The invented non-clogging cap and service station include a cap that encloses and defines a cavity around a printhead. The cap includes a basin to collect liquid discharged from the printhead and a vent to prevent changes of pressure within the cavity. Capillary spaces are constructed within the cap...http://www.google.de/patents/US5027134?utm_source=gb-gplus-sharePatent US5027134 - Non-clogging cap and service station for ink-jet printheads
