阅读说明：本技术 双断点直动式接触器中的随动永磁磁场灭弧机构 (Follow-up permanent magnetic field arc extinguishing mechanism in double-breakpoint direct-acting contactor ) 是由 乔瑜菲 由佳欣 周成龙 张永健 蒲永亮 朱月霖 于 2021-09-26 设计创作，主要内容包括：本发明公开了一种双断点直动式接触器中的随动永磁磁场灭弧机构,所述灭弧机构包括动触头、静触头、永磁体、齿条、齿轮、支架、连杆,动触头和齿轮固定于连杆的上部,永磁体包括第一永磁体、第二永磁体、第三永磁体和第四永磁体,第一永磁体和第二永磁体固定在第一支架上,第三永磁体和第四永磁体固定在第二支架上；第一支架和第二支架分别连接两个带有齿条的连杆,采用齿轮齿条传动把永磁体的前后运动与动触头的上下运动关联起来,使两侧永磁体的间距随动触头的运动而改变,从而改变灭弧磁场大小,避免了起弧阶段起弧速度过慢、燃弧阶段器件绝缘耐压性能降低过快,使接触器触头间电弧熄灭速度更快,并保持较高的耐压绝缘性能。(The invention discloses a follow-up permanent magnet magnetic field arc extinguishing mechanism in a double-breakpoint direct-acting contactor, wherein the arc extinguishing mechanism comprises a moving contact, a fixed contact, permanent magnets, a rack, a gear, a bracket and a connecting rod, the moving contact and the gear are fixed on the upper part of the connecting rod, the permanent magnets comprise a first permanent magnet, a second permanent magnet, a third permanent magnet and a fourth permanent magnet, the first permanent magnet and the second permanent magnet are fixed on the first bracket, and the third permanent magnet and the fourth permanent magnet are fixed on the second bracket; the first support and the second support are respectively connected with two connecting rods with racks, the back-and-forth movement of the permanent magnets and the up-and-down movement of the moving contact are related by adopting gear-rack transmission, so that the distance between the permanent magnets on two sides is changed along with the movement of the moving contact, the size of an arc extinguishing magnetic field is changed, the problems that the arc striking speed is too low in an arc striking stage and the insulation and voltage resistance of a device are reduced too fast in an arc burning stage are solved, the arc extinguishing speed between contacts of a contactor is higher, and higher voltage resistance and insulation performance are kept.)

1. The utility model provides a follow-up permanent magnetism magnetic field arc extinguishing mechanism in double-breakpoint direct action type contactor which characterized in that follow-up permanent magnetism magnetic field arc extinguishing mechanism includes moving contact, static contact, permanent magnet, rack, gear, support, connecting rod, wherein:

the moving contact and the gear are fixed on the upper part of the connecting rod, and the gear is positioned below the moving contact;

the permanent magnets comprise a first permanent magnet, a second permanent magnet, a third permanent magnet and a fourth permanent magnet, the first permanent magnet and the second permanent magnet are placed on the left side of the contact gap, and the third permanent magnet and the fourth permanent magnet are placed on the right side of the contact gap;

the first permanent magnet and the second permanent magnet are fixed on the first bracket, and the third permanent magnet and the fourth permanent magnet are fixed on the second bracket;

the first support and the second support are respectively connected with two connecting rods with racks, the racks are positioned on two sides of the gear and meshed with the gear, and the up-and-down motion of the moving contact is converted into the back-and-forth motion of the permanent magnet by utilizing the transmission of the gear and the rack.

2. The follow-up permanent magnetic field arc extinguishing mechanism in the double-breakpoint direct-acting contactor according to claim 1, wherein the connecting rod is cylindrical.

3. The follow-up permanent magnet field arc extinguishing mechanism in the double-breakpoint direct-acting contactor according to claim 1, wherein the first permanent magnet and the third permanent magnet are oppositely disposed, and the second permanent magnet and the fourth permanent magnet are oppositely disposed.

Technical Field

The invention belongs to the technical field of contactors, and relates to a device for arc extinction by using a permanent magnetic field which can move along with the movement of an armature.

Background

When the circuit is opened in the atmosphere, if the opening current and the voltage between the contacts after opening are greater than the arcing current and the arcing voltage, an arc is generated between the contacts. In the case of switching devices, the presence of an electric arc delays the circuit from opening and burning the contacts, which in severe cases may cause the switching device to catch fire and explode. Therefore, how to extinguish the arc as soon as possible is a key point of attention for researchers. Magnetic arc quenching is a typical arc quenching device, in which an arc is driven by electric power to be transversely elongated, so that the arc voltage is increased, the volt-ampere characteristic of the arc is separated from a stable burning point, and the arc is quenched. The magnetic induction intensity B of the arc extinguishing magnetic field is too small, so that the arc starting speed is slow, the magnetic induction intensity B of the arc extinguishing magnetic field is too large, so that the diffusion speed of charged particles is too high, and a large amount of metal particles are attached to the inner wall of an arc extinguishing chamber after arc burning and cooling, so that the voltage-resistant and insulating properties of a device are reduced too fast; therefore, the magnitude of the switching field should be variable during the switching-off process. There is currently no method for varying the magnitude of the magnetic quenching field in the arc quenching device structure.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a follow-up permanent magnetic field arc extinguishing mechanism in a double-breakpoint direct-acting contactor. The structure can ensure that the distance between the two permanent magnets providing the arc extinguishing magnetic field changes along with the process of opening and closing the contact; the permanent magnets are close in distance in the arcing stage, a large arc extinguishing magnetic field is provided, and the over-low arcing speed is avoided; the distance of the permanent magnet is far in the arcing stage, so that the arc extinguishing magnetic field is reduced, and the voltage-resistant and insulating performance of the device is prevented from being reduced too fast.

The purpose of the invention is realized by the following technical scheme:

the utility model provides a follow-up permanent magnetism magnetic field arc extinguishing mechanism in double-breakpoint direct action type contactor, includes moving contact, static contact, permanent magnet, rack, gear, support, connecting rod, wherein:

the moving contact and the gear are fixed on the upper part of the connecting rod, and the gear is positioned below the moving contact;

the permanent magnets comprise a first permanent magnet, a second permanent magnet, a third permanent magnet and a fourth permanent magnet, the first permanent magnet and the second permanent magnet are placed on the left side of the contact gap, the third permanent magnet and the fourth permanent magnet are placed on the right side of the contact gap, the first permanent magnet and the third permanent magnet are oppositely placed, and the second permanent magnet and the fourth permanent magnet are oppositely placed;

the first permanent magnet and the second permanent magnet are fixed on the first bracket, and the third permanent magnet and the fourth permanent magnet are fixed on the second bracket;

the first support and the second support are respectively connected with two connecting rods with racks, the racks are positioned on two sides of the gear and meshed with the gear, and the up-and-down motion of the moving contact is converted into the back-and-forth motion of the permanent magnet by utilizing the transmission of the gear and the rack.

Compared with the prior art, the invention has the following advantages:

the invention provides a contactor with a permanent magnet arc extinguishing device for a double-breakpoint direct-acting type, which relates the back-and-forth movement of a permanent magnet and the up-and-down movement of a moving contact by adopting gear rack transmission, so that the distance between the permanent magnets on two sides is changed along with the movement of a moving contact, the size of an arc extinguishing magnetic field is changed, the problems that the arc striking speed is too slow in an arc striking stage and the insulation and pressure resistance of a device are reduced too fast in an arc burning stage are solved, the arc extinguishing speed between contacts of the contactor is higher, and higher voltage resistance and insulation performance are kept.

Drawings

Fig. 1 is a general structure diagram of a follow-up permanent magnetic field arc extinguishing mechanism in a double-breakpoint direct-acting contactor;

FIG. 2 is a view of the permanent magnet, bracket, rack structure;

FIG. 3 is a structural diagram of the moving contact, the connecting rod and the gear;

in the figure, A-static contact, B-moving contact, C-permanent magnet, C₁-a first permanent magnet, C₂A second permanent magnet, C₃-a third permanent magnet, C₄A fourth permanent magnet, a D-rack, an E-gear, an F-bracket, a G-link.

Detailed Description

The technical solution of the present invention is further described below with reference to the accompanying drawings, but not limited thereto, and any modification or equivalent replacement of the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention shall be covered by the protection scope of the present invention.

The invention provides a design method of a follow-up permanent magnetic field arc extinguishing mechanism applied to a double-breakpoint direct-acting contactor arc extinguishing system, which comprises the following points:

1. the permanent magnets are respectively placed on two sides of a gap between a moving contact and a static contact by utilizing a typical magnetic quenching mode, and the generated magnetic field can drive the electric arc by electric power, so that the electric arc is elongated to two sides and is quenched;

2. the arc extinguishing magnetic field has a closer distance in the arc striking stage, so that the arc striking speed is higher; meanwhile, the arc extinguishing magnetic field is far away in the arc stage, so that the phenomenon that the insulation and voltage resistance of the device is reduced due to the fact that charged particles are excessively and violently diffused is avoided.

3. The part of the contactor which drives the moving contact B to move is an armature, and the movement of the permanent magnet C is related to the movement of the armature.

4. A gear E is sleeved on a connecting rod G below a moving contact B, each side of the permanent magnet C is divided into two parts which are connected through a support F, the permanent magnets C on the two sides are connected with a rack D through the supports F respectively, the up-and-down motion of the moving contact is converted into the back-and-forth motion of the permanent magnet through the gear rack transmission, the distance of the permanent magnet is changed along with the on-off process of a contact, and therefore the purpose that the size of an arc extinguishing magnetic field is variable is achieved.

The specific assembly comprises the following steps:

step S1: and assembling a contact system part, namely assembling a gear E and a moving contact B on a cylindrical connecting rod G. The structure is shown in fig. 3, the moving contact B and the gear E are fixed on the upper part of the cylindrical connecting rod G, and the gear E is positioned below the moving contact B, so that the moving contact B drives the gear E to move through the cylindrical connecting rod G in the breaking motion process.

Step S3: and assembling the permanent magnet C and a bracket F containing the rack D. The structure is shown in fig. 2, each permanent magnet C is divided into two parts which are respectively fixed on two brackets F; the middle of each side bracket F is respectively connected with a connecting rod containing a rack D; therefore, the rack D moves to drive the bracket F and the permanent magnet C on the bracket F to move.

Step S4: and mounting the static contact A on the base.

Step S5: and finally, assembling the gear E and the rack D and assembling the movable contact B and the fixed contact A.

The specific motion process of the permanent magnet is as follows:

1: before the contact is disconnected, the permanent magnets on the two sides are at initial positions and are close to each other;

2: after the contact is disconnected, the armature moves downwards and drives the gear to rotate, and the rack moves along with the rotation of the gear; the left permanent magnet moves leftwards, the right permanent magnet moves rightwards, the distance between the permanent magnets on the two sides is continuously increased, and the arc extinguishing magnetic field is continuously reduced.

In conclusion, the design method of the follow-up permanent magnetic field arc extinguishing mechanism applied to the double-breakpoint direct-acting contactor arc extinguishing system can enable the permanent magnet to move along with the contact breaking process, and change of the arc extinguishing magnetic field from large to small is achieved, so that the problems that the arc striking speed is too slow in the arc striking stage and the insulation and voltage resistance of devices are reduced too fast in the arc burning stage are avoided, the arc extinguishing speed between contacts of a contactor is higher, and meanwhile, higher voltage resistance and insulation performance are kept.