Earth leakage protection device, electric connection equipment and electric appliance

Abstract

The invention provides an earth leakage protection device, which comprises a switch module for controlling the power connection between an input end and an output end; the electric leakage detection module is used for detecting a leakage current signal on the current-carrying line and generating an electric leakage fault signal when the leakage current signal is detected or the leakage current signal exceeds a preset threshold value; the over-temperature protection module comprises a first temperature sensor and a second temperature sensor, the first temperature sensor is close to the first plug piece and detects the temperature near the first plug piece, and the second temperature sensor is close to the second plug piece and detects the temperature near the second plug piece; the over-temperature protection module generates an over-temperature fault signal when the temperature detected by the first temperature sensor and / or the second temperature sensor exceeds a preset threshold value; and the driving module receives the electric leakage fault signal and drives the switch module to disconnect the power connection in response to the electric leakage fault signal. Power connection can be cut off in time when the temperature of the plug pieces is too high, dangers are avoided, and the over-temperature protection precision is high.

Description

Technical Field

[0001] The invention relates to the electrical field, and in particular to a leakage protection device, an electrical connection device and an electrical appliance. Background Art

[0002] In order to improve the safety of electricity use, leakage protection devices are being used more and more widely, and their application fields and scenarios are also continuing to increase. Existing leakage protection devices can provide basic leakage protection functions. When leakage is detected at the load end, the product can quickly cut off the power to the load end to protect the personal safety of the user. However, in actual use, there are often local overheating of the leakage protection device due to poor contact caused by reduced socket clamping force, line overload and other reasons. This causes the product shell to melt and even cause fires from time to time, which also brings major safety hazards and seriously endangers the safety of users' lives and property. Summary of the invention

[0003] Based on the above problem, the first aspect of the present invention proposes a leakage protection device, comprising: a switch module, which is coupled between an input end and an output end of a current-carrying line and is configured to control the power connection between the input end and the output end, wherein the input end of the current-carrying line is connected to a first plug blade and a second plug blade; a leakage detection module, which is configured to detect a leakage current signal on the current-carrying line and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, which comprises a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is arranged close to the first plug blade and is configured to detect a temperature near the first plug blade, and the second temperature sensor is arranged close to the second plug blade and is configured to detect a temperature near the second plug blade, wherein the over-temperature protection module is configured to generate an over-temperature fault signal when the temperature detected by the first temperature sensor and / or the second temperature sensor exceeds a preset threshold; and a driving module, which is coupled to the switch module and the leakage detection module and is configured to receive the leakage fault signal and drive the switch module to disconnect the power connection in response to the leakage fault signal.

[0004] In some embodiments, the over-temperature protection module also includes: a first voltage divider element, which is connected in series with the first temperature sensor; a second voltage divider element, which is connected in series with the second temperature sensor; and a first comparison unit, which is coupled to the first voltage divider element and the second voltage divider element, wherein, when the temperature detected by the first temperature sensor and / or the second temperature sensor exceeds the preset threshold, the first voltage divider element and / or the second voltage divider element provides an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate the over-temperature fault signal.

[0005] In some embodiments, the over-temperature protection module also includes: a first isolation element, coupled between the first temperature sensor and the first comparison unit; and a second isolation element, coupled between the second temperature sensor and the first comparison unit, wherein the first isolation element and the second isolation element are configured to isolate the temperature detection signals of the first temperature sensor and the second temperature sensor.

[0006] In some embodiments, the first isolation element and the second isolation element are diodes respectively.

[0007] In some embodiments, the leakage protection module includes a leakage detection chip, and the leakage detection chip is coupled to the first comparison unit to provide a reference voltage to the first comparison unit; or the over-temperature protection module also includes a third voltage divider element and a fourth voltage divider element connected in series, and the third voltage divider element and the fourth voltage divider element are coupled to the first comparison unit and are configured to provide a reference voltage to the first comparison unit.

[0008] In some embodiments, the over-temperature protection module also includes: a first voltage divider element, which is connected in series with the first temperature sensor; a second voltage divider element, which is connected in series with the second temperature sensor; a first comparison unit, which is coupled to the first voltage divider element; and a second comparison unit, which is coupled to the second voltage divider element, wherein, when the temperature detected by the first temperature sensor exceeds the preset threshold, the first voltage divider element provides an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate the over-temperature fault signal; and / or when the temperature detected by the second temperature sensor exceeds the preset threshold, the second voltage divider element provides the over-temperature detection signal to the second comparison unit, thereby causing the second comparison unit to generate the over-temperature fault signal.

[0009] In some embodiments, the driving module is further coupled to the over-temperature protection module, and is further configured to receive the over-temperature fault signal, and drive the switch module to disconnect the power connection in response to the over-temperature fault signal.

[0010] In some embodiments, the driving module also includes: at least one first semiconductor element, which is coupled to the leakage detection module and configured to receive the leakage fault signal and change the switch state in response to the leakage fault signal; and at least one second semiconductor element, which is coupled to the over-temperature protection module and configured to receive the over-temperature fault signal and change the switch state in response to the over-temperature fault signal.

[0011] In some embodiments, the driving module also includes: a reset switch, which can be operated to: drive the switch module to reconnect the power connection when the driving module drives the switch module to disconnect the power connection in response to the leakage fault signal, and maintain the disconnected state of the power connection when the driving module drives the switch module to disconnect the power connection in response to the over-temperature fault signal.

[0012] In some embodiments, the leakage protection device also includes: an over-temperature self-detection module, which is coupled to the over-temperature protection module and the driving module, and is configured to detect whether the over-temperature protection module fails, and generate an over-temperature self-detection fault signal when the over-temperature protection module fails, and the driving module is also configured to receive the over-temperature self-detection fault signal and drive the switch module to disconnect the power connection in response to the over-temperature self-detection fault signal.

[0013] In some embodiments, the over-temperature self-test module includes a third comparison unit, which is coupled to the first temperature sensor and the second temperature sensor and configured to be triggered to generate the over-temperature self-test fault signal when the first temperature sensor and the second temperature sensor fail.

[0014] In some embodiments, the over-temperature self-test module also includes: a first voltage stabilizing component, which is coupled to the first temperature sensor and the third comparison unit; a second voltage stabilizing component, which is coupled to the second temperature sensor and the third comparison unit, wherein the first voltage stabilizing component and the second voltage stabilizing component are configured to increase the trigger voltage of the third comparison unit.

[0015] In some embodiments, the over-temperature self-test module also includes: a third isolation element, coupled between the first temperature sensor and the third comparison unit; and a fourth isolation element, coupled between the second temperature sensor and the third comparison unit, wherein the third isolation element and the fourth isolation element are configured to isolate the temperature detection signals of the first temperature sensor and the second temperature sensor.

[0016] In some embodiments, the leakage protection device also includes: a leakage self-detection module, which is coupled to the leakage detection module and the driving module, and is configured to periodically generate a simulated leakage current signal to detect whether the leakage detection module and / or the driving module fails, and generate a leakage self-detection fault signal when the leakage detection module and / or the driving module fails, and the driving module is also configured to receive the leakage self-detection fault signal and drive the switch module to disconnect the power connection in response to the leakage self-detection fault signal.

[0017] The leakage protection device provided in the first aspect of the present invention includes an over-temperature protection module, and by arranging temperature sensors near two plug blades respectively, the temperature of the two plug blades can be accurately and independently detected, thereby improving the accuracy of over-temperature protection. When the temperature of the plug blade is too high, an over-temperature fault signal can be issued to avoid danger, eliminate potential safety hazards, and increase the safety of the leakage protection device.

[0018] A second aspect of the present invention provides a leakage protection device, comprising: a switch module, which is coupled between an input end and an output end of a current-carrying line and is configured to control the power connection between the input end and the output end; a leakage detection module, which is configured to detect a leakage current signal on the current-carrying line and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, which is configured to detect the temperature of a specific element and / or a specific position and generate an over-temperature fault signal when the temperature of the specific element and / or the specific position exceeds a preset threshold; and a drive module, which is coupled to the switch module, the drive module comprising: at least one first semiconductor element, which is coupled to the leakage detection module and is configured to receive the leakage fault signal and change the switch state in response to the leakage fault signal, thereby driving the switch module to disconnect the power connection; and at least one second semiconductor element, which is coupled to the over-temperature protection module and is configured to receive the over-temperature fault signal and change the switch state in response to the over-temperature fault signal, thereby driving the switch module to disconnect the power connection.

[0019] In some embodiments, the driving module also includes: a reset switch, which can be operated to: drive the switch module to reconnect the power connection when the at least one first semiconductor element drives the switch module to disconnect the power connection in response to the leakage fault signal, and maintain the disconnected state of the power connection when the at least one second semiconductor element drives the switch module to disconnect the power connection in response to the over-temperature fault signal.

[0020] In some embodiments, the leakage protection device also includes: an over-temperature self-detection module, which is coupled to the over-temperature protection module and the driving module, and is configured to detect whether the over-temperature protection module fails, and generate an over-temperature self-detection fault signal when the over-temperature protection module fails, and the at least one second semiconductor element is also configured to receive the over-temperature self-detection fault signal and change the switch state in response to the over-temperature self-detection fault signal, thereby driving the switch module to disconnect the power connection.

[0021] In some embodiments, the over-temperature protection module includes at least one temperature sensor, and the over-temperature self-test module includes a third comparison unit, which is coupled to the at least one temperature sensor and is configured to be triggered to generate the over-temperature self-test fault signal when the at least one temperature sensor fails.

[0022] In some embodiments, the over-temperature self-test module further includes at least one voltage stabilizing component coupled to the at least one temperature sensor and the third comparison unit, wherein the at least one voltage stabilizing component is configured to increase a trigger voltage of the third comparison unit.

[0023] The leakage protection device provided in the second aspect of the present invention realizes the independence of the two functions of leakage protection and over-temperature protection by respectively providing different semiconductor elements for the leakage detection module and the over-temperature protection module to drive the switch module, thereby further increasing the safety of the leakage protection device.

[0024] The third aspect of the present invention proposes a leakage protection device, comprising: a switch module, which is coupled between the input end and the output end of the current-carrying line and is configured to control the power connection between the input end and the output end; a leakage detection module, which is configured to detect the leakage current signal on the current-carrying line, and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, which is configured to detect the temperature of a specific component and / or a specific position, and generate an over-temperature fault signal when the temperature of the specific component and / or the specific position exceeds a preset threshold; an over-temperature self-detection module a block, which is coupled to the over-temperature protection module and is configured to detect whether the over-temperature protection module fails and generate an over-temperature self-test fault signal when the over-temperature protection module fails; and a driving module, which is coupled to the switch module, the leakage detection module, the over-temperature protection module and the over-temperature self-test module, and is configured to receive the leakage fault signal, the over-temperature fault signal and the over-temperature self-test fault signal, and drive the switch module to disconnect the power connection in response to one or more of the leakage fault signal, the over-temperature fault signal and the over-temperature self-test fault signal.

[0025] In some embodiments, the over-temperature protection module includes at least one temperature sensor, and the over-temperature self-test module includes a third comparison unit, which is coupled to the at least one temperature sensor and is configured to be triggered to generate the over-temperature self-test fault signal when the at least one temperature sensor fails.

[0026] In some embodiments, the over-temperature self-test module further includes at least one voltage stabilizing component coupled to the at least one temperature sensor and the third comparison unit, wherein the at least one voltage stabilizing component is configured to increase a trigger voltage of the third comparison unit.

[0027] The leakage protection device provided in the third aspect of the present invention performs self-check on the over-temperature protection function of the device by setting an over-temperature self-check module, and cuts off the power connection when the over-temperature protection function fails, thereby further increasing the safety of the leakage protection device.

[0028] A fourth aspect of the present invention provides an electrical connection device, comprising: a housing; and a leakage protection device according to any one of the embodiments of the first, second and third aspects, wherein the leakage protection device is accommodated in the housing.

[0029] A fifth aspect of the present invention provides an electrical appliance, comprising: a load device; and an electrical connection device according to any one of the embodiments of the fourth aspect, which is coupled to the load device and is used to supply power to the load device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The embodiments are shown and explained with reference to the accompanying drawings. These drawings are used to illustrate the basic principles, and only the aspects necessary for understanding the basic principles are shown. These drawings are not to scale. In the drawings, the same reference numerals represent similar features. In addition, the connection between each box in the architecture diagram indicates that the two boxes are electrically coupled, and the absence of a connection between the two boxes does not mean that the two boxes are not coupled.

[0031] Figure 1 A schematic structural diagram of a leakage protection device according to an embodiment of the present invention is shown;

[0032] Figure 2 A schematic structural diagram of a leakage protection device according to an embodiment of the present invention is shown;

[0033] Figure 3 A schematic structural diagram of a leakage protection device according to an embodiment of the present invention is shown;

[0034] Figure 4 A schematic principle diagram of a leakage protection device according to an embodiment of the present invention is shown;

[0035] Figure 5A A schematic diagram of an over-temperature protection module according to an embodiment of the present invention is shown;

[0036] Figure 5B A schematic diagram of an over-temperature protection module and a part of a driving module according to an embodiment of the present invention is shown;

[0037] Figure 5C A schematic diagram of an over-temperature protection module and a part of a driving module according to an embodiment of the present invention is shown;

[0038] Figure 5D A schematic diagram of an over-temperature protection module, an over-temperature self-detection module and a part of a driving module according to an embodiment of the present invention is shown;

[0039] Figure 5E A schematic diagram of an over-temperature protection module, an over-temperature self-detection module and a part of a driving module according to an embodiment of the present invention is shown;

[0040] Fig. 5F A schematic principle diagram of an over-temperature protection module and a part of a driving module according to an embodiment of the present invention is shown.

[0041] Figure 6 A schematic principle diagram of a leakage protection device according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0042] In the following specific description of the preferred embodiments, reference will be made to the attached drawings which constitute a part of the present invention. The attached drawings show by way of example specific embodiments that can implement the present invention. The illustrative embodiments are not intended to be exhaustive of all embodiments according to the present invention. It will be appreciated that other embodiments may be utilized, and structural or logical modifications may also be made without departing from the scope of the present invention. Therefore, the following specific description is not restrictive, and the scope of the present invention is limited by the appended claims.

[0043] Before introducing the embodiments of the present invention, some terms involved in the present invention are first explained to facilitate a better understanding of the present invention.

[0044] The terms "connection" or "coupling" and similar terms used in the present invention are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "A", "a group" or "an" and similar words do not indicate a quantity limitation, but indicate the presence of at least one.

[0045] The terms "include", "comprising" and similar terms used in the present invention should be understood as open terms, that is, "including / includes but not limited to", indicating that other contents may also be included. The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment" and so on. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0046] Figure 1 FIG. 2 shows a schematic structural diagram of a leakage protection device according to an embodiment of the present invention. Figure 1 As shown in FIG. 1 , the leakage protection device 100 includes a switch module 103, a leakage detection module 104, an over-temperature protection module 105, and a drive module 106. The switch module 103 is coupled between the input end 101 and the output end 102 of the current-carrying line, and controls the power connection between the input end 101 and the output end 102 of the current-carrying line. The input end 101 of the current-carrying line is connected to the first plug blade and the second plug blade. The current-carrying line may include a first current-carrying line (L) for connecting to the live wire of the power grid and a second current-carrying line (N) for connecting to the neutral wire of the power grid. When the first plug blade and the second plug blade are inserted into a power port (such as a socket), the current-carrying line is connected to the live wire and the neutral wire of the power grid. The leakage detection module 104 detects the leakage current signal on the current-carrying line, and generates a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold. The over-temperature protection module 105 includes a first temperature sensor 1051 and a second temperature sensor 1052. The first temperature sensor 1051 is arranged to be close to the first plug blade and detect the temperature near the first plug blade. The second temperature sensor 1052 is arranged close to the second plug blade and detects the temperature near the second plug blade. The first and second temperature sensors 1051 and 1052 can be thermistors, diodes and / or bimetal switches. The over-temperature protection module 105 generates an over-temperature fault signal when the temperature detected by the first temperature sensor 1051 and / or the second temperature sensor 1052 exceeds a preset threshold. The driving module 106 is coupled to the switch module 103 and the leakage detection module 104, receives the leakage fault signal, and drives the switch module 103 to disconnect the power connection in response to the leakage fault signal.

[0047] The leakage protection device 100 of this embodiment includes an over-temperature protection module 105, and by arranging temperature sensors near the two plug blades, the temperature of the two plug blades can be accurately and independently detected, thereby improving the accuracy of over-temperature protection. When the temperature of the plug blade is too high, an over-temperature fault signal can be issued to avoid danger, eliminate potential safety hazards, and increase the safety of the leakage protection device.

[0048] In some embodiments, the over-temperature protection module 105 further includes a first voltage divider element, a second voltage divider element and a first comparison unit. The first voltage divider element is connected in series with the first temperature sensor 1051, and the second voltage divider element is connected in series with the second temperature sensor 1052. The first comparison unit is coupled to the first voltage divider element and the second voltage divider element. The first and second voltage divider elements may be, for example, resistors, inductors or capacitors. The first comparison unit may be, for example, a trigger diode, a triode, a field effect transistor and / or a comparator. When the temperature detected by the first temperature sensor 1051 and / or the second temperature sensor 1052 exceeds a preset threshold value, the first voltage divider element and / or the second voltage divider element provide an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate an over-temperature fault signal.

[0049] In some embodiments, the over-temperature protection module 105 further includes a first isolation element and a second isolation element. The first isolation element is coupled between the first temperature sensor 1051 and the first comparison unit, and the second isolation unit is coupled between the second temperature sensor 1052 and the first comparison unit. The first isolation element and the second isolation element isolate the temperature detection signals of the first temperature sensor 1051 and the second temperature sensor 1052. The first and second isolation elements may be, for example, diodes. By providing an isolation element in the over-temperature protection module 105, the detection results of the two temperature sensors may not affect each other, the independence of temperature detection may be achieved, and the accuracy of over-temperature protection may be further improved.

[0050] In some embodiments, the leakage protection module 104 includes a leakage detection chip. The leakage detection chip is coupled to the first comparison unit to provide a reference voltage to the first comparison unit. Alternatively, the over-temperature protection module also includes a third voltage divider element and a fourth voltage divider element connected in series. The third voltage divider element and the fourth voltage divider element are coupled to the first comparison unit and provide a reference voltage to the first comparison unit.

[0051] In some embodiments, the over-temperature protection module 105 further includes a first voltage divider element, a second voltage divider element, a first comparison unit, and a second comparison unit. The first voltage divider element is connected in series with the first temperature sensor 1051, and the second voltage divider element is connected in series with the second temperature sensor 1052. The first and second comparison units may be, for example, a trigger diode, a triode, a field effect tube, and / or a comparator. The first comparison unit is coupled to the first voltage divider element, and the second comparison unit is coupled to the second voltage divider element. When the temperature detected by the first temperature sensor 1051 exceeds a preset threshold, the first voltage divider element provides an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate an over-temperature fault signal. When the temperature detected by the second temperature sensor 1052 exceeds a preset threshold, the second voltage divider element provides an over-temperature detection signal to the second comparison unit, thereby causing the second comparison unit to generate an over-temperature fault signal. By setting two comparison units for the two temperature sensors respectively, the detection results of the two temperature sensors can be made independent of each other, the independence of temperature detection is achieved, and the accuracy of over-temperature protection is further improved.

[0052] In some embodiments, the driving module 106 is also coupled to the over-temperature protection module 105, receives the over-temperature fault signal, and drives the switch module 103 to disconnect the power connection in response to the over-temperature fault signal. By coupling the driving module 106 with the over-temperature protection module 105, the driving module 106 can cut off the power connection in time when the temperature of the plug piece is too high, eliminating the safety hazard when the user is not paying attention or is not present, and further increasing the safety of the leakage protection device.

[0053] In some embodiments, the driving module 106 further includes at least one first semiconductor element and at least one second semiconductor element. At least one first semiconductor element is coupled to the leakage detection module 104, receives a leakage fault signal, and changes a switch state in response to the leakage fault signal. At least one second semiconductor element is coupled to the over-temperature protection module 105, receives an over-temperature fault signal, and changes a switch state in response to the over-temperature fault signal. By providing different semiconductor elements for the leakage detection module 104 and the over-temperature protection module 105 to drive the switch module 103, the independence of the two functions of leakage protection and over-temperature protection is achieved, and the safety of the leakage protection device is further increased.

[0054] In some embodiments, the driving module 106 also includes a reset switch, which can be operated to: drive the switch module 103 to reconnect the power connection when the driving module 106 drives the switch module 103 to disconnect the power connection in response to a leakage fault signal, and maintain the disconnected state of the power connection when the driving module 106 drives the switch module 103 to disconnect the power connection in response to an over-temperature fault signal.

[0055] In some embodiments, the leakage protection device 100 further includes an over-temperature self-check module, which is coupled to the over-temperature protection module 105 and the driving module 106, detects whether the over-temperature protection module 105 fails, and generates an over-temperature self-check fault signal when the over-temperature protection module 105 fails. The driving module 106 receives the over-temperature self-check fault signal, and drives the switch module 103 to disconnect the power connection in response to the over-temperature self-check fault signal. By providing the over-temperature self-check module, the power connection can be cut off in time when the over-temperature protection module 105 fails (such as the failure of the first temperature sensor 1051 and / or the second temperature sensor 1052), further increasing the safety of the leakage protection device.

[0056] In some embodiments, the over-temperature self-test module includes a third comparison unit, which is coupled to the first temperature sensor 1051 and the second temperature sensor 1052, and is triggered to generate an over-temperature self-test fault signal when a fault occurs in the first temperature sensor 1051 and the second temperature sensor 1052. The third comparison unit can be, for example, a trigger diode, a triode, a field effect tube and / or a comparator.

[0057] In some embodiments, the over-temperature self-test module further includes a first voltage stabilizing component and a second voltage stabilizing component. The first voltage stabilizing component is coupled to the first temperature sensor 1051 and the third comparison unit. The second voltage stabilizing component is coupled to the second temperature sensor 1052 and the third comparison unit. The first voltage stabilizing component and the second voltage stabilizing component are used to increase the trigger voltage of the third comparison unit. The first and second voltage stabilizing components can, for example, respectively include a combination of a resistor and a voltage stabilizing diode.

[0058] In some embodiments, the over-temperature self-test module further includes a third isolation element and a fourth isolation element. The third isolation element is coupled between the first temperature sensor 1051 and the third comparison unit, and the fourth isolation element is coupled between the second temperature sensor 1052 and the third comparison unit. The third isolation element and the fourth isolation element isolate the temperature detection signals of the first temperature sensor 1051 and the second temperature sensor 1052. The third and fourth isolation elements may be diodes, for example. By providing isolation elements in the over-temperature self-test module, the detection results of the two temperature sensors may not affect each other, thereby achieving independence of temperature detection.

[0059] In some embodiments, the leakage protection device 100 further includes a leakage self-check module, which is coupled to the leakage detection module 104 and the driving module 106. The leakage self-check module periodically generates a simulated leakage current signal to detect whether the leakage detection module 104 and / or the driving module 106 fails, and generates a self-check fault signal when the leakage detection module 104 and / or the driving module 106 fails. The driving module 106 receives the leakage self-check fault signal, and drives the switch module 103 to disconnect the power connection in response to the leakage self-check fault signal. By providing the leakage self-check module in the leakage protection device 100, the power connection can be cut off in time when the leakage detection module 104 and / or the driving module 106 fails, which further increases the safety of the leakage protection device.

[0060] Figure 2 FIG. 2 shows a schematic structural diagram of a leakage protection device according to an embodiment of the present invention. Figure 2 As shown in FIG. 1 , the leakage protection device 200 includes a switch module 203, a leakage detection module 204, an over-temperature protection module 205, and a drive module 206. The switch module 203 is coupled between the input end 201 and the output end 202 of the current-carrying line, and controls the power connection between the input end 201 and the output end 202 of the current-carrying line. The current-carrying line may include a first current-carrying line (L) for connecting to the live line of the power grid and a second current-carrying line (N) for connecting to the neutral line of the power grid. The leakage detection module 204 detects the leakage current signal on the current-carrying line, and generates a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold. The over-temperature protection module 205 may include, for example, at least one temperature sensor, which detects the temperature of a specific element and / or a specific position, and generates an over-temperature fault signal when the temperature of the specific element and / or a specific position exceeds a preset threshold. The drive module 206 is coupled to the switch module 203, and includes at least one first semiconductor element 2061 and at least one second semiconductor element 2061. At least one first semiconductor element 2061 is coupled to the leakage detection module 204, receives the leakage fault signal and changes the switch state in response to the leakage fault signal, thereby driving the switch module 203 to disconnect the power connection. At least one second semiconductor element 2062 is coupled to the over-temperature protection module 205, receives the over-temperature fault signal and changes the switch state in response to the over-temperature fault signal, thereby driving the switch module 203 to disconnect the power connection.

[0061] The leakage protection device 200 of this embodiment realizes the independence of the leakage protection and over-temperature protection functions by respectively providing different semiconductor elements for the leakage detection module 204 and the over-temperature protection module 205 to drive the switch module 203 , thereby further increasing the safety of the leakage protection device 200 .

[0062] In some embodiments, the driving module 206 further includes a reset switch, which can be operated to: drive the switch module 203 to connect the power connection again when at least one first semiconductor element 2061 drives the switch module 203 to disconnect the power connection in response to a leakage fault signal, and keep the power connection disconnected when at least one second semiconductor element 2062 drives the switch module 203 to disconnect the power connection in response to an over-temperature fault signal. In this way, in the event that the over-temperature protection disconnects the power connection, the user can be prevented from resetting the leakage protection device 200 by operating the reset switch, and the user needs to unplug the plug blade for inspection before using it again, which further increases the safety of the leakage protection device 200.

[0063] In some embodiments, the leakage protection device 200 further includes an over-temperature self-detection module, which is coupled to the over-temperature protection module 205 and the driving module 206. The over-temperature self-detection module detects whether the over-temperature protection module 205 fails, and generates an over-temperature self-detection fault signal when the over-temperature protection module 205 fails. At least one second semiconductor element 2062 also receives the over-temperature self-detection fault signal, and changes the switch state in response to the over-temperature self-detection fault signal, thereby driving the switch module 203 to disconnect the power connection.

[0064] In some embodiments, the over-temperature protection module 205 includes at least one temperature sensor, and the over-temperature self-check module includes a third comparison unit. The third comparison unit is coupled to the at least one temperature sensor and is triggered to generate an over-temperature self-check fault signal when at least one temperature sensor fails.

[0065] In some embodiments, the over-temperature self-test module further includes at least one voltage stabilizing component coupled to at least one temperature sensor and the third comparison unit. The at least one voltage stabilizing component is used to increase the trigger voltage of the third comparison unit.

[0066] Figure 3 FIG. 2 shows a schematic structural diagram of a leakage protection device according to an embodiment of the present invention. Figure 3As shown in FIG. 3 , the leakage protection device 300 includes a switch module 303, a leakage detection module 304, an over-temperature protection module 305, a drive module 306, and an over-temperature self-detection module 307. The switch module 303 is coupled between the input end 301 and the output end 302 of the current-carrying line, and controls the power connection between the input end 301 and the output end 302 of the current-carrying line. The current-carrying line may include a first current-carrying line (L) for connecting to the live line of the power grid and a second current-carrying line (N) for connecting to the neutral line of the power grid. The leakage detection module 304 detects the leakage current signal on the current-carrying line, and generates a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold. The over-temperature protection module 305 may, for example, include at least one temperature sensor, which detects the temperature of a specific component and / or a specific position, and generates an over-temperature fault signal when the temperature of a specific component and / or a specific position exceeds a preset threshold. The over-temperature self-detection module 307 is coupled to the over-temperature protection module 305, detects whether the over-temperature protection module 305 fails, and generates an over-temperature self-detection fault signal when the over-temperature protection module 305 fails. The driving module 306 is coupled to the switch module 303, the leakage detection module 304, the over-temperature protection module 305 and the over-temperature self-detection module 307. The driving module 306 receives the leakage fault signal, the over-temperature fault signal and the over-temperature self-detection fault signal, and drives the switch module 303 to disconnect the power connection in response to one or more of the leakage fault signal, the over-temperature fault signal and the over-temperature self-detection fault signal.

[0067] In some embodiments, the over-temperature protection module 305 includes at least one temperature sensor, and the over-temperature self-check module includes a third comparison unit. The third comparison unit is coupled to the at least one temperature sensor and is triggered to generate an over-temperature self-check fault signal when at least one temperature sensor fails.

[0068] In some embodiments, the over-temperature self-test module further includes at least one voltage stabilizing component coupled to at least one temperature sensor and the third comparison unit. The at least one voltage stabilizing component is used to increase the trigger voltage of the third comparison unit.

[0069] The leakage protection device 300 of this embodiment is provided with an over-temperature self-check module to perform self-check on the over-temperature protection function of the device, and cuts off the power connection when the over-temperature protection function fails, thereby further improving the safety of the leakage protection device 300.

[0070] Figure 4 A schematic principle diagram of a leakage protection device according to an embodiment of the present invention is shown. Figure 5A-5F Several schematic principle diagrams of the over-temperature protection module, the over-temperature self-detection module and / or the driving module are respectively shown.

[0071] First reference Figure 4 and Figure 5A The leakage protection device 400 is coupled between the input terminal LINE and the load device LOAD, and includes a switch module 403, a leakage detection module 404, an over-temperature protection module 405, a drive module 406 and a leakage self-detection module 407. The input terminal LINE is connected to the first plug blade and the second plug blade ( Figure 4 ). The leakage detection module 404 includes a leakage detection loop ZCT1, a leakage detection chip U1 and its peripheral circuits, and the first current-carrying line HOT 41 and the second current-carrying line WHITE 42 pass through the leakage detection loop ZCT1. The switch module 403 is used to control the power connection between the first current-carrying line 41 and the second current-carrying line 42. The over-temperature protection module 405 includes thermistors T1 (first temperature sensor) and T2 (second temperature sensor), resistors R28 (first voltage divider element) and R29 (second voltage divider element), diodes D6 (first isolation element) and D7 (second isolation element), transistor Q6 (first comparison unit) and light-emitting diode LED3. Thermistor T1 is arranged near the first plug blade and is used to detect the temperature near the first plug blade. Thermistor T2 is arranged near the second plug blade and is used to detect the temperature near the second plug blade. Thermistor T1 is connected in series with resistor R28, and thermistor T2 is connected in series with resistor R29 and then connected in parallel with thermistor T1 and resistor R28. The anode of diode D6 is connected to thermistor T1, and the cathode is connected to the emitter of transistor Q6. The anode of diode Q7 is connected to thermistor T2, and the cathode is also connected to the emitter of transistor Q6. Diodes D6 and D7 are used to isolate the temperature detection of thermistors T1 and T2. Pin 6 of leakage detection chip U1 is connected to an end N1 connected to thermistors T1 and T2, which is used to provide power for it. Pin 3 of leakage detection chip U1 is connected to the base of transistor Q6 to provide a reference voltage for it. Drive module 406 includes a switch drive element (such as coil RELAY), two thyristors Q1 and Q2 (first semiconductor element) and a reset switch RESET. Leakage self-test module 407 includes a trigger diode ZD1, a capacitor C13, a thyristor Q4 and some peripheral components. In other embodiments, the thyristor Q4 may be omitted, and the thyristor Q1 and / or Q2 may be shared with the driving module 406 , that is, the thyristor Q1 and / or Q2 may be connected in parallel with the capacitor C13 to provide a charge discharge path for the capacitor C13 when turned on.

[0072] Under normal circumstances, the current charges the capacitor C10 through HOT-R2-C6-DB1-C10. When the voltage at the upper end of the capacitor C10 rises to a level that makes the voltage divided by the resistor R10 and the resistor R18 higher than the trigger voltage of the thyristor Q3, the thyristor Q3 is turned on, and the current flows through the thyristor Q3 through HOT-R2-C6-DB1-R8-RELAY-LED1. The current changes in the coil RELAY, thus generating a magnetic field, driving the switch module 403 to close, and connecting the power connection between the input terminal LINE and the output terminal LOAD. The light-emitting diode LED1 lights up.

[0073] At the same time, the current powers the leakage detection chip U1 through HOT-R2-D1-R4, and generates a stable voltage at the power pin (pin 6) of the leakage detection chip U1. When there is leakage current on the first current-carrying line 41 or the second current-carrying line 42, the leakage detection ring ZCT1 detects the leakage current signal, and the secondary end generates a corresponding induction signal. The leakage detection ring ZCT1 is coupled to the leakage detection chip U1, and the induction signal is transmitted to the leakage detection chip U1 for processing. When the value of the processed leakage current is greater than the set threshold, pin 5 of the leakage detection chip U1 outputs a high level (leakage fault signal), otherwise it outputs a low level. The high level of pin 5 of the leakage detection chip U1 is provided to the control electrodes of thyristors Q1 and Q2 via diode D3 and resistors R13 and R16, triggering thyristors Q1 and / or Q2 to turn on. At this time, the current flows into the ground via R8-Q1 / Q2 and no longer flows through the coil RELAY, causing the coil RELAY to lose power, the magnetic field disappears, and the switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD. The user can reset by operating the reset switch RESET. Specifically, the reset switch RESET can be pressed, thyristors Q1 and Q2 are cut off, and the current flows through the thyristor Q3 again via HOT-R2-C6-DB1-R8-RELAY-LED1. The current changes again in the coil RELAY, generating a magnetic field, driving the switch module 403 to close, connecting the power connection between the input terminal LINE and the output terminal LOAD, and the leakage protection device 400 is reset successfully.

[0074] The leakage protection device 400 also has a leakage self-detection function. The current charges the capacitor C13 through HOT-D4-R17. As the voltage at the upper end of the capacitor C13 increases, the voltage at both ends of the trigger diode ZD1 increases accordingly. After a preset period of time, the voltage at the upper end of the capacitor C13 exceeds the trigger voltage of the trigger diode ZD1, the trigger diode ZD1 is turned on, and the current generates a simulated leakage current signal through the trigger diode ZD1-R7-ZCT1-ground, and charges the capacitor C8 through the resistor R9. In the normal working state of the leakage protection device 400, that is, the leakage detection module 404 and the driving module 406 are both working normally, the leakage detection ring ZCT1 detects the simulated leakage current signal, and its secondary end generates a corresponding induction signal and transmits it to the leakage detection chip U1. The pin 5 of the leakage detection chip U1 outputs a high level, and the current charges the capacitors C12 and C14 through the resistors R13 and R16. At the same time, the current triggers the thyristor Q4 to turn on through R15, and the capacitor C13 quickly releases the electricity through the thyristor Q4, and the upper end voltage decreases rapidly. When it drops to a trigger voltage less than the trigger voltage of the trigger diode ZD1, the trigger diode ZD1 is cut off, and the simulated leakage current signal cannot be generated, and the pin 5 of the leakage detection chip U1 stops outputting a high level. Due to the short trigger time, the upper end voltages of the capacitors C12, C14 and C8 are low at this time, which is not enough to trigger the thyristor Q1 and / or Q2 to turn on, and the switch module 403 remains in a closed state.

[0075] When the leakage detection module 404 fails and cannot detect the simulated leakage current signal, the pin 5 of the leakage detection chip U1 remains at a low level, and the thyristor Q4 cannot be triggered to turn on. The capacitor C13 cannot release the electricity through the thyristor Q4, and the trigger diode ZD1 is turned on for a long time, so that the voltage on the upper end of the capacitor C8 continues to rise, and the current continues to charge the capacitors C12 and C14 through the resistors R13 and R16 (i.e., a self-test fault signal is generated), so that the voltage on the upper end of the capacitors C12 and C14 rises to a certain level. If the driving module 406 works normally, the thyristors Q1 and Q2 are turned on, and the current flows into the ground through R8-Q1 / Q2, and no longer flows through the coil RELAY, so that the coil RELAY loses power, the magnetic field disappears, and the switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD.

[0076] The leakage protection device 400 also has an over-temperature protection function. At normal temperature, the resistance of thermistors T1 and T2 is relatively large, so the upper end voltage of resistors R28 and R29 is relatively low, which is lower than the base voltage of transistor Q6 (i.e., the reference voltage provided by pin 6 of the leakage detection chip U1), and transistor Q6 is cut off. When the temperature detected by thermistors T1 and / or T2 rises, its resistance decreases accordingly, and the upper end voltage of resistors R28 and / or R29 increases. When the temperature detected by thermistors T1 and / or T2 exceeds a preset threshold, the upper end voltage of resistors R28 and / or R29 (i.e., the over-temperature detection signal) exceeds the base voltage of transistor Q6, and transistor Q6 is turned on. The current flows through thermistors T1 / T2 and diodes D6 / D7 through transistor Q6, generating an over-temperature fault signal. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high.

[0077] Reference below Figure 4 and Figure 5B .exist Figure 5B In the schematic diagram, in addition to the over-temperature protection module 405, another part of the circuit of the driving module 406 is also shown. Figure 5A The difference is, Figure 5B The over-temperature protection module 405 in the embodiment also includes resistors R14 (third voltage-dividing element) and R24 (fourth voltage-dividing element) connected in series, which are connected to the base of transistor Q6 (first comparison unit) to provide base voltage to transistor Q6. In addition, the driving module 406 also includes a thyristor Q5 (second semiconductor element) connected to transistor Q6 and its peripheral circuits. One end (N2) of the resistor R22 and the light-emitting diode LED3 connected in parallel is connected to Figure 4 The resistor R8 in.

[0078] At normal temperature, the resistance of thermistors T1 and T2 is relatively large, so the voltage at the upper end of resistors R28 and R29 is relatively low, which is lower than the base voltage of transistor Q6 (i.e., the reference voltage provided by the voltage divider of resistors R14 and R24), and transistor Q6 is cut off. When the temperature detected by thermistors T1 and / or T2 rises, its resistance decreases accordingly, and the voltage at the upper end of resistors R28 and / or R29 increases.

[0079] When the temperature detected by thermistor T1 and / or T2 exceeds the preset threshold, the upper terminal voltage of resistor R28 and / or R29 (i.e., the over-temperature detection signal) exceeds the base voltage of transistor Q6, and transistor Q6 is turned on. Current flows through thermistor T1 / T2 and diode D6 / D7 through transistor Q6, generating an over-temperature fault signal and triggering thyristor Q5 to turn on. Most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. Light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through coil RELAY, the magnetic field weakens and the switch module 403 cannot be kept closed. The switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD.

[0080] Since the reset switch RESET is not connected in parallel with the thyristor Q5, even if the user presses the reset switch RESET, the thyristor Q5 cannot be turned off, and most of the current will not flow through the coil RELAY again. The user must remove the product from the power port, detect the heating condition, and insert it into the power port again. The leakage protection device 400 can be reset successfully after it is powered again, so that the switch module 403 can reconnect the power connection between the input terminal LINE and the output terminal LOAD.

[0081] Reference below Figure 4 and Figure 5C .and Figure 5B The difference is, Figure 5C The over-temperature protection module 405 in the embodiment includes two transistors Q6 (first comparison unit) and Q8 (second comparison unit). The emitter of transistor Q6 is connected to the thermistor T1, and the emitter of transistor Q8 is connected to the thermistor T2. Resistors R14 (third voltage divider element) and R24 (fourth voltage divider element) are connected to the bases of transistors Q6 and Q8 to provide base voltages to transistors Q6 and Q8. Figure 5C The diodes D6 and D7 (isolation elements) are not provided, but the independence of the temperature detection of thermistors T1 and T2 is ensured by providing transistors Q6 and Q8 for thermistors T1 and T2 respectively.

[0082] At normal temperature, the resistance of thermistors T1 and T2 is large, so the upper end voltage of resistors R28 and R29 is low, lower than the base voltage of transistors Q6 and Q8 (i.e., the reference voltage provided by the voltage divider of resistors R14 and R24), and transistors Q6 and Q8 are cut off.

[0083] When the temperature detected by thermistor T1 rises, its resistance decreases accordingly, and the upper voltage of resistor R28 increases. When the temperature detected by thermistor T1 exceeds the preset threshold, the upper voltage of resistor R28 (i.e., the over-temperature detection signal) exceeds the base voltage of transistor Q6, and transistor Q6 is turned on. The current flows through thermistor T1 through transistor Q6, generating an over-temperature fault signal and triggering the thyristor Q5 to turn on. Most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through the coil RELAY, the magnetic field is weakened, and the switch module 403 cannot be kept closed, and the switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD.

[0084] Similarly, when the temperature detected by thermistor T2 rises, its resistance decreases accordingly, and the upper voltage of resistor R29 increases. When the temperature detected by thermistor T2 exceeds the preset threshold, the upper voltage of resistor R29 (i.e., the over-temperature detection signal) exceeds the base voltage of transistor Q8, and transistor Q8 is turned on. The current flows through thermistor T2 through transistor Q8, generating an over-temperature fault signal and triggering the thyristor Q5 to turn on. Most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through the coil RELAY, the magnetic field is weakened, and the switch module cannot be kept closed, and the switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD.

[0085] Since the reset switch RESET is not connected in parallel with the thyristor Q5, even if the user presses the reset switch RESET, the thyristor Q5 cannot be turned off, and the current will not flow through the coil RELAY again. The user must remove the product from the power port, detect the heating condition, and insert it into the power port again. The leakage protection device 400 can be reset successfully after it is powered again, so that the switch module 403 can reconnect the power connection between the input terminal LINE and the output terminal LOAD.

[0086] Reference below Figure 4 and Figure 5D .and Figure 5B compared to, Figure 5DThe schematic diagram also includes an over-temperature self-test module 408, which is coupled to the over-temperature protection module 405 and the driving module 406. The over-temperature self-test module 408 includes a transistor Q7 (third comparison unit), diodes D5 (third isolation element) and D8 (fourth isolation element) and voltage-dividing resistors R26 and R30 connected in series. The anodes of diodes D5 and D8 are both connected to the base of transistor Q7, and the cathodes are connected to the thermistors T1 and T2 and the anodes of diodes D6 and D7. Resistors R26 and R30 provide emitter voltage for transistor Q7 after voltage division. When thermistor T1 and / or T2 has an open circuit fault, the base of transistor Q7 is grounded through diode D5 and / or D8 and resistor R28 and / or R29, which is lower than the emitter voltage of transistor Q7 (i.e., the reference voltage provided by the voltage divider of resistors R26 and R30). The current triggers transistor Q7 to turn on through R26-Q7-D5 / D8-R28 / R29, and at the same time, the current (over-temperature self-test fault signal) triggers thyristor Q5 to turn on through R26-Q7, and most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through coil RELAY, the magnetic field is weakened, and the switch module 403 cannot be kept closed. The switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD, thereby realizing the over-temperature self-test function.

[0087] Reference below Figure 4 and Figure 5E .and Figure 5D compared to, Figure 5EThe over-temperature self-test module 408 also includes a resistor R31 and a Zener diode ZD2 (a first voltage-stabilizing component) connected in series, and a resistor R32 and a Zener diode ZD3 (a second voltage-stabilizing component) connected in series. Resistor R31 is connected to the thermistor T1, and resistor R32 is connected to the thermistor T2. Since the Zener diodes ZD2 and ZD3 have a larger impedance when the current is small and a smaller impedance when the current is large, when the thermistors T1 and / or T2 detect a lower temperature (such as -35°C), the Zener diodes ZD2 and / or ZD3 ensure that the upper end voltage of the resistors R31 and / or R31 is higher. The emitter voltage of transistor Q7 is set at a higher voltage, and transistor Q7 remains cut off. When thermistor T1 and / or T2 has an open circuit fault, the base of transistor Q7 is grounded through diode D5 and / or D8 and resistor R28 and / or R29, which is lower than the emitter voltage of transistor Q7 (i.e., the reference voltage provided by the voltage divider of resistors R26 and R30). The current triggers transistor Q7 to turn on through R26-Q7-D5 / D8-R28 / R29, and at the same time, the current (over-temperature self-test fault signal) triggers thyristor Q5 to turn on through R26-Q7, and most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through coil RELAY, the magnetic field is weakened, and the switch module 403 cannot be kept closed. The switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD, thereby realizing the over-temperature self-test function. That is to say, the first voltage stabilizing component and the second voltage stabilizing component can set the upper end voltage of the resistors R31 and / or R32 at a higher level, so that the transistor Q7 can be reliably turned on when an open circuit failure occurs in T1 and / or T2, thereby improving the self-test accuracy and reliability of the self-test function of the over-temperature self-test module 408.

[0088] Reference below Figure 4 and Fig. 5F Compared with 5B, Fig. 5F The directions of the emitter and base of transistor Q6, thermistors T1 / T2, resistors R28 / R29, and diodes D6 / D7 are swapped.

[0089] At normal temperature, the resistance of thermistors T1 and T2 is relatively large, so the voltage at the lower end of resistors R28 and R29 is relatively high, which is higher than the emitter voltage of transistor Q6 (i.e., the voltage provided by the voltage divider of resistors R14 and R24), and transistor Q6 is cut off. When the temperature detected by thermistors T1 and / or T2 rises, its resistance decreases accordingly, and the voltage at the lower end of resistors R28 and / or R29 decreases.

[0090] When the temperature detected by thermistor T1 and / or T2 exceeds the preset threshold, the lower end voltage of resistor R28 and / or R29 (i.e., the over-temperature detection signal) is lower than the emitter voltage of transistor Q6, transistor Q6 is turned on, an over-temperature fault signal is generated, and the thyristor Q5 is triggered to turn on. Most of the current flows into the ground through HOT-R2-C6-DB1-LED3-R25-Q5. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high. At the same time, since most of the current no longer flows through the coil RELAY, the magnetic field is weakened, and the switch module 403 cannot be kept closed. The switch module 403 disconnects the power connection between the input terminal LINE and the output terminal LOAD.

[0091] Figure 6 A schematic principle diagram of a leakage protection device according to an embodiment of the present invention is shown.

[0092] refer to Figure 6 and Figure 5A The leakage protection device 500 is coupled between the input terminal LINE and the load device LOAD, and includes a switch module 503, a leakage detection module 504 and a driving module 506. The leakage protection device 500 also includes Figure 5A The over-temperature protection module 405 in the embodiment. The input terminal LINE is connected to the first plug blade and the second plug blade ( Figure 6 51. The leakage detection module 504 includes a leakage detection loop ZCT1, a leakage detection chip U1 and its peripheral circuits. The first current-carrying line HOT 51 and the second current-carrying line WHITE 52 pass through the leakage detection loop ZCT1. The switch module 503 includes a reset switch RESET, which is used to control the power connection between the first current-carrying line 51 and the second current-carrying line 52. The thermistor T1 in the over-temperature protection module 405 is also arranged near the first plug blade and is used to detect the temperature near the first plug blade. The thermistor T2 is also arranged near the second plug blade and is used to detect the temperature near the second plug blade. Pin 3 of the leakage detection chip U1 is connected to one end N1 where the thermistor T1 and T2 are connected, so as to provide power therefor. Pin 4 of the leakage detection chip U1 is connected to the base of the transistor Q6 to provide it with a reference voltage. The driving module 506 includes a switch driving element (such as a coil RELAY) and a thyristor Q1 (a first semiconductor element).

[0093] Under normal circumstances, the current is grounded through HOT-C7-DB-RELAY-U1, the coil RELAY and the leakage detection chip U1 are powered, and the power pin (pin 3) of the leakage detection chip U1 generates a stable voltage. The coil RELAY generates a magnetic field, and the RESET switch module 503 is manually pressed to keep it closed, connecting the power connection between the input terminal LINE and the output terminal LOAD.

[0094] When there is leakage current on the first current-carrying line 51 or the second current-carrying line 52, the leakage detection ring ZCT1 detects the leakage current signal, and the secondary end generates a corresponding induction signal. The leakage detection ring ZCT1 is coupled to the leakage detection chip U1, and the induction signal is transmitted to the leakage detection chip U1 for processing. When the value of the processed leakage current is greater than the set threshold, the pin 1 of the leakage detection chip U1 outputs a high level (leakage fault signal), otherwise it outputs a low level. The high level of the pin 1 of the leakage detection chip U1 is provided to the control electrode of the thyristor Q1 via the resistor R4, triggering the thyristor Q to turn on. At this time, the current flows into the ground through HOT-C7-DB-Q1 and no longer flows through the coil RELAY, causing the coil RELAY to lose power, the magnetic field disappears, and the switch module 503 disconnects the power connection between the input terminal LINE and the output terminal LOAD. The reset switch RESET is a mechanical switch, and the user can reset by operating the reset switch RESET.

[0095] The leakage protection device 400 also has an over-temperature protection function. At normal temperature, the resistance of thermistors T1 and T2 is relatively large, so the upper end voltage of resistors R28 and R29 is relatively low, which is lower than the base voltage of transistor Q6 (i.e., the reference voltage provided by pin 4 of the leakage detection chip U1), and transistor Q6 is cut off. When the temperature detected by thermistors T1 and / or T2 rises, its resistance decreases accordingly, and the upper end voltage of resistors R28 and / or R29 increases. When the temperature detected by thermistors T1 and / or T2 exceeds a preset threshold, the upper end voltage of resistors R28 and / or R29 (i.e., the over-temperature detection signal) exceeds the base voltage of transistor Q6, and transistor Q6 is turned on. The current flows through thermistors T1 / T2 and diodes D6 / D7 through transistor Q6, generating an over-temperature fault signal. The light-emitting diode LED3 is lit, prompting the user that the product temperature is too high.

[0096] Similar to the leakage protection device 400, in other embodiments, the leakage protection device 500 may include: Figure 5B The over-temperature protection module 405 and the partial drive module 406 shown in FIG. Figure 5C The over-temperature protection module 405 and the partial drive module 406 shown in FIG. Figure 5D The over-temperature protection module 405, the partial drive module 406 and the over-temperature self-test module 408 shown in FIG. Figure 5E The over-temperature protection module 405, the partial drive module 406 and the over-temperature self-test module 408 shown in FIG. Fig. 5F The over-temperature protection module 405 and part of the driving module 406 are shown in FIG. Their over-temperature protection function, driving function and over-temperature self-detection function (if any) can refer to the description above and will not be repeated here.

[0097] The present invention further proposes an electrical connection device, comprising: a housing; and a leakage protection device according to any one of the above embodiments, wherein the leakage protection device is accommodated in the housing.

[0098] In addition, the present invention also proposes an electrical appliance, including: a load device; and an electrical connection device, which is coupled to the load device and is used to supply power to the load device, and the electrical connection device includes any one of the leakage protection devices in the above embodiments.

[0099] Therefore, although the present invention is described with reference to specific examples, wherein these specific examples are intended to be illustrative only and not limiting of the present invention, it is obvious to those skilled in the art that the disclosed embodiments may be changed, added or deleted without departing from the spirit and scope of the present invention.

Claims

1. A leakage protection device, comprising: a switch module coupled between an input end and an output end of a current carrying line and configured to control a power connection between the input end and the output end, wherein the input end of the current carrying line is connected to a first plug blade and a second plug blade; a leakage detection module, configured to detect a leakage current signal on the current-carrying line, and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, comprising a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is disposed close to the first plug blade and configured to detect a temperature near the first plug blade, and the second temperature sensor is disposed close to the second plug blade and configured to detect a temperature near the second plug blade, wherein the over-temperature protection module is configured to generate an over-temperature fault signal when the temperature detected by the first temperature sensor and / or the second temperature sensor exceeds a preset threshold; and The driving module is coupled to the switch module and the leakage detection module and is configured to receive the leakage fault signal and drive the switch module to disconnect the power connection in response to the leakage fault signal.

2. The leakage protection device according to claim 1, wherein: The over-temperature protection module also includes: a first voltage dividing element connected in series with the first temperature sensor; a second voltage dividing element connected in series with the second temperature sensor; A first comparison unit is coupled to the first voltage dividing element and the second voltage dividing element, wherein: When the temperature detected by the first temperature sensor and / or the second temperature sensor exceeds the preset threshold, the first voltage divider element and / or the second voltage divider element provides an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate the over-temperature fault signal.

3. The leakage protection device according to claim 2, wherein: The over-temperature protection module also includes: a first isolation element coupled between the first temperature sensor and the first comparison unit; and A second isolation element is coupled between the second temperature sensor and the first comparison unit, wherein: The first isolation element and the second isolation element are configured to isolate temperature detection signals of the first temperature sensor and the second temperature sensor.

4. The leakage protection device according to claim 3, wherein: The first isolation element and the second isolation element are diodes respectively.

5. The leakage protection device according to claim 2, wherein: The leakage protection module comprises a leakage detection chip, and the leakage detection chip is coupled to the first comparison unit to provide a reference voltage to the first comparison unit; or The over-temperature protection module further includes a third voltage dividing element and a fourth voltage dividing element connected in series, wherein the third voltage dividing element and the fourth voltage dividing element are coupled to the first comparing unit and are configured to provide a reference voltage to the first comparing unit.

6. The leakage protection device according to claim 1, wherein: The over-temperature protection module also includes: a first voltage dividing element connected in series with the first temperature sensor; a second voltage dividing element connected in series with the second temperature sensor; a first comparison unit coupled to the first voltage dividing element; A second comparison unit is coupled to the second voltage dividing element, wherein: When the temperature detected by the first temperature sensor exceeds the preset threshold, the first voltage divider element provides an over-temperature detection signal to the first comparison unit, thereby causing the first comparison unit to generate the over-temperature fault signal; and / or When the temperature detected by the second temperature sensor exceeds the preset threshold, the second voltage dividing element provides the over-temperature detection signal to the second comparing unit, thereby causing the second comparing unit to generate the over-temperature fault signal.

7. The leakage protection device according to any one of claims 1 to 6, wherein: The driving module is also coupled to the over-temperature protection module, and is further configured to receive the over-temperature fault signal, and drive the switch module to disconnect the power connection in response to the over-temperature fault signal.

8. The leakage protection device according to claim 7, wherein: The driving module also includes: at least one first semiconductor element coupled to the leakage detection module and configured to receive the leakage fault signal and change a switch state in response to the leakage fault signal; and At least one second semiconductor element is coupled to the over-temperature protection module and is configured to receive the over-temperature fault signal and change a switch state in response to the over-temperature fault signal.

9. The leakage protection device according to claim 7, wherein: The driving module also includes: A reset switch, which can be operated to: drive the switch module to reconnect the power connection when the drive module drives the switch module to disconnect the power connection in response to the leakage fault signal, and maintain the disconnected state of the power connection when the drive module drives the switch module to disconnect the power connection in response to the over-temperature fault signal.

10. The leakage protection device according to any one of claims 1 to 6, further comprising: an over-temperature self-detection module, which is coupled to the over-temperature protection module and the driving module and is configured to detect whether the over-temperature protection module fails and generate an over-temperature self-detection fault signal when the over-temperature protection module fails, and, The driving module is further configured to receive the over-temperature self-test fault signal, and drive the switch module to disconnect the power connection in response to the over-temperature self-test fault signal.

11. The leakage protection device according to claim 10, wherein: The over-temperature self-test module includes a third comparison unit, which is coupled to the first temperature sensor and the second temperature sensor and is configured to be triggered to generate the over-temperature self-test fault signal when the first temperature sensor and the second temperature sensor fail.

12. The leakage protection device according to claim 11, wherein: The over-temperature self-test module also includes: A first voltage stabilizing component coupled to the first temperature sensor and the third comparing unit; A second voltage stabilizing component is coupled to the second temperature sensor and the third comparing unit, wherein: The first voltage stabilizing component and the second voltage stabilizing component are configured to increase a trigger voltage of the third comparing unit.

13. The leakage protection device according to claim 11 or 12, wherein: The over-temperature self-test module also includes: a third isolation element coupled between the first temperature sensor and the third comparison unit; and a fourth isolation element coupled between the second temperature sensor and the third comparison unit, wherein: The third isolation element and the fourth isolation element are configured to isolate temperature detection signals of the first temperature sensor and the second temperature sensor.

14. The leakage protection device according to claim 1, further comprising: a leakage self-check module, which is coupled to the leakage detection module and the driving module and is configured to periodically generate the simulated leakage current signal to detect whether the leakage detection module fails, and to generate a leakage self-check fault signal when the leakage detection module fails, and, The driving module is further configured to receive the leakage self-test fault signal, and drive the switch module to disconnect the power connection in response to the leakage self-test fault signal.

15. A leakage protection device, comprising: a switch module coupled between an input end and an output end of the current-carrying line and configured to control a power connection between the input end and the output end; a leakage detection module, configured to detect a leakage current signal on the current-carrying line, and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, which is configured to detect the temperature of a specific component and / or a specific location, and generate an over-temperature fault signal when the temperature of the specific component and / or the specific location exceeds a preset threshold; as well as A driving module, coupled to the switch module, comprising: at least one first semiconductor element, coupled to the leakage detection module and configured to receive the leakage fault signal and change a switch state in response to the leakage fault signal, thereby driving the switch module to disconnect the power connection; as well as At least one second semiconductor element is coupled to the over-temperature protection module and is configured to receive the over-temperature fault signal and change a switch state in response to the over-temperature fault signal, thereby driving the switch module to disconnect the power connection.

16. The leakage protection device according to claim 15, wherein: The driving module also includes: A reset switch, which can be operated to: drive the switch module to reconnect the power connection when the at least one first semiconductor element drives the switch module to disconnect the power connection in response to the leakage fault signal, and keep the power connection in a disconnected state when the at least one second semiconductor element drives the switch module to disconnect the power connection in response to the over-temperature fault signal.

17. The leakage protection device according to claim 15 or 16, further comprising: an over-temperature self-detection module, which is coupled to the over-temperature protection module and the driving module and is configured to detect whether the over-temperature protection module fails and generate an over-temperature self-detection fault signal when the over-temperature protection module fails, and, The at least one second semiconductor element is further configured to receive the over-temperature self-test fault signal and change a switch state in response to the over-temperature self-test fault signal, thereby driving the switch module to disconnect the power connection.

18. The leakage protection device according to claim 17, wherein: The over-temperature protection module includes at least one temperature sensor, and the over-temperature self-test module includes a third comparison unit, which is coupled to the at least one temperature sensor and configured to be triggered to generate the over-temperature self-test fault signal when the at least one temperature sensor fails.

19. The leakage protection device according to claim 18, wherein: The over-temperature self-test module further includes at least one voltage stabilizing component coupled to the at least one temperature sensor and the third comparing unit, wherein the at least one voltage stabilizing component is configured to increase a trigger voltage of the third comparing unit.

20. A leakage protection device, comprising: a switch module coupled between an input end and an output end of the current-carrying line and configured to control a power connection between the input end and the output end; a leakage detection module, configured to detect a leakage current signal on the current-carrying line, and generate a leakage fault signal when the leakage current signal is detected or when the leakage current signal exceeds a preset threshold; an over-temperature protection module, which is configured to detect the temperature of a specific component and / or a specific location, and generate an over-temperature fault signal when the temperature of the specific component and / or the specific location exceeds a preset threshold; an over-temperature self-detection module, which is coupled to the over-temperature protection module and is configured to detect whether the over-temperature protection module fails and generate an over-temperature self-detection fault signal when the over-temperature protection module fails; as well as A driving module is coupled to the switch module, the leakage detection module, the over-temperature protection module and the over-temperature self-test module, and is configured to receive the leakage fault signal, the over-temperature fault signal and the over-temperature self-test fault signal, and drive the switch module to disconnect the power connection in response to one or more of the leakage fault signal, the over-temperature fault signal and the over-temperature self-test fault signal.

21. The leakage protection device according to claim 20, wherein: The over-temperature protection module includes at least one temperature sensor, and the over-temperature self-test module includes a third comparison unit, which is coupled to the at least one temperature sensor and configured to be triggered to generate the over-temperature self-test fault signal when the at least one temperature sensor fails.

22. The leakage protection device according to claim 21, wherein: The over-temperature self-test module further includes at least one voltage stabilizing component coupled to the at least one temperature sensor and the third comparing unit, wherein the at least one voltage stabilizing component is configured to increase a trigger voltage of the third comparing unit.

23. An electrical connection device, comprising: case; as well as The leakage protection device according to any one of claims 1 to 22, wherein the leakage protection device is accommodated in the shell.

24. An electrical appliance, comprising: Load equipment; as well as The electrical connection device according to claim 23, coupled to the load device, is used to supply power to the load device.

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