Patent ID: 7540578

Claim:
An inkjet recording apparatus, comprising: a plurality of recording heads, each of the recording heads having a plurality of nozzles selectively discharging ink and arranged at a predetermined pitch in a line, the plurality of recording heads being arranged in a zigzag fashion such that a disposition direction of the nozzles is parallel with a main scanning direction, respective ends of two adjacent recording heads being overlapped with each other to form a joint part, and ink being discharged from selected nozzles of the respective recording heads on print paper fed along a sub scanning direction at a predetermined timing corresponding to positions of the respective recording heads in the sub scanning direction for forming an in-line image continuous in the main scanning direction on the print paper, each of the two adjacent recording heads including expected ink discharging nozzles located in a middle portion of the recording head and having an end nozzle located at an end of the expected ink discharging nozzles, said end nozzle in one recording head of the two adjacent recording heads and said end nozzle in the other recording head being arranged to have a distance the same as the predetermined pitch in the main scanning direction so as to form the joint part in the in-line image, and each of the two adjacent recording heads further including at least one endmost nozzle adjacent to said end nozzle on a side opposite to the expected ink discharging nozzles, and a control unit for controlling a driving operation of the respective nozzles at the joint part depending upon a dispositional relation between the two end nozzles of the two adjacent recording heads at the joint part in the main scanning direction, wherein when the distance between the two end nozzles of the two adjacent recording heads is greater than the predetermined pitch, said expected ink discharging nozzles discharge an amount of ink equal to a normal amount of ink, and each of the at least one endmost nozzle discharges an amount of ink less than the normal amount of ink, and wherein when the distance between the two end nozzles of the two adjacent recording heads is the predetermined pitch, each of the at least one endmost nozzle does not discharge the ink.