RU211302U1 - Electromagnetic contactor for AC and DC circuits - Google Patents

Abstract

The utility model relates to devices for switching DC and AC circuits. The technical result consists in increasing the reliability of the contactor intended for use in both direct and alternating current circuits. The contactor contains two fixed contacts and two movable contacts placed on a movable jumper, a switching horn, two arc chutes and a permanent magnet configured to blow out a switching arc. In this case, the fixed contact and the corresponding movable contact are connected in potential by a flexible wire, and the switching horn is connected in potential with the same fixed contact, while one arc chute is configured to operate at direct current and in one half-cycle at alternating current, and the other arc chute the camera is configured to operate in another half-cycle with alternating current. 3 w.p. f-ly, 4 ill.

Description

The proposed technical solution relates to devices for switching power circuits, namely to electromagnetic contactors. The proposed contactor is polarized, but it can be used in both direct and alternating current circuits.

Known unidirectionally switching DC contactor with double opening, see RF patent No. 2539360 dated 20.01.2015. This contactor has two contact points, which have one fixed contact and one moving contact, while the moving contacts are located on the contact jumper, and when the contact points are opened, a switching electric arc is formed on each of them. The contactor also contains an electric arc extinguishing device and a displacing device for displacing at least one switching electric arc from the corresponding contact point. The disadvantage of this device is that it can only work with direct current.

The closest device is an electromagnetic contactor, see RF patent No. 2606232 dated 01/10/2017. This contactor contains: two fixed contacts and two movable contacts placed on the movable jumper and forming the first contact place and the second contact place, two arc chutes, the lower of which is located between the fixed contacts, and the upper one is located above the fixed contact and, corresponding to it, the movable contact, a permanent magnet configured to blow out a switching arc formed in the second contact point, and above the movable contact of the second contact point, a switching horn is located near the upper arc chute, while the movable bridge and the switching horn are electrically isolated from each other. The disadvantage of this device is that it cannot work with alternating current.

The task that allows us to solve the proposed contactor is the rapid extinguishing of an electric arc when operating in an alternating current circuit.

The technical result is an increase in the reliability of a contactor operating simultaneously in both direct and alternating current circuits.

The technical result is achieved by the fact that the electromagnetic contactor for DC and AC circuits contains:

two fixed contacts and two movable contacts placed on the movable jumper and forming the first contact point and the second contact point,

two arc chutes, the lower of which is located between the fixed contacts, and the upper one is located above the second contact point - the fixed contact and the corresponding moving contact,

a permanent magnet configured to blow out the commutation arc formed in the second contact area.

Moreover, a switching horn is located above the movable contact of the second contact place near the upper arc chute, while the movable bridge and the switching horn are electrically isolated from each other.

Also, the fixed contact and, corresponding to it, the movable contact of the first contact point are connected by potential with a flexible wire, and the switching horn is connected by potential to the fixed contact of the first contact point, so that the upper arc chute is configured to operate at direct current, and the lower arc chute, made with the ability to work with alternating current in one of the half-cycles.

The switching horn can also be potential-connected to the fixed contact of the first contact point with a flexible wire.

Usually the lower arc chute is smaller than the upper arc chute.

The movable jumper is driven by an electromagnetic drive.

The proposed technical solution is illustrated in Fig. 1-4

Figure 1 shows the device of the proposed electromagnetic contactor.

Figure 2 shows conductive elements and arc chutes.

Figure 3 shows the propagation of the arc during the operation of the contactor at direct current.

Figure 4 shows the propagation of the arc during the operation of the contactor with alternating current.

The figures show:

1, 3 - fixed contact;

2, 4 - arc chute;

5 - permanent magnet;

6 - switching horn (associated with the potential of the fixed contact pos.1);

7 - electromagnetic drive of the movable jumper;

8 - holder of a movable jumper;

9 - movable jumper with two movable contacts;

10, 11 - flexible connection;

12 - contactor frame;

I - the first contact place;

II - contact point.

The main circuit of the proposed electromagnetic contactor consists of two fixed and one movable contact having a bridge type design. The main design feature of this contactor is the flexible connection pos. 11, which bridges one pair of contacts of the first contact place I, formed by contacts pos.1 and pos.9. The advantage of this design is that, when opening, an electric arc occurs only in the second contact point II, formed by contact pos.3 and contact pos.9, above this contact pair there is an arc chute pos.4.

In the DC circuit, the contactor works as follows: the electromagnet pos.7 sets in motion the movable contact pos.9, fixed on the holder pos.8, at the moment of opening the contacts (the electromagnet is disconnected), the arc that has arisen in the second contact place II under the action of the magnetic blowing of the permanent magnet pos.5 moves along the cantatas, see fig.3, comes to the switching horn pos.6 (connected by a flexible connection pos.10 with the contact potential pos.1) and is drawn into the arc chute pos.4, where it stretches over the surface of the arcing plates, cools and goes out (the arc chute has a labyrinth-slot design).

Structurally, contact pos.1 is part of the arc chute pos.4 and serves to stretch the electric arc in the volume of the chamber.

In the alternating current circuit, the contactor works as follows: when the current passes during the positive half-wave period, the arc that has arisen in the first contact place I moves into the arc-extinguishing chamber pos. which has arisen in the second contact point II, moves into the arc chute pos. 2, see Fig. 4. The process of turning off the alternating current is easier, this is due to the transition of the current value in the circuit through zero, therefore the arc chute pos. 2 has significantly smaller volumes.

Figure 2 shows conductive elements and arc chutes. Under one potential there is contact pos.1, contact pos.9 and horn pos.6.

Flexible connection pos. 11 conducts the rated current for a short time only until the electric arc that occurred in the first contact place I passes to the horn pos. for a section designed for the current of the main circuit.

When switching, the contactor does not have critical tripping currents, since a permanent magnet is used in the arc extinguishing system, but the contactor for direct current is polarized. The contactor is designed for switching power circuits and can be used to operate on direct current, bidirectional direct current and alternating current with the ability to quickly extinguish the electric arc, including the critical current range.

Claims (4)

1. An electromagnetic contactor for DC and AC circuits, containing two fixed contacts and two movable contacts placed on a movable jumper and forming the first contact point and the second contact point, two arc chutes, the lower of which is located between the fixed contacts, and the upper one is located above a fixed contact and a corresponding movable contact, a permanent magnet capable of blowing out a switching arc formed in the second contact point, moreover, a switching horn is located above the movable contact of the second contact point near the upper arc chute, while the movable bridge and the switching horn are electrically isolated from each other from another, characterized in that the fixed contact and the corresponding movable contact of the first contact point are connected in potential by a flexible wire, and the switching horn is connected in potential with the fixed contact of the first contact point, such in such a way that the upper arc chute is configured to operate at direct current, and the lower arc chute is configured to operate at alternating current in one of the half-cycles. 2. The electromagnetic contactor according to claim 1, characterized in that the switching horn is connected in potential with the fixed contact of the first contact point by a flexible wire. 3. Electromagnetic contactor according to claim 1, characterized in that the lower arc chute is smaller than the upper arc chute. 4. Electromagnetic contactor according to claim 1, characterized in that the movable jumper is driven by an electromagnetic drive.

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