what is the green component? what is the name?
I don't know the name for that specific device, but it is a type of ratchet mechanism.
Edit: To further classify this, one might call it a ratcheting freewheel mechanism. The one thing of which I'm unsure how to classify, is that the ratchet mechanism is based on the deflection of the ratchet, rather than a pivoting arm-and-spring style mechanism.
i found the photo on google. im looking for a plastic gear component that allow gear to turn freely in one direction, but engage in opposite direction. do u have any idea?
I'm sure someone makes plastic freewheels, or you could easily have it fabricated for you. As far as that specific design, I don't know.
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