US2602118A - Capacitive rotatable coupler - Google Patents
Capacitive rotatable coupler Download PDFInfo
- Publication number
- US2602118A US2602118A US609692A US60969245A US2602118A US 2602118 A US2602118 A US 2602118A US 609692 A US609692 A US 609692A US 60969245 A US60969245 A US 60969245A US 2602118 A US2602118 A US 2602118A
- Authority
- US
- United States
- Prior art keywords
- plates
- rotatable
- transmission lines
- coupler
- transmission
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/06—Movable joints, e.g. rotating joints
- H01P1/062—Movable joints, e.g. rotating joints the relative movement being a rotation
- H01P1/066—Movable joints, e.g. rotating joints the relative movement being a rotation with an unlimited angle of rotation
- H01P1/068—Movable joints, e.g. rotating joints the relative movement being a rotation with an unlimited angle of rotation the energy being transmitted in at least one ring-shaped transmission line located around the axis of rotation, e.g. "around the mast" rotary joint
Definitions
- This invention relates to a rotatable coupler for the transmisson of alternating current between two transmission lines rotating with respect toone. another, andis. particularly directed to the capacitive type'of. such rotatable cou'pler.
- Rotatable couplers which. aroused to couple one transmission line to a second transmission line which: is connected" to; aiotatingl antenna commonly employ inductive gcoupling, which re 7 sults in rather sharp tuning and considerable restriction on the width of; theifrequency band passed.
- the frequency lbandi passed by ar ma able coupler employing capacitive coupling. is markedly broadenfthan that passed? by. a. rotat able couplerof the inductive ⁇ .
- this invention to provide a rotatablecouplenforsooupling two transmission lines, which; will j pass; radio frequency energy over arelativelyawide'band of frequencies.
- y I jv Q r It is another object; ofe'the. invention-to provide such arotatableocouplerwhich isstrong mechanically and ofsimple construction.
- Figure: 1 a diagrammaticrrepresentation of one embodiment or this'inventiom-and 1
- Figure 2 is asection viewer-an embodiment: c this invention showingcertain structural details thereof.
- Adequate means" of insulation'and support of the plates can be developed :for-any set of requirements, as this invention permits of considerable flexibility in choice; of the j dimensions of the plates; employed in anembodiment suchasris illustrated in: Figure 1 "which Was-designed t0? surroundi a rotating antenna mount having anrexternalz die ameter ofisomewhat less-.than twelve-inches: external diameter of; rings I-- and: 3+20-inches, internal diameter .of; rings I: and 3-1:7 inches, external diameter of rings” 2 and lie-16' inches, and internal diameter of ringsZ and l-h-l-zvinches.
- This. embodiment was usedwith goodiresultsto pass a frequency .--band of'abOutlO-rp'er cent-in the neighborhoodaof-200'mc,/s.
- converter 1* three parallel wire transmission lines I I, 12- and. t3: lead-to plates l and 2;
- the feed. points foranyone of transmissionw'lines H: through I willhereinafter be referred to as pairs of feed DOiljltSxiEOl.
- alternating voltages may be applied ion either ,side ofxthe rotatable 'couplerzand alternating current will v betransmitted through the coupler. If'an. alternetting voltage: is appliedito one wire of each; of parallel wire transmissionilines l l,f
- the number of parallel wire transmission lines feeding the upper and lower pairs of plates may be varied as desired and the flat impedance with relative rotation of the two'halves of the coupler will be retained, if the number of transmission lines feeding one pair of plates is neither a factor nor an integral multiple ofthe'number of transmission lines feeding the other pair of plates. For, if this numerical relationship is maintained, then at no time will more'than one pair of feed points for plates l and 2 be aligned radially with a pair of feed points for plates 3 and 4. V
- FIG. 2 shows in section how plates l and 2 may be rotatably mounted with respect to plates 3 and 4.
- Shaft 20 maybe, for example, an antenna pedestal supporting rotatably thereon shaft 2 I, journaled in bearing 22 of shaft 20.
- Attached to shaft 20 is an annular plate 23, and attached to shaft 2
- Plate l is attached to plate 24 by a number of insulators 25, and plate 2 is also attached to plate 24 by a number of insulators 26.
- plates'3 and 4 are attached to plate 23 through insulators 21 and 28, respectively; It will be seen that plates 1 and 2 will rotate with respect to plates 3 and 4 as shaft 2
- a rotatable coupler for the transmission of alternating electric current between two balanced transmission lines rotating with respect to each other comprising two coaxial annular conductin plates flxedwith respect to each other, a number of m of parallel wire transmission lines feeding said two plates, one wire of each of said "122. transmissionlines being connected to one of said plates at points spaced substantially degrees from each other and the other wire of each of said m transmission lines being con two plates at connection points spaced a 7 degrees from each other,'the'number "n being any number neither a factor nor an integral multiple of said number m, said "12.
- a rotatable coupler for the transmission of alternating electric current between two unbalanced transmission lines rotating with respect to eachother comprising two coaxial annularconducting plates fixed with respect to each'other, a number "m of parallel wire transmission lines feeding said two plates, one wire of eachof said 111. transmission lines being connected to one of said plates at points spaced substantially nected to the other of said plates at points having substantially the same radial positionsgas the corresponding points .of connection on said one plate, a line-balance converter feeding said fm transmission lines in parallel and being .fed by one of said two unbalanced transmission lines, third and fourth coaxial annular conducting plates fixed with respect to eachother and of substantially the same lateral dimensions as the first two plates.
- a rotatable 'couplerfor the transmission of alternating current between a first transmission line and a second transmission line which is rotatable relative to said first transmission line comprising a first set of coaxially disposed annular conducting plates, one for each conductor of the first line, a plurality of connections betweeneach conductor of the first line and a difierent one of said conducting plates at various angular points around the circumference of the plates, a second set of coaxiallyf disposed annular conducting plates, of similar dimension and located inclose proximity to the said first set of plates, and rotatable with respect thereto, one.
Landscapes
- Waveguide Connection Structure (AREA)
Description
y 1, 1952 R. J. ADAMS ETAL 2,602,118
CAPACITIVE ROTATABLE COUPLER Filed Aug. 8, 1945 gwoe/wtow ROBERT J. ADAMS LEE R. DOBLER Patented July 1,1952
"2,602,118 I "c raorr1vERo'r 'rABtE coUPLaaJ 3 'i that .1; Actin Washington, no and Iiee Ra: Dohler, United States Navy I 1 ApplicationrAug ust 8, 1945, Serial No. 609,692,.-
scams; (01. 178- 14) I (firantedfunder the act of March. 3; 1883, as w amended April" 30, 1928; 3'70 0. G.--757)P This invention relates to a rotatable coupler for the transmisson of alternating current between two transmission lines rotating with respect toone. another, andis. particularly directed to the capacitive type'of. such rotatable cou'pler.
Rotatable couplers. which. aroused to couple one transmission line to a second transmission line which: is connected" to; aiotatingl antenna commonly employ inductive gcoupling, which re 7 sults in rather sharp tuning and considerable restriction on the width of; theifrequency band passed. The frequency lbandi passed by ar ma able coupler employing capacitive coupling. is markedly broadenfthan that passed? by. a. rotat able couplerof the inductive}. typ'elfl r Furthermore, a capacitive/rotatable coupler may be constructed with a "diameter relatively small or quite large, as; is desired, whereas the diameter of the inductive type coupler is fixed within rather narrow limits by the frequency of the v lta e tobe passed, inaetheloop type cou pler must'not bemore than about oneequarter wave: length circumference; ;='Th6- capacitive type coupler thus allow swmore" flexibilityin design than the inductive=;type. i
It is accordingly: one obj ect of: this invention to provide a rotatablecouplenforsooupling two transmission lines, which; will j pass; radio frequency energy over arelativelyawide'band of frequencies. y I jv Q r It is another object; ofe'the. invention-to provide such arotatableocouplerwhich isstrong mechanically and ofsimple construction.
It is also an object of this z'mventionrtoprovide a, capacitive rotatable coupler for: coupling a transmission line toa rotating antenna,;which coupler may-have a large enough internal diameterthat it may bepositionedaround an antenna mount of relatively large external diameter;
It is another object of this invention to provide a capacitive rotatable coupler whose transmission characteristics will not vary greatly with the relative rotation of the upper element with respect to theilower elementofithe; coupler.
In the accor'npanying. drawings: a a
Figure: 1 a diagrammaticrrepresentation of one embodiment or this'inventiom-and 1 Figure 2is asection viewer-an embodiment: c this invention showingcertain structural details thereof.
In. the embodiment: of this invention; shown in Figure 1 concentric annulari conducting plates I andv 2', fixed with respect to" eachother, are similar in shape and difnens-ions to plates; 3; and I", which are also fixediwithrespecttto each other.
The distance" between the first: andr second pairs or of plates'is exaggerated inthe drawing; the'plates are in practice separated. byonlya. ,smalldistance; for example,'one-eighthzofan inch-l These four'platesi are positionedcoaxially sothat plates I and 2' rotatezwithres'pectto platesft'v and: 4 about their'common axis.
Adequate means" of insulation'and support of the plates can be developed :for-any set of requirements, as this invention permits of considerable flexibility in choice; of the j dimensions of the plates; employed in anembodiment suchasris illustrated in: Figure 1 "which Was-designed t0? surroundi a rotating antenna mount having anrexternalz die ameter ofisomewhat less-.than twelve-inches: external diameter of; rings I-- and: 3+20-inches, internal diameter .of; rings I: and 3-1:7 inches, external diameter of rings" 2 and lie-16' inches, and internal diameter of ringsZ and l-h-l-zvinches. This. embodiment was usedwith goodiresultsto pass a frequency .--band of'abOutlO-rp'er cent-in the neighborhoodaof-200'mc,/s.
In the; embodiment, of1F'igure; .1; the capacitive rotatable coupler servesnto' couple; unbalanced transmission line=5with unbalanced, transmission line 6.. Transmission line'5 feeds line-balance converter "1, while transmission line 6 feedslinebalance converter 8;
From line-balance; converter 1* three parallel wire transmission lines I I, 12- and. t3: lead-to plates l and 2; One wire. of. each of transmission lines ll, [2 and l-3zisconnected to plate I atfeed points 120 apart-from each other; while the other wire of each-of thesethree transmission lines. is connected to plate: 2 at feed points-:ha-ving substantially the same radial positions as of these "two transmission: lines is-Jconnectedto plate. 4 at feed pointshaving substantially the same radialpositions aswthe pointsrof connection-for plate 3; The feed. points foranyone of transmissionw'lines H: through I willhereinafter be referred to as pairs of feed DOiljltSxiEOl.
the. respectiveplates: I e
- Inrtheoperationi-of thisinvention,alternating voltages may be applied ion either ,side ofxthe rotatable 'couplerzand alternating current will v betransmitted through the coupler. If'an. alternetting voltage: is appliedito one wire of each; of parallel wire transmissionilines l l,f|:2 an
-f r x mpl With an alternating voltage-"oili The following dimensions: wereverse phase applied to the other wire of each of these three transmission lines, these alternating voltages will appear on capacitor plates l and 2. Alternating voltages of exactly the opposite phase will be inducedon the other capacitor plates 3 and v4, respectively, and will thus be impressed on transmission lines l4 and I5, causing alternating current to flow therein. Since the capacitor comprised of plates 1 and 3 and the capacitor comprised of plates 2 and 4 are of large capacitance, the capacitive reactance presented by this rotatable coupler tothe transmission of alternating current is very small.
It will be seen that as plates I and 2 rotate with respect to plates 3 and 4, at no time is more than one pair of feed points for plates l and 2 shown and described is exemplary only, and that the scope of the invention will be determined with reference to the appended claims.
The invention described herein may be manufactured, and used by or for.the Goyernment of the United States of America for governmental purposes without payment of any royalties thereon or therefor.
aligned radially with a pair of feed points for plates 3 and 4. If at any instant one pair of feed points for plates 1 and 2, say at the termination of transmissionline H, has'the same bearing as apair of feed points for plates 3 and 4, say at the termination'of transmission line"l4, then at this invention presents to alternating current of a given frequency an impedance which remains reasonably fiat, without any sharp peaks, as plates I and 2 are rotated through 360 withrespect to plates 3 and 4.
The number of parallel wire transmission lines feeding the upper and lower pairs of plates may be varied as desired and the flat impedance with relative rotation of the two'halves of the coupler will be retained, if the number of transmission lines feeding one pair of plates is neither a factor nor an integral multiple ofthe'number of transmission lines feeding the other pair of plates. For, if this numerical relationship is maintained, then at no time will more'than one pair of feed points for plates l and 2 be aligned radially with a pair of feed points for plates 3 and 4. V
Figure 2 shows in section how plates l and 2 may be rotatably mounted with respect to plates 3 and 4. Shaft 20 maybe, for example, an antenna pedestal supporting rotatably thereon shaft 2 I, journaled in bearing 22 of shaft 20. Attached to shaft 20 is an annular plate 23, and attached to shaft 2| is annular plate 24. Plate l is attached to plate 24 by a number of insulators 25, and plate 2 is also attached to plate 24 by a number of insulators 26. In the same way plates'3 and 4 are attached to plate 23 through insulators 21 and 28, respectively; It will be seen that plates 1 and 2 will rotate with respect to plates 3 and 4 as shaft 2|, supporting an antenna, for example, rotates with respect to shaft 20.
It will be understood that because of the width of the annular plates [through 4 slight lateral displacements of any of those plates will not result in'undue variations in the transmission characteristics of this rotatable coupler as transmission line 5 rotates'with' respect to transmission line 6.
In casethis invention is to be employed in coupling twobalanced transmission lines, the embodiment of Figure l'may of course be modified by elimination of line-balance converters I and 8. The operation of such a rotatable coupler would be in all other respects similar to that o the embodiment of Figure 1.
It will be understood that the embodiment What is claimed is:
l. A rotatable coupler for the transmission of alternating electric current between two balanced transmission lines rotating with respect to each other comprising two coaxial annular conductin plates flxedwith respect to each other, a number of m of parallel wire transmission lines feeding said two plates, one wire of each of said "122. transmissionlines being connected to one of said plates at points spaced substantially degrees from each other and the other wire of each of said m transmission lines being con two plates at connection points spaced a 7 degrees from each other,'the'number "n being any number neither a factor nor an integral multiple of said number m, said "12. parallel wire transmission lines being-fed in parallel bythe other of said two balanced transmission lines, the second pair of plates being positioned coaxially with thefirst pair and'sepa'ratedby a small distance from said 'fir'st' pair, and means for rotatably mounting one of said pairs of plates with respect to the other of said pairs of plates.
2. A rotatable coupler for the transmission of alternating electric current between two unbalanced transmission lines rotating with respect to eachother comprising two coaxial annularconducting plates fixed with respect to each'other, a number "m of parallel wire transmission lines feeding said two plates, one wire of eachof said 111. transmission lines being connected to one of said plates at points spaced substantially nected to the other of said plates at points having substantially the same radial positionsgas the corresponding points .of connection on said one plate, a line-balance converter feeding said fm transmission lines in parallel and being .fed by one of said two unbalanced transmission lines, third and fourth coaxial annular conducting plates fixed with respect to eachother and of substantially the same lateral dimensions as the first two plates. a; number n of parallel wire transmission lines feeding said third and fourth ing plates,- a plurality of connections between each conductor of said first'line andadifferent one of said conducting plates at various'angular points around the circumference of said plates, a second pair of coaxially disposed annular conducting plates ofsimilar dimension located in close proximity to the first pair and rotatable with respect thereto, and a connection between each conductor of the second line and the respective plates of the second pair at various angular positions around the circumference thereof, the connections to thes'econdpair of plates having a difierent angular relationship than those to the first pair of plates. I Q
8. A rotatable 'couplerfor the transmission of alternating current between a first transmission line and a second transmission line which is rotatable relative to said first transmission line comprising a first set of coaxially disposed annular conducting plates, one for each conductor of the first line, a plurality of connections betweeneach conductor of the first line and a difierent one of said conducting plates at various angular points around the circumference of the plates, a second set of coaxiallyf disposed annular conducting plates, of similar dimension and located inclose proximity to the said first set of plates, and rotatable with respect thereto, one. for each conductor of the second line, a connection between each conductor of the second line and a respective conducting plate of said second set of plates at various angular points around the circumference of the plates the connections to said second set of. plates having a different angular relationship than those to said first set of plates. v
9. In a rotary coupler system wherein-energy is coupled between two transmission line systems through a first and second set of -respectively capacitively coupled, coaxially I related plates where one of the plates of'ea'ch set are simultaneously rotatable with respect to the associated plate of each set, and where the impedance variations between the said-sets of plates varies appreciably with rotation of the rotatable plates thereof, the improvement comprising m transmission lines connectedin parallel'tooneef said .two transmission line systems; means connecting each set of commonly connected conductors, saidtransmission lines respectively to a different rotatable plate of said sets of plates, the commonly. connectedconductors connecting to the associatedplate at different points thereon surrounding the axis of rotation thereof, fin transmission lines connected in parallel to the other one of said transmission line systems, means connecting the sets of commonly connected. conductors of said latter transmission lines respectively, to, a different one of the other plates of said respective sets of plates, the commonly connected conductors connecting to the associated plate at'different points about the axis of rotation, of the associated rotatable plate, the number n being neither a factor nor an integer of said number ("1") ROBERT J. ADAMS. LEE R. DOBLER.
REFERENCES CITED The following references are of record in the file of this patentnf UNITED STATES PATE TS-
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US609692A US2602118A (en) | 1945-08-08 | 1945-08-08 | Capacitive rotatable coupler |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US609692A US2602118A (en) | 1945-08-08 | 1945-08-08 | Capacitive rotatable coupler |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2602118A true US2602118A (en) | 1952-07-01 |
Family
ID=24441909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US609692A Expired - Lifetime US2602118A (en) | 1945-08-08 | 1945-08-08 | Capacitive rotatable coupler |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2602118A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2894220A (en) * | 1955-03-30 | 1959-07-07 | Decca Record Co Ltd | Radar apparatus |
| US3013225A (en) * | 1958-08-27 | 1961-12-12 | Nippon Electric Co | Electrostatic coupling system |
| US3617607A (en) * | 1970-07-10 | 1971-11-02 | Us Air Force | Electromagnetic interference shield isolator |
| US3786376A (en) * | 1970-12-18 | 1974-01-15 | Ball Brothers Res Corp | Self-lubricated rotary joint |
| US3914715A (en) * | 1974-06-26 | 1975-10-21 | Texas Instruments Inc | Coaxial ring rotary joint |
| FR2523771A1 (en) * | 1982-03-19 | 1983-09-23 | Thomson Csf | Symmetric contact assembly for rotating 3-30 mhz RF antenna - comprises circular elements driven by motor and contacting ends of angularly spaced feeder lines |
| FR2628249A1 (en) * | 1988-03-07 | 1989-09-08 | Schlumberger Ind Sa | ROTARY ELECTRIC COUPLING DEVICE FOR A RECORDER WITH A ROTATING HEAD AND A RECORDER PROVIDED WITH SUCH A DEVICE |
| EP0372179A1 (en) * | 1988-11-07 | 1990-06-13 | Balzers Aktiengesellschaft | Method of procuring high-frequency energy, and its use |
| EP0854470A1 (en) * | 1997-01-21 | 1998-07-22 | Enertec S.A. | Magnetic tape recorder/player with a capacitive coupling devicef |
| US20090102313A1 (en) * | 2007-09-20 | 2009-04-23 | Joseph Newhall West | Transmission Lines Applied to Contact Free Slip Rings |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2256538A (en) * | 1939-10-10 | 1941-09-23 | Mackay Radio & Telegraph Co | Phase shifting device and circuits incorporating the same |
| US2292791A (en) * | 1940-08-03 | 1942-08-11 | Morrill P Mims | Directional antenna system |
| US2320124A (en) * | 1941-01-18 | 1943-05-25 | Colonial Radio Corp | Radio receiver for horizontally polarized waves |
| US2401344A (en) * | 1940-06-14 | 1946-06-04 | Gen Electric Co Ltd | High-frequency electric transmission system |
| US2402603A (en) * | 1944-03-13 | 1946-06-25 | Standard Telephones Cables Ltd | Distributor |
| US2402540A (en) * | 1941-08-26 | 1946-06-25 | Gen Electric Co Ltd | Electrical apparatus adapted to operate at very high frequencies |
| US2405616A (en) * | 1943-07-07 | 1946-08-13 | Silver Walter | Antenna coupling |
-
1945
- 1945-08-08 US US609692A patent/US2602118A/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2256538A (en) * | 1939-10-10 | 1941-09-23 | Mackay Radio & Telegraph Co | Phase shifting device and circuits incorporating the same |
| US2401344A (en) * | 1940-06-14 | 1946-06-04 | Gen Electric Co Ltd | High-frequency electric transmission system |
| US2292791A (en) * | 1940-08-03 | 1942-08-11 | Morrill P Mims | Directional antenna system |
| US2320124A (en) * | 1941-01-18 | 1943-05-25 | Colonial Radio Corp | Radio receiver for horizontally polarized waves |
| US2402540A (en) * | 1941-08-26 | 1946-06-25 | Gen Electric Co Ltd | Electrical apparatus adapted to operate at very high frequencies |
| US2405616A (en) * | 1943-07-07 | 1946-08-13 | Silver Walter | Antenna coupling |
| US2402603A (en) * | 1944-03-13 | 1946-06-25 | Standard Telephones Cables Ltd | Distributor |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2894220A (en) * | 1955-03-30 | 1959-07-07 | Decca Record Co Ltd | Radar apparatus |
| US3013225A (en) * | 1958-08-27 | 1961-12-12 | Nippon Electric Co | Electrostatic coupling system |
| US3617607A (en) * | 1970-07-10 | 1971-11-02 | Us Air Force | Electromagnetic interference shield isolator |
| US3786376A (en) * | 1970-12-18 | 1974-01-15 | Ball Brothers Res Corp | Self-lubricated rotary joint |
| US3914715A (en) * | 1974-06-26 | 1975-10-21 | Texas Instruments Inc | Coaxial ring rotary joint |
| FR2523771A1 (en) * | 1982-03-19 | 1983-09-23 | Thomson Csf | Symmetric contact assembly for rotating 3-30 mhz RF antenna - comprises circular elements driven by motor and contacting ends of angularly spaced feeder lines |
| FR2628249A1 (en) * | 1988-03-07 | 1989-09-08 | Schlumberger Ind Sa | ROTARY ELECTRIC COUPLING DEVICE FOR A RECORDER WITH A ROTATING HEAD AND A RECORDER PROVIDED WITH SUCH A DEVICE |
| EP0332520A1 (en) * | 1988-03-07 | 1989-09-13 | Schlumberger Industries | Rotating head recorder provided with a rotatable electrical coupling device |
| EP0372179A1 (en) * | 1988-11-07 | 1990-06-13 | Balzers Aktiengesellschaft | Method of procuring high-frequency energy, and its use |
| US5064522A (en) * | 1988-11-07 | 1991-11-12 | Balzers Aktiengesellschaft | Feed through for application of hf energy |
| EP0854470A1 (en) * | 1997-01-21 | 1998-07-22 | Enertec S.A. | Magnetic tape recorder/player with a capacitive coupling devicef |
| FR2758643A1 (en) * | 1997-01-21 | 1998-07-24 | Schlumberger Ind Sa | MAGNETIC BAND RECORDER / PLAYER COMPRISING A CAPACITIVE COUPLING DEVICE |
| US6091588A (en) * | 1997-01-21 | 2000-07-18 | Enertec | Magnetic tape recorder having a capacitive coupling device in the form of fixed and mobile rings or ring segments |
| US20090102313A1 (en) * | 2007-09-20 | 2009-04-23 | Joseph Newhall West | Transmission Lines Applied to Contact Free Slip Rings |
| US8138849B2 (en) * | 2007-09-20 | 2012-03-20 | Voxis, Inc. | Transmission lines applied to contact free slip rings |
| US9136912B2 (en) | 2007-09-20 | 2015-09-15 | Voxis, Inc. | Transmission lines applied to contact free slip rings |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2602118A (en) | Capacitive rotatable coupler | |
| US2405437A (en) | Impedance matching transformer | |
| US2519933A (en) | Rotatable joint for coaxial cables | |
| US2446982A (en) | Apparatus for broad-band radio transmission | |
| US2420967A (en) | Turnstile antenna | |
| US2245693A (en) | Radial radiating system for shortwave communication | |
| US2660674A (en) | Slotted antenna system | |
| US2275030A (en) | Turnstile antenna | |
| GB924145A (en) | Improvements in or relating to antenna structure | |
| US2453759A (en) | Tapered union for concentric conductor lines | |
| US2318237A (en) | Antenna feed system | |
| US3143717A (en) | Ring and brush rotary electric coupling | |
| US2341408A (en) | Antenna feed system | |
| US2473328A (en) | Line balance converter | |
| US2258406A (en) | Wide band antenna | |
| US2404399A (en) | Adjustable transmission line | |
| US2831169A (en) | Microwave line with variable electrical length | |
| US2368286A (en) | Antenna system | |
| US2503952A (en) | Traveling wave antenna | |
| US2401572A (en) | Rotating joint for parallel wire transmission lines | |
| US2232592A (en) | Modulation system | |
| US2457127A (en) | Antenna system | |
| US2231839A (en) | Junction between single and pushpull lines | |
| US2243136A (en) | Wide band antenna system | |
| US2426236A (en) | Coupling system |