Wet capping system for inkjet printheads
AssigneeHewlett-Packard Company
InventorThomas J. Purwins
Life of this patent
Estimating the term…
Abstract
A wet capping system is provided for inkjet printheads used in various inkjet printing mechanisms, such as printers, facsimile machines, scanners, plotters and the like. A wicking cap has an elastomeric body with an ink wicking area surrounded by a sealing lip to seal a region of the pen face surrounding the printhead nozzles. Optionally, the wicking area is lined with an elastomer or a compliant thin film, such as a sheet of mylar film, to define a wicking surface. The wicking surface draws ink from the pen through capillary action. While the pen is capped, the extracted ink dissolves any ink solids or residue accumulated around the nozzles. While useful with conventional dye based inks, this wet capping system is especially useful to remove the tough residue left on a printhead by pigment based inks.
Claims33
A method of servicing an inkjet printhead used in an inkjet printing mechanism, comprising the steps of:
- capping the printhead through relative movement of the printhead and a cap until a capped position is reached where the printhead is sealed against a wicking surface of the cap, with the cap including a non-porous insert of a high surface energy material that defines the wicking surface;
- in the capped position, wicking ink through capillary action from the printhead onto the cap wicking surface;
- in the capped position, dissolving dried ink residue on the printhead using the wicked ink;
- uncapping the printhead after the dissolving step;
- and
- after uncapping, cleaning the wicking surface of the cap to remove therefrom dissolved ink residue by scraping the wicking surface of the cap with a cap scraper of a rigid material.
A service station for servicing an inkjet printhead used in an inkjet printing mechanism, comprising:
- a frame;
- a cap supported by the frame to selectively seal the printhead in a capped position through relative movement of the printhead and cap, the cap having a wicking surface against which the printhead is sealed in the capped position, with the cap including a non-porous insert of a high surface energy material that defines the wicking surface which extracts ink from the printhead through capillary action;
- and
- a scraper of a rigid material supported by the frame to selectively clean the wicking surface through relative movement of the scraper and cap when the printhead is uncapped to remove dissolved ink residue from the wicking surface of the cap.
An inkjet printing mechanism, comprising:
- a chassis;
- a printhead mounted to the chassis for reciprocal movement across a printzone and a service station chamber portion of the chassis;
- and
- a service station within the service station chamber that selectively services the printhead, the service station including:
- a frame supported by the chassis;
- a cap supported by the frame to selectively seal the printhead in a capped position through relative movement of the printhead and cap, with the cap having a wicking surface against which the printhead is sealed in the capped position, and with the cap including a non-porous insert of a high surface energy material that defines the wicking surface which extracts ink from the printhead through capillary action;
- and
- a scraper of a rigid material supported by the frame to selectively clean the wicking surface through relative movement of the scraper and cap when the printhead is uncapped to remove dissolved ink residue from the wicking surface of the can.
A method of sealing an inkjet printhead used in an inkjet printing mechanism, with the printhead having a planar orifice plate defining plural ink-ejecting nozzles and having a nozzle-free region adjacent the plural nozzles, the method comprising the steps of:
- providing the inkjet printing mechanism with a cap engageable with printhead orifice plate, the cap having a wicking surface with a convex contour including a linear apex portion and a sloping portion adjacent to the apex portion;
- through relative movement of the printhead and the cap, contacting the nozzle-free region of the planar orifice plate with the apex portion before contacting the orifice plate with the sloping portion;
- gradually covering the plural nozzles with the sloping portion of the wicking surface while continuing said relative movement until a capped position is reached where the printhead is sealed against the wicking surface of the cap;
- through relative movement of the printhead and the cap, moving the printhead and the cap apart;
- and
- after the moving step, cleaning the wicking surface of the cap to remove therefrom dissolved ink residue by scraping the wicking surface of the cap with a cap scraper of a rigid material.
A method of sealing an inkjet printhead used in an inkjet printing mechanism, with the printhead having an orifice plate defining plural ink-ejecting nozzles and having a nozzle-free region adjacent the plural nozzles, the method comprising the steps of:
- providing the inkjet printing mechanism with a cap engageable with printhead orifice plate, the cap having a wicking surface with a convex contour including a linear apex portion and a sloping portion adjacent to the apex portion, wherein the convex wicking surface comprises a surface defined as a chordal planar cut through a cylinder to define an arcuate cross sectional shape substantially perpendicular to the apex portion;
- through relative movement of the printhead and the cap, contacting the nozzle-free region of the orifice plate with the apex portion before contacting the orifice plate with the sloping portion;
- and
- gradually covering the plural nozzles with the sloping portion of the wicking surface while continuing said relative movement until a capped position is reached where the printhead is sealed against the wicking surface of the cap.
A method of sealing an inkjet printhead used in an inkjet printing mechanism, with the printhead having an orifice plate defining plural ink-ejecting nozzles and having a nozzle-free region adjacent the plural nozzles, wherein the orifice plate also defines first and second lateral nozzle-free regions, with the first lateral nozzle-free region adjacent a first one of said at least two linear arrays of nozzles, and the second lateral nozzle-free region adjacent a second one of said at least two linear arrays of nozzles the method comprising the steps of:
- providing the inkjet printing mechanism with a cap engageable with printhead orifice plate, the cap having a wicking surface with a convex contour including a linear apex portion and a sloping portion adjacent to the apex portion, wherein the wicking surface has first and second sloping portions, with the apex portion being located between the first and second sloping portions;
- through relative movement of the printhead and the cap, contacting the nozzle-free region of the orifice plate with the apex portion before contacting the orifice plate with the sloping portion;
- gradually covering the plural nozzles with the sloping portion of the wicking surface while continuing said relative movement until a capped position is reached where the printhead is sealed against the wicking surface of the cap;
- and
- after said gradually covering step, covering the first and second lateral nozzle-free regions with the respective first and second sloping portions of the wicking surface.
Dependencies are inferred from the claim text.