GB2525699A

GB2525699A - Improvements in laminating machines

Info

Publication number: GB2525699A
Application number: GB1423102.1A
Authority: GB
Inventors: Sebastien De La Hamayde
Original assignee: Vivid Laminating Technologies Ltd
Current assignee: Vivid Laminating Technologies Ltd
Priority date: 2014-01-07
Filing date: 2014-12-23
Publication date: 2015-11-04
Anticipated expiration: 2034-12-23
Also published as: CN104760389A; GB2525699B; GB201400189D0

Abstract

The build-up of static electricity in a roll of film in a laminating machine is obviated by providing an electrically conductive path between the mandrel on which the film is rolled and the frame of the machine. In accordance with the invention the mandrel (11 figure 1) rotates at each of its ends in an electrically conductive plate 17 in contact with a bracket (14 figure 3) of the machine. The plate 17 may be sandwiched between a pair of nonconductive discs 15,18, which serve to hold the plate 17 in position on the bracket.

Description

TITLE

Improvements in laminating machines

DESCRIPTION

This invention relates to an improved laminating machine and in particular such a machine in which provision is made for discharging static electricity developed by a mandrel supporting a roll of film.

In a laminating machine film to be applied to a worlcpiece is drawn from a roll wound onto a mandrel which is supported at either end by brackets of the machine. At each end the mandrel is supported by a disc, which forms a bearing in which the mandrel rotates, the disc in turn being supported by a bracket, For economic reasons each disc is of a non-electrically conductive, plastics material. In such an arrangement the roll of film and its mandrel is electrically isolated from the associated bracket. This leads, in use, to an undesirable build-up of static electricity in the film aiid mandrel which can give a shock to the user of the machine.

A principal object of the present invention is to provide a solution to this problem.

In accordance with the invention there is provided a bearing element for supporting a mandrel rotatably on a bracket, wherein the bearing element comprises an electrically conductive plate having a hole in which the mandrel can rotate and at least one outer face for engagement by the bracket, whereby the plate provides an &ectrically conductive path from the hole to the outer face for the discharge of static electricity from the mandrel to the bracket.

In a preferred embodiment of the invention the plate is sandwiched between a pair of discs, the discs being of a non-electrically conductive material.

The faces of each pair of discs which confront one another may have recesses in which the plate is located.

The plate may be fixed by screws to the respective discs. Alternatively each disc may be fixed by screws to the opposing disc, the screws passing through respective apertures in the plate.

In accordance with the invention there is also provided a laminating machine in which a roll of film on a mandrel is supported at each end of the mandrel by all electrically conductive bracket, wherein an electrically conductive plate in which the mandrel rotates is engaged by the bracket to provide a path from the mandrel to the plate and from the plate to the bracket for the discharge of static electricity from the mandrel to the bracket.

A preferred embodiment of the invention will now be described by way of non-limitative example with reference to the accompanying drawings, in which: Figures 1 and 2 are perspective views respectively from in front and behind of a laminating machine; Figures 3 and 4 are views on an enlarged scale of the assembly at one end of a mandrel carrying a roll of film, respectively in side elevation and in front elevation; Figure 5 is an exploded view of a first embodiment of the assembly which supports one end of a mandrel; and Figure 6 is an exploded view of a second embodiment of the assembly which supports one end of a mandrel.

As is known per se the laminating machine 10 has mandrels 11 and 12 which, in use, will support respective rolls of film which will be drawn onto top and bottom surfaces of a workpiece to laminate the same. In some machines a third film is drawn from the back ol'the machine, The mandrel 13 for this is shown in Figure 2.

Figures 3 and 4 are enlargements of any one of the mandrel bearings "A" of Figures 1 and 2. Each mandrel 11, t2 and 13 is supported at its opposite ends by a bracket 14 of the machine 10. To maintain its alignment the mandrel rotates in a bearing element which abuts a collar 16 on the mandrel.

In accordance with the present invention the bearing element comprises a plate 17 of an electrically conductive material such as steel or another ferrous metal. The plate t7 is sandwiched between a first disc 15 and a second disc 18 which serve to hold the plate 17 in position on the bracket 14. The plate 17 has flat sides 19 and 20 which are in sliding engagement with the sides of a recess 21 in the bracket 14 so that the plate arid bracket are in electrical contact. The mandrel 11 rotates in a central hole 22 in the plate 17 so that the mandrel and the plate are in electrical contact. In this way an electrical pathway is provided between the mandrel 11 and the bracket 14 which will earth static electricity built up by rotation of the film-bearing mandrel.

The first and second discs 15,18 each have a central hole slightly larger than the central hole 22 of the plate 17 so that the only contact between the bearing element and the mandrel II is through the plate L/.

The first and second discs 15,t8 are fixed to the plate 17 that is sandwiched between them. k the embodiment of Figure 4, this is achieved by providing the plate 17 with a pair of threaded bores 23. Each of the first and second discs 15,18 is provided with a non-threaded aperture 24, through which a screw 25 can pass to engage with a respective one of the threaded bores 23 in the plate, thereby fastening the assembly together. Each of the first and second discs 5,l8 comprises on its inner face a shallow recess 26, which provides a seat for locating the plate 17 in order to prevent relative rotation between the respective disc and the plate. The combined depth of the mutually facing shallow recesses 26 is less than the thickness of the plate 17, so that a central part of the each flat sides 9,20 of the plate remains exposed following assembly.

The embodiment of Figure 6 is ihe same as that of Figure 5 excepi For the mariner of fixing the discs 15,18 to the plate 17. In this embodiment, each disc 15,18 is provided with a single aperture 24 as before and, on the opposite side of the central hole, with an inwardly-facing boss 27 that has a central blind bore. The plate 17 is provided with a pair of non-threaded bores 28, which are large enough to receive the respective bosses 27. The discs 15,18 and plate 17 are aligned as shown in Figure 6 then a self-tapping screw 29 is passed through the aperture 24 of each disc to mate with the blind bore in the boss 27 of the opposite disc. This embodiment has two advantages over that of Figure 5: the assembly is stronger because each disc 15,18 is fixed to the opposite disc at two points, instead of each disc being only fixed to the plate t7 at a single point; and it is cheaper to manufacture because the expense of forming threaded bores 23 in the plate 17 can be avoided.

It will be understood that the safety device represented by the present invention can be applied to a laminating machine having any number of film-dispensing mandrels.

Some have only one; others have two or three.

Claims

CLAIMS1. A bearing element for supporting a mandrel rotatably on a bracket, wherein the bearing element comprises an electrically conductive plate having a hole in which the mandrel can rotate and at least one outer face for engagement by the bracket, whereby the plate provides an electrically conductive path from the hole to the outer face for the discharge of static electricity from the mandrel to the bracket.
2. A bearing element as claimed in claim 1, wherein the plate is sandwiched between a pair of discs, the discs being of a non-electrically-conductive material.
3, A bearing element as claimed in claim 2, wherein the faces of each of the pair of discs which confront one another have recesses in which the plate is located.
4. A bearing element as claimed in claim 2 or claim 3, wherein the plate is fixed by screws to the respective discs.
5. A bearing element as claimed in claim 2 or claim 3, wherein each disc is fixed by screws to the opposing disc, the screws passing through respective apertures in the plate.
6. A bearing element as claimed in claim 5, wherein each disc comprises a boss that is received in one of the apertures in the plate, each boss comprising a bore for engagement by a respective one of the screws.
7. A laminating machine in which a roll of film on a mandrel is supported at each end of the mandrel by an electrically conductive brackel, wherein the mandrel is supported rotatably on each bracket by a bearing element as claimed in any preceding claim.
8. A bearing assembly substantially as hereinbefore described and as shown in the accompanying drawings.

9, A laminating machine substantially as hereinbefore described and as shown in the accompanying drawings.