|
|
Charles Davis wrote:
If an impeller were to be cast for this air-induction/super-charging application, and was tied-in to the e-shaft (key-way or similar) would it work to have a suitable magnet cast-in to the periphery of the impeller, so that two coils could be mounted, 180 degrees apart, to provide ‘magneto-type’ spark to one set of plugs – one coil per rotor at 180* for a 2-rotor, and 120* for a 3-rotor – this sounds, to me, so simple that I am surprised nobody has done it before – how good would it be to have a completely battery-independent ignition system for amateur-built aircraft ? … maybe I should shaddup, & return to lurking …
The system you describe has been working perfectly a lot longer than I've been alive. All I can say is, don't let your wife catch you pulling the flywheel off your lawn mower to power your airplane 8*) There is a magnet cast into the flywheel, and the coil is built around a C shaped stack of stamped steel. That flywheel could possibly handle the RPM of the eshaft (but I wouldn't dare bet anything important on it).
I think the only issue you'd have is modifying the advance. You could accept the "good 'nuff" compromise of a static 20* to 25* in exchange for the bone dry simplicity. Possibly driving just the trailing plugs as a dead generator backup. That, combined with a gravity feed system would make your engine electrically independent. Or you could try to design some sort of advance control. Maybe use a MegaSquirt and write some code to control a stepper motor that moves the pickup?
I'm currently trying to use the space between the engine and the gearbox mount plate to install a blower and a generator. I think that is enough multipurposing of a single piece of aluminum for now. However, at some point in the future I may need a new lawn mower. 8*)
|
|