Pachinko Taishou 13 - stepper motor is weak

[rjlatherow]

Getting started on bringing my new Nishijin Pachinko Taishou (1989 model) back from the dead. The big issue is the shooter - it makes a terrible grinding noise, and does nothing. If I start the move the shooter linkage by hand, it moves it a bit, but isn't strong enough to move it on its own. I pulled it out, and the cam has almost no torque. I assume the motor is dead -

Is there a replacement anyone can recommend or sell?

Thanks!

-RJ

[Drunkenclam]

If you can remove the motor and take a front and back picture, that would be helpful

[rjlatherow]

My pleasure! I'm including shot of the cabinet just in case I misidentified it....

I'm also doing it without the gear box -I assume that is seperate. I can easily stop the cam with my finger, and when I take it apart I can lightly hold the little gear still. Definately the motor.

-rj


back.jpgfront.jpgmotorside.jpgmotorside2.jpgmotorTop.jpgmotortop2.jpg

[compirate]

It's a type of stepper, isn't it? Perhaps a bad controller?

[rjlatherow]

Yeah, I think so. Based on the hideous grinding noises coming out of the thing I suspect the motor is bad. Any ideas for replacements?

[compirate]

any way to disassemble it? perhaps bushings are worn

[rjlatherow]

I learned a few things today-

First off, it's actually not a stepper motor - it's a 'asyncronous' motor. Inside its a little strange - there are 2 halves pressed together, with a bushing in both ends. There is a magnetic cylinder about an inch tall and an inch across, with walls 1/8 off an inch think. There are 2 small depressions in the top of the magnet . Inside of THAT is a plastic cup that fits inside the magnet. This has the spindle the gear rides on, but the important bit is the 2 little bumps on the rim of the cup that mesh with the depressions on the magnet. The magnet is the part that spins, and the cup goes along for the ride. If there is too much resistance, the plastic bumps will slip out of the magnet depressions. It's kind of a failsafe, I suppose. My cup bumps were very, very worn out, so it was barely grabbing hold of the magnet, hence the sketchy operation.

I melted some plastic onto it with the soldering iron, and pushed it into the magnet while to plastic was nice and hot to 'mold' them together. It works great so far - now I'm on to the next project. If I ever have to open it up again, I will take pictures. Thank you all for your help!
-rj