Patent ID: 7837293
Filing Date: 2010-11-23
Classification: B41J

Abstract:
1. A suction device that is provided in an inkjet liquid droplet ejection apparatus to plot on a workpiece by a plurality of functional liquid droplet ejection heads and sucks functional liquid while contacting with nozzle surfaces of the functional liquid droplet ejection heads, the suction device comprising: a plurality of head caps corresponding to the plurality of functional liquid droplet ejection heads; a suction channel having a plurality of individual channels having their upstream sides connected to the plurality of head caps and a junction channel connected to downstream ends of the plurality of individual channels via a junction part; a plurality of channel opening/closing unit that is disposed on the individual channels and opens and closes the respective individual channels; a waste liquid tank connected to a downstream end of the junction channel and composed of a sealed tank; an ejector having a primary side with compressed air introduced thereto, and a secondary side connected to an upper space of the waste liquid tank; a pressure adjustment unit that adjusts pressure of the compressed air at the primary side of the ejector; and a control unit that controls the pressure adjustment unit, the control unit controlling the pressure adjustment unit according to a number of open-channel opening/closing units opened out of the plurality of channel opening/closing units such that a suction pressure is constant in the plurality of head caps.