Patent ID: 8887514
Filing Date: 2014-11-18
Classification: F04B

Abstract:
1. A cryopump control apparatus controlling an evacuation process of a cryopump that comprises a cryopanel which cools and thus condenses or adsorbs gas, and a pump housing which contains the cryopanel, comprising: a pressure control unit operative to stop pumping when detecting that a pressure in the pump housing decreases to a reference pressure; a time managing unit operative to determine first measurement time and second measurement time that is later than the first measurement time; and a vacuum retention evaluation unit operative to determine whether a difference between pressure values in the pump housing measured at the first measurement time and at the second measurement time is within an allowable range of pressure change, wherein the first measurement time is determined by adding correction time relating to an operating delay of pumping to a time point when the pressure in the pump housing is detected to be decreased to the reference pressure.