A-10 Electro-Pneumatic Switch Machines

A-10


A-10 Electro-Pneumatic Switch Machines

The A-10 Electro-Pneumatic switch machine is a rack and pinion type machine. It employs two identical single-acting air cylinders with identical piston assemblies, a vertical crank shaft, a circuit controller and a point detector mechanism. The switch assembly is encased in a rugged case iron housing with mounting flanges for direct mounting to the track ties. The A-10 incorporates a radial arm point detector mechanism. Movement of the detector arm causes a shift in the circuit controller contacts. This prevents making indication contacts unless both the machine and the switch point are in their full respective normal or reverse position. The detector mechanism is designed to escape wear from frequent operation of the switch and from external vibrations. Effects of switch stroke variation are compensated by adjustment of external mechanical parts. All A-10 machines are provided with a hand crank for manual operation. For safety, the crank cannot be meshed with the crank’s gear until the valve yoke has been removed, which cuts off the machine’s air supply. Conversely, to return to power operation, the hand crank must be removed.