Molded case circuit breaker

Abstract

The invention relates to a molded case circuit breaker, which comprises a shell, and an arc extinguishing mechanism, an operating mechanism, a contact assembly and a tripping unit which are arranged in the shell, the contact assembly comprises a moving contact and a static contact, the arc extinguishing mechanism comprises a fixing frame and a plurality of first arc extinguishing grid sheets which are obliquely arranged, the fixing frame is fixedly arranged in the shell, and the first arc extinguishing grid sheets are fixedly arranged in the shell. The fixed frame is provided with an installation space and a containing cavity located below the installation space, the first arc extinguishing grid pieces are located in the installation space, a notch is formed in the middle of each first arc extinguishing grid piece, a through groove communicated with the installation space is formed in the bottom of the fixed frame, the static contact is arranged in the containing cavity, and the end of the static contact extends into the notch. And the moving contact is movably arranged in the notch and is in contact with or separated from the static contact. By adopting the technical scheme, the molded case circuit breaker provided by the invention has the advantages that the internal structure of a switch cabinet body is prevented from being damaged by electric arcs generated in the circuit breaker, and meanwhile, dust and explosive media in the surrounding environment can be effectively filtered.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breakers, and in particular to a molded case circuit breaker. Background Art

[0002] Molded case circuit breaker (MCCB) is a commonly used low-voltage circuit breaker, which can connect, carry and disconnect current under normal circuit conditions, and can also connect, carry a certain time and segment current under specified abnormal circuit conditions (overload, short circuit, especially short circuit). It can usually be used in conjunction with leakage circuit, measurement and electric operation module units, and needs to be installed in the switch cabinet. Therefore, the molded case circuit breaker has higher requirements for the air at the installation site.

[0003] The current molded case circuit breaker is roughly composed of a shell, a contact system, an operating system, an arc extinguishing system, a release, etc. Among them, when the moving contact and the static contact of the contact system are out of contact and a gap is generated in the energized state, if the current cannot be disconnected in time, the contacts will be burned due to long-term arcing, affecting the power supply and service life of the circuit breaker. In addition, the existing use scenarios of circuit breakers are mostly in industrial and urban low-voltage factories. The dust pollutants and explosive media generated in the production environment of most factories and the conductive dust in the air are easy to accumulate at the wiring of the circuit breaker, and most circuit breakers are exposed to conductive After the interference of dust, false tripping is very likely to occur, resulting in frequent tripping of the circuit carried by the circuit breaker; in addition, when the circuit breaker breaks a large short-circuit current, an arc will be generated between the static contact piece and the moving contact rod inside the circuit breaker. Although the generated arc will be sucked into the arc extinguishing chamber through the arc extinguishing electrode and cooled, before the arc is completely extinguished, a part of the circuit or ionized gas will be ejected from the arc spray port at the power supply end of the circuit breaker and hit the structure of the switch cabinet where the circuit breaker is located, causing damage to the switch cabinet structure. Therefore, the design of the arc extinguishing system has an important influence on the performance of the molded case circuit breaker. Summary of the invention

[0004] Purpose of the invention: In order to overcome the defects of the prior art, the present invention provides a molded case circuit breaker to reduce the arc generated in the circuit breaker from damaging the internal structure of the switch cabinet, and at the same time can effectively filter out dust and explosive media in the surrounding environment.

[0005] The technical solution of the present invention is as follows: a molded case circuit breaker comprises a shell and an arc extinguishing mechanism, an operating mechanism, a contact assembly and a tripping unit arranged in the shell, the contact assembly comprises a moving contact and a static contact, the operating mechanism comprises a handle and a rotating shaft that moves synchronously with the handle, the moving contact is arranged on the rotating shaft and rotates synchronously with the rotation, the swing of the handle can drive the moving contact to contact or separate from the static contact to achieve closing or opening, the arc extinguishing mechanism comprises a fixing frame and a plurality of first arc extinguishing grids arranged obliquely, both sides of each first arc extinguishing grid are integrally or fixedly provided with fixing plates, the fixing frame is fixedly arranged in the shell, an installation space and a accommodating cavity located below the installation space are provided on the fixing frame, the first arc extinguishing grid is located in the installation space, a notch is provided in the middle of each first arc extinguishing grid, and a notch is provided at the bottom of the fixing frame that is in contact with the installation The movable contact is movably arranged in the slot to contact or separate from the static contact. The arc extinguishing mechanism also includes a second arc extinguishing grid and an insulating sheet. The second arc extinguishing grid is arranged between the first arc extinguishing grid and the insulating sheet, and the second arc extinguishing grid is located at the upper end of the fixing frame. The second arc extinguishing grid is provided with an extension sheet extending in the direction of the first arc extinguishing grid. The second arc extinguishing grid and the extension sheet are provided with a plurality of exhaust holes. The upper end surface of the shell is provided with a mounting groove and an opening located at the periphery of the mounting groove at the position corresponding to the arc extinguishing mechanism. A metal dustproof net and a filter plate are provided in the mounting groove. The metal dustproof net is located above the filter plate. A locking piece for fixing the metal dustproof net and the filter plate in the mounting groove is provided on the inner side wall of the shell at the periphery of the mounting groove.

[0006] By adopting the above technical scheme, multiple first arc-extinguishing grids cut the arc, weaken it layer by layer, and are inclined so that the arc moves upward and is led to the second arc-extinguishing grid. The internal gas of the circuit breaker is discharged from the exhaust hole, changing the direction of the gas and suppressing the secondary short circuit phenomenon caused by direct arc injection. A metal dust screen and a filter plate are arranged on the upper end surface of the shell, so that the electric gas generated in the circuit breaker can adhere to the filter plate made of metal material, so that the filter plate has a strong charge and transfers the charge to the metal dust screen on the front side of the front cover, so as to adsorb the conductive dust with weak charge, reduce the conductive dust entering the circuit breaker, and adsorb the dust and explosive medium at the same time, so as to reduce the interference of the external environment on the normal operation of the circuit breaker.

[0007] A further configuration of the present invention: the shell includes a base and an upper cover which are arranged in a split manner, the fixing frame is arranged in the base, and the base is provided with a first terminal area, a contact arc extinguishing area, a transformer installation area and a second terminal area in sequence along its length direction, a plurality of first partitions are provided in the first terminal area and the contact arc extinguishing area along the width direction of the base, a plurality of second partitions are provided in the second terminal area, each first partition and the inner side wall of the base are provided with a first positioning groove, the fixing frame and the two sides of the insulating sheet are inserted in the first positioning groove, the upper cover is correspondingly provided with a second positioning groove, and the two sides of the second arc extinguishing grid sheet are inserted in the second positioning groove.

[0008] With the above further arrangement, the split arrangement facilitates the installation of various components inside the shell. The insulating plate and the second arc extinguishing grid are arranged in the first terminal area and are located above the wiring terminal, which can effectively save space. At the same time, it can also lengthen the arc extinguishing length, increase the cooling area, and reduce the temperature of the arc. The plug-in installation facilitates the installation and makes the structure of each component stable.

[0009] The present invention is further configured as follows: the locking member comprises a fixed rod and a pressing block rotatably arranged on the fixed rod, a pressing spring is sleeved on the fixed rod, and the pressing spring abuts against the pressing block.

[0010] By adopting the above-mentioned further arrangement, the metal dust screen and the filter plate are easy to disassemble. By rotating the pressing block, it can be taken out of the installation groove for replacement. At the same time, after installation, the pressing block is used to press it to make its structure stable in the installation groove, and the pressing spring presses the pressing block to make the filter plate and the metal dust screen fit better, thereby better realizing the adsorption of conductive dust with weaker charge and reducing the conductive dust entering the circuit breaker.

[0011] The present invention is further configured as follows: a mounting plate arranged in a "7" shape is provided on the base, a first mounting groove arranged horizontally and a second mounting groove arranged vertically are provided on the mounting plate, a first circuit board and a second circuit board are provided in the first mounting groove, the first circuit board is located above the second circuit board, the second mounting groove is located above the transformer installation area, a wireless communication module and a connector conductively connected to the wireless communication module are provided in the second mounting groove, and an opening corresponding to the position of the wireless communication module is provided on the upper cover.

[0012] By adopting the above-mentioned further arrangement, the redundant internal space on the base can be fully utilized, and each component can be reasonably arranged and installed on the circuit breaker, which has a small change on the overall volume of the circuit breaker, and a good isolation effect can be produced between these components, thereby improving the stability of the circuit breaker during operation. The wireless communication module can be connected to the second circuit board through the connector, and the plug-in cooperation facilitates the disassembly and assembly of the wireless communication module.

[0013] The present invention is further configured as follows: the connector is detachably disposed in the second mounting groove, the connector includes a base body and a third circuit board disposed on the base body, a first connector is disposed on the third circuit board, a second connector is disposed on the second circuit board, and the second connector is plugged into and matched with the first connector.

[0014] By adopting the above-mentioned further arrangement, disassembly and assembly are convenient and quick, and subsequent maintenance and replacement are convenient.

[0015] The present invention is further provided with: the third circuit board is also provided with a third connector which is plugged and matched with the wireless communication module.

[0016] By further configuring the above configuration, multiple types of third connectors can be configured to facilitate the connection of wireless communication modules of different models, thereby being able to adapt at least two wireless communication modules of different standards to the same circuit breaker product, thereby improving the applicability of the product and reducing the cost of use.

[0017] The present invention is further configured as follows: the tripping unit comprises an electromagnetic tripper and a sliding member capable of driving the circuit breaker to open; the electromagnetic tripper is arranged on a mounting plate; a traction rod is provided in the arc extinguishing area of ​​the contacts; a bracket is fixedly provided on the mounting plate; a reset spring is provided between the sliding member and the bracket; a driving block is provided on the sliding member; when the output end of the electromagnetic tripper is retracted and the sliding member slides forward under the action of the reset spring, the driving block presses the traction rod to drive the traction rod to rotate, thereby realizing the tripping and opening of the circuit breaker.

[0018] By adopting the above-mentioned further configuration, the circuit breaker has overload, undervoltage and leakage protection functions. When the current is too large, the principle of magnetic return force is used to generate a magnetic field force in the circuit, so that the output end of the electromagnetic release is retracted. When the output end of the electromagnetic release is retracted, the reset spring pushes the sliding part to slide forward, and pushes the traction rod to rotate, so that the circuit breaker is opened, thereby realizing the protection function.

[0019] The present invention is further configured as follows: a mounting frame is provided in the transformer installation area, the mounting frame is provided with at least three mounting slots, each mounting slot is provided with a current transformer, the output end of each phase current transformer is electrically connected to the first circuit board, and a guide groove is provided on the side wall of each mounting slot along its vertical direction for the iron core of each current transformer to slide into when the current transformer is installed.

[0020] By adopting the above-mentioned further configuration, the installation of each current transformer can be more convenient and stable, and the installation slots are separated to prevent the current transformers of each phase from interfering with each other during use, so that the circuit breaker can be used more stably and accurately.

[0021] The present invention is further configured as follows: the electromagnetic release includes a coil and a locking piece, wherein the coil is fixedly arranged on a bracket, the locking piece is hingedly arranged on the bracket through a torsion spring, the locking piece has a resistance arm and a locking arm, wherein the resistance arm is arranged corresponding to the moving iron core of the coil, a locking port is arranged on the sliding piece, the sliding piece slides so that the locking port on the sliding piece is locked by the locking arm, and the moving iron core of the coil works and moves to push the resistance arm to release the locking arm.

[0022] By adopting the above-mentioned further arrangement, the electromagnetic release has a reasonable structure, stable operation and no erroneous operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of a specific embodiment of the present invention; Figure 2 It is an internal schematic diagram of a specific embodiment of the present invention; Figure 3 It is a schematic diagram of an arc extinguishing mechanism according to a specific embodiment of the present invention; Figure 4 It is a top view of the arc extinguishing mechanism of a specific embodiment of the present invention; Figure 5 is a schematic diagram of a fixing frame according to a specific embodiment of the present invention; Figure 6 It is a schematic diagram of a top cover of a specific embodiment of the present invention; Figure 7 It is a schematic diagram of a metal dust screen and a filter plate according to a specific embodiment of the present invention; Figure 8 It is a schematic diagram of an operating mechanism and an arc extinguishing mechanism according to a specific embodiment of the present invention; Fig. 9 is a schematic diagram of a trip unit according to a specific embodiment of the present invention; Fig.10 is a schematic diagram of a locking member according to a specific embodiment of the present invention; Fig.11 It is a schematic diagram of a mounting plate and a connector according to a specific embodiment of the present invention; Fig.12 is a schematic diagram of a wireless communication module according to a specific embodiment of the present invention; Fig.13 It is a member pass during the installation of the current transformer in a specific embodiment of the present invention; Fig.14 is a schematic diagram of a base according to a specific embodiment of the present invention; Fig.15 It is a schematic diagram of a mounting frame and a current transformer according to a specific embodiment of the present invention; Fig.16 It is a schematic diagram of a traction rod according to a specific embodiment of the present invention; Fig.17 It is a schematic diagram of a sliding member and a locking member according to a specific embodiment of the present invention.

[0024] In the figure, 1, housing; 11, mounting groove; 111, metal dust screen; 112, filter plate; 12, locking piece; 121, fixing rod; 122, pressing block; 123, pressing spring; 13, upper cover; 131, second positioning groove; 14, base; 141, first terminal area; 142, contact arc extinguishing area; 143, transformer mounting area; 144, second terminal area; 15, first partition; 151, positioning groove; 16, second partition; 2, arc extinguishing mechanism; 21, fixing frame; 211, mounting space; 212, accommodating cavity; 22, first arc extinguishing grid; 221, notch; 23, fixing plate; 24, second arc extinguishing grid; 241, extension piece; 25, insulator Edge piece; 26, exhaust hole; 3, operating mechanism; 31, handle; 32, rotating shaft; 4, contact assembly; 41, moving contact; 42, static contact; 5, trip unit; 51, electromagnetic release; 511, coil; 512, locking member; 5121, resistance arm; 5122, locking arm; 52, sliding member; 521, driving block; 522, locking port; 6, mounting plate; 61, first mounting slot; 62, second mounting slot; 63, first circuit board; 64, second circuit board; 65, wireless communication module; 66, plug-in connector; 661, seat; 662, third circuit board; 7, traction rod; 8, bracket; 9, reset spring; 10, mounting bracket; 101, current transformer. DETAILED DESCRIPTION

[0025] The technical scheme in this embodiment will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that in the description of the present invention, all directional indications (such as up, down, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0027] In addition, in the present invention, the descriptions such as "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. In the description of the present invention, the meaning of "several" is at least two, such as two, three, etc., unless otherwise clearly and specifically limited.

[0028] In addition, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by those skilled in the art. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0029] like Figure 1-17As shown, a molded case circuit breaker includes a housing 1 and an arc extinguishing mechanism 2, an operating mechanism 3, a contact assembly 4 and a trip unit 5 arranged in the housing 1, wherein the contact assembly 4 includes a moving contact 41 and a stationary contact 42, the operating mechanism 3 includes a handle 31 and a rotating shaft 32 that moves synchronously with the handle 31, the moving contact 41 is arranged on the rotating shaft 32 and rotates synchronously with the rotation, the swing of the handle 31 can drive the moving contact 41 to contact or separate from the stationary contact 42 to achieve closing or opening, the arc extinguishing mechanism 2 includes a fixing frame 21 and a plurality of inclined first arc extinguishing grids 22, both sides of each first arc extinguishing grid 22 are integrally or fixedly provided with a fixing plate 23, the modular arrangement is more convenient when it is installed in the fixing frame 21, and can also ensure The structures between the first arc-extinguishing grids 22 are stable, the fixing frame 21 is fixedly arranged in the housing 1, and the fixing frame 21 is provided with an installation space 211 and a receiving cavity 212 located below the installation space 211, the first arc-extinguishing grid 22 is located in the installation space 211, and a notch 221 is provided in the middle position of each first arc-extinguishing grid 22, and a through groove communicating with the installation space 211 is opened at the bottom of the fixing frame 21, the static contact 42 is arranged in the receiving cavity 212, and the end portion extends into the notch 221, the moving contact 41 is movably arranged in the notch 221 to contact or separate from the static contact 42, and the arc-extinguishing mechanism 2 also includes a second arc-extinguishing grid 24 and an insulating sheet 25, and the second arc-extinguishing grid 24 is arranged on the first arc-extinguishing grid 22 and the insulating sheet 25, and the second arc-extinguishing grid 24 is located at the upper end of the fixing frame 21, and the second arc-extinguishing grid 24 is provided with an extension sheet 241 extending in the direction of the first arc-extinguishing grid 22, and a plurality of exhaust holes 26 are opened on the second arc-extinguishing grid 24 and the extension sheet 241, and the upper end surface of the shell 1 is provided with a mounting groove 11 and an opening located at the periphery of the mounting groove 11 at a position corresponding to the arc-extinguishing mechanism 2, and a metal dust-proof net 111 and a filter plate 112 are provided in the mounting groove 11, and the metal dust-proof net 111 is located above the filter plate 112, and a locking piece 12 for fixing the metal dust-proof net 111 and the filter plate 112 in the mounting groove 11 is provided on the inner side wall of the shell 1 at the periphery of the mounting groove 11, and a plurality of first arc-extinguishing grids 22 are provided to lock the electric The arc is cut and weakened layer by layer, and is tilted so that the arc moves upward and is led to the second arc extinguishing grid 24. The gas inside the circuit breaker is discharged from the exhaust hole 26, which changes the direction of the gas and suppresses the secondary short circuit phenomenon caused by the direct injection of the arc. A metal dustproof net 111 and a filter plate 112 are arranged on the upper end surface of the shell 1, so that the electric gas generated in the circuit breaker can be attached to the filter plate 112 made of metal material, so that the filter plate 112 has a strong charge and transfers the charge to the metal dustproof net 111 on the front side of the front cover, so as to adsorb the conductive dust with weak charge, reduce the conductive dust entering the circuit breaker, and adsorb the dust and explosive medium at the same time, so as to reduce the interference of the external environment on the normal operation of the circuit breaker.

[0030] The housing 1 includes a base 14 and an upper cover 13 which are arranged in a split manner. The fixing frame 21 is arranged in the base 14. The base 14 is provided with a first terminal area 141, a contact arc extinguishing area 142, a transformer installation area 143 and a second terminal area 144 in sequence along its length direction. A plurality of first partitions 15 are arranged in the first terminal area 141 and the contact arc extinguishing area 142 along the width direction of the base 14. A plurality of second partitions 16 are arranged in the second terminal area 144. A first positioning groove 151 is arranged on each first partition 15 and the inner side wall of the base 14. The fixing frame 21 is provided with a first positioning groove 151 on each first partition 15 and the inner side wall of the base 14. 1 and both sides of the insulating sheet 25 are inserted into the first positioning groove 151, and the upper cover 13 is correspondingly provided with a second positioning groove 131151, and both sides of the second arc-extinguishing grid 24 are inserted into the second positioning groove 131151. The split arrangement is convenient for the installation of various components inside the housing 1. The insulating plate and the second arc-extinguishing grid 24 are arranged in the first terminal area 141 and are located above the wiring terminal, which can effectively save space, and at the same time can also lengthen the arc extinguishing length, increase the cooling area, and reduce the temperature of the arc. The plug-in installation is convenient for each installation and makes the structure of each component stable.

[0031] The locking member 12 includes a fixing rod 121 and a pressing block 122 rotatably arranged on the fixing rod 121. A pressing spring 123 is sleeved on the fixing rod 121, and the pressing spring 123 abuts against the pressing block 122. The metal dust screen 111 and the filter plate 112 are easy to disassemble. The pressing block 122 can be taken out of the mounting groove 11 for replacement by rotating it. After installation, the pressing block 122 is pressed to stabilize its structure in the mounting groove 11, and the pressing spring 123 presses the pressing block 122, so that the filter plate 112 and the metal dust screen 111 are more closely fitted, so as to better realize the adsorption of conductive dust with weaker charge and reduce the conductive dust entering the circuit breaker. Alternatively, a cover plate may be hingedly provided on the inner top wall of the shell 1, and the filter plate 112 and the metal dust screen 111 may be pressed into the mounting groove 11 by pressing the cover plate against the four sides of the filter plate 112, and the other end of the cover plate may be fixed by a snap connection or other means.

[0032] The base 14 is provided with a mounting plate 6 arranged in a "7" shape, and the mounting plate 6 is provided with a first mounting groove 6111 arranged horizontally and a second mounting groove 6211 arranged vertically. The first mounting groove 6111 is provided with a first circuit board 63 and a second circuit board 64, and the first circuit board 63 is located above the second circuit board 64. The second mounting groove 6211 is located above the transformer installation area 143. The second mounting groove 6211 is provided with a wireless communication module 65 and a connector 66 conductively connected to the wireless communication module 65. The upper cover 13 is open at the position corresponding to the wireless communication module 65, so that the redundant internal space on the base 14 can be fully utilized. All of them can be reasonably arranged and installed on the circuit breaker, which has little effect on the overall volume of the circuit breaker, and these components can produce a good isolation effect, which improves the stability of the circuit breaker during operation. The wireless communication module 65 can be connected to the second circuit board 64 through the plug-in connector 66, and the plug-in fit facilitates the disassembly and assembly of the wireless communication module 65. The plug-in connector 66 is detachably arranged in the second installation groove 6211. The plug-in connector 66 includes a seat body 661 and a third circuit board 662 arranged on the seat body 661. The third circuit board 662 is provided with a first connector, and the second circuit board 64 is provided with a second connector. The second connector is plugged and matched with the first connector, which is convenient and quick to disassemble and assemble, and is convenient for subsequent maintenance and replacement. The third circuit board 662 is also provided with a third connector plugged and matched with the wireless communication module 65. The third connector can be provided in multiple ways to facilitate the connection of wireless communication modules 65 of different models, so that at least two wireless communication modules 65 of different standards can be adapted to the same circuit breaker product, thereby improving the applicability of the product and reducing the use cost.

[0033] The trip unit 5 includes an electromagnetic release 51 and a sliding member 52 that can drive the circuit breaker to open. The electromagnetic release 51 is arranged on the mounting plate 6, a traction rod 7 is arranged in the contact arc extinguishing area 142, a bracket 8 is fixedly arranged on the mounting plate 6, a reset spring 9 is arranged between the sliding member 52 and the bracket 8, and a driving block 521 is arranged on the sliding member 52. When the output end of the electromagnetic release 51 is retracted, the sliding member 52 slides forward under the action of the reset spring 9, and the driving block 521 presses the traction rod 7 to drive the traction rod 7 to rotate, so that the circuit breaker is tripped and opened, so that the circuit breaker has overload, undervoltage and leakage protection functions. When the current is too large, the principle of magnetic back force is used to generate a magnetic field force in the circuit, so that the output end of the electromagnetic release 51 is retracted. When the output end of the electromagnetic release 51 is retracted, the reset spring 9 pushes the sliding member 52 to slide forward, and pushes the traction rod 7 to rotate to realize the circuit breaker opening, thereby realizing the protection function. The electromagnetic release 51 includes a coil 511 and a locking member 512, wherein the coil 511 is fixedly arranged on the bracket 8, and the locking member 12 is hingedly arranged on the bracket 8 through a torsion spring. The locking member 512 has a resistance arm 5121 and a locking arm 5122, wherein the resistance arm 5121 is arranged corresponding to the moving iron core of the coil 511, and a locking port 522 is arranged on the sliding member 52. The sliding member 52 slides so that the locking port 522 on the sliding member 52 is locked by the locking arm 5122. The working moving iron core of the coil 511 moves to push the resistance arm 5121 to release the locking arm 5122, so that the structure of the electromagnetic release 51 is reasonable, the operation is stable, and there will be no misoperation.

[0034] A mounting frame 10 is provided in the transformer installation area 143, and at least three mounting slots 11 are provided on the mounting frame 10. A current transformer 101 is provided in each mounting slot 11. The output end of each phase current transformer 101 is electrically connected to the first circuit board 63. A guide slot is provided on the side wall of each mounting slot 11 along its vertical direction, which is used for the iron core of each current transformer 101 to slide into when each current transformer 101 is installed, so that the installation of each current transformer 101 can be more convenient and stable, and the separation of each mounting slot 11 can prevent the current transformers 101 of each phase from interfering with each other during use, so that the circuit breaker can be used more stably and accurately.

Claims

1. A molded case circuit breaker, comprising a housing (1) and an arc extinguishing mechanism (2), an operating mechanism (3), a contact assembly (4) and a trip unit (5) arranged in the housing (1), wherein the contact assembly (4) comprises a moving contact (41) and a stationary contact (42), the operating mechanism (3) comprises a handle (31) and a rotating shaft (32) that moves synchronously with the handle (31), the moving contact (41) being arranged on the rotating shaft (32) and rotating synchronously with the rotating shaft (32), the swinging of the handle (31) can drive the moving contact (41) to contact or separate from the stationary contact (42) to achieve closing or opening, characterized in that: The arc extinguishing mechanism (2) comprises a fixing frame (21) and a plurality of first arc extinguishing grids (22) arranged obliquely, a fixing plate (23) being integrally or fixedly provided on both sides of each first arc extinguishing grid (22), the fixing frame (21) being fixedly provided in the housing (1), a mounting space (211) and a receiving cavity (212) located below the mounting space (211) being provided on the fixing frame (21), the first arc extinguishing grids (22) being located in the mounting space (211), a notch (221) being provided at the middle position of each first arc extinguishing grid (22), a through slot communicating with the mounting space (211) being provided at the bottom of the fixing frame (21), the static contact (42) being provided in the receiving cavity (212), and an end portion extending into the notch (221), the movable contact (41) being movably provided in the notch (221) to contact or separate from the static contact (42), the arc extinguishing mechanism (2) further comprising a second arc extinguishing grid (24) and The insulating sheet (25), the second arc-extinguishing grid (24) is arranged between the first arc-extinguishing grid (22) and the insulating sheet (25), and the second arc-extinguishing grid (24) is located at the upper end of the fixing frame (21), the second arc-extinguishing grid (24) is provided with an extension sheet (241) extending in the direction of the first arc-extinguishing grid (22), the second arc-extinguishing grid (24) and the extension sheet (241) are provided with a plurality of exhaust holes (26), and the upper end surface of the housing (1) corresponds to An installation groove (11) and an opening located at the periphery of the installation groove (11) are provided at the position of the arc extinguishing mechanism (2); a metal dust screen (111) and a filter plate (112) are provided in the installation groove (11); the metal dust screen (111) is located above the filter plate (112); and a locking piece (12) is provided on the inner side wall of the housing (1) located at the periphery of the installation groove (11) for fixing the metal dust screen (111) and the filter plate (112) in the installation groove (11).

2. The molded case circuit breaker according to claim 1, characterized in that: The housing (1) comprises a base (13) and an upper cover (14) which are arranged in a split manner. The fixing frame (21) is arranged in the base (13). The base (13) is provided with a first terminal area (141), a contact arc extinguishing area (142), a transformer installation area (143) and a second terminal area (144) in sequence along its length direction. The first terminal area (141) and the contact arc extinguishing area (142) are provided with a plurality of first partitions (143) along the width direction of the base (13). 5), a plurality of second partitions (16) are provided in the second terminal area (144), a first positioning groove (151) is provided on the inner side wall of each first partition (15) and the base (13), the fixing frame (21) and the two sides of the insulating sheet (25) are inserted into the first positioning groove (151), the upper cover (14) is correspondingly provided with a second positioning groove (131) (151), and the two sides of the second arc-extinguishing grid sheet (24) are inserted into the second positioning groove (131) (151).

3. The molded case circuit breaker according to claim 1 or 2, characterized in that: The locking member (12) comprises a fixing rod (121) and a pressing block (122) rotatably arranged on the fixing rod (121); a pressing spring (123) is sleeved on the fixing rod (121), and the pressing spring (123) abuts against the pressing block (122).

4. The molded case circuit breaker according to claim 2, characterized in that: The base (13) is provided with a mounting plate (6) arranged in a "7" shape, and the mounting plate (6) is provided with a first mounting groove (61) (11) arranged horizontally and a second mounting groove (62) (11) arranged vertically, and a first circuit board (63) and a second circuit board (64) are arranged in the first mounting groove (61) (11), and the first circuit board (63) is located above the second circuit board (64), and the second mounting groove (62) (11) is located above the transformer installation area (143), and a wireless communication module (65) and a connector (66) that is electrically conductively connected to the wireless communication module (65) are arranged in the second mounting groove (62) (11), and the upper cover (14) is provided with an opening corresponding to the position of the wireless communication module (65).

5. The molded case circuit breaker according to claim 4, characterized in that: The plug connector (66) is detachably disposed in the second mounting groove (62) (11), and comprises a base (661) and a third circuit board (662) disposed on the base (661); a first connector is disposed on the third circuit board (662), and a second connector is disposed on the second circuit board (64); the second connector is plugged into and matched with the first connector.

6. The molded case circuit breaker according to claim 5, characterized in that: The third circuit board (662) is also provided with a third connector which is plugged into and matched with the wireless communication module (65).

7. The molded case circuit breaker according to claim 4, characterized in that: The tripping unit (5) comprises an electromagnetic tripper (51) and a sliding member (52) capable of driving the circuit breaker to open. The electromagnetic tripper (51) is arranged on a mounting plate (6). A traction rod (7) is arranged in a contact arc extinguishing region (142). A bracket (8) is fixedly arranged on the mounting plate (6). A reset spring (9) is arranged between the sliding member (52) and the bracket (8). A driving block (521) is arranged on the sliding member (52). When the output end of the electromagnetic tripper (51) is retracted, the sliding member (52) slides forward under the action of the reset spring (9), and the driving block (521) presses against the traction rod (7) to drive the traction rod (7) to rotate, thereby realizing the tripping and opening of the circuit breaker.

8. The molded case circuit breaker according to claim 2, characterized in that: A mounting frame (10) is provided in the transformer installation area (143), and at least three mounting slots (11) are provided on the mounting frame (10), and a current transformer (101) is provided in each mounting slot (11), and the output end of each phase current transformer (101) is electrically connected to the first circuit board (63), and a guide slot is provided on the side wall of each mounting slot (11) along the vertical direction thereof, for sliding the iron core of each current transformer (101) when the current transformer (101) is installed.

9. The molded case circuit breaker according to claim 7, characterized in that: The electromagnetic release (51) comprises a coil (511) and a locking member (512), wherein the coil (511) is fixedly arranged on a bracket (8), the locking member (12) is hingedly arranged on the bracket (8) via a torsion spring, and the locking member (512) comprises a resisting arm (5121) and a locking arm (5122), wherein the resisting arm (5121) is arranged corresponding to the moving iron core of the coil (511), and a locking opening (522) is arranged on the sliding member (52), and the sliding member (52) slides so that the locking opening (522) on the sliding member (52) is locked by the locking arm (5122), and the working moving iron core of the coil (511) moves to push the resisting arm (5121), so that the locking arm (5122) is released.

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