AU699584B2 - Method and assembly for effecting a join in solid surface materials - Google Patents

Description

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AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

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*5 00 0 0 0 00 r eo 9 6 o o« k Name of Applicant: Actual Inventor: Address for Service: Invention Title: CSR LIMITED *Leah edn riTw> Leslie John Irwin H.R. HODGKINSON CO.

Patent Trade Mark Attorneys Level 3, 20 Alfred Street MILSONS POINT NSW 2061 METHOD AND ASSEMBLY FOR EFFECTING A JOIN IN SOLID SURFACE

MATERIALS

0* 0 Details of Associated Provisional Applicatic is: Nos: PM5148 and PM8899 filed on 18 April 1994 and 19 October 1994 The following statement is a full description of this invention, including the best method of performing it known to us: METHOD AND ASSEMBLY FOR EFFECTING A JOIN IN SOLID SURFACE

MATERIALS

The present invention relates to solid surface materials such as are used in kitchens and more particularly relates to a solid surface assembly and to a method for effecting more economic fabrication of solid surfaces.

Solid surface materials are manufactured from plastics material and sold by their manufacturers in slabs or sheet boards. in Australia and elsewhere for example, such materials are marketed under one or more of the following registered trade marks: CORIAN, AZTEQUE, MARBLO, SURELL and HYTEX. To date solid surface materials have not .:"found wide market acceptance and the majority of kitchen benches, and like work surfaces, "are formed from laminate material which is glued or otherwise adhered to some substrates such as particle board. The best known of these laminate materials is that sold under the 15 registered trade mark FORMICA.

In the construction of kitchen benches made of solid surface material, it is necessary for the benches to be fabricated in a factory and transported to the kitchen sie in manageable sized pieces where a final assembly takes place. With kitchen benches formed from laminate material, the various portions of the kitchen bench are clamped together and a distinct join S line is visible between the various portions of the bench. This join line has been tolerated by the customers purchasing such kitchen benches because the installed cost of the kitchen bench is relatively inexpensive.

However, an important selling feature of solid surface materials is that the joins in the kitchen bench when finally installed are to all intents and purposes invisible. This invisibility applies not only to the casual visitor to the kitchen, but to the owner of the kitchen bench. However, this perfection in joinery comes at a substantial cost over and above those kitchens showing a join.

~~YI~glcl It is the substantial difference in installed price which accounts for the lack of market success of the solid surface materials, except in luxury installations. Although part of the cost differential is due to the higher cost of the solid surface material itself, a large part of the cost is attributable to the installation methods hitherto required to install the solid surface material and obtain the invisible join. In particular, hitherto previously the slabs of solid surface material have been edge abutted and glued. This necessitates the workmen waiting for approximately two hours until the glue has taken its initial set, or initially hardened, before the solid surface material is then able to be finished by means of grinding, sanding or polishing machines so that the line of the glue joint is ultimately hidden from view.

An advantage of the pre-ent invention is that consumers can purchase a solid surface material but avoid the high costs associated with supplying that material in one piece as now the consumer can choose a cheaper alternative due to the ability to now join together two slabs of solid surface material on site.

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It is the object of the present invention to increase the market penetration of solid surface materials by the provision of an improved joinery method for use with solid surface materials.

It is another object of the present invention to provide a method for creating a near invisible join in a solid surface material and at the same time reducing the cost of installation of the solid surface material.

In its broadest form the present invention comprises; a method of joining together two slabs of solid surface material to form a bench top; each slab having at least one substantially planar surface which is coplanar with the general plane of the respective slab and an edge surface extending around the slab, the method comprising the steps of: a) shaping at least a portion of the edge surface of each slab so as to form two edge L 3 l-L l- ld I -I surfaces of complementary shape, which, when the edge surfaces are abutted in their intended final positions, resist relative movement between the two edge surfaces in a direction perpendicular to said substantially planar surfaces.

b) locating the two slabs together in their final configuration, wherein abutment of said two complementary shaped edge surfaces ensures that the two planar surfaces of the slabs are located substantially flush and coplanar with one another; and c) fitting a fastening clamp to the underside of the bench top formed by abutment of the complementary shaped edges to permanently clamp the two complementary shaped edge surfaces together forming a substantially invisible joint.

In another broad form of the present invention there is disclosed a method of joining together two slabs of solid surface material for use in constructing kitchen bench tops each having at least one substantially planar surface which is coplanar with the general plane of i. the respective slab, and an edge surface extending around the slab, the method comprising .oo..r the steps of: shaping at least a portion of the edge surface of each slab so as to form two edge surfaces of complementary shape, which, when the edge surfaces are abutted in their intended final relative positions, prevent or resist relative movement between the two edge surfaces in a direction perpendicular to said substantially planar surfaces: e

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b) locating the two slabs together in their final configuration, wherein abutment of said two complementary shaped edge surfaces ensures that the two planar surfaces of the slabs are located substantially flush and coplanar with one another; and c) clamping the two complementary shaped edge surfaces together so as to form a joint between the two slabs which is substantially invisible to the casual observer.

As the two pieces of solid surface material are held together by clamping, the joint can be completely or substantially glueless.

Preferably, the two complementary shaped edge surfaces are profiled surfaces, of substantially constant cross-sectional shape along their respective lengths.

Conveniently, the shaping of the edge profiles is carried out by cutting away material from the two slabs of solid surface material simultaneously and with the same cutting tool. The 15 cutting tool can, for example, be a router.

In that case, the two slabs of solid surface material are preferably held in their intended final relative positions, but slightly spaced apart, during the cutting operation.

Conveniently, the two complementary shaped edge surfaces are clamped together using a resilient clip.

In that case, the clamping is preferably carried out by placing the two slabs of solid surface material together in their intended final relative positions, and then pressing the two slabs of solid surface material down onto the clip until the clip engages with the two slabs of solid surface material so as to clamp them together.

The use of such a method is particularly advantageous in the case of installing kitchen work surfaces formed from slabs of solid surface material, since the installation can be carried out 4 i-r without the need to gain access to the underside of the slabs once the slabs are in their final positions.

In another form the invention comprises a spring clip for use in effecting a join between two abutting slabs of a material such as a solid surface material wherein the clip comprises a planar base portion which terminates at one or both ends in a return portion which is biased towards the planar base portion of the clip.

The invention also provides an assembly comprising two slabs of solir, 4 surface material each having at least one substantially planar surface which is coplanar with the general plane of the slab, and an edge surface extending around the slab, wherein the edge surface of the two slabs are shaped, at least along parts of their respective lengths, so as to be of complementary shape to one another, the complementary shaped edge surfaces preventing or resisting 0 relative movement between the two edge surfaces in a direction perpendicular to said 15 substantially planar surfaces when the edge surfaces are placed together, and ensuring that said substantially planar surfaces lie substantially flush and coplanar with one another when a *9" the edge surfaces of the slabs are placed together, thus enabling the two slabs to be clamped together to form a substantially invisible joint between the two slabs.

Preferably, the two complementary shaped edge surfaces are profiled surfaces, of S"substantially constant cross-sectional shape along their respective lengths.

The assembhlv may further comprise at least one resilient clip for clamping the two slabs together. In that case, each slab is preferably provided with an undercut recess or groove in, or structure on, its underside for engaging with the resilient clip, The resilient clip referred to above is of general applicability to the joining of a wide range of surface materials in addition to solid surface material, and can be used to joints sheets or slabs of other surface materials regardless of whether their edges have been shaped as described above.

I7 4 garna~ Accordingly, a second method aspect, the invention provides a method ofjoining together two sheets of surface material each having a planar upper surface, the method comprising the steps of; a) placing the two sheets side by side in coplanar relationship with one another, and b) clamping two edges of the sheets together using a resilient clip adapted to engage with a recess or groove in, or structure on, the underside of each sheet.

Conveniently, the method involves first placing the two sheets of material together in their intended final relative positions, and then pressing the two sheets of material down onto the clip until the clip engages with the two sheets of material so as to clamp it.. m together.

In accordance with the first aspect of the present invention there is disclosed a method of forming a clamped, substantially glueless joint between two slabs of solid surface material, 15 the joint being substantially invisible to the casual observer and said slabs having planar surfaces which are flush, said method comprising the steps of: too a(i) holding said slabs of solid surface material in their intended co-planar relationship but slightly spaced apart from each other; (ii) cutting a profile for each edge of said slabs to be abutted to form said joint, said #9.9 profiles being complementary and being simultaneously cut with the same cutting ~tool; (iii) locating the profiled slabs in their final position; and (iv) clamping said profiled edges together with said surfaces flush.

Embodiments of the present invention will now be described with reference to the drawings in which: Fig. 1: is a perspective view of a prior art method of joining two portions of kitchen bench formed from laminated material; Fig. 2: is a side elevation of the edge configuration of the bench top of Fig. 1; Fig. 3: is a cross-sectional view taken along the lines I-ll of Fig. 1;

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Fig 4: is a perspective view of a similarly shaped bench top formed from two slabs of solid surface material in accordance with the prior art joining methods; Fig. 5: illustrates the prior art method of forming an edge from solid surface material; Fig. 6: illustrates the prior art method of forming a radiused corner from solid surface material; Figs. 7, 8 and 9 are respectively cross sectional views and a perspective view illustrating the formation of an edge in accordance with one embodiment of the present invention; Fig. 9A: is a view similar to Fig. 9 but illustrates an alternative edge formation technique; Figs 10 and 11 are respectively perspective and cross sectional views corresponding to Figs.

1 and 3 but illustrating the joining method of the preferred embodiment; Fig. 12: illustrates the steps carried out in the fabrication of the bench top portions illustrated in Fig. 13; Figs. 13-16 illustrate alternate edge joining profiles; a aFig 17: is a cross-sectional view through two slabs of said surface material clamped 15 together using a steel spring clip; Fig 18: shows an alternative embodiment of the spring clip of Fig. 17; to: a Fig 19: is a cross-sectional view through two pieces of laminated particle board clamped "together using the spring clip of Fig. 17; S: ,Fig 20: is a plan view of a small, constricted working area which is provided with a work surface; and "a Fig 21: shows an arrangement similar to that shown in figure 17 wherein the edge joining Sprofiles are zig-zag.

The prior art method ofjoining portions of kitchen bench tops formed from laminate covered particle board, is illustrated in Figs. 1 3. The bench top 1 has a generally L-shaped configuration and is formed from two portions 2,3 which are easily able to be transported to the kitchen after having being fabricated away from the kitchen in a factory or like industrial premises. As indicated in Fig. 2, the particle board 4 is covered with two sheets of laminate material. The upper sheet 5 overlaps the upper edge of the edge facing sheet 6 and, as illustrated, the leading edge of the upper sheet 5 is bevelled at 7. This is to prevent chipping i of the surface of the upper sheet 5, however, the result is a strip or stripe of generally unsightly appearance since the interior of the sheet 5 has a different colour from the upper surface of the sheet As illustrated in Figs. 1 and 3, the two portions 2,3 are clamped together by means of a threaded fastener 9 having nuts 10 which are each located within a corresponding circular recess 11 in the underside of the portions 2, 3.

The result of the joining method used in Figs. i and 3 is that although the material of the sheet 5 forming the upper surface of the portions 2, 3 is the same colour, there is a clearly visible and quite distinctjoin line between the two portions 2,3. This visible join line has been tolerated in view of the relatively low cost of the bench top 1.

*In Fig. 4, a bench top 14 having a substantially equivalent shape but being formed in 4*c4 accordance with the prior art methods from solid surface material from two slabs 12 and 13, is illustrated. Firstly the two slabs 12, 13 are positioned in essentially their final positions and glue inserted into what will become the joint 15 between the slabs 12,13. After the glue has been applied the slabs 12,13 ae clamped together and approximately two hours must be 51, wasted while the glue achieves its initial set or hardens. After this time, it is then possible to utilise a router (not illustrated) in order to cut the bench profile 17 which forms the front edge of the bench top 14. Illustrated by means of dotted lines in Fig. 4 is the material removed from the slabs 12, 13 by means of the routing action.

Finally, the bench top 14 is sanded and polished which action makes the joint 15 to all intents and purposes invisible, even to the owner of the kitchen who knows the location of the joint.

In Fig. 5 the creation of a bench profile in accordance with the prior art method is illustrated.

Here a slab 22 has an edge member 21 adhered to the underside thereof in order to provide a sufficient depth of material, again the joint being glued and clamped and no action being taken until sufficient time has elapsed for the glue to have hardened. .4After this time has RK-O MOM N I N' i I npOWN" mm elapsed, the bench profile can be routed or ground so as to remove the material 20 indicated by dotted lines in Fig. 5 and thereby form the desired bench profile.

Similarly, in Fig. 6 the steps necessary to form a profiled corner are illustrated. Here three pieces of solid surface material in the form of slabs 24 and 25 and a ccrner portion 26 are edge abutted, glued and clamped together. Again it is necessary to wait while the adhesive sets. After this time, the corner profile can then be routed so as to remove the material from the corner portion 26 illustrated by dotted lines in Fig. 6.

The present invention provides an economic alternative to the present manner of use of solid surface and provides the consumer with a feasible choice. According to the prior art, where *solid surface materials were used, a solid slab was factory prepared and then transported to 4 44*9*4 0. the site for installation. To prepare unitary slabs of solid surface material is ex-,jnsive and for this reason is not readily embraced by consumers. As an alternative, slabs have been factory 15 prepared in two or more (but usually two) pieces then joined together by gluing on site. The slabs must be held in position by temporary clamps, for instance, until the glue dries. This is labour intensive, time consuming and increases the cost of such installations. For consumers who are not concerned about visibility of ajoin, the method and assembly of the present oo invention brings the use of solid surface materials within the reach of the average consumer 444* as substantial savings can be made over methods which employ single piece solid surface materials or which adopt the prior art on site glue joining methodology. Furthermore, the method has the advantage of providing a near invisible join in the bench top and indeed a neater join than is currently the case when joining such solid materials as granite which shows a pronounced join.

In a first embodiment of the present invention illustrated in Figs. 7-9, a method of forming a desired bench profile is illustrated. Here a stip 41 is routed so as to form a preferred or desired exterior proile 43. This routing or shaping step takes place in advance of any gluing and can therefore be done at slack times and the shaped strips 41 stocked until required. As indicated in Fig. 8, the strip 41 is then glued to the slab 42 which will form the bench top.

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After the glue has dried, only the join between the upper portion of the exterior profile 43 and the upper surface of the slab 42 needs to be finished by sanding or polishing. Since a relatively simple transformation between a horizontal surface and a semi-circular surface is required, this polishing and sanding can be automated with conventional production machinery.

In Fig. 9 an alternate bench profile forming technique is illustrated. Here the previously shaped strip 41A is glued to the lower surface of the slab 42, and then what will become the front edge of the bench is finished to its final shape.

In order to address the cost problems inherent with the prior art joinery methods described above in relation to Fig. 4, in accordance with the preferred embodiment of the present invention the joinery methods illustrated in Figs. 10 and 11 will now be described. As before, 66 the bench top 51 has a generally L-shaped configuration and is formed from two slabs 52,53 15 each of which has an exterior profile 43 formed in accordance with the techniques described in relation to Figs. 7-9 above. Where it is necessary to form rounded corners such as 54, this is done by adhering two strips 41 to a corner and then shaping the corner in conventional 9.* fashion so as to produce the desired result in the form of corners 54 as illustrated in Fig. In Fig. 10, the joint 55 between the slabs 52,53 is entirely glueless and is formed by clamping S* the slabs 52,53 together utilising fasteners 59 as illustrated in Fig. 11. As also illustrated in Fig. 11 underneath each of the slabs 52,53 are glued a number of timber supports 56 which abut the timber frame (not illustrated) of the cupboards (also not illustrated) which are positioned underneath, and support, the bench top 51. Immediately beneath the slabs 52,53 in the vicinity of the intended joint 55 are glued support pieces 57,58. The support pieces 57,58 are preferably formed from the solid surface material itself and therefore have the same co-efficient of thermal expansion as that of the bench top 51, however, the support pieces 57,58 could be formed from plyboard or other material which is less expensive that the solid surface material.

As illustrated in Fig. 12, at the factory and prior to installation, the two slabs 52 and 53 are held in their. intended co-p!anar position but slightly spaced apart in the vicinity of the intended joint 55. Then a router 61 is moved on a generally J-shaped path indicated by the arrow and dotted lines in Fig. 12 in order to cut an edge profiie on the edges 62,63 which will be butted together to form the joint 55. Preferably the edges 62 and 36 are further modified by the provision of slots 64 which are each shaped to receive a disc 65. Since this cutting activity is performed with the slabs 52,53 held with their upper surfaces flush, this p. -cise positioning in the factory can be recreated in the kitchen by means of locating each of the discs 65 in the corresponding slots 64.

As illustrated in Figs 10 and 11, at installation, the slabs 52,53 are edge abutted with each *disc 65 located in its corresponding pair of slots 64 and the fastener 59 is then used to clamp j the two slabs 52,53 together in the same manner as described in Figs. 1 and 3 above.

15 However, because of the treatment given to the edges 62,63 prior to installation, the result of the clamping technique used in Figs, 10-11 is vastly different from that resulting in Figs. 1 S* and 2. In particular, the edges 62 and 63 match each oter perfectly and have been formed with the upper surfaces of the slabs 52 and 53 perfectly flush as able to be set in a factory jig.

As a consequence, this perfect fit is able to be easily recreated in the kitchen with the consequence that the joint 55 is invisible to the casual visitor to the kitchen who is unawa' ;Old of the location of the joint. Furthermore, no expensive sanding or polishing operations are 0 Arequired on site.

The consequence of the use of the methods described in Figs. 7-12 is that the overall cost is substantially reduced.

Turning now to Figs. 13-16, various alternative profiles for the edges 62,63 of Figs 10-12 are illustrated. In Fig. 16 the edges 62,62 are provided with an S-shaped configuration whilst in Fig. 14 an interlocking finger configuration is provided. Fig. 15 illustrates in cross-sectional form a dowel joint, however, Fig. 15 is equally applicable to the situation in which both the

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edges 62 and 63 are cut with a longitudinally exteniding slot and a rectangularjoining merabe r 69 is positioned within the slots. In Fig. 15 also illustrates a joint using a LAMELLO (Registered Trade Mark) biscuit system. In Fig. 16 a V-shaped tongue and groove joint is illustrated. Rather than the V-shaped tongue illustrated, different profiles such as a round or square matching tongue and groove can be used.

Fig 17 shows an alternative way of clamping togethc_ two pieces of solid surfacF material and 82 so as to form an invisible joint 84 therebetween. As described above, the two slabs 82 are provided with complementary shaped profiled edges 86 and 88 respectively, which allow the two slabs 80, 82 to be placed together so as to form an accurately flush upper work surface 90. However, instead of using the fasteners 59, shown in Fig. 11, to clamp the two slabs 80 and 82 together, a steel spring clip 92 is used. The spring clip 92 is formed by bending a rectangular sheet of steel, about 20 cm long and 8 cm wide, to form a flat base portion 91, and two engagement portions 93 at opposite ends thereof The spring clip 92 I 15 engages with two strips or blocks of solid surface material (or other material) 94 and 96 which are glued to the undersides of the two slabs 80 and 82 respectively, adjacent the :w profiled edges 86 and 88 thereof The blocks 94 and 96 are provided with chamfered outer edges 98 and 100 adapted to guide outwardly curved edges 102 and 104 of the spring clip 92 of the blocks 94 and 96 until they engage with respective undercut portions 106 and 108 of 0000 the blocks 94 and 96.

°The arrangement shown in Fig. 17 is particularly advantageous when it is necessary to install work surfaces in confined spaces. Figure 20 shows the two slabs of solid surface material and 82 fitted together to form a work surface 110 within a constricted working area defined by a number of walls i 16. In order to clamp the two slabs 80 and 82 together, one or more spring clips 92 are placed, beneath the joint 84, on the timber frames of cupboards (not shown) which are located below 'he work surfaces 110. The two slabs 80 and 82 are then simply pressed down onto the spring clips 92 until the spring clips 92 snap into engagement around the two blocks 94 and 96 to clamp the two slabs 80 and 82 together.

It will be appreciated that this is considerably easier than having to manually tighten a fastener on the underside of the work surface 110. In fact, the use of the spring clips 92 provides a saving in time of about half an hour per joint. A sealant or adhesive can be used between the two edges 86 and 88 of the slabs if required. Furthermore, the spring clip 92 can be removed by simply lifting oile of the slabs up with respect to the other. Of course, if an adhesive is used, this must be done before the adhesive sets.

The arrangement shown in Fig. 18 differs from that of Fig. 17 in that the block 96 on the underside of the slab 82 is removed, and a modified spring clip 112 is used. The modified spring clip 112 includes a flat portion 114, which replaces one of the engagement portions 93, and which is used to the underside ,f the slab 82. In use, the slab 82 is first placed in position and the slab 80 is then pressed down until tile upper surfaces of the slabs 80 and 82 are flush and the block 94 snaps into the spring clip 112.

15 The thickness of the slabs 80 and 82 shown in Figs. 17 and 18 is about 13 mm, and the (vertical) thickness of the block 94 and 96 is about 19 mm. Typically, the edge surfaces 86 and 88 of the slabs are formed with three or four waves, which extend along the whole length u of the edges. In Fig. 17, the top and bottom corner edges 126 and 128 of the edge surface 86 are pointed, and protrude outwardly, whereas the corresponding corner edges of the edge surface 88 are rounded. If it is necessary to slide the two edge surfaces 86 and 88 across one 9" another, for example if the space is restricted, it is preferable to first position the slab 82 and to then lower the slab 80 until the joint 84 is flush. The reason is that any damage to the lower corner edge 128 caused by the movement of the edge surfaces 86 and 88 against one another will not be visible in the finished product. In order to facilitate the movement of the edge surface 86 across the edge surface 88, the material forming the lower corner edge 128 can be removed before installation so that the lower corner edge 128 has a rounded profile as shown at 130.

The profiled edge surfaces 86 and 88 can be of any complet-ntary shapes. An example of an alter native to the undulating shape of Figures 17 and 18 is shown in Figure 21. Figure 21 shows the two edge surfaces 86 and 88 each having two inclined surfaces 132 separated by a short, central horizontal surface 134.

Fig. 19 illustrates the use of the spring clip 92 to clamp together two particle boards 118 having upper surfaces formed from laminate material 120. Two strips 122 and 124 are glued to the undersides of the particle boards 188. The strips 122 and 124 have the same crosssectional shape as the blocks 94 and 96 shown in Fig. 17.

The foregoing 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 of the present invention. For example, although no glue is used in the joint 55, if desired a small amount of mastic or silicon rubber can be used in the joint 55 in order to provide a water .proofing seal.

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Claims (14)

1. A method of joining together two slabs of solid surface material to form a bench top; each slab having at least one substantially planar surface which is coplanar with the general plane of the respective slab and an edge surface extending around the slab, the method comprising the steps of: a) shaping at least a portion of the edge surface of each slab so as to form two edge surfaces of complementary shape, which, when the edge surfaces are abutted in their intended final positions, resist relative movement between the two edge surfaces in a direction perpendicular to said substantially planar surfaces. b) locating the two slabs together in their final configuration, wherein abutment of said two complementary shaped edge surfaces ensures that the two planar surfaces of the slabs are located substantially flush and coplanar with one another; and c) fitting a fastening clamp to the underside of the bench top formed by abutment of the complementary shaped edges to permanently clamp the two complementary shaped edge surfaces together forming a substantially invisible joint. i

2. A method according to claim 1 comprising the additional step of cutting a profile in each edge of said slabs to be abutted to form said joint, said profiles being complementary 4i and being simritaneously cut with the same cutting tool.

3. A method according to claim 2 comprising the step, prior to clamping the two complementary shaped edge surfaces together, of attaching supports to the underside of the solid surface material and which abut the frame of a cupboard or like structure.

4. A method according to claim 5 wherein the fastening clamp comprises a threaded bolt which receives a nut wherein the bolt is rotated to urge the edge surfaces of the slabs into abutment. A method according to claim 4 comprising the step of clamping the two complementary shaped edge surfaces together by means of a clip having at least one return portion which engages an undercut surface on a block attached to the solid surface material.

6. An assembly for effecting joining of two slabs of a solid surface material according to the method hereinbefore described in claim 1 wherein each slab has at least one Ssubstantially planar surface which is coplanar with the general plane of the respective slab i iM and an edge surface extending around the slab, and a clamp for permanently clamping two complementary shaped edge surfaces together so as to form a joint between the two slabs which is substantially invisible, wherein the edge surface of the two slabs are shaped, at least along part of their respective lengths so as to be of complementary shape to one another, the complementary shaped edge surfaces preventing or resisting relative movement between the two edge surfaces in a direction perpendicular to said substantially planar surfaces when the edge surfaces are placed together and ensuring that said substantially planar surfaces lie substantially flush and coplanar with one another when the edge surfaces of the slabs are placed together.

7. An assembly according to claim 6 wherein the clamp engages at least one block affixed to the underside of each slab to be jointed and spans between each block.

8. An assembly according to claim 7 wherein the clamp comprises a nut and bolt assembly wherein the head of the bolt and the nut are accessible via respective recesses in :4 said blocks for the purpose of tightening and loosening. A.4.. t oo 9. An assembly according to claim 8 wherein there are at least two nut and bolt assemblies every 100 150 mm of join length.

10. An assembly according to claim 9 wherein the recesses formed in the blocks are circular and are sized to enable either the head of said bolt or said nut to be rotated. oo. 11. An assembly according to claim 10 wherein the blocks are in opposing relationship to each other and are spaced apart by a length of solid surface material.

12. An assembly according to claim 7 wherein the clamp comprises a steel spring clip having a planar base portion and at one or both end/s a return portion which engages a So surface on one or both of said blocks. •13. An assembly according to claim 12 wherein the surface on the blocks is undercut to enable the return portion when the clip is in situ to spring back towards the centre of the clip.

14. An assembly according to claim 13 wherein the iwo slabs are pressed down onto the clips after the clips are mounted on the frame of a cupboard beneath the solid surface material. 4 J16 An assembly according to claim 11 or 14 wherein the edge surfaces of the respective slabs each have a complementary zig-zag profile.

16. An assembly according to claim 15 wherein the edge surfaces of the respective slabs each have a complementary wave form profile.

17. An assembly according to claim 16 wherein the clip comprises a planar base portion which terminates at one or both ends in a return portion which is biased towards the planar base portion of the clip wherein said retur pL t'i:n/s engage/s a structure on one or both of the two slabs to effect said join.

18. A method as hereinbefore described and with reference to figures 7 through 21 of the accompanying drawings.

19. An assembly as hereinbefore described and with reference to figures 7 through 21 of the accompanying drawings. DATED this 22 nd day of October 1998 H LESLIE JOHN IRWIN By: I A o His Patent Attorneys *I LELI JHNIRI By: ABSTRACT A method of joining together two slabs of solid surface material, each having at least one substantially planar surface which is coplanar with the general plane of the respective slab and an edge surface extending around the slab, the method comprising the steps of a) shaping at least a portion of the edge surface of each alb so as to form two edge surfaces of complementary shape, whicf, when the edge surfaces are abutted in their intended final positions, prevent to resist relative movement between the two edge surfaces in a direction perpendicular to said substantially planar surfaces. b) locating the two slabs together in their final configuration, wherein abutment of said two complementary shaped edge surfaces ensures that the two planar surfaces of the slabs are located substantially flush and coplanar with one another; and c) clamping the two complementary shaped edge surfaces together so as to form a joint between the two slabs which is substantially invisible to the casual observer. *soot: .4 C. Si