Patent ID: 7794044

Claim:
An ink jet printing apparatus comprising: a print head unit having a plurality of ejection portions; a first cap for capping a first ejection group including a first number of ejection portions out of the plurality of ejection portions; a second cap for capping a second ejection group including a second number, greater than the first number, of ejection portions out of the plurality of ejection portions; a first tube communicating with said first cap; a second tube communicating with said second cap; and a suction pump provided common to said first and second tubes for generating a negative pressure in said first and second caps, wherein an inner diameter of said second tube is larger than that of said first tube so that an amount of ink sucked out from each ejection portion included in the first ejection group is equal to an amount of ink sucked out from each ejection portion included in the second ejection group when ink is sucked out from the first and second ejection groups by said first and second caps.