Developer roller

• US 4,558,943 A
• Filed: 11/07/1983
• Issued: 12/17/1985
• Est. Priority Date: 11/07/1983
• Status: Expired due to Fees

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Patz, Herbert S.
• Primary Examiner(s): Braun, Fred L.
• Application Number:
  US06/549,094
• Time in Patent Office: 771 Days
• Field of Search: 355/3 R, 355/3 DD, 118/656, 118/657, 118/658, 118/661
• US Class Current: 399/274
• CPC Class Codes: G03G 15/0812 characterised by the developer regulating means, e.g. structure of doctor blade
• CPC Class Codes: G03G 15/0818 characterised by the structure of the donor member, e.g. surface properties
• CPC Class Codes: G03G 15/0928 relating to the shell, e.g. structure, composition

Abstract

An apparatus in which a latent image recorded on an image receiving member is developed. A developer roller transports the marking particles into the development zone. The developer roller has the exterior surface thereof roughened forming a multiplicity of peaks extending outwardly therefrom with a coating of polymeric material filling the space between adjacent peaks. A blade is positioned to have the free end thereof contacting the peaks on the developer roller. The blade has a plurality of apertures therein through which the marking particles pass. In this way, the thickness of the layer of marking particles on the developer roller is controlled.

Claims

1. An apparatus for developing a latent image recorded on an image receiving member, including:

a housing defining a chamber for storing a supply of marking particles therein;

means for transporting the marking particles from the chamber in said housing to a development zone closely adjacent to the latent image recorded on the image receiving member, said transporting means comprising a support member having the exterior surface thereof roughened forming a multiplicity of peaks extending outwardly therefrom with a coating of a polymeric material filling the space between adjacent peaks so that at least a portion of the peaks of the support member extend beyond the coating of polymeric material thereon; and

means for controlling the thickness of the layer of marking particles on said transporting means, said controlling means having a free edge contacting the peaks of the support member of said transporting means and being spaced from the polymeric material coated thereon.

2. An apparatus according to claim 1, wherein said controlling means includes a blade.

3. An apparatus according to claim 2, wherein the support member is made from a material having a hardness greater than the hardness of the polymeric coating thereon.

4. An apparatus according to claim 3, wherein the movement of the marking particles over the polymeric coating induces a triboelectric charge in the marking particles.

5. An apparatus according to claim 4, wherein the peaks of the support member of said transporting means comprise about 5% of the surface area of the support member.

6. An apparatus according to claim 5, wherein the spacing between adjacent peaks of the support member of said transporting means is about 10 microns.

7. An apparatus according to claim 6, wherein the support member of said transporting means includes a tubular member.

8. An apparatus according to claim 7, wherein said transporting means includes an elongated magnetic member disposed interiorly of and spaced from said tubular member.

9. An apparatus according to claim 8, wherein said blade includes a plurality of substantially equally spaced apertures through which the marking particles pass prior to being transported into the development zone.

10. An apparatus according to claim 9, wherein said blade is made from a stainless steel material.

11. An apparatus according to claim 10, wherein said tubular member is made from a metal material.

12. An apparatus according to claim 11, wherein the free edge of said blade has a hard, low friction coating plated thereon.

13. An apparatus according to claim 12, wherein the polymeric coating on said tubular member is made from a polyvinylidene fluoride based material.

14. An electrophotographic printing machine of the type having a photoconductive member arranged to have a latent image recorded thereon, wherein the improvement includes:

a housing defining a chamber for storing a supply of marking particles therein;

means for transporting the marking particles from the chamber in said housing to a development zone closely adjacent to the latent image recorded on the photoconductive member, said transporting means comprising a support member having the exterior surface thereof roughened forming a multiplicity of peaks extending outwardly therefrom with a coating of polymeric material filling the space between adjacent peaks so that at least a portion of the peaks of the support member extend beyond the coating of polymeric material thereon; and

means for controlling the thickness of the layer of marking particles on said transporting means, said controlling means having a free edge contacting the peaks of the support member of said transporting means and being spaced from the polymeric material coated thereon.

15. A printing machine according to claim 14, wherein said controlling means includes a blade.

16. A printing machine according to claim 15, wherein the support member is made from a material having a hardness greater than the hardness of the polymeric coating thereon.

17. A printing machine according to claim 16, wherein movement of the marking particles on the polymeric coating induces a triboelectric charge therein.

18. A printing machine according to claim 17, wherein the peaks of the support member of said transporting means comprise about 5% of the surface area of the support member.

19. A printing machine according to claim 18, wherein the spacing between adjacent peaks of the support member of said transporting means is about 10 microns.

20. A printing machine according to claim 19, wherein the support member of said transporting means includes a tubular member.

21. A printing machine according to claim 20, wherein said transporting means includes an elongated magnetic member disposed interiorly of and spaced from said tubular member.

22. A printing machine according to claim 21, wherein said blade includes a plurality of substantially equally spaced apertures through which the marking particles pass prior to being transported into the development zone.

23. A printing machine according to claim 22, wherein said blade is made from a stainless steel material.

24. A printing machine according to claim 23, wherein said tubular member is made from a metal material.

25. A printing machine according to claim 24, wherein the free edge of said blade has a hard, low friction coating plated thereon.

26. A printing machine according to claim 25, wherein the polymeric coating on said tubular member is made from a polyvinylidene fluoride.