| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that ink is uselessly consumed since a negative pressure recovery operation is performed even when negative pressure is normal, when air is mixed into a sub-tank. SOLUTION: The amount of gas in the sub-tank 35 supplying the ink to a recording head 34 is detected by detecting electrode pins 208a and 208b, to be detected as the displacement amount of a displacement member 205 detecting the displacement amount of the elastic member 204 of the sub-tank 35. When the gas amount is a predetermined gas amount VGa or more and the displacement amount is below a predetermined displacement amount La, on the basis of the detected gas amount and displacement amount, the ink is supplied into the sub-tank 35 and then, a negative pressure forming operation is performed, in such a state that opening to the air through the air opening mechanism 207 of the sub-tank 35 is performed. When the gas amount is the predetermined gap amount VGa or more and the displacement amount is the predetermined displacement amount La or more, control not to perform the negative pressure forming operation is performed. COPYRIGHT: (C)2010,JPO&INPIT |
