Opening a window on self running motors

[mbrownn]

Im not sure I agree with you on the poor torque comment Mr Brown. Have you ever pulled apart a brushless motor, like the ones found in RC cars etc? I was quite surprised to find it near identical to the window motor, with just a steel case completely shrouding the motor. But no stator laminations or cogging when turned by hand (might be worth doing some tests to see if the steel shroud around the outside makes more torque?)

I think peoples perception of the window motor being low torque is because no one has built it properly yet. How many window motors do you see with more than one coil? Or phase? There aint many out there. Heck its hard enough to find a good replication that uses hall sensors. Next, do the math on the power flowing through most of these replications. In most cases its less than 24 watts. Heck, my 20 kilo rotor with a single 6 filar coil only drew 500ma @ 36v when up to speed. I would love to see a good replication with mosfet Hbridge and completely encompassed in copper windings.

Anyway, no disrespect, just my 2 cents

I was comparing the window motor like most of the ones on youtube with off the shelf motors, I think a window motor, properly built as you say, will have good torque. As you say, coreless motors used on radio controlled equipment have huge torque. Maybe one of these motors would be a good candidate for using on this circuit.

You are right, I needed to correct my statement and I am not offended at all

Even though there was only half an amp draw from your supply I would bet there was a lot more in your coils if you have the recovery circuit on it. If its only drawing half an amp with no recovery I would increase its power and add the recovery.

[mbrownn]

Ren,

I built one..this is a pic of it running on a

Input 230V, 1-5A

12 circuit SG, got another pic of it somewhere running on a hall based circuit...

We got to talk about this wave form this thing generates.


Regards

That is a nice build with the coils close to the rotor. It would be nice to know some performance figures.

I have never built a window motor (I will as soon as I can) so I cant really comment but I'm interested to know what you think about the wave form.

[ren]

Ren,

I built one..this is a pic of it running on a

Input 230V, 1-5A

12 circuit SG, got another pic of it somewhere running on a hall based circuit...

We got to talk about this wave form this thing generates.


Regards

Hell yeah Erf. I love that thing. Good to see you again. With the hall I assume its the 1/2 or full wave circuit or are you using the hall to switch the SG circuit? And what about the wave form in question? 1/2, full or SG or does it generate it on all three regardless? If its the wave form we were talking about in our emails then this is very interesting.

Also, have you considered flattening out your bundles at all? One of the chaps on BM2 has just built a neo monster and he is finding his coils are flexing, he mentioned JBs window motor vid and that he had to epoxy the coils to stop them from flexing so much. Id be very interested to see if a flat broad coil performed better than a tightly bundled coil.

I got a months long service leave coming up soon bro (3 weeks time) so if I cant find the time to catch you before I definately will be able to then.

Love your work champ. Ive still got this window monster on my benchtop, he's next on the rebuild list after I finish my SG/G-Flux variation.

Talk soon.

Shan