Printing machine

Abstract

A printing machine includes an inking unit having a roller and a doctor-type ink fountain associated with the roller. The doctor-type ink fountain has an adjustable rear wall for setting an ink level of printing ink stored in the doctor-type ink fountain. The rear wall has a flow profile for flow-mechanically influencing the printing ink.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a partly sectional, side-elevational view of a doctor-type ink fountain which has an adjustable rear wall with a flow profile that has been adjusted into a maintenance position withdrawn from a roller;

FIG. 1B is a view similar to FIG. 1, showing the adjustable rear wall having the flow profile in an operating position in the vicinity of the roller; and

FIG. 2 is a rear-perspective view of the doctor-type ink fountain.

Claims

1. A printing machine, comprising: an inking unit including a roller and a doctor-type ink fountain associated with said roller;said doctor-type ink fountain having an adjustable rear wall for setting an ink level of printing ink stored in said doctor-type ink fountain; andsaid rear wall having a flow profile for flow-mechanically influencing the printing ink.

2. The printing machine according to claim 1, wherein: said doctor-type ink fountain has a doctor with a doctor blade; andsaid rear wall is mounted for adjustment as desired into a first position, in which said ink level lies above said doctor blade, and into a second position, in which said ink level lies below said doctor blade.

3. The printing machine according to claim 2, wherein: said doctor-type ink fountain has a fountain base; andsaid rear wall is mounted for pivoting about a rotary joint into said first position and into said second position, and said rotary joint is disposed above said fountain base.

4. The printing machine according to claim 2, wherein said flow profile and said roller together form a bottleneck located above said doctor blade when said rear wall is in said first position.

5. The printing machine according to claim 4, wherein said flow profile has an outer corner determining said bottleneck, and said outer corner has an angle greater than 45° and less than 135°.

6. The printing machine according to claim 5, wherein said angle of said outer corner is approximately 90°.

7. The printing machine according to claim 1, wherein said flow profile has an inner corner.

8. The printing machine according to claim 7, wherein said inner corner has an angle of at least 90°.

9. The printing machine according to claim 1, which further comprises a film, and at least one element for securing a contact existing between said rear wall and said film.

10. The printing machine according to claim 9, wherein said doctor-type ink fountain has a fountain base, and said element is a cushion disposed between said film and said fountain base.

11. The printing machine according to claim 10, wherein said film is a disposable article to be disposed of regularly when cleaning said doctor-type ink fountain.

12. The printing machine according to claim 9, wherein said rear wall has a metallically hard sliding surface, with which said rear wall rests on said film to produce said contact.

13. The printing machine according to claim 9, wherein the printing ink forms offset printing ink supplies stored in said doctor-type ink fountain, and said film and said rear wall delimit one of the offset printing ink supplies.

14. The printing machine according to claim 10, wherein said fountain base has a concavely curved surface facing said film.

15. The printing machine according to claim 1, wherein said inking unit is an anilox inking unit and said roller is an engraved roller.