U.S. patent number 3,597,874 [Application Number 04/815,614] was granted by the patent office on 1971-08-10 for releasably interlocking units having a snap connection.
Invention is credited to Charles S. Ogsbury, Don C. Witte.
United States Patent |
3,597,874 |
Ogsbury , et al. |
August 10, 1971 |
RELEASABLY INTERLOCKING UNITS HAVING A SNAP CONNECTION
Abstract
In a toy construction set, coordinated toy units are
characterized by connectable members which radiate outwardly from
common support and terminate in enlarged end portions of generally
spherical shape and are so constructed and arranged that any pair
of enlarged end portions will releasably interlock with a pair of
enlarged end portions on another toy unit disposed at right angles
thereto; or interlock with other toy members to make up a variety
of geometric shapes. The enlarged end portions with modifications
such as opposed concave recesses permit the end portion of one unit
to snap between a pair of end portions on another unit or an
elongated shaping for the end portion provides suitable spacing for
right angle connections. A single enlarged end portion and a hollow
cylindrical hub, each preferably being slotted or hollow and of the
same external dimension permits either to serve as a male or female
coordinated locking joint portion for the toy units.
Inventors: |
Ogsbury; Charles S. (Gold Hill,
CO), Witte; Don C. (Boulder, CO) |
Family
ID: |
25218313 |
Appl.
No.: |
04/815,614 |
Filed: |
April 14, 1969 |
Current U.S.
Class: |
446/104; 446/116;
446/124; 446/113; 446/120; 446/125 |
Current CPC
Class: |
A63H
33/065 (20130101) |
Current International
Class: |
A63H
33/04 (20060101); A63H 33/06 (20060101); A63h
033/08 () |
Field of
Search: |
;46/29,30,31,26,27,28,23,25 ;35/18.5 ;16/171
;24/206,208.3,21TR,21S,23RF ;63/4 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
848,932 |
|
Sep 1960 |
|
GB |
|
1,135,362 |
|
Dec 1968 |
|
GB |
|
597,530 |
|
Aug 1959 |
|
IT |
|
597,531 |
|
Aug 1959 |
|
IT |
|
Primary Examiner: Shay; F. Barry
Claims
What we claim is:
1. A toy unit for toy construction sets comprising a generally
cylindrical hub support and connecting means radiating out in a
common plane at right angles to the longitudinal axis of said
support on said support for connection with other similar toy
units, said connecting means including a plurality of connectable
members projecting outwardly from said support, each connectable
member terminating in an outer enlarged end portion having
generally convexly spherical surface areas, adjacent of said areas
being spaced a predetermined distance between one another and from
said hub support for simultaneously engaging a pair of enlarged end
portions and hub support of other similar toy units.
2. A toy unit for toy construction sets comprising a hollow
generally cylindrical hub support, connecting means radiating out
in a common plane at right angles to the longitudinal axis of said
support on said support for connection with other similar toy
units, said connecting means including a plurality of connectable
members projecting radially outwardly from the hub support, each
connectable member terminating in an enlarged outer end portion
having generally convexly spherical surface areas, adjacent of said
surface areas being spaced a predetermined distance from one
another and from said hub support for simultaneously engaging a
pair of enlarged end portions and hub support of other similar toy
units.
3. A toy unit for toy construction sets as set forth in claim 1
wherein each said connectable member includes a narrower spokelike
portion extending from the support to the enlarged end portion.
4. A toy unit as set forth in claim 1 wherein the ratio of the
distance between the centers of a pair of adjacent surface areas to
that of the radius of each of these surface areas is about
2.77.
5. A toy unit as set forth in claim 4 wherein the ratio of the
distance from a midpoint between the centers of said pair of
adjacent surface areas to the nearest common surface of the hub
support to that of each of the radius dimensions of the adjacent
surface areas is about 1.4.
6. A toy unit as set forth in claim 1 wherein said support and
connectable members are composed of a slightly resilient,
hard-surfaced plastic material formed as an integral body.
7. A toy unit as set forth in claim 1 wherein at least one of said
enlarged end portions has a pair of opposed concave recesses on
opposite sides thereof adapted to releasably interlock between
adjacent of the enlarged end portions of a corresponding set of
connectable members turned at right angles thereto.
8. A toy unit as set forth in claim 1 wherein said enlarged end
portions are generally elongated in shape and have a semispherical
section along each side, said semispherical sections being of the
same radius dimension and each is spaced a predetermined distance
from an adjacent semispherical section.
9. A toy unit as set forth in claim 2 wherein said hub extends to a
selected distance beyond the center of the unit, whereby, in said
simultaneous engagement, said hub engages and forms a support
surface area for an adjacent pair of end portions on a second
similar unit releasably interlocked thereto at right angles.
10. A toy unit as set forth in claim 1 wherein at least one of said
enlarged end portions has a radial slot extending through an outer
surface and beyond its center toward the support for releasable
connection of the unit with other toys.
11. A toy unit as set forth in claim 1 wherein at least one of said
enlarged end portions are essentially hollow.
12. A toy unit as set forth in claim 1 wherein said hub is hollow
and has an external diameter which is substantially the same
dimension as the enlarged end portions and slotted at one end for
releasable connection of the unit with other toys.
13. A toy unit for toy construction sets comprising an integral
body composed entirely of a slightly resilient and hard-surfaced
plastic material including an inner generally cylindrical hub, and
connecting means radiating out in a common plane at right angles to
the longitudinal axis of the hub, said connecting means including a
plurality of spokes radiating outwardly from the hub at equally
spaced angular intervals with each spoke terminating in an outer
enlarged end portion having generally convexly spherical surface
areas, said end portions being essentially identical in size, each
said spherical surface area having its center an equal distance
from the center of the hub, each pair of spherical surface areas on
adjacent end portions being spaced a predetermined distance from
one another and from the hub for simultaneously engaging a pair of
enlarged end portions and hub of other similar toy units disposed
at right angles thereto.
14. In a construction set, first and second toy units, each unit
including coupling means adapted to interlock when said units are
disposed at right angles to one another, said first unit having a
cylindrical hub support, said first unit coupling means including a
plurality of connectable members projecting outwardly from the
associated hub support with each connectable member terminating in
enlarged outer end portions having generally convexly spherical
surface areas, adjacent of said end portions being slightly
yieldable one from the other and the adjacent surface areas thereof
supported a predetermined distance one from the other, said second
unit coupling means having connectable members similar to the first
unit, the spacing between an adjacent pair of said surface areas on
the first and second units being less than sufficient to permit the
end portions to slide past one another when turned at right angles,
the yieldable support permitting end portions of the two pairs to
forcibly expand and slide past and then contract one toward the
other to releasably interlock one unit with the other, said hub
support extending to a selected distance from the center of the
first unit to engage a pair of the end portions of the second unit
and provide another support surface area for the first and second
interlocking units.
15. In a construction set, first and second toy units, each said
unit including coupling means adapted to interlock one with the
other when said units are disposed at right angles to one another,
said first unit having a support member, said first unit coupling
means comprising a plurality of connectable members projecting
radially outwardly from the associated support member, each said
connectable member terminating at its outer end in an enlarged end
portion having generally convexly spherical surface areas, said
surface areas of adjacent end portions being spaced a predetermined
distance one from the other, said second unit coupling means having
similar connectable members having an enlarged end portion with a
pair of opposed spherically shaped concave recesses in the end
portions thereof to forcibly fit between a pair of adjacent end
portions of the first unit when the units are turned at right
angles to one another and permit relative rotational movement
between said first and second units toward and away from one
another.
16. In a construction set as set forth in claim 15 wherein the
opposed recesses are joined by a cylindrical hole of a lesser
diameter extending through the associated end portion to make it
essentially hollow.
Description
This invention relates to construction toys and more particularly
to novel and improved releasably interlocking toy units which are
adaptably suited for assembly into a wide variety of composite
structures either by interconnection with one another or connection
to other toy members, and is related to our copending application
entitled Construction Toys and Radial Arms Having Male Connector
Portions Therefor.
Toy construction sets or building sets composed of large numbers of
interfitting toy units are entertaining and may be highly
instructional to the user. These sets challenge the creative
ability of the user which is usually a child according to the
possible interconnections and the degree of mechanical strength
which the individual units afford. Some of the earlier toy sets
were composed of wood and did not have the durability or
flexibility of the newer plastic materials. Some plastic toy sets
have heretofore been provided but have not made full utilization of
the durability and flexibility of plastic materials to provide a
toy construction set having maximum durability and versatility.
Accordingly, it is an object of this invention to provide a simple,
durable and easy-to-assemble toy unit and a fully coordinated set
of units which are capable of being assembled into a wide variety
of geometric and random structures.
Another object of this invention is to provide toy units preferably
composed of plastic or plastic-surfaced materials having strong
interlocking joints which permit large numbers of units to be
assembled one with the other while maintaining a definite position
in the assembly together with full ease of assembly and
disassembly.
Yet a further object of this invention is to provide a novel and
improved toy unit in which a plurality of basically similar
connectable members will interlock one with the other to minimize
the cost of manufacture and wherein a slight modification and
variation in connectable members and the units will greatly
increase the number of possible combinations and shapes of
composite structures which may be attained.
Still a further object of this invention is to provide a novel and
improved toy unit which fully utilizes characteristics of molded
plastic material to provide a toy unit with connectable members
having spherical shaped enlarged end portions having smooth
surfaces which is pleasing to touch and will produce an audible
snap between members when they have been firmly interlocked into
place.
In accordance with the present invention there is provided fully
coordinated releasably interlocking toy units each comprising an
inner hub and a plurality of connectable members radiating from the
hub with each connectable member terminating in an enlarged end
portion. Adjacent of the end portions are spaced a predetermined
distance one from the other and from the hub in order to snap
together in a releasable interlock with other toy units disposed at
right angles thereto. A radial arrangement of a selected number of
enlarged end portions, such as, four, six or eight will interlock
with correspondingly spaced end portions on other toy units at
right angles to one another and enable several toy units to be
interlocked in a radially spaced array outwardly from a single toy
unit and will enable the assembly of straight line, right angle,
and a wide variety of geometric configurations. Modification in the
enlarged end portions such as opposed concave recesses permits one
end portion to snap fit between adjacent end portions and an
elongated shaping for the end portions provides suitable spacing
for right-angle connections to greatly increase the flexibility of
a set of the toy units. A single enlarged end portion and a hollow
cylindrical hub both having an end slot or the end portion being
hollow which are of the same external dimension and serve as added
male or female coordinated locking joint portions for the toy
units.
Other objects, advantages and capabilities of the present invention
will become more apparent as the description proceeds taken in
conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of two identical circular toy units
interlocked with one another which embody features of the present
invention.
FIG. 2 is an elevation view of the interlocked toy units shown in
FIG. 1 with a portion of one broken away to avoid unnecessary
duplication and a third similar unit shown in dashed lines.
FIG. 3 is an elevation view showing the relationship of the
interlocking sets of enlarged end portions of the two toy units
shown in FIGS. 1 and 2 with the hub of one and spokes of both
removed for clarity.
FIG. 4 is an elevation view illustrating a modified form of toy
unit having opposed concave recesses, with portions of two toy
units being interlocked on a similar intermediate toy unit.
FIG. 5 is an elevation view of another form of toy unit.
FIG. 6 is a sectional view taken along lines 6-6 of FIG. 5.
FIG. 7 is a top plan view showing two toy units of a modified form
being interlocked with a sheet of material having spaced apertures
in which either the hub or an end portion of the toy unit
frictionally interfit.
FIG. 8 is a side elevation view of the assembly of FIG. 7.
FIG. 9 is an elevation view of another form of toy unit embodying
features of the present invention having modified elongated
enlarged end portions which permit four-way or right-angle
connection between units.
FIG. 10 is a sectional view taken along lines 10-10 of FIG. 9.
FIG. 11 is an elevation view of another form of toy unit having
true spherical shaped end portions of the same radius dimensions
providing two-way connection for other similar toy units at
180.degree. intervals to one another; and
FIG. 12 is a sectional view taken along lines 12-12 of FIG. 11.
Referring now to the drawings in FIGS. 1--3 there is shown a pair
of interlocked generally circular toy units 11 and 12 embodying
features of the present invention. Units 11 and 12 are shown for
illustration purposes and correspond in size and shape so that the
description of the details of one apply to both. Generally stated,
each circular toy unit has outwardly disposed spherical shaped
enlarged end portions or balls 13 which for the units 11 and 12 are
arranged at 60.degree. intervals with their centers in a common
plane and supported about a central axis or center 0. These units
comprise a common hub 14 and connecting means radiating out in a
common plane at right angles to the longitudinal axis of the hub in
the form of a plurality of connectable members including an
elongated spoke 15 extending radially outwardly from the hub which
terminate in the enlarged end portion 13. The hub is cylindrical
and preferably provided with a hole or is hollow and extends
transversely to a common plane through the centers of the balls
13.
The toy connector unit having six connectable members as
illustrated in FIGS. 1--3 has a basic dimension, construction and
arrangement of parts which are carried forward to make up a fully
coordinated set of similar toy units suitable for assembly into a
wide variety of essentially rigid composite structures. One of the
interlocking capabilities of the unit having six radiating
connectable members as well as those with four or eight toy units
described hereinafter is that with the dimension and spacing
relationships of the enlarged end portions hereinafter set forth to
permit any one of them to interlock at right angles to another as
is illustrated by units 11 and 12 in FIGS. 1--3. In this way a
straight chain of units may be constructed or a variety of
geometrical configurations radiating from the center of one unit
can be constructed. For example six units will connect radially
outwardly from a single unit at 60.degree. angularly spaced
intervals on the unit 11 which may be understood with reference to
FIG. 2 by unit 12, and in dashed lines by a second unit 12a; the
two units 12 and 12a not interfering with one another.
Each pair of adjacent enlarged end portions 13 of a radius
dimension designated r are arranged on an equal distance from
center to center and spaced one from the other to provide sets of
opposed and spaced convexly spherical or spherical-shaped surfaces
or surfaces areas 16 and 17. The adjacent radiating spokes 15 which
are of a substantially lesser diameter than the end portion provide
inwardly convergent surfaces 18 and 19 inwardly of the ball 16 and
17 respectively. These opposed surfaces define an essentially
arrow-shaped slot which may be utilized to hold other toy members
such as a cylindrical rod preferably of plastic which will snap
between surfaces 16 and 17 (not shown) to illustrate another common
member which can be secured to the basic toy unit 11 herein
described. The spacing between the centers of the adjacent surfaces
or surface areas of the spherical-shaped end portion members is the
same for all adjacent end portions and is designated R. Generally
speaking the spacing R between the adjacent end portions will not
pass a similar set of opposed semispherical surfaces disposed at
right angles as is best shown in FIG. 3. This spacing is selected
so that such resiliency of each set of adjacent end portions and
their smooth double curved surfaces permits them to expand or
spread slightly as one set of end portions is pressed against the
other. However once the two sets of end portions pass the area of
minimum spacing each set of opposed surfaces slightly overlap that
of the other to provide contact points between adjacent balls
arranged about a center C; the contact points serving to prevent
the two elements from separating from each other. In addition,
adjacent end portions have surface areas with centers which are
disposed from a line M a selected distance from a line R parallel
to line M; line R passing between the centers of adjacent end
portions being spaced from line M a distance designated X. This
distance X may also be characterized as the perpendicular distance
from the midpoint of the line R extending between centers of the
convexly spherical surface areas of two adjacent end portions to a
parallel line M which is tangent to the surface of hub 14. The hub
of a radius dimension r will establish a contact point located a
distance X from the line through the center of the end portions to
limit the inward movement of an interlocking set of end portions of
a second toy unit to only a slight distance beyond areas of minimum
spacing between the adjacent sets of end portions. The dimensional
relationship which provides best results for a fully coordinated
set of units is a ratio of R/r of about 2.77 and a ratio of X/r of
about 1.4; this places the gap or space between adjacent end
portions of 0.77 times the radius r of the enlarged end
portion.
The dimensional relationships of a toy unit may be derived using
the geometric relation of the end portions of FIGS. 2 and 3 with
reference to a three-dimensional coordinate system. The set of
interlocking end portions of unit 11 are designated 13a and 13b and
of unit 12 are designated 13d and 13c. The center of end portion
13b is A and the center of end portion 13c is B. The origin of the
coordinate system is selected to be at C which is equally spaced
between the centers of end portions 13a and 13b and also 13c and
13d, and the elevation of the center B above A through the origin C
is at D. This places distance AC along one axis, distance CD along
a second axis and distance DB along a third axis of a
three-dimensional coordinate system. Using the general equation for
a distance in space, the distance between the centers of two
adjacent end portions 13b and 13c or distance AB is equal to the
square root of the distance AC squared, plus distance CD squared,
plus distance DB squared. Substitution of the corresponding values
of R and r in the symmetrical six-member arrangement will produce
the above dimensional relationships of R/r and X/r. These
relationships may be carried forward into a variety of
multiple-number configurations including four, five, six and eight
connectable member structures, all of which will interlock at right
angles with one another. Referring now to FIG. 4 there is shown a
modification in the six-member construction above described wherein
portions of two toy units 21 and 22 are constructed and connected
to or interlocked to a central toy unit 23, the three units being
identical. Each spherical end portion in this form has a pair of
opposed spherical concave recesses 24 and 25 located generally at
right angles to the convex surfaces which form joint portions for
interlocking sets of enlarged end portions at right angles as above
described so that they do not interfere with the interconnections
of the convex contact surfaces 16 and 17 above described. Recesses
24 and 25 permit the end portion of one element 21 to be
interlocked between the opposing convex surface of unit 23 and
permit the rotation of one unit toward and away from the other unit
as best shown between elements 22 and 23.
As shown with reference to unit 23 these opposed concave recesses
24 and 25 are in a radial alignment with the spokes and centers of
the spherical end portions and have the same concavity as the
radius of the convex spherical surface which fits therein. The
centers P of the recesses as viewed in elevation are spaced
slightly radially outwardly from that of the associated spherical
end portion on which they are formed and the effective radius
designated b and measured from P of the recess is less than the
spherical radius r of the end portion. The recesses 24 and 25 are
preferably joined by a hole through the spherical portion which
makes them essentially hollow; the holes for the unit preferably
having a radius c which is less than b to provide a concave
spherical surface but is recognized that if the radius of the hole
c was increased to that of the recesses 24 and 25 or b that this
would be effective in forming opposed recesses which would also
permit the interconnection of the units 21, 22 and 23 as shown. The
holes 26 are effective in permitting the spherical end portions to
contract under compressional forces so they will effectively yield
to snap fit into an apertured sheet or the like as is illustrated
herein with unit 41 in FIGS. 7 and 8, and for the basic six-member
permits as many as six similar units to be connected to a single
unit and provides a frictional fit which permits one unit to be
forcibly rotated toward and away from the other to give added
flexibility to the set and is particularly suitable for joint
structures such as for legs or animals and the like.
With a general reference now to FIGS. 4, 7 and 8 it is apparent
that either the opposed concave recessed portions 24 and 25 and
hole 26 in the ball and the radial slot 46 will not interfere with
each other or with the opposed convex surfaces so that all may be
provided on the same toy element surfaces 16 and 17.
The eight-member form of unit 30 shown in FIGS. 5 and 6 has the
same dimensional relationships of radius r, distance R and distance
X above described with eight connectable members arranged about a
modified hub 31 with radially extending spokes 32 between the hub
and spherical end portion 33. The hub being considerably larger for
the eight-member configuration and preferably has an internal
diameter which will frictionally receive the hub 14 of the
six-member toy unit. This eight-member structure has the same
dimensional relationships as the six-member unit and permits it to
receive eight units having outwardly disposed sets of spherical end
portions as above described at right angles thereto and will
dispose and hold them at 45.degree. angles.
A toy assembly in FIGS. 7 and 8 includes a pair of toy units 41 and
42 releasably interlocked with a thin sheet of material 43 having a
series of spaced apertures 44 to illustrate how a single enlarged
end portion and the hub may be utilized as connectable members.
Each of these units 41 and 42 are identical to each other. The same
toy units 41 and 42 have the dimensioning of the spherical end
portions, hub and spokes as that above described with references to
FIGS. 1 to 4. The end portions 45 of each unit have a radial slot
46 which extends substantially beyond the center of the sphere to
divide it into a pair of opposed spherical sections 45a and 45b
which are supported on a common spoke 47. The combined external
dimension or diameter of these spherical sections is slightly
larger than that of the aperture 44 in the sheet but the slotted
construction provides an added degree of resiliency to permit them
to yield when fitted into the aperture so that the spherical
surfaces will first contract and will then expand when in place to
the original position once they are moved into the aperture 44 past
the center of the sphere for a snap-on fit. The thickness of the
sheet of material 43 is selected so that the outer surface does not
extend beyond the center of the sphere or ball 45. In this manner
the sheet of material will snap onto the opposed semispherical
sections and the undersurface of the adjacent ball sections will
support the sheet in position as shown. The thickness of the sheet
is coordinated with the thickness of the slot 46 to also permit the
sheet 43 to slide into the slot for added versatility. The hub 48
of these elements has a radial slot 49 which also affords an added
degree of resiliency to the hub to permit the hub which is of
essentially the same radius as the ball to slip into any of the
apertures 44 in the sheet with the hub being under slight
compression to hold it in place. The hole or aperture in the hub is
designed so as to fit loosely on part of a cylindrical rod for
rotational movement thereon and may be provided with an inturned
opposed lip at one end along its interior surface so that the hub
will fit tightly on the rod when it is placed all the way on the
rod for upright support of the element and added versatility.
The four-way, four-member unit 51 shown in FIGS. 9 and 10
illustrates one possible variation in the shape of the enlarged end
portions of the connectable members from that of a true sphere.
Four identical elongated enlarged end portions 52 are disposed at
90.degree. intervals about a solid hub 53 which extends
transversely to the connectable members; each end portion being
supported by a narrower radially extending spoke 54. The enlarged
end portions 52 include an elongated cylindrical intermediate
portion 52a and semispherical shaped portions 52b and 52c at each
end. The space between the surface areas 56 and 57 of adjacent end
portions are of a radius r as measured from center to center
thereof is a distance R and a radial distance X extends from the
hub to the midpoint of the distance line R; these distances r, R
and X having the same dimensional relationships as above described.
It is also noted that the centers of the semispherical portions 52b
and 52c are spaced one from the other an equal distance on opposite
sides of a radial line passing through the center of the spoke. As
illustrated by elements 58 and 59 represented in dashed lines this
form of connector element permits two units to be held at
90.degree. intervals to one another or a total of four units on a
single unit and will provide a right-angle or four-way unit, as
required. The other form of four-way unit shown in FIGS. 11 and 12
comprises four spherical end portions 62 of a radius r supported by
radial spokes 63 for each end portion; the spokes 63 merging
together in the center and this form does not require a
transversely extending elongated hub. The same R, r and X
relationships are utilized for coordinated set units. This form
permits only the connection of two units 64 and 65 shown in dashed
lines at 180.degree. to one another because there is not sufficient
circumferential spacing to connect two more units while two are in
place as shown. The interlocking units are at 180.degree. and may
engage each other on each side or adjacent spokes as 63a and 63b
may form a seat on each side for the interconnecting pair of
spherical end portions of one unit to provide other points of
contact or stop support surfaces to form locking joints without the
necessity of elongated cylindrical transverse hubs.
The toy units as above described are preferably formed as an
integral body composed entirely of a hard-surfaced, slightly
resilient plastic material such as polypropylene in one of a
variety of bright colors. The units illustrated herein may
advantageously be formed by injection molds without coring. The
juncture of spokes and the hub are preferably filled in or
thickened or radiused for added strength to avoid breakage. While
the spoke-type extensions for the enlarged end portions have been
shown it is understood that other forms of structure such as a
web-type structure may be provided for a similar radial disposition
of enlarged end portions about a common center. The plastic
material such as polypropylene has a slight resilience which
permits the opposed spherical sections to be expanded and contract
a slight degree to facilitate a snap action and a rigid
interlocking of the units.
From the foregoing it is apparent that the various toy units using
connector members with spaced spherical shaped enlarged end
portions hereinabove described afford a wide degree of flexibility
for making up composite structures. These units when composed of a
hard, smooth plastic material with slight resiliency such as
polypropylene may be made in bright colors to provide a striking
appearance. The interlocking hubs and spherical-shaped surfaces one
with the other will provide a snap action or audible click which is
pleasing to the user and especially children which indicates that
the units are firmly interlocked in place. These spherical-shaped
end portions permit the units to be assembled and disassembled with
ease and yet once in place provide a composite structure of
substantial rigidity. Units constructed in accordance with the
present invention may be assembled to make up random structures
such as a tree or a variety of geometrical configurations due to
the geometry of the arrangements shown. The geometric relationships
of these units may be highly instructional for making molecular
structures and the like.
Although the present invention has been described with a certain
degree of particularity, it is understood that the present
disclosure has been made only by way of example and that changes in
details of structure and materials may be made without departing
from the spirit thereof.
* * * * *