Vacuum engineering
Vacuum technology is a method used to evacuate air from a closed volume by creating a pressure differential from the closed volume to some vent, the ultimate vent being the open atmosphere. When using an industrial vacuum system, a vacuum pump or generator creates this pressure differential. A variety of technical inventions were created based on the idea of vacuum discovered during the 17th century. These range from vacuum generation pumps to X-ray tubes, which were later introduced to the medical field for use as sources of X-ray radiation. The vacuum environment has come to play an important role in scientific research as new discoveries are being made by looking back to the basic fundamentals of pressure. The idea of “perfect vacuum” cannot be realized, but very nearly approximated by the technological discoveries of the early 20th century. Vacuum engineering today uses a range of different material, from aluminum to zirconium and just about everything in between. There may be the popular belief that vacuum technology deals only with valves, flanges, and other vacuum components, but novel scientific discoveries are often made with the assistance of these traditional vacuum technologies, especially in the realm of high-tech. Vacuum engineering is used for compound semiconductors, power devices, memory logic, and photovoltaics.
History of the automobile
The vintage era lasted from the end of World War I (1918), through to the Wall Street Crash at the end of 1929. During this period the front-engined car came to dominate with closed bodies and standardised controls becoming the norm. In 1919, 90% of cars sold were open; by 1929, 90% were closed. Development of the internal combustion engine continued at a rapid pace, with multi-valve and overhead camshaft engines produced at the high end, and V8, V12, and even V16 engines conceived for the ultra-rich. Also in 1919, hydraulic brakes were invented by Malcolm Loughead (co-founder of Lockheed); they were adopted by Duesenberg for their 1921 Model A. Three years later, Hermann Rieseler of Vulcan Motor invented the first automatic transmission, which had two-speed planetary gearbox, torque converter, and lockup clutch; it never entered production. (Its like would only become an available option in 1940.) Just at the end of the vintage era, tempered glass (now standard equipment in side windows) was invented in France. In this era the revolutionary ponton design of cars without fully articulated fenders, running boards and other non-compact ledge elements was introduced in small series but mass production of such cars was started much later (after WWII).