US-12623457-B2 - Ink supply structure for inkjet head

US12623457B2US 12623457 B2US12623457 B2US 12623457B2US-12623457-B2

Abstract

An inkjet head includes an ejector unit that ejects ink in accordance with a driving signal and a drive substrate unit that outputs the driving signal. The ejector unit includes a base plate, an internal tank temporarily storing the ink ejected from an ejection outlet, a feed ink line that passes the ink supplied to the internal tank, and a first opening. The first opening is formed in an exposed portion of the base plate and communicates to the internal tank. The feed ink line is connected to the first opening at the end on one side in the axial direction and extends toward the other side in the axial direction along the side wall of the case. The end of the feed-side ink line on the other side in the axial direction is located on the side closer to the other side than the top plate of the case.

Inventors

Takanori Tsuji
Tomonori YASUDA
Shigeki Matsuo
Masaru Iwabuchi

Assignees

SCREEN Holdings Co., Ltd.
KYOCERA CORPORATION

Dates

Publication Date: 20260512
Application Date: 20220721
Priority Date: 20210924

Claims (8)

1 . An inkjet head for performing printing on a printing medium by ejecting ink onto the printing medium, the inkjet head comprising: an ejector unit that ejects the ink in accordance with a driving signal; and a drive substrate unit that supplies the driving signal to the ejector unit, wherein the ejector unit includes: a base plate; an ejector that ejects the ink from an ejection outlet to the base plate, the ejector being arranged in the base plate; and an ejector-side connector that receives the driving signal, the drive substrate unit includes: a drive substrate that generates the driving signal; a drive-substrate-side connector that outputs the driving signal; and a case that holds the drive substrate and the drive-substrate-side connector, the drive substrate unit is detachable from the ejector unit in an axial direction orthogonal to the base plate, when the case is mounted on the ejector unit, the drive-substrate-side connector and the ejector-side connector are connected to each other and form an exposed portion that exposes part of the base plate, the ejector includes: an internal tank that temporarily stores the ink ejected from the ejection outlet; and a head body where the internal tank is arranged therein and has a side wall being in parallel with the axial direction, the ejector unit further includes: a feed ink line that passes the ink supplied to the internal tank; and a first opening formed in the exposed portion and communicating to the internal tank, the case includes: a side wall that expands into a cylinder shape towards one side in the axial direction; and a top plate that covers an end of the side wall on the other side in the axial direction opposite to the one side in the axial direction, the end being away from the base plate, the feed ink line is connected to the first opening at an end on the one side in the axial direction and extends toward the other side along the side wall, the end on the other side in the axial direction is located on a side closer to the other side than the top plate, and when the case is mounted on the ejector unit, the side wall of the case has an inner surface being contact with the side wall of the head body.
2 . The inkjet head according to claim 1 , wherein the drive substrate unit further includes a locking member fixedly attached to the side wall of the case, the locking member detachably locking an intermediate portion of the feed ink line in the axial direction.
3 . The inkjet head according to claim 1 , wherein the ejector unit further includes: an exhaust ink line that passes the ink exhausted from the internal tank; and a second opening formed in the exposed portion and communicating to the internal tank, and the exhaust ink line is connected to the second opening at an end on the one side in the axial direction and extends toward the other side along the side wall.
4 . The inkjet head according to claim 3 , wherein the internal tank includes a first internal tank on an ink feed side and a second internal tank on an ink exhaust side, the first internal tank communicates to the ejection outlet and the first opening, and the second internal tank communicates to the ejection outlet and the second opening.
5 . The inkjet head according to claim 3 , wherein the drive substrate unit further includes: a cooling jacket that cools the drive substrate by passing a cooling medium therein, the cooling jacket being arranged between the drive substrate and an inner surface of the case; a feed cooling line that passes the cooling medium supplied to the cooling jacket; and a connection port formed in the side wall and connected to the cooling jacket, the feed cooling line is connected to the connection port at an end on the one side and extends toward the other side along the side wall, and when the ejector unit and the drive substrate unit are mounted on each other, the connection port is separated from the first opening and the second opening in the axial direction.
6 . The inkjet head according to claim 1 , wherein the case has four side walls that expand into a square cylinder shape in the axial direction; the four side walls include: a pair of wide-face walls facing each other; and a pair of narrow-face walls facing each other and having a smaller surface area than the pair of wide-face walls, the feed ink line extends toward the other side in the axial direction along and on the side of one of the narrow-face wall.
7 . The inkjet head according to claim 1 , wherein the case has four side walls that expand into a square cylinder shape in the axial direction; the head body has a four side walls that expand into a square cylinder shape in the axial direction, the square cylinder configured by the four side walls of the case is slightly larger than the square cylinder configured by the four side walls of the head body.
8 . The inkjet head according to claim 1 , wherein the base plate is a plate-like member that expands in a longitudinal direction, perpendicular to the axial direction, and expands in a transverse direction, also perpendicular to the axial direction, the case has a four side walls that expand into a square cylinder shape in the axial direction; the four side walls include: a pair of wide-face walls being parallel to the longitudinal direction and facing each other; and a pair of narrow-face walls being parallel to the transverse direction, facing each other and having a smaller surface area than the pair of wide-face walls, the first opening is formed at one end of the base plate in the longitudinal direction, and the feed ink line extends toward the other side in the axial direction along the narrow-face wall on one side of the longitudinal direction of the pair of narrow-face walls, on the one side of the longitudinal direction, relative to the head body, but not along the narrow-face wall on the other side of the longitudinal direction or the pair of wide-face walls.

Description

This application is the U.S. National Phase under 35 U.S.C. § 371 of International Patent Application No. PCT/JP2022/028395, filed on Jul. 21, 2022, which in turn claims the benefit of Japanese Patent Application No. 2021-156146, filed on Sep. 24, 2021, the entire disclosures of which Applications are incorporated by reference herein. TECHNICAL FIELD The present invention relates to an inkjet head for performing printing by ejecting ink onto a printing medium. BACKGROUND ART There are known to be inkjet printing devices that print characters or images on a printing medium being transported in a predetermined direction, by ejecting ink from ejection outlets onto the printing medium. Such printing devices include an ejector that ejects ink from ejection outlets. The ejector includes therein an internal tank that temporarily stores the ink and an ink flow path that connects the internal tank to an external device outside the ejector. For example, the recording device (1) disclosed in Patent Literature (PTL) 1 is configured such that an ejector housing unit (20) that houses recording heads (7) capable of ejecting ink includes an ink flow path (46) (liquid flow path) that connects an ink cartridge (liquid housing unit) to the recording heads 7 capable of ejecting ink (liquid). CITATION LIST Patent Literature PTL 1: Japanese Patent Application Laid-Open No. 2017-081049 SUMMARY OF INVENTION Technical Problem In the recording device (1) disclosed in PTL 1, the ink flow path (46) formed in the ejector housing unit (20) opens to the side wall of the ejector housing unit (20). Thus, when the ink cartridge is replenished with ink supplied from an external ink supplier, lines or the like extending from the ink supplier have to be connected to the opening of the ink flow path 46 formed in the side wall of the ejector holder (20). Thus, an operator has to perform this connection operation on the lateral side of the ejector housing unit (20) where there is a limited space. This makes the operation difficult and may result in deterioration of operating efficiency. The present invention has been made in light of such circumstances, and it is an object of the present invention to provide a technique that enables easily establishing connection between an ejector and a line extending from an external ink supplier in the case of supplying ink to the internal tank that is located inside the ejector and temporarily stores the ink. Solution to Problem To solve the problem described above, a first aspect of the present application is an inkjet head for performing printing on a printing medium by ejecting ink onto the printing medium. The inkjet head includes an ejector unit that ejects the ink in accordance with a driving signal, and a drive substrate unit that supplies the driving signal to the ejector unit. The ejector unit includes a base plate, an ejector that ejects the ink from an ejection outlet to the base plate, the ejector being arranged in the base plate, and an ejector-side connector that receives the driving signal. The drive substrate unit includes a drive substrate that generates the driving signal, a drive-substrate-side connector that outputs the driving signal, and a case that holds the drive substrate and the drive-substrate-side connector. The drive substrate unit is detachable from the ejector unit in an axial direction orthogonal to the base plate. When the case is mounted on the ejector unit, the drive-substrate-side connector and the ejector-side connector are connected to each other and form an exposed portion that exposes part of the base plate. The ejector includes an internal tank that temporarily stores the ink ejected from the ejection outlet. The ejector unit further includes a feed ink line that passes the ink supplied to the internal tank, and a first opening formed in the exposed portion and communicating to the internal tank. The case includes a side wall that expands into a cylinder shape in the axial direction, and a top plate that covers an end of the side wall on one side in the axial direction, the end being away from the base plate. The feed ink line is connected to the first opening at an end on the other side in the axial direction opposite to the one side in the axial direction and extends toward the one side along the side wall, and the end on the one side in the axial direction is located on a side closer to the one side than the top plate. A second aspect of the present application is the inkjet head according to the first aspect, in which the drive substrate unit further includes a locking member fixedly attached to the side wall of the case, the locking member detachably locking an intermediate portion of the feed ink line in the axial direction. A third aspect of the present application is the inkjet head according to the first or second aspect, in which the ejector unit further includes an exhaust ink line that passes the ink exhausted from the internal tank, and a second opening fo