Pumps of all types are not something that most of us give a second thought to, yet they affect so many areas of our life. Of course, these types of workings are 'under cover' and we don't normally have to concern ourselves with them. However, it does pay to understand a little about the processes that make our everyday life that little bit easier.

A vacuum pump is by no means a new design idea. For hundreds of years there have been various pumps for water and gases that have come and gone with varying success. As far back as 1206, an early predecessor to the vacuum pump came in the form of the suction pump, invented by an Arabic engineer. By the 15th Century the suction pump idea had reached Europe in the form of the six-cylinder Monobloc pump which could create a partial vacuum through a series of weights and pistons and this led on to other ideas.

By the 17th Century water pump designs were proving to be ideal as vacuum pumps but the concept was not understood and it took a series of engineers, scientists and inventors to realise the vacuum process and how it could overcome the previous hiccups of not being able to pump fluids above a certain height.
Galileo, Gaspar Berti and Evangelista Torricelli were all instrumental in the progression to vacuum pump technology.

The first true vacuum pump was created in 1654 by Otto von Guericke. He designed an experiment to prove that if the air was removed from a whole then there was no amount of power that could separate the two halves of that whole. This seemed to satisfy engineers and little more experimentation was carried out until 1855 when Heinrich Geissler took vacuum pumps to a new level with the mercury displacement pump.

Of course, since that time vacuum pumps have come on leaps and bounds, not least with the removal of highly toxic, carcinogenic materials, which always helps!
There are now three types of vacuum pump: the positive displacement pump which is the best for low vacuum needs; the momentum transfer pump, or molecular pump used with a displacement pump is the most common vacuum pump in use today; and the entrapment pump which is best used for ultra high vacuum needs over a short period of time.

Many applications of vacuum pumps consist of a series of all the above types of pumps to transport gases to where they need to be most efficiently and effectively. When exposed to high temperatures, other materials that are used in the construction of the pumps can give off gases that interfere with the whole mechanism, therefore they have to be monitored very carefully.
This is sometimes overcome by all the necessary components being baked at very high temperatures to ensure there are no more gases that could possibly leak.

High pressure vacuums are much more complex to arrange and often have to be custom built for each individual job. Usually constructed of stainless steel and baked under vacuum to stave off unwanted gasses.

There are many excellent uses for these types of pumps including medical processes such as radiotherapy, radiosurgery and radiopharmacy. Ophthalmic applications, glass coating, analytical instruments, the production of electric lamps, freeze drying and even sewage systems all use vacuum processes. They are also used frequently in engineering and motor engines.