To provide a cryopump and a refrigerator which can effectively control a cooling temperature at each cooling stage.
The refrigerator of the cryopump includes a first cylinder and a second cylinder, a first cooling stage, and a second cooling stage. The first cylinder and the second cylinder are connected to each other in series. The first cooling stage is cooled to the first cooling temperature, and the second cooling stage is cooled to the second cooling temperature by periodically suctioning operation gas into the interiors of the first cylinder and the second cylinder, by expanding it, and by exhausting it to the outside. A control part controls the air-intake/exhaust period of the operation gas to the refrigerator so that it can maintain the first cooling temperature at target temperatures. A radiation shield includes a shield substrate and a radiation-absorbing layer. The shield substrate has an outer surface which is opposite to the inner surface of a pump container, and the radiation-absorbing layer covers at least part of the outside surface of the shield substrate with a material having a higher emissivity than the shield substrate so that the air-intake/exhaust period can be shortened, and that the second cooling temperature can be made lower than a required cooling temperature.
| JPH1073077A | 1998-03-17 | |||
| JP2004003792A | 2004-01-08 | |||
| JPH0549826B2 | 1993-07-27 | |||
| JPH0868380A | 1996-03-12 |
Yusuke Murata
Tomoyuki Miki
Tomisho Teruo
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