Photoelectric-coupler-based power line leakage current detection interrupter and electric appliance

Abstract

Disclosed in the present invention is a photoelectric-coupler-based power line leakage current detection interrupter. The interrupter comprises: a switch unit, which is arranged between an input end and an output end and is used for controlling the connection or disconnection between the input end and the output end; an electric-leakage detection line, which is sheathed in a power line connected between the switch unit and the output end and is used for detecting whether there is a leakage current in the power line; and an electric-leakage protection unit, which is connected to both 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 on the basis of the electric-leakage signal. The photoelectric-coupler-based power line leakage current detection interrupter performs electric-leakage detection by means of photoelectric signal conversion by a photoelectric coupler, and has advantages, such as a simple circuit structure and low costs; moreover, the photoelectric-coupler-based power line leakage current detection interrupter has automatic detection and manual electric-leakage detection functions, and the double electric-leakage detection function effectively improves the safety of a product.

Description

Power line leakage current optocoupler detection protection device and electrical appliances Technical Field

[0001] The present invention relates to the electrical field, and in particular to a power line leakage current optocoupler detection and protection device and an electrical appliance. Background Art

[0002] The power cord leakage current detection and protection device (hereinafter referred to as LCDI) is an electrical fire safety device. Its main structure is a power cord with a plug. Its main function is to detect leakage current between the live and neutral wires of the power cord and the wire shield between the power plug and the load electrical device, such as air conditioners and dehumidifiers. It then cuts off power to the electrical equipment, preventing fires and providing safety protection. It prevents arc fault fires caused by damage to the live, neutral, and ground wires due to aging, wear, compression, or animal chewing, as well as reduced insulation strength.

[0003] Therefore, there is an urgent need for a power line leakage current detection and protection device that can detect the leakage detection line.

[0004] Summary of the Invention

[0005] The present invention proposes to automatically detect the power line through an optocoupler leakage detection module and to add a test unit to manually test the power line, thereby improving the safety of the power line leakage current detection and protection device.

[0006] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a power line leakage current optocoupler detection and protection device, comprising: a switch unit arranged between an input terminal and an output terminal, for controlling the power on or off of the input terminal and the output terminal;

[0007] The leakage detection line is provided to cover the power line connected between the switch unit and the output terminal, and is used to detect whether there is leakage current on the power line;

[0008] The leakage protection unit is connected to the switch unit and the leakage detection line respectively, and is used to detect a leakage signal of the leakage detection line and send a corresponding control signal to the switch unit according to the leakage signal.

[0009] As a further solution of the present invention, the leakage protection unit includes an optocoupler leakage detection module and a switch driving module;

[0010] One path of the optocoupler leakage detection module is connected to the leakage detection line, and the other path is connected to the switch driving module;

[0011] The optocoupler leakage detection module is used to generate and send a control signal to the switch driving module when detecting a leakage signal from the leakage detection line;

[0012] The control end of the switch driving module is electrically connected to the switch unit. The switch driving module is used to generate the corresponding control signal according to the leakage signal to control the switch unit to be disconnected.

[0013] As a further embodiment of the present invention, the present invention further includes a test unit connected between the input terminal and the output terminal and connected to the leakage detection line, wherein the test unit is configured to inject current into the leakage detection line in a conducting state;

[0014] The leakage detection line is further used to generate a leakage signal according to the injected current.

[0015] 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 a photocoupler U1;

[0016] 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 circuit;

[0017] 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 after passing through the eleventh resistor R11;

[0018] The output end of the second rectifier D2 is connected to the photoelectric coupler U1 through the fourth resistor R4.

[0019] As a further solution of the present invention, 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;

[0020] 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;

[0021] The photocoupler U1 is connected between the fifth resistor R5 and the sixth resistor R6 of the static circuit on one path, and 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 photocoupler U1 is triggered;

[0022] 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;

[0023] The trigger circuit is used to trigger the thyristor SCR to turn on.

[0024] As a further solution of the present invention, the test unit includes a test switch, an additional signal line and a twelfth resistor R0;

[0025] 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. The leakage detection line is connected between the test switch TEST and the twelfth resistor R0.

[0026] As a further solution of the present invention, it also includes a plug part and a power cord, wherein the power cord is externally connected to the plug part.

[0027] The plug portion is used to install the switch unit, the leakage protection unit and the test unit;

[0028] 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 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.

[0029] As a further solution of the present invention, the plug portion is further provided with a test switch TEST button and a reset switch RESET button.

[0030] As a further solution of the present invention, the plug portion is further provided with a start indicator light, which is connected to the power supply circuit.

[0031] The present invention also provides an electrical appliance with a power line leakage current optocoupler detection and protection device.

[0032] The beneficial effects of the present invention are as follows: through the implementation of the technical solution of the present invention, the power line leakage current optocoupler detection protection device performs leakage detection through the photoelectric signal conversion of the optocoupler, and has the advantages of simple circuit structure and low cost;

[0033] At the same time, this power line leakage current optocoupler detection protection device has automatic detection and manual leakage detection functions. The dual leakage detection function effectively improves the safety of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG1 is a schematic diagram of a power line leakage current optocoupler detection and protection device according to the present invention;

[0035] FIG2 is a schematic diagram of a power line leakage current optocoupler detection protection device according to the present invention;

[0036] 3 is a schematic structural diagram of a power line leakage current detection and protection device according to the present invention;

[0037] FIG4 is a partially enlarged schematic diagram of a power line leakage current detection and protection device according to the present invention; DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0039] Example 1

[0040] The present invention aims to provide a power line leakage current optocoupler detection and protection device, which has automatic detection and manual leakage detection functions.

[0041] Specifically, the leakage protection unit 104 of the device includes an optocoupler leakage detection module 104b and a switch drive module 104a. The leakage protection unit 104 is used to detect and monitor whether the leakage detection line in the power line 2 is open. When the leakage detection line in the power line 2 is open, the device will automatically cut off the power supply, thereby providing safety protection for electrical appliances.

[0042] Specifically, the manual leakage detection function can detect whether the device has cut off the power supply by manually operating the test switch to close and forcibly energizing the leakage detection line 26.

[0043] As shown in Figures 3 and 4, the power line leakage current optocoupler detection and protection device of the present invention includes a plug part 1 and a power line 2. The inner cavity of the plug part 1 is used to install the switch unit 103, the leakage protection unit 104 and the circuit module integrated with the test unit; the power line 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 constitute an external power supply line 2, the power supply line 2 is externally connected to the plug part 1, and is used to supply power to the electrical appliance; the plug part 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 to test the switch of the circuit, the reset switch RESET3 button is used to start and the relationship between the power line leakage current optocoupler detection protection device, and the start indicator light 5 is used to display whether the power line leakage current optocoupler detection protection device is started.

[0044] As shown in Figures 1 and 2, the power line leakage current optocoupler detection protection device includes:

[0045] The switch unit 103 is provided between the input terminal 101 and the output terminal 102 and is used to control the power on or off of the input terminal 101 and the output terminal 102;

[0046] A leakage detection line 26 is provided to cover the power line connected between the switch unit 103 and the output terminal 102, and is used to detect 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 line. The leakage detection line 26 can also be a meshed copper wire wrapped around other conductors of the power line;

[0047] The leakage protection unit 104 is connected to the switch unit 103 and the leakage detection line 26 respectively, 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;

[0048] Specifically, the leakage protection unit 104 includes an optocoupler leakage detection module 104b and a switch driving module 104a.

[0049] 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.

[0050] The optocoupler leakage detection module 104b is used to generate and send a control signal to the switch driving module 104a when detecting a leakage signal from the leakage detection line 26;

[0051] The control end of the switch driving module 104 a is electrically connected to the switch unit 103 . The switch driving module 104 a is configured to generate the corresponding control signal according to the leakage signal to control the switch unit to be disconnected.

[0052] Specifically, the optocoupler 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 a photocoupler U1;

[0053] 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 circuit;

[0054] 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 after passing through the eleventh resistor R11;

[0055] The output end of the second rectifier D2 is connected to the photoelectric coupler U1 through the fourth resistor R4;

[0056] When the optocoupler leakage detection module 104 b is not triggered, the ninth resistor R9 and the eleventh resistor R11 prevent the voltage input to the second rectifier D2 from triggering the optocoupler U1 .

[0057] When the optocoupler leakage detection module 104 b is triggered, the signal of the leakage detection line 26 triggers the second rectifier D2 of the optocoupler leakage detection module 104 b , thereby driving the input end of the photocoupler U1 to emit light.

[0058] The optocoupler leakage detection module 104 b at least includes a ninth resistor R9 , an eleventh resistor R11 , a second rectifier D2 , a fourth resistor R4 , and a photocoupler U1 to form a detection circuit of the optocoupler leakage detection module 104 b .

[0059] Specifically, the voltage regulator tube ZD2 may be additionally provided between the first output end of the second rectifier D2 and the input end of the photoelectric coupler U1 to achieve voltage stabilization and protect the photoelectric coupler U1.

[0060] Specifically, the input end of the photocoupler U1 is coupled to the photocoupler leakage detection module 104b, and the output end of the photocoupler U1 is coupled to the switch driving module 104a. The photocoupler U1 drives the switch driving module 104a through photoelectric signal conversion to control the switch unit 103 to be disconnected.

[0061] Specifically, the switch driving module 104a 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;

[0062] 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;

[0063] The photocoupler U1 is connected between the fifth resistor R5 and the sixth resistor R6 of the static circuit on one path, and 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 photocoupler U1 is triggered;

[0064] 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;

[0065] The trigger circuit is used to trigger the thyristor SCR to turn on.

[0066] When the output end of the photocoupler U1 is not triggered, the L line connects 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.

[0067] When the output end of the photoelectric coupler U1 is triggered, the L line connects the solenoid SOL, the first rectifier D1, the fifth resistor R5, the photoelectric coupler U1, the first resistor R1, the second resistor R2 and the ground to form a trigger circuit, which triggers the thyristor SCR to turn on. The thyristor SCR is connected in parallel to the second power-on circuit, and at the moment of conduction, the first rectifier D1 is short-circuited, thereby triggering the solenoid SOL to generate a large current and form a sufficiently large magnetic field, causing the switch unit 103 to trip, thereby cutting off the power supply.

[0068] 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 photocoupler U1, the first resistor R1, the second resistor R2, the sixth resistor R6 and the thyristor SCR to form the switch driving module driving circuit.

[0069] Specifically, it further includes a test unit, which is connected between the input end and the output end and connected to the leakage detection line, and is used to inject current into the leakage detection line 26 in a conducting state;

[0070] The leakage detection line 26 is also used to generate a leakage signal according to the injected current. When the test unit is turned on, the switch driving module 104a controls the switch unit 103 according to the leakage signal on the leakage detection line 26 detected by the optocoupler leakage detection module 104b.

[0071] Specifically, the test unit includes a test switch TEST4 and a twelfth resistor R0; the input end L line is connected to the input end 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.

[0072] 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 emitting light to the input end of the driving photocoupler U1, triggering the output end of the photocoupler U1, thereby driving the thyristor SCR to turn on, causing the first rectifier D1 of the switch driving module 104a to be short-circuited instantaneously, so that the solenoid SOL will generate a large current and form a sufficiently large magnetic field, causing the switch unit 103 to trip, thereby cutting off the power supply. By manually closing the test switch, it is possible to detect whether the device has cut off the power supply.

[0073] It can be seen that the ways of triggering the photoelectric coupler U1 of the photoelectric coupling leakage detection module 104b to emit light include:

[0074] The damage of the power line 2 causes the leakage detection line 26 to form a current, triggering the optocoupler leakage detection module 104b, thereby lighting up the driving photocoupler U1;

[0075] The power line is tested manually and the leakage detection line 26 is energized by actively turning on the test unit to generate a current that triggers the optocoupler leakage detection module 104b and thus lights up the driving photocoupler U1.

[0076] By implementing the technical solution of the present invention, the power line leakage current optocoupler detection protection device has automatic detection and manual leakage detection functions, and the dual leakage detection function effectively improves the safety of the product.

[0077] Example 2

[0078] The present invention aims to provide a second power line leakage current optocoupler detection protection device, which performs leakage detection on the power line through the photoelectric signal conversion function of the optocoupler.

[0079] Specifically, the leakage protection unit 104 of the device includes an optocoupler leakage detection module and a switch drive 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 electrical appliances.

[0080] Another power line leakage current optocoupler detection protection device disclosed in this technical solution,

[0081] The switch unit 103 is provided between the input terminal 101 and the output terminal 102 and is used to control the power on or off of the input terminal 101 and the output terminal 102;

[0082] A leakage detection line 26 is provided to cover the power line connected between the switch unit 103 and the output terminal 102, and is used to detect whether there is leakage current on the power line. The leakage detection line 26 can be provided at any position of the power line. The leakage detection line 26 is used to detect whether there is leakage current on the power line;

[0083] The leakage protection unit 104 is connected to the switch unit 103 and the leakage detection line 26 respectively, 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;

[0084] Specifically, the leakage protection unit 104 includes an optocoupler leakage detection module 104b and a switch driving module 104a.

[0085] 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.

[0086] The optocoupler leakage detection module 104b is used to generate and send a control signal to the switch driving module 104a when detecting a leakage signal from the leakage detection line 26;

[0087] The control end of the switch driving module 104 a is electrically connected to the switch unit 103 . The switch driving module 104 a is configured to generate the corresponding control signal according to the leakage signal to control the switch unit to be disconnected.

[0088] Specifically, the switch unit 103 , the leakage detection line 26 , and the leakage protection unit 104 have the same structure and function as those in the first embodiment.

[0089] The working principle of this power line leakage current optocoupler detection protection device is: when the power line 2 is damaged, the leakage detection line 26 forms a current path, triggering the optocoupler leakage detection module 104b.

[0090] By implementing the technical solution of the present invention, the power line leakage current optocoupler detection protection device performs leakage detection through photoelectric signal conversion of the optocoupler, and has the advantages of simple circuit structure and low cost.

[0091] Example 3

[0092] An electrical appliance with a power line leakage current optocoupler detection and protection device includes the power line leakage current optocoupler detection and protection device described in any of the above embodiments. The electrical appliance can be an air conditioner, heater, dehumidifier, refrigerator or other household appliances.

[0093] By implementing the technical solution of the present invention, an electrical appliance with a power line leakage current optocoupler detection protection device is provided with a dual leakage detection function, thereby improving safety.

[0094] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. Power line leakage current optocoupler detection protection device, characterized in that: include: The switch unit is provided between the input terminal and the output terminal, and is used to control the power on or off of the input terminal and the output terminal; A leakage detection line is provided, which is wrapped around the power line connected between the switch unit and the output terminal, 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 and 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 optocoupler leakage detection module is connected to the leakage detection line on one side and connected to the switch driving module on the other side, and is used to generate and send 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 and 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 is 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 and protection device according to claim 3, characterized in that: The optocoupler 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 circuit; 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 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 and 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 photoelectric coupler 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 on one path, and 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 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 and 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. The leakage detection line is connected between the test switch TEST and the twelfth resistor R0.

7. The power line leakage current optocoupler detection and 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 portion is used to install the switch unit, the leakage protection unit and the test unit; 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 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 and protection device according to claim 7, characterized in that: The plug portion is further provided with a test switch TEST button and a reset switch RESET button.

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