CN217903054U - Plastic case circuit breaker - Google Patents

Abstract

The invention relates to a molded case circuit breaker, which belongs to the technical field of low-voltage distribution facilities and comprises a base, a protective shell, an upper cover, a transmission mechanism, a free body removing body, an insulating support, a contact piece, a flexible conductive piece and a rigid conductive piece. The contact piece is rotatably arranged in the inner cavity of the insulating support. The transmission mechanism is movably connected with the insulating support and is fixedly arranged in a movable space formed by mutually buckling the base and the upper cover. The protective shell is arranged between the transmission mechanism and the insulating support, is fixed in the movable space, and divides the movable space into an air inlet cavity, an opening and closing cavity, a dissociation removing cavity and a mechanical cavity. When the breaker is switched on, the air inlet cavity is communicated with the dissociation removing cavity through the switching cavity, a heat dissipation channel is formed inside the breaker, and low temperature rise operation of a product in a switching-on and electrifying state is realized; when the breaker is opened, the opening and closing cavity is closed, the air inlet cavity is cut off from the communication with the free cavity, free gas between the moving contact and the static contact in the opening state is guided to enter the free region, and damage to other regions in the breaker is avoided. The molded case circuit breaker provided by the invention has the advantages of low running temperature rise, reliable breaking performance and the like.

Description

Plastic case circuit breaker

Technical Field

The invention relates to a molded case circuit breaker, and belongs to the technical field of low-voltage distribution facilities.

Background

Circuit breakers are a core component of low voltage power distribution facilities. The circuit breaker is connected to a power distribution network in a certain line connection mode, so that fault protection of the electric line and the electric equipment is realized. The operation temperature rise and the fault current breaking capacity are closely related to the reliability and the safety of the use.

At present, the technical scheme of the molded case circuit breaker mostly adopts a natural convection heat dissipation mode, and due to the compact internal structure layout, an effective heat dissipation channel is difficult to form, and the operation temperature rise is high. In addition, the plastic case circuit breaker can generate free gas expanding outwards in the process of breaking fault current, and the current main technical scheme is that an arc extinguish chamber is made of ferromagnetic materials, so that the free gas is absorbed and dissipated, the free gas needs to be guided into the arc extinguish chamber, and the damage of the free gas to other facilities inside the plastic case circuit breaker, particularly a mechanical transmission system, is avoided. The main technical method at present is to take certain sealing measures to areas generating free gas in the process of breaking fault current of the circuit breaker, so as to reduce the diffusion of the free gas to areas except an arc extinguishing chamber in the circuit breaker. However, this closing measure simultaneously blocks the heat dissipation channel inside the circuit breaker, so that the operating temperature rise is worsened.

Disclosure of Invention

The invention aims to solve the problem of high operation temperature rise of the conventional molded case circuit breaker, and provides a technical scheme of a high-heat-dissipation circuit breaker so as to reduce the operation temperature rise of the molded case circuit breaker and improve the operation reliability of a system.

In order to solve the above problems, the present invention provides a molded case circuit breaker, which includes a base, a protection housing, an upper cover, a transmission mechanism, a free body, an insulating support, a contact, a flexible conductive member, and a rigid conductive member. The contact piece is rotatably arranged in the inner cavity of the insulating bracket. The transmission mechanism is movably connected with the insulating support and is fixedly arranged in a movable space formed by buckling the base and the upper cover. The transmission mechanism drives the insulating support to rotate in the movable space, and the insulating support drives the movable contact piece to rotate in the movable space to implement switching-on and switching-off of the circuit breaker. The protection shell is arranged between the transmission mechanism and the insulating support and fixed in the movable space. The protection shell divides the movable space into an air inlet cavity, an opening and closing cavity, a dissociation removing cavity and a mechanical cavity, and the air inlet cavity is communicated with the dissociation removing cavity through the opening and closing cavity. The insulating support is rotatably arranged in the opening and closing cavity. The contact pieces are connected and conducted with the rigid conductive pieces through the flexible conductive pieces.

Preferably, the insulating support is provided with an upper support body, the support body divides the inner cavity into a first channel, a second channel, a third channel and a fourth channel which are mutually communicated, the first channel is communicated with the air inlet cavity, and the third channel is communicated with the dissociation removing cavity. The contact piece is provided with an upper closing surface which can be attached to an upper limiting surface arranged on the upper supporting body, and the communication between the third channel and the deionization cavity is cut off. The contact piece is provided with a shielding surface which can be attached to a third channel surface arranged on the protective shell, and the communication between the third channel and the dissociation removing cavity is cut off. And a lower sealing surface is arranged on the insulating support, and is attached to the closed cambered surface arranged on the base, so that the communication between the fourth channel and the free cavity is cut off. A channel hole is formed in the flexible conductive piece, and the fourth channel is communicated with the first channel through the channel hole. Be equipped with the ventilation hole in the rigidity electrically conductive piece, admit air the chamber and communicate with first passageway through the ventilation hole.

Furthermore, the insulating support is provided with a hollow inner cavity. An upper supporting body is arranged above the inner cavity, an upper limiting surface is arranged on the inner side, facing the inner cavity, of the upper supporting body, and an upper sealing surface is arranged on the outer side, facing away from the inner cavity, of the upper supporting body. The lower support body is arranged below the inner cavity, the lower limit surface is arranged on the inner side, facing the inner cavity, of the lower support body, and the lower sealing surface is arranged on the outer side, facing away from the inner cavity, of the lower support body.

Furthermore, one side of the contact piece close to the upper supporting body is provided with an upper closing surface. One side of the contact piece close to the lower support body is provided with a lower closing surface. And a shielding surface is arranged on one side of the contact piece close to the third channel surface of the protective shell. The shielding surface is in natural transition connection with the upper closing surface.

Furthermore, one side of the protection shell, which is close to the insulating support, is provided with a first channel surface, and the first channel surface is in contour fit coupling with the upper closed surface of the insulating support. And a third channel surface is arranged on one side of the protection shell close to the contact piece, and the first channel surface is in contour fit coupling with the upper closed surface of the insulating support. The first channel surface and the third channel surface are naturally and transitionally connected through the concave second channel surface.

Furthermore, the flexible conductive piece comprises a connecting section, a flexible section and a fixing section. The fixed section naturally transits to the connecting section through the flexible section. And a channel hole is formed in the flexible section.

Furthermore, the rigid conductive piece comprises a fixed end, a transition section and a wiring end. The fixed end naturally transits to the wiring end through the transition section. And a vent hole is formed in the transition section.

Furthermore, an upper sealing surface is arranged on the support body, and the upper sealing surface can be attached to a first channel surface arranged on the protective shell to cut off the communication between the first channel and the second channel.

Compared with the prior art, the invention has the following beneficial effects:

the invention solves the problem that the operating temperature of the molded case circuit breaker is high, and the circuit breaker can naturally form a smooth heat dissipation air duct in a switching-on state, thereby forming good heat dissipation and low operating temperature rise; when the breaker is in an opening state, the heat dissipation air duct inside the breaker is closed, and free gas generated in the fault current breaking process can only enter the arc extinguish chamber to remove the free gas, so that reliable arc extinction is implemented. The invention has the advantages of low operation temperature rise, reliable breaking performance and the like.

Drawings

Fig. 1 is a three-dimensional schematic view of a molded case circuit breaker according to the present invention;

fig. 2 is a sectional view of a closed state of a molded case circuit breaker according to the present invention;

fig. 3 is a sectional view of an open state of a molded case circuit breaker according to the present invention;

fig. 4 is a sectional view of a closed state of a movable contact of a molded case circuit breaker according to the present invention;

fig. 5 is a sectional view showing an inverted state of a movable contact of a molded case circuit breaker according to the present invention;

fig. 6 is a three-dimensional schematic diagram of a conductive circuit of a molded case circuit breaker according to the present invention;

fig. 7 is a three-dimensional schematic diagram of several embodiments of a conductive circuit of a molded case circuit breaker according to the present invention;

fig. 8 is a three-dimensional schematic view of a protection case of a molded case circuit breaker according to the present invention;

fig. 9 is an exploded view of a structure of a molded case circuit breaker according to the present invention;

fig. 10 is a three-dimensional schematic view of an insulating holder of a molded case circuit breaker according to the present invention;

fig. 11 is a three-dimensional schematic view of a contact of a molded case circuit breaker according to the present invention.

Detailed Description

Features and exemplary embodiments of various aspects of the present application will be described in detail below, and in order to make objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are intended to be illustrative only and are not intended to be limiting. It will be apparent to one skilled in the art that the present application may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present application by illustrating examples thereof.

Description of the labeling:

base 10

Closed arc 105

Activity space 101

The housing 20 is protected by the gas inlet chamber 1011, the shutter chamber 1012, the deionization chamber 1013, and the mechanical chamber 1014

A first channel surface 201, a second channel surface 202, and a third channel surface 203

An upper cover 30, a transmission mechanism 40 and a free body removing body 50

Insulating support 60

Upper supporter 601

An upper closing surface 6011, an upper limiting surface 6012

Lower support 602

Lower sealing surface 6021 and lower limiting surface 6022

Inner cavity 603

First passage 6031, second passage 6032, third passage 6033, fourth passage 6034 contact 70, 70a, 70b

An upper closing surface 701, a lower closing surface 702, a shielding surface 703

Connection terminals 704, 704a, 704b

Connecting grooves 7041, 7041a, 7041b

Flexible conductive member 80, 80a, 80b

Connecting sections 801, 801a, 801b

Flexible segments 802, 802a, 802b

Fixed segments 803, 803a, 803b

Passage holes 804, 804a, 804b

Rigid conductive member 90

Fixed end 901, transition section 902, terminal 903 and ventilation hole 904

Stationary contact 11

In order to make the invention more comprehensible, preferred embodiments are described in detail below with reference to the accompanying drawings:

as shown in fig. 1 and 2, the molded case circuit breaker according to the present invention includes a base 10, a protection case 20, an upper cover 30, a transmission mechanism 40, a trip body 50, an insulating support 60, and a contact 70.

The contacts 70 are rotatably mounted in the cavity 603 of the dielectric holder 60. The contact piece 70 is a strip-shaped sheet made of a conductive material, and the circuit breaker completes contact conduction and separation isolation of the contact piece 70 and the stationary contact 11 through the rotation action of the contact piece 70, so that switching-on and switching-off of the circuit breaker are realized. The transmission mechanism 40 is movably connected with the insulating support 60, and the transmission mechanism 40 is fixedly arranged in a movable space 101 formed by buckling the base 10 and the upper cover 30. The transmission mechanism 40 drives the insulating support 60 to rotate in the moving space 101, and the insulating support 60 drives the contact sheet 70 to rotate in the moving space 101, so as to implement switching on and switching off of the circuit breaker. The protective housing 20 is disposed between the transmission mechanism 40 and the insulating bracket 60 and fixed in the movable space 101. The protective casing 20 divides the movable space 101 into an air inlet chamber 1011, an opening and closing chamber 1012, a deionization chamber 1013, and a mechanical chamber 1014. The air intake chamber 1011 is in air communication with the outside of the circuit breaker, and the air intake chamber 1011 may be in air communication with the deionization chamber 1013 via the open/close chamber 1012, and the deionization chamber 1013 is in air communication with the outside of the circuit breaker. The interior of the circuit breaker can form a heat dissipation channel which is communicated with the inside and the outside through the air inlet cavity 1011, the opening and closing cavity 1012 and the deionization cavity 1013.

A first channel surface 201 is arranged on one side of the protection shell 20 close to the insulating support 60, and a third channel surface 203 is arranged on one side of the protection shell 20 close to the contact 70. The first channel surface 201 and the third channel surface 203 are naturally transitionally connected by the concave second channel surface 202.

As shown in fig. 4, the insulating support 60 is provided with a hollow inner cavity 603. An upper supporting body 601 is arranged above the inner cavity 603, an upper limiting surface 6012 is arranged on the inner side of the upper supporting body 601 facing the inner cavity 603, an upper sealing surface 6011 is arranged on the outer side of the upper supporting body 601 opposite to the inner cavity 603, the upper sealing surface 6011 faces the protective shell 20, and the upper sealing surface 6011 and the first channel surface 201 in the inner contour of the protective shell 20 can be attached and coupled; a lower supporting body 602 is arranged below the inner cavity 603, a lower limiting surface 6022 is arranged on the inner side of the lower supporting body 602 facing the inner cavity 603, a lower sealing surface 6021 is arranged on the outer side of the lower supporting body 602 opposite to the inner cavity 603, and the lower sealing surface 6021 faces the base 10 and is matched with the inner contour of the base 10. The insulating support 60 is rotatably disposed in an open/close chamber 1012 surrounded by the inner contour of the protective housing 20 and the inner contour of the base 10.

An upper closing surface 701 is provided on the contact piece 70 on a side close to the upper support 601. The upper closing surface 701 is disposed at a position and in a shape corresponding to the upper limiting surface 6012 of the upper support 601 provided in the insulating holder 60, and the contact piece 70 is rotatable to a position where the upper closing surface 701 and the upper limiting surface 6012 are bonded. A lower closing surface 702 is provided on a side of the contact 70 adjacent to the lower support 602. The lower closing surface 702 is disposed at a position and shape corresponding to the lower limit surface 6022 on the lower support 602 provided with the insulating holder 60, and the contact piece 70 is rotatable to a position where the lower closing surface 702 is brought into contact with the lower limit surface 6022. A shielding surface 703 is disposed on one side of the contact 70 close to the third channel surface 203 of the protective housing 20, and the third channel surface 203 is coupled to the shielding surface 703 of the contact 70 in a contour fitting manner. The shielding surface 703 is naturally transitionally connected with the upper closing surface 701.

The insulating holder 60, together with the contact 70, divides the cavity 603 into a first passage 6031, a second passage 6032, a third passage 6033, and a fourth passage 6034 that communicate with each other. When the circuit breaker is closed, the first passage 6031 communicates with the intake chamber 1011 and the third passage 6033 communicates with the deionization chamber 1013. The air inlet cavity 1011 is communicated with the deionization cavity 1013 through a first channel 6031, a second channel 6032 and a third channel 6033 in sequence, and a heat dissipation channel is formed inside the circuit breaker.

As shown in fig. 3, when the circuit breaker is opened, the blocking surface 703 provided on the contact 70 is attached to the third channel surface 203 provided on the protection housing 20, so as to cut off the communication between the third channel 6033 and the deionization chamber 1013. The lower sealing surface 6021 arranged on the insulating bracket 60 is jointed with the sealing cambered surface 105 arranged on the base 10 to cut off the communication between the fourth channel 6034 and the deionization chamber 1013. The support 601 is provided with an upper sealing surface 6011, and the upper sealing surface 6011 may be attached to the first channel surface 201 provided on the protective housing 20 to cut off the communication between the first channel 6031 and the second channel 6032. Thus, the contact 70 and the dielectric support 60 completely close the open/close chamber 1012, thereby closing the chamber 1013. If the brake-off process generates the free gas in the deionization chamber 1013, the free gas can only flow in the deionization chamber 1013, so that the free gas can only enter the deionization chamber 1013 to perform absorption quenching, and does not enter other internal regions to damage the internal structure of the circuit breaker.

As shown in fig. 5, when the contact 70 rotates until the shielding surface 703 provided on the contact 70 is engaged with the third passage surface 203 provided on the protective housing 20, the communication between the third passage 6033 and the deionization chamber 1013 is cut off. At this time, the lower seal surface 6021 provided on the insulating support 60 is fitted to the seal curved surface 105 provided on the base 10, and the communication between the fourth passage 6034 and the deionization chamber 1013 is cut off. Thus, the contact 70 and the dielectric support 60 completely close the open/close chamber 1012, thereby closing the chamber 1013. If the brake-off process generates the free gas in the deionization chamber 1013, the free gas can only flow in the deionization chamber 1013, so that the free gas can only enter the deionization chamber 1013 to perform absorption quenching, and does not enter other internal regions to damage the internal structure of the circuit breaker.

As shown in fig. 6, the contact 70 is electrically connected to a rigid conductive member 90 via a flexible conductive member 80. The flexible conductive member 80 includes a connecting section 801, a flexible section 802, and a fixing section 803. The fixed section 803 naturally transitions to the connecting section 801 via the flexible section 802. The flexible section 802 has a passage hole 804 therein. The fourth passage 6034 communicates with the first passage 6031 via the passage hole 804. When the circuit breaker is switched on and generates heat, heat generated by the contact can be communicated with the first channel 6031 from the fourth channel 6034 through the channel hole 804, and heat dissipation is implemented. The rigid conductive member 90 includes a fixed end 901, a transition section 902, and a terminal 903. The fixed end 901 naturally transitions to the terminal 903 through a transition section 902. A vent 904 is provided in the transition section 902. The intake chamber 1011 communicates with the first passage 6031 via the vent 904. When the circuit breaker closes the circular telegram and generates heat, the outside cold air of circuit breaker can follow air intake chamber 1011 and communicate with first passageway 6031 through ventilation hole 904, implements ventilation cooling to the heat conductor that generates heat internally.

As shown in fig. 7, an alternative embodiment of the conductive circuit of the circuit breaker is shown. Fig. 7 shows the 1 st embodiment on the right, the 2 nd embodiment in the middle and the 3 rd embodiment on the left. The contact 70 of embodiment 1 is provided with a connecting end 704 for connecting and conducting with the flexible conductive member 80, the connecting end 704 is provided with a connecting groove 7041 for fixing the connecting section 801 on the upper closing surface 701, and the passage hole 804 is a through hole provided on the flexible section 802.

The connection grooves 7041a of embodiment 2 are disposed on two sides of the connection end 704a, the flexible segment 802a of the flexible conductive component 80a is divided into two pieces that are bifurcated in the middle, the fixed connection segment 801a is disposed at the end portions of the two flexible segments 802a, the two fixed connection segments 801a are fixedly connected and conducted with the connection groove 7041a, and a channel hole 804a is naturally formed in the middle of the flexible segment 802a by matching with the two flexible segments 802 a.

The connection groove 7041b of embodiment 3 is disposed on one side of the connection end 704b, the flexible segment 802b of the flexible conductive device 80b is disposed on one side, the fixed connection segment 801b is disposed at an end of the flexible segment 802b, the fixed connection segment 801b is fixedly connected and conducted with the connection groove 7041b, and a channel hole 804b is naturally formed on a hollowed side of the flexible segment 802 b.

While the invention has been described with respect to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Those skilled in the art can make various changes, modifications and equivalents to the disclosed technology without departing from the spirit and scope of the present invention, and all such changes, modifications and equivalents are intended to be included therein as equivalents of the present invention; meanwhile, any changes, modifications and variations of the above-described embodiments, which are equivalent to those of the technical spirit of the present invention, are within the scope of the technical solution of the present invention.

Claims (10)

1. A molded case circuit breaker comprises a base (10), a protective shell (20), an upper cover (30), a transmission mechanism (40), a free body (50), an insulating support (60), a contact piece (70), a flexible conductive piece (80) and a rigid conductive piece (90);

the insulating support (60) is provided with a hollow inner cavity (603);

the contact piece (70) is rotatably arranged in an inner cavity (603) of the insulating bracket (60);

the transmission mechanism (40) is movably connected with the insulating support (60), and the transmission mechanism (40) is fixedly arranged in a movable space (101) formed by buckling the base (10) and the upper cover (30);

the transmission mechanism (40) drives the insulating support (60) to rotate in the movable space (101), and the insulating support (60) drives the contact (70) to rotate in the movable space (101) to implement switching on and switching off of the circuit breaker;

the method is characterized in that:

the protective shell (20) is arranged between the transmission mechanism (40) and the insulating support (60) and is fixed in the movable space (101); the protective shell (20) divides the movable space (101) into an air inlet cavity (1011), an opening and closing cavity (1012), a deionization cavity (1013) and a mechanical cavity (1014), wherein the air inlet cavity (1011) is communicated with the deionization cavity (1013) through the opening and closing cavity (1012); the insulating bracket (60) is rotatably arranged in the open-close cavity (1012).

2. A molded case circuit breaker according to claim 1, characterized in that:

be equipped with support body (601) on insulating support (60), support body (601) is gone up and is separated inner chamber (603) for first passageway (6031), second passageway (6032), third passageway (6033), fourth passageway (6034) that communicate each other, first passageway (6031) and admit air chamber (1011) intercommunication, third passageway (6033) and remove free chamber (1013) intercommunication.

3. A molded case circuit breaker according to claim 2, characterized in that:

the contact piece (70) is provided with an upper closing surface (701), the upper closing surface (701) can be attached to the upper support body (601) to cut off the communication between the opening and closing cavity (1012) and the deionization cavity (1013);

the insulating bracket (60) is provided with a lower sealing surface (6021), the lower sealing surface (6021) is hermetically attached to the base (10), and the communication between the opening and closing cavity (1012) and the deionization cavity (1013) is cut off.

4. A molded case circuit breaker according to claim 3, characterized in that:

the upper closing surface (701) of the contact piece (70) can be attached to an upper limiting surface (6012) arranged on the upper supporting body (601) to cut off the communication between a third channel (6033) and the deionization chamber (1013);

a shielding surface (703) is arranged on the contact piece (70), the shielding surface (703) can be attached to a third channel surface (203) arranged on the protective shell (20) to cut off the communication between a third channel (6033) and the deionization cavity (1013);

and a lower sealing surface (6021) is arranged on the insulating bracket (60), the lower sealing surface (6021) is attached to a sealing arc surface (105) arranged on the base (10), and the communication between a fourth channel (6034) and the dissociation removing cavity (1013) is cut off.

5. A molded case circuit breaker according to claim 4, wherein:

the upper supporting body (601) is positioned above the inner cavity (603), an upper limiting surface (6012) is arranged on the inner side, facing the inner cavity (603), of the upper supporting body (601), and an upper sealing surface (6011) is arranged on the outer side, back to the inner cavity (603), of the upper supporting body (601);

a lower support body (602) is arranged below the inner cavity (603), a lower limiting surface (6022) is arranged on the inner side of the lower support body (602) facing the inner cavity (603), and a lower sealing surface (6021) is arranged on the outer side of the lower support body (602) back to the inner cavity (603).

6. A molded case circuit breaker, as recited in claim 5, wherein: a first channel surface (201) is arranged on one side, close to the insulating support (60), of the protective shell (20), and the first channel surface (201) is in contour fit coupling with an upper closed surface (6011) of the insulating support (60);

a third channel surface (203) is arranged on one side, close to the contact (70), of the protective shell (20), and the third channel surface (203) is in contour fit coupling with a shielding surface (703) of the contact (70);

the first channel surface (201) and the third channel surface (203) are naturally transitionally connected through the concave second channel surface (202).

7. A molded case circuit breaker according to claim 6, wherein: an upper closing surface (701) is arranged on one side, close to the upper supporting body (601), of the contact piece (70);

a lower closing surface (702) is arranged on one side of the contact piece (70) close to the lower support body (602);

a shielding surface (703) is arranged on one side of the contact piece (70) close to the third channel surface (203) of the protective shell (20);

the shielding surface (703) is in natural transition connection with the upper closing surface (701).

8. A molded case circuit breaker, as recited in claim 7, wherein:

an upper sealing surface (6011) is arranged on the support body (601), and the upper sealing surface (6011) can be attached to a first channel surface (201) arranged on the protective shell (20) to cut off the communication between the first channel (6031) and the second channel (6032).

9. A molded case circuit breaker, as recited in claim 2, wherein:

the contact piece (70) is connected and conducted with the rigid conductive piece (90) through the flexible conductive piece (80);

a channel hole (804) is formed in the flexible conductive piece (80), and the fourth channel (6034) is communicated with the first channel (6031) through the channel hole (804);

a ventilation hole (904) is formed in the rigid conductive piece (90), and the air inlet cavity (1011) is communicated with the first channel (6031) through the ventilation hole (904).

10. A molded case circuit breaker, as recited in claim 9, wherein:

the flexible conducting piece (80) comprises a connecting section (801), a flexible section (802) and a fixed section (803),

the fixed section (803), via the flexible section (802), naturally transitions into the connecting section (801),

a channel hole (804) is formed in the flexible section (802);

the rigid conductive piece (90) comprises a fixed end (901), a transition section (902) and a terminal (903), wherein the fixed end (901) naturally transitions to the terminal (903) through the transition section (902), and a ventilation hole (904) is formed in the transition section (902).

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