LIQUID EJECTION HEAD

Abstract

Disclosed is a liquid ejection head capable of performing a stable ejection operation at high speed even when thermal expansion of a valve supporting member occurs during liquid ejection. This is because the liquid ejection head allows the thermal expansion to influence supported valves only to a small extent, and a highly accurate and stable adhesion state to be obtained. To this end, first holes, second holes and slits are provided in the valve supporting member.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a liquid ejection apparatus provided with a liquid ejection head according to an embodiment of the present invention;

FIG. 2 is an exploded perspective view of a liquid ejection head according to an embodiment of the present invention;

FIG. 3 is a diagram showing a configuration of a liquid supply system of the liquid ejection apparatus according to the embodiment of the present invention;

FIG. 4 is a cross sectional perspective view of the vicinity of nozzles of the liquid ejection head of the present embodiment;

FIG. 5A is a view showing a state where a bank and valve seats are formed on a base plate. FIG. 5B is a view showing a state where an ultraviolet-ray photosensitive resin film is laminated on the bank and valve seats for forming nozzle walls. FIG. 5C is a view showing a state where the nozzle walls are formed by irradiating the ultraviolet-ray photosensitive film with ultraviolet rays;

FIG. 6A is a view showing a state where movable valves are attached to the valve seats, respectively. FIG. 6B is a view showing a state where a top plate is attached to the nozzle walls. FIG. 6C is a view showing a state of the element after the element is cut. FIG. 6D is a view showing a state of the element after the cut plane is grinded;

FIG. 7 is a transverse cross sectional view of the vicinity of the nozzles of the liquid ejection head of the present embodiment;

FIG. 8 is a cross sectional view showing a structure of the periphery of an ejection port of the liquid ejection head of the present embodiment;

FIG. 9A is a view showing a state of the element before electric energy is applied to a heater. FIG. 9B is a view showing a state where an air-bubble is generated in the liquid. FIG. 9C is a view showing a moment when the liquid is just ejected from the ejection port; and

FIG. 10 is a plane view schematically showing a valve supporting member and chipped portions provided therein in the embodiment of the present invention.

Claims

1. A liquid ejection head capable of ejecting a liquid by changing a position of a valve, which is integrally formed of a valve supporting member made of a plate, along with generation of an air-bubble caused by heating the liquid, and thus by leading growth of the air-bubble toward an ejection port from which the liquid is ejected, wherein the valve supporting member includes:first and second chipped portions which are positioned in an ejection direction of the liquid with a space interposed in between;a first area which is positioned between the first and second chipped portions, and which extends in a direction crossing the ejection direction; anda third chipped portion which is formed in an area including at least a part of the first area, and which extends over the entire area in the ejection direction in the first area.

2. The liquid ejection head according to claim 1, wherein the valve supporting member includes a plurality of aforementioned third chipped portions.

3. The liquid ejection head according to claim 1, wherein the valve supporting member includes a plurality of sets of the first, second and third chipped portions, and the first area in combination.

4. The liquid ejection head according to claim 1, wherein the valve supporting member includes: a second area in which at least one of the first and second chipped portions is positioned, and which extends in the direction crossing the ejection direction; anda fourth chipped portion formed in an area including at least a part of the second area.

5. The liquid ejection head according to claim 1, wherein at least one of the plurality of chipped portions forms a closed space in the valve supporting member.

6. The liquid ejection head according to claim 1, wherein at least one of the plurality of chipped portions forms an open space in a marginal area of the valve supporting member.

7. The liquid ejection head according to claim 1, wherein the plurality of chipped portions are arranged in a staggered manner.

8. The liquid ejection head according to claim 1, wherein the plurality of chipped portions have at least two different sizes.

9. The liquid ejection head according to claim 1, wherein the valve supporting member includes a plurality of marginal portions in a linear shape, anda size of one of the chipped portions positioned at least one of the plurality of marginal portions is smaller than that of the chipped portion positioned at a central portion of the valve supporting member.