FIELD OF THE INVENTION

The invention relates to stackable toy blocks and graphical representations thereof. BACKGROUND Conventional cubic toy blocks have been popular toys for generations. Variants of such blocks carry respective image portions in the form of a letter on each of their faces whereby the blocks may be arranged side by side to form an image in the form of a word.

Such conventional blocks are readily stacked one atop the other, however their utility in this respect is limited in that only friction prevents relative horizontal movement of the blocks so that structures formed by such blocks are unstable. Moreover the simple right angled geometry of the cubes only holds a child's interest for so long.

Other blocks have been developed which can be stacked more stably. These other blocks have a broadly right hexahedral shape. An array of short cylindrical studs projects upwardly from the top surface of the blocks. The blocks are downwardly open to reveal an internal void. Structure within the void defines void portions for respectively receiving the studs of a like or similar underlying block. The studs form a positive stop to block, in the manner of a key, relative horizontal movement of the blocks. The structure within the void and the studs are also cooperatively dimensioned to form an interference fit to resist vertical separation of the blocks.

Such other blocks require a degree of dexterity to align and interlock the studs with the void portions. This degree of dexterity can be beyond that of an infant otherwise interested in and capable of stacking blocks. Moreover these blocks still retain simple right angled geometry with which children can lose interest. These blocks can be expensive. Careful design and tight manufacturing tolerances are required to achieve a satisfactory fit between the blocks. High quality materials are required to minimize the amount by which the blocks change shape over time to maintain this fit. Careful design and high quality material are also required to ensure that the structure within the voids and the studs do not fail under shear loading.

Various aspects of the invention aim to provide improvements in toy blocks and graphical representations thereof or at least to provide an alternative in the market place.

It is not admitted that any of the information in this patent specification is common general knowledge, or that the person skilled in the art could be reasonably expected to ascertain or understand it, regard it as relevant or combine it in any way at the priority date. SUMMARY

One aspect of the invention provides a toy block and one or more other toy blocks, the block being stackable atop the other block(s) wherein: one or both of a bottom of the block and respective tops of the other block(s) includes inclined portions arranged such that horizontally driving the block, in any direction, relative to the other block(s) elevates the block whereby the block is stably retained; and the block and one or more of the other blocks respectively carry portions of one or more images and are interlockable to form the image(s).

The block and the other blocks may be of substantially the same shape. The block preferably includes two wide side walls and two narrow side walls arranged so that the block is at least approximately rectangular when viewed in plan. Most preferably the walls define a rectangular horizontal cross section. Preferably at one or both of the top and the bottom of the block each of the narrow side walls are alike to align with a narrow side wall of a like block in a like orientation. It is also preferred that at one or both of the top and the bottom of the block at least one of the wide side walls has an end portion complementary to at least one of the narrow side walls to align with a narrow side wall of a perpendicular like block.

According to preferred forms of the invention at one or both of the top and the bottom of the block each of the side walls is at least approximately sinusoidal and has a pitch. Preferably the pitch is equal to the width of the wide side walls, and/or the pitch is twice the width of the narrow side walls.

It is preferred that one or both of a bottom of the block and respective tops of the other block(s) are smoothly curved. Alternatively, the one or both of the tops and/or bottom of the blocks may be faceted. Most preferably the block is shaped for a substantially conformal fit with the other block(s).

Preferably the block has a volume of less than about 1 L. It is preferred that the block weigh less than about 3 kg, or more preferably less than about 0.2 kg.

Preferably the blocks are stackable to present two or more distinct external faces which each carry a respective one of the images. In a preferred form of the invention the blocks are stackable to present at least six external faces at least five of which carry a respective one of the images. In certain variants of the invention the blocks are stackable to conceal one or more of the images. Optionally the image portions are erasable. Another aspect of the invention provides a computer readable medium carrying instructions executable to cause a computer to: display a graphical representation of the above blocks; and interlock the graphical representations in response to user input.

Another aspect of the invention provides a computer readable medium carrying instructions executable to cause a computer to: display a graphical representation of a toy block and one or more other toy blocks, the block being stackable atop the other block(s) wherein one or both of a bottom of the block and respective tops of the other block(s) includes inclined portions arranged such that horizontally driving the block, in any direction, relative to the other block(s) elevates the block whereby the block is stably retained; interlock the graphical representations in response to user input; and reward the user for successfully interlocking the blocks. Another aspect of the invention provides a toy block, one or more other toy blocks and a marking implement for creating image portions on the blocks; the blocks being stackable atop the other block(s) wherein one or both of a bottom of the block and respective tops of the other block(s) includes inclined portions arranged such that horizontally driving the block, in any direction, relative to the other block(s) elevates the block whereby the block is stably retained. Preferably the created image portions are erasable.

Another aspect of the invention provides a toy block and one or more other toy blocks, the block being stackable atop the other block(s) wherein one or both of a bottom of the block and respective tops of the other block(s) includes inclined portions arranged such that horizontally driving the block, in any direction, relative to the other block(s) elevates the block whereby the block is stably retained; and one or more of the blocks includes a blackboard, and/or whiteboard, portion for receiving a user applied image.

BRIEF DESCRIPTION OF THE DRAWINGS Various exemplary arrangements will now be described by way of example only with reference to the accompanying drawings in which:

Figures 1 a to 1f illustrate a main block;

Figures 2a to 2f illustrate a half block;

Figures 3a to 3f illustrate a half block; Figures 4a to 4f illustrate a quarter block;

Figure 5 is an exploded view of stacked blocks;

Figure 6 is an exploded view of stacked blocks;

Figure 7 is a perspective view of stacked blocks;

Figure 8 is a perspective view of a block; Figure 9a is a perspective view of a block; Figure 9b is a perspective view of a block in situ; Figure 10a is a perspective view of a block; Figure 10b is a perspective view of a block in situ;

Figures 1 1 to 14 are perspective views of stacked blocks and accessories; Figure 15 is a perspective view of stacked blocks;

Figure 16 is a perspective view of the blocks of Figure 12 being partially disassembled to reveal concealed images;

Figure 17 is a perspective view of assembled blocks; Figure 18 is a perspective view of assembled blocks; and Figure 19 is a perspective of moulds and stacked blocks formed in the moulds.

DETAILED DESCRIPTION OF THE DRAWINGS

Figures 1 to 7 illustrate a collection of blocks in which main block 10 is the primary building unit. A main block 10 is illustrated in various orientations in Figures 1 a to 1f. Main blocks 10 in their upright, stacking, position are illustrated in Figures 5, 6 and 7. Each main block 10 is configured to be stacked atop one or more other main blocks. The top 12 and bottom 13 are shaped so that the main block can optionally be stacked atop a single other main block, or stacked atop two other main blocks. The block 10 includes four vertical side walls 14A, 14B, 14C & 14D (Figures 1 e and 1f). The sidewalls are vertical and perpendicularly connected to define a long rectangular horizontal cross section of the block. The wider (or long) side walls 14A & 14C are twice as wide as the narrower (or short) side walls 14B & 14D. The sidewalls 14A, 14B, 14C & 14D terminate at the top 12 in edges 16A, 16B, 16C & 16D (Figure 5).

The end points 18A, 18C of the long edge 16A at respective corners of the block are at a common height. Between its end points 18A, 18C the long edge 16A rises and falls a distance to define a central high point 18B a distance above the end points 18A, 18C. The end points 20A, 20C of the long edge 16C at the other two corners of the block are at a common height level with high point 18B. Between its end points 20A, 20C the long edge 16C falls and rises a distance to define a central low point 20B. The low point 20B is at the same height as end points 18A, 18C. Short edges 16B, 16D fall from the higher end points 20A, 20C down to the lower end points 18A, 18C.

The edges 16A, 16B, 16C & 16D bound a top surface 12A made up of inclined portions the purpose of which will be described. In block 10 the top surface is smoothly curved, although in other variants it may be faceted. The top 12 and bottom 13 are symmetrical about a horizontal central plane of the block. For example the points furthest from the plane of symmetry, high points 18B, 20A & 20C of the top 12, symmetrically correspond to the low points 22B, 24A & 24C of the bottom 13 (Figures 1 e and 1f). A variant of the described block may have the bottom 13 rotated 180° about a vertical axis such that the block has a constant vertical thickness. The top 12 and bottom 13 have a complementary form for aligned vertical stacking. The low points 22B, 24A & 24C of the bottom 13 of a block 10 are shaped to be received within low points 18A, 20B & 18C of an underlying block such that the bottom 13 mates with the top 12 of the underlying block. Under its own weight the block 10 tends to slide downwardly along the cooperable inclined portions of the bottom 13 and top 12 towards an aligned position in which it is in register with the underlying block. Thus, the block need not be accurately placed meaning that children not yet dexterous enough to interlock various existing blocks may simply and accurately stack the blocks.

Moreover blocks so stacked are stable. A horizontal force in any direction on the block is resisted by the block riding up the same cooperable inclined portions which aid in its installation. By way of example: A force applied centrally and perpendicularly to a side wall 14A of a block is resisted by that block tending to ride upwardly along an inclined portion, of the surface 12A of an underlying block, rising from the underlying block's low point 20B to its high point 18B. The described blocks are workable with relaxed manufacturing tolerances and do not include projecting studs or keys at risk of shearing. They are also easier to clean than various pre-existing blocks.

The concavo-convex surfaces of the block 10 are shaped for substantially conformal fits with vertically adjacent blocks. Other variants of the block are possible. By way of example, a block having a top 12 as described may have a bottom 13 comprising three vertical pins locatable within low points 18A, 20B & 18C of an underlying like block.

Whilst aligned vertical stacking is possible, it is preferred that blocks be offset relative to the underlying blocks to form a brick pattern in which each block cooperates with two underlying blocks. For this purpose, the surface 12A and its long edges 16A, 16C represent a single unit of a repeating pattern. Each of the edges 16A, 16C has an approximately sinusoidal profile (i.e. shape in the vertical plane) rising and falling to define its high and low points. Other repeating patterns are possible.

The profiles of the edges 16A, 16C have a common pitch and amplitude but are horizontally offset in a direction parallel to the long side wall 14A by half a pitch. In this embodiment the pitch corresponds to the horizontal length of the long side walls 14A, 14C. Longer blocks are possible, but it is preferred that the horizontal length of the blocks be a discrete multiple of the pitch of the repeating pattern for convenient stacking in multiple orientations. The illustrated block 10 is referred to as an osteomorphic block for the bone like appearance of the face 14C (Figure 1f).

Each end of the top 12 terminates in a respective edge 16B, 16D. The edges 16B, 16D have an identical shape and are horizontally aligned. When a like block 10A is placed alongside the block 10 in the same orientation as in Figure 5 the edge 16D of block 10 aligns with the edge 16B of block 10A to define a step free transition between the blocks.

In this embodiment along each of the edges 16A, 16B, 16C & 16D the surface 12A is instantaneously horizontal in a direction normal to that edge. By way of example: every vertical cross section parallel to long side wall 14A is horizontal at the edges 16B, 16D whereby transition between the blocks 10, 10A is not only step free but smooth (in contrast to a possible angular transition).

When the blocks are so positioned, portions of the surface 12A adjacent the edge 16D together with portions of the block 10A adjacent its edge 16B define a surface corresponding in shape to the centre of surface 12A but rotated by 180° about a vertical axis. Accordingly the low point 18B is adapted to receive a low point 22B of a further block (not shown) such that the further block is stacked atop, and cooperates with each of, blocks 10, 10A to form a brick like pattern. The further block is offset by half a pitch relative to blocks 10, 10A so that it is centred above the interface of blocks 10, 10A. The short edges 16B, 16D also have an approximately sinusoidal profile. This profile is of the same height and pitch as the profile of the long edges 16A, 16C. This property allows the block 10 to form a smooth step free transition with a horizontally adjacent perpendicular block. In Figure 5 the block 10 sits horizontally adjacent a like block 10B which is rotated at 90° relative to the block 10. The short edge 16B of the block 10 forms a smooth, step free, transition with an end portion of the edge 16A of block 10B.

Also, like the transition between the blocks 10, 10A, the transition between blocks 10, 10B defines a surface corresponding in shape to the centre of surface 12A but rotated by 180° about a vertical axis. Accordingly the low point 18C is adapted to receive a low point 22B of a further block 10C (Figure 6) such that the further block 10C is stacked atop, and cooperates with each, of blocks 10, 10B.

Preferred forms of the surfaces 12, 13 are described, using the Cartesian coordinate system shown in Fig. 8 by the following equations: z ₁₂ (x,y) = Ahf(x)f(y) + h, (1 ) zi ₃ (x,y) = Ahf(x+a)f(y) - h (2) Here 2a denotes the length of the block and 2h is its height at half way along a narrow face. The degree of interlocking (or the depth of the surface profile) is governed by the parameter Ah < h. The function f(x) is an arbitrary periodic function that satisfies the following conditions: f(x) f(-x); (3) f(x) f(x+2a); (4) f(0) 1 ; (5) f(a) -1 ; (6) df/dx = 0 for x = 0 and x = a (7)

Figures 2, 3 and 4 illustrate smaller blocks cooperable with the blocks 10. Blocks 26, referred to as half blocks, have a form corresponding to the top half of the block 10. Blocks 26 each present a planar surface and a contoured surface. The planar surface may be seated on a horizontal surface such that the contoured surface faces upwards to cooperate with further blocks as Figure 6. In this way the blocks 26 together form a foundation. Alternatively, the contoured surface may cooperate with underlying blocks such that the planar surface defines a horizontal top as in Figure 7.

Blocks 28, also referred to as half blocks, have a form corresponding to a half of a block 10 as if a block 10 were cut vertically through its centre in a direction parallel to its narrow side walls 14B, 14C. The blocks 28 are useful for filing a void at the end of a course of blocks 10 offset to the underlying blocks (Figure 7).

Blocks 30, referred to as quarter blocks, have a form corresponding to a block 28 cut horizontally through its centre. Blocks 30 are useful for filing a void at the end of a course of blocks 26 offset to the underlying blocks (Figure 7). Combinations of blocks 26, 28 and/or 30 can be used in place of blocks 10. Figure 7 illustrates a combination for two blocks 28 and four blocks 30 replacing two blocks 10. Preferably the blocks are brightly coloured, and most preferably the blocks are colour coded, e.g. blocks 10, 26, 28 and 30 may be red, blue, yellow and green respectively.

Using the described blocks, stable structures can be formed whilst omitting selected blocks so as to leave voids. Figure 7 illustrates the omission of a block 10 from an otherwise continuous pattern of blocks to define a window 32. Figures 6 and 7 illustrate blocks 10 stacked to form a single vertical layer. Other structures may be formed from multiple layers of blocks. The strength of such structures may be improved by tying adjacent layers. For this purpose a "double block" 10D is desirably employed (Figures 9a, 9b, 10a, 10b) although other tying arrangements are possible.

The double block 10D is an integral body equivalent to two blocks 10 bonded, at their wide faces 14A with those faces in registration, so that its top and bottom 12D, 13D each present a central convex portion.

Figure 9b illustrates double block 10D in situ interconnecting block layers 48A, 48B. Figures 10a, 10b illustrate an alternative double block 10E equivalent to two blocks 10 bonded, at their wide faces 14C with those faces in registration, to present a central concave portion top and bottom.

A double block may be formed of two blocks bonded, or otherwise fastened, together, but it is preferred that the double blocks be integrally formed. Figures 1 1 to 14 illustrate accessories complementary to the above blocks. Figure 1 1 illustrates a modified quarter block 30' carrying a flag 32. Figure 10 illustrates a window 34 having an exterior shaped to fit within a regular pattern of blocks 10. Figure 13 illustrates a roof member 36 in the form of a four sided pyramid having a concentric square element projecting downwards from its base. The square projection is dimensioned to fit within a square tubular structure formed of blocks 10, 26. Figure 14 illustrates two modified half blocks 28' each carrying a respective gate 38.

Figures 15 and 16 illustrate a three dimensional jigsaw 40, referred to as a pictocube, formed of the above blocks. The jigsaw 40 has the form of a cube. The three faces visible in Figure 15 each present a respective image in the form of a picture (i.e. a yacht with stars, a plane with clouds and a car with flames). Respective blocks each carry respective image portions such that the blocks may be brought together to form the images. The illustrated embodiment includes blocks carrying image portions for forming a concealed image in the form of a compass. The blocks may be partially disassembled to reveal the concealed image. Preferably the blocks are arranged to present a series of puzzles sequentially solvable to form a finished three dimensional object, e.g. from a collection of loose blocks the correct blocks must be selected and stacked to form the compass, then the correct blocks selected and stacked to form the yacht and so form the pictocube 40. Figure 16 also illustrates a collection of blocks interlocked horizontally and showing an image of a yacht. Whilst the described blocks are vertically stackable, as in Figures 6 and 7, the described geometry is also advantageous when the blocks are horizontally interlocked. When held within a frame (or other peripheral restraint) the horizontally interlocked blocks are securely held together permitting the collection of blocks to be handled as a unitary body. In addition, or as an alternative to the peripheral constraint, the blocks may be magnetically cooperable so as to be held in relative disposition.

Desirably the image portions may be applied by a user of the blocks. For example, a child may assemble the blocks and then apply an image spanning multiple blocks. The blocks may then be disassembled and reassembled in the manner of a 'draw your own jigsaw'. For this purpose the image portions are preferably readily erasable. This may be achieved by careful selection of the surface treatment of the blocks and/or the marking implement. By way of example, the blocks may have a dark matt finish as in a blackboard (also known as a chalk board) and be supplied along with marking implements in the form of colored chalk pieces. Of course other complementary pairings of surface treatments and marking implements are possible.

The block 10 described above is configured to cooperate with other like blocks. This allows a collection of like blocks to be assembled in a many different ways. Thus a child may design their own miniature dwellings and other structures. Alternative variants of the blocks may be configured to cooperate with dissimilar blocks. By way of example, a collection of blocks may be configured to be stacked in a unique arrangement so as to present an entertaining challenge in identifying mating blocks. Image portions carried by the blocks may assist with this identification.

In a variant of the blocks (not shown) each block may respectively carry one (or more than one) letter, numeral or other symbol whereby the blocks may be stacked to form various words or numbers, or an alphabetical, numerical or other sequence. Such blocks may be employed in word and/or number games, e.g. games involving mathematical problem solving.

Such blocks are preferably configured to be stacked in various different relative orientations whereby a user of the blocks may select the orientation to form a user selected image (i.e. word, number or sequence). Alternatively, the blocks may be configured to be stacked in a single unique relative orientation to reveal a predetermined image. Examples of the described blocks may carry respective letters for use in a Scrabble™-like game across the faces of a pictocube.

The blocks of Figures 1 to 16 are intended for an infant. For this purpose they desirably have a volume of about 0.3L and a weight of about 0.07kg. This size and weight is convenient for manipulation by an infant without being a choking hazard. 1 L is considered to be a practical limit above which infants have difficulty gripping the blocks. Similarly 0.2kg is considered a practical limit for gripping by an infant.

Figures 17 and 18 illustrate blocks 10", 26", 28" and 30" for older children. These blocks are scaled up variants of blocks 10, 26, 28 and 30. Desirably the blocks have a volume between about 20L and about 120L, preferably about 70L. This is considered big enough for a manageable number of blocks to be assembled into "child scale" structures (e.g. cubby houses) yet not so big that children have difficulty lifting the blocks. Whilst older children are stronger than infants, it is desirable that the blocks should not be too heavy. 3kg is considered a desirable limit for ready manipulation by a child. To achieve this desired size and weight the blocks are preferably formed of foam.

Figure 19 illustrates moulds 42A & 42B for moulding a mouldable material such as snow to form a block. Blocks from these moulds may be used to construct a stable igloo 44.

The described blocks have an aesthetically pleasing appearance which is an inviting departure from conventional right angled six sided blocks. Preferred forms of the blocks have a minimalist design, combine interlocking with versatility of assembly, and have few protrusions (and so are unlikely to cause injury). Moreover the unusual shapes promote abstract and creative thinking which holds interest and has developmental benefits. Similar abstract and creative thinking can be promoted in a computer game requiring a user to interlock graphical representations of the blocks. Desirably a user may be rewarded for successfully interlocking the representations. The reward may take the form of a score, progression in the game (e.g. advancing to a next level), a physical or virtual prize, and/or a continuance of the game (e.g. the game may be terminated if the blocks are not successfully stacked).