Electrographic recording method and devices for performing this method

Claim 2

The method of claim 2, wherein said mixture also serves as a counter electrode in generating charge images.

Claim 3

The method of claim 3, wherein a record carrier is used which is suitable for repeated use, and wherein residues of an image formed by the developer on the side of the carrier remote from said image electrodes is removed after transfer of the image to an image carrier for the purpose of obtaining a copy.

Claim 4

The method of claim 4, wherein the developer is also used for removing the image residues and for generating an electric field having a sufficient intensity for removing the charge image for the purpose of preparing the carrier for another recording cycle.

Claim 5

The method of claim 5, wherein a portion of the developer serving to develop the charge images is mixed with a portion of the developer serving to remove the image residues.

Claim 6

The method of claim 6, wherein the carrier particles in the developer consist of magnetizable material having an average particle size ranging from approximately 30 Mu m to 200 Mu m.

Claim 7

Apparatus for electrographic recording in which charge images are formed on a record carrier by means of gas-discharge phenomena, comprising: A. a chamber containing developer having a rear wall supporting said record carrier and forming a write/erase head; B. image electrodes and erasing electrodes disposed in said rear wall; C. transport devices disposed in the chamber for transporting the developer to areas within the chamber for charging and developing the record carrier and for transporting the developer to areas within the chamber for the purpose of cleaning and erasing said carrier, said transport means serving the additional purpose of mixing the developer; and D. electrical means connected to said electrodes, said chamber, and said transport means for generating electrical fields for image production and erasure.

Claim 8

The apparatus of claim 8, wherein said transport devices are a pair of rotating cylinders containing permanent magnets.

Claim 9

The apparatus of claim 8, wherein said erasing electrodes are plate-shaped.

Claim 10

The apparatus of claim 8, wherein the rear wall of said chamber contains insulating material for electrically isOlating said electrodes and other plate elements.

Claim 11

The apparatus of claim 8, wherein the image electrodes are needle-shaped.

Claim 12

The apparatus of claim 8, wherein the rear wall of said chamber contains metal bodies for avoiding tribo-electrical charging of the record carrier and for charge compensation.