| 摘要 |
PURPOSE:To make it possible to reduce the size of ink droplets eliminating piezoelectric vibrator by injecting ink in an unbalanced state with a proper change in the pressure of an air current added to an air chamber in response to an injection signal after it is kept balanced with an arifice. CONSTITUTION:An injection signal is fed to a solenoid valve 15 from an injection signal source 14 to release an air current 12 slightly on the side of an air chamber 5. The air current pressure Pa reduces and a higher ink pressure Pi causes an imbalance between the ink tip and the air current 12, so that the tip 18 of the ink projects to the air chamber 5 from an orifice 7. The ink is further pulled out with the air current 12 and finally injected from an injecting hole 8 in droplets 2, 2.... When the injection signal disappears, a solenoid valve 15 is closed and the air current pressure Pa in the air chamber 5 rises. This stops the injection of the ink droplets 2, 2... bringing a balance with the ink pressure Pi again thereby returning an ink head 1 to the normal state. |
