Pneumatic starters

Abstract

Pneumatic starters including a housing formed in sections interfit in telescopic and abutted relation, a cap forming its upstream end, a nozzle unit at the open end of said cap defining therewith a shallow chamber constructed to receive a flow of fluid under pressure to power said rotor and provide for its content a substantial pressure head, said end cap and nozzle unit being coaxially extended by a turbine assembly section, the rotor of which positions outwardly of the end thereof immediately adjacent said nozzle unit, positioning its buckets in coaxially aligned relation to its nozzles, said rotor nesting in a relatively axially extended portion of a cylindrical wall structure which forms a shroud for said nozzle unit, lines the inner wall of said housing and peripherally shrouds the buckets of said rotor, said nozzle unit being separable and interchangeable, said inlet chamber and required interrelation of the nozzles of said nozzle unit and the buckets of said rotor being achieved in assembly of said housing sections, a following downstream section of said housing mounting a trip valve assembly in its all structure and containing a drive transmission including a drive shaft coaxially coupled with and driven by the rotor drive shaft and having means connected therewith for normally maintaining said trip valve in inactive condition, and an associated fluid signalling and delivery system providing fluid to energize said starter and insuring automatic shut down thereof substantially simultaneously with the speed of rotation of said rotor exceeding a preset limit.