It is known to construct a solid wall using bricks and mortar. The bricks are typically substantially cuboid in shape, with a prism-shaped recess in the two largest faces, which lie opposite one another and which are also the top and bottom faces, for receiving mortar. The bricks can be considered also to have front and rear faces which form the main external surfaces of the wall, and two side faces, which are the smallest faces. Such a wall is constructed in a layered manner, the first layer being created by connecting bricks at their side faces with a layer of mortar. The second layer is added by spreading mortar on the top faces of the first layer and the bottom faces of the bricks to be used for forming the second layer, and, typically, placing the second layer bricks on the top surface of the first layer bricks such that their side faces align with the vertical centrelines of the front and rear faces of the first layer bricks. The third layer can be added in a similar manner, such that the third layer bricks are in alignment with the first layer bricks. The fourth layer is added in a similar manner, such that the fourth layer bricks are in alignment with the second layer bricks. Subsequent layers can be added so as to continue this alignment pattern. Variations on this alignment pattern may be used.

This type of wall is most suitable for permanent buildings, such as houses and offices, or other places where a very strong and permanent wall is required. One reason for this is that it is relatively time-consuming and expensive to construct such a wall. This is firstly because the bricks must be manufactured from clay by a process which includes baking. It is of course possible to buy them ready-made but the cost is dictated by the manufacturing process. Secondly, mortar must be mixed. This mixture rapidly deteriorates in air, therefore it must either be used quickly or kept in motion, by, for example, a cement mixer. This requirement, together with the difficulty of accurately aligning the bricks, makes it awkward for unskilled people to construct a wall themselves.

Another reason for using a brick and mortar wall as a permanent structure is that once the mortar has set it is very difficult to de-construct the wall, especially if the bricks are to be kept intact for re-use. A further reason is that a brick wall is fairly heavy and therefore requires foundations in order to be safely stable.

If a less permanent structure is required, or a permanent structure is to be constructed in a situation where it would be difficult to provide foundations, one known solution is to use a wooden fence. Wooden fences can be constructed in a variety of styles, but in general they are constructed from long, thin sections of wood which are held together by nails or the like. This tends to make them cheaper than brick walls, and therefore suitable for applications such as garden sheds or fencing between gardens. However, they are much less sturdy than brick walls. Secondly, they are not easy to construct, since the sections of wood must be correctly aligned and the nails or other fixings applied in whilst retaining the correct alignment. Thirdly, de-construction is not particularly easy, since it would involve removal of the nails or other fixings, which may well have begun to rust by that time.

There is therefore a need for a wall which can be easily and cheaply constructed in a variety of locations. Ideally such a wall would be stronger than a wooden fence, and capable of being de-constructed if required. This would be useful for non-professional builders who wish to construct walls, or structures comprising walls, themselves, for example in their gardens. Preferably, it would be possible to buy ready-made components for constructing such a wall.

It has been proposed to use a wooden dowel system to fix together wooden blocks. Known systems use simple cylindrical dowels and many gadgets exist in the marketplace for positioning and determining the depth of holes to receive the dowels. Joints created by using such wooden dowels have to be clamped and glued to form a permanent joint. It would therefore be desirable to provide a hidden dowelling system that does not need other types of fixing such as glue.

Ideally, such a system would be capable of being manufactured in volume at a reasonable price. It should also be capable of being constructed using few tools and not require professional skill to construct. There is also a need for a system to allow both temporary i. e. capable of being dismantled, and permanent construction without the use of glue or clamps or other such awkward and messy fittings. Furthermore, it should not require a complicated system to determine the depth of the receiving holes and correctly align the dowels.

According to one aspect of the present invention, there is provided a construction kit suitable for constructing a wall comprising : a plurality of dowels ; and a plurality of blocks, each block having an upper face and a lower face and a plurality of blind recesses formed in each of the upper and lower faces, the recesses being sized to snugly receive the dowels ; whereby a pair of the blocks may be interconnected by insertion of a dowel into a recess in the upper face of one block of the pair and into a recess in the lower face of the other block of the pair.

According to a second aspect of the present invention there is provided A construction kit suitable for constructing a wall, comprising : a plurality of dowels ; and a plurality of blocks, each block having an upper face and a lower face and a plurality of holes extending between the upper and lower faces, the holes being sized to snugly receive the dowels ; each dowel having a radial projection for limiting insertion of the dowel into the blocks ; and the holes including, at at least one of the upper and lower faces, a radially extending recess sized to receive the radial projections ; whereby a pair of the blocks may be interconnected with the upper face of the first block and the lower face of the second block in contact by insertion of a dowel into a first hole of a first block of the pair so as to project from the upper face of that block and into a second hole of a second block of the pair so as to project from the lower face of that block, with the radial projection of the dowel received in the recess.

According to a third aspect of the present invention there is provided a construction kit, suitable for constructing a wall, comprising : a plurality of dowels each having a first generally cylindrical portion at one end which includes a slot and a second generally cylindrical portion at the other end ; a plurality of blocks, each block having an upper face and a lower face and a plurality of holes extending between the upper and lower faces, the holes being sized to snugly receive the dowels ; and a plurality of incompressible pegs sized to be received in the slot of a dowel ; whereby a pair of the blocks may be interconnected by insertion of a second portion of a dowel into a hole of a first block of the pair and the insertion of the first portion of the dowel into a hole in the lower face of a second block of the pair, the shapes of the walls of the slot and of the pegs co- operating such that insertion of a peg into the slot is capable of spreading the said one end of the dowel to a size that fits tightly into the hole.

According to a fourth aspect of the present invention there is provided a wall. comprising : a plurality of dowels ; and a plurality of blocks, each block having an upper face and a lower face and a plurality of blind recesses formed in each of the upper and lower faces, the recesses being sized to snugly receive the dowels ; wherein pairs of the blocks are interconnected by a dowel inserted into a recess in the upper face of one block of the pair and into a recess in the lower face of the other block of the pair.

According to a fifth aspect of the present invention there is provided a wall comprising : a plurality of dowels having a radial projection ; and a plurality of blocks, each block having an upper face and a lower face and a plurality of holes formed between the upper and lower faces, the holes being sized to snugly receive the dowels and at the upper face having a recess shaped to receive the radial projection ; wherein pairs of the blocks are interconnected by a dowel inserted into a hole from the upper face of a first block of the pair and into a hole from the lower face of a second block of the pair, such that the radial projection is received by the recess, thereby limiting the insertion of the dowel in the hole of the first block.

According to a sixth aspect of the present invention there is provided a wall comprising : a plurality of dowels each having a first generally cylindrical portion at one end which includes a slot and a second generally cylindrical portion at the other end ; a plurality of blocks, each block having an upper face and a lower face and a plurality of holes formed between the upper and lower faces, the holes being sized to snugly receive the dowels ; and a plurality of incompressible pegs sized to be received in the slot of a dowel ; wherein pairs of the blocks are interconnected by a second portion of a dowel inserted into a hole from the upper face of a first block of the pair and a first portion of the dowel inserted into a hole from the lower face of a second block of the pair, and the shapes of the walls of the slot and of the pegs co-operate such that a peg inserted into the slot is capable of spreading the said one end of the dowel to a size that fits tightly into the hole.

According a seventh aspect of the present invention, there is provided a dowel having a first plug at one end and a second plug at the other end, and a middle portion between the plugs, each plug having external retaining features arranged to resist its movement in a direction from the respective plug towards the middle portion, the second plug being expandable to cause its retaining features to move radially outwards by means of force applied to the second plug, the middle portion being configured so as to limit insertion of the first plug into a hole in which the first plug is capable of being snugly received.

The invention will now be described by way of example only, with reference to the accompanying drawings in which : Figure 1 is a 3rd angle projection of a block used in construction of a wall according to first and second embodiments of the invention.

Figure 2 shows a dowel suitable for use in constructing a wall according to first and second embodiments of the invention.

Figure 3 shows a wall constructed according to the invention.

Figure 4 shows two blocks being fitted together in a permanent fashion according to a second embodiment of the invention.

Figure 5 shows front views of some differently sized blocks suitable for use in first and second embodiments of the invention Figure 6 shows a block suitable for use at a corner or T-junction in first and second embodiments of the invention.

Figure 7 shows an exploded three-dimensional view of the construction of a corner of a wall, which is three blocks high.

Figure 8. shows the construction of a T-junction.

Figure 9 shows ground plates for anchoring a wall built with the invention.

Figure 10 shows various capping sections.

Figure 11 is a third angle projection of a block used in construction of a wall according to a third embodiment of the invention.

Figure 12 shows front views of some differently sized blocks suitable for use in the third embodiment of the invention.

Figure 13 shows a dowel suitable for use in constructing a wall according to the third embodiment of the invention.

Figure 14 shows two blocks being fitted together according to the third embodiment of the invention.

Figure 15 shows a block suitable for use at a corner according to the third embodiment of the invention.

Figures 16 a-d show a further dowel suitable for use in constructing a wall according to the invention.

Figure 17 shows a wedge for use with the dowel of figure 16.

Figures 18 a-d show the dowel of figure 16 being used to join two blocks together.

In the figures, like reference numerals indicate like parts and lower-case letters are used to distinguish between several like parts.

Figure 1 shows three views of a standard block, indicated generally by reference numeral 1, of a first embodiment of the present invention. Figure 1a is a front view, figure 1 b is a top view and figure 1 c is a side view of a block whose length is six times its width W.

The block 1 is made of wood. A number of different types of wood would be suitable for making the block ; the appropriate one would be chosen for the intended application of the wall to be constructed. The wood of the blocks could be treated to improve its durability or to have a decorative finish. It would of course be possible to use different materials, but wood is probably the most convenient for most applications.

Block 1 is substantially cuboid in shape. It has a width W, a vertical depth D and a length L. The dimensions may vary but in this embodiment the length L is selected to be 6 (figures 1 a-c), 8 (block 100 in Fig 1d) or 10 (block 110 in Fig 1e) x W for every main block. It has a top face 4, a front face 6, a right hand side face 8, a left hand side face 10, and a bottom face 12. It will be appreciated that the block has respective equivalent rear and opposite side faces.

Perpendicular to the top face 4 and centred across the width of the block are drilled four blind holes which have a depth of 2/5D measured from the top face 4 and a diameter of 1/3W. Referring specifically to block 1, the first hole 12 is centred 1/2 W from the left hand side face 8. The second hole 14 is centred 1/2 W from the right hand side face 10. The third hole 16 is centred 1/2 W to the left of the centreline C/L of the block as measured along the length L, and the fourth hole 18 is centred 1/2 W to the right of the centreline C/L. The distance between the centres of holes 16 and 18 is therefore 1 W. The holes all lie on the longitudinal centre line of the top face 4, with their centres therefore 1/2 W from front face 6. Each of these holes has a seat 20 cut around them suitable for accepting the collar 36 on the dowel 2, as will be described below with reference to figure 2.

Equivalent holes, aligned similarly to holes 12, 14, 16, 18 and also having a depth of 2/5D and a diameter of 1/3W are drilled upwards from the bottom face 12 of the block. These are indicated by reference numerals 22, 24, 26, 28 respectively.

These holes do not have a seat cut round them.

Thus it can be appreciated that (ignoring the seats 20) the block is symmetrical about all of its three central axes.

Referring to figures 1d and 1 e, blocks 100 and 110 can be described in a similar manner except the distance between the centrelines of the first holes 12, 22 and the holes 16, 26 is 3W and 4W respectively. Similarly the distance between the centrelines of holes 18, 28 and 14, 24 is 3W and 4W respectively. Thus the total length of block 100 is 8W and the total length of block 110 is 10W.

Figure 2 shows a dowel 2 made from plastic, suitable for use in the invention. It would be possible to use other materials such as wood to make such a dowel.

This dowel is generally circular in cross-section and has a total length of 4/5 D. It has a bottom portion 30 and a top portion 32, both of which are 2/5 D in length.

The bottom portion 30 has a core diameter of 1/3 W and has triangular-shaped grooves 34 around its circumference which extend along most, but not all, the length of the portion. It also has a collar 36 around its top circumference where it meets top portion 32, which is of a size that fits neatly into the seats 20 on holes 12, 14, 16 and 18. The triangular grooves 34 allow the dowel 2 to be easily driven into these holes but make it difficult to remove accidentally. The top portion 32 of the dowel 2 has a core diameter slightly less than 1/3 W and has shallow ribs 38 around its circumference for resisting removal of the dowel once locked in a hole.

Three such ribs 38 are shown in figure 2, disposed at intervals from a top face 40 of the dowel 2, but more or less ribs could be provided. Out of top face 40 is cut a slot 42 across the full width of the dowel 2, thus leaving side cheeks 44 and 46 which can be forced apart. The depth of slot 42 is a little less than half the length of the dowel 2.

The dowel 2 is designed so that when the bottom portion 30 is driven into holes 12, 14, 16, and 18 it becomes fixed such that the collar 36 sits in the seat 20 and the top of the collar 36 is flush with the upper surface 4 of the block 1, 100, 110.

Thus the top portion 32 of the dowel 2 is in a position to receive holes 22, 24, 26, 28.

Figure 3 shows a plurality of blocks similar to block 1 connected to form a wall 48.

The wall is pictured so that the front faces 6 of the blocks are visible. Figure 3a is general view, showing that the wall comprises five layers of blocks 1. The first layer (on the bottom) is layer 50, and the remaining layers are numbered upwards 52, 54, 56 and 58. Layer 58 is a capping section, which will be discussed in more detail below.

In order to construct the wall in accordance with the first embodiment, dowels 2 are hammered into holes 12, 14, 16, 18 of blocks 1 in row 50. The blocks of row 52 are then hammered into place such that the edges align with the horizontal centre line of the blocks of row 50. This means that there will be dowels 2 connecting holes 12 of the row 50 blocks with holes 28 of the row 52 blocks, dowels 2 connecting holes 14 of the row 50 blocks with holes 26 of the row 52 blocks, dowels 2 connecting holes 16 of the row 50 blocks with holes 24 of the row 52 blocks, and dowels 2 connecting holes 18 of the row 50 blocks with holes 22 of the row 52 blocks.

Figure 3b shows this arrangement in greater detail than figure 3a. In figure 3b the holes are shown as dotted lines and the dowels 2 are shown as dot-dash lines.

Next, dowels 2 are hammered into holes 12, 14, 16, 18 of blocks 1 in row 52.

The blocks of row 54 are then hammered into place such that the edges align with the horizontal centre line of the blocks of row 52, so that they are in vertical alignment with the blocks of row 50.

The remaining rows are added in a similar manner so that alternate rows are in vertical alignment.

It can be appreciated that the dowels 2 are sized so that they have a total length of 4/5D, such that the blocks are held tight together, in order to produce a solid wall. They are substantially cylindrical in shape so as to be suitable for fitting in the drilled holes, with a diameter which allows a snug fit, but which is small enough to not require excessive hammering force to construct the wall. It may be preferable for the holes in the blocks to be slightly deeper than 4/5D so as to ensure that the blocks can seat properly on each other even if there are some manufacturing inaccuracies.

Furthermore, since the blocks are merely hammered together and the dowels are suitably sized, whilst the wall is secure for as long as it is needed, it is possible to de-construct it easily, by simply levering the blocks apart. There are no bonding agents such as glue or cement involved, and no metal fixtures such as nails to go rusty.

If a more permanent wall is required, the second embodiment of the invention would be used. This second embodiment uses blocks which are the same as blocks 1, 100, 110 and dowels which are the same as dowels 2 but uses a wedge 60 to force apart the side cheeks 44 and 46 to fix the dowel in its receiving hole, thereby locking the blocks.

Figure 4 shows how the dowel 2 together with a wedge 60 is used to join blocks 1 together, in accordance with the second embodiment. Both figures 4a and 4b show a section through holes 16 and 26, but equivalent pairs of holes along the length of the block would be joined in a similar manner. As previously described dowels 2 are hammered into the top holes 12, 14, 16, and 18 in the lower block 1.

This stage is shown in figure 4a. Then a wedge piece 60 is placed in slot 42 of the top portion 32 of dowel 2, and hole 26 (and equivalent holes not shown in figure 4 along the length of the block) of the upper block 1 is placed on top of the wedge piece 60. As the upper block 1 is hammered into place, the wedge piece 60 is pushed down into slot 42, and in so doing, causes side cheeks 44 and 46 to be pushed outwards towards the edges of hole 26 (and equivalent holes) of the upper block. When upper block 1 has been sufficiently hammered that it has met lower block 1, wedge piece 60 is fully inserted in slot 42 and side cheeks 44, 46 are pressed firmly against the sides of hole 26 (and equivalent holes). This means the two blocks are held together more strongly than the blocks of the first embodiment, and of course would be harder to disassemble.

It can also be seen from figure 4 that the top portion 32 of the dowel 2 is slightly smaller than holes 22, 24, 26, 28. This allows room for the outward movement of portions 44, 46. Furthermore, wedge piece 60 is slightly wider than the slot 42, so that when the upper block is hammered into place, it will force portions 44, 46 outwards.

The wedge pieces 60 could be sized so as not to need to travel fully into the slots 42 in order to provide satisfactory locking. It is not necessary for the slots 42 and the wedges 60 to be shaped as shown. One of them could be of another shape.

It will be appreciated that an entire wall can be created using the blocks 1, 100, 110, dowels 2 and wedge pieces 60 and that when constructed the wall will assume a similar appearance to the wall of the first embodiment as shown in figure 3a.

The invention is not limited to the sizes of standard blocks shown in Figure 1.

Figure 5 shows examples of other possible lengths of blocks. These other lengths could be used as"fill-in"blocks together with standard blocks in order to vary the resulting length of the wall being built. In the top surface the holes are recessed, the same as holes 12, 14, 16 and 18 in the standard blocks 1, and in the bottom surface the holes are not recessed, the same as holes 22, 24, 26, and 28 in standard blocks 1.

Figure 5a shows fill-in block 62 of length 2W, with two holes drilled in the top and bottom, centred 1/2 W from the ends of the block and W apart.

Figure 5b shows fill-in block 64 of length 3W, with two holes drilled in the top each centred 1/2 W from the ends of the block, and three holes drilled in the bottom, the first centred 1/2 W from the end of the block, the second centred W from the first hole and the third centred W from the second hole, which is also 1/2 W from the far end of the block.

Figure 5c shows fill-in block 66 of length 4W, with two holes drilled in the top each centred 1/2 W from the ends of the block, and four holes drilled in the bottom, the first centred 1/2W from the end of the block, the second centred W from the first, the third centred W from the second and the fourth centred W from the third, which is also t/2 W from the far end of the block.

Figure 5d shows fill-in block 68 of length 5W, with two holes drilled in the top each entered 1/2 W from the ends of the block, and five holes drilled in the bottom. The first of these is centred 1/2 W from the end of the block, the second is centred W from the first hole, the third is centred W from the second hole, the fourth is centred W from the third hole and the fifth is centred W from the fourth hole which is also 1/2 W from the far end of the block.

These fill-in blocks 62, 64, 66, and 68 could be used to create a wall to within a tolerance of 1W in length.

Fill-in blocks 64, 66, and 68 could be used to square off the end of the wall of Fig 3a as they are half the length of the standard Blocks shown in Fig 1.

Fill-in Block 62, 64, and 66 are essential for the construction of corners and T- junctions as will be explained below.

It should also be noted that blocks 62, 64, 66 and 68 demonstrate an important principal of the invention, in that the differently-sized blocks are designed to be compatible with one another so that when they are joined together, there are always the correct number of holes on the upper surface 4 of the block all of which are filled by dowels 2, thus preventing them filling with water, should the wall be exposed to rain or other liquids.

The building of any rectilinear or interlocking rectilinear structure requires the construction of corners and'T'Junctions. Figure 6 shows a corner block 70 that allows this. It has the same dimensions as a standard block 100 and holes of the same dimensions, shape and position as in the standard block 100. However, there is an additional hole 72 on the top face 4, and an additional hole 74 on the bottom face 12. These additional holes 72, 74 have the same dimensions and shape as the holes on the top and bottom faces of the standard block 100. They are centred 1W to the right along the length of the block of hole 12 on the top face 4 and 1W to the right of hole 22 on the bottom face 12. It therefore follows that holes 72 and 74 are centred 1 % 2 x W from the left hand edge 8.

Like the standard block 1 as shown in figure 1, in this embodiment the corner block 70 can be one of three lengths, that is 6, 8, or 10 times W. The corner blocks are used in conjunction with standard block 1, 100, 110 of the same length and the appropriate fill-in blocks 62, 64, and 66 to form corners and T-junctions.

Figure 7 shows three layers of blocks forming a corner in isometric projection and exploded for clarity. It will be appreciated that the layers extend beyond the parts shown in the figure. The bottom layer is labelled 72, the second layer is labelled 74 and the top layer is labelled 76. The principle of construction could be extended to more layers as required. Each layer can be considered to be constructed from a right hand wall as viewed and a left hand wall. Thus layer 72 is constructed from right-hand wall 82 and left hand wall 83. Similarly, layer 74 is constructed from right-hand wall 84 and left hand wall 85 and layer 76 is constructed from right-hand wall 86 and left hand wall 87. The construction method of each wall is the same as described for wall 3a.

In order to construct the corner a corner block 70a is used as the last block of the right hand wall 82 on the first layer 72 and the corner is turned using fill-in block 64a the length of which is half the length of a standard block 100 minus W, thus forming the end of left hand wall 83. If a standard block 1 of length 6 x W were being used fill-in block 62 which has a length of 2 x W would be used instead of fill-in block 64a. If the standard block 110 of length 10 x W were being used then fill-in block 66, which has a length of 4 x W, would be used.

Similarly, fill-in block 64b is used as the last block of the right hand wall 84 of layer 74 and the corner turned using a corner Block 70b, arranged such that its holes 12, 22 are on the corner, thus forming the end of left hand wall 85. Layer 76 is identical to layer 72. In each layer the use of a corner block 70 and an appropriate fill in block 64 ensures a locked corner with three holes for dowels. It can be seen how the design of the corner blocks and fill-in blocks ensures alignment of holes in adjacent layers in the corner region. For example, hole 12 of block 70a aligns with hole 22 of block 70b, hole 72 of block 70a aligns with a hole of block 64b and a hole of block 64a aligns with hole 74 of block 70b. This further means that the blocks lie flush with one another to make a neat corner.

For example, the end face of block 70a and the side face of block 64a are aligned flush with one another, and they are also flush with the side face of block 70b in the layer 74. above.

The blocks fitted adjacent to blocks 70a, 70b, 64a, 64b are standard blocks 1, such that the walls are continued in a normal manner as described with reference to figure 3a.

Figure 8 shows two walls 80 and 81 meeting at an angle of ninety degrees, thus forming a T-junction. The construction of each of these two walls is the same as described with reference to Figure 3a. It will be appreciated that the walls can extend for any length beyond that shown in the figure.

Figure 8d shows a front view of the T-junction, in which only wall 81 is visible.

Five layers of blocks are shown, but of course the walls 80, 81 could be extended to form more layers. The bottom layer is labelled with reference numeral 150, and the subsequent layers are labelled 152, 154, 156, 158.

Figure 8a shows the bottom layer 150 viewed from above. As viewed, wall 81 is horizontal and wall 80 meets it at right angles and extends vertically up the page.

Three corner blocks 70 form the T-junction. As viewed, the last block 70c in wall 80 is a corner block 70 positioned so that its end face 8 with the double dowel holes 12, 72 is flush with the front face of wall 81. Each side of block 70c are two corner blocks, 70d on the left hand side and 70e on the right hand side. This means that in this layer 150, wall 81 is effectively split into two portions by wall 80.

Blocks 70d, 70e are positioned so that their front faces 6 are in line with the end face 8 of block 70c and their end faces, nearest the double holes 12, 72, abut block 70c, giving a row of five dowel holes 72d, 12d, 12c, 12e, 72e along the line of wall 80, with the centre hole 12c in line with the centre lines of both walls 80, 81.

Figure 8b shows the second layer 152 viewed from above. A fill-in block 64c, which has receiving holes for three dowels in its bottom face, is fixed over the centre three dowels 12d, 12c, 12e of layer 150. Thus the reason for the centre hole in the bottom face of fill-in block 64 shown in figure 5b can be appreciated.

Adjacent each side of block 64c along the line of wall 81 are fixed further fill-in blocks 64. Block 64d is on the left hand side as viewed, and is fixed to layer 150 over the centre of holes 18 and 72d of block 70d with the outermost two of the holes in its bottom face (not visible in figure). Similarly, block 64e on the right hand side as viewed, is fixed to layer 150 over the centre of holes 18 and 72e of block 70e with the outermost two of the holes in its bottom face (not visible in figure). At right angles to block 64c along the line of wall 80 is fixed fill-in block 64f. This is fitted over holes 72c and 18 of block 70c with the outermost two of the holes in its bottom face (not visible in figure).

Figure 8c shows the third layer 154 viewed from the top, which is identical to the first layer 150 shown in figure 8a.

The blocks adjacent to the above-mentioned corner and fill-in blocks are standard blocks 1, thus continuing the layers in the normal manner.

It will be appreciated that the use of corner blocks 70 and fill-in Blocks 62, 64, 66, 68 will allow the construction of strengthening pillars, alcoves and other features in the wall, and will allow projections from the wall which will allow the attachment to the wall of seats and other equipment.

Figure 9 shows ground plates which will allow any wall or structure, constructed using the invention, to be fixed in position.

Figure 9a shows the side and end elevation of a ground plate 96 which has a width preferably between 1/2 W and 3/4 W and a length of 2W. Two half dowels 92, of a size that will fit into the holes on the bottom face 12 of the standard block 1, are permanently fixed to the plate 96, centred 1W apart and 1/2 W from the ends of the plate. In the centre of plate 96 is a threaded countersunk hole 98 into which a ground spike 94 of generally conical shape can be screwed before being driven into the ground in the required position. This makes an ideal way of securing a wall constructed in accordance with the invention into, for example, grass.

Alternatively, the ground plate could be fixed to the ground by a pin like a large nail. Alternatively if the structure is to be erected on a surface into which it is impossible to drive ground spikes then a countersunk screw can be used, being screwed into a pre drilled hole into which a rawl plug or similar device has been fitted. Alternatively the ground plate could be held in place by the weight of the structure alone, but this would not be a suitable arrangement for a large wall for safety reasons.

Figure 9b shows a top view of a right-angled ground plate 93 with three half dowels 92 positioned to correspond to the position of the bottom holes at a corner, and two countersunk threaded holes 98. It is for use at corners of the type described with reference to figures 6 & 7 and is used in a similar way as straight ground plate 96 of figure 9a.

Figure 9c shows the top view of a T shaped ground plate 95 with four half dowels positioned to correspond to the position of the bottom holes at a T-junction, and three countersunk holes 98. It is for use at T-junctions of the type described with reference to figure 8 and is used in a similar way as straight ground plate 96 of figure 9a. Alternatively, an L-shaped corner plate could be used at T-junctions.

The L-shaped plate could have four through-holes in total : three in one strip and two in a perpendicular strip. Two wall sections could be butted together over one strip of the plate and the perpendicular wall section of the tee on the other strip.

The plates, half dowels and the ground spikes would be constructed from a suitable plastic or from steel. It would probably be most convenient to manufacture the plates with the half-dowels pre-attached, but this is not strictly necessary. The shape and positions of holes in the ground plates could be varied.

Figure 10 shows various capping sections in end views of walls. These are for use as the top layer of a wall, and therefore do not have upper holes drilled in them. The arrangement of lower holes would correspond to the blocks being used to construct the wall. Their length matches the blocks being used.

Figure 10a shows a block capping section 102 attached to a block 1 with a dowel 2. Figure 10b shows a flat capping section 104 and figure 10c shows a biased capping section 106. Other shapes of capping section would be possible. Any capping section could be used with the standard blocks 1, 100, 110. Capping corner sections and T-junction sections could also be provided and used in accordance with the construction pattern explained with reference to Figures 7 & 8.

Once constructed, the wood of the blocks and capping sections could be sealed or painted as desired. Alternatively, the blocks and capping sections could be supplied pre-sealed or pre-painted. The shape of the capping sections could be varied from the examples shown in the figures.

Figure 11 shows three views of a standard block 200 for use in accordance with a third embodiment of the present invention. Figure 11 a is a front view, figure 11b is a top view and figure 11c is a side view. This block has the same general properties of blocks 1, 100 and 110 and can have a length of 6W, 8W or 10W in this embodiment, although the invention is not limited to these three lengths.

The difference between block 200 and blocks 1, 100, 110 is in the form of the holes 212, 214, 216, 218. These are drilled in the same locations as the holes of blocks 1, 100, 110, that is, 1/2W from each end of the block 200 and 1/2W either side of the centreline C/L, but instead of being blind holes, they are drilled through the entire depth of the block 200. They have seat 20 cut out at the upper surface of the block 200. Holes drilled in this way would allow an even greater economy of manufacture than the holes of the first and second embodiments and would be suitable if the dimensions of the block were too small to support blind holes. A further advantage is provided when fixing the blocks together, as will be discussed below.

Figure 12 shows examples of other possible lengths of blocks, which are suitable for use as fill-in blocks in accordance with the third embodiment in a similar way as the fill-in blocks of figure 5 are used in accordance with the first and second embodiments. These blocks differ from fill-in blocks 62, 64, 66, 68 in that the holes are drilled through the entire depth of the block.

Figure 13 shows a dowel 202 for use in the third embodiment which differs from dowel 2 of figure 2 in its length. Instead of each portion of the dowel being 2/5D in length, each portion is just slightly less than t/2D in length. The top portion is indicated with reference numeral 232 and the bottom portion is indicated with reference numeral 230. Bottom portion 230 bears collar 36 around its top circumference for fitting neatly into seat 20. Top portion 232 has a slot 242 which is similar in shape to slot 42 but whose length is increased in proportion with the overall difference in length between dowels 2 and 202.

Turning now to figure 14, the fitting together of two blocks 200a and 200b can be understood. The first stage is shown in figure 14a, in which the bottom portion 230 of a first dowel 202a is hammered into a hole 212 in block 200a. Despite the fact that hole 212 is not a blind hole, the dowel 202a is stopped in the correct vertical position by virtue of collar 36 fitting into seat 20. The upper portion 232 of dowel 202a rests above the upper surface of block 200a. A wedge piece 260 is then gently hammered into slot 242 in the upper portion 232 of dowel 202a. The dimensions of wedge piece 260 may be similar or slightly different to those of wedge piece 60.

Figure 14b shows the second stage of the process in which a second block 200b is placed on top of block 200a, such that hole 218 of block 200b is in alignment with hole 212 of block 200a, in accordance with the alignment requirements as explained with reference to figure 3. This means that the hole 218 of block 200b is placed on top of upper portion 232 of dowel 202a containing wedge piece 260.

Then a second dowel 202b is placed into hole 218 at the upper surface of block 200b.

Figure 14c shows that the final stage is to hammer dowel 202b downwards towards dowel 202a and wedge piece 218. As dowel 202b is hammered into place, wedge piece 260 is pushed downwards into slot 242 such that it forces side cheeks 244 and 246 outwards. When dowel 202b is seated in seat 20 of block 200b by virtue of collar 36, cheeks 244 and 246 have been sufficiently forced outwards to afford a permanent fixing of blocks 200a and 200b, in a similar way to the second embodiment shown in figure 4.

It can be understood from figure 14 and the description above that the two portions 232, 230 of dowel 202 are sized at slightly less than Y2D so that when in position fixing two blocks 200 as shown in figure 14c, the two dowels do not touch, but rather leave room for the wedge 260 not being fully flush in slot 242.

If it is desired to construct a less permanent wall, the blocks 200 could be connected without using the wedges 260. Since the collar 36 is designed to sit in seat 20, the blocks will be held flush together even though there is not a blind recess for the dowels 202 to sit on.

If an even greater economy of manufacture is desired, the holes 212, 214, 216, 218 could be provided without seat 20, thus they would be simple drilled holes.

Accordingly, dowels 202 would not be provided with collar 36. The above- described embodiment would still allow the blocks to be fixed together because instead of the dowel 202b resting on seat 20, it would rest on wedge 260.

However, so as to avoid damage to the components, there would need to be provided some sort of indication, for example a visual indication such as a mark or groove, of the mid-length point of the dowel, so that a user would know when to stop hammering, otherwise wedge 260 could be hammered too far into slot 242.

If this option were to be implemented for the construction of a less permanent wall, one or both portions of the dowel would need to be lengthened to make the total length of the dowel equal to D, so that the dowels would be held in place by resting on top of one another. This option may be less preferred when selling wall construction kits because it would require such a kit to be provided with two sets of dowels, one for a permanent wall and the other for a less permanent wall.

The process would be the same for the equivalent holes in blocks 200a and 200b and the process could furthermore be used to construct a wall in accordance with figure 3. The advantage that this process brings over the first and second embodiments is that there is no need to hammer the blocks themselves, but rather it is always the dowels 202 which are hammered. This is useful if it is undesirable to hammer the blocks directly, for example if they are pre-painted and damage to the paint needs to be avoided.

Figure 15 shows a corner block 170 suitable for use in accordance with the third embodiment. This block differs from corner block 70 in that the holes 212, 214, 216, 218, 272 are drilled through the entire depth of the block as opposed to being blind holes.

It will be appreciated that fill-in block 264 of figure 12 and corner block 170 of figure 15 can be used to construct a corner in accordance with figure 7, using the method described above with reference to figure 14.

When constructing a wall in accordance with the third embodiment, the same ground plates and capping sections of figures 9 and 10 are used, as described above with reference to those figures.

It will be appreciated that other sizes of blocks can be used, with different arrangements of holes. It would also be possible to use holes and dowels of a different shape, for example square. Furthermore, if desired, the blocks could be constructed with dowels incorporated, for example, just in the upper faces, although this would be likely to make a kit more expensive. The holes could of course be formed by a method other than drilling. In certain forms, the construction kit would be suitable for use as a toy.

The actual dimensions of the blocks and dowels could be widely varied, depending on the intended application. It would be possible to provide, for example, a block with two holes drilled at either end and two in the middle, depending on the particular construction arrangement desired. Furthermore, it is not necessary for all the holes in a particular block to be the same size, although since suitably sized dowels are needed for proper construction of a wall, economy of manufacture and packing is maximised by using identically sized holes.

Although wood is the most suitable material for the blocks, other materials such as plastics or metals could be used. The blocks and dowels could be sold as a kit for building a particular-sized wall, or could be sold loose, so that customers could buy exactly the number required and could vary the dimensions of the wall and the choice of capping section. In the second and third embodiments the shape of the wedges and wedge pieces could be varied within the scope of the invention.

The shape of the ground plates and positions of holes in the ground plates and capping sections could be varied as necessary in accordance with the position of holes in the blocks.

It is not necessary for the dowels to have a diameter in the region of 1/3 of the width of a block. It may be more convenient for them to have, for example a diameter in the region of 1/4 of the width of a block. In this instance, the block might have a depth of 4W and a width of 4W, but the same dowels as those for the block having a width of 3W could be used, and hence these dowels would have a diameter in the region of l/4 of the diameter of the block with a width of 4W. It is not necessary for the width and depth to be the same, for example, the width could be 3W and the depth 4W. Thus different sized blocks could be used for different applications, but it could still be possible to use common dowels.

A further possibility when constructing a wall in accordance with the invention, is to construct the wall entirely from the corner blocks of figures 6 and 15. This would mean that the additional holes 72, 172 (additional to those provided in the standard blocks) would be present in all the blocks. This variation would be most advantageously used in the embodiment having the holes drilled through the entire depth of the block, so that there would be no build-up of rainwater in unused holes. Another way of avoiding build-up of rainwater would be to use the capping sections.

Fig 16a shows a side elevation and figure 16b shows a top elevation of a different dowel, labelled generally with reference numeral 302. Figure 16c shows a cross section through the dowel 302 at line X-X'of figure 16b and figure 16d shows a cross section of the dowel 302 at line Y-Y'of figure 16a. This dowel is particularly suitable for use with block 200 of figure 11 and its associated blocks, as will be explained below.

Dowel 302 is made from plastics material such as Nylon or polyethylene and has a total length which is less than the depth of the block 200. It is very generally cylindrical in cross section and has a bottom portion 303 and a top portion 304, which are rotationally fast with respect to one another. It would be possible to use other materials such as wood to make such a dowel, but plastics materials have the advantage that they can conveniently be moulded to shape.

The bottom portion 303 has a collar 306 around its top circumference where it meets top portion 304. The collar 306 projects radially from the bottom portion 303. The collar 306 is of a size that fits neatly into the seat 20 recessed into the holes 212, 214, 216, 218 in the block 200, but will not pass through the through- bore sections of the holes. Around most of the remainder of the circumference of the bottom portion 303 run spaced-apart circumferential grooves 381 of triangular cross-section, which define corresponding spaced-apart circumferential teeth 382 around the bottom portion 303. The maximum diameter of the bottom portion at the tips of the teeth is slightly larger than the diameter of the through-bore sections of the holes in the block 200. This means that a certain amount of force is required to insert bottom portion 303 in a block 200 and a tight fit will be achieved. By virtue of the teeth being oriented in an upwards configuration, they allow the dowel 302 to be relatively easily driven into the holes of block 200 but make it difficult to remove accidentally. The arrow-shaped groove 311 shown in figure 16, which intersects the teeth, is a decorative feature on which can be engraved writing or a trademark or symbol etc. It also indicates to a user that the bottom portion of the dowel, on which it is formed, should be inserted into a block before the upper portion, and in the direction shown by the arrow.

The top portion 304 has a maximum diameter that is slightly less than that of the holes 212, 214, 216, 218 in the block 200. Around its circumference run recessed grooves 309 defining between themselves several horizontal ribs 310 for resisting removal of the dowel once locked in a hole. It should be noted that the peripheral surfaces of these ribs 310 are set at an angle greater than vertical as measured outwards from the centre of the dowel 302 so that they effectively point outwards and downwards. Thus, when the top portion is inserted into the hole in the bottom of a block and its diameter expanded as will be explained below, the ribs 310 can act to restrict relative movement to remove a block upwards from the dowel 302 in an analogous way to the teeth 382 but in the opposite direction. More or less ribs 310 than are shown in figure 16 could be provided.

Running vertically from the top 318 of dowel 302 almost the full length of the top portion 304 and cutting through the ribs 310 are two grooves 312 positioned opposite one another around the circumference of the top portion 304 of the dowel 302. The dashed lines in figure 16c show that the thickness of the material at these two grooves is very small in comparison to the general material thickness elsewhere on the dowel, so that only a thin layer of material 314 separates the base of the grooves 312 from the sidewall of a central hole 316 of dowel 302.

The reason for this will be explained below when use of the dowel 302 is discussed.

It would be possible to use grooves, teeth and ribs of different shapes from those shown in figure 16.

Centrally positioned and running the full length of the dowel 312 is central hole 316, which has a circular cross-section. This hole is widest at the top 318 of the dowel 302 and evenly tapers down to a smaller diameter at the base 320 of the dowel. Hole 216 is sized so that in the region of base 320 it fits snugly over the top of a wedge (to be described with reference to figure 17) and in the region of top 318 it can comfortably receive the tip of the wedge. As a consequence of this taper the walls 322 of the upper portion 304 of dowel 302 are thinner than the walls 324 of the lower portion 303. The outer base 326 of the dowel 302 where the side walls are thickest is finished square.

In general terms, the dowel 302 is designed so that when the bottom portion 304 is driven into holes 212, 214, 216, and 218 of a first lower block 200a, it becomes fixed such that the collar 306 sits in seat 20 and the top of the collar 306 is flush with the upper surface 114 of the block 200a. Thus the top portion 304 of the dowel 302 is in a position to receive holes 212, 214, 216, and 218 of a second, identical upper block 200b to be placed on top of the first block 200a. At that point, the teeth 382 hold the dowel fast in the holes of the lower block. However, since the diameter of the top portion of the dowels is less than that of the holes in the upper block, the upper block can be slid easily down to envelop the projecting upper portions of the dowels.

Fig 17a shows a side view and figure 17b shows a top view of a generally conical wedge, indicated generally with reference numeral 327. Figure 17c is a cross- sectional view taken along the line A-A'through conical wedge 327. It is conveniently made from the same or a slightly harder material than the dowel. It is generally circular in cross section and its total length is about half the total length of the dowel 302 shown in Fig 16.

The upper portion 328 of conical wedge 327 is a peg with a rounded top 330. It is generally cylindrical with four sections 329 removed leaving a section in the form of a right-angled cross which extends down the length of the upper portion 328 in the form of ribs 331. The diameter of this upper portion 328 is slightly larger than the diameter of the hole 316 of the dowel 302 at its bottom face 320, so that when the upper portion 328 is pushed by hand from the bottom of the dowel into the hole 316 of the dowel 302 it is held in position in a snug fit, as mentioned previously.

The lower portion 332 of conical wedge 327 has a length that is less than the upper portion 304 of the dowel 302. It is generally shaped as a truncated cone with a rounded end 334. The widest part 336 of the cone, adjacent to upper portion 328, has a diameter that is at least 20% larger than hole 316 at the top 318 of the dowel 302. The wedge 327 has no grooves at this point, thus material extends around its whole circumference so it is cylindrical here. As its diameter is greater than the adjacent upper portion 328, it forms a square shoulder 338.

Consequently, when the upper portion 328 of the wedge 327 is pushed into dowel 302, as will be explained below, the shoulder 338 sits on the square cut base 326 of the dowel around its whole circumference.

The rounded end 334 of the wedge 327 has a diameter which is slightly less than hole 316 at the top 318 of the dowel 302 so that when the wedge 327 is pushed by hand into the top of the dowel 302 it can be held in position.

From the shoulder 338 to the rounded end 334 of the wedge 327 four hollows 339 are removed leaving four prominent ridges 340 arranged in cross-section as a right angled cross which extends up the wedge 327 to shoulder 338, apart from in the close vicinity of shoulder 338, at which point the wedge 327 is cylindrical, as mentioned previously.

The dowel 302 is designed so that it may be used for temporary constructions, which can be levered apart, or when used in conjunction with the wedge 327, for a more permanent wall structure that would be more rigidly fixed together and more difficult to dismantle. In both cases the bottom portion 303 of the dowel 302 is driven into pre-drilled holes 212, 214, 216, 218 of a first, lower block 200a, until the collar 306 sits in recess 20 (Fig 18a). The teeth 382 facilitate this and prevent the easy removal of the dowel 302 by virtue of their upwards configuration. The upper part 304 of the dowel 302 protrudes from the top face 4 of the first, lower block 200a and the pre-drilled holes of a second, upper block 200b are placed over these and pushed firmly into position (Fig 18b).

If the wall construction is to be temporary, the wedge 327 is not used but dowels 302 are simply inserted into the pre-drilled holes of the next and subsequent layers of blocks. Since the collar 306 of dowel 302 is designed to sit in seat 20, when a dowel 302 is placed in a lower block 200a, its movement will stop when the collar is seated in seat 20, so that the blocks 200a, 200b will sit flush together.

Furthermore, since the blocks are merely butted together and the dowels 302 are suitably sized, whilst the wall is secure for as long as it is needed, it is possible to de-construct it easily, by simply levering the blocks apart. There are no bonding agents such as glue or cement involved, and no metal fixtures such as nails to go rusty.

However, if a more permanent structure is required use is made of conical wedges 327. The construction process will now be described in more detail with reference to figures 18a to 18d.

Figure 18a shows the first stage of joining together a first, lower block 200a and a second, upper block 200b. The bottom portion 303 of a first dowel 302a is hammered into a hole 212 in block 200a. The dowel 302a is stopped in the correct vertical position by virtue of collar 306 fitting into seat 20 of block 200a.

The upper portion 304 of dowel 302a rests above the top face 4 of block 200a.

Next, upper portion 328 of a conical wedge 327 is pushed into hole 316 from the base 320 of a second dowel 302b.

Referring now to figure 18b, a second block 200b is placed on top of first block 200a so that drilled receiving hole 218 of block 200b fits over upper portion 304 of first dowel 302a and blocks 200a, 200b are held flush together. The reason that it is hole 218 of block 200b rather than hole 212 is because of the preference for constructing a wall with alternate layers of bricks being in a staggered arrangement, as has been described earlier. Then, the dowel 302b, complete with wedge 327, is hammered vertically downwards into hole 218 of second, upper block 200b, so that the rounded end 334 of the wedge 327 centres over hole 316 of dowel 302a and has moved some way into it.

Having reached this stage, some force is required to drive wedge 327 further into hole 316 of dowel 302a in order to make the construction permanent in nature and to allow the lower portion 303 of dowel 302b to be pushed into block 200b until collar 306 sits flush in recess 20. This stage is shown in figure 18c.

In order to drive the dowel 302b further into hole 218 of block 200b, use is made of the fact that the square base 326 of the walls 324 of dowel 302b acts on the shoulder 338 of the wedge 327 and as the lower part of the dowel 302b is hammered into hole 218 the wedge 327 is forced into hole 316 of the first dowel 302a, the collar 306 preventing the lower dowel 302a from being forced downwards. As the wedge 327 is forced into hole 316 the four ridges 340 of the wedge 327 stretch the thin material 314 at the base of the grooves 312 in the upper portion 304 of the dowel 302a, forcing the ribs 310 against the wall of hole 218 of block 200b and locking the dowel 302 firmly in position. The final position is shown in figure 18d, in which seats 306 of blocks 200a, 200b are both flush with the top faces 4 of their respective blocks. It is convenient for thin material 314 to be frangible so that one or both of grooves 312 splits, thus separating upper portion 304 of dowel 302a vertically, which allows it to be forced against the walls of hole 218.

To protect the dowel 302b from damage whilst being hammered into position, a steel sleeve 342, whose length is slightly longer than the upper portion 304 of the dowel 302b is fitted over the top portion 304 of the dowel 302b so that its bottom edge rests on the upper surface of the shoulder 306. The steel sleeve 342 is generally cylindrical in shape and is open at its bottom end so that it can be fitted over the dowel 302b. Its top end is a suitable shape to minimise deformation during repeated hammering and to efficiently transfer the impact force to the dowel 302. Thus the force of hammering is transferred directly and evenly onto the stronger lower portion 303 of the dowel 302. A suitably tough material other than steel could be used.

It can be understood from figure 18d and the description above that the lengths of the two portions 303, 304 of dowel 302 are sized at slightly less than 1/2D so that when in position fixing two blocks 200a, 200b, the two dowels 302a, 302b do not touch. Instead they are separated by roughly the depth of cylindrical portion 336 of wedge 327.

As is understood from figure 11, in order to connect any given two blocks, there will be more than one dowel connection required. Thus in practice, the above- described process would be the same for the equivalent holes in blocks 200a and 200b and the process could furthermore be used to construct a wall as described earlier. One advantage that this process brings is that there is no need to hammer the blocks themselves, but rather it is always the dowels 302 via sleeve 342 which are hammered. This is useful if it is undesirable to hammer the blocks directly, for example if they are pre-painted and damage to the paint needs to be avoided.

If it is required to make a temporary construction more permanent, the blocks can be levered apart since the upper part of dowel 304 is slightly smaller than the pre drilled holes. The lower portion of the dowels 302 will however remain fixed in their holes. It would be possible to completely remove the dowels 302 should this be necessary, but some force would be required to act against triangular teeth 382. Otherwise, to re-erect the structure or reuse the blocks 200 in a more permanent manner the bottom of the wedge 334 is pushed into hole 316 of the protruding half 304 of a dowel which remains fixed in a hole 212, 214, 216, 218.

As the upper block, complete with its dowels, is placed in position, the rounded ends 330 of wedges 327 centre on holes 316 of dowels 302 contained in the upper blocks. As the block is hammered into position the wedge is driven in and the two blocks are permanently fixed.

Any structure constructed as described above can be fitted to the ground using ground plates and can be finished off using capping sections as described earlier.

It will be appreciated that other sizes of blocks can be used, with different arrangements of holes. It would also be possible to use holes and dowels of a different shape, for example square. Furthermore, if desired, the blocks could be constructed with dowels incorporated, for example, just in the upper faces, although this would be likely to make a kit more expensive. The holes could of course be formed by a method other than drilling. In certain forms, the construction kit would be suitable for use as a toy.

It would also be possible to provide the dowels with a built-in wedge attached to the bottom, so that the whole would then be inserted into a hole in a block as per figure 18c. Such a wedge could optionally be formed so as to be easily detached from the dowels as desired.

The actual dimensions of the blocks, dowels and wedges could be widely varied, depending on the intended application. Furthermore, it is not necessary for all the holes in a particular block to be the same size, although since suitably sized dowels are needed for proper construction of a wall, economy of manufacture and packing is maximised by using identically sized holes. Although wood is the most suitable material for the blocks, other materials such as plastics or metals could be used. The blocks and dowels could be sold as a kit for building a particular- sized wall, or could be sold loose, so that customers could buy exactly the number required and could vary the dimensions of the wall and the choice of capping section. The shape of the dowels and wedges could be varied within the scope of the invention.

It would also be possible to use a wall constructed in this way for many other applications. In particular, such a wall could be used horizontally for decking and tabletops. It could also be used (in various sizes and dimensions) for fixing panels, block paving, finials, timber edging etc. It would also be useful for holding awkward shaped pieces of wood together whilst gluing two surfaces together.