How is the use of compressed air born? What is the first compressor ever to exist? What are the uses of compressed air over time? In the following article the answer to these and other questions.

The history of compressed air

In addition to electricity, compressed air is now the most used energy source in industry and crafts, but while you are already learning to use electricity as children, the importance, the possibilities and the advantages offered by compressed air continue to be unsatisfactory. The knowledge on compressed air has grown hand in hand with the knowledge of man in other technical applications. Their development throughout history took place only in those sectors in which it offered application advantages compared to other technologies. Compressed air has found application in any age, prompting men to reflect on the improvement of the techniques used.

The beginnings of compressed air

The first compressor: the lungs

Many technical applications are inspired and can be derived from the dawn of humanity. The first use of compressed air was to blow on baits to light the fire. The air used was compressed in the lungs, which can be considered a type of natural compressor. The capacity and performance of this compressor is amazing. The human lungs are capable of treating 100 l / min or 6 mᶾ of air per hour, generating a pressure of 0.02 - 0.08 bar. In the healthy state, the human compressor is unsurpassed in terms of its reliability and the costs for its maintenance are zero.

The improvement of the "lung"

However, the lungs proved insufficient when over 5000 years ago man began to melt metals such as gold, copper, tin and lead. When later it came to producing high-value metals such as iron from its minerals, the improvement of compressed air technology became indispensable. To obtain temperatures above 1000 ° C, more efficient lung aids were needed. At first the wind of fall was used from hills and mountain ridges. Later the Egyptian and Sumerian goldsmiths employed a puff cane. The air was blown directly onto the embers and this made it possible to increase the temperature significantly. Even today goldsmiths all over the world use a similar tool, which however is suitable for melting only small quantities of metal.

The first mechanical compressor, the hand-operated bellows

The first mechanical compressor, the manually operated bellows, was developed around 2500 years before the birth of Christ. Development was necessary when the copper and tin alloy technology for bronze production developed into a stable production method. The invention can be observed in a mural painting in a tomb of ancient Egypt. This constituted the birth of compressed air in the modern sense.

First applications of compressed air, recognition of the properties of compressed air

Hydraulic organ

The first conscious use of the force inherent in the air was handed down to us by the Greek Ctesibio (around 285 - 222 BC). He built a hydraulic organ and used compressed air to store and dampen the pulse.

Catapult, energy storage

Another characteristic of compressed air, energy storage, was exploited by Ctesibio for its catapult, which generated the voltage necessary to hurl projectiles by means of compressed air into a cylinder.

Temple doors

Heron lived in Alexandria in the first century BC. I invent a device that can automatically open the doors of a temple, as long as the fire burned on the altar inside the building. The secret was to expand the hot air that pushed the water from one container to another. The possibility of doing work by changing the state of the air was recognized by Heron unconsciously.

Pascal's principle

Only in the 17th century did a group of scholars begin to deal with the laws governing the behavior of compressed air. In 1663 Blaise Pascal published his studies on the amplification of force through liquids (hydraulics) also applicable to compressed air technology. Pascal observed that the force of a man acting on an opening a hundred times the size of the opening produced a force of 100 men.

Transport of bodies through pipes

Referring to Heron, the French physicist Denis Papin described in 1667 the possibility of transporting bodies through pipes using the small pressure difference inside a pipe. He found that forces were generated on a body that was in this tube. With this was recognized the advantage offered by the higher working speeds resulting from the air. Thus Papin founded the pneumatic conveying technique.

Pneumatic brakes

Already around 1810 the railways were operated with compressed air. In 1869 Westinghouse introduced its pneumatic air brake. Three years later he followed his brake training device. In this system, the brakes were trained to overpressure, that is, to pressure drop, thus achieving the maximum braking effect. For the first time the possibility offered by "fail safe" behavior was exploited, a braking system operating on this principle is also used today for trucks.

Pneumatic post

The idea of ​​compressed air railways was not forgotten. In 1863 Latimer Clark, together with the engineer Rammel, built a small pneumatic railway in London. The small wagons traveled closed in a tube and were intended for the transport of postal bags and packages. This railway was much more versatile than the heavy atmospheric railways of 1810 and eventually led to the development of pneumatic post. Pneumatic post networks were subsequently built in Berlin, New York and Paris. The Parisian network reached its maximum extension in 1934 with a total length of 437 Km. Even today pneumatic tube continues to be used in large industrial companies.

Pneumatic tools

In the construction of the Moncenisio tunnel of the year 1857 the new technique of compressed air perforating hammers for the rock was used. Starting from 1861, percussion drilling machines with pneumatic drive were used for tunnel advancement, powered by compressors located on the two inlets. In both cases the compressed air was transported for long distances. When the tunnel was completed in 1871, more than 7000 m of pipes had been installed on both sides. For the first time, the transportability of energy and its advantages were demonstrated and made known to a large audience. This led to increasingly efficient and versatile pneumatic tools.

Pneumatic networks, centralized generation of compressed air and signal transmission

The experience gained in the use of pneumatic pipe networks and the development of more powerful compressors led to the installation in Paris of a pneumatic network in the discharge channels which in 1888 was put into service with a total power of the compressors equal to 1500 kW. In the year 1891, the installed power was already 18 000 kW. The vast success of the pneumatic network derived, among other things, from the invention of a clock which was advanced every minute by an impulse transmitted by the compression station. Then it was recognized not only the possibility of transporting energy, but also of the transport of signals over large distances in a pneumatic network. The Parisian pneumatic network is unique to this day and is still in operation.

Signal Processing, Compressed Air for Signal Transmission and Processing

In the 50s of the 20th century, the high flow rate of compressed air for signal processing and transmission was discovered in the USA. The very low pressure pneumatics, also called fluidics or pneumatics (pneumatic logic), allows to integrate in very small spaces logical functions in the form of fluid-mechanical elements operating at the pressure of 1.001 - 1.1 bar. The high operational safety of the fluidic logic elements in extreme environmental conditions has allowed their use in the astronautics and military technology of the USA and the former Soviet Union. In particular, their immunity to electromagnetic radiation emitted by the explosion of thermonuclear bombs gives fluidics significant advantages in some highly sensitive sectors. However, fluidics has been replaced almost completely over time by electronics and microelectronics in the areas of signal transmission and information processing.

By BuyFilterOnline.com