Apparatus for cleaning a corona discharge strand

Claim 2

In a corona discharge apparatus: a corona discharge strand having at least one axial portion effective for depositing charge onto the surface of a member moving relative to said corona discharge strand and having another portion thereof remote from said surface; means for effecting axial translation of said strand for changing that portion of the strand effective for depositing charge onto said surface, said means for effecting axial translation including first and second spaced rotatable members; a junction forming said strand into an endless loop around said rotatable members and being part of the remote portion of the strand, the junction being substantially larger than the strand; means for sensing the junction; control means responsive to sensing of the junction and alternately effecting said translation in opposite directions; means disposed adjacent the strand for cleaning accumulated debris therefrom in response to axial translation of the strand.

Claim 3

The apparatus of claim 1 wherein said strand cleaning means comprises a pair of brushes pressing against the strand from opposite sides of the strand.

Claim 4

The apparatus of claim 2 wherein said pair of brushes are offset from each other axially of said strand.

Claim 5

The apparatus of claim 1 including a pair of bridge members bearing against said strand and being spaced apart axially of the strand to define said effective charge depositing portion of the strand therebetween.

Claim 6

The apparatus of claim 1 wherein said translation means comprise drive means coupled to said first rotatable member.

Claim 7

The apparatus of claim 5 wherein said second rotatable member is electrically conductive, and further including a power source for supplying a corona-producing electric potential, and means for applying said corona-producing electrical potential to said strand through said second rotatable member.

Claim 8

The apparatus of claim 5 wherein said remote portion of the strand is substantially wound around said first rotatable member and comprises at least one turn, and first and second laterally-spaced parts of said loop define a pair of effective charge-depositing lengths of said strand, the wound portion of the strand being of a length such that the junction is sensed only after cleaned lengths of strand lie adjacent the surface of said moving member.

Claim 9

The apparatus of claim 7 wherein said junction is a knot and said drive means is a reversible motor having an output drive shaft coupled to said first rotatable member and further including a reversing control for the motor, coMprising a pair of switches each having an actuator with a slotted end straddling a respective part of the remote portion of the strand and being effective to engage said knot as the strand is translated.

Claim 10

In an electrostatic copy production machine: a corona discharge strand having at least one axial portion effective for depositing charge onto the surface of an imaging member positioned proximate said axial portion of the corona discharge strand and having another portion thereof remote from said imaging member; means for effecting relative movement of said imaging member laterally of said strand; means for effecting axial translation of the strand for changing that portion of the strand effective for depositing charge onto the imaging member, said means for effecting axial translation including first and second rotatable members, at least one of the rotatable members being driven during copy production; a junction forming said strand into an endless loop around said rotatable members and being part of the remote portion of the strand, the junction being substantially larger than the strand; means for sensing the junction; control means responsive to sensing of the junction and alternately effecting said translation in opposite directions; means disposed adjacent the strand for cleaning accumulated debris therefrom in response to axial translation of the strand; means for forming a charge image pattern on the imaging member; and means for developing said charge image pattern.

Claim 11

In an electrostatic copy production machine: a corona discharge strand having at least one axial portion effective for depositing charge onto the surface of an imaging member positioned proximate said axial portion of the corona discharge strand and having another portion thereof remote from said imaging member; means for effecting relative movement of said imaging member laterally of said strand; means for effecting axial translation of the strand for changing that portion of the strand effective for depositing charge onto the imaging member, said means for effecting axial translation including first and second rotatable members, at least one of the rotatable members being driven during copy production; a junction forming said strand into an endless loop around said rotatable members and being part of the remote portion of the strand, the junction being substantially larger than the strand; means for sensing the junction; control means responsive to sensing of the junction and alternately effecting said translation in opposite directions; means disposed adjacent the strand for cleaning accumulated debris therefrom in response to axial translation of the strand; means for forming a charge image pattern on the imaging member; and means for developing said charge image pattern.