An ink jet printer has a recovery system for sucking ink from nozzle orifices together with air bubbles stagnant in orifices so as to recover the normal state in the orifices. The recovery system has a vacuum generating device, a capping device and a valve mechanism for controlling the vacuum generated...http://www.google.de/patents/US4926196?utm_source=gb-gplus-sharePatent US4926196 - Ink jet printer
