Patent ID: 8141978

Claim:
A printer apparatus comprising: a medium supporter to support a printing medium; a carriage to hold a printer head provided with a nozzle from which ink is to be ejected onto a printing surface of the printing medium; a carriage moving mechanism to move the carriage along the printing surface of the printing medium supported by the medium supporter; an acceleration detector configured to detect acceleration of vibration generated in the carriage; a determining device configured to determine whether a magnitude of the acceleration detected by the acceleration detector exceeds a first predetermined threshold value or a second predetermined threshold value; and a controller configured to control the carriage moving mechanism to restrict relative movement of the carriage when the determining device determines that the magnitude of the acceleration detected by the acceleration detector exceeds the first predetermined threshold value or the second threshold value, wherein the controller is configured to immediately stop movement of the carriage when the magnitude of the acceleration exceeds the first predetermined threshold value and to stop movement of the carriage after completion of a scanning pass of the carriage when the magnitude of the acceleration exceeds the second predetermined threshold value.