Background of the Invention PVC materials have been used in various ways as sign materials. The PVC material is flexible, easily cut, cleanly cut, attractive in appearance and available in many colours, and is suitable to form a part of composite, layered signage material.

Examples of usage of PVC sheet material for signage can be found in W092/17869 (to Brady Coated Products) and US5112423 (Liebe).

A relatively simple layered technique involves PVC sheet initially applied to a backing layer as generally illustrated in Fig 1. Indicia or lettering shapes are cut into the vinyl layer and residual PVC material is lifted from the backing layer (termed "weeding") leaving the lettering shapes only on the backing layer.

An application tape or layer is then applied over the top of the backing layer and residual indicia so as to sandwich the residual indicia therebetween. This procedure is termed "laminating" and is carried out in such a way as to allow the backing layer subsequently to be peeled from the residual indicia leaving the upper face of the residual indicia adhered to the underside of the application tape or layer.

This allows subsequent placement of the underside of the residual indicia against a surface to which the residual indicia is to be applied as a sign.

The weeding operation and the laminating operation requires careful alignment of layers both during formation and during removal, to or from one another. Such alignment has not always been easy by manual methods, nor always by automated methods. Often the methods involved require a significant amount of room to allow the operations to take place.

It is an objection of the present invention to address or ameliorate one or more of the abovementioned disadvantages and, in one particular form, to combine weeding and laminating operations into a single operation.

Brief Description of the Invention Accordingly, in one broad form of the invention there is provided, in combination a sign weeder and laminator for a sign system of the type where sign material comprises a base layer adhered to a sign layer as a laminate; said sign layer adapted to have indicia separation lines cut into the sign material which define residual indicia which can be lifted clear of the base layer by application of an application layer to a top surface of said residual indicia; said weeder and laminator including weeding means adapted to remove surplus sign material from said sign layer in combination with a laminator adapted to apply an application layer to said base layer and said top surface of said residual indicia.

In one preferred form, said sign material passes directly from said weeder to said laminator.

In an alternative preferred form, said sign material passes via guide means from said weeder to said laminator.

Preferably, said guide means comprises a profiled aperture.

Preferably, said profiled aperture is in the form of a reverse S curve.

Preferably, said guide means further includes opposed rollers having a nip therebetween through which said base material and said application layer are passed in juxtaposed relationship.

Preferably, said nip is located on an exit side of said profiled aperture.

In a further broad form of the invention there is provided a laminator for a sign system of the type where sign material comprises a base layer adhered to a sign layer as a laminate; said sign layer adapted to have indicia separation lines cut into the sign material which define residual indicia which can be lifted clear of the base layer by application of an application layer to a top surface of said residual indicia; said laminator comprising guide means in combination with lamination means whereby said base layer is fed through said guide means so as to then combine with said application layer for lamination by said lamination means so as to form said laminate.

Preferably, said lamination means includes opposed rollers having a nip defined therebetween for urging of said base layer against said application layer so

as to form said laminate.

Preferably, said lamination means further includes a vacuum roller adapted to hold said application layer against a surface thereof by means of a vacuum applied through apertures in said vacuum roller.

Preferably, said lamination means further includes a pressure roller adapted to define a nip between said pressure roller and said vacuum roller through which said base layer and said application layer pass in planar, juxtaposed relationship to said pressure rollers.

Preferably, said lamination means further includes slack inducing means interposed between a source of said application layer and said vacuum roller.

Preferably, said slack inducing means comprises a flap adapted to pivot between a loading position and an operating position whereby the path length of said application layer between said application layer source and said vacuum roller is greater in said loading position than said path length when said flap is in said operating position.

Preferably, said lamination means further includes a guide bar located across an exit zone from said application layer source.

Preferably, said application layer source is pivotable between a loading position and an operating position.

In a further broad form of the invention there is provided a guide system for planar, flexible material; said planar, flexible material adapted for subsequent lamination with other planar, flexible material; said guide system including stressing means adapted to minimize distortion in a laminate made from said planar, flexible material.

Preferably, said stressing means comprises an arcuate guide or aperture adapted to form said planar, flexible material into a shallow arc dynamically as it moves through said guide system.

More preferably, said stressing means forms said planar, flexible material into a reverse S curve dynamically as it moves through said system.

In yet a further broad form of the invention there is provided a method of stressing a planar, flexible material comprising inducing at least a first shallow arc

dynamically in a moving portion of said planar, flexible material.

Preferably, said method further includes inducing a second, reverse shallow arc immediately after said first arc in said planar, flexible material whereby said material dynamically forms a reverse S curve during linear movement of said planar, flexible material.

Brief Description of the Drawings Embodiments of the invention will now be described with reference to the accompanying drawings wherein:- Fig 1. illustrates a vinyl sign layer attached to a backing layer, Fig 2. illustrates the sign after waste vinyl material has been removed leaving residual lettering or indicia, Fig 3. illustrates the residual lettering applied to an application tape ready for application to a signage surface, Fig 4. is a perspective, partially cut away view of a combined weeding and laminating system according to a first embodiment of the invention, Fig 5. is a side section view of the system of Fig 4 in a loading position, Fig 6. is a side section view of the system of Fig 4 with signage material and application tape or layer loaded ready to commence a combined weeding and laminating operation, Fig 7. is a side section view of the system of Fig 4 illustrating the path of signage material and application tape or layer during a combined weeding and laminating operation and Fig 8 A-E illustrates steps in a preferred alternative method of preparing a leading edge of the sign laminate of Fig 4 for operation.

Detailed of Description of Preferred Embodiments A combined sign weeding and laminating system 10 according to a first embodiment of the invention is illustrated in Fig 4 in perspective, partial cut away view. The system 10 is for use with layered signage systems of the type illustrated in Figs 1, 2 and 3. As discussed in the introductory portion of this specification these layered signage systems comprise a sign layer 11, in this instance comprised of a PVC material releasably adhered to a backing layer 12, in this instance

comprising a waxed paper. The outline of letters and other shapes intended to comprise the indicia of a sign are cut, usually by automated means known in the industry, in and only in the sign layer 11 so as to form, in this instance, the letters TOP with an underline. Waste sign layer 13 is then peeled from the vacuum layer 12 as illustrated in Fig 1 so as to leave residual indicia 14 only still adhered to backing layer 12 as illustrated in Fig 2, in this instance, comprising the letters TOP and an underline. With reference to Fig 3 an application layer 15 is applied to the top surface 16 of residual indicia 14 so as to allow subsequent peeling of application layer 15 (together with residual indicia 14 attached) from backing layer 12. The application layer 15 maintains the relative position of the residual indicia 14 during application of rear surface 17 of the residual indicia 14 to a display surface (not shown) following which the application layer 15 is peeled from the top surface 16 of the residual indicia 14 so as to leave the residual indicia 14 attached to the display surface in the form of a sign.

With reference to Fig 4 the combined sign weeding and laminating system 10 suitable for use with the layered signage system of the type described with reference to Figs 1, 2 and 3 comprises three main sub-systems: a weeding sub- system 18, a laminating sub-system 19 and a guide sub-system 20. The guide sub-system 20 is located between the weeding sub-system 18 and the laminating sub-system 19.

Weeding sub-system 18, with particular reference to Fig 4, comprises a trough-like holder 21 for holding a roll of sign laminate 22. The sign laminate 22 comprises a laminate of sign layer 11 and backing layer 12 as generally illustrated in Fig 1 with the outline cuts for the residual indicia 14 already made therein by other means (not shown) and prior to placement in the holder 21.

The sign laminate is fed between sign laminate feed rollers 23 and adjacent a lower face of de-laminating plate 24.

Sign layer 11 is peeled from the backing layer 12 at leading edge 25 of the laminating plate 24 and passed back over the top of the de-laminating plate and taken up in rolled form on waste vinyl takeup roller 26. As seen in Fig 5 the waste vinyl takeup roller 26 comprises elongate bars 27, 28 having bite 29 defined

therebetween which acts to hold a leading edge of the sign layer 11 in a positive manner whereby sufficient clamping force is applied to permit takeup of the sign layer 11 as the bars 27, 28 comprising the takeup roller 26 rotate.

The de-laminating plate 24 is mounted for rotation between an operating position and a loading position about hinge 30 located along rear edge 31. The de- laminating plate 24 can be moved between the two positions by de-laminating plate handle 32.

It will be observed that a first one of the opposed sign laminate feed rollers 23 is located on and rotatably supported by the de-laminating plate 24 and consequently moves with the de-laminating plate from its operating to its loading position thereby opening up sufficient clearance between the feed rollers 23 to permit easy threading of a leading edge of the sign laminate 22 when in a loading position as best illustrated in Fig 5.

Separation of the sign layer 11 from the backing layer 12 occurs along the edge 25 as the sign layer 11 is pulled by rotation of waste vinyl takeup roller 26.

The backing layer 12 with residual indicia 14 passes along guide plate 33 to the guide sub-system 20 and thence to the laminating sub-system 19.

The guide sub-system 20 includes a profiled extension 34 of guide plate 33.

In this instance profiled extension 34 comprises a reverse S curve as generally illustrated in Fig 5. The guide sub-system 20 further comprises a guide cover 35 which includes a correspondingly profiled cover plate 36, again best seen in Fig 5.

When the guide cover 35 is in an operating position the profiled cover plate 36 lays co-extensive with profiled extension 34 so as to define a profiled aperture in the form of a reverse S curve adapted to receive therethrough backing layer 12 with residual indicia 14 thereon. The height of the aperture 37 is such that the backing layer 12 with indicia 14 can slidingly pass therethrough but is forced to conform to the reverse S curve profile of the profiled aperture 37 as it passes through the guide sub-system 20.

Also included in guide cover 35 is vacuum roller guide cover 28 and backing layer detection limit switch 39.

The limit switch 39 acts to sense the presence of the backing layer 12 at the

exit from profiled aperture 37, as best seen in Fig 6. It is utilized by the control system, for example to perform automated feed of a leading edge of the backing layer and to cease feed operation upon detection of absence of backing layer 12.

The guide cover 35 is rotatable between an operating position and an open position about hinge 40 as best seen in Figs 5 and 6. The open position is utilised to gain access for correction of jams or misfeeds.

Guide sub-system 20 acts to ensure correct alignment is maintained of the backing layer 12 with residual indicia 14 as it is passed from the weeding sub- system 18 to the laminating sub-system 19. In addition this sub-system works to minimize or eliminate wrinkling, distortion and/or air bubbles during the lamination process carried out by the laminating sub-system 19.

It is postulated that the reverse or double curves of the profiled aperture 37 stiffen the backing layer 12 and residual indicia 14 sufficient to pass through laminating rollers and the like so as to minimize or eliminate wrinkling or distortion in the resultant laminate 47.

The laminating sub-system 19 comprises pressure roller 41 and vacuum roller 42 together with laminating pressure rollers 45,46.

The pressure roller 41 is rotatably mounted so as to apply sufficient pressure via nip 43 to pull both backing layer 12 (with residual indicia 14 attached) and application layer 15 through the nip 43 and into nip 44 of laminating pressure rollers 45, 46. The laminating pressure rollers apply sufficient pressure at nip 44 to cause releasable adhesion of the top surface 16 of residual indica 14 to the application layer 15 so as to form a laminate 47 of the type illustrated in Fig 3 which is fed via guide path 48 and guide roller assemblies 49, 50 to laminate bin 51.

Laminating sub-system 19 further includes a support bracket 52 adapted to hold the axle 53 for rotation. Axle 53 has wound thereon a supply of application layer 15 which passes over guide bar 54 and around leading edge 55 of de- tensioning flap 56 and thence to vacuum engagement of the surface of vacuum roller 42. Vacuum engagement is performed by a vacuum applied through holes located uniformly on the surface of vacuum roller 42 supplied by an air vacuum

source (not shown).

A vacuum cover 57 shields the non working portions of the surface of the vacuum roller 42 against loss of vacuum across this region.

The de-tensioning flap 56 is movable from a loading position (shown in Fig 5 and Fig 6) to an operating position (shown in Fig 7) by rotation of leading edge 55 about hinge 58.

In its loading position leading edge 55 lengthens the path of application layer 15 between guide bar 54 and the vacuum roller 42. This path is shortened when leading edge 55 pivots to the operating position of Fig 7 thereby providing initial slack supply of the application layer 15 to the vacuum roller 42. The length of slack is sufficient to allow the vacuum roller 42 to feed the slack by virtual of the torque supplied by the vacuum of the vacuum roller 42 so that the application 15 engages with the laminating pressure rollers 45, 46. The nip 44 of these rollers can provide sufficient pulling force to pull the application layer 15 from the roll 59.

In use, a user of the combined sign weeding and laminating system 10 will first move de-laminating plate 24 to its load position by handle 32. The user will then load a roll of sign laminate 22 in holder 21 and feed a leading portion of sign layer 11 around leading edge 35 and into the nip of bars 27, 28 of take-up roll 26.

The backing layer separated from the sign layer 11 is laid upon guide plate 33 and over profiled extension 34. A roll of application layer 15 is mounted via axle 53 upon support bracket 52 in its load position (pivoted forward about pivot 60). A leading edge of the application layer is then fed around the guide bar 54, around leading edge 55 of de-tensioning flap 56 and onto the surface of the vacuum roller 42 where the vacuum holds the application layer leading edge in place. Slots in the vacuum roller (not shown) allow a clean leading edge cut to be made in the application layer 15.

The operator then pivots support bracket 52 to its operating position about pivot 60. De-laminating plate 24 is pivoted to its operating position by operation of handle 32. A belt drive system is then engaged to cause rotation of pressure roller 41, vacuum roller 42, laminating rollers 45, 46, sign laminate feed rollers 23, waste vinyl takeup roll 26 and guide roller assemblies 49, 50. At the same time

de-tensioning flap 56 is rotated by the control system from its loading position to its operating position thereby providing slack in the application layer 15 sufficient to allow a leading edge of the application layer to be taken up to the nip 44 of laminating pressure rollers 45, 46.

The three sub-systems 18, 19, 20 then work together whereby weeding of the sign laminate 22 is performed by weeding sub-system 18, laminating of the backing layer 12 to the application layer 15 with residual indica 14 located therebetween so as to form a laminate 47 via laminating pressure rollers 45, 46 which is then fed into bin 51. The volume of the laminate bin 51 can be expanded by rotation of lid 61 about pivot 62 and/or pivoting of the bin body about pivot 63.

The guide sub-system 20 ensures positive feeding between the two sub-systems and assists, to minimize wrinkling of the resultant laminate 47.

A preferred alternative arrangement for preparing a leading edge of the sign laminate 22 for operation of the system 10 is illustrated in Fig 8 . With delaminating plate 24 in its load position a leading edge 64 of laminate 22 having the structure illustrated in Fig 8A is pulled onto guide plate 33 and a cut is made in backing layer 12 to the full depth of the backing layer 12 and no further and for the full width of the leading edge 64 of sign laminate 22. Cut 65 is illustrated in illustrated in cross section in Fig 8B and can be located , for example , a distance D in from front edge 66 where D can be of the order of 50mm. The front edge portion 67 is then bent back as illustrated in Fig 8 C and clipped by clips 68 to the lower one of sign laminate feed roller 23, for convenience. Thus exposed front edge portion 67 of the backing layer 12 is peeled away from sign layer 11. A piece of lead in paper 69 is placed on guide plate 33 with one edge almost in abutment with the cut 65 as illustrated in Fig 8 C. The front edge portion 67 of sign layer 11 is then unclipped from clips 68 and applied to the top surface of lead in paper 69 as illustrated in Fig 8 D.

The leading edge 70 of the lead in paper 69 is then fed into nip 29 so as t act as a lead in for waste vinyl takeup roller 26 as illustrated in Fig 8 E.

The system 10 is then caused to operate so that takeup roller 26 takes up the lead in paper 69 so as to cause a weeding operation to commence. The lead in

paper 69, surplus sign layer 11 follows onto takeup roller 26, but only after at least 1 wrap of lead in paper 69 in circles takeup roller 26, thereby to prevent adhesive on the sign layer 11 coming into direct contact with the waste vinyl takeup roller 26.

At the same time backing layer 12 with residual indicia 14 advances along guide plate 33, through profiled aperture 37 of the guide sub-system 20. Advance is at a rate which allows an operator to manually remove extraneous sign layer material weeded by the action of the de-laminating plate 23.

Advance ceases when backing layer 12 comes into contact with switch 39.

At this time application layer 15 is pulled through and attached by vacuum to vacuum roller 42 as previously described.

An operator then re-initiates operation of system 10 whereby both application layer 15 and backing layer 12 advance together through the laminating sub-system 19, also as previously described. As previously described, at time of initial advance the de-tensioning flap 56 is moved to its operating position, thereby releasing the necessary slack in application layer 1 so as to ensure vacuum roller 42 can provide the necessary advance of application layer 15.

Operation of system 10 ceases when switch 39 detects loss (end) of backing layer 12.

The above describes only some embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope and spirit of the present invention.

For example the sub-systems 18,19,20 can be used independently to advantage in other systems for processing sign materials of the type illustrated in Figs 1, 2 and 3.

Industrial Applicability Embodiments of the invention can be applied in the sign industry and more particularly the PVC or vinyl sign industry so as to quickly, conveniently and in a minimal space both weed and laminate these and related types of sign materials.