| 摘要 |
PROBLEM TO BE SOLVED: To provide a vacuum pump which reduces an amount of an oil suctioned to a negative pressure chamber when the operation is stopped and enables lubrication to be quickly started when the vacuum pump is driven.SOLUTION: A vacuum pump 10 includes a rotor 23 and a housing 24 and generates a negative pressure in a negative pressure chamber 48, which is defined by a rotor 23 and a housing 24, as the rotor 23 rotates. The vacuum pump 10 includes: an introduction oil passage 64 which is connected to an oil pump and introduces oil into the vacuum pump 10; an atmosphere communication passage 56 which opens to the atmosphere and introduces air into the vacuum pump 10; and a valve body 58 and a spring 59 serving as a communication control mechanism which allows the negative pressure chamber 48 and the introduction oil passage 64 to communicate with each other and closes the atmosphere communication passage 56 when the vacuum pump 10 is driven and allows the negative pressure chamber 48 and the atmosphere communication passage 56 to communicate with each other and closes the introduction oil passage 64 when the vacuum pump 10 is stopped.SELECTED DRAWING: Figure 4 |
