| 摘要 |
PURPOSE:To compensate the temperature of ink sufficiently to a temperature change within the range of the operating temperature of 5-40 deg.C by changing over excitation voltage to the piezo-electric vibrator of the ink injection head while making a temperature close to 15 deg.C of the temperature of ink bound. CONSTITUTION:When an excitation level changer 10 is opened at the temperature of ink of 15 deg.C or lower, value corresponding to 5-15 deg.C is selected in an excitation voltage level by an excitation signal source 5, and applied to the piezo-electric vibrator 2 through an excitation amplifier 11, and ink drops 3' are ejected from the ink injection head 1. When the temperature of ink reaches 15 deg.C or higher, the changer 10 is closed, and a low excitation voltage level corresponding to 15-40 deg.C is selected. The changer 10 is formed by binary-coding the output of a temperature senser by means of a Schmidt circuit or switching a contact by means of a bimetal or the like. Accordingly, the range of the operating temperature normally used can be compensated sufficiently without employing a complicate controlling mechanism. |
