Excitation type fuse

Abstract

The utility model discloses an excitation type fuse, which comprises an upper shell, a lower shell, a conductive part and a trigger device, and is characterized in that the lower shell is provided with a lower accommodating cavity, an arc extinguishing part and a buffer part; the conductive part is arranged between the upper shell and the lower shell; before the trigger device is started, the conductive part is conductive; the conductive part is provided with a middle section and conductive sections arranged on the two sides, and the buffer part is used for bearing the middle section, is arranged in the lower accommodating cavity and is positioned below the middle section; the arc extinguishing part is arranged around the buffer part and is used for absorbing the generated arc; the trigger device is arranged on the upper shell, is used for driving the middle section to be separated from the conductive sections on the two sides, and is also used for driving the middle section to move towards the lower accommodating cavity and impact the buffer part; if the trigger device is started, the middle section is located in the lower containing cavity, the buffer part is extruded and deformed, and the excitation type fuse has better explosion-proof and insulation safety.

Description

Technical Field

[0001] The utility model relates to the field of power control and circuit protection, in particular to an excitation type fuse. Background Art

[0002] Traditional fuses are the fragile parts of circuits or electrical appliances. Once a fault occurs in the circuit (such as overload current), the traditional fuse will blow and disconnect the circuit in time. In the field of new energy and wind and solar energy storage, when the system detects circuit anomalies (such as battery failure, overcharging, current anomalies) and environmental anomalies (such as natural disasters, extreme temperatures, immersion in water), the system needs the fuse to actively and quickly cut off the circuit to ensure the safety of personnel and equipment. Obviously, traditional fuses cannot meet the above requirements, and incentive fuses came into being.

[0003] The current excitation-type fuses mechanically cut off the circuit quickly with a power source such as gunpowder after receiving the system's cut-off command. How to quickly and stably cut off the circuit and ensure insulation safety after cutting is one of the technical difficulties; how to solve the arcing (or arc extinguishing solution) of the high-voltage break and improve the explosion-proof safety of the device is the second technical difficulty.

[0004] A circuit switching device in the prior art has an arc extinguishing area filled with cooling material. The cooling material needs to have the dual functions of arc extinguishing and buffering. It is difficult to balance the volume required for arc extinguishing and the height required for buffering, so the arc extinguishing area occupies a large size. The device uses cooling material to cover the cut surface of the conductive sheet to capture energy and extinguish the arc. In order to more fully cool and cover, a more sufficient gap is required between the cooling materials. The device simply lays the cooling material in the arc extinguishing area, and there is no design to accommodate the conductor sheet after the impact. At the same time, there is a risk that the cooling material will be squeezed and exposed in the opposite direction after being impacted, making it difficult to ensure insulation safety after work. Utility Model Content

[0005] The utility model aims to provide a new excitation type fuse.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: an excitation type fuse, comprising:

[0007] Upper shell,

[0008] A lower housing having a lower accommodating chamber;

[0009] A conductive part is arranged between the upper shell and the lower shell; before the trigger device is activated, the conductive part is configured to be conductive; the conductive part has a middle section and conductive sections arranged on both sides of the middle section, and an arc extinguishing part and a buffer part are arranged in the lower shell, wherein:

[0010] The buffer portion configured to receive the middle section is disposed in the lower accommodation cavity and below the middle section;

[0011] The arc extinguishing part is a wire mesh made of a conductive metal with a porous structure, the arc extinguishing part is arranged around the buffer part, and the wire mesh is used to absorb the generated arc;

[0012] A trigger device is arranged on the upper shell; the trigger device is used to cut off the two sides of the middle section so as to separate the middle section from the conductive sections on both sides, and the trigger device is also used to drive the middle section to move toward the lower accommodating cavity and impact the buffer portion; if the trigger device is activated, the middle section is located in the lower accommodating cavity, and the buffer portion is squeezed and deformed.

[0013] The excitation type fuse provided by the present invention has the conductive part realizing normal conduction of the circuit before the trigger device is triggered; when an accident occurs and the circuit needs to be cut off, the trigger device is activated, at which time the middle section moves downward into the accommodating cavity and impacts the buffer part, which receives the middle section and offsets the impact energy of the middle section by deformation. During this process, the wire mesh absorbs the generated arc to ensure the explosion-proof performance of the excitation type fuse.

[0014] In some embodiments, the lower shell has an installation cavity arranged in a ring around the outside of the lower accommodating cavity, the wire mesh is arranged in the installation cavity, and a plurality of limit plates are arranged at intervals between the installation cavity and the lower accommodating cavity. The plurality of limit plates are arranged in a ring around the circumference of the lower accommodating cavity and are used to limit the displacement of the wire mesh. An opening is provided between two adjacent limit plates, and the opening connects the lower accommodating cavity and the installation cavity. The wire mesh has a protrusion extending from the opening into the lower accommodating cavity, and during the downward impact of the middle section, the protrusion absorbs the generated arc from the side.

[0015] In some embodiments, the upper portion of the buffer portion has a plurality of avoidance grooves spaced apart along the circumferential direction, and the protrusion is inserted into the avoidance grooves. The protrusion cooperates with the avoidance grooves to limit the rotation of the buffer portion, so that the buffer portion can more stably receive the middle section, and the setting of the avoidance grooves prevents the buffer portion from blocking the protrusion, thereby ensuring the normal arc extinguishing operation.

[0016] In some embodiments, the excitation type fuse includes a support section fixedly connected to the lower shell, the support section is located between the middle section and the buffer portion, the support section is fixedly connected to the lower shell via a connecting rib, a plurality of the connecting ribs are arranged at intervals, a through hole communicating with the lower accommodating cavity is provided between two adjacent connecting ribs, the through hole is located above the protruding portion, and the projection of the protruding portion in the up-down direction is located within the projection of the through hole in the up-down direction. The arc generated by the cutting of the conductive portion can be absorbed by the protruding portion through the through hole.

[0017] In some embodiments, there are four limit plates, and a reinforcing rib is provided between each limit plate and the side wall of the lower shell. The four reinforcing ribs divide the installation cavity into four chambers, and each chamber is provided with a wire mesh, and each wire mesh has a protrusion. There are four connecting ribs, and four through holes are formed between the four connecting ribs, and the four through holes are respectively located above the four protrusions. The reinforcing ribs increase the strength of the limit plates, and the four protrusions are distributed at intervals on the circumference of the lower accommodating cavity, which can absorb the generated arc from multiple directions and improve the arc extinguishing effect. The four through holes facilitate the four protrusions to strike the arc.

[0018] In some embodiments, the side wall of the lower shell is provided with a protrusion, the protrusion abuts against the wire mesh, and the protrusion is configured to drive the wire mesh to extend from the opening into the lower accommodating cavity. The provision of the protrusion improves the firmness of the wire mesh fixed in the accommodating cavity, and the protrusion can drive the wire mesh to extend into the lower accommodating cavity, thereby forming the above-mentioned protrusion.

[0019] In some embodiments, it also includes a support section fixedly connected to the lower shell, the support section is located between the middle section and the buffer; the trigger device is also used to separate the support section from the lower shell and displace it toward the lower accommodating cavity and impact the buffer; if the trigger device is activated, the support section is separated from the lower shell, the support section is located in the lower accommodating cavity and abuts against the buffer. The support section can not only support the middle section, but also absorb the energy of the middle section's downward impact.

[0020] In some embodiments, a limiting column is further provided on the side of the support section facing the buffer portion, the limiting column is inserted into the hollow cavity of the buffer portion, and the end of the limiting column away from the support section is a free end; before the trigger device is activated, the free end is suspended in the accommodating cavity; if the trigger device is activated and the free end abuts against the lower shell and / or the buffer portion, the middle section stops moving toward the lower accommodating cavity. The limiting column can prevent the support section from moving downward, thereby preventing the middle section from moving downward.

[0021] In some embodiments, the bottom wall of the lower shell is provided with a limit groove extending downward, the limit groove is located below the buffer portion and communicates with the hollow cavity of the buffer portion, the bottom wall of the limit groove is lower than the lower portion of the buffer portion, if the trigger device is activated and the free end abuts against the bottom wall of the limit groove, the middle section stops moving toward the lower accommodating cavity. The limit groove limits the maximum distance of the support section and the middle section moving downward.

[0022] In some embodiments, the buffer portion includes a first column and a second column, the first column has a receiving cavity, the size of the upper portion of the receiving cavity is larger than the size of the middle section, and the size of the lower portion of the receiving cavity is smaller than the size of the middle section, so as to receive the middle section when the trigger device is activated; the second column is fixedly arranged at the lower portion of the first column, if the trigger device is activated, the middle section is received in the receiving cavity, and the second column is squeezed and deformed; and / or, a plurality of perforations are arranged on the circumference of the second column. The receiving cavity is used to receive the middle section, so as to ensure the insulation safety of the excitation type fuse, and the setting direction of being wide at the top and narrow at the bottom is also convenient for receiving the middle section, and the second column can offset the impact energy by deformation.

[0023] In some embodiments, the lower shell includes a first lower shell and a second lower shell, the second lower shell is located below the first lower shell, and the lower portion of the buffer portion is snap-connected to the second lower shell, which facilitates installation of the buffer portion and improves stability of the buffer portion.

[0024] In some embodiments, the excitation type fuse further includes a pre-positioning mechanism to position the conductive part, and the pre-positioning mechanism includes two groups; the pre-positioning mechanism includes a first pre-positioning part arranged on the lower shell, and the conductive part is provided with a second pre-positioning part matched with the first pre-positioning part; and / or, the first pre-positioning part is a positioning column, and the second pre-positioning part is a hole opened on the conductive part and adapted to the positioning column. Preferably, the two groups of pre-positioning mechanisms are eccentrically arranged to achieve a foolproof function.

[0025] In some embodiments, the bottom wall of the lower shell is also provided with an air flow channel connected to the outside, and the air flow channel includes a groove and at least one pressure relief port; the groove is located at a corresponding position of the lower accommodating cavity, and the pressure relief port is located at a corresponding position of the side wall of the lower shell; the pressure relief port and the groove are not in the same plane to prevent the arc from leaking through the air flow channel.

[0026] Due to the application of the above technical scheme, the utility model has the following advantages compared with the prior art: the excitation type fuse of the utility model, after the trigger device is activated, the buffer portion arranged in the lower accommodating cavity can receive the middle section and offset the energy of the downward impact of the middle section through deformation, and the arc extinguishing portion arranged around the buffer portion can absorb the generated arc to achieve the arc extinguishing effect, thereby improving the safety performance of the excitation type fuse. At the same time, the insulation safety of the excitation type fuse is ensured by the buffer portion receiving the middle section. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Attached Figure 1 It is a three-dimensional structural schematic diagram of an excitation type fuse according to a specific embodiment of the utility model;

[0028] Attached Figure 2 For attachment Figure 1 Side view of

[0029] Attached Figure 3 For the attachment Figure 2 Sectional view along AA direction;

[0030] Attached Figure 4 For attachment Figure 3 Schematic diagram after the trigger device is activated;

[0031] Attached Figure 5 For the attachment Figure 2 Cross-sectional view along the BB direction;

[0032] Attached Figure 6 is a three-dimensional schematic diagram of the lower housing of this embodiment;

[0033] Attached Figure 7 For attachment Figure 6 A three-dimensional schematic diagram of the first lower shell;

[0034] Attached Figure 8 For attachment Figure 7 Bottom view of

[0035] Attached Fig. 9 For the attachment Figure 8 Schematic diagram after CC section and flipping upside down;

[0036] Attached Fig.10 For attachment Figure 1 A three-dimensional schematic diagram of the structure of the middle part;

[0037] Attached Fig.11 For attachment Fig.10 A three-dimensional schematic diagram of the second lower shell;

[0038] Attached Fig.12 For attachment Fig.11 Schematic diagram of longitudinal section;

[0039] Attached Fig.13 is a schematic diagram of the three-dimensional structure of the buffer portion of this embodiment;

[0040] Attached Fig.14 is a schematic diagram of the three-dimensional structure of the conductive part of this embodiment;

[0041] Among them: 1, upper shell; 2, lower shell; 20, slot; 201, first cavity; 202, second cavity; 2a, first lower shell; 2b, second lower shell; 21, lower accommodating cavity; 22, installation cavity; 23, limit plate; 231, opening; 24, reinforcing rib; 25, protrusion; 26, limit groove; 27, positioning column; 28, air flow channel; 281, groove; 282, pressure relief port; 29, accommodating groove; 291, reinforcing rib; 3, extinguisher Arc portion; 31, protruding portion; 4, buffer portion; 41, first column; 411, receiving cavity; 412, avoidance groove; 42, second column; 421, perforation; 5, trigger device; 51, power unit; 511, limiting surface; 52, firing unit; 521, sealing ring; 6, conductive portion; 61, middle section; 62, conductive section; 621, positioning hole; 63, incision; 71, supporting section; 72, limiting column; 73, connecting rib; 74, through hole. DETAILED DESCRIPTION

[0042] The technical solution of the utility model is described in detail below in conjunction with the accompanying drawings and specific embodiments, so that the advantages and features of the utility model can be more easily understood by those skilled in the art. Obviously, the embodiments described in this application are only part of the embodiments of the application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of this application.

[0043] See also Figures 1 to 4 An excitation type fuse is shown, which includes an upper shell 1, a lower shell 2, a trigger device 5 and a conductive part 6. The lower shell 2 has a lower accommodating chamber 21; the conductive part 6 is arranged between the upper shell 1 and the lower shell 2, and has a middle section 61 and conductive sections 62 arranged on both sides of the middle section 61; the trigger device 5 is arranged on the upper shell 1, and is used to cut off the two sides of the middle section 61 so as to separate the middle section 61 from the conductive sections 62 on both sides. Before the trigger device 5 is activated, the middle section 61 is connected to the conductive sections 62 on both sides, and the conductive part 6 can conduct electricity, so that the circuit is turned on. After the trigger device 5 is activated, the middle section 61 is separated from the conductive sections 62 on both sides, and the middle section 61 is located in the lower accommodating chamber 21, and the conductive part 6 loses its conductive function, so that the circuit is cut off.

[0044] The lower housing 2 is provided with an arc extinguishing portion 3 and a buffer portion 4, wherein the buffer portion 4 is used to receive the middle section 61, and the buffer portion 4 is arranged in the lower accommodating chamber 21 and is located below the middle section 61. If the trigger device 5 is activated, the trigger device 5 drives the middle section 61 to move toward the lower accommodating chamber 21 and impact the buffer portion 4, and the buffer portion 4 is squeezed and deformed, thereby decelerating the middle section 61. The arc extinguishing portion 3 is arranged around the buffer portion 4, and the arc extinguishing portion 3 is a wire mesh made of a conductive metal with a porous structure, and the wire mesh is used to absorb the generated arc.

[0045] In this embodiment, a notch 63 extending upward is formed on the lower surface of the connection between the middle section 61 and the conductive section 62. When the trigger device 5 impacts the middle section 61 downward, the notch 63 is broken, so that the middle section 61 is separated from the conductive section 62. In this embodiment, the notch 63 is in a V-shape with the mouth facing downward. In other embodiments, the notch 63 is provided on both the upper and lower surfaces of the conductive part 6 so that the trigger device 5 can break the conductive part 6. The notch 63 can also be set to other shapes that are convenient for breaking.

[0046] In this embodiment, the trigger device 5 includes a power unit 51 and a firing unit 52. The power unit 51 is arranged above the firing unit 52, and the firing unit 52 is arranged above the conductive unit 6. Specifically, the firing unit 52 is arranged above the middle section 61. The power unit 51 is used to drive the firing unit 52 to move downward, and the firing unit 52 is used to impact the middle section 61 and break the conductive unit 6. In this embodiment, the middle section 61 is circular, and the cross section of the firing unit 52 is also circular. The diameter of the firing unit 52 is slightly smaller than the diameter of the middle section 61, so that the middle section 61 can be broken from the conductive section 62 and the middle section 61 can be driven to move downward.

[0047] In this embodiment, the power unit 51 is arranged at the upper part of the upper shell 1, and the firing unit 52 is arranged at the lower part of the upper shell 1. Figure 3 , Figure 4 As shown, the upper shell 1 has a first cavity 201 and a second cavity 202 which are interconnected, the first cavity 201 is located above the second cavity 202, the power part 51 is fixed in the first cavity 201, and the firing part 52 is arranged in the second cavity 202. In this embodiment, the power part 51 is a gas generating device for generating gas, and when the trigger device 5 is activated, the power part 51 generates gas and pushes the firing part 52 to move downward, and during this process, the firing part 52 breaks the conductive part 6.

[0048] In this embodiment, a limiting structure is provided between the power unit 51 and the upper housing 1 to prevent the power unit 51 from rotating, so as to maintain the stability of the power unit 51, thereby ensuring that the excitation type fuse can work normally. Figure 1 , Figure 3As shown, one side of the first cavity 201 protrudes inward, and the peripheral side of the power unit 51 is provided with a limiting surface 511 that is concave inward. When the power unit 51 is fixed in the first cavity 201, the cavity wall that protrudes inward abuts against the limiting surface 511, thereby achieving a limiting effect. In this embodiment, a sealing mechanism is provided between the side wall of the firing part 52 and the side wall of the second cavity 202 to improve the airtightness, so that under the push of the gas generated by the power unit 51, the firing part 52 can quickly break the conductive part 6 and protect the circuit. Specifically, see Figure 3 As shown, an annular groove is provided on the upper portion of the firing portion 52, and the sealing structure includes a sealing ring 521 arranged in the annular groove. The sealing ring 521 is made of elastic material and can be tightly abutted against the side wall of the second cavity 202 to form a seal.

[0049] In this embodiment, the excitation type fuse further includes a pre-positioning mechanism to position the conductive part 6. Specifically, the pre-positioning mechanism includes a first pre-positioning part arranged on the lower housing 2, and a second pre-positioning part cooperating with the first pre-positioning part is arranged on the conductive part 6. Figure 6 , Fig.14 As shown, a slot 20 extending along a first direction is provided at the upper portion of the first lower shell 2a, the first pre-positioning portion is a positioning column 27 disposed in the slot 20, and the second pre-positioning portion is a positioning hole 621 provided on the conductive portion and adapted to the positioning column 27.

[0050] In this embodiment, the pre-positioning mechanism includes two groups, two positioning columns 27 are arranged on different sides of the length direction of the slot 20, and a positioning hole 621 is provided on each of the two conductive segments 62 of the conductive part 6. When the conductive part 6 is assembled between the upper shell 1 and the lower shell 2, the conductive part 6 is inserted into the slot 20, and the two positioning columns 27 are correspondingly inserted into the two positioning holes 621, so as to position the conductive part 6. In the process of the trigger device 5 impacting the middle segment 61, the pre-positioning mechanism can also limit the displacement of the conductive part 6 to ensure the insulation safety of the excitation type fuse. In this embodiment, there is a misalignment between the two positioning holes 621 along the width direction of the conductive part 6, and the two positioning columns 27 are also staggered from each other, which can play a fool-proof effect and prevent the conductive part 6 from being assembled incorrectly.

[0051] In this embodiment, the lower shell 2 has an installation cavity 22 arranged around the circumferential outer side of the lower accommodating cavity 21, the wire mesh is arranged in the installation cavity 22, and a plurality of limit plates 23 are arranged at intervals between the installation cavity 22 and the lower accommodating cavity 21. The plurality of limit plates 23 are arranged around the circumferential side of the lower accommodating cavity 21 and are used to limit the displacement of the wire mesh, thereby fixing the wire mesh. An opening 231 connecting the lower accommodating cavity 21 and the installation cavity 22 is formed between two adjacent limit plates 23, and the wire mesh has a protrusion 31 extending from the opening 231 into the lower accommodating cavity 21. When the conductive portion 6 is broken and the middle section 61 moves toward the lower accommodating cavity 21, the protrusion 31 can absorb the generated arc, thereby ensuring the explosion-proof safety of the excitation type fuse.

[0052] See also Figures 5 to 9 As shown, in this embodiment, four limit plates 23 are provided, and a reinforcing rib 24 is provided between each limit plate 23 and the side wall of the lower housing 2 to improve the stability of the limit plate 23. The four reinforcing ribs 24 divide the installation cavity 22 into four chambers, each of which is provided with a wire mesh, each of which has a protrusion 31, and the four protrusions 31 are distributed at intervals on the circumference of the lower accommodating cavity 21, which can absorb the generated arc from multiple directions and improve the arc extinguishing effect.

[0053] In this embodiment, the side wall of the lower shell 2 is provided with a protrusion 25 extending radially toward the opening 231. The protrusion 25 abuts against the wire mesh, and the protrusion 25 is used to drive the wire mesh to extend from the opening 231 into the lower accommodating cavity 21, thereby forming a protrusion 31. Specifically, before being assembled into the installation cavity 22, the wire mesh is in a rectangular block shape, and the wire mesh can be deformed. During the process of assembling the wire mesh into the installation cavity 22, the wire mesh matches the shape of the installation cavity 22 and is transformed into a ring shape. Driven by the protrusion 25, the middle part of the wire mesh extends into the lower accommodating cavity 21 and forms the protrusion 31. See Figure 5 , Fig.10 As shown, the wire mesh assembled into the installation cavity 22 is roughly M-shaped. With such an arrangement, the protrusion 25 can also improve the firmness of the installation of the wire mesh.

[0054] In this embodiment, the lower housing 2 includes a first lower housing 2a and a second lower housing 2b, the second lower housing 2b is located below the first lower housing 2a, and the lower accommodating cavity 21 is formed between the first lower housing 2a and the second lower housing 2b. The second lower housing 2b is detachably connected to the first lower housing 2a. When installing the arc extinguishing part 3, the second lower housing 2b needs to be detached from the first lower housing 2a, and the wire mesh needs to be inserted from the lower part of the first lower housing 2a into the installation cavity 22.

[0055] In this embodiment, the upper part of the buffer portion 4 has a plurality of avoidance grooves 412 distributed at intervals along the circumferential direction, and the protrusion 31 is inserted into the avoidance grooves 412. The cooperation between the protrusion 31 and the avoidance grooves 412 can limit the rotation of the buffer portion 4, so that the buffer portion 4 can more stably receive the middle section 61 and absorb the impact energy generated by the middle section 61 through deformation in the up and down directions. By providing the avoidance grooves 412, it is also possible to prevent the buffer portion 4 from blocking the arc extinguishing portion 3, so that the protrusion 31 can absorb the arc during the downward impact of the middle section 61.

[0056] In this embodiment, the buffer portion 4 has a receiving cavity 411. When the trigger device 5 is activated, the middle section 61 can be received in the receiving cavity 411, thereby ensuring the insulation safety of the excitation type fuse. In this embodiment, the buffer portion 4 is a cylindrical thin-walled structure, which includes a first column 41 and a second column 42. The first column 41 has a receiving cavity 411. The size of the upper part of the receiving cavity 411 is larger than the size of the middle section 61, and the size of the lower part of the receiving cavity 411 is smaller than the size of the middle section 61. The second column 42 is fixedly arranged at the lower part of the first column 41. Figure 4 , Fig.13 As shown, the first column 41 is in a trumpet shape that is wide at the top and narrow at the bottom. In other embodiments, the first column 41 can be configured to be stepped.

[0057] By providing a receiving cavity 411 that is wide at the top and narrow at the bottom, when the trigger device 5 is activated, the middle section 61 can enter the receiving cavity 411 from the top, and under the restriction of the lower part of the receiving cavity 411, the middle section 61 can be received in the receiving cavity 411. As the middle section 61 continues to move downward, the second column 42 is deformed to offset the impact force. In this embodiment, the second column 42 is provided with a weak structure so that the second column 42 can be deformed and offset the impact force. For details, see Fig.13 As shown, the weak structure is provided with a plurality of perforations 421 on the circumference of the second column 42, and the perforations 421 also connect the interior of the buffer 4 with the lower accommodating chamber 21, so that the energy and gas of the downward impact can be released outward to prevent the buffer 4 from bursting. In this embodiment, the perforations 421 are straight grooves, and in other embodiments, the perforations 421 are circular holes, or the weak structure is a mesh structure provided on the circumference of the second column 42.

[0058] In this embodiment, the excitation type fuse also includes a support section 71 fixedly connected to the lower housing 2, and the support section 71 is located between the middle section 61 and the buffer portion 4. Before the trigger device 5 is activated, the support section 71 is supported below the middle section 61. If the trigger device 5 is activated, the middle section 61 is driven by the trigger device 5 to impact the support section 71 downward, and the support section 71 is separated from the lower housing 2, and the support section 71 and the middle section 61 are displaced toward the lower accommodating cavity 21 and impact the buffer portion 4. The support section 71 can not only play the role of supporting the middle section 61, but also absorb the energy of the middle section 61 impacting downward. In this embodiment, the support section 71 is also circular. In some preferred embodiments, the size of the support section 71 is also smaller than the size of the upper part of the accommodating cavity 411, and smaller than the size of the lower part of the accommodating cavity 411, so that the support section 71 can be accommodated in the accommodating cavity 411 together with the middle section 61.

[0059] In this embodiment, the support section 71 is fixedly connected to the lower housing 2 via a connecting rib 73. A plurality of connecting ribs 73 are arranged at intervals, and a through hole 74 communicating with the lower accommodating cavity 21 is provided between two adjacent connecting ribs 73. Figure 3 , Figure 8 As shown, in this embodiment, the through hole 74 is located above the protrusion 31, so that the support section 71 will not collide with the protrusion 31 when moving downward, and the arc can be absorbed by the protrusion 31 through the through hole 74 before the middle section 61 impacts the buffer portion 4. In this embodiment, four connecting ribs 73 are provided, and four through holes 74 are formed between the four connecting ribs 73. The four through holes 74 are respectively located above the four protrusions 31.

[0060] In this embodiment, a limiting column 72 is further provided on the side of the support section 71 facing the buffer portion 4. The limiting column 72 is arranged in the hollow cavity of the buffer portion 4. The limiting column 72 prevents the support section 71 and the middle section 61 from moving downward, limits the distance of the middle section 61 moving downward, and prevents the middle section 61 from continuously impacting downward and causing damage to the interior of the lower accommodating chamber 21. Specifically, the end of the limiting column 72 away from the support section 71 is a free end. Before the trigger device 5 is activated, the free end is suspended in the lower accommodating chamber 21. If the trigger device 5 is activated, the limiting column 72 moves downward with the support section 71. When the free end abuts against the lower shell 2, the middle section 61 stops moving toward the lower accommodating chamber 21, or when the free end abuts against the buffer portion 4, the middle section 61 stops moving toward the lower accommodating chamber 21.

[0061] In this embodiment, the bottom wall of the lower shell 2 is provided with a limit groove 26 extending downward, the limit groove 26 is located below the buffer portion 4 and below the limit column 72, the limit groove 26 is connected to the hollow cavity of the buffer portion 4, and if the free end abuts against the bottom wall of the limit groove 26, the middle section 61 stops moving toward the lower accommodating cavity 21. The limit groove 26 limits the maximum distance of the support section 71 and the middle section 61 moving downward.

[0062] In this embodiment, the lower portion of the buffer portion 4 is clamped on the second lower housing 2b. Figure 3 , Fig.11 As shown, the limiting groove 26 is arranged on the second lower shell body 2 b , the groove wall of the limiting groove 26 protrudes and extends upward, and the lower part of the buffer part 4 is clamped on the groove wall of the limiting groove 26 protruding upward.

[0063] In this embodiment, see Fig.11 , Fig.12 As shown, a downwardly recessed receiving groove 29 is provided in the middle of the second lower housing 2b, and the limiting groove 26 is located at the center of the receiving groove 29. The lower part of the buffer portion 4 is inserted into the receiving groove 29. Specifically, a plurality of reinforcing ribs 291 are provided in the receiving groove 29 to improve the impact resistance. The reinforcing ribs 291 are distributed around the limiting groove 26, and the lower part of the buffer portion 4 abuts against the reinforcing ribs 291.

[0064] In this embodiment, the bottom wall of the lower housing 2 is further provided with an airflow channel 28 communicating with the outside, the airflow channel 28 includes a groove 281 and at least one pressure relief port 282, the groove 281 is located at a corresponding position of the lower accommodating chamber 21, and the pressure relief port 282 is located at a corresponding position of the side wall of the lower housing 2. The provision of the airflow channel 28 improves the exhaust performance of the excitation type fuse under instantaneous high pressure, and ensures the safety performance of the excitation type fuse.

[0065] See also Fig.11 , Fig.12 As shown, the air flow channel 28 is arranged on the second lower shell 2b, and the groove 281 is arranged around the outside of the accommodating groove 29 and the outside of the buffer portion 4, see Fig.10 As shown, the groove 281 is located below the arc extinguishing portion 3, and the pressure relief port 282 includes four pressure relief ports 282 spaced apart along the circumference of the groove 281. The four pressure relief ports 282 are all located on the outside of the groove 28. The pressure relief ports 282 connect the groove 281 with the outside of the lower shell 2. The gas can enter the pressure relief port 282 from the groove 281 and finally be discharged to the outside of the lower shell 2.

[0066] In this embodiment, the pressure relief port 282 and the groove 281 are not in the same plane. Specifically, along the vertical direction, the groove 281 is shallower than the pressure relief port 282, and the bottom of the pressure relief port 282 is lower than the bottom of the groove 281, so that a step surface is formed between the pressure relief port 282 and the groove 281. When the first lower shell 2a is fixedly connected to the second lower shell 2b, the bottom of the outer wall of the first lower shell 2a is lower than the bottom of the groove 281, but the bottom of the pressure relief port 282 is lower than the bottom of the outer wall of the first lower shell 2a. In this way, between the first lower shell 2a and the second lower shell 2b, the airflow channel 28 extends in a Z-shaped trajectory, so that the outer wall of the first lower shell 2a can prevent the arc in the lower accommodating chamber 21 from leaking outward, thereby ensuring the safety of external equipment. At the same time, the outer wall of the first lower shell 2a does not affect the passage of gas, ensuring the normal exhaust function.

[0067] In summary, the working principle of the excitation type fuse of this embodiment is: the power part 51 generates gas after being triggered, and the gas pushes the firing part 52 to move toward the lower accommodating cavity 21. During this process, the firing part 52 impacts the conductive part 6, so that the connection between the middle section 61 and the conductive section 62 is broken, and driven by the firing part 52, the middle section 61 is displaced toward the lower accommodating cavity 21, and the generated arc is absorbed by the arc extinguishing part 3 through the through hole 74.

[0068] During the downward movement of the middle section 61, the middle section 61 first impacts the support section 71, causing the connecting rib 73 to break. The support section 71 moves downward together with the middle section 61, and the support section 71 offsets a portion of the energy of the middle section 61 impacting downward. Afterwards, the support section 71 impacts the buffer section 4 downward together with the middle section 61. Before impacting the buffer section 4, the protrusion 31 can absorb the generated arc. The receiving cavity 411 of the buffer section 4 can receive the middle section 61 and the support section 71, and the buffer section 4 can offset the impact energy of the middle section 61 by deformation. Specifically, the middle section 61 and the support section 71 enter and are received in the receiving cavity 411 of the first column 41, and the second column 42 is squeezed and deformed, thereby offsetting the energy caused by the impact. During the impact of the buffer section 4, the protrusion 31 absorbs the arc.

[0069] If all the impact energy of the middle section 61 is absorbed by the buffer part 4, the middle section 61 stops moving downward. Since the impact of the middle section 61 is not directly transmitted to the second lower shell 2b, the explosion-proof performance of the excitation type fuse is improved, and the middle section 61 is accommodated in the accommodating cavity 411, ensuring the insulation safety of the excitation type fuse.

[0070] The limiting column 72 can also prevent the middle section 61 from moving downward. When the limiting column 72 abuts against the buffer 4, it limits the movement of the middle section 61 by limiting the support section 71 from continuing to move downward. In this case, the impact energy is still transmitted to the buffer 4, but not directly to the second lower shell 2b, thereby ensuring the explosion-proof performance of the excitation type fuse. Alternatively, when the free end of the limiting column 72 abuts against the limiting groove 26 on the second lower shell 2b, it can also limit the movement of the middle section 61. The reinforcing ribs 291 located on the side of the limiting groove 26 improve the impact resistance of the second lower shell 2b, thereby ensuring the explosion-proof performance of the excitation type fuse.

[0071] During the downward impact of the middle section 61, the downward compressed gas will blow the arc downward to the airflow channel 28 from top to bottom, and the protrusions 31 distributed on the side of the lower accommodating chamber 21 will capture and absorb the arc, thereby extinguishing the arc. The arc blown to the bottom will also be captured by the bottom surface of the wire mesh, further ensuring the reliability of the arc extinguishing.

[0072] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. An excitation type fuse, comprising: Upper shell, A lower housing having a lower accommodating chamber; The conductive part is arranged between the upper shell and the lower shell; the conductive part has a middle section and conductive sections arranged on both sides of the middle section, characterized in that an arc extinguishing part and a buffer part are arranged in the lower shell, wherein: The buffer portion configured to receive the middle section is disposed in the lower accommodation cavity and below the middle section; The arc extinguishing part is a wire mesh made of a conductive metal with a porous structure, the arc extinguishing part is arranged around the buffer part, and the wire mesh is used to absorb the generated arc; a trigger device, which is arranged on the upper shell; the trigger device is used to cut off the two sides of the middle section so as to separate the middle section from the conductive sections on both sides, and the trigger device is also used to drive the middle section to move toward the lower accommodating cavity and impact the buffer part; Before the trigger device is activated, the conductive portion is configured to be conductive; if the trigger device is activated, the middle section is located in the lower accommodating cavity, and the buffer portion is squeezed and deformed.

2. The excitation type fuse according to claim 1, characterized in that: The lower shell body has an installation cavity arranged in a ring outside the lower accommodating cavity, the wire mesh is arranged in the installation cavity, and a plurality of limit plates are arranged at intervals between the installation cavity and the lower accommodating cavity. The plurality of limit plates are arranged in a ring around the circumference of the lower accommodating cavity and are used to limit the displacement of the wire mesh. An opening is provided between two adjacent limit plates, and the opening connects the lower accommodating cavity and the installation cavity. The wire mesh has a protrusion extending from the opening into the lower accommodating cavity.

3. The excitation type fuse according to claim 2, characterized in that: The excitation type fuse includes a support section fixedly connected to the lower shell, the support section is located between the middle section and the buffer portion, the support section is fixedly connected to the lower shell via connecting ribs, a plurality of the connecting ribs are arranged at intervals, a through hole connected to the lower accommodating cavity is provided between two adjacent connecting ribs, the through hole is located above the protruding portion, and the projection of the protruding portion along the up and down directions is located within the projection of the through hole along the up and down directions.

4. The excitation type fuse according to claim 3, characterized in that: There are four limit plates, each of which is provided with a reinforcing rib between the limit plate and the side wall of the lower shell, and the four reinforcing ribs divide the installation cavity into four chambers, each of which is provided with a wire mesh, and each wire mesh has a protruding portion. There are four connecting ribs, four through holes are formed between the four connecting ribs, and the four through holes are respectively located above the four protruding portions; The side wall of the lower shell is provided with a protrusion, the protrusion abuts against the wire mesh, and the protrusion is configured to drive the wire mesh to extend from the opening into the lower accommodating cavity to form the protrusion.

5. The excitation type fuse according to claim 2, characterized in that: The upper portion of the buffer portion has a plurality of avoidance grooves spaced apart along the circumferential direction, and the protrusions are inserted into the avoidance grooves.

6. The excitation type fuse according to claim 1, characterized in that: It also includes a supporting section fixedly connected to the lower shell, and the supporting section is located between the middle section and the buffer portion; the trigger device is also used to separate the supporting section from the lower shell and displace it toward the lower accommodating cavity and impact the buffer portion; if the trigger device is activated, the supporting section is separated from the lower shell, and the supporting section is located in the lower accommodating cavity and abuts against the buffer portion.

7. The excitation type fuse according to claim 6, characterized in that: A limiting column is also provided on the side of the support section facing the buffer portion, and the limiting column is penetrated in the hollow cavity of the buffer portion, and the end of the limiting column away from the support section is a free end; before the trigger device is activated, the free end is suspended in the accommodating cavity; if the trigger device is activated and the free end abuts against the lower shell body and / or the buffer portion, the middle section stops moving toward the lower accommodating cavity.

8. The excitation type fuse according to claim 7, characterized in that: The bottom wall of the lower shell is provided with a limit groove, which is located below the buffer portion and communicated with the hollow cavity of the buffer portion, and the bottom wall of the limit groove is lower than the lower portion of the buffer portion. If the trigger device is activated and the free end abuts against the bottom wall of the limit groove, the middle section stops moving toward the lower accommodating cavity.

9. The excitation type fuse according to claim 1, characterized in that: The buffer portion includes a first column and a second column, the first column having a receiving cavity, the size of the upper portion of the receiving cavity is larger than the size of the middle section, and the size of the lower portion of the receiving cavity is smaller than the size of the middle section, so as to receive the middle section when the trigger device is activated; The second column is fixedly mounted at the lower part of the first column. If the trigger device is activated, the middle section is received in the receiving cavity, and the second column is squeezed and deformed. And / or, a plurality of through holes are provided on the circumference of the second column; And / or, the lower shell includes a first lower shell and a second lower shell, the second lower shell is located below the first lower shell, and the lower part of the buffer portion is snap-connected to the second lower shell.

10. The excitation type fuse according to claim 1, characterized in that: The excitation type fuse also includes a pre-positioning mechanism to position the conductive part, and the pre-positioning mechanism includes two groups; the pre-positioning mechanism includes a first pre-positioning part arranged on the lower shell, and the conductive part is provided with a second pre-positioning part cooperating with the first pre-positioning part; And / or, the first pre-positioning portion is a positioning column, and the second pre-positioning portion is a hole provided on the conductive portion and adapted to the positioning column.

11. The excitation type fuse according to claim 1, characterized in that: The bottom wall of the lower shell is also provided with an air flow channel connected to the outside, and the air flow channel includes a groove and at least one pressure relief port; the groove is located at a corresponding position of the lower accommodating cavity, and the pressure relief port is located at a corresponding position of the side wall of the lower shell; the pressure relief port and the groove are not in the same plane to prevent the arc from leaking through the air flow channel.

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