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Engineer and inventor James Watt

Foto. Ватт Джеймс

January 19 marks 270 years since the birth of James Watt (1736-1819), English inventor, whose name is called watt power unit. Improvement of the steam engine made by Watt, was one of the most outstanding events in the history of technology. It was one of those inventions, that marked the beginning of the industrial revolution in England in the second half of the XVII century.

Biography of James Watt's is extremely interesting and instructive. It can be a model biography of the great engineer, who not just only invent something, but also bring the matter to the production and wide use of his invention.

Steam engine

James Watt was born in the small Scottish town of Greenock. His father built houses and ships, and had also a workshop where various tools were made. Little James Watt was a weak child. Although he early went to the free primary school, he often stayed at home because of illness. He independently acquired good knowledge of the physical and mathematical sciences. Special impression on him was made by the book Dutch scientist Gravezand "Basic Principles of Physics", written under the influence of the ideas of Newton. He learned to use various tools in the parent’s workshop.

When Watt was 18, the parents decided to send him to study at the mechanics - so then called the master, who manufactured precise mathematical, geophysical and general physical devices. In the summer of 1754, James Watt went to learn the craft in Glasgow, where he lived with his uncle Muirhead, a professor of ancient languages Glasgow University. He stayed for a year apprentice in a studio, but it became clear that a thorough training to get there impossible. Thanks uncle Watt met with several university professors, then it was very handy.

With the consent of the father, Watt traveled to London. It turned out that here to become a master, according to the laws of the guild, it was necessary to be a student for seven years and to pay a significant amount of the fees. James managed to find a free place at one watchmaker, who taught him also the engraving. After a while, Watts entered apprentice in the studio with John Morgan for one year from the tuition fees of £ 20. Because of hard time in his father’s business, the young Watt lived very frugally, looking for additional income. But despite this, Watts showed great desire to master the craft. Starting with a simple execution of works, after one year he can produce such sophisticated tool as reflecting sextant.

At the end of 1756 Watt went to Glasgow, where he wanted to open his own workshop for the production of mathematical tools, but did not obtain a permission. Fortunately, with the help of his friends professors he managed to become of the University of Glasgow mechanic. Work at the university, of course, was of decisive importance for the Watt’s future and the history of technology. In particular, Watt met the famous physicist and chemist Dzh.Black who discovered the so-called latent heat of vaporization. Watt also made friends with many students. Known professor Robizon recalled how as a student, he met with Watt and was impressed by his knowledge. Students met with difficulties, often turned to the young mechanic for advice. Watt, if he could not answer them, began to study the question. To read one of the first papers devoted to machines, Watts studied German, then in a similar occasion - Italian.


Watt became engaged with a steam engine after a winter of 1763-1764 when he refurbished model of Newcomen steam engine owned by the Faculty of Natural Philosophy Glasgow University.

Newcomen steam engine was invented in 1711 and over time has been widely used for pumping water from coal mines. Advanced machine Newcomen proceeded as follows. In the cauldron a water is boiling. Above the boiler a cylinder machine was mounted, attached to the beam of the house. When the piston is raised, the steam goes into the cylinder. After reaching the upper position of the piston, the supply of steam was closed, and cold water was injected into the cylinder. Condensed steam was evacuated, and due to atmospheric pressure piston moves down - it was the used movement of the machine.

When Watt repaired machine model Newcomen, it turned out that she needs the injection of excessive amounts of cold water. Intrigued by this phenomenon, Watts began extensive research. He concluded that the poor performance of the model in comparison with the real Newcomen machine due to the condensation of fresh steam at the inlet of the cylinder. He conducted experiments in which he studied the basic properties of the steam: finding the relationship between pressure and temperature, determining the specific volume of steam, the latent heat of vaporization. After that he was looking for a means to reduce the initial condensation. He decided that in order to make better use of steam is necessary that the cylinder had a temperature of steam entering into it, and was not cooled. Accordingly, Watt invented the steam to condense in a separate refrigerator. It should be noted that by conducting experiments, Watt consulted with Dzh.Black.

In addition to the separate refrigerator, Watt made some other improvements: proposed for piston seals use wax or grease, close the cylinder top cover, with the round rod. In addition, proposed to stud the cylinder with wood or other insulation.

Realization of invention

In 1765, Watt was building the bigger and bigger models of his machine. He convinced in his decision, but to continue the studies he lacked the funds. The friends, especially Black, tried to help Watt, organizing support from some capitalist. First Watt was helped by Black’s friend Doctor Rebuk - a famous chemist and businessman.

The agreement, which entered into Watts and Rebuk, provided that the latter will receive two thirds of the profits derived from the use of the steam engine. Instead, he pledged to fund experiments with the car and pay for a patent. January 5, 1769 Watt received a patent for "a method of reducing steam consumption and thereby - in full fire engines." The patent was granted for 14 years. It started production of large machines, but then business of Rebuk was deteriorated and work stopped.

It should be noted that in 1768 Dj.Watt met with an outstanding engineer and entrepreneur M. Bolton – the owner of a metalworking factory in Birmingham - and wanted to bring him in as a third party, but Bolton refused. With Rebuk’s bankruptcy in 1773, Watt’s machine and the right to future income were taken over by the receivership creditors and Bolton bought them. However, he made an agreement with Watts on the same terms and conditions as Rebuk: assumed the costs associated with the experience and manufacturer of the steam engine, as well as the business side of the enterprise. Watts also undertook to conduct further research and design of the machine.

In 1774 Watt moved to Birmingham and from that time the most fruitful period of his activity begun - implementation of an initial draft of water-lifting machines and a new type of machine - especially for factory use.

First some details were altered, then there build and run the machine made in the factory Rebuk with the cylinder diameter of 18 inches (457 mm) and stroke 5 feet (1.5 m). Tests have shown that this machine is in the 3-4.5 times more economical than the Newcomen machine.

But before the organization of the production of machinery, Watt and Bolton took care of patent term extension. This issue was considered by the Parliament, which extended the patent for 25 years, up to 1800

They began to receive orders for the car. In 1780 Watt built 40 cars, half of which were installed in the copper mines in Kornuels. Bolton did business at the plant, and Watts had a lot of time to spend in Kornuels - engaged in the installation of machines, their start-up, testing, financial calculations with the owners of the mines. First, the production did not give profit: the organization of production demanded of fixed costs. In addition, the owners of the mines did not pay for the patent in time. Against defaulters the cases were opened. However, as it is customary in England, they carried out very slowly and required costs. Only in the 1786-1787 the business started to be better, in particular, they have won the case against the owners of the mines on wages.

There were other difficulties. In particular, the plant does not have enough quality workers. Due to the lack of qualified assistants Watt himself conducted experiments was drawings and set their machines. Over time, the plant has developed a "normal" type of water-lifting machines simple actions (see. Figure), which was used for pumping water.

Improvement of the steam engine

The first and one of the most important improvements of the steam engine was the use of steam expansion, steam in the cylinder was not delivered in the full stroke of the piston. The patent for this invention Watt took in 1782. In the description of the invention Watts pointed to a quarter of the stroke as a profitable duration of the steam inlet.

To use the steam engine for driving the bench, it was necessary to transform the vibrational movement of the balancer shaft in continuous rotation. This is most easily can be realized by applying the rod to the crank. But in 1780, some Picard took out a patent on the use of a crank in the "fire engines". Therefore, Watts founded other ways to solve the problem, in particular, has invented a mechanism so-called "solar and planetary wheel", which was used in the machines Watt until the Picard patent expiry.

Next Watt took out a patent on the machine dual action in which a pair of pressed on the piston alternately on both sides. But the creation of a double-acting machines required changing the way the force transmission from the piston to the rocker: chain drive, which was used previously could not transmit compressive forces. Then Watt created the so-called parallelogram Watt.

The machine, which is designed to actuate the bench should have a high uniformity of stroke. To achieve this, the Watt invented automatic control regulator coupled to the throttle valve.

Subsequently, he made many other innovations - applied mercury manometer to measure the pressure in the boiler, water-glass in boilers, Vacuum gauge mercury in the condenser. Also made many other inventions.

Subsequently merits Watt became generally accepted. In 1784 he was elected a member of the Royal Society of Edinburgh, in 1785 - London, and in 1814 - The Paris Academy of Sciences.

James Watt died Aug. 19, 1819.


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