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Carpal Tunnel
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Pooh-Bah
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Pooh-Bah
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To me, dynamo has always meant a generator, first and foremost. It's use to denote a person of extreme energy and drive I have aways regard as an analogy to the original meaning.
My prized possesion, as an eleven-year-old, was a bicycle whose lights were powered by a dynamo, rather than by batteries like thise of most of my contemporaries.
Most motor cars also had dynamos to re-charge their batteries, up until the '60s when they were replaced by the more efficient alternator.
I assume that the latest developments in clockwork radio sets use the mechanism to drive a dynamo which powers the receiver and speakers.
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old hand
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old hand
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(in ref to RC's post....) wot 'e said.
stales
(PS Dynamo is laundry powder in Oz - and presumably elsewhere)
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old hand
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old hand
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Good 'ol Chambers:
dynamo, the contraction for dynamo-electric machine, a machine for generating electric currents by means of the relative movement of conductors and magnets. [Gr. dynamis, power]
Learned about dynamos in Year 5 physics. I reckon you guys should get away from your PC and into the workshop more often.
stales
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Carpal Tunnel
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Carpal Tunnel
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Most motor cars also had dynamos to re-charge their batteries, up until the '60s when they were replaced by the more efficient alternator.
Us'ns, who refer to our motor cars as autos, or just cars, have always used the term generator for the dynamo.
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Carpal Tunnel
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Carpal Tunnel
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And marvelous to me is the phenomenon of wind-up radios that play for quite remarkable lengths of time when wound up like an old-fashioned clock. Wonderful for the third world people or long term boondockized USns.
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Carpal Tunnel
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Carpal Tunnel
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...have always used the term generator for the dynamo.I know this is *different technology, but there was a time when neither was the case. http://www.old-engine.com/maghma.htm
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Carpal Tunnel
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Carpal Tunnel
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Why not go back to a few fundamentals? When a wire is moved through a magnetic field, a current is generated in the wire. In physics the prof had a large permanent magnet shaped like a horseshoe. When he moved a plain wire between the two ends of the magnet, it made a big very sensitive meter needle move, and the faster he moved the wire, the further the needle moved proving he was making a weak electric current in the wire. If he made a bundle out of the wire and passed it between the North and South pole, the needle moved much more. So a generator is just a very long wire wound into an "armature". When this is made to spin very rapidly between two magnetic poles, you have a generator or dynamo. With different ways of winding the armature and placement of magnets, either direct current or alternating current can be produced. In the early days, Thomas Edison favored direct current, because it would drive a motor with more power, such as those used in elevators. But the direct current generated at Niagara Falls had its voltage drop so fast in the transmission lines that it could not be sent to New York City. Along came a Hungarian, Nikola Tesla, who showed that alternating current was more desirable because its voltage could be raised or lowered by transformers, and so it could be transmitted for great distances. So alternating current became the widely used system of today. When semi-conductors became available, it became possible to raise voltages of direct current, and now direct current can be transmitted long distances with very low losses, and then turned back into alternating current to use in the home. The early automobiles used direct current generators to charge the battery. But when motor was idling, current output was insufficient to keep battery charged. When semiconductors became available, alternators in cars could keep battery charged even when idling. So cars now all have alternators. Dynamo and generator mean essentially the same thing, a means of turning rotatory motion into electricity. Alternator just specifies that it produces alternating current.
There will be a quiz.
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Carpal Tunnel
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OP
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Carpal Tunnel
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In the early days, Thomas Edison favored direct current, because it would drive a motor with more power, such as those used in elevators. But the direct current generated at Niagara Falls had its voltage drop so fast in the transmission lines that it could not be sent to New York City. Along came a Hungarian, Nikola Tesla, who showed that alternating current was more desirable because its voltage could be raised or lowered by transformers, and so it could be transmitted for great distances. So alternating current became the widely used system of today.
An addition to this excellent explication.
In the earliest days there was serious debate whether electricity should best be provided by a large "central station" serving a wide area, or by multiple smaller generators each serving a smaller area. In the latter case a single large building, for example a department store, might have its private own generator to power its own lights (selling any excess capacity to its neighbors).
This latter was the dominant concept, for "central station" made little sense when even the largest generators produced only a very limited amount of power. And indded, shortly after the turn of the century generator-technology had reached its maximum: if piston and shaft were built any bigger, the machine would simply tear itself apart by the force of its own vibration.
At that point Insul of Chicago Edison (formerly of GE) acquired a large site ideal for a large generator (ample access for coal to fuel it). He demanded from GE a turbine-driven generator with 5,000 kwh capacity -- five times the largest prior turbine. They pushed the envelope to 5,000 -- and within a few years of experience using it, Insul's engineers had pushed it up to 9,000 kwh. This huge jump in capacity was decisive in favor of the central-station model.
This turbine was such a breakthrough that when it was finally retired decades later, it was placed on display at GE's site in Schnectady, NY.
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