Printing apparatus, control method for printing apparatus, and printing method

A control method for a printing apparatus for controlling an operation of the printing apparatus that carries out printing on a surface of a printing target object having a three-dimensional shape based on a print image, which is an image to be printed, wherein the printing apparatus comprises

• a printer head comprising a nozzle surface being a surface formed with a nozzle row where a plurality of nozzles, each of which discharges ink, are lined in a predetermined nozzle row direction,
• a target object holding device that holds the printing target object, the target
• a target object holding device that holds the printing target object, the target object holding device rotatably holding the printing target object with a rotating axis set in a three-dimensional space as a center,
• a three-dimensional movement supporting device that movably supports the target object holding device in the three-dimensional space, and
• a head movement supporting device that movably supports the printer head so that the nozzle surface passes a position facing the surface of the printing target object held by the target object holding device,
• for a control on the printing apparatus,
• a relative movement control, a control of relatively moving the printer head with respect to the printing target object held by the target object holding device by controlling the operation of the three-dimensional movement supporting device and the head movement supporting device, and
• a print control, a control on discharging of the ink from the printer head, the print control comprising setting a printing target point, which is a position where the ink is to be discharged from at least some nozzles in the nozzle row, on the surface of the printing target object, and discharging the ink from a nozzle in the nozzle row to the printing target point based on the print image in accordance with the control of the relative movement by the relative movement control are carried out;
• in the print control, for a process of setting the printing target point, at least
• an ideal landing point calculation process of calculating an ideal landing point, which is an ideal landing point of the ink discharged from the nozzle in the nozzle row, the ideal landing point calculation process calculating the ideal landing point based on a shape of the surface of the printing target object without limiting a condition that the plurality of nozzles are linearly lined in the nozzle row,
• an actual landing point calculation process of calculating an actual landing point, which is a landing point of the ink dischargeable from the nozzle in the nozzle row, the actual landing point calculation process calculating the actual landing point based on the shape of the surface of the printing target object under a condition that the plurality of nozzles are linearly lined in the nozzle row, and
• a printing target point setting process of setting the printing target point on the surface of the printing target object, the printing target point setting process setting the printing target point with respect to each position based on the ideal landing point and the actual landing point corresponding to each position on the surface of the printing target object are carried out;
• and
• when positions are shifted between the ideal landing point and the actual landing point corresponding to an identical position on the surface of the printing target object, a correction corresponding to a position shift amount is carried out to set the printing target point in the printing target point setting process.

A printing method for carrying out printing using a printing apparatus that carries out printing on a surface of a printing target object having a three-dimensional shape based on a print image, which is an image to be printed, wherein the printing apparatus comprises

• a printer head comprising a nozzle surface being a surface formed with a nozzle row where a plurality of nozzles, each of which discharges ink, are lined in a predetermined nozzle row direction,
• a target object holding device that holds the printing target object, the target object holding device rotatably holding the printing target object with a rotating axis set in a three-dimensional space as a center,
• a three-dimensional movement supporting device that movably supports the target object holding device in the three-dimensional space, and
• a head movement supporting device that movably supports the printer head so that the nozzle surface passes a position facing the surface of the printing target object held by the target object holding device,
• with respect to the printing apparatus,
• a relative movement control, a control of relatively moving the printer head with respect to the printing target object held by the target object holding device by controlling an operation of the three-dimensional movement supporting device and the head movement supporting device, and
• a print control, a control on discharging of the ink from the printer head, the print control comprising setting a printing target point, which is a position where the ink is to be discharged from at least some nozzles in the nozzle row, on the surface of the printing target object, and discharging the ink from a nozzle in the nozzle row to the printing target point based on the print image in accordance with the control of the relative movement by the relative movement control are carried out;
• in the print control, for a process of setting the printing target point, at least
• an ideal landing point calculation process of calculating an ideal landing point, which is an ideal landing point of the ink discharged from the nozzle in the nozzle row, the ideal landing point calculation process calculating the ideal landing point based on a shape of the surface of the printing target object without limiting a condition that the plurality of nozzles are linearly lined in the nozzle row,
• an actual landing point calculation process of calculating an actual landing point, which is a landing point of the ink dischargeable from the nozzle in the nozzle row, the actual landing point calculation process calculating the actual landing point based on the shape of the surface of the printing target object under a condition that the plurality of nozzles are linearly lined in the nozzle row, and
• a printing target point setting process of setting the printing target point on the surface of the printing target object, the printing target point setting process setting the printing target point with respect to each position based on the ideal landing point and the actual landing point corresponding to each position on the surface of the printing target object are carried out;
• and
• when positions are shifted between the ideal landing point and the actual landing point corresponding to an identical position on the surface of the printing target object, a correction corresponding to a position shift amount is carried out to set the printing target point in the printing target point setting process.