GB2281537A

GB2281537A - Apparatus for multi-colour printing

Info

Publication number: GB2281537A
Application number: GB9418056A
Authority: GB
Inventors: David George Upton
Original assignee: UPTON MECHANICAL DESIGN LIMITE
Current assignee: UPTON MECHANICAL DESIGN LIMITE
Priority date: 1993-09-07
Filing date: 1994-09-07
Publication date: 1995-03-08
Anticipated expiration: 2014-09-07
Also published as: GB2281537B; GB9418056D0; GB9318565D0

Abstract

The apparatus is suitable for printing continuous stationery and includes two plate cylinders (4), a common blanket cylinder (5), and an impression cylinder (2), each plate cylinder preferably being supplied with two coloured inks from a respective supply (3). The continuous stationery is fed between the cylinders (2) and (5) at one axial location, and is then reversed twice and fed between them at a second axial location. The second two colours are applied before the first colours have dried. <IMAGE>

Description

COLOUR PRINTING The invention relates to printing and in particular to printing of continuous stationery.

It is an object of this invention to print continuous stationery with a number of colours, to enhance the colour effect, in a single pass.

According to the invention in one aspect there is provided printing apparatus comprising at least two printing means arranged in side by side relation, each to apply a separate colour, each printing means being in contact with a common blanket roller, and feed means for passing continuous stationery past the blanket roller to print at least two colours on the stationery.

Preferably each colour printing means comprises a print tower arranged to provide two colours to the blanket roller.

Preferably the feed means is arranged to turn over the stationery whereby printing takes place on both sides of the stationery.

Preferably the feed means includes pivotally mounted arms, over which the stationery is passed, arranged diagonally across the apparatus. As a result the printing may be done quickly by each print means in succession and the apparatus may be compact and simple in design.

Preferably the floor of the apparatus below the printing towers is dished to provide sufficient space for the continuous stationery to be slackened if required.

Preferably the printing apparatus includes a means to adjust the timing of the apparatus to accommodate a plurality of form sizes of continuous stationery.

In a specific aspect the invention provides colour printing apparatus for continuous stationery, comprising a cabinet housing two print towers arranged in side-by-side relation, each tower having a blanket cylinder, a roller extending across the cabinet to provide counter pressure to both blanket cylinders, a fixed roller at each side of the common roller and adjacent an outer wall of the cabinet, and an auxiliary roller beyond the fixed roller on each wall of the cabinet and arranged for pivotal movement with respect thereto.

In another aspect the invention provides a method of printing colours on continuous stationery comprising passing the stationery past one printing means so as to apply a first colour and then passing the stationery past a second printing means whereby a second colour is applied in addition to the first, before the first colour has dried..

In order that the invention may be well understood it will now be described by way of example only and reference to the accompanying diagrammatic drawings in which: Figure 1 is a diagrammatic illustration of the apparatus of the invention; and Figure 2 is a vertical section through one apparatus of the invention.

The apparatus comprises a cabinet 1 housing two colour print towers arranged in side by side relation and sharing a common roller 2. Each print tower comprises two supplies 3 of different inks which are in contact with plate cylinders 4 which in turn contact a common blanket cylinder 5 above the common roller 2. A fixed roller 6 is present on each side of the common roller 2 but adjacent the outside wall of the cabinet 1. Tractor feeds 7 are present between the fixed rollers 8 and the common rollers 2. An auxiliary roller 8 is pivotally mounted below each fixed roller 6 adjacent each side of the cabinet, the rollers being located substantially diagonally across the cabinet.

The power drive and control apparatus are housed adjacent the cabinet 1 beneath an arcuate ceiling which defines a dished floor 9 to the printing towers. This enables the continuous stationery to be slackened when required.

In use, a folded stack of continuous stationery to be printed Sb having tractor feed margins is mounted on a table outside the cabinet. The stationery is drawn through the cabinet over a fixed roller 6 and between the common roller 2 and the blanket cylinder 5 for two inks to be supplied. It emerges at the other side of the cabinet and passes over the fixed roller 6 and then below and over the adjacent auxiliary roller 8 and then diagonally across the cabinet to the underside of the opposite auxiliary roller 8. This presents the face of the stationery to the second printing.

The stationery then passes through the cabinet over the adjacent fixed roller 6 between the blanket roller 5 on that side and the common roller 2 to exit from the cabinet to emerge and be folded as the exit stack Sf.

The printing may be done using a number of colours such as yellow, red, blue and black. Because the colour printing is done continuously within compact apparatus and the first colour is not dry when the last colour is applied the colours can be processed to merge and form aesthetically pleasing colour combinations.

The printing may be done using a variety of form sizes of continuous stationery whereby the blanket cylinder may be removed and its timing adjusted via a scale. The invention is not limited to the embodiment shown. The printing means may take a different form and each side of the apparatus may have more than one printing tower. Three colours may be applied, or the number of colours may exceed four.

The auxiliary roller may be mounted in a different way and the inclination may be fixed or variable. The apparatus may be mounted so that the stationery emerges in a vertical plane.

Claims

1. A printing apparatus comprising at least two printing means arranged in side by-side relation, each to apply a separate colour, each printing means being in contact with a common blanket roller, and feed means for passing continuous stationery past the blanket roller to print at least two colours on the stationery.

2. A printing apparatus according to Claim 1, wherein each colour printing means comprises a print tower arranged to provide two colours to the blanket roller.

3. Apparatus according to Claim 1 or Claim 2 wherein the feed means is arranged to tum over the stationery whereby printing takes place on both sides of the stationery.

4. A printing apparatus according to Claim 3, wherein the feed means includes pivotally mounted arms arranged diagonally across the apparatus over which the stationery is passed.

5. A printing apparatus according to any preceding Claim, wherein the floor of the apparatus is dished to provide a space for adjustment of the continuous stationery.

6. A printing apparatus according to any preceding Claim, including means to accommodate a plurality of sizes of continuous stationery.

7. A printing apparatus according to Claim 6 wherein the timing of the apparatus is adjustable.

8. A printing apparatus for continuous stationary comprising a cabinet housing two print towers arranged in side-by-side relation, each tower having a blanket cylinder, a roller extending across the cabinet to provide counter pressure to both blanket cylinders, a fixed roller at each side of the commen roller and adjacent an outer wall of the cabinet and an auxiliary roller beyond the fixed roller on each wall of the cabinet, arranged for pivotal movement with respect thereto.

9. A method of printing colours on continuous stationery comprising passing the stationery past one printing means so as to apply a first colour and then passing the stationery past a second printing means whereby a second colour is applied in addition to the first, before the first colour has dried.