A permanent magnet arc extinguishing non-polarity high voltage and high current DC contactor

Abstract

The present invention discloses a permanent magnet arc extinguishing non-polarity high-voltage and high-current DC contactor, comprising an arc extinguishing chamber, a moving contact, a base assembly and an electromagnetic driving mechanism, the arc extinguishing chamber base assembly, the electromagnetic driving mechanism is installed below the base assembly, the arc extinguishing chamber comprises two permanent magnets and a magnetic conductive block and a magnetic conductive pole plate, the two permanent magnets are adsorbed at both ends of the magnetic conductive block, the two magnetic conductive pole plates are seamlessly adsorbed on the outside of the two permanent magnets, the permanent magnet, the magnetic conductive block and the magnetic conductive pole plate are built in the middle of the arc extinguishing chamber, and a constant magnetic field parallel to the horizontal direction of the moving contact is formed at both ends of the moving contact. The present invention does not have the danger of critical current, the magnetic field is more efficiently utilized, and the arc blowing effect is more significant; on the basis of ensuring that the product can open and close the circuit without polarity, the breaking capacity of the product is greatly improved, the service life of the product is guaranteed, and the electromagnet can generate lower heat when the product is running for a long time in the holding stage, reduce the aging speed of plastic components, and reduce the generation of useless work.

Description

Technical Field

[0001] The invention relates to a low-voltage electrical appliance switch, in particular to a permanent magnet arc-extinguishing non-polarity high-voltage and high-current DC contactor. Background Art

[0002] Compared with alternating current, direct current does not have a natural zero crossing point. The DC arc generated when cutting off the direct current cannot be extinguished without the help of external force. The external force usually uses magnetic blowing to extinguish the arc. The magnetic blowing forms of conventional DC contactors are generally divided into permanent magnet magnetic blowing and electromagnetic coil magnetic blowing. Among them, permanent magnet magnetic blowing uses permanent magnets to provide a stable magnetic field with constant strength and direction. The structure often designs the direction of the magnetic field to be perpendicular to the direction of the moving contact, so that the arc can be blown to the direction of the arc extinguishing chamber. However, once the reverse current appears when the contactor is disconnected, this magnetic blowing force will blow the arc to the opposite direction of the arc extinguishing chamber, which is the internal square of the product. direction, resulting in a fault in which the arc cannot be extinguished; and the electromagnetic coil magnetic blowing uses the electromagnetic coil to provide an unstable magnetic field. The magnetic field strength is proportional to the current flowing through the electromagnetic coil, and the direction of the magnetic field changes with the direction of the current flowing through the electromagnetic coil. Therefore, the electromagnetic coil is used to provide a magnetic blowing magnetic field, which can be designed to always keep the direction of the magnetic blowing magnetic field blowing the arc to the arc extinguishing chamber. However, when the current flowing through the electromagnetic coil is small, the magnetic field strength will also be very weak, resulting in insufficient arc blowing force, which greatly prolongs the arc extinguishing time and is prone to critical current phenomenon. In addition, the electromagnetic coil solution has the disadvantages of difficult processing technology, large size, and high cost compared with the permanent magnet solution.

[0003] Some of the current DC contactor products use permanent magnet magnetic blowing for non-polarity arc extinguishing, such as the "DC contactor with additional switching capacity for AC loads and polarity opposite to the preferred current direction" described in invention ZL201510150795.9. When a reverse current flows through the product, an "auxiliary arc extinguishing device" arranged between the two static contacts is used to extinguish the arc blowing into the product. However, due to limited structural space, the arc extinguishing capacity of the "auxiliary arc extinguishing device" is much smaller than that of the preferred current arc extinguishing device, so its reverse current breaking capacity is much smaller than the forward breaking capacity, and it cannot be used as the optimal choice for non-polarity DC contactors. For example, the "switch device with permanent magnet arc extinguishing" described in invention ZL201610042594.1 has a total of 4 arc extinguishing channels designed in the arc extinguishing chamber similar to the structure of the present invention, but the direction of the channel is kept horizontally parallel to the direction of the moving contact. The permanent magnet establishes a "blow magnetic field" at the contact position through the magnetic conductive pole plate. When the arc is generated, it is affected by the "blow magnetic field" and is blown to the diagonal arc extinguishing channels respectively. When the current direction changes, the arc is blown to another set of diagonal arc extinguishing channels. However, due to the difference between the arc extinguishing channel and the moving contact, the arc is blown to the diagonal arc extinguishing channel. Due to the positional relationship, the permanent magnet can only establish a "biased blowing magnetic field" but cannot establish a "direct blowing magnetic field". In comparison, the "biased blowing magnetic field" needs to twist the arc 90° before it can enter the arc extinguishing channel when the arc is generated, while the "direct blowing magnetic field" can directly blow the arc into the arc extinguishing channel when the arc is generated. Therefore, the design of the "biased blowing magnetic field" reduces the utilization rate of the permanent magnet. At the same time, when the arc is deflected by the "biased blowing magnetic field", the arc diameter will increase rapidly, the thermal ionization phenomenon will intensify, and the arc energy will also increase accordingly, which increases the difficulty of subsequent arc extinguishing. Summary of the invention

[0004] In view of the shortcomings of high-voltage and high-current DC contactors in the prior art, such as poor breaking capacity and difficulty in arc extinguishing, the technical problem to be solved by the present invention is to provide a permanent magnet arc extinguishing non-polarity high-voltage and high-current DC contactor which can improve the breaking capacity, extinguish arc quickly and increase the service life.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] The present invention provides a permanent magnet arc extinguishing non-polarity high-voltage and high-current DC contactor, comprising an arc extinguishing chamber, a moving contact, a base assembly and an electromagnetic driving mechanism. The arc extinguishing chamber is on the base assembly, and the electromagnetic driving mechanism is installed below the base assembly. The arc extinguishing chamber comprises two permanent magnets, a magnetic conductive block and a magnetic conductive pole plate. The two permanent magnets are adsorbed on both ends of the magnetic conductive block, and the two magnetic conductive pole plates are seamlessly adsorbed on the outside of the two permanent magnets respectively. The permanent magnet, the magnetic conductive block and the magnetic conductive pole plate are jointly built in the middle of the arc extinguishing chamber, and a constant magnetic field parallel to the horizontal direction of the moving contact is formed at both ends of the moving contact.

[0007] The arc extinguishing chamber includes an arc-isolating lining plate, a labyrinth lining plate and an arc-extinguishing grid. Eight arc-isolating lining plates are installed in four independent spaces in the arc-extinguishing chamber in groups of two each. The two arc-isolating lining plates in each group are installed in a symmetrical form and form two parts, namely, a gathering space and a narrow gap space. The gathering space presents an acute angle toward the moving contact, and the narrow gap space presents a narrow gap channel extending to the inner wall of the arc-extinguishing chamber. Four labyrinth lining plates are installed in four independent spaces in the arc-extinguishing chamber and are placed on the upper part of each group of arc-isolating lining plates. The arc-extinguishing grids include long arc-extinguishing grids, medium arc-extinguishing grids and short arc-extinguishing grids, wherein four long arc-extinguishing grids are respectively placed in the outermost partitions of the four labyrinth lining plates, four medium arc-extinguishing grids are respectively placed in the innermost partitions of the four labyrinth lining plates, and multiple short arc-extinguishing grids are evenly divided and placed in the middle partitions of the four labyrinth lining plates.

[0008] The arc extinguishing chamber is also provided with an arc striking plate and an insulating block. The arc striking plate is fixedly installed in the middle position inside the arc extinguishing chamber, and the four arc striking angles of the arc striking plate point to the lower end of the middle arc extinguishing grid; the insulating block is installed in the middle position on both sides of the arc extinguishing chamber and the lower end of the magnetic conductive pole plate.

[0009] The base assembly has a plastic base and two sets of static contact assemblies. The two sets of static contact assemblies include four arc-striking plates and two static contacts. The four arc-striking plates are grouped in two pieces. One end of each set of arc-striking plates is seamlessly fastened to both sides of the static contacts, and the other end extends to the inner wall of the arc extinguishing chamber. Each static contact includes a contact plate and a static silver contact. One end of the contact plate has a rectangular protrusion structure, and the static silver contact is welded above the rectangular protrusion structure of the contactor.

[0010] The present invention has the following beneficial effects and advantages:

[0011] 1. The present invention utilizes permanent magnet magnetic blowing technology to extinguish arcs and establish a stable direct blowing magnetic field. There is no risk of critical current, and the magnetic field is more efficiently utilized, and the arc blowing effect is more significant. At the same time, the permanent magnets that establish the permanent magnetic field are seamlessly adsorbed on both ends of the magnetizer, which reduces the use of permanent magnet materials while ensuring the magnetic field strength requirements.

[0012] 2. The arc extinguishing chamber of the present invention is provided with 4 independent arc extinguishing spaces. When the contacts break the circuit and an arc is generated, the arc between the moving and static contacts is blown to two corresponding arc extinguishing spaces by the permanent magnet direct blowing magnetic field. In the arc extinguishing space, the deionization process is completed in the form of a combination of various arc extinguishing methods such as narrow gaps, mazes, and arc extinguishing grids. This greatly improves the breaking capacity of the product while ensuring that the product can break the circuit without polarity.

[0013] 3. The structural design of the arc-starting sheet, arc-starting plate and contact plate protrusions of the present invention can enable the arc to quickly leave the contact surface under the action of the permanent magnet direct blowing magnetic field in the initial stage, greatly reducing the residence time of the arc on the contact surface, that is, reducing the ablation of the contacts, reducing losses, and ensuring the service life of the product.

[0014] 4. The design of the drive controller inside the electromagnet of the present invention allows the product to enjoy higher power during the startup phase while being in a lower power working state during the maintenance phase, which satisfies the need to overcome the larger reaction force of the contact spring and the reset spring during the product startup phase, and can also enable the electromagnet to generate lower heat when the product runs for a long time during the maintenance phase, thereby reducing the aging speed of plastic components and the generation of useless work. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is an overall cross-sectional view (partial cross-sectional view) of the permanent magnet arc extinguishing non-polarity high-voltage and high-current DC contactor of the present invention;

[0016] Figure 2 It is a cross-sectional view (cross-sectional side view) of the arc extinguishing chamber in the present invention;

[0017] Figure 3 It is a cross-sectional view (cross-sectional longitudinal view) of the arc extinguishing chamber in the present invention;

[0018] Figure 4 It is an oblique view of the moving contact in the present invention;

[0019] Figure 5 is an oblique view of the base assembly of the present invention;

[0020] Figure 6 An oblique view of the stationary contact assembly of the present invention;

[0021] Figure 7 An oblique view of a static contact in the present invention;

[0022] Figure 8 is an oblique view of the electromagnetic drive mechanism of the present invention;

[0023] Fig. 9 The diagram is a moving path diagram of the arc under the action of the direct blowing magnetic field when the bidirectional current is interrupted in the present invention.

[0024] In the figure: 1 is the contactor as a whole, 2 is the arc extinguishing chamber, 3 is the moving contact, 4 is the base assembly, 5 is the electromagnetic drive mechanism; 2 is the arc extinguishing chamber, 201 is the permanent magnet, 202 is the magnetic conductive block, 203 is the magnetic conductive pole plate, 204 is the arc isolation lining plate, 205 is the labyrinth lining plate, 206 is the long arc extinguishing grid, 207 is the middle arc extinguishing grid, 208 is the short arc extinguishing grid, 209 is the arc starting plate, 210 is the insulating block , 3 is the moving contact, 301 is the moving contact bridge, 302 is the moving contact contact; 4 is the base assembly, 401 is the plastic base, 402 is the static contact assembly, 40201 is the arc-starting plate, 40202 is the static contact; 4020201 is the contact plate, 4020202 is the static silver contact; 5 is the electromagnetic drive mechanism, 501 is the electromagnet, 50101 is the armature core, and 502 is the drive controller. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] like Figures 1 to 3 As shown, a permanent magnet arc extinguishing non-polarity high-voltage and high-current DC contactor of the present invention comprises an arc extinguishing chamber 2, a moving contact 3, a base assembly 4 and an electromagnetic drive mechanism 5. The arc extinguishing chamber 2 is on the base assembly 4, and the electromagnetic drive mechanism 5 is installed below the base assembly 4. The arc extinguishing chamber 2 comprises two permanent magnets 201, a magnetic conductive block 202, and a magnetic conductive pole plate 203. The two permanent magnets 201 are adsorbed on both ends of the magnetic conductive block 202, and the two magnetic conductive pole plates 203 are seamlessly adsorbed on the outside of the two permanent magnets 201 respectively. The permanent magnet 201, the magnetic conductive block 202, and the magnetic conductive pole plate 203 are jointly built in the middle of the arc extinguishing chamber 2, and a constant magnetic field parallel to the horizontal direction of the moving contact 3 is formed at both ends of the moving contact 3.

[0027] like Figure 1 As shown, the base assembly 4 is installed above the electromagnetic drive mechanism 5, and the two are fastened and installed by screws. The moving contact 3 is installed on the armature core 50101 (see Figure 8 ), the arc extinguishing chamber 2 is installed above the base assembly 4, and the two are fastened together by screws.

[0028] like Figures 2-3As shown, the arc extinguishing chamber 2 includes an arc-isolating lining plate 204, a labyrinth lining plate 205 and an arc-extinguishing grid. Eight arc-isolating lining plates 204 are grouped into two and are installed in four independent spaces in the arc extinguishing chamber 2. The two arc-isolating lining plates in each group are installed in a symmetrical form to form a gathering space and a narrow gap space. The gathering space presents an acute angle toward the moving contact 3, and the narrow gap space presents a narrow gap channel extending to the inner wall of the arc extinguishing chamber 2. The four labyrinth lining plates 205 are installed in the arc extinguishing chamber 2. The four independent spaces in the chamber 2 are placed on the top of each set of arc-extinguishing lining plates 204; the arc-extinguishing grids include long arc-extinguishing grids 206, medium arc-extinguishing grids 207 and short arc-extinguishing grids 208, wherein the four long arc-extinguishing grids 206 are respectively placed in the outermost partitions of the four labyrinth lining plates 205, the four medium arc-extinguishing grids 207 are respectively placed in the innermost partitions of the four labyrinth lining plates 205, and the 56 short arc-extinguishing grids 208 are equally divided and placed in the middle partitions of the four labyrinth lining plates 205. An arc-striking plate 209 and an insulating block 210 are also provided. The arc-striking plate 209 is fixedly installed in the middle position inside the arc-extinguishing chamber 2, and the four arc-striking angles of the arc-striking plate 209 point to the lower end in the direction of the middle arc-extinguishing grid 207; the insulating block 210 is installed in the middle position on both sides of the arc-extinguishing chamber and the lower end of the magnetic pole plate 203 to isolate the magnetic pole plate 203 from the contact plate 4020101 on the base assembly 4.

[0029] In this embodiment, the arc extinguishing chamber 2 has 4 permanent magnets 201, 2 magnetic conductive blocks 202, 2 magnetic conductive pole plates 203, 8 arc isolation liners 204, 4 labyrinth liners 205, 4 copper long arc extinguishing grids 206, 4 copper medium arc extinguishing grids 207, 56 copper short arc extinguishing grids 208, 1 copper arc starting plate 209 and 2 insulating blocks 210. The 4 permanent magnets 201 are seamlessly adsorbed on both ends of the magnetic conductive blocks 202 with different poles, and the 2 magnetic conductive pole plates 203 are seamlessly adsorbed on the other end of the permanent magnets 201 respectively. The permanent magnets 201, the magnetic conductive blocks 202, and the magnetic conductive pole plates 203 are jointly built in the middle of the arc extinguishing chamber 2, and a constant magnetic field parallel to the horizontal direction of the moving contact 3 is formed at both ends of the moving contact 3. The four long arc-extinguishing grids 206 are respectively placed in the outermost partitions of the four labyrinth linings 205, the four medium arc-extinguishing grids 207 are respectively placed in the innermost partitions of the four labyrinth linings 205, and the 56 short arc-extinguishing grids 208 are equally placed in the middle partitions of the four labyrinth linings 205. The arc-starting plate 209 is fastened to the middle position inside the arc-extinguishing chamber 2 with screws, and the insulating block 210 is installed in the middle position of both sides of the arc-extinguishing chamber, that is, the lower end of the magnetic conductive pole plate 203, to separate the magnetic conductive pole plate 203 from the contact plate 4020101.

[0030] like Figure 4 As shown, the moving contact 3 includes a moving contact bridge 301 and two moving contact points 302 , and the two moving contact points 302 are respectively welded to the lower parts of both ends of the moving contact bridge 30101 .

[0031] like Figure 5 As shown, the base assembly 4 has a plastic base 401 and two sets of stationary contact assemblies 402 .

[0032] like Figure 6 As shown, two groups of stationary contact assemblies 402 include four arc-striking plates 40201 and two stationary contacts 40202. The four arc-striking plates 40201 form a group of two. One end of each group of arc-striking plates 40201 is seamlessly fastened to both sides of the stationary contact 40202, and the other end extends to the inner wall of the arc extinguishing chamber 2.

[0033] like Figure 7 As shown, each static contact 40202 includes a contact plate 4020201 and a static silver contact 4020202. One end of the contact plate 4020201 has a rectangular protrusion structure, and the static silver contact 4020202 is welded above the rectangular protrusion structure of the contactor 4020201.

[0034] like Figure 8 As shown, the electromagnetic drive mechanism 5 includes an electromagnet 501 and a drive controller 502. The drive controller 502 is located below the electromagnet 501 and has a built-in delayed conversion circuit to delay the conversion of the electromagnet from a high-power starting state to a low-power holding state. The electromagnet 501 has an armature core 50101, which is located in the middle of the electromagnet 501 and extends outward into the arc extinguishing chamber 2.

[0035] The working process and principle of the present invention are as follows:

[0036] In the present invention, four independent arc extinguishing spaces are provided in the arc extinguishing chamber 2. When the contacts break the circuit and generate an arc, the arc between the moving and static contacts is blown to two corresponding arc extinguishing spaces by the permanent magnetic direct blowing magnetic field constructed by the permanent magnet 201, the magnetic conductive block 202 and the magnetic conductive pole plate 203. In the arc extinguishing space, the arc deionization process is completed in the form of a combination of a narrow gap arc extinguishing formed by the arc isolation lining plate 204, a labyrinth arc extinguishing formed by the labyrinth lining plate 205, and a plurality of grid arc extinguishing modes formed by the long arc extinguishing grid 206, the middle arc extinguishing grid 207 and the short arc extinguishing grid 208. When a current in the opposite direction appears in the circuit, the arc is blown to the other two corresponding arc extinguishing spaces (such as Fig. 9As shown), the above-mentioned deionization process is completed in the other two corresponding arc extinguishing spaces, thereby greatly improving the breaking capacity of the product on the basis of ensuring that the product can break the circuit without polarity; at the same time, in order to ensure that the permanent magnet direct blowing magnetic field can be as close to the arc generation position as possible, the magnetic pole plate 203 is installed near the contact plate 4020201 and insulated by the insulating block 210; in the initial stage of arc generation, the arc at the moving contact point 302 is quickly blown to the arc striking piece 209 by the permanent magnet direct blowing magnetic field, and the arc at the static silver contact 4020202 is quickly blown to the arc striking plate 40201. The raised structural design of the contact plate 4020201 can make the arc in the middle position of the entire arc extinguishing chamber space, and the strong hot air pressure generated by the arc will spread evenly to the surroundings, and will not cause local air pressure. The arc blowing path is blocked due to being too high. The above three designs can make the arc leave the contact surface quickly in the initial stage, which greatly reduces the residence time of the arc on the contact surface, that is, reduces the ablation of the contacts, reduces losses, and ensures the service life of the product; the design of the drive controller 502 in the electromagnetic drive mechanism 5 can make the product enjoy higher power in the startup stage while being in a lower power working state in the holding stage, that is, it meets the need to overcome the large reaction force of the contact spring and the reset spring in the startup stage of the product, and forms a large suction force in the electromagnet, and pulls the moving contact 3 to move toward the static contact assembly 402 through the armature core 50101, and can also make the electromagnet 501 generate lower heat when the product is running for a long time in the holding stage, thereby reducing the aging rate of the plastic components and the generation of useless work.

Claims

1. A permanent magnet arc extinguishing non-polarity high voltage and high current DC contactor, comprising an arc extinguishing chamber (2), a moving contact (3), a base assembly (4) and an electromagnetic drive mechanism (5), wherein the arc extinguishing chamber (2) is arranged on the base assembly (4), and the electromagnetic drive mechanism (5) is installed below the base assembly (4), characterized in that: The arc extinguishing chamber (2) comprises two permanent magnets (201), a magnetic conductive block (202), and a magnetic conductive pole plate (203); the two permanent magnets (201) are adsorbed on both ends of the magnetic conductive block (202); the two magnetic conductive pole plates (203) are seamlessly adsorbed on the outside of the two permanent magnets (201); the permanent magnets (201), the magnetic conductive block (202), and the magnetic conductive pole plates (203) are jointly built into the middle of the arc extinguishing chamber (2), and a constant magnetic field parallel to the horizontal direction of the moving contact (3) is formed at both ends of the moving contact (3); The arc extinguishing chamber (2) comprises an arc-isolating lining plate (204), a labyrinth lining plate (205) and an arc-extinguishing grid. Eight arc-isolating lining plates (204) are installed in four independent spaces in the arc extinguishing chamber (2) in groups of two. The two arc-isolating lining plates in each group are installed in a symmetrical manner and form two parts, namely, a gathering space and a narrow gap space. The gathering space presents an acute angle toward the moving contact (3), and the narrow gap space presents a narrow gap channel extending to the inner wall of the arc extinguishing chamber (2). Four labyrinth lining plates (205) are installed in four independent spaces in the arc extinguishing chamber (2) and are placed on the upper part of each group of arc-isolating lining plates (204). The base assembly (4) comprises a plastic base (401) and two groups of stationary contact assemblies (402); the two groups of stationary contact assemblies (402) comprise a total of four arc-starting plates (40201) and two stationary contacts (40202); the four arc-starting plates (40201) are grouped in pairs; one end of each group of arc-starting plates (40201) is seamlessly fastened to both sides of the stationary contacts (40202), and the other end extends to the inner wall of the arc extinguishing chamber (2); each stationary contact (40202) comprises a contact plate (4020201) and a static silver contact (4020202); one end of the contact plate (4020201) comprises a rectangular protruding structure; the static silver contact (4020202) is welded above the rectangular protruding structure of the contactor (4020201).

2. The permanent magnet arc extinguishing non-polarity high voltage and high current DC contactor according to claim 1 is characterized in that: The arc-extinguishing grids include long arc-extinguishing grids (206), medium arc-extinguishing grids (207) and short arc-extinguishing grids (208), wherein four long arc-extinguishing grids (206) are respectively placed in the outermost partitions of four labyrinth linings (205), four medium arc-extinguishing grids (207) are respectively placed in the innermost partitions of the four labyrinth linings (205), and a plurality of short arc-extinguishing grids (208) are respectively placed in the middle partitions of the four labyrinth linings (205) in equal numbers.

3. The permanent magnet arc extinguishing non-polarity high voltage and high current DC contactor according to claim 2 is characterized in that: An arc-striking piece (209) and an insulating block (210) are also provided. The arc-striking piece (209) is fixedly mounted in the middle position inside the arc-extinguishing chamber (2), and four arc-striking corners of the arc-striking piece (209) point in the direction of the lower end of the middle arc-extinguishing grid piece (207). The insulating block (210) is mounted in the middle position of both sides of the arc-extinguishing chamber and at the lower end of the magnetic conductive pole plate (203).

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