James watt, a British instrument repairman, invented the steam engine with the condenser separated from the cylinder wall in 1765, and obtained the British patent in 1769. The appearance of the steam engine caused the industrial revolution in the18th century. Until the beginning of the 20th century, it was still the most important prime mover in the world, and then it gradually gave way to internal combustion engines and steam turbines.
Steam locomotive
Sun Qijun, an Englishman, invented the steam locomotive.
electric motor
1834 jacoby, Germany, invented the DC engine. 1834, it became a simple device: a six-arm wheel was installed between two U-shaped electromagnets, and two bar magnets were installed on each arm. After electrifying, the mutual attraction and repulsion between the bar magnet and the U-shaped magnet drives the axle to rotate. Later, jacoby made a big device. Installed on a small boat, powered by a 320-Daniel battery, the boat sailed on the Elbe River for the first time in 1838, with a speed of only 2.2 kilometers per hour. At the same time, Davenport of the United States has also successfully built a motor to drive the printing machine, printing electromagnetic and mechanical information, a sentence of the American electricity semester. However, these two kinds of motors are of little commercial value, and it is too expensive and impractical to use batteries as power supply.
4.？ electric light
? 1850, the Englishman Joseph Wilson Swan began to study electric lights. 1878, he obtained a British patent for a light bulb powered by carbon wire under vacuum, and started to set up a company in Britain to install electric lights in every household.
5. Generator
In A.D. 183 1 year, Faraday passed a wire in a closed circuit through an electromagnetic field. When the wire rotates, a current will flow through the wire, so Faraday realized that there is a close relationship between electricity and magnetic field. He built the first prototype generator, including a copper disk rotating in the magnetic field, and this generator generated electricity. Before that, all the electricity was generated by electrostatic machines and batteries, and they could not generate much power. However, Faraday's generator finally changed everything.
The generator includes an electromagnet that can rotate rapidly between two or more magnetic fields. When two magnetic fields cross each other, electricity is generated, which is led out of the generator by wires. Electronic engineers get alternating current (AC) or direct current (DC) according to the winding mode of the generator and the arrangement of magnets. Most generators generate alternating current, which is easier to transmit over long distances through transmission lines than direct current.