Safety mechanism for materials handling system

摘要

A safety lock comprises a locking member (26, 28) which engages a support. An inner lock shaft (30a) actuates the locking member, the inner lock shaft having a first coupling face (35a) at one end thereof. An outer lock shaft (30b) has a second coupling face (35b) which engages the first coupling face when the inner lock shaft and the outer lock shaft are in respective engagement positions relative to each other. A coupling structure (18) moves to prevent engagement of said first coupling face with said second coupling face.