Patent ID: 7959274

Claim:
A cartridge unit for an inkjet printer, the cartridge unit comprising: a printhead having an array of ink ejection nozzles; a plurality of ink storage compartments, each ink storage compartment having a variable storage volume and a displaceable wall section biased to expand the variable storage volume to generate a sustained negative pressure; an ink feed system for connecting the ink storage compartment to the printhead, the ink feed system including a plurality of channels extending parallel to a length of the printhead, each channel corresponding respectively to an ink storage compartment; and a printhead maintenance assembly, the printhead maintenance assembly having a capper spring biased against the array of ink ejection nozzles for covering the array of ink ejection nozzles, wherein, the printhead maintenance assembly includes a catch element engaged with an actuator, the catch element being movable by the actuator in a direction to counteract the biasing of the capper against the array of ink ejection nozzles, each ink storage compartment has an interface for receiving a refill unit for refilling the ink storage compartment, the interface having an inlet valve biased to a closed position for receiving ink into a respective ink storage compartment, and an open outlet valve biased to an open position for communicating ink from a respective ink storage compartment to the printhead, and the cartridge unit further comprises a pair of valve actuator pins provided in the interface of each ink storage compartment, the pair of valve actuator pins adapted to engage with a refill unit received by the interface to substantially simultaneously actuate the inlet valve to an opened position and actuate the outlet valve to a closed position.