Pulse motor build off time.

[MarkE]

If for purposes of simplicity we assume that your coils have no resistance, and are linear, then each coil dumps an energy:  E_IND = 0.5*L*I² into your capacitors.  The resistance of the circuit plus the switch must dissipate that energy as heat each cycle.  Total up the coils, multiply that by frequency at which each coil cycles and multiply by the current squared divided by two and you have the average powe tht will be dissipated.

[ramset]

here we have another entry ready for prime time


https://www.youtube.com/watch?v=tgX5cz1SMiw


enjoy


@Toad
keep a flipper to the ground [sending a PM]
[not sure if toads have ears....  ]


thx
Chet

[TinselKoala]

That one should be called the "OnanMotor".   

Meanwhile, the MescalMotor, which started as a project to reverse engineer the electronic Levitron, is coming along nicely. It's just a little toy compared to those ones up above, but it contains a few basic concepts that might be useful to other builders. Self-timed by shadows falling on CdS photoresistors configured as a "light operated potentiometer" which is fed to one of the inputs of a 741 bipolar-supply op-amp (the other input gets a feedback from the driver stage to smooth out the shape of the output response ramp). The Output of the op-amp then drives the bases of the PNP and NPN transistors in the push-pull output stage, which then drives the electromagnet coil, reversing its polarity according to which photoresisitor is shadowed by the ends of the sliding rod. The rod has magnets simply stuck to the ends in a NS===[coil]===SN configuration so that the coil attracts one side and repels the other side, and swaps when the coil polarity is flipped by the push-pull output stage. Push-pull, get it? The magnets have little grommets glued to the outer ends and a 5mm plastic air-soft BB inserted into the grommet hole, to make a nice striker for the piezoelectric elements which are mounted so that they bend a little bit when struck. It took me a few hours of trial and error to get the right mounting strategy for these elements that gave the highest voltages when struck by the oscillating rod. The outputs of the piezos are "alternate-parallel" into the fullwave bridge of 1n5817 Schottky diodes, and a 470 uF capacitor on the DC side of the bridge. From a cold start, it takes about 30 seconds to pump up the capacitor to where it will light up the green LED, which starts glowing at about 2.05 V or so. The piezo generators supply enough current now, though, to allow the voltage to climb as high as 2.22-2.24 V, which indicates that the LED is getting plenty current to glow fully bright. With no load on the FWB, the capacitor voltage will  climb to just under 9V... all on the output of the two small piezo buzzer discs alone.

http://www.youtube.com/watch?v=HTDitrH3glI

It's not nearly as elaborate as Tommey's motor, nor as powerful as the electromagnetic generator in the video above... but I didn't spend one cent of "new money" on it, it is entirely built with scavenged parts or parts and supplies purchased a long time ago for other projects. The Piezo discs, for example, have been kicking around in my junk box for around 12 years, I bought them at Halted Sales in California for about 5 cents each, still have 20 or so to use up somehow. Transistors salvaged from an MRI control board, wires from old CRT monitor cables, magnets bought a long time ago for magnet motor projects, CdS photoresistors donated by Fried Mike, op-amp from CRT monitor,  etc etc. All stuck together with Gel Superglue from the Dollar Store, two tubes for a dollar, can't live without that stuff any more, it works fast and sticks just about anything to anything else, works very well with the wood I use for frames, which is lauan mahogany plywood floor underlayment 5mm, also very cheap.

[hoptoad]

here we have another entry ready for prime time
https://www.youtube.com/watch?v=tgX5cz1SMiw
enjoy
@Toad
keep a flipper to the ground [sending a PM]
[not sure if toads have ears....  ]
thx
Chet

And now for something completely different ...... great video. That is certainly a different design approach. I love the imaginative yet simple designs that go into some motors. Does that central piston (magnet ?) follow a spiral path as it goes up and down the shaft ? I've got a pretty poor resolution screen and its hard to see some things very well.


Cheers.

[ramset]

There is an additional Prize offer in the wind ....
we shall see if it gets the OK .


has to do with Looping....?


good stuff indeed.


thx
Chet