Temperature control apparatus

A temperature control apparatus for controlling an external load to a predetermined high temperature by regulating a circulating liquid having a boiling point higher than 100° ° C. to a temperature higher than 100° C. and supplying the circulating liquid to the load, the temperature control apparatus comprising:

• a tank storing circulating liquid and including a heater for heating the circulating liquid;
• a discharge channel connecting the tank and a circulating-liquid ejection port for discharging the circulating liquid to the load;
• a circulation pump that pumps the circulating liquid from the tank to the discharge channel;
• a return channel connecting a circulating-liquid return port that receives the circulating liquid returned from the load and the tank;
• a heat exchanger including a first heat exchange channel through which the circulating liquid flows and a second heat exchange channel through which coolant for cooling the circulating liquid in the first heat exchange channel;
• a cooling circulation forward path for supplying the circulating liquid from the tank to the first heat exchange channel of the heat exchanger;
• a cooling circulation reverse path for returning the circulating liquid cooled by the heat exchanger from the first heat exchange channel to the tank;
• a cooling pump that pumps the circulating liquid from the tank to the cooling circulation forward path;
• a coolant supply path for introducing the coolant to the second heat exchange channel of the heat exchanger;
• a coolant discharge path for discharging the coolant after the heat exchange from the second heat exchange channel;
• a discharge-side temperature sensor provided in the discharge channel to measure a temperature of the circulating liquid discharged to the load;
• and
• an electronic controller configured to set the temperature of the circulating liquid to be discharged to the load, the electronic controller being for controlling rotational speeds of the circulation pump and the cooling pump based on a measurement result of the discharge-side temperature sensor and the set temperature of the circulating liquid,
• wherein, in the heat exchanger, the first heat exchange channel includes a helical channel portion extending in a helical form along an axis, an inflow channel portion connected to one end of the helical channel portion and including a circulating-liquid inlet, and an outflow channel portion connected to the other end of the helical channel portion and including a circulating-liquid outlet, and the second heat exchange channel is a channel space formed in a hollow shell,
• wherein the helical channel portion of the first heat exchange channel is housed in the second heat exchange channel in the shell, the inflow channel portion and the outflow channel portion are let out from the shell, the cooling circulation forward path is connected to the circulating-liquid inlet, and the cooling circulation reverse path is connected to the circulating-liquid outlet,
• wherein the coolant supply path communicates with the second heat exchange channel through a coolant inlet provided on the shell, and the coolant discharge path communicates with the second heat exchange channel through a coolant outlet provided on the shell,
• wherein the circulation pump is immersed in the circulating liquid in the tank, and
• wherein the electronic controller is configured, when the set temperature of the circulating liquid is lower than a predetermined threshold temperature, to maintain the rotational speed of the circulation pump to a low rotational speed, and when the temperature is higher than the predetermined threshold temperature, to maintain the rotational speed of the circulation pump to a high rotational speed, and
• wherein the electronic controller is configured, when the set temperature of the circulating liquid is increased, to decrease the rotational speed of the cooling pump once and thereafter gradually increase the rotational speed, and when the set temperature is decreased, to increase the rotational speed of the cooling pump once and thereafter gradually decrease the rotational speed, and when the temperature of the circulating liquid measured by the discharge-side temperature sensor is equal to the set temperature, to maintain the rotational speed at that time.