| 摘要 |
PROBLEM TO BE SOLVED: To provide an oil-free screw compressor in which its manufacturing can be easily carried out and flexing of a screw rotor is restricted.SOLUTION: An oil-free screw compressor of this invention comprises a screw rotor 14 including a screw part 14a and a shaft part 14c; a bearing 26 supporting the shaft part; a first seal part 38a arranged between the screw part and the bearing and oppositely facing against the shaft part; a first shaft seal unit 30 including a first communicating part 30a for communicating the bearing side and an outer peripheral surface in respect to a space between the shaft part and the first seal part; a second seal part 32a arranged between the first shaft seal unit and the bearing and oppositely facing against the shaft part; and a second shaft seal unit 32 including a second communicating part 32c for communicating the screw part with an outer peripheral surface in respect to a space between the shaft part and the second seal part. A casing 12 has an atmosphere communicating part connected to both the first and second communicating parts at an inner peripheral surface 12k of a shaft storing space 12j, and communicating the first and second communicating parts to the atmosphere.SELECTED DRAWING: Figure 3 |
