Patent ID: 8113769

Claim:
An expansion turbine with a variable nozzle mechanism comprising: an adiabatic expansion device located in a vacuum container having a turbine impeller therein, the adiabatic expansion device rotates and drives the turbine impeller during adiabatic expansion of very low temperature gas, and varies a throat area of very low temperature gas introduced in the turbine impeller by driving a nozzle member disposed near the outside end of the adiabatic expansion device by a drive force from a driving member located outside the vacuum container; a plate member provided detachably in contact with the outside end of the body of the adiabatic expansion device and a pressing member which presses the driving member, the nozzle member and the plate member against the body of the adiabatic expansion device, wherein the driving member, the nozzle member, the plate member and the body of the adiabatic expansion device are sequentially disposed in the axial direction of the turbine impeller, the support side of the nozzle member is connected to and supported by the plate member, and the drive side of the nozzle member is connected to and supported by the driving member.