Noun
vacuum pump (plural vacuum pumps)
A piece of equipment used for extraction of gas or vapour from an enclosed space, leaving the container with a partial vacuum.
A vacuum pump is turned on, and air pressure pushes down on the coversheet to hold the material in place. Source: Internet
Early thermodynamics A precursor of the engine was designed by the German scientist Otto von Guericke who, in 1650, designed and built the world's first vacuum pump and created the world's first ever vacuum known as the Magdeburg hemispheres experiment. Source: Internet
History Tesla's vacuum apparatus, published in 1892 The predecessor to the vacuum pump was the suction pump, which was known to the Romans. Source: Internet
Many inexpensive low vacuum gauges have a margin of error and may report a vacuum of 0 Torr but in practice this generally requires a two-stage rotary vane or other medium type of vacuum pump to go much beyond (lower than) 1 torr. Source: Internet
Second the positive displacement pump backs up the momentum transfer pump by evacuating to low vacuum the accumulation of displaced molecules in the high vacuum pump. Source: Internet
For example, air begins to absorb significantly around the 193 nm wavelength; moving to sub-193 nm wavelengths would require installing vacuum pump and purge equipment on the lithography tools (a significant challenge). Source: Internet