Liquid-jet printer device

A liquid-jet printer device for recording information on an information carrier in the form of characters or symbols including:

• a print head in which a plurality of liquid channels are arranged to discharge a series of droplets of liquid according to a predetermined pattern during predetermined printing periods, each liquid channel having:
• an outlet opening for discharge of the liquid under pressure;
• a valve assembly arranged within each said liquid channel, the valve assembly being switchable for opening and closing the liquid channel;
• and
• an inlet for connection of the liquid channel to a supply conduit;
• said printer device further comprising a pump arrangement to supply liquid under pressure to said supply conduit from a liquid source;
• means for maintaining an operating pressure in the supply conduit only during said printing periods during which printing occurs, and for pressure relief to atmospheric pressure or sub-atmospheric pressure during idle periods between said printing periods;
• and
• means to achieve a small return flow of liquid during said idle periods so that the outlet openings are substantially emptied of said liquid.