Hewlett-Packard Company

Jeffrey A Thoman

David W Swanson

W Wistar Rhoads

Mindy A Hamlin

Robert R Beeson

Jaren D Marler

Brian D Gragg

James G Salter

Corrina A Hall

An ink jet printer includes a movable carriage supported above an ink-receiving medium by a rail defining a carriage axis, with a cartridge holder mounted on said carriage having a plurality of cartridge compartments each receiving a respective thermal ink jet printer cartridge. Each cartridge is provided with three datum surfaces located on the perimeter of a sidewall of the cartridge, and sufficiently spaced apart from each other and from the center of gravity of the cartridge to provide accurate and stable alignment. More particularly, the nozzle plate of the cartridge is attached to a lower surface of snout portion such that the Y axis of the nozzle plate is substantially parallel to the first sidewall, with the first and second datum surfaces at the front and rear of a lower end of the ink reservoir portion straddling the snout and the third datum surface at an upper end of the ink reservoir portion. At least the first and second datum surfaces are spaced from the Y axis within a predetermined tolerance by a first predetermined spacing. The cartridge is also provided with a forwardly facing fourth datum surface on a lower end of the ink reservoir portion in front of the snout portion, and with a downwardly facing fifth datum surface on the perimeter wall of the ink reservoir portion adjacent the fourth datum surface and above said snout portion, so as to establish a pivot axis above and in front of the snout, and with a rearwardly facing sixth datum surface on an upper end of the ink reservoir portion of said perimeter wall. The fourth datum surface is spaced from the X axis of the nozzle plate within a predetermined tolerance, while the locations of the fifth datum surface (which is used to determine the spacing of the nozzle to the print medium) and the sixth datum surfaces (which is used to determine angular orientation of the cartridge about the pivot point) are somewhat less critical.

Side biased datum scheme for inkjet cartridge and carriage

Precise alignment between two or more nozzle plates affixed to print cartridges installed in a single carriage of an ink printer is achieved by machining datum projections on each print cartridge after its nozzle plate has been permanently secured to the print cartridge. The machined datum projections on the print cartridge contact surfaces on the carriage when the print cartridge is installed in the carriage such that the dimensions of the datums affect the position of the cartridge, and hence the nozzle plate, within the carriage.

Alignment of multiple nozzle members in a printer

In a printer carriage adapted for holding multiple pen cartridges in separate compartments, each carriage compartment includes one or more key-coded barriers at an entrance to the compartment to provide a first level carriage lockout scheme against non-matching cartridge tabs. A second level carriage lockout is provided to differentiate between different families of print cartridges which successfully pass through the first level lockout, which second level is based on predetermined barrier floor configurations in the bottom of each carriage compartment which block non-matching wings on particular print cartridge families.

Method and device for preventing unintended use of print cartridges

Datum formation for improved alignment of multiple nozzle members in a

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San Diego, CA, United States of America

Jeffrey A Thoman