Excitation fuse structure
By lengthening the distance between the piston and the ignition device in the excitation fuse and adopting an inner and outer shell and gas passage structure, the problem of large impact on the shell of the traditional excitation fuse is solved, achieving higher heat dissipation efficiency and breaking reliability, and reducing production costs.
Patent Information
- Application Number
- CN202423178433.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2025-11-18
- Estimated Expiration
- 2034-12-23
AI Technical Summary
Traditional excitation fuses have a small gap between the ignition device and the piston, which prevents the high-pressure gas from being effectively depressurized, resulting in a large impact force on the casing. This requires high-quality materials and structures, increasing production costs.
By changing the structure of the excitation fuse, the distance between the piston and the ignition device is lengthened. An inner and outer shell design and a gas passage structure are adopted. High-pressure gas is depressurized through the gas passage to drive the piston, reducing the impact force on the shell. A limiting structure is set at the conductor bus disconnection point to improve the disconnection reliability.
The requirements for shell material and structural strength have been reduced, heat dissipation efficiency and breakage reliability have been improved, and production costs have been reduced.
Smart Images
Figure CN223566568U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of electric power control and electric vehicles, and relates to a switching device for electric power / electric vehicles, in particular to a structure of an excitation fuse for circuit protection. BACKGROUND
[0002] As an electric vehicle circuit system protection device, the excitation fuse can break the circuit conductor in a short time (less than 2 ms) through an explosive device as an energy source, realizing full-range protection from zero current to maximum breaking capacity. In contrast to the inverse time relationship of the specific fuse current and breaking time of the traditional fuse, that is, the greater the fuse current, the shorter the fuse time, and the smaller the fuse current, the longer the fuse time. The excitation fuse has obvious advantages and has been widely used in the field of electric vehicles.
[0003] The structure of the excitation fuse generally includes a shell, an ignition device, a piston, and a conductive row. The ignition device and the piston are arranged in the shell on the same side of the conductive row, and the piston is located between the conductive row and the ignition device. The ignition device acts according to the received trigger signal, releases high-pressure gas to drive the piston to displace towards the conductive row, so that the piston has enough kinetic energy to cut off the conductive row, thereby breaking the circuit and realizing circuit protection.
[0004] Although the traditional excitation fuse has a very fast response speed, the distance between the ignition device and the piston is small, that is, the space between the ignition device and the piston is small, and the high-pressure gas released by the ignition device cannot be effectively discharged to the extent of driving the piston to displace, so the impact force generated on the shell and other parts is very large, and the impact damage caused by the shell of the excitation fuse is relatively large. Therefore, the shell material, structure, etc. of the traditional excitation fuse have very high requirements. SUMMARY
[0005] The purpose of the present application is to change the internal structure of the excitation fuse, change the positional relationship between the piston, the arc extinguishing chamber, and the ignition device and the pre-breaking place of the conductive row, maximize the distance between the piston and the ignition device, that is, lengthen the distance from the gas release end of the ignition device to the piston, so that the high-pressure gas released by the ignition device can be discharged through the gas passage to the required extent for driving the piston at the first time, thereby reducing the impact on the shell and reducing the requirements for the shell material and strength.
[0006] To achieve the above object, the technical scheme of the present application is a structure of an excitation fuse, comprising a shell, the shell comprising an inner shell and an outer shell, the inner shell being provided in the outer shell with an open end and being hollow inside, an air passage being provided between the inner shell and the outer shell and being in communication with the open end of the inner shell; a piston being provided in the open end of the inner shell, an arc extinguishing structure being provided in the other end of the inner shell opposite to the open end, the piston being in sealing contact with the inner wall of the inner shell; a conductive row being provided through the outer shell and the inner shell in a manner that the conductive row is located on the displacement path of the piston, an ignition device being provided in the part of the outer shell away from the open end of the inner shell, and the gas releasing end of the ignition device being in communication with the air passage; the high pressure gas released by the ignition device driving the piston to displace from the open end of the inner shell to the conductive row located in the inner shell through the air passage, the piston breaking the conductive row.
[0007] Preferably, a limiting structure is provided between the conductive row and the arc extinguishing structure, the conductive row breaking part being driven by the piston into the limiting structure, the limiting structure limiting the conductive row breaking part.
[0008] Preferably, the end of the piston towards the arc extinguishing structure can enter the limiting structure after breaking the conductive row, the limiting structure limiting the terminal position of the piston.
[0009] Preferably, the limiting structure is a limiting sleeve or a limiting sheet fixedly attached to the inner wall of the inner shell.
[0010] Preferably, the arc extinguishing structure is a porous structure of metal material.
[0011] Preferably, the two ends of the conductive row located outside the shell are located on the two sides of the end of the shell towards which the open end of the inner shell, the part of the conductive row located in the inner shell being located on the displacement path of the piston.
[0012] Preferably, a gap is reserved between the outer periphery of the inner shell and the inner wall of the outer shell as the air passage, the inner shell being fixedly connected in the outer shell through connecting ribs.
[0013] Preferably, cavities are respectively reserved between the open end of the inner shell and the other end corresponding to the open end of the inner shell and the inner wall of the outer shell, passages being respectively provided on the opposite sides between the outer periphery of the inner shell and the inner wall of the outer shell, the cavities and the passages being in communication to form the air passage.
[0014] Preferably, the ignition device is arranged on the corresponding end of the outer shell away from the open end of the inner shell, or arranged on the corresponding side wall of the outer shell away from the open end of the inner shell.
[0015] Preferably, the shell comprises a first shell, a second shell and a bottom cover, the first shell comprises a first part of the outer shell and a first part of the inner shell located in the first part of the outer shell, a first part of the air passage is arranged between the first part of the inner shell and the first part of the outer shell, and the first part of the inner shell is open at one end; the second shell is integrally formed with the conductive row, the second shell comprises a second part of the outer shell and a second part of the inner shell located in the second part of the outer shell, a second part of the air passage is arranged between the second part of the inner shell and the second part of the outer shell, and both ends of the second part of the inner shell and the second part of the outer shell are through; the first part and the second part of the inner shell are spliced to form the inner shell, the first part and the second part of the outer shell are spliced to form the outer shell, the first part and the second part of the air passage are spliced to form the air passage, and the bottom cover closes the end of the second part of the outer shell away from the first shell. The ignition device and the piston are arranged as far away from each other as possible, the air passage is lengthened, the gas volume is increased, the purpose of reducing the pressure of the high-pressure gas released by the ignition device is achieved, the impact of the high-pressure gas released by the ignition device on the shell is reduced, the requirements for the material strength and structural strength of the shell are reduced, and the production cost of the product is reduced.
[0016] By arranging the conductive row in a U-shaped structure, the two ends of the conductive row as the connection terminals are arranged at the end of the shell, the air passage is arranged between the inner shell and the outer shell, the piston is arranged away from the ignition device, the distance between the pre-break of the conductive row and the two ends of the conductive row is shortened, the overall length of the conductive row is shortened, and the heat dissipation efficiency is improved. At the same time, the conductive row as the connection terminals is arranged at the end of the shell in a flat-out structure, the connection terminals of the energized fuse are directly connected and installed with the battery pack cooling system, the heat dissipation distance is shortened, and the heat dissipation efficiency is improved.
[0017] By arranging a limiting structure on the displacement path of the pre-break of the conductive row, the position of the pre-break of the broken conductive row is limited, the broken pre-break is prevented from falling back, the conductive row is prevented from being re-conducted, and the breaking reliability is improved; after the piston is displaced, the broken end of the conductive row is insulated and isolated by the insulation of the piston itself, and the breaking reliability is further improved. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 is a longitudinal sectional view of the cross section of the energized fuse in the initial position along the flow direction of the air passage.
[0019] Figure 2 is Figure 1 the structure diagram of the termination position of the conductive row after being disconnected.
[0020] Figure 3 is the cross-sectional structure diagram of the air channel gap between the inner shell and the outer shell.
[0021] Figure 4 is the cross-sectional structure diagram of the air channel gap between the inner shell and the outer shell.
[0022] Figure 5 is the structure diagram of the ignition device arranged on the side wall of the outer shell.
[0023] Reference signs:
[0024] The outer shell 10, the inner shell 11, the bottom cover 12, the air channel 13, the connecting rib 14, the conductive row 15, the pre-disconnection position 15a, the piston 16, the ignition device 17, the arc extinguishing structure 18, and the limiting structure 19. DETAILED DESCRIPTION
[0025] The structure of the excitation fuse of the application comprises a shell, the shell comprises an inner shell and an outer shell, the inner shell is arranged in the outer shell and has an open end and an inner cavity, an air channel is arranged between the inner shell and the outer shell and communicates with the open end of the inner shell; a piston is arranged in the open end of the inner shell, an arc extinguishing structure is arranged in the other end of the inner shell opposite to the open end, and the piston is in sealing contact with the inner wall of the inner shell; a conductive row passes through the outer shell and the inner shell in a manner of being located on the displacement path of the piston, an ignition device is arranged in the part of the outer shell away from the open end of the inner shell, and the gas release end of the ignition device communicates with the air channel; the high-pressure gas released by the ignition device drives the piston to displace from the open end of the inner shell to the conductive row located in the inner shell through the air channel, and the piston disconnects the conductive row.
[0026] The ignition device and the arc extinguishing structure are located on the same side of the conductive row and are arranged away from the open end of the inner shell, the air channel is lengthened, the volume of the air channel is increased, the high-pressure gas released by the ignition device is instantaneously depressurized after entering the air channel, and the impact force of the high-pressure gas on the shell is reduced by lengthening the air channel. The conductive row is arranged close to one end of the shell, the length of the conductive row is shortened, and the heat dissipation efficiency is improved. Since the length of the conductive row is shortened and the air channel is lengthened, the overall weight of the product is reduced.
[0027] The shell of the excitation fuse can be formed by splicing several parts, and can be spliced by two parts, three parts, four parts or more parts. The specific structure of the shell is determined according to design requirements and processing conditions.
[0028] The gap between the outer periphery of the inner shell and the inner wall of the outer shell forms an annular air passage around the outer periphery of the inner shell. The air passage has the maximum width and volume. One side of the outer periphery of the inner shell and one side of the inner wall of the outer shell are integrally connected, or two or three sides of the outer periphery of the inner shell are integrally connected with the corresponding inner wall of the outer shell. The unconnected part of the inner shell and the outer shell is designed as an air passage, which is in communication with the open end of the inner shell. The design of the air passage is not limited to the above structure. The design of the air passage meets the communication with the open end of the inner shell, and is convenient for communication with the high-pressure gas release end of the ignition device. Moreover, the air passage combined with the ignition device is arranged on the outer shell away from the open end of the inner shell, so that the high-pressure gas released by the ignition device flows along the annular air passage from the position where the other end of the open end of the inner shell is located or close to the position, ensuring that the high-pressure gas flows along the outer periphery of the inner shell from the air passages on both sides of the position where the ignition device is located, lengthening the distance of the air passage actually passed by the high-pressure gas, and reducing the pressure of the high-pressure gas released by the ignition device as much as possible, and reducing the impact on the shell.
[0029] The preferred embodiments are described below in detail with reference to the drawings, which are only used to illustrate the technical solutions of the present application and do not constitute a limitation on the technical solutions of the present application. The orientation words involved are only based on the orientation shown in the drawings and do not constitute a limitation on the technical solutions of the present application.
[0030] The fuse is excited, referring to Figures 1 to 3 The shell includes an outer shell 10, an inner shell 11 and a bottom cover 12. The outer shell 10 and the inner shell 11 are both hollow structures with one end open and one end closed. The inner shell 11 is located in the outer shell 10, and the open ends of the inner shell 11 and the outer shell 10 are located at the same end, and the closed ends are located at the same end. The bottom cover 12 closes the open end of the outer shell 10, forming a closed annular gap between the inner shell 11 and the outer shell 10, which forms an air passage 13 between the inner shell 11 and the outer shell 10, which is in communication with the open end of the inner shell 11, referring to Figure 3 The inner shell 11 and the outer shell 10 are connected and fixed by a plurality of connecting ribs 14. In other embodiments, the closed end of the inner shell can also be designed as an incomplete closed structure, such as a small gap exhaust hole, but the existence of the exhaust hole should not affect the action of the piston breaking the conductive row.
[0031] The conductive row 15 is made of metal conductive material and is arranged in the shell 10 and the inner shell 11 in a U-shaped structure. The pre-breakage part 15a of the conductive row 15 is located in the cavity of the inner shell 11. The pre-breakage part of the conductive row 15 is the part where the conductive row is broken by the piston. The two ends of the pre-breakage part of the conductive row 15 are arranged as mechanical breakage weak parts with reduced mechanical strength at the contact position with the inner wall of the inner shell 11. The mechanical breakage weak part can have various structures, such as a groove, a variable cross-section structure, an easy-to-break lap joint structure, etc. In this embodiment, the mechanical breakage weak part is designed as a V-shaped groove. The two ends of the conductive row 15 are located outside the end of the opening end of the outer shell 10, and are preferably flush with the end of the outer shell, so as to facilitate the installation of the actuating fuse on the water-cooled plate A. The smaller the vertical distance H between the two ends of the conductive row 15 and the pre-breakage part of the conductive row 15, the smaller the length of the conductive row 15, the easier the heat energy inside the actuating fuse shell is dissipated to the outside of the shell through the conductive row, the higher the heat dissipation efficiency, and the lower the product weight.
[0032] The piston 16 is made of insulating material and is located in the opening end of the inner shell 11 between the conductive row 15 and the bottom cover 12. The piston is in sealing contact with the inner wall of the inner shell 11. The sealing contact can be achieved in various ways, such as arranging a sealing ring on the outer periphery of the piston 16 to achieve the sealing contact between the piston 16 and the inner wall of the cavity of the inner shell 11. Alternatively, the piston 16 can be arranged in the opening end of the inner shell 11 through interference fit to achieve the sealing contact between the piston 16 and the inner shell 11. However, the interference fit degree between the piston and the inner shell must meet the requirement that the piston can be broken by the high-pressure gas released by the ignition device. The ignition device 17 is a gas generating device and can act according to the received trigger signal to release high-pressure gas as driving force. The ignition device 17 is arranged on the closed end of the outer shell 10, and the high-pressure gas release end of the ignition device 17 is located at the air passage between the outer shell and the inner shell and communicates with the air passage 13. The high-pressure gas released by the ignition device 17 can enter the opening end of the inner shell 11 through the air passage 13 at the closed end of the inner shell 11 to act on the piston 16.
[0033] An arc extinguishing structure 18 is arranged in the end where the closed end of the inner shell 11 is located. The arc extinguishing structure 18 is a porous structure made of metal material or non-metal material with good heat conductivity, and is preferably made of metal material. The porous structure can be a wire mesh structure or a metal grid structure. A displacement distance is reserved between the arc extinguishing structure and the pre-breakage part of the conductive row 15 for the pre-breakage part of the conductive row 15 after being broken.
[0034] The limiting structure 19 is arranged between the pre-breakage of the conductive strip 15 and the arc extinguishing structure 18, and is used to limit the position of the pre-breakage of the conductive strip 15 after the conductive strip 15 is broken. The limiting structure 19 can be a hollow sleeve structure, which is arranged on the inner wall of the inner shell in an interference fit, and one end is clamped in the V-shaped groove at the mechanical breaking weak position of the conductive strip, and the other end is located between the arc extinguishing structure 18 and the inner wall of the inner shell. When the conductive strip 15 is broken, the pre-breakage of the conductive strip 15 enters the limiting structure 19, and the two ends of the pre-breakage of the conductive strip are fitted with the inner wall of the limiting structure 19 in an interference fit. The limiting structure 19 can also be a limiting plate structure, which is fixedly arranged on the opposite sides of the cavity in the inner shell 11, one end is clamped in the V-shaped groove at the mechanical breaking weak position of the conductive strip, and the other end is located between the arc extinguishing structure 18 and the inner wall of the inner shell. When the conductive strip 15 is broken, the pre-breakage of the conductive strip 15 enters the limiting structure 19, and the two ends of the pre-breakage of the conductive strip are arranged in the limiting structure 19 on the opposite sides of the inner shell 11 in an interference fit.
[0035] In order to facilitate assembly, in Figures 1 to 2 The outer shell 10 and the inner shell 11 are respectively divided into two parts that are spliced with each other: the outer shell first part and the inner shell first part fixedly connected by the connecting rib 14, and the outer shell second part and the inner shell second part. The two ends of the outer shell first part are through, and one end of the inner shell first part is open and the other end is closed, wherein the closed end of the inner shell first part corresponds to the end of the outer shell first part closed by the top cover to form the closed end of the outer shell. The two ends of the outer shell second part and the inner shell second part are through, and the open end of the inner shell first part and the open end of the outer shell first part are respectively butted with the outer shell second part and the inner shell second part, and then the end of the outer shell second part away from the top cover is closed by the bottom cover. The arc extinguishing structure 18 and the limiting structure 19 are arranged in the inner shell first part, the ignition device is arranged in the outer shell first part or the top cover, and the conductive strip is arranged in the outer shell second part and the inner shell second part.
[0036] Working principle:
[0037] When the ignition device 17 releases high pressure gas according to the action of receiving the trigger signal, the high pressure gas drives the piston 16 to displace along the direction of the arrow in the gas channel 13 from the closed end to the open end of the inner housing, the piston 16 breaks the break in the inner housing to form the conductive row, the broken conductive row pre-break enters the limiting structure 19 under the drive of the piston 16 and is limited by the limiting structure 19, and the piston 16 is located at the break of the conductive row in the inner housing, so as to insulate the break of the conductive row. The electric arc generated when the conductive row is broken enters the arc extinguishing structure under the drive of the piston, the metal wire mesh structure adsorbs and cuts the electric arc into multiple sections, and the temperature of the electric arc is reduced through the metal wire mesh structure to achieve arc extinguishing.
[0038] In other embodiments, the gas channel 13 can also be other structures, refer to Figure 4 , the inner housing 11 and the outer housing 10 are square structures, the left and right or front and back opposite sides of the inner housing 11 and the outer housing 10 are provided with the gas channel 13, and the other opposite sides are integrally connected. Figure 3 and Figure 4 The gas channel 13 in the longitudinal cross-sectional direction is in a ring structure as shown in Figure 1 .
[0039] The position of the ignition device 17 is only required to be communicated with the gas channel 13, and the high pressure gas released by the ignition device 17 can pass through the longer gas channel as much as possible to achieve the purpose of pressure relief, and the gas after pressure relief can drive the piston to displace and break the conductive row, and is not limited to be arranged at the closed end of the outer housing 10. Refer to Figure 5 , the ignition device 17 is arranged on the side wall of the outer housing 10 away from the open end of the inner housing, Figure 5 The arrow in the gas channel in the above represents the path of the gas passing through.
Claims
1. An excitation fuse structure, characterized in that, The device includes a housing, which comprises an inner housing and an outer housing. An inner housing with an open end and a hollow interior is disposed within the outer housing. An air passage is disposed between the inner housing and the outer housing and communicates with the open end of the inner housing. A piston is disposed in the open end of the inner housing, and an arc-extinguishing structure is disposed in the other end of the inner housing opposite to the open end. The piston is in sealed contact with the inner wall of the inner housing. The conductive busbar passes through the outer shell and the inner shell in a manner located on the piston displacement path. The ignition device is disposed in the outer shell portion away from the opening end of the inner shell, and one gas release end of the ignition device is connected to the gas passage. The high-pressure gas released by the ignition device drives the piston to move from the opening end of the inner shell toward the conductive busbar located in the inner shell through the gas passage, and the piston disconnects the conductive busbar.
2. The excitation fuse structure according to claim 1, characterized in that, A limiting structure is provided between the conductive busbar and the arc extinguishing structure. The piston drives the disconnected portion of the conductive busbar into the limiting structure, and the limiting structure limits the disconnected portion of the conductive busbar.
3. The excitation fuse structure according to claim 2, characterized in that, After the conductive busbar is disconnected, the piston, facing the arc-extinguishing structure, can enter the limiting structure, which limits the piston's termination position.
4. The excitation fuse structure according to claim 2, characterized in that, The limiting structure is a limiting sleeve or limiting piece that is fixedly fitted to the inner wall of the inner shell.
5. The excitation fuse structure according to claim 1, characterized in that, The arc-extinguishing structure is a porous structure made of metal.
6. The excitation fuse structure according to claim 1, characterized in that, The two ends of the conductive busbar located outside the housing are respectively located on both sides of the end of the housing facing the opening end of the inner housing, and the conductive busbar portion located in the inner housing is located on the piston displacement path.
7. The excitation fuse structure according to claim 1, characterized in that, A gap is maintained between the outer periphery of the inner shell and the inner wall of the outer shell to serve as the air passage, and the inner shell is connected and fixed in the outer shell by connecting ribs.
8. The excitation fuse structure according to claim 1, characterized in that, The inner shell has cavities between its open end and the other end corresponding to the open end and the inner wall of the outer shell. Channels that run through the length of the inner shell are opened on opposite sides between the outer periphery of the inner shell and the inner wall of the outer shell. The cavities and the channels are connected to form the air passage.
9. The excitation fuse structure according to any one of claims 7 or 8, characterized in that, The ignition device is disposed on one end of the outer shell corresponding to the other end away from the opening end of the inner shell, or disposed on the side wall of the outer shell corresponding to the side wall of the inner shell and away from the opening end of the inner shell.
10. The excitation fuse structure according to any one of claims 1 to 8, characterized in that, The housing includes a first housing, a second housing, and a bottom cover, all joined together. The first housing includes a first portion of the outer shell and a first portion of the inner housing located within the first portion of the outer shell. A first portion of the air passage is provided between the first portion of the inner housing and the first portion of the outer shell, and one end of the first portion of the inner housing is open. The second housing is integrally formed with the conductive busbar. The second housing includes a second portion of the outer shell and a second portion of the inner housing located within the second portion of the outer shell. A second portion of the air passage is provided between the second portion of the inner housing and the second portion of the outer shell, and both ends of the inner housing and the second portion of the outer shell are through-through. The first and second portions of the inner housing are joined together to form the inner housing, the first and second portions of the outer shell are joined together to form the outer shell, and the first and second portions of the air passage are joined together to form the air passage. The bottom cover closes the end of the second portion of the outer shell away from the first housing.