CN107919249B

CN107919249B - Intelligent fuse

Info

Publication number: CN107919249B
Application number: CN201711372071.4A
Authority: CN
Inventors: 樊华; 王荣辉; 石晓光
Original assignee: Xian Zhongrong Electric Co Ltd
Current assignee: Xian Zhongrong Electric Co Ltd
Priority date: 2017-12-19
Filing date: 2017-12-19
Publication date: 2020-05-26
Anticipated expiration: 2037-12-19
Also published as: CN107919249A

Abstract

An intelligent fuse comprises a shell, and is characterized in that a gas generating device is arranged at the lower end in the shell, and a punch driven by gas released by the gas generating device is arranged above the gas generating device; the punch can move up and down in the shell; a melt is arranged in the shell above the punch, a large groove is formed in the melt, and a small groove is formed in one end in the large groove; the punching knife of the punch is just positioned below the small groove; an arc extinguish chamber with a grid is arranged above the melt and communicated with the outside. The fuse has high response speed, is not only suitable for breaking a circuit under the condition of overload current, but also suitable for breaking the circuit under the impact force of external force, and is more suitable for being used on vehicles which are impacted by external force, such as new energy automobiles and the like.

Description

Intelligent fuse

Technical Field

The invention relates to a fuse, in particular to a fuse structure which can quickly respond and quickly cut off a main circuit in a fusing protection device of the main circuit when a new energy automobile and the like suffer from impact or other accidents.

Background

The fuse is a common electrical component and plays a role in protecting a circuit. When a general fuse circuit is overloaded, the fuse element is heated by overload current to fuse the fuse element quickly, so that the circuit is disconnected to realize circuit protection. With the development and the gradual popularization of new energy automobiles, the new energy automobiles use a large number of battery packs, and a main circuit for providing power for the new energy automobiles is involved. The existing fuse fusing the fuse melt through heating is used in the main circuit of the new energy automobile, and when the new energy automobile is subjected to other sudden accidents such as collision and the like, the common fuse has no time to fuse the disconnection circuit to lose power of the new energy automobile, so that potential safety hazards are caused or accidents are enlarged, and serious consequences are caused.

Disclosure of Invention

The invention aims to solve the technical problem of providing an intelligent fuse which can quickly break a fuse body when suffering from overload or accidents, thereby breaking a main circuit and realizing circuit protection, and has high response rate and good safety performance.

In order to solve the technical problems, the technical scheme provided by the invention is an intelligent fuse which comprises a shell and is characterized in that a gas generating device is arranged at the lower end in the shell, and a punch driven by gas released by the gas generating device is arranged above the gas generating device; the punch can move up and down in the shell; a melt is arranged in the shell above the punch, a large groove is formed in the melt, and a small groove is formed in one end in the large groove; the punching knife of the punch is just positioned below the small groove; an arc extinguish chamber with a grid is arranged above the melt and communicated with the outside.

A fastening piece is fixed on the periphery of the release end of the gas generating device, a circle of convex rib is arranged on the periphery of the lower end of the fastening piece, a groove corresponding to the convex rib is formed in the shell, and the convex rib is positioned in the groove; the punch is sleeved on the fastener, and a sealing ring for sealing a gap between the fastener and the punch is arranged on the outer peripheral surface of the fastener; the periphery of the gas generating device, which is close to the lower end, is provided with a circle of limiting bosses, limiting steps corresponding to the limiting bosses of the gas generating device are arranged in the shell, which is close to the lower end, and the limiting bosses are abutted against the limiting steps to limit the gas generating device.

The periphery of the convex ridge of the fastener and the groove surface of the groove corresponding to the periphery of the convex ridge are both provided with a regular square structure with at least a regular square structure.

The punch is provided with a hollow part, a punching knife is arranged on the punch, and the width of the punching knife is larger than or equal to that of the small groove of the melt.

And corresponding limiting grooves which are vertically opened upwards are formed in the corresponding two sides of the shell corresponding to the two ends of the punching knife, and the two ends of the punching knife are respectively positioned in the limiting grooves.

And a plurality of exhaust grooves are formed in the inner wall of the shell, and openings of the exhaust grooves are communicated with the arc extinguish chamber.

The melt comprises two parallel side walls and a top wall connected with the two side walls, and the large groove is formed in the top wall; a contact knife is bent and extended at the same side end of the two side walls; the contact knife is positioned outside the shell.

The melt accommodating cavity for accommodating the melt is positioned on the upper surface and two sides of the punch accommodating cavity for accommodating the punch; the top wall of the melt is positioned above the punch head accommodating cavity, and two side walls of the melt are respectively positioned at two sides of the punch head accommodating cavity; the punch head accommodating cavity is of a hollow cylindrical structure; a group of limiting grooves with upward vertical openings are oppositely arranged on the inner wall of the hollow cylindrical structure and the containing area which is positioned above the inner wall and used for containing the top wall of the melt; the punch is of a hollow cylindrical structure, and the punching knife is arranged on the punch; the punch is matched with the punch containing cavity, and two ends of the punching knife are respectively arranged in the limiting grooves.

The shell is divided into a left shell and a right shell, the left shell is divided into a lower part and an upper part, and the right shell is divided into a lower part, a middle part and an upper part; the lower part of the left shell and the lower part of the right shell have the same structure, and the left shell and the right shell are respectively provided with a semicircular groove for limiting a convex edge of the fastener and a semicircular limiting step for limiting a limiting boss of the gas generating device; the upper part of the left shell comprises two side walls of the shell, a halved semi-arc punch head accommodating cavity, a half part of melt accommodating cavity and an accommodating cavity for accommodating the arc extinguish chamber; the middle part of the right shell comprises a halved semi-arc-shaped punch head accommodating cavity; the upper part of the right housing is a part of the side wall of the housing covering the space upward from the punch accommodating chamber.

The top of explosion chamber be provided with the exhaust hole of grid space intercommunication.

The intelligent fuse of the invention, the gas generating device is connected with an external sensor, and the fused mass is connected with an external circuit to realize the protection of equipment and instruments using the circuit. The common fuse realizes the circuit breaking only by fusing the fuse through the heating of heavy current overload, but the corresponding speed is slow, and when the fuse receives impact, impact and other external huge destructive force in the twinkling of an eye, the common fuse can not fuse the circuit breaking at the first time. However, the intelligent fuse is respectively connected with an external current sensor and a sensor for sensing external impact force and the like, when the intelligent fuse is impacted by external force, the impact force sensor can send a signal to the gas generating device, so that the gas generating device generates high-pressure gas, and the punch is driven to break the melt to realize circuit disconnection; when the current sensor senses the overload current, the current sensor also sends a signal to the gas generating device, so that high-pressure gas generated by the gas generating device drives the punch to break the melt to realize circuit breaking. The fuse has high response speed, is not only suitable for breaking a circuit under the condition of overload current, but also suitable for breaking the circuit under the impact force of external force, and is more suitable for being used on vehicles which are impacted by external force, such as new energy automobiles and the like.

Drawings

FIG. 1 is a schematic diagram of a fuse according to the present invention.

FIG. 2 is a schematic cross-sectional view of the present invention.

Fig. 3 is a schematic diagram of the explosive structure of the present invention.

Detailed Description

With respect to the above technical solutions, a preferred embodiment will be described in detail with reference to the drawings. Referring to fig. 1 to 3, the fuse of the present invention includes a housing of the fuse, a gas generating device, a punch, a melt, and an arc extinguishing chamber, among others.

The housing 1 includes left and

right housings

2 and 3 and a housing cover (not shown), and is made of a high-strength and high-temperature-resistant plastic material. The housing is injection molded from a high strength, high temperature, insulative, injection molded material. Left shell 2, its front and back lateral wall upper portion width is greater than the fractional part width, and lower part right-hand member face intersects 90 degrees with the lower extreme of upper portion, and lower part right-hand member face is the parallel plane with the upper portion right-hand member face. The lower part of the left shell is sequentially connected from bottom to top and is provided with semicircular arc grooves (21, 22 and 23), the radius of the semicircular arc groove 21 is smaller than that of the semicircular arc groove 22, the radius of the semicircular arc groove 22 is smaller than that of the semicircular arc groove 23, the arc groove face of the semicircular arc groove 23 is divided into three planes, and the angle between every two adjacent planes is 120 degrees. Of course, the arc-shaped groove surface can be equally divided into other planes, such as two planes, four planes and the like, according to the requirement. The connecting surface between the semi-arc groove 21 and the semi-arc groove 22 is a limiting step; the connection surface between the semi-arc groove 23 and the semi-arc groove 22 is a limit step, and the arc edge of the semi-arc groove 23 is provided with a limit arc-shaped convex edge 24.

A semicircular arc groove 25 is separately arranged on the upper part of the left outer shell above the limit arc-shaped convex edge of the left outer shell, and the end surfaces of the two ends of the semicircular arc groove 25 and the right end surface of the lower part of the left outer shell are positioned on the same plane; the radius of the semi-circular groove 25 is larger than that of the semi-circular groove 22. The front and rear side walls of the left shell are respectively and correspondingly provided with a clamping groove 26, and the clamping groove 26 extends into the space between the semi-circular arc-shaped groove 25 and the front and rear side walls. The front and rear side walls above the position-limiting groove 26 are respectively and correspondingly provided with a position-limiting clamping groove 28, and the width between the position-limiting clamping grooves 28 on the front and rear side walls is smaller than the width between the position-limiting clamping grooves 26 on the front and rear side walls. And the upper end surfaces of the front and rear side walls at the two ends of the limiting clamping groove 28 are respectively provided with a limiting clamping groove 29 downwards. The spacing up end of screens recess 26 is located semi-circular arc groove 25 top, is provided with spacing draw-in groove 27 between the spacing upper end of the up end of semi-circular arc groove 25 and spacing draw-in groove 28, and both ends communicate with each other with rather than adjacent screens draw-in groove 26 around spacing draw-in groove 27 respectively. A limiting block 271 is arranged on the limiting clamping groove 27 positioned above the semi-circular-arc-shaped groove 25. In the central part between the semi-circular arc-shaped groove 25 and the limiting block 271 located between the clamping grooves 26, a limiting groove 30 parallel to the axis is formed downwards from the upper end surface, exhaust grooves 31 are respectively formed at two sides of the limiting groove 30 at a certain distance, and the upper end openings of the limiting groove 30 and the exhaust grooves 31 are respectively communicated with the accommodating space formed by the limiting clamping grooves 28 at the front side and the rear side. The length of the vent groove 31 is greater than that of the limiting groove 30.

And the right shell 3 is made of high-strength high-temperature-resistant injection molding materials. The lower part of the structure is the same as the left shell structure and is a corresponding structure matched with each other. The width of the front and rear side walls of the middle portion of the right housing is the same as the width of the front and rear side walls of the lower portion thereof. The distance between the outer side surfaces of the front and rear side walls of the middle part is smaller than the distance between the outer side surfaces of the front and rear side walls of the lower part. A semi-circular arc groove 32 corresponding to the semi-circular arc groove 25 is formed in the middle of the right housing, and after assembly, the end surfaces of the two ends of the semi-circular arc groove 25 correspond to the end surfaces of the two ends of the semi-circular arc groove 32. A limit stop wall 33 extends upward from the right side wall of the lower part and the outer side of the front and rear side walls in the right housing middle part. The upper portion of right shell is the last right side wall 34 with spacing wall 32 thickness the same, and the width of going up right side wall 34 is the same with the width between the lateral surface of the lower part front and back lateral wall of right shell, and after the equipment, the up end of going up right side wall is the flush with the up end of left shell. A stopper 35 corresponding to the stopper 271 is provided in the upper right sidewall 34 at the upper end face of the semicircular arc-shaped groove 32. The semicircular groove 32 and the limiting block 35 connected with the semicircular groove are respectively provided with a limiting groove 36 and an exhaust groove 37 which are respectively corresponding to the limiting groove 30 and the exhaust groove 31 on the semicircular groove 25, and the upper end openings of the limiting groove 36 and the exhaust groove 37 are positioned on the upper end surface of the limiting block 35.

The Micro Gas Generator (MGG)4 is a purchased part, and is divided into three parts, namely an electrode end 41, a pyrotechnic chamber 42 and a gas release end 43, wherein the peripheral wall of the gas release end is provided with a notch 44, and the end face of the gas release end is provided with a gas release port. The fastening piece 5 is fastened on the MGG, the fastening piece 5 is of a hollow structure, the structure of the hollow part is the same as that of the gas release end at the gap, and when the fastening piece is sleeved on the MGG, the gap on the MGG limits the position of the fastening piece 5, so that the fastening piece and the MGG can be prevented from rotating mutually. The clamping convex ribs 51 matched with the semicircular grooves 23 are arranged on the outer peripheral wall of the lower end of the MGG fastener, and six angles, namely 120 degrees between two adjacent surfaces, are arranged on the outer peripheral surface of each clamping convex rib. A ring of stopper groove 52 is provided on the upper end outer peripheral surface of the MGG fastener 5, and a seal ring 53 is provided in the stopper groove 52.

And the punch 6 is made of high-strength high-temperature-resistant injection molding material. The sealing device comprises a hollow cylindrical barrel 61 sleeved on a fastening piece 5, and the cylindrical barrel and the fastening piece are sealed through a sealing ring. A die cutter 52 is provided on the cylindrical barrel. The die cutter 52 is a sheet-like structure. The cylindrical shape matches with the semi-circular arc-shaped groove 25. When the punch is mounted in the fuse housing, the ends of the punch are located in the

retaining recesses

30 and 36, respectively.

The melt 7 is a conductive material, and may be a conductive metal such as aluminum or copper. The device comprises two side walls and a top wall which are arranged at intervals in parallel, wherein the upper ends of the two side walls are connected with the top wall through arc-shaped surfaces. The arc-shaped surface connection can avoid tip arcing when the melt is broken. And limiting grooves 71 are respectively and correspondingly formed at the two ends of the top wall corresponding to the widths and the thicknesses of the limiting blocks 35 and the limiting blocks 271. A recess 72 is formed in the top wall to reduce the thickness of the top wall. A shallow groove 73 with a similar V-shaped structure or U-shaped structure is formed at one end in the groove 72, and a groove 74 with a V-shaped structure is further formed at the other end in the groove 72. The depth of the V-shaped groove 74 is greater than the depth of the shallow groove 73. Compared with the groove structure with other shapes, the stress points of the groove with the V-shaped structure are more concentrated and are easier to break. The V-shaped configuration of the groove 74 is located just above the punch after melt installation. The contact knives 75 are arranged on the same side ends of the two side walls at 90 degrees respectively, and the contact knives 75 are connected with the side walls through arc-shaped surfaces respectively. The contact blade 75 is provided with a connection hole to be connected to an external circuit.

The arc extinguishing chamber 8 is an injection molding part, and is provided with a plurality of grids for arc extinguishing. And the top of the arc extinguish chamber is provided with an exhaust hole 81 communicated with the grid space. The arc chute 8 may be received in the limit slot 28 when assembled.

The fuse cover plate (not shown) is provided with a convex rib corresponding to the limiting clamping groove 29, and when the fuse cover plate is installed, the convex rib is embedded into the limiting clamping groove 29.

When all parts of the fuse are assembled, the position relation of all the parts is as follows: the gas generating device MGG sleeved with the fastening piece is accommodated in the circular accommodating cavities formed by the semicircular arc-shaped grooves (21, 22 and 23) of the left shell and the semicircular arc-shaped grooves of the right shell corresponding to the semicircular arc-shaped grooves, the connecting part of the electrode end of the MGG and the pyrotechnic composition chamber is provided with a step, and the limiting step formed between the semicircular arc-shaped groove 21 and the semicircular arc-shaped groove 22 is just matched with the step at the electrode end of the MGG and the pyrotechnic composition chamber to be pressed, so that the position of the MGG is limited, and the MGG is prevented from falling from the accommodating cavities. The clamping convex rib 51 of the fastener installed on the MGG is just inserted into the circular containing cavity with a regular hexagonal surface formed by the semicircular arc-shaped groove 23 of the left shell and the semicircular arc-shaped groove on the right shell corresponding to the semicircular arc-shaped groove to position the clamping convex rib. Due to the hexagonal shape of the receiving cavity, the fastener is prevented from rotating relative to the housing. The punch is sleeved on the fastener, the cylindrical part of the punch is positioned in a circular accommodating cavity formed by the semi-arc-shaped groove 25 of the left shell and the semi-arc-shaped groove 31 of the right shell corresponding to the semi-arc-shaped groove, two ends of the punch are respectively positioned in the limiting groove 30 and the limiting groove 35, and the punch can move up and down along the two limiting grooves under the action of external force. And the top wall of the melt 7 is accommodated in the limiting clamping groove 27 on the upper end face of the accommodating cavity formed by the semicircular arc groove 25 and the semicircular arc groove 31, and two ends of the top wall of the melt are clamped and positioned in the limiting groove 71 through the limiting block 271 and the limiting block 34 respectively. The two side walls of the melt are respectively positioned in the clamping groove 26 between the accommodating cavity formed by the semi-arc-shaped groove 25 and the semi-arc-shaped groove 31 and the side wall of the shell and are tightly attached to the inner walls of the front side wall and the rear side wall of the shell. The contact knife of the melt extends out of the outer shell. The groove 74 of the V-shaped structure in the melt is located just above the die cutter and at a distance therefrom. In the limiting clamping groove 28 on the melt, the arc extinguishing chamber 8 is accommodated.

The working principle of the invention is as follows: the electrode end of the gas generating device MGG is connected with an external sensor, and the contact knife of the melt is connected with a circuit. When abnormal signals such as impact or heavy current are received, the sensor sends signals to the electrode end to trigger the ignition device to ignite, pyrotechnic materials in the pyrotechnic chamber are made to react to generate a large amount of high-pressure gas and the high-pressure gas is released from the gas release end, the high-pressure gas impacts the punch after passing through the fastener and drives the punch to move upwards, under strong acting force, the punch moves upwards and collides with the groove 74 of the melt in the V-shaped structure to cut off the melt, and after the melt is cut off, a part of the melt is downward dropped under the action of gravity along the shallow groove on the melt. At the moment, gas flows to the arc extinguish chamber along the exhaust groove on the shell and the opening after the fused mass is broken and overflows to the outside of the fuse shell through the arc extinguish chamber; meanwhile, the electric arc generated at the melt is blown into the arc extinguishing chamber under the action of the gas for arc extinguishing.

Compared with the common fuse which is fused only through large current, the fuse has the advantages that: when external force impact or other impact is received, the fuse-element can be quickly reacted to break the melt, so that the circuit is broken, the protection effect is realized, the quick response speed is realized, the circuit is broken in the shortest time, and the equipment connected with the circuit is protected. This is an incomparable advantage over conventional fuses.

Claims

1. An intelligent fuse comprises a shell, and is characterized in that a gas generating device is arranged at the lower end in the shell, and a punch driven by gas released by the gas generating device is arranged above the gas generating device; the punch can move up and down in the shell; a melt is arranged in the shell above the punch, a large groove is formed in the melt, and a small groove is formed in one end in the large groove; the punching knife of the punch is just positioned below the small groove; an arc extinguish chamber with a grid is arranged above the melt and is communicated with the outside;

a fastening piece is fixed on the periphery of the release end of the gas generating device, a circle of clamping convex ribs are arranged on the periphery of the lower end of the fastening piece, grooves corresponding to the clamping convex ribs are formed in the shell, and the clamping convex ribs are located in the grooves; the punch is sleeved on the fastener, and a sealing ring for sealing a gap between the fastener and the punch is arranged on the outer peripheral surface of the fastener; a circle of limiting bosses are arranged on the periphery of the gas generating device close to the lower end, limiting steps corresponding to the limiting bosses of the gas generating device are arranged in the shell close to the lower end, and the limiting bosses abut against the limiting steps to limit the gas generating device;

the melt accommodating cavity for accommodating the melt is positioned on the upper surface and two sides of the punch accommodating cavity for accommodating the punch;

the melt comprises two parallel side walls and a top wall connected with the two side walls, and the large groove is formed in the top wall; a contact knife is bent and extended at the same side end of the two side walls; the contact knife is positioned outside the shell;

the shell is divided into a left shell and a right shell, the left shell is divided into a lower part and an upper part, and the right shell is divided into a lower part, a middle part and an upper part; the lower part of the left shell and the lower part of the right shell have the same structure, and the left shell and the right shell are respectively provided with a semicircular groove for limiting the clamping convex edge of the fastener and a semicircular limiting step for limiting the limiting boss of the gas generating device; the upper part of the left shell comprises two side walls of the shell, a halved semi-arc punch head accommodating cavity, a half part of melt accommodating cavity and an accommodating cavity for accommodating the arc extinguish chamber; the middle part of the right shell comprises a halved semi-arc-shaped punch head accommodating cavity; the upper part of the right housing is a part of the side wall of the housing covering the space upward from the punch accommodating chamber.

2. The intelligent fuse as claimed in claim 1, wherein the periphery of the locking rib of the fastening member and the groove surface of the corresponding groove are arranged in a regular polygonal structure.

3. An intelligent fuse according to claim 1, characterised in that the punch has a hollow, on which a die is mounted, the width of the die being greater than or equal to the width of the small recess of the melt;

corresponding limiting grooves which are vertically opened upwards are formed in the corresponding two sides of the shell corresponding to the two ends of the stamping knife, and the two ends of the stamping knife are respectively positioned in the limiting grooves;

the top wall of the melt is positioned above the punch head accommodating cavity, and two side walls of the melt are respectively positioned at two sides of the punch head accommodating cavity; the punch head accommodating cavity is of a hollow cylindrical structure; the punch is of a hollow cylindrical structure, and the punching knife is arranged on the punch; the punch is matched with the punch containing cavity.

4. An intelligent fuse as recited in claim 1, wherein a plurality of vent slots are formed in an inner wall of said housing, said vent slots having openings in communication with said arc chute.

5. An intelligent fuse according to claim 1, characterised in that the top of the arc extinguishing chamber is provided with an exhaust vent communicating with the grid space.