Is their any sort of motor that can make multiple revolutions and then stop while being powered? I am looking for something similar to a headlight motor to open a valve on my Mig welder. I always figured a headlight motor was basically a stepper motor but I don't understand exactly how it works.

I do not want to use any sort of driver ic to do this. Ideally this motor can make 2 or 3 rotations either way (example, switch on - motors turns 3 times one way and switch off - motor turns 3 times backwards).

Thanks

 

Motors are pretty stupid. Any brainless motor that stops after 3 turns must have a limit switch or it's so weak that it can stay powered and not burn up after it hits a mechanical stop. I'm betting on a limit switch for this one because it takes a lot of force to open a gas valve.

 

it would be easier to use the right part for the job: a solenoid valve. That's what gas mig welders have already.
http://weldingdirect.com/gasvasokit17.html

I doubt you could even get a headlight motor for that price.

 

There are modern Automotive window motors that have an electronic circuit breaker, this does not use limit switches or fuses, when the window is operated and the window is raised or lowered, if the switch is not released the C.B. automatically cuts out for that direction.
A wreckers yard would be a source.
Max.

 

I do not want to use a solenoid to complete this task. I suppose I'll just stick to the schematic I drew up for another purpose.