DE LA HAMAYDE, Sebastien (The Innovation Centre, Oxford Street, Leicester LE1 5XY, GB)
CLAIMS:
1. A separator unit (14) for a laminating machine (12), the unit having input and output ends, characterised in that in use the output end is spaced vertically below the input end.
2. A separator unit as claimed in claim 1, characterised in that the unit (14) has at least one internal roller (16) near to said input end to change the direction of a laminated strip (21) entering said input end horizontally and at least one pair of internal rollers (17,18) near to said output end, said pair of rollers (17,18) rotating slightly faster than said at least one roller (16) whereby the laminated strip is tensioned.
3. A separator unit as claimed in claim 2 and comprising a second pair of internal rollers (19,20) upstream of said one pair of rollers (17,18), one (19) of said second pair of rollers rotating about an axis which is not orthogonal to the direction of movement of the strip (21) thereby to tear the latter along lines of weakness .
4. A separator unit as claimed in claim 3, characterised in that said at least one pair of rollers (17,18) is rotated slightly faster than said second pair of rollers (19,20).
5. A separator unit as claimed in any one of the preceding claims, characterised in that the unit (14) has one or more hooks (15) in the region of its upper end for suspending the unit (14) from a laminating machine (12). |
"IMPROVEMENTS IN LAMINATING MACHINES"
This invention relates to improvements in laminating machines and more particularly to an improved separator unit for a laminating machine.
In a laminating machine the item to be laminated, usually a paper sheet, is pressed into contact with a plastics material which is then heated. Heating the plastics material renders it transparent and at the same time welds it to the paper sheet to provide a protective coating.
In single-sided laminating machines paper sheets are fed as a continuous strip into the laminator jointly with a continuous strip of the plastics material drawn down from a roll above the laminator. The paper strip has transverse lines of perforations and after emergence from the laminator the laminated strip passes to a separator where an oblique roller is used to tear the strip along the lines of perforations to provide individual sheets, such as individual posters.
A conventional single-sided laminating machine therefore comprises a feed unit, the laminator itself and a separator unit, all generally horizontal. Such machines take up a great deal of space. Also as the laminated strip passes over the separator unit measures must be taken to ensure that it remains flat. A conveyor belt or the like is used to move the laminated strip and presser elements must be positioned above the conveyor to hold the laminated strip flat on the conveyor.
A principal object of the present invention is to improve upon known laminating machines.
In accordance with the present invention there is provided a separator unit for a laminating machine, the unit having input and output ends, in use the output end being spaced vertically below the input end.
Preferably the unit has at least one internal roller near to said input end to change the direction of a laminated strip entering said input end horizontally and at least one pair of internal rollers near to said output end, said pair of rollers rotating slightly faster than said at least one roller whereby the laminated strip is tensioned.
Preferably a second pair of internal rollers is provided upstream of said one pair of rollers, one of said second pair of rollers rotating about an axis which is not orthogonal to the direction of movement of the sheet thereby to tear the latter along lines of weakness.
Preferably said at least one pair of rollers is rotated slightly faster than said second pair of rollers.
The unit may have one or more hooks in the region of its upper end for suspending the unit from a laminating machine.
A preferred embodiment of the present invention will now be described by way of non- limitative example with reference to the accompanying drawings, in which:
Figure 1 is a perspective view of a laminating machine fitted with a separator unit in accordance with the present invention, and
Figure 2 is a sectional elevation on a larger scale of the separator unit of Figure 1.
A single-sided laminating machine 10 has a horizontal feeder unit 11 aligned with the "nip" of a laminator unit 12. A continuous strip of paper bearing, for example, multiple images of a poster, is fed by the feeder unit 11 into the nip of the laminator unit 12 jointly with a continuous strip of a laminating plastics material drawn down from a roll 13 above the laminator unit. Within the laminator unit 12 the strips of paper and plastics material are pressed together and heated so that the plastics material becomes transparent and is welded to the paper.
In accordance with the present invention the laminated strip of paper passes from the laminator unit 12 to a vertical separator unit 14 suspended by hooks 15 on the output side of the laminating unit 13. Near to the input end of the separator unit 14 is a roller 16 about which the direction of the laminated strip 17 changes from the approximately horizontal to the vertical. Nearer to the bottom or output end of the separator unit 14 is a pair of cooperating rollers 18 and upstream of them a second pair 19, one of which 20 rotates about an axis which is slightly offset from the orthogonal with respect to the direction of movement of the laminated strip 17. The laminated strip 17 has transverse lines of perforations separating the individual images printed thereon. The slight "skewing" of the roller 20 is sufficient to tear the strip along each line of perforations. Thereafter the rollers 18 move the torn off sheets out of the separator unit in a straight line.
Because the descending laminated strip 17 is influenced by gravity it is unnecessary to use an endless conveyor to move it. Moreover it is found that if the rollers 19 rotate slightly faster than the roller 16 and the rollers 18 rotate slightly faster than the rollers 20 the laminated strip 17 is kept under tension such that additional measures to keep it flat are unnecessary.
One of the principal advantages of the invention is that a laminating machine equipped with a vertical separator unit will occupy much less space than one with a horizontal separator unit, space being at a premium in modern offices.