Power line leakage current optocoupler detection protection device and electric appliance

Abstract

The utility model discloses a power line leakage current optocoupler detection protection device and an electric appliance, and the device comprises a switch unit which is disposed between an input end and an output end, and is used for controlling the power-on or power-off of the input end and the output end; the electric leakage detection line wraps a power line connected between the switch unit and the output end and is used for detecting whether leakage current exists on the power line or not; the electric leakage protection unit is connected with the switch unit and the electric leakage detection line and is used for detecting an electric leakage signal of the electric leakage detection line and sending a corresponding control signal to the switch unit according to the electric leakage signal. The power line leakage current optocoupler detection protection device performs electric leakage detection through photoelectric signal conversion of the photoelectric coupler, and has the advantages of simple circuit structure, low cost and the like; meanwhile, the power line leakage current optocoupler detection protection device has automatic detection and manual electric leakage detection functions, and the double electric leakage detection functions effectively improve the safety of the product.

Description

Technical Field

[0001] The utility model relates to the field of electricity, in particular to an optocoupler detection and protection device for leakage current of a power cord and an electrical appliance. Background Art

[0002] The leakage current detection and protection device of the power cord, hereinafter referred to as LCDI, is an electrical fire safety protection device. Its main structure is a power cord with a plug. Its main function is to detect the leakage current between the live wire, neutral wire, etc. of the power cord from the power supply plug to the load electrical appliance such as an air conditioner or a dehumidifier and the shielding of the wire protective layer, cut off the power supply of the electrical equipment, prevent the occurrence of a fire, and provide safety protection. It can prevent the power cord damage caused by the aging, wear, extrusion or animal gnawing of the live wire, neutral wire and ground wire in the power cord, and prevent the arc fault fire caused by the decrease of the insulation strength.

[0003] Therefore, there is an urgent need for a leakage current detection and protection device for a power cord that can detect the leakage detection wire. Summary of the Utility Model

[0004] The utility model proposes to automatically detect the power cord through an optocoupler leakage detection module, and add a test unit to manually test the power cord, so as to improve the safety of the leakage current detection and protection device of the power cord.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme: An optocoupler detection and protection device for leakage current of a power cord, comprising: A switch unit is arranged between the input end and the output end, and is used to control the energization or power-off of the input end and the output end;

[0006] The leakage detection wire is coated with a power cord connected between the switch unit and the output end, and is used to detect whether there is leakage current on the power cord;

[0007] The leakage protection unit is respectively connected to the switch unit and the leakage detection wire, and is used to detect the leakage signal of the leakage detection wire, and send a corresponding control signal to the switch unit according to the leakage signal.

[0008] As a further scheme of the utility model, the leakage protection unit includes an optocoupler leakage detection module and a switch driving module;

[0009] One path of the optocoupler leakage detection module is connected to the leakage detection wire, and the other path is connected to the switch driving module;

[0010] The optocoupler leakage detection module is used to generate and send a control signal to the switch driving module when detecting the leakage signal of the leakage detection wire;

[0011] The control terminal of the switch driving module is electrically connected to the switch unit. The switch driving module is configured to generate the corresponding control signal according to the leakage signal to control the switch unit to turn off.

[0012] As a further solution of the present invention, it further includes a test unit. The test unit is connected between the input terminal and the output terminal and is connected to the leakage detection line. The test unit is configured to inject current into the leakage detection line in the conduction state;

[0013] The leakage detection line is further configured to generate a leakage signal according to the injected current.

[0014] As a further solution of the present invention, the optocoupler leakage detection module includes a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a second rectifier D2, a fourth resistor R4, and an optocoupler U1;

[0015] One path of the input terminal L line is connected to the input terminal N line through the ninth resistor R9 and the tenth resistor R10 to form a voltage regulating circuit;

[0016] The first input terminal of the second rectifier D2 is connected to the voltage regulating circuit, and the other path of the input terminal L line is connected to the second input terminal of the second rectifier D2 through the eleventh resistor R11;

[0017] One path of the output terminal of the second rectifier D2 is connected to the optocoupler U1 through the fourth resistor R4.

[0018] As a further solution of the present invention, the switch driving module includes a solenoid SOL, a first rectifier D1, a fifth resistor R5, an optocoupler U1, a first resistor R1, a sixth resistor R6, and a thyristor SCR;

[0019] One path of the input terminal L line is grounded through the solenoid SOL, the first rectifier D1, the fifth resistor R5, and the sixth resistor R6 to form a static circuit; the static circuit is the circuit of the current when the optocoupler U1 is not triggered;

[0020] One path of the optocoupler U1 is connected between the fifth resistor R5 and the sixth resistor R6 of the static circuit, and the other path is connected to the gate of the thyristor SCR through the first resistor R1 to form a trigger circuit; the trigger circuit is the circuit of the current when the optocoupler U1 is triggered;

[0021] The anode of the thyristor SCR is connected to the front end of the fifth resistor R5 of the static circuit, the gate of the thyristor SCR is connected to the trigger circuit, and the cathode of the thyristor SCR is grounded;

[0022] The trigger circuit is configured to trigger the thyristor SCR to conduct.

[0023] As a further solution of the present utility model, the test unit includes a test switch, an additional signal line, and a twelfth resistor R0;

[0024] One path of the input terminal L line passes through the test switch TEST, the additional signal line, and the twelfth resistor R0 to access the input terminal N line to form a test loop, and the leakage detection line is connected between the test switch TEST and the twelfth resistor R0.

[0025] As a further solution of the present utility model, it further includes a plug head and a power cord. The power cord is externally connected to the plug head.

[0026] The plug head is used to install the switch unit, the leakage protection unit, and the test unit;

[0027] The power cord includes an insulating protective layer, a metal outer layer, a live wire L, a neutral wire N, a ground wire G, a leakage detection line, an additional signal line, and a twelfth resistor R0. The insulating protective layer wraps the metal outer layer, and the metal outer layer wraps the live wire L, the neutral wire N, the ground wire G, the leakage detection line, the additional signal line, and the twelfth resistor R0.

[0028] As a further solution of the present utility model, the plug head is further provided with a test switch TEST button and a reset switch RESET button.

[0029] As a further solution of the present utility model, the plug head is further provided with a start indicator light, and the start indicator light is connected to the power supply circuit.

[0030] The present utility model also proposes an electrical appliance with a power cord leakage current opto-coupler detection protection device.

[0031] The beneficial effects of the present utility model are as follows: Through the implementation of the technical solution of the present utility model, this power cord leakage current opto-coupler detection protection device performs leakage detection through the photoelectric signal conversion of the opto-coupler, and has the advantages of simple circuit structure and low cost;

[0032] At the same time, this power cord leakage current opto-coupler detection protection device has automatic detection and manual leakage detection functions, and the dual leakage detection functions effectively improve the safety of the product. Description of the Drawings

[0033] Figure 1 It is the architecture diagram of the power cord leakage current opto-coupler detection protection device of the present utility model;

[0034] Figure 2 It is the schematic diagram of the power cord leakage current opto-coupler detection protection device of the present utility model;

[0035] Figure 3 It is a schematic structural diagram of the leakage current detection and protection device for the power cord of the present utility model;

[0036] Figure 4 It is a partially enlarged schematic diagram of the leakage current detection and protection device for the power cord of the present utility model; Specific embodiments

[0037] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments.

[0038] Embodiment 1

[0039] The present utility model aims to propose an optocoupler detection and protection device for the leakage current of a power cord, and this device has automatic detection and manual leakage detection functions.

[0040] Specifically, the leakage protection unit 104 of this device includes an optocoupler leakage detection module 104b and a switch driving module 104a. The leakage protection unit 104 is used to detect and monitor whether the leakage detection line in the power cord 2 is open. When the leakage detection line in the power cord 2 is open, this device will automatically cut off the power supply, thereby providing safety protection for the electrical appliance.

[0041] Specifically, the manual leakage detection function can be realized by manually operating the test switch to close and forcing the leakage detection line 26 to be energized to detect whether this device cuts off the power supply.

[0042] As Figures 3 - 4 shown, the optocoupler detection and protection device for the leakage current of the power cord of the present utility model includes a plug head 1 and a power cord 2. The inner cavity of the plug head 1 is used to install the circuit module integrated with the switch unit 103, the leakage protection unit 104 and the test unit; the power cord includes a live wire L21, a neutral wire N22, a ground wire G23, a metal outer layer 24 and an insulating protective layer 25, a leakage detection line 26, an additional signal line 27 and a twelfth resistor R0. The insulating protective layer 25 wraps the metal outer layer 24, and the metal outer layer 24 wraps the live wire L21, the neutral wire N22, the ground wire G23, the leakage detection line 26, the additional signal line 27 and the twelfth resistor R0 to form an external power cord 2. The power cord 2 is externally connected to the plug head 1 for supplying power to the electrical appliance; the plug head 1 is also provided with a test switch TEST4 button, a reset switch RESET3 button and a start indicator light 5; the test switch TEST4 button is used for the switch of the test loop, the reset switch RESET3 button is used for the start and connection of the optocoupler detection and protection device for the leakage current of the power cord, and the start indicator light 5 is used to indicate whether the optocoupler detection and protection device for the leakage current of the power cord is started.

[0043] As Figures 1 - 2 shown, the power line leakage current opto - coupler detection and protection device includes:

[0044] A switch unit 103, arranged between the input terminal 101 and the output terminal 102, for controlling the power - on or power - off of the input terminal 101 and the output terminal 102;

[0045] A leakage detection line 26, which is arranged to cover the power line connected between the switch unit 103 and the output terminal 102, for detecting whether there is leakage current on the power line. The leakage detection line 26 is a bare copper wire. The leakage detection line 26 is used to detect whether there is leakage current on the power supply line. The leakage detection line 26 can also be a mesh copper wire wrapped around other wires of the power line;

[0046] A leakage protection unit 104 is respectively connected to the switch unit 103 and the leakage detection line 26, for detecting the leakage signal of the leakage detection line 26 and sending a corresponding control signal to the switch unit 103 according to the leakage signal;

[0047] Specifically, the leakage protection unit 104 includes an opto - coupler leakage detection module 104b and a switch driving module 104a.

[0048] One path of the opto - coupler leakage detection module 104b is connected to the leakage detection line 26, and the other path is connected to the switch driving module 104a.

[0049] The opto - coupler leakage detection module 104b is used to generate and send a control signal to the switch driving module 104a when detecting the leakage signal of the leakage detection line 26;

[0050] The control end of the switch driving module 104a is electrically connected to the switch unit 103. The switch driving module 104a is used to generate the corresponding control signal according to the leakage signal and control the switch unit to disconnect.

[0051] Specifically, the opto - coupler leakage detection module 104b includes a ninth resistor R9, a tenth resistor R10 、 an eleventh resistor R11, a second rectifier D2, a fourth resistor R4 and an opto - coupler U1;

[0052] One path of the input terminal L line is connected to the input terminal N line through the ninth resistor R9 and the tenth resistor R10 to form a voltage - regulating circuit;

[0053] The first input terminal of the second rectifier D2 is connected to the voltage - regulating circuit, and the other path of the input terminal L line is connected to the second input terminal of the second rectifier D2 through the eleventh resistor R11;

[0054] One path of the output terminal of the second rectifier D2 is connected to the optocoupler U1 after passing through the fourth resistor R4;

[0055] When the optocoupler leakage detection module 104b is not triggered, the ninth resistor R9 and the eleventh resistor R11 make the voltage input to the second rectifier D2 not trigger the optocoupler U1.

[0056] When the optocoupler leakage detection module 104b is triggered, the leakage detection line 26 signals to trigger the second rectifier D2 of the optocoupler leakage detection module 104b, thereby driving the input end of the optocoupler U1 to emit light.

[0057] The optocoupler leakage detection module 104b at least includes a ninth resistor R9, an eleventh resistor R11, a second rectifier D2, a fourth resistor R4, and an optocoupler U1 to form a detection circuit of the optocoupler leakage detection module 104b.

[0058] Specifically, a ZD2 voltage stabilizing diode can be added between the first output terminal of the second rectifier D2 and the input terminal of the optocoupler U1 to achieve voltage stabilization and protection of the optocoupler U1.

[0059] Specifically, the input terminal of the optocoupler U1 is coupled to the optocoupler leakage detection module 104b, the output terminal of the optocoupler U1 is coupled to the switch driving module 104a, and the optocoupler U1 drives the switch driving module 104a through photoelectric signal conversion to control the switch unit 103 to disconnect.

[0060] Specifically, the switch driving module 104a includes a solenoid SOL, a first rectifier D1, a fifth resistor R5, an optocoupler U1, a first resistor R1, a sixth resistor R6, and a thyristor SCR;

[0061] One path of the input terminal L line is grounded after passing through the solenoid SOL, the first rectifier D1, the fifth resistor R5, and the sixth resistor R6 to form a static circuit; the static circuit is the circuit of the current when the optocoupler U1 is not triggered;

[0062] One path of the optocoupler U1 is connected between the fifth resistor R5 and the sixth resistor R6 of the static circuit, and the other path is connected to the gate of the thyristor SCR after passing through the first resistor R1 to form a trigger circuit; the trigger circuit is the circuit of the current when the optocoupler U1 is triggered;

[0063] The anode of the thyristor SCR is connected to the front end of the fifth resistor R5 of the static circuit, the gate of the thyristor SCR is connected to the trigger circuit, and the cathode of the thyristor SCR is grounded;

[0064] The trigger circuit is used to trigger the thyristor SCR to conduct.

[0065] When the output end of the optocoupler U1 is not triggered, the L line is connected to the solenoid SOL, the first rectifier D1, the fifth resistor R5, the sixth resistor R6 and the ground to form the static circuit, and the solenoid SOL will not be triggered.

[0066] When the output end of the optocoupler U1 is triggered, the L line is connected to the solenoid SOL, the first rectifier D1, the fifth resistor R5, the optocoupler U1, the first resistor R1, the second resistor R2 and the ground to form a trigger circuit, triggering the thyristor SCR to conduct. The thyristor SCR is connected in parallel with the second energizing circuit and shorts the first rectifier D1 at the moment of conduction, thereby triggering the solenoid SOL to generate a large current, forming a large enough magnetic field, causing the switch unit 103 to trip, and then cutting off the power supply.

[0067] Specifically, the switch driving module 104a at least includes the solenoid SOL, the first rectifier D1, the fifth resistor R5, the output end of the optocoupler U1, the first resistor R1, the second resistor R2, the sixth resistor R6 and the thyristor SCR to form the driving circuit of the switch driving module.

[0068] Specifically, it further includes a test unit. The test unit is connected between the input end and the output end and is connected to the leakage detection line. The test unit is used to inject current into the leakage detection line 26 in the conduction state.

[0069] The leakage detection line 26 is further used to generate a leakage signal according to the injected current. When the test unit is conducting, the switch driving module 104a controls the switch unit 103 according to the leakage signal detected by the optocoupler leakage detection module 104b on the leakage detection line 26.

[0070] Specifically, the test unit includes a test switch TEST4 and a twelfth resistor R0; one path of the input end L line passes through the test switch TEST, an additional signal line, and the twelfth resistor R0 to access the input end N line to form a test circuit, and the leakage detection line is connected between the test switch TEST and the twelfth resistor R0.

[0071] When the test switch TEST4 is closed, the test circuit is turned on to actively energize the leakage detection line 26. The leakage signal of the leakage detection line 26 triggers the second rectifier D2 of the optocoupler leakage detection module 104b, thereby causing the input end of the driving optocoupler U1 to emit light, triggering the output end of the optocoupler U1, and then driving the thyristor SCR to conduct. As a result, the first rectifier D1 of the switch driving module 104a is instantaneously short-circuited, and thus a relatively large current is generated in the solenoid SOL, forming a sufficiently large magnetic field, causing the switch unit 103 to trip, and then cutting off the power supply. By operating the manual closing test switch, it is possible to detect whether the device cuts off the power supply.

[0072] It can be seen from this that the ways to trigger the optocoupler U1 of the optocoupler leakage detection module 104b to emit light include:

[0073] The breakage of the power line 2 causes a current to be formed in the leakage detection line 26, triggering the optocoupler leakage detection module 104b, thereby lighting up the driving optocoupler U1;

[0074] Manually and actively test the power line. By actively turning on the test unit to energize the leakage detection line 26 to form a current, the optocoupler leakage detection module 104b is triggered, thereby lighting up the driving optocoupler U1.

[0075] By implementing the technical solution of the present invention, this kind of optocoupler detection and protection device for power line leakage current has automatic detection and manual leakage detection functions, and the dual leakage detection functions effectively improve the safety of the product.

[0076] Embodiment 2

[0077] The present invention aims to propose a second optocoupler detection and protection device for power line leakage current, which detects the leakage current of the power line through the opto - electrical signal conversion function of the optocoupler.

[0078] Specifically, the leakage protection unit 104 of the device includes an optocoupler leakage detection module and a switch driving module. The leakage protection unit 104 is used to detect and monitor whether the leakage detection line in the power line is open. When the leakage detection line in the power line is open, the device will automatically cut off the power supply, thereby providing safety protection for the electrical appliance.

[0079] Another optocoupler detection and protection device for power line leakage current disclosed in this technical solution

[0080] A switch unit 103 is arranged between the input end 101 and the output end 102, and is used to control the energization or power - off of the input end 101 and the output end 102;

[0081] The leakage detection line 26 is provided in a wrapped manner with the power supply line connected between the switch unit 103 and the output terminal 102, and is used to detect whether there is a leakage current on the power supply line. The leakage detection line 26 can be arranged at any position of the power cord, and the leakage detection line 26 is for detecting whether there is a leakage current on the power supply line;

[0082] The leakage protection unit 104 is respectively connected to the switch unit 103 and the leakage detection line 26, and is used to detect the leakage signal of the leakage detection line 26 and send a corresponding control signal to the switch unit 103 according to the leakage signal;

[0083] Specifically, the leakage protection unit 104 includes an optocoupler leakage detection module 104b and a switch driving module 104a.

[0084] One path of the optocoupler leakage detection module 104b is connected to the leakage detection line 26, and the other path is connected to the switch driving module 104a.

[0085] The optocoupler leakage detection module 104b is used to generate and send a control signal to the switch driving module 104a when detecting the leakage signal of the leakage detection line 26;

[0086] The control end of the switch driving module 104a is electrically connected to the switch unit 103, and the switch driving module 104a is used to generate the corresponding control signal according to the leakage signal and control the switch unit to disconnect.

[0087] Specifically, the structures and functions of the switch unit 103, the leakage detection line 26, and the leakage protection unit 104 are the same as those in the first embodiment.

[0088] The working principle of this kind of power cord leakage current optocoupler detection and protection device: When the damage of the power cord 2 causes the leakage detection line 26 to form a current path and trigger the optocoupler leakage detection module 104b.

[0089] By implementing the technical solution of the present invention, this kind of power cord leakage current optocoupler detection and protection device performs leakage detection through the photoelectric signal conversion of the optocoupler, and has the advantages of simple circuit structure and low cost.

[0090] Embodiment III

[0091] An electrical appliance with a power cord leakage current optocoupler detection and protection device includes the power cord leakage current optocoupler detection and protection device described in any of the above embodiments. The electrical appliance can be household appliances such as air conditioners, heaters, dehumidifiers, refrigerators, etc.

[0092] By implementing the technical solution of the present utility model, the electrical appliance with the optocoupler detection and protection device for the leakage current of the power cord has a dual leakage detection function, and the safety is higher.

[0093] The above is only the preferred specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present utility model, according to the technical solution of the present utility model and its inventive concept, makes equivalent replacements or changes, and should be covered within the protection scope of the present utility model.

Claims

1. Power line leakage current optocoupler detection protection device, characterized in that: include: A switch unit is provided between the input end and the output end, and is used to control the power on or off of the input end and the output end; A leakage detection line is arranged to cover the power line connected between the switch unit and the output end, and is used to detect whether there is leakage current on the power line; The leakage protection unit is connected to the switch unit and the leakage detection line respectively, and is used to detect the leakage signal of the leakage detection line and send a corresponding control signal to the switch unit according to the leakage signal.

2. The power line leakage current optocoupler detection protection device according to claim 1, characterized in that: The leakage protection unit includes an optocoupler leakage detection module and a switch driving module; The optical coupler leakage detection module is connected to the leakage detection line through one path and connected to the switch driving module through another path, and is used for generating and sending a control signal to the switch driving module when a leakage signal of the leakage detection line is detected; The control end of the switch driving module is electrically connected to the switch unit, and is used to generate the corresponding control signal according to the leakage signal to control the switch unit to be disconnected.

3. The power line leakage current optocoupler detection protection device according to claim 1 or 2, characterized in that: Also includes: The test unit is connected between the input terminal and the output terminal and connected to the leakage detection line, and is used to inject current into the leakage detection line in a conducting state.

4. The power line leakage current optocoupler detection protection device according to claim 2, characterized in that: The optical coupler leakage detection module includes a ninth resistor R9 and a tenth resistor R10 、 an eleventh resistor R11, a second rectifier D2, a fourth resistor R4 and a photocoupler U1; The input terminal L line passes through the ninth resistor R9 and the tenth resistor R10 and then connects to the input terminal N line to form a voltage regulation loop; The first input end of the second rectifier D2 is connected to the voltage regulating circuit, and the other path of the input end L line is connected to the second input end of the second rectifier D2 after passing through the eleventh resistor R11; The output end of the second rectifier D2 is connected to the photoelectric coupler U1 through the fourth resistor R4.

5. The power line leakage current optocoupler detection protection device according to claim 4, characterized in that: The switch driving module includes a solenoid SOL, a first rectifier D1, a fifth resistor R5, a photocoupler U1, a first resistor R1, a sixth resistor R6 and a thyristor SCR; The input end L line passes through the solenoid SOL, the first rectifier D1, the fifth resistor R5, the sixth resistor R6 and then is grounded to form a static loop; the static loop is the loop of the current when the photocoupler U1 is not triggered; The photocoupler U1 is connected between the fifth resistor R5 and the sixth resistor R6 of the static circuit in one path, and connected to the gate of the thyristor SCR through the first resistor R1 in another path to form a trigger circuit; the trigger circuit is the circuit of the current when the photocoupler U1 is triggered; The anode of the thyristor SCR is connected to the front end of the fifth resistor R5 of the static circuit, the gate of the thyristor SCR is connected to the trigger circuit, and the cathode of the thyristor SCR is grounded; The trigger circuit is used to trigger the thyristor SCR to turn on.

6. The power line leakage current optocoupler detection protection device according to claim 3, characterized in that: The test unit includes a test switch TEST, an additional signal line and a twelfth resistor R0; The input terminal L line is connected to the input terminal N line through the test switch TEST, the additional signal line, and the twelfth resistor R0 to form a test loop, and the leakage detection line is connected between the test switch TEST and the twelfth resistor R0.

7. The power line leakage current optocoupler detection protection device according to claim 6, characterized in that: It also includes a plug portion and a power cord, wherein the power cord is externally connected to the plug portion; The plug part is used to install the switch unit, the leakage protection unit and the test unit; The power line includes an insulating protective layer, a metal outer layer, a live wire L, a neutral wire N, a ground wire G, a leakage detection wire, an additional signal wire and a twelfth resistor R0, the insulating protective layer wraps the metal outer layer, and the metal outer layer wraps the live wire L, the neutral wire N, the ground wire G, the leakage detection wire, the additional signal wire and the twelfth resistor R0.

8. The power line leakage current optocoupler detection protection device according to claim 7, characterized in that: The plug part is also provided with a test switch TEST button and a reset switch RESET button.

9. The power line leakage current optocoupler detection protection device according to claim 8, characterized in that: The plug portion is also provided with a start indicator light, and the start indicator light is connected to a power supply circuit.

10. An electrical appliance with a power line leakage current optocoupler detection and protection device, characterized in that: include: A power line leakage current detection and protection device as claimed in any one of claims 1 to 9.

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