| 摘要 |
FIELD: equipment for electric arc welding of metals and alloys by pulse welding current, possibly in different branches of industry. ^ SUBSTANCE: method comprises steps of conversion of voltage of electric power source to voltage in the form of different-polarity rectangular pulses having repetition frequency of ultrasound band. Voltage is converted by means of high-frequency pulse type transformer with drooping voltage-current characteristic and by means of high-frequency rectifier to welding electric current in the form of unipolar rectangular pulses with repetition frequency of ultrasound band whose rise and drop are accompanied with high-frequency damping modulation. Modulation is realized due to action of different-polarity rectangular pulses upon high-frequency pulse type transformer whose resonance frequencies are used for exciting high-frequency large-amplitude oscillations. Drooping voltage-current characteristic of high-frequency pulse-type transformer and of welding current is provided due to special design of transformer and special setting of pulse duration, pauses between pulses and speeds of rise and drop of pulses. Apparatus for electric arc welding includes high-frequency converter of voltage of electric power source to different-polarity rectangular pulses; high-frequency pulse type transformer with drooping voltage-current characteristic and high-frequency rectifier for supplying welding current directly to welding electrode. ^ EFFECT: enhanced quality of welded joints due to stable arc burning, significantly increased operational reliability of welding equipment comparable with that of transformer type welding current sources, lowered mass and size of apparatus. ^ 20 cl, 4 dwg |
