Discharge head, discharge unit, and liquid discharge apparatus

Patent metadata

Field	Value
Publication number	US-12502887-B2
Application number	US-202117791553-A
Country	US
Kind code	B2
Filing date	Mar 16, 2021
Priority date	Mar 23, 2020
Publication date	Dec 23, 2025
Grant date	Dec 23, 2025

Abstract

A discharge head includes a nozzle, a valve body, a piezoelectric element, and a first biasing unit. The nozzle is configured to discharge liquid. The valve body is configured to open and close the nozzle. The piezoelectric element is configured to drive the valve body. The first biasing unit is disposed in parallel with the piezoelectric element. The piezoelectric element is configured to drive the valve body in a direction to open the nozzle when a voltage is applied to the piezoelectric element. The first biasing unit is configured to bias the valve body in the direction to open the nozzle.

First claim

The invention claimed is:

1 . A discharge head, comprising:
a nozzle to discharge liquid; a valve body to open and close the nozzle; a piezoelectric element to drive the valve body; a structure to displace the piezoelectric element and the valve body in a direction to close the nozzle; and a first biasing structure having two end portions, wherein the piezoelectric element is to drive the valve body in the direction to close the nozzle when a voltage is applied, wherein the first biasing structure includes an elastically deformable spring portion at each of the two end portions in a direction in which the piezoelectric element extends or contracts, wherein the elastically deformable spring portions each include a plurality of slits, wherein the elastically deformable spring portions have different spring constants, wherein the plurality of slits of each of the elastically deformable spring portions are provided alternatively along the direction in which the piezoelectric element extends or contracts such that the elastically deformable spring portions each have an s-shape, wherein the first biasing structure includes a rigid portion disposed between the elastically deformable spring portions, wherein a first one of the elastically deformable spring portions is disposed at a first end of the rigid portion, wherein a second one of the elastically deformable spring portions is disposed at a second end of the rigid portion, wherein a length in the direction in which the piezoelectric element extends or contracts from the first end of the rigid portion to the second end of the rigid portion is longer than at least two times a total length of one of the first one of the elastically deformable spring portions or the second one of the elastically deformable spring portions in the direction in which the piezoelectric element extends or contracts, wherein the rigid portion has consistent rigidity and cross section from the first end of the rigid portion to the second end of the rigid portion along the direction in which the piezoelectric element extends or contracts, wherein, in response to expansion and contraction of the piezoelectric element, the elastically deformable spiring portions are deformable along the direction in which the piezoelectric element extends or contracts, and wherein, with respect to the expansion and contraction of the piezoelectric element, the rigid portion is rigid in the direction in which the piezoelectric element extends or contracts.

2 . The discharge head according to claim 1 ,
wherein the first biasing structure is disposed side by side with the piezoelectric element in the direction in which the piezoelectric element extends or contracts, and wherein the first biasing structure is to bias the valve body in the direction to open the nozzle.

3 . The discharge head according to claim 1 , further comprising:
a second biasing structure disposed in in an area extending from the piezoelectric element along the direction in which the piezoelectric element extends or contracts, wherein the second biasing structure is to bias the valve body in the direction to close the nozzle.

4 . The discharge head according to claim 1 , further comprising:
a guide member to guide movement of the valve body.

5 . The discharge head according to claim 1 , further comprising:
a channel to which pressurized liquid is supplied, the channel being communicated with the nozzle; and a displacement plate partitioning between the piezoelectric element and the channel, wherein the displacement plate is to displace with movement of the valve body.

6 . A discharge unit, comprising:
the discharge head according to claim 1 .

7 . A liquid discharge apparatus, comprising:
the discharge unit according to claim 6 .

8 . A liquid discharge apparatus, comprising:
the discharge head according to claim 1 .

9 . The discharge head according to claim 1 , wherein a number of the plurality of slits at a first end portion of the end portions is different from a number of the plurality of slits at a second end portion of the end portions.

10 . The discharge head according to claim 1 , wherein a distance between two slits of the plurality of slits at a first end portion of the end portions is different from a distance between two slits of the plurality of slits at a second end portion of the end portions.

11 . The discharge head according to claim 1 , wherein the first biasing structure is a plate spring.

12 . The discharge head according to claim 1 ,
wherein the first biasing structure includes two parallel plate portions which extend in the direction in which the piezoelectric element extends or contracts, wherein each of the two parallel plate portions has two end portions, wherein each of the two parallel plate portions includes an elastically deformable spring portion at each of the two end portions, and wherein the piezoelectric element is disposed between the two parallel plate portions.

13 . The discharge head according to claim 1 , wherein the rigid portion is a plate.

14 . The discharge head according to claim 1 , wherein the rigid portion has a uniform width from the first end of the rigid portion to the second end of the rigid portion along the direction in which the piezoelectric element extends or contracts.

15 . The discharge head according to claim 1 , wherein the length in the direction in which the piezoelectric element extends or contracts from the first end of the rigid portion to the second end of the rigid portion is longer than at least three times the total length of one of the first one of the elastically deformable spring portions or the second one of the elastically deformable spring portions in the direction in which the piezoelectric element extends or contracts.

16 . The discharge head according to claim 1 , wherein the length in the direction in which the piezoelectric element extends or contracts from the first end of the rigid portion to the second end of the rigid portion is longer than at least four times the total length of one of the first one of the elastically deformable spring portions or the second one of the elastically deformable spring portions in the direction in which the piezoelectric element extends or contracts.

17 . The discharge head according to claim 1 , wherein the length in the direction in which the piezoelectric element extends or contracts from the first end of the rigid portion to the second end of the rigid portion is longer than at least five times the total length of one of the first one of the elastically deformable spring portions or the second one of the elastically deformable spring portions in the direction in which the piezoelectric element extends or contracts.

Assignees

• Matsufuji Ryohta
• Amari Kiyoshi
• Honda Ryo
• Sakai Keitaroh
• Ricoh Co Ltd

Inventors

• Matsufuji Ryohta
• Amari Kiyoshi
• Honda Ryo
• Sakai Keitaroh

Classifications

• B41J2202/12

  with ink circulating through the whole print head · CPC title

• B41J2202/05

  Heads having a valve · CPC title

• B41J2/14201 Primary

  Structure of print heads with piezoelectric elements · CPC title