Patent ID: 8177316

Claim:
An ink jet printing device, comprising: a printing medium conveying mechanism having a support surface configured to support a printing medium, and being configured to convey the printing medium in a specified direction; a head unit mounting an ink jet head; a head unit moving mechanism configured to move said head unit reciprocally in a direction orthogonal to the specified direction of the printing medium; and a controller, wherein said controller is configured to control feeding of the printing medium in the specified direction, moving said head unit in a direction of crossing the printing medium, discharging ink in a direction from said head unit toward the printing medium, and printing on the printing medium, and wherein a blower is disposed at least at a backward side in a printing moving direction of said head unit, out of both sides of said head unit, and said blower has an air injection unit configured to generate a horizontal air stream in a direction nearly at a right angle to the ink discharge direction toward a direction departing from an adjacent head unit, disposed at a lower side of the blower, wherein said ink jet printing device is configured to dry the ink on the printing medium by the horizontal air stream, and wherein said head unit moving mechanism is configured to move said head unit from a waiting position to a printing area and within the printing area reciprocally, and said blower is configured to communicate with a solenoid value opened and closed by said controller, and blowing is startable or stoppable by opening or closing of said solenoid valve, and said controller is configured to control said solenoid valve by stopping blowing by the blower when said head unit is at the waiting position or while moving from the waiting position to a specified printing area, starting blowing by said blower when said head unit is in the printing area, and stopping blowing by said blower when said head unit finishes printing on the printing medium.