N and the leakage detection layer (i.e., the AC neutral wire N shielding layer) are connected in series by a wire, a resistor R5 and a push-button switch Test, and the resistor R5 is connected to the leakage detection layer of the neutral wire core.

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

[0090] The working principle of the power cord damage protection device is shown in Figure 5, and explained below:

[0091] The working principle of the power cord damage protection device in Example 3 is the same as that in Example 1 under normal conditions and when the shielding layer of the AC live wire or the shielding layer of the AC neutral wire is damaged and disconnected;

[0092] When the live wire or neutral wire core, AC live wire shield, or AC neutral wire shield touches each other, or when the metal shielding layer inside the power cord breaks and opens a circuit: At this time, voltage N is negative and L is positive. Current flows through AC live wire L, AC live wire shield, AC neutral wire shield to resistor R5, bidirectional trigger diode Q2, and then through resistor R2 to the control electrode of thyristor Q1. At this time, the voltage at the control electrode of Q1 increases, and Q1 conducts. Current then flows through solenoid J1, thyristor Q1, and diode D2 to AC neutral wire N. The current drives the iron core and triggers the tripping mechanism to disconnect, cutting off the power connection between the AC power supply terminal and the load terminal.

[0093] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0094] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they 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, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power cord damage protection device, characterized in that, Includes a power connector, a power cord, and a power cord damage protection unit, wherein: The power connector includes: A housing consisting of an upper housing cover and a lower housing cover fastened together by screws, wherein the power cord is connected to the power connector plug through a circular groove on the housing. A circuit board having the power cord damage protection unit installed thereon and fixed to the lower cover of the housing; A tripping mechanism includes two conductive contacts, a balance frame, a solenoid, a reset button, a reset spring, and a coil cover. The two conductive contacts are supported by the balance frame. One end of each conductive contact is movable up and down and has a conductive silver contact. The other end of the two conductive contacts is a wiring terminal connected to the power cord. A metal locking plate is installed inside the balance frame, and the metal locking plate is linked to the armature inside the solenoid. The balance frame is placed inside the coil cover. The reset button includes a pull rod that pulls the metal locking plate inside the balance frame to move the balance frame up and down. The reset spring is installed below the reset button. A live wire connector, a neutral wire connector, and a ground connector are provided. The live wire connector and the neutral wire connector are provided with conductive silver contacts so that the silver contacts of the live wire connector and the silver contacts of the neutral wire connector can respectively contact the silver contacts of the movable ends of the two conductive contacts. The power cord includes: a live wire, a neutral wire, a ground wire, an insulation layer, an insulation sheath, and a leakage detection layer; wherein, the live wire, the neutral wire, and the ground wire are all covered with an insulation layer, and the outermost layer of each is covered with an insulation sheath; the insulation layers of the live wire and the neutral wire are also covered with a leakage detection layer, which is composed of a copper shielding layer and an aluminum foil shielding layer; The power cord damage protection unit includes a tripping mechanism drive circuit and a leakage current detection circuit, so that leakage current triggers the tripping mechanism drive circuit to conduct through the leakage current detection circuit, thereby driving the tripping mechanism to disconnect the power connection between the power supply and the load.

2. The power cord damage protection device according to claim 1, characterized in that, The copper shielding layer is in close contact with the insulation layer of the neutral wire core and the insulation layer of the live wire core, and the copper shielding layers of the neutral wire core and the live wire core are connected to the circuit board.

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

4. The power cord damage protection device according to claim 1, characterized in that, The tripping mechanism drive circuit includes: A thyristor Q1 is provided, 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 cord 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 a resistor R2. The other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2.

6. The power cord 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 the bidirectional trigger diode Q2, and the other end of the bidirectional trigger diode Q2 is connected to the anode of the diode D2.

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

8. The power cord damage protection device according to claim 7, characterized in that, The AC neutral wire and the leakage detection layer of the neutral wire core can also be connected in series with a resistor R5 and a push-button switch via a wire, and the resistor R5 is connected to the leakage detection layer of the neutral wire core.

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

10. The power cord 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 light and a current-limiting resistor R1 are connected in series between the AC live wire and the AC neutral wire.

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