Carriage for ink-jet hard copy apparatus
AssigneeHewlett-Packard Development Company, L.P.
InventorsKumar Balakrishnan, Kenneth R. Williams
Life of this patent
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Abstract
A carriage for an ink-jet printer constrains torsional deflections by providing carriage to writing-instrument latch interface features having a zero clearance interfit such that when opened, the writing-instrument latch allows individual writing-instruments to be accessed and when closed the writing-instrument latch reduces the carriage torsional deflections and increases the torsional stiffness of the carriage by providing a biasing force at each the interface feature.
Claims32
An ink-jet writing instrument carriage assembly for an ink-jet printer having a printing axis, a print media transport axis, and an ink drop firing axis, comprising:
- a carriage;
- a movable pen latch;
- a positioning mechanism associated with the pen latch;
- and
- a positioning mechanism retainer associated with the carriage, wherein the carriage and pen latch are each provided with complementary interfit devices such that when the movable pen latch is in a closed position with the retainer interlocked with the handle, the carriage and latch are held by the interfit devices with zero clearance interfit in at least one the axis such that torsional deflections of the carriage are thereby reduced.
An ink-jet writing instrument carriage assembly, comprising:
- carriage means for mounting at least one ink-jet printhead and for scanning across print medium positioned adjacently thereto such that the printhead is positioned with an ink drop nozzle side aligned for depositing ink drops on the print medium and a holddown side aligned for receiving a latching force;
- movable pen latch means for accessing the printhead mounted in the carriage means when the latch means is in an open position and for providing a force against a holddown side of the printhead when in a closed position;
- fixedly mounted to the carriage means, latch retainer means for receiving the pen latch means via complementary interfit devices of each;
- associated with the pen latch means, latch securing means for securing the pen latch means against the carriage means and forcing a interfit between the complementary interfit device;
- and
- mounted on the carriage means, bias means for holding the latch securing means in the closed position,
- wherein the carriage means and pen latch means complementary interfit devices provide pen pitch, pen roll and pen yaw counterforces when the pen latch means is in the closed position.
A method for reducing torsional deflections in an ink-jet writing-instrument carriage, comprising the steps of:
- providing the carriage and writing-instrument latch with geometrically configured complementary interfit surfaces;
- and
- positioning the writing-instrument latch on the carriage against a bias such that when the writing-instrument latch is closed, counterforces to carriage torsional deflections which would affect the printhead-to-paper orientation and distance are established by the complementary interfit surfaces.
An ink-jet hard copy apparatus having a plurality of ink-jet writing-instruments for ejecting droplets of ink in a printing zone of the apparatus, the apparatus being defined by a scanning axis, a print media transport axis, and an ink drop firing axis, wherein the axes are mutually orthogonal, comprising:
- a writing-instrument carriage, mounted in the apparatus for selectively scanning the printing zone along parallel to the scanning axis, the carriage including a plurality of bays for locating the writing-instruments with respect to the printing zone;
- a movable writing-instrument latch having an open position for accessing the bays and a closed position for securing the writing-instruments in the bays;
- a writing-instrument latch handle associated with the writing-instrument latch;
- and
- a biased handle retainer for the carriage,
- wherein the carriage and writing-instrument latch are each provided with complementary interfit devices such that when the movable writing-instrument latch is in the closed position with the retainer interlocked with the handle, the carriage and latch are held by the interfit devices with zero clearance interfit in at least one the axis such that torsional deflections of the carriage are thereby reduced.
Dependencies are inferred from the claim text.