CN109686628B

CN109686628B - Plastic case circuit breaker

Info

Publication number: CN109686628B
Application number: CN201910055555.9A
Authority: CN
Inventors: 孙龙; 周建勇
Original assignee: Zhejiang Minghui Intelligent Electric Co Ltd
Current assignee: Zhejiang Minghui Intelligent Electric Co Ltd
Priority date: 2019-01-22
Filing date: 2019-01-22
Publication date: 2020-02-07
Anticipated expiration: 2039-01-22
Also published as: CN109686628A

Abstract

The invention discloses a molded case circuit breaker, which belongs to the field of circuit breakers, and adopts the technical scheme that the molded case circuit breaker comprises a shell, a breaking mechanism and a thermomagnetic tripper, wherein the breaking mechanism and the thermomagnetic tripper are arranged in the shell, the breaking mechanism comprises a movable contact structure, a static contact structure and a reset structure, the movable contact structure comprises a rotating shaft shell and a conductive clamping plate fixedly connected to the shell, the rotating shaft shell is rotatably connected to the conductive clamping plate, the conductive clamping plate is hinged with a movable contact, the rotating shaft shell is provided with a repulsion structure for driving the movable contact to rotate and to abut against the rotating shaft shell, the length of the movable contact is larger than the distance between the rotating axis and the static contact structure, the reset structure comprises a guy cable, one end of the guy cable is fixedly connected to the movable contact and far. The invention has the effect of automatically resetting the movable contact.

Description

Plastic case circuit breaker

Technical Field

The invention relates to the technical field of circuit breakers, in particular to a molded case circuit breaker.

Background

The molded case circuit breaker can automatically cut off the current after the current exceeds the trip setting. Plastic housing refers to the use of plastic insulators as the outer housing of the device to isolate the conductors from each other and from the grounded metal parts. Molded case circuit breakers typically contain a thermo-magnetic trip unit, while large molded case circuit breakers are equipped with a solid state trip sensor.

At present, chinese patent application with publication number CN205069552U discloses a contact repellence device of a molded case circuit breaker, which is sequentially provided with a static contact support plate, a connecting plate, a U-shaped plate, a static silver contact, a dynamic contact, a plate hole, a first shaft, a second shaft, a spring, a third shaft, a rotating shaft and an actuator hole, wherein the static contact support plate is connected with the U-shaped plate through the connecting plate, the dynamic silver contact is arranged on the upper side of the static silver contact and fixed on the dynamic contact, the plate hole is arranged on the left side of the dynamic contact, the first shaft is installed on the right side of the dynamic contact, the second shaft is arranged on the lower side of the first shaft and connected with the third shaft through the spring, the rotating shaft is arranged on. The moulded case circuit breaker contact repelling device improves the breaking capacity, but does not increase the parts and the structure of the contact device, and has relatively simple structure and no cost increase.

The above prior art solutions have the following drawbacks: make the elastic force that makes the contact overcome the torsional spring under the effect of electronic repulsion and rotate, make the second shaft contradict in the outside of spring dog-ear after rotating to the spring is applyed and is changed with the epaxial power of second, thereby makes the contact rotate along the direction of electronic repulsion syntropy, thereby has realized the purpose of quick disconnection, but need manual reset after disconnecting, makes the second shaft contradict in the spring dog-ear inboard, thereby leads to moulded case circuit breaker to use inconvenient.

Disclosure of Invention

The invention aims to provide a molded case circuit breaker capable of automatically resetting a movable contact.

In order to achieve the purpose, the invention provides the following technical scheme: a molded case circuit breaker, characterized in that: comprises a shell, a breaking mechanism and a thermomagnetic release, wherein the breaking mechanism and the thermomagnetic release are arranged in the shell, the breaking mechanism comprises a movable contact structure, a static contact structure and a reset structure, the movable contact structure comprises a rotating shaft shell and a conductive clamping plate fixedly connected with the shell, the rotating shaft shell is rotatably connected with the conductive clamping plate, a torsion spring for driving the rotating shaft shell to rotate is arranged between the conductive clamping plate and the rotating shaft shell, the conductive clamping plate is hinged with a moving contact, the rotating shaft shell is provided with a repulsion structure which drives the moving contact to rotate and is abutted against the rotating shaft shell, the repulsion structure drives the moving contact to rotate in a direction opposite to the direction in which the torsion spring drives the rotating shaft shell to rotate, the length of moving contact is greater than the interval between its axis of rotation and the stationary contact structure, reset structure includes that one end fixed connection keeps away from the cable of its pivot axis in the moving contact, the cable is in addition through setting up buffer structure fixed connection in the stationary contact structure.

By adopting the technical scheme, when the current passing through the short-circuit device is overlarge, electric repulsion force can be generated, and under the action of the electric repulsion force, the moving contact can repel the structure and rotate towards the direction far away from the static contact, so that an included angle is formed between the moving contact and the shell of the rotating shaft; the tripping device is triggered by too large current to enable the rotating shaft shell to rotate under the action of the torsion spring, so that the distance between the moving contact and the static contact is further increased, and the moving contact rotates downwards under the pulling force of the inhaul cable to automatically reset.

The invention is further configured to: the moving contact is provided with a threading hole, the stay cable penetrates through the threading hole, and two ends of the stay cable are fixedly connected with the buffer structure respectively.

Through adopting above-mentioned technical scheme, make the connection structure of cable and moving contact simple more reliable.

The invention is further configured to: one end of the moving contact far away from the conductive clamping plate is fixedly connected with a moving contact plate made of metal materials, and the width of the moving contact plate is larger than that of the moving contact.

Through adopting above-mentioned technical scheme, utilize the movable contact plate increase moving contact and decide the area of contact between the contact, reduce the pressure between the two, make the contact damage when avoiding conflicting between the two.

The invention is further configured to: the static contact structure includes the U-shaped plate, the crooked U-shaped groove that forms of U-shaped plate one end, the U-shaped inslot is equipped with the iron core, the iron core is along the both ends fixedly connected with U-shaped magnetic conduction piece of U-shaped plate width, two U-shaped magnetic conduction piece one end difference fixed connection is in the both ends terminal surface of iron core, and its other end is close to each other.

By adopting the technical scheme, when the static contact is contacted with the moving contact, current is generated in the U-shaped plate, a magnetic field is generated in the iron core under the action of the current, the direction of the magnetic induction line is changed under the action of the U-shaped magnetic conduction blocks at the two ends of the iron core, and the magnetic induction line is concentrated between the end surfaces of the two U-shaped magnetic conduction blocks, so that the influence of the magnetic field generated by the two adjacent static contacts is reduced, the magnetic induction line is concentrated, the magnetic field intensity is increased, and further the electric repulsion force is increased.

The invention is further configured to: and a static contact plate made of silver-copper alloy is fixedly connected to the outer wall of the U-shaped groove far away from one end of the U-shaped plate.

By adopting the technical scheme, the static contact plate is made of the silver-copper alloy, so that the rigidity is high, the conductivity is good, the static contact abuts against the static contact plate, the conduction of the static contact and the moving contact is realized, and the U-shaped plate is protected by the static contact plate to avoid the extrusion deformation of the driven contact.

The invention is further configured to: u-shaped plate one end fixedly connected with electrically conducts bent plate, electrically conduct bent plate one end be the level setting and with the one end parallel and level of U-shaped plate fixedly connected with stationary contact plate, its other end bending and fixed connection are in the U-shaped plate one end of keeping away from the stationary contact plate.

Through adopting above-mentioned technical scheme, when moving contact and static contact switched on, the electric current flowed to electrically conductive bent plate from the one end flow direction of U shaped plate fixedly connected with stationary contact board to make the electric current round iron core a week, and then increased the magnetic field intensity in the magnetic field that produces, further increased electronic repulsion.

The invention is further configured to: and the U-shaped plate, the conductive curved plate and the static contact plate are provided with anti-electromagnetic wave interference shielding coatings on the surfaces.

Through adopting above-mentioned technical scheme, utilize anti-electromagnetic wave interference shielding coating to protect U-shaped board, electrically conductive bent plate and stationary contact not easily by the oxidation to utilize anti-electromagnetic wave interference shielding coating to prevent the influence of electromagnetic wave to U-shaped board, electrically conductive bent plate and stationary contact internal current.

The invention is further configured to: the conductive curved plate is provided with a through hole at one end far away from the U-shaped plate, and the surface of one end of the conductive curved plate close to the through hole is provided with a plurality of anti-skidding grooves.

Through adopting above-mentioned technical scheme, the through-hole can be used for the terminal that is used for fixed wire to pass, utilizes the coefficient of friction that antiskid groove increased electrically conductive bent plate, has increased the nut that is used for fixed wire on the terminal and has electrically conductive the frictional force between the bent plate, prevents that the nut on the terminal is not hard up.

The invention is further configured to: buffer structure is including rotating the carousel of connecting in the iron core, the cable other end is convoluteed in the carousel, the axis of rotation of carousel is perpendicular with the primary shaft, the carousel winding has the coil parallel rather than the axis of rotation, the coil is adjacent end to end.

By adopting the technical scheme, when the moving contact rotates towards the direction far away from the static contact structure so as to pull the inhaul cable, the inhaul cable pulls the turntable to rotate, and the turntable rotates so as to drive the coil to rotate; when moving contact and stationary contact structure separation, do not have the electric current in the U-shaped board, because the hysteresis iron core still has certain magnetism, the coil is at the magnetic field internal rotation of iron core and cutting magnetic sensitivity, produces the electric current in the coil, and then can produce in coil rotation direction opposite ampere force, utilizes ampere force to hinder the rotation of carousel, exerts pulling force to the cable, the impact force that produces when the buffering cable exerts pulling force to the moving contact to prevent that the impact force is too big and lead to the iron core breakage.

The invention is further configured to: and a coil spring is arranged between the rotary disc and the iron core, and the coil spring is compressed when the inhaul cable is uncoiled.

Through adopting above-mentioned technical scheme, when the moving contact contacted with the stationary contact structure, made the carousel rotate under the effect of coil spring to roll up the cable on the carousel again.

In conclusion, the invention has the following beneficial effects:

firstly, when the current passing through the short-circuiting device is overlarge, an electric repulsion force can be generated, and under the action of the electric repulsion force, the moving contact can repel the structure and rotate towards the direction far away from the static contact, so that an included angle is formed between the moving contact and the shell of the rotating shaft; the tripping device is triggered by overlarge current to enable the rotating shaft shell to rotate under the action of the torsion spring, so that the distance between the moving contact and the static contact is further increased, and the moving contact rotates downwards under the pulling force of the inhaul cable to automatically reset;

the two ends of the iron core are integrally formed with U-shaped magnetic conduction blocks, when the fixed contact contacts with the moving contact, current is generated in the U-shaped plate, a magnetic field is generated in the iron core under the action of the current, the direction of a magnetic induction line of the iron core is changed under the action of the U-shaped magnetic conduction blocks at the two ends of the iron core, and the magnetic induction line is concentrated between the end surfaces of the two U-shaped magnetic conduction blocks, so that the influence of the magnetic field generated by the two adjacent fixed contacts is reduced, the magnetic induction line is concentrated, the magnetic field intensity is increased, and the electric repulsion force is increased;

thirdly, the contact area between the moving contact and the fixed contact is increased by utilizing the moving contact plate, the pressure intensity between the moving contact and the fixed contact is reduced, and the moving contact is prevented from being damaged when the moving contact and the fixed contact are collided;

fourthly, when the moving contact rotates towards the direction far away from the static contact structure so as to pull the inhaul cable, the inhaul cable pulls the turntable to rotate, and the turntable rotates so as to drive the coil to rotate; when moving contact and stationary contact structure separation, do not have the electric current in the U-shaped board, because the hysteresis iron core still has certain magnetism, the coil is at the magnetic field internal rotation of iron core and cutting magnetic sensitivity, produces the electric current in the coil, and then can produce in coil rotation direction opposite ampere force, utilizes ampere force to hinder the rotation of carousel, exerts pulling force to the cable, the impact force that produces when the buffering cable exerts pulling force to the moving contact to prevent that the impact force is too big and lead to the iron core breakage.

Drawings

FIG. 1 is an exploded view of the present embodiment;

FIG. 2 is a sectional view of the present embodiment for showing the breaking mechanism;

FIG. 3 is a schematic structural diagram illustrating a repellent structure according to the present embodiment;

FIG. 4 is a schematic structural diagram illustrating a static contact structure according to the present embodiment;

FIG. 5 is a cross-sectional view of the present embodiment for showing a reset structure;

fig. 6 is an enlarged view of a portion a of fig. 5.

Reference numerals: 100. a breaking mechanism; 200. a static contact structure; 201. a static conductive plate; 202. an iron core; 203. a U-shaped plate; 204. a conductive curved plate; 205. a U-shaped groove; 206. a stationary contact plate; 207. a through hole; 208. an anti-slip groove; 300. a movable contact structure; 301. a rotating shaft housing; 302. a conductive splint; 303. a moving contact; 304. a repellent structure; 305. a buffer structure; 306. mounting grooves; 307. a first shaft; 308. a torsion spring; 309. pressing a plate; 310. a repulsion spring; 311. a second shaft; 312. a spring slot; 313. a rotating plate; 314. a cable; 315. a coil spring; 316. a support; 317. an inclined plate; 318. a turntable; 319. a coil; 320. threading holes; 321. a movable touch plate; 322. a reset structure; 401. a housing.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

A molded case circuit breaker, as shown in fig. 1, comprises a housing 401, a breaking mechanism 100 and a thermal magnetic release, wherein the breaking mechanism 100 and the thermal magnetic release are installed in the housing 401, and an actuating mechanism in the thermal magnetic release is used for contacting an actuating structure 300 and a static contact structure 200, so that the circuit breaker is conducted.

The movable contact structure 300 includes a rotating shaft housing 301, a conductive clamping plate 302 and a movable contact 303. The rotating shaft shell 301 is rotatably connected to the conductive clamping plate 302, and the movable contact 303 is hinged to the rotating shaft shell 301. The rotating shaft shell 301 is provided with a mounting groove 306, and the side wall of the mounting groove 306 is rotatably connected with a first shaft 307 which is horizontally arranged. The first shaft 307 is disposed through the conductive clamp plate 302 and rotatably connected thereto. The first shaft 307 is sleeved with a torsion spring 308, one end of the torsion spring 308 is fixedly connected to the conductive clamping plate 302, the other end of the torsion spring 308 is fixedly connected to the rotating shaft shell 301, and the rotating shaft shell 301 rotates counterclockwise under the torsion of the torsion spring 308. One end of the movable contact 303 is sleeved on the first shaft 307 and is rotatably connected with the first shaft 307, and one end of the movable contact 303, which is far away from the first shaft 307, extends out of the mounting groove 306. The moving contact 303 is kept away from the moving contact plate 321 that the one end fixedly connected with silver-copper alloy material of conducting plate 302 made, and the width of moving contact plate 321 is greater than the width of moving contact 303, utilizes the area of contact between moving contact plate 321 increase moving contact 303 and the fixed contact, reduces the pressure between the two, makes moving contact 303 damage when avoiding contradicting between the two. The rotating shaft shell 301 is provided with a repulsion structure 304 for driving the movable contact 303 to rotate. The repelling structure 304 drives the movable contact 303 to rotate in a direction opposite to the direction in which the torsion spring 308 drives the rotating shaft housing 301 to rotate. Under the action of the thermomagnetic trip, the rotating shaft shell 301 overcomes the elastic force of the torsion spring 308 to rotate counterclockwise, so that the movable contact 303 is abutted to the static contact structure 200. When the current passing through the circuit breaker is too large, the thermomagnetic release is triggered so as not to limit the rotating shaft shell 301 any more, so that the rotating shaft shell 301 rotates clockwise under the action of the torsion spring 308, and then the movable contact 303 is separated from the static contact structure 200, thereby achieving the purpose of breaking the circuit. The operating mechanism of the thermal magnetic release can adopt a transmission mechanism and a release mechanism of a molded case circuit breaker disclosed in chinese patent with publication number CN102386028B, so that the linkage shaft in the transmission mechanism and the release mechanism is rotatably connected to the rotating shaft housing 301 and is parallel to the first shaft 307.

The repulsion structure 304 comprises a pressing plate 309 hinged to the rotating shaft housing 301, a repulsion spring 310 driving the pressing plate 309 to rotate, and a second shaft 311 fixedly penetrating through the movable contact 303. The pressure plate 309 includes a rotating plate 313 and an inclined plate 317, which are integrally formed, and the rotating axis of the pressure plate 309 is arranged in parallel with the first shaft 307 and is located below the rotating plate 313. The inclined plate 317 is located above the rotating plate 313, and one end thereof remote from the rotating plate 313 is inclined in a direction away from the first shaft 307. The rotating shaft casing 301 is provided with a spring groove 312, one end of the repulsion spring 310 is disposed in the spring groove 312, and the other end abuts against the left side of the upper end of the rotating plate 313. When the movable contact 303 abuts against the bottom of the mounting groove 306, the second shaft 311 abuts against the right side of the upper end of the rotating plate 313; when the movable contact 303 rotates clockwise, the second shaft 311 pushes the pressing plate 309 to rotate against the elastic force of the repulsion spring 310, and the position of the interference with the pressing plate 309 moves from the rotating plate 313 to the inclined plate 317, so that the direction of the force applied by the pressing plate 309 to the second shaft 311 is changed, and the movable contact 303 rotates clockwise. The rotating shaft shell 301 is integrally formed with a limiting block, the limiting block is horizontally arranged, two ends of the limiting block are fixedly connected to the side wall of the mounting groove 306, and the limiting block is used for limiting the clockwise rotation angle of the moving contact 303. When the upper surface of the moving contact 303 abuts against the limiting block, the moving contact is positioned at the top dead center thereof; when the lower surface of the movable contact 303 abuts against the bottom wall of the mounting groove 306, the movable contact 303 is at the bottom dead center.

The static contact structure 200 includes a static conductive plate 201 and a core 202. The static conductive plate 201 comprises a U-shaped plate 203 and a conductive curved plate 204, one end of the U-shaped plate 203 is bent to form a U-shaped slot 205, and one end of the conductive curved plate 204 is fixedly connected to one end of the U-shaped plate 203. The iron core 202 is placed in the U-shaped slot 205, and the length direction of the iron core 202 is perpendicular to the current direction in the U-shaped plate 203. When the static conductive plate 201 is contacted with the movable contact 303, current is generated in the U-shaped plate 203, a magnetic field is generated in the iron core 202 under the action of the current, and the magnetic poles of the magnetic field are positioned at two ends of the iron core 202 in the length direction.

The U-shaped plate 203 is kept away from the one end welding of electrically conductive bent plate 204 and is had stationary contact plate 206, and stationary contact plate 206 is made for silver-copper alloy, so hardness is high and electric conductive property is good, thereby static conductive board 201 contradicts in stationary contact plate 206 and has realized switching on of stationary contact structure 200 and moving contact 303, utilizes stationary contact plate 206 protection U-shaped plate 203 to avoid passive contact 303 extrusion deformation.

The end of the conductive curved plate 204 far away from the U-shaped plate 203 is a plane and is flush with the end of the U-shaped plate 203 fixedly connected with the static contact plate 206, and the other end of the conductive curved plate 204 is bent and fixedly connected with the end of the U-shaped plate 203 far away from the static contact plate 206. The one end that electrically conducts bent plate 204 keeps away from U-shaped plate 203 is seted up the through-hole 207 that the terminal that supplies to be used for fixed wire passed, and for preventing that the nut on the terminal is not hard up, electrically conducts bent plate 204 and is close to the surface of through-hole 207 one end and has seted up a plurality of antiskid grooves 208, utilizes antiskid groove 208 to increase electrically conducts the coefficient of friction of bent plate 204, has increased the nut that is used for fixed wire on the terminal and the frictional force between electrically conducts bent plate 204.

The U-shaped plate 203 and the conductive curved plate 204 are integrally formed, so that the connection between the two is more stable. The surfaces of the U-shaped plate 203, the conductive curved plate 204 and the static contact plate 206 are provided with the electromagnetic wave interference prevention shielding coating, the U-shaped plate 203, the conductive curved plate 204 and the static contact plate 206 are protected by the electromagnetic wave interference prevention shielding coating and are not easily oxidized, and the electromagnetic wave interference prevention shielding coating is used for preventing the electromagnetic wave from influencing the current in the U-shaped plate 203, the conductive curved plate 204 and the static contact plate 206.

The movable contact structure 300 further includes a reset structure 322 for returning the movable contact 303 from the top dead center to the bottom dead center. The reset mechanism 322 includes a cable 314 and a cushioning mechanism 305. The buffer structure 305 has and is disposed at two ends of the iron core 202, the cable 314 is fixedly connected to one end of the movable contact 303 away from the first shaft 307, and the cable 314 is also fixedly connected to the buffer structure 305. One end of the movable contact 303 away from the first shaft 307 is provided with a threading hole 320, and the cable 314 passes through the threading hole 320 and both ends thereof are respectively and fixedly connected to the two buffer structures 305.

When the movable contact 303 is at the top dead center of the repulsion structure 304 and the rotating shaft shell 301 is still in the locking state of the thermomagnetic release, the cable 314 is in a tensioned state; when the thermomagnetic release is triggered and the rotating shaft shell 301 is not limited any more, the rotating shaft shell 301 rotates clockwise, so that the movable contact 303 has a tendency of continuing to rotate clockwise, the movable contact 303 is limited to continue to rotate under the pulling force of the pull cable 314, the rotating shaft shell 301 continues to rotate at the moment, so that the movable contact 303 and the rotating shaft shell 301 have a tendency of rotating relatively, the second shaft 311 slides to the rotating plate 313 from the inclined plate 317, then the movable contact 303 rotates counterclockwise relative to the rotating shaft shell 301 under the action of the elastic force of the spring 310, and the movable contact 303 is at a bottom dead center, so that the purpose of resetting is achieved.

The buffer structure 305 includes a bracket 316 fixedly coupled to the core 202 and a turntable 318 rotatably coupled to the bracket 316. The turntable 318 is wound with coils 319 parallel to its axis of rotation, the coils 319 being adjacent end to end. When wound around the turntable 318, the coil 319 passes through an end surface in the axial direction thereof. The coils 319 are three in number and are axially disposed about the axis of rotation of the turntable 318. The cable 314 is wound around the turntable 318. When the movable contact 303 rotates in a direction away from the stationary contact structure 200 to pull the cable 314, the cable 314 pulls the turntable 318 to rotate, and the turntable 318 rotates to drive the coil 319 to rotate; when the moving contact 303 is separated from the stationary contact structure 200, no current flows in the U-shaped plate 203, because the hysteresis core 202 still has certain magnetism, the coil 319 rotates in the magnetic field of the core 202 and cuts the magnetic induction, current flows in the coil 319, and then an ampere force in the opposite rotation direction of the coil 319 is generated, the rotation of the turntable 318 is obstructed by the ampere force, a pulling force is applied to the cable 314, and an impact force generated when the pulling force is applied to the moving contact by the cable 314 is buffered, so that the iron core 202 is prevented from being broken due to the overlarge impact force. The bracket 316 is fixedly sleeved with a coil spring 315, and the coil spring 315 is compressed when the pull cable 314 is uncoiled. When the movable contact 303 is in contact with the static contact structure 200, the rotating disc 318 is rotated under the action of the coil spring 315, so that the cable 314 is rewound on the rotating disc 318.

The implementation principle of the embodiment is as follows: when the current passing through the circuit breaker is too large, the tripper is triggered so as not to limit the rotating shaft shell 301 any more, the rotating shaft shell 301 rotates clockwise under the action of the torsion spring 308, and then the movable contact 303 is separated from the static contact structure 200, so that the purpose of breaking a circuit is achieved. When the current is too large, the magnetic field generated in the iron core 202 is increased, and the electric repulsive force applied to the moving contact 303 in the magnetic field is also increased, so that the moving contact rotates clockwise. When the moving contact 303 rotates clockwise, the second shaft 311 pushes the pressing plate 309 to rotate against the elastic force of the repulsion spring 310, and the interference position of the second shaft 311 and the pressing plate 309 moves from the rotating plate 313 to the inclined plate 317, so that the direction of the force applied by the pressing plate 309 to the second shaft 311 is changed, and the moving contact 303 rotates clockwise to the top dead center. When the current through the circuit breaker is too large, the tripper can also trigger so as not to limit the rotating shaft shell 301 any more, so that the rotating shaft shell 301 rotates clockwise under the action of the torsion spring 308, the movable contact 303 has the trend of continuing to rotate clockwise, under the pulling force of the pull cable 314, the movable contact 303 is limited to continue to rotate, the rotating shaft shell 301 continues to rotate at the moment, so that the movable contact 303 and the rotating shaft shell 301 have the trend of rotating relatively, the second shaft 311 slides to the rotating plate 313 through the inclined plate 317, then the movable contact 303 is driven to rotate anticlockwise relative to the rotating shaft shell 301 under the action of the elastic force of the spring 310, the movable contact 303 is at the bottom dead center, and the.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. A molded case circuit breaker, characterized in that: the magnetic trip comprises a shell (401), a breaking mechanism (100) and a thermomagnetic trip, wherein the breaking mechanism (100) is arranged in the shell (401), the breaking mechanism (100) comprises a moving contact structure (300), a static contact structure (200) and a reset structure (322), the moving contact structure (300) comprises a rotating shaft shell (301) and a conductive clamping plate (302) fixedly connected to the shell (401), the rotating shaft shell (301) is rotatably connected to the conductive clamping plate (302), a torsion spring (308) for driving the rotating shaft shell (301) to rotate is arranged between the conductive clamping plate (302) and the rotating shaft shell (301), the conductive clamping plate (302) is hinged with a moving contact (303), the rotating shaft shell (301) is provided with a repulsion structure (304) for driving the moving contact (303) to rotate and to be abutted against the rotating shaft shell (301), the rotating direction of the moving contact (303) driven by the repulsion structure (304) is opposite to the rotating direction of driving the rotating shaft shell (301) driven by the, the length of the moving contact (303) is greater than the distance between the rotating axis and the static contact structure (200), the reset structure (322) comprises a pull cable (314) and a buffer structure (305), one end, far away from the rotating axis, of the moving contact (303) is provided with a threading hole (320), the pull cable (314) penetrates through the threading hole (320), and two ends of the pull cable are fixedly connected with the buffer structure (305) respectively.

2. A molded case circuit breaker according to claim 1, characterized in that: one end, far away from the conductive clamping plate (302), of the moving contact (303) is fixedly connected with a moving contact plate (321) made of metal, and the width of the moving contact plate (321) is larger than that of the moving contact (303).

3. A molded case circuit breaker according to claim 2, wherein: the static contact structure (200) includes U-shaped plate (203), the crooked U-shaped groove (205) that forms of U-shaped plate (203) one end, be equipped with iron core (202) in U-shaped groove (205), iron core (202) are along the both ends fixedly connected with U-shaped magnetic conduction piece of U-shaped plate (203) width, two U-shaped magnetic conduction piece one end difference fixed connection is in the both ends terminal surface of iron core (202), and its other end is close to each other.

4. A molded case circuit breaker according to claim 3, wherein: and a static contact plate (206) made of silver-copper alloy is fixedly connected to the outer wall of one end of the U-shaped plate (203), which is far away from the U-shaped groove (205).

5. A molded case circuit breaker according to claim 4, characterized in that: u-shaped board (203) other end fixedly connected with electrically conducts bent plate (204), electrically conduct bent plate (204) one end be the level setting and with the one end parallel and level of U-shaped board (203) fixedly connected with stationary contact board (206), its other end bending and fixed connection are in U-shaped board (203) the one end of keeping away from stationary contact board (206).

6. A molded case circuit breaker according to claim 5, wherein: and electromagnetic wave interference preventing shielding coatings are arranged on the surfaces of the U-shaped plate (203), the conductive curved plate (204) and the static contact plate (206).

7. A molded case circuit breaker according to claim 6, wherein: the conducting curved plate is characterized in that a through hole (207) is formed in one end, away from the U-shaped plate (203), of the conducting curved plate (204), and a plurality of anti-skidding grooves (208) are formed in the surface of one end, close to the through hole (207), of the conducting curved plate (204).

8. A molded case circuit breaker according to claim 7, wherein: the buffer structure (305) comprises a rotating disc (318) which is rotatably connected to the iron core (202), two ends of the inhaul cable (314) are wound on the rotating disc (318), the rotating axis of the rotating disc (318) is perpendicular to the first shaft (307), coils (319) parallel to the rotating axis of the rotating disc (318) are wound on the rotating disc (318), and the coils (319) are adjacent end to end.

9. A molded case circuit breaker according to claim 8, wherein: a coil spring (315) is arranged between the rotary disc (318) and the iron core (202), and the coil spring (315) is compressed when the inhaul cable (314) is uncoiled.