Abstract:
An amusement device concerned generally with a construction type educational toy. The amusement device provides unique functionality via board design and piece structure allowing relative motion between coupled playing pieces. The construction apparatus is of the type having rotary path-forming pieces that can be located in numerous positions on the base board. The pieces are removably interfitting and allow the construction of variable paths and patterns. The amusement device incorporates magnetism to perform relative rotary motion. A circular pattern of permanent magnets are included in construction pieces to allow numerous magnetically coupled rotary pieces to undergo relative rotation analogous to a gear train. In addition to toy or game amusement device, the present invention also embodies an education and demonstration device whereby the assembly of magnetically coupled rotary pieces provides the interactive demonstration of a gear train machine mechanism.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority of U.S. Provisional Patent Application No. 61/033,722 filed 04 Mar. 2008, of U.S. Provisional Patent Application No. 61/041,831 filed 02 Apr. 2008, of U.S. Provisional Patent Application No. 61/146,793 filed 23 Jan. 2009, and each of which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is an amusement device concerned generally with a construction type educational toy. The apparatus disclosed provides unique functionality via board design and piece structure allowing relative motion between coupled playing pieces. The construction apparatus is of the type having rotary path-forming pieces that can be located in numerous positions on the base board. The pieces are removably interfitting and allow the construction of variable paths and patterns. 
         [0003]    The amusement device incorporates magnetism to perform relative rotary motion. A circular pattern of permanent magnets are included in construction pieces to allow numerous magnetically coupled rotary pieces to undergo relative rotation analogous to a gear train. In addition to toy or game amusement device, the present invention also embodies an education and demonstration device whereby the assembly of magnetically coupled rotary pieces provides the interactive demonstration of a gear train machine mechanism. 
       BACKGROUND OF THE INVENTION 
       [0004]    A variety of amusement devices exist having parts assembled for relative movement including rotary gears, pulleys, or strand-winding members such as those found in United States Patent Class 446, Subclass 112 and having permanent magnets in United States Patent Class 446, Subclass 129. Likewise, other amusement devices exist as games in United States Patent Class 273 including, but not limited to, Subclasses 239, 275, 276, 282.1, 284, 287, and 288. Still further, a variety of related machine mechanisms exist for education and demonstration having means for demonstrating apparatus, product, or surface configuration, or for displaying education material or student&#39;s work such as those found in United States Patent Class 434, Subclass 401. 
       SUMMARY OF THE INVENTION 
       [0005]    It is an object of the present invention to obviate or mitigate at least one disadvantage of previous amusement devices. 
         [0006]    In a first aspect, the present invention provides a construction set including: a plurality of magnetized rotary construction pieces and a journal board adapted for receiving the magnetized rotary construction pieces within a playing area of numerous closely-spaced receptacle pivot locations; the magnetized rotary construction pieces each including a body portion and a centralized axle projection; the axle projection adapted to removably-fit on the journal board and rotate within the receptacle pivot locations of the journal board; the body portion further including magnetized elements arranged in a circular pattern with numerous locations of outward magnetic polarity around the periphery of the rotary construction pieces; and magnetized elements adapted for providing for rotational magnetic coupling when the magnetized rotary construction pieces are placed in proximity to each other on the journal board. 
         [0007]    In further aspect, the present invention provides a construction set including; a magnetized drive ring, a plurality of magnetized rotary construction pieces and a journal board including a journal array adapted for receiving the magnetized rotary construction pieces within a playing area of numerous receptacle pivot locations; the journal board further including a substantially annular ring supporting means adapted for providing the pivoting of the magnetized drive ring around the periphery of the journal hole array; the magnetized rotary construction pieces each including a body portion and a centralized axle; the axle adapted to removably-fit on the journal board and rotate within the receptacle pivot locations of the journal board; the body portion further including a circular pattern of magnetized elements adapted for rotational magnetic coupling when the magnetized rotary construction pieces are closely spaced apart on the journal board; the magnetized drive ring including a ring-shaped body characterized by a major and minor diameter and a rotation drive means; the magnetized drive ring adapted to be rotationally supported by the annular ring supporting means of the journal board; and the ring-shaped body including a circular pattern of magnetized elements positioned near the minor diameter and adapted to provide rotational magnetic coupling when the magnetized rotary construction pieces are placed on the journal board within the magnetized drive ring in proximity to the minor diameter of the magnetized drive ring. 
         [0008]    Generally speaking, the present invention is an amusement device concerned with a construction toy system of high educational value. The construction type apparatus disclosed provides unique capability for amusement via board design and playing piece structure allowing relative motion between playing pieces. The apparatus is of the type having rotary path-forming playing pieces that can be located in numerous positions on a journal board. Moreover, the playing pieces are removably interfitting and allow the construction of variable paths and design patterns. 
         [0009]    The amusement device incorporates magnetism to perform relative rotary motion. A circular pattern of permanent magnets are included in playing pieces to allow numerous magnetically coupled rotary pieces to undergo relative rotation analogous to a gear train. 
         [0010]    The invention has multiple formats and applications. A preferred format is a construction system in which a person can employ the playing pieces in numerous patterns and configurations for achieving complete magnetic coupling and simultaneous motion. 
         [0011]    An individual may explore numbers patterns and configurations of magnetically coupled rotary playing pieces as curiosity directs in “solitare” play. As playing pieces are removably interfitting with the game board, the rotating disks can be arranged and re-arranged with substantial freedom to form theories and investigate results of pattern formation. For example the device allows the construction of circular patterns, linear patterns, spiral patterns, and patterns which are symmetrical about one or more planes. Depending on placement and configuration the invention allows an individual to also form closed loops where as more than one playing piece of the same “gear train” is linked to the lead gear. 
         [0012]    As the invention allows simultaneous motion of a multitude of disks, dynamic visual results can be achieved with greater expression through the deployment of graphical cover plates. These covers can be added and exchanged based on the user&#39;s opinion. The plastic cover plates add an extra layer of creative construction and play since the interchanging graphics can give a single pattern a different look and feel and thus a higher level of versatility and personalization is enjoyed in the contest of the construction system. 
         [0013]    According to a secondary format, the construction system can be adapted for competitive playing by a number of individuals. In competitive play, players take turns adding rotary playing piece until free space on the board is diminished to the point where adding additional pieces disrupts the magnetic coupling of previously placed rotary pieces. According to this competitive format, the path forming game of this type relies on mental processes and strategy to construct a pattern in maximizing the number of magnetically coupled rotary playing pieces as part of the “gear train”. 
         [0014]    In all conceived playing formats, successful execution will depend on mental process such as knowledge of combinations relative to interchangeable gears and being able to visually estimate transverse and diagonal distances between placement locations. Successful placement also depends on an awareness on how distance between playing pieces relates to the magnitude of constructive coupling or interference depending on the properties of the playing pieces such as size and pattern of permanent magnets displaced on rotary playing pieces. 
         [0015]    Competitive game play according to the present invention does also enable the use of strategy for proactive placement or rotary playing pieces in the attempt to limit the selection of pivot locations of an opposing opponent and force the outcome of an opponent causing the “gear train” to “lock up” on account of poor placement or limited placement options. Thus it will be come apparent to one skilled in the art that the novel construction system provides an interactive apparatus for exploring the principles of magnetic coupling and relative motion. Such an interactive apparatus is so adapted to be both enjoyable and intellectually stimulating. 
         [0016]    In addition providing amusement and various formats for play, the present invention also embodies an education and demonstration device whereby the assembly of magnetically coupled rotary pieces provides the interactive demonstration of a gear train machine mechanism 
         [0017]    The invention enables a high degree of interchangeable, variable, or plural distinct playing patterns via the substantially dense array of pivot locations provided for within the journal board array. The closely spaced array of receiving holes enables relatively precise positioning of playing pieces to build an assembly that exhibits relative movement of all magnetically coupled playing pieces via rotation of single driving disk or ring. 
         [0018]    Several embodiments are disclosed including a first preferred embodiment in a system designed around a journal board in which a driving disk shaped crank is centrally located. According to this embodiment, playing pieces are placed to extend the “gear train” of magnetically coupled rotary playing pieces such as to provide an “inside-out” playing format. 
         [0019]    Other preferred embodiments include those wherein the journal board is circular and a rotational-magnetic ring crank is located to revolve around the outside of the array of journal positions. According to this preferred embodiment, playing pieces are added to extend the “gear train” from the inside of the ring toward the center of the journal hole array such as to provide an “outside-in” playing format. The exterior ring crank comprises a revolving handle which allows easy revolution according to the manipulation of the user. 
         [0020]    An added benefit of this preferred configuration, in comparison to other configurations utilizing a central driving gear is that the players can drive the rotary playing pieces to spin at higher speeds enabling them to explore a wider range of visual and magnetic interactive effects with greater ability to alter the dynamics. For example, relative motion between rotary playing pieces caused by magnetic coupling can be overcome by suddenly switching the direction of rotation and rotating at high speed. One or more playing pieces that would normally spin when rotating the driving member at low speed can be caused not to spin at high speed by dynamic manipulation. Furthermore, a player can strategize about the placement of rotary playing pieces such that intended dynamic effects can be deliberately achieved. 
         [0021]    To summarize, the construction system according to the present invention is characterized with the following advantages. 
         [0022]    The construction system is fun and enjoyable to play and use. 
         [0023]    The construction system is intriguing in that it allows a large number of non-touching rotary playing pieces to be magnetically coupled so as rotation of one rotary playing piece causes a great many of other playing pieces to also rotate. 
         [0024]    The construction system is highly interactive and allows many variable paths and patterns. 
         [0025]    The construction system is visually pleasing and allows one to see the effects of applying customizable graphics to simultaneously spinning playing pieces. 
         [0026]    The construction system instructs players of the principles of magnetic coupling and interaction and how variables act to encourage and discourage the rotational coupling. 
         [0027]    The construction system instructs players of relative rotary motion analogous to gear trains. 
         [0028]    The construction system encourages spatial intelligence in the strategic placement of rotary playing pieces. 
         [0029]    The amusement device provides a novel format of play whereas magnetic properties of rotary playing pieces work both productively and counter-productively in the progress of play. 
         [0030]    The construction system allows an individual to explore and investigate numerous patterns and configurations as curiosity leads. 
         [0031]    The construction system is novel and intriguing in how it allows one to visualize magnetic interaction in a dynamic format. 
         [0032]    The construction system is “hands on” in that one can touch and feel the results of configuring and reconfiguring the magnetically coupled apparatus. 
         [0033]    Other advantages and benefits may be possible, and it is not necessary to achieve all or any of these benefits or advantages in order to practice the invention as claimed. Therefore, nothing in the forgoing description of the possible or exemplary advantages and benefits can or should be taken as limiting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]    The novel features of the present invention, which are considered as characteristic for the invention, are set forth with particularity in the appended claims. The invention itself, however, both as to organization and methods of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings in which: 
           [0035]      FIG. 1  is a perspective view of a journal board with a set of magnetically coupled rotary pieces according to a first preferred embodiment of the present invention. 
           [0036]      FIGS. 2A-2C  are top, perspective, and side views of a small magnetic playing piece and complementary face plate according to preferred embodiments of the present invention. 
           [0037]      FIG. 2D  is a sectional view of the rotational-magnetic playing piece of  FIGS. 2A-2C  taken along the section line of  FIG. 2A . 
           [0038]      FIG. 2E  is a sectional view of the rotational-magnetic playing piece of  FIGS. 2A-2D  taken along the section line of  FIG. 2C . 
           [0039]      FIGS. 3A-3C  are top, perspective, and side views of a large rotational-magnetic playing piece and complementary face plate according to preferred embodiments of the present invention. 
           [0040]      FIG. 3D  is a sectional view of the rotational-magnetic playing piece of  FIGS. 3A-3C  taken along the section line of  FIG. 3A . 
           [0041]      FIG. 3E  is a sectional view of the rotational-magnetic playing piece of  FIGS. 3A-3D  taken along the section line of  FIG. 3C . 
           [0042]      FIGS. 4A-4C  are top, perspective, and side views of a rotational-magnetic driving crank according to preferred embodiments of the present invention. 
           [0043]      FIG. 4D  is a sectional view of the rotational-magnetic driving crank of  FIGS. 4A-4C  taken along the section line of  FIG. 4A . 
           [0044]      FIG. 4E  is a sectional view of the rotational-magnetic driving crank of  FIGS. 4A-4D  taken along the section line of  FIG. 4C . 
           [0045]      FIGS. 5A-5B  are top and side views of a small rotational-magnetic playing piece magnetically coupled to a rotational-magnetic drive crank according to preferred embodiments of the present invention. 
           [0046]      FIG. 5C  shows the coupled rotational-magnetic small playing piece and drive crank of  FIGS. 5A-5B  along the section line of  FIG. 5B . 
           [0047]      FIGS. 6A-6B  are top and side views respectively of the journal board with magnetically coupled rotary pieces according to the first preferred embodiment of a construction set according to the present invention wherein various sized rotational-magnetic playing pieces are arranged in a line along the middle of a journal base board in a configuration enabling rotational magnetic coupling. 
           [0048]      FIG. 6C  is a sectional view of the configured first preferred embodiment of  FIGS. 6A-6B  taken along the section line of  FIG. 6A . 
           [0049]      FIG. 6D  is a sectional view of the configured first preferred embodiment of  FIGS. 6A-6B  taken along the section line of  FIG. 6B . 
           [0050]      FIG. 7  is a perspective view of a second preferred embodiment of a configured construction set according to the present invention utilizing an octagon shaped journal base board wherein the rotational-magnetic drive crank is centrally located and rotational-magnetic playing pieces are arranged in a substantially symmetrical pattern. 
           [0051]      FIG. 8A-8B  are top and side views of a second preferred embodiment of an octagon shaped journal base-board wherein numerous rotational-magnetic playing pieces are arranged in a unique spread apart circular pattern and wherein rotational-magnetic playing piece are configured with differing face plates as compared to the configuration of  FIG. 7 . 
           [0052]      FIG. 9A  is a perspective view of a third preferred embodiment of a configured construction set according to the present invention utilizing a circular shaped journal base board adapted to receive a ring shaped rotational-magnetic drive crank wherein rotational-magnetic playing pieces are placed within the interior of the ring shaped rotational-magnetic drive crank in a somewhat random configuration. 
           [0053]      FIGS. 9B and 9C  are exploded and non-exploded perspective views of the third preferred embodiment and configuration shown in  FIG. 9A . 
           [0054]      FIGS. 10A-10C  show perspective, top and side views respectively of a second rotational-magnetic playing piece configuration according to the third preferred embodiment of the present invention utilizing a ring shaped rotational-magnetic drive crank wherein the rotational-magnetic playing piece are arranged in a symmetrical cross pattern. 
           [0055]      FIG. 10D  shows a sectional view of the preferred embodiment and configuration of  FIGS. 10A-10C  taken along the section line of  FIG. 10B . 
           [0056]      FIG. 10E  shows a sectional view of the preferred embodiment and configuration of  FIGS. 10A-10D  taken along the section line of  FIG. 10C . 
           [0057]      FIG. 11A-11H  shows several preferred graphical embodiments of large, medium and small face plates according to the present invention. 
           [0058]      FIG. 12A-12B  shows a side view and sectional view of a small rotational-magnetic playing piece magnetically coupled to a rotational-magnetic drive crank according to an alternative embodiment of the present invention. The section view of  FIG. 12B  is taken along the section line of  FIG. 12A . 
       
    
    
     DETAILED DESCRIPTION 
       [0059]    As utilized herein, terms such as “about”, “approximately”, “substantially” and “near” are intended to allow some leeway in mathematical exactness to account for tolerances that are acceptable in the trade. 
         [0060]    Before explaining the present invention in detail, it should be noted that the invention is not limited in its application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative embodiments of the invention may be implemented or incorporated in other embodiment, variations and modifications, and may be practices or carried out in various ways. Furthermore, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative embodiments of the present invention for the convenience of the reader and are not for the purpose of limiting the invention. Further it is understood that any one or more of the following-described embodiments, expressions of embodiments, examples, methods, etc. Can be combined with any one or more of the other following-described embodiments, expressions or embodiments, examples, methods, etc. 
         [0061]    Referring to  FIGS. 1-6E , a first preferred embodiment of the present invention is shown. 
         [0062]      FIG. 1  is a front perspective view of a construction set according to the first preferred embodiment. The construction set includes journal base board  110 , rotational-magnetic disk crank  74 , and a group of rotary playing pieces  61  comprising several large rotational-magnetic playing pieces  62 A, medium rotational-magnetic playing pieces  62 B, and small rotational-magnetic playing pieces  62 C. Playing pieces  62 A, B and C are each provided with graphical face plates  80 E,  81 E, and  82 E respectively. 
         [0063]    The base of the apparatus is journal board  110  adapted to receive rotational-magnetic playing pieces  61 . Each large, medium and small rotational-magnetic playing pieces  62 A,  62 B, and  62 C comprises a substantially circular disk body  64 A, B and C. Handle portion  65 A, B and C is a slender projection extend above respective disk bodies for facilitating hand placement on journal base board. Each of the rotational-magnetic playing pieces further comprise shafts portion  66 A, B and C respectively centrally projecting below disk bodies  64 A, B, and C and are adapted to closely fit within variable journal positions of journal hole array  112  of journal board  110 . 
         [0064]    Playing pieces are further provided with graphical cover plates  80 E,  81 E, and  82 E adapted to fit on magnetic-rotational playing pieces over handle portions  65 A,  65 B and  65 C respectively. 
         [0065]    Journal board  110  comprises journal grid  112  which is an array of holes of sufficient depth to receive shaft portions  66 A, B and C of rotational-magnetic playing pieces  62 A, B and C. Accordingly, playing pieces  62 A, B, and C slip into journal board  110  and are permitted to pivot in numerous pivot locations as provided by journal hole array  112  having a grid comprising a hole pattern. Journal hole array  112  is of sufficient size and hole density to allow numerous pivot locations for rotational-magnetic playing piece  62 A, B, and C to be placed in close proximity on journal board  110  such that disk portions  64 A, B, and C reside on top surface  114  of journal board  110  without touching each other while also freely pivoting on axis of each respective shaft portion  66 A, B, and C. Preferably journal board  110  is made of a low friction plastic material such as Acetal copolymer or PVDF. Another preferred low friction yet dimensionally stable material would be Delrin impregnated with Teflon. 
         [0066]    Holes of journal hole array is preferably of maximum area and density for allowing the maximum number of pivot locations within area of journal hole array  112 . Accordingly, the preferred spacing between holes is less than 1.5 times the hole diameters. Journal base board  110  is of sufficient thickness to support rotational-magnetic playing piece in magnetically coupled configurations without yielding under the action of magnetically attractive and repulsive forces. 
         [0067]    Rotational-magnetic disk crank  74  is provided with revolving handle  75  projecting from the top of disk portion  64  and located near the edge of disk portion  64  for enabling crank operation in initiating rotation of magnetically coupled rotational-magnetic playing pieces  64 A, B and C. Preferably, rotational-magnetic disk crank comprises disk portion  64  of larger size than rotational-magnetic playing pieces  61 , whereas the larger size helps facilitate the cranking action and enables a larger number of rotational-magnetic playing pieces to be magnetically coupled directly to disk crank  74 . 
         [0068]    Shown in  FIG. 1 , one of each large, medium, and small rotational-magnetic playing pieces  62 A, B, and C are configured in a spaced apart row along side rotational-magnetic drive crank  74 . According to this configuration, rotation drive crank  74  will cause magnetically coupled rotational-magnetic playing pieces  62 A, B, and C to rotate with direction of spin alternating from playing piece to playing piece. 
         [0069]    Now referring to  FIGS. 2A-2E , the preferred construction of small rotational-magnetic playing piece  62 C is shown in greater detail along with complementary graphical cover plate  82 E. As shown, the small rotational-magnetic playing piece  62 C of this preferred embodiment comprises circular disk body  64 C having central handle portion  65 C projecting above and central shaft portion  66 C projecting below. 
         [0070]    Shaft portion  66 C and handle portion  65 C are integral to disk body  64 C where as they are all part of a single injection molded component to which rectangular magnets are subsequently installed. Although shaft portion is of a small diameter the required length is sufficiently small to prevent it from being easily damaged a result of applied bending loads. This provides a cost advantage with the ability to mass produce the rotational-magnetic playing pieces with minimum additional material costs other than the costs of the embedded rectangular magnets  69 . Alternatively the shaft portion  66 C may consist of a metal pin pressed into disk portion  64 C. Such a shaft could provide reduced friction and increased stiffness to shaft portion  66 C. Above shaft portion  66 C disk portion  64 C further comprises contoured bottom  71 C for reducing the contacting surface area with the journal base board  110  when placed thereon whereas the surface area of bearing surface  72 C is much less than the surface area corresponding to contoured bottom  71 C. 
         [0071]    Disk body  64 C further comprises axial slots  68 C in which rectangular magnets  69  are housed. Axial slots  68 C are arranged in a circular pattern within disk body  64 C for accommodating rectangular magnets  69  in a circular pattern near disk parameter  74 C. When pressed into axial slots  68 C, rectangular magnets  69  are substantially embedded in disk body. Slot recesses  70 C remain when the rectangular magnets are fully inserted during manufacturing and can be subsequently filled with adhesive or an interlocking cap so that magnets  69  are completely encapsulated within disk body  64 C. However a light interference fit is all that is needed for preventing rectangular magnets  69  from being able to be dislodged from disk body  64 C when under magnetic attractive and repulsive loading. Alternatively, rectangular magnets  69  are over molded during manufacturing to provide full encapsulation. 
         [0072]    As shown in the sectional view of  FIG. 2E , disk body  64 C comprises an even number of axial slots  68 C for accommodating an even number of rectangular magnets  69  which are arranged as to exhibit a radial outward polarity of which north and south poles alternate. Small rotational-magnetic playing piece  62 C comprises  10  rectangular magnets  69  closely spaced around the inside of the disk parameter  73 C. 
         [0073]    According to this preferred embodiment, centralized handle portion  65 C is substantially slender, is sufficiently long to be gripped by hand for easy placement, and is of an oblong cross section. The slenderness of handle portion  65 C enables graphical cover plate  82 E to be of maximum surface area and the oblong shape facilitates interlocking with central oblong hole  83 C of cover piece  82 E so that when cover plate  82 E is placed on rotational-magnetic playing piece  62 C it spins in conjunction with small rotational-magnetic playing piece  62 C. 
         [0074]    Small graphical cover plate  82 E is preferably a removable substrate that can be placed upon rotational-magnetic playing piece  62 C or can be exchanged for graphical cover plates of the same size having alternate graphics. For example Small graphical cover plate  85 E could be a stamped from a plastic sheet and provided with an adhesive graphics. Alternatively graphical cover plate  82 E may comprise a substrate suitable for painted or printed graphics applied directly thereto. Another alternative is for graphical cover plate to a cardboard cutout supplied with the construction set whereas differing supplied cardboard graphical cover plates can be selected from punch-out cardboard sheets of profiles and graphical indication means similar to the various graphical cover plates shown in  FIGS. 11A-11E . 
         [0075]    Graphical cover plate  82 E is characterized as a thin disk with outside diameter  84 C and a central oblong hole  83 C. Outside diameter  84 C is substantially equivalent to diameter associated with disk parameter  73 C. Graphics  89 E are displaced on top face  85 C and optionally also on bottom face  86 C. For example, a clockwise spiral graphic similar to that shown may be on the top face while the bottom face may contain a counter-clockwise spiral so that playing pieces may be configured so that you get the same dynamic visual effect for playing pieces rotating both clockwise and counterclockwise. 
         [0076]    Now referring to  FIGS. 3A-3E , the preferred construction of large rotational-magnetic playing piece  62 A is shown in greater detail along with complementary graphical cover plate  80 E. As shown, the large rotational-magnetic playing piece  62 A of this preferred embodiment comprises circular disk body  64 A with central handle portion  65 A projecting above and central shaft portion  66 A projecting below. In like manner to small rotational-magnetic playing piece  62 C of  FIGS. 2A-2E  disk body  64 A comprises contoured bottom  71 A, bearing surface  72 A, and axial slots  68 A for accommodating rectangular magnets  69 . However disk body  64 A of large rotational-magnetic playing piece  62 A is characterized with a disk parameter  73 A significantly larger than that of small playing piece  62 C of  FIGS. 2A-2E  and is configured with a larger number of axial slots  68 A to receive a larger number of rectangular magnets  69  arranged in a circular pattern of alternating radial north and south poles. In this case, disk body  64 A houses sixteen rectangular magnets as compared to ten rectangular magnets embedded in disk body  64 C of small rotational-magnetic playing piece  62 C. 
         [0077]    Also similar to small rotational-magnetic playing piece  62 C, centralized handle portion  65 A is substantially slender and of an oblong cross-section. This enables graphical cover plate  80 E to be of maximum surface area and the oblong shape facilitates interlocking with central oblong hole  83 A of cover piece  80 E so that, when cover plate  80 E is placed on rotational-magnetic playing piece  62 A, it spins in conjunction with large rotational-magnetic playing piece  62 A. 
         [0078]    Now referring to  FIGS. 4A-4E , the preferred construction of rotational-magnetic disk crank  74  is shown in greater detail. Unlike rotational-magnetic playing pieces  62 A, B and C, rotational-magnetic disk crank  74  does not comprise a central slender handle portion and is not provided with a complementary removable cover plate. Rather disk portion  64  of rotational-magnetic disk crank comprises an affixed revolving handle  75  projecting up along the side of disk portion  64  near disk parameter  73 . Preferably rotational-magnetic disk crank  74  is of larger size than rotational-magnetic playing piece  62 A, B and C and revolving handle  75  is of maximum offset with respect to centralized shaft portion  66  for facilitating convenient hand operation in driving rotational-magnetic disk crank  74 . 
         [0079]    Revolving handle  75  comprises handle base  76  affixed to disk body  64 . Handle sleeve  78  is retained on outside of handle base  76  and is adapted to freely rotate thereon so that a person may freely apply a cranking action to rotational-magnetic disk crank  74  whereas magnetic interaction between rotary playing pieces and inertia of playing pieces are the significant counteracting forces when initiating rotation of playing pieces. 
         [0080]    Rotational-magnetic disk crank  74  further comprises contoured bottom  71  for providing a bearing surface  72  of minimal yet adequate surface area for contacting journal board when shaft portion  66  is inserted into a pivot location within journal array  112 . 
         [0081]    Graphical indication means is located on top surface  67  of disk body  64  and preferably includes visual indication means to indicate polarity of internal rectangular magnets embedded within. Preferably graphical indication is provided by an adhesive decal or is printed directly on the substrate that comprises disk portion  64 . 
         [0082]    Similar to the preferred embodiment of playing pieces  62 A, B, and C, disk portion  64  of rotational-magnetic disk crank  74  comprises axial slots  68  for embedding rectangular magnets  69 . Preferably, subsequent to insertion of rectangular magnets  69 , the slot recesses  70  would be filled with adhesive or sealed in some other manner known to those skilled in the art. 
         [0083]    As shown in  FIG. 4E , rotational-magnetic disk crank  74  comprises an even number of rectangular magnets  69  housed in a circular pattern of axial slots  68  which is larger in number than large medium and small rotational-magnetic playing piece  62 A, B, and C. According to this preferred embodiment rotational-magnetic disk crank  74  comprises twenty rectangular magnets  69  of alternating radial polarity arranged near disk parameter  73 . 
         [0084]    It should be understood that the rotary playing pieces may be injection molded parts adapted to receive rectangular magnets  69 . Preferably, strong rare earth NdFeB permanent magnets are utilized which are composed mainly of Neodymium (Nd), Iron (Fe) and Boron (B). Although parameters  73 A, B, and C are shown as round the actual shape of disk body  64 A, B and C may be a polygon or another non-circular shape within the scope of the invention. Moreover, the magnets may be other than the rectangular magnets  69  as shown. 
         [0085]    Although according the preferred embodiment shown magnetized elements are discrete magnets (i.e., rectangular magnets  69 ) displaced in axial slots in circular configuration arranged to provide alternating outward polarity, it should be readily understood as within the scope of the invention that magnetization can alternatively be provided by magnetic strip wrapped around the parameter of disk bodies adapted for providing substantially equivalent functionality. It is know to those practiced in the art that multi-pole magnetic strip can be manufactured with a specified width, thickness and length whereas the magnetic strip exhibits a fixed number evenly distributed number of magnetic poles per unit length. For example, according to the invention, magnetic strip that is 0.100 inch thick, 0.250 inch wide and has four poles per inch can be utilized for providing substantially equivalent performance. 
         [0086]    Although magnetized elements according to an embodiment utilizing magnetic strip might require a greater volume of magnetic material to provide an equivalent magnetic field whereas a greater width or thickness as compared as to discrete magnets would be required, magnetic strip would provide a cost savings to the extent that cost attributed to magnetic strip as the magnetized elements would be ⅕ to 1/10 the associated costs of using discrete magnets. 
         [0087]    In addition to cost savings pertaining to the magnetic material, magnetic strip would also provide improved manufacturability of the device components as compared to utilizing costly discrete magnets which much be precisely accommodated within slots in disk bodies. According to an alternative embodiment utilizing magnetic strip as the magnetization means, the strip can be wrapped around and secured to disk bodies with the use of adhesive and preferably with additional means of securing the strip such as providing for a two-part disk body having a plug and socket type interface for fully encasing the magnetic strip. Such a configuration would likely be characterized with increased product safety. 
         [0088]    Referring to  FIGS. 5A-5B , rotational-magnetic disk crank  74  is show in proximity to small rotational-magnetic playing piece  62 C as if they were placed on a journal base board according to the present invention. As is typical with placement on a journal base board these figures show rotational-magnetic disk crank  74  and small rotational-magnetic playing piece  62 C are aligned in a manner whereas shaft portion  72  and  72 C are parallel and bearing surfaces  72  and  72 C coincident to the same plane. 
         [0089]    Referring to  FIG. 5C , a section view is shown along a line through disk bodies  64  and  64 C of rotational-magnetic disk crank  74  and small rotational-magnetic playing piece  62 C respectively. When placed in proximity on a journal board, rotational-magnetic disk crank  74  and small rotational-magnetic playing piece  62 C are magnetically coupled so that alternating north and south poles provided by radial magnets  69  cause rotation of small rotational-magnetic playing piece  62 C when rotational-magnetic disk crank  74  is rotated. This is facilitated by both the attraction of unlike poles and the repulsion of like poles between proximally located disk bodies. 
         [0090]    Circular magnetic pitch P 74  of rotational-magnetic disk crank  74  and circular pitch P 62 C of rotational-magnetic playing piece  62 C are substantially equivalent according to the invention as needed for effective coupling between various sized playing pieces. Thus all rotational-magnetic construction pieces including disk crank  74  and large, medium and small rotational-magnetic construction pieces  62 A, B, and C have a substantially equivalent circular pitch for providing interchangeability whereas all rotational-magnetic construction pieces can be effectively coupled together. 
         [0091]    In this preferred embodiment, variables associated with magnetic coupling are pitch diameters D 74 D and D 62 D working depth Dw and pitch point P. Magnetic coupling allows these variables to change depending on proximity of one playing piece to another. This a principal advantage of the invention as compared to other rotational construction type systems relying on mechanical interlocking such as those involving toothed mechanical gears. 
         [0092]    According to the invention, Dw can be very small or very large and still provide magnetic coupling between rotational-magnetic disk crank  74  and rotational-magnetic playing piece  62 C. However as working depth Dw increases as a result of further apart spacing, the strength of magnetic coupling decreases. The maximum working depth Dw is also influenced by the proximity of other nearby rotational-magnetic playing pieces. This variable is important in constructing various configurations and patterns because proximity can encourage magnetic coupling or cause counter-productive interaction. Thus strategy and intuition is required for achieving relative motion of all rotary construction pieces together such that when rotational-magnetic disk crank is cranked all other rotational-magnetic playing piece  62 A, B and C also spin. 
         [0093]    Referring to  FIGS. 6A-6D , the first preferred embodiment of the present invention is illustrated whereas a row of rotational-magnetic playing piece  62 A, B and C along with rotational-magnetic disk crank  74  are placed on rectangular journal board  110  along a central row of journal hole array  112 . Bearing surfaces of respective rotational-magnetic playing piece rest on top surface  114  of journal board  110  so that all internal magnets are approximately held at the same elevation. Preferably, shaft portions  72 ,  72 A, B, and C of rotational-magnetic playing pieces do not extend beyond bottom surface  115  when placed within journal board  110 . Rubber feet  116  are provide under journal board  110  to apply grip to journal board when a player is actuating rotational-magnetic disk crank  74 . 
         [0094]    Although rotational-magnetic playing pieces do not physically touch each other when placed in proximity on journal board array  112  the invention utilizes magnetic coupling such that manual rotation of one rotational-magnetic disk crank  74  will cause all magnetically coupled playing pieces  62 A, B and C to rotate. Several parameters influence magnetic coupling and the ability to build a path of closely placed rotational-magnetic playing piece  62 A, B and C wherein all rotate in response to the manual rotation of a rotational-magnetic disk crank  74 . These parameters include but are not limited to differences in radial pitch and size and distance between placed playing pieces. 
         [0095]    As indicated by shading of graphical cover plates shown in  FIG. 6A  and the magnetic polarities indicated in the section views of  FIG. 6C and 6D , rotational-magnetic playing piece  62 A, B, and C are magnetically coupled to rotational-magnetic disk crank  74  in radial orientations wherein opposite poles are aligned at regions of adjacency. Rotational-magnetic playing pieces can be said to be meshed whereas both attractive and repulsive forces work in regions of proximity to ensure relative motion between magnetically coupled rotational playing pieces. Again magnetic coupling can be explained by attraction of proximal magnetic north and south poles and by repulsion of proximal magnetic north and north or magnetic south and south poles. 
         [0096]    Although shown in a straight line, numerous configurations of magnetically coupled rotary construction pieces are possible by strategic placement of playing pieces  62 A, B and C within journal hole array  112 . Although rotational-magnetic playing piece  62 A, B and C vary in size and number of radial magnets  69  each rotational-magnetic playing piece  62 A, B and C comprises a circular pattern of an even number of spaced apart rectangular magnets  69  that are characterized with a substantially equivalent radial spacing. Thus large rotational-magnetic playing piece  62 A, medium rotational-magnetic playing piece  62 B and small rotational-magnetic playing piece  62 C are each characterized with a radial pitch within an acceptable range to facilitate effective magnetic coupling. 
         [0097]    The size of each disk portion corresponding to the various sized rotational-magnetic playing pieces  62 A, B and C is preferably determined according to a numerical relationship corresponding to the spacing between pivot point locations along journal hole array  112 . For example, according to the preferred embodiment of  FIGS. 1-6D , diameters of small, medium, and large rotational-magnetic playing piece  62 C, B and A and rotational-magnetic disk crank  74  are approximately ⅞″, 1⅛″, 1⅜″, and 1⅝″ respectively whereas spacing between pivot locations of journal hole array  112  is ⅛″. This sizing and space relationship allows substantially precise placement of rotational-magnetic playing pieces in close proximity along a line. 
         [0098]    According to the invention, when journal hole array  112  is populated with rotational-magnetic playing piece  62 A, B and C, it becomes increasingly difficult to construct a fully rotating train of rotational-magnetic playing pieces  62 A, B and C, due to the unintended interference (counter-productive interaction) of previously placed rotational-magnetic playing pieces  62 A, B and C which acts to lock up portions of the path formed. As space becomes less available along journal hole array  112 , a player becomes more limited in availability of successful positions for productive placement of rotational-magnetic playing piece  62 A, B and C and it becomes more challenging to successfully extend the number of magnetically coupled playing pieces that rotate upon the manual rotation of rotational-magnetic disk crank  74 . 
         [0099]    A preferred format of play within the scope of the present invention is the ability to form patterns and form numerous variable paths of magnetically coupled rotating elements. Thus the objective of one or more players is to incrementally add rotary construction pieces to journal hole array that form a magnetically coupled path from rotational-magnetic disk crank  74  whereas rotation of rotational-magnetic ring crank will cause all placed rotary construction pieces to also rotate and experience relative motion. Such patterns can take on numbers shapes and depict things such as robots or other objects. Patterns may have various degrees of symmetry and may have triangular, rectangular or circular paths. 
         [0100]    An alternative format of play of the present invention is a construction type path-forming challenge to maximize the number of magnetically coupled rotary construction pieces that can be attached to the “gear train” before a lock up occurs that prevents one or more rotary construction pieces from rotating. According to this format, a multi-player game would instruct players to take turns adding rotary construction pieces. The player that causes magnetic lockup of one or more rotary playing through counter-productive placement of rotary construction pieces looses the game. Thus loss would be incurred either through poor placement strategy or a lack of placement options due to congestion of rotary construction pieces covering most of the journal board. Thus an enjoyable and intellectually demanding method of play is to maximize the number of rotary construction pieces added to the “gear train” before “lock-up” is encountered. 
         [0101]    Thus it will be come apparent to one skilled in the art that the present invention provides an interactive apparatus for exploring the principles of magnetic coupling and relative motion. Numerous other formats are also envisioned including the goal to produce specific patterns or to link a rotational-magnetic playing piece on one position on the journal board to one or more rotational-magnetic pieces at a distant spaced apart location. Such an interactive apparatus is so adapted to be both enjoyable and intellectually stimulating. 
         [0102]    Referring to  FIGS. 7-8B , a second preferred embodiment of a construction set according to present invention is shown wherein an octagon-shaped journal base board  120  is provided. Journal base board  120  comprises a larger surface area and increased number of pivot locations for enabling the formation of numerous patterns from extended paths of magnetically coupled playing pieces. Examples of such pattern of numerous large, medium and small rotational-magnetic playing pieces  62 A, B and C are shown in  FIG. 7  and in  FIGS. 8A-8B . 
         [0103]    Although not necessary to the embodiment, both configurations rely on centrally located rotational-magnetic disk crank  74  to initiate rotation of all magnetically coupled playing pieces. In addition to having differing patterns  FIG. 7  and  FIGS. 8A-8B  also show the application of differing graphical cover plates as facilitated by the invention whereas cover plates  80 ,  81 , and  82  are removable and differing graphical indication means can be exchanged. 
         [0104]    An interchangeable construction apparatus of this size is provided to facilitate play whereas a large number of rotational-magnetic playing pieces can be magnetically coupled for producing relative motion resultant from the hand rotation of a single drive crank. Numerous path formations and patterns can be constructed as journal hole array  122  is of sufficient size and density for adding a substantial number of rotational-magnetic playing piece providing extended play for making the construction device more enjoyable and captivating for the players. 
         [0105]    Referring to  FIGS. 9A-10E , a third preferred embodiment of the amusement construction apparatus according to present invention is shown whereas a circular journal board  30  is adapted to receive rotational-magnetic ring crank  89  for facilitating rotation of rotational-magnetic playing pieces  62 A, B, and C located within the interior along journal hole array  31 . Rotational-magnetic playing pieces  62 A, B and C are identical to the previous disclosed embodiments. As opposed to the previous embodiments of centralized rotational-magnetic disk crank  74  from which other rotational-magnetic playing piece are generally placed near the center of the journal hole array toward the outside, this third preferred embodiment enables path formation from the outer boundary of journal hole array  31  generally toward the center. Thus rotational-magnetic ring crank  89 , in conjunction with journal board  30 , provides the means for the unique outside-in format of play. 
         [0106]    Referring to  FIGS. 9A-9C  rotational-magnetic playing pieces  62 A, B, and C are placed in several clusters which form small paths linked to the inner parameter  93  of rotational-magnetic ring crank  89 . Accordingly, the rotational-magnetic playing pieces  62 A, B, and C will spin with rotation of rotational-magnetic ring crank  89  by actuating rotational-magnetic ring crank  89 . 
         [0107]    Circular journal board  30  is characterized with a top surface  35  and bottom surface  36 . Annular slot  32  extends below top surface  35  and is of sufficient width to accommodate ring body  90  of rotational-magnetic ring crank  89 . Annular slot  32  thus provides a means of concentrically locating ring body  89  around journal hole array  31  and maintaining a substantially fixed axis of rotation for rotational-magnetic ring crank  89 . Journal board  30  further comprises feet  34  which extend from bottom surface  36  and provide support to journal board  30 . Feet  34  preferably are rubber or a gripping material to counteract torque applied by rotational-magnetic ring crank  89  during play. While feet  34  are shown as three, a larger number of feet are likely preferred to prevent tilting of journal board  30  during manipulation of rotational-magnetic ring crank  89 . 
         [0108]    Ring crank  89  comprises ring body  90  having top face  92 , bottom face (not shown), inside face  93  and outside face  94 . Internal magnets  96  are displaced in a circular pattern near inside face  93 . Circular pattern of internal magnets  96  are characterized with an alternating radial polarity whereas alternating north and south poles are oriented inward toward journal hole array  31  to facilitate magnetic coupling with rotational-magnetic playing pieces  62 A, B and C. Internal magnets  96  are also characterized with a substantially equivalent circular pitch as radial magnets  23  or rotational-magnetic playing pieces  62 A, B and C. Thus rotational-magnetic ring crank provides inward magnetic coupling with rotational-magnetic playing pieces  62 A, B and C when placed in journal hole array  31  in a pivot position proximal to inside face  93  such that when rotational-magnetic ring crank  89  is rotated, one or more rotational-magnetic playing pieces  62 A, B and C will also rotate and experience relative motion. In the embodiment shown ring body  89  comprises  108  rectangular magnets  96  around inside face  93 . 
         [0109]    According to the third preferred embodiment, rotational-magnetic ring crank  40  also comprises revolving handle  97  extending from top face  92  of ring body  91 . Revolving handle  97 , being able to freely spin and being mechanically coupled to ring body  91 , enables a player to operate the rotational-magnetic ring crank  89  like a crank to provide continuous rotation. Rotational-magnetic ring crank  89  is preferably made of a low friction polymer material or alternatively comprises a low friction film affixed to contacting faces  95  and  93  or  94 . 
         [0110]    Optionally ring body  90  may further comprises a catch means (not shown) which interfaces with an undercut (not shown) of journal board  30  to prevent rotational-magnetic ring crank  89  from dislodging out of annular slot  32  during manual revolution of rotational-magnetic ring crank  89 . Such catch means could be a snap-fit interface or utilize spring plungers which lock into a recess to maintain attachment of rotational-magnetic ring crank  89  to journal board  30 . Although a retention means can optionally be added, this is not instrumental for practicing the inventions whereas, in most embodiments, rotational-magnetic ring crank  89  is of sufficient mass not to be easily dislodged from annular slot  32  of journal board  30 . 
         [0111]      FIGS. 10A-10E  show a particular configuration pertaining to a circular journal board embodiment whereas rotational-magnetic playing piece  62 A, B, and C are arranged in a symmetrical pattern in which a cross is formed within journal hole array  32 . Centrally located large rotational-magnetic playing piece  62 A, is magnetically coupled to all four arms of the cross formation and accordingly a larger gap is permitted between adjacent rotational-magnetic playing piece  62 C than would be necessary of centrally located rotational-magnetic playing piece  62 A was magnetically coupled to only a single rotational-magnetic playing piece. Optionally, the centrally located large rotational-magnetic playing piece  62 A could be replaced with a rotational-magnetic disk crank  74  as shown in previous embodiments allowing rotary motion to be initiated by actuating central disk crank  74  or by actuating the ring crank  89 . In this scenario, since the disk crank  74  (not shown) would be coupled to ring crank  89  via four magnetically coupled arms or rotational-magnetic playing pieces, sufficient torque would be provided to rotate ring crank  89  via hand rotation of the optionally placed disk crank  74  (not shown). 
         [0112]    A particular advantage of the third preferred embodiment of  FIGS. 9-10E  is the ability to magnetically couple rotational-magnetic playing pieces  62 A, B and C directly to the rotational-magnetic ring crank  89  so as to have stronger magnetic coupling through all linked paths and to generate higher torques in overcoming the inclination for magnetically coupled rotational-magnetic playing pieces  62 A, B or C to lock up. Another advantage to this embodiment as that as additional rotational-magnetic playing pieces  62 A, B and C are added in producing translated motion, a player can feel by touch a gradually increased force required to spin rotational-magnetic ring crank  89 . This tactile aspect of play offers an added dimension to the game as the player can actually “feel” the consequences of particular rotary playing piece placement and predict the increasing likelihood of the “gear train” locking up. 
         [0113]    Referring to  FIGS. 11A-11E , various configurations of large medium and small cover plates  80 A-H,  81 A-H,  82 A-H are shown adapted for attachment of large, medium, and small rotational-magnetic playing pieces  62 A, B, and C respectively. Each of large cover plates  80 A-H comprise oblong hole  83 A for fitting on slender oblong handle portion  65 A of large playing piece  62 A. Each of medium cover plates  81 A-H comprise oblong hole  83 B for fitting on slender oblong handle portion  65 B of medium playing piece  62 B. Each of small cover plates  82 A-H comprise oblong hole  83 C for fitting on slender oblong handle portion  65 C of small playing piece  62 C. 
         [0114]    In reference to  FIG. 11A , graphical cover pieces  80 A,  81 A, and  82 A are provided with graphical elements to indicate radial polarity and assist in visualizing magnet coupling (i.e., meshing) between rotational-magnetic playing piece  62 A, B, and C. Preferably a high contrast is provided between visual indications means. For example large medium and small visual indication means  87 A,  88 A, and  89 A respectively is designed with a dark color or pattern to represent outward north while a light color or patter is adapted to represent outward south polarity. 
         [0115]    With regard to  FIG. 11B , light and dark pie shaped sections are not intended to represent magnetic polarity but allow a user better visualize motion at higher rotational speeds than the cover pieces of  FIG. 11A  since higher rotational speeds would be required for larger graphical elements to appeared blurred during dynamic motion. 
         [0116]    With regard to  FIG. 11C , pie shaped graphical elements are provided in large, medium and small graphical indication means  87 C,  88 C, and  89 C respectively whereas each pie shaped element is provided with incrementally increasing darkness or shift in color. When rotational-magnetic playing piece  62 A, B, and C are configured with large, medium and small cover plates  80 C,  81 C, or  82 C a strobe effect is visualized during dynamic rotation. Color signature of each pie shaped elements can be adapted to simulate a blinking light when undergoing rotary motion. 
         [0117]    With regard to  FIG. 11D  visual indication means  87 D,  88 D, and  89 D are provided in a toothed configuration which may or may not indicate alternating polarity of associated magnets. 
         [0118]    With regard to  FIG. 11E  visual indication means  87 E,  88 E, and  89 E are provided with a spiral for visualizing rotary motion. Perhaps spirals are one of best modes for visualizing rotary motion as they give the appearance of constant expansion when rotated in the proper direction. This is true if a counter-clockwise spiral is rotated clockwise or a clockwise spiral is moving counter-clockwise. As rotational-magnetic playing piece  62 A, B and C may be moving clockwise or counter-clockwise it is preferred to provide large, medium and small graphical cover plates  80 E,  81 E and  82 E respectively with a spiral on each side whereas the spiral is counter-clockwise on the top and clockwise on the bottom. This enables a person to configure all magnetically coupled rotational-magnetic playing piece  62 A, B and C to produce the visual effect of a spiral that is constantly expanding when the rotational-magnetic disk crank  74  or rotational-magnetic ring crank  89  is rotated. 
         [0119]    As shown in the visual indication means  87 E,  88 E, and  89 E of  FIG. 11E , graphical segments are superimposed within the spiral design to also indicate magnetic polarity of associated magnets. 
         [0120]    With regard to  FIG. 11F , circles are used as part of visual indication means  87 F,  88 F, and  89 F. 
         [0121]    With regard to  FIGS. 11G and 11H , a pinwheel type configuration is used for visual indication means of large, medium and small graphics  87 G,  88 G and  89 G. This produces a unique visual effect when undergoing rotary motion such that when spinning rotational-magnetic playing pieces  62 A, B, and C in one direction it appears to be spinning the opposite direction.  FIG. 12H  shows a dual pin-wheel design whereas it can be made to appear that the inward and outward portions of corresponding rotary playing pieces are spinning in opposite directions when undergoing rotary motion. 
         [0122]    Numerous other design and configurations of graphical indications means for rotational-magnetic playing pieces are envisioned under the scope of the present inventions. Graphical cover plates provided are removable and interchangeable as to allow a user to explore the visual effects of not only construction piece pattern arrangement but the selection of graphical cover plates to attach thereon. Thus the present invention of a rotational-magnetic construction set allows for a high degree of customization. 
         [0123]    Referring to  FIGS. 12A-12B  an alternative embodiment of a rotational-magnetic disk crank  174  and small rotational-magnetic playing piece  162 C is shown as if they were placed on a journal base board in a fixed spatial relationship. Although playing piece  162 C looks identical to playing piece  62 C of previous embodiments having the same parameter  173 C and disk crank  174  looks identical to disk crank  74  of previous embodiments having the same parameter  162 , the section view of  FIG. 12B  shows an alternative arrangement of magnetic elements according to the present invention. 
         [0124]    Referring to  FIG. 12B , a section view is shown along a line through disk bodies  164  and  164 C of rotational-magnetic disk crank  174  and small rotational-magnetic playing piece  162 C respectively. When placed in proximity on a journal board, rotational-magnetic disk crank  174  and small rotational-magnetic playing piece  162 C are magnetically coupled so that spaced apart north and north poles provided by radial magnets  169  cause rotation of small rotational-magnetic playing piece  162 C when rotational-magnetic disk crank  174  is rotated. This is facilitated primarily by the repulsion of like poles between proximally located disk bodies  164  and  164 C. Correspondingly, it is not necessary according to the present invention that playing pieces comprise magnetized elements of alternating outward polarity. Alternatively magnetized elements can work primarily under repulsion whereas the magnetized elements of all rotational-magnetic playing pieces are all arranged with the same outward polarity, such as shown in  FIG. 12B  with all facing outwardly north, or alternatively with all facing outwardly south. 
         [0125]    A significant advantage a construction set according to the alternative embodiment of  FIG. 12B  is that all rotational magnetic playing pieces would require half as many magnets as other embodiments utilizing magnets arranged in a circular pattern of alternating outward magnetic polarity, such as shown in  FIG. 5C . The magnetic elements account for a substantial portion of manufacturing costs and therefore cutting the number of required magnets in half will provide dramatic cost savings for manufacturing the device. 
         [0126]    Additionally, the alternative embodiment of  FIGS. 12A-12B  allows for a smaller radial pitch P 162 , and P 174  than as can practically be achieved with twice the number of magnets having the same widths. This allows circumferential spacing between magnets can be optimized for improved magnetic coupling performance. Additionally, the block magnet used could be of an increased radial thickness that what could otherwise not be used when having to pack twice the number of magnets within the same parameter. 
         [0127]    Like previous embodiments, the circular magnetic pitch P 174  of rotational-magnetic disk crank  174  and circular pitch P 162 C of rotational-magnetic playing piece  162 C are substantially equivalent according to the invention as needed for effective coupling between various sized playing pieces. Thus all rotational-magnetic construction pieces including disk crank  174  and large, medium and small rotational-magnetic construction pieces according to the present invention will have a substantially equivalent circular pitch for providing interchangeability whereas all rotational-magnetic construction pieces can be effectively coupled together. 
         [0128]    The maximum working depth Dw of  FIG. 12B  and of  FIG. 5C  may or may not be equivalent based on the particular design of rotational magnetic playing pieces of the same type as disk crank  173  and playing piece  162 C. Although a fewer number of magnetized elements are involved, the mass, shape and positioning of the magnetized elements  169  can be optimized to provide nearly equivalent magnetic coupling performance as pertaining to previous embodiments having twice the number of magnets  69  with alternating outward polarity. 
         [0129]    Other embodiments within the scope of the invention include rotational-magnetic playing pieces configured for magnetic coupling whereas embedded magnets of some rotary playing piece are all arranged in an outward north polarity while playing pieces within the construction have magnets all arranged with an outwardly south polarity. Correspondingly, the principal magnetic interaction between proximally placed rotational playing pieces could be either repulsion or attraction depending on the combination. For example, if a playing piece of outwardly north magnetization was placed near a playing piece of outwardly south magnetization the magnetic coupling would be primarily facilitated by the attraction of opposite poles of interacting magnets. On the other hand, if a playing piece of outwardly north magnetization was placed near a playing piece also of outwardly north magnetization, magnetic coupling between this pair would be facilitated by the repulsion of like poles of interacting magnetic. 
         [0130]    In addition, it is envisioned within the scope of the invention to include magnetically susceptible ferromagnetic or “soft magnetic” material between or around permanent magnets to help direct magnetic flux and to optimize magnetic coupling between rotational-magnetic playing pieces. 
         [0131]    Although magnetic elements are shown as block magnets, alternative embodiments could utilize magnets that are cylindrical, pie-shaped or of other variable geometry. 
         [0132]    Although the present invention has been described herein with reference to a particular embodiment, it will be understood that this description is exemplary in nature and is not considered as a limitation on the scope of the invention. The scope and spirit of the present invention is therefore only limited by the appended claims and the reasonable interpretation thereof.