Patent ID: 6511144
Filing Date: 2003-01-28
Classification: B41J

Abstract:
A dot-recording device for recording ink dots on a surface of a print medium, wherein the surface of the print medium being dividable in order from a front edge, into a front-edge portion containing the front edge, a front-edge transitional portion, an intermediate portion, a rear-edge transitional portion, and a rear-edge portion containing a rear edge, the dot recording device recording with the aid of a dot-recording head provided with a group of dot-forming elements for ejecting ink droplets, the dot-recording device comprising:a main scanning unit configured to drive the dot-recording head and/or the print medium to perform main scanning: a head driver configured to drive at least some of the dot-forming elements to form dots during the main scanning; a platen configured to extend in a main scanning direction and to be disposed opposite the dot-forming elements at least along part of a main scan path, the platen being configured to support the print medium at a position opposite the dot-recording head; a sub-scanning unit configured to move the print medium to perform sub-scanning in between main scan paths; and a controller configured to control the dot-recording device, wherein the platen comprises: a first support member extending in the main scanning direction, a width of the first support member in a sub-scanning direction corresponding to a first sub-scanning range on a surface of the dot-recording head including a preselected first sub-group of dot-forming elements; a first slot extending in the main scanning direction, a width of the first slot in the sub-scanning direction corresponding to a second sub-scanning range on the surface of the dot-recording head including a preselected second sub-group of dot-forming elements, the second sub-group of dot-forming elements being disposed in the sub-scanning direction downstream from the first sub-group of dot-forming elements; a second support member extending in the main scanning direction, a width of the second support member in the sub-scanning direction corresponding to a third sub-scanning range on the surface of the dot-recording head including a preselected third sub-group of dot-forming elements, the third sub-group of dot-forming elements being disposed in the sub-scanning direction downstream from the second sub-group of dot-forming elements; and a second slot extending in the main scanning direction, a width of the second slot in the sub-scanning direction corresponding to a fourth sub-scanning range on the surface of the dot-recording head including a preselected fourth sub-group of dot-forming elements, the fourth sub-group being disposed in the sub-scanning direction downstream from the third subgroup of dot-forming elements, wherein the controller comprises: a front-edge printing unit configured to form dots in the front edge portion in accordance with a first sub-scanning mode using the fourth sub-group of dot-forming elements without use of any of the first to third sub-groups of dot-forming elements; a front-edge transitional printing unit configured to form dots in the front-edge transitional portion in accordance with the first sub-scanning mode using the first to fourth sub-groups of dot-forming elements; an intermediate printing unit configured to form dots in the intermediate portion using the first to fourth sub-groups of dot-forming elements in accordance with a second sub-scanning mode, a maximum sub-scan feed amount in the second sub-scanning mode being greater than a maximum sub-scan feed amount in the first sub-scanning mode.