Slow scan stitching mechanism
AssigneeXerox Corporation
InventorsFrederick A. Donahue, Paul J. Rowe
Life of this patent
Estimating the term…
Abstract
A translatable information transfer device, such as ink jet printhead, is stepwise advanced by a mechanism consisting of a lead screw axially spring biased at one end, cam surface provided at the other end of the lead screw, fixed cam follower which engages the cam surface, and a carrier for the information transfer device mounted on the lead screw with cooperating internal threads. Rotation of the lead screw does not advance the carrier having the information transfer device until after one complete revolution of the lead screw, whereupon the cam surface and cam follower permit the information transfer device to axially advance a predetermined distance, such as, for example, one printing swath.
Claims15
A slow scan stitching mechanism for an information transfer device, comprising:
- a rotatably mounted lead screw having a thread, an axis, and opposing ends, the lead screw being axially resiliently biassed in a first of said opposing ends and being rotatably driven about the lead screw axis;
- a head carrier having an information transfer head and an internal thread, the head carrier being mounted on the lead screw with the head carrier internal thread and lead screw thread being cooperatively engaged;
- a cam being fixedly provided at another end of said opposite ends of the lead screw, the cam having a cam surface substantially perpendicular to the lead screw axis, the cam surface having a step with a predetermined step length;
- p1 a fixed cam follower engaging the cam surface, the cam surface being urged against the cam follower by the resilient biasing of the lead screw in said first direction;
- and
- the lead screw thread and the cam surface being shaped such that the information transfer head is maintained in a fixed location when the lead screw and cam are rotated for substantially one revolution and then are advanced in said first direction by the resilient biasing of the lead screw when the cam follower reaches the cam surface step, said advance in the first direction being equal to the predetermined step length, so that the information transfer head is advanced by said cam surface step substantially instantaneously during each complete revolution of the lead screw.
A slow scan stitching mechanism for an information transfer device, comprising:
- a lead screw having an external thread between two opposing ends and an axis, the lead screw being rotatably driven about the lead screw axis in at least two fixed bearings located adjacent the lead screw ends, each of said bearings slidingly surrounding a portion of the lead screw without an external thread, thereby allowing axial slip of the lead screw therein;
- a disc shaped cam having an axis and a cam surface, the cam being coaxially attached to one of said end of the lead screw for rotation therewith, the cam surface being substantially perpendicular to the lead screw axis and having a step thereon with a predetermined step length;
- a fixed cam follower;
- means for axially urging another end of said opposing ends of the lead screw in a direction towards the cam, so that the cam surface is continually urged against the cam follower;
- a head carrier having an internal thread and an information transfer head, said head carrier being mounted on the lead screw with the head carrier thread and lead screw thread cooperatively engaged;
- and
- the lead screw thread and the cam surface being shaped such that the information transfer head is maintained in a stationary position when the lead screw and cam are rotated for substantially one revolution and then is advanced along the axis of the lead screw in the direction of the urging by said urging means by the same distance as said length of the cam surface step, when the cam surface is rotated so that the cam follower reaches the cam surface step, the cam and cam follower slidably displacing the lead screw in an axial direction through the bearings opposite the urging direction of said urging means until the cam follower reaches the cam surface step, whereat the means for urging the lead screw advances the information transfer head axially for a distance equal to the length of the cam surface step.
Dependencies are inferred from the claim text.