RU2398366C2 - Electric water heating device of transformer type - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: electric water heater of transformer type is intended for heating of water by quick-acting method. Device comprises three-phase core-type transformer with flat laminated core, rods of which hold primary winding connected to AC circuit, and secondary winding is arranged in the form of short-circuited hollow chamber. Design feature is the fact that short-circuited chamber, which holds core with primary winding, is provided with two hollow water-washed electroconductive links passing through windows of core and welded to chamber walls. Since area of heat emission is considerably increased due to design of secondary winding, heat emitting surface of electric water heater increases, and accordingly, specific surface capacity reduces. Besides since links are cooled down, it makes it possible to avoid local heating of primary winding.

EFFECT: deterioration of conditions for formation of scale in process of liquid heating, longer service life of electric water heater without attendance, provides for maximum efficiency factor of device.

1 dwg

Description

The invention relates to electric heaters and is intended for hot water supply of residential buildings, industrial and agricultural enterprises.

The level of the invention is known from a device containing an integrated transformer with a lined core, a primary winding connected to the network, and a secondary, short-circuited, which has an arbitrary shape and is made of ferromagnetic sheet material with an electrically conductive coating (patent No. 20077895, H05B 6/10, publ. 02/15/94).

The disadvantage of this device is the difficulty of manufacturing a secondary winding, especially its electrically conductive coating, which leads to a rise in the cost of the device.

The closest in technical essence to the claimed invention is a transformer type electric heater, which has a flat charged magnetic core with a three-phase primary winding located on the magnetic core rods and a short-circuited secondary winding made in the form of a hollow chamber. To create short-circuited turns, the chamber is equipped with two electrically conductive jumpers welded to the walls of the chamber and used to close the phase currents of the secondary winding. These jumpers pass through the windows of the magnetic circuit. The jumpers are not washed with water, therefore they are made of a thicker sheet than the secondary winding. The chamber is equipped with a bottom and a lid, which together create a sealed enclosure that covers the inductor from water. The bottom and lid are welded to the camera body (US Pat. No. 22118675, H05B 6/10, publ. 10.12.03).

The disadvantage of this device is the small surface area of heat transfer, as well as the presence of jumpers not washed by water, which entails local overheating and a violation of the insulation of the primary winding.

The invention is aimed at increasing the heating efficiency, which consists in increasing the surface of the heat transfer and improving performance.

An electric water heater is proposed, which is a three-phase transformer with a flat lined magnetic circuit, on the rods of which a primary winding connected to an alternating current main is placed, and the secondary winding is made in the form of a short-circuited hollow chamber. A design feature is that the chamber, inside which the magnetic circuit with the primary winding is placed, is equipped with two hollow electrically conductive jumpers washed by water passing through the windows of the magnetic circuit and welded to the chamber walls. The design of the secondary winding together with short-circuit jumpers, bottom and cover create a sealed enclosure that is filled with an impregnating compound. Water is heated both in the flow mode and in the accumulation mode due to the power released in the secondary winding when current flows through it, as well as due to the allocated power in the primary winding, in the magnetic circuit and short-circuit jumpers made hollow, which increases the heat transfer area of the heating element with a minimum consumption of active materials and minimal dimensions.

The required technical result is achieved by increasing the heat transfer area of the heating element with a minimum consumption of active materials and minimal dimensions.

This is achieved by performing a secondary winding in the form of a short-circuited hollow chamber, inside of which an inductor is located (magnetic circuit with a primary winding). The inventive design of the secondary winding increases the heat transfer area of the heating element, increases the heating efficiency, improves performance.

The drawing shows the design of a transformer type electric heater with a flat lined magnetic core, the rods 1 of which are located in the same plane relative to each other and are connected by a yoke 2. On the rods 1 there is a three-phase primary winding 3. The secondary short-circuited winding is made in the form of a hollow chamber 4. Hollow short-circuited jumpers 5 located between the cores of the magnetic circuit are welded to the body of the chamber 4. The secondary winding together with the cover 6 and the bottom 7 create a sealed enclosure th shell, inside of which an inductor is placed (magnetic core with primary winding). The internal cavity of the chamber where the inductor is located is filled with an impregnating compound.

The device operates as follows. When the primary winding is connected to a three-phase network, an alternating current flows through it, creating a time-varying magnetic flux of the device’s magnetic system. This magnetic flux induces an electromotive force in the secondary winding, under the influence of which a three-phase alternating current flows in a short-circuited chamber. When current flows in the secondary winding, heat is transferred to the heated fluid.

Due to the fact that the heat transfer area is significantly increased due to the claimed design of the secondary winding, the heat transfer surface of the electric heater increases, and therefore, the specific surface power decreases, which leads to a deterioration in the conditions of scale formation during heating of the liquid, which means that it also provides a longer service life of the electric heater without maintenance . In addition, due to the fact that the jumpers are cooled, this avoids local overheating of the primary winding and ensures maximum efficiency of the device.

Claims (1)

A transformer-type electric heater containing a flat lined magnetic core with a three-phase primary winding connected to an alternating current network and a secondary winding in the form of a sealed chamber, inside of which electrically conductive jumpers are welded to the walls through the windows of the magnetic circuit, characterized in that the conductive jumpers are hollow and washed water.