Abstract: An ink tank apparatus having a reservoir for containing ink, is improved to control or eliminate the harmful effects of foaming, misting and splatter of ink in the ink tank. A fluid pump delivers ink to a printer system, having an associated reservoir, and a vacuum pump acts on the reservoir to return unused ink from the printer to the reservoir. The returning ink is caused to enter the reservoir at an angle so the returned ink tends to stay near a surface of the reservoir ink level. In particular a ramp or series of ramps are provided along which the returning ink travels. Furthermore, the returned ink is ported into a confined inlet chamber from which the returned ink drains into the ink tank, and the returned ink is ported into this confined inlet chamber so as to produce a vortex-like flow in the inlet chamber. A drain port from the inlet chamber can be restricted to reduce pulsations in the returned flow, and baffles can be used to inhibit the flow of mist to the vacuum port of the ink tank.

Abstract: A modular print head system for continuous ink jet printer apparatus includes a droplet stream generator, a droplet charger and a droplet catcher constructed as a module that includes ink supply and return line coupling devices, each having engagement openable valves, resonator and charge plate connectors, and index surfaces for accurately positioning of the module. A nest assembly of the system includes ink supply and return ports, droplet generator and charging power terminals, structure for supporting and accurately positioning a print head module. The nest assembly further includes a camming device which is movable to engage a supported module into an operative relation with the ink lines coupled to the ports, the valves open, the droplet generator and charger connected and to nest power terminals and the module index surfaces in contact with the positioning structure of the nest assembly.

Abstract: Ink jet printing apparatus having an improved system for start-up or maintenance includes elements for adjusting ink flow to impact on lower print head structure and elements for thereafter air skiving the ink from that structure.