Method and apparatus for applying toner to an electrostatic image
AssigneeEastman Kodak Company
InventorsArthur S. Kroll, Arthur E. Dunn, Michael L. DeCecca, David M. Gaudino, Jerry E. Livadas, David R. Fairport, James G. Rydelek
Life of this patent
Estimating the term…
Abstract
A series of electrostatic images carried by a drum or similar image member are toned with different colored toners by a movable developing device. The developing device moves a series of developing units to a position aligned with the drum. An applicator is an aligned unit is moved relative to the rest of the unit toward the drum to operatively position the unit for developing each electrostatic image.
Claims37
A developing device for applying toner to an electrostatic image carried on an image member as said electrostatic image moves through a developing position, said developing device comprising a plurality of developing units, each unit including an applicator which applicator includes rotatable means for moving dry particulate developer through the developing position and a housing which housing includes means for supplying such dry particulate developer to said applicator,
- characterized in that each of said units is movable to a position aligned with said developing position, and each of said applicators is movable toward and away from said developing position with respect to said means for supplying.
A developing device for applying color toners to electrostatic images carried by a moving image member as said images move through a single fixed development position, said developing device comprising:
- a plurality of developing units, each unit containing a toner of a color different from the other units, each of said units including an applicator assembly mounted in said unit and movable toward and away from the development position with respect to a portion of said unit, each applicator assembly including a magnetic core and a nonmagnetic shell, at least one of said core and shell being rotatable to move developer having a magnetic component around said shell and through a development position in developing relation with an electrostatic image carried by said image member, and
- means for moving said units as a group through a path that aligns each unit with said developing position, one after another.
A developing device for applying color toners to electrostatic images carried by the surface of an image member as said image member moves through a single fixed development position, said developing device comprising:
- a plurality of development units, each unit containing a dry developer including a toner of a color different from the other units, and each unit including an applicator assembly and a mixing device mounted in the unit, said applicator assembly being movable toward and away from the mixing device, and
- said units being fixed in a side-by-side arrangement in a movable carriage, said carriage being movable in a lateral direction bringing the applicator of each unit through a position in which it is aligned with said development position.
An electrostatographic apparatus having a photoconductive drum rotatable past a series of stations including charging and exposing stations for creating a series of electrostatic images on said drum and a development station for toning said series of electrostatic images with dry toners of different colors to create a series of single color toner images of different color and a transfer station for transferring said color toner images to a receiving surface in registration to create a multicolor toner image, said developing station including:
- a plurality of developing units, each unit including an applicator including magnetic means for moving developer having a magnetic component through toner applying relation with an electrostatic image and means for supplying such developer to said applicator,
- a carriage for holding said units fixed with respect to each other, said carriage being movable through a path bringing each unit, one after another into alignment with an operative position with respect to said drum, and
- means for moving the applicator of a development unit into said operative position with said drum by moving said applicator toward said drum relative to the developer supplying means in the applicator's respective unit.
A developing device for applying toner to an electrostatic image carried on an image member as said image moves through a development position, said developing device comprising:
- a laterally movable carriage,
- a plurality of developing units fixed in a lateral side-by-side relationship in said carriage, each unit having a developer chamber for holding a dry, two-component developer having a magnetic component, means in said chamber for mixing developer and an applicator positioned in an opening from the chamber, said applicator including magnetic means for presenting developer to said development position,
- means for driving said carriage laterally to move each unit through a position in which it is aligned with said development position, and
- means for moving the applicator of each unit away from its mixing means toward said development position as such unit is positioned in alignment with said development position.
A developing device for applying toner to an electrostatic image carried on an image drum as said image moves through a development position located generally at the bottom of said drum, said development device comprising:
- a plurality of developing units, fixed in horizontal side-by-side relation on a movable carriage, each unit having a development chamber for holding dry, two-component developer, means for mixing developer in said chamber and an applicator at the top of the chamber having a magnetic means for presenting developer including a magnetic component to the development position,
- means for driving said carriage through a generally horizontal path to move each unit, one after another, through a position directly blow the development position, and
- means for moving the applicator of each unit relative to its mixing means in an upward direction as its unit is positioned below said development position by said driving means.
A developing device comprising a carriage, a plurality of developing units arranged side by side on said carriage means for moving said carriage in a lateral direction to move said units one after another into a position aligned with a development position of an image member, means for moving a portion of an aligned unit in a direction transverse to the lateral direction and away from the rest of the unit and into operative relation with an image member at said development position, said means for moving a portion of an aligned unit in a transverse direction including a wedge located generally opposite said developing device from said development position and an engaging means on each developing unit positioned to engage said wedge as its unit becomes aligned with the developing position, and means associated with each unit for moving said portion of said unit into operative relation with said drum at said developing position in response to engagement of said wedge by said engaging means.
A developing unit including a housing for holding a supply of developer, said housing having an opening, an applicator block positioned in said opening and an applicator supported by said applicator block for applying developer from said housing to an electrostatic image outside said housing, said block and applicator being movable away from said supply of developer from a recessed position to an extended position in which extended position said applicator is operative for applying developer to an electrostatic image, and flexible sealing means between said block and said housing for preventing the escape of developer from said housing but permitting relative movement between said block and housing.
A color printer or copier having a rotatable drum, means for forming a series of electrostatic images on said drum and a developing device for developing each of said series of images with toner of a color different from each of said other images, said developing device including a plurality of developing units each unit including a housing for holding a supply of developer, said housing having an opening, an applicator block positioned in said opening and an applicator supported by said applicator block for applying developer from said housing to an electrostatic image outside said housing, said block and applicator being movable away from said supply of developer from a recessed position to an extended position in which extended position said applicator is operative for applying developer to an electrostatic image, and flexible sealing means between said block and said housing for preventing the escape of developer from said housing but permitting relative movement between said block and housing, and said developing device further including means for moving said units one after another into alignment with said drum and means for moving the block of an aligned unit to its extended position to bring its applicator into developing relation with an electrostatic image carried by said drum.
A method of developing an electrostatic image carried on a surface utilizing a developing unit having a supply of a developer having a dry particulate magnetic component, an applicator including magnetic means for moving the developer and a developer supply means for supplying developer to said applicator, said method comprising:
- moving said surface to transport said electrostatic image through a development position,
- moving said applicator away from said supply means and into developing relation with said electrostatic image at said development position, and
- actuating said applicator and supply means to move developer through said development position to develop said electrostatic image.
A developing unit for applying toner to an electrostatic image from a supply of dry particulate developer having a magnetic component, said unit including a housing for holding said supply of developer, said housing having an opening, an applicator block positioned in said opening and an applicator supported by said applicator block and having magnetic means for applying developer from said housing to an electrostatic image outside said housing, said block and applicator being movable away from said supply of developer from a recessed position to an extended position in which extended position said applicator is operative for applying developer from said supply to an electrostatic image, spring means urging said block toward its extended position, and means for controlling the application of said spring to said block to control the position of the block between its recessed and extended positions.
A developing unit for applying toner to an electrostatic image from a supply of dry particulate developer having a magnetic component, said unit including an applicator having a magnetic core and a nonmagnetic shell, at least one of said core and shell being rotatable to move the developer through development relation with the electrostatic image, said applicator being movable away from said supply of developer from a recessed position to an extended position in which extended position said applicator is operative for applying developer to the electrostatic image.
Dependencies are inferred from the claim text.