EP0286305A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Improvements in or relating to lithographic printing
Assignee: Seiken Graphics Inc
•
Filing: 1988-03-30
•
Granted: —
•
Expires: 2008-03-30
Abstract
Abstract Ink is applied to a lithographic printing plate (2) from an engraved roller (8) provided with a plurality of cells in its surface (10). Ink is introduced into the cells by an inking device comprising a pressurised substantially closed ink duct defined by an axially extending sealing member (41) contacting or close to the surface (10) and an axially extending doctor blade (42) in contact with the surface (10).
Inventors
- 👤 Richard Procter Greenwood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 22:46
CPC Classifications
B; B41; B41F; B41F31/00; B41F31/02; B41F31/08
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
222 words
A lithographic printing press comprising: a plate cylinder (1) mounted for rotation about its cylindrical axis (3) and adapted to receive a lithographic printing plate (2), a means (13) of applying an aqueous fountain solution to the plate (2), a means of transferring ink from an ink source (17) to the plate (2), and a means (6) of transferring ink from the plate (2) to material (28) to be printed characterised in that the means for transferring ink from the ink source (17) to the plate (2) comprises (i) an engraved roller (8) mounted for rotation about its cylindrical axis (9) and having a cylindrical surface (10) provided with a plurality of cells, (ii) an inking device for applying ink to the surface (10) comprising (a) a substantially closed axially extending ink duct for containing ink under pressure, said ink duct being bounded by said surface (10), an axially extending doctor blade (42) in contact with said surface, and an axially extending sealing member (41), (b) a means (19,20,18) of supplying ink from the ink source (17) to said duct and thence into contact with said surface (10) and into said cells, and (c) a means (21) of returning ink from said duct to said source (17), and (iii) a means (11) of transferring ink from said cells to the plate (2).
Claim 2
Dependent Claim
222 words
A lithographic printing press comprising: a plate cylinder (1) mounted for rotation about its cylindrical axis (3) and adapted to receive a lithographic printing plate (2), a means (13) of applying an aqueous fountain solution to the plate (2), a means of transferring ink from an ink source (17) to the plate (2), and a means (6) of transferring ink from the plate (2) to material (28) to be printed characterised in that the means for transferring ink from the ink source (17) to the plate (2) comprises (i) an engraved roller (8) mounted for rotation about its cylindrical axis (9) and having a cylindrical surface (10) provided with a plurality of cells, (ii) an inking device for applying ink to the surface (10) comprising (a) a substantially closed axially extending ink duct for containing ink under pressure, said ink duct being bounded by said surface (10), an axially extending doctor blade (42) in contact with said surface, and an axially extending sealing member (41), (b) a means (19,20,18) of supplying ink from the ink source (17) to said duct and thence into contact with said surface (10) and into said cells, and (c) a means (21) of returning ink from said duct to said source (17), and (iii) a means (11) of transferring ink from said cells to the plate (2).
Claim 3
Dependent Claim
25 words
A press as claimed in claim 1 wherein the axially extending sealing member (41) is spaced from the roller surface by less than 0.5 mm.
Claim 4
Dependent Claim
74 words
A press as claimed in claim 1 or 2 wherein the ink duct includes a constriction defined by a protruding edge (44) adjacent to the surface (10) of the engraved roller (8) to divide the duct into a first zone 45 and a second zone 46, said means of supplying ink to said duct being connected to said first zone (45) and said means of returning ink being connected to said second zone (46).
Claim 5
Dependent Claim
23 words
A press as claimed in claim 3 wherein the protruding edge (44) is spaced from the surface (10) by less than 0.5 mm.
Claim 6
Dependent Claim
33 words
A press as claimed in claim 3 or 4 wherein a means (22) is provided to control the pressure generated in said second zone (46) due to rotation of the engraved roller (8).
Claim 7
Dependent Claim
21 words
A press as claimed in claim 5 wherein said means (22) to control the pressure is a pressure relief valve (22).
Claim 8
Dependent Claim
28 words
A press as claimed in any preceding claim and including a plurality of said inking devices arranged side by side along the axial length of the roller (8).
Claim 9
Dependent Claim
17 words
A press as claimed in claim 7 wherein each inking device has a separate ink source (17).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.