Patent ID: 6857725

Claim:
A dot recording device for recording dots on a surface of a print medium using a dot recording head equipped with dot-forming element groups comprising a plurality of dot-forming elements for ejecting drops of ink, the device comprising: a main scan drive unit which drives the dot recording head and/or the print medium to perform main scanning; a head drive unit which drives at least part of the plurality of dot-forming elements to form dots during the main scan; a platen arranged extending in a direction of the main scan so as to face the plurality of dot-forming elements in at least part of a path of the main scan, and supporting the print medium so as to face the dot recording head; a sub-scan drive unit which drives at intervals between the main scans the print medium in a direction intersecting the direction of the main scan to perform sub-scanning; and a control unit for controlling the main scan drive unit, the head drive unit, and the sub-scan drive unit, wherein the plurality of dot-forming elements comprise: a first dot-forming element sub-group; and a second dot-forming element sub-group being located downstream from the first dot-forming element sub-group in a direction of the sub-scan, and the platen comprises a recessed portion arranged extending in the direction of the main scan at a location facing the second dot-forming element sub-group, wherein the control unit includes an upper edge printing unit, an intermediate printing unit, and an upper edge transition printing unit, when it is assumed that the surface of the print medium is divided, in order from a top, into an upper edge portion that includes an upper edge, an upper edge transition portion, an intermediate portion, a lower edge transition portion, and a lower edge portion that includes a lower edge, the upper edge printing unit performs upper edge printing for forming dots in the upper edge portion in an upper edge portion sub-scan mode using the second dot-forming element sub-group and without using the first dot-forming element sub-group; the intermediate printing unit performs intermediate printing for forming dots in the intermediate portion in an intermediate portion sub-scan mode using the first and second dot-forming element sub-groups, the intermediate portion sub-scan mode having a sub-scan maximum feed distance that is greater than a sub-scan maximum feed distance in the upper edge portion sub-scan mode; and the upper edge transition printing unit performs upper edge transition printing for forming dots in the upper edge transition portion in an upper edge transition portion sub-scan mode using the first and second dot-forming element sub-groups, the upper edge transition portion sub-scan mode having a sub-scan maximum feed distance that is smaller than the sub-scan maximum feed distance in the intermediate portion sub-scan mode.