| 摘要 |
PURPOSE:To use a transistor having a low voltage and a small current by connecting a piezoelectric element, a resistor and a transistor in series to form a discharging circuit, and connecting the secondary winding of a transformer and a diode in series with the element and a charge signal transistor to the primary winding of the transformer. CONSTITUTION:When a charge signal is input to a transistor 8, it is turned ON, and since the secondary side of a transformer 7 is connected in reverse polarity, no current flows. Accordingly, a current at the primary side of the transformer 7 becomes the same as that flowing to a coil, becoming a triangular waveform. Then, when the signal is turned OFF, a counterelectromotive force is generated in the windings of the transformer 7, and a triangular waveform current flows. This current charges a piezoelectric element 13 to perform a printing. When a discharge signal is input to turn a transistor 15 ON, the element 13 is discharged. The inclination of the triangular waveform can be regulated by the design of the primary side of the transformer 7, and no large current flows to the transistor 8. Accordingly, the transistor 8 can be reduced in size. |
