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Doug Goncz
May12-04, 05:22 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Dialight has donated a white LED traffic signal module for my bicycle headlight\nexperiments. It is to be mounted with rubber windshield mounting strip into a\nhole in a bicycle fairing, which then is mounted to a bicycle. It has a great\nbeam pattern for illuminating a road. Trapezoidal.\n\nThe operating voltage is 80-135 VAC of unknown frequency. I believe I can\ngenerate this with a ceiling fan motor rated 225 rpm driven by the pedals of a\nbicycle which operate over a similarly scale range. The connection will by by\nbicycle chain from a 33-62 tooth chain ring to an eight tooth pinion on the\nmotor.\n\nAs the rotational speed increases, I expect the frequency and open circuit\noutput voltage will increase linearly. Can any of you confirm this? I think\nit\'s Faraday\'s law here in form B cross M = E.\n\nWhat one does is connect a car battery to the generator for a moment, just long\nenough to allow the current to rise on the impedance exponential to a value\nthat can magnetize the steel internal rotor. Then, although initiation is by\npermanent magnet action in the rotor, induction motor action prevails at speed,\ngenerating powerful currents in the rotor. An external capacitor is required to\nkeep it going, but no AC or DC field input is required.\n\nAs the AC motor is wound externally, I expect its resistance to be lower than\nthe DC generator I already have. More room for larger wires and all that. I\nwill report if I can get some figures, most likely a weighted bit of bicycle\nchain under the influence of gravity, generating large accelleration in the\nsystem and a measureable photographable trace on the oscilloscope with V and F\ntaken off with dividers. Or, since I can operated the pedals while parked, a\nfew rotations under leg power. You see, the bipod kick stand has a wooden brace\nbeneath it, without which the legs would spread and fail under my weight.\n\nAnyway, it\'s an intriguing opportunity, as the chain of DC generator to\ninverter to AC operated LED power supply to DC operated LED under current\nreguation has certain losses, and I don\'t exactly know where they are....\n\nThe motor, purchased from Surplus Center, has actually got a 17mm shaft and I\nam sending it out for machining to 5/8 inches. Surplus Center, which by now has\nprobably corrected the listing, offered compensation for my inconvenience. How\nnice of them. Arnie, I think it was, there. After turning to 5/8, I am to slot\nthe shaft for the pinion using a jig and techniques pictured at:\n\nhttp://users.aol.com/DGoncz/MotorGenerator\n\n\nYours,\n\nDoug Goncz ( ftp://users.aol.com/DGoncz/ )\n\nRead about my physics project at NVCC:\nhttp://groups.google.com/groups?q=dgoncz&scoring=d plus\n"bicycle", "fluorescent", "inverter", "flywheel", "ultracapacitor", etc.\nin the search box\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>Dialight has donated a white LED traffic signal module for my bicycle headlight
experiments. It is to be mounted with rubber windshield mounting strip into a
hole in a bicycle fairing, which then is mounted to a bicycle. It has a great
beam pattern for illuminating a road. Trapezoidal.

The operating voltage is 80-135 VAC of unknown frequency. I believe I can
generate this with a ceiling fan motor rated 225 rpm driven by the pedals of a
bicycle which operate over a similarly scale range. The connection will by by
bicycle chain from a 33-62 tooth chain ring to an eight tooth pinion on the
motor.

As the rotational speed increases, I expect the frequency and open circuit
output voltage will increase linearly. Can any of you confirm this? I think
it's Faraday's law here in form B cross M = E.

What one does is connect a car battery to the generator for a moment, just long
enough to allow the current to rise on the impedance exponential to a value
that can magnetize the steel internal rotor. Then, although initiation is by
permanent magnet action in the rotor, induction motor action prevails at speed,
generating powerful currents in the rotor. An external capacitor is required to
keep it going, but no AC or DC field input is required.

As the AC motor is wound externally, I expect its resistance to be lower than
the DC generator I already have. More room for larger wires and all that. I
will report if I can get some figures, most likely a weighted bit of bicycle
chain under the influence of gravity, generating large accelleration in the
system and a measureable photographable trace on the oscilloscope with V and F
taken off with dividers. Or, since I can operated the pedals while parked, a
few rotations under leg power. You see, the bipod kick stand has a wooden brace
beneath it, without which the legs would spread and fail under my weight.

Anyway, it's an intriguing opportunity, as the chain of DC generator to
inverter to AC operated LED power supply to DC operated LED under current
reguation has certain losses, and I don't exactly know where they are....

The motor, purchased from Surplus Center, has actually got a 17mm shaft and I
am sending it out for machining to 5/8 inches. Surplus Center, which by now has
probably corrected the listing, offered compensation for my inconvenience. How
nice of them. Arnie, I think it was, there. After turning to 5/8, I am to slot
the shaft for the pinion using a jig and techniques pictured at:

http://users.aol.com/DGoncz/MotorGenerator


Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ )

Read about my physics project at NVCC:
http://groups.google.com/groups?q=dgoncz&scoring=d plus
"bicycle", "fluorescent", "inverter", "flywheel", "ultracapacitor", etc.
in the search box

Doug Goncz
May16-04, 12:57 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>I\'ve registered for EET 350 towards my MET degree at ODU. There is a solid\nchapter in the text on AC and DC generators and motors. So by August 15th, I\nshould have more than enough theory to make this induction motor work as a\ngenerator.\n\nTeusday on the way to grief therapy I\'ll drop off the shaft for machining to\nfit the existing pinion cog, thereby making interface to the left side chain\nwheel, mounted on a tandem crankset. Jensen is just a short ride from the\ntransfer point, King Street Metro Station.\n\nThey\'ll have to turn, slot, and grind the shaft, because it\'s going to spring\nopen when the slot goes through to the hollow core, which is usually used to\nrun light wires in its OEM ceiling fan application.\n\nIt may be possible to establish a 60 Hz resonance with the motor windings and a\ncapacitor. I wonder what that will feel like on the road. I do not know if the\nrecommended capacitor, 350 microfarads, 250 WVDC, is anywhere near what\'s\nneeded for such a slow resonance and large inductor. And no LCR meter on hand,\njust an L adapter kit that I must build.\n\nOh, there\'s a scope, too. Why don\'t I hook up a measured cap in series and then\nin parallel, and sweep with the scope to look for a phase change? Yeah, that\'s\nthe ticket.\n\n&gt;The operating voltage is 80-135 VAC of unknown frequency.\n\nI\'m hoping that the specified 120 VAC nominal know to be 60 Hz US implies I can\nrun from 80 VAC 40 Hz to 135 VAC 67 Hz, which is what the generator should\nproduce. I\'ll ask Dialight.\n\n\nYours,\n\nDoug Goncz ( ftp://users.aol.com/DGoncz/ )\n\nRead about my physics project at NVCC:\nhttp://groups.google.com/groups?q=dgoncz&scoring=d plus\n"bicycle", "fluorescent", "inverter", "flywheel", "ultracapacitor", etc.\nin the search box\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form">&nbsp;&nbsp;View this Usenet post in original ASCII form </a></div><P></jabberwocky>I've registered for EET 350 towards my MET degree at ODU. There is a solid
chapter in the text on AC and DC generators and motors. So by August 15th, I
should have more than enough theory to make this induction motor work as a
generator.

Teusday on the way to grief therapy I'll drop off the shaft for machining to
fit the existing pinion cog, thereby making interface to the left side chain
wheel, mounted on a tandem crankset. Jensen is just a short ride from the
transfer point, King Street Metro Station.

They'll have to turn, slot, and grind the shaft, because it's going to spring
open when the slot goes through to the hollow core, which is usually used to
run light wires in its OEM ceiling fan application.

It may be possible to establish a 60 Hz resonance with the motor windings and a
capacitor. I wonder what that will feel like on the road. I do not know if the
recommended capacitor, 350 microfarads, 250 WVDC, is anywhere near what's
needed for such a slow resonance and large inductor. And no LCR meter on hand,
just an L adapter kit that I must build.

Oh, there's a scope, too. Why don't I hook up a measured cap in series and then
in parallel, and sweep with the scope to look for a phase change? Yeah, that's
the ticket.

>The operating voltage is 80-135 VAC of unknown frequency.

I'm hoping that the specified 120 VAC nominal know to be 60 Hz US implies I can
run from 80 VAC 40 Hz to 135 VAC 67 Hz, which is what the generator should
produce. I'll ask Dialight.


Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ )

Read about my physics project at NVCC:
http://groups.google.com/groups?q=dgoncz&scoring=d plus
"bicycle", "fluorescent", "inverter", "flywheel", "ultracapacitor", etc.
in the search box