Patent ID: 8256860

Claim:
A printing apparatus provided with a heater for heating ink and a cooler for cooling ink, comprising: an ink circulation route including a heater side route and a cooler side route which are separately provided through the heater and the cooler respectively; a switch mechanism operable to switch the ink circulation route between the heater side route and the cooler side route; a control unit operable to control the switch mechanism; an ink thermometer operable to measure the temperature of the ink; and an ambient thermometer operable to measure the ambient temperature of the printing apparatus, wherein the control unit controls the switch mechanism to switch the ink circulation route to the heater side route when the ink temperature as measured is lower than a first reference temperature, and switch the ink circulation route to the cooler side route when the ink temperature as measured is higher than a second reference temperature which is higher than the first reference temperature, and wherein the control unit controls the switch mechanism to switch the ink circulation route to the heater side route when the ink temperature as measured is higher than the first reference temperature and lower than a second reference temperature and when the ambient temperature as measured is lower than the first reference temperature, and switch the ink circulation route to the cooler side route when the ambient temperature as measured is no lower than the first reference temperature.