Wiktionary
return spring
n. (context mechanics English) The spring that returns a door handle or knob to its original position when rotated.
Usage examples of "return spring".
The firm' pin, bolt, and return spring for that Browning are in a box under my bed at Guard House.
Loomis twisted the left handgrip and let a return spring slide it to the dash panel, then pulled the right grip out to its stop.