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United States Patent [191 [11] 4,317,654 Wahl [45] Mar United States Patent [191 [11] 4,317,654 Wahl [45] Mar. 2, 11.982 [54] EDUCATIONAL BLOCKS 429509 5/1935 United Kingdom .................. ,. 46/24 [76] Inventor: Martha S. Wahl, l Huckleberry La., OTHER PUBLICATIONS Rldge?eld’ Conn‘ 06877 Cundy and Rollett, “Mathematical Models” lst Edi [21] Appl No.: 114,068 tion, pp. 94-99, 110, Ill, 114, I15, llé, ll7, Plate 2. - "Martin Gardners New Mathematical Diversion From l 22 1 F ‘led : J a“ . 21, 19 80 sciv. Am.” p. 143 only, Sep. 1966. Related US. Application Data Primary Examiner-Harland St Skogquist [62] Division of 5“ No_ 896,175, Apt “, 1978’ abam Attorney, Agent, 0rF1'rm—-St. Onge, Steward, Johnston, cloned‘ Reens & Noe [51] Int. (:1.3 ........................................... .1 A63H 33/04 [57] ABSTRACT [55] Clf' """"""""""""""" "5“"3'44364/ 27121}:66/ 24% Sets of educational blocks are described wherein special [5 1 leld 0 search?gk'igg'i'gg 155/711’ 4134 volumetric relationships are combined with visually ’ ’ ’ ’ distinctive geometric shapes. In one set of blocks a [56] References Cited common cube is cut into distinctive segments along a U5 PATENT DOCUMENTS single slice to form particular polygons. In another set 2 843 97‘ 7/1958 G d n 35/72 X of blocks a common cube is cut in a manner to provide ’ ’ ar, C In .......................... 1, polyhedra of distinctive‘ ' ' appearance with' related outer 1659360 5/1972 Zelschegg """"""""""""""" “ 35/72 segments used to ?ll out the common cube. Particular FOREIGN PATENT DOCUMENTS volumetric relationships between the polyhedra and 1064191 12/1953 France .............................. ., 273/293 their “med segments are described' 1316018 12/1962 France 35/72 2338064 8/1977 France .............................. ., 273/146 3 Claims, 29 Drawing Figures US. Pawn Mar. 2, 1982 Sheet 1 of? 4,317,654 PAW/u 4 £4 OGEAIM A’l/omso’s 5L ICE U8, Patsnt Mar. 2, 1982 Sheet 2 of? 43179654 574/’? 5 52 US“ Patsnt Mar. 2, 1982 Sheet 3 of7 4,317,654 52 / g KEITH/V6111”)? TR/SECTED CUBE US“ Patsm Mar. 2, 1982 Sheat 4 0f 7 43179654 iZ W1 B/SECTED TETRRHEDRON US° Patet Mar. 2, 1982 Sheet 5 of"? 49311654 4,317,654 1 2 correspondences which are selected to enhance an un EDUCATIONAL BLOCKS derstanding of various geometric relationships. These and other objects of the invention can be un This is a division of application Ser. No. 896.175, ?led derstood from the following description of sets of edu Apr. 14, 1978, now abandoned. cational blocks in accordance with the invention and described with reference to the following drawings. FIELD or THE INVENTION‘ BRIEF DESCRIPTION OF DRAWINGS This invention relates to educational blocks generally and to sets of educational blocks having particular FIG. 1 is a perspective view of a common cube with shapes and volumetric relationships for the visualization a single slice at an angle selected to form an equilateral and manipulation of interrelationships. parallelogram or rhombus face; FIG. 2 is a perspective exploded view of the sliced BACKGROUND OF THE INVENTION segments of FIG. 1; Blocks having speci?c interrelationships are well FIG. 3 is a perspective view of a common cube with known and have been described for educational uses. 5 a single slice at an angle selected to form a regular See, for example, the US. Pat. No. 3,208,162 to Wisdom hexagon face; wherein a square and cube root demonstrator is de FIG. 4 is a perspective exploded view of the sliced scribed. The U.S. Pat. No. 595,782 teaches a block segments of FIG. 3; model wherein a unit cube is divided into particular F IG. 5 is a perspective view of a common cube with volumetric fractions such as a third, two thirds and the 20 a single slice at an angle selected to form a pentagon like. Several trigometric relations can be illustrated face; with the blocks. The block construction described by FIG. 6 is a perspective exploded view of the sliced Randolph in 11.5. Pat. No. 3,645,535 describes various segments of FIG. 5; relationships between a tetrahedron, cube, and an octa FIG. 7 is a perspective view of a common cube with hedron and adapting these in a block system. Various 25 a single slice at an angle selected to form a trapezoidal polyhedra are shown in a publication by Coxeter enti face; tled “Introduction to Geometry”, published by Wiley FIG. 8 is a perspective exploded view of the sliced and Sons, and in a book entitled “Shapes, Space and segments of FIG. '7; Symmetry” by A. Holden, published by Columbia Uni FIG. 9 is a perspective view of a common cube with versity Press in 1971. a single slice at an angle selected to form a rectangular face; , SUMMARY OF THE INVENTION FIG. 10 is a perspective exploded view of the sliced With a set of educational blocks in accordance with segments of FIG. 9; the invention, the volumetric interrelationship of blocks FIG. 11 is a perspective exploded view of segments formed from a common cube is provided with segments 35 of a common cube having a single slice at an angle of particular volume. This technique enhances an un selected to form a triangular face; derstanding of the volumes involved in complex solids FIG. 12 is a perspective view of a common cube cut by assembling outer pieces to form a common cube. into three equal triad pentahedron segments along cubic Visualization of a complex solid encased in a common diagonal lines; cube reveals the kinds of symmetries which may be FIG. 13 is a perspective exploded view of the triad involved. segments of FIG. 12; As described with reference to one embodiment for a FIG. 14 is a perspective view of a common cube cut set of blocks in accordance with the invention, a plural into four segments including a regular tetrahedron and ity of segments are cut from a common cube with a three pyramidal outer tetrahedrons; single slice. Various face shapes are obtained, depend 45 FIG. 15 is a perspective exploded view of the four ing upon the direction of the slice. Thus, a triangle, a segments shown in combined form in FIG. 14; rectangle, rhombus, pentagon, parallelogram and hexa FIG. 16 is a perspective view of a trisected regular gon are illustrated with the sliced segments. A further tetrahedron as shown in FIG. 15; interrelationship involves the selective sizing of the FIG. 17 is a perspective exploded view of the trisec segments to provide a unique volumetric relationship 50 tional segments of the tetrahedron as shown in FIG. 16; which can be conveniently illustrated with a balance. FIG. 18 is a perspective view of an assembled bi In another form of a set of educational blocks in ac sected regular tetrahedron as shown in FIG. 15; cordance with the invention, well known polyhedra FIG. 19 is a perspective exploded view of the bi block forms are embedded in a common cube. These are sected segments of the tetrahedron as shown in FIG. 18; special polyhedra or sections thereof of regular or semi 55 FIG. 20 is a perspective view of a common cube cut regular shapes such as the tetrahedron, octahedron, into a plurality of septahedrons which combine with a rhombic dodecahedron, pentahedron, and orthotet regular rhombic dodecahedron to form the common rakaidecahedron. These polyhedra are provided with cube; complementary segments which respectively combine FIG. 21 is a perspective of the common cube as to form a common cube. Speci?c volumetric relations shown in FIG. 20 with one of the septahedron segments between the block segments illustrate the unique rela removed; tionships of the blocks to each other. FIG. 22 is a perspective exploded view of the seg These sets of educational blocks may be in solid form ments of the common cube shown in FIG. 20; or in die cut form to be subsequently erected. FIGS. 23 and 24 are perspective views of an assem It is, therefore, an object of the invention to provide 65 bled common cube cut into a regular octahedron and sets of educational blocks for illustrating geometric outer octahedron segments; interrelationships. It is a further object of the invention FIG. 25 is an exploded view of the segments of the to provide a set of educational blocks with volumetric common cube shown in FIG. 23; 4,317,654 3 4 FIGS. 26 and 27 are perspective views of an assem three dimensional relationships between planar ?gures bled common cube cut into an orthotetrakaidecahedron and solids. and complementary hexagon faced corner forming sep FIGS. 12-29 show a plurality of common cube form tahedra; - ing blocks which can be used to provide a set of blocks FIG. 28 is a perspective view of the orthotet of distinctive intricate polyhedra. The set of polyhedra rakaidecahedron ‘shown in FIG. 27; and blocks is so formed by selecting at least several common FIG. 29 is a‘ perspective viewof the corner forming cube forming blocks from the group of blocks illus septahedron shown in FIGS. 26 and 27. trated in FIGS. 12-29. In FIGS. 12 and 13 a common cube 50 is shown cut DESCRIPTION OF EMBODIMENTS into a triad of equal sized diagonal pentahedrons 90, FIGS. 1 through 11 show a variety of common cube each of which has a common diagonal 92 formed be forming blocks which‘can be used to provide a set of tween opposite corners 66'—66" of the cube 50. Each educational blocks. The set of blocks is formed by se diagonal pentahedron is one third of the volume of the lecting at least several common cube forming blocks common cube 50.
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