Printing apparatus and bubble exhaust method therefor

A printing apparatus comprising:

• a printhead in which a plurality of orifices are provided for discharging ink;
• an ink tank for storing ink to be supplied to the printhead;
• an ink channel for supplying ink from the ink tank to the printhead;
• a bubble injection unit configured to perform a bubble injection operation to inject a bubble to the ink channel;
• a suction unit configured to perform a suction operation to suck ink from the printhead;
• a first control unit configured to cause the suction unit to perform the suction operation after causing the bubble injection unit to perform the bubble injection;
• and
• a second control unit configured to cause the suction unit to perform the suction operation without causing the bubble injection unit to perform the bubble injection operation.

A method for exhausting a bubble in a printing apparatus including:

• a printhead in which a plurality of orifices are provided for discharging ink;
• an ink tank for storing ink to be supplied to the printhead;
• an ink channel for supplying ink from the ink tank to the printhead;
• a bubble injection unit configured to perform a bubble injection operation to inject a bubble to the ink channel;
• and a suction unit configured to perform a first suction operation and a second suction operation that is stronger than the first suction operation to suck ink from the printhead, comprising:
• performing the bubble injection operation by the bubble injection unit;
• performing the first suction operation for a predetermined time by the suction unit;
• and
• performing the second suction operation by the suction unit.

A method for exhausting a bubble in a printing apparatus including:

• a printhead in which a plurality of orifices are provided for discharging ink;
• an ink tank for storing ink to be supplied to the printhead;
• an ink channel for supplying ink from the ink tank to the printhead;
• a bubble injection unit configured to perform a bubble injection operation to inject a bubble to the ink channel;
• and a suction unit configured to perform a suction operation to suck ink from the printhead, comprising:
• acquiring an elapsed time since a previous suction operation is performed by the suction unit;
• and
• determining whether or not to execute the bubble injection operation by the bubble injection unit before a next suction operation, based on the acquired elapsed time.