Liquid discharge head and liquid discharge apparatus

Patent metadata

Field	Value
Publication number	US-12325237-B2
Application number	US-202318205572-A
Country	US
Kind code	B2
Filing date	Jun 5, 2023
Priority date	Jun 10, 2022
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

Abstract

A liquid discharge head includes: a nozzle plate having multiple nozzle holes from which a liquid is to be discharged in a liquid discharge direction, the multiple nozzle holes arrayed in a nozzle array direction orthogonal to the liquid discharge direction; and a pressure chamber communicating with the multiple nozzle holes, wherein a volume V min of a virtual hemisphere S 1 is 5×10 5 μm 3 or more and 5×10 6 μm 3 or less, and a volume V max of a virtual hemisphere S 2 is five times or more and less than 1000 times the volume V min , each of the multiple nozzle holes has a virtual center line, and the nozzle plate has an inner surface defining a wall of the pressure chamber, the inner surface having multiple openings of each of the multiple nozzle holes.

First claim

The invention claimed is:

1. A liquid discharge head comprising:
a nozzle plate having multiple nozzle holes from which a liquid is to be discharged in a liquid discharge direction, the multiple nozzle holes arrayed in a nozzle array direction orthogonal to the liquid discharge direction; and
a pressure chamber communicating with the multiple nozzle holes,
wherein a volume V min of a virtual hemisphere S 1 is 5×10 5 μm 3 or more and 5×10 6 μm; or less, and
a volume V max of a virtual hemisphere S 2 is five times or more and less than 1000 times the volume V min ,
each of the multiple nozzle holes has a virtual center line,
the nozzle plate has an inner surface defining a wall of the pressure chamber, the inner surface having multiple openings of each of the multiple nozzle holes,
a spherical center is at an intersection between the virtual center line and an extension surface extended from the inner surface over the multiple openings,
the pressure chamber has surfaces:
in both directions in the nozzle array direction from the spherical center;
in a direction opposite to the liquid discharge direction from the spherical center; and
in both directions orthogonal to the nozzle array direction and orthogonal to the liquid discharge direction from the spherical center, and
the virtual hemisphere S 1 has a radius r min centered in the spherical center, the radius r min having the shortest length from the spherical center to any one of the surfaces of the pressure chamber, and
the virtual hemisphere S 2 has a radius r max centered in the spherical center, the radius r max having the longest length from the spherical center to any one of the surfaces of the pressure chamber.

2. The liquid discharge head according to claim 1 ,
wherein, each of the nozzle holes has a radius r 1 ,
the radius r min is three times or more and less than seven times the radius r 1 , and
the radius r max is five times or more and less than 60 times the radius r 1 .

3. The liquid discharge head according to claim 1 ,
wherein the inner surface has an area of 5×10 4 μm 2 or more and 2×10 5 μm 2 or less.

4. The liquid discharge head according to claim 1 ,
wherein a volume of the pressure chamber is 10 nl or less.

5. The liquid discharge head according to claim 1 ,
wherein the nozzle plate has a thickness of 25 μm or more and 45 μm or less.

6. The liquid discharge head according to claim 1 , wherein each of the multiple nozzle holes has a cross sectional area of 300 μm 2 or more and 360 μm 2 or less in a direction orthogonal to the liquid discharge direction.

7. The liquid discharge head according to claim 1 ,
wherein the liquid in the pressure chamber is not circulated and discharged from the multiple nozzle holes.

8. The liquid discharge head according to claim 1 , wherein the liquid is ink containing water, an organic solvent, and pigment.

9. A liquid discharge apparatus comprising:
the liquid discharge head according to claim 1 ; and
a conveyor configured to convey a medium to the liquid discharge head,
wherein the liquid discharge head discharges the liquid onto the medium conveyed by the conveyor.

Assignees

• Hatta Chikako
• OSANAI Shinichiroh
• Akiyama Kohta
• Ricoh Co Ltd

Inventors

• Hatta Chikako
• OSANAI Shinichiroh
• Akiyama Kohta

Classifications

• B41J2202/11

  characterised by specific geometrical characteristics · CPC title

• B41J2/1433 Primary

  Structure of nozzle plates · CPC title

• B41J2/14274 Primary

  of stacked structure type, deformed by compression/extension and disposed on a diaphragm · CPC title