CN204390940U - DC contactor arc-extinguisher - Google Patents

Abstract

The utility model provides an arc extinguishing device for a DC contactor, which comprises a connecting plate, an extinguishing shield, a leaf spring, a contact bridge, a contact, a permanent magnet, a heat insulation sleeve, an arc starting piece, an arc extinguishing grid, a contactor head. Permanent magnets, plastic heat insulation sleeves, arc starting parts, and arc extinguishing grids are arranged in the shield; the permanent magnet is located in the middle of the arc starting parts, and there is a gap between the permanent magnets and the arc starting parts, and the arc starting parts are easy to magnetize It is made of soft magnetic material; the permanent magnet is wrapped by the plastic heat insulation sleeve, and the plastic heat insulation sleeve is connected with the arc starting piece; the plastic heat insulation sleeve is made of gas-generating material. The beneficial effect of the utility model is: it solves the defect of high-temperature demagnetization existing in permanent magnet arc extinguishing, the design is reasonable and novel compared with similar products, and finally realizes the arc extinguishing by using two methods of magnetic blowing arc extinguishing and grid sheet arc extinguishing .

Description

DC contactor arc extinguishing device

technical field

The utility model relates to an arc extinguishing chamber, in particular to an arc extinguishing device for a DC contactor.

Background technique

The utility model belongs to the arc-extinguishing technology of a large-current DC arc-extinguishing chamber, and adopts an insulating and heat-insulating device to separate a permanent magnet from an external heat-conducting part.

A DC contactor is an electrical appliance suitable for frequently connecting and disconnecting DC main circuits and large-capacity control circuits over a long distance. DC contactors are widely used in DC systems, such as urban rail, subway, charging pile, communication industry, photovoltaic system and many other fields. In order to quickly extinguish the arc, DC contactors generally use a magnetic blowing arc extinguishing device. For small-capacity DC contactors, permanent magnets are also used to generate magnetic blowing force. For medium and large-capacity contactors, longitudinal slot arc extinguishing and magnetic blowing are often used. Arc extinguishing method. Now the permanent magnet arc extinguishing technology is generally used, but in the high temperature environment generated by the arc, the unprotected permanent magnet will gradually demagnetize as the temperature rises.

Utility model content

In order to improve the breaking capacity of the small circuit breaker, the utility model has invented a DC contactor arc extinguishing device to replace the original old-fashioned arc extinguishing chamber. It has the characteristics of simple structure and high arc extinguishing efficiency, which can greatly increase the breaking capacity of the circuit breaker and ensure the reliable operation of the power grid.

The technical solution adopted by the present invention to solve its technical problems is:

An arc extinguishing device for a DC contactor, comprising a connecting plate, an extinguishing shield, a leaf spring, a contact bridge, a contact, a permanent magnet, a heat insulating sleeve, an arc starting piece, an arc extinguishing grid, and a contact. The permanent magnet, plastic heat insulation sleeve, arc striker and arc extinguishing grid are arranged in the shield; the permanent magnet is located in the middle of the arc striker, and there is a gap between the permanent magnet and the arc striker; the plastic shell heat insulation sleeve The permanent magnet is wrapped, and the plastic heat insulation sleeve is connected with the arc starting piece; the plastic heat insulation sleeve is made of gas-generating material.

The beneficial effects of the invention are: the defect of high temperature demagnetization in permanent magnet arc extinguishing is solved, the design is reasonable and novel compared with similar products, and the arc extinguishing is finally realized by using two methods of magnetic blowing arc extinguishing and grid sheet arc extinguishing.

Description of drawings

Below according to embodiment and accompanying drawing, the utility model is described in further detail.

Fig. 1 is a schematic diagram of the overall structure of the utility model, partly cut away inside and out.

Figure 2 is the front view of the arc starter

Figure 3 is the front view of the assembly components of the arc starter, heat insulation sleeve and permanent magnet

Figure 4 is a top view of the assembly components of the arc starter, heat insulation sleeve and permanent magnet

Figure 5 is a cross-sectional view of the direction shown in Figure 4

Reference signs:

1. Connection plate, 2. Extinguisher shield, 3. Leaf spring, 4. Contact bridge, 5. Contact, 6. Permanent magnet, 7. Heat insulation sleeve, 8. Arc starter, 9. Arc extinguishing grid Sheet, 10. Contact

Detailed ways

Please refer to Fig. 1-5 as shown: a DC contactor arc extinguishing device described in the utility model, including a connecting plate 1, an extinguishing shield 2, a leaf spring 3, a contact bridge 4, a contact 5, and a permanent magnet 6 , Heat insulation sleeve 7, arc striker 8, arc extinguishing grid 9, contact 10. The permanent magnet 6, the plastic heat insulation sleeve 7, the arc starting part 8 and the arc extinguishing grid 9 are arranged in the extinguishing shield 2; the permanent magnet 6 is located in the middle of the arc starting part 8, between the permanent magnet 6 and the arc starting part 8 There is a gap, and the arc extinguishing part is made of soft magnetic material that is easy to magnetize; the plastic heat insulating sleeve 7 wraps the permanent magnet 6, and the plastic heat insulating sleeve 7 is connected with the arc starting part 8; the plastic heat insulating sleeve 7 is Made of gas producing material.

The working process is as follows:

As shown in Figure 2, it is the front view of the arc starting part 8, and the arc starting part 8 is assembled with the permanent magnet 6 and the heat insulation sleeve 7, wherein the heat insulation sleeve 7 serves the purpose of fixing the permanent magnet 6 and heat insulation, The assembled model is shown in Figure 3. The permanent magnet 6 magnetizes the arc starting part 8 and forms a closed magnetic field on both sides of the arc starting part 8. As shown in Figure 3, if the polarity of the permanent magnet 6 is left N right S, The direction of the arrow shown in Figure 3 is the direction of the magnetic field. As shown in Figure 1, the contact 10 is installed directly below the permanent magnet 6. When the moving and static contacts are separated, the position where the arc is generated is in the area of the magnetic field envelope, and the arc is generated At this time, under the action of the magnetic field force, the arc quickly enters the arc extinguishing grid 9. Since the magnetic resistance of the metal grid is much smaller than that of air, the magnetic flux on the upper part of the arc easily passes through the metal grid to form a closed magnetic circuit. Just cause the magnetic field in the air around the arc to be sparse at the top and dense at the bottom. This magnetic field exerts an upward force on the arc, pulling the arc into the gap between the grids, and the grid divides the arc into several short arcs connected in series. Each grid piece becomes the electrode of the short arc, and the total arc voltage drop is divided into several sections, so that the arc voltage between each grid piece exceeds the supply voltage, and at the same time, the grid piece absorbs and dissipates the heat of the arc, so that the arc is cooled rapidly, and the arc is promoted as soon as possible. off.

The above-mentioned embodiment is only to describe the preferred implementation of the utility model, not to limit the scope of the utility model. Any modifications, equivalent replacements, improvements, etc., should fall within the scope of protection determined by the claims of the present utility model.

Claims (1)

1. A DC contactor arc extinguishing device, comprising a connecting plate (1), an extinguishing shield (2), a leaf spring (3), a contact bridge (4), a contact point (5), a permanent magnet (6), The heat insulation sleeve (7), the arc striker (8), the arc extinguishing grid (9), and the contact (10), are characterized in that: the permanent magnet (6), the plastic heat insulation sleeve (7), the arc striker (8), the arc extinguishing grid (9) is arranged on the extinguishing shield (2); wherein the permanent magnet (6) is located in the middle of the arc starting part (8), between the permanent magnet (6) and the arc starting part (8) There is a gap, and the arc starting part (8) is made of soft magnetic material that is easy to magnetize; the plastic shell heat insulating sleeve (7) wraps the permanent magnet (6), and the plastic heat insulating sleeve (7) and the arc starting part (8) connected; the plastic insulation sleeve (7) is made of gas-generating material.