Liquid ejection head and liquid ejection apparatus

1 . A liquid ejection head including an ejection port configured to eject liquid, a liquid reservoir configured to supply the liquid to the ejection port, and a pressure adjustment unit configured to adjust a pressure of the liquid reservoir,

wherein the pressure adjustment unit includes:

a pressure adjustment chamber communicating with the liquid reservoir,

an elastic deformation portion configured so that an inner volume thereof can be changed according to a pressure inside the pressure adjustment chamber, and

a support portion configured to support the elastic deformation portion on the liquid reservoir portion,

wherein an area at which the elastic deformation portion and the support portion are connected has higher rigidity than that of the elastic deformation portion,

wherein the support portion includes an opening communicating with the liquid reservoir, and

wherein the pressure adjustment chamber has a structure which is symmetrical about the opening.

2 . The liquid ejection head according to claim 1 ,

wherein, in the area at which the elastic deformation portion and the support portion are connected, a structure protruding from an inner wall of the area toward an inside of the pressure adjustment chamber is disposed.

3 . The liquid ejection head according to claim 2 ,

wherein, as the structure, a plurality of structures are disposed.

4 . The liquid ejection head according to claim 3 ,

wherein the structures are disposed so as to be symmetrical about the opening.

5 . The liquid ejection head according to claim 2 ,

wherein a width of the structure on a plane parallel to a plane on which the opening is formed is longer at a first position than at a second position, the first position being closer to the opening, and the second position being further away from the opening.

6 . The liquid ejection head according to claim 1 ,

wherein a thickness of the area at which the elastic deformation portion and the support portion are connected is thicker than the elastic deformation portion.

7 . The liquid ejection head according to claim 6 ,

wherein the thickness of the area at which the elastic deformation portion and the support portion are connected becomes thicker from an inner wall of the elastic deformation portion toward an inside of the pressure adjustment chamber.

8 . The liquid ejection head according to claim 1 ,

wherein the area at which the elastic deformation portion and the support portion are connected corresponds to a non-deformable area.

9 . The liquid ejection head according to claim 8 ,

wherein the area at which the elastic deformation portion and the support portion are connected is made of a material different from the elastic deformation portion.

10 . The liquid ejection head according to claim 8 ,

wherein the non-deformable area is configured by two-color molding with the elastic deformation portion.

11 . The liquid ejection head according to claim 1 ,

wherein the pressure adjustment chamber includes an opening portion in a circular shape and two surfaces that are flat in a state before deformation on an outer peripheral surface, and a distance between the two surfaces becomes smaller toward a leading end portion, which is on an opposite side of the opening portion.

12 . A liquid ejection apparatus comprising:

a liquid ejection head including an ejection port configured to eject liquid, a liquid reservoir configured to supply the liquid to the ejection port, and a pressure adjustment unit configured to adjust a pressure of the liquid reservoir;

a tank configured to store the liquid to be supplied to the liquid ejection head; and

a tube configured to connect the liquid ejection head and the tank,

wherein the pressure adjustment unit includes:

a pressure adjustment chamber communicating with the liquid reservoir,

an elastic deformation portion configured so that an inner volume thereof can be changed according to a pressure inside the pressure adjustment chamber, and

a support portion configured to support the elastic deformation portion on the liquid reservoir portion,

wherein an area at which the elastic deformation portion and the support portion are connected has higher rigidity than that of the elastic deformation portion,

wherein the support portion includes an opening communicating with the liquid reservoir, and

wherein the pressure adjustment chamber has a structure which is symmetrical about the opening.

13 . The liquid ejection apparatus according to claim 12 ,

wherein the liquid ejection head ejects the liquid while performing reciprocal movement.

14 . The liquid ejection apparatus according to claim 12 , further comprising:

a cap configured to cover the liquid ejection head; and

a pump configured to suction the liquid ejection head in a state in which the liquid ejection head is covered with the cap.