| 摘要 |
PURPOSE:To keep the temperature of an apparatus at a prescribed value highly accurately by turning on/off a heat source on the basis of a detecting signal to change the temperature of working fluid in a controlling vessel and the volume of a gaseous phase in the vessel and to contact/separate between a contact plate and a radiation plate in an expansion vessel. CONSTITUTION:When a temperature sensor 26 detects that the temperature of an apparatus 1 reaches the upper limit of a set temperature, a control circuit 27 actuated by a detecting signal makes a heater 24a heat working fluid 10' in a controlling vessel 23 through a power supply 24b to heat the fluid 10' up to a temperature sufficiently higher than the set temperature of the apparatus 1. Consequently, the fluid 10' makes the contact plate 9 and the radiation plate 6 contact each other at a sufficiently high pressure to discharge 6 heat from the apparatus 1. When the sensor 26 detects that the temperature of the apparatus 1 is reduced lower than the prescribed value, the circuit 27 turns off the power supply 24b and the heater 24a stops to heat the fluid 10' to reduce the temperature of the fluid 10'. Consequently, the vapor pressure of the fluid 10' is reduced, the contact plate 9 is separated from the radiation plate 6 and the radiated variable of the radiation plate 6 is reduced, preventing the apparatus 1 from temperature drop. |
