Abstract: A turbine tool design with a number of innovative aspects which may be incorporated into the tool individually or as a group. One aspect relates to improved speed control, based on an elastically deformable governor member disposed within the rotating impeller assembly and having a substantially uniform cross-section. Another aspect relates to a overspeed safety configuration that employs secondary, or “retro”, nozzles that are enabled when the elastically deformable governor member is removed from the impeller assembly. Another aspect relates to routing the motive fluid exhaust through the operator-adjustable throttle assembly. Still another aspect relates to an approach to axially preloading the bearings supporting the rotating shaft of the impeller assembly.

Abstract: A turbine tool design with a number of innovative aspects which may be incorporated into the tool individually or as a group. One aspect relates to improved speed control, based on an elastically deformable governor member disposed within the rotating impeller assembly and having a substantially uniform cross-section. Another aspect relates to a overspeed safety configuration that employs secondary, or “retro”, nozzles that are enabled when the elastically deformable governor member is removed from the impeller assembly. Another aspect relates to routing the motive fluid exhaust through the operator-adjustable throttle assembly. Still another aspect relates to an approach to axially preloading the bearings supporting the rotating shaft of the impeller assembly.