CN220585967U

CN220585967U - Leakage detection protection device, electric connection equipment and electric appliance

Info

Publication number: CN220585967U
Application number: CN202321691997.0U
Authority: CN
Inventors: 李成力; 陈龙
Original assignee: Suzhou Ele Mfg Co ltd
Current assignee: Suzhou Ele Mfg Co ltd
Priority date: 2023-06-30
Filing date: 2023-06-30
Publication date: 2024-03-12
Anticipated expiration: 2033-06-30

Abstract

The utility model discloses a leakage detection protection device. The apparatus comprises a leakage detection module comprising a first leakage detection line, a second leakage detection line and at least one resistive element and/or at least one semiconductor element and being configured to detect leakage current signals on the first and second current carrying lines and to generate a leakage fault signal upon detection of said leakage current signals, wherein the first and second leakage detection lines are electrically insulated from each other and cover at least one of the first and second current carrying lines, respectively, and wherein the at least one resistive element and/or the at least one semiconductor element is connected in series between the first and second leakage detection lines and forms a current loop for detecting whether the leakage detection module is faulty. The utility model ensures the reliability of the leakage detection protection device by detecting whether the leakage detection line fails.

Description

Leakage detection protection device, electric connection equipment and electric appliance

Technical Field

The utility model relates to the field of electric appliances, in particular to a leakage detection protection device, electric connection equipment and an electric appliance.

Background

The utility model provides a power cord leakage detection protection device (abbreviated as "LCDI device" below) is a kind of safety protection device for electric fire, its main structure is the power cord with plug, and the main function is to detect the leakage current that takes place between power cord live wire, zero line etc. and the wire inoxidizing coating (shielding) between power plug to the load electrical apparatus (for example air conditioner, dehumidifier), and cut off the consumer power, prevent the production of conflagration to provide safety protection. Accordingly, the LCDI device can prevent arc fault fires caused by damage to the power line, a decrease in insulation strength, and the like due to live (L line), neutral (N line), ground wire aging, wear, extrusion, or animal biting among the power lines.

In the existing LCDI device, when the leakage detection line of the live wire or the zero wire in the power line does not have a protection function due to open circuit or disconnection, the product can still work normally, so that fire disaster or other hidden danger of electricity use safety exists.

Therefore, there is a need for an electric leakage detection protection device capable of detecting an electric leakage detection line.

Disclosure of Invention

Based on the above-mentioned problems, a first aspect of the present utility model proposes a leakage detection protection device, comprising: a leakage detection module comprising a first leakage detection line, a second leakage detection line, and at least one resistive element and/or at least one semiconductor element, and configured to detect leakage current signals on the first and second current carrying lines, and to generate a leakage fault signal upon detection of the leakage current signals, wherein,

The first and second leakage detection lines are electrically insulated from each other and respectively cover at least one of the first and second current carrying lines, and the at least one resistive element and/or the at least one semiconductor element is connected in series between the first and second leakage detection lines and forms a current loop for detecting whether the leakage detection module fails.

In some embodiments, the first and second leakage detection lines each have a first end proximate to an input end of the first and second current carrying lines and a second end proximate to an output end of the first and second current carrying lines, and the second end of the first leakage detection line is connected to the second end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

In some embodiments, the first and second leakage detection lines each have a first end proximate to an input of the first and second current carrying lines and a second end proximate to an output of the first and second current carrying lines, and the first end of the first leakage detection line is connected to the second end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

In some embodiments, the first and second leakage detection lines each have a first end proximate to an input of the first and second current carrying lines and a second end proximate to an output of the first and second current carrying lines, and the second end of the first leakage detection line is connected to the first end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

In some embodiments, the first and second leakage detection lines each have a first end proximate to an input of the first and second current carrying lines and a second end proximate to an output of the first and second current carrying lines, and the first end of the first leakage detection line is connected to the first end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

In some embodiments, the at least one resistive element comprises a resistor, a capacitor, an inductor, and/or a wire.

In some embodiments, the at least one semiconductor element comprises a diode, a bipolar transistor, a field effect transistor, and/or a thyristor.

In some embodiments, the leakage detection protection device further comprises: a detection monitoring module coupled to the leakage detection module and configured to detect whether an open circuit fault has occurred in the first and second leakage detection lines via the current loop and to generate an open circuit fault signal when the open circuit fault has occurred.

In some embodiments, the detection monitoring module includes at least one resistor and/or at least one diode.

In some embodiments, the leakage detection protection device further comprises: a switching module configured to control an electrical connection between an input and an output of the first and second current carrying lines; and a drive module coupled to the leakage detection module and/or the detection monitoring module and configured to drive the switch module to disconnect the power connection in response to the leakage fault signal and/or the open circuit fault signal.

In some embodiments, at least one of the first and second leakage detection lines is outboard coated with an insulating structure.

In some embodiments, the insulating structure is integrally formed from plastic or is covered with insulating paper and/or cotton.

In some embodiments, one side of the first and/or second leakage detection lines is an insulating material and the other side is a conductive material.

In some embodiments, the leakage detection protection device further comprises: a test module coupled to the leakage detection module and including a test switch and configured to generate the simulated leakage fault signal via the current loop to detect whether the leakage detection protection device is operating properly when the test switch is operated.

A second aspect of the present utility model proposes an electrical connection device comprising: a housing; and a leakage detection protection device according to any one of the embodiments of the first aspect, the leakage detection protection device being housed in the housing.

A third aspect of the present utility model proposes an electrical appliance comprising: a load device; and an electrical connection device coupled between the power supply line and the load device for supplying power to the load device, wherein the electrical connection device comprises a leakage detection protection apparatus according to any one of the embodiments of the first aspect.

The utility model ensures the reliability of the leakage detection protection device by detecting whether the leakage detection line fails. In addition, the leakage detection protection device provided by the utility model has the advantages of simple circuit structure, low cost and high safety.

Drawings

The embodiments are shown and described with reference to the drawings. The drawings serve to illustrate the basic principles and thus only show aspects necessary for understanding the basic principles. The figures are not to scale. In the drawings, like reference numerals refer to like features. In addition, a connection between each frame in the architecture diagram indicates that there is an electrical coupling between two frames, and the absence of a connection between two frames does not indicate that the two frames are not coupled.

Fig. 1 is a schematic diagram showing a conventional earth leakage detection protection device;

FIG. 2 shows a schematic diagram of a leakage detection protection device according to an embodiment of the present utility model;

fig. 3 shows a schematic diagram of a first embodiment of the earth leakage detection protection device according to the present utility model;

fig. 4 shows a schematic diagram of a second embodiment of the earth leakage detection protection device according to the present utility model;

fig. 5 shows a schematic diagram of a third embodiment of the earth leakage detection protection device according to the present utility model;

fig. 6 shows a schematic diagram of a fourth embodiment of the earth leakage detection protection device according to the present utility model;

fig. 7 shows a schematic diagram of a fifth embodiment of the earth leakage detection protection device according to the present utility model;

FIG. 8 illustrates a cross-sectional view of one embodiment of a power cord of the leakage detection protection device in accordance with the present utility model; and

Fig. 9 shows a cross-sectional view of another embodiment of the power cord of the earth leakage detection protection device according to the present utility model.

Detailed Description

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof. The accompanying drawings illustrate, by way of example, specific embodiments in which the utility model may be practiced. The illustrated embodiments are not intended to be exhaustive of all embodiments according to the utility model. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present utility model. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present utility model is defined by the appended claims.

Before describing embodiments of the present utility model, some of the terms involved in the present utility model will be explained first for better understanding of the present utility model.

The terms "connected," "coupled," or "coupled" and the like as used herein are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "a," "an," "a group," or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one.

The terms "comprising," including, "and similar terms used herein should be construed to be open-ended terms, i.e., including, but not limited to," meaning that other elements may also be included. The term "based on" is based at least in part on. The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment," and so forth. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Fig. 1 shows a schematic diagram of a conventional leakage detection protection device. As shown in fig. 1, the power supply line 2 includes a first current carrying line (e.g., a live line L) 21, a second current carrying line (e.g., a neutral line N) 22, a third current carrying line (e.g., a ground line G) 23, and a leakage detection line 24. When the leakage detection line 24 is not protected by an open circuit or an open circuit, the LCDI device can still function normally, thus presenting a fire hazard or other electrical safety hazard.

The present utility model aims to provide an electric leakage detection protection device in which reliability of the electric leakage detection protection device is ensured by detecting whether or not an electric leakage detection line fails.

Fig. 2 shows a schematic diagram of the earth leakage detection protection device according to the present utility model. As shown in fig. 2, the leakage detection protection device 200 includes a leakage detection module 204. The leakage detection module 204 is disposed between the input terminal 201 and the output terminal 202 of the first current-carrying line 21 and the second current-carrying line 22, and is configured to detect leakage current signals on the first current-carrying line 21 and the second current-carrying line 22, and generate a leakage fault signal when the leakage current signals are detected. The leakage detection module 204 includes a first leakage detection line, a second leakage detection line, and at least one resistive element and/or at least one semiconductor element (not shown in fig. 2). Specifically, the leakage detection module 204 may include more than one resistive element, more than one semiconductor element, or a combination of more than one resistive element and more than one semiconductor element. The resistive element may include, for example, any one or more of a resistor, a capacitor, an inductor, and a wire having a certain resistance. The semiconductor element may include, for example, any one or more of a diode, a bipolar transistor, a field effect transistor, and a silicon controlled rectifier. For example, the leakage detection module 204 may include a resistor and a transistor, may include two resistors, may include an inductor and a diode, may include two diodes, a wire and a transistor, and so on. The first and second leakage detection lines are electrically insulated from each other and cover at least the first and second current-carrying lines, respectively. At least one resistive element and/or at least one semiconductor element is connected in series between the first and second leakage detection lines and forms a current loop for detecting whether the leakage detection module 24 is malfunctioning. The failure of the leakage detection module 204 may include, for example, an open circuit failure of the first leakage detection line and the second leakage detection line. The device 200 ensures the reliability of the leakage detection protection device by detecting whether the leakage detection line fails, and has simple circuit structure, low cost and high safety.

In some embodiments, at least one of the first and second leakage detection lines may be externally coated with an insulating structure such that the first and second leakage detection lines are electrically insulated from each other. The insulation structure can be formed by plastic integrally and is coated on the outer side of the first leakage detection line and/or the outer side of the second leakage detection line. Alternatively, the insulating structure may be insulating paper, insulating cotton or any other insulating material, and is coated on the outer side of the first leakage detection line and/or the second leakage detection line. Instead of providing a separate insulating structure, the first leakage detection line and/or the second leakage detection line may be manufactured using a sheet material having an insulating material on one side (e.g., an outer side) and a conductive material on the other side, thereby achieving electrical insulation between the first leakage detection line and the second leakage detection line.

In some embodiments, the leakage detection protection device 200 may also include a detection monitoring module (not shown in fig. 2). The detection monitoring module is coupled to the leakage detection module, detects whether an open circuit fault occurs in the first leakage detection line and the second leakage detection line via a current loop formed by the first leakage detection line, the at least one resistive element and/or the semiconductor element and the second leakage detection line, and generates an open circuit fault signal when the open circuit fault occurs. The detection monitoring module may comprise at least one resistor and/or at least one diode.

In some embodiments, the leakage detection protection device 200 may also include a switching module and a driving module (not shown in fig. 2). The switching module controls the electrical connection between the input and the output of the first and second current carrying lines. The driving module is coupled to the leakage detection module 204 and/or the detection monitoring module, and drives the switching module to disconnect the power in response to the leakage fault signal and/or the open circuit fault signal, thereby further improving the reliability of the leakage detection protection device 200.

In some embodiments, the leakage detection protection device 200 may also include a test module (not shown in fig. 2). The test module is coupled to the leakage detection module 204 and includes a test switch. The test module generates a simulated leakage fault signal via a current loop formed by the first leakage detection line, the at least one resistive element and/or the semiconductor element and the second leakage detection line when the test switch is operated to detect whether the leakage detection protection device 200 is operating normally, thereby further improving the reliability of the leakage detection protection device 200.

Fig. 3 shows a schematic diagram of a first embodiment of the earth leakage detection protection device according to the present utility model. As shown in fig. 3, the leakage detection protection device 300 includes a switch module 203, a leakage detection module 204, a detection monitoring module 205, a driving module 206, and a testing module 207. The power supply line comprises a first current carrying line 21, a second current carrying line 22 and a ground line 23.

The switching module 203 comprises a reset switch RSET for controlling the power connection between the input LINE and the output LOAD of the first and second current LINEs 21, 22. The leakage detection module 204 includes a first leakage detection line 241, a second leakage detection line 242, and a resistor R7 connected in series between the first leakage detection line 241 and the second leakage detection line 242. In this embodiment, the first end B of the first leakage detection LINE 241 and the first end a of the second leakage detection LINE 242 are ends near the input end LINE, which is located on the left side in fig. 3; the second ends C and D of the first and second leakage detection lines 241 and 242 are ends near the output end LOAD, which is located on the right side in fig. 3.

As shown in fig. 3, the first leakage detection line 241, the resistor R7, and the second leakage detection line 242 are sequentially connected in series. More specifically, the first end B of the first leakage detection line 241 is connected to one end of the resistor R3 of the test module 207 and one end of the resistor R6 of the detection monitor module 205; the second end C of the first leakage detection line 241 is connected to the second end D of the second leakage detection line 242 through a resistor R7; the first end a of the second leakage detection line 242 is connected to one end of the resistor R5 of the detection monitor module 205 and the resistor R2 of the driving module 206. The other end of the resistor R5 is connected to the first current line 21 and to the reset switch RSET of the switching block 207. The other end of resistor R6 is connected to the cathode of the thyristor SCR of the drive module 206. The driving module 206 further includes capacitors C1, C2, a zener diode ZD1, resistors R1, R2, R4, and diodes D1, D2 and a light emitting diode LED. The capacitor C2 is connected in parallel with the resistor R4, then connected to the anode of the zener diode ZD1 and connected to the control electrode of the silicon controlled rectifier SCR. The cathode of the zener diode ZD1 is connected to the other end of the resistor R2 and the capacitor C1. The anode of the thyristor SCR is connected to one end of the solenoid SOL, the other end of which is connected to the second current line 22 and to the reset switch RSET. The anode of the diode D1 is connected to the cathode of the thyristor SCR, the cathode of which is connected to the first current line 21 and to the reset switch RSET. The diode D2 is a common diode of the detection and monitoring module 205 and the driving module 206, and its anode is connected to the cathode of the SCR, and its cathode is connected to the anode of the SCR.

The TEST module 207 includes a resistor R3 and a TEST switch TEST connected in series. The TEST switch TEST is also connected to the first current line 21 and to the reset switch RSET. In this embodiment, the first current carrying line 21, the TEST switch TEST, the resistor R3, the first leakage detection line 241, the resistor R7, the second leakage detection line 242, the resistor R2, the zener diode ZD1, the resistor R4, the diode D2, the solenoid SOL, and the second current carrying line 22 form a TEST circuit.

Under the normal operation condition of the leakage detection protection device 300, current flows through the first current carrying line 21-R5-second leakage detection line 242-R7-first leakage detection line 241-R6-D2-SOL-second current carrying line 22, the voltage at point a is limited to a lower potential, for example, lower than the threshold voltage of the zener diode ZD1, by setting the resistance values of the resistors R5, R6 and R7, so that the voltage of the control electrode of the SCR is limited to an extremely low level, the SCR is not triggered, the switch module 203 is in a closed state, and the device 300 operates normally.

When the first current carrying line 21 has a leakage fault (i.e. a leakage current signal exists), the first leakage detection line 241 is electrified, so that the potential at point a is increased, and when the leakage current on the first current carrying line 21 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the first current carrying line 21, the first leakage detection line 241-R7 and the second leakage detection line 242-R2-ZD1 to trigger the SCR to be conducted. When the SCR is turned on, a trip circuit of the second current-carrying LINE 22-SOL-SCR-D1-first current-carrying LINE 21 is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently large to trip the reset switch RSET, thereby cutting off the power connection between the input terminal LINE and the output terminal LOAD.

When the second current carrying wire 22 has a leakage fault (i.e. a leakage current signal exists), the second leakage detection wire 242 is electrified, so that the potential at the point a is increased, and when the leakage current on the second current carrying wire 22 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the second current carrying wire 22-the second leakage detection wire 242-R2-ZD1 to trigger the SCR to be conducted. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

When either one of the first leakage detection line 241 and the second leakage detection line 242 is opened or disconnected, or both of the two lines are opened or disconnected, the resistors R6 and R7 lose the voltage dividing function, the potential at the point a rises, and the current (i.e. the open fault signal) flows through the first current carrying line 21-R5-R2-ZD1 to trigger the SCR to be turned on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

The leakage detection protection device 300 also has a test function. The fault test of the leakage detection module 204 may be performed by the test module 207. When the TEST switch TEST is closed, i.e. the TEST circuit is a closed loop, a current, i.e. an analog leakage fault signal, flows in the loop of the first current carrying line 21-TEST-R3-first leakage detection line 241-R7-second leakage detection line 242-R2-ZD 1-R4-D2-SOL-second current carrying line 22. The current will cause the voltage across resistor R4 to rise, triggering the SCR to turn on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

If either one of the first leakage detection line 241 and the second leakage detection line 242 is open or broken, or both lines are open or broken, then when the TEST switch TEST is closed, the TEST circuit cannot form a closed loop, no current will flow through the TEST circuit, the SCR cannot be triggered, and the reset switch RSET will not trip. At this time, the user is prompted that at least one of the first leakage detection line 241 and the second leakage detection line 242 may have an open or broken condition. Accordingly, the user can detect whether the first and second leakage detection lines 241 and 242 are intact by operating the TEST switch TEST. It will be appreciated that in addition to detecting a failure of the leakage detection module 204, the test module 207 may also be used to detect whether other components in the test circuit are malfunctioning.

Fig. 4 shows a schematic diagram of a second embodiment of the earth leakage detection protection device according to the present utility model. The difference compared to the embodiment of fig. 3 is mainly that in the leakage detection module 204, the resistor R7 is replaced by diodes D3 and D4.

In the leakage detection protection device 400, an anode of the diode D3 is connected to a cathode of the diode D4 and to the second end D of the second leakage detection line 242; the cathode of the diode D3 is connected to the anode of the diode D4 and to the second terminal C of the first leakage detection line 241.

Under the normal operation condition of the leakage detection protection device 400, current flows through the first current carrying line 21-R5-second leakage detection line 242-D3-first leakage detection line 241-R6-D2-SOL-second current carrying line 22, the voltage at point a is limited to a lower potential, for example, lower than the threshold voltage of the zener diode ZD1, by setting the resistance values of the resistors R5 and R6, so that the voltage of the control electrode of the SCR is limited to an extremely low level, the SCR is not triggered, the switch module 203 is in a closed state, and the device 400 operates normally.

When the first current carrying line 21 has a leakage fault (i.e. a leakage current signal exists), the first leakage detection line 241 is electrified, so that the potential at point a is increased, and when the leakage current on the first current carrying line 21 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the first current carrying line 21, the first leakage detection line 241-D4 and the second leakage detection line 242-R2-ZD1 to trigger the SCR to be conducted. When the SCR is turned on, a trip circuit of the second current-carrying LINE 22-SOL-SCR-D1-first current-carrying LINE 21 is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently large to trip the reset switch RSET, thereby cutting off the power connection between the input terminal LINE and the output terminal LOAD.

When the second current carrying wire 22 has a leakage fault (i.e. a leakage current signal exists), the second leakage detection wire 242 is electrified, so that the potential at the point a is increased, and when the leakage current on the second current carrying wire 22 exceeds a set threshold value, a current (i.e. an open circuit fault signal) flows through the second current carrying wire 22-the second leakage detection wire 242-R2-ZD1 to trigger the SCR to be conducted. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

When either one of the first leakage detection line 241 and the second leakage detection line 242 is opened or disconnected, or both lines are opened or disconnected, the potential at the point a increases, and the current flows through the first current carrying line 21-R5-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

The leakage detection protection device 400 also has a test function. The fault test of the leakage detection module 204 may be performed by the test module 207. When the TEST switch TEST is closed, i.e. the TEST circuit is a closed loop, a current, i.e. an analog leakage fault signal, flows in the loop of the first current carrying line 21-TEST-R3-first leakage detection line 241-D4-second leakage detection line 242-R2-ZD 1-R4-D2-SOL-second current carrying line 22. The current will cause the voltage across resistor R4 to rise, triggering the SCR to turn on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

Fig. 5 shows a schematic diagram of a third embodiment of the earth leakage detection protection device according to the present utility model. Compared to the embodiment of fig. 3, the difference is mainly that the leakage detection module 204 further includes a first signal line 25A and a second signal line 25B. One end of the first signal line 25A is connected to the first end B of the first leakage detection line 241, and the other end is connected to the resistor R7; one end of the second signal line 25B is connected to one ends of the resistor R3 and the resistor R6, and the other end is connected to the second end C of the first leakage detection line 241.

Under the normal operation condition of the leakage detection protection device 500, current flows through the first current carrying line 21-R5-second leakage detection line 242-R7-first signal line 25A-first leakage detection line 241-second signal line 25B-R6-D2-SOL-second current carrying line 22, the voltage at point a is limited to a lower potential, for example, lower than the threshold voltage of the zener diode ZD1, by setting the resistance values of the resistors R5, R6 and R7, so that the voltage of the control electrode of the SCR is limited to an extremely low level, the SCR is not triggered, the switch module 203 is in a closed state, and the device 500 operates normally.

When the first current carrying line 21 has a leakage fault (i.e. a leakage current signal exists), the first leakage detection line 241 is electrified, so that the potential at point a is increased, and when the leakage current on the first current carrying line 21 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the first current carrying line 21-the first leakage detection line 241-the first signal line 25A-R7-the second leakage detection line 242-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, a trip circuit of the second current-carrying LINE 22-SOL-SCR-D1-first current-carrying LINE 21 is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently large to trip the reset switch RSET, thereby cutting off the power connection between the input terminal LINE and the output terminal LOAD.

When any one or more of the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B is opened or closed, the resistors R6 and R7 lose the voltage dividing function, the potential at point a increases, and the current (i.e., the open fault signal) flows through the first current carrying line 21-R5-R2-ZD1 to trigger the SCR to be turned on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

The leakage detection protection device 500 also has a test function. The fault test of the leakage detection module 204 may be performed by the test module 207. When the TEST switch TEST is closed, i.e. the TEST circuit is a closed loop, a current flows in the loop of the first current carrying line 21-TEST-R3-second signal line 25B-first leakage detection line 241-first signal line 25A-R7-second leakage detection line 242-R2-ZD 1-R4-D2-SOL-second current carrying line 22, i.e. the simulated leakage fault signal. The current will cause the voltage across resistor R4 to rise, triggering the SCR to turn on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

If any one or more of the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B is opened or closed, when the TEST switch TEST is closed, the TEST circuit cannot form a closed loop, no current will flow through the TEST circuit, the SCR cannot be triggered, and the reset switch RSET will not trip. At this time, the user is prompted that at least one of the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B may have an open or broken condition. Accordingly, the user can detect whether the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B are intact by operating the TEST switch TEST. It will be appreciated that in addition to detecting a failure of the leakage detection module 204, the test module 207 may also be used to detect whether other components in the test circuit are malfunctioning.

Fig. 6 shows a schematic diagram of a fourth embodiment of the earth leakage detection protection device according to the present utility model. Compared to the embodiment of fig. 3, the difference is mainly that the leakage detection module 204 further includes a first signal line 25A and a second signal line 25B, and the resistor R7 is replaced with a bipolar transistor Q1 (NPN transistor in this embodiment). One end of the first signal line 25A is connected to one ends of the resistors R5 and R2, and the other end is connected to the second end D of the second leakage detection line 242; one end of the second signal line 25B is connected to the first end a of the second leakage detection line 242, and the other end is connected to the emitter of the transistor Q1; the collector of the transistor Q1 is connected to the second terminal C of the first leakage detection line 241.

Under the normal operation condition of the leakage detection protection device 600, current flows through the first current carrying line 21-R5-the first signal line 25A-the second leakage detection line 242-the second signal line 25B-the transistor Q1-the first leakage detection line 241-R6-D2-SOL-the second current carrying line 22, the voltage at the point a is limited to a lower potential, for example, lower than the threshold voltage of the zener diode ZD1, by setting the resistance values of the resistors R5 and R6, so that the voltage of the control electrode of the SCR is limited to an extremely low level, the SCR is not triggered, the switch module 203 is in a closed state, and the device 600 operates normally.

When the first current carrying line 21 has a leakage fault (i.e. a leakage current signal exists), the first leakage detection line 241 is electrified, so that the potential at point a is increased, and when the leakage current on the first current carrying line 21 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the first current carrying line 21, the first leakage detection line 241-Q1, the second signal line 25B, the second leakage detection line 242, and the first signal detection line 25A-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, a trip circuit of the second current-carrying LINE 22-SOL-SCR-D1-first current-carrying LINE 21 is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently large to trip the reset switch RSET, thereby cutting off the power connection between the input terminal LINE and the output terminal LOAD.

When the second current carrying wire 22 has a leakage fault (i.e. a leakage current signal exists), the second leakage detection wire 242 is electrified, so that the potential at the point a is increased, and when the leakage current on the second current carrying wire 22 exceeds a set threshold value, a current (i.e. the leakage fault signal) flows through the second current carrying wire 22, the second leakage detection wire 242 and the first signal wire 25A-R2-ZD1 to trigger the SCR to be conducted. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

When any one or more of the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B is opened or closed, the potential at point a increases, and a current (i.e., an open fault signal) flows through the first current carrying line 21-R5-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

The leakage detection protection device 600 also has a test function. The fault test of the leakage detection module 204 may be performed by the test module 207. When the TEST switch TEST is closed, i.e. the TEST circuit is a closed loop, a current flows in the loop of the first current carrying line 21-TEST-R3-first leakage detection line 241-Q1-second signal line 25B-second leakage detection line 242-first signal line 25A-R2-ZD 1-R4-D2-SOL-second current carrying line 22, i.e. the simulated leakage fault signal. The current will cause the voltage across resistor R4 to rise, triggering the SCR to turn on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

Fig. 7 shows a schematic diagram of a fifth embodiment of the earth leakage detection protection device according to the present utility model. The main difference compared to the embodiment of fig. 3 is that the leakage detection module 204 further comprises a first signal line 25A and a second signal line 25B, and that the resistor R7 is replaced by diodes D1 and D2, and that the diodes D1 and D2 are replaced by a full bridge rectifier DB in the driving module 206.

In the leakage detection protection device 700, one end of the second signal line 25B is connected to one end of the resistor R3, and the other end is connected to the second end C of the first leakage detection line 241; the anode of the diode D1 is connected to the cathode of the diode D2 and to the first end a of the second leakage detection line 242; the cathode of the diode D1 is connected to the anode of the diode D2 and to the first end B of the first leakage detection line 241; one end of the first signal line 25A is connected to one ends of the resistors R5 and R2, and the other end is connected to the second end D of the second leakage detection line 242.

Under the normal operation condition of the leakage detection protection device 700, current flows through the first current carrying line 21-DB-R5-the first signal line 25A-the second leakage detection line 242-D1-the first leakage detection line 241-the second signal line 25B-R6-DB-SOL-the second current carrying line 22, the voltage at the point a is limited to a lower potential, such as lower than the threshold voltage of the zener diode ZD1, by setting the resistance values of the resistors R5 and R6, so that the voltage of the control electrode of the SCR is limited to an extremely low level, the SCR is not triggered, the switch module 203 is in a closed state, and the device 700 operates normally.

When the first current carrying line 21 has a leakage fault (i.e. a leakage current signal exists), the first leakage detection line 241 is electrified, so that the potential at point a is increased, and when the leakage current on the first current carrying line 21 exceeds a set threshold value, current (i.e. the leakage fault signal) flows through the first current carrying line 21, the first leakage detection line 241-D2, the second leakage detection line 242, and the first signal line 25A-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, a trip circuit of the second current carrying LINE 22-SOL-DB-SCR-DB-first current carrying LINE 21 is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently large to trip the reset switch RSET, thereby cutting off the power connection between the input terminal LINE and the output terminal LOAD.

When any one or more of the first leakage detection line 241, the second leakage detection line 242, the first signal line 25A, and the second signal line 25B is opened or closed, the potential at point a increases, and a current (i.e., an open fault signal) flows through the first current carrying line 21-DB-R5-R2-ZD1 to trigger the SCR to conduct. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

The leakage detection protection device 700 also has a test function. The fault test of the leakage detection module 204 may be performed by the test module 207. When the TEST switch TEST is closed, i.e. the TEST circuit is a closed loop, a current flows in the loop of the first current carrying line 21-TEST-R3-second signal line 25B-first leakage detection line 241-D2-second leakage detection line 242-first signal line 25A-R2-ZD 1-R4-DB-SOL-second current carrying line 22, i.e. the simulated leakage fault signal. The current will cause the voltage across resistor R4 to rise, triggering the SCR to turn on. When the SCR is turned on, the trip circuit is formed, a large current is generated on the solenoid SOL, and a magnetic field is formed sufficiently, so that the reset switch RSET trips, and the power connection between the input terminal LINE and the output terminal LOAD is cut off.

Fig. 8 shows a cross-sectional view of one embodiment of a power cord of the earth leakage detection protection device in accordance with the present utility model. As shown in fig. 8, the power supply line includes a first current carrying line (e.g., live line L) 21, a second current carrying line (e.g., neutral line N) 22, a third current carrying line (e.g., ground line G) 23, first and second leakage detection lines 241 and 242, and an insulating coating 27.

In the embodiment of fig. 8, the power line 2 has a circular shape, and the first current carrying line 21, the second current carrying line 22 and the third current carrying line 23 are respectively covered with an insulating layer, such as insulating layers 21A and 22A. It will be appreciated that the power cord 2 may also be a side-by-side flat cord or may have other finished profiles. As shown in fig. 8, the power cord 2 may also include a cord filler (or filler) 26. The first leakage detection line 241 covers the insulating layer 21A of the first current line 21, and the second leakage detection line 242 covers the insulating layer 22A of the second current line 21. The insulating structure 28 wraps the first leakage detection line 241. The insulating structure 28 may be integrally formed of a plastic material, or may be formed by coating a material conforming to the electrical insulating property, such as insulating paper or insulating cotton. In some embodiments, the outer sides of the first and second leakage detection lines 241 and 242 may be respectively covered with an insulating structure, or the outer sides of the second leakage detection lines 242 are covered with an insulating structure, and the outer sides of the first leakage detection lines 241 are not covered with an insulating structure. The first leakage detecting line 241 and the second leakage detecting line 242 may be a metal (e.g., copper, aluminum, etc.) braid structure, a wound structure composed of at least one metal wire, a metal foil clad structure, or a combination of any of these structures. In some embodiments, the first and second leakage detection lines 241 and 242 may be made of a single-sided insulating material (i.e., one side is an electrically conductive material and the other side is an insulating material), which is used as electrical insulation without requiring a separate insulating structure.

Fig. 9 shows a cross-sectional view of another embodiment of the power cord of the earth leakage detection protection device according to the present utility model. As shown in fig. 9, the power supply line 2 includes a first current carrying line (e.g., a live line L) 21, a second current carrying line (e.g., a neutral line N) 22, a third current carrying line (e.g., a ground line G) 23, a first leakage detection line 241, a second leakage detection line 242, a first signal line 25A, a second signal line 25B, and an insulating cover 27. In fig. 9, the first signal line 25A and the second signal line 25B are located on the same side of the third carrier line 23. It is to be understood that the first signal line 25A and the second signal line 25B may be arranged at any suitable position, not limited to the position shown in fig. 9.

In the embodiment of fig. 9, the power line 2 has a circular shape, and the first current carrying line 21, the second current carrying line 22 and the third current carrying line 23 are respectively covered with an insulating layer, such as insulating layers 21A and 22A. It will be appreciated that the power cord 2 may also be a side-by-side flat cord or may have other finished profiles. As shown in fig. 9, the power cord 2 may also include a cord filler (or filler) 26. The first leakage detection line 241 covers the insulating layer 21A of the first current line 21, and the second leakage detection line 242 covers the insulating layer 22A of the second current line 21. The first and second leakage detection lines 241 and 242 may be made of a single-sided insulating material (i.e., one side is an electrically conductive material and the other side is an insulating material), and the single-sided insulating material may be used as electrical insulation without a separate insulating structure. In some embodiments, the outer sides of the first and second leakage detection lines 241 and 242 are respectively covered with an insulating structure. In some embodiments, one of the first and second leakage detection lines 241 and 242 is clad with an insulating structure, while the other is not clad with an insulating structure. The insulating structure 28 may be integrally formed of a plastic material, or may be formed by coating a material conforming to the electrical insulating property, such as insulating paper or insulating cotton. The first leakage detecting line 241 and the second leakage detecting line 242 may be a metal (e.g., copper, aluminum, etc.) braid structure, a wound structure composed of at least one metal wire, a metal foil clad structure, or a combination of any of these structures.

In the above-described embodiment, the reliability of the leakage detection protection device is ensured by detecting whether or not the leakage detection line malfunctions. In addition, the leakage detection protection device provided by the utility model has the advantages of simple circuit structure, low cost and high safety.

A second aspect of the present utility model proposes an electrical connection device comprising: a housing; and a leakage detection protection device according to any one of the above embodiments, the leakage detection protection device being housed in the housing.

A third aspect of the present utility model proposes an electrical appliance comprising: a load device; and an electrical connection device coupled between the power supply line and the load device for supplying power to the load device, the electrical connection device including the leakage detection protection device of any of the above embodiments.

Therefore, while the present utility model has been described with reference to specific examples, which are intended to be illustrative only and not to be limiting of the utility model, it will be apparent to those of ordinary skill in the art that changes, additions or deletions may be made to the disclosed embodiments without departing from the spirit and scope of the utility model.

Claims

1. An earth leakage detection protection device, characterized in that the earth leakage detection protection device comprises:

a leakage detection module comprising a first leakage detection line, a second leakage detection line, and at least one resistive element and/or at least one semiconductor element, and configured to detect leakage current signals on the first and second current carrying lines, and to generate a leakage fault signal upon detection of the leakage current signals, wherein,

2. The leakage detection protection device of claim 1, wherein the first and second leakage detection lines each have a first end proximate to an input end of the first and second current carrying lines and a second end proximate to an output end of the first and second current carrying lines, and wherein the second end of the first leakage detection line is connected to the second end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

3. The leakage detection protection device of claim 1, wherein the first and second leakage detection lines each have a first end proximate to an input end of the first and second current carrying lines and a second end proximate to an output end of the first and second current carrying lines, and wherein the first end of the first leakage detection line is connected to the second end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

4. The leakage detection protection device of claim 1, wherein the first and second leakage detection lines each have a first end proximate to an input end of the first and second current carrying lines and a second end proximate to an output end of the first and second current carrying lines, and wherein the second end of the first leakage detection line is connected to the first end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

5. The leakage detection protection device of claim 1, wherein the first and second leakage detection lines each have a first end proximate to an input of the first and second current carrying lines and a second end proximate to an output of the first and second current carrying lines, and wherein the first end of the first leakage detection line is connected to the first end of the second leakage detection line through the at least one resistive element and/or the at least one semiconductor element.

6. The leakage detection protection device of any one of claims 1-5, wherein the at least one resistive element comprises a resistor, a capacitor, an inductor, and/or a wire.

7. The leakage detection and protection device according to any one of claims 1-5, wherein the at least one semiconductor element comprises a diode, a bipolar transistor, a field effect transistor, and/or a thyristor.

8. The electrical leakage detection protection device of claim 1, further comprising:

a detection monitoring module coupled to the leakage detection module and configured to detect whether an open circuit fault has occurred in the first and second leakage detection lines via the current loop and to generate an open circuit fault signal when the open circuit fault has occurred.

9. The leakage detection protection device of claim 8, wherein the detection monitoring module comprises at least one resistor and/or at least one diode.

10. The electrical leakage detection protection device of claim 8, further comprising:

a switching module configured to control an electrical connection between an input and an output of the first and second current carrying lines; and

A drive module coupled to the leakage detection module and/or the detection monitoring module and configured to drive the switch module to disconnect the power connection in response to the leakage fault signal and/or the open circuit fault signal.

11. The leakage detection protection device of claim 1, wherein at least one of the first leakage detection line and the second leakage detection line is externally coated with an insulating structure.

12. The leakage detection and protection device according to claim 11, wherein the insulating structure is formed integrally of plastic or is composed of insulating paper and/or insulating cotton.

13. The leakage detection protection device according to claim 1, wherein one side of the first leakage detection line and/or the second leakage detection line is an insulating material, and the other side is a conductive material.

14. The electrical leakage detection protection device of claim 1, further comprising:

a test module coupled to the leakage detection module and including a test switch and configured to generate the simulated leakage fault signal via the current loop to detect whether the leakage detection protection device is operating properly when the test switch is operated.

15. An electrical connection apparatus, the electrical connection apparatus comprising:

a housing; and

the leakage detection protection device according to any one of claims 1-14, the leakage detection protection device being housed in the housing.

16. An electrical appliance, the electrical appliance comprising:

a load device;

an electrical connection device coupled between a power supply line and the load device for supplying power to the load device, wherein the electrical connection device comprises the leakage detection protection apparatus according to any one of claims 1-14.