Electrographic recording method and apparatus with control of toner quantity at recording region

Claim 2

Electrographic apparatus for use with dry, electronically conductive toner including: first and second electrodes in spaced opposing relationship wherein said first electrode is stationary; a receptor recording member spaced from said first electrode for providing a recording region between said first electrode and said receptor recording member, the receptor recording member adapted for making electronic contact with said second electrode, said receptor recording member adapted for movement relative to said first electrode; means for supplying the toner to said recording region in a regular or relatively uniform rate for deposition on said receptor recording member as toner images; force producing means for providing a temporally relatively constant force at said first electrode acting on the toner when supplied to said recording region to cause the toner to span the space between said first electrode and said receptor recording member to establish an electronically conductive path via the toner between said first electrode and said receptor recording member; and means adapted to apply recording electrical potential signals to said first electrode relative to said second electrode concurrent with the operation of said force means and movement of said receptor recording member relative to said first electrode for causing some of the toner of said recording region to be held on said receptor recording member as toner images, said force producing means also providing a temporally relatively constant force for removing a portion of the toner from said recording region and from electronic contact with the toner at said recording region for maintaining a constant quantity of toner in said recording region, the toner removed from said recording region by said force means being toner that accumulates in excess of said constant quantity due to changes in the amount of toner supplied to said recording region and the amount of toner held on said receptor recording member as toner images.

Claim 3

Electrographic apparatus in accordance with claim 1 wherein said force producing means for providing said second mentioned temporally relatively constant force includes a conduit having an opening presented adjacent said recording region, said conduit adapted for connection to a vacuum source.

Claim 4

Electrographic apparatus in accordance with claim 1 wherein the toner is magnetically attractable and said temporarily relatively constant forces are magnetic forces.

Claim 5

Electrographic apparatus in accordance with claim 1 wherein the toner is magnetically attractable and said first mentioned temporally relatively constant force is a magnetic force.

Claim 6

Electrographic apparatus in accordance with claims 3 or 4 wherein said first electrode includes magnetically permeable material.

Claim 7

Electrographic apparatus in accordance with claims 3 or 4 wherein said first electrode includes magnetically permeable material that is permanently magnetized for providing said first mentioned temporally relative constant force.

Claim 8

Electrographic apparatus in accordance with claim 1 wherein the toner is magnetically attractable and said force producing means for providing the temporally relatively constant forces includes at least one stationary magnetic source positioned adjacent said first electrode and spaced from said recording region.

Claim 9

Electrographic apparatus in accordance with claim 7 wherein said magnetic source has two magnetic poles, one of which is positioned adjacent said first electrode with the other of said magnetic poles spaced at a greater distance from said first electrode than said one magnetic pole.

Claim 10

Electrographic apparatus in accordance with claim 7 wherein a conduit, having an opening, is adapted for connection with a vacuum source with said opening presented between said magnetic source and said recording region.

Claim 11

Electrographic apparatus in accordance with claim 1 wherein the toner is magnetically attractable and said force producing means for providing temporally relatively constant forces includes a first stationary magnetic source positioned adjacent said first electrode and a second stationary magnetic source spaced at a greater distance from said first electrode than said first magnetic source.

Claim 12

Electrographic apparatus in accordance with claim 1 and further including a non-image toner removal means positioned at a point remote from said recording region and adjacent said receptor recording member for removing non-image toner from said receptor surface.

Claim 13

Electrographic apparatus in accordance with claim 11 wherein the toner is magnetically attractable and said non-image toner removal means provides a magnetic force for removing non-image toner from said receptor recording member.

Claim 14

Electrographic apparatus in accordance with claim 11 wherein the toner is magnetically attractable and said non-image toner removal means provides air flow directed for dislodging non-image toner on said receptor recording member and includes a magnetic field producing means positioned for removing toner dislodged from said receptor recording member by said air flow.

Claim 15

Electrographic apparatus for use with dry, magnetically attractable, electronically conductive toner including: a receptor recording member; first and second electrode means in spaced opposing relationship with said receptor recording member spaced from said first electrode, wherein said first electrode means is stationary, to provide a recording region between said receptor recording member and said first electrode and adapted for making electronic contact with said second electrode, said receptor recording member adapted for movement relative to said first electrode means, said first electrode means including means for providing a magnetic field at said recording region that is concentrated at said first electrode; means for supplying the toner to said recording region in a regular and uniform manner whereby the toner when supplied to said recording region, is attracted toward said first electrode means by said magnetic field causing said toner to span the space between said first electrode means and said receptor recording member to establish an electronically conductive path via the toner between said first electrode and said receptor recording member; means adapted to apply recording electrical potential signals to said first electrode relative to said second electrode concurrent with movement of said receptor recording member relative to said first electrode means for causing some of the toner at said recording region to be held on said receptor recording member as toner images; force producing means for providing a temporally relative constant force acting on the toner when presented to said recording region to remove a portion of the toner from said recording region and from electronic contact with toner in said recording region for maintaining a constant quantity of toner in said recording region, the toner removed from said recording region by said force producing means being toner that accumulates in excess of said constant quantity due to changes in the amount of toner supplied to said recording region and the amount of toner held on said receptor recording member as toner images.

Claim 16

Electrographic apparatus for use with dry, magnetically attractable, electronically conductive toner including: a receptor recording member; first and second electrode means in spaced opposing relationship with said receptor recording member spaced from said first electrode, wherein said first electrode means is stationary, to provide a recording region between said receptor recording member and said first electrode and adapted for making electronic contact with said second electrode, said receptor recording member adapted for movement relative to said first electrode means, said first electrode means including means for providing a magnetic field at said recording region that is concentrated at said first electrode; means for supplying the toner to said recording region in a regular and uniform manner whereby the toner when supplied to said recording region, is attracted toward said first electrode means by said magnetic field causing said toner to span the space between said first electrode means and said receptor recording member to establish an electronically conductive path via the toner between said first electrode and said receptor recording member; means adapted to apply recording electrical potential signals to said first electrode relative to said second electrode concurrent with movement of said receptor recording member relative to said first electrode means for causing some of the toner at said recording region to be held on said receptor recording member as toner images; force producing means for providing a temporally relative constant force acting on the toner when presented to said recording region to remove a portion of the toner from said recording region and from electronic contact with toner in said recording region for maintaining a constant quantity of toner in said recording region, the toner removed from said recording region by said force producing means being toner that accumulates in excess of said constant quantity due to changes in the amount of toner supplied to said recording region and the amount of toner held on said receptor recording member as toner images.

Claim 17

Electrographic apparatus in accordance with claim 14 wherein said force producing means includes a conduit adapted for connection with a vacuum source, said conduit having an opening for receiving said portion of the toner.

Claim 18

Electrographic apparatus in accordance with claim 14 wherein said force producing means includes a stationary magnetic source spaced from said recording region on said first electrode means side of said recording region.

Claim 19

Electrographic apparatus in accordance with claim 16 wherein said magnetic source is a permanent magnet.

Claim 20

Electrographic apparatus in accordance with claim 16 wherein said magnetic source is an electro-magnet.

Claim 21

Electrographic apparatus in accordance with claim 14 and further includes a non-image toner removal means positioned at a point remote from said recording region and adjacent said receptor recording member for removing non-image toner from said receptor surface.

Claim 22

Electrographic apparatus in accordance with claim 19 wherein said non-image toner removal means provides a magnetic force for removing non-image toner from said receptor recording member.

Claim 23

Electrographic apparatus in accordance with claim 19 wherein said non-image toner removal means provides air flow directed for dislodging non-image toner on said receptor recording member and includes a magnetic field producing means for removing toner dislodged from said receptor recording member by said air flow.

Claim 24

An electrographic method for producing a toner image at the surface of a receptor recording member using dry, magnetically attractable, electronically conductive toner including the steps of arranging first and second electrodes in spaced opposed relationship, wherein said first electrode is stationary, with a receptor recording member interposed and spaced from said first electrode with electronic contact provided between said receptor recording member and said second electrode while providing movement of said receptor recording member relative to said first electrode as the toner is supplied in a regular or relatively uniform manner to the region between said first electrode and said receptor recording member while a temporally relative constant force is provided which acts on the toner to cause the toner to span the space between said first electrode and said receptor recording member causing the toner to provide an electronically conductive path between said first electrode and said second electrode; applying recording electrode potential signals to said first electrode relative to said second electrode, while said movement of said receptor recording member relative to said first electrode is provided, causing toner to be held to said recording receptor member in accordance with signals to produce a toner image; and providing a temporally relatively constant force which acts on the toner in the region between said first electrode and said receptor recording member for removing a portion of the toner from said region and out of electronic contact with the toner in said region for maintaining a constant quantity of toner in said region, the toner removed from said region being toner that accumulates in excess of said constant quantity due to changes in the amount of toner supplied to said region and the amount of toner held on said receptor recording member as toner images.

Claim 25

An electrographic method for producing a toner image at the surface of a receptor recording member using dry, magnetically attractable, electronically conductive toner including the steps of arranging first and second electrodes in spaced opposed relationship, wherein said first electrode is stationary, with a receptor recording member interposed and spaced from said first electrode with electronic contact provided between said receptor recording member and said second electrode while providing movement of said receptor recording member relative to said first electrode as the toner is supplied in a regular or relatively uniform manner to the region between said first electrode and said receptor recording member while a temporally relative constant force is provided which acts on the toner to cause the toner to span the space between said first electrode and said receptor recording member causing the toner to provide an electronically conductive path between said first electrode and said second electrode; applying recording electrode potential signals to said first electrode relative to said second electrode, while said movement of said receptor recording member relative to said first electrode is provided, causing toner to be held to said recording receptor member in accordance with signals to produce a toner image; and providing a temporally relatively constant force which acts on the toner in the region between said first electrode and said receptor recording member for removing a portion of the toner from said region and out of electronic contact with the toner in said region for maintaining a constant quantity of toner in said region, the toner removed from said region being toner that accumulates in excess of said constant quantity due to changes in the amount of toner supplied to said region and the amount of toner held on said receptor recording member as toner images.

Claim 26

An electrographic method in accordance with claim 22 including the further step of providing a non-image toner removal force at a point remote from said region for removing non-image toner from said receptor recording member.