Backup protector of surge protection device

Abstract

The invention discloses a backup protector of a surge protection device, which relates to the technical field of surge protection and comprises a base provided with an SPD (surge protection device) module jack, a first terminal, a second terminal, a backup protection module and a protection execution mechanism. The backup protection module comprises a metal gap and an ignition circuit. The metal gap is provided with a second gap piece, a first gap piece connected with the first terminal and an arc chute. The ignition circuit is composed of a discharge tube, a contact piece and a flexible circuit board, one end of the discharge tube is connected with the flexible circuit board, a wire extends to form a discharge head, the discharge head is close to the first gap piece, and the other end is connected with the second gap piece through the contact piece. And the protection execution mechanism cuts off the ignition circuit when the metal gap temperature exceeds a threshold value. The SPD module is inserted into the jack and then is connected in series with the metal gap to the second terminal. According to the invention, through the large discharge capability and the follow current interruption capability of the discharge gap, the circuit can be cut off to prevent fire disasters in case of overheating, and the protection reliability and the maintenance convenience are improved.

Description

Technical Field

[0001] This invention relates to the field of surge protection technology, and more particularly to a backup protector for a surge protector. Background Technology

[0002] In the field of surge protection for low-voltage power supply systems, varistors are widely used as core protection devices due to their stable performance. However, this device presents significant safety hazards in practical use. Firstly, varistors deteriorate over time, leading to a gradual increase in leakage current. This increased leakage current causes the device to continuously heat up; if the heat generation exceeds its heat dissipation capacity, the temperature will accumulate and rise. In the event of a failure of the varistor's internal tripping mechanism, this sustained temperature rise could ultimately lead to a fire.

[0003] On the other hand, when a surge protector is subjected to transient overvoltages exceeding its withstand capacity, especially power frequency overvoltages, the varistor may be instantly broken down, creating a near-short circuit. If the short-circuit current is large and not interrupted in time, the enormous energy accumulated in a short period cannot be released through heat dissipation, easily leading to an explosion of the varistor. Therefore, adding backup protection devices to varistor-type surge protectors has become a key measure to prevent their fire and explosion risks. However, currently common backup protection methods, such as fuses, circuit breakers, and some dedicated backup protectors, are still difficult to comprehensively and effectively address both leakage current heating and fire and short-circuit explosion risks simultaneously in practical applications. Summary of the Invention

[0004] The technical problem to be solved by the embodiments of the present invention is: how to provide a backup protection device for a varistor-type surge protector that can simultaneously and effectively prevent the risk of fire caused by its increased leakage current and the risk of explosion caused by its short circuit breakdown.

[0005] To address the aforementioned problems, embodiments of the present invention provide a backup protector for a surge protector, comprising:

[0006] The base is equipped with sockets for mounting SPD modules;

[0007] The first terminal is disposed on the surface of the base;

[0008] The second terminal is disposed on the surface of the base;

[0009] A backup protection module is installed inside the base, including a metal gap and an ignition circuit;

[0010] The metal gap includes a first gap plate, a second gap plate, and an arc-extinguishing grid, wherein the first gap plate is electrically connected to the first terminal;

[0011] The ignition circuit includes a discharge tube, a contact piece, and a flexible circuit board. One end of the discharge tube is connected to the flexible circuit board. A wire connected to the discharge tube in the flexible circuit board extends to form a discharge head. The discharge head is close to the first gap piece. The other end of the discharge tube is electrically connected to the second gap piece through the contact piece.

[0012] A protective actuator is used to cut off the ignition circuit when the temperature of the metal gap reaches a preset threshold.

[0013] When the SPD module is inserted into the socket, the SPD module is connected in series between the metal gap and the second terminal.

[0014] A further technical solution is that the protection actuator includes a temperature sensor and an energy storage drive device. The temperature sensor is located on the first gap, and the energy storage drive device is mechanically coupled to the temperature sensor. When the temperature detected by the temperature sensor reaches a preset threshold, the energy storage drive device is triggered and cuts off the ignition circuit.

[0015] A further technical solution is that the temperature sensor is a bimetallic strip, the bimetallic strip is connected to the first gap plate, and the bimetallic strip is provided with a hook;

[0016] The energy storage drive device includes a sliding insert and an elastic element, wherein the elastic element abuts between the sliding insert and the support.

[0017] The sliding insert is provided with a slot, wherein the hook engages with the slot. When the temperature detected by the bimetallic strip reaches a preset threshold, the bimetallic strip deforms, causing the hook to disengage from the slot. The elastic element drives the sliding insert to be inserted between the contact piece and the discharge tube to cut off the ignition circuit.

[0018] A further technical solution is that the backup protection module also includes an indicator, which is connected to the sliding insert. When the sliding insert is inserted between the contact piece and the discharge tube, it synchronously drives the indicator to change its indication state.

[0019] A further technical solution is that a remote signaling switch is provided in the base. When the sliding insert is inserted between the contact piece and the discharge tube, the indicator is simultaneously driven to trigger the remote signaling switch to change the electrical state.

[0020] A further technical solution is that the backup protection module also includes a manual operation device, which includes a handle connected to the sliding insert. An operation window is provided on the upper shell of the backup protection module, and the handle extends to the outside of the shell through the operation window. The sliding insert and the indicator can be reset by manually operating the handle.

[0021] A further technical solution is that the first spacer is provided with a through hole, and an insulating frame is embedded in the through hole. The discharge head is inserted into the insulating frame to extend into the through hole of the first spacer, thereby getting close to the first spacer.

[0022] A further technical solution is that the bottom shell of the backup protection module is provided with a guide groove to guide the movement direction of the sliding insert, and the sliding insert is at least partially embedded in the guide groove.

[0023] A further technical solution is that the upper shell of the backup protection module is provided with a contact window and an insertion hole. One end of the contact piece passes through the contact window and abuts against the discharge tube, and the other end of the contact piece passes through the insertion hole and abuts against the second spacer.

[0024] Compared with the prior art, the technical effects achieved by the embodiments of the present invention include:

[0025] This invention provides a backup protector for a surge protector, comprising: a base with a socket for mounting an SPD module; a first terminal on the surface of the base; a second terminal on the surface of the base; a backup protection module installed within the base, including a metal gap and an ignition circuit; the metal gap including a first gap plate, a second gap plate, and an arc-extinguishing grid, the first gap plate being electrically connected to the first terminal; the ignition circuit including a discharge tube, a contact plate, and a flexible circuit board, one end of the discharge tube being connected to the flexible circuit board, a wire connecting the discharge tube extending from the flexible circuit board to form a discharge head, the discharge head extending into the first gap plate close to the first gap plate, and the other end of the discharge tube being electrically connected to the second gap plate through the contact plate; and a protection actuator for cutting off the ignition circuit when the temperature of the metal gap reaches a preset threshold; wherein, when the SPD module is inserted into the socket, the SPD module is connected in series between the metal gap and the second terminal. This invention, through the cooperation of a built-in metal gap, arc-extinguishing grid, and ignition circuit, forms a path to discharge current during overvoltage and can quickly cut off overload power frequency current and leakage current. Simultaneously, an independent protection actuator is incorporated to respond to overheating of the metal gap and cut off the ignition circuit, preventing fires caused by heat accumulation. Furthermore, the base features sockets for plug-and-play SPD modules, enabling rapid replacement of faulty modules and significantly improving the safety, reliability, and ease of maintenance of the surge protection system. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0029] Figure 1 This is a structural block diagram of a backup protector for a surge protector according to Embodiment 1 of the present invention;

[0030] Figure 2 This is an exploded view of a backup protector for a surge protector according to Embodiment 1 of the present invention;

[0031] Figure 3 This is a top view of the backup protector of a surge protector according to Embodiment 1 of the present invention after the top cover has been removed;

[0032] Figure 4 This is a schematic diagram of the internal structure of a backup protector for a surge protector according to Embodiment 1 of the present invention;

[0033] Figure 5 This is a schematic diagram of the upper housing of a backup protector for a surge protector according to Embodiment 1 of the present invention;

[0034] Figure 6 This is a circuit diagram of the ignition circuit of the backup protector of a surge protector according to Embodiment 1 of the present invention;

[0035] Figure 7 This is a schematic diagram of the ignition circuit of the backup protector of a surge protector according to Embodiment 1 of the present invention;

[0036] Figure 8 This is a schematic diagram showing the cooperation relationship between the contact piece and the sliding plate of the backup protector of a surge protector according to Embodiment 1 of the present invention;

[0037] Figure 9This is an exploded view of a backup protector for a surge protector proposed in Embodiment 2 of the present invention.

[0038] Figure Labels

[0039] Base 10, first socket 11, second socket 12, first terminal 13, second terminal 14, spare terminal 15, backup protection module 20, metal gap 21, ignition circuit 22, first gap plate 211, second gap plate 212, discharge tube 221, contact plate 222, flexible circuit board 223, discharge head 224, SPD module 30, temperature sensor 40, energy storage drive device 50, hook 41, sliding insert 51, elastic element 52, slot 511, indicator 60, remote signaling switch 70, manual operation device 80, handle 81, upper shell 23, bottom shell 24, operation window 231, insulating frame 90, guide groove 241, contact window 232, insertion hole 233, connecting piece 100, mounting groove 200, arc extinguishing grid 300, N-PE surge protector module 400. Detailed Implementation

[0040] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Similar component reference numerals in the drawings represent similar components. Obviously, the embodiments described below are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0041] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0042] It should also be understood that the terminology used in this specification of embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the embodiments of the invention. As used in this specification of embodiments of the invention and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0043] Example 1

[0044] See Figures 1-8 Embodiment 1 of the present invention proposes a backup protector for a surge protector, comprising:

[0045] The base 10 is provided with a socket for mounting the SPD module 30;

[0046] The first terminal 13 is disposed on the surface of the base 10;

[0047] The second terminal 14 is disposed on the surface of the base 10;

[0048] The backup protection module 20 is installed in the base 10 and includes a metal gap 21 and an ignition circuit 22.

[0049] The metal gap 21 includes a first gap plate 211, a second gap plate 212 and an arc-extinguishing grid 300, wherein the first gap plate 211 is electrically connected to the first terminal 13;

[0050] The ignition circuit 22 includes a discharge tube 221, a contact piece 222, and a flexible circuit board 223. One end of the discharge tube 221 is connected to the flexible circuit board 223. A wire connecting the discharge tube 221 extends in the flexible circuit board 223 to form a discharge head 224. The discharge head 224 is close to the first spacer 211. The other end of the discharge tube 221 is electrically connected to the second spacer 212 through the contact piece 222.

[0051] The protective actuator is used to cut off the ignition circuit 22 when the temperature of the metal gap 21 is detected to reach a preset threshold.

[0052] When the SPD module 30 is inserted into the socket, the SPD module 30 is connected in series between the metal gap 21 and the second terminal 14.

[0053] In specific implementation, the backup protector uses the base 10 as the main body for installation and support. The base 10 is provided with a socket for installing an external SPD module 30. Specifically, connecting an SPD module 30 requires two sockets, namely a first socket 11 and a second socket 12. The first socket 11 and the second socket 12 are respectively used to connect to the two ends of the SPD module 30. The first socket 11 is connected to the second gap piece 212 through the connecting piece 100, and the second socket 12 is connected to the second terminal 14.

[0054] Furthermore, the first terminal 13 and the second terminal 14 are disposed on the surface of the base 10, serving as interfaces for the entire device to make electrical connections to the outside.

[0055] Furthermore, it also includes a spare terminal 15, which is electrically connected in parallel with the first terminal 13 (input terminal). Its core function is to provide an access point for the surge protector in a Kelvin connection mode. In Kelvin connection mode, the main power supply line of the protected equipment and the output line after protection can be independently connected to the first terminal 13 and the spare terminal 15, respectively. This design can remove the additional voltage drop generated by the surge current across the input line impedance from the terminal voltage of the protected equipment, thereby significantly reducing the residual voltage (i.e., protection voltage level) actually borne by the equipment during current discharge. Therefore, the setting of the spare terminal 15 optimizes the potential distribution under high-frequency, high-current impacts, improving the actual protection effect of the surge protector.

[0056] Furthermore, the backup protection module 20, as a core functional unit, is installed inside the base 10. Its main structure includes a metal gap 21 and an ignition circuit 22. The metal gap 21 specifically includes a first gap plate 211, a second gap plate 212, and an arc-extinguishing grid 300. The first gap plate 211 establishes an electrical connection with the first terminal 13, thereby connecting to the front-end circuit. The first gap plate 211 and the second gap plate 212 are spaced apart, and the arc-extinguishing grid 300 is disposed between the first gap plate 211 and the second gap plate 212.

[0057] The ignition circuit 22 is crucial for achieving active ignition in the gap, and it consists of a discharge tube 221, a contact piece 222, and a flexible circuit board 223. The flexible circuit board 223 not only carries the electronic circuitry, but a section of its lead wire connected to the discharge tube 221 is specially extended and shaped into a protruding discharge head 224. This discharge head 224 is precisely positioned and extends into the through-hole of the first gap piece 211, thus closely adhering to it. One end of the discharge tube 221 is electrically and physically connected to the flexible circuit board 223, while its other end, through the elastic contact piece 222, establishes a reliable electrical connection with the second gap piece 212, thereby forming a complete current path.

[0058] Furthermore, the backup protector is also equipped with a protection actuator, the core function of which is to monitor the temperature of the metal gap 21. Once the temperature reaches a preset threshold, the actuator will execute the command to cut off the ignition circuit 22. When the external SPD module 30 is inserted into the socket of the base 10, the SPD module 30 is electrically connected in series between the metal gap 21 and the second terminal 14, thereby forming a series protection relationship between the entire backup protector and the SPD module 30.

[0059] It should be noted that the ignition circuit 22 operates based on the synergistic effect of its components under overvoltage conditions to actively guide and safely discharge surge energy. This circuit mainly consists of a discharge tube 221, a flexible circuit board 223 and its extended discharge head 224, and contact pieces 222.

[0060] Under normal operating conditions, the voltage applied across the system is the power frequency voltage, which is lower than the breakdown voltage of the discharge tube 221 and also lower than the breakdown threshold of the air gap between the discharge head 224 and the first spacer 211. At this time, the discharge tube 221 is in a high-resistance insulation state, and the air gap between the discharge head 224 and the first spacer 211 also remains insulated. No current flows through the entire ignition circuit 22, and it is in a static standby mode.

[0061] When a surge or overvoltage event occurs, such as a lightning strike or grid overvoltage, a transient high voltage with an amplitude much higher than the power frequency voltage appears at the circuit input. This transient high voltage is applied across the series-connected discharge tube 221. When the voltage peak exceeds the inherent DC breakdown voltage of the discharge tube 221, the insulating medium (such as gas) inside the discharge tube 221 is instantaneously ionized, rapidly transitioning from a high-resistance insulating state to a low-resistance conducting state. The conduction of the discharge tube 221 establishes a rapid path for the transient high voltage, allowing it to be applied to the conductors of the flexible circuit board 223 and directly transmitted to the end of the conductors, i.e., the discharge head 224.

[0062] At this time, the discharge head 224 acts as an exposed electrode, with its tip maintaining a precisely preset air gap distance from the first spacer 211. As the potential of the discharge head 224 rapidly rises to near instantaneous high voltage after the discharge tube 221 is turned on, the discharge head 224 generates an electric spark. This spark ionizes the air, igniting the air gap between the first spacer 211 and the discharge head 224, causing it to break down and discharge. The ions generated by the partial discharge further undergo an avalanche effect, creating a discharge path between the first spacer 211 and the second spacer 212.

[0063] Once the surge peak has passed and the line voltage drops, the arc current within the metal gap will be interrupted by the arc-extinguishing grid 300, and the metal gap will return to its insulating state. The connection between the discharge head 224 and the first gap plate 211 will also be open-circuited because the power frequency voltage is lower than the breakdown voltage of the discharge tube 221. The entire ignition circuit 22 will therefore automatically reset, returning to a high-resistance standby state, ready to respond to the next overvoltage event.

[0064] In this embodiment, the cooperation between the metal gap 21 and the ignition circuit 22 can actively trigger an arc to discharge energy when an overvoltage occurs, forming a discharge path. This applies the overvoltage to the SPD module 30, which then discharges the surge. After the surge voltage disappears, the powerful follow current interruption capability quickly cuts off the follow current, preventing the SPD module 30 from being damaged by the power frequency voltage in its conducting state and helping it quickly return to a high-resistance state. It also blocks the leakage current generated by the SPD module 30 under power frequency voltage, preventing degradation and extending its lifespan. Simultaneously, an independent protection actuator directly monitors and responds to the temperature of the metal gap 21, providing backup cut-off protection independent of the main discharge path for any abnormal overheating caused by any reason, thereby effectively preventing fires caused by thermal runaway.

[0065] Furthermore, this solution offers significant convenience and cost-effectiveness in maintenance. The standardized socket design on the base 10 allows the SPD module 30, a vulnerable component, to be quickly plugged in and replaced independently of the structurally complex backup protector, greatly reducing the cost and time of subsequent maintenance. Overall, this claim constructs a comprehensive protection system integrating active discharge, overheat protection, and modular maintenance, improving the overall safety, reliability, and service life of the surge protection system.

[0066] A further technical solution is that the protection actuator includes a temperature sensor 40 and an energy storage drive device 50. The temperature sensor 40 is disposed on the first gap 211, and the energy storage drive device 50 is mechanically coupled to the temperature sensor 40. When the temperature detected by the temperature sensor 40 reaches a preset threshold, the energy storage drive device 50 is triggered and cuts off the ignition circuit 22.

[0067] In specific implementation, the protection actuator includes a temperature sensor 40 and an energy storage drive device 50. The temperature sensor 40 is directly mounted on the first gap 211, or positioned adjacent to it in a manner that allows for accurate sensing of the temperature of the first gap 211, to ensure the directness and accuracy of its monitoring signal. The energy storage drive device 50 is mechanically coupled to the temperature sensor 40. Its working mechanism is as follows: when the temperature of the first gap 211, as monitored in real time by the temperature sensor 40, reaches a preset critical threshold, the temperature sensor 40 generates a mechanical trigger signal. This mechanical trigger signal acts on the energy storage drive device 50 coupled to it, causing the energy storage drive device 50 to be released from its energy storage standby state and trigger its action. The ultimate purpose of this action is to physically cut off the aforementioned ignition circuit 22, thereby terminating any possible continuous arcing or abnormal heating process.

[0068] In this embodiment, the protection actuator is concretized as a two-stage linkage system consisting of temperature sensor 40 sensing and mechanical drive execution, thereby achieving automation and high reliability of protection. By directly placing the temperature sensor 40 on the heat source, i.e., the first gap 211, it is possible to capture the temperature of critical parts instantly and accurately, avoiding the delay and error caused by indirect temperature measurement and ensuring the accuracy of the protection response. The mechanical coupling between the temperature sensor 40 and the energy storage drive device 50 means that the entire triggering and execution process does not rely on easily interfered electronic signals and complex circuits, but is based on direct physical and mechanical action, which has strong anti-interference ability and high action determinism.

[0069] A further technical solution is that the temperature sensor 40 is a bimetallic strip, which is connected to the first gap 211, and the bimetallic strip is provided with a hook 41; the energy storage drive device 50 includes a sliding insert 51 and an elastic element 52, the elastic element 52 abutting between the sliding insert 51 and the support; the sliding insert 51 is provided with a slot 511, wherein the hook 41 engages with the slot 511, and when the temperature detected by the bimetallic strip reaches a preset threshold, the bimetallic strip deforms to disengage the hook 41 from the slot 511, and the elastic element 52 drives the sliding insert 51 to insert between the contact piece 222 and the discharge tube 221 to cut off the ignition circuit 22.

[0070] In specific implementation, the temperature sensor 40 is a bimetallic strip, one end of which is fixedly connected to the first gap 211 to ensure that it can sensitively deform with the temperature change of the first gap 211. The bimetallic strip has a specific hook 41. The energy storage drive device 50 specifically includes a sliding insert 51 and an elastic element 52 (e.g., a spring) that provides driving force. One end of the elastic element 52 acts on the sliding insert 51, and the other end abuts against a support, such as the bottom shell 24 of the backup protection module 20, thereby placing the elastic element 52 in a compressed energy storage state. The sliding insert 51 has a groove 511 that cooperates with the hook 41 of the bimetallic strip. Under normal operating temperature, the hook 41 of the bimetallic strip remains engaged with the groove 511 of the sliding insert 51, thereby locking the sliding insert 51 and constraining the release of potential energy from the elastic element 52. When the bimetallic strip detects that the temperature reaches a preset threshold, its thermally induced deformation in a specific direction increases, causing the hook 41 to shift and disengage from the groove 511. Once released, the unconstrained elastic element 52 will quickly release its stored elastic potential energy, driving the sliding insert 51 to move along a preset path. The endpoint of the sliding insert 51's movement is when it is inserted into the connection between the contact piece 222 and the discharge tube 221, forcibly separating the two through physical insertion, thereby cutting off the current path of the ignition circuit 22.

[0071] This embodiment provides a simple, reliable, and low-cost mechanical temperature control triggering and execution scheme. A bimetallic strip is used as the temperature sensor 40, utilizing its inherent thermal bimetallic effect. Temperature changes are directly converted into mechanical displacement, eliminating the need for external power supplies and signal processing circuits, achieving completely passive temperature monitoring and triggering. The structure is simple and has a long lifespan. The potential energy of the elastic element 52 is stored through a mechanical interlock between the hook 41 and the slot 511, allowing the entire mechanism to remain stably in standby mode until the action threshold is reached, preventing malfunctions. When overheating occurs, the deformation of the bimetallic strip directly releases the mechanical interlock, with almost no delay between energy release and action execution, resulting in a rapid response. The sliding insert 51 directly inserts into the electrical connection point to physically cut off the circuit. This mechanical isolation is more thorough and reliable than electronic switches, effectively cooperating with the arc-extinguishing grid 300 to interrupt any potential power frequency follow current. This design integrates temperature sensing, energy storage, mechanical triggering, and circuit cutting into a compact mechanical linkage mechanism, ensuring the necessity and irreversibility of protection action under harsh conditions, greatly improving the ultimate reliability of backup protection.

[0072] A further technical solution is that the backup protection module 20 also includes an indicator 60, which is connected to the sliding insert 51. When the sliding insert 51 is inserted between the contact piece 222 and the discharge tube 221, it synchronously drives the indicator 60 to change its indication state.

[0073] In practice, the indicator 60 is connected to the sliding insert 51, creating a linkage between them. Specifically, when the sliding insert 51 is activated by temperature, i.e., driven by the elastic element 52 to insert between the contact piece 222 and the discharge tube 221 to cut off the ignition circuit 22, its movement synchronously causes a change in the position or state of the connected indicator 60. This change is designed to be a visible indication of the status change. For example, when a portion of the indicator 60 moves to a pre-set observation window on the housing of the backup protection module 20, the color displayed in the window changes from green (representing normal operation) to red (representing activation or malfunction), thus providing a clear and intuitive local visual alarm signal to on-site personnel.

[0074] This embodiment adds a local visual indication function for the device status, greatly improving the maintainability and on-site safety of the equipment. By mechanically linking the indicator 60 with the sliding insert 51 of the core protection action execution component, it ensures that the indicated status is strictly synchronized with the actual working status of the protection device and corresponds one-to-one, resulting in extremely high accuracy and reliability. When the backup protector performs a cut-off action due to overheating, the instantaneous change in the status of the indicator 60 provides operators and maintenance personnel with a clear and unambiguous local visual signal, enabling them to quickly locate the protection unit that has activated, without the need for complex testing using special tools or instruments. This not only facilitates daily inspections and troubleshooting, shortening maintenance time, but more importantly, it immediately alerts personnel after a fault occurs, preventing live operations or misjudgments of the system status without noticing that the protector has activated, thereby improving the maintenance safety and operational convenience of the entire power distribution system.

[0075] A further technical solution is that a remote signaling switch 70 is provided in the base 10. When the sliding insert 51 is inserted between the contact piece 222 and the discharge tube 221, the indicator 60 is driven to trigger the remote signaling switch 70 to change the electrical state.

[0076] In specific implementation, a remote signaling switch 70 is installed in the base 10. This remote signaling switch 70 is an electrical switching element whose state changes can be converted into remotely monitorable electrical signals. Its arrangement ensures that when the sliding contact 51 moves and causes the indicator 60 to change state, the indicator 60 simultaneously acts on the remote signaling switch 70. For example, when the indicator 60 moves to its final position, a protrusion on it presses against the contact of the remote signaling switch 70, causing a change in the electrical contact state of the switch, such as from normally open to closed or from normally closed to open. This state change can be transmitted to a remote monitoring system via a wire connected to the remote signaling switch 70, enabling remote alarm or status indication.

[0077] This embodiment adds remote electrical status monitoring capabilities to the local visual indication, realizing centralized monitoring and intelligent management of the protection device status. By directly linking the triggering of the remote signaling switch 70 with the core mechanical component (indicator 60) of the protection action, a high degree of consistency and real-time performance between the remote signal and the actual local status is ensured. Once the backup protector trips due to a fault, the remote monitoring center or building automation system can immediately receive the status change signal without the need for on-site inspection. This enables maintenance personnel to perform real-time, centralized status monitoring of surge protectors located in multiple locations, promptly identify the location of the fault, and facilitate rapid organization of maintenance and repair.

[0078] A further technical solution is that the backup protection module 20 also includes a manual operation device 80, which includes a handle 81 connected to the sliding insert 51. An operation window 231 is provided on the upper shell 23 of the backup protection module 20. The handle 81 extends to the outside of the shell through the operation window 231. The sliding insert 51 and the indicator 60 can be reset by manually operating the handle 81.

[0079] In specific implementation, a manual operation device 80 is added to the backup protection module 20, specifically including a handle 81 connected to the sliding insert 51. The upper shell 23 of the backup protection module 20 has a dedicated operation window 231. One end of the handle 81 is fixedly connected to the sliding insert 51 inside the module, while the other end extends through the operation window 231 to the outside of the shell for easy manual access and operation. When the backup protector activates due to a fault, the sliding insert 51, the indicator 60, and the remote signaling switch 70 are all in the triggered state. At this time, maintenance personnel can manually operate (e.g., toggle or push) the handle 81 from the outside. Since the handle 81 is directly connected to the sliding insert 51, manually operating the handle 81 will force the sliding insert 51 to move in the reverse direction from its activated position (i.e., the position between the contact piece 222 and the discharge tube 221) along its original path or a specific reset path, thus exiting the isolation state of the ignition circuit 22. The reset movement of the sliding insert 51 will cause the hook 41 of the bimetallic strip to re-engage into the slot 511 of the sliding insert 51, and simultaneously drive the indicator 60 to return to its original indicating state (e.g., the red window returns to green). It also releases the pressure on the remote signaling switch 70, restoring its electrical state to its initial state. Through this series of linkages, the entire backup protection module 20 can be manually restored to its normal standby state after the fault has been eliminated.

[0080] This embodiment achieves resettable and reusable backup protector, overturning the traditional "one-time use" model of fuse-type protection devices and bringing significant economic and environmental benefits. By providing an exposed handle 81 mechanically connected to the sliding plate 51, a direct, simple, and reliable manual reset method is provided. After a protection action occurs, once the front-end fault has been confirmed, maintenance personnel can manually operate the handle 81 on-site to reset the core actuator (sliding plate 51), status indicator (indicator 60), and signal output component (remote signaling switch 70) simultaneously, without replacing any internal components. This allows the backup protector to handle multiple fault events throughout its lifespan, greatly reducing spare parts inventory costs and replacement and maintenance costs.

[0081] A further technical solution is that the first spacer 211 is provided with a through hole, and an insulating frame 90 is embedded in the through hole. The discharge head 224 is inserted into the insulating frame 90 to extend into the through hole of the first spacer 211, thereby getting close to the first spacer 211. The thickness of the insulating frame 90 determines the distance between the discharge head 224 and the edge of the through hole of the first spacer 211.

[0082] In a specific implementation, a through hole is formed in the first spacer 211. A frame made of insulating material (such as plastic), namely the insulating frame 90, is embedded within this through hole. The discharge head 224, extending from the flexible circuit board 223, precisely passes through the central channel of the insulating frame 90 during installation. The distance between the discharge head 224 and the edge of the through hole in the first spacer 211 is determined by the thickness of the insulating frame 90. The insulating frame 90 serves multiple functions: firstly, it physically isolates the metal discharge head 224 from the metal first spacer 211 in areas other than the discharge point, ensuring reliable insulation between them and preventing unexpected short circuits; secondly, it precisely fixes the spatial position of the tip of the discharge head 224 relative to the edge of the first spacer 211, thereby determining and maintaining the precise air gap distance required for discharge; thirdly, it provides mechanical support for the discharge head 224, preventing displacement due to vibration or external forces, which would affect discharge performance.

[0083] This embodiment solves three key problems simultaneously—positioning accuracy, insulation safety, and mechanical stability—of the discharge head 224 through a simple insulating frame 90 structure, thereby ensuring high reliability and consistency in the operation of the ignition circuit 22. The insulating frame 90 acts as a physical isolation barrier between the discharge head 224 and the first spacer 211, fundamentally eliminating the possibility of leakage or short circuits in non-discharge areas due to installation errors, dust accumulation, or moisture, thus improving the product's electrical safety level. Secondly, it firmly holds the discharge head 224 in a preset position, ensuring a constant distance between the tip of the discharge head 224 and the edge of the through-hole in the first spacer 211. This distance directly determines the trigger voltage threshold of the ignition circuit 22. Precise positioning means stable trigger voltage, avoiding product performance discrepancies caused by component tolerances or assembly errors, and ensuring the consistency of the operating parameters of each protector. Finally, it provides additional mechanical reinforcement to the discharge head 224, enhancing the entire ignition circuit 22 module's resistance to mechanical vibration and impact, and improving the product's long-term reliability in harsh environments.

[0084] A further technical solution is that the bottom shell 24 of the backup protection module 20 is provided with a guide groove 241 to guide the movement direction of the sliding insert 51, and the sliding insert 51 is at least partially embedded in the guide groove 241.

[0085] In specific implementation, a guide groove 241 is specially provided on the bottom shell 24 of the backup protection module 20. This guide groove 241 is a groove or guide rail structure with a specific shape and path. The structure of the sliding insert 51 is designed to match the guide groove 241, with at least a portion (e.g., flanges on both sides or specific sliders) embedded within it. When the energy storage drive device 50 is triggered, and the elastic element 52 drives the sliding insert 51 to move, the portion embedded in the guide groove 241 will strictly follow the path and direction defined by the guide groove 241. The function of the guide groove 241 is to constrain the degree of freedom of movement of the sliding insert 51, ensuring that it can only move along a single, preset straight line or specific curved trajectory, thereby ensuring that the sliding insert 51 can accurately reach its predetermined action position, that is, precisely insert into the narrow gap between the contact piece 222 and the discharge tube 221.

[0086] This embodiment, by setting the guide groove 241, greatly improves the accuracy, reliability, and repeatability of the sliding insert 51's movement, which is a key guarantee for ensuring that the mechanical protection mechanism effectively performs its cutting-off function. The guide groove 241 forcibly constrains the movement path of the sliding insert 51, eliminating the possibility of it deviating, twisting, or getting stuck during movement. This ensures that in each triggering action, the sliding insert 51 can move with a completely consistent trajectory and direction, ultimately accurately inserting into the target position to achieve reliable isolation of the ignition circuit 22. Without the guide groove 241, the sliding insert 51 may experience unpredictable deviations under spring drive, resulting in ineffective circuit cutting or interference with other components, causing protection function failure or mechanism damage.

[0087] In some preferred embodiments, the ends of the two electrodes (i.e., the first gap 211 and the second gap 212) are gradually opening, resembling a ram's horn. This shape allows the arc, after being generated, to automatically elongate upwards along the electrode surface and extend towards the arc-extinguishing grid 300 within the cavity under the influence of electromagnetic force and hot airflow. The arc-extinguishing grid 300 is composed of a set of mutually insulated, parallel metal grids, which are typically positioned between the two electrodes or above the arc's path. When the arc is elongated into the arc-extinguishing grid 300 region, it is divided into a series of short arcs connected in series. Each short arc generates a voltage drop in its own cathode and anode regions, and the sum of the voltage drops of all short arcs is much greater than the voltage drop of the original single long arc. This is equivalent to connecting many high-resistance components in series along the arc path, thereby limiting the arc current. At the same time, the grids provide a large heat dissipation area, which can rapidly cool the arc plasma and promote arc extinction.

[0088] This embodiment, through the specific structure of a metal gap 21 with an arc-extinguishing grid 300, endows the backup protector with strong power frequency follow current interruption capability and self-extinguishing arc characteristics. This is the fundamental reason why it can safely interrupt continuous short-circuit current and prevent the escalation of accidents. The shape design of the horn electrode utilizes the characteristics of the electric arc itself, causing it to automatically elongate and move away from the root, creating favorable conditions for arc cooling and extinguishing. The arc-extinguishing grid 300 structure further mechanically divides the long arc into multiple short arcs, not only rapidly increasing the arc voltage through the near-electrode voltage drop effect to limit the current, but also greatly increasing the contact area between the arc and the cooling medium, accelerating the deionization process. The combination of these two features allows the metal gap 21 to quickly and reliably cut off the power frequency follow current formed by the continuous application of power frequency voltage due to system faults after discharging the impact surge current, relying on its structural advantages. This avoids serious secondary accidents such as electrode melting, insulation damage, or even fire and explosion caused by the continuous burning of the arc.

[0089] A further technical solution is that the upper shell 23 of the backup protection module 20 is provided with a contact window 232 and an insertion hole 233. One end of the contact piece 222 passes through the contact window 232 and abuts against the discharge tube 221, and the other end of the contact piece 222 passes through the insertion hole 233 and abuts against the second spacer piece 212.

[0090] In practice, the upper shell 23 of the backup protection module 20 is not completely sealed, but has two specific windows: a contact window 232 and an insertion hole 233. The contact piece 222 is a flexible conductive metal sheet. During module assembly, one end of the contact piece 222 (e.g., the end for contacting the electrode plane of the discharge tube 221) passes through the contact window 232 of the upper shell 23, extends into the module, and is tightly pressed against the corresponding electrode of the discharge tube 221 by its own elasticity. The other end of the contact piece 222 passes through the insertion hole 233 of the upper shell 23, extends towards the mounting position of the second spacer 212, and is elastically pressed or inserted into the pre-set mounting groove 200 or contact point on the second spacer 212. This design means that the contact piece 222 is installed and fixed externally through these two windows only after the upper shell 23 of the backup protection module 20 is closed with the base. The elasticity of the contact piece 222 ensures that the contact pressure between it and the discharge tube 221 and the second gap piece 212 is stable and reliable, unaffected by slight vibrations or thermal expansion and contraction, and maintains good electrical conductivity.

[0091] This embodiment provides a contact piece 222 mounting structure that facilitates assembly and ensures long-term contact reliability, thereby improving product manufacturing efficiency and electrical connection stability. By opening a contact window 232 and an insertion hole 233 in the upper shell 23, a "post-installation" method for the contact piece 222 is achieved. In the assembly process, all other components inside the module (such as spacers, circuit boards, discharge tubes 221, etc.) can be positioned and initially fixed on the base first, then the upper shell 23 is closed, and finally the contact piece 222 is installed from the outside through the reserved window. This assembly sequence avoids interference and difficulties that may be caused by operating multiple elastic components simultaneously in a confined space, simplifies the production process, and improves assembly efficiency and consistency. More importantly, the contact piece 222 relies on its own elastic deformation after passing through the window to provide contact pressure. This design ensures that the contact pressure originates from the inherent properties of the contact piece 222 material, rather than depending on factors that are difficult to precisely control, such as the screw tightening torque during assembly. Therefore, the contact resistance is more stable, and the risk of poor contact due to stress relaxation during long-term use is lower, ensuring the long-term reliability of the electrical performance of the ignition circuit 22.

[0092] Example 2

[0093] See Figure 9 and combined Figures 1-8 Embodiment 2 of the present invention proposes a backup protector for a surge protector. In Embodiment 2, the base 10 is a three-phase system base 10, and the base 10 integrates three backup protection modules 20 and one N-PE surge protector module 400. The base 10 is provided with sockets corresponding to the three SPD modules 30 respectively. In Embodiment 2, the connection method between the backup protection module 20 and the SPD module 30 is the same, and will not be described again here.

[0094] In practical implementation, the base 10 is designed as an integrated base 10 specifically for three-phase systems. Internally, it integrates three independent backup protection modules 20, which are electrically and structurally isolated from each other, corresponding to the protection requirements of the L1, L2, and L3 phase lines of the three-phase system, respectively. In addition, the base 10 also directly integrates (builds in) an N-PE surge protector module 400 to provide surge protection between the neutral line N and the protective earth line PE. Simultaneously, the base 10 is also provided with three independent sockets corresponding to the aforementioned three backup protection modules 20. Users can insert three independent LN-type SPD modules 30 into these three sockets respectively. Each SPD module 30 forms a series protection branch with its corresponding built-in backup protection module 20, collectively constituting three complete protection channels: L1-N, L2-N, and L3-N. N-PE protection is handled by the built-in module.

[0095] This embodiment provides a compact, neat, and easy-to-install complete surge protection solution for three-phase four-wire power supply systems through a highly integrated modular design. It integrates the backup protection function of the three phases with the N-PE protection function into a unified physical base 10, greatly saving installation space in distribution boxes or control cabinets, making wiring more organized and reducing wiring errors and space waste that may result from the scattered installation of multiple independent components. Users only need to connect the external three-phase power lines to the corresponding terminals of the base 10 and then insert the three standardized SPD modules 30 into the designated sockets to complete the connection of the entire protection circuit. The installation process is extremely simple, reducing the technical requirements for installers. This integrated design not only improves installation efficiency and reduces on-site work time but also facilitates later maintenance and management, as the status of all protection units (observable through the indicators 60 of each backup protection module 20) and wiring are centralized on a single device.

[0096] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0097] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0098] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0099] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0100] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0101] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0102] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Since these modifications and variations fall within the scope of the claims and their equivalents, this invention also intends to include these modifications and variations.

[0103] The above description describes specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A backup protector for a surge protector, characterized in that, include: The base is equipped with sockets for mounting SPD modules; The first terminal is disposed on the surface of the base; The second terminal is disposed on the surface of the base; A backup protection module is installed inside the base, including a metal gap and an ignition circuit; The metal gap includes a first gap plate, a second gap plate, and an arc-extinguishing grid, wherein the first gap plate is electrically connected to the first terminal; The ignition circuit includes a discharge tube, a contact piece, and a flexible circuit board. One end of the discharge tube is connected to the flexible circuit board. A wire connected to the discharge tube in the flexible circuit board extends to form a discharge head. The discharge head is close to the first gap piece. The other end of the discharge tube is electrically connected to the second gap piece through the contact piece. A protective actuator is used to cut off the ignition circuit when the temperature of the metal gap reaches a preset threshold. When the SPD module is inserted into the socket, the SPD module is connected in series between the metal gap and the second terminal.

2. The backup protector for the surge protector according to claim 1, characterized in that, The protection actuator includes a temperature sensor and an energy storage drive device. The temperature sensor is located on the first gap, and the energy storage drive device is mechanically coupled to the temperature sensor. When the temperature detected by the temperature sensor reaches a preset threshold, the energy storage drive device is triggered and cuts off the ignition circuit.

3. The backup protector for the surge protector according to claim 2, characterized in that, The temperature sensor is a bimetallic strip, which is connected to the first gap plate, and the bimetallic strip is provided with a hook; The energy storage drive device includes a sliding insert and an elastic element, wherein the elastic element abuts between the sliding insert and the support. The sliding insert is provided with a slot, wherein the hook engages with the slot. When the temperature detected by the bimetallic strip reaches a preset threshold, the bimetallic strip deforms, causing the hook to disengage from the slot. The elastic element drives the sliding insert to be inserted between the contact piece and the discharge tube to cut off the ignition circuit.

4. The backup protector for the surge protector according to claim 3, characterized in that, The backup protection module also includes an indicator connected to the sliding insert. When the sliding insert is inserted between the contact piece and the discharge tube, it synchronously drives the indicator to change its indication state.

5. The backup protector for the surge protector according to claim 4, characterized in that, The base is equipped with a remote signaling switch. When the sliding insert is inserted between the contact piece and the discharge tube, it synchronously drives the indicator to trigger the remote signaling switch to change the electrical state.

6. The backup protector for the surge protector according to claim 5, characterized in that, The backup protection module also includes a manual operation device, which includes a handle connected to the sliding insert. The upper shell of the backup protection module has an operation window, and the handle extends out of the outer shell through the operation window. The sliding insert and the indicator can be reset by manually operating the handle.

7. The backup protector for the surge protector according to claim 1, characterized in that, The first gap has a through hole, and an insulating frame is embedded in the through hole. The discharge head is inserted into the insulating frame to extend into the through hole of the first gap, thereby getting close to the first gap.

8. The backup protector for the surge protector according to claim 3, characterized in that, The bottom shell of the backup protection module is provided with a guide groove to guide the movement direction of the sliding insert, and the sliding insert is at least partially embedded in the guide groove.

9. The backup protector for the surge protector according to claim 1, characterized in that, The upper shell of the backup protection module has a contact window and an insertion hole. One end of the contact piece passes through the contact window and abuts against the discharge tube, and the other end of the contact piece passes through the insertion hole and abuts against the second spacer.

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