Hey, I just do the grand concepts.
-- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators
And, it goes hand-in-hand, we have it a hell of a lot easier to bypass things. Switching at high power gets physically messy up around the
10s-100s of MHz due to stray inductance, parasitic capacitance and the finite speed of light. A switcher at 1MHz can be bypassed easily, by which I mean, it can be effectively modeled and treated with a lumped-constant paradigm, where you have loop inductance, bypass capacitance and that's it.Even with the best of materials (cough, beryllium), the best mechanical switching transmission you could come up with is going to be hard pressed to go over a few hundred Hz. Beyond that, things spring and warp way too much during a cycle to use in a non-resonant fashion. Most of the time, even moderate bypassing is completely out of the question: the equivalent of a
100uF ceramic chip capacitor is approximately a cubic foot of lead!We have it too easy. We rarely even have to balance things. MEs have to statically, AND dynamically, balance high speed rotating machinery. That sucks. Yes we occasionally do it, too, but only as a last resort (those last few ppm of THD or something) -- MEs have to do it on the "so it doesn't shake itself to pieces" level.
Tim
-- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms
1.6 million hits.
generally you can select the the units
why would they use such an awkward term? it seems to be a legal term.
Hybrid automobiles became popular?
-- ?? 100% natural --- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net
not
any
A dog clutch with a spring to disengage when there's no torque?
-- ?? 100% natural --- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net
Close, but maybe not close enough. The motors used with submersible bore pumps are 'thin' cylinders. They're usually supplied coupled to the pump but they do detach, I've done that to test them. Range of ratings right across your requirements.
Salespeople use horsepower because the number is bigger and torque because it means absolutely nothing.
-- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico@nctdevpuntnl (punt=.) --------------------------------------------------------------
AFAIR, most clutches are unidirectional, so that would be more like an SCR.
not
any
Four quadrant all-mechanical triggering, don't forget. And a gigantic range of operating torques.
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
I've never seen a clutch that latches.
Most of the watts hits are from electric bicycles. Removing the electric bikes from the count:
4,040,000 hits2,400,000 hits
Realistically, I would also need to test the words, bike, kilowatt, HP, kw, etc, but the above is a good start.
Treadmill manuals:
I skimmed a few and found that you can select US or metric units (miles or km), but the output power dispaly (if present) seems to be fixed in either KW or HP. Most of the cheapo units do not display power output, but prefer to display energy in the form of "calories burned". I'm not really familiar with these machines and may have hit upon the exceptions rather than the rule.
"Fractional Horsepower" is a very common term referring to motors smaller than 1HP.
Popular in the press. When mentioned in advertising and spec sheets, hybrid power is usually in the form of KW, not HP. As for sales:
It's not like there's a mad dash to buy hybrids but 25,000 new hybrids each month seems to qualify as popular.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Vassilevsky"
with
possibly
BLDC,
power
at
do
Well they're maybe not stored on a shelf, but if an ESP motor fails you'll get a replacement the next day no matter how isolated your well is.
OT - Tesla originally invented the submersible motor to use in trench warfare. It was used to drill a holes under the opposing forces trenches through which explosives could be placed and remotely detonated.
Peace loving guy, that Tesla ;-)
Something to do with his Balkan ancestry?
--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)
From what I've read, he was a good sales man.
So, its money not ancestry.
hamilton
That's ambiguous. There are at least two sorts of calorie - gram and kilogram.
--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)
Give me low speed torque every time. The difference between a small-block Chevy, and a Fiat 500 :-)
--
"For a successful technology, reality must take precedence
over public relations, for nature cannot be fooled."
(Richard Feynman)
The only kind that matters to gym patrons is the kilocalorie type.
Here's a typical machine display:
Distance Speed (mph/ km/h) Total Calories Burned Calories per Hour Level Time Heart Rate Target Heart Rate METs ** Watts
**No horsepower, no kilowatt-hours, no joules.
it's not a friction clutch.
manual gearboxes are full of them
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How did you do it?
-- Reply in group, but if emailing add one more zero, and remove the last word.
I guess one way would be two ratchet and pawls driving a single output shaft from counter-rotating input shafts.
More quietly, maybe drive a gear on a shaft that swings (via some wasted torque) to engage either a CW or CCW otuput gear (low output torque).
Best regards, Spehro Pefhany
-- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
If you can use a lower voltage with higher current, if there's a low duty cycle, and if there's some small initial rotation, a Marinov ball-bearing motor will produce tremendous torque. And heat.
Well, you never know.
Cheers
-- Syd
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