| 摘要 |
PURPOSE:To reduce thrust, by forming a passage communicating a bearing chamber with an outlet of a braking fan in a body. CONSTITUTION:There is formed in a body 10 a passage 17 communicating a bearing chamber 14 for a main shaft 6 of a rotor 4 with an outlet of a braking fan 7 to thereby equalize pressure in the bearing chamber 14 to pressure at the outlet of the braking fan 7. Thus, suction pressure of the braking fan 7 may be reduced. Accordingly, even when the diameter of the rotor 4 is small, and there is almost no difference in diameter between the main shaft 6 and the rotor 4, thrust of the rotor 4 may be reduced. |
