Spring caging mechanism for a coil spring rail brake

A spring caging mechanism for a rail brake, wherein the rail brake includes a rail brake enclosure housing at least one spring acting downwardly against a brake shoe mounted underneath the rail brake enclosure so as to urge the brake shoe against a rail when the rail brake is positioned over the rail, the spring caging mechanism comprising:

• a caging frame depending downwardly from the rail brake enclosure so as to bracket the brake shoe which is mounted under the enclosure and linked to the at least one spring in the enclosure, wherein said caging frame includes a pair of substantially parallel walls defining a brake shoe channel therebetween, wherein said channel is sized so that the brake shoe is suspended and snug in said channel for vertical translation of the brake shoe in said channel between raised and lowered positions corresponding to a spring caging position and a rail engaging position respectively,
• wherein opposed facing inner walls of said parallel walls include a corresponding pair of opposed facing first grooves,
• and wherein an oppositely disposed pair of second grooves are formed in oppositely disposed outer surfaces of the brake shoe and positioned so that, when the brake shoe is in said raised position said first and second grooves are adjacent and aligned so as to form, collectively, a pair of key-receiving bores on opposite sides of the brake shoe when in its raised position,
• a pair of elongate keys sized for snug sliding fitment into and along said pair of key-receiving bores, wherein when said keys are journalled in said bores the brake shoe is releasably locked in its raised position thereby caging the at least one spring in the rail brake enclosure.