Patent US3640248A successfully refreshed from Google Patents.
US3640248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic magnetic developing apparatus
Assignee: Xerox Corp
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Filing: 1969-06-04
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Granted: 1972-02-08
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Expires: 1989-06-04
Abstract
Abstract An arrangement of spaced magnetic brushes for developing latent electrostatic images wherein the magnetic fields associated with the brushes overlap so that magnetizable carrier particles are carried from one brush to the other across the space therebetween thereby presenting a continuous magnetic blanket of developing material during development.
Inventors
- 👤 William B Nielander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:36
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
175 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable cylindrical members mounted in spaced relation with an open space therebetween, said membeRs having their axes generally in parallel and being arranged in spaced tangential relationship to the surface, each of said members having associated therewith means for producing a magnetic field across a portion of the periphery thereof and across said surface as the same moves, said lastnamed means being arranged to produce bristles of magnetizable particles on each of the members during rotation thereof, means for supplying a mixture of developing material having magnetizable particles and developing powder electrostatically carried by the particles to at least one of the members thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 2
Independent Claim
175 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable cylindrical members mounted in spaced relation with an open space therebetween, said membeRs having their axes generally in parallel and being arranged in spaced tangential relationship to the surface, each of said members having associated therewith means for producing a magnetic field across a portion of the periphery thereof and across said surface as the same moves, said lastnamed means being arranged to produce bristles of magnetizable particles on each of the members during rotation thereof, means for supplying a mixture of developing material having magnetizable particles and developing powder electrostatically carried by the particles to at least one of the members thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 3
Independent Claim
212 words
An apparatus for developing a latent electrostatic image on a moving photoconductive insulating surface including: a housing for containing a supply of developing material comprising magnetizable carrier particles and electrostatically adhering developing particles, a plurality of cylindrical members mounted in spaced relation in the housing with an open space therebetween and arranged adjacent to and in spaced tangential relationship with said photoconductive insulating surface with their longitudinal axes generally normal to the path of movement of said surface, means for rotating said members, means supported within the cylindrical members for producing a magnetic field across at least a portion of the periphery of each of the members, and wherein the magnetic fields produced overlie one another whereby upon rotation thereof causing the formation of bristles of developing material upon said portion of each member arranged to contact said surface during movement thereof, said means for producing a magnetic field being cooperable with said rotating members for producing movement of bristles along said portion of one of the members across said open space between the same and an adjacent member and along said portion of the adjacent member with the developing material remaining in contact with said surface thereby presenting a partially unsupported magnetic developing blanket during development of the latent electrostatic image.
Claim 4
Independent Claim
212 words
An apparatus for developing a latent electrostatic image on a moving photoconductive insulating surface including: a housing for containing a supply of developing material comprising magnetizable carrier particles and electrostatically adhering developing particles, a plurality of cylindrical members mounted in spaced relation in the housing with an open space therebetween and arranged adjacent to and in spaced tangential relationship with said photoconductive insulating surface with their longitudinal axes generally normal to the path of movement of said surface, means for rotating said members, means supported within the cylindrical members for producing a magnetic field across at least a portion of the periphery of each of the members, and wherein the magnetic fields produced overlie one another whereby upon rotation thereof causing the formation of bristles of developing material upon said portion of each member arranged to contact said surface during movement thereof, said means for producing a magnetic field being cooperable with said rotating members for producing movement of bristles along said portion of one of the members across said open space between the same and an adjacent member and along said portion of the adjacent member with the developing material remaining in contact with said surface thereby presenting a partially unsupported magnetic developing blanket during development of the latent electrostatic image.
Claim 5
Independent Claim
176 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable cylindrical members mounted in spaced relation with an open space therebetween, said members having their axes generally in parallel and being arranged in spaced tangential relationship to the surface, each of said members having supported therein means for producing a magnetic field across a portion of the periphery thereof and across said surface as the same moves, said last named means being arranged to produce bristles of magnetizable particles on each of the members during rotation thereof, at least one of said members being positioned to receive a supply of developing material having magnetizable particles and developing powder electrostatically carried by the particles thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 6
Independent Claim
176 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable cylindrical members mounted in spaced relation with an open space therebetween, said members having their axes generally in parallel and being arranged in spaced tangential relationship to the surface, each of said members having supported therein means for producing a magnetic field across a portion of the periphery thereof and across said surface as the same moves, said last named means being arranged to produce bristles of magnetizable particles on each of the members during rotation thereof, at least one of said members being positioned to receive a supply of developing material having magnetizable particles and developing powder electrostatically carried by the particles thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 7
Independent Claim
169 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable elongated members mounted in spaced relation with an open space therebetween, said members having their longitudinal dimension generally in parallel and being arranged in spaced relationship to the surface, each of said members having associatEd therewith means for producing a magnetic field over a portion of and along said surface as the same moves, said last-named means being arranged to produce bristles of magnetizable particles on each of the members, means for supplying a mixture of developing material having magnetizable particles and developing powder electrostatically carried by the particles to at least one of the members thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 8
Independent Claim
169 words
An apparatus for developing a movable surface bearing a latent electrostatic charge image including: a plurality of rotatable elongated members mounted in spaced relation with an open space therebetween, said members having their longitudinal dimension generally in parallel and being arranged in spaced relationship to the surface, each of said members having associatEd therewith means for producing a magnetic field over a portion of and along said surface as the same moves, said last-named means being arranged to produce bristles of magnetizable particles on each of the members, means for supplying a mixture of developing material having magnetizable particles and developing powder electrostatically carried by the particles to at least one of the members thereby initiating the formation of bristles thereon, said means for producing magnetic fields being arranged wherein the magnetic influence upon one member diminishes within a stronger magnetic influence of the other thereby causing the movement of bristles from said one member to said other member across said open space therebetween upon rotation of said members.
Claim 9
Independent Claim
215 words
An apparatus for developing a latent electrostatic image on a moving photoconductive insulating surface including: a housing for containing a supply of developing material comprising magnetizable carrier particles and electrostatically adhering developing particles, a plurality of rotatable elongated members mounted in spaced relation in the housing with an open space therebetween and arranged adjacent to and in spaced relationship with said photoconductive insulating surface with their longitudinal axes generally normal to the path of movement of said surface, means supported within the members for producing a magnetic field over at least a portion of each of the members and causing the formation of bristles of developing material upon said portion of each member the bristles being arranged to contact said surface during movement thereof, said members being disposed in close parallel relationship whereby the magnetic fields associated with said members overlap, said means for producing a magnetic field being cooperable with said members upon rotation of said members for producing movement of bristles along said portion of one of the members across said open space between the same and an adjacent member and along said portion of the adjacent member with the developing material remaining in contact with said surface thereby presenting a partially unsupported magnetic developing blanket during development of the latent electrostatic image.
Claim 10
Independent Claim
215 words
An apparatus for developing a latent electrostatic image on a moving photoconductive insulating surface including: a housing for containing a supply of developing material comprising magnetizable carrier particles and electrostatically adhering developing particles, a plurality of rotatable elongated members mounted in spaced relation in the housing with an open space therebetween and arranged adjacent to and in spaced relationship with said photoconductive insulating surface with their longitudinal axes generally normal to the path of movement of said surface, means supported within the members for producing a magnetic field over at least a portion of each of the members and causing the formation of bristles of developing material upon said portion of each member the bristles being arranged to contact said surface during movement thereof, said members being disposed in close parallel relationship whereby the magnetic fields associated with said members overlap, said means for producing a magnetic field being cooperable with said members upon rotation of said members for producing movement of bristles along said portion of one of the members across said open space between the same and an adjacent member and along said portion of the adjacent member with the developing material remaining in contact with said surface thereby presenting a partially unsupported magnetic developing blanket during development of the latent electrostatic image.
Claim 11
Dependent Claim
166 words
In an electrostatic reproduction machine having means for producing latent electrostatic images on an element supporting latent images and for processing the images into copies of an original including: a first magnetic developing brush arranged for contacting and applying developing material upon the images being processed, a second magnetic developing brush arranged for contacting and applying developer material upon the images after the same have been contacted by said first brush, said first and second magnetic brushes comprising a pair of rotatable roll members having an open space therebetween and means to establish a magnetic field over at least a portion of each member, the magnetic fields associated with said members overlapping across said open space, said second brush exerting a stronger magnetic influence, at a point in said open space, than said first brush, for receiving developing material therefrom. whereby said second brush is arranged to receive its supply of developing material from said first brush across the space therebetween upon rotation of said members.
Claim 12
Dependent Claim
166 words
In an electrostatic reproduction machine having means for producing latent electrostatic images on an element supporting latent images and for processing the images into copies of an original including: a first magnetic developing brush arranged for contacting and applying developing material upon the images being processed, a second magnetic developing brush arranged for contacting and applying developer material upon the images after the same have been contacted by said first brush, said first and second magnetic brushes comprising a pair of rotatable roll members having an open space therebetween and means to establish a magnetic field over at least a portion of each member, the magnetic fields associated with said members overlapping across said open space, said second brush exerting a stronger magnetic influence, at a point in said open space, than said first brush, for receiving developing material therefrom. whereby said second brush is arranged to receive its supply of developing material from said first brush across the space therebetween upon rotation of said members.
Claim 13
Dependent Claim
161 words
In an electrostatic reproduction machine having means for producing latent electrostatic images on an element supporting latent images and for processing the images into copies of an original including: a first magnetic developing brush arranged for contacting and applying magnetizable developing material upon the images being processed, a second magnetic developing brush arranged for contacting and applying developer material upon the images after the same have been contacted by said first brush, said first and second magnetic brushes comprising a pair of rotatable roll members having an open space therebetween and means to esTablish a magnetic field over at least a portion of each member, the magnetic fields associated with said members overlapping across said open space, said second brush exerting a stronger magnetic influence, at a point in said open space, than said first brush, for receiving developing material therefrom. whereby the magnetizable material is transported across said open space from one brush to another upon rotation of said members.
Claim 14
Dependent Claim
161 words
In an electrostatic reproduction machine having means for producing latent electrostatic images on an element supporting latent images and for processing the images into copies of an original including: a first magnetic developing brush arranged for contacting and applying magnetizable developing material upon the images being processed, a second magnetic developing brush arranged for contacting and applying developer material upon the images after the same have been contacted by said first brush, said first and second magnetic brushes comprising a pair of rotatable roll members having an open space therebetween and means to esTablish a magnetic field over at least a portion of each member, the magnetic fields associated with said members overlapping across said open space, said second brush exerting a stronger magnetic influence, at a point in said open space, than said first brush, for receiving developing material therefrom. whereby the magnetizable material is transported across said open space from one brush to another upon rotation of said members.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |