Electromagnetic contactor with permanent magnetic bidirectional arc extinguishing device and arc extinguishing method thereof

Abstract

The application relates to an electromagnetic contactor with a permanent magnetic bidirectional arc extinguishing device, which comprises a contactor unit, an arc extinguishing unit and a support body; the contactor unit comprises a contactor, a first wiring terminal, a second wiring terminal and a magnetic circuit assembly; the contactor comprises a first static contact head electrically connected with the first wiring terminal, a second static contact head electrically connected with the second wiring terminal and a moving contact head assembly; the moving contact head assembly comprises a first moving contact head and a second moving contact head which are fixed together and electrically connected; the support body is used for connecting and fixing various parts in the contactor unit and the arc extinguishing unit; the arc extinguishing unit comprises an arc extinguishing cover, two parallel and oppositely arranged magnetic guide pole plates, one or more groups of permanent magnetic assemblies and two groups of positive arc extinguishing assemblies and two groups of reverse arc extinguishing assemblies. The application realizes breaking bidirectional direct current and power frequency alternating current, guarantees low cost, convenient maintenance and simple manufacturing, and meets the needs of compact product design.

Description

Technical Field

[0001] The present invention relates to an electromagnetic contactor and an arc extinguishing method thereof, in particular to an electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device and an arc extinguishing method thereof. Background Art

[0002] At present, conventional air arc extinguishing devices are mainly divided into the following types:

[0003] 1. Electromagnetic arc extinguishing device: An electromagnetic coil is set in the arc extinguishing device. When an arc is generated, the electromagnetic coil is first charged to form an electromagnetic field, thereby driving the arc to move.

[0004] Advantages: a) No requirements on the direction of current; b) Can disconnect industrial frequency AC power.

[0005] Disadvantages: a) Low space utilization, resulting in heavy and bulky products; b) There is a critical current (the current cannot be reliably cut off at low currents); c) Since it takes time for the electromagnetic coil to charge and form an electromagnetic field, the arc will stay in the main contact area for a long time, increasing the main contact loss; d) It is expensive and difficult to maintain; e) The manufacturing process is complicated.

[0006] 2. Permanent magnet one-way arc extinguishing device: A permanent magnet is set in the arc extinguishing device to form a permanent magnetic field. When an arc is generated, it will immediately start to move due to the magnetic field force.

[0007] Advantages: a) High space utilization, product weight and volume are greatly reduced, and the contactor structure can be simplified; b) No critical current; c) Since the permanent magnetic field is always present, the arc will quickly leave the main contact area after generation, reducing the main contact loss; d) Relatively low price and easy maintenance; e) Simple manufacturing process.

[0008] Disadvantages: a) There are requirements for the direction of current; b) It cannot disconnect industrial frequency AC power.

[0009] 3. Hybrid arc extinguishing device (electromagnetic + permanent magnet): The arc extinguishing device is equipped with an electromagnetic coil and a permanent magnet. When the main circuit of the contactor is powered off, the permanent magnetic field first drives the arc away from the contact area, and then the electromagnetic field is charged to form an electromagnetic field, which drives the arc into the arc extinguishing cover.

[0010] Advantages: a) No requirements on the direction of current; b) Reduced contact burnout; e) Can disconnect AC power.

[0011] Disadvantages: a) Lower space utilization, resulting in a significant increase in product volume and weight; b) More expensive and more difficult to maintain; c) More complicated manufacturing process.

[0012] Nowadays, with the development of locomotive vehicle technology, more and more users hope to choose a new type of contactor that not only has the above advantages but also eliminates the above disadvantages. SUMMARY

[0013] The present application aims at solving the problems of the prior art, such as the requirement of current direction, incapability of breaking power frequency alternating current, large size, high cost, difficult maintenance and complex manufacturing process, and providing an electromagnetic contactor with permanent magnetic bidirectional arc extinguishing device and an arc extinguishing method thereof.

[0014] The technical solution of the present application is as follows:

[0015] The electromagnetic contactor with permanent magnetic bidirectional arc extinguishing device comprises a contactor unit, an arc extinguishing unit and a bracket body; the contactor unit comprises a contactor, a first wiring terminal, a second wiring terminal and a magnetic circuit assembly; the contactor comprises a first static contact electrically connected with the first wiring terminal, a second static contact electrically connected with the second wiring terminal and a moving contact assembly; the moving contact assembly comprises a first moving contact and a second moving contact fixed together and electrically connected; the first static contact and the first moving contact form a first main contact point; the second static contact and the second moving contact form a second main contact point; the bracket body is used for connecting and fixing the parts in the contactor unit and the arc extinguishing unit; the special feature is that the arc extinguishing unit comprises an arc extinguishing cover, two parallel and oppositely arranged magnetic conductive pole plates, one or more groups of permanent magnetic assemblies and two groups of positive connection arc extinguishing assemblies and two groups of reverse connection arc extinguishing assemblies; the one or more groups of permanent magnetic assemblies are fixed between the two magnetic conductive pole plates; the two groups of positive connection arc extinguishing assemblies and the two groups of reverse connection arc extinguishing assemblies are located in the arc extinguishing cover; the one or more groups of permanent magnetic assemblies form an arc extinguishing magnetic field between the two magnetic conductive pole plates; the permanent magnets of the multiple groups of permanent magnetic assemblies have the same polarity;

[0016] The permanent magnetic assembly comprises a permanent magnet, two magnetic cores coaxially fixed with the permanent magnet and respectively located at two ends of the permanent magnet; the outer ends of the two magnetic cores are fixed with one magnetic conductive pole plate respectively;

[0017] The first group of positive connection arc extinguishing assemblies is arranged on one side of the first static contact and the first moving contact, and the first group of reverse connection arc extinguishing assemblies is arranged on the other side of the first static contact and the first moving contact; the second group of positive connection arc extinguishing assemblies is arranged on the side of the second static contact and the second moving contact away from the first group of positive connection arc extinguishing assemblies, and the second group of reverse connection arc extinguishing assemblies is arranged on the other side of the second static contact and the second moving contact.

[0018] Further, two pairs of small pole plates are further included;

[0019] The permanent magnetic assembly comprises two groups, one group of permanent magnetic assembly comprises a first permanent magnet, a first magnetic core and a second magnetic core, and the other group of permanent magnetic assembly comprises a second permanent magnet, a first magnetic core and a second magnetic core; the two pairs of small pole plates comprise a pair of first small pole plates and a pair of second small pole plates; the magnetic conductive pole plate comprises a first large pole plate and a second large pole plate;

[0020] The two first magnetic cores are fixed together by a first small pole plate and a first large pole plate respectively; and the two second magnetic cores are fixed together by a second small pole plate and a second large pole plate respectively.

[0021] Further, each group of positive-connection arc-extinguishing assembly comprises a positive-connection lower arc-guiding plate, a positive-connection middle arc-guiding plate and a positive-connection upper arc-guiding plate; wherein:

[0022] The first group of positive-connection arc-extinguishing assembly respectively corresponds to a second arc-guiding plate, a fourth arc-guiding plate and a sixth arc-guiding plate; the second arc-guiding plate is located below the first static contact and connected with the first static contact, and the end thereof is downwardly inclined and bent; the fourth arc-guiding plate is located above the first dynamic contact and connected with the first dynamic contact, and the end thereof is upwardly inclined and bent; and the sixth arc-guiding plate is located above the fourth arc-guiding plate and horizontally placed.

[0023] The second group of positive-connection arc-extinguishing assembly respectively corresponds to a seventh arc-guiding plate, a ninth arc-guiding plate and an eleventh arc-guiding plate; the seventh arc-guiding plate is located below the second static contact and connected with the second static contact, and the end thereof is downwardly inclined and bent; the ninth arc-guiding plate is located above the second dynamic contact and connected with the second dynamic contact, and the end thereof is upwardly inclined and bent; and the eleventh arc-guiding plate is located above the ninth arc-guiding plate and horizontally placed.

[0024] Further, each group of negative-connection arc-extinguishing assembly comprises a negative-connection lower arc-guiding plate, a negative-connection middle arc-guiding plate and a negative-connection upper arc-guiding plate; wherein:

[0025] The first group of negative-connection arc-extinguishing assembly respectively corresponds to a first arc-guiding plate, a third arc-guiding plate and a fifth arc-guiding plate; the first arc-guiding plate is located below the first static contact and connected with the first static contact, and the end thereof is downwardly inclined and bent; the third arc-guiding plate is located above the first dynamic contact and connected with the first dynamic contact, and the end thereof is upwardly inclined and bent; and the fifth arc-guiding plate is located above the third arc-guiding plate and horizontally placed.

[0026] The second group of negative-connection arc-extinguishing assembly respectively corresponds to an eighth arc-guiding plate, a tenth arc-guiding plate and a twelfth arc-guiding plate; the eighth arc-guiding plate is located below the second static contact and connected with the second static contact, and the end thereof is downwardly inclined and bent; the tenth arc-guiding plate is located above the second dynamic contact and connected with the second dynamic contact, and the end thereof is upwardly inclined and bent; and the twelfth arc-guiding plate is located above the tenth arc-guiding plate and horizontally placed.

[0027] Further, the fifth arc-guiding plate, the sixth arc-guiding plate, the eleventh arc-guiding plate and the twelfth arc-guiding plate are connected with each other to form a large arc-guiding plate.

[0028] Further, the third arc striking guide plate, the fourth arc striking guide plate, the ninth arc striking guide plate, the tenth arc striking guide plate and the large arc striking plate are spaced apart.

[0029] Further, the third arc striking guide plate, the fourth arc striking guide plate, the ninth arc striking guide plate, the tenth arc striking guide plate have a width smaller than the first arc striking guide plate, the second arc striking guide plate, the seventh arc striking guide plate, the eighth arc striking guide plate and the large arc striking plate.

[0030] Further, the permanent magnet and the magnetic core are both cylindrical.

[0031] An arc extinguishing method of an electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device, which is characterized in that,

[0032] Step one, connecting the first and second terminals to the two ends of the power supply respectively;

[0033] Step two, when the magnetic circuit assembly acts to cause the main circuit of the contactor to be disconnected, causing an electric arc to be generated between the first moving contact and the first stationary contact, and an electric arc to be generated between the second moving contact and the second stationary contact;

[0034] Step three, through the magnetic field force between the two magnetic pole plates, the electric arc moves along the corresponding arc striking guide plate and finally moves into the arc extinguishing cover to complete the arc extinguishing.

[0035] Further, in step one, the power supply is a direct current power supply or an alternating current power supply.

[0036] The beneficial effects of the present application are:

[0037] 1. Regardless of the direction of the current, the electric arc generated by the electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device provided by the present application will always enter the arc extinguishing cover as required by the design and be extinguished.

[0038] 2. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device provided by the present application is suitable for breaking bidirectional direct current and power frequency alternating current.

[0039] 3. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device provided by the present application is more cost-effective. Since the magnetic field of this arc extinguishing system is generated by at least one permanent magnet, the expensive and heavy electromagnetic coil can be completely removed.

[0040] 4. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device provided by the present application has a simple manufacturing process, smaller volume / weight, convenient maintenance and longer life cycle.

[0041] 5. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device provided by the present application uses three groups of arc striking guide plates with different structures, different directions and different lengths, which facilitates the movement of the electric arc. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 is a structural schematic diagram of an electromagnetic contactor embodiment of the present application with a permanent magnetic bidirectional arc extinguishing device (the arc shield, the second small pole plate and the second large pole plate are not shown);

[0043] Figure 2 is a schematic diagram of the arc path when the power is connected in positive of the electromagnetic contactor embodiment of the present application with a permanent magnetic bidirectional arc extinguishing device;

[0044] Figure 3 is a schematic diagram of the arc path when the power is connected in reverse of the electromagnetic contactor embodiment of the present application with a permanent magnetic bidirectional arc extinguishing device.

[0045] Reference signs:

[0046] 11-first static contact, 12-second static contact, 21-first wiring terminal, 22-second wiring terminal, 3-moving contact assembly, 31-first moving contact, 32-second moving contact, 4-magnetic circuit assembly, 51-first permanent magnet, 52-second permanent magnet, 61-first magnetic core, 62-second magnetic core, 71-first small pole plate, 72-second small pole plate, 81-first large pole plate, 82-second large pole plate, 91-first main contact, 92-second main contact, 111-first channel, 112-second channel, 113-third channel, 114-fourth channel, 131-first arc leading guide plate, 132-second arc leading guide plate, 141-third arc leading guide plate, 142-fourth arc leading guide plate, 161-fifth arc leading guide plate, 162-sixth arc leading guide plate, 133-seventh arc leading guide plate, 134-eighth arc leading guide plate, 143-ninth arc leading guide plate, 144-tenth arc leading guide plate, 163-eleventh arc leading guide plate, 164-twelfth arc leading guide plate, 15-large arc leading plate, 17-first magnetic field region, 18-second magnetic field region. DETAILED DESCRIPTION

[0047] Figure 1 is a structural schematic diagram of an electromagnetic contactor embodiment of the present application with a permanent magnetic bidirectional arc extinguishing device (the arc shield, the second small pole plate and the second large pole plate are not shown). It should be noted that, in order to clearly show the structure of the contactor, the shell of the contactor and other structural parts shown in Figure 2 are not shown in Figure 1 . As Figure 1 and Figure 2As shown, the electromagnetic contactor includes a contactor unit, an arc extinguishing unit and a bracket body; the contactor unit includes a contactor, a first wiring terminal 21, a second wiring terminal 22 and a magnetic circuit assembly 4; the contactor includes a first static contact 11 electrically connected with the first wiring terminal 21, a second static contact 12 electrically connected with the second wiring terminal 22 and a moving contact assembly 3; the moving contact assembly 3 includes a first moving contact 31 and a second moving contact 32 fixedly connected and electrically connected together. Wherein, the first static contact 11 and the first moving contact 31 constitute a first main contact point 91; the second static contact 12 and the second moving contact 32 constitute a second main contact point 92. The bracket body is used for connecting and fixing the parts in the contactor unit and the arc extinguishing unit.

[0048] The arc extinguishing unit includes an arc extinguishing cover, two parallel and oppositely arranged magnetic conducting pole plates, one or more groups of permanent magnet assemblies and two groups of positive connection arc extinguishing assemblies and two groups of reverse connection arc extinguishing assemblies; the one or more groups of permanent magnet assemblies are fixed between the two magnetic conducting pole plates; the two groups of positive connection arc extinguishing assemblies and the two groups of reverse connection arc extinguishing assemblies are located in the arc extinguishing cover; the one or more groups of permanent magnet assemblies form an arc extinguishing magnetic field between the two magnetic conducting pole plates; the permanent magnets of the multiple groups of permanent magnet assemblies have the same polarity. The arc extinguishing cover is connected with the bracket body fixedly connecting the contactor unit and the arc extinguishing unit through clamping.

[0049] Wherein, the permanent magnet assembly can include a permanent magnet, two magnetic cores coaxially fixed with the permanent magnet and respectively located at two ends of the permanent magnet. The outer ends of the two magnetic cores are fixed with one magnetic conducting pole plate respectively. As shown in Figure 1 and Figure 2 As shown, the electromagnetic contactor with the permanent magnet bidirectional arc extinguishing device further includes two pairs of small pole plates. The permanent magnet assembly is two groups, wherein one group of permanent magnet assemblies includes a first permanent magnet 51, a first magnetic core 61 and a second magnetic core 62, and the other group of permanent magnet assemblies includes a second permanent magnet 52, a first magnetic core 61 and a second magnetic core 62; the two pairs of small pole plates include a pair of first small pole plates 71 and a pair of second small pole plates 72; the magnetic conducting pole plate includes a first large pole plate 81 and a second large pole plate 82; the first permanent magnet 51 is fixed between the first magnetic core 61 and the second magnetic core 62, and the second permanent magnet 52 is fixed between the first magnetic core 61 and the second magnetic core 62 on the other side; the two first magnetic cores 61 are fastened together through a first small pole plate 71 and a first large pole plate 81 by screws respectively, and the two second magnetic cores 62 are fastened together through a second small pole plate 72 and a second large pole plate 82 by screws respectively. The permanent magnet and the magnetic core are both cylindrical.

[0050] It should be understood that the outer end of the magnetic core can be directly fixed with the large pole plate, or can be fixed with the small pole plate first and then fixed with the large pole plate through the small pole plate; the permanent magnet and the magnetic core can be cylindrical or other shapes, and the present application does not limit this.

[0051] The two permanent magnets have the same polarity, with the north pole located on the side of the first major plate 81 and the south pole located on the side of the second major plate 82. This effectively creates a superposition and reinforcement of the magnetic fields between the first and second major plates, ensuring a strong magnetic field at the first or second main contact. If the polarity were opposite, the magnetic fields between the first and second major plates would cancel each other out, resulting in no magnetic field at the first or second main contact, making it impossible to dispel the arc.

[0052] It should be understood that the N poles of the permanent magnets may also be located on the side of the second large pole plate 82 , and the S poles may also be located on the side of the first large pole plate 81 , and the present invention does not limit this.

[0053] like Figure 1 As shown, the forward arc extinguishing components can be divided into two groups, each group of forward arc extinguishing components includes a forward lower arc-striking guide plate, a forward middle arc-striking guide plate and a forward upper arc-striking guide plate; the reverse arc extinguishing components can also be divided into two groups, each group of reverse arc extinguishing components includes a reverse lower arc-striking guide plate, a reverse middle arc-striking guide plate and a reverse upper arc-striking guide plate.

[0054] The specific position relationship of the two sets of positive arc extinguishing components is as follows:

[0055] The first set of positive arc-extinguishing components is arranged on one side of the first static contact 11 and the first moving contact 31. The first set of positive arc-extinguishing components includes a second arc-striking guide plate 132, a fourth arc-striking guide plate 142, and a sixth arc-striking guide plate 162, respectively. The second arc-striking guide plate 132 is located below and connected to the first static contact 11, with its end bent downward. The fourth arc-striking guide plate 142 is located above and connected to the first moving contact 31, with its end bent upward. The sixth arc-striking guide plate 162 is located above the fourth arc-striking guide plate 142 and is positioned horizontally. The second arc-striking guide plate 132 is associated with the sixth arc-striking guide plate 162; the sixth arc-striking guide plate 162 is associated with the fourth arc-striking guide plate 142; and the fourth arc-striking guide plate 142 is associated with the moving contact assembly 3. The second arc-starting runner 132 , the fourth arc-starting runner 142 , and the sixth arc-starting runner 162 form a set of arc-starting runners that are associated with the channel 112 .

[0056] The second set of positive arc extinguishing assemblies are arranged on the side of the second static contact 12 and the second moving contact 32 away from the first set of positive arc extinguishing assemblies. The second set of positive arc extinguishing assemblies respectively correspond to the seventh arc striking guide plate 133, the ninth arc striking guide plate 143 and the eleventh arc striking guide plate 163. The seventh arc striking guide plate 133 is located below the second static contact 12 and connected with the second static contact 12, and the end thereof is downwardly inclined and bent. The ninth arc striking guide plate 143 is located above the second moving contact 32 and connected with the second moving contact 32, and the end thereof is upwardly inclined and bent. The eleventh arc striking guide plate 163 is located above the ninth arc striking guide plate 143 and horizontally placed. The seventh arc striking guide plate 133 is associated with the eleventh arc striking guide plate 163. The eleventh arc striking guide plate 163 is associated with the ninth arc striking guide plate 143. The ninth arc striking guide plate 143 is associated with the moving contact assembly 3. The seventh arc striking guide plate 133, the ninth arc striking guide plate 143 and the eleventh arc striking guide plate 163 form a set of arc striking guide plates, which are associated with the channel 113.

[0057] The specific positional relationship of the two sets of negative arc extinguishing assemblies is as follows:

[0058] The first set of negative arc extinguishing assemblies are arranged on the other side of the first static contact 11 and the first moving contact 31. The first set of negative arc extinguishing assemblies respectively correspond to the first arc striking guide plate 131, the third arc striking guide plate 141 and the fifth arc striking guide plate 161. The first arc striking guide plate 131 is located below the first static contact 11 and connected with the first static contact 11, and the end thereof is downwardly inclined and bent. The third arc striking guide plate 141 is located above the first moving contact 31 and connected with the first moving contact 31, and the end thereof is upwardly inclined and bent. The fifth arc striking guide plate 161 is located above the third arc striking guide plate 141 and horizontally placed. The first arc striking guide plate 131 is associated with the fifth arc striking guide plate 161. The fifth arc striking guide plate 161 is associated with the third arc striking guide plate 141. The third arc striking guide plate 141 is associated with the moving contact assembly 3. The first arc striking guide plate 131, the third arc striking guide plate 141 and the fifth arc striking guide plate 161 form a set of arc striking guide plates, which are associated with the channel 111.

[0059] The second group of reverse-connection arc-extinguishing assemblies are arranged on the other side of the second static contact 12 and the second moving contact 32. The second group of reverse-connection arc-extinguishing assemblies respectively include an eighth arc striking guide plate 134, a tenth arc striking guide plate 144 and a twelfth arc striking guide plate 164. The eighth arc striking guide plate 134 is arranged below the second static contact 12 and connected with the second static contact 12, and the end of the eighth arc striking guide plate 134 is downwardly and obliquely bent. The tenth arc striking guide plate 144 is arranged above the second moving contact 32 and connected with the second moving contact 32, and the end of the tenth arc striking guide plate 144 is upwardly and obliquely bent. The twelfth arc striking guide plate 164 is arranged above the tenth arc striking guide plate 144 and horizontally placed. The eighth arc striking guide plate 134 is associated with the twelfth arc striking guide plate 164. The twelfth arc striking guide plate 164 is associated with the tenth arc striking guide plate 144. The tenth arc striking guide plate 144 is associated with the moving contact assembly 3. The eighth arc striking guide plate 134, the tenth arc striking guide plate 144 and the twelfth arc striking guide plate 164 form a group of arc striking guide plates, which are associated with the channel 114.

[0060] The fifth arc striking guide plate 161, the sixth arc striking guide plate 162, the eleventh arc striking guide plate 163 and the twelfth arc striking guide plate 164 are connected with each other to form a large arc striking plate 15. There is a gap between the third arc striking guide plate 141, the fourth arc striking guide plate 142, the ninth arc striking guide plate 143, the tenth arc striking guide plate 144 and the large arc striking plate 15. The width of the third arc striking guide plate 141, the fourth arc striking guide plate 142, the ninth arc striking guide plate 143 and the tenth arc striking guide plate 144 is smaller than the width of the first arc striking guide plate 131, the second arc striking guide plate 132, the seventh arc striking guide plate 133, the eighth arc striking guide plate 134 and the large arc striking plate 15.

[0061] The two groups of positive-connection arc-extinguishing assemblies are different sides, the two groups of reverse-connection arc-extinguishing assemblies are different sides, and the positions of the two groups of reverse-connection arc-extinguishing assemblies are centrally symmetrical to the positions of the two groups of positive-connection arc-extinguishing assemblies.

[0062] For the convenience of description and understanding, the present application divides the arc-extinguishing magnetic field into a first magnetic field region 17 and a second magnetic field region 18, wherein the magnetic field lines of the first magnetic field region 17 and the second magnetic field region 18 are in the same direction. The first magnetic field region 17 is further divided into a magnetic field region a and a magnetic field region b, and the second magnetic field region 18 is further divided into a magnetic field region c and a magnetic field region d. The moving direction of the arc depends on the current direction, and the magnetic field drives the arc from the main contact region to the magnetic field region a and the magnetic field region d or the magnetic field region b and the magnetic field region c, and finally enters the arc-extinguishing cover. It should be understood that the present application divides the magnetic field region only for the convenience of description and understanding, and does not make other limitations.

[0063] Principle of the present application:

[0064] In the process of using the contactor, when the main circuit of the contactor is powered off, the arc will be generated between the static contact and the moving contact of the contactor. In order to avoid the contactor from being damaged by the arc with huge energy, the arc must be driven away from the area of the moving contact and the static contact and be extinguished. Therefore, the application provides an electromagnetic contactor with a permanent magnetic bidirectional arc extinguishing device, which has at least one contact and an arc extinguishing device associated with the contact; wherein the arc extinguishing device comprises at least one permanent magnet for generating a permanent magnetic field, which functions to provide a magnetic field force to drive the arc away from the area of the main contact and to the arc extinguishing device when the main circuit of the contactor is powered off. The electromagnetic contactor with the permanent magnetic bidirectional arc extinguishing device provided by the application generates a magnetic field only by the permanent magnet, without the need of an electromagnetic arc extinguishing coil.

[0065] When the main circuit of the contactor is powered on, the coil of the magnetic circuit assembly 4 drives the moving contact assembly 3 to move, the first moving contact 31 approaches and is attached to the first static contact 11, and the second moving contact 32 approaches and is attached to the second static contact 12.

[0066] When the main circuit of the contactor is powered off, the first moving contact 31 is away from the first static contact 11, and the second moving contact 32 is away from the second static contact 12. At this time, the arc is generated between the first moving contact 31 and the first static contact 11, and between the second moving contact 32 and the second static contact 12.

[0067] The application also provides an arc extinguishing method of the electromagnetic contactor with the permanent magnetic bidirectional arc extinguishing device, and the implementation of the arc extinguishing method can be as follows:

[0068] The first case: the wiring terminal of the electromagnetic contactor with the permanent magnetic bidirectional arc extinguishing device is connected to the direct current power supply.

[0069] In this case, the wiring terminal connected to the direct current power supply can have the following two options:

[0070] One possible option: the first wiring terminal 21 is connected to the positive pole of the power supply, and the second wiring terminal 22 is connected to the negative pole of the power supply. Figure 2 is a schematic diagram of the arc direction of the embodiment of the electromagnetic contactor with the permanent magnetic bidirectional arc extinguishing device of the application when the positive pole of the power supply is connected, the cross section of which extends through the middle plane of the first moving contact 31, the second moving contact 32, the first static contact 11 and the second static contact 12 of Figure 1 .

[0071] As shown in Figure 2As shown, when the contactor main circuit is disconnected, the first moving contact 31 and the first stationary contact 11 produce an arc, i.e. the first main contact 91 produces an arc, which is driven by the magnetic field force to move upward into the second channel 112, and the moving direction of the arc is shown by arrow A; the second moving contact 32 and the second stationary contact 12 produce an arc, i.e. the second main contact 92 produces an arc, which is driven by the magnetic field force to move downward along into the third channel 113, and the moving direction of the arc is shown by arrow B.

[0072] The movement of the arc under the action of the magnetic field can be divided into the following two stages:

[0073] The first stage: the arc produced by the first main contact 91 and the arc produced by the second main contact 92 start to move under the action of the magnetic field force respectively. At this time, the current flows from the first wiring terminal 21 to the second wiring terminal 22 through the first stationary contact 11, the first moving contact 31, the moving contact assembly 3, the second moving contact 32 and the second stationary contact 12. This stage lasts until the arcs reach the ends of the fourth arc guide plate 142 and the ninth arc guide plate 143 respectively.

[0074] The second stage: when the arc produced by the first main contact 91 reaches the end of the fourth arc guide plate 142, it spark discharges onto the sixth arc guide plate 162 of the large arc plate 15. When the arc produced by the second main contact 92 reaches the end of the ninth arc guide plate 143, it spark discharges onto the eleventh arc guide plate 163 of the large arc plate 15. At this time, the current flows from the first wiring terminal 21 to the second wiring terminal 22 through the first stationary contact 11, the second arc guide plate 132, the sixth arc guide plate 162, the large arc plate 15, the eleventh arc guide plate 163, the seventh arc guide plate 133 and the second stationary contact 12.

[0075] The arc produced by the first main contact 91 is elongated by the arc guide plate and then passes through the second channel 112, and finally extinguishes in its associated arc extinguishing chamber. The arc produced by the second main contact 92 is elongated by the arc guide plate and then passes through the third channel 113, and finally extinguishes in its associated arc extinguishing chamber.

[0076] Another possible option: the first wiring terminal 21 is connected to the negative pole of the power supply, and the second wiring terminal 22 is connected to the positive pole of the power supply. Figure 3 is a schematic diagram of the arc movement of the electromagnetic contactor embodiment of the application with a permanent magnet bidirectional arc extinguishing device when the power supply is reversely connected, which extends through the middle plane of the first moving contact 31, the second moving contact 32 and the first stationary contact 11 and the second stationary contact 12 of Figure 1 .

[0077] As shown in Figure 3As shown, when the main circuit of the contactor is disconnected, an arc is generated between the first moving contact 31 and the first static contact 11, that is, the first main contact 91 generates an arc, which is driven by the magnetic field force to move downward into the first channel 111, and the moving direction of the arc is shown by arrow C; an arc is generated between the second moving contact 32 and the second static contact 12, that is, the second main contact 92 generates an arc, which is driven by the magnetic field force to move upward into the fourth channel 114, and the moving direction of the arc is shown by arrow D.

[0078] The movement of the arc under the influence of the magnetic field can be divided into the following two stages:

[0079] Phase 1: The arc generated by the first main contact 91 and the arc generated by the second main contact 92 begin to move due to the magnetic field force. At this point, current flows from the second terminal 22 through the second static contact 12, the second movable contact 32, the movable contact assembly 3, the first movable contact 31, and the first static contact 11 to the first terminal 21. This phase continues until the arcs reach the ends of the third arc-starting runner 141 and the tenth arc-starting runner 144, respectively.

[0080] Stage 2: When the arc generated by the first main contact 91 reaches the end of the third arc runner 141, it discharges a spark onto the fifth arc runner 161 of the large arc runner 15. When the arc generated by the second main contact 92 reaches the end of the tenth arc runner 144, it discharges a spark onto the twelfth arc runner 164 of the large arc runner 15. At this point, current flows from the second terminal 22 through the second static contact 12, the eighth arc runner 134, the twelfth arc runner 164, the large arc runner 15, the fifth arc runner 161, the first arc runner 131, and the first static contact 11, to the first terminal 21.

[0081] The arc generated by the first main contact 91 is stretched by the arc-striking runner, passes through the first channel 111, and is finally extinguished in its associated arc-extinguishing hood. The arc generated by the second main contact 92 is stretched by the arc-striking runner, passes through the fourth channel 114, and is finally extinguished in its associated arc-extinguishing hood.

[0082] The second situation: the connection terminals of the electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device are connected to an AC power supply.

[0083] When the arc is formed in the half-sine wave stage, it is in the state of Figure 2 At a power frequency of 50 Hz, the positive half-wave lasts for about 10 ms, which is enough time for the arc to spark from the fourth arc-starting guide plate 142 and the ninth arc-starting guide plate 143 associated with the moving contact assembly 3 to the corresponding sixth arc-starting guide plate 162 and the eleventh arc-starting guide plate 163 on the large arc-starting plate 15. The arc movement process is the same as when the first terminal 21 is connected to the positive pole of the power supply and the second terminal 22 is connected to the negative pole of the power supply.

[0084] When the arc is formed in the negative half-wave stage, the state is as shown in Figure 3 At this time, the arc spark discharges from the third arc guide plate 141 and the tenth arc guide plate 144 associated with the moving contact assembly 3 to the corresponding fifth arc guide plate 161 and the twelfth arc guide plate 164 on the large arc plate 15, and the arc moving process is the same as when the first wiring terminal 21 is connected to the negative pole of the power supply and the second wiring terminal 22 is connected to the positive pole of the power supply.

[0085] The electromagnetic contactor with the permanent magnet bidirectional arc extinguishing device provided by the application is a single-pole contactor. It should be understood that the electromagnetic contactor can be a single-pole contactor or a multi-pole contactor, and the application does not limit this.

[0086] The application discards the shortcomings of various arc extinguishing devices in the existing contactors, integrates the advantages of various arc extinguishing devices in the existing contactors, realizes the breaking of bidirectional direct current and power frequency alternating current, ensures low cost, convenient maintenance and simple manufacturing, and meets the demand for compact design of the product.

Claims

1. An electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device, comprising a contactor unit, an arc extinguishing unit and a bracket body; the contactor unit comprises a contactor, a first terminal (21), a second terminal (22) and a magnetic circuit assembly (4); the contactor comprises a first static contact (11) electrically connected to the first terminal (21), a second static contact (12) electrically connected to the second terminal (22), and a moving contact assembly (3); the moving contact assembly (3) comprises a first moving contact (31) and a second moving contact (32) fixed together and electrically connected; the first static contact (11) and the first moving contact (31) constitute a first main contact (91); the second static contact (12) and the second moving contact (32) constitute a second main contact (92); the bracket body is used for connecting and fixing the various parts of the contactor unit and the arc extinguishing unit; Its characteristics are: The arc extinguishing unit includes an arc extinguishing hood, two parallel and oppositely arranged magnetic conductive pole plates, one or more sets of permanent magnet components, two sets of positive arc extinguishing components, and two sets of negative arc extinguishing components; the one or more sets of permanent magnet components are fixed between the two magnetic conductive pole plates; the two sets of positive arc extinguishing components and the two sets of negative arc extinguishing components are both located in the arc extinguishing hood; the one or more sets of permanent magnet components form an arc extinguishing magnetic field between the two magnetic conductive pole plates; the permanent magnets of the multiple sets of permanent magnet components have the same polarity; The permanent magnet assembly includes a permanent magnet, and two magnetic cores coaxially connected to the permanent magnet and located at both ends of the permanent magnet; the outer ends of the two magnetic cores are respectively connected to a magnetic conductive pole plate; A first group of positive arc extinguishing components is arranged on one side of the first static contact (11) and the first moving contact (31), and a first group of negative arc extinguishing components is arranged on the other side of the first static contact (11) and the first moving contact (31); a second group of positive arc extinguishing components is arranged on a side of the second static contact (12) and the second moving contact (32) away from the first group of positive arc extinguishing components, and a second group of negative arc extinguishing components is arranged on the other side of the second static contact (12) and the second moving contact (32); Each group of positive arc extinguishing components includes a positive lower arc guide plate, a positive middle arc guide plate and a positive upper arc guide plate; wherein: the first group of positive arc extinguishing components respectively includes a second arc guide plate (132), a fourth arc guide plate (142) and a sixth arc guide plate (162); the second arc guide plate (132) is located below the first static contact (11) and is connected to the first static contact (11), and its end is tilted and bent downward; the fourth arc guide plate (142) is located above the first moving contact (31) and is connected to the first moving contact (31), and its end is tilted and bent upward; the sixth arc guide plate (162) is located below the first static contact (11) and is connected to the first static contact (11), and its end is tilted and bent upward; The fourth arc-striking guide plate (142) is placed horizontally above the second moving contact (32); the second group of positive arc-extinguishing components respectively includes a seventh arc-striking guide plate (133), a ninth arc-striking guide plate (143) and an eleventh arc-striking guide plate (163); the seventh arc-striking guide plate (133) is located below the second static contact (12) and is connected to the second static contact (12), and its end is tilted and bent downward; the ninth arc-striking guide plate (143) is located above the second moving contact (32) and is connected to the second moving contact (32), and its end is tilted and bent upward; the eleventh arc-striking guide plate (163) is located above the ninth arc-striking guide plate (143) and is placed horizontally; Each set of reverse arc extinguishing components includes a reverse lower arc-striking guide plate, a reverse middle arc-striking guide plate and a reverse upper arc-striking guide plate; wherein: The first group of reverse arc extinguishing components respectively includes a first arc-striking guide plate (131), a third arc-striking guide plate (141) and a fifth arc-striking guide plate (161); the first arc-striking guide plate (131) is located below the first static contact (11) and is connected to the first static contact (11), and its end portion is tilted and bent downward; the third arc-striking guide plate (141) is located above the first moving contact (31) and is connected to the first moving contact (31), and its end portion is tilted and bent upward; the fifth arc-striking guide plate (161) is located above the third arc-striking guide plate (141) and is placed horizontally; The second group of reverse arc extinguishing components respectively includes an eighth arc-striking guide plate (134), a tenth arc-striking guide plate (144) and a twelfth arc-striking guide plate (164); the eighth arc-striking guide plate (134) is located below the second static contact (12) and is connected to the second static contact (12), and its end is tilted and bent downward; the tenth arc-striking guide plate (144) is located above the second moving contact (32) and is connected to the second moving contact (32), and its end is tilted and bent upward; the twelfth arc-striking guide plate (164) is located above the tenth arc-striking guide plate (144) and is placed horizontally.

2. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 1, characterized in that: Also included are two pairs of small plates; There are two groups of permanent magnet components, one of which includes a first permanent magnet (51), a first magnetic core (61), and a second magnetic core (62), and the other includes a second permanent magnet (52), a first magnetic core (61), and a second magnetic core (62). The two pairs of small polar plates include a pair of first small polar plates (71) and a pair of second small polar plates (72); The magnetic conductive pole plate comprises a first large pole plate (81) and a second large pole plate (82); The two first magnetic cores (61) are respectively connected together via a first small pole plate (71) and a first large pole plate (81); and the two second magnetic cores (62) are respectively connected together via a second small pole plate (72) and a second large pole plate (82).

3. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 2, characterized in that: The fifth arc-striking guide plate (161), the sixth arc-striking guide plate (162), the eleventh arc-striking guide plate (163), and the twelfth arc-striking guide plate (164) are interconnected to form a large arc-striking plate (15).

4. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 3, characterized in that: There are intervals between the third arc-striking guide plate (141), the fourth arc-striking guide plate (142), the ninth arc-striking guide plate (143), the tenth arc-striking guide plate (144) and the large arc-striking plate (15).

5. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 4, characterized in that: The widths of the third arc-striking guide plate (141), the fourth arc-striking guide plate (142), the ninth arc-striking guide plate (143), and the tenth arc-striking guide plate (144) are smaller than the widths of the first arc-striking guide plate (131), the second arc-striking guide plate (132), the seventh arc-striking guide plate (133), the eighth arc-striking guide plate (134), and the large arc-striking plate (15).

6. The electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 5, characterized in that: The permanent magnet and the magnetic core are both cylindrical.

7. An arc extinguishing method for an electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to any one of claims 1 to 6, characterized in that: Step 1: Connect the first wiring terminal (21) and the second wiring terminal (22) to two ends of a power source respectively; Step 2: When the magnetic circuit assembly (4) is actuated to disconnect the main circuit of the contactor, an arc is generated between the first moving contact (31) and the first static contact (11), and an arc is generated between the second moving contact (32) and the second static contact (12); Step three: through the magnetic field force between the two magnetic conductive plates, the arc moves along the corresponding arc-starting guide plate and finally moves into the arc extinguishing cover to complete the arc extinguishing.

8. The arc extinguishing method for an electromagnetic contactor with a permanent magnet bidirectional arc extinguishing device according to claim 7, characterized in that: In step 1, the power supply is a DC power supply or an AC power supply.

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