Liquid ejecting apparatus and method for controlling liquid ejecting head

A liquid ejecting apparatus that ejects liquid supplied from a plurality of liquid containers that contains liquid of the same kind, the number of the liquid containers being denoted as P (where P is a natural number that is not less than 2), comprising:

• a plurality of discharging portions each of which has a plurality of nozzles aligned in parallel with a first direction, the number of the discharging portions being denoted as P×J (where J is a natural number), the nozzles of each of, or one of, the P×J discharging portions being located at positions in the first direction that are different from positions of the nozzles of the other discharging portions, or the other discharging portion, in the first direction;
• a group of discharging portions that includes a plurality of individual discharging portions each of which has a plurality of nozzles, the number of the individual discharging portions being denoted as P×K (where K is a natural number), the nozzles of each of the P×K individual discharging portions being located at positions in the first direction that are different from the positions of the nozzles of all of the P×J discharging portions in the first direction, the nozzles of each of, or one of, the P×K individual discharging portions being located at the same positions in the first direction as the nozzles of the other individual discharging portions, or the other individual discharging portion;
• a plurality of flow passages each of which is provided for the corresponding one of the P liquid containers, each of the P flow passages branching from the corresponding one of the P liquid containers in such a manner that the liquid container is in communication with at least one discharging portion, the number of which is denoted as J, and at least one individual discharging portion, the number of which is denoted as K, through the flow passage, a certain set of J discharging portions or a certain J discharging portion that is communicated through a certain flow passage being different from the other set thereof, the other sets thereof, the other, or the others that is/are communicated through the other flow passage or the other flow passages, a certain set of K individual discharging portions or a certain K individual discharging portion that is communicated through a certain flow passage being different from the other set thereof, the other sets thereof, the other, or the others that is/are communicated through the other flow passage or the other flow passages;
• and
• a controlling section that carries out control in such a manner that, let frequency of use of each of the P×J discharging portions be denoted as Ra, and let frequency of use of each of the P×K individual discharging portions be denoted as Rb, a ratio of Ra to Rb satisfies the following relation;
• Ra:Rb=1:1/(P×K).

A method for controlling a liquid ejecting head that ejects liquid supplied from a plurality of liquid containers that contains liquid of the same kind, the number of the liquid containers being denoted as P (where P is a natural number that is not less than 2), the liquid ejecting head including a plurality of discharging portions each of which has a plurality of nozzles aligned in parallel with a first direction, the number of the discharging portions being denoted as P×J (where J is a natural number), the nozzles of each of, or one of, the P×J discharging portions being located at positions in the first direction that are different from positions of the nozzles of the other discharging portions, or the other discharging portion, in the first direction, a group of discharging portions that includes a plurality of individual discharging portions each of which has a plurality of nozzles, the number of the individual discharging portions being denoted as P×K (where K is a natural number), the nozzles of each of the P×K individual discharging portions being located at positions in the first direction that are different from the positions of the nozzles of all of the P×J discharging portions in the first direction, the nozzles of each of, or one of, the P×K individual discharging portions being located at the same positions in the first direction as the nozzles of the other individual discharging portions, or the other individual discharging portion, and a plurality of flow passages each of which is provided for the corresponding one of the P liquid containers, each of the P flow passages branching from the corresponding one of the P liquid containers in such a manner that the liquid container is in communication with at least one discharging portion, the number of which is denoted as J, and at least one individual discharging portion, the number of which is denoted as K, through the flow passage, a certain set of J discharging portions or a certain J discharging portion that is communicated through a certain flow passage being different from the other set thereof, the other sets thereof, the other, or the others that is/are communicated through the other flow passage or the other flow passages, a certain set of K individual discharging portions or a certain K individual discharging portion that is communicated through a certain flow passage being different from the other set thereof, the other sets thereof, the other, or the others that is/are communicated through the other flow passage or the other flow passages, the controlling method characterized by carrying out control in such a manner that, let frequency of use of each of the P×J discharging portions be denoted as Ra, and let frequency of use of each of the P×K individual discharging portions be denoted as Rb, a ratio of Ra to Rb satisfies the following relation;

• Ra:Rb=1:1/(P×K).