Torsional spring for a slam-shut safety device

摘要

A cam assembly for use in a slam- shut safety valve includes a cam having an elongated first cam arm, and the cam is pivotable about a rotational axis. The cam assembly also includes a torsional spring having a pair of stationary outer arms and a pair of pivotable inner arms, wherein the pair of stationary inner arms is coupled to a portion of the first cam arm. The pair of inner arms is adapted to act on the first cam arm to bias the cam into a position that allows the cam to be relatched in a valve rearming process. The pair of inner arms is symmetrically disposed about the first cam arm to prevent lateral displacement of the cam.