Turbomachinery

Abstract

In a turbomachinery (S 1 ) that is provided with an impeller ( 1 a ) and a shaft ( 2 ) that are to be fastened, the impeller ( 1 a ) and the shaft ( 2 ) are fastened by a two-way screw ( 3 ) of which the turning direction of the screw thread that is formed on the impeller ( 1 a ) side and the turning direction of the screw thread that is formed on the shaft ( 2 ) side are opposite directions. As a result, it is possible to fasten the impeller ( 1 a ) to the shaft ( 2 ) without the need for a complicated and large equipment, and the amount of work during fastening is reduced.

1 . A turbomachinery comprising an impeller that is rotatively driven and a shaft that transmits rotational power to the impeller,
 wherein the turbomachinery comprises a two-way screw of which a first end side serves as an impeller screwing region that is screwed together with the impeller and a second end side serves as a shaft screwing region that is screwed together with the shaft, with the turning direction of the screw thread that is formed at the impeller screwing region and the turning direction of the screw thread that is formed at the shaft screwing region made to be opposite directions, and   the impeller and the shaft are fastened by the two-way screw.   
     
     
         2 . The turbomachinery according to  claim 1 , wherein the two-way screw is formed with a material having a higher thermal conductivity than the impeller. 
     
     
         3 . The turbomachinery according to  claim 2 , wherein the two-way screw is formed with a steel material in the case of the impeller being formed with a titanium alloy. 
     
     
         4 . The turbomachinery according to  claim 1 , comprising a rotation inhibiting member that inhibits rotational movement of the impeller with respect to the shaft. 
     
     
         5 . The turbomachinery according to  claim 4 , wherein the rotation inhibiting member, with the rotation axis direction of the impeller serving as the lengthwise direction, is a fitting hole that is provided at a position offset from the rotation axis of the impeller and a pin member that is fitted in a fitting hole that is provided at a position offset from the rotation axis of the shaft. 
     
     
         6 . The turbomachinery according to  claim 5 , wherein the pin member is provided in a plurality at equally spaced intervals centered on the rotation axis of the impeller. 
     
     
         7 . The turbomachinery according to  claim 4 , wherein the rotation inhibiting member comprises:
 a fitting projection whose outer shape seen from the rotation axis direction of the impeller deviates from the rotation body shape, and is provided projecting in the rotation axis direction with respect to the impeller or the shaft, and   a fitting hole that is provided in the impeller or the shaft where the fitting projection is not provided, and in which the fitting projection is fitted.   
     
     
         8 . The turbomachinery according to  claim 7 , wherein the fitting projection has a shape whose center of gravity is on the rotation axis. 
     
     
         9 . The turbomachinery according to  claim 1 , comprising a lock bolt that abuts the two-way screw from the rotation axis direction of the impeller. 
     
     
         10 . The turbomachinery according to  claim 1 , wherein the turning direction of the screw thread that is formed on the impeller screwing region is set to a direction in which the fastening power between the two-way screw and the impeller increases due to a reactive force when the impeller is rotatively driven. 
     
     
         11 . The turbomachinery according to  claim 1 , wherein a fitting hole or a fitting projection that is capable of fitting a tool that rotates the two-way screw is provided on the impeller-side end face of the two-way screw, and an exposure hole that exposes the fitting hole or the fitting projection is provided in the impeller. 
     
     
         12 . The turbomachinery according to  claim 10 , wherein a fitting hole or a fitting projection that is capable of fitting a tool that rotates the two-way screw is provided on the impeller-side end face of the two-way screw, and an exposure hole that exposes the fitting hole or the fitting projection is provided in the impeller. 
     
     
         13 . The turbomachinery according to  claim 11 , wherein the fitting hole or the fitting projection that is capable of fitting a tool that rotates the two-way screw has a shape whose center of gravity is on the rotation axis of the impeller. 
     
     
         14 . The turbomachinery according to  claim 12 , wherein the fitting hole or the fitting projection that is capable of fitting a tool that rotates the two-way screw has a shape whose center of gravity is on the rotation axis of the impeller.