Connectable polygonal construction modules

Polygonal construction modules are capable of being connected together by their edges and by their faces to create many different three-dimensional shapes. Each module has a generally planar body with edge faces, a top face and a bottom. Each edge face has a plurality of outwardly projecting fingers designed to provide a snap-together lateral interlock between fingers of adjacent modules while permitting hinging or rotation between modules on an axis parallel to the side face. Projecting upwardly from each top face is at least one annular connector element for establishing a friction fit with a like connector element in face-to-face interlocking engagement. The connector element includes a series of projections arranged in a uniform circular array, each projection being segmental in shape with radial side walls. The space between each pair of projections is the same shape and size as each projection whereby to snugly receive and hold a projection of a like connector element solely by frictional contact between engaging projection side walls. The body portion directly beneath each connector element is thin relative to the height and width of each projection to thereby provide the array as a whole with substantially greater flexibility than the intrinsic flexibility of each projection. In this manner, dimensional inaccuracies of the projections are accommodated when engaged with a like connector element, thereby enhancing the firmness of frictional contact between engaging projection side walls.

BACKGROUND OF THE INVENTION 
This invention relates to building polyhedra building toys and, more 
particularly, to polygonal construction modules capable of being connected 
together by their edges and by their faces. 
Various types of construction toys and sets have been known and one example 
is shown in Zimmerman, U.S. Pat. No. 2,776,521 issued Jan. 8, 1957. The 
object of the Zimmerman design is to provide a construction toy in which 
the basic units are flat, simple geometric figures, such as squares or 
equilateral triangles which are adapted to be joined to each other to form 
three-dimensional figures. In particular, it relates to a construction toy 
in which the basic units are provided with identical edges adapted to mesh 
to form a hinge and allow a large number of configurations to be 
assembled, including many regular three-dimensional geometric shapes. 
Another form of construction set with modular elements is described in 
Quercetti, U.S. Pat. No. 3,442,044 issued May 6, 1969. This design 
utilizes a combination of facially projecting pins and corresponding 
recesses which allows connecting together of the modular components. 
Another prior design in which modular components are connected together by 
means of a series of pin-like prongs is described in Heubl, U.S. Pat. No. 
3,603,025 issued Sept. 7, 1971. 
It is an object of the present invention to provide polygonal construction 
modules capable of being fastened to one another both edge-to-edge, 
face-to-face and face-to-back. 
SUMMARY OF THE INVENTION 
One principle feature of the present invention relates to a polygonal 
construction module comprising a body portion having edge faces, a top 
face and a bottom face with each of the edge faces having a plurality of 
outwardly projecting fingers of square or rectangular cross-section. The 
fingers are designed to provide a snap-together lateral interlock between 
fingers of adjacent modules while permitting hinging or rotation between 
modules while permitting hinging or rotation between modules on an axis 
parallel to the side face. Mating shaped portions on the body top and 
bottom faces provide face-to-face joining between modules. 
According to an important feature of the invention, the top face of each 
module has projecting upwardly therefrom at least one annular connector 
element for establishing a friction fit with a like connector element in 
face-to-face interlocking engagement. The connector element includes a 
series of projections arranged in a uniform circular array, each 
projection being segmental in shape with radial side walls. The space 
between each pair of projections is the same shape and size as each 
projection whereby to snuggly receive and hold a projection of a like 
connector element solely by frictional contact between engaging projection 
side walls. The body portion directly beneath each connector element is 
thin relative to the height and width of each projection to thereby 
provide the array as a whole with substantially greater flexibility than 
the intrinsic flexibility of each projection. In this manner, dimensional 
inaccuracies of the projections are accommodated when engaged with a like 
connector element, thereby enhancing the firmness of frictional contact 
between engaging projection side walls. 
In order to mold attractive modules having smooth, glossy surfaces, a 
plastic is used which is relatively stiff and has a relatively hard 
surface. A typical plastic for this purpose is ABS. Each connector element 
preferably has an outer diameter of about 10-20 mm and it is also 
desirable to use a small number, e.g. fewer than 10, segmental projections 
in each connector. Also for a firm friction interlock between connector 
elements, each segmental projection preferably has a height at least equal 
to the height of the body portion edge face, with a height of 3.5 mm to 
5.0 mm being particularly preferred. Such projections have substantial 
stiffness, but it has been found that the array of segmental projections 
as a whole can be provided with substantial flexibility by mounting them 
on a relatively thin support base. This flexibility can accommodate 
dimensional inaccuracies of the projections when engaged with a like 
connector element and enhance the firmness of frictional contact between 
engaging radial side walls. The ratio of support base thickness to 
projection height is preferably less than 1:4. 
This design has the special advantage that because of the resiliency of the 
supporting base for the projections, the modules can easily be joined or 
separated by a child, while not accidentally separating. 
The edge joining system is a snap and secure hinging joint, i.e. by means 
of mating convex projections and concave depressions, which permits 
infinite dihedral angles. The edge length of each polygon is usually an 
equal multiple of the base unit edge length. This system is capable of 
producing innumerable regular and irregular polygons, polyhedra, and 
clusters of polyhedra in space filling arrays and open packing arrays. The 
shapes and forms created with the components of the system are 
intrinsically spatial and geometric, paralleling high-tech structures, 
futuristic space-age forms and elemental crystalline forms. Thus, it 
provides a creative and educational building toy. 
The modules of the present invention provide an omnidirectional, polyhedral 
toy building system. The modular units are principally planar, simple 
polygon shapes which fasten together edge-to-edge and/or face-to-face. 
Usually, each module has an over all thickness to edge length ratio of 
less than 1:8, although ratios greater than 1:8 may be used for some 
purposes. 
The edges of each polygonal module have a linear series of projecting 
fingers symmetrically congruent to each side of the regular polygon module 
and to each equal length side in the case of irregular polygon modules. At 
least one projecting finger has a convex projection on one side and at 
least one finger has a corresponding concave depression on an opposite 
side. Alignment of the projecting fingers is such that the fingers and the 
space between the fingers on the side of one polygon inversely match any 
side of another polygon. Pressing the fingers of two polygons together 
joins them into a snap-secure interlocking hinge joint which can be 
dismantled by pulling the pieces apart. 
The same sequence of interlocking projecting fingers or equal multiples 
thereof are symmetrically arranged along each modular polygon providing 
edge-to-edge matching of the modular units with one another. It has been 
found preferable to use three or four fingers along each edge face. 
The number of segmental projections in each connector element and the 
number of fingers along each edge face can vary widely. However, for ease 
of construction and ease of use of the modules, six projections per 
connector element are preferably used. 
The annular connector elements are a particularly important feature of the 
invention, in that they permit not only face-to-face connections, but also 
make possible the connection of many auxiliary components. Thus, they may 
be used as a means for attaching columns, axle supports, pivotal arms, 
ball and socket joints, etc.

Referring now in more detail to the drawings, and particularly to FIGS. 
1-4, there is shown a basic polygonal construction module 10 of triangular 
configuration and having a generally planar body portion 11. Projecting 
from the three lateral edges of this planar triangular body are a series 
of outwardly projecting fingers 12 of square or rectangular cross-section. 
The edge faces of these fingers 12 have mating concave depressions 13 and 
convex projections 14 arranged as shown in FIG. 2. 
These modules connect edge-to-edge in a hinged fashion by means of the 
projections 14 and the depressions 13 and can also be connected together 
in a face-to-face configuration by means of connector elements 19. 
The connector element 19 consists of upwardly extending segmental 
projections which are radially, equally spaced in a circular 
configuration. As can be seen from FIG. 3 and 4, the bottom face of this 
module has a star-shaped recess 20 and the top of this recess forms the 
thin base for the projections. The top face of the module also has an 
indentation or scoreline 18 formed inset a short distance from the three 
edges of the module. 
A particularly preferred embodiment of the invention is shown in FIGS. 5 to 
8. This module 60 has a planar top face 61 surrounded by a downwardly 
projecting edge flange or rim 64 defining the edge face of the module. 
This edge face includes laterally projecting fingers 62 with gaps 63 
therebetween, with the rim 64 forming the edges of the fingers 62 and gaps 
63. In association with each edge group of fingers, there is at least one 
concave depression 68 and at least one convex projection 69 to provide the 
lateral interlock between fingers. 
Projecting upowardly from the top face is an annular connector element 66 
consisting of a series of segment shaped projections. Also projecting 
downwardly from the bottom of the module is a circular flange 65 which 
forms a bottom socket or recess 67. This socket 67 has a diameter 
corresponding to the diameter of a connector 66 such that the connector 
will snugly fit within the socket 67. Also, corresponding projections from 
different modules will connect with each other. 
The embodiment of FIGS. 5 to 8 is particularly advantageous in that the 
entire module is made from relatively thin plastic material. This is 
particularly advantageous at the molding stage and assists in the 
production of a module of very precise dimensions. 
A square module compatible with the triangular module 60 of FIG. 5 is shown 
in FIG. 9. This module 70 has a planar body portion 71 with each of the 
four edges having projecting finger portions. These include a corner 
projection 72, a central projection 73 and a third projection 74. Each 
corner projection 72 has a convex projection 75 on the inner edge thereof 
and each projection 74 has a concave depression 76 on the outer edge 
thereof. The planar body portion 71 has a hole 77 extending therethrough. 
This hole 77 has a diameter which snugly receives the connector element 
66. 
A rectangular module compatible with the triangular module of FIG. 5 is 
shown in FIG. 10. This module 80 has a planar body portion 81 with 
projecting fingers on the two opposite long sides only. These projecting 
fingers include a corner portion 82, a central portion 83 and a third 
portion 84. The inner face of each corner portion 82 has a convex 
projection 85 and the outer face of each third portion 84 has a concave 
depression 86. 
One of the auxiliary components which can be connected by way of the 
connector 66 is shown in FIG. 11. This is a short column 90 composed of 
back-to-back connector elements 91 mounted to a central web portion 92. 
It is also possible to form a long column member as shown in FIGS. 12 and 
13. The column member comprises a tube 95 and end portions 93 having 
segmental projections 91 extending from one face thereof and an annular 
rim 94 projecting from the other face thereof. The annular rim 94 fits 
snuggly within the tube 95, this tube 95 being of any desired length. 
The versatility of the connector element of the invention is further 
illustrated in FIGS. 14 to 20. An arm member 100 is shown in FIG. 14 and 
this includes the planar body portion 101 surrounded by an edge rim 105. 
At one end of the body portion is circular hole 102 surrounded by a rim 
and at the other end is an elongated hole 104, again surrounded by a rim. 
The surrounding rim of hole 102 includes slots 103. 
FIGS. 16 and 17 illustrate a hub cap 96 consisting of a planar body portion 
98 with segmental projections 97 extending from one face thereof. 
Additional projections 99 may be provided which lock in the slots 103 of 
arm 100. The projection of hub cap 96 are adapted to mate with the 
projections of the construction modules, such as the triangular module 60. 
Thus, the hub cap 96 and the triangular module may be joined in the manner 
shown in FIG. 19. It is also possible to join two triangular members 60 in 
the same manner as illustrated in FIG. 18. 
It will be seen from FIGS. 18 and 19 that when components are joined by 
interconnection of segmental projections, a complete circular hub is 
formed which may then become a pivot point for mounting wheels, pivotal 
arms, etc. 
This is better seen in FIG. 20 where two arms 100 are being connected. Here 
the circular hole 102 of the lower arm 100 has been placed in register 
with the elongated hole of the upper arm 100. A hub cap 96 has been placed 
in position from the bottom and the full connection of the two arms 100 
can be completed by joining to the hub cap 96 either a further hub cap 96 
or a triangular module 60. 
The circular hole of the upper arm 100 contains the annular connector 
element of a triangular module 60 and this module 60 can be rotatably held 
within hole 102 by means of either a second triangular module 60 or a hub 
cap 96 interconnected by way of annular connector elements. 
While various changes may be made in the detail construction, it shall be 
understood that such changes shall be within the spirit and scope of the 
present invention as defined by the appended claims.