Tinman's coil shorting circuit

[Vortex1]

Hi Vortex1,

Thanks for the schematic, looks good to me.  This version connects the second winding in parallel with stator coil B   i.e. I would say the second coil quasi shorts stator coil B because I assume the second coil has less L inductance in practice than stator coil B (winding space for the second coil is limited).  Nevertheless the 'short' does not represent a really low impedence like a MOSFET's on channel would insure for instance but this may not be a drawback.
Of course, some protection means are to be provided for the gate-source electrodes of the MOSFET to limit any control voltage within +/- 20V (spec for most MOSFETs including the IRF540 Brad used),  though these means are not needed to include in the first cut schematic. 

Gyula

Agreed. The first component  I always solder in is a protection Zener gate to source.. I also keep some aluminum foil shorting the leads of the FET until I'm ready to fire up the circuit and after the protection Zener is installed.. I can't remember the last time I destroyed a FET. I left the protection Zener off for clarity, but it is always installed in my tests.

Note that the right hand side of the circuit can be flipped, putting the diode and switch at the top + of the capacitor and it will be electrically equivalent to the original. (for additional clarity and convention, but not necessary.) It does give a solid ground line across the circuit for probing with the scope.

With 3 coils we have many possible combinations of coil phasing. I usually name the stator leads that came from the brushes as "Stator Brush lead A" and "Stator Brush lead B" to convey this phasing  information to others, but did not put it on the drawings at this time since we have not been given any phasing info by Brad.

Regards, Vortex1 / ION

[penno64]

Hey guys,


Thanks for the input and ideas.

Please consider only the components from Brad's videos.

Will be getting a look at that type of veroboard to see which way the pcb tracks run if any.

I have spent hours with only the components shown in the videos, trying all combinations and connections, with no success.

[penno64]

Hey Brad,

Thanks for the bone, but it was  ............

Guys, the videos clearly show only two stator coils wired directly to the PCB with no other connections. I see no other coil ?

Also, in one of the videos, Brad says that the only mod to the motor was to ease off the spring
tension to the brush.

Is it possible to use the voltage from one coil to turn on OR off the mosfet used to short the other coil?

Penno

[poynt99]

penno,

There are hidden components under the pcb and in the motor.

It's unfortunate you've wasted so much time on this thinking all has been revealed.

[Magluvin]

From the little I know about this subject, something is strange.

What I find interesting is the fact that the motor runs at all with just input to the armature.

How is it that the armature induces the stators and have motor action???

Like when we have a rotor with mags and when we load the stator coils, the rotor should be dragged down, not keep going.

Mags