EP0629924A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electrostatographic single-pass multiple-station printer
Assignee: Xeikon NV
•
Filing: 1994-06-13
•
Granted: —
•
Expires: 2014-06-13
Abstract
Abstract An electrostatographic single-pass multiple station multi-colour printer for forming an image onto a web (12), eg of paper, is described. The printer comprises a plurality of toner image-producing electrostatographic printing stations (A, B, C, D, E) each having rotatable endless surface means (26) such as the photoconductive surface of a cylindrical drum (24) onto which a toner image can be formed. The paper web (12) is conveyed in succession past the printing stations (A, B, C, D, E). The speed and tension of the web (12) is controlled while it is running past the printing stations (A, B, C, D, E). Guiding rollers (36) which determine for the web (12) wrapping angles (ω) of about 15° about the drum surface. A corona device transfers the toner image on each drum onto the web (12). The corona device, the wrapping angles ω and the web tension are such that adherent contact of the web (12) with the drum surface (26) is such that the moving paper web (12) controls the peripheral speed of the drum in synchronism with the movement of said web. Slippage between the drum surface (26) and the paper web (12) is thereby eliminated, enabling accurate registration of superimposed images on the paper web (12).
Inventors
- 👤 Jan Julien Irma De Bock
- 👤 Etienne Marie De Cock
- 👤 Lucien Amedé De Schamphelaere
- 👤 Rudy Dirk Leroy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 18:20
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/65; G03G15/01; G03G15/0142; G03G15/0178; G03G15/0194; G03G15/22; G03G15/23; G03G15/231; G03G15/238; G03G2215/00; G03G2215/00362; G03G2215/00367; G03G2215/00413; G03G2215/00443; G03G2215/00451; G03G2215/00455; G03G2215/00535; G03G2215/00654; G03G2215/01; G03G2215/0103; G03G2215/0119
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
168 words
An electrostatographic single-pass multiple station printer for forming an image onto a web, which comprises: - a plurality of toner image-producing electrostatographic stations (A, B, C, D, E) each having rotatable endless surface means (26) onto which a toner image can be formed; - means for conveying the web in succession past said stations (A, B, C, D, E); - means (22, 11) for controlling the speed and tension of the web (12) while it is running past said stations (A, B, C, D, E); - guiding means (36) which determine for the web wrapping angles (ω) about the rotatable surface means (26); - transfer means (34) for transferring the toner image on each rotatable surface means (26) onto the web (12), characterised in that in said printer adherent contact of said web (12) with said rotatable endless surface means (26) is such that the movement of said web (12) controls the peripheral speed of said surface means (26) in synchronism with the movement of said web (12).
Claim 2
Dependent Claim
15 words
A printer according to Claim 1, wherein said guiding means (36) comprise guide roller means.
Claim 3
Dependent Claim
31 words
A printer according to claim 1 or 2, wherein said transfer means is a corona discharge device (34) providing electrostatic adhesion between the web (12) and the endless surface means (26).
Claim 4
Dependent Claim
41 words
A printer according to any preceding claim, wherein the web (12) is a final support for the toner images and is unwound from a roll (14), image-fixing means (16) being provided for fixing the transferred toner images on the web (12).
Claim 5
Dependent Claim
39 words
A printer according to claim 4, which further comprises a roll stand (13) for unwinding a roll of web (12) to be printed in the printer, and a web cutter (20) for cutting the printed web (12) into sheets.
Claim 6
Dependent Claim
61 words
A printer according to claim 1 or 2, wherein the web is a temporary support in the form of an endless belt (115), and wherein the printer further comprises transfer means (122) for transferring the images formed on the belt (115) onto a final support (118), image-fixing means (121) being provided for fixing the transferred images on the final support (118).
Claim 7
Dependent Claim
15 words
A printer according to claim 6, wherein the final support (118) is in sheet form.
Claim 8
Dependent Claim
67 words
A printer according to any preceding claim, wherein each endless surface means comprises a photoconductive surface and each image-producing station (A, B, C, D, E,) further comprises: - means (28) for charging said endless surface means (26); - means (30, 32) for forming an electrostatic latent image on said endless surface means (26); and - a development station (32) for depositing toner onto the electrostatic latent image.
Claim 9
Dependent Claim
33 words
A printer according to claim 8, wherein the means (28) for charging the endless surface means (26) at each image-producing station is capable of charging each endless surface means to the same polarity.
Claim 10
Dependent Claim
48 words
A printer according to any preceding claim, wherein each image-producing station (A, B, C, D, E) comprises a driven rotatable magnetic developing brush (33) and a driven rotatable cleaning brush (43), both in frictional contact with the endless surface means (26), said brushes rotating in mutually opposite directions.
Claim 11
Dependent Claim
44 words
A printer according to claim 10, wherein the extents of frictional contact of the developing brush (33) and the cleaning brush (43) with said endless surface means (26) are such that the resultant torque transmitted to the endless surface means (26) is substantially zero.
Claim 12
Dependent Claim
45 words
A printer according to claim 10 or 11, wherein the position of at least one of said brushes relative to said endless rotatable surface means (26) is adjustable thereby to adjust the extent of frictional contact between that brush and said endless surface means (26).
Claim 13
Dependent Claim
23 words
A printer according to any preceding claim, wherein the endless surface means (26) is formed by the circumferential surface of a drum (24).
Claim 14
Dependent Claim
64 words
A printer according to any one of claims 1 to 13, wherein said image-producing stations are arranged in two sub-groups (A to E and A' to E') that are passed in succession by the moving web (12), one sub-group forming an image on one web side and the other sub-group forming an image on the other web side, thereby to enable sequential duplex printing.
Claim 15
Dependent Claim
28 words
A printer according to claim 14, which further comprises at least one idler roller (54, 55, 56, 57) for reversing the direction of web travel between the sub-groups.
Claim 16
Dependent Claim
51 words
A printer according to any one of claims 1 to 12, wherein said image-producing stations are arranged in two sub-groups, the rotatable surface means (26) of one subgroup (A to E) forming guide roller means (36) for the other sub-group (A' to E'), and vice-versa, thereby to enable simultaneous duplex printing.
Claim 17
Dependent Claim
32 words
A printer according to any one of claims 14 to 16, wherein said image-producing stations of the sub-groups (A to E and A' to E') are arranged in substantially mutually parallel configuration.
Claim 18
Dependent Claim
25 words
A printer according to claim 17, wherein said image-producing stations (A, B, C, D, E) of each subgroup are arranged in a substantially vertical configuration.
Claim 19
Dependent Claim
24 words
A printer according to any preceding claim, which is a colour printer comprising cyan, yellow, magenta and black printing stations (A, B, C, D).
Claim 20
Dependent Claim
16 words
A printer according to any preceding claim, wherein said wrapping angles (ω) are at least 5°.
Claim 21
Dependent Claim
100 words
A printer according to any preceding claim, further comprising a rotatable contact roller (150) for contacting the web while it has an electrostatically charged toner particle image on at least that surface thereof which is adjacent said contact roller (150), wherein said contact roller (150) is associated with electrostatic charging means (153) capable of providing on the surface of said contact roller (150) an electrostatic charge having the same polarity as the charge polarity of the toner particles on the adjacent surface of said web before contact of said web (12) with the surface (154) of said contact roller (150).
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.