Structural Unit And Assembly

Abstract

A pliable structural unit which is combinable with other similar units to form a geometric assembly with multiple faces contributed by the various units. Each unit is formed from a sheet of pliable material marked to indicate how it can be folded to serve as a single polygonal face of an assembly, or provide a multiplicity of faces. The marking is illustratively made by score lines which delimit and appear on the faces of the units and tabs. Such lines facilitate the desired folds, indicate removable material on the tabs, and limit the degree of transverse bulge for units forming single faces. The tabs permit fastening to similar tabs of other units. Fastening may take place using ordinary adhesives and standard fasteners such as paper clips.

Description

BACKGROUND OF THE INVENTION

This invention relates to structural units, and more particularly, to pliable structural panels.

A structural unit is an iterated or repeated element of an overall structural assembly. One such unit is the panel which may be combined with other panels for general building purposes, or used to form geometric figures for instructional or recreational purposes.

Panels typically are of a prescribed size and are interconnected to form the desired assembly, with each panel serving as a face of the overall structure. Generally, when the type of overall structure is changed, the panels are changed as well. Thus, when the scale of the construct is altered, new panels are correspondingly required.

Accordingly, it is an object of the invention to provide flexible structural units which are adaptable for a multiplicity of purposes. A related object is to realize a multipurpose panel for constructing a wide variety of geometric objects. Another object is to achieve a structural unit which can provide more than one size of panel.

It is often desirable for structural panels to be of pliable material. This permits portions of the panels to be folded to form tabs for attaching the panels to one another. Such tabs can interfere with each other and with the panels. Moreover, the faces of pliable panels often exhibit a tendency to bulge.

Accordingly, it is a further object of the invention to provide multipurpose structural panels in which the interconnection of panels is facilitated. A related object is to prevent the tabs of such panels from interfering with each other and with other panels. Another object is to limit the tendency of such panels to bulge.

SUMMARY OF THE INVENTION

In accomplishing the foregoing and related objects, the invention provides a structural unit of pliable material with a multisided face, a tab along at least one of the sides and a fold marker in the face extending from one side to another. This permits the panel to be used as an entity or in forming subordinate faces of a geometric object with multiple faces.

In accordance with one aspect of the invention, the fold markers can extend between opposite or adjoining sides of the face.

Moreover, where the fold markers are provided by scoring the surface of the unit, the resultant depression in one surface, and elevation in the opposite surface, can limit the tendency for the face of the structural unit to bulge.

In accordance with a further aspect of the invention, the tab of the structural unit includes markers which indicate a portion that is removable when a unit is to provide a multiplicity of faces. The tab markers are oblique extensions of adjoining fold markers on the face of the unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Other aspects of the invention will become apparent after considering several illustrative embodiments, taken in conjunction with the drawings in which:

FIG. 1A is a plan view of a structural unit in accordance with the invention;

FIG. 1B is a cross-sectional view of the structural unit of FIG. 1A;

FIG. 2A is a partially completed geometric assembly employing a plurality of structural units of the type shown in shown in FIG. 1A;

FIG. 2B is a partially completed geometric construct formed from a single unit of the type shown in FIG. 1A; and

FIGS. 3 and 4 are plan views of further structural units in accordance with the invention.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Turning to FIG. 1A, a pliable structural unit 10 in accordance with the invention is illustratively formed by a panel with an equilateral triangular face 11 that is delimited within marker fold lines 12 and has marginal tabs 13. Because of its triangular face 11, the overall unit 10 is trigonal. The face 11 can be joined to other trigonal units using the tabs 13 to provide an overall assemblage of desired configuration.

In addition to the peripheral markers 12, the face 11 bears internal marker fold lines 14, which extend between the mid-points of adjoining equilateral sides and become diagonal markers 15 in the tabs 13. Each of the tab markers 15 is displaced by an acute angle a with respect to the nearest adjoining one of the internal fold lines 14. The pair of diagonal markers 15 in each of the tabs 13 defines a region of material that is removable when the trigonal unit 10 is to be used in forming more than one face of a desired assembly. The diagonal markers 15 are parallel with respective ends of the tabs 13 and are proportioned to prevent interference with other tabs or faces when several units are joined together or when a single unit is used to form multiple faces.

The tabs 13 are shown with outer edges that are parallel to the delimiting fold lines 12. It is to be understood that other forms may be employed as well, such as variously configured flaps, ribs, struts, leaves and flanges, as long as the members 13 are hingeable with respect to the face 11 and are attachable to other structural units.

As indicated by the cross-sectional view of FIG. 1B, the face markers 12 and 14, as well as the tab markers 15 (not shown), are desirably produced by scoring which results in indentations in one surface of the trigonal structural unit 10 and corresponding elevations on the opposite surface. This gives enhanced rigidity to the structural unit 10 when used as a single panel to limit the extent to which bulging takes place. The various markers 12, 14 and 15 may also be produced in other ways, for example by dashed-lines which may penetrate into a surface of the unit 10.

The material of the structural unit 10 is illustratively paperboard. However, other pliable materials may also be employed, such as corrugated cardboard, plastic sheeting, metallic sheeting and wire mesh.

A partially formed geometric assembly 20 is set forth in FIG. 2A, which makes use of structural units 10-1 through 10-7 of the type 10 in FIG. 1A. To form the assembly 20, the tabs of the constituent units are bent inwardly along their peripheral fold lines and attached to mating tabs of adjoining units using common fasteners such as paper clips 21. Other kinds of fasteners may be employed alternatively, or the tabs may be joined together using standard adhesives.

Because of the way in which the ends of the tabs are tapered, they do not interfere with other tabs or faces when folded. In addition, the score lines 14 of the units 10-1 through 10-7 tend to limit bulging by their associated panels.

The assembly 20 of FIG. 2A has seven closed faces and an eighth, open face. If the eighth face is closed by a structural unit, such as the unit 10 of FIG. 1A, the result is an eight-sided figure not commonly encountered in solid geometry. This figure is equivalent to a composite of three equilateral pyramids, two connected base-to-base and a third attached to one of the faces of the other two. Thus, by using a number of structural units of a single type, a wide range of geometric figures can be realized for pedagogic and ultilitarian purposes.

In addition to the use of structural units, such as the unit 10 of FIG. 1A, to form panels of an overall geometric assembly as illustrated by FIG. 2A, a single unit may be adapted to provide a multiplicity of panels in the manner depicted by the unit 25 of FIG. 2B.

The multipanel unit 25 is realized from the monopanel unit 10 by removal of that portion 13' (FIG. 1A) of the tabs 13 between each pair of diagonal markers 15. When the unit 25 is of paperboard or some other easily cut material, the removal of the undesired tab material is accomplished using scissors or shears to cut along the lines of the diagonal markers 15. This divides each of the tabs 13 into two parts and permits the unit 25 to be folded along the lines indicated by the interior markers 14. The result is the conversion of the monopanel unit 10 of FIG. 1A with a single face 11 into the quadrapanel unit 25 of FIG. 2B with four faces, an inner face and three outer faces 11-1 through 11-3.

As shown in FIG. 2B, the unit 25 has been folded so that one outer face 11-2 is perpendicular to the base inner face and a coplanar outer face 11-3. The remaining outer face 11-1 has been only partially folded to form an acute angle with respect to the coplanar faces. When the outer faces 11-1 through 11-3 are folded through an obtuse angle relative to the starting plane, and their tabs are pined together, e.g. in a manner similar to that employed for the composite assembly 20 of FIG. 1B, the single unit 10 of FIG. 1A forms a tetrahedron or regular pyramid. Because of the disposition of the markers 15 in the tabs 13, the divided tabs that result from removal of the material 13' do not interfere with each other or any face of the multipanel unit 25.

Although the structural units 10, 10-1 through 10-7 and 25 of FIGS. 1A through 2B are trigonal, with triangular faces, a structural unit in accordance with the invention is polygonal in general. Illustrative quadrangular and pentagonal structural units 30 and 40 are shown in FIGS. 3 and 4, respectively.

The quadrangular unit 30 of FIG. 3 has a square face 31 delineated with peripheral fold lines 32 and marginal tabs 33. On the face 31 there are internal fold lines 36 which extend between the midpoints of opposite sides and adjacent sides. Included in the tabs 33 are diagonal markers 35 which define a region 33' of material which is removed when the unit 30 is to be folded to provide a multiplicity of faces.

Similarly, the pentagonal unit 40 of FIG. 4 has a pentangular face 41 within peripheral fold lines 42 and marginal tabs 43. Internal fold lines 44 of the face 41 extend between adjacent sides and apply when the marginal material 43' is removed from between associated markers 45.

Consequently, each of the structural units 30 and 40 can be used in a manner similar to that of the trigonal unit 10 to provide either a single panel or a multiplicity of panels.

While various aspects of the invention have been set forth by the drawings and specification, it is to be understood that the foregoing detailed description is for illustration only and that various change in parts, as well as the substitution of equivalents for what is shown and described, may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Claims

What is claimed is:

1. A structural unit formed from a sheet of pliable material, comprising

a face having a plurality of sides,

a tab bounded by a fold marker adjoining at least one of said sides and extending therealong,

and a plurality of markers in said face extending between the sides thereof,

said tab including markers therein which are extensions of adjoining markers on the face of said unit and form acute angles therewith for indicating a removable portion of said tab.

2. A structural unit as defined in claim 1, wherein said markers extend between opposite sides of said face.

3. A structural unit as defined in clam 1 wherein said markers extend between adjoining sides of the said face.

4. A structural unit as defined in claim 1 wherein said markers are formed by score lines which produce a depression in one surface of said structural unit and an elevation in the opposite surface thereof.

5. A trigonal structural unit formed from a sheet of pliable material, comprising

a face having a plurality of sides, a tab adjoining at least one of said sides and extending therealong, and at least one marker in said face extending from one side thereof to another, wherein said face is triangular and said sides are equilateral, a marginal tab extends along each of said sides and has obliquely tapered ends to facilitate the attachment of said unit to other similar units,

the triangular face of said unit includes score line markers extending between the midpoints of adjoining sides, and each of said tabs includes score line markers extending divergently thereinto from the midpoint of the adjoining side of said triangular face and forming acute angles with respect to adjoining score line markers of said face.