CN210156912U - Leakage protector - Google Patents

Abstract

The utility model discloses an earth leakage protection device, it includes switch module, electric leakage detection module, self-checking module, dropout module and safety switch module. The switch module is coupled between the input end and the output end and controls the power connection between the input end and the output end; the leakage detection module is coupled to the switch module and detects whether a leakage current signal exists at the output end; the self-checking module is coupled to the leakage detection module and the switch module and generates a self-checking pulse signal simulating a leakage current signal to detect whether the leakage detection module has a fault; the tripping module is coupled to the leakage current detection module, the self-detection module and the switch module and controls the switch module to cut off the power connection according to the detected leakage current signal and/or fault; the safety switch module is coupled to the input and the trip module, and is controlled by the trip module to break the power connection in the event of detection of a leakage current signal and/or a fault. The utility model has the advantages of high safety, simple structure, low cost, etc.

Description

Leakage protector

Technical Field

The utility model relates to a domestic circuit field especially relates to an earth leakage protection device.

Background

With the increasing popularization of household appliances, the power utilization safety awareness of people is continuously improved, and the leakage protection device is more and more widely used, but the leakage protection device used at present still has some defects. For example, when the earth leakage protection device is normally operated when the power is turned on, if a dangerous earth leakage fault exists at the load end, the time for the earth leakage protection device to actually turn off the power is prolonged because the power needs to charge various energy storage elements in the earth leakage detection module and the self-detection module when the power is turned on, and if the current leakage is too large, an electricity accident or personal safety or property loss may be caused.

For another example, when a thyristor in the leakage protection device connected to the input end of the product to which the working power supply is connected is short-circuited, a trip coil in the leakage protection device is continuously conducted, which may cause the product to be burned out, and a fire accident is caused in a serious case, thereby having potential safety hazards.

Therefore, there is a need for an earth leakage protection device with safety protection function, which is easy to install and has obvious economic benefit.

SUMMERY OF THE UTILITY MODEL

In view of the above problems, the present disclosure provides an earth leakage protection device, so as to improve the safety of the product.

The utility model provides an earth leakage protection device, it includes: the safety switch comprises a switch module, a leakage detection module, a self-checking module, a tripping module and a safety switch module. The switch module is coupled between the input end and the output end and controls the power connection between the input end and the output end; the leakage detection module is coupled to the switch module and detects whether a leakage current signal exists at the output end; the self-checking module is coupled to the leakage detection module and the switch module and periodically generates a self-checking pulse signal simulating a leakage current signal to detect whether the leakage detection module has a fault; the tripping module is coupled to the leakage current detection module, the self-detection module and the switch module and controls the switch module to cut off the power connection according to the detected leakage current signal and/or fault; and the safety switch module is coupled to the input end and the tripping module, and the tripping module is controlled to cut off the power connection under the condition of detecting a leakage current signal and/or a fault; in a first scenario, the safety switch module switches on the power connection before the switch module, and in a second scenario, the safety switch module switches off the power connection after the switch module.

In one embodiment, the distance between a pair of switch contacts in the safety switch module is different from the distance between a pair of switch contacts in the switch module, such that in the first scenario the safety switch module switches on a power connection before the switch module, and in the second scenario the safety switch module switches off a power connection after the switch module; the first scenario refers to the earth leakage protection device being switched from a power-off state to a power-on state; and the second scenario refers to the earth leakage protection device transitioning from the on state to the off state.

In one embodiment, the safety switch module is further coupled to the electrical leakage detection module and the self-test module, and in the first scenario, the safety switch module switches on a power connection to charge the first energy storage element in the electrical leakage detection module and the second energy storage element in the self-test module before the switch module switches on the power connection while providing the operating power to the trip module.

In one embodiment, when the switch module is connected to the power supply, the leakage detecting module starts to detect whether a leakage current signal exists at the output end, and the self-checking module starts to periodically generate the self-checking pulse signal to detect whether the leakage detecting module fails.

In one embodiment, when a component in the self-test module or a component in the trip module fails to form a loop between a trip coil in the trip module and the input terminal, the trip coil controls the switch module and the safety switch module to sequentially disconnect the power connection.

In one embodiment, the safety switch module is further coupled to the leakage detection module, and in the first scenario, the safety switch module makes a power connection to charge a first energy storage element in the leakage detection module before the switch module.

In one embodiment, the leakage detection module starts to detect whether the leakage current signal is present at the output terminal when the switch module switches on the power connection.

In one embodiment, the safety switch module is further coupled to the self-test module, and in the first scenario, the safety switch module makes a power connection to charge a second energy storage element in the self-test module before the switch module.

In one embodiment, the self-test module starts to periodically generate the self-test pulse signal to detect whether the leakage detecting module is malfunctioning when the switching module turns on the power connection.

In one embodiment, in the case where the safety switch module is coupled only to the input and the trip module, in the first scenario, the safety switch module makes a power connection prior to the switch module to provide operating power to the trip module.

In one embodiment, when a component in the self-test module or a component in the trip module fails to form a loop between a trip coil in the trip module and the input terminal, the trip coil controls the switch module and the safety switch module to sequentially disconnect the power connection.

Compared with the prior art, in order to increase earth leakage protection device's safety protection performance, the utility model discloses the safety switch module has been increased in earth leakage protection device for whether the disclosed earth leakage protection device not only can be in its work periodically automated inspection earth leakage protection function break down, whether there is leakage current in the detection, can also begin to carry out the self-detection when providing working power supply to earth leakage protection device, leakage detection, avoided realizing that earth leakage protection leads to serious consequence because the time delay that its self energy storage component's constitution characteristics caused, the product property ability that has greatly improved earth leakage protection device. And simultaneously, the utility model has the advantages of the security is high, simple structure, with low costs.

Drawings

Embodiments are shown and described with reference to the drawings. These drawings are provided to illustrate the basic principles and thus only show the aspects necessary for understanding the basic principles. The figures are not to scale. In the drawings, like reference numerals designate similar features.

Fig. 1 shows a schematic circuit configuration of a first embodiment of an earth leakage protection device according to the present disclosure;

fig. 2 shows a schematic circuit diagram of a second embodiment of an earth leakage protection device according to the present disclosure;

fig. 3 shows a schematic circuit diagram of a third embodiment of the earth leakage protection device according to the present disclosure; and

fig. 4 shows a schematic circuit diagram of a fourth embodiment of the earth leakage protection device according to the present disclosure.

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 invention may be practiced. The exemplary embodiments are not intended to be exhaustive of all embodiments according to the invention. 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 invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Embodiments of the present disclosure are primarily concerned with the following technical issues: because various energy storage elements exist in the existing earth leakage protection device, when the power supply is switched on, the earth leakage protection device usually needs to be charged and then can normally work, so if dangerous earth leakage faults exist when the earth leakage protection device is switched on, the time for the earth leakage protection device to switch off the power supply can be prolonged. In addition, when some elements in the existing leakage protection device are short-circuited, a trip coil in the leakage protection device is continuously conducted, so that the leakage protection device is possibly burnt, and potential safety hazards exist.

In order to solve the problem, the utility model discloses an earth leakage protection device, it includes switch module, the electric leakage detection module, the dropout module, self-checking module and safety switch module, wherein, safety switch module can be according to practical application needs respectively with the electric leakage detection module, the dropout module, one or more among the self-checking module are coupled, can in time detect the trouble of electric leakage trouble or earth leakage protection device itself when realizing that earth leakage protection device normally works, can also avoid simultaneously because certain part short circuit among the earth leakage protection device arouses the danger that whole device is burnt out.

Example 1

Fig. 1 shows a schematic circuit structure diagram of an earth leakage protection device according to a first embodiment of the present invention. As shown in fig. 1, the earth leakage protection device in the first embodiment includes: input LINE and output LOAD, be used for controlling the switch module 1, electric leakage detection module 2, dropout module 3, self-checking module 4 and the safety switch module 5 that are connected of electric power between input LINE and the output LOAD. The leakage detection module 2 is configured to detect whether there is a leakage signal at the input terminal LINE and the output terminal LOAD, and specifically detect whether there is a leakage signal at the phase LINE (L) and the neutral LINE (N) of the output terminal LOAD. The self-checking module 4 is used for detecting whether the electric leakage detection module 2 works normally. When the leakage current detection module 2 detects a leakage current signal, the control tripping module 3 drives the switch module 1 to disconnect the power supply, so that the circuit is protected. When the self-checking module 4 detects that the electric leakage detection module 2 breaks down, the control tripping module 3 drives the switch module 1 to disconnect the electric power connection, so that the power supply is cut off, and the circuit is protected.

As shown in fig. 1, the leakage detecting module 2 includes a leakage detecting loop ZCT1 passing through the phase line (L) and the neutral line (N), and a leakage detecting unit (which includes a leakage detecting chip U1 and its associated coupled electronic components (e.g., a capacitor C7, etc.)) coupled to the leakage detecting loop ZCT 1. When current imbalance exists between the phase line (L) and the neutral line (N) passing through the leakage detection loop ZCT1, that is, a leakage current signal exists, a corresponding voltage signal is generated on the leakage detection loop ZCT1, and the leakage detection chip U1 controls the trip module 3 to drive the switch module 1 to open by detecting a corresponding voltage change generated on the leakage detection loop ZCT 1.

In the present embodiment, the self-checking module 4 is used to perform periodic function check on the electrical leakage detecting module 2. The self-checking module 4 comprises a power circuit, a period timing circuit and a self-checking pulse signal circuit for simulating a leakage current signal. Referring to fig. 1, the power circuit includes a resistor R5, a voltage regulator ZD1, and a capacitor C3; the cycle timing circuit comprises a resistor R9 and a timing element (such as a capacitor C4) connected in series for generating intervals of self-test pulse signals; the self-test pulse signal circuit comprises a switching tube (silicon controlled transistor Q2), a comparator U2, a diode D2, a capacitor C5, a resistor R10, and electronic elements such as resistors R11 and R13 which are respectively coupled to an emitter, a base and a collector of a triode Q2. After the leakage detecting device is operated, the self-test module 4 periodically applies an analog leakage current signal to the leakage detecting loop ZCT1, the analog leakage current signal reaching a predetermined constant value.

In this embodiment, the trip module 3 includes a trip driving unit, and the trip driving unit includes semiconductor devices (thyristors Q1 and Q4) coupled to the leakage current detecting module 2 and the self-test module 4, and a trip coil SOL coupled to the thyristors (Q1 and Q4). When the leakage detecting chip U1 detects that the voltage variation generated on the leakage detecting ring ZCT1 reaches a predetermined value, the thyristors Q1 and Q4 can be turned on. When Q1 and Q4 are turned on, the trip coil SOL generates a large current change, and the switch module 1 and the safety switch module 5 are sequentially turned off.

When the self-checking module 4 detects that the leakage detecting module 2 has a fault, that is, the leakage detecting chip U1 cannot turn on the thyristor Q1, the capacitor C4 has no discharging circuit, so that the self-checking module 4 (pin 4 of the comparator U2) will continuously output a high level, the capacitor C5 is charged through the resistor R10, when the potential reaches a set value, the diode D2 is turned on, the thyristor Q1 and/or the thyristor Q4 are turned on, so that the trip coil SOL acts, and the switch module 1 and the safety switch module 5 are controlled to sequentially turn off the power connection.

That is to say, in this embodiment, the self-checking module 4 is used to automatically detect whether the leakage protection function is normal periodically in the working state of the leakage detection device, and when the leakage detection module 2 fails, the control tripping module 3 is used to drive the switch module 1 and the safety switch module 5 to sequentially cut off the output power supply. And/or when the leakage current detection module 2 detects that a leakage current signal exists, the switch module 1 and the safety switch module 5 are driven to be sequentially disconnected for output power supply through the control tripping module 3.

In addition, according to the first embodiment shown in fig. 1, the safety switch module 5 in this embodiment is coupled to the input terminal LINE and is also coupled to the leakage detecting module 2, the self-test module 4, and the trip module 3. In the present embodiment, in a first scenario (i.e., the earth leakage protection device is switched from the power-off state to the power-on state), the safety switch module 5 makes the power connection before the switch module 1, and in a second scenario (i.e., the earth leakage protection device is switched from the power-on state to the power-off state), the safety switch module 5 makes the power connection after the switch module 1.

Specifically, in the first scenario, the safety switch module 5 is connected to the power connection before the switch module 1 is connected to charge the first energy storage element (e.g., capacitor C7, etc.) in the leakage detection module 2 and the second energy storage element (e.g., capacitor C3, etc.) in the self-test module 4, and simultaneously provides the trip module 3 with a working power supply, so that the leakage detection module 2 and the self-test module 4 can work normally when the switch module 1 is connected to the power connection.

That is, when the switch module 1 is connected to the power supply, the leakage detecting module 2 starts to detect whether there is a leakage current signal at the output terminal, and the self-test module 4 starts to periodically generate a self-test pulse signal to detect whether the leakage detecting module 2 fails. And under the condition that a leakage current signal and/or the fault is detected, the leakage current detection module 2 and/or the self-checking module 4 sends a related fault signal to the trip module 3, so that the trip module 3 firstly controls the switch module 1 to cut off the power connection and then controls the safety switch module 5 to cut off the power connection.

In addition, when a component (e.g., a thyristor Q2) in the self-test module 4 or a component (e.g., a thyristor Q1) in the trip module 3 fails (e.g., short-circuits) to form a loop between the trip coil SOL in the trip module 3 and the input terminal, the trip coil SOL controls the switch module 1 and the safety switch module 5 to be sequentially disconnected from the power connection, so as to avoid the danger that the trip coil SOL is electrified for a long time without the safety switch module 5 to cause the possibility of burning the earth leakage protection device and other live equipment connected with the earth leakage protection device.

The leakage protection device disclosed in this embodiment, on one hand, can realize that the leakage detection module and the self-checking module immediately start normal operation when being turned on, so as to detect the leakage fault existing when being turned on, and avoid the problem caused by the delay processing of the leakage fault existing at the output end (i.e., the load end) when being turned on; on the other hand, the danger that the leakage protection device and other electrified equipment connected with the leakage protection device are burnt or accidents are caused due to the failure of the components in the self-checking module or the components in the tripping module can be avoided.

Example 2

The switch module 1, the leakage detection module 2, the trip module 3, and the self-checking module 4 in fig. 2 have the same structure as that in fig. 1, and are not described herein again. Compared to fig. 1, the position of the safety switch module 5 in fig. 2 in the earth leakage protection device has changed: as shown in fig. 2, the safety switch module 5 is coupled to the input and to the leakage detection module 2 and the trip module 3. In a first scenario, the safety switch module 5 switches on the power connection before the switch module 1 to charge the first energy storage element (e.g., the capacitor C7) in the leakage detection module 2, so that the leakage detection module 2 can operate normally when the switch module 1 switches on the power connection.

When the switch module 1 is connected to the power supply, the leakage detecting module 2 starts to detect whether a leakage signal exists at the output terminal. Under the condition that a leakage current signal exists, the leakage detection module 2 sends a leakage signal to the tripping module 3, so that the tripping module 3 controls the switch module 1 and the safety switch module 5 to be sequentially switched off.

The leakage protection device disclosed in embodiment 2 can realize that the leakage detection module starts to operate normally when the device is turned on, so that the leakage fault existing at the load end when the device is turned on can be detected, and the problem of delay processing of the leakage fault existing when the device is turned on is solved.

Example 3

The switch module 1, the leakage detection module 2, the trip module 3, and the self-checking module 4 in fig. 3 have the same structure as that in fig. 1, and are not described herein again. Compared to fig. 1 and 2, the position of the safety switch module 5 in fig. 3 in the earth leakage protection device changes: as shown in fig. 3, the safety switch module 5 is coupled to the input and to the self-test module 4 and the trip module 3. In a first scenario, the safety switch module 5 makes the power connection before the switch module 1 to charge the second energy storage element (e.g., capacitor C3) in the self-test module 4, so that the self-test module 4 can operate normally when the switch module 1 makes the power connection.

When the switch module 1 is connected to power, the self-test module 4 starts to periodically generate a self-test pulse signal to detect whether the leakage detecting module 2 malfunctions. When a fault exists, the self-checking module 4 sends a module fault signal to the tripping module 3, so that the tripping module 3 controls the switch module 1 and the safety switch module 5 to be sequentially switched off.

The leakage protection device disclosed in embodiment 3 can realize that the self-checking module starts to operate normally when the leakage protection device is turned on, so that the power-on self-checking of the leakage protection device can be performed immediately, and the problem of delayed processing of module faults existing at a load end when the leakage protection device is turned on is solved.

Example 4

The switch module 1, the leakage detection module 2, the trip module 3, and the self-checking module 4 in fig. 4 have the same structure as that in fig. 1, and are not described herein again. Compared to fig. 1 to 3, the position of the safety switch module 5 in fig. 4 in the earth leakage protection device has changed: as shown in fig. 4, the safety switch module 5 is coupled only to the input and trip module 3. In the present embodiment, when the earth leakage protection device is operating normally, the safety switch module 5 switches on the power connection before the switch module 1 to provide the operating power to the trip module 3.

In a first scenario, when a component (e.g., a thyristor Q2) in the self-test module 3 or a component (e.g., a thyristor Q1) in the trip module 3 fails, so that the trip coil SOL in the trip module forms a loop with the phase line (L) and the neutral line (N) of the input end, the trip coil SOL can control the switch module 1 and the safety switch module 5 to sequentially disconnect the power.

In the above-described embodiments 1 to 4, it is possible to realize that the safety switch module 5 turns on the power connection before the switch module 1 in the first scene and the switch module 1 turns off the power connection before the safety switch module 5 in the second scene by setting the distance between the pair of switch contacts in the safety switch module 5 and the distance between the pair of switch contacts in the switch module 1 to be different. The utility model discloses a this kind of design can ensure after load circuit disconnection, electric leakage detection module 2 and/or self-checking module 4 just stop work to improve earth leakage protection device's security.

The leakage protection device disclosed in embodiment 4 can avoid the danger that the leakage protection device and even other live equipment connected with the leakage protection device are burned or accidents are caused due to the failure of the components in the self-test module or the components in the trip module.

The utility model discloses an earth leakage protection device can enough guarantee that earth leakage protection device goes up the electric work time can begin the self-checking and/or carry out earth leakage detection to ensure that earth leakage protection device in time cuts off working power supply when going up the electric work and breaking down, can avoid again because this earth leakage protection device that part trouble among the earth leakage protection device arouses is burnt out or causes the danger of accident rather than other live equipment connected even, therefore improved the security performance. In addition, the disclosed leakage protection device has simple structure and low manufacturing cost, and can be widely applied to various fields needing leakage protection.

Therefore, while the present invention has been described with reference to specific examples, which are intended to be illustrative only and not to be limiting of the invention, 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 invention.

Claims (11)

1. An earth leakage protection device, comprising:

a switch module coupled between an input and an output and for controlling a power connection between the input and the output;

a leakage detection module coupled to the switch module and configured to detect whether a leakage signal exists at the output terminal;

a self-test module coupled to the leakage current detection module and the switch module, and configured to periodically generate a self-test pulse signal simulating the leakage current signal to detect whether the leakage current detection module fails;

a trip module, coupled to the leakage current detection module, the self-test module and the switch module, for controlling the switch module to disconnect power connection according to the detected leakage current signal and/or the fault; and

a safety switch module coupled to the input and the trip module and controlled by the trip module to break a power connection if the leakage current signal and/or the fault is detected; in a first scenario, the safety switch module switches on the power connection before the switch module, and in a second scenario, the safety switch module switches off the power connection after the switch module.

2. A residual current protection device according to claim 1,

a distance between a pair of switch contacts in the safety switch module is different from a distance between a pair of switch contacts in the switch module such that the safety switch module makes a power connection before the switch module in the first scenario and breaks a power connection after the switch module in the second scenario;

the first scenario refers to the earth leakage protection device being switched from a power-off state to a power-on state; and is

The second scenario refers to the earth leakage protection device transitioning from the on state to the off state.

3. The earth leakage protection device of claim 2, wherein the safety switch module is further coupled to the electrical leakage detection module and the self-test module, and in the first scenario, the safety switch module switches on a power connection prior to the switch module to charge a first energy storage element in the electrical leakage detection module and a second energy storage element in the self-test module while providing operating power to the trip module.

4. The device as claimed in claim 3, wherein when the switch module is connected to the power supply, the leakage detecting module starts to detect whether a leakage current signal exists at the output terminal, and the self-checking module starts to periodically generate the self-checking pulse signal to detect whether the leakage detecting module fails.

5. The earth leakage protection device of claim 3, wherein in a case where the switch module is electrically connected, when a component in the self-test module or a component in the trip module fails to form a loop between a trip coil in the trip module and the input terminal, the trip coil controls the switch module and the safety switch module to sequentially disconnect the electrical connection.

6. The earth leakage protection device of claim 2, wherein the safety switch module is further coupled to the earth leakage detection module, and in the first scenario, the safety switch module makes a power connection to charge a first energy storage element in the earth leakage detection module before the switch module.

7. The earth leakage protection device of claim 6, wherein said leakage detection module starts to detect whether said leakage current signal is present at said output terminal when said switch module is connected to power.

8. A residual current device according to claim 2, characterized in that said safety switch module is further coupled to said self-test module, said safety switch module, in said first scenario, switching on a power connection to charge a second energy storage element in said self-test module before said switch module.

9. The earth leakage protection device according to claim 8, wherein said self-checking module starts to periodically generate said self-checking pulse signal to detect whether said earth leakage detection module is malfunctioning when said switch module is connected to power.

10. The residual current device according to claim 2, wherein in a case where said safety switch module is coupled only to said input and said trip module, in said first scenario, said safety switch module makes a power connection prior to said switch module to provide operating power to said trip module.

11. The earth leakage protection device of claim 10, wherein in a case where the switch module is electrically connected, when a component in the self-test module or a component in the trip module fails to form a loop between a trip coil in the trip module and the input terminal, the trip coil controls the switch module and the safety switch module to sequentially disconnect the electrical connection.

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