RU2036756C1 - Welding transformer - Google Patents

Abstract

FIELD: electrical engineering. SUBSTANCE: transformer has located in safety shell single legged with side yokes magnetic circuit, primary winding, made of main and additional parts with adjusting taps, secondary winding with adjusting welded leads and two switches of primary winding: main power circuit voltage switch and adjusting taps switch. Primary winding big number of adjusting welded leads, made of thin enamel wire, increases productivity, expands limits of adjustment of welding current and provides conditions to use standard electrodes of different diameter. Making magnetic circuit single legged with side yokes and floor by floor concentric location of all the windings on one leg decreases consumption of materials and losses in structure. Converter provides transformer normal operation during significant deviations of main power circuit voltage. EFFECT: welding transformer is used in electrical engineering. 4 cl, 3 dwg

Description

 The invention relates to electrical engineering, namely to welding transformers used for arc welding, cutting and surfacing of metals in domestic and industrial conditions.

 Known welding transformer containing a two-core magnetic circuit, the primary and secondary windings, and the secondary winding consists of two parts, one of which is located on a separate rod and has adjusting tap.

 The disadvantage of this transformer is the low efficiency of the use of active materials due to the inability to ensure the constancy of the magnetic flux in different operating modes and, as a result, low profitability and high material consumption, as well as insufficient regulation range of the welding current.

Also known is a welding transformer containing a magnetic circuit, a high voltage winding (primary), a low voltage winding (secondary) and a switch, one of the windings (low voltage) being made of two parts with adjusting joints of the primary and secondary. The main part of this winding is located on one core of the magnetic circuit, and the additional part and the higher voltage winding on another rod. The switch is designed in such a way that the part of the turns of the main part of the winding is disconnected at the same time as the part of the turns of the additional part of the winding is connected [2]
In this transformer, the efficiency of using active materials in different operating modes has been significantly increased due to the regulation of electromagnetic coupling between the windings, the material consumption has been reduced, and the range of adjustable current has been increased.

 The disadvantages of the known transformer are low manufacturability due to the difficulty of performing a low voltage winding, designed for high current, of two parts with adjusting tapes (this winding is made of an increased bus cross section with a small number of turns), as well as low electromagnetic coupling between the windings located on different rods, which reduces the maximum value of the welding current and increases losses in the structure. In addition, this transformer is inoperative with deviations of the supply voltage from the nominal.

Also known is a welding transformer containing a single-core armored type magnetic core, primary and secondary windings located nearby along the rod, and the distance between the windings can be changed to change the reactance of the transformer and, accordingly, to ensure regulation of the welding current [3]
The disadvantages of this known transformer are: large material consumption due to the increase in the size of the magnetic circuit ("free space" on the rod is necessary to ensure mutual movement of the windings when regulating the welding current), increased design losses due to this, the complexity and unreliability of the mechanical drive for moving the windings and, accordingly, low manufacturability of the transformer. In addition, this transformer also reduces the reliability of operation while reducing the supply voltage.

 The technical result of the invention is an increase in manufacturability and reliability, an increase in the range of regulation of the welding current, a decrease in material consumption and losses in the design, as well as the possibility of use with significant deviations in the voltage of the supply network, achieved by performing the primary winding in two parts with the same control branches in the main and additional parts of the winding and with the switch, located next to the core of the main part of the primary and secondary windings, concentric p the location of the secondary winding and the additional part of the primary winding, as well as due to additional adjustment solders in the main part of the primary and secondary windings with the corresponding switches.

 In FIG. 1 shows a transformer, general view; in FIG. 2 active part of the transformer; in FIG. 3 circuit diagram.

 The transformer consists of a magnetic circuit 1, the main part of the primary winding 2 and the additional part of the primary winding 3, the secondary winding 4 and two switches of the primary winding: 5 switches for the voltage of the mains and 6 switches for the control branches. The magnetic circuit, windings and switches are placed in a protective casing 7, on which there are clamps 8 for connecting to the mains and clamps 9 for connecting output cables.

 The charged magnetic core 1 is made single-rod with side yokes. Lateral yokes have half the cross section than the rod. All windings are located on one rod. The main part 2 of the primary winding is made by a separate concentrate and occupies part of the length of the rod. The remainder of the length of the rod is occupied concentrically wound on top of each other, the additional part of the primary winding 3 and the secondary winding 4, and the secondary winding 4 is wound over part 3 of the primary winding. The primary winding is made, for example, of enamel wire and has two groups of adjusting branches. The first group is located at the beginning or at the end of the main part of the winding and output to switch 5. The second group is located at the end of the main part of the winding and in the additional part of the winding and output to switch 6. The first group of branches and switch 5 provide the connection of the transformer to the existing mains voltage, for example, 200, 220 or 240 V. The second group of branches and switch 6 provide stepwise regulation of the welding current. The number of turns at each stage of regulation is the same both in the main and in the additional part of the primary winding. The secondary winding 4 is made of insulated copper wire and may have additional solder 10 for regulating the welding current.

 The transformer operates as follows. Switch 5 is set to the position corresponding to the mains voltage, and switch 6 to the position corresponding to the minimum welding current. In this case, the voltage from the network is supplied to the beginning and end of the primary main winding, and all turns of the additional primary winding are turned off. This ensures a minimum value of the welding current due to the smallest magnetic coupling between the turns of the primary and secondary windings. The maximum welding current is achieved when the turns of the additional part of the primary winding are completely turned on and the adjustment turns of the main part of the primary winding are completely turned off. Intermediate values of the welding current are achieved at intermediate positions of the switch 6, when part of the adjustment coils of the main and the corresponding part of the coils of the additional primary winding are included. The numbers of turns are selected in such a way that they allow the use of a standard electrode with a diameter of 2, 2.5, etc. at each stage. up to 5 mm. Additional control of the welding current can be carried out using the solder 10 of the secondary winding.

 Performing adjusting seals on the primary winding from a relatively thin enamel wire is much more technologically advanced than on the secondary winding from the busbar. In addition, it is possible to increase the number of taps and, accordingly, the depth of regulation of the welding current. Additional adjustment of the welding current is provided by means of secondary windings. A clear stepwise regulation of the welding current allows the most efficient use of standard types of electrodes with a diameter of 2, 2.5, 3, 4 and 5 mm. The presence of an additional voltage switch allows the use of a transformer with a reduced mains voltage. The refusal of a mechanical drive to move the windings along the rod increases the reliability and manufacturability of the structure, the location of all windings on one rod without a significant gap between them reduces the material consumption of the transformer and losses in the structure. The total mass of the transformer according to the invention is 10-15% lower than that of the prototype transformer with an increased maximum welding current, control range and increased load duration.

Claims (4)

 1. WELDING TRANSFORMER containing a single-core armored type magnetic core, primary and secondary windings located adjacent to the rod, characterized in that the transformer is equipped with a tap changer and an additional winding connected in series with the primary winding, while the additional and primary windings are made with adjusting branches, the number of turns of all the adjusting branches are equal to each other, and the secondary and additional windings are arranged concentrically.  2. The transformer according to claim 1, characterized in that the secondary winding is wound concentrically on top of the additional winding.  3. The transformer according to claims 1 and 2, characterized in that the primary winding is equipped with additional adjustment tap located at the beginning of the winding, and an additional switch.  4. The transformer according to claims 1 to 3, characterized in that the secondary winding is provided with additional adjustment tapes.