28 April - Saturday

World Day for Safety and Health at Work
International Day of Veterinarian
Day of Ambulance Workers
World Day of Tai Chi and Qigong

1563 The printing house of the first printers Ivan Fedorov and Peter Mstislavets began to work in Moscow
1914 In the US, an air conditioner is patented
2001 The first space tourist flies into space

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April 28, 1914 in the US was patented air conditioner. The conditioner is designed to maintain the desired temperature and humidity in the room. Ventilating the air, it clears it, passing the air flow through special filters.
For the first time about the air-conditioner, as an invention, it became known in 1815, when the Frenchman Jeanne Scabannes patented the method of conditioning the air flow and a way of regulating the temperature in buildings. Despite the perspective idea of ​​air conditioning of the premises, its practical application had to wait a long time.
Only in 1902 in the US, inventor engineer Willis Carrier assembled the world's first industrial refrigeration machine for a printing plant in New York. And this first climatic technique, which is the ancestor of the air conditioner, was not designed to create a pleasant coolness for workers, but to combat humidity, which greatly worsened the quality of printing.
Realizing all the advantages of this technique, soon began the widespread installation of air conditioners in theaters and shops. Despite the high cost of this installation, practical Americans did not spare money, as the comfortable coolness in the rooms, which the air conditioner created even in the hottest months, very effectively attracted visitors.
Excellent orientated and American machinery manufacturers. For example, the American company "General Electric", having released in 1929 the first room air conditioner, became the ancestor of all modern air conditioners and for a long time was fixed in the list of leaders in the manufacture of air conditioning systems. Since ammonia was used as the refrigerant in this device, the vapors of which are unsafe for humans, the compressor and the condenser of the air conditioner were taken to the street.
Since 1931, when a freon safe for the human body was invented, the designers assembled all the units and units of the air conditioner in one housing. So there were the first window conditioners, whose distant descendants successfully work today.
Although American companies have tried to be leaders in the field of air-conditioning systems, since the late 1950s, they have gradually been replaced by Japanese companies. It was the Japanese who were the first to make split-systems (air-conditioners divided into external and internal units).
Over time, air conditioners became more powerful and functional, their service life increased. Modern air conditioners except air cooling (the main purpose of their use) can also heat air, ionize, drain, ventilate and purify, increase the oxygen content in the air.