Volumetrically efficient printer ink supply combining foam and free ink storage
AssigneeHewlett-Packard Company
InventorJeffrey K. Pew
Life of this patent
Estimating the term…
Abstract
An ink supply is contained in a manner that combines foam and free ink storage to provide high volumetric efficiency, back pressure regulation to protect against ink leakage, and a generally lower cost, easy-to-manufacture assembly. Ink leakage protection is present despite exposure of the supply to substantial variations in temperature and ambient air pressure. The container is divided, and part of the container includes porous material for storing ink. Capillary pressures of the material and of a bubble generator in the free-ink part of the container are selected to control the sequence with which ink is removed from the container parts.
Claims18
An ink container comprising:
- a reservoir that is divided into a free-ink volume and a capillary volume, each volume configured for storing ink;
- an outlet formed in the reservoir to enable ink to flow out of the capillary volume;
- porous wicking material having a first capillary pressure and located inside the capillary volume adjacent to the outlet;
- accumulator material located in the capillary volume and being absorbent for storing ink therein, the accumulator material contacting the wicking material and having a second capillary pressure;
- the wicking material being in fluid communication with the free-ink volume;
- and
- a bubble generator having a capillary pressure that is less than the first capillary pressure but greater than the second capillary pressure, the bubble generator being located to connect the free-ink volume with ambient air.
A method of sizing an ink supply reservoir for a printer, comprising the steps of:
- providing a three-dimensional reservoir for storing ink such that the reservoir is divided into a free-ink volume and into a capillary volume;
- establishing two of the three dimensions for the free-ink volume and the capillary volume, one of those established dimensions being height, wherein ink is stored in the free-ink volume at any height within a range of ink heights in the free-ink volume, and wherein ink-absorbent accumulator material is located in the capillary volume;
- and
- determining the third dimension of the capillary volume as a function of two different ink heights in the range of ink heights.
A method of storing ink in a container for delivery therefrom through an outlet, the method comprising the steps of:
- storing a portion of the ink in a first part of the container that defines a volume that is sealed from ambient but for an opening that has a first capillary pressure;
- storing the remaining portion of the ink in a second part of the container that defines a volume that is part filled with porous accumulator material that has a second capillary pressure that is substantially lower than the first capillary pressure;
- and
- locating porous wicking material having a third capillary pressure in the container in contact with the accumulator material and in fluid communication with the first part of the container and with the outlet.
Dependencies are inferred from the claim text.