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2-Eae See at TORNEY May 25, 1965 A May 25, 1965 A. SEARS 3,185,877 DIRECT CURRENT HOMOPOLAR GENERATOR Filed Jan. 4, 1963 2. Sheets-Sheet ANTHoNY SEARS 2-eae see AT TORNEY May 25, 1965 A. SEARS 3,185,877 DIRECT CURRENT HOMOPOLAR GENERATOR Filed Jan. 4, 1963 2. Sheets-Sheet 2 reAyala YaYaawaawasara aaaaaSalass as a Wa %Ma Ya YaYa 222222222222222222227ZZZZZZ2 vaaaaaaaaaaaaaaa YaYa Ya W. Wayawa WW R 22 fa2SENE7-2 INVENTOR ANTHONY SEARS 2. 262-26/ AORNEY 3,185,877 United States Patent Office Patented May 25, i965 r 4. producing means or members 2 and 14 are extended 3,185,877 DRECT CJRENT OGPOLAR GENERATOR radially outward and tapered or narrowed in the direc Aatheny Sears, New York, N.Y. tion of the radial outer periphery of the inductor struc (88-09 Shore Front Parkway, Rockaway Beach, N.Y.) ture 6. The narrowed tapered outwardly directed por 5 tions of the field producing members 12 and 14 are Fied Jan. 14, 1963, Ser. No. 251,398 identified by the numeral 32 in accordance with the i0 Clais. (C. 3i 0-115) teaching of applicant's copending application. It is be This invention relates to homopolar generators and in lieved this arrangement enables or causes the electrons particular to centrifugally operated direct current genera to move radially outward under centrifugal forces ap tors of the type disclosed in co-pending United States IO plied to them during the rotation of the rotor structure. patent application Serial No. 21,759, filed April 12, 1960, AS these electrons are caused to move radially outward, now Patent No. 3,096,454. they are directed in their path of movement by the The desideratum of this invention is to provide a homo progressively narrowing portions 32 of the field produc polar or unipolar generator in which, although the rotor ing members 12 and 14. has no moving parts other than that of its own rota The rotor structure is enclosed in a non-magnetic tion, the voltage and amperage or current output of the housing 34 that is Supported above the base 28 by brackets generator is capable of being selectively and predeter 36. The housing encloses substantially the whole of the inately varied. rotor structure except that it permits the extension there Another purpose and object of the invention is to beyond of the axial ends of the shaft 22 and, in addi provide a generator in which non-Solid brushes or cur 20 ticin, a radial inwardiy disposed portion of the inductor rent withdrawing contacts may be employed, thereby structure 16 for a purpose to be described. The hous reducing brush wear and loss of operating time of the ing 34 provides a fluid-tight cover about the principal generator because of the necessity to repair or replace portion of the rotor structure. To accomplish this, any worn brush contacts. Accordingly, a feature of the in suitable and convenient fluid seal 38 may be provided vention resides in the ability to use fluid brush contacts between the enclosing portions of the housing 34 about or other non-Solid electrolytic brush contacts that are the shaft 22 and inductor structure 16 as diagrammati not as susceptible to wear and break down as solid carbon cally shown in FIG. 2. type brush contacts in common use. Mounted on the housing 34 that is held stationary by Still another object of the invention is to provide an the brackets 36, is a set or pair of shunt coils 40 con inductor structure as an integral rotating part of the 30 nected in Series to an exciter 42 or suitable source of rotor and its magnetic field producing structure and current. When the shunt coils 40 are energized, a mag wherein Such inductor structure is constructed to en netic field is caused to be produced by the members 12 able the production of a desired current output. and i4. The Inagnetic field is unidirectional and moves Other and further objects of this invention reside in in the direction from the north pole member 12 to the the structures and arrangements hereinafter more fully South pole member 14 and directed through the induc 'described with reference to the accompanying drawings tor structure 16 positioned therebetween. The induc in which: tor Structure 6 includes a pair of radially spaced con FIG. 1 is a perspective view of a direct current gen tacts or contact elements 44 and 46. The contact 44 is erator constructed according to the teaching of the ii positioned on the inductor structure 16 at a greater out vention, 40 Ward radial distance than the contact 46. FIG. 2 is a vertical cross section of FIG. 1, During the rotation of the rotor structure, a direct FIG. 3 is a perspective view of the inductor of FIG. Current is induced in the inductor structure 16 as dis 2, and closed in the aforementioned co-pending application. FiG. 4 is a perspective view of a modified form of The induced current is capable of being withdrawn from inductor structure. 45 the inductor Structure by placing an electrically conduc Referring now to FIGS. 1, 2 and 3 of the drawings, tive brush element in engagement with the contact 44 the generator there shown is generally identified by the and completing a circuit across the inductor structure numeral 10. The generator E0 comprises a rotor struc 16 by connecting a further brush in engagement with ture that includes as integral and unitary rotating parts the contact 46. In the prior art, carbon type brush con thereof, magnetic field producing means 2 and 4 com tacts have been commonly employed for the purpose posed of a miagnetizable material, and a radially disposed of withdrawing current from a generator. However, or directed inductor structure generaily identified by because of the extremely high speeds of rotation and the numeral i6. The inductor structure E6 is securely the constant brush engagement with the generator arma mounted to and for simultaneous or conjoist rotation 5 5 ture, the brush contacts tend to wear rapidly and re with the members 12 and 4 by bolts 18. The inductor quire frequent repair and replacement. To do this, it Structure i6 is fully insulated about all of its surfaces is necessary to shut down the operation of the generator that are positioned adjacent to the magnetic field pre and perform the repair work. The procedure is costly ducing members 2 and 14 by the insulating material 26. in time and in the loss of use of the generator equip The rotor structure, as broadly described, is mounted O et, On a non-ferrolls or non-magnetic shaft 23. The shaft 22 The present invention enables the use of a fluent or is Supported for rotation in bearings 24 that are con flowing type of non-solid electrolytic brush elements for tained in supporting arms 26 forming uprights of and e:ngagement with the continuous contacts 44 and 46. In connected to a base 28. The shaft 22 is rotated by any referring to FIG. 2 of the drawing, it will be noted that convenient drive mechanism (not shown), connected with tile housing 34 encompassing and enclosing the rotor a pulley 36 mounted at one end thereof and is insulate Stricture is provided with a stand pipe 48 that may be in from the inductor 6 by the insulating material 23. the form of a sight glass through which an electrically The rotor structure includes the magnetic field pro coil dictive fiuid or non-Solid electrolytic type material, as ducing means 12 and 14, the inductor structure E6 and linercury, may be poured into and visually observed at the rotating shaft 22, all of which rotate as a single a lower insulated brush holder 50 defined as an integral unit and is held together by the bolts i3 that are ade part of the housing. The non-solid brush contact mate quately insulated along their lengths. The pagnetic field rial 52 will flow about the contact 44 of the inductor struc 3,185,877 3 4 ture 16 and remain in constant flowing engagement with substantially the same in construction as that of the pre the same during the rotation of the rotor structure and viously described inductor structure 16 except, however, the inductor structure 16. that the radial outer contact 44 is connected with the ra In a similar manner, an insulated brush contact holder dial inner contact 46 by one or more or by a plurality 54 is provided about the portion of the inductor structure of electrically conductive elements 166a and 166b. Each 16 that extends axially beyond the housing 34 and encom one of the conductive elements 166a and 166b has a plu passes the radial inner inductor contact 46 fluid-tightly. rality of turns that are spirally wound over and insulated The insulated holder 54 is formed with a stand pipe type from the other by the insulating material 20. sight glass 56 through which the fluent electrically con In the embodiment of the inductor structure 116 shown ductive non-solid electrolytic brush material 52 may be O in FIG. 4, it will be recognized that the inductor elements supplied to and observed in the holder for engagement 116a and 116b form a double spiral or double start, of with the periphery of the inductor contact 46. Thus, both which each spiral is wound over the other and extends contacts 44 and 46 of the inductor structure 16 are con from one of the radially disposed contacts 44 to the other stantly engaged by a fluid or flowing type non-solid elec contact 46 to connect the same in an electrical circuit.
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