Patent ID: 8182059

Claim:
An image printing device, comprising: a transfer roller configured to transfer a printing medium in a transfer direction; a driving source which rotates the transfer roller; a first sensor configured to detect a rotation amount of the transfer roller; a printhead which performs image printing onto the printing medium transferred by the transfer roller; a carriage configured to move in a movement direction intersecting the transfer direction, the carriage being mounted with the printhead; a second sensor mounted to the carriage, the second sensor being configured to detect the printing medium; a reference member disposed at a position opposing to the second sensor; a drive transmission mechanism configured to move the reference member in conjunction with a rotation of the transfer roller; and a controller configured to control the driving source, the printhead, and the carriage, wherein the controller is configured to: move the carriage to a detection position where the second sensor detects the reference member; drive the driving source to move the reference member via the drive transmission mechanism; and determine the position of the origin of the transfer roller based on a detection result of the first sensor, and a detection result of the second sensor.