RU2153727C1 - Electromagnetic contactor and its control process - Google Patents

Abstract

FIELD: magnetic-air-blast circuit-opening devices. SUBSTANCE: contactor has insulating plate that mounts two cheeks with electromagnetic operating mechanism, insulators, movable and fixed contacts, terminal leads, blowout coil, magnetic system, arcing horns, and chamber placed between them. Arc suppression is effected due to its ejection by magnetic field into arc-control chamber with blowout coil connected to supply voltage only for the time of arc suppression. This is attained due to appropriate mechanical design of movable and fixed contacts, arcing horns, and blowout coil circuit arrangement. Contactor control process includes short-time connection of blowout coil to power supply in the course of closing and opening of contact members. EFFECT: reduced power loss, simplified design, improved operating reliability. 2 cl, 1 dwg

Description

 The invention relates to the field of electrical engineering and can be used in electrical apparatuses with magnetic arc extinction in air.

 Known electromagnetic contactor containing an insulating plate, an insulator, an arcing coil with a core and two poles, a fixed and movable contact, two terminals, two arcing horns, an electromagnetic drive, an arcing chamber [1].

 In the known design of the contactor, the electromagnetic drive is mounted on the insulating plate cantilever, the arcing coil is connected in series to the main power circuit between the first terminal and the fixed contact, and structurally it is located together with the fixed contact and the first arcing horn on the insulator, the fixed contact and the first arcing horn are electrically connected . The second arcing horn is located directly on the movable contact, electrically connected to the second terminal and mechanically connected to the armature of the electromagnetic drive. When the arc arising when the contacts are opened, the latter is blown forward and upward into the arcing chamber.

 Another electromagnetic contactor is known, comprising an insulating plate, an insulator, an arcing coil with a core and two poles, a fixed and movable contact, two terminals, two arcing horns, an electromagnetic drive, an arcing chamber [2].

 In the known design of the contactor, the electromagnetic drive is mounted on the insulation plate cantilever by means of a special bracket, the arcing coil is connected in series to the main power circuit between the first terminal and the fixed contact, and structurally it is located on the insulator together with the fixed contact and the first arcing horn, the fixed contact and the first arcing the horn is electrically connected. The movable contact is electrically connected to the second output and mechanically connected to the armature of the electromagnetic drive, the second arcing horn through the insulating plate is fixed to the bracket.

 The disadvantages of the described electromagnetic contactors include the following. The cantilever fixing of the nodes on the insulating plate causes the introduction of additional reinforcing mechanical parts into the design and limits the possibility of designing in front placement of arcing devices (blowing the arc only forward), as required by the conditions for placing electromagnetic contactors in vehicles, for example, in car boxes. When using electromagnetic contactors for switching high-voltage circuits in railway transport, where the significant dimensions of the arcing chamber and its front position with respect to the contactor are determined by the features of arc tearing and extinction, operating conditions, cantilever fixing of nodes on the insulating plate is generally difficult.

 The implementation of the method of controlling the electromagnetic contactor by closing and opening the movable and fixed contacts with the subsequent removal of the arc arising when the contacts diverge into the arcing horns and then into the arcing chamber when the arcing coil is connected in series to the load circuit leads to unjustified power losses when the contactor is in the closed state, and also to the need to charge the core and magnetic poles of the arcing coil in order to exclude significantly x eddy current losses when using contactors in AC circuits.

 The invention solves the problem of reducing power losses during the operation of the contactor, simplifying its design and improving consumer properties.

 To solve the problems posed by the device, an electromagnetic contactor containing an insulating plate with a first insulator and an electromagnetic drive fixed to it, a fixed contact located on the first insulator, a movable contact mechanically connected to the electromagnetic drive, connected to the second terminal of the electromagnetic contactor, located next to the first of the insulator is an arcing coil with a core equipped with two poles covering the contact interaction zone, an arcing chamber ru, inserted between the poles and covering the contact interaction zone, installed inside the arcing chamber, the first arcing horn mounted on the said insulator, the second arcing horn, the first output of the contactor connected to the first output of the arcing coil, two cheeks mounted on the insulating plate are inserted, between which are installed the first, second and third insulators, the second arcing horn is mounted on the second insulator, the second output of the contactor is installed on the third insulator, the first and the second arcing horns are located on the ends of the respectively fixed and movable contacts facing the interior of the arcing chamber, the first arcing horn is electrically connected to the second terminal of the arcing coil, and the first terminal of the contactor is connected to the fixed contact, the movable contact is bent at the end towards the first arcing horn .

 To solve the set tasks, in the part of the method in which the movable and stationary contacts are closed and their contacts are opened, followed by the removal of the arc arising when the contacts diverge into the arcing horns by means of the buoyancy force created by the magnetic field of the arcing coil, and by extinguishing the stretched arc in the arcing chamber, by closing the mentioned contacts, touching the bend of the movable contact and the first arcing horn, and after closing - slipping the bend movably contact of the first arcing horn, opening of the bend of the movable contact and the first arcing horn is performed after the opening of the movable and stationary contacts.

 The invention is illustrated in the drawing.

 The electromagnetic contactor contains an insulating plate 1, cheeks 2 (one of them is shown in side view), an electromagnetic drive 3, a movable contact 4 with a bend 5, a fixed contact 6, a first insulator 7, a first arcing horn 8, a second arcing horn 9, and a second insulator 10, the third insulator 11, the first terminal 12, the second terminal 13, the conductor 14, the arcing coil 15 with the core 16, the poles 17 (one of them is shown in dashed lines), the arcing chamber 18.

 The cheeks 2 are installed on the insulating plate 1, the electromagnetic drive 3 is fixed between the cheeks 2 with screws and studs, the arc extinguishing coil 15 with the core 16, the insulators 7, 10, 11 with the fixed contact 6 fixed to them, the first and second arcing horns 8, 9 and conclusions 12 and 13. The poles 17 cover the cheeks 2 from the outside, the arcing chamber 18 is inserted between the poles 17 into the space between the cheeks 2, covering the contact area of contacts 4 and 6. The movable contact 4 is electrically connected to the second terminal by means of a conductor 14 13, the fixed contact 6 is electrically connected to the first terminal 12 and the first terminal of the arcing coil 15, the second terminal of which is electrically connected to the first arcing horn 8. The movable contact 4 is mechanically connected to the movable part of the electromagnetic drive 3 through a system of levers.

 The electromagnetic contactor operates as follows.

 In the closing mode, the electromagnetic actuator 3 is activated, and the movement of the movable contact 4 to the fixed contact 6 starts. The first touches the first arcing horn 8, the bend 5 of the movable contact 4, then the movable contact 4 and the fixed contact 6 are closed, while the bend 5 slides along the first arcing horn 8. In the closed state of the movable and stationary contacts 4 and 6, respectively, the arcing coil 15 is shunted by them and de-energized.

 In the opening mode, when removing the force developed by the electromagnetic actuator 3, the process of contact divergence begins. The fixed contact 4 and the movable contact 6 are the first to open, while the bend 5 slides along the first arcing horn 8, providing mechanical and electrical contact with it. At this moment, a power current flows through the arcing coil 15 along the circuit: the first terminal 12 - turns of the arcing coil 15 - the first arcing horn 8 - bend 5 - movable contact 4 - conductor 14 - second terminal 13. The current flowing through this circuit leads to a magnetic flow in the core 16 and between the poles 17 in the interaction zone of the movable and fixed contacts 4, 6, respectively. With the further movement of the movable contact 4 downward, the bend 5 departs from the first arcing horn 8, an electric arc arises between the movable and fixed contacts. Serial connection of the arcing coil to the power circuit when the contacts are opened allows you to always orient the magnetic field between the poles so that the arising arc is stretched from contacts 4 and 6 to the arcing horns 8, 9, blown into the arcing chamber 18 and went out there [2]. When the state of the contacts is open and the arc is extinguished, the current does not flow through the arcing coil either.

Sources of information
1. N. M. Batalov, B. P. Petrov "Traction electric devices" M., "Energy", 1969 - 240 p.

 2. A.A. Chunikhin "Electrical apparatus" M. "Energoatomizdat", 1988 - 720 p.

Claims (2)

 1. An electromagnetic contactor comprising an insulating plate with a first insulator and an electromagnetic drive fixed thereon, a fixed contact located on the first insulator, a movable contact mechanically connected to the electromagnetic drive, connected to the second terminal of the electromagnetic contactor, an arc extinguishing coil with a core adjacent to the first insulator equipped with two poles covering the contact interaction zone, an arcing chamber inserted between the poles and covering at the contact interaction, the first arcing horn mounted on the said insulator has a second arcing horn installed inside the arcing chamber, the first horn of the contactor being connected to the first output of the arcing coil, characterized in that two cheeks are fixed on the insulating plate, between which the first, second and the third insulators, the second arcing horn is mounted on the second insulator, the second output of the contactor is installed on the third insulator, the first and second arcing horn are located s side ends respectively fixed and movable contacts, the inwardly facing arc extinguishing chamber, a first arcing horn electrically connected to the second terminal of the coil arc, and a first terminal of the contactor is coupled with the fixed contact, the movable contact is formed with a bend on the end towards the first arcing horn.  2. A method for controlling an electromagnetic contactor, in which the movable and fixed contacts are closed and their contacts are opened, followed by removal of the arc arising when the contacts diverge into the arcing horns by means of the buoyant force generated by the magnetic field of the arcing coil, and by extinguishing the extended arc in the arcing chamber, characterized in that before closing the mentioned contacts, they ensure that the bend of the movable contact and the first arcing horn are touched, and after the closure, they slip Binding of bend of the movable contact of the first arcing horn, opening of the bend of the movable contact and the first arcing horn is performed after the opening of the movable and stationary contacts.