| 摘要 |
PURPOSE:To stably form an ink droplet, by generating ultrasonic vibration by a piezoelectric vibrator and generating an advance wave in the ink in an ink flow passage by said ultrasonic vibration through the piston member arranged in the ink flow passage. CONSTITUTION:An ultrasonic wave generator block 17 is mounted to one end of a cylindrical pipe 1 which is, in turn, engaged with and fixed to the ultrasonic wave generator block 17 and the leakage of ink between the block 17 and the cylindrical pipe 1 is prevented at the leading end of the cylindrical pipe 1 by an O-ring 14 and at the outer periphery thereof by an O-ring 19. The ink introduced from the ink introducing hole 2 provided to the ultrasonic wave generator block 17 by drilling is supplied into the cylindrical pipe 1 through the outer periphery of a piston 12. A driving ultrasonic wave is supplied to the high voltage electrode 11 held between sandwich-shaped PZT ceramics 13, 13 to apply drop forming vibration to the cylindrical pipe 1 by the piston 12. The jets injected from nozzles 4, 4... form ink droplets by ultrasonic vibration. |
