CN221176120U - A molded case circuit breaker - Google Patents

Abstract

The utility model relates to the technical field of piezoelectric devices, in particular to a molded case circuit breaker. The molded case circuit breaker comprises a circuit breaker shell, and a main arc extinguishing system, a main contact system, an operating mechanism and a tripping system which are arranged in the circuit breaker shell, wherein the main contact system comprises a main fixed contact, a main contact and a main contact rotating shaft, and the operating mechanism drives the main contact to rotate through the main contact rotating shaft so as to enable the main contact to be contacted with or separated from the main fixed contact; the main arc extinguishing system and the main contact system are positioned at the upper part of the breaker shell and distributed from left to right along the length direction of the breaker shell; the tripping system is positioned below the main contact rotating shaft and at least partially coincides with the projection of the main contact rotating shaft in the height direction of the breaker shell; the lower extreme of circuit breaker casing just is provided with power end and load end along the length direction of circuit breaker casing from left to right. The whole length of moulded case circuit breaker is shorter, can satisfy the installation demand in narrow and small space, improves the space utilization of cubical switchboard.

Description

Plastic case circuit breaker

Technical Field

The utility model relates to the technical field of piezoelectric devices, in particular to a molded case circuit breaker.

Background

The internal structure of the conventional molded case circuit breaker is shown in fig. 1, and comprises a power supply end, an arc extinguishing system, a contact system, a tripping system and a load end, wherein the structure is distributed from left to right along the length direction. Along with the development of the market, the molded case circuit breaker needs to be miniaturized to meet the installation requirement of compact space, and the molded case circuit breaker with the structure has long whole length and does not meet the installation requirement of compact space.

Disclosure of utility model

The utility model aims to provide a molded case circuit breaker with compact structure and high space utilization rate.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

The molded case circuit breaker comprises a circuit breaker shell, and a main arc extinguishing system, a main contact system, an operating mechanism and a tripping system which are arranged in the circuit breaker shell, wherein the main contact system comprises a main fixed contact, a main contact and a main contact rotating shaft, the main contact is connected with the main contact rotating shaft, and the operating mechanism drives the main contact to rotate through the main contact rotating shaft so as to enable the main contact to be contacted with or separated from the main fixed contact; the main arc extinguishing system and the main contact system are positioned at the upper part of the breaker shell and distributed from left to right along the length direction of the breaker shell; the tripping system is positioned below the main contact rotating shaft and at least partially coincides with the projection of the main contact rotating shaft in the height direction of the breaker shell; the lower extreme of circuit breaker casing just follows the length direction of circuit breaker casing is provided with power end and load end from left to right.

Further, the circuit breaker further comprises a current limiting system arranged in the circuit breaker shell, wherein the current limiting system comprises an auxiliary contact structure, an auxiliary arc extinguishing chamber and an elastic piece;

The auxiliary contact structure comprises an auxiliary fixed contact, an auxiliary moving contact and an auxiliary contact rotating shaft, wherein one end of the auxiliary fixed contact is connected with the power end, and one end of the auxiliary moving contact is connected with the main fixed contact; the auxiliary moving contact can rotate around the auxiliary contact rotating shaft so as to be contacted with or separated from the auxiliary fixed contact; the elastic piece is used for driving the auxiliary moving contact to rotate around the auxiliary contact rotating shaft along the direction of approaching the auxiliary fixed contact;

The current limiting system is positioned below the main arc extinguishing system and at least partially coincides with the projection of the main arc extinguishing system in the height direction of the breaker shell;

the current limiting system and the tripping system are distributed from left to right along the length direction of the breaker housing.

Further, the length direction of the auxiliary fixed contact is parallel to the height direction of the breaker shell or forms an acute angle smaller than 45 degrees with the height direction of the breaker shell.

Further, the device also comprises a main static contact conducting rod, wherein a first inserting groove is formed in the main static contact conducting rod; the main fixed contact is provided with a second inserting groove;

The current limiting system further comprises an overcurrent protection shell and two plugboards, and the auxiliary contact structure and the auxiliary arc extinguishing chamber are arranged in the overcurrent protection shell; one ends of the two plug boards extend into the overcurrent protection shell and are respectively connected with the auxiliary fixed contact and the auxiliary moving contact, and the other ends of the two plug boards extend out of the overcurrent protection shell and are respectively inserted into the first plug groove and the second plug groove.

Further, the left end face of the breaker shell along the length direction is concavely provided with a mounting groove, and the overcurrent protection shell is arranged in the mounting groove.

Further, the left end face of the overcurrent protection shell along the length direction of the circuit breaker shell is flush with the left end face of the circuit breaker shell along the length direction;

The openings of the first inserting groove and the second inserting groove face the left end face of the breaker shell.

Further, the breaker further comprises a striking rod rotatably connected in the breaker shell, and the rotation center of the striking rod is positioned between the operating mechanism and the tripping system; the operating mechanism comprises a traction rod, the upper part of the striking rod corresponds to the traction rod, the lower part of the striking rod corresponds to the tripping system, and the rotation center of the striking rod is positioned between the upper part and the lower part of the striking rod;

The striking rod is positioned at one side of the tripping system away from the main fixed contact.

Further, the device also comprises a driving contact conducting rod, wherein the lower end of the driving contact conducting rod is connected with the load end;

The tripping system comprises a bimetallic strip, one end of the bimetallic strip is fixed on the surface of the driving contact conducting rod, which is far away from the main fixed contact, and the other end of the bimetallic strip corresponds to the lower part of the striking rod.

Further, the device also comprises a driving contact conducting rod, wherein the lower end of the driving contact conducting rod is connected with the load end;

The tripping system comprises a magnetic yoke and an armature, wherein the magnetic yoke surrounds the active contact conducting rod and is opened at the surface of the active contact conducting rod away from the main fixed contact; the armature is positioned at one side of the active contact conducting rod, which is far away from the main fixed contact, and corresponds to the opening of the magnetic yoke; the armature is rotatably connected in the breaker shell, and two sides of the armature, which are positioned at the rotation center of the armature, respectively correspond to the magnetic yoke and the striking rod.

Further, the device also comprises a driving contact conducting rod, wherein the lower end of the driving contact conducting rod is connected with the load end;

The tripping system comprises a transformer and a magnetic flux converter, the transformer is sleeved on the driving contact conducting rod, and the magnetic flux converter is positioned on one side, far away from the main static contact, of the driving contact conducting rod and corresponds to the lower part of the striking rod.

The utility model has the beneficial effects that:

The utility model provides a molded case circuit breaker which comprises a circuit breaker shell, a main arc extinguishing system, a main contact system, an operating mechanism and a tripping system, wherein the main arc extinguishing system, the main contact system, the operating mechanism and the tripping system are arranged in the circuit breaker shell; the main arc extinguishing system and the main contact system are positioned at the upper part of the breaker shell and distributed from left to right along the length direction of the breaker shell; the tripping system is positioned below the main contact rotating shaft and at least partially coincides with the projection of the main contact rotating shaft in the height direction of the breaker shell; the lower extreme of circuit breaker casing just is provided with power end and load end along the length direction of circuit breaker casing from left to right.

In the molded case circuit breaker, at least part of the structure of the tripping system, which is originally positioned at one side of the main contact rotating shaft, moves to the position right below the main contact rotating shaft, and the power end and the load end are both arranged at the lower end of the circuit breaker; the whole length of the circuit breaker can be greatly shortened through the structural layout, so that the circuit breaker can meet the installation requirement of a narrow space, and the space utilization rate of the switch cabinet is improved.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present utility model, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural view of a molded case circuit breaker according to the prior art;

Fig. 2 is a schematic structural diagram of a molded case circuit breaker according to a first embodiment of the present utility model when a current is turned on;

Fig. 3 is a schematic structural diagram of a molded case circuit breaker according to a first embodiment of the present utility model when a short circuit occurs;

Fig. 4 is a schematic diagram of a plastic case circuit breaker according to the first embodiment;

fig. 5 is a schematic view of an internal structure of a molded case circuit breaker according to a first embodiment of the present utility model when a current is turned on;

fig. 6 is a schematic view of an internal structure of a molded case circuit breaker according to a first embodiment of the present utility model when a current is disconnected;

Fig. 7 is a schematic structural diagram of a thermal trip assembly in a molded case circuit breaker according to the first embodiment;

Fig. 8 is a schematic structural diagram of a magnetic trip assembly in a molded case circuit breaker according to the first embodiment;

fig. 9 is a schematic structural diagram of an electronic trip unit in a molded case circuit breaker according to a second embodiment;

Fig. 10 is a schematic diagram of an internal structure of a molded case circuit breaker according to a third embodiment of the present utility model.

Icon:

1-a breaker housing; 11-mounting slots;

2-a main arc extinguishing system;

3-a main contact system; 31-a main fixed contact; 32-active contacts; 33-main contact rotating shaft;

4-an operating mechanism; 41-a traction rod; 42-handle;

A 5-trip system; 51-a bimetal; 52-a magnetic yoke; 53-armature; 54-mutual inductor; 55-flux transformer;

61-a power supply terminal; 62-load side;

7-a current limiting system; 71-auxiliary contact structure; 711-auxiliary fixed contacts; 712-auxiliary moving contact; 713-auxiliary contact shaft; 72-auxiliary arc extinguishing chamber; 73-an elastic member; 74-an overcurrent protection housing; 75-plugboard;

81-a main static contact conducting rod; 811-a first socket; 82-active contact conducting rod;

9-striking rod.

Detailed Description

The technical solutions of the present utility model will be clearly and completely described in connection with the embodiments, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, in the description of the present utility model, the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

It should be noted that, in the description of the present utility model, the terms "connected" and "mounted" should be understood in a broad sense, and for example, may be a fixed connection, a detachable connection, or an integral connection; can be directly connected or connected through an intermediate medium; either mechanically or electrically. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Example 1

The embodiment provides a molded case circuit breaker, referring to fig. 2, the molded case circuit breaker comprises a circuit breaker housing 1, and a main arc extinguishing system 2, a main contact system 3, an operating mechanism 4 and a tripping system 5 which are arranged in the circuit breaker housing 1, wherein the main contact system 3 comprises a main fixed contact 31, a main contact 32 and a main contact rotating shaft 33, the main contact 32 is connected to the main contact rotating shaft 33, and the operating mechanism 4 drives the main contact 32 to rotate through the main contact rotating shaft 33 so as to enable the main contact 32 to be contacted with or separated from the main fixed contact 31; the main arc extinguishing system 2 and the main contact system 3 are positioned at the upper part of the breaker housing 1 and distributed from left to right along the length direction of the breaker housing 1; the tripping system 5 is located below the main contact rotating shaft 33 and at least partially coincides with the projection of the main contact rotating shaft 33 in the height direction of the breaker housing 1; the lower end of the breaker housing 1 is provided with a power source terminal 61 and a load terminal 62 from left to right along the length direction of the breaker housing 1.

In the molded case circuit breaker, at least part of the structure of the tripping system 5, which is originally located on one side of the main contact rotating shaft 33 far away from the main fixed contact 31 along the length direction of the circuit breaker, moves to the position right below the main contact rotating shaft 33, and the power supply end 61 and the load end 62 are both arranged at the lower end of the circuit breaker; the whole length of the circuit breaker can be greatly shortened through the structural layout, so that the circuit breaker can meet the installation requirement of a narrow space, and the space utilization rate of the switch cabinet is improved.

Further, the molded case circuit breaker further comprises a current limiting system 7 arranged in the circuit breaker housing 1, wherein the current limiting system 7 comprises an auxiliary contact structure 71, an auxiliary arc extinguishing chamber 72 and an elastic piece 73; wherein:

The auxiliary contact structure 71 comprises an auxiliary fixed contact 711, an auxiliary moving contact 712 and an auxiliary contact rotating shaft 713, wherein one end of the auxiliary fixed contact 711 is connected to the power supply end 61, and one end of the auxiliary moving contact 712 is connected to the main fixed contact 31; the auxiliary moving contact 712 is rotatable about the auxiliary contact rotating shaft 713 to be in contact with or separated from the auxiliary stationary contact 711;

the auxiliary arc extinguishing chamber 72 is located at one side of the auxiliary moving contact 712 away from the auxiliary contact rotating shaft 713, and is used for extinguishing an arc generated when the auxiliary fixed contact 711 and the auxiliary moving contact 712 are disconnected;

The elastic member 73 is used to drive the auxiliary moving contact 712 to rotate around the auxiliary contact rotating shaft 713 in a direction approaching the auxiliary fixed contact 711.

Alternatively, the elastic member 73 may be a tension spring, and both ends of the tension spring are connected to the auxiliary fixed contact 711 and the auxiliary moving contact 712, respectively, so that the auxiliary moving contact 712 has a tendency to rotate toward the auxiliary fixed contact 711.

In this embodiment, the operating mechanism 4 includes a handle 42, and the handle 42 is pushed leftwards along the length direction, so that the operating mechanism 4 drives the main contact rotating shaft 33 to rotate anticlockwise, and the main contact 32 is connected with the main fixed contact 31. The auxiliary contact structure 71 is connected in series between the main stationary contact 31 and the power supply terminal 61, specifically, the auxiliary stationary contact 711 and the auxiliary moving contact 712 are connected in series between the main stationary contact 31 and the power supply terminal 61.

Referring to fig. 2 and 5, at normal current, the main stationary contact 31 and the active contact 32 are in contact, and the elastic member 73 makes the auxiliary moving contact 712 contact with the auxiliary stationary contact 711, thereby turning on the current; at this time, the current flows from the power source terminal 61, the auxiliary fixed contact 711, the auxiliary moving contact 712, the main fixed contact 31, the active contact 32, and the load terminal 62.

Referring to fig. 3, when a short circuit current occurs, the auxiliary moving contact 712 is repelled from the auxiliary fixed contact 711 by a large electric repulsive force, an arc occurs between the auxiliary moving contact 712 and the auxiliary fixed contact 711, and the short circuit current is limited by a rapidly increased arc resistance, thereby performing a current limiting function. The arc between the auxiliary moving contact 712 and the auxiliary fixed contact 711 enters the auxiliary arc-extinguishing chamber 72, is cut and extinguished by the metal grid sheet of the auxiliary arc-extinguishing chamber 72, and completes the breaking of the auxiliary contact structure 71.

Referring to fig. 4 and 6, since the actuation time of the trip system 5 is slower than the repulsion time of the auxiliary fixed contact 711 and the auxiliary moving contact 712, after the auxiliary moving contact 712 is repelled, the trip system 5 actuates to trip the operating mechanism 4, the operating mechanism 4 drives the main contact rotating shaft 33 to rotate clockwise to disconnect the main fixed contact 31 and the main contact 32, and the arc between the main fixed contact 31 and the main contact 32 enters the main arc extinguishing system 2 and is cut and extinguished by the metal grid sheet of the main arc extinguishing system 2. After the main contact system 3 is disconnected, the elastic piece 73 enables the auxiliary moving contact 712 and the auxiliary fixed contact 711 to be in a connected state for being used when being disconnected again.

In the above structure, the auxiliary contact structure 71 is connected in series between the main stationary contact 31 and the power supply terminal 61, so that the short-circuit current is limited, the current value of the actual breaking of the main contact system 3 and the main arc extinguishing system 2 is reduced, and the breaking capacity of the molded case circuit breaker is improved.

Referring to fig. 5, the length direction of the auxiliary stationary contact 711 is parallel to the height direction of the breaker case 1 or forms an acute angle of less than 45 ° with the height direction of the breaker case 1.

Further, the main fixed contact 31 includes a first portion and a second portion, one end of the first portion can contact with or separate from the active contact 32, the other end of the first portion is connected to one end of the second portion, and one end of the second portion, which is far from the first portion, is connected to the auxiliary moving contact 712; wherein the first part is parallel to the length direction of the breaker housing 1 or forms an acute angle smaller than 45 degrees with the length direction of the breaker housing 1, and the second part is parallel to the height direction of the breaker housing 1 or forms an acute angle smaller than 45 degrees with the height direction of the breaker housing 1.

The arrangement can fully utilize the space of the breaker housing 1 in the height direction, so that the length of the auxiliary fixed contact 711 can be conveniently increased; in addition, compared with the arrangement that the length direction of the auxiliary fixed contact 711 is parallel to the height direction of the breaker housing 1, the arrangement that the angle is formed between the two can further increase the length of the auxiliary fixed contact 711. The layout can fully utilize the internal space of the breaker housing 1 to meet the market demand of miniaturization of the breaker.

Optionally, the main stationary contact 31 further includes a third portion, and two ends of the third portion are connected to the second portion and the auxiliary moving contact 712, respectively.

In the above-described configuration, the current flow in the auxiliary fixed contact 711 is from bottom to top, and the current flow in the auxiliary moving contact 712 is from top to bottom, and the current flowing through the auxiliary moving contact 712 is opposite to the current flowing through the auxiliary fixed contact 711, so that an electric repulsive force exists between the two, and the auxiliary moving contact 712 is not in contact with the auxiliary fixed contact 711 again under a large electric repulsive force before the main contact system 3 is disconnected. In an alternative embodiment, a limiting structure is arranged on one side of the auxiliary moving contact 712 away from the auxiliary fixed contact 711, and the auxiliary moving contact 712 is abutted against the limiting structure after being repelled; illustratively, the limiting structure may be a plate or a protrusion. The length of the opposite conductors of the auxiliary moving contact 712 and the auxiliary fixed contact 711 and the distance between the auxiliary moving contact 712 and the auxiliary fixed contact 711 are reasonably set, so that the auxiliary moving contact 712 receives repulsive force between the auxiliary moving contact 712 and the auxiliary fixed contact 711 after the auxiliary moving contact 712 is separated and before the main contact system 3 is disconnected, and the auxiliary moving contact 712 is kept in abutting connection with the limiting device.

Optionally, the lower end of the auxiliary fixed contact 711 is connected to the power supply end 61, or the lower end of the auxiliary fixed contact 711 is the power supply end 61.

As an alternative embodiment, in the embodiment that the auxiliary fixed contact 711 is located in the circuit breaker housing 1, the lower end of the auxiliary fixed contact 711 extends to the outer shape of the circuit breaker housing 1 through a conductive structure to form a power supply end 61, and is connected with a power supply; the lower end of the auxiliary static contact 711, namely the power supply end 61, can also be connected with a power supply through a conductive structure; for the embodiment in which the lower end of the auxiliary stationary contact 711 extends out of the breaker housing 1, the lower end of the auxiliary stationary contact 711 is the power supply end 61.

In the present embodiment, the auxiliary arc extinguishing chamber 72 and the auxiliary contact structure 71 are distributed from top to bottom in the height direction of the breaker housing 1.

Further, the current limiting system 7 is located below the main arc extinguishing system 2 and at least partially coincides with the projection of the main arc extinguishing system 2 in the height direction of the breaker housing 1;

The current limiting system 7 and the tripping system 5 are distributed from left to right along the length of the circuit breaker housing 1.

In the structure, the current limiting system 7 and the tripping system 5 can fully utilize the space in the middle and/or lower part of the molded case circuit breaker in the height direction, so that the whole length of the circuit breaker is not increased on the basis of setting the current limiting system 7, and the circuit breaker has the advantages of high breaking capacity and small occupied space.

On the basis of the above structure, the tripping system 5 is a thermo-magnetic tripping device, i.e. the tripping system 5 comprises a thermal tripping assembly for overload protection of the circuit breaker and a magnetic tripping assembly for short-circuit protection of the circuit breaker.

Referring to fig. 5 and 7, the molded case circuit breaker further includes a striking rod 9 rotatably connected to the inside of the circuit breaker case 1, the rotation center of the striking rod 9 being located between the operating mechanism 4 and the trip system 5; the operating mechanism 4 comprises a traction rod 41, the upper part of the striking rod 9 corresponds to the traction rod 41, the lower part of the striking rod 9 corresponds to the tripping system 5, and the rotation center of the striking rod 9 is positioned between the upper part and the lower part of the striking rod 9;

the striking rod 9 is located on the side of the trip system 5 remote from the main stationary contact 31.

Specifically, the molded case circuit breaker further includes a driving contact conductive rod 82, wherein the lower end of the driving contact conductive rod 82 is connected to the load end 62 (or the lower end of the driving contact conductive rod 82 is the load end 62);

The trip system 5 includes a bimetal 51, one end of the bimetal 51 is fixed to a surface of the driving contact conductive rod 82, which is far away from the main fixed contact 31, and the other end of the bimetal 51 corresponds to a lower portion of the striking rod 9.

As an alternative embodiment, in the embodiment that the active contact conductive rod 82 is located in the circuit breaker housing 1, the lower end of the active contact conductive rod 82 extends to the outside of the circuit breaker housing 1 through a conductive structure to form a load end 62, and is connected with a load; the lower end of the active contact conducting rod 82, namely the power supply end 61, can also be connected with a power supply through a conducting structure; for the embodiment in which the lower end of the active contact conductive rod 82 passes out of the breaker housing 1, the lower end of the active contact conductive rod 82 is the load end 62, and is connected to a load.

Referring to fig. 7, when an overload current flows, the upper end of the bimetal 51 is heated to be bent in a direction away from the main stationary contact 31, pushing the lower portion of the striking rod 9, and rotating the striking rod 9 counterclockwise; the upper portion of the striking rod 9 pushes the traction rod 41 to trip the operating mechanism 4.

Referring to fig. 8, the trip system 5 includes a yoke 52 and an armature 53, the yoke 52 surrounding the active contact conductive rod 82 and opening at a surface of the active contact conductive rod 82 remote from the main stationary contact 31; the armature 53 is positioned on one side of the active contact conducting rod 82 away from the main fixed contact 31 and corresponds to the opening of the magnetic yoke 52; the armature 53 is rotatably connected to the inside of the breaker case 1, and both sides of the armature 53 at the rotation center thereof correspond to the yoke 52 and the striking rod 9, respectively.

When short-circuited, the yoke 52 attracts the armature 53, causing the armature 53 to rotate clockwise, the upper portion of the armature 53 pushes the lower portion of the striking rod 9, causing the striking rod 9 to rotate counterclockwise, and the upper portion of the striking rod 9 pushes the traction rod 41, causing the operating mechanism 4 to trip.

The above embodiment links the operating mechanism 4 and the tripping system 5 through the striking rod 9, so that the tripping system 5 (including the bimetallic strip 51, the magnetic yoke 52 and the armature 53) can be completely arranged below the main contact rotating shaft 33, and the striking rod 9 is arranged at one side of the main contact rotating shaft 33 far away from the main fixed contact 31, thereby achieving the purpose of reducing the whole length of the circuit breaker and meeting the market demand of miniaturization of the circuit breaker.

Example two

The embodiment provides a molded case circuit breaker, referring to fig. 9, the molded case circuit breaker further includes a driving contact conductive rod 82, and a lower end of the driving contact conductive rod 82 is connected to the load end 62;

The tripping system 5 comprises a mutual inductor 54 and a magnetic flux converter 55, wherein the mutual inductor 54 is sleeved on the driving contact conducting rod 82, and the magnetic flux converter 55 is positioned on one side of the driving contact conducting rod 82 away from the main static contact 31 and corresponds to the lower part of the striking rod 9.

In this embodiment, the trip system 5 is an electronic trip unit. When overload or short circuit occurs, the magnetic flux transformer 55 pushes the lower portion of the striking rod 9, so that the striking rod 9 rotates counterclockwise, and the upper portion of the striking rod 9 pushes the traction rod 41, so that the operating mechanism 4 is tripped.

In the above-described embodiment, the trip system 5 (including the transformer 54 and the flux transformer 55) can be disposed entirely below the main contact rotating shaft 33.

Example III

The embodiment provides a molded case circuit breaker, referring to fig. 10, the molded case circuit breaker further includes a main fixed contact conductive rod 81, two ends of the main fixed contact conductive rod 81 are respectively connected to a power supply end 61 and an auxiliary fixed contact 711; the main fixed contact conducting rod 81 is provided with a first plug-in groove 811; the main fixed contact 31 is provided with a second inserting groove; the openings of the first plug-in groove 811 and the second plug-in groove are both directed toward the left end face of the circuit breaker housing 1.

The current limiting system 7 further comprises an overcurrent protection housing 74 and two plug boards 75, and the auxiliary contact structure 71 and the auxiliary arc extinguishing chamber 72 are arranged in the overcurrent protection housing 74; one ends of the two plug boards 75 extend into the overcurrent protection housing 74 and are respectively connected to the auxiliary fixed contact 711 and the auxiliary movable contact 712, and the other ends of the two plug boards 75 extend out of the overcurrent protection housing 74 and are respectively inserted into the first plug groove 811 and the second plug groove.

Alternatively, one of the plug plates 75 and the auxiliary stationary contact 711 may be integrally formed.

As an alternative embodiment, in the embodiment that the main static contact conductive rod 81 is located in the circuit breaker housing 1, the lower end of the main static contact conductive rod 81 extends to the outside of the circuit breaker housing 1 through a conductive structure to form a power supply end 61, and is connected with a power supply; the lower end of the main static contact conducting rod 81 is a power supply end 61 and is connected with a power supply through a conducting structure; in the embodiment in which the lower end of the main static contact conductive rod 81 passes through the breaker housing 1, the lower end of the main static contact conductive rod 81 is the power end 61 and is connected to a power source.

In addition to the above configuration, the left end face of the breaker case 1 in the longitudinal direction is recessed with the mounting groove 11, and the overcurrent protection case 74 is provided in the mounting groove 11.

In one embodiment, the mounting slot 11 extends through the left side end face of the circuit breaker housing 1. In another embodiment, the mounting slot 11 has a slot floor at the left end face remote from the circuit breaker housing 1, and two tabs 75 extend through the slot floor of the mounting slot 11.

Preferably, the left end face of the overcurrent protection case 74 in the length direction of the breaker case 1 is flush with the left end face of the breaker case 1 in the length direction.

When the current limiting system 7 is installed, the current limiting system 7 is pushed into the installation groove 11 from left to right along the length direction of the breaker housing 1; the two plug boards 75 are automatically aligned with the first plug slot 811 and the second plug slot to connect the current limiting system 7 in series in the power circuit. When the current limiting system 7 needs to be replaced, the current limiting system 7 can be conveniently replaced by pulling out the current limiting system 7 from the mounting groove 11.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Claims (10)

1. The utility model provides a moulded case circuit breaker, includes circuit breaker casing (1) and set up main arc extinguishing system (2), main contact system (3), operating device (4) and tripping system (5) in circuit breaker casing (1), main contact system (3) are including main stationary contact (31), initiative contact (32) and main contact pivot (33), initiative contact (32) are connected in main contact pivot (33), operating device (4) are through main contact pivot (33) drive initiative contact (32) rotate, so that initiative contact (32) with main stationary contact (31) contact or separate; the circuit breaker is characterized in that the main arc extinguishing system (2) and the main contact system (3) are positioned at the upper part of the circuit breaker shell (1) and distributed from left to right along the length direction of the circuit breaker shell (1); the tripping system (5) is positioned below the main contact rotating shaft (33) and at least partially coincides with the projection of the main contact rotating shaft (33) in the height direction of the breaker shell (1); the circuit breaker is characterized in that a power supply end (61) and a load end (62) are arranged at the lower end of the circuit breaker shell (1) from left to right along the length direction of the circuit breaker shell (1).

2. The molded case circuit breaker according to claim 1, further comprising a current limiting system (7) disposed within the circuit breaker housing (1), the current limiting system (7) comprising an auxiliary contact structure (71), an auxiliary arc chute (72) and an elastic member (73);

The auxiliary contact structure (71) comprises an auxiliary fixed contact (711), an auxiliary moving contact (712) and an auxiliary contact rotating shaft (713), one end of the auxiliary fixed contact (711) is connected to the power supply end (61), and one end of the auxiliary moving contact (712) is connected to the main fixed contact (31); the auxiliary moving contact (712) can rotate around the auxiliary contact rotating shaft (713) to be contacted with or separated from the auxiliary fixed contact (711); the elastic piece (73) is used for driving the auxiliary moving contact (712) to rotate around the auxiliary contact rotating shaft (713) along the direction approaching the auxiliary fixed contact (711);

the current limiting system (7) is positioned below the main arc extinguishing system (2) and at least partially coincides with the projection of the main arc extinguishing system (2) in the height direction of the breaker housing (1);

The current limiting system (7) and the tripping system (5) are distributed from left to right along the length direction of the breaker housing (1).

3. The molded case circuit breaker according to claim 2, wherein the length direction of the auxiliary stationary contact (711) is parallel to the height direction of the circuit breaker housing (1) or forms an acute angle smaller than 45 ° with the height direction of the circuit breaker housing (1).

4. The molded case circuit breaker according to claim 2, further comprising a main stationary contact conductive rod (81), wherein a first plugging groove (811) is provided on the main stationary contact conductive rod (81); the main fixed contact (31) is provided with a second inserting groove;

The current limiting system (7) further comprises an overcurrent protection shell (74) and two plugboards (75), wherein the auxiliary contact structure (71) and the auxiliary arc extinguishing chamber (72) are arranged in the overcurrent protection shell (74); one ends of the two plug boards (75) extend into the overcurrent protection shell (74) and are respectively connected with the auxiliary fixed contact (711) and the auxiliary moving contact (712), and the other ends of the two plug boards (75) extend out of the overcurrent protection shell (74) and are respectively inserted into the first plug groove (811) and the second plug groove.

5. The molded case circuit breaker according to claim 4, wherein the left end face of the circuit breaker housing (1) along the length direction is concavely provided with a mounting groove (11), and the overcurrent protection housing (74) is disposed in the mounting groove (11).

6. The molded case circuit breaker according to claim 5, wherein a left end face of the overcurrent protection case (74) in a length direction of the circuit breaker case (1) is flush with a left end face of the circuit breaker case (1) in the length direction;

The openings of the first plug-in groove (811) and the second plug-in groove face the left end face of the breaker housing (1).

7. A molded case circuit breaker according to any one of claims 1 to 6, further comprising a striking rod (9) rotatably connected inside the circuit breaker housing (1), the center of rotation of the striking rod (9) being located between the operating mechanism (4) and the trip system (5); the operating mechanism (4) comprises a traction rod (41), the upper part of the striking rod (9) corresponds to the traction rod (41), the lower part of the striking rod (9) corresponds to the tripping system (5), and the rotation center of the striking rod (9) is positioned between the upper part and the lower part of the striking rod (9);

The striking rod (9) is positioned on one side of the tripping system (5) away from the main fixed contact (31).

8. The molded case circuit breaker according to claim 7, further comprising a driving contact conductive rod (82), a lower end of the driving contact conductive rod (82) being connected to the load end (62);

The tripping system (5) comprises a bimetallic strip (51), one end of the bimetallic strip (51) is fixed on the surface of the driving contact conducting rod (82) far away from the main fixed contact (31), and the other end of the bimetallic strip (51) corresponds to the lower part of the striking rod (9).

9. The molded case circuit breaker according to claim 7, further comprising a driving contact conductive rod (82), a lower end of the driving contact conductive rod (82) being connected to the load end (62);

The tripping system (5) comprises a magnetic yoke (52) and an armature (53), wherein the magnetic yoke (52) surrounds the active contact conducting rod (82) and is opened at the surface of the active contact conducting rod (82) far away from the main fixed contact (31); the armature (53) is positioned on one side of the active contact conducting rod (82) away from the main fixed contact (31) and corresponds to the opening of the magnetic yoke (52); the armature (53) is rotatably connected in the breaker shell (1), and two sides of the armature (53) positioned at the rotation center of the armature are respectively corresponding to the magnet yoke (52) and the striking rod (9).

10. The molded case circuit breaker according to claim 7, further comprising a driving contact conductive rod (82), a lower end of the driving contact conductive rod (82) being connected to the load end (62);

The tripping system (5) comprises a mutual inductor (54) and a magnetic flux converter (55), wherein the mutual inductor (54) is sleeved on the driving contact conducting rod (82), and the magnetic flux converter (55) is located at one side, far away from the main static contact (31), of the driving contact conducting rod (82) and corresponds to the lower part of the striking rod (9).