Printer fluid circulation system including an air isolation chamber and a printer fluid pressure control valve

Patent metadata

Field	Value
Publication number	US-10226940-B2
Application number	US-201415504013-A
Country	US
Kind code	B2
Filing date	Aug 14, 2014
Priority date	Aug 14, 2014
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

Systems and related methods are described for circulating and printing fluid onto a printer media. In one example, a system can include an air isolation chamber to pool printing fluid circulated within the system. The air isolation chamber can be fluidly connected to a printhead assembly to eject a portion of the printing fluid onto the printer media. The system can further include a pump to pump printing fluid from the air isolation chamber to the printhead assembly. The system can further include a pressure control valve along a return line between the air isolation chamber and the printhead assembly to regulate the flow of unejected printing fluid to the air isolation chamber to control printing fluid pressure over the printhead assembly.

First claim

What is claimed is:

1. A system comprising:
an air isolation chamber to pool and remove air bubbles within printing fluid to be circulated within the system;
a printhead assembly to print a portion of the printing fluid onto a printer media;
a supply line to supply printing fluid from the air isolation chamber to the printhead assembly;
a pump along the supply line to pump printing fluid from the air isolation chamber to the printhead assembly;
a return line to return unprinted printing fluid from the printhead assembly to the air isolation chamber; and
a pressure control valve along the return line to regulate the return flow of unprinted printing fluid to the air isolation chamber to control printing fluid pressure over the printhead assembly, wherein the pressure control valve is a seated ball valve including a spring such that, during printing, the seated ball valve is to compress the spring to open a path to the air isolation chamber responsive to pressure within the return line above or equal to a predetermined value, and further such that, during printing and responsive to pressure within the return line less than the predetermined value, the seated ball valve is to seat against a common wall of the pressure control valve and the air isolation chamber to block the flow of the unprinted print fluid to the air isolation chamber.

2. The system of claim 1 , wherein the printhead assembly includes:
a printhead including a nozzle to eject printing fluid towards the printer media; and
a manifold that includes an inlet to receive printing fluid from the supply line, a return outlet to return unejected printing fluid to the return line, and a channel to divert a portion of the printing fluid to the printhead.

3. The system of claim 2 ,
wherein the printhead assembly includes multiple printheads, and
wherein the manifold includes multiple channels to divert printing fluid from the manifold to a corresponding printhead.

4. The system of claim 1 ,
wherein the printhead assembly is moved relative to the air isolation chamber during printing.

5. The system of claim 4 ,
wherein the supply line and return line are in the form of flexible tubing that moves with the printhead assembly during printing.

6. The system of claim 1 , wherein the pump is to pump printing fluid from the air isolation chamber to the printhead assembly by deforming the supply line.

7. The system of claim 1 , wherein the pump is in the form of a diaphragm pump that connects a first segment of the supply line to a second segment of the supply line.

8. The system of claim 1 , wherein the spring is biased to close the path to the air isolation chamber when the pressure within the return line is below the predetermined value.

9. The system of claim 1 , wherein the pressure control valve connects a first segment of the return line to a second segment of the return line.

10. The system of claim 1 , wherein the pressure control valve is positioned at the air isolation chamber and connects an end of the return line to the air isolation chamber.

11. A method comprising:
fluidly connecting an air isolation chamber to a printhead assembly in a printing fluid circulation and printing system so as to circulate printing fluid between the air isolation chamber and the printhead assembly, the air isolation chamber to pool and remove air bubbles within the printing fluid and the printhead assembly to print a portion of printing fluid onto a printer media during printing;
installing a pump between the air isolation chamber and the printhead assembly to pump printing fluid from the air isolation chamber to the printhead assembly; and
installing a pressure control valve between the printhead assembly and the air isolation chamber to regulate the return flow of unprinted printing fluid to the air isolation chamber to control printing fluid pressure over the printhead assembly, wherein the pressure control valve is a seated ball valve including a spring such that, during printing, the seated ball valve compresses the spring to open a path to the air isolation chamber responsive to pressure within the return line above or equal to a predetermined value, and further such that, during printing and responsive to pressure within the return line less than the predetermined value, the seated ball valve seats against a common wall of the pressure control valve and the air isolation chamber to block the flow of the unprinted print fluid to the air isolation chamber and produce a positive pressure in the printhead assembly.

12. The method of claim 11 , wherein fluidly connecting the air isolation chamber to a printhead assembly includes:
fluidly connecting a first end of the supply line to an outlet of the air isolation chamber;
fluidly connecting a second end of the supply line to an inlet of the printhead assembly;
fluidly connecting a first end of the return line to an outlet of the printhead assembly; and
fluidly connecting a second end of the return line to an inlet of the air isolation chamber.

13. A printer comprising:
a printing fluid reservoir to hold a printing fluid supply;
an air isolation chamber in fluid connection with the printing fluid reservoir to receive printing fluid from the printing fluid reservoir, the air isolation chamber to be partially filled with printing fluid so as to pool printing fluid and provide an air pocket to remove air bubbles from the printing fluid;
a printhead assembly in fluid communication with the air isolation chamber to circulate printing fluid between the air isolation chamber and the printhead assembly and to print a portion of the circulated printing fluid onto a printer media;
a supply line to supply printing fluid from the air isolation chamber to the printhead assembly;
a pump along the supply line to pump printing fluid from the air isolation chamber to the printhead assembly;
a return line to return unprinted printing fluid from the printhead assembly to the air isolation chamber; and
a pressure control valve connected to the return line to regulate the flow of unprinted printing fluid to the air isolation chamber to control printing fluid pressure over the printhead assembly, wherein the pressure control valve is a seated ball valve including a spring such that, during printing, the seated ball valve is to compress the spring to open a path to the air isolation chamber responsive to pressure within the return line above or equal to a predetermined value, and further such that, during printing and responsive to pressure within the return line less than the predetermined value, the seated ball valve is to set against a common wall of the pressure control valve and the air isolation chamber to block the flow of the unprinted print fluid to the air isolation chamber and to build the printing fluid pressure over the printhead assembly.

14. The printer of claim 13 , wherein the pump is to run at a speed that is independent of the real-time pressure within the supply line.

Assignees

• Hewlett Packard Development Co

Inventors

• Olsen David
• Devries Mark A

Classifications

• B41J2/18

  Ink recirculation systems · CPC title

• B41J2/19 Primary

  for removing air bubbles · CPC title

• B41J2/17596

  Ink pumps, ink valves · CPC title

• B41J2202/12

  with ink circulating through the whole print head · CPC title

• B41J2/175 Primary

  Ink supply systems {; Circuit parts therefor} · CPC title