Device that converts motion into electricity

Dynamo

Dynamo Electric Machine [End View, Partly Section] (U.S. Patent 284,110)

The Dynamo was the first electrical generator capable of delivering power for industry. The dynamo uses electromagnetic principles to convert mechanical rotation into a pulsing direct electric current through the use of a commutator. The first dynamo was built by Hippolyte Pixii in 1832.
Through a series of accidental discoveries, the dynamo became the source of many later inventions, including the DC electric motor, the AC alternator, the AC synchronous motor, and the rotary converter.
A dynamo machine consists of a stationary structure, which provides a constant magnetic field, and a set of rotating windings which turn within that field. On small machines the constant magnetic field may be provided by one or more permanent magnets; larger machines have the constant magnetic field provided by one or more electromagnets, which are usually called field coils.
Large power generation dynamos are now rarely seen due to the now nearly universal use of alternating current for power distribution and solid state electronic AC to DC power conversion. But before the principles of AC were discovered, very large direct-current dynamos were the only means of power generation and distribution. Now power generation dynamos are mostly a curiosity.

Invention of an Electric Motor

As is so often the case with invention, the credit for development of the electric motor belongs to more than one individual. It was through a process of development and discovery beginning with Hans Oersted's discovery of electromagnetism in 1820 and involving additional work by William Sturgeon, Joseph Henry, Andre Marie Ampere, Michael Faraday, Thomas Davenport and a few others.
The first electric motors - Michael Faraday, 1821From the Quarterly Journal of Science, Vol XII, 1821
Using a broad definition of "motor" as meaning any apparatus that converts electrical energy into motion, most sources cite Faraday as developing the first electric motors, in 1821. They were useful as demonstration devices, but that is about all, and most people wouldn't recognize them as anything resembling a modern electric motor. There are several Faraday motors in the collection.
Faraday Motor from the collection1830's
The motors were constructed of a metal wire suspended in a cup of mercury (See illustration at right). Protruding up from the bottom of the cup was a permanent magnet. In the left cup the magnet was attached to the bottom with a piece of thread and left free to move, while the metal wire was immobile. On the right side, the magnet was held immobile and the suspended wire was free to move.
When current from a Volta pile was applied to the wire, the circuit was completed via the mercury ( a good conductor of electricity) and the resulting current flowing through the wire produced a magnetic field. The electromagnetic field interacted with the existing magnetic field from the permanent magnet, causing rotation of the magnet on the left, or of the wire on the right.

Great inventors of 18 th century

The 18th century is the time of many changes (political, industrial, cultural). Also physics developed fast. Scientists used Newton's laws to describe their discoveries, but they also created new theories and laws for better understanding of nature. Scientists did a research in chemistry. It's also the time of researching electricity. Occurrences of electricity were known even in ancient times (Thales described the electrical influence of amber electrified by rubbing) but it wasn't thoroughly researched till 18th century. All that led to better understanding of laws of microstructure. Scientists, no more hesitating, were using data from experiments and for many, experiments became the most important scientific instrument.
Stephen Gray (1670-1736), discovered that electrical current can be moved from one place to another by different metals and moist fibres. That substances cannot be electrified by rubbing. He called them "conductors". Gray's investigation proved that electricity is not similar to Gilbert's "fluid", because it is not connected with the substance for long periods.
Dufay in 1733 discovered, that there are two kinds of electricity. He noticed that a gold plate electrified by a piece of glass rubbed with silk would be repulsed by glass and attracted by a resinous substance - copal rubbed with fur. Than Dufay found many other substances behaving like glass or copal when touched by the electrified gold plate. So he named that two kinds of electricity the "glass" one and the "resinous" one.
Daniel Bernoulli (1700-1782), starting with the idea of atom, proved Boyle's law, assuming that the pressure of a gas consists of atoms colliding with the walls of the container filled with this gas.. It was the first time when the hypothesis of atom were used in quantitatively and experimentally verifiable calculations.
Benjamin Franklin (1706-1790), worked on the problems of electricity. He introduced the idea of the positive and negative electricity. He maintained that electrifying bodies consist of electricity's flow. He formulated the electric charge's conservation law. He explained electrostatic induction.
Rudjer Josip Boscowich who was born in 1711 in Dubrovnik and died in 1787, created some interesting theories about world's microstructure. Although he knew Newton's works he didn't accept the law of universal gravity completely. He thought, that it might not be the rule in atomic scale, where attractive force could be always equilibrated by the repulsive force. He postulated the existence of a field of force which could be described using geometry. He also said that atoms were particles without any dimensions, they were reduced to geometric points.
Charles Augustin de Coulomb (1736-1806), worked on problems of electrostatics and magnetism. He created torsion balance. Thanks to it he could precisely evaluate forces. He showed that forces between charges are inversely proportional to the square of the distance between them. He also discovered that identical charges repulse and different charges attract.
Antoine Laurent Lavoisier was the great French chemist, who lived between 1743 and 1794. Chemistry as a science, at the beginning of the 18th century, was an assembly of different, chaotic rules. The same was with chemical nomenclature. Lavoisier arranged chemical nomenclature based on the names of simple substances while giving names to complicated substances composed of this simple ones. But before he could systematise chemical nomenclature he had to make changes in chemistry. He proved that all elements could occur in three states of aggregation: gaseous, liquid and solid. He showed that during burning, substances combine with oxygen. He also proved that water could not change into other substances like many scientists thought. He thought that precipitate left after boiling water, didn't come from the water but from the pot. After longer research he managed to prove that water consisted of oxygen and hydrogen. Decomposing water he discovered that the weight ratio between oxygen and hydrogen was always 8:1. It was a direction indicating that world consisted of atoms. Lavoisier believed in it, but he didn't developed his study of atom. He arranged chemistry in such a way, that the next scientists could easier fathom its mysteries and penetrate chemical secrets.
Alessandro Volta (1745-1827), was the originator of the first galvanic cell (in 1800). It was made of zinc and silver electrodes immersed in sea water. He built also an electrometer to measure currents.
John Dalton (1766-1844) was the first chemist who in explaining different phenomena used the theory of study of atom. He researched gases. He discovered the law of partial pressures. Dalton's law says that pressure of nonreactive gaseous mixture is equal to a sum of pressures of each, separate element of the mixture having the same volume as the mixture has. Another Dalton's discovery, which he made in 1804, was showing that, if two elements have more than one combination, then weight amounts of one of them belonging to unchanging amount of the second one are staying in relations of small integers (the law of stoichiometry). For example, for chlorine oxides (Cl2O, Cl2O6, Cl2O7) masses of oxygen belonging to chlorine unit are staying in proportions 1:6:7. Dalton noticed that results he got could be simply explained using the conception of atom. Expanding study of atom ideas he assumed that chemical combinations were created by combining the atoms of different elements. He was of the opinion that atoms of different elements had different masses, as mass unit he took the mass of one atom of hydrogen. He laid the foundation of modern study of atom and he described world's microstructure explaining most of occurrences known those days. After over two thousand years, finally there were so many proofs of atom's existence, that hypothetical till then, atoms became real (although Dalton's particles were not the same as Democritus's ones because it appeared they were not final components of matter).
Research on atom, which took place in 18th century brought many answers but also many questions. Finally, thanks to Dalton's works there was enough proof of atom's existence that it became a publicly admitted scientific concept. It also appeared that there were two kinds of molecules - the positive ones and the negative ones. Some secrets of electricity were explained but mostly it was still a puzzle, which scientists tried to solve in the next century.

Great Inventors

Michael Faraday (1791-1867) British physicist and chemist, best known for his discoveries of electromagnetic induction and of the laws of electrolysis. His biggest breakthrough in electricity was his invention of the electric motor.
Born in 1791 to a poor family in London, Michael Faraday was extremely curious, questioning everything. He felt an urgent need to know more. At age 13, he became an errand boy for a bookbinding shop in London. He read every book that he bound, and decided that one day he would write a book of his own. He became interested in the concept of energy, specifically force. Because of his early reading and experiments with the idea of force, he was able to make important discoveries in electricity later in life. He eventually became a chemist and physicist.
Michael Faraday built two devices to produce what he called electromagnetic rotation: that is a continuous circular motion from the circular magnetic force around a wire. Ten years later, in 1831, he began his great series of experiments in which he discovered electromagnetic induction. These experiments form the basis of modern electromagnetic technology.
In 1831, using his "induction ring", Michael Faraday made one of his greatest discoveries - electromagnetic induction: the "induction" or generation of electricity in a wire by means of the electromagnetic effect of a current in another wire. The induction ring was the first electric transformer. In a second series of experiments in September he discovered magneto-electric induction: the production of a steady electric current. To do this, Faraday attached two wires through a sliding contact to a copper disc. By rotating the disc between the poles of a horseshoe magnet he obtained a continuous direct current. This was the first generator. From his experiments came devices that led to the modern electric motor, generator and transformer.
Michael Faraday continued his electrical experiments. In 1832, he proved that the electricity induced from a magnet, voltaic electricity produced by a battery, and static electricity were all the same. He also did significant work in electrochemistry, stating the First and Second Laws of Electrolysis. This laid the basis for electrochemistry, another great modern industry.

Invention of KinetoScope

Thomas Edison's interest in motion pictures began before 1888, however, the visit of Eadweard Muybridge to his laboratory in West Orange in February of that year certainly stimulated his resolve to invent a camera for motion pictures. Muybridge proposed that they collaborate and combine the Zoopraxiscope with the Edison phonograph. Although apparently intrigued, Edison decided not to participate in such a partnership, perhaps realizing that the Zoopraxiscope was not a very practical or efficient way of recording motion. In an attempt to protect his future, he filed a caveat with the Patents Office on October 17, 1888, describing his ideas for a device which would "do for the eye what the phonograph does for the ear" -- record and reproduce objects in motion. He called it a "Kinetoscope," using the Greek words "kineto" meaning "movement" and "scopos" meaning "to watch."
One of Edison's first motion picture and the first motion picture ever copyrighted showed his employee Fred Ott pretending to sneeze. One problem was that a good film for motion pictures was not available. In 1893, Eastman Kodak began supplying motion picture film stock, making it possible for Edison to step up the production of new motion pictures. He built a motion picture production studio in New Jersey. The studio had a roof that could be opened to let in daylight, and the entire building was constructed so that it could be moved to stay in line with the sun.
C. Francis Jenkins and Thomas Armat invented a film projector called the Vitascope and asked Edison to supply the films and manufacture the projector under his name. Eventually, the Edison Company developed its own projector, known as the Projectoscope, and stopped marketing the Vitascope. The first motion pictures shown in a "movie theater" in America were presented to audiences on April 23, 1896, in New York City.

Invention of lamp

The incandescent lamp together with the central power station, may be regarded as milestones in the history of applied electricity. It comprised a complete generating, distributing, and utilizing system, from the dynamo to the very lamp at the fixture level, ready for use. It even included meters to determine the current actually consumed.
The success of the system was complete, and as fast as lamps and generators could be produced they were installed to give a service at once recognized as superior to any other form of lighting. By 1885, the Edison lighting system was commercially developed, though still subject to many improvements and capable of great enlargement. However, Thomas Edison sold the company and turned his great mind to other inventions

Invention of Electricity

Invention Of Electricity was not an overnight event. The Invention Of Electricity can be seen as far back as 600 B.C. in the writings of Thales of Miletus when it appears that Westerners knew back then that amber becomes charged by rubbing. There was little real progress in the Invention Of Electricity until the English scientist William Gilbert in 1600 described the electrification of many substances and coined the term electricity from the Greek word for amber. As a result, Gilbert is called the father of modern electricity. In 1660 Otto von Guericke invented a crude machine for producing static electricity. It was a ball of sulfur, rotated by a crank with one hand and rubbed with the other. Successors, such as Francis Hauksbee, made improvements that provided experimenters with a ready source of static electricity. Today’s highly developed descendant of these early machines is the Van de Graaf generator, which is sometimes used as a particle accelerator. Robert Boyle realized that attraction and repulsion were mutual and that electric force was transmitted through a vacuum. Stephen Gray distinguished between conductors and nonconductors. C. F. Du Fay recognized two kinds of electricity, which Benjamin Franklin and Ebenezer Kinnersley of Philadelphia later named positive and negative.Progress in the Invention Of Electricity quickened after the Leyden jar was invented in 1745 by Pieter van Musschenbroek. The Leyden jar stored static electricity, which could be discharged all at once. In 1747 William Watson discharged a Leyden jar through a circuit, and comprehension of the current and circuit started a new field of experimentation. Henry Cavendish, by measuring the conductivity of materials (he compared the simultaneous shocks he received by discharging Leyden jars through the materials), and Charles A. Coulomb, by expressing mathematically the attraction of electrified bodies, began the quantitative study of electricity.A new interest in the Invention Of Electricity and electric current began with the invention of the battery. Luigi Galvani had noticed (1786) that a discharge of static electricity made a frog’s leg jerk. Consequent experimentation produced what was a simple electron cell using the fluids of the leg as an electrolyte and the muscle as a circuit and indicator. Galvani thought the leg supplied electricity, but Alessandro Volta thought otherwise, and he built the voltaic pile, an early type of battery, as proof. Continuous current from batteries smoothed the way for the discovery of G. S. Ohm’s law, relating current, voltage (electromotive force), and resistance, and of J. P. Joule’s law of electrical heating. Ohm’s law and the rules discovered later by G. R. Kirchhoff regarding the sum of the currents and the sum of the voltages in a circuit are the basic means of making circuit calculations.In 1819 Hans Christian Oersted discovered that a magnetic field surrounds a current-carrying wire. Within two years Andr頍arie Amp貥 had put several electromagnetic laws into mathematical form, D. F. Arago had invented the electromagnet, and Michael Faraday had devised a crude form of electric motor. Practical application of a motor had to wait 10 years, however, until Faraday (and earlier, independently, Joseph Henry) invented the electric generator with which to power the motor. A year after Faraday’s laboratory approximation of the generator, Hippolyte Pixii constructed a hand-driven model. From then on engineers took over from the scientists, and a slow development followed; the first power stations were built 50 years later.
In 1873 James Clerk Maxwell had started a different path of development in the Invention Of Electricity with equations that described the electromagnetic field, and he predicted the existence of electromagnetic waves traveling with the speed of light. Heinrich R. Hertz confirmed this prediction experimentally, and Marconi first made use of these waves in developing radio (1895). John Ambrose Fleming invented (1904) the diode rectifier vacuum tube as a detector for the Marconi radio. Three years later Lee De Forest made the diode into an amplifier by adding a third electrode, and electronics had begun. Theoretical understanding became more complete in 1897 with the discovery of the electron by J. J. Thomson. In 1910?11 Ernest R. Rutherford and his assistants learned the distribution of charge within the atom. Robert Millikan measured the charge on a single electron by 1913.