CN116741601A - System capable of resetting after locking moving and static contacts of molded case circuit breaker - Google Patents

Abstract

The invention relates to a resettable system for a molded case circuit breaker after a moving contact and a fixed contact are locked. The invention comprises a moving contact structure and a fixed contact structure, wherein the moving contact structure comprises: the first end of the moving contact connecting arm is provided with a moving contact; the second end of the movable contact connecting arm is connected with the rotating shaft; the reset slide seat drives the reset slide seat to slide up and down when the rotating shaft rotates; the static contact structure comprises: a sliding bracket with a first locking head; the fixed contact assembly comprises a fixed contact connecting arm, wherein the fixed contact connecting arm comprises a first rotating end, a second rotating end and a pulling end arranged between the first rotating end and the second rotating end, the first rotating end of the fixed contact connecting arm is provided with a fixed contact matched with the moving contact and a second locking head, and the second rotating end of the fixed contact connecting arm is rotationally connected with the connecting plate. According to the invention, after the circuit breaker encounters a short circuit and high current, the static contact can be quickly separated and locked, and reset can be performed, so that the short circuit breaking capacity of the circuit breaker is improved.

Description

System capable of resetting after locking moving and static contacts of molded case circuit breaker

Technical Field

The invention relates to the technical field of circuit breakers, in particular to a resettable system used for a molded case circuit breaker after a moving contact and a fixed contact are locked.

Background

The plastic case circuit breaker is a mechanical switching device capable of switching on, carrying and breaking a current under normal circuit conditions, and switching on, carrying for a certain time and breaking a current under specified abnormal conditions (such as a short circuit condition), and generally uses a plastic insulator as a housing of the device.

When the existing circuit breaker is in a large-current short circuit, the static contact cannot be completely separated and locked, the phenomenon that an electric arc burns and damages the silver point of the static contact is easy to occur, and the circuit breaker cannot be quickly reset after the static contact is locked, so that the short circuit breaking capacity of the circuit breaker is limited.

Disclosure of Invention

Therefore, the invention aims to solve the technical problems that a circuit breaker cannot be completely separated and locked with a fixed contact when a large-current short circuit occurs and cannot be quickly reset after the fixed contact is locked in the prior art, and provides a system capable of being reset after the fixed contact of a molded case circuit breaker is locked, so that the fixed contact can be quickly separated and locked after the circuit breaker encounters a short circuit large current, and the reset can be performed.

In order to solve the technical problems, the invention provides a resettable system after locking a movable contact and a fixed contact of a molded case circuit breaker, which comprises a movable contact structure and a fixed contact structure;

the moving contact structure comprises:

the movable contact connecting arm comprises a first end and a second end which are oppositely arranged, and the first end of the movable contact connecting arm is provided with a movable contact;

the second end of the movable contact connecting arm is connected with the rotating shaft and rotates around the rotating axis of the rotating shaft;

the reset slide seat drives the reset slide seat to slide up and down when the rotating shaft rotates;

the static contact structure comprises:

a connecting plate;

the sliding bracket is arranged at the lower side of the reset sliding seat, is slidably arranged on the connecting plate and is provided with a first locking head;

the fixed contact assembly comprises a fixed contact connecting arm, wherein the fixed contact connecting arm comprises a first rotating end, a second rotating end and a pulling end, the first rotating end and the second rotating end are oppositely arranged, the pulling end is arranged between the first rotating end and the second rotating end and is elastically connected with the sliding support, the first rotating end of the fixed contact connecting arm is provided with a fixed contact matched with the moving contact and a second locking head matched with the first locking head in a locking manner, and the second rotating end of the fixed contact connecting arm is rotationally connected with the connecting plate;

after the fixed contact and the movable contact are mutually exclusive, the fixed contact connecting arm can rotate around the second rotating end, so that the second locking head is in contact with the first locking head, the sliding support slides along the connecting plate, and the second locking head is matched with the first locking head for locking; when unlocking is carried out, the rotating shaft can push the reset sliding seat to slide, and the sliding support is driven to slide along the connecting plate continuously until the first locking head and the second locking head are separated and unlocked.

In one embodiment of the invention, the upper end of the sliding support is provided with a first sliding surface, the lower end of the reset slide seat is provided with a first pushing surface in sliding contact fit with the first sliding surface, and when the reset slide seat moves downwards relative to the sliding support, the sliding contact fit between the first sliding surface and the first pushing surface is converted into horizontal movement of the sliding support.

In one embodiment of the invention, the upper end of the reset slide seat is provided with a second sliding surface, the rotating shaft is provided with a second pushing surface in sliding contact with the second sliding surface, and when the moving contact rotates towards the direction approaching to the fixed contact, the second sliding surface is in sliding contact with the second pushing surface and enables the reset slide seat to move downwards.

In one embodiment of the present invention, the reset slide comprises a slide plate and slide blocks respectively arranged at two ends of the slide plate, a spring is arranged between the slide blocks and the slide plate, the rotating shaft comprises an eccentric block matched with the slide blocks, the slide blocks are configured with the first pushing surface and the second sliding surface, and the eccentric block is configured with the second pushing surface.

In one embodiment of the present invention, the first locking head includes a first hook portion, the first hook portion has a first contact end and a first locking end engaged with the first contact end, the second locking head includes a second hook portion, the second hook portion has a second contact end and a second locking end engaged with the second contact end, the first contact end can be slidingly contacted with the second contact end to be converted into a translational movement of the sliding bracket along the sliding bracket, so that after the sliding bracket slides to a predetermined position, the first locking end and the second locking end are locked by hooking.

In one embodiment of the invention, the static contact structure further comprises a static contact connecting arm rotating shaft, a first positioning shaft, a second positioning shaft, a static contact tension spring and a sliding support tension spring, wherein the sliding support comprises a base and two mounting plates extending to two sides of one end of the base, the second locking head is formed at the upper end of the base, each mounting plate comprises a connecting column arranged on the outer side of the connecting column and a sliding groove arranged on one side of the connecting column, the second rotating end of the static contact connecting arm is connected with the connecting plate through the static contact connecting arm rotating shaft, the first positioning shaft penetrates through the pulling end of the static contact connecting arm, and two ends of the second positioning shaft are respectively arranged in the sliding groove in a penetrating mode and the sliding support tension spring is arranged between the second positioning shaft and the connecting column.

In one embodiment of the invention, the static contact structure further comprises a static contact protective sleeve, the static contact protective sleeve is sleeved on the side, close to the static contact, of the static contact connecting arm, the lower end of the static contact protective sleeve is provided with the second locking head, the static contact protective sleeve further comprises a bottom plate arranged at the bottom end of the static contact connecting arm and two baffle plates which extend from the bottom plate and are positioned at two side ends of the static contact connecting arm, the first positioning shaft penetrates through the two baffle plates and the pulling end, one end of each baffle plate is provided with a limiting notch, and the static contact connecting arm further penetrates through a limiting shaft penetrating through each limiting notch of the two baffle plates.

In one embodiment of the invention, the static contact structure further comprises a protective cover and a protective cover rotating shaft, the protective cover comprises rotating arms arranged on the outer sides of the two baffle plates respectively, a cover body connected with the two rotating arms and positioned on the upper sides of the static contact, and an actuating rod connected with the two rotating arms, the cover body is provided with a yielding channel, the actuating rod is provided with a third contact end, the static contact connecting arm is provided with a fourth contact end matched with the third contact end for sliding, the third contact end and the fourth contact end are inclined planes, the base is provided with an ear seat corresponding to the rotating arms, and the protective cover rotating shaft is arranged on the two rotating arms and the two ear seats in a penetrating mode.

In one embodiment of the invention, the connecting plate is provided with a rotating shaft seat matched with the rotating shaft of the fixed contact connecting arm, two ends of the rotating shaft of the fixed contact connecting arm are limited by the mounting plate, the rotating shaft seat is provided with a yielding groove used for rotating the second rotating end of the fixed contact connecting arm, and one end of the connecting plate, which is far away from the rotating shaft seat, is provided with a fixed contact bracket positioned beside the fixed contact.

In one embodiment of the present invention, the static contact structure further includes a magnetism increasing sheet disposed between the connection plate and the bracket.

Compared with the prior art, the technical scheme of the invention has the following advantages:

according to the resettable system after locking the movable contact of the molded case circuit breaker, when the circuit breaker passes through a short circuit and high current, electromagnetic repulsion force is generated between the movable contact and the fixed contact and is quickly repelled, the connecting arm of the fixed contact can be quickly rotated in the direction away from the movable contact, the fixed contact is quickly locked, an electric arc can be quickly and effectively cut off, the silver point of the fixed contact is prevented from being repeatedly burned by the electric arc, the silver point of the movable contact is protected, and the breaking capacity is improved; when the circuit breaker is required to be switched on again, the rotating shaft can push the reset sliding seat to slide and drive the sliding support to slide so as to unlock. The invention solves the problems that the circuit breaker cannot completely repel and lock the static contact and cannot reset after locking, thereby improving the short circuit breaking capacity of the circuit breaker.

Drawings

In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings.

Fig. 1 is a schematic front view of the overall structure of the resettable system of the present invention.

Fig. 2 is a side view schematic of the overall structure of the resettable system of the present invention.

Fig. 3 is an exploded view of the static contact structure of the present invention.

Fig. 4 is a schematic diagram of the overall structure of the static contact structure of the present invention.

Fig. 5 is a schematic view of a part of the structure of the static contact structure of the present invention.

Fig. 6 is a schematic structural view of a stationary contact protective sleeve according to the present invention.

Fig. 7 is a schematic structural view of the stationary contact assembly of the present invention.

Fig. 8 is a schematic structural view of the protective cover of the present invention.

Fig. 9 is a schematic structural view of the sliding bracket of the present invention.

Fig. 10 is a schematic structural view of the connection plate of the present invention.

Fig. 11 is a schematic view of the static contact structure of the present invention in an initial state.

Fig. 12 is a sectional view of the structure of the static contact structure of the present invention in a state of being separated.

Fig. 13 is an enlarged schematic view at B in fig. 12.

Fig. 14 is a schematic diagram of the closing state of the resettable system of the present invention.

Fig. 15 is a schematic view of the stationary contact lock state of the resettable system of the present invention.

Fig. 16 is a schematic diagram of an unlock reset transient state of the resettable system of the present invention.

FIG. 17 is a schematic diagram of a combination of multiple resettable systems of the present invention.

Description of the specification reference numerals:

100. a moving contact structure; 110. a moving contact connecting arm; 111. a moving contact; 120. a push shaft rotating shaft; 121. an eccentric block; 121a, a second pushing surface; 130. resetting the slide seat; 131. a slide plate; 132. a slide block; 132a, a first pushing surface; 132b, a second sliding surface; 133. a spring;

200. a stationary contact structure; 1. a connecting plate; 11. a rotating shaft seat; 12. a relief groove;

2. a sliding support; 21. a first locking head; 211. a first hook portion; 211a, a first contact end; 211b, a first locking end; 25. a base; 251. an ear seat; 26. a mounting plate; 26a, a first sliding surface; 261. a connecting column; 262. a chute;

3. a stationary contact assembly; 31. a fixed contact connecting arm; 31a, a first rotating end; 31b, a second rotating end; 31c, a pulling end; 31d, fourth contact ends; 32. a stationary contact; 33. a second locking head; 331. a second hook portion; 331a, second contact ends; 331b, a second locking end;

4. a protective cover; 41. a rotating arm; 42. a cover body; 43. a protective cover rotating shaft; 44. an actuating lever; 44a, a third contact end; 45. a yielding channel;

5. a static contact protective sleeve; 51. a bottom plate; 52. a baffle; 521. limiting notch; 53. a limiting shaft;

61. a fixed contact rotating shaft; 62. a first positioning shaft; 63. a second positioning shaft; 64. a fixed contact tension spring; 65. a sliding bracket tension spring;

7. a static contact support;

8. a magnetic increasing sheet;

9. and a flexible connecting wire.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to be limiting, so that those skilled in the art will better understand the invention and practice it.

In the present invention, if directions (up, down, left, right, front and rear) are described, they are merely for convenience of description of the technical solution of the present invention, and do not indicate or imply that the technical features must be in a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the present invention, "a plurality of" means one or more, and "a plurality of" means two or more, and "greater than", "less than", "exceeding", etc. are understood to not include the present number; "above", "below", "within" and the like are understood to include this number. In the description of the present invention, the description of "first" and "second" if any is used solely for the purpose of distinguishing between technical features and not necessarily for the purpose of indicating or implying a relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the present invention, unless clearly defined otherwise, terms such as "disposed," "mounted," "connected," and the like should be construed broadly and may be connected directly or indirectly through an intermediate medium, for example; the connecting device can be fixedly connected, detachably connected and integrally formed; can be mechanically connected, electrically connected or capable of communicating with each other; may be a communication between two elements or an interaction between two elements. The specific meaning of the words in the invention can be reasonably determined by a person skilled in the art in combination with the specific content of the technical solution.

Referring to fig. 1 to 3, the resettable system after locking a moving contact of a molded case circuit breaker according to the present invention includes a moving contact structure 100 and a fixed contact structure 200;

the moving contact structure 100 includes:

the movable contact connecting arm 110 comprises a first end and a second end which are oppositely arranged, and the first end of the movable contact connecting arm 110 is provided with a movable contact 111;

a rotating shaft 120, wherein the second end of the moving contact connecting arm 110 is connected to the rotating shaft 120 and rotates around the rotation axis of the rotating shaft 120;

a reset slide 130, which drives the reset slide 130 to slide up and down when the rotating shaft 120 rotates;

the stationary contact structure 200 includes:

a connecting plate 1;

a sliding bracket 2, which is arranged at the lower side of the reset slide 130, is slidably arranged on the connecting plate 1, and is provided with a first locking head 21;

the fixed contact assembly 3 comprises a fixed contact connecting arm 31, the fixed contact connecting arm 31 comprises a first rotating end 31a and a second rotating end 31b which are oppositely arranged, and a pulling end 31c which is arranged between the first rotating end 31a and the second rotating end 31b and is elastically connected with the sliding bracket 2, the first rotating end 31a of the fixed contact connecting arm 31 is provided with a fixed contact 32 matched with the movable contact 111 and a second locking head 33 matched with the first locking head 21 in a locking way, and the second rotating end 31b of the fixed contact connecting arm 31 is rotatably connected with the connecting plate 1;

wherein, when the fixed contact 32 and the movable contact 111 are separated from each other, the fixed contact connecting arm 31 can rotate around the second rotating end 31b, so that the second locking head 33 contacts with the first locking head 21 and the sliding bracket 2 slides along the connecting plate 1, and the second locking head 33 is locked with the first locking head 21 in a matching way; when unlocking, the rotating shaft 120 can push the reset slide seat 130 to slide, so as to drive the sliding bracket 2 to slide along the connecting plate 1 continuously until the first locking head 21 and the second locking head 33 are separated and unlocked.

Through the arrangement, after the circuit breaker passes through a short circuit and high current, electromagnetic repulsion force is generated between the fixed contact 32 and the moving contact 111 and is quickly repelled, and the fixed contact connecting arm 31 can be quickly rotated towards the direction away from the moving contact 111, and the fixed contact 32 is quickly locked. The rotating shaft 120 can push the reset slide 130 to slide, and drive the sliding bracket 2 to slide, so as to unlock.

With continued reference to fig. 1 to 3, specifically, the upper end of the sliding support 2 is provided with a first sliding surface 26a, the lower end of the reset slide 130 is provided with a first pushing surface 132a in sliding contact with the first sliding surface 26a, and when the reset slide 130 moves downward relative to the sliding support 2, the sliding contact between the first sliding surface 26a and the first pushing surface 132a is converted into horizontal movement of the sliding support 2. In this embodiment, the first sliding surface 26a and the second sliding surface 132b are engaged by a beveled contact.

As shown in fig. 1 to 3, specifically, the upper end of the reset slide 130 is provided with a second sliding surface 132b, the rotating shaft 120 is provided with a second pushing surface 121a in sliding contact with the second sliding surface 132b, and when the moving contact 111 rotates in a direction approaching to the fixed contact 32, the second sliding surface 132b is in sliding contact with the second pushing surface 121a and moves the reset slide 130 downward. In the present embodiment, the second sliding surface 132b and the second pushing surface 121a are both arc surfaces or a combination structure of arc surfaces and inclined surfaces, and the present invention is not particularly limited as long as the above-mentioned effects can be achieved.

With continued reference to fig. 1 to 3, specifically, the reset slide 130 includes a slide 131 and slide blocks 132 respectively disposed at two ends of the slide 131, a spring 133 is disposed between the slide blocks 132 and the slide 131, the rotating shaft 120 includes an eccentric block 121 matched with the slide blocks 132, the slide blocks 132 are configured with a first pushing surface 132a and a second sliding surface 132b, and the eccentric block 121 is configured with a second pushing surface 121a. In this embodiment, the eccentric blocks 121 extend along two sides of the axis of the rotating shaft 120, and the rotating axis of the rotating shaft 120 is located at one side of the second end of the moving contact connecting arm 110.

Referring to fig. 6 and 9, specifically, the first locking head 21 includes a first hook 211, the first hook 211 has a first contact end 211a and a first locking end 211b engaged with the first contact end 211a, the second locking head 33 includes a second hook 331, the second hook 331 has a second contact end 331a and a second locking end 331b engaged with the second contact end, and the first contact end 211a can be slidably contacted with the second contact end 331a to be translated into the sliding motion of the sliding bracket 2, so that the first locking end 211b and the second locking end 331b are locked by hooking after the sliding bracket 2 slides to a predetermined position. In this embodiment, the first contact end 211a and the second contact end 331a each include an arc surface and/or an inclined surface, so that the sliding bracket 2 can slide along the connecting plate 1 when the first contact end 211a and the second contact end 331a are slidably engaged with each other until the first locking head 21 and the second locking head 33 are engaged with each other.

With continued reference to fig. 3, specifically, the fixed contact structure 200 further includes a rotating shaft of the fixed contact connecting arm 31, a first positioning shaft 62, a second positioning shaft 63, a fixed contact tension spring 64, and a sliding support tension spring 65, the sliding support 2 includes a base 25 and two mounting plates 26 extending on two sides of one end of the base 25, the upper end of the base 25 forms the second locking head 33, each mounting plate 26 includes a connecting post 261 disposed on the outer side thereof and a sliding groove 262 disposed on one side of the connecting post 261, a second rotating end 31b of the fixed contact connecting arm 31 is connected to the connecting plate 1 through the rotating shaft of the fixed contact connecting arm 31, the first positioning shaft 62 is disposed through a pulling end 31c of the fixed contact connecting arm 31, and two ends of the second positioning shaft 63 are respectively disposed through the sliding groove 262 and are disposed between the sliding support tension spring 65 and the connecting post 261.

Referring to fig. 6, specifically, the static contact structure 200 further includes a static contact protection sleeve 5, the static contact protection sleeve 5 is sleeved on the side of the static contact connection arm 31, which is close to the static contact 32, the second locking head 33 is configured at the lower end of the static contact protection sleeve 5, the static contact protection sleeve 5 further includes a bottom plate 51 disposed at the bottom end of the static contact connection arm 31, and two baffles 52 extending from the bottom plate 51 and located at two side ends of the static contact connection arm 31, the first positioning shaft 62 is disposed through the two baffles 52 and the pulling end 31c, a limiting notch 521 is disposed at one end of the baffle 52, and the static contact connection arm 31 is further disposed through a limiting shaft 53 passing through the respective limiting notch 521 of the two baffles 52.

Referring to fig. 3 and 8, specifically, the stationary contact structure 200 further includes a protective cover 4 and a protective cover rotating shaft 43, the protective cover 4 includes a rotating arm 41 disposed at the outer sides of the two baffles 52, a cover 42 connected to the two rotating arms 41 and disposed at the upper sides of the stationary contact 32, and an actuating rod 44 connected to the two rotating arms 41, the cover 42 is provided with a yielding channel 45, the actuating rod 44 is provided with a third contact end 44a, the stationary contact connecting arm 31 is provided with a fourth contact end 31d sliding in cooperation with the third contact end 44a, the third contact end 44a and the fourth contact end 31d are inclined surfaces, the base 25 is provided with an ear socket 251 disposed corresponding to the rotating arm 41, and the protective cover rotating shaft 43 is disposed through the two rotating arms 41 and the ear socket 251.

Through the above arrangement, in the initial state, the fixed contact 32 extends out of the cover 42 from the upper side, when the fixed contact connecting arm 31 rotates around the second rotating end 31b, the fixed contact connecting arm 31 and the actuating rod 44 are in sliding fit with each other through the third contact end 44a and the fourth contact end 31d, so that the protective cover 4 rotates, and the fixed contact 32 enters the cover 42 through the abdication channel 45, so as to perform arc extinction, rapidly and effectively cut off the arc, avoid the repeated burning loss of the silver points of the fixed contact 32 and the silver points of the moving contact 111, protect the silver points of the moving contact, and improve the breaking capacity. In this embodiment, the third contact end 44a and the fourth contact end 31d are both inclined surfaces.

Referring to fig. 10, specifically, the connection board 1 is provided with a rotating shaft seat 11 that is matched with the rotating shaft of the fixed contact connection arm 31, two ends of the rotating shaft of the fixed contact connection arm 31 are limited by the mounting plate 26, the rotating shaft seat 11 is provided with a yielding groove 12 that is used for rotating the second rotating end 31b of the fixed contact connection arm 31, and a fixed contact bracket 7 that is located beside the fixed contact 32 is installed at one end of the connection board 1 away from the rotating shaft seat 11.

Referring to fig. 3, specifically, the static contact structure 200 further includes a magnetic increasing sheet 8 disposed between the connection plate 1 and the bracket, so as to further improve electromagnetic repulsive force between the static contact 32 and the moving contact 111.

In this embodiment, each of the above components (including the flexible connection wire 9) is installed in the housing of the molded case circuit breaker, the reset slide 130 can slide up and down along the side wall of the housing, or may be separately provided with a structure such as a sliding support, and two ends of the rotating shaft 120 are rotatably connected to the housing, and a plurality of reset systems may be provided on the same housing, as shown in fig. 17.

Referring to fig. 12 to 16, in the closing state of the circuit breaker, the stationary contact 32 extends out of the protection cover 4 and is in contact engagement with the movable contact 111. After the circuit breaker passes the short-circuit heavy current, electromagnetic repulsion force F is generated between the fixed contact 32 and the moving contact 111, so that the fixed contact connecting arm 31 rotates towards the direction away from the moving contact 111 (anticlockwise direction), meanwhile, the moving contact connecting arm 110 rotates clockwise around the rotation axis of the rotation shaft 120, so that the second locking head 33 contacts with the first locking head 21, and the sliding bracket 2 slides on the connecting plate 1 along the left horizontal direction through the sliding fit between the first contact end 211a and the second contact end 331a until the first locking head 21 and the second locking head 33 are hooked and locked, at this time, the fixed contact connecting arm 31 has a clockwise rotation trend through the fixed contact tension spring 64, and meanwhile, the protective cover 4 completely covers the fixed contact 32, so that the purpose of completely cutting off an arc is achieved. When the broken circuit breaker needs to be continuously switched on, the circuit breaker mechanism is operated to enable the movable contact connecting arm 110 to rotate anticlockwise, the reset slide seat 130 is pushed to slide downwards through the rotating shaft 120, the reset slide seat 130 continuously moves the sliding support 2 along the left horizontal direction until the first locking head 21 and the second locking head 33 are separated and unlocked, and reset is completed.

Finally, it should be noted that the above-mentioned embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications and equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and all such modifications and equivalents are intended to be encompassed in the scope of the claims of the present invention.

Claims (10)

1. The resettable system after locking a movable contact and a fixed contact of a molded case circuit breaker is characterized by comprising a movable contact structure (100) and a fixed contact structure (200);

the moving contact structure (100) includes:

the movable contact connecting arm (110) comprises a first end and a second end which are oppositely arranged, and the first end of the movable contact connecting arm (110) is provided with a movable contact (111);

a rotating shaft (120), wherein the second end of the movable contact connecting arm (110) is connected to the rotating shaft (120) and rotates around the rotating axis of the rotating shaft (120);

the reset slide seat (130) drives the reset slide seat (130) to slide up and down when the rotating shaft (120) rotates;

the stationary contact structure (200) comprises:

a connection plate (1);

the sliding support (2) is arranged at the lower side of the reset sliding seat (130), is slidably arranged on the connecting plate (1) and is provided with a first locking head (21);

the fixed contact assembly (3) comprises a fixed contact connecting arm (31), wherein the fixed contact connecting arm (31) comprises a first rotating end (31 a) and a second rotating end (31 b) which are oppositely arranged, and a pulling end (31 c) which is arranged between the first rotating end (31 a) and the second rotating end (31 b) and is elastically connected with the sliding support (2), the first rotating end (31 a) of the fixed contact connecting arm (31) is provided with a fixed contact (32) matched with the moving contact (111) and a second locking head (33) locked and matched with the first locking head (21), and the second rotating end (31 b) of the fixed contact connecting arm (31) is rotatably connected with the connecting plate (1);

when a large current short circuit occurs, an electromagnetic repulsive force is generated between the movable contact and the fixed contact of the molded case circuit breaker, after the fixed contact (32) and the movable contact (111) are mutually repelled, the fixed contact connecting arm (31) can rotate around the second rotating end (31 b) so as to enable the second locking head (33) to be in contact with the first locking head (21) and enable the sliding bracket (2) to slide along the connecting plate (1), and the second locking head (33) is matched with the first locking head (21) for locking; when unlocking is carried out, the rotating shaft (120) can push the reset sliding seat (130) to slide, and the sliding support (2) is driven to slide along the connecting plate (1) continuously until the first locking head (21) and the second locking head (33) are separated and unlocked.

2. The system for resetting a movable contact and a static contact of a molded case circuit breaker after locking according to claim 1, wherein a first sliding surface (26 a) is arranged at the upper end of the sliding support (2), a first pushing surface (132 a) matched with the first sliding surface (26 a) in a sliding contact manner is arranged at the lower end of the resetting slide seat (130), and when the resetting slide seat (130) moves downwards relative to the sliding support (2), the sliding contact matching of the first sliding surface (26 a) and the first pushing surface (132 a) is converted into horizontal movement of the sliding support (2).

3. The system for resetting the movable contact of the molded case circuit breaker after locking according to claim 2, wherein a second sliding surface (132 b) is arranged at the upper end of the resetting slide seat (130), a second pushing surface (121 a) matched with the second sliding surface (132 b) in a sliding contact manner is arranged on the rotating shaft (120), and when the movable contact (111) rotates towards the direction approaching to the fixed contact (32), the second sliding surface (132 b) and the second pushing surface (121 a) are in sliding contact engagement and enable the resetting slide seat (130) to move downwards.

4. A resettable system after locking a moving contact and a static contact of a molded case circuit breaker according to claim 3, wherein the reset slide (130) comprises a slide plate (131) and slide blocks (132) respectively arranged at two ends of the slide plate (131), a spring (133) is arranged between the slide blocks (132) and the slide plate (131), the rotating shaft (120) comprises an eccentric block (121) matched with the slide blocks (132), the slide blocks (132) are provided with a first pushing surface (132 a) and a second pushing surface (132 b), and the eccentric block (121) is provided with a second pushing surface (121 a).

5. The system as claimed in claim 1, wherein the first locking head (21) comprises a first hook (211), the first hook (211) has a first contact end (211 a) and a first locking end (211 b) connected to the first contact end (211 a), the second locking head (33) comprises a second hook (331), the second hook (331) has a second contact end (331 a) and a second locking end (331 b) connected to the second contact end, and the first contact end (211 a) can be slidingly contacted with the second contact end (331 a) to be translated into the sliding bracket (2), so that the first locking end (211 b) and the second locking end (331 b) are locked by hooking after the sliding bracket (2) slides to a predetermined position.

6. The system for locking and resetting a movable contact of a molded case circuit breaker according to claim 1, wherein the fixed contact structure (200) further comprises a rotating shaft of a fixed contact connecting arm (31), a first positioning shaft (62), a second positioning shaft (63), a fixed contact tension spring (64) and a sliding support tension spring (65), the sliding support (2) comprises a base (25) and two mounting plates (26) extending to two sides of one end of the base (25), the second locking head (33) is formed at the upper end of the base (25), each mounting plate (26) comprises a connecting post (261) arranged on the outer side of the mounting plate and a sliding groove (262) arranged on one side of the connecting post (261), a second rotating end (31 b) of the fixed contact connecting arm (31) is connected to the fixed contact connecting arm (1) through the rotating shaft of the fixed contact connecting arm (31), the first positioning shaft (62) is arranged on a pulling end (31 c) of the fixed contact connecting arm (31) in a penetrating manner, and the second positioning shaft (63) is respectively provided with the sliding support (262) and the sliding support (65) is arranged between the sliding posts.

7. The system for locking and resetting a movable contact of a molded case circuit breaker according to claim 1, wherein the fixed contact structure (200) further comprises a fixed contact protection sleeve (5), the fixed contact protection sleeve (5) is sleeved on the side of the fixed contact connection arm (31) close to the fixed contact (32), the second locking head (33) is formed at the lower end of the fixed contact protection sleeve (5), the fixed contact protection sleeve (5) further comprises a bottom plate (51) arranged at the bottom end of the fixed contact connection arm (31) and two baffle plates (52) extending from the bottom plate (51) and located at two side ends of the fixed contact connection arm (31), the first positioning shaft (62) is arranged through the two baffle plates (52) and the pulling end (31 c), a limiting notch (521) is formed at one end of the baffle plate (52), and a limiting shaft (53) penetrating through the limiting notch (521) of each of the two baffle plates (52) is arranged through the fixed contact connection arm (31).

8. The system for locking and resetting the movable contact and the fixed contact of the molded case circuit breaker according to claim 1, wherein the fixed contact structure (200) further comprises a protection cover (4) and a protection cover rotating shaft (43), the protection cover (4) comprises a rotating arm (41) arranged on the outer side of the two baffles (52), a cover body (42) connected with the two rotating arms (41) and positioned on the upper side of the fixed contact (32), and an actuating rod (44) connected with the two rotating arms (41), the cover body (42) is provided with a yielding channel (45), the actuating rod (44) is provided with a third contact end (44 a), the fixed contact connecting arm (31) is provided with a fourth contact end (31 d) matched with the third contact end (44 a) to slide, the third contact end (44 a) and the fourth contact end (31 d) are inclined surfaces, the base (25) is provided with lugs (251) arranged corresponding to the rotating arms (41), and the protection cover rotating shaft (44) is provided with a third contact end (44 a) matched with the fourth contact end (31 d) to slide on the two lugs (41).

9. The resettable system after a movable contact and a static contact of a molded case circuit breaker are locked according to claim 6, wherein the connecting plate (1) is provided with a rotating shaft seat (11) matched with a rotating shaft of the connecting arm (31) of the fixed contact, two ends of the rotating shaft of the connecting arm (31) of the fixed contact are limited by the mounting plate (26), the rotating shaft seat (11) is provided with a yielding groove (12) for rotating a second rotating end (31 b) of the connecting arm (31) of the fixed contact, and one end, far away from the rotating shaft seat (11), of the connecting plate (1) is provided with a fixed contact bracket (7) positioned beside the fixed contact (32).

10. The resettable system after locking of a moving contact and a fixed contact of a molded case circuit breaker according to claim 1, wherein the fixed contact structure (200) further comprises a magnetic increasing sheet (8) arranged between the connecting plate (1) and the bracket.