Did anyone ever buy one to take it apart ? Just to see how it's working ? Reelf Terry schrieb: > > The shaker flashlight has just the mechanism. 1 minute of shaking gives 5 > minutes of LED illumination. The link is below. > > http://www.y2ksurvivalfood.com/starlight.html > > Cheers > Terry > > At 07:46 PM 4/13/00 -0400, you wrote: > >Are you looking for an off-the-shelf solution, a kluge, > >or a new kind of product? > > > >If I were designing this sort of thing from scratch I would > >first of all take note of your requirement that the device > >produce electricity even when the actual tool was at rest. > >That requirement means that whatever kind of generator I come > >up with has to run continuously. So you are talking here > >about a small efficient generator that consumes little > >air when idling, but probably a fair amount when activating > >other items such as solenoids. > > > >While the first thing that comes to mind is a rotary > >generator, this would probably NOT be a good choice > >here. Instead I would opt for a reciprocating style > >generator. Instead of having a rotor that rotates > >next to a set of magnetic poles, you would have an internal > >cylinder that carries the magnetic field. This could be > >simply a very small but strong cylindrical bar magnet. > >They make some amazing rare-earth magnets for things like > >hard drive head positioners. You could probably make > >one that had a cylinder say 1/4" in diameter and 1/2" > >long. This would be connected directly to a little > >piston assembly. When air under pressure is applied, the > >cylinder would first move in one direction, and then > >a set of two mechanical valves would be opened and closed > >in sequence uch that the inner cylinder constantly moved > >back and forth due to the change in which valve was letteing the air > >in, and which valve was letting the air out. > > > >Surrounding the reciprocating magnet would be a stationary > >coil with many turns of fine wire. As the magnet went back > >and forth the coil would develop an AC voltage. Low voltage > >diodes would full-wave rectify the voltage and on the > >board with the PIC would be some reasonable sized capacitors > >to reduce ripple. Because the output of the generator is > >true AC you could use straightforawrd voltage multiplier > >techniques (such as the marx multiplier) to raise the voltage > >to any desired level. > > > >A receprocating cylinder generator can run at fairly low > >speeds and still do a good job of producing electrical > >power. A simple small air regulator would ensure that > >voltage was fairly constant. Note that such a device would > >probably be better off running in "parallel" with the main > >tool, rather than in "series" with it, though both > >arrangements can be made to work. > > > >So where do you buy one of these things? I don't know. > >I don't even know if anyone manufactures a device like > >I described. If not, maybe someone should. > > > >Fr. Tom McGahee > > > >-----Original Message----- > >From: Morgan Olsson > >To: PICLIST@MITVMA.MIT.EDU > >Date: Thursday, April 13, 2000 5:53 PM > >Subject: Air powered electronics > > > > > >I4m working on a project where the customer don4t want electric connection. > >And no batteries needing to charge, switch or anything like that either. > >Too dark/small/dusty to use solar power. > > > >It4s a kind of moving hose connected pressure air driven tool, that I4m > going to > >automate and improve somewhat. > >Current verison do have air-logic, but a microcontroller based will have more > >facilities. > > > >So, I got plenty of air, standard pressure 7bar, filtered, dehumidized, oil > >free. > > > >My power requirement is about 12V, 1W. > > > >Lifetime also is an issue as this is industrial, and noise must not be too > high. > >Cost is always an issue... > >Maximum alowed airelectric generator size is 0,5 litre. > > > >I have sketched of a number of solutions, but nu really good. > >Unfortunately i have no rotating part on that tool, (just cylinders) and also > >the sensors need power when tool is at rest. > > > >Probably someone have been thinking about this before, and a good place to > ask > >is this list :) > > > >So...?? > > > >Thanks in advance. > > > >/Morgan > >Morgan Olsson morgans.rt@telia.com > >Morgans Reglerteknik, Hdllekes, 277 35 KIVIK, SWEDEN > > tel +46(0)414-446620, fax +46(0)414-672324 > > -- BAMBERG & MONSEES GbR Systeme fŸr Wissenschaft und Technik Steindamm 22 * D-28719 Bremen Fon +49-421-646775 * Fax +49-421-646785 http://www.ewetel.net/~bamberg.monsees/