The first electric-powered road vehicle is believed to have been built in Scotland about 1839 by Robert Anderson, but it, along with others within the next several years, were generally unsuccessful. The steamer had to wait for a boiler to build up pressure and was very noisy besides. The concept of an electrical engine that could start immediately and run quietly was very attractive at that time. There were disadvantages, however. Electric batteries were heavy, bulky, unreliable, and needed recharging after a short run. In 1880, there was a general improvement in the development of longer-lasting batteries. There still existed, however, excessive weight and bulk of the batteries and a need for frequent rechargings, although electric cabs appeared on the streets of London in the late 1800s. Steamers and electric vehicles gained only restricted acceptance on the continent as well. In France, the electric had a shining, brief hour of public acclaim when Camille Jenatzy, driving a Jeantaud electric, pushed the cigar-shaped vehicle to a record of sixty miles per hour on April 29, 1899. The high-speed run, however, burned out the specially fabricated batteries and the interest in electrics died almost as soon as the cheers of the attending public. It was in America that steamers and electric cars gained their most sustained measure of success. Eventually twenty different U.S. car companies would produce electrics; and in the peak of popularity, 1912, nearly 35,000 were operating on American roads. But even America could not shake the limitations of the bulky batteries and the short ranges between recharging. Steamers were actually more popular. More than 100 American plants were making steamers, the most famous of which were the Stanley brothers factory in Newton, Massachusetts. The "Stanley Steamer" had the affectionate nickname, "The Flying Teapot," and with good reason. In 1906, a Stanley Steamer was clocked at 127.6 miles per hour on the sands of Ormond Beach, Florida. In spite of this, the steamers, along with the electrics, were only living on borrowed time. Experiments were being made on an automobile powered by a gasoline-fueled, internal-combustion engine, and the steamers and electrics would not survive the impact of the coming collision. Internal-combustion automobiles did not just burst forth on the scene all of a sudden to crowd the electrics and steamers off the road. The theories of internal-combustion engines had been on the way ever since 1860, when Etienne Lenoir applied to the authorities in Paris for a patent on his invention, an internal-combustion engine powered by coal gas. Two years later, Lenoir hooked his engine to a carriage, and, although it was crude, it worked. It worked so poorly and so slowly (about one mile an hour), however, that he became discouraged and abandoned his efforts. In 1864, a resourceful Austrian in Vienna, Siegfried Marcus, built a one-cylinder engine that incorporated a crude carburetor and a magneto arrangement to create successive small explosions that applied alternating pressure against the piston within the cylinder. Bolting his engine to a cart, Siegfried geared the piston to the rear wheels, and while a strong assistant lifted the rear of the cart off the ground, Siegfried started the engine. The wheels began to turn and continued to turn with each successive "pop." Marcus signaled the assistant to lower the cart and watched it burp along for about 500 feet before it ran out of fuel. Ten years later, he built the new, improved version of his motorcar, and then, mysteriously washed his hands of the entire thing, saying it was a waste of time. (The second model, which is preserved in an Austrian museum, was refurbished and taken for a test run in Vienna in 1950. It reached a top speed of ten miles per hour on level ground.) Although Lenoir and Marcus did not have the grit and determination to pursue their enterprises, they made some valuable contributions to the theory of internal-combustion engines. It would be overstating the case to credit them with the creation of the internal-combustion automobile, however.
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The valve seal is a unit that goes over the end of the valve stem. It keeps excess oil from getting between the valve guide and the valve stem.
Semiconductors are made from material somewhere between the ranges of conductors and nonconductors. Semiconductors, basically, are designed to do one of three things: (1) stop the flow of electrons, (2) start the flow of electrons, or (3) control the amount of electron flow. A semiconductor diode is a two-element solid state electronic device. It contains what is termed a "P" type material connected to a piece of "N" material. The union of the "P" and "N" materials forms a PN junction with two connections. The "anode" is connected to the P material; the "cathode" is connected to the N material. A diode is, in effect, a one-way valve. It will conduct current in one direction and remain non conductive in the reverse direction. When current flows through the diode, it is said to be "forward biased." When current flow is blocked by the diode, it is "reverse biased." When a diode is reverse biased, there is an extremely small current flow; actually, the current flow is said to be "negligible." When the P and N are fused together to form a diode, it can be placed in a circuit. The P material is connected to the positive side of the battery and the N material is connected to the negative side of the battery. Connected in this manner, current will flow. If connected in the reverse manner, current will not flow.
A "worm gear" is a shaft with very coarse thread, which is designed to operate or drive another gear or a portion of a gear. The special shape of the gear allows the rotation direction to be turned when the gears engage with minimal friction. An example is found inside the steering box, where the steering shaft turns a worm gear that is screwed into a large nut. The nut moves back and forth on friction-reducing ball bearings, which are continuously recirculated by dropping into the nut's bored channels and emerging at the opposite side. Power to move the nut comes from pressurized fluid entering from a pump through rotary valves that open in response to the steering wheel. The worm gear engages the cross shaft through a roller or by a tapered pin.
The manual worm and tapered peg steering gear has a three-turn worm gear at the lower end of the steering shaft supported by ball bearing assemblies. The pitman shaft has a lever end with a tapered peg that rides in the worm grooves. When the movement of the steering wheel revolves the worm gear, it causes the tapered peg to follow the worm gear grooves. Movement of the peg moves the lever on the pitman shaft which in turn moves the pitman arm and the steering linkage.
Wires and cables are conductors of electricity. Usually, they are made of annealed copper and are used to carry electricity to the various electrical devices and equipment on passenger cars and trucks. Wires and cables must be the right size for the application and must have proper insulation. If the wire or cable is too small in cross section or too long for its size, its resistance will be too great and valuable voltage will be lost. This will then result in poor operation of the electrical device in the connecting circuit. Wire size and length determines the resistance of the wire. Wire and cable sizes are expressed by a gauge number, which indicates the cross-sectional area of the conductor. The cross-sectional area of the wires is given in metric size or circular mils. The diameter is given in decimals of an inch. A circular mil is a unit of area equal to the area of a circle one mil in diameter. A mil is a length unit equal to .001 inches. The larger the diameter of the wire or cable, the smaller the gauge size number. Cables are made of several strands of wire. The cross-sectional area is equal to the circular mil area of a single strand times the number of strands. Special gauges are available for measuring the gauge size of wires and cables. Many multi-purpose electrician's pliers feature wire size holes for stripping, cutting, and crimping operations. When comparing cables, consider that the external diameter of insulated wire or cable has nothing to do with its current-carrying capacity. Thick insulation will make a small gauge wire look much larger. It is important that only the size of the metal conductors are compared.
