A pneumatic motor for pneumatic tools includes a cylinder provided therein with a vane wheel. A rotating shaft inserted in the vane wheel is provided with a withstanding member and a tightening member, which can push the withstanding member to move toward the vane wheel and tighten the vane wheel with the rotating shaft for avoiding gap between the vane wheel and the rotating shaft. Thus, when outside driving air pushes the vane wheel to rotate, the vane wheel can synchronously drive the rotating shaft to rotate immediately and truly. By so designing, this invention can solve the problems of the conventional pneumatic motor that is likely to cause starting delay, untrue in power transmission and easy to wear.

An air turbine drive spindle includes a rotary shaft, a bearing portion, a damper ring, a cover member, and at least one or more O rings. The bearing portion surrounds at least a portion of an outer circumferential surface of the rotary shaft. The damper ring is disposed at the outer circumferential side relative to the bearing portion with a gap being interposed therebetween. The cover member is disposed at the outer circumference side relative to the damper ring with a gap being interposed therebetween, and is configured to store the rotary shaft, the bearing portion, and the damper ring. At least one or more O rings are disposed in each of the gap and the gap.

A turbine power unit for a power tool having a turbine housing with an interior space configured to receive therein a fluid powered turbine supported for rotation on a bearing within the turbine housing. A service opening through the turbine housing into the interior space thereof, the service opening configured to permit installation and removal of a bearing into and out of the interior space of the turbine housing. A removable cover releasably securable to the turbine housing over the service opening and transitionable between an open configuration in which a bearing can be installed into and removed from the interior space of the turbine housing through the service opening and a closed configuration in which an installed bearing within the interior space is secured for operation in the turbine housing.

A turbine power unit for a power tool having a turbine housing with an interior space configured to receive therein a fluid powered turbine supported for rotation on a bearing within the turbine housing. A service opening through the turbine housing into the interior space thereof, the service opening configured to permit installation and removal of a bearing into and out of the interior space of the turbine housing. A removable cover releasably securable to the turbine housing over the service opening and transitionable between an open configuration in which a bearing can be installed into and removed from the interior space of the turbine housing through the service opening and a closed configuration in which an installed bearing within the interior space is secured for operation in the turbine housing.

A multi-stage turboexpander and a method for generating mechanical power therewith are disclosed. The multi-stage turboexpander includes a casing and a shaft, arranged for rotation in the casing. The shaft is supported by a first bearing at a first shaft end portion and a second bearing at a second shaft end portion. A first radial impeller and a second radial impeller are arranged between the first bearing and the second bearing on the shaft for co-rotation therewith around a rotation axis.

A multi-stage turboexpander and a method for generating mechanical power therewith are disclosed. The multi-stage turboexpander includes a casing and a shaft, arranged for rotation in the casing. The shaft is supported by a first bearing at a first shaft end portion and a second bearing at a second shaft end portion. A first radial impeller and a second radial impeller are arranged between the first bearing and the second bearing on the shaft for co-rotation therewith around a rotation axis.

An air turbine drive spindle capable of suppressing a pressure increase inside a through hole is provided. A spindle includes a rotary shaft and an outer circumferential member (a housing assembly, a cover and a nozzle plate). The rotary shaft is provided with a through hole. The outer circumferential member includes a bearing sleeve configured to surround at least a portion of an outer circumferential surface of the rotary shaft. The outer circumferential member includes a gas supply portion and a gas exhaust hole. The spindle includes a second gas exhaust portion (a first gas exhaust hole and a first gas flow passage). The second gas exhaust portion is independent of the gas exhaust hole and continuous to outside from a gas exhaust space.

An air turbine drive spindle capable of suppressing a pressure increase inside a through hole is provided. A spindle includes a rotary shaft and an outer circumferential member (a housing assembly, a cover and a nozzle plate). The rotary shaft is provided with a through hole. The outer circumferential member includes a bearing sleeve configured to surround at least a portion of an outer circumferential surface of the rotary shaft. The outer circumferential member includes a gas supply portion and a gas exhaust hole. The spindle includes a second gas exhaust portion (a first gas exhaust hole and a first gas flow passage). The second gas exhaust portion is independent of the gas exhaust hole and continuous to outside from a gas exhaust space.

An air turbine drive spindle includes a rotary shaft, a bearing portion, a damper ring, a cover member, and at least one or more O rings. The bearing portion surrounds at least a portion of an outer circumferential surface of the rotary shaft. The damper ring is disposed at the outer circumferential side relative to the bearing portion with a gap being interposed therebetween. The cover member is disposed at the outer circumference side relative to the damper ring with a gap being interposed therebetween, and is configured to store the rotary shaft, the bearing portion, and the damper ring. At least one or more O rings are disposed in each of the gap and the gap.

A high torque dual speed turbine rotor for a lightweight hand held tool for grinding and polishing or for use with a spindle mounted pneumatic machine. The high torque dual speed turbine rotor includes a two-piece shaft with flow control screw disposed within the shaft. The shaft includes a first set of hollow openings, at a first position from one end of the shaft, in fluid communications with a first annular chamber of a rotor. There is also a second set of hollow opening, at a second position from the one end of the shaft, in fluid communications with a second annular chamber of the rotor. The flow control screw moves inside a threaded axial bore of the shaft from an open position inside the axial bore to the closed position corresponding to the second set of hollow openings.