Contact unit and rotary isolation switch

Abstract

A contact unit and a rotary isolation switch are provided. The contact unit includes a shell and a contact mechanism arranged in the shell. The contact mechanism includes a pair of static contact assemblies and a moving contact assembly. Each stationary contact assembly includes a stationary contact portion. Arc extinguishing systems are arranged on both sides of the contact mechanism. Each arc extinguishing system includes an arc extinguishing cover. One end of the arc extinguishing cover is used as an arc inlet. The contact mechanism also includes a housing. An accommodating cavity of the housing is provided with two opposing openings. Each opening is connected to one arc inlet. The moving contact assembly and the stationary contact portions are assembled in the accommodating cavity, and the moving contact assembly is located between a pair of stationary contact portions. The contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space. In the present invention, the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space, so that an electric arc generated by the contact mechanism flows in the relatively closed space, thereby improving arc striking and arc extinguishing effects.

Description

[0001] The present application claims priority to Chinese Patent Application No. 202310761027.1 filed on June 26, 2023, and Chinese Patent Application No. 202310761480.2 filed on June 26, 2023, both of which are incorporated herein in their entireties by reference.Technical Field

[0002] The present invention relates to the field of switching electrical appliances, in particular to a contact unit and a rotary isolation switch.Background

[0003] With the rapid development of Alternating Current (AC) and Direct Current (DC) electrical appliance industry, rotary isolation switches have been widely used. The isolation switch is a switching device that has both an isolation function and a switching function. The traditional rotary isolation switch is generally provided with an operating module and a contact module driven by the operating module, wherein the contact module includes a plurality of contact units which are laminated, and each contact unit is generally provided with a contact mechanism and an arc extinguishing system. The existing contact unit generally has the following defects: firstly, there are many contact mechanism components, resulting in inconvenience of assembly; secondly, the arc extinguishing system is limited by space, resulting in poor arc extinguishing effect; thirdly, the cooperation between the contact mechanism and the arc extinguishing system is more complicated, resulting in poor arc striking effect; and fourthly, the internal layout of the contact unit is complicated, and especially, the contact mechanism and the arc extinguishing system do not have a modular structure, making the assembly cumbersome and unable to meet the modular development of the isolation switch.Summary

[0004] An object of the present invention is to overcome at least one defect of the prior art and provide a contact unit and a rotary isolation switch, which have simple structure and high reliability.

[0005] In order to achieve the above objective, the present invention provides the following technical solution:

[0006] The present invention provides a contact unit, comprising a shell and a contact mechanism arranged in the shell, in which the contact mechanism comprises a pair of static contact assemblies and a moving contact assembly; each stationary contact assembly comprises a stationary contact portion; arc extinguishing systems are arranged on both sides of the contact mechanism; each arc extinguishing system comprises an arc extinguishing cover; one end of the arc extinguishing cover is used as an arc inlet; and

[0007] the contact mechanism further comprises a housing; an accommodating cavity of the housing is provided with two opposing openings; each opening is connected to one arc inlet; the moving contact assembly and the stationary contact portions are assembled in the accommodating cavity; the moving contact assembly is located between a pair of stationary contact portions; and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space.

[0008] Preferably, the arc extinguishing cover is open at both ends, one open end is used as the arc inlet, and the other open end is abutted against and closed by the shell; or the arc extinguishing cover is open at one end and closed at the other end, and the open end is used as the arc inlet.

[0009] Preferably, the moving contact assembly comprises a rotating shaft and a moving contact bridge arranged along a radial direction of the rotating shaft; the rotating shaft rotates between a pair of stationary contact portions; both ends of the moving contact bridge are used as moving contact portions which cooperate with the stationary contact portions; and the moving contact assembly cooperates with the accommodating cavity to block two openings from being communicated with each other.

[0010] Preferably, a circumferential side wall of the rotating shaft is provided with two opening limiting portions in a protruding manner; two opening barrier portions are arranged in the accommodating cavity; the opening barrier portions are located on a rotation trajectory of the opening limiting portions; each opening limiting portion is adjacent to one moving contact portion; when the rotating shaft rotates to an opening position, the opening limiting portions are in limiting fit with the opening barrier portions; and the rotating shaft, the two opening limiting portions and the two opening barrier portions block two openings from being communicated with each other.

[0011] Preferably, one stationary contact portion and one opening barrier portion are located on both sides of the same opening of the housing; one moving contact portion and one opening limiting portion jointly rotate between one stationary contact portion and one opening barrier portion; and the opening limiting portion is located on a side of the moving contact portion away from the stationary contact portion.

[0012] Preferably, the housing is of an integrated structure; alternatively, the housing comprises two plate bodies which are spaced oppositely; the two plate bodies are encircled to form a hollow cavity body which is open at both ends; a hollow part of the hollow cavity body is used as the accommodating cavity; splicing structures which cooperate with each other are arranged between the two plate bodies; and the splicing structures enable the two plate bodies to form an integral body that can be split in a pluggable manner.

[0013] Preferably, the housing comprises two plate bodies which are spaced oppositely; extensions are arranged on the edges of both sides of each plate body; the extensions on the same sides of the two plate bodies cooperate with each other to form connecting walls of the housing; each connecting wall is provided with an assembling groove and one opening barrier portion; and the middle parts of the two plate bodies are used as a pair of supporting walls.

[0014] Preferably, the arc extinguishing system further comprises a buffer area; the arc extinguishing cover is open at both ends; one open end of the arc extinguishing cover is used as the arc inlet; a side wall of the arc extinguishing cover adjacent to the arc inlet is provided with a plurality of exhaust holes; the arc inlet is communicated with the contact mechanism in a first direction of the shell; the buffer area and the arc extinguishing cover are arranged along a second direction of the shell; the buffer area is joined with the exhaust holes; and the first direction is perpendicular to the second direction.

[0015] Preferably, each arc extinguishing system comprises two buffer areas; in the second direction, the two buffer areas are located on both sides of the arc extinguishing cover; each buffer area is provided with a plurality of upright columns, which are opposite to the exhaust holes, along a third direction; and the third direction is perpendicular to the first direction and the second direction, respectively.

[0016] Preferably, baffles are also arranged around the arc extinguishing chamber; the baffles are spaced opposite to the exhaust holes of an arc extinguishing chamber, so that a space of the housing between the baffle and the exhaust hole forms the buffer area; the plurality of upright columns are arranged in at least two rows; the plurality of upright columns in each row are arranged equidistantly in the first direction; and the upright columns in adjacent rows are misaligned against each other.

[0017] Preferably, each arc extinguishing system comprises an arc extinguishing chamber, the arc extinguishing chamber comprises an arc extinguishing cover and two grid groups which are spaced within the same arc extinguishing cover, and an arc running channel which is communicated with the arc inlet is arranged between the two grid groups; alternatively, the arc extinguishing system comprises two arc extinguishing chambers, each arc extinguishing chamber comprises an arc extinguishing cover and a grid group arranged within the arc extinguishing cover, an opening is formed in a side of each arc extinguishing cover adjacent to the arc inlet, openings of the two arc extinguishing covers are opposite each other, an arc extinguishing groove of each grid group is communicated with the arc inlet, the arc extinguishing groove of each grid group is opposite to the opening, and a spacing between the two grid groups forms the arc running channel which is communicated with the arc inlet.

[0018] Preferably, each arc extinguishing system further comprises a short-circuiting plate; the short-circuiting plate is arranged at an end of the arc running channel away from the arc inlet; the short-circuiting plate comprises two pins and an arc striking plate; the two pins extend toward one ends of the two grid groups away from the arc inlet respectively, so that an electric clearance between one ends of the two grid groups away from the arc inlet is less than a minimum physical distance between the two grid groups; and the arc striking plate extends along a center line of the arc running channel toward a direction close to the arc inlet.

[0019] Preferably, one arc extinguishing grid in each grid group away from the arc inlet is a tail grid, the tail grids in the two grid groups are connected, and the tail grids in the two grid groups protrude toward the arc inlet to form an arc striking portion for bridging electric arcs; or

[0020] a connecting grid group is arranged at an end of the arc running channel away from the arc inlet, the connecting grid group comprises a plurality of connecting grids which are spaced, and the plurality of connecting grids are arranged along a straight line, an arc line or a fold line connected between the two connecting grid groups.

[0021] Preferably, each arc extinguishing system further comprises at least two magnetic conduction plates which are spaced, each magnetic conduction plate is arranged outside the arc extinguishing cover, the arc running channel is located between the at least two magnetic conduction plates, and a magnetic field is formed by the magnetic conduction plates in the arc running channel.

[0022] The present invention further provides a rotary isolation switch, comprising an operating module and a contact module, in which the contact module comprises at least one contact unit as above-mentioned, and the at least one contact unit is driven by an operating mechanism of the operating module for opening and closing.

[0023] According to the contact unit and the rotary isolation switch of the present invention, the contact mechanism and each of the arc extinguishing systems form a modular structure, which is convenient for assembly and also meets the modular development of the isolation switch. Meanwhile, a housing of the contact mechanism is docked with an arc inlet of an arc extinguishing cover, and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space, so that an electric arc generated by the contact mechanism flows within a relatively closed space, thereby improving arc striking and arc extinguishing effects.

[0024] In addition, the cooperation between the moving contact assembly and the accommodating cavity can prevent the communication between the two openings of the housing, and the accommodating cavity is divided into two relatively independent parts, thereby avoiding the interaction between the two arc extinguishing systems through the accommodating cavity, and at the same time increasing an airtightness effect.

[0025] In particular, the cooperation between the opening limiting portions of the rotating shaft and the opening barrier portions of the housing can not only play a limiting role during opening, but also increase the air tightness and creepage distance.

[0026] In addition, the arc extinguishing systems form a relatively closed space through the arc extinguishing cover, and then equipped with two grid groups, which facilitates improving their arc extinguishing ability.

[0027] In addition, each arc extinguishing system is also provided with a short-circuiting plate, which makes an electric clearance between one ends of the two grid groups away from the arc inlet is less than a minimum physical distance between the two grid groups, thereby increasing the utilization rate of the arc extinguishing grids in the grid groups and improving the arc extinguishing effect.

[0028] In addition, each arc extinguishing system is also provided with magnetic conduction plates, and the arc running channel is provided between the magnetic condition plates, so that the magnetic conduction plates cooperate with each other in the arc running channel to form a magnetic field, which is conducive to introducing the electric arc into the grid groups and improving the arc quenching ability.

[0029] In addition, a plurality of upright columns are provided in a buffer area to cool and adsorb exhaust gas, so that the exhaust gas is cooled and absorbed in the buffer area, avoiding the exhaust gas from being discharged from the shell and improving the safety in use.Brief Description of the Drawings

[0030] FIG. 1 is a schematic structural diagram of a contact unit in the present invention; FIG. 2 is a schematic structural diagram (in a closed state) of a contact mechanism and an arc extinguishing chamber in the present invention; FIG. 3 is a schematic structural diagram (in an opened state) of the contact mechanism and the arc extinguishing chamber in the present invention; FIG. 4 is a schematic diagram of electric arc flowing when the contact mechanism is opened in the present invention; FIG. 5 is a schematic structural diagram of the contact mechanism in the present invention; FIGS. 6-7 are schematic exploded views of the contact mechanism in the present invention; FIG. 8 is a schematic structural diagram showing a side of a plate body facing an accommodating cavity in the present invention; FIG. 9 is a schematic structural diagram of a side of the plate body away from the accommodating cavity in the present invention; FIGS. 10-11 are schematic structural diagrams of a rotating shaft and a moving contact bridge in the present invention; FIG. 12 is a schematic structural diagram of the disassembled rotating shaft and the moving contact bridge in the present invention; FIG. 13 is a schematic structural diagram showing a side of a contact support facing a cover plate in the present invention; FIG. 14 is a schematic structural diagram showing a side of the contact support away from the cover plate in the present invention; FIG. 15 is a schematic structural diagram showing a side of the cover plate facing the contact support in the present invention; FIG. 16 is a schematic structural diagram showing a side of the cover plate away from the contact support in the present invention; FIG. 17 is a schematic structural diagram of the moving contact bridge in the present invention; FIG. 18 is a schematic structural diagram of a moving contact piece and an elastic member in the present invention; FIG. 19 is a schematic structural diagram of the moving contact piece in the present invention; FIG. 20 is a side view of the moving contact piece in the present invention; FIG. 21 is a schematic structural diagram of the elastic member in the present invention; FIG. 22 is a schematic structural diagram of a supporting member in the present invention; FIGS. 23-24 are schematic structural diagrams of the arc extinguishing chamber in the present invention; FIGS. 25-26 are schematic structural diagrams of a cover body, a grid group and a short-circuiting plate in the present invention; FIG. 27 is a schematic structural diagram of the cover body in the present invention; FIG. 28 is a schematic structural diagram of a grid slot formed in the cover body in the present invention; FIG. 29 is a schematic structural diagram of the grid group in the present invention; FIG. 30 is a schematic structural diagram of the short-circuiting plate in the present invention; FIG. 31 is a schematic structural diagram of a magnetic conduction plate in the present invention; FIG. 32 is a schematic structural diagram of the contact unit in the present invention; and FIG. 33 is a schematic structural diagram of a shell in the present invention.

[0031] Reference symbols represent the following components: a-contact mechanism, 1-moving contact assembly, 11-rotating shaft, 111-contact support, 1111-radial groove, 112-cover plate, 1121-through hole, 113-rotating portion, 114-transmission shaft, 115-opening limiting portion, 116-snap-fit groove, 117-transmission groove, 12-moving contact bridge, 120-moving contact portion, 1201-clamping clearance, 121-moving contact piece, 1210-guide piece, 1211-limiting groove, 1212-positioning hole, 122-elastic member, 1221-elastic arm, 1222-elastic opening, 123-supporting member, 1231-body, 1232-camshaft, 13-fastener, 2-stationary contact assembly, 21-stationary contact portion, 22-wiring portion, 3-housing, 301-plate body, 302-supporting wall, 303-connecting wall, 304-extension, 31-assembling groove, 32-opening barrier portion, 33-communicating hole, 341-first limiting portion, 342-second limiting portion, 351-buckle, 352-clamping groove, 361-positioning groove, 40-arc extinguishing chamber, 401-arc inlet, 402-arc running channel, 41-grid group, 410-arc extinguishing groove, 411-arc extinguishing grid, 412-arc extinguishing notch, 42-arc extinguishing cover, 421-cover body, 422-docking portion, 423-exhaust hole, 424-grid slot, 4251-magnetic conduction plate mounting groove, 4252-fastening boss, 4261-first boss, 4262-second boss, 427-engagement groove, 43-magnetic conduction plate, 431-fastening groove, 44-short-circuiting plate, 441-pin, 442-arc striking plate, 45-buffer area, 451-upright column, 5-shell, 511-first matching portion, 512-second matching portion, 52-baffle, 521-straight segment, 522-joining segment, 53-limiting plate, 531-notch, 54-central hole, and 55-engagement portion.DETAILED DESCRIPTION

[0032] The specific implementations of a contact unit and a rotary isolation switch of the present invention will be further described below in conjunction with the embodiments given in the accompanying drawings. The contact unit and the rotary isolation switch of the present invention are not limited to the description of the following embodiments.

[0033] The rotary isolation switch includes an operating module and a contact module which are laminated. The contact module includes at least one contact unit. The two adjacent contact units are connected in a linkage manner. The at least one contact unit is driven by an operating mechanism of the operating module for opening and closing.

[0034] Specifically, as shown in FIG. 1, each contact unit includes a shell 5. A contact mechanism a, two arc extinguishing systems and a pair of wiring assemblies (not shown) are arranged in the shell 5. The contact mechanism a includes a moving contact assembly 1 and a pair of static contact assemblies 2. Each stationary contact assembly 2 is connected to one wiring assembly. The moving contact assembly 1 rotates between the pair of static contact assemblies 2 for turning on or off a main line in each contact unit. The moving contact assembly 1 includes a rotating shaft 11 and a pair of moving contact portions 120 arranged in the rotating shaft 11. The rotating shaft 11 is rotatably arranged between the pair of static contact assemblies 2. A moving contact bridge 12 is arranged in the rotating shaft 11. Both ends of the moving contact bridge 12 serve as the moving contact portions 120. Each moving contact portion 120 extends along a radial direction of the rotating shaft 11 out of the rotating shaft 11. As the rotating shaft 11 is driven to rotate, each moving contact portion 120 is in contact with or separated from one stationary contact assembly 2. The two adjacent contact units are connected in a linkage manner through the rotating shaft 11, so that the contact mechanisms a in all contact units can be synchronously opened and closed.

[0035] Each arc extinguishing system is fitted on a side of the contact mechanism a, and used to extinguish an electric arc generated when the contact mechanism a is opened. The arc inlet 401 of the arc extinguishing system 401 is joined with the contact mechanism a. Each arc extinguishing system includes an arc extinguishing cover 42 and a grid group 41 arranged in the arc extinguishing cover 42. The electric arc generated when the contact mechanism a is turned off is introduced from the arc inlet 401 of the arc extinguishing cover 42. The electric arc is cut by the grid group 41 to extinguish the electric arc.

[0036] As shown in FIGS. 1-4, an improvement point of the present application lies in that the arc extinguishing system includes an arc extinguishing cover 42, and one end of the arc extinguishing cover 42 serves as the arc inlet 401; the contact mechanism a also includes a housing 3; an accommodating cavity of the housing 3 is provided with two opposing openings; each opening is correspondingly connected to one arc inlet 401; the moving contact assembly 1 and the stationary contact portions 21 are assembled in the accommodating cavity; the moving contact assembly 1 is located between a pair of stationary contact portions 21; and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space. In this way, the contact mechanism a and each of the arc extinguishing systems form a modular structure, which is convenient for assembly and also meets the modular development of the isolation switch. Meanwhile, the housing 3 of the contact mechanism a is docked with the arc inlet 401 of the arc extinguishing cover 42, and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space, so that the electric arc generated by the contact mechanism a flows within the relatively closed space, thereby improving arc striking and arc extinguishing effects.

[0037] Specifically, as shown in FIG. 5, the housing 3 is provided with a pair of opposing openings. The two pairs of side walls of the housing 3 connected between the pair of openings are a pair of supporting walls 302 and a pair of connecting walls 303, respectively. Each connecting wall 303 is adjacent to one supporting wall 302. The stationary contact portions 21 of each stationary contact assembly 2 are arranged on one connecting wall 303, and the two stationary contact portions 21 are spaced and misaligned to face each other. The moving contact assembly 1 includes a rotating shaft 11 and a moving contact bridge 12 arranged along a radial direction of the rotating shaft 11, wherein the rotating shaft 11 is rotatably supported between the pair of supporting walls 302. That is, the rotating shaft 11 is rotatably supported between the pair of stationary contact portions 21, both ends of the moving contact bridge 12 serve as the moving contact portions 120, and each moving contact portion 120 moves between the pair of connecting walls 303 for cooperation with one stationary contact portion 21.

[0038] Specifically, the arc extinguishing cover 42 is open at both ends. An internal space of the arc extinguishing cover 42 forms an arc extinguishing cavity. One open end of the arc extinguishing cover 42 is used as the arc inlet 401, and the other open end is abutted against and closed by the shell 5. At least one grid group 41 is arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. Each grid group 41 includes a plurality of arc extinguishing grids 411 which are spaced oppositely. An arc extinguishing clearance is formed between every two adjacent arc extinguishing grids 411. A plurality of exhaust holes 423 are formed in a side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401. The exhaust holes 423 are communicated with the arc extinguishing clearance. When the arc inlet 401 is docked with the opening of the housing 3, the arc extinguishing cavity is docked with the accommodating cavity of the housing 3 to form a relatively closed space, thereby improving arc triggering and arc extinguishing effects. Of course, the arc extinguishing cover 42 may also adopt a structure where one end is closed and the other end is open, wherein the open end of the arc extinguishing cover 42 is used as the arc inlet 401, and the closed end may be docked with the shell 5 to achieve limited assembly.

[0039] Further, the moving contact assemblies 1 cooperate with the accommodating cavity to block the two openings from being communicated with each other. For example, the rotating shaft 11 is abutted against an inner side wall of the accommodating cavity, but may affect its rotational smoothness. Preferably, a limiting portion and a barrier portion which cooperate with each other are arranged between the rotating shaft 11 and the accommodating cavity. The limiting portion and the barrier portion block the two openings from being communicated with each other when the rotating shaft 11 rotates to an opening position, which enables the accommodating cavity to be separated into two independent parts while ensuring the rotational smoothness, thereby avoiding the two arc extinguishing systems from interfering with each other through the accommodating cavity.

[0040] Specifically, as shown in FIGS. 7, and 10-12, a circumferential side wall of the rotating shaft 11 is provided with two opening limiting portions 115, opening barrier portions 32 are arranged in the accommodating cavity, and the opening barrier portions 32 are located on a trajectory of the opening limiting portions 115. When the rotating shaft 11 rotates to the opening position, the opening limiting portions 115 are in limiting fit with the opening barrier portions 32, and the rotating shaft 11 and the two opening limiting portions 115 block two openings from being communicated with each other, which can not only play a role of mutual limiting in the opening process, but also increase the air tightness and creepage distance between the arc extinguishing system and the contact mechanism a.

[0041] Further, as shown in FIGS. 25 and 26, each arc extinguishing system includes an arc extinguishing cover 42 and two grid groups 41 which are spaced. The arc extinguishing cover 42 is open at both ends, wherein one open end serves as the arc inlet 401, and the other open end opposite the arc inlet 401 is closed by the shell 5, preferably assembled in the shell 5 and closed by an inner side wall of the shell 5. Of course, the other open end of the arc extinguishing cover 42 is closed by a partition plate arranged in the shell 5, or the arc extinguishing cover 42 may also adopt a structure where one end is closed and the other end is open. Therefore, a relatively closed arc extinguishing cavity is formed inside the arc extinguishing cover 42. The grid groups 41 are arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. An arc extinguishing chamber 40 is formed by the arc extinguishing cover 42 and the grid groups 41 arranged in the arc extinguishing cover 42. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41. The electric arc enters each grid group 41 through the arc inlet 401 and the arc running channel 402. The electric arc is cut by arc extinguishing grids 411 in each grid group 41. A side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401 is provided with a plurality of exhaust holes 423. Exhaust gas generated after the electric arc is cut is discharged from the exhaust holes 423.

[0042] Preferably, as shown in FIGS. 23-26, each arc extinguishing system further includes a short-circuiting plate 44 and / or at least two magnetic conduction plates 43. The short-circuiting plate 44 is arranged at one end of the arc running channel 402 away from the arc inlet 401. The short-circuiting plate 44 enables an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401 to be less than a minimum physical distance between the two grid groups 41. In other words, a distance between one end of each grid group 41 away from the arc inlet and one pin 441 of the short-circuiting plate 44 is less than a minimum physical spacing between the two grid groups 41. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited by means of the short-circuiting plate 44, so that an electric arc current needs to break through the arc extinguishing grids 411 in each grid group 41 before forming a current loop, thereby increasing the utilization rate of the arc extinguishing grids 411 in each grid group 41. Of course, the utilization rate of the arc extinguishing grids 411 can also be increased by using other ways to enable one ends of the two grid groups 41 away from the arc inlet 401 to be equipotentially short-circuited.

[0043] Preferably, the number of magnetic conduction plates 43 is at least two, and the magnetic conduction plates 43 are paired and spaced, so that the arc running channel 402 is located between the at least two magnetic conduction plates 43. After the magnetic conduction plates 43 are magnetized, a magnetic field is correspondingly formed by the magnetic conduction plates 43 in the arc running channel 402. This magnetic field direction is preferably perpendicular to a connecting line between the two grid groups 41, such that the electric arc entering the arc running channel 402 is introduced into the grid groups 41 under the action of the magnetic field, thereby improving the arc quenching ability. The magnetic conduction plates 43 may be embedded in a side wall of the arc extinguishing cover 42, or may be arranged on the surface of an inner side wall of the arc extinguishing cover 42. That is, the magnetic conduction plates 43 are located in the arc extinguishing cavity, but are prone to electric arc stagnation. Preferably, the magnetic conduction plates 43 are arranged on the outer surface of the side wall of the arc extinguishing cover 43, that is, the magnetic conduction plates 43 are located outside the arc extinguishing cavity.

[0044] A specific embodiment of a contact unit is provided in conjunction with FIGS. 1-31.

[0045] As shown in FIGS. 1-4, the contact unit includes a shell 5. A contact mechanism a is arranged in the middle of the shell 5. Arc extinguishing systems are fitted on both sides of the contact mechanism a. The two arc extinguishing systems form a rotationally symmetrical structure with respect to the contact mechanism a. The contact mechanism a includes a housing 3. An accommodating cavity of the housing 3 is provided with two opposing openings. Each arc extinguishing system includes an arc extinguishing cover 42. The arc extinguishing cover 42 is open at one end and closed at the other end, so that a relatively closed arc extinguishing cavity is formed inside the arc extinguishing cover 42. The open end of each arc extinguishing cover 42 is used as the arc inlet 401. Each arc inlet 401 is docked with one opening of the housing 3. That is, the two openings of the housing 3 are seamlessly connected to the open end of the arc extinguishing cover 42 on the same side, such that the arc extinguishing cavity and the accommodating cavity are connected together in an approximately sealed manner to form a relatively closed space. The other open end away from the arc inlet 401 is closely clung to the inner side wall of the shell 5, and is closed by the inner side wall of the shell 5 or by the partition plate arranged in the shell 5, so that one end of the arc extinguishing cavity away from the arc inlet 401 is closed. Of course, when the arc extinguishing cover 42 is a structure where one end is closed and the other end is open, the closed end is closely clung to the inner side wall of the shell 5 to achieve limited installation.

[0046] As shown in FIGS. 5-22, the moving contact assembly 1 includes a rotating shaft 11 and a moving contact bridge 12. The rotating shaft 11 is rotatably supported in the accommodating cavity between the two openings. The moving contact bridge 12 is arranged in the rotating shaft 11 along a radial direction of the rotating shaft 11. Both ends of the moving contact bridge 12, which serve as the moving contact portions 120, extend out of the rotating shaft 11 along the radial direction of the rotating shaft 11. In this embodiment, each moving contact portion 120 corresponds to one opening. That is, when the moving contact assembly 1 rotates to be opened and closed, each moving contact portion 120 moves from one side of one opening to the other side of the same opening. In this process, a partial region of each moving contact portion 120 may extend out of the corresponding opening, that is, move within the open end, which can also be understood that the moving contact portions 120 can partially move within the arc inlet 401.

[0047] Specifically, as shown in FIGS. 5-9, two pairs of side walls of the housing 3 connected between the two openings are a pair of supporting walls 302 and a pair of connecting walls 303, respectively. Each connecting wall 303 is adjacent to one supporting wall 302. A communicating hole 33 is formed in the middle of the pair of supporting walls 302. The rotating shaft 11 is rotatably supported between the pair of connecting walls 303, and each communicating hole 33 is coaxial with the rotating shaft 11. An output shaft of the operating mechanism or a transmission shaft 114 of the adjacent two contact units may pass through the communicating hole 33 and drives the rotating shaft 11 to rotate. A first limiting portion 341 is arranged on the outer surface of each supporting wall 302 in a protruding manner. In this embodiment, as shown in FIGS. 5-9, the first limiting portion 341 is an annular boss surrounding the communicating hole 33, and a second limiting portion 342 is arranged on the outer surface of the connecting walls 303. The second limiting portion 342 in FIGS. 7 and 9 is a strip-shaped groove, and a central axis of the strip-shaped groove is parallel to a central axis of the communicating hole 33. Correspondingly, a first matching portion and a second matching portion are arranged in the shell 5 in which the moving contact assembly 1 is assembled. Specifically, the first matching portion is preferably an annular groove. A central hole is generally formed in the middle of the shell 5. The first matching portion is arranged around the edge of the central hole, and the second matching portion is a convex strip-shaped boss. The first matching portion and the first limiting portion 341 limit the moving contact assembly 1 parallel to an axial direction of the rotating shaft 11, and the second matching portion and the second limiting portion 342 limit the contact mechanism a perpendicular to the axial direction of the rotating shaft 11, which is conducive to ensuring the stability of their assembly.

[0048] In this embodiment, as shown in FIGS. 5-9, the housing 3 includes two plate bodies 301 which are spaced oppositely. The two plate bodies 301 may have the same shape, or different shapes. However, the two plate bodies 301 are encircled to form a hollow cavity body with two open ends. The hollow cavity body as a whole is a "□"-shaped cavity body. A hollow part of the hollow cavity body is used as the accommodating cavity. The two plate bodies 301 may be formed by cooperation of "-" and "" shapes, or may be formed by encircling of two ""-shaped plate bodies 301, or may both be "" shaped.

[0049] As shown in FIGS. 8 and 9, in this embodiment, it is preferred that each plate body 301 has a rectangular plate structure as a whole. Protruding extensions 304 are arranged on both sides of a plate surface of each plate body 301, so that each plate body 301 is in a "" shape. A pair of connecting walls 303 of the housing 3 are formed by cooperation of the extensions 304 on the same side of two plate bodies 301. The two extensions 304 may be lapped or docked to form the connecting walls 303, and the middle parts of the two plate bodies 301 are spaced oppositely to form a pair of supporting walls 302 of the housing 3.

[0050] Further, as shown in FIGS. 7 and 8, splicing structures which cooperate with each other are arranged between the two plate bodies 301. Each splicing structure includes at least a pair of buckle 351 and a clamping groove 352 which cooperate with each other. One plate body 301 is provided with a clamping groove 352 and / or a buckle 351, and the other plate body 301 is provided with a buckle 351 and / or a clamping groove 352. In this embodiment, the clamping groove 352 is formed in the middle of each of the two extensions 304 of one plate body 301, and the buckle 351 is arranged in the middle of each of the two extensions 304 of the other plate body 301 in a protruding manner. When the two extensions 304 are docked to form the connecting walls 303, the buckle 351 and the clamping groove 352 cooperate with each other to form a pluggably detachable structure, which is convenient for the assembly of the rotating shaft 11 in the accommodating cavity.

[0051] As shown in FIGS. 7 and 8, a groove structure serving as the opening barrier portion 32 is arranged at the edge of each extension 304. Each groove structure is an arc-shaped groove and has an opening which is inclined to open toward the housing 3, so that the edge of each extension 304 forms an "S" shape. A central line of each groove structure coincides with a part of movement trajectory of the opening limiting portions 115. In this embodiment, the two opening barrier portions 32 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33.

[0052] Preferably, each connecting wall 303 is provided with an assembling groove 31, each stationary contact assembly 2 cooperates with the moving contact assembly 1 through the assembling groove 31, and the two assembling grooves 31 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33. In this embodiment, the groove structure is formed in the edge of the end surface of each extension 304. When the two extensions 304 are docked, the two groove structures cooperate with each other to form the assembling groove 31. Each assembling groove 31 is located in the middle of the connecting wall 303, and the same connecting wall 303 is provided with one assembling groove 31 and one opening barrier portion 32. That is, one stationary contact portion 21 and one opening barrier portion 32 are located on the connecting walls 303 on both sides of the same opening of the housing 3, and the stationary contact assembly 2 can be clamped when the two extensions 304 are docked, thereby achieving stable fit of the stationary contact assembly 2 and the housing 3.

[0053] Of course, the housing 3 may also not be provided with an assembling groove 31, and the stationary contact assembly 2 extends from the opening of the housing 3 into the housing 3 to cooperate with the moving contact assembly 1, but may affect the fit airtightness of the housing 3 and the arc extinguishing cover 42.

[0054] Further, at least one group of positioning structures may also be arranged between the two plate bodies 301. Each positioning structure includes a positioning boss (not shown) and a positioning groove 361. One of the plate bodies 301 is provided with a positioning boss and / or a positioning groove 361, while the other plate body 301 is provided with a positioning groove 361 and / or a positioning boss. In this embodiment, the two extensions 304 of one of the plate bodies 301 are respectively provided with one positioning groove 361, and the two positioning grooves 361 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33. That is, the two positioning grooves 361 in FIG. 8 are located at the corners of the same plate body 301, respectively. The two extensions of the two plate bodies 301 are respectively provided with one positioning boss, and each positioning boss is positioned in cooperation with one positioning groove 361, thereby facilitating assembly.

[0055] In addition, the two extensions 304 may be fixed together, for example, by screws, or adhered by hot riveting, ultrasonic riveting and other processes. At this time, the two extensions 304 may be docked through end surfaces or come into contact through side surfaces, which can ensure the stability of the housing 3, but is not convenient for disassembly and assembly. In this case, it is necessary to provide assembling grooves 31 in the connecting walls 303.

[0056] Of course, the housing 3 may also be of an integrated structure (see FIG. 5), in which case the connecting walls 303 are of an integrated structure, the assembling groove 31 is directly formed in the middle of the connecting wall 303, and the opening barrier portion 32 is arranged at the same position in the accommodating cavity.

[0057] In this embodiment, an axial height of the rotating shaft 11 is greater than or equal to a spacing between a pair of supporting walls 302. A circumferential side wall of the rotating shaft 11 is provided with two opening limiting portions 115 in a protruding manner. The rotating shaft 11 and the two opening limiting portions 115 block the two openings of the accommodating cavity from being communicated with each other. Preferably, both ends of the rotating shaft 11 are rotatably abutted against the supporting walls 302. That is, rotating surfaces of the rotating shafts 11 are rotatably abutted against the supporting walls 302 to limit the axial movement of the rotating shaft 11, thereby closing a clearance between the rotating shaft 11 and the communicating hole 33. When the rotating shaft rotates to the opening position, the two opening limiting portions 115 are abutted against the accommodating cavity (an inner side wall of the housing 3) to block the two openings from being communicated with each other. Further, the opening barrier portions 32 are arranged in the accommodating cavity. The opening barrier portions 32 are located on a movement trajectory of the opening limiting portions 115. When the rotating shaft 11 rotates to the opening position, the opening limiting portions 115 and the opening barrier portions 32 cooperate with each other to limit the rotating shaft 11 from further rotation. The thickness of the opening limiting portion 115 and / or the opening barrier portion 32, or, the overall thickness of the opening limiting portion 115 and the opening barrier portion 32 after cooperation is equal to a distance between the pair of supporting walls 302. Therefore, the two openings of the accommodating cavity are blocked from being communicated with each other, thereby achieving the effects of airtight guidance and increasing the creepage distance.

[0058] Of course, when the opening limiting portions 115 are not used to block the communication of the two openings of the housing 3, the opening limiting portions 115 may also be arranged in other positions of the rotating shaft 11. For example, the opening limiting portions 115 are arranged on the rotating surface of the rotating shaft 11. In this case, each opening barrier portion 32 is an arc-shaped trajectory groove formed in the supporting wall 302, and the opening of the arc-shaped trajectory groove faces the opening limiting portion 115. After the rotating shaft 11 rotates to the opening position, the opening limiting portion 115 is abutted against a closed end of the arc-shaped trajectory groove.

[0059] As shown in FIGS. 6, 7, and 10-16, the rotating shaft 11 is cylindrical as a whole. The two moving contact portions 120 extend along the radial direction of the rotating shaft 11 out of the rotating shaft 11, and the circumferential side wall of the rotating shaft 11 is provided with the opening limiting portions 115 in a protruding manner. Two opening limiting portions 115 are shown in FIGS. 1, 11 and 12, respectively. The two opening limiting portions 115 form a rotationally symmetrical structure with respect to an axis of the rotating shaft 11, and each opening limiting portion 115 is adjacent to one moving contact portion 120, so as to avoid a large clearance between the opening limiting portion 115 and the moving contact portion 120 to limit a rotation angle of the rotating shaft 11. As the rotating shaft 11 rotates in the housing 3, each moving contact portion 120 and the opening limiting portion 32 adjacent to the moving contact portion 120 move together between the stationary contact portion 21 and the opening barrier portion 32 on both sides of the same opening. During opening, the opening limiting portion 115 is located on a side of the moving contact portion 120 away from the stationary contact portion 21.

[0060] A specific structure of a split rotating shaft 11 is provided in conjunction with FIGS. 7, and 10-12. The rotating shaft 11 includes a contact support 111, and a cover plate 112 covering the contact support 111.

[0061] As shown in FIGS. 10-14, the contact support 111 is cylindrical as a whole. A radial groove 1111 is formed in the surface on one side of the contact support 111. The radial groove 111 is open at both ends. The moving contact bridge 12 is assembled in the radial groove 1111, and both ends of the moving contact bridge 12 extend out of the contact support 111 to form two moving contact portions 120. Two transmission shafts 114 are formed on both sides of the radial groove 111 in a protruding manner. The transmission shafts 114 can also provide a certain limiting effect on the moving contact bridge 12. Two bosses serving as the opening limiting portions 115 are arranged on a circumferential side wall of the contact support 111 in a protruding manner. The two bosses form a rotationally symmetrical structure with respect to the axis of the contact support 111, and each boss is located immediately adjacent to the open side of the radial groove 1111. A rotating portion 113 is arranged on the surface of the other side of the contact support 111 in a protruding manner. The rotating portion 113 is located in the center position of the contact support 111. The rotating portion 113 is in running fit with the communicating hole 33 of one supporting wall 302. A transmission groove 117 is formed in each of both sides of the rotating portion 113, and each transmission groove 117 is coaxial with the corresponding transmission shaft 114. It should be noted that the transmission shafts 114 may also be assembled separately on the contact support 111. The transmission shafts 114 may also not be provided in pairs, but the transmission shafts 114 are preferably located at a position deviating from the axis of the contact support 111, and a plurality of transmission shafts 114 preferably form a rotationally symmetrical structure with respect to the axis of the contact support 111.

[0062] As shown in FIGS. 10-12, 15, and 16, the cover plate 112 is disc-shaped as a whole. Two through holes 1121 are formed in the middle of the cover plate 112. Each through hole 1121 is coaxial with the transmission shaft 114 of the contact support 111. When the cover plate 112 covers the contact support 111, each transmission shaft 114 correspondingly passes through one through hole 1121 and then penetrates out of the housing 3 from the communicating hole 33 of one supporting wall 302, for plugging with the transmission groove 117 of the adjacent moving contact assembly 1. The transmission shafts 114 are located at a position deviating from the axis of the rotating shaft 11, which is conducive to providing a stable linkage connection. Two bosses serving as the opening limiting portions 115 are arranged on the edge of the cover plate 112 in a protruding manner, and each boss located on the cover plate 112 is in one-to-one correspondence to the boss located on the contact support 111. Of course, it is also possible to arrange the bosses serving as the opening limiting portions 115 only on the cover plate 112 or the contact support 111.

[0063] As shown in FIGS. 7, and 1-12, the contact support 111 and the cover plate 112 in this embodiment are connected together through at least one fastener 13. That is, engagement grooves 116 are formed in an edge of one side of the contact support 111 away from the cover plate 112 and an edge of one side of the cover plate 112 away from the contact support 111, respectively. When the cover plate 112 covers the contact support 111, the cover plate 112 corresponds to the engagement groove 116 on the same side of the contact support 111 and is then clamped into the fastener 13. Therefore, the contact support 111 and the cover plate 112 are connected together. In this embodiment, the cover plate 112 and the contact support 111 are connected together through two fasteners 13, the two fasteners 13 are symmetrically arranged on both opposite sides of the rotating shaft 11, and a central connecting line of the two fasteners 13 is perpendicular to a central axis of the moving contact bridge 12. That is, the fasteners 13, the engagement grooves 116 and the transmission shafts 114 are located on the same diameter of the rotating shaft 11, and this diameter is perpendicular to the axis of the moving contact bridge 12.

[0064] In addition, the fasteners 13 and the cover plate 112 or the contact support 111 may be of an integrated structure. For example, the fastener 13 and the cover plate 112 may be of an integrated structure, in which case the engagement groove 116 is only formed in the edge of the contact support 111; or the fastener 13 and the contact support 111 are of an integrated structure, in which case the engagement groove 116 is only formed in the edge of the cover plate 112. It should be noted that the cover plate 112 and the contact support 111 may also be connected by means of other connection ways that facilitate disassembly. In addition, the contact support 111 and the cover plate 112 may also be riveted and fixed by rivets, or welded by hot melting, ultrasonic welding and other processes.

[0065] A specific structure (not shown) of an integrated rotating shaft 11 is provided. The rotating shaft 11 includes a cylindrical rotating body. A radial groove 1111 in which a moving contact bridge 12 is assembled is provided inside the rotating body. Both ends of the radial groove 1111 penetrate through a circumferential side wall of the rotating body, so that two moving contact portions 120 of a moving contact may extend from an open part of the radial groove 1111 out of the rotating body. Opening barrier portions 32 are arranged on a circumferential side wall of the rotating body in a protruding manner. Each opening barrier portion 32 is adjacent to one moving contact portion 120. A rotating portion 113 is arranged at a center position of one side of the rotating body in a protruding manner. The rotating portion 113 is in running fit with the communicating hole 33 of the housing 3. The rotating portion 113 is provided with at least one transmission groove 117, and the transmission groove 117 is located in a position deviating from the axis, for plugging with the transmission shaft 114 of the adjacent moving contact assembly 1. At least one transmission shaft 114 is arranged on the other side of the rotating body in a protruding manner. The transmission shaft 114 is located at a position deviating from the axis of the rotating body. The number of the transmission shafts 114 is preferably two, and the two transmission shafts 114 form a rotationally symmetrical structure with respect to the axis of the rotating shaft 11.

[0066] The moving contact bridge 12 assembled in the rotating shaft 11 may adopt the prior art. That is, the moving contact bridge 12 includes two moving contact pieces 121 which are opposite in parallel. Moving contact portions 120 are correspondingly formed at the same ends of the two moving contact pieces 121, with a clamping clearance 1201 between the two moving contact portions. Each moving contact piece 121 has a certain elasticity and can provide a clamping force for the clamping clearance 1201. Each moving contact portion 120 extends along the radial direction of the rotating shaft 11 out of the rotating shaft 11. As the rotating shaft 11 is driven to rotate, each moving contact portion 120 comes into contact with or is separated from the stationary contact portion 21 of one stationary contact assembly 2.

[0067] Preferably, as shown in FIGS. 12, and 17-20, the moving contact bridge 12 in this embodiment further includes at least two elastic members 122. At least one elastic member 122 is arranged on one side of one moving contact portion 120. The elastic member 122 provides a clamping force for the clamping clearance 1201. By changing the applied torque, the pressure for the clamping clearance 1201 can be adjusted, so that the clamping clearance 1201 has a stable clamping force, so as to ensure the fit stability between the moving contact portions 120 and the stationary contact portions 21.

[0068] Preferably, the elastic member 122 is sleeved outside each of the two moving contact pieces 121, so that the elastic members 122 and the moving contact pieces 121 form a stable clamping relationship, which is convenient for disassembly and assembly and also can ensure that the clamping clearance 1201 is provided with a stable clamping force. Further, as shown in FIG. 21, the elastic member 122 sleeved outside each of the two moving contact pieces 121 is provided with an elastic opening 1222. In this case, the elastic member 122 has a U-shaped structure as a whole, and a clearance between the elastic openings 1222 is less than or equal to the clamping clearance 1201. When the stationary contact portion 21 is plugged into the clamping clearance 1201, the elastic opening 1222 is enlarged and the elastic member 122 undergoes elastic deformation. The elastic member 122 provides a reverse pressure to the moving contact piece 121 to ensure the contact pressure between the moving contact portion 120 and the stationary contact portion 21, that is, to ensure the contact resistance and also reliable contact. Of course, the elastic member 122 may also be of a closed annular structure, such as an "o" structure formed by a rubber part, or a "□" shape formed by bending a spring steel wire or a reed.

[0069] Further, the moving contact piece 121 is also provided with a limiting groove 1211 for limiting the elastic member 122, and a central axis of the limiting groove 1211 is perpendicular to a central axis of the moving contact piece 121 to prevent the elastic member 122 from shifting during the deformation process. Preferably, the limiting grooves 1211 are formed in both sides of the moving contact piece 121 to avoid too many structures on the moving contact piece 121, which is not conducive to ensuring the stability. Preferably, a plurality of the limiting grooves 1211 are provided, and at least one spare limiting groove is reserved among the plurality of the limiting grooves 1211, such that the elastic member 122 has a plurality of assembling positions that can be adjusted. By changing a position of the elastic member 122 where a force value is applied to change a force arm for deformation of the moving contact bridge, the clamping force exerted by the elastic member on the moving contact bridge is adjusted, which is conducive to adjusting the additional clamping force provided by the elastic member 122 for the clamping clearance.

[0070] An embodiment of a moving contact bridge 12 is provided in conjunction with FIGS. 11, 12, and 17-21.

[0071] As shown in FIGS. 12 and 17, the moving contact bridge 12 includes two moving contact pieces 121, two elastic members 122, and a supporting member 123. The two moving contact pieces 121 are parallel and spaced oppositely. The center positions of the two moving contact pieces 121 are connected together through the supporting member 123. Moving contact portions 120 are cooperatively formed at the same ends of the two moving contact pieces 121, with a clamping clearance 1201 between the moving contact portions. The elastic member 122 is arranged between each moving contact portion 120 and the supporting member 123. The elastic member 122 provides additional clamping force to the clamping clearance 1201. In this embodiment, the elastic member 122 is preferably of a U-shaped structure. Of course, the elastic member 122 may also be of an annular structure sleeved outside the two moving contact pieces 121. In addition, more than one elastic member 122 may also be arranged between each moving contact portion 120 and the supporting member 123 according to actual needs.

[0072] As shown in FIGS. 17-21, the moving contact piece 121 in this embodiment includes a contact piece body. The contact piece body is a strip-shaped platy conductor. A positioning hole 1212 is formed in the middle of the contact piece body. Both end edges of the contact piece body extend outward to form a guide piece 1210. Two guide pieces 1210 of each contact piece body form a rotationally symmetrical structure with respect to the positioning hole 1212. In FIGS. 17-19, the two guide pieces 1210 of the same contact piece body extend in opposite directions respectively, and the same ends of the two moving contacts 121 are spaced oppositely to form the moving contact portion 120. At this time, a part of a clearance between the two moving contact pieces 121, which corresponds to the moving contact portion 120, is the clamping clearance 1201. Two guide pieces 1210 which are spaced oppositely are arranged on the same side of the same moving contact portion 120. The guide pieces 1210 provide a guiding role for the stationary contact assembly 2. The stationary contact portion 21 of the stationary contact assembly 2 enters the clamping clearance 1201 from the guide pieces 1210. A clamping groove 1211 is formed in the contact piece body between each guide piece 1210 and the positioning hole 1212. Preferably, the number of limiting grooves 1211 is greater than or equal to the number of elastic members 122, and the excess limiting grooves 1211 are used as spare limiting grooves to facilitate the adjustment of the assembly positions of the elastic members 122, thereby adjusting the clamping force of the elastic members 122. Of course, when the number of limiting grooves 1211 is equal to the number of elastic members 122, their assembly positions cannot be adjusted. In FIGS. 19 and 20, a pair of limiting grooves 1211 are formed in both side edges of the contact piece body between each guide piece 1210 and the positioning hole 1212, two pairs of limiting grooves 1211 of the same contact piece body form a rotationally symmetrical structure with respect to the positioning hole 1212, and the central axis of each limiting groove 1211 is perpendicular to the central axis of the contact piece body.

[0073] As shown in FIGS. 17 and 21, the elastic member 122 in this embodiment is of a U-shaped structure equipped with an elastic opening 1222. Specifically, the elastic member 122 includes two elastic arms 1221 which are spaced oppositely. One ends of the two elastic arms 1221 are bent in opposite directions and connected together to form an integrated structure and clamped into the limiting grooves 1211 on one side edge of the contact piece body, while the other ends of the two elastic arms 1221 are bent in opposite directions and are spaced oppositely to form the elastic opening 1222. A clearance between the elastic openings 1222 is less than or equal to a spacing between the two moving contact pieces 121, and the tail ends of the two elastic arms 1221 which form the elastic opening 1222 are correspondingly clamped into the limiting groove 1211 in the other side edge of the contact piece body, respectively. In this embodiment, the elastic arms 1221 of the elastic member 122 are perpendicular to the central axis of the contact piece body, and the elastic opening 1222 and the guide piece 1210 are located on the same side of the moving contact bridge 12. When the stationary contact portion 21 enters into the clamping clearance 1201, the stationary contact portion 21 may correspondingly enlarge the elastic opening 1222, so that the elastic member 122 undergoes elastic deformation. The degree of freedom of the two moving contact pieces 121 can be adaptively adjusted, and the risk of poor collision-induced closing caused by non-centering of the moving contact portion 120 and the stationary contact portion 21 due to manufacturing errors of the parts is reduced.

[0074] As shown in FIG. 17, the supporting member 123 includes a body 13. In FIG. 17, the body 13 is cylindrical. Camshaft 1232 are arranged at both opposite ends of the body 13 in a protruding manner. Each camshaft 1232 is correspondingly plugged into the positioning hole 1212 of one moving contact piece 121. A spacing between the two moving contact pieces 121, i.e., the clamping clearance 1201 of each moving contact portion 120, is limited by an axial height of the body 13.

[0075] The stationary contact assembly 2 which cooperates with the moving contact assembly 1 may adopt the prior art. In this embodiment, preferably, as shown in FIGS. 5-7, the stationary contact assembly 2 includes electric conduction plates, and each electric conduction plate correspondingly passes through one assembling groove 31. When the housing 3 is spliced by two plate bodies 301, each electric conduction plate is preferably clamped under the action of two plate bodies 301. A stationary contact portion 21 is arranged at one end of the electric conduction plate, and the stationary contact portion 21 extends into the accommodating cavity and used to cooperate with the moving contact portion 120. The two stationary contact portions 21 are spaced within the accommodating cavity and form a rotationally symmetrical structure with respect to the axis of the rotating shaft 11 (communicating hole 33). A wiring portion 22 is arranged at the other end of the electric conduction plate. Each wiring portion 22 is located outside the housing 3 for connection with a wiring assembly. When the moving contact assembly 1 in this embodiment cooperates with the stationary contact assembly 2, the elastic opening 1222 of the elastic member 122 preferably faces the stationary contact portion 21.

[0076] It should be noted that when the moving contact assembly 1 and the stationary contact assembly 2 are arranged in the housing 3, the transmission shaft 114 and the rotating portion 113 of the rotating shaft rotate to pass through one communicating hole 33 of the housing 3, respectively; and the two moving contact pieces 121 of the moving contact bridge 12 are spaced oppositely between a pair of supporting walls 302 of the housing 3.

[0077] As shown in FIGS. 1 and 23-26, each arc extinguishing system is cooperatively arranged on a side of the contact mechanism a, and used to extinguish an electric arc generated when the contact mechanism a is opened. The arc inlet 401 of the arc extinguishing system corresponds to the contact mechanism a. Each arc extinguishing system includes an arc extinguishing cover 42 and two grid groups 41 which are spaced. The arc inlet 401 which is joined with the contact mechanism a is formed in one end of the arc extinguishing cover 42. Each grid group 41 is arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41.

[0078] In this embodiment, one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited. In this way, when the electric arc current is expected to form a loop, it must break through all the arc extinguishing grids 411 in each grid group 41. The current is jointly limited by the two grid groups 41, so that the arc extinguishing grids 411 can be fully utilized, thereby improving the arc extinguishing ability of the arc extinguishing systems.

[0079] Further, the arc extinguishing system also includes a short-circuiting plate 44 (see FIGS. 25 and 26) or a connecting grid group 41. The short-circuiting plate 44 or the connecting grid group 41 is arranged in the arc running channel 402, so that one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the short-circuiting plate 44 or the connecting grid group 41. The short-circuiting plate 44 is small in size, and suitable for contact units with small internal spaces. The connecting grid group 41 occupies more space, but at the same time has an effect of cutting the electric arc and achieves a better arc extinguishing effect. In addition, it is also applicable for equipotential short-circuiting by directly connecting tail grids in the two grid groups away from one end of the arc inlet 401, without providing the short-circuiting plate 44 or the connecting grid group.

[0080] Further, as shown in FIGS. 23 and 24, each arc extinguishing system further includes at least two magnetic conduction plates 43. The arc running channel 402 is located between the at least two magnetic conduction plates 43. A magnetic field is formed by the magnetic conduction plates 43 in the arc running channel 402. In this way, two grid groups 41 are arranged in the relatively closed arc extinguishing cover 42. The arc running channel 402 between the two grid groups 41 is correspondingly located between the magnetic conductive plates 43. The magnetic conduction plates 43 form a magnetic field within the arc running channel 402, which facilitates blowing the electric arc toward the grid groups 41. The relatively closed arc extinguishing cover 42 can extend the cooperation time of the electric arc and the grid groups 41, thereby improving an arc extinguishing effect.

[0081] Further, each magnetic conduction plate 43 is attached to the side wall of the arc extinguishing cover 42 along one side of the arc running channel 402, and the width of each magnetic conduction plate 43 is approximately equal to a spacing between the two grid groups 41. Preferably, the width of each magnetic conduction plate 43 is equal to the spacing between the two grid groups 41. The magnetic conduction plates 43 may be embedded into the side wall of the arc extinguishing cover 42, or may be attached to the inner or outer surface of the side wall of the arc extinguishing cover 42. The magnetic conduction plates 43 with smaller sizes are conducive to reducing the cost. Of course, in a case where the size of each magnetic conduction plate 43 is relatively large, the magnetic conduction plate 43 is preferably arranged on the outer surface of the side wall of the arc extinguishing cover 42.

[0082] In addition, the two grid groups 41 may be assembled together in one arc extinguishing cover 42 to form an arc extinguishing chamber 40, or the two grid groups 41 are correspondingly assembled in the two arc extinguishing covers 42 respectively to form two independent arc extinguishing chambers 40, which can meet different product needs.

[0083] A first embodiment of an arc extinguishing system is provided in conjunction with FIGS. 1, and 23-31.

[0084] As shown in FIGS. 23-31, the arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41, a short-circuiting plate 44, and a pair of magnetic conduction plates 43. An arc inlet 401 is formed in one end of the arc extinguishing cover 42 and used to introduce the electric arc into the arc extinguishing system in cooperation with the contact mechanism a. The two grid groups 41 are spaced oppositely and arranged on one side of the arc inlet 401. A spacing between the two grid groups 41, which is used as the arc running channel 402, is communicated with the arc inlet 401. The short-circuiting plate 44 is arranged at an end of the arc running channel 402 away from the arc inlet 401. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially connected through the short-circuiting plate 44. A pair of magnetic conduction plates 43 are spaced, and the arc running channel 402 is located between the pair of magnetic conduction plates 43. After the pair of magnetic conduction plates 43 are magnetized, a magnetic field is correspondingly generated within the arc running channel 402. Specifically, each magnetic conduction plate 43 is arranged on a side wall of the arc extinguishing cover 42 corresponding to the arc running channel 402, and the magnetic conduction plate 43 may be optionally embedded into the side wall of the arc extinguishing cover 42. Preferably, the magnetic conduction plates 43 are attached to an outer side wall of the arc extinguishing cover 42 for easy disassembly and assembly.

[0085] As shown in FIGS. 25-28, the arc extinguishing cover 42 includes two cover bodies 421 which are spaced oppositely. The two cover bodies 421 are encircled to form a hollow cavity with two open ends. In drawings, the arc extinguishing cover 42 is in a "□"-shape as a whole. In this case, an arc extinguishing cavity with two open ends is formed inside the arc extinguishing cover 42. One open end of the arc extinguishing cavity is used as the arc inlet 401, and the other open end opposite the arc inlet 401 is closed by the shell 5, preferably assembled in the shell 5 and closed by the inner side wall of the housing 5. Of course, the other open end of the arc extinguishing cover 42 is closed by a partition plate arranged in the shell 5. Therefore, the arc extinguishing cavity forms a relatively closed cavity body, and the side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401 is provided with a plurality of exhaust holes 423, and the plurality of exhaust holes 423 are spaced along a direction away from the arc inlet 401.

[0086] As shown in FIGS. 25, 26 and 29, two grid groups 41 are arranged in the arc extinguishing cover 42. Each grid group 41 includes a plurality of arc extinguishing grids 411 which are spaced. An arc extinguishing clearance is formed between every two adjacent arc extinguishing grids 411. At least part of the arc extinguishing clearance is correspondingly communicated with the exhaust holes 423. An arc extinguishing notch 412 is formed in one end of each arc extinguishing grid 411. The arc extinguishing notches 412 of the same grid group 41 are communicated to form an arc extinguishing groove 410. The arc extinguishing groove 410 faces the arc running channel 402. One end of the arc extinguishing groove 410 is communicated with the arc inlet 401. The arc extinguishing grooves 410 of the two grid groups 41 are spaced oppositely. In this embodiment, each arc extinguishing notch 412 extends away from the opening direction along a direction deviating from the axis, such that the entire arc extinguishing notch 412 is in a "y" shape. The extensions 304 of the two adjacent arc extinguishing notches 412 are misaligned against each other, which is conducive to improving the cutting of the electric arc by the arc extinguishing grids 411. Of course, each grid group 41 may adopt the prior art.

[0087] Two mounting areas are provided in the arc extinguishing cavity. The two mounting areas are spaced oppositely, and each mounting area is correspondingly equipped with a grid group 41. Preferably, each mounting area includes a plurality of grid slots 424 which are spaced. The grid slots 424 and the exhaust holes 423 are located in adjacent side walls of the arc extinguishing cover 422, respectively. An arc extinguishing grid 411 is correspondingly plugged into each grid slot 424.

[0088] In this embodiment, as shown in FIGS. 23-28, docking portions 422 are arranged on both side edges of each cover body 421. The cover body 421 provided with the docking portion 422 is in a "" shape as a whole. A plurality of grid slots 424 which are spaced are formed in the middle of the same cover body 421. The docking portions 422 on the same side of the two cover bodies 421 cooperate with each other to form side walls of the arc extinguishing cover 32 where the exhaust holes 423 are formed. In FIGS. 23-28, a plurality of opening grooves, which are used as the exhaust holes 423, are spaced on the edge of each docking portion 422, and the plurality of exhaust holes 423 are arranged equidistantly. When the docking portions 422 of the two cover bodies 421 are docked, the exhaust holes 423 of the two docking portions 422 located on the same side are misaligned against each other, so that electric arcs and electric arc particles can be prevented from being short-circuited outside the arc extinguishing cover 42. Of course, the exhaust holes 423 formed in each docking portion 422 may also be through holes 1121.

[0089] Of course, the docking portions 422 are formed in both side edges of one cover body 421 which is in a "" shape as a whole, while the other cover body 421 which is not provided with the docking portion 422 is in a "-" shape as a whole. Alternatively, the cover bodies may be encircled to form the arc extinguishing cover 42 which is open at both ends. In this case, the exhaust holes 423 are formed in the middle of each docking portion 422, and every two adjacent exhaust holes 423 are misaligned against each other. Alternatively, the docking portion 422 is formed on a single side of each cover body 421, such that each cover body 421 is in a "" shape as a whole. The docking portion 422 of each cover body 421 is provided with a plurality of exhaust holes 423.

[0090] As shown in FIGS. 25, 26 and 30, the short-circuiting plate 44 is located at an end of the arc running channel 402 away from the arc inlet 401. Two pins 441 of the short-circuiting plate 44 are respectively adjacent to one ends of the two grid groups 41 away from the arc inlet 401, so that an electric clearance between the two grid groups 41 away from the arc inlet 401 is less than a minimum physical spacing between the two grid groups 41. That is, a distance between one end of each gate group 41 way from the arc inlet 401 and one pin 441 is less than the minimum physical spacing between the two gate groups 41, so that an electric arc current forms a loop and needs to flow through the short-circuiting plate 44, thereby achieving equipotential short-circuiting of one ends of the two gate groups 41 away from the arc inlet 401. Further, the short-circuiting plate 44 also includes an arc striking plate 442. The arc striking plate 422 is connected to the two pins 441 and extends along a center line of the arc running channel 402 in a direction close to the arc inlet 401. The arc striking plate 442 is used to bridge an electric arc.

[0091] As shown in FIGS. 25, 26 and 30, the short-circuiting plate 44 includes two arc striking pieces. One ends of the two arc striking pieces are attached to form the arc striking plate 422. A notch is formed in an end portion of the arc striking plate 442. This notch is located between two grid groups 41 to play a communicating role. The middle parts of the two arc striking pieces are deflected toward both sides respectively to form deflected segments. The end portion of each deflected segment is bent to form one pin 441, so that the short-connecting plate 44 is in a "herringbone" shape as a whole. Each pin 441 is spaced opposite to the corresponding arc extinguishing grid 411 in one grid group 41 away from the arc inlet 401, and a clearance between the pin 441 and the arc extinguishing grid 411 is much less than the spacing between the two grid groups 41. In drawings, each pin 441 is spaced opposite to the arc extinguishing notch 412 of the arc extinguishing grid 411 in the grid group 41 away from the arc inlet 401.

[0092] Further, as shown in FIGS. 25, 26 and 28, short-circuiting plate mounting portions are arranged in the arc extinguishing cover 42. The short-circuiting plate 44 is assembled in the arc running channel 402 by the short-circuiting plate mounting portion in a limiting manner. The short-circuiting plate mounting portions are formed in the middle of at least one cover body 421. The short-circuiting plate mounting portions and the exhaust holes 423 are arranged on two adjacent side walls of the arc extinguishing cover 42, respectively. Preferably, the short-circuiting plate mounting portion is arranged in the middle of each of the two cover bodies 421. When the two cover bodies 421 are encircled to form the arc extinguishing cover 42, the short-circuiting plate mounting portions are used to limit the short-circuiting plate 44. As shown in FIG. 28, the short-circuiting plate mounting portion includes a first boss 4261 and a second boss 4262 which are spaced. The first boss 4261 is located at an end of the arc running channel 402 close to the arc inlet 401, while the second boss 4262 is located at an end of the arc running channel 402 away from the arc inlet 401. The short-circuiting plate 44 is assembled between the first boss 4261 and the second boss 4262 in a limiting manner. In drawings, a notch is formed in a side of the first boss 4261 facing the second boss 4262. This notch is engaged with the arc striking plate 442 of the short-circuiting plate 44. The second boss 4262 is in a triangular shape as a whole, which is used to separate and limit the two pins 441 of the short-circuiting plate 44, so that the two pins 441 of the short-circuiting plate 44 extend toward the two grid groups 41, respectively. Of course, the short-circuiting plate 44 may also be fitted to the arc extinguishing cover 42 in other ways.

[0093] In addition, a pair of magnetic conduction plates 43 are spaced oppositely, and the arc running channel 402 is located between the pair of magnetic conduction plates 43, such that a magnetic field is formed in the arc running channel 402 after the pair of magnetic conduction plates 43 are magnetized. The magnetic field direction is perpendicular to a connecting line direction between the two grid groups 41 to accelerate the introduction of the electric arc into the two grid groups 41.

[0094] As shown in FIGS. 23, 24 and 27, a magnetic conduction plate mounting portion is arranged in the middle of each cover body 421. Preferably, the magnetic conduction plate mounting portion is located outside the arc extinguishing cavity. In this embodiment, the magnetic conduction plate mounting portion is located on the outer surface of the cover body 421, that is, arranged on each of the outer surfaces of the two cover bodies 421. Specifically, the magnetic conduction plate mounting portion includes a magnetic conduction plate mounting groove 4251 and a fastening boss 4252 arranged in the magnetic conduction plate mounting groove 4251. In FIG. 27, the magnetic conduction plate mounting groove 4251 is formed in the outer surface of the cover body 421, and each magnetic conduction plate mounting groove 4251 corresponds to the arc running channel 402. At least one fastening boss 4252 is arranged at the bottom of the magnetic conduction plate mounting groove 4251 in a protruding manner, and the fastening boss 4252 is correspondingly plugged into the fastening groove 431 of the magnetic conduction plate 43. In FIGS. 23, 24 and 31, the magnetic conduction plate 43 is of a rectangular platy structure, and two fastening grooves 431 are formed in the middle of the magnetic conduction plate 43. Of course, it is also possible to not provide the fastening boss 4252, and the magnetic conduction plate 43 is directly embedded or adhered into the magnetic conduction plate mounting groove 4251.

[0095] In addition, the arc extinguishing cover 42 may also be provided with a limited assembly structure, so that the arc extinguishing cover 42 is stably assembled in the shell 5 of the contact unit. In FIGS. 23, 24, 27 and 28, an engagement groove 427 is formed in an edge of the arc extinguishing cover 42 away from the arc inlet 401. When the arc extinguishing cover 42 is assembled in the shell 5 of the isolation switch, the engagement groove 427 may be engaged with an engagement portion (not shown) in the shell 5 to achieve stable assembly. Of course, it is also possible to assemble directly through fasteners such as screws without providing a limited assembly structure.

[0096] A second embodiment (not shown) of an arc extinguishing system is provided.

[0097] The arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41 and a pair of magnetic conduction plates 43. The structures of the arc extinguishing cover 42, the grid groups 41 and the magnetic conduction plates 43 are the same as those of the first embodiment, but different from the first embodiment in that: the arc extinguishing system in this embodiment is no longer provided with a short-circuiting plate 44, but a connecting grid group is arranged between the two grid groups 41; the connecting grid group is arranged at an end of the arc running channel 402 away from the arc inlet 401; and both ends of the connecting grid group are spaced opposite to one end of each grid group 41 away from the arc inlet 401, so that an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401 is less than a minimum physical spacing between the two grid groups 41, that is, a distance between one end of each grid group 41 away from the arc inlet 401 and one end of the connecting grid group, i.e., an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401, is less than the minimum physical spacing between the two grid groups 41.

[0098] Specifically, the connecting grid group includes a plurality of connecting grids which are spaced. The connecting grids close to the grid group 41 are spaced opposite to the arc extinguishing grids 411 in the grid group 41 away from one end of the arc inlet 401. Therefore, one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this embodiment, the structure of the connecting grids is preferably the same as the arc extinguishing grids 411 in the grid group 41. Correspondingly, an arc extinguishing notch 412 is also formed in one end of each connecting grid. The arc extinguishing notches 412 of the connecting grid group 41 are communicated, and are communicated with the arc extinguishing grooves 410 of the two grid groups 41, respectively.

[0099] In this embodiment, the connecting grid group is arranged along a straight line connected between the two grid groups 41. Therefore, the two grid groups 41 and the connecting grid group form a "U"-shaped structure in the arc extinguishing cover 42. Of course, the connecting grid group may also be arranged along an arc line connected between the two grid groups 41. Preferably, a concave surface of the arc line faces the arc inlet 401. Therefore, the two grid groups 41 and the connecting grid group 41 also form a "U"-shaped structure in the arc extinguishing cover 42. Alternatively, the connecting grid group 41 may also be arranged along a fold line connected between the two grid groups 41, for example, along an inverted "V"-shaped fold line. Preferably, a spacing between the two grid groups 41 away from the arc inlet 401 gradually decreases. Therefore, the two grid groups 41 and the connecting grid group 41 form a "W"-shaped structure in the arc extinguishing cover 42.

[0100] A third embodiment (not shown) of an arc extinguishing system is provided.

[0101] In this embodiment, the arc extinguishing system includes an arc extinguishing cover 42 which is the same as that in the first embodiment. Two grid groups which are the same as those in the first embodiment are arranged in the arc extinguishing cover 42. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41. The arrangement mode of the arc extinguishing grids 411 in each grid group 41 may refer to the first embodiment. The third embodiment is different from the first embodiment in that: no short-circuiting plate 44 is arranged between the two grid groups 41, one arc extinguishing grid 411 in each grid group 41 away from the arc inlet 401 is used as a tail grid, and the tail grids in the two grid groups 41 are connected to achieve equipotential short-circuiting.

[0102] Preferably, one end of each tail grid close to the arc running channel 402 is bent toward the arc inlet 401. Therefore, when the two tail grids are connected to form an arc striking portion which protrudes toward the arc inlet 401, the arc striking portion is of a V-shaped structure for bridging the electric arc.

[0103] A fourth embodiment (not shown) of an arc extinguishing system is provided.

[0104] The arc extinguishing system includes two arc extinguishing covers 42 and two grid groups 41. Each grid group 41 adopts the grid group 41 in the first embodiment. The two grid groups 41 are arranged in the two arc extinguishing covers 42, respectively. Openings are formed in opposite sides of the two arc extinguishing covers 42, respectively. The arc extinguishing groove 410 of each grid group 41 is opposite to the opening. An arc running channel 402 is formed between the two arc extinguishing grooves 410. The two arc extinguishing chambers 40 are intercommunicated through the arc running channel 402 and the openings of the two arc extinguishing covers 42. The two arc extinguishing chambers 40 are intercommunicated through the arc running channel 402 and the openings of the two arc extinguishing covers 42. In this case, the arc running channel 402 is not completely located in the same arc extinguishing cover 42. It should be noted that the opening of each arc extinguishing cover 42 may cooperate with a partition plate in the contact unit or an additional connecting plate, such that the arc extinguishing covers 42 form a "□"-shaped structure. However, an opening is formed in a side of the arc extinguishing cover 42. A side wall of the arc extinguishing cover 42 facing the opening is also provided with a plurality of exhaust holes 423, and every two adjacent exhaust holes 423 are also misaligned against each other.

[0105] A short-circuiting plate 44 which is the same as that in the first embodiment is also arranged in the arc running channel 402. One ends of the two grid groups 41 away from the air inlet 401 are equipotentially short-circuited through the short-circuiting plate 44. In this case, the arc extinguishing system includes two arc extinguishing chambers 40. The short-circuiting plate 44 is arranged between the openings of the two arc extinguishing covers 42. The short-circuiting plate 44 may have the same structure as that in the first embodiment. Two pins 441 of the short-circuiting plate 44 preferably pass through each opening, so that each pin 441 is spaced opposite to one end of one grid group 41 away from the arc inlet 401. The arc striking plate 442 of the short-circuiting plate 44 is located between the two openings, and the notch in the arc striking plate 442 may communicate the two arc extinguishing covers 42.

[0106] Alternatively, the arc running channel 402 is also provided with a connecting arc extinguishing chamber. A connecting grid group which is the same as that in the second embodiment is arranged in the connecting arc extinguishing chamber. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this case, the arc extinguishing system includes two arc extinguishing chambers 40 and a connecting arc extinguishing chamber.

[0107] Of course, two arc extinguishing covers 42 may also be adopted in the third embodiment. In this case, one end of at least one tail grid may pass through the opening of the arc extinguishing cover 42, thereby forming an arc striking portion in the arc running channel 402.

[0108] In this embodiment, the arc extinguishing system further includes a pair of magnetic conduction plates 43, wherein the magnetic conduction plates 43 are arranged outside the two arc extinguishing covers 42, and a projection of the magnetic conduction plates 43 covers the arc running channel 402. Each magnetic conduction plate 43 may also of a rectangular structure. Preferably, magnetic conduction plate mounting grooves 4251 are formed in outer side walls of the two arc extinguishing covers 42, respectively. A fastening boss 4252 is arranged at the bottom of each magnetic conduction plate mounting groove 4251. The fastening boss 4252 is in limiting fit with the fastening groove 431 of the magnetic conduction plate 43, and its specific position is adjusted according to actual needs. Of course, the magnetic conduction plates 43 and the arc extinguishing cover 42 may also be cooperated in other ways.

[0109] As shown in FIGS. 32 and 33, a length direction of the shell 5 is taken as the first direction, a width direction of the shell 5 is taken as the second direction, a thickness direction of the shell 5 is taken as the third direction, and the first, second and third directions are perpendicular to each other.

[0110] In the embodiment of the above arc extinguishing system, as shown in FIGS. 1-5, 32 and 33, each arc extinguishing system further includes two buffer areas 45. In the second direction, the two buffer areas 45 are located on both sides of the arc extinguishing cover 42, and each buffer area 45 is opposite to the exhaust holes 423 of the arc extinguishing cover 42. A plurality of upright columns 451 opposite to the exhaust holes 423 are arranged in the buffer areas 45 in the third direction. High-temperature exhaust gas discharged from the exhaust holes 423 is buffered by the plurality of upright columns 451 and does not need to be discharged from the shell 5. It is unnecessary to form an additional exhaust port in the shell 5 to avoid the discharge of the high-temperature gas from affecting its safety in use.

[0111] Preferably, the plurality of upright columns 451 are arranged in two rows. The plurality of upright columns 451 in each row are arranged equidistantly along the first direction. The upright columns 451 in the adjacent two rows are misaligned against each other, such that a buffering effect can be further improved within a limited space, which is conducive to reducing the area of the buffer areas 45. Further, baffles 52 are also arranged around the arc extinguishing chamber 40. The baffles 52 are spaced opposite to the exhaust holes 423 of the arc extinguishing chamber 40, so that the space of the shell 5 between the baffles 52 and the exhaust holes 423 forms the buffer area 45. The baffles 52 and the upright columns 451 are arranged together on the bottom wall of the shell 5 in a protruding manner. Preferably, a protruding height of the baffles 52 is greater than a protruding height of the upright columns 451, so as to avoid the high-temperature exhaust gas from overflowing from the buffer areas 45 to a gas space in the shell 5, so that the upright columns 451 are fully utilized, thereby reducing the impact on other components in the shell 5.

[0112] It should be explained that, in the description of the present invention, the terms such as "up", "down", "left", "right", "inner" and "outer" indicating the directional or positional relations on the basis of the directional or positional relations shown in the drawings are only used for conveniently describing the present invention and simplifying the description, not indicate or imply that the referred devices or elements must have a specific orientation and be configured and operated in a specific direction; therefore, they cannot be construed as a limitation on the present invention.

[0113] We have made further detailed description of the present invention mentioned above in combination with specific preferred embodiments, but it is not deemed that the specific embodiments of the present invention is only limited to these descriptions. A person skilled in the art can also, without departing from the concept of the present invention, make several simple deductions or substitutions, which all be deemed to fall within the protection scope of the present invention.

Examples

first embodiment

[0083]an arc extinguishing system is provided in conjunction with FIGS. 1, and 23-31.

[0084]As shown in FIGS. 23-31, the arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41, a short-circuiting plate 44, and a pair of magnetic conduction plates 43. An arc inlet 401 is formed in one end of the arc extinguishing cover 42 and used to introduce the electric arc into the arc extinguishing system in cooperation with the contact mechanism a. The two grid groups 41 are spaced oppositely and arranged on one side of the arc inlet 401. A spacing between the two grid groups 41, which is used as the arc running channel 402, is communicated with the arc inlet 401. The short-circuiting plate 44 is arranged at an end of the arc running channel 402 away from the arc inlet 401. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially connected through the short-circuiting plate 44. A pair of magnetic conduction plates 43 are spaced, and the arc ...

second embodiment

[0106]Alternatively, the arc running channel 402 is also provided with a connecting arc extinguishing chamber. A connecting grid group which is the same as that in the second embodiment is arranged in the connecting arc extinguishing chamber. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this case, the arc extinguishing system includes two arc extinguishing chambers 40 and a connecting arc extinguishing chamber.

third embodiment

[0107]Of course, two arc extinguishing covers 42 may also be adopted in the In this case, one end of at least one tail grid may pass through the opening of the arc extinguishing cover 42, thereby forming an arc striking portion in the arc running channel 402.

[0108]In this embodiment, the arc extinguishing system further includes a pair of magnetic conduction plates 43, wherein the magnetic conduction plates 43 are arranged outside the two arc extinguishing covers 42, and a projection of the magnetic conduction plates 43 covers the arc running channel 402. Each magnetic conduction plate 43 may also of a rectangular structure. Preferably, magnetic conduction plate mounting grooves 4251 are formed in outer side walls of the two arc extinguishing covers 42, respectively. A fastening boss 4252 is arranged at the bottom of each magnetic conduction plate mounting groove 4251. The fastening boss 4252 is in limiting fit with the fastening groove 431 of the magnetic conduction plate 43, and ...

[0001] The present application claims priority to Chinese Patent Application No. 202310761027.1 filed on June 26, 2023, and Chinese Patent Application No. 202310761480.2 filed on June 26, 2023, both of which are incorporated herein in their entireties by reference.Technical Field

[0002] The present invention relates to the field of switching electrical appliances, in particular to a contact unit and a rotary isolation switch.Background

[0003] With the rapid development of Alternating Current (AC) and Direct Current (DC) electrical appliance industry, rotary isolation switches have been widely used. The isolation switch is a switching device that has both an isolation function and a switching function. The traditional rotary isolation switch is generally provided with an operating module and a contact module driven by the operating module, wherein the contact module includes a plurality of contact units which are laminated, and each contact unit is generally provided with a contact mechanism and an arc extinguishing system. The existing contact unit generally has the following defects: firstly, there are many contact mechanism components, resulting in inconvenience of assembly; secondly, the arc extinguishing system is limited by space, resulting in poor arc extinguishing effect; thirdly, the cooperation between the contact mechanism and the arc extinguishing system is more complicated, resulting in poor arc striking effect; and fourthly, the internal layout of the contact unit is complicated, and especially, the contact mechanism and the arc extinguishing system do not have a modular structure, making the assembly cumbersome and unable to meet the modular development of the isolation switch.Summary

[0004] An object of the present invention is to overcome at least one defect of the prior art and provide a contact unit and a rotary isolation switch, which have simple structure and high reliability.

[0005] In order to achieve the above objective, the present invention provides the following technical solution:

[0006] The present invention provides a contact unit, comprising a shell and a contact mechanism arranged in the shell, in which the contact mechanism comprises a pair of static contact assemblies and a moving contact assembly; each stationary contact assembly comprises a stationary contact portion; arc extinguishing systems are arranged on both sides of the contact mechanism; each arc extinguishing system comprises an arc extinguishing cover; one end of the arc extinguishing cover is used as an arc inlet; and

[0007] the contact mechanism further comprises a housing; an accommodating cavity of the housing is provided with two opposing openings; each opening is connected to one arc inlet; the moving contact assembly and the stationary contact portions are assembled in the accommodating cavity; the moving contact assembly is located between a pair of stationary contact portions; and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space.

[0008] Preferably, the arc extinguishing cover is open at both ends, one open end is used as the arc inlet, and the other open end is abutted against and closed by the shell; or the arc extinguishing cover is open at one end and closed at the other end, and the open end is used as the arc inlet.

[0009] Preferably, the moving contact assembly comprises a rotating shaft and a moving contact bridge arranged along a radial direction of the rotating shaft; the rotating shaft rotates between a pair of stationary contact portions; both ends of the moving contact bridge are used as moving contact portions which cooperate with the stationary contact portions; and the moving contact assembly cooperates with the accommodating cavity to block two openings from being communicated with each other.

[0010] Preferably, a circumferential side wall of the rotating shaft is provided with two opening limiting portions in a protruding manner; two opening barrier portions are arranged in the accommodating cavity; the opening barrier portions are located on a rotation trajectory of the opening limiting portions; each opening limiting portion is adjacent to one moving contact portion; when the rotating shaft rotates to an opening position, the opening limiting portions are in limiting fit with the opening barrier portions; and the rotating shaft, the two opening limiting portions and the two opening barrier portions block two openings from being communicated with each other.

[0011] Preferably, one stationary contact portion and one opening barrier portion are located on both sides of the same opening of the housing; one moving contact portion and one opening limiting portion jointly rotate between one stationary contact portion and one opening barrier portion; and the opening limiting portion is located on a side of the moving contact portion away from the stationary contact portion.

[0012] Preferably, the housing is of an integrated structure; alternatively, the housing comprises two plate bodies which are spaced oppositely; the two plate bodies are encircled to form a hollow cavity body which is open at both ends; a hollow part of the hollow cavity body is used as the accommodating cavity; splicing structures which cooperate with each other are arranged between the two plate bodies; and the splicing structures enable the two plate bodies to form an integral body that can be split in a pluggable manner.

[0013] Preferably, the housing comprises two plate bodies which are spaced oppositely; extensions are arranged on the edges of both sides of each plate body; the extensions on the same sides of the two plate bodies cooperate with each other to form connecting walls of the housing; each connecting wall is provided with an assembling groove and one opening barrier portion; and the middle parts of the two plate bodies are used as a pair of supporting walls.

[0014] Preferably, the arc extinguishing system further comprises a buffer area; the arc extinguishing cover is open at both ends; one open end of the arc extinguishing cover is used as the arc inlet; a side wall of the arc extinguishing cover adjacent to the arc inlet is provided with a plurality of exhaust holes; the arc inlet is communicated with the contact mechanism in a first direction of the shell; the buffer area and the arc extinguishing cover are arranged along a second direction of the shell; the buffer area is joined with the exhaust holes; and the first direction is perpendicular to the second direction.

[0015] Preferably, each arc extinguishing system comprises two buffer areas; in the second direction, the two buffer areas are located on both sides of the arc extinguishing cover; each buffer area is provided with a plurality of upright columns, which are opposite to the exhaust holes, along a third direction; and the third direction is perpendicular to the first direction and the second direction, respectively.

[0016] Preferably, baffles are also arranged around the arc extinguishing chamber; the baffles are spaced opposite to the exhaust holes of an arc extinguishing chamber, so that a space of the housing between the baffle and the exhaust hole forms the buffer area; the plurality of upright columns are arranged in at least two rows; the plurality of upright columns in each row are arranged equidistantly in the first direction; and the upright columns in adjacent rows are misaligned against each other.

[0017] Preferably, each arc extinguishing system comprises an arc extinguishing chamber, the arc extinguishing chamber comprises an arc extinguishing cover and two grid groups which are spaced within the same arc extinguishing cover, and an arc running channel which is communicated with the arc inlet is arranged between the two grid groups; alternatively, the arc extinguishing system comprises two arc extinguishing chambers, each arc extinguishing chamber comprises an arc extinguishing cover and a grid group arranged within the arc extinguishing cover, an opening is formed in a side of each arc extinguishing cover adjacent to the arc inlet, openings of the two arc extinguishing covers are opposite each other, an arc extinguishing groove of each grid group is communicated with the arc inlet, the arc extinguishing groove of each grid group is opposite to the opening, and a spacing between the two grid groups forms the arc running channel which is communicated with the arc inlet.

[0018] Preferably, each arc extinguishing system further comprises a short-circuiting plate; the short-circuiting plate is arranged at an end of the arc running channel away from the arc inlet; the short-circuiting plate comprises two pins and an arc striking plate; the two pins extend toward one ends of the two grid groups away from the arc inlet respectively, so that an electric clearance between one ends of the two grid groups away from the arc inlet is less than a minimum physical distance between the two grid groups; and the arc striking plate extends along a center line of the arc running channel toward a direction close to the arc inlet.

[0019] Preferably, one arc extinguishing grid in each grid group away from the arc inlet is a tail grid, the tail grids in the two grid groups are connected, and the tail grids in the two grid groups protrude toward the arc inlet to form an arc striking portion for bridging electric arcs; or

[0020] a connecting grid group is arranged at an end of the arc running channel away from the arc inlet, the connecting grid group comprises a plurality of connecting grids which are spaced, and the plurality of connecting grids are arranged along a straight line, an arc line or a fold line connected between the two connecting grid groups.

[0021] Preferably, each arc extinguishing system further comprises at least two magnetic conduction plates which are spaced, each magnetic conduction plate is arranged outside the arc extinguishing cover, the arc running channel is located between the at least two magnetic conduction plates, and a magnetic field is formed by the magnetic conduction plates in the arc running channel.

[0022] The present invention further provides a rotary isolation switch, comprising an operating module and a contact module, in which the contact module comprises at least one contact unit as above-mentioned, and the at least one contact unit is driven by an operating mechanism of the operating module for opening and closing.

[0023] According to the contact unit and the rotary isolation switch of the present invention, the contact mechanism and each of the arc extinguishing systems form a modular structure, which is convenient for assembly and also meets the modular development of the isolation switch. Meanwhile, a housing of the contact mechanism is docked with an arc inlet of an arc extinguishing cover, and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space, so that an electric arc generated by the contact mechanism flows within a relatively closed space, thereby improving arc striking and arc extinguishing effects.

[0024] In addition, the cooperation between the moving contact assembly and the accommodating cavity can prevent the communication between the two openings of the housing, and the accommodating cavity is divided into two relatively independent parts, thereby avoiding the interaction between the two arc extinguishing systems through the accommodating cavity, and at the same time increasing an airtightness effect.

[0025] In particular, the cooperation between the opening limiting portions of the rotating shaft and the opening barrier portions of the housing can not only play a limiting role during opening, but also increase the air tightness and creepage distance.

[0026] In addition, the arc extinguishing systems form a relatively closed space through the arc extinguishing cover, and then equipped with two grid groups, which facilitates improving their arc extinguishing ability.

[0027] In addition, each arc extinguishing system is also provided with a short-circuiting plate, which makes an electric clearance between one ends of the two grid groups away from the arc inlet is less than a minimum physical distance between the two grid groups, thereby increasing the utilization rate of the arc extinguishing grids in the grid groups and improving the arc extinguishing effect.

[0028] In addition, each arc extinguishing system is also provided with magnetic conduction plates, and the arc running channel is provided between the magnetic condition plates, so that the magnetic conduction plates cooperate with each other in the arc running channel to form a magnetic field, which is conducive to introducing the electric arc into the grid groups and improving the arc quenching ability.

[0029] In addition, a plurality of upright columns are provided in a buffer area to cool and adsorb exhaust gas, so that the exhaust gas is cooled and absorbed in the buffer area, avoiding the exhaust gas from being discharged from the shell and improving the safety in use.Brief Description of the Drawings

[0030] FIG. 1 is a schematic structural diagram of a contact unit in the present invention; FIG. 2 is a schematic structural diagram (in a closed state) of a contact mechanism and an arc extinguishing chamber in the present invention; FIG. 3 is a schematic structural diagram (in an opened state) of the contact mechanism and the arc extinguishing chamber in the present invention; FIG. 4 is a schematic diagram of electric arc flowing when the contact mechanism is opened in the present invention; FIG. 5 is a schematic structural diagram of the contact mechanism in the present invention; FIGS. 6-7 are schematic exploded views of the contact mechanism in the present invention; FIG. 8 is a schematic structural diagram showing a side of a plate body facing an accommodating cavity in the present invention; FIG. 9 is a schematic structural diagram of a side of the plate body away from the accommodating cavity in the present invention; FIGS. 10-11 are schematic structural diagrams of a rotating shaft and a moving contact bridge in the present invention; FIG. 12 is a schematic structural diagram of the disassembled rotating shaft and the moving contact bridge in the present invention; FIG. 13 is a schematic structural diagram showing a side of a contact support facing a cover plate in the present invention; FIG. 14 is a schematic structural diagram showing a side of the contact support away from the cover plate in the present invention; FIG. 15 is a schematic structural diagram showing a side of the cover plate facing the contact support in the present invention; FIG. 16 is a schematic structural diagram showing a side of the cover plate away from the contact support in the present invention; FIG. 17 is a schematic structural diagram of the moving contact bridge in the present invention; FIG. 18 is a schematic structural diagram of a moving contact piece and an elastic member in the present invention; FIG. 19 is a schematic structural diagram of the moving contact piece in the present invention; FIG. 20 is a side view of the moving contact piece in the present invention; FIG. 21 is a schematic structural diagram of the elastic member in the present invention; FIG. 22 is a schematic structural diagram of a supporting member in the present invention; FIGS. 23-24 are schematic structural diagrams of the arc extinguishing chamber in the present invention; FIGS. 25-26 are schematic structural diagrams of a cover body, a grid group and a short-circuiting plate in the present invention; FIG. 27 is a schematic structural diagram of the cover body in the present invention; FIG. 28 is a schematic structural diagram of a grid slot formed in the cover body in the present invention; FIG. 29 is a schematic structural diagram of the grid group in the present invention; FIG. 30 is a schematic structural diagram of the short-circuiting plate in the present invention; FIG. 31 is a schematic structural diagram of a magnetic conduction plate in the present invention; FIG. 32 is a schematic structural diagram of the contact unit in the present invention; and FIG. 33 is a schematic structural diagram of a shell in the present invention.

[0031] Reference symbols represent the following components: a-contact mechanism, 1-moving contact assembly, 11-rotating shaft, 111-contact support, 1111-radial groove, 112-cover plate, 1121-through hole, 113-rotating portion, 114-transmission shaft, 115-opening limiting portion, 116-snap-fit groove, 117-transmission groove, 12-moving contact bridge, 120-moving contact portion, 1201-clamping clearance, 121-moving contact piece, 1210-guide piece, 1211-limiting groove, 1212-positioning hole, 122-elastic member, 1221-elastic arm, 1222-elastic opening, 123-supporting member, 1231-body, 1232-camshaft, 13-fastener, 2-stationary contact assembly, 21-stationary contact portion, 22-wiring portion, 3-housing, 301-plate body, 302-supporting wall, 303-connecting wall, 304-extension, 31-assembling groove, 32-opening barrier portion, 33-communicating hole, 341-first limiting portion, 342-second limiting portion, 351-buckle, 352-clamping groove, 361-positioning groove, 40-arc extinguishing chamber, 401-arc inlet, 402-arc running channel, 41-grid group, 410-arc extinguishing groove, 411-arc extinguishing grid, 412-arc extinguishing notch, 42-arc extinguishing cover, 421-cover body, 422-docking portion, 423-exhaust hole, 424-grid slot, 4251-magnetic conduction plate mounting groove, 4252-fastening boss, 4261-first boss, 4262-second boss, 427-engagement groove, 43-magnetic conduction plate, 431-fastening groove, 44-short-circuiting plate, 441-pin, 442-arc striking plate, 45-buffer area, 451-upright column, 5-shell, 511-first matching portion, 512-second matching portion, 52-baffle, 521-straight segment, 522-joining segment, 53-limiting plate, 531-notch, 54-central hole, and 55-engagement portion.DETAILED DESCRIPTION

[0032] The specific implementations of a contact unit and a rotary isolation switch of the present invention will be further described below in conjunction with the embodiments given in the accompanying drawings. The contact unit and the rotary isolation switch of the present invention are not limited to the description of the following embodiments.

[0033] The rotary isolation switch includes an operating module and a contact module which are laminated. The contact module includes at least one contact unit. The two adjacent contact units are connected in a linkage manner. The at least one contact unit is driven by an operating mechanism of the operating module for opening and closing.

[0034] Specifically, as shown in FIG. 1, each contact unit includes a shell 5. A contact mechanism a, two arc extinguishing systems and a pair of wiring assemblies (not shown) are arranged in the shell 5. The contact mechanism a includes a moving contact assembly 1 and a pair of static contact assemblies 2. Each stationary contact assembly 2 is connected to one wiring assembly. The moving contact assembly 1 rotates between the pair of static contact assemblies 2 for turning on or off a main line in each contact unit. The moving contact assembly 1 includes a rotating shaft 11 and a pair of moving contact portions 120 arranged in the rotating shaft 11. The rotating shaft 11 is rotatably arranged between the pair of static contact assemblies 2. A moving contact bridge 12 is arranged in the rotating shaft 11. Both ends of the moving contact bridge 12 serve as the moving contact portions 120. Each moving contact portion 120 extends along a radial direction of the rotating shaft 11 out of the rotating shaft 11. As the rotating shaft 11 is driven to rotate, each moving contact portion 120 is in contact with or separated from one stationary contact assembly 2. The two adjacent contact units are connected in a linkage manner through the rotating shaft 11, so that the contact mechanisms a in all contact units can be synchronously opened and closed.

[0035] Each arc extinguishing system is fitted on a side of the contact mechanism a, and used to extinguish an electric arc generated when the contact mechanism a is opened. The arc inlet 401 of the arc extinguishing system 401 is joined with the contact mechanism a. Each arc extinguishing system includes an arc extinguishing cover 42 and a grid group 41 arranged in the arc extinguishing cover 42. The electric arc generated when the contact mechanism a is turned off is introduced from the arc inlet 401 of the arc extinguishing cover 42. The electric arc is cut by the grid group 41 to extinguish the electric arc.

[0036] As shown in FIGS. 1-4, an improvement point of the present application lies in that the arc extinguishing system includes an arc extinguishing cover 42, and one end of the arc extinguishing cover 42 serves as the arc inlet 401; the contact mechanism a also includes a housing 3; an accommodating cavity of the housing 3 is provided with two opposing openings; each opening is correspondingly connected to one arc inlet 401; the moving contact assembly 1 and the stationary contact portions 21 are assembled in the accommodating cavity; the moving contact assembly 1 is located between a pair of stationary contact portions 21; and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space. In this way, the contact mechanism a and each of the arc extinguishing systems form a modular structure, which is convenient for assembly and also meets the modular development of the isolation switch. Meanwhile, the housing 3 of the contact mechanism a is docked with the arc inlet 401 of the arc extinguishing cover 42, and the contact mechanism and the arc extinguishing systems on both sides jointly form a relatively closed space, so that the electric arc generated by the contact mechanism a flows within the relatively closed space, thereby improving arc striking and arc extinguishing effects.

[0037] Specifically, as shown in FIG. 5, the housing 3 is provided with a pair of opposing openings. The two pairs of side walls of the housing 3 connected between the pair of openings are a pair of supporting walls 302 and a pair of connecting walls 303, respectively. Each connecting wall 303 is adjacent to one supporting wall 302. The stationary contact portions 21 of each stationary contact assembly 2 are arranged on one connecting wall 303, and the two stationary contact portions 21 are spaced and misaligned to face each other. The moving contact assembly 1 includes a rotating shaft 11 and a moving contact bridge 12 arranged along a radial direction of the rotating shaft 11, wherein the rotating shaft 11 is rotatably supported between the pair of supporting walls 302. That is, the rotating shaft 11 is rotatably supported between the pair of stationary contact portions 21, both ends of the moving contact bridge 12 serve as the moving contact portions 120, and each moving contact portion 120 moves between the pair of connecting walls 303 for cooperation with one stationary contact portion 21.

[0038] Specifically, the arc extinguishing cover 42 is open at both ends. An internal space of the arc extinguishing cover 42 forms an arc extinguishing cavity. One open end of the arc extinguishing cover 42 is used as the arc inlet 401, and the other open end is abutted against and closed by the shell 5. At least one grid group 41 is arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. Each grid group 41 includes a plurality of arc extinguishing grids 411 which are spaced oppositely. An arc extinguishing clearance is formed between every two adjacent arc extinguishing grids 411. A plurality of exhaust holes 423 are formed in a side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401. The exhaust holes 423 are communicated with the arc extinguishing clearance. When the arc inlet 401 is docked with the opening of the housing 3, the arc extinguishing cavity is docked with the accommodating cavity of the housing 3 to form a relatively closed space, thereby improving arc triggering and arc extinguishing effects. Of course, the arc extinguishing cover 42 may also adopt a structure where one end is closed and the other end is open, wherein the open end of the arc extinguishing cover 42 is used as the arc inlet 401, and the closed end may be docked with the shell 5 to achieve limited assembly.

[0039] Further, the moving contact assemblies 1 cooperate with the accommodating cavity to block the two openings from being communicated with each other. For example, the rotating shaft 11 is abutted against an inner side wall of the accommodating cavity, but may affect its rotational smoothness. Preferably, a limiting portion and a barrier portion which cooperate with each other are arranged between the rotating shaft 11 and the accommodating cavity. The limiting portion and the barrier portion block the two openings from being communicated with each other when the rotating shaft 11 rotates to an opening position, which enables the accommodating cavity to be separated into two independent parts while ensuring the rotational smoothness, thereby avoiding the two arc extinguishing systems from interfering with each other through the accommodating cavity.

[0040] Specifically, as shown in FIGS. 7, and 10-12, a circumferential side wall of the rotating shaft 11 is provided with two opening limiting portions 115, opening barrier portions 32 are arranged in the accommodating cavity, and the opening barrier portions 32 are located on a trajectory of the opening limiting portions 115. When the rotating shaft 11 rotates to the opening position, the opening limiting portions 115 are in limiting fit with the opening barrier portions 32, and the rotating shaft 11 and the two opening limiting portions 115 block two openings from being communicated with each other, which can not only play a role of mutual limiting in the opening process, but also increase the air tightness and creepage distance between the arc extinguishing system and the contact mechanism a.

[0041] Further, as shown in FIGS. 25 and 26, each arc extinguishing system includes an arc extinguishing cover 42 and two grid groups 41 which are spaced. The arc extinguishing cover 42 is open at both ends, wherein one open end serves as the arc inlet 401, and the other open end opposite the arc inlet 401 is closed by the shell 5, preferably assembled in the shell 5 and closed by an inner side wall of the shell 5. Of course, the other open end of the arc extinguishing cover 42 is closed by a partition plate arranged in the shell 5, or the arc extinguishing cover 42 may also adopt a structure where one end is closed and the other end is open. Therefore, a relatively closed arc extinguishing cavity is formed inside the arc extinguishing cover 42. The grid groups 41 are arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. An arc extinguishing chamber 40 is formed by the arc extinguishing cover 42 and the grid groups 41 arranged in the arc extinguishing cover 42. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41. The electric arc enters each grid group 41 through the arc inlet 401 and the arc running channel 402. The electric arc is cut by arc extinguishing grids 411 in each grid group 41. A side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401 is provided with a plurality of exhaust holes 423. Exhaust gas generated after the electric arc is cut is discharged from the exhaust holes 423.

[0042] Preferably, as shown in FIGS. 23-26, each arc extinguishing system further includes a short-circuiting plate 44 and / or at least two magnetic conduction plates 43. The short-circuiting plate 44 is arranged at one end of the arc running channel 402 away from the arc inlet 401. The short-circuiting plate 44 enables an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401 to be less than a minimum physical distance between the two grid groups 41. In other words, a distance between one end of each grid group 41 away from the arc inlet and one pin 441 of the short-circuiting plate 44 is less than a minimum physical spacing between the two grid groups 41. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited by means of the short-circuiting plate 44, so that an electric arc current needs to break through the arc extinguishing grids 411 in each grid group 41 before forming a current loop, thereby increasing the utilization rate of the arc extinguishing grids 411 in each grid group 41. Of course, the utilization rate of the arc extinguishing grids 411 can also be increased by using other ways to enable one ends of the two grid groups 41 away from the arc inlet 401 to be equipotentially short-circuited.

[0043] Preferably, the number of magnetic conduction plates 43 is at least two, and the magnetic conduction plates 43 are paired and spaced, so that the arc running channel 402 is located between the at least two magnetic conduction plates 43. After the magnetic conduction plates 43 are magnetized, a magnetic field is correspondingly formed by the magnetic conduction plates 43 in the arc running channel 402. This magnetic field direction is preferably perpendicular to a connecting line between the two grid groups 41, such that the electric arc entering the arc running channel 402 is introduced into the grid groups 41 under the action of the magnetic field, thereby improving the arc quenching ability. The magnetic conduction plates 43 may be embedded in a side wall of the arc extinguishing cover 42, or may be arranged on the surface of an inner side wall of the arc extinguishing cover 42. That is, the magnetic conduction plates 43 are located in the arc extinguishing cavity, but are prone to electric arc stagnation. Preferably, the magnetic conduction plates 43 are arranged on the outer surface of the side wall of the arc extinguishing cover 43, that is, the magnetic conduction plates 43 are located outside the arc extinguishing cavity.

[0044] A specific embodiment of a contact unit is provided in conjunction with FIGS. 1-31.

[0045] As shown in FIGS. 1-4, the contact unit includes a shell 5. A contact mechanism a is arranged in the middle of the shell 5. Arc extinguishing systems are fitted on both sides of the contact mechanism a. The two arc extinguishing systems form a rotationally symmetrical structure with respect to the contact mechanism a. The contact mechanism a includes a housing 3. An accommodating cavity of the housing 3 is provided with two opposing openings. Each arc extinguishing system includes an arc extinguishing cover 42. The arc extinguishing cover 42 is open at one end and closed at the other end, so that a relatively closed arc extinguishing cavity is formed inside the arc extinguishing cover 42. The open end of each arc extinguishing cover 42 is used as the arc inlet 401. Each arc inlet 401 is docked with one opening of the housing 3. That is, the two openings of the housing 3 are seamlessly connected to the open end of the arc extinguishing cover 42 on the same side, such that the arc extinguishing cavity and the accommodating cavity are connected together in an approximately sealed manner to form a relatively closed space. The other open end away from the arc inlet 401 is closely clung to the inner side wall of the shell 5, and is closed by the inner side wall of the shell 5 or by the partition plate arranged in the shell 5, so that one end of the arc extinguishing cavity away from the arc inlet 401 is closed. Of course, when the arc extinguishing cover 42 is a structure where one end is closed and the other end is open, the closed end is closely clung to the inner side wall of the shell 5 to achieve limited installation.

[0046] As shown in FIGS. 5-22, the moving contact assembly 1 includes a rotating shaft 11 and a moving contact bridge 12. The rotating shaft 11 is rotatably supported in the accommodating cavity between the two openings. The moving contact bridge 12 is arranged in the rotating shaft 11 along a radial direction of the rotating shaft 11. Both ends of the moving contact bridge 12, which serve as the moving contact portions 120, extend out of the rotating shaft 11 along the radial direction of the rotating shaft 11. In this embodiment, each moving contact portion 120 corresponds to one opening. That is, when the moving contact assembly 1 rotates to be opened and closed, each moving contact portion 120 moves from one side of one opening to the other side of the same opening. In this process, a partial region of each moving contact portion 120 may extend out of the corresponding opening, that is, move within the open end, which can also be understood that the moving contact portions 120 can partially move within the arc inlet 401.

[0047] Specifically, as shown in FIGS. 5-9, two pairs of side walls of the housing 3 connected between the two openings are a pair of supporting walls 302 and a pair of connecting walls 303, respectively. Each connecting wall 303 is adjacent to one supporting wall 302. A communicating hole 33 is formed in the middle of the pair of supporting walls 302. The rotating shaft 11 is rotatably supported between the pair of connecting walls 303, and each communicating hole 33 is coaxial with the rotating shaft 11. An output shaft of the operating mechanism or a transmission shaft 114 of the adjacent two contact units may pass through the communicating hole 33 and drives the rotating shaft 11 to rotate. A first limiting portion 341 is arranged on the outer surface of each supporting wall 302 in a protruding manner. In this embodiment, as shown in FIGS. 5-9, the first limiting portion 341 is an annular boss surrounding the communicating hole 33, and a second limiting portion 342 is arranged on the outer surface of the connecting walls 303. The second limiting portion 342 in FIGS. 7 and 9 is a strip-shaped groove, and a central axis of the strip-shaped groove is parallel to a central axis of the communicating hole 33. Correspondingly, a first matching portion and a second matching portion are arranged in the shell 5 in which the moving contact assembly 1 is assembled. Specifically, the first matching portion is preferably an annular groove. A central hole is generally formed in the middle of the shell 5. The first matching portion is arranged around the edge of the central hole, and the second matching portion is a convex strip-shaped boss. The first matching portion and the first limiting portion 341 limit the moving contact assembly 1 parallel to an axial direction of the rotating shaft 11, and the second matching portion and the second limiting portion 342 limit the contact mechanism a perpendicular to the axial direction of the rotating shaft 11, which is conducive to ensuring the stability of their assembly.

[0048] In this embodiment, as shown in FIGS. 5-9, the housing 3 includes two plate bodies 301 which are spaced oppositely. The two plate bodies 301 may have the same shape, or different shapes. However, the two plate bodies 301 are encircled to form a hollow cavity body with two open ends. The hollow cavity body as a whole is a "□"-shaped cavity body. A hollow part of the hollow cavity body is used as the accommodating cavity. The two plate bodies 301 may be formed by cooperation of "-" and "" shapes, or may be formed by encircling of two ""-shaped plate bodies 301, or may both be "" shaped.

[0049] As shown in FIGS. 8 and 9, in this embodiment, it is preferred that each plate body 301 has a rectangular plate structure as a whole. Protruding extensions 304 are arranged on both sides of a plate surface of each plate body 301, so that each plate body 301 is in a "" shape. A pair of connecting walls 303 of the housing 3 are formed by cooperation of the extensions 304 on the same side of two plate bodies 301. The two extensions 304 may be lapped or docked to form the connecting walls 303, and the middle parts of the two plate bodies 301 are spaced oppositely to form a pair of supporting walls 302 of the housing 3.

[0050] Further, as shown in FIGS. 7 and 8, splicing structures which cooperate with each other are arranged between the two plate bodies 301. Each splicing structure includes at least a pair of buckle 351 and a clamping groove 352 which cooperate with each other. One plate body 301 is provided with a clamping groove 352 and / or a buckle 351, and the other plate body 301 is provided with a buckle 351 and / or a clamping groove 352. In this embodiment, the clamping groove 352 is formed in the middle of each of the two extensions 304 of one plate body 301, and the buckle 351 is arranged in the middle of each of the two extensions 304 of the other plate body 301 in a protruding manner. When the two extensions 304 are docked to form the connecting walls 303, the buckle 351 and the clamping groove 352 cooperate with each other to form a pluggably detachable structure, which is convenient for the assembly of the rotating shaft 11 in the accommodating cavity.

[0051] As shown in FIGS. 7 and 8, a groove structure serving as the opening barrier portion 32 is arranged at the edge of each extension 304. Each groove structure is an arc-shaped groove and has an opening which is inclined to open toward the housing 3, so that the edge of each extension 304 forms an "S" shape. A central line of each groove structure coincides with a part of movement trajectory of the opening limiting portions 115. In this embodiment, the two opening barrier portions 32 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33.

[0052] Preferably, each connecting wall 303 is provided with an assembling groove 31, each stationary contact assembly 2 cooperates with the moving contact assembly 1 through the assembling groove 31, and the two assembling grooves 31 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33. In this embodiment, the groove structure is formed in the edge of the end surface of each extension 304. When the two extensions 304 are docked, the two groove structures cooperate with each other to form the assembling groove 31. Each assembling groove 31 is located in the middle of the connecting wall 303, and the same connecting wall 303 is provided with one assembling groove 31 and one opening barrier portion 32. That is, one stationary contact portion 21 and one opening barrier portion 32 are located on the connecting walls 303 on both sides of the same opening of the housing 3, and the stationary contact assembly 2 can be clamped when the two extensions 304 are docked, thereby achieving stable fit of the stationary contact assembly 2 and the housing 3.

[0053] Of course, the housing 3 may also not be provided with an assembling groove 31, and the stationary contact assembly 2 extends from the opening of the housing 3 into the housing 3 to cooperate with the moving contact assembly 1, but may affect the fit airtightness of the housing 3 and the arc extinguishing cover 42.

[0054] Further, at least one group of positioning structures may also be arranged between the two plate bodies 301. Each positioning structure includes a positioning boss (not shown) and a positioning groove 361. One of the plate bodies 301 is provided with a positioning boss and / or a positioning groove 361, while the other plate body 301 is provided with a positioning groove 361 and / or a positioning boss. In this embodiment, the two extensions 304 of one of the plate bodies 301 are respectively provided with one positioning groove 361, and the two positioning grooves 361 form a rotationally symmetrical structure with respect to the central axis of the communicating hole 33. That is, the two positioning grooves 361 in FIG. 8 are located at the corners of the same plate body 301, respectively. The two extensions of the two plate bodies 301 are respectively provided with one positioning boss, and each positioning boss is positioned in cooperation with one positioning groove 361, thereby facilitating assembly.

[0055] In addition, the two extensions 304 may be fixed together, for example, by screws, or adhered by hot riveting, ultrasonic riveting and other processes. At this time, the two extensions 304 may be docked through end surfaces or come into contact through side surfaces, which can ensure the stability of the housing 3, but is not convenient for disassembly and assembly. In this case, it is necessary to provide assembling grooves 31 in the connecting walls 303.

[0056] Of course, the housing 3 may also be of an integrated structure (see FIG. 5), in which case the connecting walls 303 are of an integrated structure, the assembling groove 31 is directly formed in the middle of the connecting wall 303, and the opening barrier portion 32 is arranged at the same position in the accommodating cavity.

[0057] In this embodiment, an axial height of the rotating shaft 11 is greater than or equal to a spacing between a pair of supporting walls 302. A circumferential side wall of the rotating shaft 11 is provided with two opening limiting portions 115 in a protruding manner. The rotating shaft 11 and the two opening limiting portions 115 block the two openings of the accommodating cavity from being communicated with each other. Preferably, both ends of the rotating shaft 11 are rotatably abutted against the supporting walls 302. That is, rotating surfaces of the rotating shafts 11 are rotatably abutted against the supporting walls 302 to limit the axial movement of the rotating shaft 11, thereby closing a clearance between the rotating shaft 11 and the communicating hole 33. When the rotating shaft rotates to the opening position, the two opening limiting portions 115 are abutted against the accommodating cavity (an inner side wall of the housing 3) to block the two openings from being communicated with each other. Further, the opening barrier portions 32 are arranged in the accommodating cavity. The opening barrier portions 32 are located on a movement trajectory of the opening limiting portions 115. When the rotating shaft 11 rotates to the opening position, the opening limiting portions 115 and the opening barrier portions 32 cooperate with each other to limit the rotating shaft 11 from further rotation. The thickness of the opening limiting portion 115 and / or the opening barrier portion 32, or, the overall thickness of the opening limiting portion 115 and the opening barrier portion 32 after cooperation is equal to a distance between the pair of supporting walls 302. Therefore, the two openings of the accommodating cavity are blocked from being communicated with each other, thereby achieving the effects of airtight guidance and increasing the creepage distance.

[0058] Of course, when the opening limiting portions 115 are not used to block the communication of the two openings of the housing 3, the opening limiting portions 115 may also be arranged in other positions of the rotating shaft 11. For example, the opening limiting portions 115 are arranged on the rotating surface of the rotating shaft 11. In this case, each opening barrier portion 32 is an arc-shaped trajectory groove formed in the supporting wall 302, and the opening of the arc-shaped trajectory groove faces the opening limiting portion 115. After the rotating shaft 11 rotates to the opening position, the opening limiting portion 115 is abutted against a closed end of the arc-shaped trajectory groove.

[0059] As shown in FIGS. 6, 7, and 10-16, the rotating shaft 11 is cylindrical as a whole. The two moving contact portions 120 extend along the radial direction of the rotating shaft 11 out of the rotating shaft 11, and the circumferential side wall of the rotating shaft 11 is provided with the opening limiting portions 115 in a protruding manner. Two opening limiting portions 115 are shown in FIGS. 1, 11 and 12, respectively. The two opening limiting portions 115 form a rotationally symmetrical structure with respect to an axis of the rotating shaft 11, and each opening limiting portion 115 is adjacent to one moving contact portion 120, so as to avoid a large clearance between the opening limiting portion 115 and the moving contact portion 120 to limit a rotation angle of the rotating shaft 11. As the rotating shaft 11 rotates in the housing 3, each moving contact portion 120 and the opening limiting portion 32 adjacent to the moving contact portion 120 move together between the stationary contact portion 21 and the opening barrier portion 32 on both sides of the same opening. During opening, the opening limiting portion 115 is located on a side of the moving contact portion 120 away from the stationary contact portion 21.

[0060] A specific structure of a split rotating shaft 11 is provided in conjunction with FIGS. 7, and 10-12. The rotating shaft 11 includes a contact support 111, and a cover plate 112 covering the contact support 111.

[0061] As shown in FIGS. 10-14, the contact support 111 is cylindrical as a whole. A radial groove 1111 is formed in the surface on one side of the contact support 111. The radial groove 111 is open at both ends. The moving contact bridge 12 is assembled in the radial groove 1111, and both ends of the moving contact bridge 12 extend out of the contact support 111 to form two moving contact portions 120. Two transmission shafts 114 are formed on both sides of the radial groove 111 in a protruding manner. The transmission shafts 114 can also provide a certain limiting effect on the moving contact bridge 12. Two bosses serving as the opening limiting portions 115 are arranged on a circumferential side wall of the contact support 111 in a protruding manner. The two bosses form a rotationally symmetrical structure with respect to the axis of the contact support 111, and each boss is located immediately adjacent to the open side of the radial groove 1111. A rotating portion 113 is arranged on the surface of the other side of the contact support 111 in a protruding manner. The rotating portion 113 is located in the center position of the contact support 111. The rotating portion 113 is in running fit with the communicating hole 33 of one supporting wall 302. A transmission groove 117 is formed in each of both sides of the rotating portion 113, and each transmission groove 117 is coaxial with the corresponding transmission shaft 114. It should be noted that the transmission shafts 114 may also be assembled separately on the contact support 111. The transmission shafts 114 may also not be provided in pairs, but the transmission shafts 114 are preferably located at a position deviating from the axis of the contact support 111, and a plurality of transmission shafts 114 preferably form a rotationally symmetrical structure with respect to the axis of the contact support 111.

[0062] As shown in FIGS. 10-12, 15, and 16, the cover plate 112 is disc-shaped as a whole. Two through holes 1121 are formed in the middle of the cover plate 112. Each through hole 1121 is coaxial with the transmission shaft 114 of the contact support 111. When the cover plate 112 covers the contact support 111, each transmission shaft 114 correspondingly passes through one through hole 1121 and then penetrates out of the housing 3 from the communicating hole 33 of one supporting wall 302, for plugging with the transmission groove 117 of the adjacent moving contact assembly 1. The transmission shafts 114 are located at a position deviating from the axis of the rotating shaft 11, which is conducive to providing a stable linkage connection. Two bosses serving as the opening limiting portions 115 are arranged on the edge of the cover plate 112 in a protruding manner, and each boss located on the cover plate 112 is in one-to-one correspondence to the boss located on the contact support 111. Of course, it is also possible to arrange the bosses serving as the opening limiting portions 115 only on the cover plate 112 or the contact support 111.

[0063] As shown in FIGS. 7, and 1-12, the contact support 111 and the cover plate 112 in this embodiment are connected together through at least one fastener 13. That is, engagement grooves 116 are formed in an edge of one side of the contact support 111 away from the cover plate 112 and an edge of one side of the cover plate 112 away from the contact support 111, respectively. When the cover plate 112 covers the contact support 111, the cover plate 112 corresponds to the engagement groove 116 on the same side of the contact support 111 and is then clamped into the fastener 13. Therefore, the contact support 111 and the cover plate 112 are connected together. In this embodiment, the cover plate 112 and the contact support 111 are connected together through two fasteners 13, the two fasteners 13 are symmetrically arranged on both opposite sides of the rotating shaft 11, and a central connecting line of the two fasteners 13 is perpendicular to a central axis of the moving contact bridge 12. That is, the fasteners 13, the engagement grooves 116 and the transmission shafts 114 are located on the same diameter of the rotating shaft 11, and this diameter is perpendicular to the axis of the moving contact bridge 12.

[0064] In addition, the fasteners 13 and the cover plate 112 or the contact support 111 may be of an integrated structure. For example, the fastener 13 and the cover plate 112 may be of an integrated structure, in which case the engagement groove 116 is only formed in the edge of the contact support 111; or the fastener 13 and the contact support 111 are of an integrated structure, in which case the engagement groove 116 is only formed in the edge of the cover plate 112. It should be noted that the cover plate 112 and the contact support 111 may also be connected by means of other connection ways that facilitate disassembly. In addition, the contact support 111 and the cover plate 112 may also be riveted and fixed by rivets, or welded by hot melting, ultrasonic welding and other processes.

[0065] A specific structure (not shown) of an integrated rotating shaft 11 is provided. The rotating shaft 11 includes a cylindrical rotating body. A radial groove 1111 in which a moving contact bridge 12 is assembled is provided inside the rotating body. Both ends of the radial groove 1111 penetrate through a circumferential side wall of the rotating body, so that two moving contact portions 120 of a moving contact may extend from an open part of the radial groove 1111 out of the rotating body. Opening barrier portions 32 are arranged on a circumferential side wall of the rotating body in a protruding manner. Each opening barrier portion 32 is adjacent to one moving contact portion 120. A rotating portion 113 is arranged at a center position of one side of the rotating body in a protruding manner. The rotating portion 113 is in running fit with the communicating hole 33 of the housing 3. The rotating portion 113 is provided with at least one transmission groove 117, and the transmission groove 117 is located in a position deviating from the axis, for plugging with the transmission shaft 114 of the adjacent moving contact assembly 1. At least one transmission shaft 114 is arranged on the other side of the rotating body in a protruding manner. The transmission shaft 114 is located at a position deviating from the axis of the rotating body. The number of the transmission shafts 114 is preferably two, and the two transmission shafts 114 form a rotationally symmetrical structure with respect to the axis of the rotating shaft 11.

[0066] The moving contact bridge 12 assembled in the rotating shaft 11 may adopt the prior art. That is, the moving contact bridge 12 includes two moving contact pieces 121 which are opposite in parallel. Moving contact portions 120 are correspondingly formed at the same ends of the two moving contact pieces 121, with a clamping clearance 1201 between the two moving contact portions. Each moving contact piece 121 has a certain elasticity and can provide a clamping force for the clamping clearance 1201. Each moving contact portion 120 extends along the radial direction of the rotating shaft 11 out of the rotating shaft 11. As the rotating shaft 11 is driven to rotate, each moving contact portion 120 comes into contact with or is separated from the stationary contact portion 21 of one stationary contact assembly 2.

[0067] Preferably, as shown in FIGS. 12, and 17-20, the moving contact bridge 12 in this embodiment further includes at least two elastic members 122. At least one elastic member 122 is arranged on one side of one moving contact portion 120. The elastic member 122 provides a clamping force for the clamping clearance 1201. By changing the applied torque, the pressure for the clamping clearance 1201 can be adjusted, so that the clamping clearance 1201 has a stable clamping force, so as to ensure the fit stability between the moving contact portions 120 and the stationary contact portions 21.

[0068] Preferably, the elastic member 122 is sleeved outside each of the two moving contact pieces 121, so that the elastic members 122 and the moving contact pieces 121 form a stable clamping relationship, which is convenient for disassembly and assembly and also can ensure that the clamping clearance 1201 is provided with a stable clamping force. Further, as shown in FIG. 21, the elastic member 122 sleeved outside each of the two moving contact pieces 121 is provided with an elastic opening 1222. In this case, the elastic member 122 has a U-shaped structure as a whole, and a clearance between the elastic openings 1222 is less than or equal to the clamping clearance 1201. When the stationary contact portion 21 is plugged into the clamping clearance 1201, the elastic opening 1222 is enlarged and the elastic member 122 undergoes elastic deformation. The elastic member 122 provides a reverse pressure to the moving contact piece 121 to ensure the contact pressure between the moving contact portion 120 and the stationary contact portion 21, that is, to ensure the contact resistance and also reliable contact. Of course, the elastic member 122 may also be of a closed annular structure, such as an "o" structure formed by a rubber part, or a "□" shape formed by bending a spring steel wire or a reed.

[0069] Further, the moving contact piece 121 is also provided with a limiting groove 1211 for limiting the elastic member 122, and a central axis of the limiting groove 1211 is perpendicular to a central axis of the moving contact piece 121 to prevent the elastic member 122 from shifting during the deformation process. Preferably, the limiting grooves 1211 are formed in both sides of the moving contact piece 121 to avoid too many structures on the moving contact piece 121, which is not conducive to ensuring the stability. Preferably, a plurality of the limiting grooves 1211 are provided, and at least one spare limiting groove is reserved among the plurality of the limiting grooves 1211, such that the elastic member 122 has a plurality of assembling positions that can be adjusted. By changing a position of the elastic member 122 where a force value is applied to change a force arm for deformation of the moving contact bridge, the clamping force exerted by the elastic member on the moving contact bridge is adjusted, which is conducive to adjusting the additional clamping force provided by the elastic member 122 for the clamping clearance.

[0070] An embodiment of a moving contact bridge 12 is provided in conjunction with FIGS. 11, 12, and 17-21.

[0071] As shown in FIGS. 12 and 17, the moving contact bridge 12 includes two moving contact pieces 121, two elastic members 122, and a supporting member 123. The two moving contact pieces 121 are parallel and spaced oppositely. The center positions of the two moving contact pieces 121 are connected together through the supporting member 123. Moving contact portions 120 are cooperatively formed at the same ends of the two moving contact pieces 121, with a clamping clearance 1201 between the moving contact portions. The elastic member 122 is arranged between each moving contact portion 120 and the supporting member 123. The elastic member 122 provides additional clamping force to the clamping clearance 1201. In this embodiment, the elastic member 122 is preferably of a U-shaped structure. Of course, the elastic member 122 may also be of an annular structure sleeved outside the two moving contact pieces 121. In addition, more than one elastic member 122 may also be arranged between each moving contact portion 120 and the supporting member 123 according to actual needs.

[0072] As shown in FIGS. 17-21, the moving contact piece 121 in this embodiment includes a contact piece body. The contact piece body is a strip-shaped platy conductor. A positioning hole 1212 is formed in the middle of the contact piece body. Both end edges of the contact piece body extend outward to form a guide piece 1210. Two guide pieces 1210 of each contact piece body form a rotationally symmetrical structure with respect to the positioning hole 1212. In FIGS. 17-19, the two guide pieces 1210 of the same contact piece body extend in opposite directions respectively, and the same ends of the two moving contacts 121 are spaced oppositely to form the moving contact portion 120. At this time, a part of a clearance between the two moving contact pieces 121, which corresponds to the moving contact portion 120, is the clamping clearance 1201. Two guide pieces 1210 which are spaced oppositely are arranged on the same side of the same moving contact portion 120. The guide pieces 1210 provide a guiding role for the stationary contact assembly 2. The stationary contact portion 21 of the stationary contact assembly 2 enters the clamping clearance 1201 from the guide pieces 1210. A clamping groove 1211 is formed in the contact piece body between each guide piece 1210 and the positioning hole 1212. Preferably, the number of limiting grooves 1211 is greater than or equal to the number of elastic members 122, and the excess limiting grooves 1211 are used as spare limiting grooves to facilitate the adjustment of the assembly positions of the elastic members 122, thereby adjusting the clamping force of the elastic members 122. Of course, when the number of limiting grooves 1211 is equal to the number of elastic members 122, their assembly positions cannot be adjusted. In FIGS. 19 and 20, a pair of limiting grooves 1211 are formed in both side edges of the contact piece body between each guide piece 1210 and the positioning hole 1212, two pairs of limiting grooves 1211 of the same contact piece body form a rotationally symmetrical structure with respect to the positioning hole 1212, and the central axis of each limiting groove 1211 is perpendicular to the central axis of the contact piece body.

[0073] As shown in FIGS. 17 and 21, the elastic member 122 in this embodiment is of a U-shaped structure equipped with an elastic opening 1222. Specifically, the elastic member 122 includes two elastic arms 1221 which are spaced oppositely. One ends of the two elastic arms 1221 are bent in opposite directions and connected together to form an integrated structure and clamped into the limiting grooves 1211 on one side edge of the contact piece body, while the other ends of the two elastic arms 1221 are bent in opposite directions and are spaced oppositely to form the elastic opening 1222. A clearance between the elastic openings 1222 is less than or equal to a spacing between the two moving contact pieces 121, and the tail ends of the two elastic arms 1221 which form the elastic opening 1222 are correspondingly clamped into the limiting groove 1211 in the other side edge of the contact piece body, respectively. In this embodiment, the elastic arms 1221 of the elastic member 122 are perpendicular to the central axis of the contact piece body, and the elastic opening 1222 and the guide piece 1210 are located on the same side of the moving contact bridge 12. When the stationary contact portion 21 enters into the clamping clearance 1201, the stationary contact portion 21 may correspondingly enlarge the elastic opening 1222, so that the elastic member 122 undergoes elastic deformation. The degree of freedom of the two moving contact pieces 121 can be adaptively adjusted, and the risk of poor collision-induced closing caused by non-centering of the moving contact portion 120 and the stationary contact portion 21 due to manufacturing errors of the parts is reduced.

[0074] As shown in FIG. 17, the supporting member 123 includes a body 13. In FIG. 17, the body 13 is cylindrical. Camshaft 1232 are arranged at both opposite ends of the body 13 in a protruding manner. Each camshaft 1232 is correspondingly plugged into the positioning hole 1212 of one moving contact piece 121. A spacing between the two moving contact pieces 121, i.e., the clamping clearance 1201 of each moving contact portion 120, is limited by an axial height of the body 13.

[0075] The stationary contact assembly 2 which cooperates with the moving contact assembly 1 may adopt the prior art. In this embodiment, preferably, as shown in FIGS. 5-7, the stationary contact assembly 2 includes electric conduction plates, and each electric conduction plate correspondingly passes through one assembling groove 31. When the housing 3 is spliced by two plate bodies 301, each electric conduction plate is preferably clamped under the action of two plate bodies 301. A stationary contact portion 21 is arranged at one end of the electric conduction plate, and the stationary contact portion 21 extends into the accommodating cavity and used to cooperate with the moving contact portion 120. The two stationary contact portions 21 are spaced within the accommodating cavity and form a rotationally symmetrical structure with respect to the axis of the rotating shaft 11 (communicating hole 33). A wiring portion 22 is arranged at the other end of the electric conduction plate. Each wiring portion 22 is located outside the housing 3 for connection with a wiring assembly. When the moving contact assembly 1 in this embodiment cooperates with the stationary contact assembly 2, the elastic opening 1222 of the elastic member 122 preferably faces the stationary contact portion 21.

[0076] It should be noted that when the moving contact assembly 1 and the stationary contact assembly 2 are arranged in the housing 3, the transmission shaft 114 and the rotating portion 113 of the rotating shaft rotate to pass through one communicating hole 33 of the housing 3, respectively; and the two moving contact pieces 121 of the moving contact bridge 12 are spaced oppositely between a pair of supporting walls 302 of the housing 3.

[0077] As shown in FIGS. 1 and 23-26, each arc extinguishing system is cooperatively arranged on a side of the contact mechanism a, and used to extinguish an electric arc generated when the contact mechanism a is opened. The arc inlet 401 of the arc extinguishing system corresponds to the contact mechanism a. Each arc extinguishing system includes an arc extinguishing cover 42 and two grid groups 41 which are spaced. The arc inlet 401 which is joined with the contact mechanism a is formed in one end of the arc extinguishing cover 42. Each grid group 41 is arranged in the arc extinguishing cover 42 on one side of the arc inlet 401. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41.

[0078] In this embodiment, one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited. In this way, when the electric arc current is expected to form a loop, it must break through all the arc extinguishing grids 411 in each grid group 41. The current is jointly limited by the two grid groups 41, so that the arc extinguishing grids 411 can be fully utilized, thereby improving the arc extinguishing ability of the arc extinguishing systems.

[0079] Further, the arc extinguishing system also includes a short-circuiting plate 44 (see FIGS. 25 and 26) or a connecting grid group 41. The short-circuiting plate 44 or the connecting grid group 41 is arranged in the arc running channel 402, so that one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the short-circuiting plate 44 or the connecting grid group 41. The short-circuiting plate 44 is small in size, and suitable for contact units with small internal spaces. The connecting grid group 41 occupies more space, but at the same time has an effect of cutting the electric arc and achieves a better arc extinguishing effect. In addition, it is also applicable for equipotential short-circuiting by directly connecting tail grids in the two grid groups away from one end of the arc inlet 401, without providing the short-circuiting plate 44 or the connecting grid group.

[0080] Further, as shown in FIGS. 23 and 24, each arc extinguishing system further includes at least two magnetic conduction plates 43. The arc running channel 402 is located between the at least two magnetic conduction plates 43. A magnetic field is formed by the magnetic conduction plates 43 in the arc running channel 402. In this way, two grid groups 41 are arranged in the relatively closed arc extinguishing cover 42. The arc running channel 402 between the two grid groups 41 is correspondingly located between the magnetic conductive plates 43. The magnetic conduction plates 43 form a magnetic field within the arc running channel 402, which facilitates blowing the electric arc toward the grid groups 41. The relatively closed arc extinguishing cover 42 can extend the cooperation time of the electric arc and the grid groups 41, thereby improving an arc extinguishing effect.

[0081] Further, each magnetic conduction plate 43 is attached to the side wall of the arc extinguishing cover 42 along one side of the arc running channel 402, and the width of each magnetic conduction plate 43 is approximately equal to a spacing between the two grid groups 41. Preferably, the width of each magnetic conduction plate 43 is equal to the spacing between the two grid groups 41. The magnetic conduction plates 43 may be embedded into the side wall of the arc extinguishing cover 42, or may be attached to the inner or outer surface of the side wall of the arc extinguishing cover 42. The magnetic conduction plates 43 with smaller sizes are conducive to reducing the cost. Of course, in a case where the size of each magnetic conduction plate 43 is relatively large, the magnetic conduction plate 43 is preferably arranged on the outer surface of the side wall of the arc extinguishing cover 42.

[0082] In addition, the two grid groups 41 may be assembled together in one arc extinguishing cover 42 to form an arc extinguishing chamber 40, or the two grid groups 41 are correspondingly assembled in the two arc extinguishing covers 42 respectively to form two independent arc extinguishing chambers 40, which can meet different product needs.

[0083] A first embodiment of an arc extinguishing system is provided in conjunction with FIGS. 1, and 23-31.

[0084] As shown in FIGS. 23-31, the arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41, a short-circuiting plate 44, and a pair of magnetic conduction plates 43. An arc inlet 401 is formed in one end of the arc extinguishing cover 42 and used to introduce the electric arc into the arc extinguishing system in cooperation with the contact mechanism a. The two grid groups 41 are spaced oppositely and arranged on one side of the arc inlet 401. A spacing between the two grid groups 41, which is used as the arc running channel 402, is communicated with the arc inlet 401. The short-circuiting plate 44 is arranged at an end of the arc running channel 402 away from the arc inlet 401. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially connected through the short-circuiting plate 44. A pair of magnetic conduction plates 43 are spaced, and the arc running channel 402 is located between the pair of magnetic conduction plates 43. After the pair of magnetic conduction plates 43 are magnetized, a magnetic field is correspondingly generated within the arc running channel 402. Specifically, each magnetic conduction plate 43 is arranged on a side wall of the arc extinguishing cover 42 corresponding to the arc running channel 402, and the magnetic conduction plate 43 may be optionally embedded into the side wall of the arc extinguishing cover 42. Preferably, the magnetic conduction plates 43 are attached to an outer side wall of the arc extinguishing cover 42 for easy disassembly and assembly.

[0085] As shown in FIGS. 25-28, the arc extinguishing cover 42 includes two cover bodies 421 which are spaced oppositely. The two cover bodies 421 are encircled to form a hollow cavity with two open ends. In drawings, the arc extinguishing cover 42 is in a "□"-shape as a whole. In this case, an arc extinguishing cavity with two open ends is formed inside the arc extinguishing cover 42. One open end of the arc extinguishing cavity is used as the arc inlet 401, and the other open end opposite the arc inlet 401 is closed by the shell 5, preferably assembled in the shell 5 and closed by the inner side wall of the housing 5. Of course, the other open end of the arc extinguishing cover 42 is closed by a partition plate arranged in the shell 5. Therefore, the arc extinguishing cavity forms a relatively closed cavity body, and the side wall of the arc extinguishing cover 42 adjacent to the arc inlet 401 is provided with a plurality of exhaust holes 423, and the plurality of exhaust holes 423 are spaced along a direction away from the arc inlet 401.

[0086] As shown in FIGS. 25, 26 and 29, two grid groups 41 are arranged in the arc extinguishing cover 42. Each grid group 41 includes a plurality of arc extinguishing grids 411 which are spaced. An arc extinguishing clearance is formed between every two adjacent arc extinguishing grids 411. At least part of the arc extinguishing clearance is correspondingly communicated with the exhaust holes 423. An arc extinguishing notch 412 is formed in one end of each arc extinguishing grid 411. The arc extinguishing notches 412 of the same grid group 41 are communicated to form an arc extinguishing groove 410. The arc extinguishing groove 410 faces the arc running channel 402. One end of the arc extinguishing groove 410 is communicated with the arc inlet 401. The arc extinguishing grooves 410 of the two grid groups 41 are spaced oppositely. In this embodiment, each arc extinguishing notch 412 extends away from the opening direction along a direction deviating from the axis, such that the entire arc extinguishing notch 412 is in a "y" shape. The extensions 304 of the two adjacent arc extinguishing notches 412 are misaligned against each other, which is conducive to improving the cutting of the electric arc by the arc extinguishing grids 411. Of course, each grid group 41 may adopt the prior art.

[0087] Two mounting areas are provided in the arc extinguishing cavity. The two mounting areas are spaced oppositely, and each mounting area is correspondingly equipped with a grid group 41. Preferably, each mounting area includes a plurality of grid slots 424 which are spaced. The grid slots 424 and the exhaust holes 423 are located in adjacent side walls of the arc extinguishing cover 422, respectively. An arc extinguishing grid 411 is correspondingly plugged into each grid slot 424.

[0088] In this embodiment, as shown in FIGS. 23-28, docking portions 422 are arranged on both side edges of each cover body 421. The cover body 421 provided with the docking portion 422 is in a "" shape as a whole. A plurality of grid slots 424 which are spaced are formed in the middle of the same cover body 421. The docking portions 422 on the same side of the two cover bodies 421 cooperate with each other to form side walls of the arc extinguishing cover 32 where the exhaust holes 423 are formed. In FIGS. 23-28, a plurality of opening grooves, which are used as the exhaust holes 423, are spaced on the edge of each docking portion 422, and the plurality of exhaust holes 423 are arranged equidistantly. When the docking portions 422 of the two cover bodies 421 are docked, the exhaust holes 423 of the two docking portions 422 located on the same side are misaligned against each other, so that electric arcs and electric arc particles can be prevented from being short-circuited outside the arc extinguishing cover 42. Of course, the exhaust holes 423 formed in each docking portion 422 may also be through holes 1121.

[0089] Of course, the docking portions 422 are formed in both side edges of one cover body 421 which is in a "" shape as a whole, while the other cover body 421 which is not provided with the docking portion 422 is in a "-" shape as a whole. Alternatively, the cover bodies may be encircled to form the arc extinguishing cover 42 which is open at both ends. In this case, the exhaust holes 423 are formed in the middle of each docking portion 422, and every two adjacent exhaust holes 423 are misaligned against each other. Alternatively, the docking portion 422 is formed on a single side of each cover body 421, such that each cover body 421 is in a "" shape as a whole. The docking portion 422 of each cover body 421 is provided with a plurality of exhaust holes 423.

[0090] As shown in FIGS. 25, 26 and 30, the short-circuiting plate 44 is located at an end of the arc running channel 402 away from the arc inlet 401. Two pins 441 of the short-circuiting plate 44 are respectively adjacent to one ends of the two grid groups 41 away from the arc inlet 401, so that an electric clearance between the two grid groups 41 away from the arc inlet 401 is less than a minimum physical spacing between the two grid groups 41. That is, a distance between one end of each gate group 41 way from the arc inlet 401 and one pin 441 is less than the minimum physical spacing between the two gate groups 41, so that an electric arc current forms a loop and needs to flow through the short-circuiting plate 44, thereby achieving equipotential short-circuiting of one ends of the two gate groups 41 away from the arc inlet 401. Further, the short-circuiting plate 44 also includes an arc striking plate 442. The arc striking plate 422 is connected to the two pins 441 and extends along a center line of the arc running channel 402 in a direction close to the arc inlet 401. The arc striking plate 442 is used to bridge an electric arc.

[0091] As shown in FIGS. 25, 26 and 30, the short-circuiting plate 44 includes two arc striking pieces. One ends of the two arc striking pieces are attached to form the arc striking plate 422. A notch is formed in an end portion of the arc striking plate 442. This notch is located between two grid groups 41 to play a communicating role. The middle parts of the two arc striking pieces are deflected toward both sides respectively to form deflected segments. The end portion of each deflected segment is bent to form one pin 441, so that the short-connecting plate 44 is in a "herringbone" shape as a whole. Each pin 441 is spaced opposite to the corresponding arc extinguishing grid 411 in one grid group 41 away from the arc inlet 401, and a clearance between the pin 441 and the arc extinguishing grid 411 is much less than the spacing between the two grid groups 41. In drawings, each pin 441 is spaced opposite to the arc extinguishing notch 412 of the arc extinguishing grid 411 in the grid group 41 away from the arc inlet 401.

[0092] Further, as shown in FIGS. 25, 26 and 28, short-circuiting plate mounting portions are arranged in the arc extinguishing cover 42. The short-circuiting plate 44 is assembled in the arc running channel 402 by the short-circuiting plate mounting portion in a limiting manner. The short-circuiting plate mounting portions are formed in the middle of at least one cover body 421. The short-circuiting plate mounting portions and the exhaust holes 423 are arranged on two adjacent side walls of the arc extinguishing cover 42, respectively. Preferably, the short-circuiting plate mounting portion is arranged in the middle of each of the two cover bodies 421. When the two cover bodies 421 are encircled to form the arc extinguishing cover 42, the short-circuiting plate mounting portions are used to limit the short-circuiting plate 44. As shown in FIG. 28, the short-circuiting plate mounting portion includes a first boss 4261 and a second boss 4262 which are spaced. The first boss 4261 is located at an end of the arc running channel 402 close to the arc inlet 401, while the second boss 4262 is located at an end of the arc running channel 402 away from the arc inlet 401. The short-circuiting plate 44 is assembled between the first boss 4261 and the second boss 4262 in a limiting manner. In drawings, a notch is formed in a side of the first boss 4261 facing the second boss 4262. This notch is engaged with the arc striking plate 442 of the short-circuiting plate 44. The second boss 4262 is in a triangular shape as a whole, which is used to separate and limit the two pins 441 of the short-circuiting plate 44, so that the two pins 441 of the short-circuiting plate 44 extend toward the two grid groups 41, respectively. Of course, the short-circuiting plate 44 may also be fitted to the arc extinguishing cover 42 in other ways.

[0093] In addition, a pair of magnetic conduction plates 43 are spaced oppositely, and the arc running channel 402 is located between the pair of magnetic conduction plates 43, such that a magnetic field is formed in the arc running channel 402 after the pair of magnetic conduction plates 43 are magnetized. The magnetic field direction is perpendicular to a connecting line direction between the two grid groups 41 to accelerate the introduction of the electric arc into the two grid groups 41.

[0094] As shown in FIGS. 23, 24 and 27, a magnetic conduction plate mounting portion is arranged in the middle of each cover body 421. Preferably, the magnetic conduction plate mounting portion is located outside the arc extinguishing cavity. In this embodiment, the magnetic conduction plate mounting portion is located on the outer surface of the cover body 421, that is, arranged on each of the outer surfaces of the two cover bodies 421. Specifically, the magnetic conduction plate mounting portion includes a magnetic conduction plate mounting groove 4251 and a fastening boss 4252 arranged in the magnetic conduction plate mounting groove 4251. In FIG. 27, the magnetic conduction plate mounting groove 4251 is formed in the outer surface of the cover body 421, and each magnetic conduction plate mounting groove 4251 corresponds to the arc running channel 402. At least one fastening boss 4252 is arranged at the bottom of the magnetic conduction plate mounting groove 4251 in a protruding manner, and the fastening boss 4252 is correspondingly plugged into the fastening groove 431 of the magnetic conduction plate 43. In FIGS. 23, 24 and 31, the magnetic conduction plate 43 is of a rectangular platy structure, and two fastening grooves 431 are formed in the middle of the magnetic conduction plate 43. Of course, it is also possible to not provide the fastening boss 4252, and the magnetic conduction plate 43 is directly embedded or adhered into the magnetic conduction plate mounting groove 4251.

[0095] In addition, the arc extinguishing cover 42 may also be provided with a limited assembly structure, so that the arc extinguishing cover 42 is stably assembled in the shell 5 of the contact unit. In FIGS. 23, 24, 27 and 28, an engagement groove 427 is formed in an edge of the arc extinguishing cover 42 away from the arc inlet 401. When the arc extinguishing cover 42 is assembled in the shell 5 of the isolation switch, the engagement groove 427 may be engaged with an engagement portion (not shown) in the shell 5 to achieve stable assembly. Of course, it is also possible to assemble directly through fasteners such as screws without providing a limited assembly structure.

[0096] A second embodiment (not shown) of an arc extinguishing system is provided.

[0097] The arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41 and a pair of magnetic conduction plates 43. The structures of the arc extinguishing cover 42, the grid groups 41 and the magnetic conduction plates 43 are the same as those of the first embodiment, but different from the first embodiment in that: the arc extinguishing system in this embodiment is no longer provided with a short-circuiting plate 44, but a connecting grid group is arranged between the two grid groups 41; the connecting grid group is arranged at an end of the arc running channel 402 away from the arc inlet 401; and both ends of the connecting grid group are spaced opposite to one end of each grid group 41 away from the arc inlet 401, so that an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401 is less than a minimum physical spacing between the two grid groups 41, that is, a distance between one end of each grid group 41 away from the arc inlet 401 and one end of the connecting grid group, i.e., an electric clearance between one ends of the two grid groups 41 away from the arc inlet 401, is less than the minimum physical spacing between the two grid groups 41.

[0098] Specifically, the connecting grid group includes a plurality of connecting grids which are spaced. The connecting grids close to the grid group 41 are spaced opposite to the arc extinguishing grids 411 in the grid group 41 away from one end of the arc inlet 401. Therefore, one ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this embodiment, the structure of the connecting grids is preferably the same as the arc extinguishing grids 411 in the grid group 41. Correspondingly, an arc extinguishing notch 412 is also formed in one end of each connecting grid. The arc extinguishing notches 412 of the connecting grid group 41 are communicated, and are communicated with the arc extinguishing grooves 410 of the two grid groups 41, respectively.

[0099] In this embodiment, the connecting grid group is arranged along a straight line connected between the two grid groups 41. Therefore, the two grid groups 41 and the connecting grid group form a "U"-shaped structure in the arc extinguishing cover 42. Of course, the connecting grid group may also be arranged along an arc line connected between the two grid groups 41. Preferably, a concave surface of the arc line faces the arc inlet 401. Therefore, the two grid groups 41 and the connecting grid group 41 also form a "U"-shaped structure in the arc extinguishing cover 42. Alternatively, the connecting grid group 41 may also be arranged along a fold line connected between the two grid groups 41, for example, along an inverted "V"-shaped fold line. Preferably, a spacing between the two grid groups 41 away from the arc inlet 401 gradually decreases. Therefore, the two grid groups 41 and the connecting grid group 41 form a "W"-shaped structure in the arc extinguishing cover 42.

[0100] A third embodiment (not shown) of an arc extinguishing system is provided.

[0101] In this embodiment, the arc extinguishing system includes an arc extinguishing cover 42 which is the same as that in the first embodiment. Two grid groups which are the same as those in the first embodiment are arranged in the arc extinguishing cover 42. An arc running channel 402 which is communicated with the arc inlet 401 is formed between the two grid groups 41. The arrangement mode of the arc extinguishing grids 411 in each grid group 41 may refer to the first embodiment. The third embodiment is different from the first embodiment in that: no short-circuiting plate 44 is arranged between the two grid groups 41, one arc extinguishing grid 411 in each grid group 41 away from the arc inlet 401 is used as a tail grid, and the tail grids in the two grid groups 41 are connected to achieve equipotential short-circuiting.

[0102] Preferably, one end of each tail grid close to the arc running channel 402 is bent toward the arc inlet 401. Therefore, when the two tail grids are connected to form an arc striking portion which protrudes toward the arc inlet 401, the arc striking portion is of a V-shaped structure for bridging the electric arc.

[0103] A fourth embodiment (not shown) of an arc extinguishing system is provided.

[0104] The arc extinguishing system includes two arc extinguishing covers 42 and two grid groups 41. Each grid group 41 adopts the grid group 41 in the first embodiment. The two grid groups 41 are arranged in the two arc extinguishing covers 42, respectively. Openings are formed in opposite sides of the two arc extinguishing covers 42, respectively. The arc extinguishing groove 410 of each grid group 41 is opposite to the opening. An arc running channel 402 is formed between the two arc extinguishing grooves 410. The two arc extinguishing chambers 40 are intercommunicated through the arc running channel 402 and the openings of the two arc extinguishing covers 42. The two arc extinguishing chambers 40 are intercommunicated through the arc running channel 402 and the openings of the two arc extinguishing covers 42. In this case, the arc running channel 402 is not completely located in the same arc extinguishing cover 42. It should be noted that the opening of each arc extinguishing cover 42 may cooperate with a partition plate in the contact unit or an additional connecting plate, such that the arc extinguishing covers 42 form a "□"-shaped structure. However, an opening is formed in a side of the arc extinguishing cover 42. A side wall of the arc extinguishing cover 42 facing the opening is also provided with a plurality of exhaust holes 423, and every two adjacent exhaust holes 423 are also misaligned against each other.

[0105] A short-circuiting plate 44 which is the same as that in the first embodiment is also arranged in the arc running channel 402. One ends of the two grid groups 41 away from the air inlet 401 are equipotentially short-circuited through the short-circuiting plate 44. In this case, the arc extinguishing system includes two arc extinguishing chambers 40. The short-circuiting plate 44 is arranged between the openings of the two arc extinguishing covers 42. The short-circuiting plate 44 may have the same structure as that in the first embodiment. Two pins 441 of the short-circuiting plate 44 preferably pass through each opening, so that each pin 441 is spaced opposite to one end of one grid group 41 away from the arc inlet 401. The arc striking plate 442 of the short-circuiting plate 44 is located between the two openings, and the notch in the arc striking plate 442 may communicate the two arc extinguishing covers 42.

[0106] Alternatively, the arc running channel 402 is also provided with a connecting arc extinguishing chamber. A connecting grid group which is the same as that in the second embodiment is arranged in the connecting arc extinguishing chamber. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this case, the arc extinguishing system includes two arc extinguishing chambers 40 and a connecting arc extinguishing chamber.

[0107] Of course, two arc extinguishing covers 42 may also be adopted in the third embodiment. In this case, one end of at least one tail grid may pass through the opening of the arc extinguishing cover 42, thereby forming an arc striking portion in the arc running channel 402.

[0108] In this embodiment, the arc extinguishing system further includes a pair of magnetic conduction plates 43, wherein the magnetic conduction plates 43 are arranged outside the two arc extinguishing covers 42, and a projection of the magnetic conduction plates 43 covers the arc running channel 402. Each magnetic conduction plate 43 may also of a rectangular structure. Preferably, magnetic conduction plate mounting grooves 4251 are formed in outer side walls of the two arc extinguishing covers 42, respectively. A fastening boss 4252 is arranged at the bottom of each magnetic conduction plate mounting groove 4251. The fastening boss 4252 is in limiting fit with the fastening groove 431 of the magnetic conduction plate 43, and its specific position is adjusted according to actual needs. Of course, the magnetic conduction plates 43 and the arc extinguishing cover 42 may also be cooperated in other ways.

[0109] As shown in FIGS. 32 and 33, a length direction of the shell 5 is taken as the first direction, a width direction of the shell 5 is taken as the second direction, a thickness direction of the shell 5 is taken as the third direction, and the first, second and third directions are perpendicular to each other.

[0110] In the embodiment of the above arc extinguishing system, as shown in FIGS. 1-5, 32 and 33, each arc extinguishing system further includes two buffer areas 45. In the second direction, the two buffer areas 45 are located on both sides of the arc extinguishing cover 42, and each buffer area 45 is opposite to the exhaust holes 423 of the arc extinguishing cover 42. A plurality of upright columns 451 opposite to the exhaust holes 423 are arranged in the buffer areas 45 in the third direction. High-temperature exhaust gas discharged from the exhaust holes 423 is buffered by the plurality of upright columns 451 and does not need to be discharged from the shell 5. It is unnecessary to form an additional exhaust port in the shell 5 to avoid the discharge of the high-temperature gas from affecting its safety in use.

[0111] Preferably, the plurality of upright columns 451 are arranged in two rows. The plurality of upright columns 451 in each row are arranged equidistantly along the first direction. The upright columns 451 in the adjacent two rows are misaligned against each other, such that a buffering effect can be further improved within a limited space, which is conducive to reducing the area of the buffer areas 45. Further, baffles 52 are also arranged around the arc extinguishing chamber 40. The baffles 52 are spaced opposite to the exhaust holes 423 of the arc extinguishing chamber 40, so that the space of the shell 5 between the baffles 52 and the exhaust holes 423 forms the buffer area 45. The baffles 52 and the upright columns 451 are arranged together on the bottom wall of the shell 5 in a protruding manner. Preferably, a protruding height of the baffles 52 is greater than a protruding height of the upright columns 451, so as to avoid the high-temperature exhaust gas from overflowing from the buffer areas 45 to a gas space in the shell 5, so that the upright columns 451 are fully utilized, thereby reducing the impact on other components in the shell 5.

[0112] It should be explained that, in the description of the present invention, the terms such as "up", "down", "left", "right", "inner" and "outer" indicating the directional or positional relations on the basis of the directional or positional relations shown in the drawings are only used for conveniently describing the present invention and simplifying the description, not indicate or imply that the referred devices or elements must have a specific orientation and be configured and operated in a specific direction; therefore, they cannot be construed as a limitation on the present invention.

[0113] We have made further detailed description of the present invention mentioned above in combination with specific preferred embodiments, but it is not deemed that the specific embodiments of the present invention is only limited to these descriptions. A person skilled in the art can also, without departing from the concept of the present invention, make several simple deductions or substitutions, which all be deemed to fall within the protection scope of the present invention.

Examples

first embodiment

[0083]an arc extinguishing system is provided in conjunction with FIGS. 1, and 23-31.

[0084]As shown in FIGS. 23-31, the arc extinguishing system includes an arc extinguishing cover 42, two grid groups 41, a short-circuiting plate 44, and a pair of magnetic conduction plates 43. An arc inlet 401 is formed in one end of the arc extinguishing cover 42 and used to introduce the electric arc into the arc extinguishing system in cooperation with the contact mechanism a. The two grid groups 41 are spaced oppositely and arranged on one side of the arc inlet 401. A spacing between the two grid groups 41, which is used as the arc running channel 402, is communicated with the arc inlet 401. The short-circuiting plate 44 is arranged at an end of the arc running channel 402 away from the arc inlet 401. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially connected through the short-circuiting plate 44. A pair of magnetic conduction plates 43 are spaced, and the arc ...

second embodiment

[0106]Alternatively, the arc running channel 402 is also provided with a connecting arc extinguishing chamber. A connecting grid group which is the same as that in the second embodiment is arranged in the connecting arc extinguishing chamber. One ends of the two grid groups 41 away from the arc inlet 401 are equipotentially short-circuited through the connecting grid group. In this case, the arc extinguishing system includes two arc extinguishing chambers 40 and a connecting arc extinguishing chamber.

third embodiment

[0107]Of course, two arc extinguishing covers 42 may also be adopted in the In this case, one end of at least one tail grid may pass through the opening of the arc extinguishing cover 42, thereby forming an arc striking portion in the arc running channel 402.

[0108]In this embodiment, the arc extinguishing system further includes a pair of magnetic conduction plates 43, wherein the magnetic conduction plates 43 are arranged outside the two arc extinguishing covers 42, and a projection of the magnetic conduction plates 43 covers the arc running channel 402. Each magnetic conduction plate 43 may also of a rectangular structure. Preferably, magnetic conduction plate mounting grooves 4251 are formed in outer side walls of the two arc extinguishing covers 42, respectively. A fastening boss 4252 is arranged at the bottom of each magnetic conduction plate mounting groove 4251. The fastening boss 4252 is in limiting fit with the fastening groove 431 of the magnetic conduction plate 43, and ...

Claims

1. A contact unit, comprising a shell (5) and a contact mechanism (a) arranged in the shell (5), wherein the contact mechanism (a) comprises a pair of static contact assemblies (2) and a moving contact assembly (1); each stationary contact assembly (2) comprises a stationary contact portion (21); arc extinguishing systems are arranged on both sides of the contact mechanism (a); each arc extinguishing system comprises an arc extinguishing cover (42); one end of the arc extinguishing cover (42) is used as an arc inlet (401); and the contact mechanism (a) further comprises a housing (3); an accommodating cavity of the housing (3) is provided with two opposing openings; each opening is connected to one arc inlet (401); the moving contact assembly (1) and the stationary contact portions (21) are assembled in the accommodating cavity; the moving contact assembly (1) is located between a pair of stationary contact portions (21); and the contact mechanism (a) and the arc extinguishing systems on both sides jointly form a relatively closed space.

2. The contact unit according to claim 1, wherein the arc extinguishing cover (42) is open at both ends, one open end is used as the arc inlet (401), and the other open end is abutted against and closed by the shell (5); or the arc extinguishing cover (42) is open at one end and closed at the other end, and the open end is used as the arc inlet (401).

3. The contact unit according to claim 1, wherein the moving contact assembly (1) comprises a rotating shaft (11) and a moving contact bridge (12) arranged along a radial direction of the rotating shaft (11); the rotating shaft (11) rotates between a pair of stationary contact portions (21); both ends of the moving contact bridge (12) are used as moving contact portions (120) which cooperate with the stationary contact portions (21); and the moving contact assembly (1) cooperates with the accommodating cavity to block two openings from being communicated with each other.

4. The contact unit according to claim 3, wherein a circumferential side wall of the rotating shaft (11) is provided with two opening limiting portions (115) in a protruding manner; two opening barrier portions (32) are arranged in the accommodating cavity; the opening barrier portions (32) are located on a rotation trajectory of the opening limiting portions (115); each opening limiting portion (115) is adjacent to one moving contact portion (120); when the rotating shaft (11) rotates to an opening position, the opening limiting portions (115) are in limiting fit with the opening barrier portions (32); and the rotating shaft (11), the two opening limiting portions (115) and the two opening barrier portions (32) block two openings from being communicated with each other.

5. The contact unit according to claim 4, wherein one stationary contact portion (21) and one opening barrier portion (32) are located on both sides of the same opening of the housing (3); one moving contact portion (120) and one opening limiting portion (115) jointly rotate between one stationary contact portion (21) and one opening barrier portion (32); and the opening limiting portion (115) is located on a side of the moving contact portion (120) away from the stationary contact portion (21).

6. The contact unit according to claim 4, wherein the housing (3) is of an integrated structure; alternatively, the housing (3) comprises two plate bodies (301) which are spaced oppositely; the two plate bodies (301) are encircled to form a hollow cavity body which is open at both ends; a hollow part of the hollow cavity body is used as the accommodating cavity; splicing structures which cooperate with each other are arranged between the two plate bodies (301); and the splicing structures enable the two plate bodies (301) to form an integral body that can be split in a pluggable manner.

7. The contact unit according to claim 6, wherein the housing (3) comprises two plate bodies (301) which are spaced oppositely; extensions (304) are arranged on the edges of both sides of each plate body (301); the extensions (304) on the same sides of the two plate bodies (301) cooperate with each other to form connecting walls (303) of the housing (3); each connecting wall (303) is provided with an assembling groove (31) and one opening barrier portion (32); and the middle parts of the two plate bodies (301) are used as a pair of supporting walls (302).

8. The contact unit according to claim 2, wherein the arc extinguishing system further comprises a buffer area (45); the arc extinguishing cover (42) is open at both ends; one open end of the arc extinguishing cover (42) is used as the arc inlet (401); a side wall of the arc extinguishing cover (42) adjacent to the arc inlet (401) is provided with a plurality of exhaust holes (423); the arc inlet (401) is communicated with the contact mechanism (a) in a first direction of the shell (5); the buffer area (45) and the arc extinguishing cover (42) are arranged along a second direction of the shell (5); the buffer area (45) is joined with the exhaust holes (423); and the first direction is perpendicular to the second direction.

9. The contact unit according to claim 8, wherein each arc extinguishing system comprises two buffer areas (45); in the second direction, the two buffer areas (45) are located on both sides of the arc extinguishing cover (42); each buffer area (45) is provided with a plurality of upright columns (451), which are opposite to the exhaust holes (423), along a third direction; and the third direction is perpendicular to the first direction and the second direction, respectively.

10. The contact unit according to claim 9, wherein baffles (52) are also arranged around the arc extinguishing chamber (40); the baffles (52) are spaced opposite to the exhaust holes (423) of an arc extinguishing chamber (40), so that a space of the housing (5) between the baffle (52) and the exhaust hole (423) forms the buffer area (45); the plurality of upright columns (451) are arranged in at least two rows; the plurality of upright columns (451) in each row are arranged equidistantly in the first direction; and the upright columns (451) in adjacent rows are misaligned against each other.

11. The contact unit according to claim 9, wherein each arc extinguishing system comprises an arc extinguishing chamber (40), the arc extinguishing chamber (40) comprises an arc extinguishing cover (42) and two grid groups (41) which are spaced within the same arc extinguishing cover (42), and an arc running channel (402) which is communicated with the arc inlet (401) is arranged between the two grid groups (41); alternatively, the arc extinguishing system comprises two arc extinguishing chambers (40), each arc extinguishing chamber comprises an arc extinguishing cover (42) and a grid group (41) arranged within the arc extinguishing cover (42), an opening is formed in a side of each arc extinguishing cover (42) adjacent to the arc inlet (401), openings of the two arc extinguishing covers (42) are opposite each other, an arc extinguishing groove (410) of each grid group (41) is communicated with the arc inlet (401), the arc extinguishing groove (410) of each grid group (41) is opposite to the opening, and a spacing between the two grid groups (41) forms the arc running channel (402) which is communicated with the arc inlet (401).

12. The contact unit according to claim 11, wherein each arc extinguishing system further comprises a short-circuiting plate (44); the short-circuiting plate (44) is arranged at an end of the arc running channel (402) away from the arc inlet (401); the short-circuiting plate (44) comprises two pins (441) and an arc striking plate (442); the two pins (441) extend toward one ends of the two grid groups (41) away from the arc inlet (401) respectively, so that an electric clearance between one ends of the two grid groups (41) away from the arc inlet (401) is less than a minimum physical distance between the two grid groups (41); and the arc striking plate (442) extends along a center line of the arc running channel (402) toward a direction close to the arc inlet (401).

13. The contact unit according to claim 11, wherein one arc extinguishing grid in each grid group (41) away from the arc inlet (401) is a tail grid, the tail grids in the two grid groups (41) are connected, and the tail grids in the two grid groups (41) protrude toward the arc inlet (401) to form an arc striking portion for bridging electric arcs; or a connecting grid group is arranged at an end of the arc running channel (402) away from the arc inlet (401), the connecting grid group comprises a plurality of connecting grids which are spaced, and the plurality of connecting grids are arranged along a straight line, an arc line or a fold line connected between the two connecting grid groups (41).

14. The contact unit according to claim 11, wherein each arc extinguishing system further comprises at least two magnetic conduction plates (43) which are spaced, each magnetic conduction plate (43) is arranged outside the arc extinguishing cover (42), the arc running channel (402) is located between the at least two magnetic conduction plates (43), and a magnetic field is formed by the magnetic conduction plates (43) in the arc running channel (402).

15. A rotary isolation switch, comprising an operating module and a contact module, wherein the contact module comprises at least one contact unit according to any one of claims 1 to 14, and the at least one contact unit is driven by an operating mechanism of the operating module for opening and closing.

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