| 摘要 |
PROBLEM TO BE SOLVED: To provide structure reducing generation of noise and advantageous for cost reduction. SOLUTION: A lubricant seal type rotary vane oil rotary vacuum pump has a pump stage 17 including a gas inlet, a gas outlet 51, a suction chamber 11, and a pump stage housing 10. To reduce the generation of noise, a groove 54 is formed to at least a part around an outflow port of a passage 50 to the gas outlet which is formed between the suction chamber 11 and the gas outlet. The lubricant flowing out of the suction chamber is received in the groove to prevent the lubricant from flowing down to the inside of the suction chamber. COPYRIGHT: (C)2008,JPO&INPIT |
