1 and 1873, German chemist and engineer Karl von Linde invented a refrigerator with ammonia as refrigerant. Linde uses a small steam engine to drive the compression system, so that ammonia can be repeatedly compressed and evaporated to produce refrigeration. Linde first applied his invention to Sai Doummar Brewery in Wiesbaden, and designed and manufactured an industrial refrigerator. Later, he improved the industrial refrigerator. Miniaturizing it, the world's first domestic refrigerator with artificial refrigeration was made in 1879. This kind of steam-driven refrigerator was put into production soon, and 189 1, 12000 units have been sold in Germany and the United States.
2. The first refrigerator with motor-driven compressor was invented by Swedish engineers Brighton and Mendes in 1923. Later, an American company bought their patent and produced the first batch of household refrigerators at 1925. In the first refrigerator, the electric compressor and the refrigerator were separated, and the latter was usually placed in the cellar or storage room of the family and connected with the electric compressor through pipes, and then they were combined into one.