| 摘要 |
The present invention is directed to a sealing device for a rotary fluid machine having bearings which are disposed at opposite end portions in a shaft chamber and support a shaft, the sealing device being characterized by comprising a fluid seal of a fluid having a higher pressure than in the shaft chamber, the fluid seal being provided at a portion in the shaft chamber through which the shaft extends; usual dynamic pressure type bearings disposed in the middle of the fluid sealing device itself or in the vicinity of the middle thereof, the bearings being further received in a housing of the sealing device; and sealing members for partially confining a space defined between the housing and the bearings in an axial direction and a peripheral direction in order to form a closed loop; whereby the bearings are pressed downward by a differential pressure between a pressure of the fed fluid and a pressure in the outside of the shaft chamber so as to permit increasing the number of kinetic fulcrums for the shaft and to thereby heighten a safe speed of the shaft. According to the above constitution of the present invention, the fluid fed into the sealing device can be utilized effectively, and it can be realized to provide the highly efficient and inexpensive high-speed rotary fluid machine. |
