Who invented the electric welding machine?

Who invented the electric welding machine? Forging welding technology appeared in Egypt more than 3000 BC. Over 2000 BC, the Yin Dynasty in China used casting and welding to make weapons. Before 200 BC, China had mastered the brazing of bronze and forging welding of iron. 180 1 year: the arc was discovered by H.Davy in Britain. Edmund David discovered acetylene gas. 1856: British physicist James Joule discovered the principle of resistance welding. 1959: DeVille and Debray invented hydrogen-oxygen welding. 188 1 year: the earliest carbon arc welding machine was invented by Demery Ence, a Frenchman. 188 1 year: it took Dr. R. H. Thurston of the United States six years to complete all the experiments on the strength and ductility of a full range of copper-zinc alloy solders. 1882: The austenitic manganese steel invented by Robert A. hadfield of England and named after him was patented. 1885: Elihu Thompson of the United States obtained the patent of resistance welding machine. 1885: carbon arc welding technology developed by Benardos Olszewski, Russia. 1888: Russian H. Cлавянов invented metal electrode arc welding. 1889 —— 1890: American C. L. Coffin used bare wires as electrodes for arc welding for the first time. 1890; American C. L. Coffin put forward the concept of welding in oxidizing medium. 1890: Englishman Brown tried to rob a bank for the first time by using oxygen and gas cutting. Working principle: It is a high-power transformer made of inductance principle, and it is a power supply (DC or AC) that changes 220V AC into low voltage and high current. When the inductor is turned on and off, it will produce a huge voltage change. The high voltage arc generated by the instantaneous short circuit between the positive and negative electrodes will be used to melt the solder on the covered electrode, so as to achieve the purpose of bonding. Welding transformer has its own characteristics, that is, the voltage drops sharply after covered electrode ignition. The working voltage of electric welding machine can be adjusted not only by a 220/380 voltage conversion, but also by the secondary winding tap. At the same time, it can be adjusted by iron core. Adjustable core welding machine is generally a high-power transformer.