Claims:
What is claimed is
1. A device of the type described, comprising a series of identical pyramidal forms each having an isosceles triangular base and three isosceles triangular upright sides connected at the bottoms thereof to the respective edges of said base, the forms of said series being flexibly articulated thereto at successive adjacent base edges, whereby with said bases disposed coplanar with one another said forms lie in a parallel-sided linear array.
2. The device of claim 1, in which said bases are equilateral triangles and said upright sides are identical right triangles, said series thereby being rectilinearly parallel-sided along edges of said bases other than the flexibly articulated base edges.
3. The device of claim 1, and further comprising flexible tape means secured to the bases of said series of forms and spanning said articulated base edges.
4. The device of claim 2, and further comprising flexible tape means secured to the bases of said series of forms and spanning said articulated base edges.
5. The device of claim 2, in which said forms are of hollow section.
6. The device of claim 4, in which said forms are of hollow section.
7. The device of claim 2, in which said forms are of solid section.
8. The device of claim 4, in which said forms are of solid section.
9. The device of claim 2, in which said forms are of molded plastic material.
10. The device of claim 4, in which said forms are of molded plastic material.
11. The device of claim 7, in which said forms are of molded plastic material.
12. The device of claim 8, in which said forms are of molded plastic material.
13. The device of claim 1, in which said forms are a multiple of four in number which is sufficient to enable the production of flexibly articulated polyhedra, each constituted by a flexible manipulation of four of the forms.
14. The device of claim 2, in which said forms are a multiple of four in number which is sufficient to enable the production of flexibly articulated cubes, each constituted by a flexible manipulation of four of the forms.
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
As indicated by the title, the device may be utilized as an educational and/or amusement product for the edification of old and young alike, being accordingly marketed in specialty or department stores, scientific and/or educational display outlets, etc.
2. Description of the Prior Art
A search has revealed the following patents:
Kennedy 538,261 Apr. 30, 1895 Chambers 1,471,943 Oct. 23, 1923 Hopkins 2,992,829 July 18, 1961 Resch 3,201,894 Aug. 24, 1965 Klein 3,565,442 Feb. 23, 1971 Thompson 3,628,261 Dec. 21, 1971 Freedman 3,662,486 May 16, 1972
23,
Of the above, Hopkins is most pertinent in its disclosure of a number of flexibly articulated, similar and irregular polyhedral forms, including pyramids capable of combination in one way or another, but not different cubic assemblies of four regular tetrahedra as described in the Abstract.
SUMMARY OF THE INVENTION
As composed of a flexibly articulated rectilinear series, succession or array of identical equilaterally triangle-based, 90° triangle-sided pyramids, the improved device has many aspects or outlets in various imaginative and not-so-imaginative types of use. Typically, for instance, it may be a manipulative toy for youngsters to stimulate the imagination, or it may serve to challenge the inventiveness of the older, for example, as a test of how many different combined forms may be produced, preferably cube-composed and employing all of the tetrahedral pyramid components. Another suggested use is in the making of display or presentation models, as assemblies of cubes temporarily or permanently held together adhesively or otherwise. Many other modular possibilities or potentialities are present. Indeed, the device offers a significant amusement and instructive use simply in the guise of a puzzle requiring a solution of a nonobvious manner in which the pyramid forms are to be assembled to produce an illustrated ultimate combination. Many free-form compositions, in which composite juxtaposed pyramids do not all necessarily outline like cubes, have been mentioned as a possibility.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a top plan view or layout of the device in its flat developed form;
FIG. 2 is a side elevation of said device as shown flexibly backed and articulated by suitable tape or ribbing;
FIG. 3 is a bottom plan view of the unit, showing an arbitrary marking of the pyramids from 1 through 16 which has been adapted solely to assist in a description to follow of an intended manipulation of the device; and
FIGS. 4-7, inclusive, are perspective views showing combinations in different outlines of composite, pyramid-constituted cubes, as contemplated by the invention.
DESCRIPTION OF A PREFERRED EMBODIMENT
The amusement and educational device of the invention is generally designated in FIGS. 1, 2 and 3 by the reference numeral 10, and takes the form of a rectilinear, parallel-sided series of pyramids. As such, it is constituted in its entirety by a number of identical pivotal, tetrahedral or triangle-base pyramids 12, typically shown as sixteen in number, although any whole multiple of four is contemplated. Each is formed by three identical, upright isosceles-triangular sides 13, 14, 15, plus a bottom isosceles-triangular base 16; and, pursuant to the invention's essence, the sides 13, 14 and 15 are 90° or right angle triangles whose base edges are of the same length as the edges of the base 16, which is an equilateral, 60° triangle.
If desired, the pyramid surfaces 13-16 may be transparent or opaque, or colored in different contrasting hues, key-coded or not; more importantly, it is contemplated that said pyramids be rigid-sided as molded of a suitable plastic composition. Furthermore, they may be of solid or hollow internal section; and the tetrahedral edges of an individual pyramid piece may be integrally, adhesively or otherwise rigidly connected to define a four-sided, triangular-base pyramid.
As appears in FIG. 3, adjacent successive edges of the forms 12, as designated 17 in FIG. 3, are in the form and have the effect of pivotal connections intersecting one another at 60°; and as appears in FIG. 1, corresponding opposite triangle side surfaces 15 extend parallel to one another in common inclined planes. Extreme end pieces of the series, as specially designated 12', have their external free base edges 17' in parallel relation to one another.
As laid out in the individual shapes and overall relationship described, the pyramidal forms 12 are flexibly articulated to one another in an appropriate manner, preferably by a continuous elongated tape or ribbing part 18 (FIGS. 2 and 3), such as of a pressure sensitive adhesive- coated plastic tape, or an adhered canvas or other cloth or the like, depending upon the intended use. Margins of this member are preferably conformed with those of the pyramidal series. Mechanical piano hinge or other free swinging connections are also contemplated, although of course adding to cost.
FIGS. 4, 5, 6 and 7 depict optional ways in which the device 10 may be manipulated to attain objectives mentioned in the Summary. FIG. 4 illustrates a straight line arrangement, designated 20, of four cubical components 21, 22, 23, 24, each constituted by four of the sixteen forms 12 of the device. As indicated above, the last named number may be any whole multiple of four, as it is desired to increase or decrease the number or type of ultimate layouts.
In proceeding to produce the basic rectilinear arrangement 20 (FIG. 4) of the pyramid device 10, let it be assumed that the selected sixteen pyramid forms 12 thereof, solely for the present purpose of description, be arbitrarily numbered sequentially end-to-end, as shown in FIG. 3, as 1 through 16. Two intermediate pyramids 9 and 10 having been selected for a start, their respective base surfaces 16 are folded toward one another about their edge pivot connection 17 to a 60° intersecting relationship to one another, and pyramid 8 is swung inward to bring one of its sides coplanar with one of pyramid 9 to constitute a cube face. The base of pyramid 11 is similarly folded inwardly toward the thus-manipulated pyramids 8, 9 and 10, bringing free equilateral edges thereof against those of the other three pyramids, and with its base spanning pyramids 8, 9 and 10. The base edge of the right triangle of 11 edge-abuts that of right triangle of 10 as the diagonal of one side of cube 21, just as the bases of pyramids 8 and 10 edge-abut as a diagonal of the opposite square face of cube 21.
The start of the second cube 22 of FIG. 4 is by outwardly swinging a right triangle side of pyramid 12 face-to-face onto a corresponding surface of pyramid 11, as hingedly connected thereto; and by similarly swinging pyramid 7 outwardly onto pyramid 8. The equilateral bases of pyramids 6 and 13 are now swung to 60° relationship to those of pyramids 7 and 12, so that bases of 90° triangle sides thereof meet edge-to-edge as diagonals of opposite faces of the second cube 22. Exactly the same process is repeated in forming the third cube 23, involving outward and inward swingings of pyramids 14, 5, 4 and 15.
Finally, right triangle sides of pyramids 3 and 16 are swung outwardly onto like sides of pyramids 4 and 15, respectively, whereupon the bases of the pyramids 2 and 1 are sequentially swung inwardly in that order to span equilateral pyramids 3 and 16. This brings base edge surfaces of pyramids 1, 2, 3 and 16 in abutting relationship in pairs as diagonals of three faces of the fourth cube 24.
It is of course to be understood that the starting point for the above described manipulation may be at any reasonably medial point along the length of the pyramid series 10. If it is desired to produce any of the other forms of FIGS. 5, 6 and 7, the T-type 25 shown in FIG. 5 is attained by a laterally outward swing of an intermediate triangle 12 about its hinge 17 to the next adjacent one, the other three triangles appendant to the intermediate then being swung to complete the stem T.
The L-configuration 26 of FIG. 6 is reached indentically, save that the 180° laterally outward swing of a set of four triangles is at an end set of the device 10; while the bi-planar concept of FIG. 7 involves bi-lateral swing of any two selected groups of four, in the manner indicated in reference to FIGS. 5 and 6.