| 摘要 |
PURPOSE:To hold pneumatic pressure balance for stably holding the meniscus generated at an ink emitting orifice, by supplying pneumatic pressure applied to an ink tank from a pneumatic chamber. CONSTITUTION:Air is sent to a penumatic chamber 7 form an air supply source 10 through an air supply passage 9 and a pneumatic layer is formed in an air outflow space 6 to flow out air from an air emitting port 3 at a constant flow speed. Pneumatic pressure applied to an ink tank 12 is supplied from the pneumatic chamber 7 through a pneumatic pressure supply passage 13. By this mechanism, even if the inner diameter of the tube for an air supply passage 9 is small and pressure loss is generated in the tube, this effect is not received and pressure of the ink tank 12 always becomes almost equal to that of the pneumatic chamber 7. Because the effect of the variation in pneumatic pressure due to the change in temp. or a change with the elapse of time is received, pneumatic pressure balance for stably holding the meniscus of ink generated at an ink emitting orifice can be held. |
