Method and device for cleaning an electrode matrix of an electrographic printer

Claim 1

A method of improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced by an electrode matrix, having electrodes, which temporarily produces electrical fields for attraction of pigment particles of a toner towards an information carrier, the matrix being disposed between a developer roller and a backing electrode, the method comprising the steps of: exposing the electrodes of the electrode matrix, during at least a portion of time between printing of subsequent information carriers, to means for producing a cleaning force, wherein the means for producing the cleaning force comprises a bellowed container which, when expanded, produces a stream of air which vacuums the pigment particles from the electrode matrix; and transporting the pigment particles to the developer roller and away from the electrode matrix by the cleaning force to remove the pigment particles from the electrode matrix.

Claim 2

A method of improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced by an electrode matrix, having electrodes, which temporarily produces electrical fields for attraction of pigment particles of a toner towards an information carrier, the matrix being disposed between a developer roller and a backing electrode, the method comprising the steps of: exposing the electrodes of the electrode matrix, during at least a portion of time between printing of subsequent information carriers, to means for producing a cleaning force, wherein the means for producing the cleaning force comprises a bellowed container which, when expanded, produces a stream of air which vacuums the pigment particles from the electrode matrix; and transporting the pigment particles to the developer roller and away from the electrode matrix by the cleaning force to remove the pigment particles from the electrode matrix.

Claim 5

A method of improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced by an electrode matrix, having electrodes, which temporarily produces electrical fields for attraction of pigment particles of a toner towards an information carrier, the matrix being disposed between a developer roller and a backing electrode, the method comprising the steps of: exposing the electrodes of the electrode matrix, during at least a portion of time between printing of subsequent information carriers, to means for producing a cleaning force, wherein the means for producing the cleaning force comprises a magnetic core positioned within the developer roller, the magnetic core generating a magnetic field for removing the pigment particles from the electrode matrix; and transporting the pigment particles to the developer roller and away from the matrix by the cleaning force to remove the pigment particles from the electrode matrix.

Claim 6

A method of improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced by an electrode matrix, having electrodes, which temporarily produces electrical fields for attraction of pigment particles of a toner towards an information carrier, the matrix being disposed between a developer roller and a backing electrode, the method comprising the steps of: exposing the electrodes of the electrode matrix, during at least a portion of time between printing of subsequent information carriers, to means for producing a cleaning force, wherein the means for producing the cleaning force comprises a magnetic core positioned within the developer roller, the magnetic core generating a magnetic field for removing the pigment particles from the electrode matrix; and transporting the pigment particles to the developer roller and away from the matrix by the cleaning force to remove the pigment particles from the electrode matrix.

Claim 8

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a bellowed pigment particle container and means for expanding or compressing the container, wherein, when the container is expanded, a stream of air is produced to remove the pigment particles from the electrode matrix.

Claim 9

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a bellowed pigment particle container and means for expanding or compressing the container, wherein, when the container is expanded, a stream of air is produced to remove the pigment particles from the electrode matrix.

Claim 12

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnet disposed within the developer roller, the magnet being movable between a passive position wherein the magnet is spaced from the slotted area and an active position wherein said magnet is at the slotted area, the magnet generating a magnetic field to remove the pigment particles from the electrode matrix.

Claim 13

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnet disposed within the developer roller, the magnet being movable between a passive position wherein the magnet is spaced from the slotted area and an active position wherein said magnet is at the slotted area, the magnet generating a magnetic field to remove the pigment particles from the electrode matrix.

Claim 14

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnetic core disposed within the developer roller, the magnetic core having at least one decontamination pole which produces a magnetic field in the slotted area, the magnetic field having an extension which corresponds to an extension of the electrode matrix.

Claim 15

A device for improving printing quality and performance of an electrographic printer in which a latent electrical charge pattern of electrical signals is produced in a print unit having an electrode matrix comprising electrodes and being disposed between a developer roller and a backing electrode, the electrode matrix temporarily producing electrical fields for attraction of pigment particles of a toner towards an information carrier, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnetic core disposed within the developer roller, the magnetic core having at least one decontamination pole which produces a magnetic field in the slotted area, the magnetic field having an extension which corresponds to an extension of the electrode matrix.

Claim 17

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprising a bellowed pigment particle container and means for expanding or compressing the container, wherein, when the container is expanded, a stream of air is produced to remove the pigment particles from the electrode matrix.

Claim 18

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprising a bellowed pigment particle container and means for expanding or compressing the container, wherein, when the container is expanded, a stream of air is produced to remove the pigment particles from the electrode matrix.

Claim 20

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnet disposed within the developer roller, the magnet being movable between a passive position wherein the magnet is spaced from the slotted area and an active position wherein said magnet is at the slotted area, the magnet producing a magnetic field to remove the pigment particles from the electrode matrix.

Claim 21

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnet disposed within the developer roller, the magnet being movable between a passive position wherein the magnet is spaced from the slotted area and an active position wherein said magnet is at the slotted area, the magnet producing a magnetic field to remove the pigment particles from the electrode matrix.

Claim 22

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnetic core disposed within the developer roller, the magnetic core having at least one decontamination pole which produces a magnetic field in the slotted area, the magnetic field having an extension which corresponds to an extension of the electrode matrix.

Claim 23

A device for improving the printing quality and performance of electrographical printers in which a latent electrical charge pattern of electrical signals is produced in a print unit, the print unit having an electrode matrix disposed between a particle carrier and a backing electrode, the electrode matrix comprising a screen or grid of electrodes connected through a controlling device to a voltage source and a plurality of passages which are partly opened and closed electrostatically in response to control signals corresponding to image information applied to the electrode matrix for the controlled transmission of pigment particles of toner to an information carrier which is located between the background electrode and a developer roller, the background electrode and developer roller each being connected to at least one voltage source for producing electrostatic fields therebetween, the device comprising: a slotted area in the print unit in close proximity to the electrode matrix; and means connected to the slotted area for producing a cleaning force to transport the pigment particles toward the developer roller and away from the electrode matrix, wherein the means for producing the cleaning force comprises a magnetic core disposed within the developer roller, the magnetic core having at least one decontamination pole which produces a magnetic field in the slotted area, the magnetic field having an extension which corresponds to an extension of the electrode matrix.