EP4693361A1

EP4693361A1 - Striker pin and instantaneous circuit breaker

Info

Publication number: EP4693361A1
Application number: EP24777518.2A
Authority: EP
Inventors: Chao DAI
Original assignee: Hangzhou Superfuse Technology Co ltd
Current assignee: Hangzhou Superfuse Technology Co ltd
Priority date: 2023-03-27
Filing date: 2024-02-04
Publication date: 2026-02-11
Also published as: CN116435137A; WO2024198724A1

Abstract

A firing pin and an instantaneous circuit breaker. The firing pin comprises a sliding cylinder, side wings and an impact part. The impact part comprises at least two impact walls; the ends of the two impact walls in the same direction are connected through the side wings; the side wings are connected to the sliding cylinder, and the outer contour surface of the side wings is located on the extended surface of the outer contour surface of the sliding cylinder. The instantaneous breaker comprises the firing pin, an upper structural component, a lower structural component, an intermediate and a conducting bar; the intermediate is arranged between the upper structural component and the lower structural component; a middle cavity is inwardly arranged along the axial direction, the conducting bar and the intermediate are integrally injection-molded, and the firing pin is driven to move from top to bottom in the middle cavity.

Description

Technical Field

The present disclosure relates to the field of fuses, in particular to a firing pin and an instantaneous circuit breaker.

Background Art

Currently, traditional fuses used in new energy power systems are gradually being replaced by instantaneous circuit breakers that can quickly cut off and protect circuits. Their main operating principle involves detecting faults in the main circuit, igniting the igniter, and generating high-pressure gas to push the firing pin to cut off the conducting bar, thereby safeguarding the main circuit.
To achieve rapid cutoff of conducting bars and enhance the operational safety of instantaneous circuit breakers, manufacturers have designed various structural forms of firing pins. However, most firing pins still adopt a single-notch form, with limited exploration into multi-notch forms.
For multi-notch firing pins, increasing the number of notches typically reduces structural strength. Therefore, how to ensure both structural strength and stability during the impact process, extend the arc distance when cutting off the conducting bar and enhance arc striking capability and equipment safety is an urgent technical issue to be addressed.

Summary of the Invention

The main purpose of the present disclosure is to provide a firing pin and an instantaneous circuit breaker that address the above technical problems existing in the prior art.
To achieve the above-mentioned purpose, the first aspect of the present disclosure provides a firing pin comprising a sliding cylinder whose axial direction aligns with the overall sliding direction of the firing pin, side wings and an impact part connected to one end of the sliding cylinder; the impact part comprises at least two impact walls; the ends of the two impact walls positioned in the same direction are connected through the side wings, the side wings are connected to the sliding cylinder; the outer contour surface of the side wings is located on the extended surface of the outer contour surface of the sliding cylinder.
In one embodiment, the two sides of the side wing protrude from the impact walls.
In one embodiment, the impact walls are connected and combined with the side wings to form an impact arc striking structure, which comprises an impact end; an impact step groove is inwardly arranged at the impact end.
In one embodiment, first filling grooves are arranged on both the inner and outer surfaces of the impact wall.
In one embodiment, a sliding seal groove is arranged along the circumferential direction on the outer contour surface of the sliding cylinder, and a sliding seal ring is arranged in the sliding seal groove.
In one embodiment, a sliding guide groove is arranged along the axial direction on the outer contour surface of the side wing.
In one embodiment, the firing pin is made of high-strength plastic, with an arc-resistant layer arranged on the surface of the firing pin.
The second aspect of the present disclosure provides an instantaneous circuit breaker, comprising the firing pin in the first aspect of the present disclosure, an upper structural component, a lower structural component, an intermediate and a conducting bar. The intermediate is arranged between the upper structural component and the lower structural component. A middle cavity for accommodating the impact pin is arranged inwardly along the axial direction on one side of the intermediate for connection with the upper structural component. The conducting bar and the intermediate are integrally injection-molded with the conducting bar passing through the middle cavity. The firing pin is driven to move from top to bottom in the middle cavity to impact and cut off the conducting bar.
In one embodiment, the upper structural component comprises an upper housing, an upper cover and an igniter. The igniter is injection-molded onto the top of the upper cover and drives the firing pin to move from top to bottom in the middle cavity upon ignition.
In one embodiment, the upper structural component further comprises a shading coil. A short-circuit slot for installing the shading coil is arranged at the top of the upper cover; a lead of the igniter is led out from the short-circuit slot. The instantaneous circuit breaker includes a package state and a usage state, wherein the lead of the igniter is connected to the shading coil in the package state.
In one embodiment, a first step groove is arranged at one end of the upper cover to connect with the intermediate, and a second step groove is arranged on the top of the intermediate. When the upper cover and the intermediate are installed, the first step groove adaptively connects with the second step groove. An upper seal ring is arranged between the first step groove and the second step groove. The upper housing is arranged on the outer side of the upper cover and the intermediate, covering the joint between the upper cover and the intermediate.
In one embodiment, a fool-proofing groove is arranged on the first step groove, and a fool-proofing protrusion is arranged on the second step groove. The fool-proofing protrusion is clamped in the fool-proofing groove when the first step groove is adaptively connected with the fool-proofing groove.
In one embodiment, the lower structural component comprises a lower housing and a lower cover. An inner cavity is arranged in the lower cover within which a dividing wall is arranged to divide the inner cavity into two arc cavities. A protruding post is arranged on the dividing wall to support the conducting bar, with a post gap reserved between the two ends of the protruding post and the inner cavity for avoiding the side wings.
In one embodiment, the firing pin moves from a first position to a second position during the process of moving from top to bottom in the middle cavity, impacting and cutting off the conducting bar. When the firing pin is at the first position, the firing pin is located above the conducting bar. When the firing pin is at the second position, the conducting bar is cut off, the impact end of the firing pin is positioned inside the inner cavity, and the side wing is positioned within the post gap.
In one embodiment, a positioning column is arranged on the protruding post, and a positioning hole is provided on the conducting bar. The positioning column is inserted into the positioning hole after the intermediate and the lower structural component are installed.
In one embodiment, avoidance slots are arranged on both sides of the top of the protruding post avoiding part of the conducting bar that bends downward after cut-off.
In one embodiment, second filling grooves are arranged on two sides of the protruding post.
In one embodiment, a third step groove is arranged in the lower cover along the circumferential direction on the upper edge of the inner cavity, and a fourth step groove is arranged at one end of the immediate for connection with the lower cover. The third step groove is adaptively connected to the fourth step groove with a lower seal ring arranged between the third step groove and the fourth step groove. The lower housing is covered on the outside of the lower cover.
In one embodiment, the intermediate comprises a fixing seat, an upper boss arranged on the upper side of the fixing seat, and a lower boss arranged on the lower side of the fixing seat. The upper boss connects with the upper cover, and the lower boss connects with the lower cover. The second step groove is arranged on the top of the upper boss and a middle cavity is arranged inside the upper boss, running through the intermediate. A sliding guide rail is arranged along the axial direction in the middle cavity to fit with the sliding guide groove of the firing pin.
In one embodiment, the lower boss is inserted into the inner cavity. A fool-proofing concave section is arranged on the outer side of the lower boss, while a corresponding fool-proofing convex section is arranged in the inner cavity. The fool-proofing concave section adaptively fits with the fool-proofing convex section.
In one embodiment, a positioning groove is arranged at the bottom end of the lower boss to clamp the top of the dividing wall.
In one embodiment, two arc-crossing walls are symmetrically arranged inside the lower boss. When the firing pin cuts off the conducting bar, the arc-crossing walls and the impact wall of the firing pin are in a clearance fit.
In one embodiment, the fixing seat has a concave contact on the side facing the lower boss for fitting with the lower cover, wherein the depth of the concave contact surface is not greater than the thickness of the upper edge of the lower cover.
In one embodiment, the instantaneous circuit breaker comprises connecting screws. Threaded holes are provided on the lower edge of the upper housing, the fixing seat, the upper edge of the lower cover and the upper edge of the lower housing. The connecting screws sequentially pass through the threaded holes on the upper housing, the fixing seat, the lower cover and the lower housing to fasten the upper housing, the fixing seat, the lower cover and the lower housing into a whole.
In one embodiment, the conducting bar is provided with a breaking groove for the firing pin to cut off the conducting bar, and a bending groove is also arranged on the inner side of the breaking groove to allow downward bending after cut-off.
In one embodiment, a cavity is formed between the arc-crossing wall and the inner wall of the lower boss, and one or more notches are arranged on the arc-crossing wall.
The firing pin and the instantaneous circuit breaker disclosed in the present disclosure enhance the structural strength of the impact part through the use of the side wings, while allowing an increased number of notches in the firing pin. This design effectively ensures the stability of the firing pin during the impact process. Additionally, the side wings allow the firing pin to extend the arc distance when cutting off the conducting bar, thereby improving the arc striking capability and equipment safety.
It should be understood that the content described in this section is not intended to identify key or critical features of the embodiments of the present disclosure, nor should it be construed as limiting the scope of the present disclosure. Other features of the present disclosure will become apparent from the following detailed description.

Brief Description of the Drawings

By referring to the drawings and reviewing the following detailed description, the above and other purposes, features, and advantages of exemplary embodiments of the present disclosure will become readily comprehensible. In the drawings, some embodiments of the present disclosure are illustrated in an exemplary way rather than a restrictive way, wherein:
In the drawings, the same or corresponding reference signs indicate the same or corresponding parts.

FIG. 1 is a schematic diagram of the firing pin in one embodiment of the present disclosure.
FIG. 2 is a schematic diagram of the firing pin in another embodiment of the present disclosure.
FIG. 3 is a section view of the instantaneous circuit breaker in one embodiment of the present disclosure.
FIG. 4 is an exploded view of the instantaneous circuit breaker in one embodiment of the present disclosure.
FIG. 5 is a structural diagram of the conducting bar in one embodiment of the present disclosure.
FIG. 6 is a structural diagram of the upper cover in one embodiment of the present disclosure.
FIG. 7 is a structural diagram of the lower cover in one embodiment of the present disclosure.
FIG. 8 is a structural diagram of the intermediate in one embodiment of the present disclosure.
FIG. 9 is a structural diagram of FIG. 8 from another perspective.
FIG. 10 is a structural diagram of the intermediate in another embodiment of the present disclosure.

The above-mentioned drawings include the following reference signs:
1. Firing pin; 11. Sliding cylinder; 111. Sliding seal groove; 112. Sliding seal ring; 113. Limit surface; 12. Side wing; 121. Sliding guide groove; 122. Top groove; 13. Impact part; 131. Impact wall; 1311. First filling groove; 132. Impact end; 133. Impact step groove; 2. Upper structural component; 21. Upper housing; 211. Threaded hole; 22. Upper cover; 221. Short-circuit slot; 222. First step groove; 2221. Fool-proofing groove; 223. Upper seal ring; 23. Igniter; 24. Shading coil; 3. Lower structural component; 31. Lower housing; 32. Lower cover; 321. Inner cavity; 3211. Arc cavity; 3212. Third step groove; 3213. Fool-proofing convex section; 322. Dividing wall; 323. Protruding post; 3231. Avoidance slot; 3232. Second filling groove; 324. Post gap; 325. Positioning column; 326. Lower seal ring; 4. Intermediate; 41. Fixing seat; 411. Concave contact surface; 42. Upper boss; 421. Second step groove; 4211. Fool-proofing protrusion; 422. Middle cavity; 4221. Sliding guide rail; 43. Lower boss; 431. Fourth step groove; 432. Fool-proofing concave section; 433. Positioning groove; 434. Arc-crossing wall; 435. Cavity; 4341. Notch; 5. Conducting bar; 50. Weak section; 51. Positioning hole; 52. Breaking groove; 53. Bending groove; 54. Cushion; 6. Connecting screw; 61. Screw washer.

Detailed Description of the Invention

To clarify and illustrate the purposes, features and advantages of the present disclosure, the technical proposals in the embodiments of the present disclosure are described clearly and comprehensively with reference to the drawings. It is evident that the described embodiments are merely a part of the embodiments of the present disclosure, rather than all of them. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present disclosure.
For multi-notch firing pins, it is essential to ensure the structural strength and the stability of the impact process while increasing the number of notches.
As shown in FIG. 1 and FIG. 2, the first aspect of the present disclosure provides a firing pin 1. The firing pin 1 is made of high-strength plastic, with an arc-resistant layer arranged on its surface. The firing pin 1 comprises a sliding cylinder 11 whose axial direction is consistent with the overall sliding direction of the firing pin 1, side wings 12 and an impact part 13 connected to one end of the sliding cylinder 11. The impact part 13 comprises at least two impact walls 131, the ends of the two impact walls 131 in the same direction are connected through the side wings 12. The side wings 12 are connected to the sliding cylinder 11, and the outer contour surface of the side wings 12 is located on the extended surface of the outer contour surface of the sliding cylinder 11.
In the embodiments of the present disclosure, the impact walls 131 are connected and combined with the side wings 12 to form an impact arc striking structure, which comprises an impact end 132. An impact step groove 133 is inwardly arranged at the impact end 132. To facilitate the initial processing and testing, arc preventive materials with a certain thickness can be added to the impact step groove 133 to cut off the path of the arc passing through the arc-crossing surface of the firing pin 1.
As shown in FIG. 2, in the embodiments of the present disclosure, the two sides of the side wing 12 protrude from the impact walls 131, allowing the impact arc striking structure to form a zigzag structure. This configuration enhances the supporting strength of the impact wall 131 using the side wings 12, reducing the likelihood of damage to the side wings 12 during the impact on the conducting bar 5. Additionally, it increases the minimum arc-crossing distance, forcing any arc that could have passed through the side of the impact wall 131 to bypass the side wings 12 to complete the arc connection.
As shown in FIG. 1, in the embodiments of the present disclosure, the two sides of the side wing 12 do not protrude from the impact wall 131, allowing the impact arc striking structure to form a hollow square-shaped structure. This configuration enhances the supporting strength of the impact wall 131 through the side wings 12, making the side wings 12 less susceptible to damage during the impact on the conducting bar 5.
In the embodiments of the present disclosure, the inner and outer surfaces of the impact wall 131 serve as arc-crossing surfaces. First filling grooves 1311 are arranged on the inner and outer surfaces of the impact wall 131 to prevent the arc-resistant coating on the surface of the arc-crossing surface from being scraped off during the displacement of the firing pin 1 and allow the arc-resistant coating to better adhere to the arc-crossing surface, thereby reducing carbonization on the surface of the impact wall 131.
In the embodiments of the present disclosure, top grooves 122 are arranged at the tops of the impact end 132 and the side wing 12. The top grooves 122 improve the adhesion of the arc-resistant coating to the surface of the impact end 132 and prevent the arc from bypassing through the inner wall of the firing pin due to distance to directly pass through the top of the side wing 12, thereby increasing the arc-crossing distance.
As shown in FIG. 3 and FIG. 4, the second aspect of the present disclosure provides an instantaneous circuit breaker, comprising the firing pin 1 in the first aspect of the present disclosure, an upper structural component 2, a lower structural component 3, an intermediate 4 and a conducting bar 5. The intermediate 4 is arranged between the upper structural component 2 and the lower structural component 3. A middle cavity 422 for accommodating the impact pin 1 is arranged inwardly along the axial direction on one side so that the intermediate 4 is connected with the upper structural component 2. The conducting bar 5 and the intermediate 4 are integrally injection-molded with the conducting bar 5 passing through the middle cavity 422. The firing pin 1 moves from top to bottom in the middle cavity 422 to impact and cut off the conducting bar 5.
As shown in FIG. 3 to FIG. 5, in the embodiments of the present disclosure, a weak section 50 is arranged on one side of the conducting bar 5 facing the firing pin 1, aligned with the impact end 132, to facilitate cutting of the conducting bar 5 by the firing pin 1. A breaking groove 52 is arranged on the opposite side of the weak section 50, aiding in cutting off the conducting bar 5 and thereby improving the cut-off rate. Additionally, a bending groove 53 is arranged on the inner side of the breaking groove 52 to allow the conducting bar 5 to bend downward after being cut-off. After the conducting bar 5 is cut off, the firing pin 1 continues to move downward in the middle cavity 422. Since the impact step groove 133 is arranged inwardly at the impact end 132, the pressure at the impact end 132 is concentrated near the breaking groove 52, causing the conducting bar 5 to bend downward along the bending groove 53.
As shown in FIGS. 3, 4 and 6, the upper structural component 2 specifically comprises an upper housing 21, an upper cover 22 and an igniter 23. The igniter 23 is injection-molded onto the top of the upper cover 22 and upon ignition, drives the firing pin 1 to move from top to bottom in the middle cavity 422.
As shown in FIGS. 3 and 4, in the embodiments of the present disclosure, the upper structural component 2 further comprises a shading coil 24. A short-circuit slot 221 for installing the shading coil 24 is arranged on the top of the upper cover 22, and a lead of the igniter 23 is led out from the short-circuit slot 221. The instantaneous circuit breaker operates in two states: a package state and a usage state. In the package state, the lead of the igniter 23 is connected to the shading coil 24 to prevent explosion during transportation and enhance safety during storage and transportation. In the usage state, the lead of the igniter 23 is connected to the electrical appliance circuit, enabling the instantaneous circuit breaker to function properly and protect the electrical appliance.
In the embodiments of the present disclosure, a first step groove 222 is arranged at one end of the upper cover 22 to connect with the intermediate 4, and a second step groove 421 is arranged on the top of the intermediate 4. When the upper cover 22 and the intermediate 4 are installed, the first step groove 222 is adaptively connected with the second step groove 421 to restrict the relative displacement between the two components. An upper seal ring 223 is arranged between the first step groove 222 and the second step groove 421 to improve the connection sealing performance of the upper cover 22 and the intermediate 4. The upper housing 21, made of metal, is arranged on the outer side of the upper cover 22 and the intermediate 4, covering the joint between the upper cover 22 and the intermediate 4 to further enhance the sealing performance and increase the structural strength of the upper structural component 2.
In the embodiments of the present disclosure, a fool-proofing groove 2221 is arranged on the first step groove 222, and a fool-proofing protrusion 4211 is arranged on the second step groove 421. When the first step groove 222 is adaptively connected with the second step groove 421, the fool-proofing protrusion 4211 is clamped in the fool-proofing groove 2221, further preventing relative displacement after the upper cover 22 is connected to the intermediate 4.
As shown in FIG. 3, FIG. 4 and FIG. 7, in the embodiments of the present disclosure, the lower structural component 3 comprises a lower housing 31 and a lower cover 32. The lower cover 32 is made of high-strength plastic, and an arc-resistant layer can be plated on its surface. Threaded holes 211 are provided at four corners of the lower cover 32, with the outer side fitted to the lower housing 31 to reinforce the strength of the thin wall surface. An inner cavity 321 is arranged in the lower cover 32. A dividing wall 322 is arranged inside the inner cavity 321 and divides the inner cavity 321 into two arc cavities 3211 to prevent arc interference convection in the left and right arc cavities 3211.
In the embodiments of the present disclosure, a protruding post 323 is arranged on the dividing wall 322 to support the conducting bar 5, and the upper surface of the protruding post 323 is in contact with the middle part of the conducting bar 5 to support the conducting bar 5. A post gap 324 is reserved between the two ends of the protruding post 323 and the inner cavity 321 for avoiding the side wings 12. The firing pin 1 moves from a first position to the second position as it moves downwards in the middle cavity 422 to impact and cut off the conducting bar 5. At the first position, the firing pin 1 is situated above the conducting bar 5. When the firing pin 1 is at the second position, the conducting bar 5 is cut off, the impact end 132 of the firing pin 1 is positioned in the inner cavity 321, and the side wing 12 is located in the post gap 324.
In the embodiments of the present disclosure, a positioning column 325 is arranged on the protruding post 323, and a positioning hole 51 is provided in the conducting bar 5. After the intermediate and the lower structural component 3 are installed, the positioning column 325 is inserted into the positioning hole 51 to prevent the conducting bar 5 from shifting at the disconnected part during the breaking process.
In the embodiments of the present disclosure, avoidance slots 3231 are arranged on both sides of the top of the protruding post 323 for avoiding part of the conducting bar 5 that bends downward after being cut-off. The conducting bar cut off is bent downward into the avoidance slot 3231 to prevent obstruction or friction against the movement of the firing pin 1.
In the embodiments of the present disclosure, cushions 54 are arranged on part of the conducting bars 5 in the middle cavity 422. The surface of the sliding cylinder 11 of the firing pin 1 which connects to the impact part 13 serves as the limit surface 113. When the firing pin 1 reaches the second position, the limit surface 113 comes into contact with the cushions 54 preventing further downward movement of the firing pin 1. This arrangement buffers and releases part of the impact force, ensuring the stability of each component in the middle cavity 422.
In the embodiments of the present disclosure, second filling grooves 3232 are arranged on two sides of the protruding post 323 to prevent the surface coating of the protruding post 323 from being scraped off during the displacement of the firing pin 1. The second filling grooves 323 improve adhesion of the coating to the surface of the protruding post 323 and provide enhanced protection.
In the embodiments of the present disclosure, a third step groove 3212 is arranged in the lower cover 32 along the circumferential direction on the upper edge of the inner cavity 321. A fourth step groove 431 is arranged at one end of the immediate 4 for connection with the lower cover 32. The third step groove 3212 is adaptively connected to the fourth step groove 431 to restrict the relative displacement after the lower cover 32 is connected to the intermediate 4. A lower seal ring 326 is arranged between the third step groove 3212 and the fourth step groove 431 to improve the connection sealing performance of the lower cover 32 and the intermediate 4.
As shown in FIGS. 3, 4 and 8, in the embodiments of the present disclosure, the intermediate 4 comprises a fixing seat 41, an upper boss 42 arranged on the upper side of the fixing seat 41 and a lower boss 43 arranged on the lower side of the fixing seat 41. The upper boss 42 is connected with the upper cover 22, while the lower boss 43 is connected with the lower cover 32. The second step groove 421 is arranged on the top of the upper boss 42.
Specifically, the middle cavity 422 is arranged inside the upper boss 42 and runs through the intermediate 4 along the axial direction. A sliding guide groove 121 is arranged along the axial direction on the outer contour surface of the side wing 12 for the firing pin 1. A sliding guide rail 4221 is arranged along the axial direction in the middle cavity 422 to fit with the sliding guide groove 121. This configuration prevents the firing pin 1 from rotating during movement within the middle cavity 422 and increases the minimum distance that an arc could directly pass along the side of the firing pin 1.
In the embodiments of the present disclosure, a sliding seal groove 111 is arranged along the circumferential direction on the outer contour surface of the sliding cylinder 11 for the firing pin 1, and a sliding seal ring 112 is arranged in the sliding seal groove 111. This configuration ensures improved sealing performance of the firing pin 1 during movement in the middle cavity 422, preventing the arc from spilling over and causing safety hazards.
As shown in FIGS. 3, 4 and 9, in the embodiments of the present disclosure, the lower boss 43 is inserted into the inner cavity 321. A fool-proofing concave section 432 is arranged on the outer side of the lower boss 43, and a fool-proofing convex section 3213 is arranged in the inner cavity 321. The fool-proofing concave section 432 adaptively fits with the fool-proofing convex section 3213 to prevent the lower boss 43 from rotating after connection with the lower cover 32. This ensures that the firing pin 1 can reliably cut off the conducting bar 5 and continues its downwards movement towards the inner cavity 321 after cutting off the conducting bar 5. After the lower cover 32 and the lower boss 43 rotate relative to each other, the position of the protruding post 323 changes, which may be unfavorable for the conducting bar 5 to be bent into the avoidance slot 3231, potentially obstructing or causing friction against the continued downward movement of the firing pin 1.
In the embodiments of the present disclosure, a positioning groove 433 is arranged at the bottom end of the lower boss 43 to clamp the top of the dividing wall 322, further preventing relative rotation between the lower cover 32 and the lower boss 43.
In the embodiments of the present disclosure, two arc-crossing walls 434 are symmetrically arranged inside the lower boss 43. When the firing pin 1 cuts off the conducting bar 5, the arc-crossing walls 434 and the impact wall 131 of the firing pin 1 are in clearance fit, creating a narrow space between the firing pin 1 and the arc-crossing wall 434, which serves to weaken the arc after cutting off the conducting bar 5.
To further enhance the aforementioned effect of weakening the arc, as shown in FIG. 10, in one embodiment of the present disclosure, a cavity 435 is formed between each arc-crossing wall 434 and the inner wall of the lower boss 43. One or more cavities 435 can be arranged. A plurality of cavities 435 are arranged at intervals and are not connected to each other. In one embodiment, an energy-absorbing medium including but not limited to steel wool, may be provided in each cavity 435. In another embodiment, the energy-absorbing medium may also not be arranged inside cavity 435.
Moreover, one or more notches 4341 are arranged on the arc-crossing wall 434. The number of notches 4341 can also correspond to the number of cavities 435. In other words, each cavity 435 corresponds to at least one notch 4341. Alternatively, the number of notches 4341 may not correspond to the number of cavities 435; that is, notches 435 are arranged on one part of the cavities 435, while the other part of cavities 435 remain without notches 435.
Further, the notches 4341 connects the cavity 435 with the central space of the lower boss 43. The notches 4341 may have a regular shape, such as strip, or an irregular shape, for example, wider at the top and narrower at the bottom. The height of the notches 4341 is less than that of the arc-crossing wall 434. In other words, the notches 4341 extends downward from the top of the arc-crossing wall 434 to the position above the bottom of the arc-crossing wall 434, rather than extending to the bottom of the arc-crossing wall 434. Additionally, the notches 4341 can be arranged along the axial direction, that is, the longitudinal notches 4341 are parallel to the axis of the lower boss 43 or make a certain angle with the axis of the lower boss 43.
When the firing pin 1 cuts through the conducting bar 5 in use, a narrow space is formed between the firing pin 1 and the arc-crossing wall 434. The notches 4341 passing through the arc-crossing wall 434, the cavities 435 and the energy-absorbing medium, absorb the arc and guide the direction of the arc, preventing the high-temperature arc from damaging the firing pin 1.
In the embodiments of the present disclosure, the fixing seat 41 is provided with a concave contact surface 411 for the fitting of the lower cover 32 on one side facing the lower boss 43. The depth of the concave contact surface 411 is not greater than the thickness of the upper edge of the lower cover 32. Preferably, the depth of the concave contact surface 411 is equal to the thickness of the upper edge of the lower cover 32. This arrangement both enhances the connection sealing performance between the lower cover 32 and the fixing seat 41, and further prevents the relative rotation between the lower cover 32 and the lower boss 43.
As shown in FIG. 3 and FIG. 4, in the embodiments of the present disclosure, the upper structural component 2, the lower structural component 3 and the intermediate 4 are connected using connecting screws 6. Specifically, threaded holes 211 are provided on the lower edge of the upper housing 21, the fixing seat 41, the upper edge of the lower cover 32 and the upper edge of the lower housing 31. The connecting screws 6 pass sequentially through the threaded holes 211 on the upper housing 21, the fixing seat 41, the lower cover 32 and the lower housing 31 to connect the upper housing 21, the fixing seat 41, the lower cover 32 and the lower housing 31 into a whole.
It should be understood that various forms of processes described above may be reordered, or have steps added or removed. For example, the steps described in the present disclosure may be executed in parallel, sequentially, or in different orders, as long as the desired results of the technical proposals disclosed herein can be achieved. No limitation is imposed herein in this regard.
Furthermore, the terms "first" and "second" are used solely for descriptive purposes and are not should not be interpreted as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features described as "first" or "second" may explicitly or implicitly include at least one such feature. Directional terms such as "first direction" and "second direction" refer to certain linear directions unless otherwise specifically defined. In the description of the present disclosure, the term "a plurality of" means two or more unless otherwise explicitly and specifically defined.
The foregoing descriptions are merely embodiments of the present disclosure, and do not limit its protection scope. Any person skilled in the art may readily conceive of variations or substitutions within the technical scope disclosed in the present disclosure, which shall all fall within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope defined by the claims.

Claims

A firing pin, comprising a sliding cylinder (11) whose axial direction is aligned with the overall sliding direction of the firing pin (1), side wings (12) and an impact part (13) connected to one end of the sliding cylinder (11), wherein the impact part (13) comprises at least two impact walls (131), the ends of the two impact walls (131) in the same direction are connected through the side wings (12), the side wings (12) are connected to the sliding cylinder (11), and the outer contour surface of the side wings (12) is located on the extended surface of the outer contour surface of the sliding cylinder (11).
The firing pin according to claim 1, wherein the two sides of the side wing (12) protrude from the impact walls (131).
The firing pin according to claim 1, wherein the impact walls (131) are connected and combined with the side wings (12) to form an impact arc striking structure, which comprises an impact end (132), and an impact step groove (133) is inwardly arranged at the impact end (132).
The firing pin according to claim 1, wherein first filling grooves (1311) are arranged on both the inner and outer surfaces of the impact wall (131).
The firing pin according to claim 1, wherein a sliding seal groove (111) is arranged along the circumferential direction on the outer contour surface of the sliding cylinder (11), and a sliding seal ring (112) is arranged in the sliding seal groove (111).
The firing pin according to claim 1, wherein a sliding guide groove (121) is arranged along the axial direction on the outer contour surface of the side wing (12).
The firing pin according to claim 1, wherein the firing pin (1) is made of high-strength plastic, and an arc-resistant layer is arranged on the surface of the firing pin (1).
An instantaneous circuit breaker, comprising the firing pin (1) in any of claims 1-7, an upper structural component (2), a lower structural component (3), an intermediate (4) and a conducting bar (5); wherein the intermediate (4) is arranged between the upper structural component (2) and the lower structural component (3); a middle cavity (422) for accommodating the impact pin (1) is arranged inwardly along the axial direction on one side that the intermediate (4) is connected with the upper structural component (2); the conducting bar (5) and the intermediate (4) are integrally injection-molded; the conducting bar (5) passes through the middle cavity (422); the firing pin (1) is driven to move from top to bottom in the middle cavity (422) to impact and cut off the conducting bar (5).
The instantaneous circuit breaker according to claim 8, wherein the upper structural component (2) comprises an upper housing (21), an upper cover (22) and an igniter (23); the igniter (23) is injection-molded onto the top of the upper cover (22) and drives the firing pin (1) to move from top to bottom in the middle cavity (422) upon ignition;
wherein the upper structural component (2) further comprises a shading coil (24); a short-circuit slot (221) for installing the shading coil (24) is arranged on the top of the upper cover (22); a lead of the igniter (23) is led out from the short-circuit slot (221); the instantaneous circuit breaker includes a package state and a usage state, and the lead of the igniter (23) is connected to the shading coil (24) in the package state;

the conducting bar (5) is provided with a breaking groove (52) for the firing pin (1) to cut off the conducting bar (5), and a bending groove (53) is also arranged on the inner side of the breaking groove (52) for bending downward after cut-off.
The instantaneous circuit breaker according to claim 9, wherein a first step groove (222) is arranged at one end of the upper cover (22) for connection with the intermediate (4), and a second step groove (421) is arranged on the top of the intermediate (4); when the upper cover (22) and the intermediate (4) are installed, the first step groove (222) is adaptively connected with the second step groove (421); an upper seal ring (223) is arranged between the first step groove (222) and the second step groove (421); the upper housing (21) is arranged on the outer side of the upper cover (22) and the intermediate (4) and covers the joint between the upper cover (22) and the intermediate (4).
The instantaneous circuit breaker according to claim 10, wherein a fool-proofing groove (2221) is arranged on the first step groove (222), and a fool-proofing protrusion (4211) is arranged on the second step groove (421); the fool-proofing protrusion (4211) is clamped in the fool-proofing groove (2221) when the first step groove (222) is adaptively connected with the fool-proofing groove (2221).
The instantaneous circuit breaker according to claim 10, wherein the lower structural component (3) comprises a lower housing (31) and a lower cover (32); an inner cavity (321) is arranged in the lower cover (32); a dividing wall (322) is arranged inside the inner cavity (321) and divides the inner cavity (321) into two arc cavities (3211); a protruding post (323) is arranged on the dividing wall (322) for supporting the conducting bar (5); a post gap (324) is reserved between the two ends of the protruding post (323) and the inner cavity (321) for avoiding the side wings (12);
wherein the firing pin (1) moves from a first position to a second position while moving from top to bottom in the middle cavity (422) and impacting and cutting off the conducting bar (5); when the firing pin (1) is at the first position, the firing pin (1) is located on the upper side of the conducting bar (5); when the firing pin (1) is at the second position, the conducting bar (5) is cut off, and the impact end (132) of the firing pin (1) is located in the inner cavity (321), and the side wing (12) is located in the post gap (324);

wherein a positioning column (325) is arranged on the protruding post (323), and a positioning hole (51) is provided on the conducting bar (5); the positioning column (325) is inserted into the positioning hole (51) after the intermediate and the lower structural component (3) are installed;

wherein avoidance slots (3231) are arranged on both sides of the top of the protruding post (323) for avoiding part of the conducting bar (5) that bends downward after cut-off; second filling grooves (3232) are arranged on two sides of the protruding post (323);

wherein a third step groove (3212) is arranged in the lower cover (32) along the circumferential direction on the upper edge of the inner cavity (321); a fourth step groove (431) is arranged at one end of the immediate (4) for connection with the lower cover (32); the third step groove (3212) is adaptively connected to the fourth step groove (431); a lower seal ring (326) is arranged between the third step groove (3212) and the fourth step groove (431); the lower housing (31) covers the outside of the lower cover (32);

wherein the intermediate (4) comprises a fixing seat (41), an upper boss (42) arranged on the upper side of the fixing seat (41), and a lower boss (43) arranged on the lower side of the fixing seat (41); the upper boss (42) is connected with the upper cover (22), and the lower boss (43) is connected with the lower cover (32); the second step groove (421) is arranged on the top of the upper boss (42); the middle cavity (422) is arranged inside the upper boss (42) and runs through the intermediate (4); a sliding guide rail (4221) is arranged along the axial direction in the middle cavity (422) to fit with the sliding guide groove (121) of the firing pin (1).
The instantaneous circuit breaker according to claim 12, wherein the lower boss (43) is inserted into the inner cavity (321); a fool-proofing concave section (432) is arranged on the outer side of the lower boss (43), and a fool-proofing convex section (3213) is arranged in the inner cavity (321); the fool-proofing concave section (432) adaptively fits with the fool-proofing convex section (3213);
wherein a positioning groove (433) is arranged at the bottom end of the lower boss (43) to clamp the top of the dividing wall (322);

wherein two arc-crossing walls (434) are symmetrically arranged inside the lower boss (43); when the firing pin (1) cuts off the conducting bar (5), the arc-crossing walls (434) and the impact wall (131) of the firing pin (1) are in clearance fit;

wherein a cavity (435) is formed between the arc-crossing wall (434) and the inner wall of the lower boss (43), and one or more notches (4341) are arranged on the arc-crossing wall (434).
The instantaneous circuit breaker according to claim 13, wherein the fixing seat (41) is provided with a concave contact surface (411) for the fitting of the lower cover (32) on one side facing the lower boss (43), and the depth of the concave contact surface (411) is not greater than the thickness of the upper edge of the lower cover (32).
The instantaneous circuit breaker according to claim 14, comprising connecting screws (6); threaded holes (211) are provided on the lower edge of the upper housing (21), the fixing seat (41), the upper edge of the lower cover (32) and the upper edge of the lower housing (31); the connecting screws (6) sequentially pass through the threaded holes (211) on the upper housing (21), the fixing seat (41), the lower cover (32) and the lower housing (31) to connect the upper housing (21), the fixing seat (41), the lower cover (32) and the lower housing (31) into a whole.