Search

US-20260124839-A1 - LIQUID EJECTING APPARATUS AND LIQUID EJECTION HEAD

US20260124839A1US 20260124839 A1US20260124839 A1US 20260124839A1US-20260124839-A1

Abstract

A technique capable of circulating liquid while suppressing a pump drive voltage is provided. There is provided a liquid ejection head including: an ejection unit capable of ejecting liquid; and a circulation path configured to supply liquid to the ejection unit and to collect liquid that has not been ejected from the ejection unit, and the circulation path includes a plurality of pumps configured to pump liquid by displacing the volume of a pump chamber using a piezoelectric element or a solenoid.

Inventors

  • Yuji Tamaru

Assignees

  • CANON KABUSHIKI KAISHA

Dates

Publication Date
20260507
Application Date
20251029
Priority Date
20241101

Claims (20)

  1. 1 . A liquid ejecting apparatus comprising: a liquid ejection head comprising an ejection unit capable of ejecting liquid and a circulation path configured to supply liquid to the ejection unit and to collect liquid that has not been ejected from the ejection unit, wherein the circulation path includes a plurality of pumps configured to pump liquid by displacing a volume of a pump chamber using a piezoelectric element or a solenoid.
  2. 2 . The liquid ejecting apparatus according to claim 1 , wherein the plurality of pumps are driven in response to a same drive signal.
  3. 3 . The liquid ejecting apparatus according to claim 1 , wherein the plurality of pumps are provided in parallel in the circulation path.
  4. 4 . The liquid ejecting apparatus according to claim 1 , wherein the plurality of pumps are provided in series in the circulation path.
  5. 5 . The liquid ejecting apparatus according to claim 1 , wherein a portion of the plurality of pumps are provided in parallel in the circulation path and a remaining portion of the plurality of pumps are provided in series.
  6. 6 . The liquid ejecting apparatus according to claim 1 , wherein the plurality of pumps have a same configuration.
  7. 7 . The liquid ejecting apparatus according to claim 1 , wherein a drive voltage for the plurality of pumps is lower than 42.4 V.
  8. 8 . A liquid ejection head comprising: an ejection unit capable of ejecting liquid; and a circulation unit comprising: a flow path fluidly connected to the ejection unit to supply liquid to the ejection unit; a flow path configured to collect liquid that has not been ejected from the ejection unit; and a plurality of pumps configured to transfer liquid.
  9. 9 . The liquid ejection head according to claim 8 , wherein the pump pumps liquid by displacing a volume of a pump chamber using a piezoelectric element or a solenoid.
  10. 10 . The liquid ejection head according to claim 8 , wherein the plurality of pumps are connected in parallel to the flow path.
  11. 11 . The liquid ejection head according to claim 8 , wherein the plurality of pumps are connected in series to the flow path.
  12. 12 . The liquid ejection head according to claim 8 , wherein a portion of the plurality of pumps are connected in parallel to the flow path and a remaining portion of the plurality of pumps are connected in series to the flow path.
  13. 13 . The liquid ejection head according to claim 8 , wherein the plurality of pumps have a same configuration.
  14. 14 . The liquid ejection head according to claim 8 , wherein the plurality of pumps are driven in response to a same drive signal.
  15. 15 . The liquid ejection head according to claim 8 , wherein a drive voltage for the plurality of pumps is lower than 42.4 V.
  16. 16 . The liquid ejection head according to claim 8 , wherein the liquid ejection head is capable of ejecting a plurality of types of liquids and is provided with the ejection unit and the circulation unit for at least one type of liquid.
  17. 17 . The liquid ejection head according to claim 8 , wherein the circulation unit is provided with a plurality of the ejection units.
  18. 18 . The liquid ejection head according to claim 8 , wherein the circulation unit comprises: a first pressure adjustment mechanism configured to adjust pressure on liquid to be supplied to the ejection unit to a relatively high pressure; and a second pressure adjustment mechanism configured to adjust pressure on liquid collected from the ejection unit to a relatively low pressure.
  19. 19 . The liquid ejection head according to claim 18 , wherein the circulation unit comprises: a first unit comprising the first pressure adjustment mechanism and the pumps; and a second unit comprising the second pressure adjustment mechanism and the pumps, and a plurality of the second units are provided for the first unit.
  20. 20 . A liquid ejecting apparatus comprising: a conveyance unit configured to convey a medium; and a liquid ejection head comprising: an ejection unit capable of ejecting liquid; and a circulation unit comprising a flow path fluidly connected to the ejection unit to supply liquid to the ejection unit, a flow path configured to collect liquid that has not been ejected from the ejection unit, and a plurality of pumps configured to transfer liquid, wherein the liquid ejection head ejects ink onto a medium conveyed by the conveyance unit while moving in a direction intersecting a conveyance direction in which the medium is conveyed by the conveyance unit.

Description

BACKGROUND Field of the Technology The present disclosure relates to a liquid ejecting apparatus and a liquid ejection head. Description of the Related Art Japanese Patent Laid-Open No. 2018-030350 discloses a printing apparatus provided with a drive circuit that drives a pump for circulating ink based on an output from a pressure sensor in a circulation path for circulating ink between two storage portions capable of storing ink and an inkjet head. However, in the printing apparatus disclosed in Japanese Patent Laid-Open No. 2018-030350, a pump drive voltage is initially set at 200 V and is modulated over a range from 120 V to 300 V, and a high drive voltage must be applied to the pump for circulating ink. Thus, in the printing apparatus of Japanese Patent Laid-Open No. 2018-030350, it is necessary to add constituents and functions for suppressing the effects of high voltage, which results in an increase in the size and cost of the apparatus. SUMMARY The present disclosure is made in view of the above problem and provides a technique capable of circulating liquid while suppressing a pump drive voltage. A liquid ejecting apparatus according to some embodiments includes a liquid ejection head comprising an ejection unit capable of ejecting liquid and a circulation path configured to supply liquid to the ejection unit and to collect liquid that has not been ejected from the ejection unit, wherein the circulation path includes a plurality of pumps configured to pump liquid by displacing a volume of a pump chamber using a piezoelectric element or a solenoid. Features of the present disclosure will become apparent from the following description of embodiments with reference to the attached drawings. The following description of embodiments is described by way of example BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are schematic configuration diagrams of a printing mechanism. FIG. 2 is an exploded perspective view of a print head. FIG. 3 is a schematic configuration diagram of a circulation unit. FIG. 4 is a schematic configuration diagram of a circulation path in a first embodiment. FIG. 5 is a schematic configuration diagram of a drive mechanism of a circulation pump. FIG. 6 is a schematic configuration diagram of the circulation path in a comparative example. FIG. 7 is a diagram showing pump performance in Example 1 and the comparative example. FIG. 8 is a schematic configuration diagram of the circulation path in a second embodiment. FIG. 9 is a diagram showing pump performance in Example 2 and the comparative example. FIG. 10 is a schematic configuration diagram of the circulation unit in a third embodiment. FIG. 11 is a schematic configuration diagram of the circulation path in the third embodiment. FIG. 12 is a schematic configuration diagram of the circulation path in a fourth embodiment. FIG. 13 is a schematic configuration diagram of the circulation path in a fifth embodiment. FIG. 14 is a schematic configuration diagram of the circulation unit in a sixth embodiment. FIG. 15 is a schematic configuration diagram of the circulation path in the sixth embodiment. DESCRIPTION OF THE EMBODIMENTS Hereinafter, an example of embodiments of a liquid ejecting apparatus and a liquid ejection head will be described in detail with reference to the accompanying drawings. Incidentally, the following embodiments do not limit the present disclosure, and not all of combinations of features described in the present embodiments are necessarily essential to a solution to the problem to be solved by the present disclosure. Further, the positions, shapes, and the like of constituents described in the embodiments are merely examples and are not intended to limit the present disclosure only thereto. First Embodiment First, a liquid ejecting apparatus according to a first embodiment will be described in detail with reference to FIGS. 1A to 7. In the present embodiment, a so-called serial scan type printing apparatus in which while a print head that ejects ink as liquid is moved in the width direction of a print medium, ink is ejected from the print head onto the print medium to perform printing will be described as an example of a liquid ejecting apparatus. Configuration of Printing Apparatus FIGS. 1A and 1B are schematic configuration diagrams of the printing apparatus. FIG. 1A is a perspective view and FIG. 1B is a block diagram showing a configuration of a control system. A printing apparatus 10 according to the present embodiment includes a conveying portion 12 that conveys a print medium (hereinafter also referred to as “medium”) M and a printing portion 14 that ejects ink onto the print medium M conveyed by the conveying portion 12 to perform printing (see FIG. 1A). The conveying portion 12 includes two conveying roller pairs 16 and 18. The conveying roller pair 16 includes a conveying roller 16a that rotates by a conveying motor 66 (see FIG. 1B) being driven and a driven roller 16b that is driven in pressure contact w