High speed electrostatic printer

Claim 2

A high speed image producing device comprising: a plurality of different functional stations, including an image forming station and an image utilization station; an image transfer drum having a central axis; drum carrier means for continuously moving said central axis in a closed pAth past at least a first one of said different functional stations being mounted in apparent rolling contact with said drum; and drum drive means for continuously rotating said drum about said central axis at a rate which causes the surface of said drum to be in apparent rolling contact with a line outside of and parallel with said closed path as said drum carrier means moves said central axis in said closed path, said drum carrier means and said drum drive means together causing an image formed at a point of a surface of said drum to move sequentially past all of said different functional stations, said drum drive and carrier means further causing said image to move past at least two of said different functional stations for each transit of said carrier means in said closed path, whereby said image produced by said image forming station is carried along a roulette having a cusp adjacent to said first of said different functional stations.

Claim 3

The device of claim 1 wherein a second one of said different functional stations is mounted adjacent to and in fixed spaced relation to said drum whereby said second station performs its function on the surface of said drum while a point on the drum is between cusps of said roulette.

Claim 4

The device of claim 1 wherein the line in which said drum is in apparent rolling contact is a nonintegral multiple of the circumference of said drum whereby the entire surface of said drum will be utilized.

Claim 5

A high speed electrostatic image producing device of the type utilizing a plurality of functional stations, including a latent image forming station, a development station, and an image utilization station, and also utilizing an image carrying photoconductive insulating surface, the improvement comprising: an image transfer drum having a central axis, said drum having the photoconductive insulating surface mounted thereon; drum carrier means for moving said central axis of said drum in a path past at least one of the functional stations, said functional station being in apparent rolling contact with said drum; and drum drive means for continuously rotating said drum about said central axis at a rate causing the surface of said drum to be in an apparent rolling contact with a line parallel to and outside of said closed path as said drum carrier means moves said central axis, said drum carrier means and said drum drive means together causing an image formed at a point on the surface of said drum to move sequentially from the latent image forming station to the development station and then to the image utilization station along a path in which the point on the surface of said drum approaches at least said one of the functional stations with a diminishing velocity, having a minimum velocity at a point adjacent to that functional station, said drum drive and carrier means further causing said image to move past at least two of the functional stations for each transit of said carrier means in said closed path.

Claim 6

A high speed electrostatic image producing device of the type utilizing a plurality of functional stations, including a latent image forming station, a development station, and an image utilization station, and also utilizing an image carrying photoconductive insulating surface, the improvement comprising: an image transfer drum having a central axis, said drum having the photoconductive insulating surface mounted thereon; drum carrier means for moving said central axis of said drum in a path past at least one of the functional stations, said functional station being in apparent rolling contact with said drum; and drum drive means for continuously rotating said drum about said central axis at a rate causing the surface of said drum to be in an apparent rolling contact with a line parallel to and outside of said closed path as said drum carrier means moves said central axis, said drum carrier means and said drum drive means together causing an image formed at a point on the surface of said drum to move sequentially from the latent image forming station to the development station and then to the image utilization station along a path in which the point on the surface of said drum approaches at least said one of the functional stations with a diminishing velocity, having a minimum velocity at a point adjacent to that functional station, said drum drive and carrier means further causing said image to move past at least two of the functional stations for each transit of said carrier means in said closed path.

Claim 7

A high speed electrostatic image producing device, comprising: a support member; a plurality of functional stations, at least some of which are mounted along the arc of a circle in fixed spaced relation to said support member, said functional stations comprising: a latent image forming station, a development station, and an image utilization station; an image transfer drum for transferring images produced at said image forming station to said image utilization station, said drum having a central axis and being rotatable thereabout, said drum being movably mounted over said support member and lying inside the arc on which said functional stations are mounted, and said drum being constrained to roll along a closed path having a length greater than the circumference of said drum; and drive assembly means for moving a point on the surface of said drum sequentially to said functional station, said drive assembly means comprising: constraining means tangent to said drum and constraining said drum to rOtate about said central axis when said central axis is translated; drum carrier means for supporting said drum and for translating said central axis of said drum through a closed path parallel to said constraining means substantially throughout its length, said drum carrier means carrying said drum past at least two of said functional stations for each transit of said carrier means; and drive means for moving said carrier means, said drive means, said carrier means and said constraining means together causing a point on a surface of said drum to describe a roulette having nodes at least some of which are adjacent to some of said functional stations, whereby an image produced on a surface of said drum at said image forming station will move along the roulette to said developing station and then to said image utilization station.

Claim 8

A high speed electrostatic image producing device, comprising: a support member; a plurality of functional stations, at least some of which are mounted along the arc of a circle in fixed spaced relation to said support member, said functional stations comprising: a latent image forming station, a development station, and an image utilization station; an image transfer drum for transferring images produced at said image forming station to said image utilization station, said drum having a central axis and being rotatable thereabout, said drum being movably mounted over said support member and lying inside the arc on which said functional stations are mounted, and said drum being constrained to roll along a closed path having a length greater than the circumference of said drum; and drive assembly means for moving a point on the surface of said drum sequentially to said functional station, said drive assembly means comprising: constraining means tangent to said drum and constraining said drum to rOtate about said central axis when said central axis is translated; drum carrier means for supporting said drum and for translating said central axis of said drum through a closed path parallel to said constraining means substantially throughout its length, said drum carrier means carrying said drum past at least two of said functional stations for each transit of said carrier means; and drive means for moving said carrier means, said drive means, said carrier means and said constraining means together causing a point on a surface of said drum to describe a roulette having nodes at least some of which are adjacent to some of said functional stations, whereby an image produced on a surface of said drum at said image forming station will move along the roulette to said developing station and then to said image utilization station.

Claim 9

The device of claim 5 wherein said constraining means has the form of the arc of a circle, whereby the closed path upon which said drum rolls will be a circle.

Claim 10

A high speed electrostatic printing device comprising: a support member; a plurality of functional stations, said functional stations comprising: a charging station, a latent image forming station, a development station, a printing station, and a cleaning station; said charging station; said development station and said printing station being mounted in fixed spaced space relation on said support member; a photoconductive insulating surfaced image transfer drum for transferring images produced at said image forming station to said printing station, said drum having a central axis and being rotatable thereabout, and said drum being mounted for planetary movement about a point on said support member; support means for supporting said latent image forming station and said cleaning station, said support means being attached to said central axis of said drum and being movable therewith, said support means maintaining said latent image forming station and said cleaning station in fixed spaced relation to said central axis of said drum; and planetary drive means for imparting motion to said drum, including: drum carrier means for moving said drum past said charging station, said development station and said printing station; and drum rotating means for rotating said drum about said central axis as said carrier means moves said drum, said drum rotating means and said drum carrier means causing a point on the surface of said drum to move along a path having cusps located adjacent to said charging, development sand printing stations, whereby an image produced on the surface of said drum will move intermittently along the path from said latent image forming station to said printing station.

Claim 11

A high speed electrostatic printing device comprising: a support member; a plurality of functional stations, said functional stations comprising: a charging station, a latent image forming station, a development station, a printing station, and a cleaning station; said charging station; said development station and said printing station being mounted in fixed spaced space relation on said support member; a photoconductive insulating surfaced image transfer drum for transferring images produced at said image forming station to said printing station, said drum having a central axis and being rotatable thereabout, and said drum being mounted for planetary movement about a point on said support member; support means for supporting said latent image forming station and said cleaning station, said support means being attached to said central axis of said drum and being movable therewith, said support means maintaining said latent image forming station and said cleaning station in fixed spaced relation to said central axis of said drum; and planetary drive means for imparting motion to said drum, including: drum carrier means for moving said drum past said charging station, said development station and said printing station; and drum rotating means for rotating said drum about said central axis as said carrier means moves said drum, said drum rotating means and said drum carrier means causing a point on the surface of said drum to move along a path having cusps located adjacent to said charging, development sand printing stations, whereby an image produced on the surface of said drum will move intermittently along the path from said latent image forming station to said printing station.

Claim 12

A high speed electrostatic printer comprising: a plurality of functional stations, including: a charging station, a stationary latent image forming station, a development station, a printing station, and a cleaning station; an image transfer drum having a photoconductive insulating surface mounted thereon, said drum having a central axis and being rotatable thereabout; a drum carrier having said drum rotatably mounted thereon, said carrier also having said charging, development, cleaning and printing stations mounted thereon in fixed space relation to said drum; drum carrier drive means for moving said carrier in a closed path, a portion of said closed path being adjacent to said stationary latent image forming station; and drum rotating means for causing said drum to rotate about said central axis in apparent rolling contact with a line parallel to and outside of said closed path as said drum carrier means moves said carrier through said closed path to cause a point on a surface of said drum to describe a curve having a plurality of cusps, at least one of which is adjacent to said latent image forming station, and a second of which is adjacent to said printing station, whereby an image produced at said stationary latent Image forming station will be carried along the curve to said printing station.

Claim 13

A high speed electrostatic printer comprising: a plurality of functional stations, including: a charging station, a stationary latent image forming station, a development station, a printing station, and a cleaning station; an image transfer drum having a photoconductive insulating surface mounted thereon, said drum having a central axis and being rotatable thereabout; a drum carrier having said drum rotatably mounted thereon, said carrier also having said charging, development, cleaning and printing stations mounted thereon in fixed space relation to said drum; drum carrier drive means for moving said carrier in a closed path, a portion of said closed path being adjacent to said stationary latent image forming station; and drum rotating means for causing said drum to rotate about said central axis in apparent rolling contact with a line parallel to and outside of said closed path as said drum carrier means moves said carrier through said closed path to cause a point on a surface of said drum to describe a curve having a plurality of cusps, at least one of which is adjacent to said latent image forming station, and a second of which is adjacent to said printing station, whereby an image produced at said stationary latent Image forming station will be carried along the curve to said printing station.

Claim 14

A high speed electrostatic printing device comprising: a plurality of functional stations including: a latent image forming station, a development station, and a stationary printing station; a plurality of image transfer drums each having a photoconductive insulating surface thereon; drum carrier means for supporting said drums and for presenting each of said drums sequentially to said latent image forming station and said development station; carrier support means for moving said carrier means past said stationary printing station, said carrier support means having mounted thereon said latent image forming station and said development station; and drum rotating means for continuously rotating said drums about their central axes at rate which causes the surface of said drums to be in apparent rolling contact with said printing station as said drum carrier means presents said drums to said functional stations, said drum rotating means and said drum carrier means together causing said drums to be sequentially in rolling contact with said printing station and also causing a point on a surface of each drum to follow a path having a plurality of cusps, at least one of which is adjacent to said latent image forming station and second of which is adjacent to said printing station, whereby a point on a surface of each of said image transfer drums will move along the path from station to station having a minimum velocity at said cusps adjacent to said image forming station and said printing station.

Claim 15

A high speed electrostatic printing device comprising: a plurality of functional stations including: a latent image forming station, a development station, and a stationary printing station; a plurality of image transfer drums each having a photoconductive insulating surface thereon; drum carrier means for supporting said drums and for presenting each of said drums sequentially to said latent image forming station and said development station; carrier support means for moving said carrier means past said stationary printing station, said carrier support means having mounted thereon said latent image forming station and said development station; and drum rotating means for continuously rotating said drums about their central axes at rate which causes the surface of said drums to be in apparent rolling contact with said printing station as said drum carrier means presents said drums to said functional stations, said drum rotating means and said drum carrier means together causing said drums to be sequentially in rolling contact with said printing station and also causing a point on a surface of each drum to follow a path having a plurality of cusps, at least one of which is adjacent to said latent image forming station and second of which is adjacent to said printing station, whereby a point on a surface of each of said image transfer drums will move along the path from station to station having a minimum velocity at said cusps adjacent to said image forming station and said printing station.