EP4679475A1

EP4679475A1 - Striker and instantaneous breaker

Info

Publication number: EP4679475A1
Application number: EP24766243.0A
Authority: EP
Inventors: Chao DAI
Original assignee: Hangzhou Superfuse Technology Co ltd
Current assignee: Hangzhou Superfuse Technology Co ltd
Priority date: 2023-03-06
Filing date: 2024-02-04
Publication date: 2026-01-14
Also published as: CN116259500A; WO2024183521A1

Abstract

The present disclosure provides a firing pin and an instantaneous circuit breaker. The firing pin comprises a sliding cylinder whose axial direction aligns with the overall sliding direction of the firing pin, an impact part connected to one end of the sliding cylinder and side wings arranged on both sides of the impact part. The side wings are connected to the sliding cylinder, and the outer contour surface of the side wings is positioned on the extended surface of the outer contour surface of the sliding cylinder. The instantaneous circuit breaker comprises an upper cover, a lower cover, a conducting bar, an igniter and the firing pin. A middle cavity for accommodating the firing pin is arranged in the upper cover, the conducting bar is arranged between the upper cover and the lower cover, and the igniter is embedded and injection-molded on the top of the upper cover.

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 the circuit. Their primary operating principle is to detect faults in the main circuit and then ignite the igniter, generating high-pressure gas to push the firing pin to cut off the conducting bar and protect the main circuit.
In existing instantaneous circuit breakers, how to improve the movement stability of the firing pin and the accuracy in which it cuts off the fixed position of the conducting bar is an urgent technical problem that needs 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, aiming at addressing at least some of the technical problems present in the prior art.
To achieve the above-mentioned purpose, a 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; an impact part connected to one end of the sliding cylinder; and side wings arranged on both sides of the impact part. The side wings are connected to the sliding cylinder, with the outer contour surface of the side wings positioned on the extension surface of the outer contour surface of the sliding cylinder.
In one embodiment, an impact surface and a diagonal plane are arranged at the end of the impact part far from the sliding cylinder, and the impact surface is coplanar with the end face of the side wings.
A second aspect of the present disclosure provides an instantaneous circuit breaker, comprising an upper cover, a lower cover, a conducting bar, an igniter and the firing pin in the first aspect of the present disclosure. A middle cavity for accommodating the firing pin is arranged in the upper cover. The conducting bar is arranged between the upper cover and the lower cover. The igniter is embedded and injection-molded at the top of the upper cover and pushes the firing pin to move from top to bottom in the middle cavity to impact and cut off the conducting bar upon ignition.
In one embodiment, the conducting bar comprises a terminal, a bending part and a breaking part, a weak part is arranged on the breaking part, a breaking groove for allowing the impact surface to cut off the conducting bar is arranged at one end of the weak part, and a bending groove is arranged at the other end thereof to facilitate the downward bending of the entire weak part after cutting off.
In one embodiment, avoidance grooves for avoiding the side wings are arranged on both sides of the weak part.
In one embodiment, a mounting groove for limiting the bending part is arranged on the side of the upper cover and is adapted to the bending part.
In one embodiment, the generating surface of the igniter is exposed at the inner top of the upper cover. An ignition groove designed to avoid the igniter is arranged at the end of the sliding cylinder far from the impact part and comprises a transition conical surface and an ignition plane. As the firing pin moves downward in the middle cavity from a first position to a second position to impact and cut off the conducting bar, the ignition plane contacts the generating plane of the igniter when the firing pin is positioned at the first position, while an impact gap is maintained between the impact part and the conducting bar.
In one embodiment, mounting locating slots for positioning the breaking part are arranged at the bottom of the upper cover and the top of the lower cover, a sealing groove is arranged along the circumferential direction at the bottom of the upper cover, and a seal ring is arranged in the sealing groove.
In one embodiment, a positioning boss is arranged on the inner side of the sealing groove, and a positioning groove adapted to the positioning boss is arranged on the lower cover.
In one embodiment, an arc extinguishing cavity is arranged inside the lower cover and is used to extinguish and cut off the arc generated by the conducting bar, the upper cover, the conducting bar and the lower cover are connected through fastening screws, and an inner boss for connection with the fastening screws is arranged inside the lower cover and divides the arc extinguishing cavity into a plurality of corner cavities.
In one embodiment, an energy-absorbing medium is arranged at the bottom of the arc extinguishing cavity.
In one embodiment, the arc extinguishing cavity is I-shaped, and energy-absorbing media are arranged in four I-shaped corners of the arc extinguishing cavity.
In the firing pin and the instantaneous circuit breaker of the present disclosure, the firing pin is designed with side wings. In the first aspect, the guide surface length of the firing pin is increased, enhancing its movement stability before cutting off the conducting bar. This ensures that the firing pin does not shift or rotate during movement, thereby allowing it to align accurately with the weak breaking point of the conducting bar to cut off the conducting bar and make the cutting process easier. In the second aspect, the side wings of the firing pin engage with the avoidance grooves on the conducting bar to restrict the radial displacement or rotation of the side wings during the movement of the firing pin, thereby enhancing the stability of the process of the firing pin in cutting off the conducting bar. In the third aspect, the arc generated when the firing pin cuts off the conducting bar moves along the impact surface of the firing pin to the end face of the side wing, then along the outer contour surface of the side wing to the outer guide surface. This extends the arc path, improves arc striking, and enhances the subsequent arc extinguishing effect.
It should be noted that the content described in this section is not intended to identify the key or essential features of the embodiments of the present disclosure, nor to limit its scope. Other features of the present disclosure will become apparent from the following specification.

Brief Description of the Drawings

By referring to the drawings and reading the following detailed description, the above and other objectives, features, and advantages of the exemplary embodiments of the present disclosure will become readily comprehensible. In the drawings, some embodiments of the present disclosure are illustrated by way of example rather than limitation, wherein:
In the drawings, identical or corresponding reference signs denote identical or corresponding parts.

FIG. 1 is a schematic diagram for the structural disassembly of an instantaneous circuit breaker in one embodiment of the present disclosure.
FIG. 2 is a section view of an instantaneous circuit breaker in one embodiment of the present disclosure.
FIG. 3 is a structure diagram of an upper cover in one embodiment of the present disclosure.
FIG. 4 is a structure diagram of an upper cover from another perspective in one embodiment of the present disclosure.
FIG. 5 is a structure diagram of a lower cover in one embodiment of the present disclosure.
FIG. 6 is a structure diagram of a firing pin in one embodiment of the present disclosure.
FIG. 7 is a structure diagram of a firing pin from another perspective in one embodiment of the present disclosure.
FIG. 8 is a structure diagram of a conducting bar in one embodiment of the present disclosure.
FIG. 9 is a structure diagram of a lower cover from another perspective in one embodiment of the present disclosure.
FIG. 10 is a structure diagram of an arc extinguishing cavity with an energy-absorbing medium in one embodiment of the present disclosure.

The above-mentioned drawings include the following reference signs:
1. Upper cover; 11. Middle cavity; 12. Structural reinforcing slot wall; 13. Structural reinforcing boss; 131. Countersunk screw hole; 14. Mounting groove; 15. Sealing groove; 16. Seal ring; 17. Positioning boss; 2. Lower cover; 21. Arc extinguishing cavity; 211. Corner cavity; 212. Energy-absorbing medium; 22. Inner boss; 23. Positioning groove; 24. Countersunk groove; 25. Reinforcing rib; 3. Conducting bar; 31. Terminal; 311. Wiring hole; 32. Bending part; 33. Breaking part; 331. Weak part; 332. Breaking groove; 333. Bending groove; 334. Avoidance groove; 4. Firing pin; 41. Sliding cylinder; 411. Ignition groove; 4111. Transition conical surface; 4112. Ignition plane; 412. Guide surface; 413. Limit surface; 414. Transition rounded corner; 42. Impact part; 421. Impact surface; 422. Diagonal plane; 43. Side wing; 5. Igniter; 6. Fastening screw; 7. Fastening nut; 8. Signal trigger; 81. Shading coil; 82. Shading coil mounting groove; 9. Mounting locating slot.

Detailed Description of the Invention

To make the objectives, features and advantages of the present disclosure more apparent and understandable, 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. Any other embodiments derived by those skilled in the art based on these embodiments, without creative efforts shall fall within the protection scope of the present disclosure.
As shown in FIG. 1 to FIG. 4, the present disclosure provides a firing pin and an instantaneous circuit breaker. The instantaneous circuit breaker comprises an upper cover 1, a lower cover 2, a conducting bar 3, the firing pin 4 and an igniter 5. The upper cover 1 and the lower cover 2 are made of high-strength and high-temperature-resistant plastic materials. A middle cavity 11 for accommodating the firing pin 4 is arranged in the upper cover 1, while the conducting bar 3 is arranged between the upper cover 1 and the lower cover 2. The igniter 5 is embedded and injection-molded at the top of the upper cover 1 and pushes the firing pin 4 to move from top to bottom in the middle cavity 11 to impact and cut off the conducting bar 3 upon ignition .
As shown in FIG. 1, FIG. 2 and FIG. 5, in the embodiments of the present disclosure, an arc extinguishing cavity 21 is arranged inside the lower cover 2 and is used to extinguish and cut off the arc generated by the conducting bar 3, the upper cover 1, the conducting bar 3 and the lower cover 2 are connected through fastening screws 6, an inner boss 22 for connection with the fastening screws 6 is arranged inside the lower cover 2 and divides the arc extinguishing cavity 21 into a plurality of corner cavities 211, and metal flocs for arc striking and extinguishing are filled in the corner cavities 211 to enhance the arc extinguishing capacity of the arc extinguishing cavity 21.
To further enhance the arc extinguishing capability of the arc extinguishing cavity 21, as shown in FIG. 10, in the embodiments of the present disclosure, an energy-absorbing medium 212 can also be arranged at the bottom of the arc extinguishing cavity 21. The energy-absorbing medium 212 includes but is not limited to steel wire mesh or metal flocs.
The bottom of the arc extinguishing cavity 21 refers to either the bottom surface of the arc extinguishing cavity 21, or the lower end of the arc extinguishing cavity 21 close to the bottom surface.
In another embodiment of the present disclosure, the arc extinguishing cavity 21 is I-shaped, d energy-absorbing media 212 are arranged in four I-shaped corners of the arc extinguishing cavity 21. The energy-absorbing medium 212 is provided as a single part or component. In this case, the energy-absorbing medium 212 consists of four energy-absorbing components, which are respectively arranged at the four corners of the arc extinguishing cavity 21.
In addition to the above two arrangements, the energy-absorbing medium 212 can also be arranged at other suitable positions. The present disclosure is not limited in this regard, and users may position the energy-absorbing medium 212 at any other functional locations within the arc extinguishing cavity 21 that effectively achieves the arc extinguishing function.
As shown in FIG. 1 to FIG. 3, in the embodiments of the present disclosure, a signal trigger 8 is arranged on the top on the outer side of the upper cover 1 and is signal-connected to the igniter 5, a shading coil mounting groove 82 is arranged on the signal trigger 8, and a shading coil 81 is installed inside the shading coil mounting groove 82. When the instantaneous circuit breaker is not in use, the shading coil 81 is short-circuited to a lead of the signal trigger 8 to prevent explosion during transportation, thereby enhancing the safety during storage and transportation.
In the embodiments of the present disclosure, the top of the upper cover 1 extends upward from the bottom to form a structural reinforcing slot wall 12, which is connected to the outer wall of the signal trigger 8 through a structural reinforcing boss 13. A countersunk screw hole 131 is arranged on the reinforcing boss 13 for the fastening screw 6 to pass through, and a fastening nut 7 for fitting with the thread of the fastening screw 6 is embedded in the inner boss 22 and is coaxial with the countersunk screw hole 131. The fastening nut 7 engages with the fastening screw 6 to fix the upper cover 1, the conducting bar 3 and the lower cover 2.
As shown in FIG. 6 and FIG. 7, in the embodiments of the present disclosure, the firing pin 4 is made of high-strength plastic materials and can be plated with an arc-resistant coating on the surface. The firing pin 4 comprises a sliding cylinder 41, an impact part 42 and side wings 43, wherein the axial direction of the sliding cylinder 41 aligns with the overall sliding direction of the firing pin 4. The impact part 42 is connected to one end of the sliding cylinder 41, while the side wings 43 are respectively arranged on both sides of the impact part 42 and are connected to the sliding cylinder 41. The generating plane of the igniter 5 is exposed from the inner top of the upper cover 1, an ignition groove 411 for avoiding the igniter 5 is arranged at the end of the sliding cylinder 41 far from the impact part 42 and comprises a transition conical surface 4111 and an ignition plane 4112. The firing pin 4 moves from the first position to the second position during the process of moving from top to bottom in the middle cavity 11 to impact and cut off the conducting bar 3. The ignition plane 4112 is in contact with the generating plane of the igniter 5 when the firing pin 4 is positioned at the first position, allowing the gap between the firing pin 4 and the igniter 5 to be compressed. When exploding, the igniter 5 generates greater thrust on the firing pin 4, making it easier to cut off the conducting bar 3. Additionally, the impact gap between the firing pin 4 and the conducting bar 3 can be increased to prevent the conducting bar 3 from melting the firing pin 4 under high current conditions. When the firing pin 4 is located in the second position, the conducting bar 3 has already been cut off.
In the embodiments of the present disclosure, an impact surface 421 and a diagonal plane 422 are arranged at the end of the impact part 42 far from the sliding cylinder 41. The impact surface 421 is a narrow strip-shaped surface that serves as the main part that generates large pressure to break the conducting bar 3 upon impact and is coplanar with the end face of the side wings 43, helping to form a narrow gap between the firing pin 4 and the lower cover 2 when the firing pin 4 is located at the second position, thereby enhancing the arc extinguishing effect.
As shown in FIG. 2, FIG. 6 and FIG. 8, in the embodiments of the present disclosure, the conducting bar 3 is a red copper part with a relatively low resistance and is electroplated with a coating that provides good conductivity and corrosion resistance on the surface. The conducting bar 3 comprises a terminal 31, a bending part 32 and a breaking part 33. A wiring hole 311 is provided on the terminal 31 and is exposed after installation, aiding in heat dissipation when the product is powered on. A weak part 331 is arranged on the breaking part 33, with a breaking groove 332 to allow the impact surface 421 to cut off the conducting bar 3 is arranged at one end of the weak part 331. A bending groove 333 is arranged at the other end thereof to facilitate the downward bending of the entire weak part 331 after cutting off. During the breaking process of the conducting bar 3, the diagonal plane 422 of the impact part 42 abuts against the weak part 331, causing the entire weak part 331 to bend downward along the bending groove 333.
In the embodiments of the present disclosure, the outer contour surface of the sliding cylinder 41 is the guide surface 412 for the firing pin 4 to move from the first position to the second position. The guide surface 412 engages with the inner surface of the middle cavity 11 to prevent the firing pin 4 from shifting or rotating during movement, thereby ensuring that the impact surface 421 aligns accurately with the breaking groove 332 to cut off the conducting bar 3. The outer contour surface of the side wings 43 is positioned on the extension surface of the outer contour surface of the sliding cylinder 41. On one hand, the increased length of the guide surface 412 enhances the stability of the firing pin 4 throughout its movement. On the other hand, the shortest path that enables the arc to travel needs to pass through the outer contour surface of the sliding cylinder 41 along the outer contour surface of the side wings 43, thereby lengthening the arc.
In the embodiments of the present disclosure, avoidance grooves 334 are arranged on both sides of the weak part 331. When the firing pin 4 cuts off the conducting bar 3, the avoidance grooves 334 avoid the side wings 43, and restricts the radial displacement or rotation of the side wings 43 of the firing pin 4 during the movement of the firing pin 4, thereby enhancing the stability of the cutting process.
As shown in FIG. 3, FIG. 4, FIG. 6 and FIG. 8, in the embodiments of the present disclosure, a mounting groove 14 for limiting the bending part 32 is arranged on the side of the upper cover 1 and is adapted to the bending part 32. When the conducting bar 3 is installed, the bending part 32 is closely attached to the side wall of the mounting groove 14, thereby limiting the relative displacement between the conducting bar 3 and the upper cover 1. This ensures that there is no relative displacement between the breaking groove 332 and the impact surface 421 during the process of the firing pin 4 cutting off the conducting bar 3, and improving the accuracy of the action of cutting off the conducting bar 3.
As shown in FIG. 6, in the embodiments of the present disclosure, a limit surface 413 is also arranged on the side where the sliding cylinder 41 is connected to the impact part 42 to prevent the firing pin 4 from moving further downward after breaking the conducting bar 3. A transition rounded corner is formed between the impact part 42 and the limit surface 413 to reduce stress concentration.
As shown in FIG. 4 and FIG. 5, in the embodiments of the present disclosure, mounting locating slots 9 are arranged at the bottom of the upper cover 1 and the top of the lower cover 2 to accommodate the breaking part 33. When the conducting bar 3 is installed, the breaking part 33 is clamped in the mounting locating slot 9, thereby restricting the displacement of the conducting bar 3. A square-shaped sealing groove 15 is arranged along the circumferential direction at the bottom of the upper cover 1, and a seal ring 16 is arranged in the sealing groove 15 to prevent dangerous gases from being ejected from the product mounting clearance during the breaking process. A positioning boss 17 is arranged on the inner side of the sealing groove 15, and a positioning groove 23 adapted to the positioning boss 17 is arranged on the lower cover 2. The positioning boss 17 corresponds to the positioning groove 23, serving both physical positioning and sealing functions.
As shown in FIG. 9, in the embodiments of the present disclosure, a plurality of countersunk grooves 24 are provided at the bottom of the lower cover 2, and reinforcing ribs 25 are formed between the countersunk grooves 24, thereby enhancing the structural strength of the bottom of the lower cover 2.
It should be understood that various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present disclosure may be executed in parallel, sequentially, or in a different order, provided that the desired outcome 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 for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly specifying the quantity of the referenced technical features. Accordingly, features labeled 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 specific linear orientations unless otherwise explicitly 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 the protection scope of the present disclosure is not limited thereto. 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 in the claims.

Claims

A firing pin, comprising a sliding cylinder (41) whose axial direction aligns with the overall sliding direction of the firing pin (4), an impact part (42) connected to one end of the sliding cylinder (41) and side wings (43) arranged on both sides of the impact part (42). The side wings (43) are connected to the sliding cylinder (41), and the outer contour surface of the side wings (43) is positioned on the extension surface of the outer contour surface of the sliding cylinder (41).
The firing pin according to claim 1, wherein an impact surface (421) and a diagonal plane (422) are arranged at the end of the impact part (42) far from the sliding cylinder (41), and the impact surface (421) is coplanar with the end face of the side wings (43).
An instantaneous circuit breaker, comprising an upper cover (1), a lower cover (2), a conducting bar (3), an igniter (5) and the firing pin (4) in any of claims 1-2, and a middle cavity (11) for accommodating the firing pin (4) is arranged in the upper cover (1). The conducting bar (3) is arranged between the upper cover (1) and the lower cover (2), and the igniter (5) is embedded and injection-molded on the top of the upper cover (1) and can push the firing pin (4) to move from top to bottom in the middle cavity (11), thereby impacting and cutting off the conducting bar (3) upon ignition.
The instantaneous circuit breaker according to claim 3, wherein the conducting bar (3) comprises a terminal (31), a bending part (32) and a breaking part (33), a weak part (331) is arranged on the breaking part (33), a breaking groove (332) for allowing the impact surface (421) to cut off the conducting bar (3) is arranged at one end of the weak part (331), and a bending groove (333) is arranged at the other end thereof to facilitate the downward bending of the entire weak part (331) after cutting off.
The instantaneous circuit breaker according to claim 4, wherein avoidance grooves (334) for avoiding the side wings (43) are arranged on both sides of the weak part (331).
The instantaneous circuit breaker according to claim 4, wherein a mounting groove (14) for limiting the bending part (32) is arranged on the side of the upper cover (1) and is adapted to the bending part (32).
The instantaneous circuit breaker according to claim 5, wherein the generating plane of the igniter (5) is exposed from the inner top of the upper cover (1), an ignition groove (411) for avoiding the igniter (5) is arranged at the end of the sliding cylinder (41) far from the impact part (42) and comprises a transition conical surface (4111) and an ignition plane (4112), the firing pin (4) moves from the first position to the second position during the process of moving from top to bottom in the middle cavity (11) to impact and cut off the conducting bar (3), the ignition plane (4112) contacts the generating plane of the igniter (5) when the firing pin (4) is positioned at the first position, and an impact gap exists between the impact part (42) and the conducting bar (3).
The instantaneous circuit breaker according to claim 3, wherein mounting locating slots (9) for placing the breaking part (33) are arranged at the bottom of the upper cover (1) and the top of the lower cover (2), a sealing groove (15) is arranged along the circumferential direction at the bottom of the upper cover (1), and a seal ring (16) is arranged in the sealing groove (15).
The instantaneous circuit breaker according to claim 8, wherein a positioning boss (17) is arranged on the inner side of the sealing groove (15), and a positioning groove (23) adapted to the positioning boss (17) is arranged on the lower cover (2).
The instantaneous circuit breaker according to claim 3, wherein an arc extinguishing cavity (21) is arranged inside the lower cover (2) and is used to extinguish and cut off the arc generated by the conducting bar (3), the upper cover (1), the conducting bar (3) and the lower cover (2) are connected through fastening screws (6), and an inner boss (22) for connection with the fastening screws (6) is arranged inside the lower cover (2) and divides the arc extinguishing cavity (21) into a plurality of corner cavities (211).
The instantaneous circuit breaker according to claim 10, wherein an energy-absorbing medium (212) is arranged at the bottom of the arc extinguishing cavity (21).
The instantaneous circuit breaker according to claim 10, wherein the arc extinguishing cavity (21) is I-shaped, and energy-absorbing media (212) are arranged at the four I-shaped corners of the arc extinguishing cavity (21).