I have a project where I need a motor that can turn some number of rotations which will spool up a cable attached to a spring-closed device to open it up. When power is disconnected, the spring closure will cause the spool to unwind and the device to close.
In the closed position, no power is available. (i.e. The closure mechanism needs to be 100% passive.)
In order to keep this open for some time, I will need a motor that is capable of being stalled for long periods without having the windings burn up. I know some motors can do this, such as the motors they use on spring closed HVAC dampers, but I don't know how to find them or if there's a particular name I should be using to find them. I know I could probably do this with a stepper motor, but that seems overkill for the application.
The only requirements are higher torque to open this mechanism, no gearing that prevents the motor from spinning when power is disconnected, and the ability to be stalled.