Method and controller to prevent ink leakage from a print head
AssigneeCanon Production Printing Holding B.V.
InventorsKay Luecke, Admir Lela
Life of this patent
Estimating the term…
Abstract
The negative pressure in the ink chamber of a nozzle of a print head is reduced in a printing interruption phase, in particular upon transport of the print head from a cleaning position into a printing position, relative to the negative pressure in a printing phase. The leaking of ink during the printing interruption phase may thus be reliably avoided, and the print quality may be increased.
Claims16
A method for preventing the leaking of ink from a print head of an inkjet printing device, the print head including a nozzle plate and at least one nozzle, the method comprising:
- determining presence of a printing interruption phase of the print head or that a previous print preparation phase has been performed;
- reducing, based on the determination, a physical rest pressure of the ink in the nozzle to a printing interruption level that is lower than a printing operation level used as a rest pressure during a printing phase of the print head;
- determining state information corresponding to a degree of degradation of a protective layer disposed on the nozzle plate of the print head;
- and
- adapting the printing interruption level based on the state information.
A pressure controlling apparatus for an inkjet printing device, comprising:
- an output;
- and
- a controller that is configured to:
- determine a presence of a printing interruption phase of a print head of the inkjet printing device or that a previous print preparation phase has been performed;
- generate a control signal, based on the determination, to induce a reduction of a physical rest pressure of ink in a nozzle of the print head to a printing interruption level that is lower than a printing operation level which is used as a rest pressure during a printing phase of the print head;
- determine state information corresponding to a degree of degradation of a protective layer disposed on a nozzle plate of the print head;
- adapt the printing interruption level based on the determined state information;
- and
- provide the generated control signal to the output.
An inkjet printing device, comprising:
- a print head having at least one nozzle that is configured to eject ink droplets onto a recording medium in a printing phase to print a print image onto the recording medium;
- a negative pressure tank that stores ink and that is connected with the print head via an ink channel to provide ink for printing of a print image;
- a pressure adjuster configured to vary a physical pressure in the negative pressure tank to vary a physical rest pressure of ink in the nozzle;
- and
- a controller that is configured to:
- determine a presence of a printing interruption phase of a print head of the inkjet printing device or that a previous print preparation phase has been performed;
- determine state information corresponding to a degree of degradation of a protective layer disposed on a nozzle plate of the print head;
- adapt the printing interruption level based on the state information;
- and
- induce the pressure adjuster, based on the determination of the presence of the printing interruption phase or that the previous print preparation phase has been performed, to vary the physical rest pressure of the ink in the nozzle.
Dependencies are inferred from the claim text.