Liquid ejection head, liquid ejection apparatus, and temperature control method for liquid ejection head

A liquid ejection apparatus comprising:

• a liquid ejection head configured to eject a liquid through ejection ports;
• and
• a moving unit configured to move the liquid ejection head relative to a medium to which the liquid ejected from the liquid ejection head is applied,
• wherein the liquid ejection head comprises:
• ejection energy generation elements configured to generate energy utilized to eject the liquid;
• a detection unit configured to detect a temperature of the liquid ejection head;
• a heating unit configured to heat the liquid ejection head by a heating value varying according to a temperature difference between a temperature detected by the detection unit and a predetermined target temperature;
• a plurality of pressure chambers each configured to communicate with a corresponding one of a plurality of the ejection ports and containing one of the ejection energy generation elements;
• a common liquid supply path configured to communicate with one side of each of the plurality of pressure chambers;
• and
• a common liquid collection path configured to communicate with the other side of each of the plurality of pressure chambers,
• wherein the common supply path has a higher internal static pressure than the common collection path.

A temperature control method for a liquid ejection head enabled to eject a liquid through a plurality of ejection ports, the liquid ejection head including the ejection ports, a plurality of pressure chambers each configured to communicate with a corresponding one of the plurality of ejection ports and containing an ejection energy generation element, a common liquid supply path configured to communicate with one side of each of the plurality of pressure chambers, and a common liquid collection path configured to communicate with the other side of each of the plurality of pressure chambers, wherein the common supply path has a higher internal static pressure than the common collection path, the method comprising:

• a first detection step of detecting a temperature in a first area in which some of the plurality of ejection ports are disposed;
• a second detection step of detecting a temperature in a second area in which some of the plurality of ejection ports are disposed;
• and
• a heating step of heating the first area according to a temperature difference between a predetermined target temperature and the temperature detected in the first detection step and heating the second area according to a temperature difference between the predetermined target temperature and the temperature detected in the second detection step.

A liquid ejection head that ejects a liquid through ejection ports, the liquid ejection head comprising:

• ejection energy generation elements configured to generate energy utilized to eject the liquid;
• a detection unit configured to detect a temperature of the liquid ejection head, the detection unit including a first detection unit configured to detect a temperature in a first area and a second detection unit configured to detect a temperature in a second area;
• a heating unit configured to heat the liquid ejection head, the heating unit including a first heating unit configured to heat the first area and a second heating unit configured to heat the second area;
• a driving unit configured to allow the heating unit to generate heat by a heating value varying according to a temperature difference between a temperature detected by the detection unit and a predetermined target temperature;
• and
• a supply path through which the liquid is fed to a plurality of the ejection ports,
• wherein the driving unit allows the first heating unit to generate heat according to a temperature difference between the predetermined target temperature and a temperature detected by the first detection unit and allows the second heating unit to generate heat according to a temperature difference between the predetermined target temperature and a temperature detected by the second detection unit,
• the first area is positioned on an upstream side in the supply path with respect to the second area, and
• the driving unit sets the heating value of the first heating unit larger than the heating value of the second heating unit.