Apparatus and method for controlling the supply of fluid

Abstract

An apparatus for controlling the amount of fluid to be transferred, contains a first rotating device which has a first fluid-transferring section in its circumferential direction, a second rotating device which has a second fluid-transferring section in its circumferential direction, and a control device for setting the phase position between the first fluid-transferring section and the second fluid-transferring section. The control device is configured for accelerating and retarding a rotation of the first rotating device periodically.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic illustration of one embodiment of an inking unit according to the invention, in which the rotating apparatuses are not phase-shifted with respect to one another; and

FIG. 2 is a diagrammatic illustration of the embodiment shown in FIG. 1, with a phase shift of 45° between the rotating apparatuses.

Claims

1. An apparatus for controlling an amount of fluid to be transferred, the apparatus comprising: a first rotating device having a first fluid-transferring section in a circumferential direction;a second rotating device having a second fluid-transferring section in a circumferential direction; anda control device for setting a phase position between said first fluid-transferring section and said second fluid-transferring section, said control device configured for accelerating and retarding a rotation of said first rotating device periodically.

2. The apparatus according to claim 1, wherein: said first rotating device has a first non-fluid-transferring section adjoining said first fluid-transferring section in the circumferential direction; andsaid second rotating device has a second non-fluid-transferring section adjoining said second fluid-transferring section in the circumferential direction.

3. The apparatus according to claim 2, wherein said first and second fluid-transferring sections and said first and second non-fluid-transferring sections in each case have a same sheet length.

4. The apparatus according to claim 2, wherein at least one of said first fluid-transferring section and said second fluid-transferring section is formed from an elastically deformable material.

5. The apparatus according to claim 4, wherein said elastically deformable material has a cutout formed therein and at least one of said first non-fluid-transferring section and said second non-fluid-transferring section is formed by said cutout disposed in said elastically deformable material.

6. The apparatus according to claim 2, wherein at least one of said first fluid-transferring section and said second fluid-transferring section is formed from a substantially dimensionally stable material.

7. The apparatus according to claim 6, wherein said substantially dimensionally stable material has cutout formed therein and at least one of said first non-fluid-transferring section and said second non-fluid-transferring section is formed by said cutout disposed in said substantially dimensionally stable material.

8. The apparatus according to claim 2, wherein: at least one of said first fluid-transferring section and said second fluid-transferring section has a surface for revecing the fluid; andat least one of said first non-fluid-transferring section and said second non-fluid-transferring section has a surface which does not receive or rejects the fluid.

9. The apparatus according to claim 1, wherein said first rotating device forms a transfer nip with said second rotating device.

10. The apparatus according to claim 1, wherein at least one of said first rotating device and said second rotating device is selected from the group consisting of rollers and cylinders.

11. The apparatus according to claim 1, wherein the fluid to be transferred is selected from the group consisting of printing ink, dampening solution and varnish.

12. The apparatus according to claim 4, wherein said elastically deformable material is selected from the group consisting of rubber and a rubber-like material.

13. The apparatus according to claim 6, wherein said substantially dimensionally stable material is selected from the group consisting of metal, plastic and ceramic.

14. The apparatus according to claim 8, wherein: said surface of at least one of said first fluid-transferring section and said second fluid-transferring section for revecing the fluid is oleophilic; andsaid surface of at least one of said first non-fluid-transferring section and said second non-fluid-transferring section which does not receive or rejects the fluid is one of oleophobic and hydrophilic.

15. The apparatus according to claim 9, wherein said first fluid-transferring section forms a synchronized transfer nip with said second fluid-transferring section.

16. An inking unit, comprising: an apparatus for controlling an amount of fluid to be transferred, the apparatus including: a first rotating device having a first fluid-transferring section in a circumferential direction;a second rotating device having a second fluid-transferring section in a circumferential direction; anda control device for setting a phase position between said first fluid-transferring section and said second fluid-transferring section, said control device configured for accelerating and retarding a rotation of said first rotating device periodically.

17. A dampening unit, comprising: an apparatus for controlling an amount of fluid to be transferred, the apparatus including: a first rotating device having a first fluid-transferring section in a circumferential direction;a second rotating device having a second fluid-transferring section in a circumferential direction; anda control device for setting a phase position between said first fluid-transferring section and said second fluid-transferring section, said control device configured for accelerating and retarding a rotation of said first rotating device periodically.

18. A machine which processes printing material, comprising: an apparatus for controlling an amount of fluid to be transferred, the apparatus including: a first rotating device having a first fluid-transferring section in a circumferential direction;a second rotating device having a second fluid-transferring section in a circumferential direction; anda control device for setting a phase position between said first fluid-transferring section and said second fluid-transferring section, said control device configured for accelerating and retarding a rotation of said first rotating device periodically.

19. A method for controlling an amount of fluid to be transferred, which comprises the steps of: applying a fluid onto a first rotating device having a first fluid-transferring section in a circumferential direction;transferring at least one portion of the fluid onto a second rotating device having a second fluid-transferring section in a circumferential direction;controlling the at least one portion by setting a phase position between the first fluid-transferring section and the second fluid-transferring section; andaccelerating and retarding periodically a rotation of the first rotating device.

20. The method according to claim 19, which further comprises setting an overlapping sheet length of the first fluid-transferring section and the second fluid-transferring section.