RU158287U1 - ELECTROMAGNETIC CONTACTOR - Google Patents

Abstract

An electromagnetic contactor comprising a supporting bracket, an electromagnet, a traverse with movable main and auxiliary contacts of a bridge type, a lead, contact pads with fixed main contacts, fixed auxiliary contacts, an arcing chamber, diodes and mounting conductors, characterized in that the fixed main contacts are made in the form flat tires, and each contact is equipped with a limb, on which a U-shaped shoe is fixed, and the ends of the contacts are brought out to the side faces of the contact blocks, on On the outer edges of the ends of the movable main contacts, protrusions for the exit of the electric arc are made, the cores of the electromagnet are made at least 1.65 times shorter than the distance between them, a mounting block for the placement and electrical connection of the diodes installed in the inner part of the carrier bracket is introduced.

Description

The utility model relates to the field of electrical engineering, in particular to low-voltage equipment for alternating current, and can be used to turn on and off electric power receivers, including squirrel-cage induction motors.

Known electromagnetic contactor KM2000 [1], containing an electromagnetic drive, a contact-extinguishing system, a system of auxiliary contacts, a system of levers mounted on a metal plate. To increase resistance to mechanical stresses, the moving system of the contactor by means of levers and additional load is statically balanced.

The main disadvantages of this contactor are low mechanical wear resistance, large dimensions and weight.

Known also is the electromagnetic contactor KNT400 [2] for a rated current of 200 A, which is the closest analogue of the proposed utility model, selected as a prototype. The design of the contactor contains a supporting bracket, an electromagnetic drive, a crosshead with movable main and auxiliary contacts of the bridge type, a lead, fixed main and auxiliary contacts, two contact insulating blocks, an arcing chamber, diodes used to power the electromagnet coils, conductors of external electrical wiring. The bearing bracket, the anchor, the last two elements - the traverse and the leash are connected pivotally.

The disadvantages of the prototype are large dimensions and weight, due to the following structural reasons:

- the fixed contacts of the main contacts have a design in the form of rectangular rectangular racks, which are brought out through the slots in the arcing chamber to the front surface of the contactor and equipped with bolt clamps for external connections. The implementation of such a design of the terminals increases the overall dimensions in height by more than 10%, as well as the mass of the contactor;

- the diodes are mounted on insulating blocks mounted on a support bracket on the sides of the contactor, the blocks with diodes protruding beyond the contact insulating blocks and increase the overall dimensions of the contactor;

- fixed auxiliary contacts, the conclusions of the including coils and diodes are connected by conductors by an external hinged electrical installation, protruding beyond the contact insulating blocks, which increases the overall dimensions of the contactor in width and height and its mass;

- the electromagnet cores are made with a length exceeding 2.2 times the distance between them, which leads to an increase in the scattering fluxes, power consumption and, in general, an increase in contactor mass.

The aim of the proposed technical solution is to reduce the overall dimensions and mass of the electromagnetic contactor.

The technical result of the proposed technical solution is achieved by the fact that in an electromagnetic contactor containing a supporting bracket, an electromagnet, a traverse with movable main and auxiliary contacts of a bridge type, a lead, contact pads with fixed main contacts, fixed auxiliary contacts, an arcing chamber, diodes and mounting conductors, the fixed main contacts are made in the form of flat tires, each contact having a limb on which a U-shaped shoe is fixed, and the ends ontacts are brought out to the side faces of the contact blocks, on the upper faces of the ends of the movable main contacts, protrusions are made for the electric arc to exit, the cores of the electromagnet are made at least 1.65 times shorter than the distance between them, which is determined on the basis of optimization calculations, a mounting block is introduced for placement and electrical connection of diodes mounted in the inner part of the carrier bracket.

The essence of the technical solution of the utility model lies in the fact that the implementation of the fixed main contacts in the form of flat tires, each contact is equipped with a bend, on which a shoe made of a U-shape is fixed, the ends of the contacts are brought out to the side faces of the contact blocks, the protrusions are made for the electric arcs on the upper faces of the ends of the bridges of the main contacts, the implementation of an electromagnet with a core length of at least 1.65 times less than the distance between them, as well as the introduction of a mounting block for displacements and electrical connection of diodes and placing it into the inner part of the bearing bracket it possible to achieve downsizing and weight contactor.

The design of the proposed technical solution is illustrated by drawings, which depict:

in FIG. 1 - electromagnetic contactor, front view, section;

in FIG. 2 - electromagnetic contactor, front view;

in FIG. 3 - electromagnetic contactor, bottom view, section AA;

in FIG. 4 - traverse with movable bridge contacts;

in FIG. 5 - fixed main contact;

in FIG. 6 - block with fixed auxiliary contacts.

The electromagnetic contactor contains a support bracket 1, an electromagnet consisting of a yoke 2, two cores 3, two retracting coils 4, a rotary armature 5, a crosshead 6 with movable main 7 and auxiliary 8 contacts of the bridge type, lead 9, two symmetrical contact blocks 10 with installed on them the fixed main contacts 11, the arcing chamber 12. The bearing bracket 1, the anchor 5, the yoke 6 and the leash 9 are pivotally connected. The bearing bracket 1 is made of a U-shaped. The fixed main contacts 11 are made in the form of flat tires and are provided with bends 13 perpendicular to the base of the contact, U-shaped shoes 14 with soldered contact parts are fixed on the bends (Fig. 5). The ends of the fixed main contacts 11 are displayed on the side faces of the contact blocks 10 (Fig. 2). On the upper faces of the ends of the movable main contacts 7 are made protrusions 15 for the exit of the electric arc (Fig. 4). The cores 3 of the electromagnet are made with a length (H) not exceeding 1.65 times the distance (C) between them (Fig. 3). Diodes and mounting conductors are placed inside the bends of the supporting bracket 1 in the mounting block 16 (Fig. 1 and 2). Fixed auxiliary contacts 17 are mounted on insulating blocks 18 (Fig. 6).

The electromagnetic contactor operates as follows. In the initial position, in the absence of voltage in the control circuit, the closing contacts are in the open state. When voltage is applied to the switching coils 4, the anchor 5 is attracted to the cores 3, which leads to the movement of the traverse 6 with movable contacts 7 and 8 and their closure with fixed contacts 11 and 17. If there is voltage at the input terminals of the main contacts and the load is connected to the output contacts , for example, an electric motor, it turns on. When the voltage is turned off from the switching coil, the anchor 5 moves away from the cores 3, the contacts open and the load is disconnected from the network.

Making a fixed contact in the form of a flat tire 11 with a bend 13 at an angle of 90 ° with a U-shaped shoe 14 with a contact part, a tight arrangement of the contact system is achieved and, consequently, overall dimensions are reduced.

The protrusions 15, made on the side faces of the movable contacts 7, and the U-shaped shoe 14 during the opening of the electric circuit provide arc movement to the front of the contactor, and the conclusions for connecting the external wires are placed on the sides. This allows you to achieve the required insulation distance with reduced overall dimensions of the contact-arcing device, which also reduces the overall dimensions of the electromagnetic contactor.

As a result of studies on the optimization of U-shaped magnetic systems with two cores, it was found that the ratio of the core length H to the distance between them C significantly affects the magnitude of the traction force, while the minimum mass of active materials (steel and copper) is achieved by constructing an electromagnet with the ratio H / C≤1.65.

The manufacture of prototypes of contactors for a rated current of 250 A according to the technical solution described and performance tests showed that the decrease in mass (specific weight, kg / A) and dimensions (specific value of the overall volume, dm ³ / A) compared with the prototype (contactor KNT-400 for a rated current of 200 A) amounted to 12% and 43%, respectively.

Information sources:

1. Contactors electromagnetic KM2000 series. [Electronic resource] - URL: http://reostat.ru/production/cat-1/km2000/km2000-pcuk (12.22.2014).

2. Catalog "Contactors electromagnetic three-pole alternating current of the KNT series" [Electronic resource] - URL: http://www.uralelectro.ru/upload/file/KNT.doc (12.22.2014).

Claims (1)

An electromagnetic contactor comprising a supporting bracket, an electromagnet, a traverse with movable main and auxiliary contacts of a bridge type, a lead, contact pads with fixed main contacts, fixed auxiliary contacts, an arcing chamber, diodes and mounting conductors, characterized in that the fixed main contacts are made in the form flat tires, and each contact is equipped with a limb, on which a U-shaped shoe is fixed, and the ends of the contacts are brought out to the side faces of the contact blocks, on On the outer edges of the ends of the movable main contacts, protrusions for the exit of the electric arc are made, the cores of the electromagnet are made at least 1.65 times shorter than the distance between them, a mounting block for the placement and electrical connection of the diodes installed in the inner part of the carrier bracket is introduced.

Images