A toy building block and a toy construction system

Abstract

A cuboidal toy building block comprising: six side walls (11, 12, 21, 22, 31, 32) arranged in three pairs of opposing side walls (11, 12, 21, 22, 31, 32); a first main through opening (10) having a first central axis (X) perpendicular to a first pair (11, 12) of opposing side walls; a second main through opening (20) having a second central axis (Y) perpendicular to a second pair (21, 22) of opposing side walls; a third main through opening (30) having a third central axis (Z) perpendicular to a third pair (31, 32) of opposing side walls; wherein the central axes (X, Y, Z) intersect each other at a first common intersection point (P1); and at least four primary threaded through openings (41) in each side wall, arranged symmetrically around each main through opening (10, 20, 30) between the main through opening (10, 20, 30) and each of the edges of the side wall.

Description

TECHNICAL FIELD

[0001] The present invention relates to a toy building block and to a toy construction system.BACKGROUND

[0002] Toy construction sets have long been popular among children and parents, promoting creativity, spatial reasoning, and fine motor skills. Traditional building blocks, typically made of wood or plastic, are limited in their connectivity and versatility, often only allowing for stacking or simple interlocking. These conventional blocks frequently suffer from several notable drawbacks, which hinder their utility and appeal.

[0003] One common issue with traditional building blocks is their limited interconnectivity. Many sets feature blocks that can only be connected in a single orientation, such as stacking vertically. This restriction severely limits the variety and complexity of structures that can be built. For example, popular interlocking bricks, such as those described in U.S. Pat. No. 3,005,282, connect primarily through male and female connectors on their upper and lower surfaces, constraining constructions to a single dimension and reducing the potential for creative, multi-directional designs.

[0004] Another limitation of traditional blocks is the visibility and structural role of the connecting mechanisms. In many sets, the connectors are not only visible but also integral to the structure stability. This often results in less aesthetically pleasing models, as the connectors detract from the overall appearance. Additionally, the fixed nature of these connectors can make assembly and disassembly cumbersome, reducing the enjoyment for users.

[0005] Some modern toy construction sets, such as those using rod and connector systems (as described in U.S. Pat. No. 5,238,438), allow for more diverse three-dimensional structures. However, these sets typically result in skeletal designs that lack the solidity and realism of traditional blocks. Furthermore, these designs often do not resemble everyday objects, limiting their educational value in demonstrating construction aspects.

[0006] Magnetically connected blocks and slotted card systems offer alternative methods of construction but come with their own sets of challenges. Magnetic connections can be weak, making it difficult to build stable, larger structures. Slotted card systems, while innovative, are often limited by the shape and size of the components, restricting the variety of possible constructions.SUMMARY OF THE INVENTION

[0007] There is a need to provide a toy building block with improved versatility and interconnectivity, enabling the construction of more complex and varied structures.

[0008] In one aspect, the invention relates to a cuboidal toy building block comprising six side walls arranged in three pairs of opposing side walls. The building block has three main through openings, each having a central axis perpendicular to one pair of opposing side walls. The central axes of these main through openings intersect at a common intersection point. Additionally, each side wall includes at least four primary threaded through openings arranged symmetrically around each main through opening, positioned between the main through opening and the edges of the side wall.

[0009] The arrangement of the main through openings along three perpendicular axes intersecting at a common point allows for multi-directional connectivity of building blocks. This enables the construction of complex and varied structures that are not limited to a single dimension.

[0010] The symmetrical arrangement of at least four primary threaded through openings around each main through opening ensures uniform distribution of connection points. This design provides multiple secure attachment points for screws or other fasteners, achieving the structural integrity and stability of assembled constructions. The symmetry also allows for consistent and predictable assembly, reducing the likelihood of misalignment between the building blocks and increasing ease of secure connection between the building blocks.

[0011] Depending on the size of the block or the specific design requirements, a greater number of primary threaded openings can be included, such as five, six, seven, eight, nine, ten, or more primary threaded through openings for larger blocks.

[0012] The threaded through openings are designed to be compatible with a range of screws and other fasteners. This compatibility allows for diverse construction possibilities, including both rigid and pivotable connections. The ability to use different types of connectors further extends the creative potential and functional applications of the building blocks.

[0013] The design of the building block, with its intersecting main through openings and symmetrically arranged threaded through openings, maintains a clean and aesthetically pleasing appearance. This design at least partially conceals the connecting mechanisms within the structure, resulting in more visually appealing models.

[0014] The intersecting main through openings and the symmetrical arrangement of threaded through openings contribute to the overall structural integrity and stability of the assembled constructions. This design ensures that the blocks can support more substantial and complex structures without compromising stability.

[0015] The building block is designed to be manufactured using 3D printing technologies, which allows for precise and consistent production of complex shapes and features. This method of production ensures high accuracy and quality, enabling the creation of durable and reliable building blocks that can withstand repeated use and assembly.

[0016] The building block may comprise at least four secondary threaded through openings in each side wall, arranged symmetrically around each main through opening between the primary threaded through openings. This provides additional connection points, further enhancing the structural integrity and stability of the assembled constructions. This increased number of connection points allows for more intricate and robust designs, making the building blocks suitable for constructing larger and more complex structures. The additional threaded through openings also offer greater flexibility in assembly, enabling users to create more varied and customized designs.

[0017] Depending on the size of the block or the specific design requirements, a greater number of secondary threaded openings can be included, such as five, six, seven, eight, nine, ten, or more threaded through openings for larger blocks.

[0018] The threaded through openings comprise at least a fragment of a single thread turn. In other words, the threaded through openings comprise at least a fragment of a ridge in the form of a helix.

[0019] The width of the main through openings can be equal to one-third of the width of the building block. That ensures a balanced and proportional design, which facilitates the alignment and connection of multiple blocks. The consistent ratio between the width of the main through openings and the width of the building block simplifies the design process and enhances the ease of assembly.

[0020] The building block may comprise a protrusion located on the inner wall of each main through opening. It compensates for dimensional inaccuracies of connecting elements, such as plastic or wooden beams and shafts, arising during the production process. The protrusion ensures a tight fit connection between the building block and the connecting elements, enhancing the stability and durability of the assembled structures. This is particularly useful when using materials that may expand or contract due to environmental factors, such as humidity or temperature changes.

[0021] The protrusion may have the form of an extra layer of material deposited on the inner side of the main through openings. The extra layer may be formed as single, double, or triple print layers. The protrusion may have the shape of an arc. The radius of the arc may be equal to the width of the building block side wall. For example, the protrusion, in the shape of an arc, can compensate for inaccuracies of 1 / 40 of the width in the diameter of the shaft or the width of the beam (for a width of 60 mm, this is 1.4 mm).

[0022] The protrusion may also have the form of elongated bulges arranged parallel to the central axis of the main through opening.

[0023] The protrusion may also be defined as a pressure element, providing a tight fit connection between the building block and the connecting elements.

[0024] The main through openings may have a square shape. It provides a uniform and predictable connection interface, which simplifies the design and assembly process. The square shape allows for precise alignment of the connecting elements, ensuring a secure and stable connection without a risk of rotation of the connecting element or the building block along the longitudinal axis of the connecting element with a square cross section. Nevertheless, the main through openings may also accommodate other connecting elements having other cross sections, such as rounded connecting elements (such as shafts), if there is a need for rotation of the building block around the connecting element.

[0025] The building block may comprise longitudinal indentations located at the inner corners of the main through openings. It protects against material shrinkage during the printing process, which can lead to rounding of the 90-degree angles of the square openings. The indentations ensure that the connecting elements, such as beams with square cross sections, can be easily inserted and securely held in place. The longitudinal indentations located at the inner corners of the square main through openings may also be defined as corner grooves. The longitudinal indentations may have a diameter of 1 mm (regardless of the adopted dimensions of the building block.

[0026] The main through openings can be circular. It allows for rotational movement of the connecting elements of any cross section, enabling the construction of dynamic and movable structures. The circular openings can accommodate shafts and other cylindrical connectors, providing greater flexibility in design and assembly. This is particularly useful for creating structures with rotating or pivoting components, such as wheels or hinges.

[0027] The main through openings may have a polygonal shape. Such a feature offers a unique and versatile connection interface, which can accommodate a variety of connecting elements with matching polygonal cross sections. The polygonal shape provides multiple flat surfaces for different, but specified angular positions of connecting elements or building blocks.

[0028] At least one edge of the building block can be rounded. It enhances the safety and usability of the building blocks, particularly for younger children. The rounded edges reduce the risk of injury from sharp corners, making the blocks safer to handle and play with.

[0029] In a particular embodiment, the building block may have the form of a cube, with the central axes of the main through openings coinciding with the symmetry axes of the building block. This provides a highly symmetrical and balanced design, which simplifies the alignment and connection of multiple blocks. The cubic form ensures that the blocks can be easily stacked and connected in any orientation, enhancing the versatility and ease of assembly.

[0030] The primary threaded through openings can be arranged on the axes of symmetry of the side walls, with each opening positioned on the opposite side of the respective main through opening. This ensures a uniform distribution of connection points, which enhances the structural integrity and stability of the assembled constructions. The symmetrical arrangement reduces the likelihood of misalignment and ensures that the blocks can be securely connected in any orientation.

[0031] In a particular embodiment, the building block may have an elongated form, such as it may have a length two times longer than its width. This design provides a larger and more versatile building block, which can be used to create more extensive and complex structures. The elongated form allows for the construction of longer spans and larger surfaces, making the blocks suitable for building furniture and other functional items.

[0032] The main openings may have a longitudinal shape. The longitudinal main openings provide additional versatility in the location of the connecting elements, further enhancing the versatility and structural integrity of the assembled constructions.

[0033] The elongated building block may further comprise a fourth main opening with a central axis perpendicular to a pair of opposing side walls, intersecting the second central axis and parallel to the first central axis. This provides an additional connection point, which enhances the versatility and complexity of the assembled structures. The fourth main opening allows for multi-directional connectivity, enabling the construction of more intricate and robust designs. This feature also increases the flexibility of the building blocks, allowing users to create more customized and varied structures.

[0034] The elongated building block may further comprise a fifth main opening with a central axis perpendicular to a pair of opposing side walls, parallel to the third central axis, and intersecting the fourth and second central axes at a second common intersection point. This provides an additional connection point, enhancing the versatility and complexity of the assembled structures. The fifth main opening allows for even more multi-directional connectivity, enabling the construction of highly intricate and robust designs. This feature also increases the flexibility of the building blocks, allowing users to create more customized and varied structures.

[0035] The building block may have two rows of threaded through openings located between the first and fourth main through openings. This provides additional connection points, enhancing the structural integrity and stability of the assembled constructions. The double rows of threaded through openings allow for more secure and robust connections, making the building blocks suitable for constructing larger and more complex structures. This feature also increases the flexibility of the building blocks, allowing users to create more varied and customized designs.

[0036] The building block may have two rows of threaded through openings located between the third and fifth main through openings. This provides additional connection points, enhancing the structural integrity and stability of the assembled constructions. The double rows of threaded through openings allow for more secure and robust connections, making the building blocks suitable for constructing larger and more complex structures. This feature also increases the flexibility of the building blocks, allowing users to create more varied and customized designs.

[0037] The building block can be made using a 3D printing process. This allows for precise and consistent production of complex shapes and features, ensuring high accuracy and quality. The 3D printing process enables the creation of durable and reliable building blocks that can withstand repeated use and assembly. This manufacturing method also allows for rapid prototyping and customization, making it possible to produce building blocks with unique and intricate designs. Additionally, 3D printing reduces material waste and production costs, making the building blocks more environmentally friendly and cost-effective.

[0038] In another aspect, the present invention relates to a toy construction system comprising at least two building blocks as described herein and at least one first screw having a thread compatible with the threaded through openings for connecting the building blocks. The first screw is useful for assembly and disassembly of the building blocks. This allows users to quickly and securely connect multiple blocks, facilitating the construction of more complex structures. The compatibility of the screw thread with the threaded through openings ensures a tight fit, reducing the risk of structural instability. This advantage is particularly beneficial for creating robust and durable models that can withstand repeated use and manipulation.

[0039] The construction system may further comprise at least one second screw with a pointed end and at least one wooden or plastic connecting element for connecting building blocks by inserting the connecting element into the main through opening and securing it with the second screw. The use of the second screw with a pointed end and wooden or plastic connecting elements introduces the ability to create semi-permanent connections that can be easily adjusted or modified. This feature is advantageous for prototyping and iterative design processes, allowing users to experiment with different configurations before finalizing their structures. The pointed end of the screw ensures a secure grip on the connecting element, enhancing the overall stability of the construction.

[0040] The second screw may have a pointed conical end. When the building blocks are connected by means of connecting elements in the form of wooden beams or shafts, the pointed conical end penetrates the material of the beam or shaft, maintaining it in a fixed position. This functionality is especially useful when prototyping new structures. When the structure has its final design, it may be disassembled. The second screw with a pointed, hard end, when tightened, leaves a visible mark on the wooden beam or shaft. Thereafter, in the beams or shafts, at the locations of the marks, through holes may be drilled. The structure may be assembled again, and instead of short pointed-ended second screws, the longer first screws with flat ends are used, which go through the beam, securing it in the desired position and providing increased strength and stiffness to the structure. Preferably, the through holes are offset from the main axis of symmetry of the beam by a distance x to provide tension to the screw. The material of the screw is slightly flexible and bends in the region of the opening, providing additional tightness of the connection and stiffness to the structure. The distance x may be equal to 1 / 30A (for example, about 2 mm). Due to this, various functional structures made of the building blocks maintain the required level of stiffness to fulfill their tasks. Moreover, due to the screw flexibility, the structure can absorb momentary abnormal loads (e.g., bending of the leg caused by moving the table or rocking on a chair).

[0041] The second screws with the pointed end may also be used in connection with shafts having a circumferential groove. The pointed end of the screw enters the circumferential groove, preventing the shaft from falling out of the building block while maintaining its freedom to rotate.

[0042] The construction system may further comprise at least one connecting element with at least one through hole for connecting building blocks by inserting the connecting element into the main through opening and securing it with the first screw. This allows forming strong structures. On the other hand, when using rounded connecting elements, this allows for the creation of pivotable connections between building blocks. This feature enables the construction of dynamic and movable structures, such as rotating joints or hinges, which are not possible with traditional building blocks. The ability to create pivotable connections adds a new dimension of interactivity and functionality to the toy construction set, enhancing its educational value by demonstrating mechanical principles.

[0043] Alternatively, third screws may be used, which have a split end. The split end may be formed by making a notch or slit at the initially flat end of the screw. Thereafter, the two halves of the end may be slightly bent outwardly, particularly under increased temperature. Such treatment results in the split end tending to maintain its outwardly bent position and prevents the self-unscrewing of the third screw.

[0044] Depending on the material of the third screw, a different angle of outward bending may be required. The more flexible the material, the wider the notch should be to generate greater internal stresses that oppose the forces created during usage of the structure (e.g., due to vibration). When screwing the third screw with a split or expanded end into a threaded through opening, the notch temporarily closes, and when it reaches the open chamber of the building block, it expands like an expansion pin, returning to the default expanded shape induced during thermal treatment. The open chamber may be another threaded through opening located on the other side of the building block.

[0045] Preferably, the screws have a diameter of 1 / 3A, a thread pitch of 1 / 2A, and a head diameter of 0.65A. Such dimensions allow them to self-screw under the influence of gravity. The screws only require final tightening at the head height (the threaded through opening in the building block for the screw head has a larger diameter by 0.2 mm, which considering the accuracy of 3D printing from plastics generates sufficient fit and screw holding).

[0046] The second screw may have a length equal to 0.4A. The first and third screws may have lengths equal to 0.9A and 1.55A or longer.

[0047] The longer screws may be used to directly connect two building blocks together, without any connecting elements.

[0048] The connecting element may have a longitudinal through hole. This provides the capability for longitudinal and pivotable movement between connected building blocks. This allows for the creation of telescoping structures or adjustable-length components, adding versatility to the construction set. The ability to adjust the length of connections dynamically enhances the user's ability to create custom-sized structures tailored to specific needs or preferences.

[0049] The connecting element may have two through holes located at its ends. This facilitates the creation of stable and secure connections between multiple building blocks. This feature allows for the construction of more complex and interconnected structures, such as frameworks or scaffolding, by providing multiple attachment points. The dual through holes ensure that the connected blocks remain aligned and stable, even under load or stress. This enhanced stability and structural integrity are particularly beneficial for building larger and more intricate models.

[0050] In a particular embodiment, the connecting element is a wooden beam with two through holes located at its ends. Using wooden beams with through holes as connecting elements introduces a natural and sustainable material option for the construction set. Wooden beams provide a unique aesthetic and tactile experience, appealing to users who prefer natural materials over plastic. The through holes in the wooden beams ensure secure connections with the building blocks, maintaining the structural integrity of the assembled models. This feature also allows for the integration of traditional woodworking techniques with modern toy construction, offering a blend of old and new that is not available in conventional building block sets. Wooden beams can be also easily replaced by users themselves in case they are damaged. Furthermore, users may easily produce wooden connecting elements on their own in order to adjust the length of the connecting element to needs for a particular construction.

[0051] In the case of connecting elements in the form of beams, the diameter of the beam (shaft) with a circular cross section, as well as the transverse dimensions of the square beams, is preferably lower than 1 / 3A. Under ideal laboratory conditions, a perfect tight fit can be achieved for components manufactured from hard materials (e.g., steel); however, in the case of wooden or plastic connecting elements, dimensional accuracy can be as low as-2%A. Gaps in the construction caused by the use of connecting elements with lower dimensions than the dimensions of the main through openings are compensated by protrusions.

[0052] The connecting elements may be of any length equal to or greater than 2 / 3A, as this is the minimum distance that allows for two adjacent blocks to be connected, regardless of whether they have pre-drilled through holes (for first or third screws) or not (for use with second screws).

[0053] Preferably, the cross-sectional shape of the connecting element matches the shape of the main through openings.

[0054] The connecting elements in the form of beams and shafts are responsible for carrying the greatest loads in utility structures such as chairs or tables. In such structures for demanding applications (furniture), the entire weight of the person or structure rests on the beams, while the building blocks are only responsible for maintaining them properly held in place. The applied force (e.g., human weight) is transferred along the beam directly to the floor. The connecting elements in the form of beams and shafts allow for connecting multiple building blocks.

[0055] The connecting elements may also have the form of 3D printed plastic connectors with rounded ends. Such connecting elements allow for pivotable connection between the building blocks.

[0056] A first connector type is used for connecting two building blocks such that their relative movement is restricted.

[0057] A second connector type is used for connecting two building blocks such that their relative pivotal movement is possible.

[0058] A third connector type is used for connecting two building blocks such that their relative pivotal and longitudinal movement is possible. The third connector type has a longitudinal through hole, which provides longitudinal movement. The third connector type may also comprise two circular through holes with the axes perpendicular to the longitudinal through hole, located at its ends. This provides a double functionality of the connector - first pivotal functionality, same as for second type connectors, and second pivotal and longitudinal displacement functionality.

[0059] A fourth connector type features two through holes for securing the connector with screws and four elastic bulges for locking the connector into the building block without screws. The axes of the through holes are perpendicular to the axes of the bulges, respectively. The fourth connector type is suitable for connecting building blocks with main through openings in the shape of a square. Utilizing the fourth connector type for connecting the building blocks via the bulges allows for rapid connection and disconnection of blocks, which is advantageous when prototyping new structures.

[0060] The building block may comprise cover plates for covering the main through openings and the threaded through openings. The cover plate has mounting elements corresponding to the shape of the main through openings, allowing the cover plate to be snap-fitted into the main through opening. The cover plates serve an aesthetic function, enabling the main through openings of the building blocks to be closed after the structure is completed. Additionally, the cover plates may have printed elements such as texts or graphics, or may function as a smooth surface for a sticker.

[0061] The toy building block and other elements of the toy building set can be manufactured by 3D printing, using technologies such as FDM (Fused Deposition Modelling) and SLS (Selective Laser Sintering), depending on the desired strength of the elements and their applications. Each of these technologies uses specific materials that have unique properties and applications (for screws, needed flexibility, and for cubes, stiffness).

[0062] FDM is the most common 3D printing technology, which involves melting and extruding a thermoplastic filament through a nozzle that applies the material layer by layer. The main materials used in FDM printing technology are: PLA (Polylactide): A biodegradable plastic that is easy to print and has a low melting point (about 180-220°C). It is relatively stiff and brittle, making it ideal for prototypes and decorative models. ABS (Acrylonitrile-Butadiene-Styrene): A tough plastic that is resistant to impact and high temperatures (approximately 220-250°C). It is more durable than PLA but more challenging to print due to its tendency to shrink and warp. PETG (Polyethylene Terephthalate Glycol): Combines the properties of PLA and ABS, being strong, flexible, resistant to chemicals, and easier to print than ABS. It is used at temperatures of about 220-250°C.

[0063] Another group of materials includes fiber-reinforced materials such as: PACF (Carbon Fiber Reinforced Polyamide): Offers high mechanical strength, stiffness, temperature, and abrasion resistance. It is ideal for automotive components, machine parts, and equipment housings. PAGF (Glass Fiber Reinforced Polyamide): Provides increased strength and stiffness with good impact resistance. It is used for structural components. PLA CF (Carbon Fiber Reinforced Polylactide): Offers better rigidity and strength than standard PLA while maintaining ease of printing. ABS CF (Carbon Fiber Reinforced Acrylonitrile-Butadiene-Styrene): Provides higher mechanical strength, stiffness, impact, and temperature resistance. PC CF (Carbon Fiber Reinforced Polycarbonate): Offers high strength and stiffness, along with temperature and impact resistance.

[0064] The SLS (Selective Laser Sintering) process uses a laser to sinter polymer, metal, or ceramic powders to form solid layers. Although the SLS printing process is slow and expensive, it can be very useful for creating load-bearing structures such as tents and store shelving. With these materials, it is possible to create more durable, strong, and precise components. The main materials used in the SLS printing technology are: PA (Polyamides, e.g., PA12, PA11): Known for high mechanical strength, impact, and chemical resistance. TPU (Thermoplastic Polyurethane): A flexible powder used for manufacturing parts requiring flexibility and abrasion resistance. Composites: Powders reinforced with glass or carbon fibers, which increase the strength and stiffness of printouts. Metals: Such as stainless steel, aluminum, and titanium, used to print metal parts in advanced engineering applications.

[0065] The elements of the toy building set can also be produced by injection molding and traditional methods such as machining. However, due to the complex shapes, these methods are very time-consuming and problematic, though feasible.

[0066] The presented toy construction set may be used for constructing various structures such as chairs, tables, racks, as well as toy structures such as houses, boxes, or vehicles.BRIEF DESCRIPTION OF DRAWINGS

[0067] The present invention is shown by means of preferable embodiments in a drawing, wherein: Fig. 1A presents a first embodiment of the building block in an isometric view; Fig. 1B presents the first embodiment of the building block in a front view; Fig. 2A presents a second embodiment of the building block with a protrusion in a front view; Fig. 2B presents a fragment of the cubic building block of Fig. 2A in a cross-sectional view; Fig. 2C presents detail D from Fig. 2B; Fig. 3 presents details of the main through opening of the first and the second embodiment of the building block; Fig. 4A presents a third embodiment of the building block, in an isometric view; Fig. 4B presents a fourth embodiment of the building block, in an isometric view; Fig. 5A presents a second screw, in a side view; Fig. 5B presents a first screw, in a side view; Fig. 5C presents a third screw with a divided end, in a side view; Fig. 6 presents a fifth embodiment of the building block, in an isometric view; Fig. 7A presents a sixth embodiment of the building block, in an isometric view; Fig. 7B presents the sixth embodiment of the building block, in a side view; Fig. 7C presents the sixth embodiment of the building block, in a front view; Fig. 8 presents a seventh embodiment of the building block, in an isometric view; Fig. 9 presents an eighth embodiment of the building block, in an isometric view; Fig. 10 presents a ninth embodiment of the building block, in an isometric view; Fig. 11A presents a connecting element in the form of a plastic first connector type; Fig. 11B presents the connecting element in the form of a plastic second connector type; Fig. 11D presents the connecting element in the form of a plastic fourth connector type; Fig. 12A presents an exemplary structure with connecting elements in the form of beams, in a side view; Fig. 12B presents an exemplary structure with connecting elements in the form of beams, in an isometric view; Fig. 13A presents two building blocks with a connecting element in the form of a shaft, in a side view; Fig. 13B presents two building blocks with a connecting element in the form of a shaft, in a cross-sectional view; Fig. 14A presents two building blocks connected by the first connector type in a top view; Fig. 14B presents two building blocks connected by the first connector type in a cross-sectional view; Fig. 15A presents two building blocks connected by the second connector type in a cross-sectional view; Fig. 15B presents two building blocks connected by the second connector type in a front view; Fig. 16 presents building blocks connected by the third connector type in a front view; Fig. 17A presents a wooden beam connecting element in a side view; Fig. 17B presents a cross section B-B from Fig. 17A; Fig. 18A presents a cover plate for square main through openings, in a side view; Fig. 18B presents the cover plate from Fig. 18A, in a front view; Fig. 18C presents the cover plate from Fig. 18A, in a back view; Fig. 18D presents a building block with square main through openings with the cover plate; Fig. 19A presents a cover plate for circular main through openings in a back view; Fig. 19B presents a cover plate for circular main through openings in a side view; Fig. 20 presents an exemplary structure in the form of a chair; Fig. 21 presents an exemplary structure in the form of a rack; Fig. 22 presents an exemplary structure in the form of a desk; Fig. 23 presents an exemplary structure in the form of a table; Fig. 24 presents an exemplary structure in the form of a vehicle; Fig. 25 presents an exemplary structure in the form of a car. DETAILED DESCRIPTION OF EMBODIMENTS

[0068] Figs. 1A-1B present a first embodiment of the toy building block. In the first embodiment, the building block has the form of a cube with six side walls 11, 12, 21, 22, 31, 32 arranged in three pairs 11-12, 21-22, 31-32 of opposing side walls. The building block comprises three main through openings 10, 20, 30 in the shape of a square. Central axes X, Y, Z of the main through openings 10, 20, 30 coincide with the symmetry axes of the building block respectively, which intersect at a first common intersection point P1. Each side wall 11, 12, 21, 22, 31, 32 comprises eight threaded through openings 41, 42 arranged uniformly around each main through opening 10, 20, 30. Eleven of the twelve edges of the building block are rounded. The width d of the main through openings 10, 20, 30 is equal to 1 / 3 of the width A of the building block. The width A of the building block is equal to 60 mm. The main through openings 10, 20, 30 comprise circumferential chamfers 73.

[0069] The first two primary threaded through openings 41 are arranged on the first axis of symmetry S1 of the side wall, each on the opposite side of the respective main through opening 10, 20, 30, and the second two primary threaded through openings 41 are arranged on the second axis of symmetry S2 of the side wall, each on the opposite side of the respective main through opening 10, 20, 30, wherein the axes of symmetry S1, S2 of the side wall are perpendicular to the edges of the respective side wall. The second threaded through openings 42 are arranged between the first threaded through openings 41.

[0070] Figs. 2A-2C present a second embodiment of the building block. The building block in the second embodiment differs from the first embodiment in that it additionally comprises a protrusion 70, located on every inner side wall of each main through opening 10, 20, 30. The protrusion 70 has a shape of an arc and is formed of two layers of 3D print material.

[0071] Fig. 3 presents details of the main through opening of the first and the second embodiment of the building block. The main through openings 10, 20, 30 have longitudinal indentations 71 located at their inner corners. The longitudinal indentations 71 are rounded.

[0072] Fig. 4A presents a third embodiment of the building block. The cubic building block of the third embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are circular.

[0073] Fig. 4B presents a fourth embodiment of the building block. The cubic building block of the fourth embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are polygonal.

[0074] Fig. 5A presents a second screw with a pointed end. The second screw has a length equal to 0.4A, wherein A is the width of the cubic building block and may be equal to 60 mm.

[0075] Fig. 5B presents a first screw having a flat end. The first screw has a length equal to 0.9A.

[0076] Fig. 5C presents a third screw having a divided end. The divided end has two arms 131 which are distanced from each other by a notch. The length of the arms 131 is equal to 0.2A.

[0077] Fig. 6 presents a fifth embodiment of the building block. The building block of the fifth embodiment is in the form of a rectangular cuboid and comprises a first main through opening 10 with a first central axis X, a second main through opening 20 with a second central axis Y, and a third main through opening 30 with a third central axis Z. The central axes X, Y, and Z intersect each other at a first common intersection point P1. The central axis X is equidistant from the fifth side wall 31 and the third side wall 21, the distance being equal to half the width A of the building block. Similarly, the central axis Y is equidistant from the first side wall 11 and the fifth side wall 31, and the central axis Z is equidistant from the third side wall 21 and the first side wall 11, each distance equal to by half the width A of the building block.

[0078] The building block further comprises a fourth main through opening 50 with a fourth central axis X1 perpendicular to a first pair of opposing side walls 11, 12, intersecting the second central axis Y and parallel to the first central axis X. Additionally, it comprises a fifth main through opening 60 with a fifth central axis Z1 perpendicular to a third pair of opposing side walls 31, 32, parallel to the third central axis Z, and intersecting the fourth central axis X1 and the second central axis Y at a second common intersection point P2. The fifth central axis Z1 is equidistant from the first side wall 11 and the fourth side wall 22, and the fourth central axis X1 is equidistant from the fifth side wall 31 and the fourth side wall 22, each by half the width A of the building block. The main through openings 10, 20, 30, 50, 60 are square-shaped with a width equal to one-third of the width A. The third 21 and fourth side walls 22 each have eight threaded through openings 41, 42, while the first 11, second 12, fifth 31, and sixth 32 side walls each have thirteen threaded through openings 41, 42, with rows of three threaded through openings located between the first main through opening 10 and the fourth main through opening 50, and between the third main through opening 30 and the fifth main through opening 60. Eleven of the twelve edges of the building block are rounded.

[0079] Figs. 7A-7C present a sixth embodiment of the building block, which is a rectangular cuboid with a length L twice its width A. This embodiment differs from the fifth embodiment in that the first 11, second 12, fifth 31, and sixth 32 side walls have sixteen threaded through openings 41, 42, with two rows of three threaded through openings 41, 42 located between the first main through opening 10 and the fourth main through opening 50, and between the third main through opening 30 and the fifth main through opening 60.

[0080] Fig. 8 presents a seventh embodiment of the building block, differing from the sixth embodiment in that the second main through opening 20, third main through opening 30, and fifth main through opening 60 are circular. Instead of the first main through opening 10 and the fourth main through opening 50, it includes a first elongated main through opening 10A on the first side wall 11, with an obround shape with semicircles at the opposite sides coinciding with the fourth central axis X1 and the fifth central axis Z1, respectively.

[0081] Fig. 9 presents an eighth embodiment of the building block, differing from the sixth embodiment in that all main through openings 10, 20, 30, 50, 60 are circular.

[0082] Fig. 10 presents a ninth embodiment of the building block, which is a rectangular cuboid comprising a second main through opening 20 in the shape of a square, a first main through opening 10A in the shape of a rectangle, and a third main through opening 30A in the shape of a rectangle. The width w1 of the first and third main through openings 10A, 30A is one-third of the width A of the building block, while the length l1 of the first and third main through openings 10A, 30A is two-thirds of the width A. The central axes X, Y, Z of the main through openings 10A, 20, 30A coincide with the central axes of the building block, respectively.

[0083] Figs. 11A presents a connecting element in the form of a plastic first connector type. The first connector type 140A has a length equal to 40 mm and comprises two through holes 141 with axes distanced from each other by 1 / 3A (20 mm).

[0084] Fig. 11B presents the connecting element in the form of a plastic second connector type. The second connector type 140B has a length equal to A, which may be equal to 60 mm, and comprises two through holes 141 with axes distanced from each other by 2 / 3A (40 mm).

[0085] Fig. 11C presents the connecting element in the form of a plastic third connector type. The third connector type 140C has a length equal to A, which may be equal to 60 mm and comprises one longitudinal through hole 141Chaving a length equal to 50 mm. Moreover the third connector type 140C comprises two through holes 140 having the axes perpendicular to the longitudinal opening 140C. The axes of the through openings 141 are distanced from each other by 40 mm.

[0086] Fig. 11D presents the connecting element in the form of a plastic fourth connector type. The fourth connector type 140D has the form of a hollow rectangular cuboid. It comprises two through holes 141 whose axes are distanced from each other by 1 / 3A (20 mm) and comprising four bulges 142 (two pairs of bulges arranged in the opposite sides of the connector) with the axes perpendicular to the axes of the through holes 142 respectively. The fourth connector type 140D comprises a circumferential rim 143 located in the middle of the length of the connector. The rim 143 corresponds to the circumferential chamfer 73 of the square main through openings 10, 20, 30, 50, 60 of the building blocks.

[0087] Figs. 12A-12B present an exemplary structure comprising building blocks of the first embodiment connected by means of connecting elements 140 in the form of the beams 140, which may have circular cross sections (shafts 140E) or square cross sections (140F), fixed to the building blocks by second screws 120. Some building blocks are connected side by side by first screws 110. A single beam 140E, 140F may accommodate (connect) more than two building blocks.

[0088] Figs. 13A-13B present two building blocks connected by a shaft 140E, allowing rotation relative to each other.

[0089] Figs. 14A-14B present two building blocks 1A, 1B connected by the first connector type 140A and first screws 110, with the first screw 110 being longer than the width A of the building block, allowing direct connection of another building block without additional connectors.

[0090] Fig. 15A presents two building blocks 1A, 1B connected by the second connector type 140B and first screws 110, allowing them to be pivoted relative to each other.

[0091] Fig. 16 presents building blocks connected by the third connector type 140C.

[0092] Figs. 17A-17B present a wooden beam connecting element with a square cross section. The wooden beam 140F has a through hole 141 offset from the main longitudinal axis of symmetry of the wooden beam 140F by a distance x equal to 2 mm.

[0093] Figs. 18A-18C present a cover plate for square main through openings. The cover plate 150 has four mounting elements 151 on its inner side. Fig. 18D presents a building block with square main through openings with the cover plate 150. After attaching the cover plate 150 to the side of the building block, the mounting elements 151 are located in the corners of the main through opening.

[0094] Figs. 19A-19B present the cover plate 150 for circular main through openings, with the mounting element 151 shaped like a cylinder with an external rim to block the cover plate to the building block.

[0095] Figs. 20-25 present example structures made from the building blocks 1, such as a chair (Fig. 20), a rack (Fig. 21), a desk (Fig. 22), a table (Fig. 23), a vehicle (Fig. 24), or a car (Fig. 25).

Examples

second embodiment

[0071]Fig. 3 presents details of the main through opening of the first and the building block. The main through openings 10, 20, 30 have longitudinal indentations 71 located at their inner corners. The longitudinal indentations 71 are rounded.

[0072]Fig. 4A presents a third embodiment of the building block. The cubic building block of the third embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are circular.

[0073]Fig. 4B presents a fourth embodiment of the building block. The cubic building block of the fourth embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are polygonal.

[0074]Fig. 5A presents a second screw with a pointed end. The second screw has a length equal to 0.4A, wherein A is the width of the cubic building block and may be equal to 60 mm.

[0075]Fig. 5B presents a first screw having a flat end. The first screw has a length equal to 0.9A.

[0076]Fig. 5C presents a third screw having a divided end....

ninth embodiment

[0082]Fig. 10 presents the building block, which is a rectangular cuboid comprising a second main through opening 20 in the shape of a square, a first main through opening 10A in the shape of a rectangle, and a third main through opening 30A in the shape of a rectangle. The width w1 of the first and third main through openings 10A, 30A is one-third of the width A of the building block, while the length l1 of the first and third main through openings 10A, 30A is two-thirds of the width A. The central axes X, Y, Z of the main through openings 10A, 20, 30A coincide with the central axes of the building block, respectively.

[0083]Figs. 11A presents a connecting element in the form of a plastic first connector type. The first connector type 140A has a length equal to 40 mm and comprises two through holes 141 with axes distanced from each other by 1 / 3A (20 mm).

[0084]Fig. 11B presents the connecting element in the form of a plastic second connector type. The second connector type 140B has a...

first embodiment

[0087]Figs. 12A-12B present an exemplary structure comprising building blocks of the first embodiment connected by means of connecting elements 140 in the form of the beams 140, which may have circular cross sections (shafts 140E) or square cross sections (140F), fixed to the building blocks by second screws 120. Some building blocks are connected side by side by first screws 110. A single beam 140E, 140F may accommodate (connect) more than two building blocks.

[0088]Figs. 13A-13B present two building blocks connected by a shaft 140E, allowing rotation relative to each other.

[0089]Figs. 14A-14B present two building blocks 1A, 1B connected by the first connector type 140A and first screws 110, with the first screw 110 being longer than the width A of the building block, allowing direct connection of another building block without additional connectors.

[0090]Fig. 15A presents two building blocks 1A, 1B connected by the second connector type 140B and first screws 110, allowing them to b...

TECHNICAL FIELD

[0001] The present invention relates to a toy building block and to a toy construction system.BACKGROUND

[0002] Toy construction sets have long been popular among children and parents, promoting creativity, spatial reasoning, and fine motor skills. Traditional building blocks, typically made of wood or plastic, are limited in their connectivity and versatility, often only allowing for stacking or simple interlocking. These conventional blocks frequently suffer from several notable drawbacks, which hinder their utility and appeal.

[0003] One common issue with traditional building blocks is their limited interconnectivity. Many sets feature blocks that can only be connected in a single orientation, such as stacking vertically. This restriction severely limits the variety and complexity of structures that can be built. For example, popular interlocking bricks, such as those described in U.S. Pat. No. 3,005,282, connect primarily through male and female connectors on their upper and lower surfaces, constraining constructions to a single dimension and reducing the potential for creative, multi-directional designs.

[0004] Another limitation of traditional blocks is the visibility and structural role of the connecting mechanisms. In many sets, the connectors are not only visible but also integral to the structure stability. This often results in less aesthetically pleasing models, as the connectors detract from the overall appearance. Additionally, the fixed nature of these connectors can make assembly and disassembly cumbersome, reducing the enjoyment for users.

[0005] Some modern toy construction sets, such as those using rod and connector systems (as described in U.S. Pat. No. 5,238,438), allow for more diverse three-dimensional structures. However, these sets typically result in skeletal designs that lack the solidity and realism of traditional blocks. Furthermore, these designs often do not resemble everyday objects, limiting their educational value in demonstrating construction aspects.

[0006] Magnetically connected blocks and slotted card systems offer alternative methods of construction but come with their own sets of challenges. Magnetic connections can be weak, making it difficult to build stable, larger structures. Slotted card systems, while innovative, are often limited by the shape and size of the components, restricting the variety of possible constructions.SUMMARY OF THE INVENTION

[0007] There is a need to provide a toy building block with improved versatility and interconnectivity, enabling the construction of more complex and varied structures.

[0008] In one aspect, the invention relates to a cuboidal toy building block comprising six side walls arranged in three pairs of opposing side walls. The building block has three main through openings, each having a central axis perpendicular to one pair of opposing side walls. The central axes of these main through openings intersect at a common intersection point. Additionally, each side wall includes at least four primary threaded through openings arranged symmetrically around each main through opening, positioned between the main through opening and the edges of the side wall.

[0009] The arrangement of the main through openings along three perpendicular axes intersecting at a common point allows for multi-directional connectivity of building blocks. This enables the construction of complex and varied structures that are not limited to a single dimension.

[0010] The symmetrical arrangement of at least four primary threaded through openings around each main through opening ensures uniform distribution of connection points. This design provides multiple secure attachment points for screws or other fasteners, achieving the structural integrity and stability of assembled constructions. The symmetry also allows for consistent and predictable assembly, reducing the likelihood of misalignment between the building blocks and increasing ease of secure connection between the building blocks.

[0011] Depending on the size of the block or the specific design requirements, a greater number of primary threaded openings can be included, such as five, six, seven, eight, nine, ten, or more primary threaded through openings for larger blocks.

[0012] The threaded through openings are designed to be compatible with a range of screws and other fasteners. This compatibility allows for diverse construction possibilities, including both rigid and pivotable connections. The ability to use different types of connectors further extends the creative potential and functional applications of the building blocks.

[0013] The design of the building block, with its intersecting main through openings and symmetrically arranged threaded through openings, maintains a clean and aesthetically pleasing appearance. This design at least partially conceals the connecting mechanisms within the structure, resulting in more visually appealing models.

[0014] The intersecting main through openings and the symmetrical arrangement of threaded through openings contribute to the overall structural integrity and stability of the assembled constructions. This design ensures that the blocks can support more substantial and complex structures without compromising stability.

[0015] The building block is designed to be manufactured using 3D printing technologies, which allows for precise and consistent production of complex shapes and features. This method of production ensures high accuracy and quality, enabling the creation of durable and reliable building blocks that can withstand repeated use and assembly.

[0016] The building block may comprise at least four secondary threaded through openings in each side wall, arranged symmetrically around each main through opening between the primary threaded through openings. This provides additional connection points, further enhancing the structural integrity and stability of the assembled constructions. This increased number of connection points allows for more intricate and robust designs, making the building blocks suitable for constructing larger and more complex structures. The additional threaded through openings also offer greater flexibility in assembly, enabling users to create more varied and customized designs.

[0017] Depending on the size of the block or the specific design requirements, a greater number of secondary threaded openings can be included, such as five, six, seven, eight, nine, ten, or more threaded through openings for larger blocks.

[0018] The threaded through openings comprise at least a fragment of a single thread turn. In other words, the threaded through openings comprise at least a fragment of a ridge in the form of a helix.

[0019] The width of the main through openings can be equal to one-third of the width of the building block. That ensures a balanced and proportional design, which facilitates the alignment and connection of multiple blocks. The consistent ratio between the width of the main through openings and the width of the building block simplifies the design process and enhances the ease of assembly.

[0020] The building block may comprise a protrusion located on the inner wall of each main through opening. It compensates for dimensional inaccuracies of connecting elements, such as plastic or wooden beams and shafts, arising during the production process. The protrusion ensures a tight fit connection between the building block and the connecting elements, enhancing the stability and durability of the assembled structures. This is particularly useful when using materials that may expand or contract due to environmental factors, such as humidity or temperature changes.

[0021] The protrusion may have the form of an extra layer of material deposited on the inner side of the main through openings. The extra layer may be formed as single, double, or triple print layers. The protrusion may have the shape of an arc. The radius of the arc may be equal to the width of the building block side wall. For example, the protrusion, in the shape of an arc, can compensate for inaccuracies of 1 / 40 of the width in the diameter of the shaft or the width of the beam (for a width of 60 mm, this is 1.4 mm).

[0022] The protrusion may also have the form of elongated bulges arranged parallel to the central axis of the main through opening.

[0023] The protrusion may also be defined as a pressure element, providing a tight fit connection between the building block and the connecting elements.

[0024] The main through openings may have a square shape. It provides a uniform and predictable connection interface, which simplifies the design and assembly process. The square shape allows for precise alignment of the connecting elements, ensuring a secure and stable connection without a risk of rotation of the connecting element or the building block along the longitudinal axis of the connecting element with a square cross section. Nevertheless, the main through openings may also accommodate other connecting elements having other cross sections, such as rounded connecting elements (such as shafts), if there is a need for rotation of the building block around the connecting element.

[0025] The building block may comprise longitudinal indentations located at the inner corners of the main through openings. It protects against material shrinkage during the printing process, which can lead to rounding of the 90-degree angles of the square openings. The indentations ensure that the connecting elements, such as beams with square cross sections, can be easily inserted and securely held in place. The longitudinal indentations located at the inner corners of the square main through openings may also be defined as corner grooves. The longitudinal indentations may have a diameter of 1 mm (regardless of the adopted dimensions of the building block.

[0026] The main through openings can be circular. It allows for rotational movement of the connecting elements of any cross section, enabling the construction of dynamic and movable structures. The circular openings can accommodate shafts and other cylindrical connectors, providing greater flexibility in design and assembly. This is particularly useful for creating structures with rotating or pivoting components, such as wheels or hinges.

[0027] The main through openings may have a polygonal shape. Such a feature offers a unique and versatile connection interface, which can accommodate a variety of connecting elements with matching polygonal cross sections. The polygonal shape provides multiple flat surfaces for different, but specified angular positions of connecting elements or building blocks.

[0028] At least one edge of the building block can be rounded. It enhances the safety and usability of the building blocks, particularly for younger children. The rounded edges reduce the risk of injury from sharp corners, making the blocks safer to handle and play with.

[0029] In a particular embodiment, the building block may have the form of a cube, with the central axes of the main through openings coinciding with the symmetry axes of the building block. This provides a highly symmetrical and balanced design, which simplifies the alignment and connection of multiple blocks. The cubic form ensures that the blocks can be easily stacked and connected in any orientation, enhancing the versatility and ease of assembly.

[0030] The primary threaded through openings can be arranged on the axes of symmetry of the side walls, with each opening positioned on the opposite side of the respective main through opening. This ensures a uniform distribution of connection points, which enhances the structural integrity and stability of the assembled constructions. The symmetrical arrangement reduces the likelihood of misalignment and ensures that the blocks can be securely connected in any orientation.

[0031] In a particular embodiment, the building block may have an elongated form, such as it may have a length two times longer than its width. This design provides a larger and more versatile building block, which can be used to create more extensive and complex structures. The elongated form allows for the construction of longer spans and larger surfaces, making the blocks suitable for building furniture and other functional items.

[0032] The main openings may have a longitudinal shape. The longitudinal main openings provide additional versatility in the location of the connecting elements, further enhancing the versatility and structural integrity of the assembled constructions.

[0033] The elongated building block may further comprise a fourth main opening with a central axis perpendicular to a pair of opposing side walls, intersecting the second central axis and parallel to the first central axis. This provides an additional connection point, which enhances the versatility and complexity of the assembled structures. The fourth main opening allows for multi-directional connectivity, enabling the construction of more intricate and robust designs. This feature also increases the flexibility of the building blocks, allowing users to create more customized and varied structures.

[0034] The elongated building block may further comprise a fifth main opening with a central axis perpendicular to a pair of opposing side walls, parallel to the third central axis, and intersecting the fourth and second central axes at a second common intersection point. This provides an additional connection point, enhancing the versatility and complexity of the assembled structures. The fifth main opening allows for even more multi-directional connectivity, enabling the construction of highly intricate and robust designs. This feature also increases the flexibility of the building blocks, allowing users to create more customized and varied structures.

[0035] The building block may have two rows of threaded through openings located between the first and fourth main through openings. This provides additional connection points, enhancing the structural integrity and stability of the assembled constructions. The double rows of threaded through openings allow for more secure and robust connections, making the building blocks suitable for constructing larger and more complex structures. This feature also increases the flexibility of the building blocks, allowing users to create more varied and customized designs.

[0036] The building block may have two rows of threaded through openings located between the third and fifth main through openings. This provides additional connection points, enhancing the structural integrity and stability of the assembled constructions. The double rows of threaded through openings allow for more secure and robust connections, making the building blocks suitable for constructing larger and more complex structures. This feature also increases the flexibility of the building blocks, allowing users to create more varied and customized designs.

[0037] The building block can be made using a 3D printing process. This allows for precise and consistent production of complex shapes and features, ensuring high accuracy and quality. The 3D printing process enables the creation of durable and reliable building blocks that can withstand repeated use and assembly. This manufacturing method also allows for rapid prototyping and customization, making it possible to produce building blocks with unique and intricate designs. Additionally, 3D printing reduces material waste and production costs, making the building blocks more environmentally friendly and cost-effective.

[0038] In another aspect, the present invention relates to a toy construction system comprising at least two building blocks as described herein and at least one first screw having a thread compatible with the threaded through openings for connecting the building blocks. The first screw is useful for assembly and disassembly of the building blocks. This allows users to quickly and securely connect multiple blocks, facilitating the construction of more complex structures. The compatibility of the screw thread with the threaded through openings ensures a tight fit, reducing the risk of structural instability. This advantage is particularly beneficial for creating robust and durable models that can withstand repeated use and manipulation.

[0039] The construction system may further comprise at least one second screw with a pointed end and at least one wooden or plastic connecting element for connecting building blocks by inserting the connecting element into the main through opening and securing it with the second screw. The use of the second screw with a pointed end and wooden or plastic connecting elements introduces the ability to create semi-permanent connections that can be easily adjusted or modified. This feature is advantageous for prototyping and iterative design processes, allowing users to experiment with different configurations before finalizing their structures. The pointed end of the screw ensures a secure grip on the connecting element, enhancing the overall stability of the construction.

[0040] The second screw may have a pointed conical end. When the building blocks are connected by means of connecting elements in the form of wooden beams or shafts, the pointed conical end penetrates the material of the beam or shaft, maintaining it in a fixed position. This functionality is especially useful when prototyping new structures. When the structure has its final design, it may be disassembled. The second screw with a pointed, hard end, when tightened, leaves a visible mark on the wooden beam or shaft. Thereafter, in the beams or shafts, at the locations of the marks, through holes may be drilled. The structure may be assembled again, and instead of short pointed-ended second screws, the longer first screws with flat ends are used, which go through the beam, securing it in the desired position and providing increased strength and stiffness to the structure. Preferably, the through holes are offset from the main axis of symmetry of the beam by a distance x to provide tension to the screw. The material of the screw is slightly flexible and bends in the region of the opening, providing additional tightness of the connection and stiffness to the structure. The distance x may be equal to 1 / 30A (for example, about 2 mm). Due to this, various functional structures made of the building blocks maintain the required level of stiffness to fulfill their tasks. Moreover, due to the screw flexibility, the structure can absorb momentary abnormal loads (e.g., bending of the leg caused by moving the table or rocking on a chair).

[0041] The second screws with the pointed end may also be used in connection with shafts having a circumferential groove. The pointed end of the screw enters the circumferential groove, preventing the shaft from falling out of the building block while maintaining its freedom to rotate.

[0042] The construction system may further comprise at least one connecting element with at least one through hole for connecting building blocks by inserting the connecting element into the main through opening and securing it with the first screw. This allows forming strong structures. On the other hand, when using rounded connecting elements, this allows for the creation of pivotable connections between building blocks. This feature enables the construction of dynamic and movable structures, such as rotating joints or hinges, which are not possible with traditional building blocks. The ability to create pivotable connections adds a new dimension of interactivity and functionality to the toy construction set, enhancing its educational value by demonstrating mechanical principles.

[0043] Alternatively, third screws may be used, which have a split end. The split end may be formed by making a notch or slit at the initially flat end of the screw. Thereafter, the two halves of the end may be slightly bent outwardly, particularly under increased temperature. Such treatment results in the split end tending to maintain its outwardly bent position and prevents the self-unscrewing of the third screw.

[0044] Depending on the material of the third screw, a different angle of outward bending may be required. The more flexible the material, the wider the notch should be to generate greater internal stresses that oppose the forces created during usage of the structure (e.g., due to vibration). When screwing the third screw with a split or expanded end into a threaded through opening, the notch temporarily closes, and when it reaches the open chamber of the building block, it expands like an expansion pin, returning to the default expanded shape induced during thermal treatment. The open chamber may be another threaded through opening located on the other side of the building block.

[0045] Preferably, the screws have a diameter of 1 / 3A, a thread pitch of 1 / 2A, and a head diameter of 0.65A. Such dimensions allow them to self-screw under the influence of gravity. The screws only require final tightening at the head height (the threaded through opening in the building block for the screw head has a larger diameter by 0.2 mm, which considering the accuracy of 3D printing from plastics generates sufficient fit and screw holding).

[0046] The second screw may have a length equal to 0.4A. The first and third screws may have lengths equal to 0.9A and 1.55A or longer.

[0047] The longer screws may be used to directly connect two building blocks together, without any connecting elements.

[0048] The connecting element may have a longitudinal through hole. This provides the capability for longitudinal and pivotable movement between connected building blocks. This allows for the creation of telescoping structures or adjustable-length components, adding versatility to the construction set. The ability to adjust the length of connections dynamically enhances the user's ability to create custom-sized structures tailored to specific needs or preferences.

[0049] The connecting element may have two through holes located at its ends. This facilitates the creation of stable and secure connections between multiple building blocks. This feature allows for the construction of more complex and interconnected structures, such as frameworks or scaffolding, by providing multiple attachment points. The dual through holes ensure that the connected blocks remain aligned and stable, even under load or stress. This enhanced stability and structural integrity are particularly beneficial for building larger and more intricate models.

[0050] In a particular embodiment, the connecting element is a wooden beam with two through holes located at its ends. Using wooden beams with through holes as connecting elements introduces a natural and sustainable material option for the construction set. Wooden beams provide a unique aesthetic and tactile experience, appealing to users who prefer natural materials over plastic. The through holes in the wooden beams ensure secure connections with the building blocks, maintaining the structural integrity of the assembled models. This feature also allows for the integration of traditional woodworking techniques with modern toy construction, offering a blend of old and new that is not available in conventional building block sets. Wooden beams can be also easily replaced by users themselves in case they are damaged. Furthermore, users may easily produce wooden connecting elements on their own in order to adjust the length of the connecting element to needs for a particular construction.

[0051] In the case of connecting elements in the form of beams, the diameter of the beam (shaft) with a circular cross section, as well as the transverse dimensions of the square beams, is preferably lower than 1 / 3A. Under ideal laboratory conditions, a perfect tight fit can be achieved for components manufactured from hard materials (e.g., steel); however, in the case of wooden or plastic connecting elements, dimensional accuracy can be as low as-2%A. Gaps in the construction caused by the use of connecting elements with lower dimensions than the dimensions of the main through openings are compensated by protrusions.

[0052] The connecting elements may be of any length equal to or greater than 2 / 3A, as this is the minimum distance that allows for two adjacent blocks to be connected, regardless of whether they have pre-drilled through holes (for first or third screws) or not (for use with second screws).

[0053] Preferably, the cross-sectional shape of the connecting element matches the shape of the main through openings.

[0054] The connecting elements in the form of beams and shafts are responsible for carrying the greatest loads in utility structures such as chairs or tables. In such structures for demanding applications (furniture), the entire weight of the person or structure rests on the beams, while the building blocks are only responsible for maintaining them properly held in place. The applied force (e.g., human weight) is transferred along the beam directly to the floor. The connecting elements in the form of beams and shafts allow for connecting multiple building blocks.

[0055] The connecting elements may also have the form of 3D printed plastic connectors with rounded ends. Such connecting elements allow for pivotable connection between the building blocks.

[0056] A first connector type is used for connecting two building blocks such that their relative movement is restricted.

[0057] A second connector type is used for connecting two building blocks such that their relative pivotal movement is possible.

[0058] A third connector type is used for connecting two building blocks such that their relative pivotal and longitudinal movement is possible. The third connector type has a longitudinal through hole, which provides longitudinal movement. The third connector type may also comprise two circular through holes with the axes perpendicular to the longitudinal through hole, located at its ends. This provides a double functionality of the connector - first pivotal functionality, same as for second type connectors, and second pivotal and longitudinal displacement functionality.

[0059] A fourth connector type features two through holes for securing the connector with screws and four elastic bulges for locking the connector into the building block without screws. The axes of the through holes are perpendicular to the axes of the bulges, respectively. The fourth connector type is suitable for connecting building blocks with main through openings in the shape of a square. Utilizing the fourth connector type for connecting the building blocks via the bulges allows for rapid connection and disconnection of blocks, which is advantageous when prototyping new structures.

[0060] The building block may comprise cover plates for covering the main through openings and the threaded through openings. The cover plate has mounting elements corresponding to the shape of the main through openings, allowing the cover plate to be snap-fitted into the main through opening. The cover plates serve an aesthetic function, enabling the main through openings of the building blocks to be closed after the structure is completed. Additionally, the cover plates may have printed elements such as texts or graphics, or may function as a smooth surface for a sticker.

[0061] The toy building block and other elements of the toy building set can be manufactured by 3D printing, using technologies such as FDM (Fused Deposition Modelling) and SLS (Selective Laser Sintering), depending on the desired strength of the elements and their applications. Each of these technologies uses specific materials that have unique properties and applications (for screws, needed flexibility, and for cubes, stiffness).

[0062] FDM is the most common 3D printing technology, which involves melting and extruding a thermoplastic filament through a nozzle that applies the material layer by layer. The main materials used in FDM printing technology are: PLA (Polylactide): A biodegradable plastic that is easy to print and has a low melting point (about 180-220°C). It is relatively stiff and brittle, making it ideal for prototypes and decorative models. ABS (Acrylonitrile-Butadiene-Styrene): A tough plastic that is resistant to impact and high temperatures (approximately 220-250°C). It is more durable than PLA but more challenging to print due to its tendency to shrink and warp. PETG (Polyethylene Terephthalate Glycol): Combines the properties of PLA and ABS, being strong, flexible, resistant to chemicals, and easier to print than ABS. It is used at temperatures of about 220-250°C.

[0063] Another group of materials includes fiber-reinforced materials such as: PACF (Carbon Fiber Reinforced Polyamide): Offers high mechanical strength, stiffness, temperature, and abrasion resistance. It is ideal for automotive components, machine parts, and equipment housings. PAGF (Glass Fiber Reinforced Polyamide): Provides increased strength and stiffness with good impact resistance. It is used for structural components. PLA CF (Carbon Fiber Reinforced Polylactide): Offers better rigidity and strength than standard PLA while maintaining ease of printing. ABS CF (Carbon Fiber Reinforced Acrylonitrile-Butadiene-Styrene): Provides higher mechanical strength, stiffness, impact, and temperature resistance. PC CF (Carbon Fiber Reinforced Polycarbonate): Offers high strength and stiffness, along with temperature and impact resistance.

[0064] The SLS (Selective Laser Sintering) process uses a laser to sinter polymer, metal, or ceramic powders to form solid layers. Although the SLS printing process is slow and expensive, it can be very useful for creating load-bearing structures such as tents and store shelving. With these materials, it is possible to create more durable, strong, and precise components. The main materials used in the SLS printing technology are: PA (Polyamides, e.g., PA12, PA11): Known for high mechanical strength, impact, and chemical resistance. TPU (Thermoplastic Polyurethane): A flexible powder used for manufacturing parts requiring flexibility and abrasion resistance. Composites: Powders reinforced with glass or carbon fibers, which increase the strength and stiffness of printouts. Metals: Such as stainless steel, aluminum, and titanium, used to print metal parts in advanced engineering applications.

[0065] The elements of the toy building set can also be produced by injection molding and traditional methods such as machining. However, due to the complex shapes, these methods are very time-consuming and problematic, though feasible.

[0066] The presented toy construction set may be used for constructing various structures such as chairs, tables, racks, as well as toy structures such as houses, boxes, or vehicles.BRIEF DESCRIPTION OF DRAWINGS

[0067] The present invention is shown by means of preferable embodiments in a drawing, wherein: Fig. 1A presents a first embodiment of the building block in an isometric view; Fig. 1B presents the first embodiment of the building block in a front view; Fig. 2A presents a second embodiment of the building block with a protrusion in a front view; Fig. 2B presents a fragment of the cubic building block of Fig. 2A in a cross-sectional view; Fig. 2C presents detail D from Fig. 2B; Fig. 3 presents details of the main through opening of the first and the second embodiment of the building block; Fig. 4A presents a third embodiment of the building block, in an isometric view; Fig. 4B presents a fourth embodiment of the building block, in an isometric view; Fig. 5A presents a second screw, in a side view; Fig. 5B presents a first screw, in a side view; Fig. 5C presents a third screw with a divided end, in a side view; Fig. 6 presents a fifth embodiment of the building block, in an isometric view; Fig. 7A presents a sixth embodiment of the building block, in an isometric view; Fig. 7B presents the sixth embodiment of the building block, in a side view; Fig. 7C presents the sixth embodiment of the building block, in a front view; Fig. 8 presents a seventh embodiment of the building block, in an isometric view; Fig. 9 presents an eighth embodiment of the building block, in an isometric view; Fig. 10 presents a ninth embodiment of the building block, in an isometric view; Fig. 11A presents a connecting element in the form of a plastic first connector type; Fig. 11B presents the connecting element in the form of a plastic second connector type; Fig. 11D presents the connecting element in the form of a plastic fourth connector type; Fig. 12A presents an exemplary structure with connecting elements in the form of beams, in a side view; Fig. 12B presents an exemplary structure with connecting elements in the form of beams, in an isometric view; Fig. 13A presents two building blocks with a connecting element in the form of a shaft, in a side view; Fig. 13B presents two building blocks with a connecting element in the form of a shaft, in a cross-sectional view; Fig. 14A presents two building blocks connected by the first connector type in a top view; Fig. 14B presents two building blocks connected by the first connector type in a cross-sectional view; Fig. 15A presents two building blocks connected by the second connector type in a cross-sectional view; Fig. 15B presents two building blocks connected by the second connector type in a front view; Fig. 16 presents building blocks connected by the third connector type in a front view; Fig. 17A presents a wooden beam connecting element in a side view; Fig. 17B presents a cross section B-B from Fig. 17A; Fig. 18A presents a cover plate for square main through openings, in a side view; Fig. 18B presents the cover plate from Fig. 18A, in a front view; Fig. 18C presents the cover plate from Fig. 18A, in a back view; Fig. 18D presents a building block with square main through openings with the cover plate; Fig. 19A presents a cover plate for circular main through openings in a back view; Fig. 19B presents a cover plate for circular main through openings in a side view; Fig. 20 presents an exemplary structure in the form of a chair; Fig. 21 presents an exemplary structure in the form of a rack; Fig. 22 presents an exemplary structure in the form of a desk; Fig. 23 presents an exemplary structure in the form of a table; Fig. 24 presents an exemplary structure in the form of a vehicle; Fig. 25 presents an exemplary structure in the form of a car. DETAILED DESCRIPTION OF EMBODIMENTS

[0068] Figs. 1A-1B present a first embodiment of the toy building block. In the first embodiment, the building block has the form of a cube with six side walls 11, 12, 21, 22, 31, 32 arranged in three pairs 11-12, 21-22, 31-32 of opposing side walls. The building block comprises three main through openings 10, 20, 30 in the shape of a square. Central axes X, Y, Z of the main through openings 10, 20, 30 coincide with the symmetry axes of the building block respectively, which intersect at a first common intersection point P1. Each side wall 11, 12, 21, 22, 31, 32 comprises eight threaded through openings 41, 42 arranged uniformly around each main through opening 10, 20, 30. Eleven of the twelve edges of the building block are rounded. The width d of the main through openings 10, 20, 30 is equal to 1 / 3 of the width A of the building block. The width A of the building block is equal to 60 mm. The main through openings 10, 20, 30 comprise circumferential chamfers 73.

[0069] The first two primary threaded through openings 41 are arranged on the first axis of symmetry S1 of the side wall, each on the opposite side of the respective main through opening 10, 20, 30, and the second two primary threaded through openings 41 are arranged on the second axis of symmetry S2 of the side wall, each on the opposite side of the respective main through opening 10, 20, 30, wherein the axes of symmetry S1, S2 of the side wall are perpendicular to the edges of the respective side wall. The second threaded through openings 42 are arranged between the first threaded through openings 41.

[0070] Figs. 2A-2C present a second embodiment of the building block. The building block in the second embodiment differs from the first embodiment in that it additionally comprises a protrusion 70, located on every inner side wall of each main through opening 10, 20, 30. The protrusion 70 has a shape of an arc and is formed of two layers of 3D print material.

[0071] Fig. 3 presents details of the main through opening of the first and the second embodiment of the building block. The main through openings 10, 20, 30 have longitudinal indentations 71 located at their inner corners. The longitudinal indentations 71 are rounded.

[0072] Fig. 4A presents a third embodiment of the building block. The cubic building block of the third embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are circular.

[0073] Fig. 4B presents a fourth embodiment of the building block. The cubic building block of the fourth embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are polygonal.

[0074] Fig. 5A presents a second screw with a pointed end. The second screw has a length equal to 0.4A, wherein A is the width of the cubic building block and may be equal to 60 mm.

[0075] Fig. 5B presents a first screw having a flat end. The first screw has a length equal to 0.9A.

[0076] Fig. 5C presents a third screw having a divided end. The divided end has two arms 131 which are distanced from each other by a notch. The length of the arms 131 is equal to 0.2A.

[0077] Fig. 6 presents a fifth embodiment of the building block. The building block of the fifth embodiment is in the form of a rectangular cuboid and comprises a first main through opening 10 with a first central axis X, a second main through opening 20 with a second central axis Y, and a third main through opening 30 with a third central axis Z. The central axes X, Y, and Z intersect each other at a first common intersection point P1. The central axis X is equidistant from the fifth side wall 31 and the third side wall 21, the distance being equal to half the width A of the building block. Similarly, the central axis Y is equidistant from the first side wall 11 and the fifth side wall 31, and the central axis Z is equidistant from the third side wall 21 and the first side wall 11, each distance equal to by half the width A of the building block.

[0078] The building block further comprises a fourth main through opening 50 with a fourth central axis X1 perpendicular to a first pair of opposing side walls 11, 12, intersecting the second central axis Y and parallel to the first central axis X. Additionally, it comprises a fifth main through opening 60 with a fifth central axis Z1 perpendicular to a third pair of opposing side walls 31, 32, parallel to the third central axis Z, and intersecting the fourth central axis X1 and the second central axis Y at a second common intersection point P2. The fifth central axis Z1 is equidistant from the first side wall 11 and the fourth side wall 22, and the fourth central axis X1 is equidistant from the fifth side wall 31 and the fourth side wall 22, each by half the width A of the building block. The main through openings 10, 20, 30, 50, 60 are square-shaped with a width equal to one-third of the width A. The third 21 and fourth side walls 22 each have eight threaded through openings 41, 42, while the first 11, second 12, fifth 31, and sixth 32 side walls each have thirteen threaded through openings 41, 42, with rows of three threaded through openings located between the first main through opening 10 and the fourth main through opening 50, and between the third main through opening 30 and the fifth main through opening 60. Eleven of the twelve edges of the building block are rounded.

[0079] Figs. 7A-7C present a sixth embodiment of the building block, which is a rectangular cuboid with a length L twice its width A. This embodiment differs from the fifth embodiment in that the first 11, second 12, fifth 31, and sixth 32 side walls have sixteen threaded through openings 41, 42, with two rows of three threaded through openings 41, 42 located between the first main through opening 10 and the fourth main through opening 50, and between the third main through opening 30 and the fifth main through opening 60.

[0080] Fig. 8 presents a seventh embodiment of the building block, differing from the sixth embodiment in that the second main through opening 20, third main through opening 30, and fifth main through opening 60 are circular. Instead of the first main through opening 10 and the fourth main through opening 50, it includes a first elongated main through opening 10A on the first side wall 11, with an obround shape with semicircles at the opposite sides coinciding with the fourth central axis X1 and the fifth central axis Z1, respectively.

[0081] Fig. 9 presents an eighth embodiment of the building block, differing from the sixth embodiment in that all main through openings 10, 20, 30, 50, 60 are circular.

[0082] Fig. 10 presents a ninth embodiment of the building block, which is a rectangular cuboid comprising a second main through opening 20 in the shape of a square, a first main through opening 10A in the shape of a rectangle, and a third main through opening 30A in the shape of a rectangle. The width w1 of the first and third main through openings 10A, 30A is one-third of the width A of the building block, while the length l1 of the first and third main through openings 10A, 30A is two-thirds of the width A. The central axes X, Y, Z of the main through openings 10A, 20, 30A coincide with the central axes of the building block, respectively.

[0083] Figs. 11A presents a connecting element in the form of a plastic first connector type. The first connector type 140A has a length equal to 40 mm and comprises two through holes 141 with axes distanced from each other by 1 / 3A (20 mm).

[0084] Fig. 11B presents the connecting element in the form of a plastic second connector type. The second connector type 140B has a length equal to A, which may be equal to 60 mm, and comprises two through holes 141 with axes distanced from each other by 2 / 3A (40 mm).

[0085] Fig. 11C presents the connecting element in the form of a plastic third connector type. The third connector type 140C has a length equal to A, which may be equal to 60 mm and comprises one longitudinal through hole 141Chaving a length equal to 50 mm. Moreover the third connector type 140C comprises two through holes 140 having the axes perpendicular to the longitudinal opening 140C. The axes of the through openings 141 are distanced from each other by 40 mm.

[0086] Fig. 11D presents the connecting element in the form of a plastic fourth connector type. The fourth connector type 140D has the form of a hollow rectangular cuboid. It comprises two through holes 141 whose axes are distanced from each other by 1 / 3A (20 mm) and comprising four bulges 142 (two pairs of bulges arranged in the opposite sides of the connector) with the axes perpendicular to the axes of the through holes 142 respectively. The fourth connector type 140D comprises a circumferential rim 143 located in the middle of the length of the connector. The rim 143 corresponds to the circumferential chamfer 73 of the square main through openings 10, 20, 30, 50, 60 of the building blocks.

[0087] Figs. 12A-12B present an exemplary structure comprising building blocks of the first embodiment connected by means of connecting elements 140 in the form of the beams 140, which may have circular cross sections (shafts 140E) or square cross sections (140F), fixed to the building blocks by second screws 120. Some building blocks are connected side by side by first screws 110. A single beam 140E, 140F may accommodate (connect) more than two building blocks.

[0088] Figs. 13A-13B present two building blocks connected by a shaft 140E, allowing rotation relative to each other.

[0089] Figs. 14A-14B present two building blocks 1A, 1B connected by the first connector type 140A and first screws 110, with the first screw 110 being longer than the width A of the building block, allowing direct connection of another building block without additional connectors.

[0090] Fig. 15A presents two building blocks 1A, 1B connected by the second connector type 140B and first screws 110, allowing them to be pivoted relative to each other.

[0091] Fig. 16 presents building blocks connected by the third connector type 140C.

[0092] Figs. 17A-17B present a wooden beam connecting element with a square cross section. The wooden beam 140F has a through hole 141 offset from the main longitudinal axis of symmetry of the wooden beam 140F by a distance x equal to 2 mm.

[0093] Figs. 18A-18C present a cover plate for square main through openings. The cover plate 150 has four mounting elements 151 on its inner side. Fig. 18D presents a building block with square main through openings with the cover plate 150. After attaching the cover plate 150 to the side of the building block, the mounting elements 151 are located in the corners of the main through opening.

[0094] Figs. 19A-19B present the cover plate 150 for circular main through openings, with the mounting element 151 shaped like a cylinder with an external rim to block the cover plate to the building block.

[0095] Figs. 20-25 present example structures made from the building blocks 1, such as a chair (Fig. 20), a rack (Fig. 21), a desk (Fig. 22), a table (Fig. 23), a vehicle (Fig. 24), or a car (Fig. 25).

Examples

second embodiment

[0071]Fig. 3 presents details of the main through opening of the first and the building block. The main through openings 10, 20, 30 have longitudinal indentations 71 located at their inner corners. The longitudinal indentations 71 are rounded.

[0072]Fig. 4A presents a third embodiment of the building block. The cubic building block of the third embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are circular.

[0073]Fig. 4B presents a fourth embodiment of the building block. The cubic building block of the fourth embodiment differs from the second embodiment in that the main through openings 10, 20, 30 are polygonal.

[0074]Fig. 5A presents a second screw with a pointed end. The second screw has a length equal to 0.4A, wherein A is the width of the cubic building block and may be equal to 60 mm.

[0075]Fig. 5B presents a first screw having a flat end. The first screw has a length equal to 0.9A.

[0076]Fig. 5C presents a third screw having a divided end....

ninth embodiment

[0082]Fig. 10 presents the building block, which is a rectangular cuboid comprising a second main through opening 20 in the shape of a square, a first main through opening 10A in the shape of a rectangle, and a third main through opening 30A in the shape of a rectangle. The width w1 of the first and third main through openings 10A, 30A is one-third of the width A of the building block, while the length l1 of the first and third main through openings 10A, 30A is two-thirds of the width A. The central axes X, Y, Z of the main through openings 10A, 20, 30A coincide with the central axes of the building block, respectively.

[0083]Figs. 11A presents a connecting element in the form of a plastic first connector type. The first connector type 140A has a length equal to 40 mm and comprises two through holes 141 with axes distanced from each other by 1 / 3A (20 mm).

[0084]Fig. 11B presents the connecting element in the form of a plastic second connector type. The second connector type 140B has a...

first embodiment

[0087]Figs. 12A-12B present an exemplary structure comprising building blocks of the first embodiment connected by means of connecting elements 140 in the form of the beams 140, which may have circular cross sections (shafts 140E) or square cross sections (140F), fixed to the building blocks by second screws 120. Some building blocks are connected side by side by first screws 110. A single beam 140E, 140F may accommodate (connect) more than two building blocks.

[0088]Figs. 13A-13B present two building blocks connected by a shaft 140E, allowing rotation relative to each other.

[0089]Figs. 14A-14B present two building blocks 1A, 1B connected by the first connector type 140A and first screws 110, with the first screw 110 being longer than the width A of the building block, allowing direct connection of another building block without additional connectors.

[0090]Fig. 15A presents two building blocks 1A, 1B connected by the second connector type 140B and first screws 110, allowing them to b...

Claims

1. A cuboidal toy building block comprising: - six side walls (11, 12, 21, 22, 31, 32) arranged in three pairs of opposing side walls (11, 12, 21, 22, 31, 32); - a first main through opening (10) having a first central axis (X) perpendicular to a first pair (11, 12) of opposing side walls; - a second main through opening (20) having a second central axis (Y) perpendicular to a second pair (21, 22) of opposing side walls; - a third main through opening (30) having a third central axis (Z) perpendicular to a third pair (31, 32) of opposing side walls; - wherein the central axes (X, Y, Z) intersect each other at a first common intersection point (P1); and - at least four primary threaded through openings (41) in each side wall, arranged symmetrically around each main through opening (10, 20, 30) between the main through opening (10, 20, 30) and each of the edges of the side wall.

2. The building block according to claim 1, comprising at least four secondary threaded through openings (42) in each side wall (11, 12, 21, 22, 31, 32), arranged symmetrically around each main through opening (10, 20, 30) between the primary threaded through openings (41).

3. The building block according to claim 1 or 2, wherein the width (d) of the main through opening (10, 20, 30) is equal to one third of the width (A) of the building block.

4. The building block according to any of the previous claims, comprising a protrusion (70) located on the inner wall of each main through opening (10, 20, 30).

5. The building block according to any of the previous claims, wherein the main through openings (10, 20, 30) have a shape of a square.

6. The building block according to claim 5, wherein the main through openings have longitudinal indentations (71) located at their inner corners.

7. The building block according to any of the previous claims, wherein the building block (1) has the form of a cube, wherein the central axes (X, Y, Z) of the main through openings (10, 20, 30) coincide with the symmetry axes of the building block (1) respectively.

8. The building block according to claim 7, wherein the first two of the primary threaded through openings (41) are arranged on the first axis of symmetry (S1) of the side wall, each on the opposite side of the respective main through opening (10, 20, 30); and the second two of the primary threaded through openings (41) are arranged on the second axis of symmetry (S2) of the side wall, each on the opposite side of the respective main through opening (10, 20, 30); wherein the axes of symmetry (S1, S2) of the side wall are perpendicular to the edges of the respective side wall.

9. The building block according to any of claims 1 to 6, wherein the building block has a length (L) that is twice its width (A).

10. The building block according to claim 9, comprising a fourth main through opening (50) having a fourth central axis (X1) perpendicular to a first pair (11, 12) of opposing side walls, intersecting the second central axis (Y) and parallel to the first central axis (X), wherein the central axes (X, X1, Y, Z) are located at a distance equal to one-quarter of the length (L) from at least three edges of the respective side wall.

11. The building block according to claim 10, wherein the building block comprises a fifth main through opening (60) having a fifth central axis (Z1) perpendicular to a third pair (31, 32) of opposing side walls, parallel to the third central axis (Z) and intersecting the fourth central axis (X1) and the second central axis (Y) at a second common intersection point (P2).

12. A toy construction system comprising: at least two building blocks according to any of claims 1 to 11; and at least one first screw (110), having a thread compatible with the thread of the threaded through openings (41, 42), for connecting the at least two building blocks (1) by screwing the first screw (110) into the threaded through opening (41, 42) of the first building block (1A) and the second building block (1B).

13. The construction system according to claim 12, comprising at least one second screw (120) with a pointed end (121) and at least one wooden or plastic connecting element (140) for connecting at least two building blocks (1) by inserting the connecting element (140) into the main through opening (10, 20, 30) and securing it with the second screw (120).

14. The construction system according to claim 12, comprising at least one connecting element (140) with at least one through hole (141) for connecting at least two building blocks (1) by inserting the connecting element (140) into the main through opening (10, 20, 30) and securing it with a first screw (110).

15. The construction system according to claim 14, wherein the connecting element (140) has a longitudinal through-hole (141C).

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