A high breaking capacity fuse

Abstract

The present application relates to a high-breaking-power fuse, comprising a protective tube; a contact blade, which is sealed and arranged on both ends of the protective tube, and is used to form an arc-extinguishing cavity on the inner side of the protective tube; a fuse, which is arranged in the arc-extinguishing cavity; a conductive connecting piece, which is arranged at the disconnection point between the fuse and the circuit where the contact blade is located; an overload installation box, which is arranged in the arc-extinguishing cavity, and the overload installation box is provided with a mounting cavity and a connecting hole; a connecting rod, one end of which is arranged in the mounting cavity, and the other end slides in and out of the connecting hole, and an arc-extinguishing filling area connected to the connecting hole is formed between the mounting cavity and the connecting rod; a connecting solder, which is arranged between the fuse and the end of the connecting rod outside the mounting cavity, and is used to conduct the disconnection point between the fuse and the circuit where the contact blade is located; a breaking spring, which is connected to the connecting rod and is used to retract the connecting rod into the mounting cavity; and an arc-extinguishing medium, which is filled with overpressure and arranged in the arc-extinguishing cavity. The present application has the effect of improving the arc-extinguishing performance of the fuse.

Description

Technical Field

[0001] The present application relates to the field of fuses, and in particular to a high breaking capacity fuse. Background Art

[0002] With the continuous development of power technology, science and technology and economy have played a driving role in the transformation of power technology. The reliability requirements for power systems are becoming increasingly higher. Therefore, fuses will be added to the power system to protect the power system.

[0003] In the related art, such as publication number CN114429890A, a low-multiple small-break fuse includes a fixed terminal 1, a fuse element 2, a movable terminal 3, an arc-extinguishing tube 4, and an outer cap 5. The fuse element 2 is fixed to the fixed terminal 1; there is a distance between the movable terminal 3 and the fuse element 2; the arc-extinguishing tube 4 is sleeved on the fixed terminal 1 and the movable terminal 3, and serves to fix the fixed terminal 1 and the movable terminal 3. A sleeve 31, a connector 32, and a first spring 33 are provided on the movable terminal 3. The connector 32 and the sleeve 31 are slidably connected; the first spring 33 drives the connector 32 to move in a direction away from the fuse element 2; the connector 32 and the fuse element 2 are fixed by soldering. The sleeve 31 is fixed to the movable terminal 3. When the connector 32 and the fuse element 2 are fixed, the movable terminal 3 and the fixed terminal 1 are electrically connected through the fuse element 2, the connector 32, the sleeve 31, and the first spring 33.

[0004] After the arc extinguishing tube 4 is installed on the fixed terminal 1 and the movable terminal 3, an arc extinguishing agent is also filled in the arc extinguishing tube 4. The arc extinguishing agent fills the entire arc extinguishing tube, and the arc is released by the arc extinguishing agent, reducing the impact of the arc on the overall structure. In the example, the arc extinguishing agent is preferably arc extinguishing sand to reduce the weight of the entire fuse. Since arc extinguishing sand has high thermal conductivity and insulation properties, it has a large contact area with the arc, which is convenient for absorbing arc energy, and thus can quickly cool the arc. When the connector 32 is slidably set at the opening of the sleeve 31, the sleeve 31 provides a sliding space for the connector 32, and the sleeve 31 protects the connector 32. Try to avoid arc extinguishing sand from filling into the sleeve 31 during the filling process, which will hinder the movement of the connector 32.

[0005] Regarding the above-mentioned related technologies, there is a defect that the arc extinguishing sand cannot be filled into the sleeve when the connecting piece is moved into the sleeve, so the connecting piece is not completely isolated by the arc extinguishing sand after being disconnected from the fuse link, resulting in poor arc extinguishing performance of the fuse. Summary of the Invention

[0006] In order to improve the arc extinguishing performance of the fuse, the present application provides a high breaking capacity fuse.

[0007] The high breaking capacity fuse provided in this application adopts the following technical solution:

[0008] A high breaking capacity fuse, comprising:

[0009] protective tube;

[0010] Contact blades are sealed and arranged on both ends of the protection tube, and are used to form an arc extinguishing cavity inside the protection tube;

[0011] A fuse, disposed in the arc extinguishing chamber;

[0012] A conductive connecting piece, provided at a disconnection point between the fuse and the circuit where the contact knife is located;

[0013] An overload installation box is arranged in the arc extinguishing chamber, and the overload installation box is provided with an installation cavity and a communicating hole;

[0014] A connecting rod, one end of which is disposed in the installation cavity and the other end of which slides in and out of the communicating hole, wherein an arc extinguishing filling area connected to the communicating hole is formed between the installation cavity and the connecting rod;

[0015] Connecting solder, provided between the fuse and one end of the connecting rod outside the mounting cavity, for conducting the disconnection between the fuse and the circuit where the contact knife is located;

[0016] a breaking spring connected to the connecting rod and used to retract the connecting rod into the installation cavity;

[0017] An arc extinguishing medium is filled with overpressure and is arranged in the arc extinguishing chamber.

[0018] By adopting the above technical solution, after the connecting solder is melted, the disconnecting spring will use its own elastic force to retract the connecting rod into the installation cavity. At the same time, the arc extinguishing sand that was originally in an overpressure state will be pressure-released and quickly enter the arc extinguishing filling cavity, so that the gap between the connecting rod and the fuse will be completely filled without hindering the retraction movement of the connecting rod, thereby completely isolating the connecting rod and the fuse, thereby helping to improve the arc extinguishing performance of the fuse.

[0019] Preferably, the end of the connecting rod close to the connecting solder is in a frustum shape, and the smaller the cross-sectional area of ​​the connecting rod, the closer the end is to the connecting solder.

[0020] By adopting the above technical solution, compared with the columnar structure of the connecting rod, with this design, when the connecting rod starts to move into the installation cavity, a gap will open between the outer wall of the connecting rod and the inner wall of the connecting hole to allow the arc extinguishing sand to enter the arc extinguishing filling area. In this process, the movement of the connecting rod can also make use of the fluidity of the arc extinguishing sand to make its own movement smoother, thereby making the disconnection between the connecting rod and the fuse faster, which in turn helps to improve the arc extinguishing performance.

[0021] Preferably, the arc-extinguishing sand is made of quartz sand.

[0022] By adopting the above technical solution, the quartz sand is in the form of small particles, so it is not easy for the quartz sand to block the gap between the outer wall of the connecting rod and the inner wall of the connecting hole, so the smoothness of the retraction movement of the connecting rod into the installation cavity can be maintained.

[0023] Preferably, a force ring is sleeved on one end of the connecting rod away from the connecting solder; the disconnecting spring is in the installation cavity, the disconnecting spring is sleeved on the connecting rod, and the disconnecting spring abuts against the surface of the force ring close to the connecting solder.

[0024] By adopting the above technical solution, on the one hand, the disconnecting spring 8 is placed in the installation cavity, which can more easily prevent arc extinguishing sand from entering the installation cavity before the connecting solder is melted, thereby maintaining the rapid disconnection movement of the subsequent connecting active rod; on the other hand, the disconnecting spring 8 is sleeved on the connecting active rod, and the inner diameter of the disconnecting spring 8 can be larger, so a disconnecting spring 8 with a larger elastic coefficient can be selected to accelerate the retraction of the connecting active rod into the installation cavity, thereby making the disconnection between the connecting active rod and the fuse faster, which also helps to improve the arc extinguishing performance.

[0025] Preferably, two fuses are provided, and the overload mounting box is provided at the interval between the two fuses, so that the overload mounting box is located in the middle position between the two contact knives; one end of the conductive connecting piece is connected to the end of the connecting rod outside the mounting cavity, and the other end is connected to the fuse away from the connecting solder.

[0026] By adopting the above technical solution, the overload installation box is located in the middle of the fuse, and the heat of the fuse will be concentrated in the middle position. Therefore, when the fuse encounters a small current overload, the connecting solder can also be melted, which helps to improve the breaking performance of the fuse.

[0027] Preferably, the overload mounting box includes a heat dissipation cap and an insulating isolation cap, the heat dissipation cap is made of metal, the cap groove of the heat dissipation cap is for the connection rod to be set, and the bottom of the cap groove of the heat dissipation cap is for the connection rod to pass through to form the connecting hole; the cap groove of the insulating isolation cap is for the heat dissipation cap to be set, the cap groove of the insulating isolation cap is facing the direction of the connecting solder, and the insulating isolation cap is located between the conductive connecting plate and the heat dissipation cap.

[0028] By adopting the above technical solution, on the one hand, the larger surface area of ​​the heat dissipation cap can be used to dissipate the heat accumulated in the overload installation box more quickly, so as to significantly reduce the ambient temperature of the fuse, thereby increasing the ambient temperature of the fuse, thereby achieving a compatible balance between the overload performance of the fuse and the temperature resistance of the application environment; on the other hand, because the heat dissipation cap is made of metal, the setting of the insulating isolation cap can insulate and isolate the conductive connecting piece from the heat dissipation cap, thereby maintaining the safe use of the fuse.

[0029] Preferably, the conductive connecting piece is divided into a conductive input ring, a transfer piece and a collecting piece. The conductive input ring is sleeved on the end of the connecting rod outside the mounting cavity; one end of the transfer piece is connected to the conductive input ring, and the other end extends in the direction away from the connecting solder. Two transfer pieces are symmetrically arranged relative to the center of the conductive input ring, and the area between the two transfer pieces is used to accommodate the overload mounting box; two collecting pieces are arranged, and the ends of the two collecting pieces that are close to each other are connected to the end of the transfer piece away from the conductive input ring, and the ends away from each other are connected to the fuse.

[0030] By adopting the above technical solution, after passing through the connecting rod, the current will be divided into two streams and transmitted along the conductive input ring to the two transmission plates respectively, and then merged through the two collecting plates and transmitted to the fuse. In this process, the heat transferred from the conductive connecting plate to the overload installation box is more uniform, thereby promoting heat dissipation at the overload installation box.

[0031] Preferably, the conductive connection is integrally formed into a rectangular frame shape, the overload installation box is located on the inner side of the conductive connection piece, and the overload installation box abuts against the inner side of the conductive connection piece.

[0032] By adopting the above technical solution, the overload mounting box can be directly fixed on the inner side of the conductive connecting piece, thereby making the structural form of the overload structure simpler and more compact, and thus enabling the fuse to select a structural form with more fuse holes, which helps to improve the voltage level of the fuse.

[0033] Preferably, a sealing solder is provided on a side of the conduction input ring away from the overload installation box, and the sealing solder is connected to the outer wall of the connecting rod to seal and block the communicating hole.

[0034] By adopting the above technical solution, before the arc extinguishing sand is filled, a sealing solder is provided on the end of the connecting rod outside the installation cavity to improve the sealing of the overload installation box, thereby maintaining the normal operation of subsequent arc extinguishing operations.

[0035] In summary, this application includes at least one of the following beneficial technical effects:

[0036] 1. After the connecting solder is melted, the disconnect spring will use its own elastic force to retract the connecting rod into the installation cavity. At the same time, the arc-extinguishing sand that was originally in an over-pressure state will be pressure-released and quickly enter the arc-extinguishing filling cavity, so that the gap between the connecting rod and the fuse will be completely filled without hindering the retraction of the connecting rod. This can completely isolate the connecting rod and the fuse, thereby helping to improve the arc-extinguishing performance of the fuse;

[0037] 2. On the one hand, the heat dissipation cap can be used to dissipate the heat accumulated in the overload installation box to reduce the ambient temperature of the fuse, thereby increasing the ambient temperature of the fuse, thereby achieving a compatible balance between the overload performance of the fuse and the temperature resistance of the application environment; on the other hand, because the heat dissipation cap is made of metal, the setting of the insulating isolation cap can insulate and isolate the conductive connecting piece from the heat dissipation cap, thereby maintaining the safe use of the fuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural diagram of a high breaking capacity fuse in an embodiment of the present application.

[0039] Figure 2 This is a schematic diagram of the specific structure of the overload fuse structure after the connecting rod is retracted in the embodiment of the present application.

[0040] Figure 3 This is a schematic diagram of how the conductive connecting piece and the overload installation box are assembled in an embodiment of the present application.

[0041] Explanation of the accompanying symbols: 1. Protective tube; 11. Arc extinguishing chamber; 2. Contact knife; 3. Fuse; 4. Conductive connecting piece; 41. Conductive input ring; 42. Transfer piece; 43. Collection piece; 5. Overload installation box; 51. Installation cavity; 52. Connecting hole; 53. Arc extinguishing filling area; 54. Heat dissipation cap; 55. Insulating isolation cap; 6. Connecting rod; 61. Force ring; 7. Connecting solder; 8. Disconnecting spring; 9. Arc extinguishing sand; 10. Sealing solder. DETAILED DESCRIPTION

[0042] The following is combined with Figure 1-3 This application is described in further detail.

[0043] The embodiment of the present application discloses a high breaking capacity fuse. Figure 1 and Figure 2The high breaking capacity fuse includes a protection tube 1, a contact knife 2, a fuse 3, a conductive connecting piece 4, an overload installation box 5, a connecting rod 6, a connecting solder 7, a breaking spring 8 and an arc extinguishing sand 9. The protection tube 1 is in the shape of a round tube; there are two contact knives 2, which are coaxially arranged at both ends of the protection tube 1. At the same time, the two contact knives 2 will seal and block the two ends of the protection tube 1 to form an arc extinguishing cavity 11 on the inner side of the protection tube 1; the fuse 3 is arranged in the arc extinguishing cavity 11, and the fuse 3 adopts Due to the setting of the short-circuit fuse 3, the fuse 3 will have a fuse hole; the conductive connecting piece will be set at the disconnection point of the circuit where the fuse 3 and the contact knife 2 are located to form a circuit structure other than the fuse switch structure; the overload installation box 5 is set in the arc extinguishing chamber 11, and the overload installation box 5 is provided with an installation cavity 51 and a connecting hole 52. The installation cavity 51 is cylindrical in shape, and the connecting hole 52 is circular. The connecting hole 52 is connected to one end of the installation cavity 51, and the connecting hole 52 is coaxially arranged with the protective tube 1.

[0044] Reference Figure 1 and Figure 2 One end of the connecting rod 6 is in the installation cavity 51, and the other end slides in and out of the connecting hole 52. When the connecting rod 6 is completely in the installation cavity 51, there will be an arc extinguishing filling area 53 between the installation cavity 51 and the connecting rod 6, and the arc extinguishing filling area 53 is connected to the connecting hole 52; the connecting solder 7 will connect the end of the connecting rod 6 outside the installation cavity 51 with the fuse 3. At this time, the fuse 3, the connecting rod 6, the conductive connecting piece 4 and the contact knife 2 form a connected circuit, and the connecting rod 6 serves as a switch structure for the entire circuit to be melted; the disconnecting spring 8 is connected to the connecting rod 6, and after the connecting solder 7 is melted, the disconnecting spring 8 will retract the connecting rod 6 into the installation cavity 51 to disconnect the connecting rod 6 from the fuse 3; the arc extinguishing sand 9 is filled in the arc extinguishing cavity 11, and the arc extinguishing cavity 11 will have a certain pressure in the arc extinguishing cavity 11, that is, it will be filled relatively densely.

[0045] Reference Figure 1 and Figure 2 In summary, after the connecting solder 7 is melted, the disconnecting spring 8 will use its own elastic force to retract the connecting rod 6 into the installation cavity 51. At the same time, the arc extinguishing sand 9 that was originally in an overpressure state will be pressure-released and quickly enter the arc extinguishing filling cavity, so that the gap between the connecting rod 6 and the fuse 3 can be completely filled, and at the same time, the retraction movement of the connecting rod 6 will not be hindered, thereby forming a complete isolation effect on the connecting rod 6 and the fuse 3, which helps to improve the arc extinguishing performance of the fuse.

[0046] Reference Figure 1 and Figure 2In order to further improve the arc extinguishing performance, it is necessary to make the process of backfilling the arc extinguishing sand 9 into the arc extinguishing filling area 53 smoother and faster, and the corresponding settings are as follows: first, the arc extinguishing sand 9 can be made of quartz sand with smaller particles; second, the connecting rod 6 is in a truncated cone shape at one end close to the connecting solder 7, and the cross-sectional area of ​​the end of the connecting rod 6 closer to the connecting solder 7 is smaller. When the connecting rod 6 begins to retract into the installation cavity 51, a gap will open between the outer wall of the connecting rod 6 and the inner wall of the communicating hole 52 to allow the arc extinguishing sand 9 to flow in. Therefore, the connecting rod 6 can also use the flow of the arc extinguishing sand 9 to improve its own retraction smoothness, thereby making the disconnection between the connecting rod 6 and the fuse 3 more convenient, which helps to improve the arc extinguishing performance.

[0047] Reference Figure 1 and Figure 2 Thirdly, a force ring 61 is integrally provided on the coaxial sleeve of the end of the connecting rod 6 away from the connecting solder 7. At the same time, the disconnecting spring 8 is arranged in the installation cavity 51. The disconnecting spring 8 is also sleeved on the connecting rod 6. The disconnecting spring 8 also abuts against the surface of the force ring 61 on one side close to the connecting solder 7. The disconnecting spring 8 can use a structure with a larger inner diameter, so the elastic coefficient of the disconnecting spring 8 can be larger, so the disconnecting spring 8 can retract the connecting rod 6 into the installation cavity 51 more quickly, which also helps to improve the arc extinguishing performance.

[0048] Reference Figure 1 A Tianya 2, in order to make the fuse adaptable to the situation of small current overload, the following settings are corresponding. Specifically, two fuses 3 are provided, and the ends of the two fuses 3 away from each other are respectively connected to the two contact blades 2, and the ends of the two fuses 3 close to each other are intermittently arranged, wherein the intermittent part is provided for the overload installation box 5 to be set. At the same time, one end of the conductive connecting piece 4 is in contact with the end of the connecting rod 6 outside the installation cavity 51, and the other end is connected to the capacity piece away from the connecting solder 7. In summary, the heat accumulated by the fuse is in the middle, which is also in the area where the connecting solder 7 is located. Therefore, in the case of a small current overload, the connecting solder 7 can also be melted, thereby improving the breaking performance of the fuse.

[0049] Reference Figure 1 and Figure 2, because heat will be concentrated at the location of the overload installation box 5, but in order to prevent the temperature at the location of the fuse 3 from being too high, and to prevent the fuse 3 from being melted but the connecting solder 7 from being melted, the following settings are correspondingly provided. Specifically, the overload installation box 5 as a whole will include a heat dissipation cap 54 and an insulating isolation cap 55. The heat dissipation film is made of metal material. The cap groove of the heat dissipation cap 54 is provided for the connection active rod 6. The bottom of the cap groove of the heat dissipation cap 54 will be penetrated by the connection active rod 6 to form the aforementioned connecting hole 52. The larger surface area of ​​the heat dissipation cap 54 can be used to promote the heat dissipation of the overload installation box 5, so the ambient temperature in the area where the fuse 3 is located can be further reduced, thereby improving the ambient temperature of the fuse working, thereby achieving a compatible balance between the overload performance of the fuse and the temperature resistance performance of the application environment; the cap groove of the insulating isolation cap 55 is provided for the heat dissipation cap 54, and the cap groove of the insulating isolation cap 55 faces the direction of the connecting solder 7. At the same time, the insulating isolation cap 55 is also located between the conductive connecting piece 4 and the heat dissipation cap 54 to play an insulating isolation role, thereby maintaining the safe use of the fuse.

[0050] Reference Figure 1 and Figure 3 In order to further promote the heat dissipation of the overload installation box 5, the structural form of the conductive connecting piece 4 will also be optimized accordingly. Specifically, the conductive connecting piece 4 is an integrally formed rectangular frame, but the conductive connecting piece 4 as a whole is divided into a conductive input ring 41, a transfer piece 42 and a collecting piece 43 according to its function. The conductive input ring 41 is coaxially sleeved on the end of the connecting rod 6 outside the installation cavity 51. At the same time, before the connecting solder 7 is melted, the inner side of the conductive input ring 41 is in contact with the connecting rod 6 to realize the guide barrel between the conductive connecting piece 4 and the connecting rod 6; there are two transfer pieces 42, one end of the two transfer pieces 42 is connected to the conductive input ring 41, and the other end extends in the direction away from the connecting solder 7, wherein the two transfer pieces 42 are symmetrically arranged relative to the center of the conductive input ring 41, and the area between the two transfer pieces 42 is just for the overload installation box 5 to be set.

[0051] Reference Figure 1 and Figure 3 Two collecting pieces 43 are also provided. The ends of the two collecting pieces 43 away from each other are respectively connected to the ends of the two transfer pieces 42 away from the conductive input ring 41. The ends of the two collecting pieces 43 close to each other are connected together as a whole, so that the conductive connecting piece 4 forms a rectangular frame shape. At the same time, the ends of the two collecting pieces 43 close to each other are also connected to the fuse 3 away from the connecting solder 7. In summary, after leaving the guide barrel input ring, the current will be divided into two branches for transmission, so the heat transmitted to the overload installation box 5 will also be more uniform, so as to promote the heat dissipation of the overload installation box 5.

[0052] At the same time, in this embodiment, the overload installation box 5 will also abut against the inner side of the conductive connecting piece 4, so the conductive connecting piece 4 can be used to achieve fixed installation of the overload installation box 5, thereby making the structural form of the overload fuse structure more compact and simpler.

[0053] Reference Figure 1 and Figure 3 In this embodiment, a sealing solder 10 is formed on the side of the conductive input ring 41 away from the overload installation box 5 through welding. The sealing solder 10 is connected to the outer wall of the peripheral side of the connecting rod 6 to block the area between the peripheral side of the connecting rod 6 and the inner wall of the connecting hole 52. Therefore, in the process of filling the arc extinguishing sand 9 into the arc extinguishing cavity 11, the arc extinguishing sand 9 will not enter the installation cavity 51, thereby maintaining the normal implementation of the subsequent arc extinguishing operation.

[0054] The implementation principle of a high-breaking-power fuse in an embodiment of the present application is as follows: after the connecting solder 7 is melted, the disconnecting spring 8 will use its own elastic force to retract the connecting rod 6 into the installation cavity 51. At the same time, the arc-extinguishing sand 9 that was originally in an overpressure state will be pressure-released and quickly enter the arc-extinguishing filling cavity, so that the gap between the connecting rod 6 and the fuse 3 can be completely filled, and at the same time, the retraction movement of the connecting rod 6 will not be hindered, thereby forming a complete isolation effect on the connecting rod 6 and the fuse 3, which in turn helps to improve the arc-extinguishing performance of the fuse.

[0055] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A high breaking capacity fuse, characterized by: include: Protective tube (1); Touch blades (2) are sealingly arranged on both ends of the protection tube (1) and are used to form an arc extinguishing cavity (11) inside the protection tube (1); A fuse (3) is arranged in the arc extinguishing chamber (11); A conductive connecting piece (4) is provided at a disconnection point between the circuit where the fuse (3) and the contact blade (2) are located; An overload installation box (5) is arranged in the arc extinguishing chamber (11), and the overload installation box (5) is provided with an installation chamber (51) and a communication hole (52); A connecting rod (6) has one end disposed in the installation cavity (51) and the other end sliding in and out of the communication hole (52); an arc extinguishing filling area (53) communicating with the communication hole (52) is formed between the installation cavity (51) and the connecting rod (6); A connecting solder (7) is provided between the fuse (3) and one end of the connecting rod (6) outside the mounting cavity (51), and is used to connect the disconnected portion of the circuit where the fuse (3) and the contact blade (2) are located; A breaking spring (8) connected to the connecting rod (6) and used to retract the connecting rod (6) into the installation cavity (51); Arc extinguishing sand (9) is filled in the arc extinguishing chamber (11) under overpressure.

2. The high breaking capacity fuse according to claim 1, characterized in that: The connecting rod (6) has a frustum shape at one end close to the connecting solder (7); the smaller the cross-sectional area of ​​the connecting rod (6), the closer the end is to the connecting solder (7).

3. The high breaking capacity fuse according to claim 2, characterized in that: The arc extinguishing sand (9) is made of quartz sand.

4. The high breaking capacity fuse according to claim 3, characterized in that: A force ring (61) is sleeved on one end of the connecting rod (6) away from the connecting solder (7); the disconnecting spring (8) is located in the mounting cavity (51), the disconnecting spring (8) is sleeved on the connecting rod (6), and the disconnecting spring (8) and the force ring (61) are in contact with the surface of the connecting solder (7).

5. The high breaking capacity fuse according to claim 1, characterized in that: Two fuses (3) are provided, and the overload installation box (5) is provided at a discontinuity between the two fuses (3), so as to enable the overload installation box (5) to be located in the middle position between the two contact blades (2); one end of the conductive connecting piece (4) is connected to the end of the connecting rod (6) outside the installation cavity (51), and the other end is connected to the fuse (3) away from the connecting solder (7).

6. The high breaking capacity fuse according to claim 5, characterized in that: The overload installation box (5) includes a heat dissipation cap (54) and an insulating isolation cap (55). The heat dissipation cap (54) is made of metal. The cap groove of the heat dissipation cap (54) is provided for the connection active rod (6). The bottom of the cap groove of the heat dissipation cap (54) is provided for the connection active rod (6) to pass through to form the connecting hole (52). The cap groove of the insulating isolation cap (55) is provided for the heat dissipation cap (54). The cap groove opening of the insulating isolation cap (55) faces the direction where the connection solder (7) is located. The insulating isolation cap (55) is located between the conductive connecting piece (4) and the heat dissipation cap (54).

7. The high breaking capacity fuse according to claim 6, characterized in that: The conductive connecting piece (4) is divided into a conductive input ring (41), a transfer piece (42) and a collecting piece (43). The conductive input ring (41) is sleeved on the end of the connecting rod (6) outside the installation cavity (51); one end of the transfer piece (42) is connected to the conductive input ring (41), and the other end extends in a direction away from the connecting solder (7). Two transfer pieces (42) are symmetrically arranged relative to the center of the conductive input ring (41), and the area between the two transfer pieces (42) is used to accommodate the overload installation box (5); two collecting pieces (43) are arranged, and the ends of the two collecting pieces (43) close to each other are connected to the ends of the transfer piece (42) away from the conductive input ring (41), and the ends away from each other are connected to the fuse (3).

8. The high breaking capacity fuse according to claim 7, characterized in that: The conductive connection is integrally formed into a rectangular frame shape, the overload installation box (5) is located on the inner side of the conductive connection piece (4), and the overload installation box (5) abuts against the inner side of the conductive connection piece (4).

9. The high breaking capacity fuse according to claim 7, characterized in that: A sealing solder (10) is provided on the side of the conduction input ring (41) away from the overload installation box (5), and the sealing solder (10) is connected to the outer wall of the connecting rod (6) to seal and block the communication hole (52).

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