Abstract:
An asymmetrical capacitor module for generating thrust includes two conductive elements of similar but different geometries separated by a dielectric member. Improved embodiments provided in the construction of conductive elements of smaller axial extent include those where the element is formed by an annular wire or a dielectric supported ring. Other embodiments concern the dielectric member and involve changes in the extent and shape thereof.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part of co-pending U.S. application Ser. No. 09/520,817, filed on Mar. 8, 2000. 
     
    
     ORIGIN OF THE INVENTION  
       [0002] This invention was made by an employee of the United States Government and may be manufactured and used by or for the Government for Governmental purposes without the payment of royalties. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0003]    1. Field of Invention  
           [0004]    The present invention relates to methods and apparatus which use capacitors charged to high potentials for generating thrust and, more particularly, to an improved apparatus using a two dimensional, asymmetrical capacitor to which a high potential is applied.  
           [0005]    2. Background of the Invention  
           [0006]    It is well established in the literature, that a force or thrust may be generated by a capacitor charged to a high potential. Although there are different theories regarding the basis for this phenomenon, there is no dispute that a force is generated by capacitors under such high voltages. However, the thrust generated by such high potential capacitors has been minimal and thus this phenomenon has had very limited practical utility.  
           [0007]    In the above-identified application, there is disclosed a capacitor module system for creating a thrust. The system includes a capacitor module comprising a first conductive element having a cylindrical geometry; a second conductive element which is axially spaced from the first conductive element and which is of a geometry having a smaller axial extent than the first conductive element; and a dielectric element disposed between the first conductive element and the second conductive element so as to form the capacitor module. A high voltage source, having first and second terminals connected respectively to the first and second conductive elements is used to apply a high voltage to the conductive elements of sufficient value to create a thrust force on the module to thereby induce movement thereof. As disclosed in that application, in preferred embodiments, the first conductive element can comprise a solid cylinder or a hollow cylinder. The second conductive element can comprise a disk, a domed element, or a tip at the end of a dielectric rod. The system may further include a plurality of circumferentially disposed, spaced dielectric rods which interconnect the dielectric element and the second conductive element.  
           [0008]    Although the asymmetrical capacitor module described in the preceding paragraph has worked well in the laboratory, one potential disadvantage or limitation thereof is that there is some tendency to arcing between potential surfaces. More generally, there is a need to further improve the module construction to enable use thereof for atmospheric propulsion and for propulsion in space.  
         SUMMARY OF THE INVENTION  
         [0009]    In accordance with the invention, an asymmetrical capacitor module is provided which affords important advantages over those disclosed in the above-identified application, particularly in the areas of performance, weight reduction and arcing between conductive surfaces.  
           [0010]    In accordance with a first aspect of the invention, a capacitor module system is provided for creating a thrust force, the system comprising: a capacitor module comprising a first conductive element having a first geometry; a second conductive element axially spaced from the first conductive element and having a geometry of smaller axial extent than the geometry of the first conductive element; and a dielectric element disposed between the first conductive element and the second conductive element so as to form the capacitor module; and, a high voltage source, having first and second terminals connected respectively to said first and second conductive elements, for applying a high voltage to the conductive elements of sufficient value to create a thrust force on the module inducing movement thereof, the second conductive element having a diameter substantially equal to that of the first conductive element and being of a shape defining a plane as viewed in axial cross section while being of reduced weight compared with a copper disk of the same diameter and shape.  
           [0011]    In one preferred embodiment, the second conductive element comprises an insulator including a plurality of conductive elements therein.  
           [0012]    In another preferred embodiment, the second conductive element comprises a circular conductive wire member.  
           [0013]    In yet another preferred embodiment, the second conductive element comprises a cup-shaped conductive member having a recessed central portion.  
           [0014]    In still another preferred embodiment, the second conductive element comprises an annular conductive member disposed within an outer dielectric annulus. Advantageously, the second conductive element further includes a central disk-shaped dielectric member.  
           [0015]    In one preferred implementation, the first conductive element is of a cylindrical shape.  
           [0016]    In another preferred embodiment, the apparatus further comprises a central dielectric support strut for supporting the second conductive element in spaced relation to the dielectric element.  
           [0017]    According to a further aspect of the invention, a capacitor module system is provided for creating a thrust force, wherein the system comprises: a capacitor module comprising a cylindrical dielectric member having an outer surface; a first conductive element disposed on the outer surface of said dielectric member and having a cylindrical geometry; a second conductive element disposed on said dielectric member in axially spaced relation to said first conductive element so as to form the capacitor module and having a cylindrical geometry of smaller axial extent than said first conductive element; the dielectric member extending axially beyond the first conductive element at one end of said dielectric member and extending axially beyond said second conductive element at the opposite end of said dielectric member; and a high voltage source, having first and second terminals connected respectively to said first and second conductive elements, for applying a high voltage to said conductive elements of sufficient value to create a thrust force on the module thereby inducing movement thereof.  
           [0018]    In an important implementation that reduces arcing, the dielectric member includes a window therein between said first and second conductive elements.  
           [0019]    In one embodiment, the dielectric member includes first and second parts, the first conductive member being disposed on the first part and the second part comprising cylindrical end member joined to said first part and said second conductive element comprising an annular conductive member recessed within said second part. As above, in this embodiment, the dielectric member preferably includes a window located between the first and second conductive elements.  
           [0020]    In accordance with a further aspect of the invention, there is provided a capacitor module system for creating a thrust, said system comprising: a capacitor module comprising a first conductive element having a first geometry; a second conductive element axially spaced from said first conductive element and having a geometry of smaller axial extent than the geometry of said first conductive element; and a dielectric element including a first frusto-conical portion disposed between said first conductive element and said second conductive element so as to form the capacitor module, said dielectric member including a further portion having an outer surface on which said first conductive element is disposed; and, a high voltage source, having first and second terminals connected respectively to said first and second conductive elements, for applying a high voltage to said conductive elements of sufficient value to create a thrust force on said module inducing movement thereof.  
           [0021]    Preferably, the further portion of the dielectric member is of a frusto-conical shape.  
           [0022]    In one embodiment, the first portion of the dielectric member comprises first and second frusto-conical portions joined end to end.  
           [0023]    Advantageously, the second conductive element is of a frustoconical shape.  
           [0024]    Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]    [0025]FIG. 1 is a perspective view of an asymmetrical capacitor module in accordance with a first embodiment of the invention;  
         [0026]    [0026]FIG. 2 is a broken away perspective view of an asymmetrical capacitor module in accordance with a further embodiment of the invention;  
         [0027]    [0027]FIG. 3 is a broken away perspective view of an asymmetrical capacitor module in accordance with another embodiment of the invention;  
         [0028]    FIGS.  4 ( a ),  4 ( b ) and  4 ( c ) are a perspective, end elevational and cross-sectional view, respectively, of yet another embodiment of the asymmetrical capacitor module of the invention;  
         [0029]    [0029]FIG. 5 is an end elevational view of an asymmetrical capacitor module in accordance with still another embodiment of the invention;  
         [0030]    [0030]FIG. 6 is a perspective elevational view of a further embodiment of an asymmetrical capacitor module according to the invention;  
         [0031]    FIGS.  7 ( a ) and  7 ( b ) are a perspective view and an end elevational view, respectively, of another embodiment of an asymmetrical capacitor module according to the invention;  
         [0032]    [0032]FIG. 8 is a side elevational view of another embodiment of the invention; and  
         [0033]    [0033]FIG. 9 is a side elevational view of a further embodiment of the invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0034]    Referring to FIG. 1, there is shown a perspective view of a two dimensional, asymmetrical capacitor module  10  in accordance with a first embodiment of the invention. The capacitor module  10  is very similar in outward appearance to that disclosed in the above-identified application Ser. No. 09/520,817, and includes, at one end thereof, a cylinder  12  made of copper or another highly conductive material. The cylinder  12  can be solid or hollow. The module  10  also includes, axially spaced from cylinder  12  at the other end of module  10 , a cylindrical conductive disk  14  made of copper or another highly conductive material. In the embodiment of FIG. 1, a cylindrical dielectric element  15 , which is made of Kapton or another high voltage dielectric material, is affixed to cylinder  12  on the side of cylinder  12  closest to the cylindrical disk  14 . A plurality of dielectric rods or struts  16  are provided which join the disk  14  and the dielectric cylinder  15 . The dielectric rods  16  are attached, at one end thereof, about the periphery of the dielectric cylinder  15 . These dielectric rods  16  extend axially across an air gap  18  and are attached, at the other end thereof, to the disk  14 . A support post  11  extends outwardly from the cylindrical dielectric element  15 . Support post  11  is preferably made of Kapton or another high voltage dielectric material.  
         [0035]    A high voltage supply  13  is also provided. The high voltage supply  13  has first and second terminals respectively connected to the flat cylindrical disk  14  and the cylinder  12  which form the axial capacitor plates of the capacitor module  10 . The voltage of the voltage supply  13  is such to charge the capacitor module  10  to a sufficiently high potential to cause a thrust or force to be generated which causes axial movement of the capacitor module  10 .  
         [0036]    The only difference between the embodiment of FIG. 1 and one of those disclosed in the above-identified application is that, in the latter, disk  14  is made completely of copper or another suitable material, while, in the embodiment of FIG. 1, disk  14  is made of an insulator including a plurality of highly conducting (e.g., copper) needles or rods penetrating the insulator, as is indicated very generally by the multiple arrows shown in FIG. 1.  
         [0037]    Referring to FIG. 2, wherein corresponding elements have been given the same reference numerals with a “2” replacing the “1” in the tens place, a further embodiment of the invention is shown. In this embodiment disk  14  is replaced by a ring or annulus preferably in the form of a fine wire  24  made of copper or another highly conductive material.  
         [0038]    Referring to FIG. 3, wherein corresponding elements have been given the same reference numerals with a “3” replacing the “1” in the tens place, a further embodiment is shown, wherein a disk  34 , preferably made as described above in connection with FIG. 1, is supported by a single central strut  30  made of high voltage dielectric material.  
         [0039]    Referring to FIGS.  4 ( a ),  4 ( b ) and  4 ( c ), wherein corresponding elements have been given the same reference numerals as in FIG. 1 with a “4” replacing the “1” in the tens position, a further embodiment is shown wherein a disk  44  is provided which is hollowed out, i.e., the disk  44  comprises a very shallow cup-shaped member with a thin base portion  44   a  and a cylindrical side wall  44   b , as is perhaps best seen in FIG. 4( c ).  
         [0040]    Referring to FIG. 5, wherein corresponding elements have been given the same reference numerals as in FIG. 1 with a “5” replacing the “1” in the tens place, a further embodiment is shown wherein a ring or annular conductor  54 , similar to that of FIG. 2, is employed. In this embodiment, ring conductor  54  is mounted within and partially encapsulated by a dielectric disk  54   a  and an outer dielectric ring or annulus  54   b . The mounting support for ring conductor  54  may be a plurality of struts (not shown) similar to those of, e.g., FIG. 2.  
         [0041]    Referring to FIG. 6, wherein the same basic numbering scheme is employed, there is shown a further embodiment of the invention, which provides improvement in performance and affords a weight reduction as well as a reduction in arcing. In this embodiment, the rear conductor  62  and a front conductor  64  are both formed by respective conductive coatings on the surface of a hollow dielectric sleeve or cylinder  60  which extends well beyond conductors  62  and  64  at both ends thereof. Although the basic construction need not include this feature, arc reduction is effected by providing a window  67  in the portion of hollow sleeve  60  between conductive surfaces  62  and  64 .  
         [0042]    A similar embodiment to that of FIG. 6 is shown in FIGS.  7 ( a ) and  7 ( b ) wherein the same basic numbering scheme is again used. As in the embodiment of FIG. 6, the rear conductor  72  is formed of a conductive coating on the surface of a dielectric sleeve  70  and a window  77  is also provided. However, in this embodiment, the front conductor  74  is formed by a recessed conducting ring located within an outer cylindrical or annular dielectric member  78  affixed to the front end of sleeve  70  so that, again, the dielectric member  78  extends well beyond conductor  74 . An inner dielectric ring or annulus  79  is disposed concentric with, and within, recessed conducting ring  74 .  
         [0043]    Yet another embodiment of the invention is shown in FIG. 8, wherein the same numbering scheme is used. In this embodiment, a dielectric sleeve or body  80  of a frustoconical configuration is employed. A rear conductor  82  is provided by a conducting surface on a less severely tapered portion of body  80 . A separate front conductor  84  is also formed by a conducting surface or coating and is also of frustoconical shape. A central dielectric strut or post  86  supports front conductor  84 .  
         [0044]    Referring to FIG. 9, an embodiment is shown which is similar to that of FIG. 8 but in which body a dielectric  90  includes two frustoconical portions  90   a  and  90   b  joined together at the respective bases thereof. A rear conducting surface  92  is provided on a third less severely tapered portion of dielectric body  90 . The front conductor  94  and supporting strut  96  are similar to that of FIG. 8.  
         [0045]    Although the invention has been described above in relation to preferred embodiments thereof, it will be understood by those skilled in the art that variations and modifications can be effected in these preferred embodiments without departing from the scope and spirit of the invention.