Magnetic apparatus appearing to possess only a single pole
BACKGROUND OF THE INVENTION 
     This invention relates generally to magnetic devices, and more particularly concerns magnetic segments that may be joined together to form a unitary body that appears to possess only a single pole. 
     It is commonly believed that each magnetized object has both a north pole and a south pole. While this appears to be true, no way was known, to my knowledge, to provide a unitary body possessing only unipolar characteristics to the external observor, so that the effects of the opposite pole were isolated. 
     SUMMARY OF THE INVENTION 
     It is a major object of the invention to provide a body appearing to have unipolar characteristics, and also to provide magnetic segments that may be assembled to form such a body. Accordingly, a major object of the invention is to provide: 
     (a) a magnetic segment having a north pole at one end and a south pole at its opposite end, said ends having generally polygonal outline, with the number of polygonal sides being a multiple of 3, 
     (b) the segment having sides shaped to closely interfit the sides of like segments when the segments are assembled into a generally circular cross section form with the opposite ends of each segment spaced apart along a radius of said form. 
     As will appear, such segments may be assembled into generally spherical form with the opposite ends of each segment spaced apart along a spherical radius, thereby to provide an apparently unipolar, unitary body. Another example is a toroid. 
     Further objects include the provision of such segments which are alike with opposite ends having polygonal outline L hexagonal or triangular for example; and the provision of segments which consist of permanently magnetized material or material subject to magnetization, as for example iron adapted to serve as a solenoid. Also, a non-magnetic core may mount the segments. 
     These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following description and drawings, in which: 
    
    
     DRAWING DESCRIPTION 
     FIG. 1 is a perspective view of a magnetic segment; 
     FIG . 2 is a generally spherical body incorporating segments as seen in FIG. 1; 
     FIG. 2a is a section through FIG. 2, on lines 2a--2a thereof; 
     FIG. 3 is a view like FIG. 1, showing a modified magnetic segment; 
     FIG. 4 is a view like FIG. 3, showing yet another modified segment; FIG. 4a is a section of a part of FIG. 4. 
     FIG. 5 is an exploded view showing a modification; 
     FIG. 6 is an elevation showing a toroidal form; and 
     FIG. 7 is an exploded view of a section on lines 7--7 of FIG. 6. 
    
    
     DETAILED DESCRIPTION 
     Referring first to FIG. 1, a magnetic segment 10 has opposite ends 11 and 12, and six flat sides 13-18. The intersections of the sides with the ends are indicated by the lines 13a-18a and 13b-18b. The intersections of the sides are indicated by the lines 19-24. Each of the sides 13-18 is like all the others, and the linear intersections 13a-18a form a hexagon, as do the linear intersections 13b-18b. 
     The segment 10 consists of permanently magnetized material, such as ALNICO, for example. Accordingly, the ends 11 and 12 define north and south poles, or vice versa. Ends 11 are larger than ends 12. 
     It will be seen that the segment sides are shaped to closely interfit one another when assembled into a generally spherical unitary body form as in FIG. 2, with the opposite ends 11 and 12 of each segment spaced along a spherical radius. See also FIG. 2a, where ends 11 define north poles and ends 12 define south poles, for example. The enclosed hollow at the center of the apparatus is designated at 26. The sides of the segments may be bonded together so as to very closely interfit. 
     Alternatively, external holder means 27 may be wrapped about the apparatus to hold the segments in position, with their sides in very closely engaged position. All sides 13-18 of each segment are engaged by like sides of other segments; so that central hollow 26 is completely enclosed. Accordingly, from the exterior, the apparatus appears as a unipolar device, i.e. it appears as a north pole, (or alternatively a south pole if ends 11 have south pole magnetization). 
     In FIG. 3, the modified magnetic segment 30 has opposite ends 31 and 32, and three like sides 33-35. The latter intersect the ends at lines 33a-35a and 33b-35b. Lines 33a-35a form an equilateral triangle, and lines 33b-35b also form an equilateral triangle. Six of the segments 30 may be interconnected to form one of the segments 10, i.e. so that the six ends 31 form end 11, and the six ends 32 form end 12. 
     In FIG. 4, the magnetic segment 100 is exactly like that in FIG. 1; however, it is not a permanent magnet, but rather an induced magnetic segment. It may be defined by a solenoid that includes the segment plus coil 40 about the segment as in FIG. 4a. As there shown, the square cross-section wire 40 exactly fits the square cross section groove 41 in the segment material 100. A source of electrical current, such as battery 102 is connected with coil 40, via switch 103, to effect magnetization of the segment. 
     In FIG. 5, the segments, as at 50, are attached to a non-magnetic core 51 of spherical outline form. For example, the core may consist of plastic, or aluminum, these being examples only. A holding screw 52 fits in a radial bore 53 in the segment, the latter having a peripheral outline like that of segments seen in FIG. 1 or 3. The screw thread attaches to a threaded bore 54 in the core, and the screw head seats against shoulder 55 at the inner end of a larger radial bore 56 in the segment. A plug magnet 57 finally fits into the bore 56 to fill it. The plug magnet may be bonded to bore 56. All segments fit side by side as in FIG. 2. 
     In FIGS. 6 and 7 an externally unipolar toroid 60 includes magnetic segments 61 attached to an annular non-metallic core 62, so that either the north or the south pole ends of all segments are presented outwardly, as seen in FIG. 7. Four segments, for example, may be spaced about the core in a cross section as in FIG. 7. Screws 63 are received in bores 64 in the segments, and attach them to the core, as in FIG. 5. All segments fit side-by-side, so that the surface of the FIG. 6 toroid appears unipolar.