摘要 |
PURPOSE:To maintain a constant delivery pressure by using a pulsationless rotary pump and controlling the revolution rate of a driving motor for the pump besed on temperature changes. CONSTITUTION:In an ink jet plotter, ink is converted into ink droplets by a head 5 under a pump pressure, and the flight direction of the droplets is controlled electrostatically. In the plotter, a pulsationless rotary pump 3 is used as the pump for applying a pressure to the head 5, and a driving motor 18 for the pump 3 is connected to a control unit 20 which detects the ink temperature by a temperature detector element 21 and determines the revolution rate of the motor 18. EFFECT:Uniform delivery pressure can be applied to the head even upon ink viscosity changes according to temperature changes; hence, staggered printing is prevented. |