Intelligent excitation fuse

Abstract

The utility model relates to an intelligent excitation fuse, comprising: a first shell with a containing cavity for containing a gas generator; a second shell with a second gas channel communicating with the first gas channel; a third shell with a third gas channel communicating with the second gas channel; a fourth shell with a fourth gas channel communicating with the third gas channel; and a fifth shell below the fourth shell with a larger volume than the containing cavity of the fourth shell, and the containing cavity is in fluid communication with the exhaust hole and the fourth gas channel; wherein the first shell, the second shell, the third shell, the fourth shell and the fifth shell are tightly laminated by at least one fastener along the vertical axis direction. The utility model sets an optimized exhaust structure to avoid the shell under high pressure for a long time, avoid the shell cracking and the safety risk of explosion shell, and allow increasing the charge according to the requirement of breaking performance, thereby improving the safety performance of the product.

Description

Technical Field

[0001] This utility model relates to the field of switchgear technology, and in particular to an intelligent excitation fuse that can release high-pressure gas as a driving force and has an optimized exhaust structure. Background Technology

[0002] Fuses are commonly used short-circuit current protection devices in AC or DC circuits. Most protection devices in existing DC power systems use fuses, such as those manufactured by Eaton Bussmann, which work on the principle of electrothermal accumulation. When the current passing through the fuse generates sufficient heat, the internal metal conductor melts and arcs, thereby generating an arc voltage that reduces the short-circuit current.

[0003] Various new types of fuses are emerging, with the most widely used being the driven fuse. The primary function of the driven fuse is to protect against the blind spots of traditional fuses. For example, in the field of new energy vehicles, a driven fuse with breaking bars can be connected in series with a traditional fuse in the circuit. When a short circuit occurs and the traditional fuse fails to operate, the vehicle's BMS (Battery Management System) sends a signal to the driven fuse, causing it to trip and completing the protection. Because current flows through the current busbar during normal operation, its withstand capability is significantly improved compared to traditional fuses.

[0004] Currently, a relatively mature induction fuse product exists on the market, which mechanically disconnects the circuit. It includes a gas generator, a breaking grid, and a conductive busbar arranged sequentially. The gas generator and the breaking grid are housed in an upper housing, with the conductive busbar positioned between the upper and lower housings. A hollow section is provided in the upper housing; the gas generator is located at the top of the hollow section, and the breaking grid is located in the hollow section below the gas generator. A displacement space is provided on the lower housing for the breaking grid to displace after disconnecting the conductive busbar. The gas generator is an electronic ignition device that heats up upon receiving a trigger signal, causing a chemical reaction and releasing high-pressure gas as the driving force. For example, see the prior art patent document filed by the applicant of this application on November 26, 2024, with Chinese invention patent publication number CN119208107A and invention title "Intelligent Fuse".

[0005] However, due to limitations in product packaging size, internal pressure, and the characteristics of physical arc extinguishing, existing excitation fuse products, especially the injection molding strength of the housing, require a high charge quantity from the gas generator. This means that as the charge quantity increases, the upper limit of the existing housing structure's strength is insufficient, easily leading to housing cracking or even explosions. With the increasing demands for product reliability in the new energy vehicle industry, the reliability design requirements for DC high-voltage, high-current short-circuit protection products are becoming increasingly stringent. To improve the short-circuit breaking and short-time withstand capabilities of such products, a large charge quantity from the gas generator is often required to achieve reliable breaking. However, due to insufficient upper limit redundancy in the existing structure's strength, under the continuous impact of high-pressure gas, safety hazards such as housing cracking or even explosion can easily occur, failing to meet usage requirements. But if the charge quantity is reduced to ensure product safety and reliability, the excitation fuse product suffers from problems such as low short-circuit breaking capacity, small time constant, insufficient breaking speed, and difficulty in ensuring reliable breaking of the copper busbar.

[0006] Therefore, there is a technical need in this field to provide an intelligent excitation fuse that can simultaneously solve all the above-mentioned shortcomings, improve breaking capacity, has a simple structure, and high reliability. Utility Model Content

[0007] The present invention aims to provide an intelligent excitation fuse that can at least solve some of the above-mentioned problems.

[0008] According to one aspect of the present invention, an intelligent excitation fuse is provided, comprising: a first housing made of an electrically insulating material and having a first gas channel, wherein a cavity is provided for accommodating a gas generator; a second housing located below the first housing and integrally formed with at least one conductive bar, wherein a portion therein has an annular bushing extending toward the first housing, wherein the bushing surrounds a cavity for accommodating a breaking grid, wherein the second housing forms a second gas channel communicating with the first gas channel; and a third housing located below and mating with the second housing, wherein a portion therein has a through hole for serving as a downward channel for the breaking grid, wherein the third housing... The first housing has a third gas channel communicating with the second gas channel; a fourth housing located below the third housing, wherein the fourth housing has a receiving cavity in the middle containing an arc-extinguishing metal mesh and at least one exhaust hole at the bottom of the receiving cavity, wherein the fourth housing forms a fourth gas channel communicating with the third gas channel; and a fifth housing located below the fourth housing, which has a placement cavity with a volume larger than the fourth housing and the placement cavity is in fluid communication with the exhaust hole and the fourth gas channel; wherein the first housing, the second housing, the third housing, the fourth housing and the fifth housing are tightly laminated together by at least one fastener passing through in the vertical axis direction.

[0009] Compared with existing technologies, the intelligent excitation fuse according to this invention features an optimized venting structure. This effectively reduces the accompanying high-pressure gas pressure within the housing to a safe level instantly by passing it through the first to fourth gas channels and the pressure-stabilizing chamber located in the fifth housing immediately after the breaking grid breaks the conductive busbar. The optimized venting structure prevents the housing from being under high pressure differentials for extended periods, avoiding the safety risk of housing cracking and bursting, and allows for increased charge volume to meet breaking performance requirements, thereby improving product safety. Furthermore, since the first to fourth gas channels and the pressure-stabilizing chamber in the fifth housing can be injection molded, no additional components are added, thus reducing production costs.

[0010] As a preferred aspect, the first housing further includes a one-way valve located at the upper end of the first gas passage, wherein the one-way valve is designed to control the fluid communication between the first gas passage and the external atmospheric environment.

[0011] As a preferred aspect, it also includes a seal sandwiched between the first housing and the second housing, the second housing and the third housing, and the third housing and the fourth housing.

[0012] As a preferred aspect, the arc-extinguishing metal mesh has a generally rectangular cross-section and a recess in the central portion that is substantially the same as the cross-section of the breaking grid plate, serving as a downward channel for the breaking grid plate, so as to allow the downward breaking grid plate to be inserted into the recess.

[0013] As a preferred aspect, the system further includes a filter element sandwiched between the arc-extinguishing metal mesh and the bottom of the receiving cavity, wherein the filter elements are arranged in pairs about the vertical axis.

[0014] In a preferred aspect, the breaking grid includes a grid body that is axially symmetric with respect to a vertical axis and at least one breaking blade disposed therein, wherein the breaking blade has: an inner first blade surface; an outer second blade surface opposite to the first blade surface; a breaking cutting edge located between the two; and a breaking tip located at the lowermost end of the breaking cutting edge at a central position.

[0015] As a preferred aspect, the cutting edge is designed to extend obliquely downwards towards both sides of the blade body from the lowest cutting tip, wherein the opening angle or blade face angle through which the cutting edge extends is in the range of 210 degrees to 235 degrees.

[0016] As a preferred aspect, the device includes a pair of cutting blades, wherein the cutting edges of the cutting blades are arranged at an angle such that the opening angle formed by these cutting edges is in the range of 135 degrees to 165 degrees.

[0017] As a preferred aspect, the cleaving grid plate also has a cylinder at the end opposite to the cleaving blade for at least partially surrounding the gas generator.

[0018] As a preferred aspect, the second housing and / or the third housing are further provided with a clearance groove that corresponds to the break notch of the conductive busbar, so as to allow the part of the conductive busbar to be forced into the clearance groove after it is broken.

[0019] Other features and advantages of this invention will partly be apparent to those skilled in the art upon reading this application, and partly will be described below in conjunction with the accompanying drawings in the detailed description. Attached Figure Description

[0020] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings, wherein:

[0021] Figure 1 This is a front view of the first embodiment of the intelligent excitation fuse according to the present invention;

[0022] Figure 2 It is based on Figure 1 Top view of the intelligent excitation fuse in the image;

[0023] Figure 3 It is based on Figure 1 Cross-sectional view of the intelligent excitation fuse in the diagram;

[0024] Figure 4 This is an exploded view of the intelligent excitation fuse according to the present invention, wherein its various components are disassembled to show more internal details;

[0025] Figure 5 This is another cross-sectional view of the intelligent excitation fuse according to the present invention, wherein the breaking device is in the initial state;

[0026] Figure 6 This is another cross-sectional view of the intelligent excitation fuse according to the present invention, wherein the breaking device is in the working state;

[0027] Figure 7 yes Figure 6 A partially enlarged cross-sectional view of the intelligent excitation fuse outlined by A in the image;

[0028] Figure 8 It shows Figure 6 A schematic diagram of the flow of arc-extinguishing gas in a medium-sized intelligent excitation fuse when the breaking device is in operation;

[0029] Figure 9 A three-dimensional cross-sectional view is shown. Figure 6A schematic diagram of the flow of arc-extinguishing gas in a medium-sized intelligent excitation fuse when the breaking device is in operation;

[0030] Figure 10 Shown in a three-dimensional bottom view Figure 6 Schematic diagram of the arc-extinguishing chamber housing of a medium-sized intelligent excitation fuse;

[0031] Figure 11 Shown in 3D Figure 6 A schematic diagram of the opening grid of a medium-sized intelligent excitation fuse;

[0032] Figure 12 Shown in side view Figure 6 A schematic diagram of the opening grid of a medium-sized intelligent excitation fuse;

[0033] Figure 13 A side view from another perspective shows Figure 6 A schematic diagram of the opening grid of a medium-sized intelligent excitation fuse;

[0034] Figure 14 Shown from below Figure 6 A schematic diagram of the opening grid of a medium-sized intelligent excitation fuse;

[0035] Figure 15 This is a front view of the second embodiment of the intelligent excitation fuse according to the present invention;

[0036] Figure 16 It is based on Figure 15 Cross-sectional view of the intelligent excitation fuse in the diagram;

[0037] Figure 17 It is based on Figure 15 Top view of the intelligent excitation fuse in the image;

[0038] Figure 18 This is a front view of a second embodiment of the intelligent excitation fuse according to the present invention, wherein the intelligent excitation fuse is in a depressurized state;

[0039] Figure 19 This is a cross-sectional view of a second embodiment of the intelligent excitation fuse according to the present invention, showing a schematic diagram of the flow of arc-extinguishing gas;

[0040] Figure 20 It is based on Figure 18 A top view of a smart excitation fuse.

[0041] Explanation of reference numerals in the attached figures:

[0042] 100 - Intelligent excitation fuse; 101 - First housing; 101A - Fastener;

[0043] 101B - First gas passage; 101C - Check valve;

[0044] 102 - Second housing; 102A - Conductor bus; A - Break;

[0045] 102B - Second gas passage; 102C - Bushing; 102D - Seal; 102E - Clearance groove;

[0046] 103-Third housing; 103A-Seal; 103B-Third gas passage; 104-Fourth housing;

[0047] 104A - Exhaust port; 104B - Fourth gas passage; 104C - Seal; 105 - Fifth housing;

[0048] 105A - Drainage cavity; 201 - Signal lead; 201A - Gas generator; 202 - Interruption grid;

[0049] 202A - Seal; 202B - Grid body; 202C - Cutting tip; 202D - Cutting edge;

[0050] 202E - Cylinder body; 203 - Metal sleeve; 204 - Arc-extinguishing metal mesh; 205 - Filter element;

[0051] a-blade angle; b-opening angle; A1-vertical axis; Detailed Implementation

[0052] The schematic scheme of the intelligent excitation fuse disclosed in this utility model is now described in detail with reference to the accompanying drawings. Although the drawings are provided to illustrate some embodiments of this utility model, the drawings are not necessarily drawn to the dimensions of the specific embodiments, and certain features may be enlarged, removed, or partially cut to better illustrate and explain the disclosure of this utility model. Some components in the drawings may be repositioned according to actual needs without affecting the technical effect. The phrase "in the drawings" or similar terms appearing in the specification do not necessarily refer to all drawings or examples.

[0053] Certain directional terms used in the description of the accompanying drawings below, such as “inner,” “outer,” “above,” “below,” and other directional terms, will be understood to have their normal meaning and refer to those directions as normally viewed in the accompanying drawings. Unless otherwise specified, the directional terms used in this specification are generally in accordance with the conventional directions understood by those skilled in the art.

[0054] The terms “first,” “first,” “second,” “second,” and similar terms used in this utility model do not indicate any order, quantity, or importance, but are used to distinguish one component from other components.

[0055] The terms "joining", "connection" and similar terms used in this utility model include both indirect connection of two components with the aid of an intermediate layer such as an adhesive or welding agent or an intermediate component such as a connector or transition piece, and direct connection of two components without the aid of any intermediate layer such as an adhesive or welding agent or an intermediate component such as a connector or transition piece.

[0056] First embodiment of intelligent excitation fuse

[0057] Figures 1 to 14 A first embodiment of the intelligent excitation fuse 100 of this invention, its breaking device, and a control circuit for implementing internal and external triggering are illustrated by way of example. In this example, the intelligent excitation fuse 100 incorporates a breaking device to disconnect each phase circuit by forming an opening when a fault occurs in the protected circuit, thereby significantly improving the reliability of the intelligent excitation fuse 100. Preferably, the intelligent excitation fuse 100 and its breaking device of this invention are suitable for industrial applications, including photovoltaic devices, and therefore, the intelligent excitation fuse 100 of this invention needs to meet the electrical performance and technical requirements of the aforementioned industrial applications, including response time, breaking current, and arc suppression performance.

[0058] like Figures 1 to 4 As shown, the intelligent excitation fuse 100 according to this utility model may include an insulating housing with a layered structure and, preferably, a single breaking device. Specifically, the interior of the insulating housing has a mounting cavity for arranging the breaking device to allow the breaking device located therein to move up and down along the vertical axis A1, and the insulating housing may include, for example, a first housing 101, a second housing 102, a third housing 103, a fourth housing 104, and a fifth housing 105, which may be injection molded or molded from an electrically insulating material (e.g., PA66, PPS, etc.) and are stacked sequentially from top to bottom, with the uppermost first housing 101, the second housing 102, the third housing 103, the fourth housing 104, and the lowermost fifth housing 105.

[0059] First shell

[0060] exist Figure 3As shown, the uppermost first housing 101 can be a semi-enclosed cavity structure with a generally closed upper end (only leaving a lead-out hole for the signal lead 201 to be exposed) and an open lower end. The first housing 101 is designed as, for example, a cylindrical cavity in the middle, injection-molded or molded from an electrically insulating material (e.g., PA66, PPS, etc.), and a first gas channel 101B arranged annularly between the outer peripheral wall of the cylindrical cavity and the outer wall of the first housing 101. This cylindrical cavity is designed to have a receiving cavity communicating with the signal lead 201 for accommodating a gas generator 201A, wherein the gas generator 201A is designed to receive gas from a control circuit board (…). Figure 3 (not shown in the diagram) and signal fuse ( Figure 3 The control circuit (not shown in the figure) and signal lead 201, along with a trigger signal (preferably including internal and / or external trigger signals), ignites high-pressure gas, thereby pushing the switching grid 202 located below it to move downwards at high speed. As an example, the gas generator 201A has a pair of electrodes that receive trigger signals from the control circuit, wherein the gas generator 201A can be an ignition tube or an MGG gas generator. When a current signal is transmitted to the gas generator 201A through the pair of electrodes, the propellant inside the gas generator 201A is ignited, generating a large amount of high-pressure gas that fills the internal chamber of the second housing 102, pushing the switching grid 202 located below the gas generator 201A to move rapidly.

[0061] Preferably, such as Figure 3 As shown, to prevent the high-pressure gas accumulated in the cavity after the gas generator 201A is ignited from exceeding the material limit of the first housing 101 and thus causing cracking or explosion, a metal sleeve 203, for example made of stainless steel, is preferably embedded in the cylindrical cavity of the first housing 101. This significantly enhances the gas pressure that the cylindrical cavity can withstand. Furthermore, since the outer periphery of the cylindrical cavity is provided with a first gas channel 101B, this ensures that the insulation safety risk caused by embedding the conductive metal sleeve 203 in the first housing 101 is controllable.

[0062] Second shell

[0063] like Figure 3 and 4As shown, a second housing 102 is provided directly below the first housing 101 and is shaped to mate with it. The second housing 102 is designed as a plate-like structure with open upper and lower ends. In the middle of the plate-like second housing 102, there is a ring-shaped bushing 102C extending towards the cylindrical cavity of the first housing 101. A sealing element 102D for achieving gas sealing is provided at the lower end of the bushing 102C. As a result, when the cylindrical cavity in the middle of the first housing 101 mates with the bushing 102C of the second housing 102, the upper end of the bushing 102C abuts against the inner wall of the cylindrical cavity, and the lower end of the cylindrical cavity of the first housing 101 abuts against the surface of the second housing 102. The sealing element 102D is securely engaged between the lower end of the cylindrical cavity and the surface of the second housing 102, which essentially prevents gas leakage between them.

[0064] At the same time, such as Figure 3 and 4 As shown, the second housing 102 has a through-hole gas channel 102B located at the position of the first gas channel 101B in the first housing 101, preferably as shown in the figure. Figure 4 As shown, the second gas passage 102B is designed as a circular hole along the opposite ends of the second housing 102, so that the second gas passage 102B in the second housing 102 and the first gas passage 101B in the first housing 101 are always in fluid communication when the first and second housings are mated together.

[0065] Furthermore, a horizontally arranged conductive bar 102A is integrally formed in the second housing 102 of the plate-like structure by injection molding or molding, wherein both ends of the conductive bar 102A can extend from the second housing 102 to connect to each phase circuit. For example... Figure 3 and 4 As shown, a breakable grid plate 202 is provided in the cavity enclosed by the bushing 102C of the second housing 102, wherein the breakable grid plate 202 is preferably sealed by means of a sealing member 202A located at its upper end and the bushing 102C.

[0066] Opening grid plate

[0067] exist Figures 11 to 14 The diagram best illustrates a breaking grid 202 according to the present invention, wherein the breaking grid 202 may include, for example, a grid body 202B that is axisymmetric about a vertical axis A1, formed by injection molding or molding of an electrically insulating material (e.g., PA66, PPS, etc.), and preferably two breaking blades disposed therein. Figure 14As best shown, the breaking blade comprises two blades arranged side by side, wherein these breaking blades extend from the grid body 202B of the breaking grid 202 toward corresponding first and second breaks (framed by line A) in the conductive bus 102A. Figure 3 As shown, before the gas generator is triggered by an external signal, the ends of the breaking blades in the breaking grid 200 are located inside the corresponding first and second breaks.

[0068] like Figure 12 The illustration shows an exemplary cutting blade, preferably comprising a blade body made of alumina ceramic material. In the illustrated embodiment, the blade body is entirely made of alumina ceramic material. The cutting blade has an inner first blade body surface, an outer second blade body surface opposite to the first blade body surface, a cutting edge 202D located between the two, and a cutting tip 202C located at the lowermost end of the cutting edge 202D at its central position. The blade thickness, defined by the distance between the first and second blade body surfaces, is 2 mm to 5 mm. Here, the cutting edge 202D is designed to extend obliquely downwards towards both sides of the blade body from the lowermost cutting tip 202C, wherein the opening angle or cutting edge angle α through which the cutting edge 202D extends is preferably in the range of 210 degrees to 235 degrees.

[0069] Furthermore, such as Figure 13 As clearly shown, the cutting edges 202D of the cutting blades of the cutting grid 202 according to this invention are not horizontally arranged, but are designed to be higher on the outer side of the second blade surface and lower on the inner side of the first blade surface, that is, the cutting edges 202D are inclined relative to the horizontal direction. Here, the cutting edges 202D of the paired cutting blades are arranged obliquely in such a way that the opening angle b between their cutting edges 202D and each other is preferably in the range of 135 degrees to 165 degrees.

[0070] The inventors of this invention discovered that by designing the cutting edge 202D of the cutting blade in the cutting grid 202 of this invention to have an opening angle or blade face angle α in the range of 210 degrees to 235 degrees and an opening angle b in the range of 135 degrees to 165 degrees, the cutting tip 202C defined by this can be designed to be sharper than in the prior art. This facilitates concentrating the downward pressure on the cutting tip 202C at the moment of cutting the first and second breaks of the conductive busbar 102A, as described below. As a result, the maximum instantaneous pressure can be achieved when the cutting tip 202C is pressed down, thereby first cutting the conductive busbar 102A to create a tear, and then breaking it completely with the help of the cutting edge 202D. This cutting blade design makes it easier to cut the conductive busbar and achieves a faster cutting speed compared to the non-sharp design in the prior art.

[0071] More preferably, such as Figure 4 and 12 As shown, the breaking grid plate 202 of this utility model also has a cylinder 202E for surrounding the gas generator 201A at the end opposite to the breaking blade 202D. Figure 4 As best shown, the cylinder 202E is designed as a hollow annular structure. When the breaking grid 202 is used in the actuated fuse 100, the open end of the cylinder 202E is positioned towards the high-pressure gas release end of the gas generator 201A. The height of the cylinder 202E is determined by the relationship between the high-pressure gas release end 21 of the gas generator 201A of the actuated fuse and the cylinder 202E. Figure 3 and 5 As shown, the high-pressure gas release end of the gas generator 201A is almost entirely located in the cylinder 202E. The cylinder 202E contacts the gas generator 201A, forming a cylinder 202E that almost completely encloses the high-pressure gas release end of the electronic igniter.

[0072] The result is that, in such Figure 6 As shown, since the high-pressure gas released by the gas generator 201A acts entirely on the end face of the cylinder 202E, the instantaneous force exerted by the high-pressure gas on the breaking grid 202 becomes greater, increasing the initial kinetic energy of the breaking grid 202. Simultaneously, due to the presence of the cylinder 202E, when the high-pressure gas released by the gas generator 201A first impacts the cylinder 202E, a portion of the impact energy is absorbed by the cylinder 202E, which also provides some protection for the first housing 101 of the excitation fuse 100. At the same time, this design maximizes space utilization, thereby achieving a compact excitation fuse.

[0073] Furthermore, in Figure 3 and 7The diagram illustrates the mating relationship between the aforementioned breaking grid 202 and the conductive bus 102A. Specifically, the conductive bus 102A has two breaking notches with a width substantially the same as the breaking blades of the breaking grid 202. Figure 3 As shown, before the gas generator 201A is triggered, the end of the cutting blade of the breaking grid 202 is located inside the corresponding breaking notch. Preferably, corresponding to the cutting tip 202C of the cutting blade, a downward-opening stress concentration groove is provided at the centerline of the lower surface of the breaking notch of the conductive bus 102A, wherein the stress concentration groove and the cutting tip 202C of the cutting grid 202 are arranged opposite to each other. Through the cooperation of the cutting tip 202C of the cutting blade and the emergency concentration groove, stress concentration is easily generated at the centerline of the conductive bus 102A, and the cutting blade of the breaking grid 202 can more easily cut the conductive bus 102A from the middle position. Exemplarily, the thickness of the cutting blade and the width of the plurality of breaking notches can be 2 mm to 5 mm, and the thickness of the conductive bus 102A at the plurality of breaking notches is preferably, for example, 0.5 mm to 1 mm.

[0074] It should also be pointed out that, despite Figure 3 and 7 The diagram shows a breaking grid 202 with paired breaking blades for performing a breaking operation on a device with a breaking notch (referred to as a double-blade direct-opening type). Alternatively, it is also feasible to design a breaking grid 202 with multiple blades having two or more insulating blades (referred to as a multi-blade direct-opening type), and these variations are all covered within the scope of protection intended for this application.

[0075] Next Figure 7 More details of the interruption operation are shown, including a clearance groove 102E provided at the upper part of the downward channel of the interruption grid 202 along the vertical axis A1, which corresponds to the interruption notch of the conductor bus 102A. As a result, after interruption, the conductor bus is pushed into the clearance groove 102E by the interruption blade of the interruption grid 202 entering the downward channel, thus not hindering the movement of the interruption blade, allowing the interruption blade to continue to move downward, avoiding jamming that would lead to poor arc extinguishing effect and thus danger. Here, the clearance groove 102E can also be formed at least partially within the second housing 102 and / or the third housing 103 by injection molding or molding.

[0076] Third shell

[0077] like Figure 3 and 4As shown, a third housing 103, whose outer contour is substantially the same, is provided directly below the second housing 102. This third housing 103 is also designed as a plate-like structure with open upper and lower ends. In the middle of the plate-like third housing 103, there is a through hole through which the vertical axis A1 passes, serving as a downward channel for the opening grid plate 202. A sealing element 103A for achieving gas sealing is arranged around the outer periphery of this centrally located through hole. As a result, when the second housing 102 and the third housing 103 are laminated together, the sealing element 103A is firmly clamped between the lower surface of the second housing 102 and the upper surface of the third housing 102, which essentially prevents gas leakage between them.

[0078] At the same time, such as Figure 3 and 4 As shown, a third gas channel 103B is provided in the third housing 103 at a position corresponding to the second gas channel 102B of the second housing 102, preferably as shown below. Figure 4 As shown, the third gas passage 103B is designed as an elongated hole along the opposite ends of the third housing 103, so that the third gas passage 103B in the third housing 103 and the second gas passage 102B in the second housing 102 are always in fluid communication when the third and second housings are connected.

[0079] Fourth shell

[0080] like Figure 3-4 As shown in Figure 10, a fourth housing 104 with a substantially uniform cross-sectional profile is provided directly below the third housing 103. This fourth housing 104 is designed as a cup-shaped structure, open at the top and substantially closed at the bottom. Within the center of the cup-shaped fourth housing 104 is a cavity through which a vertical axis A1 passes, housing internal functional components such as the arc-extinguishing metal mesh 204 and the filter element 205, described in detail below. Furthermore, a sealing element 104C for achieving gas sealing is arranged around the outer periphery of this cavity. As a result, when the third housing 103 and the fourth housing 104 are laminated together, the sealing element 104C is securely clamped between the lower surface of the third housing 103 and the upper surface of the fourth housing 104, effectively preventing gas leakage between them.

[0081] At the same time, such as Figure 3 and 4 As shown, a fourth gas channel 104B is provided in the fourth housing 104 at a position corresponding to the third gas channel 103B of the third housing 103, preferably as shown below. Figure 4As shown, the fourth gas passage 104B is designed as an elongated hole along the opposite ends of the fourth housing 104, so that the fourth gas passage 104B in the fourth housing 104 and the third gas passage 103B in the third housing 103 are always in fluid communication when the fourth and third housings are connected.

[0082] Best in Figure 10 As shown, since the fourth housing 104 is designed as a cup-shaped structure with a substantially closed lower end, multiple elongated vent holes 104A are provided at the bottom of the housing 104 to transfer the arc-extinguishing gas formed in the containment cavity to the outside and fluidly communicate with the fourth gas channel 104B. The number and opening area of ​​these vent holes 104A depend on the generation rate of the arc-extinguishing gas in the containment cavity. Generally speaking, it is beneficial to have more long vent holes 104A when the breaking current and breaking speed of the smart fuse are large, and vice versa. At the same time, to ensure that the gas in the containment cavity is uniformly transferred to the outside of the cavity, it is beneficial to distribute these vent holes 104A symmetrically about the vertical axis A1.

[0083] Preferably, a partition portion aligned with the vertical axis A1 is integrally formed at the center of the receiving cavity of the fourth housing 104. Subsequently, the arc-extinguishing metal mesh 204 and the filter element 205, arranged in pairs around the partition portion, can be stacked and placed into the receiving cavity. Figure 10 As shown, the arc-extinguishing metal mesh 204 is designed with a generally rectangular cross-section and a recess in the central portion that is substantially the same as the cross-section of the breaking grid 202. As a result, these recesses in the arc-extinguishing metal mesh 204 serve as part of the downward channel of the breaking grid 202, ensuring that a significant portion of the breaking blades of the breaking grid 202 are embedded within the arc-extinguishing metal mesh 204 when it reaches its final position. The inventors of this invention have found that this design achieves better arc-extinguishing performance and higher insulation resistance. Preferably, the arc-extinguishing metal mesh 204 is made of stainless steel. Furthermore, to prevent carbides generated by arc erosion of the housing or other components from clogging the vent 104A, a filter element 205, preferably made of cotton, is arranged directly below the arc-extinguishing metal mesh 204.

[0084] Fifth shell

[0085] like Figure 3-4As shown in Figure 10, a fifth housing 105 with a substantially uniform cross-sectional profile is located directly below the fourth housing 104. This fifth housing 105 is designed as a cup-shaped structure, open at the top and substantially closed at the bottom. The cup-shaped fifth housing 105 encloses a cavity for housing the fourth housing 104. The volume of this cavity is designed to be larger than the volume of the fourth housing 104 within it, thereby creating a pressure-stabilized space between them for the gas escaping from the exhaust port 104A of the fourth housing 104. Simultaneously, since the upper end of the fifth housing 105 is open, the pressure-stabilized gas can freely communicate with the fourth channel 104B located above it.

[0086] like Figure 4 As clearly shown, the first housing 101, second housing 102, third housing 103, fourth housing 104, and fifth housing 105 all have fastening holes for fasteners to pass through so as to laminate them together. These fastening holes are aligned with each other along the vertical axis A1. Figure 4 As shown, multiple fasteners 101A, such as long bolts, are sequentially passed through fastening holes in the first housing 101, the second housing 102, the third housing 103, the fourth housing 104, and the fifth housing 105, thereby reliably laminating and bonding these housings together.

[0087] As a result, this invention incorporates an optimized venting structure in the excitation fuse, which effectively reduces the accompanying high-pressure gas pressure to a safe level instantly through the first to fourth gas channels and the pressure-stabilizing chamber located in the fifth housing 105 immediately after the breaking grid 202 breaks the conductive busbar 102A. By implementing the optimized venting structure, the housing is prevented from being under high pressure differentials for extended periods, avoiding the safety risk of housing cracking and bursting, and allowing for increased charge quantity based on breaking performance requirements, thereby improving product safety performance.

[0088] Furthermore, since the first to fourth gas channels and the pressure-stabilizing chamber located in the fifth housing 105 can all be injection molded, no additional parts are added, and therefore, production costs are not increased.

[0089] Working principle of intelligent excitation fuse

[0090] Under normal operating conditions, current flows through the two opposite ends of the conductor bus 102A and the signal fuse connected in parallel with it. Under normal operating conditions, current flows through the conductor bus 102A, and since the resistance of the signal fuse is much greater than the resistance of the conductor bus 102A, the current flowing through the signal fuse is negligible. At this time, the intelligent excitation fuse 100 is in a state of... Figure 5 The initial state is shown in the figure.

[0091] In the event of overload, short circuit, or abnormal conditions, the system detects a short-circuit current or a trigger signal, which is transmitted to the gas generator 201A via signal lead 201. As a result, a downward gas pressure is generated by triggering and igniting a pyrotechnic device via its pin. In response to the gas pressure applied to the upper surface of the interrupting grid 202, the interrupting grid 202 moves downward along the vertical axis A1 within the cavity enclosed by the bushing 102C until it interrupts the conductive busbar 102A located in the second housing 102. Figure 6 As indicated in section A. During this period, such as Figure 7 As shown, since there is a clearance groove 102E below the break notch of the conductive busbar 102A, the material of the cut or broken conductive busbar 102A will not hinder the continued downward movement of the break gate 202, but will be forced into the clearance groove 102E.

[0092] As the breaking grid 202 continues to descend, the arc generated at the breaking notch of the conductive bus 102A will descend along with the breaking grid 202 and subsequently enter the recess of the arc-extinguishing metal mesh 204 located in the fourth housing 104. The arc can then be rapidly extinguished by the cooling effect of the arc-extinguishing metal mesh 204.

[0093] During this process, a large amount of ionized gas will be generated within the fourth housing 104 in a short period of time. Especially when the gas expands due to heat, it will exert tremendous pressure on the entire cavity, thus placing particular impact pressure on the fourth housing 104. This gas pressure within the fourth housing 104 will cause the following adverse consequences: 1. It will lead to turbulence, causing the electric arc to erratically and failing to extinguish quickly, potentially resulting in product explosion; 2. The gas pressure will directly cause the housing to rupture; 3. It will cause the interrupted grid plate 202 to rebound, failing to engage properly, resulting in secondary reignition of the electric arc under high pressure, and product explosion.

[0094] As described above, the fourth housing 104 of this invention has an open bottom design and a filter element 205 is designed at the bottom of the arc-extinguishing metal mesh 204 located therein. As a result, gas with a certain pressure, after passing through the exhaust port 104A of the fourth housing 104, continues to enter the placement cavity within the fifth housing 105. As described above, because the space of the placement cavity in the fifth housing 105 is sufficiently large, the average gas pressure within the cavity can be effectively reduced, which is equivalent to directly releasing the high pressure in the receiving cavity of the fourth housing 104. After the gas is stabilized in the fifth housing 105, as... Figure 8 and 9 As shown, these gases will gradually flow upward and rise through the fourth gas channel 104B, the third gas channel 103B, the second gas channel 102B, and the first gas channel 101B.

[0095] Second embodiment of intelligent excitation fuse

[0096] Figures 15 to 20 A second embodiment of the intelligent excitation fuse 100 of this utility model is shown by way of example. This embodiment is similar to... Figures 1 to 14 The main difference in the illustrated embodiment is that a one-way valve 101C for controlling communication with the external atmospheric environment is added to the end of the first gas passage 101B in the first housing 101. Here, the one-way valve 101C is designed, for example, as follows: Figure 16 As shown, the first gas passage 101B is kept sealed during the transport or assembly of the intelligent excitation fuse 100 to prevent foreign objects or dust from falling into the first gas passage 101B and causing blockage.

[0097] After the intelligent excitation fuse 100 is connected to the electrical circuit to be protected, the operator can manually, for example, turn the one-way valve 101C from... Figure 16 The state transition shown is to Figure 18 The open state shown indicates that the first gas passage 101B is connected to the external atmospheric environment. As a result, as... Figure 19 As shown, the high-pressure gas generated in the fourth housing 104 passes through the exhaust port 104A, the pressure stabilizing chamber of the fifth housing 105, the fourth gas passage 104B of the fourth housing 104, the third gas passage 103B of the third housing 103, the second gas passage 102B of the second housing 104, and finally is discharged into the outside atmosphere through the first gas passage 101B of the first housing 101.

[0098] The addition of a one-way valve 101C reduces the gas pressure accumulated in the intelligent excitation fuse 100, thereby improving the reliability of the product throughout its entire life cycle.

[0099] It should be understood that although this specification describes various embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0100] The above description is merely an illustrative embodiment of this utility model and is not intended to limit the scope of this utility model. Any equivalent changes, modifications, and combinations made by those skilled in the art without departing from the concept and principles of this utility model should fall within the protection scope of this utility model.

Claims

1. An intelligent excitation fuse (100), characterized in that, include: A first housing made of electrically insulating material, having a first gas passage, and having a accommodating cavity for housing a gas generator; A second housing located below the first housing, integrally formed with at least one conductive bar, has a centrally located annular bushing extending toward the first housing, wherein the bushing encloses a cavity for accommodating the open-circuit grid, and wherein the second housing forms a second gas channel communicating with the first gas channel. The third housing located below and docked with the second housing has a through hole in its middle part for serving as a downward channel for the opening grid plate, wherein the third housing forms a third gas channel communicating with the second gas channel. A fourth housing located below the third housing, wherein the fourth housing has a cavity in the middle containing an arc-extinguishing metal mesh, and at least one vent hole is provided at the bottom of the cavity; wherein the fourth housing forms a fourth gas channel communicating with the third gas channel; and The fifth housing located below the fourth housing has a housing cavity with a volume larger than that of the fourth housing, and the housing cavity is in fluid communication with the exhaust port and the fourth gas passage; In this embodiment, the first housing, the second housing, the third housing, the fourth housing, and the fifth housing are tightly laminated together via at least one fastener passing through in the vertical axis direction.

2. The intelligent excitation fuse (100) as described in claim 1, characterized in that, The first housing also includes a one-way valve located at the upper end of the first gas passage, wherein the one-way valve is designed to control the fluid communication between the first gas passage and the external atmospheric environment.

3. The intelligent excitation fuse (100) as described in claim 1 or 2, characterized in that, It also includes a seal sandwiched between the first housing and the second housing, the second housing and the third housing, and the third housing and the fourth housing.

4. The intelligent excitation fuse (100) as described in claim 1 or 2, characterized in that, The arc-extinguishing metal mesh has a generally rectangular cross-section and a recessed portion in the central part that is substantially the same as the cross-section of the breaking grid plate, serving as a downward channel for the breaking grid plate, so as to allow the downward breaking grid plate to be inserted into the recessed portion.

5. The intelligent excitation fuse (100) as described in claim 4, characterized in that, It also includes a filter element sandwiched between the arc-extinguishing metal mesh and the bottom of the receiving cavity, wherein the filter elements are arranged in pairs about the vertical axis.

6. The intelligent excitation fuse (100) as described in claim 1 or 2, characterized in that, in, The breaking grid includes a grid body that is axisymmetric with respect to a vertical axis and at least one breaking blade disposed therein, wherein the breaking blade has: The innermost surface of the first cutter body; The outermost surface of the second cutter body, which is opposite to the surface of the first cutter body; The cutting edge is located between these two; as well as The cutting tip is located at the lowest point of the cutting edge, in the center of the cutting edge.

7. The intelligent excitation fuse (100) as described in claim 6, characterized in that, The cutting edge is designed to extend obliquely downwards from the cutting tip at the bottom towards both sides of the blade body, wherein the opening angle or blade face angle through which the cutting edge extends is in the range of 210 degrees to 235 degrees.

8. The intelligent excitation fuse (100) as described in claim 6, characterized in that, It includes a pair of cutting blades, wherein the cutting edges of the cutting blades are arranged at an angle such that the opening angle between these cutting edges is in the range of 135 degrees to 165 degrees.

9. The intelligent excitation fuse (100) as described in claim 6, characterized in that, The cutting grid plate also has a cylinder at the end opposite to the cutting edge for at least partially surrounding the gas generator.

10. The intelligent excitation fuse (100) as described in claim 1 or 2, characterized in that, The second and / or third housings are further provided with clearance grooves that correspond to the breakage notch of the conductive busbar, so as to allow the part of the conductive busbar to be forced into the clearance groove after it is broken.

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