System for wiping a photoconductive surface

1. A system for wiping a photoconductive surface, the photoconductive surface moving relative to the system, the system comprising:

at least two wiper blades comprising a first wiper blade and a second wiper blade;

the first wiper blade to contact the photoconductive surface and to wipe at least some of particles and fluid from the photoconductive surface; and

the second wiper blade to contact the photoconductive surface and to wipe at least some of the particles and fluid that have passed the first wiper blade, from the photoconductive surface;

wherein the first wiper blade includes at least one perforation forming a passage through the wiper blade;

wherein at least the first wiper blade includes a number of perforations forming a number of passages through the wiper blade and distributed along a width of the first wiper blade, the width of the first wiper blade extending parallel to a contact line between the first wiper blade and the photoconductive surface; and

wherein a density of the perforations in at least one side edge region of at least the first wiper blade is higher than in a middle region of at least the first wiper blade wherein the side edge region is adjacent an end of the contact line and the middle region is in the middle between the two ends of the contact line.

2. The system of claim 1 wherein one, two, three, four or five perforations are provided in each side edge region of at least the first wiper blade and no perforations are provided in the middle region of at least the first wiper blade.

3. The system of claim 1 wherein the side edge region extends along about 5% to about 10% of the width of at least the first wiper blade.

4. The system of claim 1 wherein the at least one perforation has a circular, oval or rectangular cross section.

5. The system of claim 1 wherein the second wiper blade is configured in a way identical or substantially identical to the first wiper blade wherein the passages of the second wiper blade are at least partially blocked when the second wiper blade is engaged to the system.

6. The system of claim 5 further including a wiper holder supporting the first and second wiper blades wherein the wiper holder at least partially blocks the passages provided in the second wiper blades.

7. A system for wiping a photoconductive surface, the photoconductive surface moving relative to the system, the system comprising:

at least two wiper blades comprising a first wiper blade and a second wiper blade;

the first wiper blade to contact the photoconductive surface and to wipe at least some of particles and fluid from the photoconductive surface; and

the second wiper blade to contact the photoconductive surface and to wipe at least some of the particles and fluid that have passed the first wiper blade, from the photoconductive surface;

wherein the first wiper blade includes at least one perforation forming a passage through the wiper blade;

wherein the at least one perforation has a circular, oval or rectangular cross section; and

wherein the at least one perforation is spaced from a front edge of at least the first wiper blade by a distance which is between one time the diameter of the perforation to about four times the diameter of the perforation, wherein the front edge of at least the first wiper blade is the edge facing the photoconductive surface.

8. A system for wiping a photoconductive surface, the photoconductive surface moving relative to the system, the system comprising:

at least two wiper blades comprising a first wiper blade and a second wiper blade;

the first wiper blade to contact the photoconductive surface and to wipe at least some of particles and fluid from the photoconductive surface; and

the second wiper blade to contact the photoconductive surface and to wipe at least some of the particles and fluid that have passed the first wiper blade, from the photoconductive surface;

wherein the first wiper blade includes at least one perforation forming a passage through the wiper blade; and

wherein the second wiper blade includes at least one perforation forming a passage through the second wiper blade said passage being at least partially blocked.

9. An apparatus comprising a member having a photoconductive surface and a system for wiping the photoconductive surface, the photoconductive surface moving relative to the system, the system comprising:

at least two wiper blades comprising a first wiper blade and a second wiper blade; and

a wiper holder supporting the first and second wiper blades; the first wiper blade to contact the photoconductive surface and to wipe at least some of particles and fluid from the photoconductive surface; and

the second wiper blade to contact the photoconductive surface and to wipe at least some of the particles and fluid that have passed the first wiper blade, from the photoconductive surface;

wherein the first wiper blade includes a number of perforations forming a number of passages distributed along a width of the first wiper blade, the width of the first wiper blade extending parallel to a contact line between the first wiper blade and the photoconductive surface;

wherein the second wiper blade includes a number of perforations forming a number of passages distributed along a width of the second wiper blade, the width of the second wiper blade extending parallel to a contact line between the second wiper blade and the photoconductive surface; and

wherein the passages extend in a direction of relative movement between the wiper blades and the photoconductive surface, and wherein the wiper holder at least partially blocks the passages formed in the second wiper blade and exposes the passages formed in the first wiper blade.

10. The apparatus of claim 9 , wherein the fluid is a maintenance fluid and the apparatus further comprises at least one applicator unit to provide the maintenance fluid to the photoconductive surface, wherein the at least one applicator unit is arranged along a movement path of the photoconductive surface upstream of the first and second wiper blades.

11. The apparatus of claim 10 , wherein the applicator unit comprises a sponge applicator which is arranged relative to the first wiper blade to direct fluid passing through the passages in the first wiper blade to the sponge applicator.

12. A method of cleaning a photoconductive surface, comprising:

applying imaging oil to a photo imaging plate (PIP) drum having a photoconductive surface;

turning the PIP drum past a first wiper blade that contacts the photoconductive surface of the PIP drum and wipes at least some of ink residues and imaging oil from the photoconductive surface; and

turning the PIP drum past a second wiper blade that contacts the photoconductive surface and wipes at least some of the ink residues and imaging oil that have passed the first wiper blade from the photoconductive surface;

wherein the first wiper blade includes at least one passage to transmit part of the ink residues and imaging oil during wiping of the photoconductive surface;

wherein at least the first wiper blade includes a number of passages through the wiper blade distributed along a width of the first wiper blade, the width of the first wiper blade extending parallel to a contact line between the first wiper blade and the photoconductive surface; and

wherein a density of the passages in at least one side edge region of at least the first wiper blade is higher than in a middle region of at least the first wiper blade wherein the side edge region is adjacent an end of the contact line and the middle region is in the middle between the two ends of the contact line.

13. The method of claim 12 , wherein the first wiper blade includes a plurality of passages distributed parallel to a wiping edge region thereof to transmit part of the ink residues and the imaging oil.