Image developing apparatus

Claim 2

Apparatus for developing an electrostatic latent image comprised of electrostatic charges selectively distributed on a photoconductive plate, comprising: a translatable surface adapted to receive charged toner particles; fixedly disposed electrode means, said electrode means being spaced apart from said surface in face to face relation therewith; means for producing a uniformly varying voltage potential along the surface of said electrode means to induce a uniformly varying electrostatic field transversely of said surface and said electrode means; means for introducing toner particles into the space between said surface and said electrode means; means for translating said translatable surface past said electrode means such that said surface successively traverses a decreasing electrostatic field followed by an oppositely directed increasing electrostatic field in the vicinity of said electrode means for exerting decreasing electrostatic forces on residual toner particles adhering to said translatable surface to remove said residual toner particles from said surface when said surface traverses said decreasing electrostatic field and for exerting increasing electrostatic forces on introduced toner particles to uniformly deposit said toner particles on said surface when said surface traverses said increasing electrostatic field; and means for selectively transferring said uniformly deposited toner particles from said surface to said electrostatic charges in conformity with the distribution of said electrostatic charges on said photoconductive plate.

Claim 3

Apparatus for cleaning and applying toner particles to a surface, comprising: electrode means fixedly disposed in spaced apart relation with respect to said surface; said electrode means including a cermet resistive coated surface; means for translating said surface past said electrode means; means for projecting developer material into the space between said surface and said electrode means thereby dislodging toner particles adhering to said surface; and means for inducing a uniformly varying potential across said electrode means to establish a uniformly varying electrostatic field transversely of said surface and said electrode means for exerting first electrostatic forces exhibiting uniformly decreasing magnitudes in the direction of translation of said surface on dislodged toner particles to urge said toner particles from said surface toward said electrode means and for exerting second electrostatic forces exhibiting uniformly increasing magnitudes in the direction of translation of said surface on toner particles projected into said space to urge said toner particles toward said surface; said inducing means comprising a constant voltage supply coupled to opposite ends of said electrode means for applying the voltage supplied by said constant voltage supply across said electrode means.

Claim 4

Apparatus for cleaning and applying toner particles to a surface, comprising: electrode means fixedly disposed in spaced apart relation with respect to said surface; said electrode means including a cermet resistive coated surface; means for translating said surface past said electrode means; means for projecting developer material into the space between said surface and said electrode means thereby dislodging toner particles adhering to said surface; and means for inducing a uniformly varying potential across said electrode means to establish a uniformly varying electrostatic field transversely of said surface and said electrode means for exerting first electrostatic forces exhibiting uniformly decreasing magnitudes in the direction of translation of said surface on dislodged toner particles to urge said toner particles from said surface toward said electrode means and for exerting second electrostatic forces exhibiting uniformly increasing magnitudes in the direction of translation of said surface on toner particles projected into said space to urge said toner particles toward said surface; said inducing means comprising a constant voltage supply coupled to opposite ends of said electrode means for applying the voltage supplied by said constant voltage supply across said electrode means.

Claim 5

In a development system, an apparatus for cleaning and applying toner particles to a surface, comprising: electrode means fixedly disposed in spaCed apart relation with respect to said surface; means for translating said surface past said electrode means; means for projecting developer material into the space between said surface and said electrode means thereby dislodging toner particles adhering to said surface; means for inducing a uniformly varying potential across said electrode means to establish a uniformly varying electrostatic field transversely of said surface and said electrode means for exerting first electrostatic forces exhibiting uniformly decreasing magnitudes in the direction of translation of said surface on dislodged toner particles to urge said toner particles from said surface toward said electrode means and for exerting second electrostatic forces exhibiting uniformly increasing magnitudes in the direction of translation of said surface on toner particles projected into said space to urge said toner particles toward said surface; a photoconductor having a latent image thereon; and means for transferring the toner particles on said surface to said photoconductor.

Claim 6

In a development system, an apparatus for cleaning and applying toner particles to a surface, comprising: electrode means fixedly disposed in spaCed apart relation with respect to said surface; means for translating said surface past said electrode means; means for projecting developer material into the space between said surface and said electrode means thereby dislodging toner particles adhering to said surface; means for inducing a uniformly varying potential across said electrode means to establish a uniformly varying electrostatic field transversely of said surface and said electrode means for exerting first electrostatic forces exhibiting uniformly decreasing magnitudes in the direction of translation of said surface on dislodged toner particles to urge said toner particles from said surface toward said electrode means and for exerting second electrostatic forces exhibiting uniformly increasing magnitudes in the direction of translation of said surface on toner particles projected into said space to urge said toner particles toward said surface; a photoconductor having a latent image thereon; and means for transferring the toner particles on said surface to said photoconductor.

Claim 7

Apparatus for developing an electrostatic latent image comprised of electrostatic charges selectively distributed on a photoconductive plate, comprising: fixedly disposed electrode means having spaced apart first and second portions, said electrode means being spaced apart from said plate in face to face relation therewith, means for translating said plate in a direction passing said electrode from said first portion to said second portion, means for introducing toner particles into the space between said plate and said electrode means, means for applying first voltage potential to said electrode first portion which is greater than the voltage potential of said electrostatic charges, means for applying a second voltage potential to said electrode second portion which is less than the voltage potential of said electrostatic charges, and means for producing a voltage potential decreasing from said first voltage potential to said second voltage potential along the surface of said electrode between said first and second portions thereof to set up a varying field between said plate and said electrode in a direction to attract toner particles toward said electrode to clean said plate and thereafter set up a varying field between said plate and said electrode in the opposite direction to attract toner particles to said plate to develop said latent image.

Claim 8

Apparatus for developing an electrostatic latent image comprised of electrostatic charges selectively distributed on a photoconductive plate, comprising: fixedly disposed electrode means having spaced apart first and second portions, said electrode means being spaced apart from said plate in face to face relation therewith, means for translating said plate in a direction passing said electrode from said first portion to said second portion, means for introducing toner particles into the space between said plate and said electrode means, means for applying first voltage potential to said electrode first portion which is greater than the voltage potential of said electrostatic charges, means for applying a second voltage potential to said electrode second portion which is less than the voltage potential of said electrostatic charges, and means for producing a voltage potential decreasing from said first voltage potential to said second voltage potential along the surface of said electrode between said first and second portions thereof to set up a varying field between said plate and said electrode in a direction to attract toner particles toward said electrode to clean said plate and thereafter set up a varying field between said plate and said electrode in the opposite direction to attract toner particles to said plate to develop said latent image.

Claim 9

Apparatus for developing an electrostatic latent image comprised of electrostatic charges selectively distributed on a photoconductive plate, comprising: a translatable surface located adjacent said plate and adapted to receive charged toner particles, fixedly disposed electrode means having spaced apart first and second portions, said electrode means being spaced apart from said surface in face to face relation therewith, means for translating said surface in a direction passing said electrode from said first portion to said second portion, means for introducing toner particles into the space between said surface and said electrode means, means for applying a first voltage potential to said translatable surface, means for applying a second voltage potential to said electrode first portion which is greater than said first voltage potential, means for applying a third voltage potential to said electrode second portion which is less than said first voltage potential, means for producing a voltage potential decreasing from said second voltage potential to said first voltage potential along the surface of said electrode between said first and second portions thereof to set up a varying field between said translatable surface and said electrode in a direction to attract toner particles toward said electrode to clean said translatable surface and thereafter set up a varying field between said translatable surface and said electrode in the opposite direction to attract toner particles to said translatabLe surface to develop said translatable surface, and means for transferring toner particles from said translatable surface to develop said latent image.

Claim 10

Apparatus for developing an electrostatic latent image comprised of electrostatic charges selectively distributed on a photoconductive plate, comprising: a translatable surface located adjacent said plate and adapted to receive charged toner particles, fixedly disposed electrode means having spaced apart first and second portions, said electrode means being spaced apart from said surface in face to face relation therewith, means for translating said surface in a direction passing said electrode from said first portion to said second portion, means for introducing toner particles into the space between said surface and said electrode means, means for applying a first voltage potential to said translatable surface, means for applying a second voltage potential to said electrode first portion which is greater than said first voltage potential, means for applying a third voltage potential to said electrode second portion which is less than said first voltage potential, means for producing a voltage potential decreasing from said second voltage potential to said first voltage potential along the surface of said electrode between said first and second portions thereof to set up a varying field between said translatable surface and said electrode in a direction to attract toner particles toward said electrode to clean said translatable surface and thereafter set up a varying field between said translatable surface and said electrode in the opposite direction to attract toner particles to said translatabLe surface to develop said translatable surface, and means for transferring toner particles from said translatable surface to develop said latent image.