GB2273386A - Magnetic signboard. - Google Patents

Abstract

A magnetic display system comprises (i) a magnetic backing board 2 magnetised with a plurality of parallel pole strips and (ii) magnetic tiles 3 bearing indicia magnetised in parallel pole stripes, such that in use the pole stripes of the board are aligned with the pole strips of the tiles. The tiles may be rectangular with the indicia laminated thereon. By the use of this system, the indicia can be more easily spaced apart to produce an aesthetically pleasing appearance. <IMAGE>

Description

MAGNETIC SIGNBOARD This invention relates to a magnetic signboard and in particular is concerned with signboards in which the lettering or other indicia can be readily changed.

Signboards are often required where it is desired to display a message which requires to be changed or updated from time to time. It is however, difficult to provide a simple system in which the indicia are accurately aligned and attached to a backing board.

GB 1 099 634 (Baermann) describes a magnetic display system in which a backboard is magnetised with parallel pole stripes and symbols i.e. cutouts in the form of letters provided with alternating pole stripes.

In printed matter the space taken up by letters is generally not equal since aesthetically more pleasing results are obtained by using a variable spacing. It is certainly possible to space the symbols of GB 1 099 634 to give an aesthetically pleasing result but it is time consuming to do so.

The invention seeks to overcome or reduce the problems associated with this prior art.

According to one aspect of the invention there is provided a magnetic display system which comprises a magnetic backing board which is magnetised with a plurality of parallel pole stripes and indicia which are held on the backing board by magnetic attraction, the indicia comprising magnetic tiles magnetised in parallel pole stripes aligned with the pole stripes of the backing board and carrying indicia on the faces of the tiles.

Because the indicia are carried on tiles rather than being cut out in the shape of the indicia spacing can be readily achieved. Furthermore to make the symbols of the prior art requires a large number of dies; corresponding to each symbol. In the invention the tiles are polygonal preferably quadrilateral. Other shapes such as triangular may be adapted. As such they are easily cut from stock material.

The edges of the tile abut an adjacent tile thereby generating the desired spacing.

In accordance with the invention it is possible for the user to prepare his own indicia for mounting on the tiles.

The spacing between the pole stripes is not critical but a spacing of about 2 to 5 millimetres is convenient. While the tiles carrying the indicia preferably have the same pole spacing, it is possible to select a pole spacing of one component which is a multiple of the pole spacing of the other component.

The major advantages of providing parallel spaced poles on the backing board and the tiles bearing the indicia is that the tiles automatically align themselves horizontally along the lines of the pole stripes. Thus if a tile is displaced by a vertical distance accidentally or twisted through an angle to the horizontal, the tile will correct its position.

The invention is illustrated by the accompanying sketches in which; Figure 1 is a partial perspective view of the system; Figure 2 is a section through the magnetic backing board and one tile; Figure 3 and 4 show diagrammatically the way in which misalignment is corrected in accordance with the invention.

Referring to the drawings, the signboard comprises a substrate 1, e.g. of blockboard onto which is fixed a magnetic sheet 2 forming the backing board, tiles 3, bearing indicia are removably mounted on the backing board by magnetic attraction.

Both the backing board and the tiles are magnetised in horizontal bands such that each pole strip (e.g. North) is spaced from its corresponding pole strip (e.g. South) by a small regular distance, e.g. 3 mm.

Thus the title can be formed into messages in which adjoining tiles are always aligned in mutually parallel bands. If an individual tile is accidentally displaced the magnetic lines of force will automatically re-align the displaced tile as indicated diagrammatically in Figures 3 and 4.

Both the tiles 3 and the backing sheet 2 are formed from a flexible rubber sheeting in which ferromagnetic material has been incorporated. This may be achieved, e.g. by mixing a magnetic iron oxide with a rubber composition, producing an unvulcanised sheeting by calendaring and then vulcanising the sheeting by heating.

The magnetic pole stripes are introduced by subjecting the sheeting to a strong magnetic field, using one or more suitably shaped magnetising coils and reversing the polarity as the sheeting passes the coil to produce magnetic pole stripes in the sheeting. Typically pole spacing is about 2.5 to 3 mm. One commercial magnetised sheet is available under the trade name Vynon Rubber Magnet 8-CL. Its magnetic and physical properties are as follows: Magnetic Value Residual Flux Br (Gauss) 1900 Property Coercive Force HC (Oersteds) 1570 Max Energy Product DH Max (MGOe) 0.79 Physical Special Gravity (g/cm3) 3.5-3.7 Property Hardness (Shore A) 96 Tensile Strength (Kg/cm2) 80 (MD) 60 (CD) Elongation (%) 50 (MD) 90 (CD) Thicknesses for the magnetic sheet may vary from 0.5 to 1 mm.The magnetised indicia can be produced by laminating a suitable vinyl coating of desired colour over the magnetised rubber sheeting to give the desired base colour, and cutting or printing e.g. by screen printing a desired indicia on the vinyl laminated magnetised sheeting, preferably of a high contrast colour, e.g. reflective white or fluorescent white.

Individual tiles are then obtained by die cutting the laminated sheet. It is also possible to laminate photographs or designs onto the magnetic rubbery sheet.

Photographs can be produced by direct printing onto photo-sensitised plastics film. The resulting photographs or designs can be mounted by magnetic attraction onto the baseboard, together with lettering and/or numerals to illustrate a sales or other message.

The term 'indicia' is used to include all such visual material.

The baseboard is similarly formed from the magnetic sheeting and may be used in a colour matching the base colour of the tiles.

It will be appreciated that the indicia tiles must be cut accurately so that an edge corresponds to the same point on a pole stripe of each tile unless of course subscripts or superscripts are required.

After applying and positioning the indicia tile 3 on the baseboard, the prepared message can be protected with a transparent cover 4 laid over the tiles.

Preferably this has a matt surface to prevent reflection.

The substrate, backing board or sheet and the protective cover may be supported in a frame as described for example in my patent application number 92 094 30.9, see especially Figures 6 to 10.

A slight grey tint to the protective cover will reduce highlights on the edges of the tiles so that the tiles merge into the backing sheet and the letters or other indicia on the tiles stand out. Suitable material for the protective cover include plexiglass XT, a polyacrylate sheet, e.g. perspex or a polycarbonate sheet, e.g. Macrolon.

Claims (5)

CLAIMS:

1. A magnetic display system comprising: i a magnetic backing board magnetised with a plurality of parallel pole strips and ii magnetic tiles bearing indicia magnetised in parallel pole stripes, such that in use the pole stripes of the board are aligned with the pole strips of the tiles.

2. A system as claimed in claim 1 wherein the tiles are polygonal.

3. A system as claimed in claim 2, wherein at least some of the tiles are rectangular.

4. A system as claimed in any one of the preceding claims wherein the indicia are laminated onto the tiles.

5. A magnetic display system substantially as described herein by reference to the Figures.