PURPOSE: To prevent dew from condensing on the outer wall surface of a device by discharging gas fed from an auxiliary cooling gas supply port to a low temperature gas generation section, through a pressure sensitive exhaust valve on the bottom of a valve box open upward via an exhaust port.
CONSTITUTION: An auxiliary cooling device 5 includes an auxiliary cooling gas supply port 51 and exhaust port 52 on the side wall of a low temperature gas generation section 3. The supply port 51 is fitted with a gas jet nozzle 53. This nozzle 53 is provided with a liquefied carbon dioxide cylinder 55 via a solenoid valve 54 An exhaust duct 56 is connected to the exhaust port 52, and the end thereof is provided with a valve box 57 open upward. The bottom section of the box 57 is fitted with an exhaust valve 58 and when the internal pressure of the duct 56 exceeds the predetermined level, a valve body is pushed up to be open upward. According to this construction, the ingress of atmosphere through the valve 58 is prevented, and dew condensation is restrained. Also, when an excessive amount of gas is supplied due to an error in the valve 54, error state is detected with a temperature sensor S, and open/close dampers 35 and 36 are closed. Thereby preventing an article in a test chamber from being excessively cooled.
KOTANI YOSHIHIKO
KANAMORI IKUO
