| 摘要 |
PURPOSE:To keep the deflected amount of ink constant at all times by maintaining the constant flow of ink even when the temperature and viscosity of ink are varied by feeding informatin from an ink flow rate detecting means back to a pressure pump to jet ink droplets. CONSTITUTION:A given charge is given to ink droplets produced by a piezoelectric vibrator 9 and the charge of the ink droplets is detected by electrostatic induction of a flow rate detecting key 37. The time taken from the charging of ink droplets to the detection is measured to detect the flow of ink. When the time becomes longer, the rotary shaft 25 of a pulse motor 24 capable of controlling rotation angles fixed by a pressure pump 22 and a stud 23 is turned, a stopper block 26 coupled with a rotary shaft 25 and a screw is moved along the stud 23 serving as a guide according to the rotation angles of the rotary shaft 25, and the stopping position of a rotation angles of the rotary shaft 25, and the stopping position of a plunger 27 is also moved. When a voltage is applied to a solenoid 28, the attractive force of the plunger 27 is increased due to the reduction of the gap with a fixed iron core 29, the pressure of the pressure chamber 34 is increased, and the flow rate of ink jetted from the nozzle 8 is quickened. |
