Valve assembly for controlling fluid flow within an ink-jet pen

A valve assembly for controlling fluid flow within an ink-jet printer printhead, the valve assembly comprising:

• a printhead base having a fluid channel that is in fluid communication with a nozzle through which ink droplets are expelled;
• a resiliently deformable valve member connected at a first end to the channel and movable into and out of a closed position for occluding fluid flow into and out of the nozzle when the valve is heated or cooled;
• and
• wherein ink within the channel is pressurized by an amount sufficient to expel ink through the nozzle such that when the valve member is moved out of the closed position an ink droplet is expelled from the nozzle.

A valve assembly for an ink-jet printer printhead, the assembly comprising:

• a printhead having a base and a nozzle through which ink droplets are ejected;
• a chamber formed in the base of the printhead for storing ink, a portion of the chamber disposed beneath the nozzle;
• a heat transducer mounted beneath the nozzle on a lower surface of the chamber for heating ink stored in the chamber to expel ink droplets through the nozzle;
• a fluid channel formed in the base of the printhead adjacent the heat transducer and forming a junction with the chamber;
• a valve member having a first end connected to the lower surface of the chamber for substantially occluding ink flow between the fluid channel and the chamber when the valve member is in a closed position, the valve member including a first surface having a first coefficient of thermal expansion and a second surface having a second coefficient of thermal expansion;
• and
• a heat-conducting layer which, when activated, heats the valve member causing a second end of the valve member to deform.