Патент USA US2409641код для вставки
Oct 22, 1946. > ‘ ' F,'_|, MQLES ‘ ' 2,409,640 POWER CABLE magma FREQUENCY OSCILLATORS I Filed Sept.- 18. 1942' ‘ . ' v5/ FT9».1. ' so a8 . E as 4 2 2/ 1~2 :' 12 § 25* " .26 22 v /6 l5 /4' E _ 34 ,9 a7 \ _/_/ ‘ "" '24 2 21 = 5 ' 28 5' 3 2s i 5 >50 I3 2o 55 33 4 32 40 53%| 53 m 5/ l_2 55 50 E 55 COPPER Inventor: Frank J. Moles, by I JAM His Attorney. Patented Oct. 22, 1946 2,409,640 UNITED STATES PATENT OFFICE 2,409,640 POWER CABLE FOR HIGH-FREQUENCY OSCILLATORS Frank J. Moles, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application September 18, 1942, Serial No. 458,821 ' 4 Claims. (01. 178-44) 2 1 My invention relates to cables and particularly and as a The sion to cables adapted for use in the power supply cir cuits of short wave electron discharge apparatus, such as oscillators, ampli?ers, and the like. It is an object of my invention to provide an improved cable which has both high attenuation at short wave length and has low distributed the concentric transmission line 25 serving handle to adjust the position of the ring 23. coupling loop 26, at the end of the transmis line 25, extends into the cavity between the conductors l5 and I6 and provides a means for abstracting high frequency energy from this cav ity when it is in excited condition. The extremities of the conductors l4, l5 and I6 which are remote from the base part 2|, are capacity. Another object of my invention is to provide a cable which may be manufactured at a low cost, 10 provided respectively with the ?nger members 21, 28 and 29 for engagement with the metal disks which is easily constructed from available mate rials and may be applied to existing high fre quency oscillators. The features of my invention which I believe to 3B—32, disk 36 being connected to the anode l9, disk 3| to the control electrode l8 and disk 32 to the cathode 20. The insulators 33 of any be novel are set forth with particularity in the 15 suitable insulating material, such as glass, pro vide means for insulating‘the respective elements appended claims. My invention itself, however, of the device IT and holding the disks 3ll--32 in together with further objects and advantages spaced relation. The metal ?ngers 21 are sepa thereof, may best be understood by reference to rated from the conductor 16 by a sleeve 34 of any the following description taken in connection with the accompanying drawing in which Fig. 1 shows 20 suitable insulating material. The cathode 29 is indirectly heated by the ?la an ultra high frequency oscillator employing the ment 35, current for ?lament 35 being supplied cable of my invention and Fig. 2 shows a pre through the inner conductors of the cables :2 ferred embodiment of my high frequency cable. and i3. Operating potential for the anode I9 is Referring to the drawing, I have illustrated my improved cable as employed in the power supply 25 supplied over the inner conductor of the cable I | conductively connected to the rod-like member circuits of an ultra high frequency oscillator l9 38 having ?ngers 31- for engagement with the which is shown to be of the resonant cavity type anode [9. The insulating sleeve 38 is provided and to which operating potentials are supplied to insulate the end member 2| from the high by means of the power leads H—|3. potential present on the rod member 36. . Since the particular form of the ultra high fre End member 39, engaging the bottom of tube quency oscillator [0 forms no part of the present H, is provided to securely hold tube IT in a fixed invention, its structure and operation will not be position in the oscillator and to adjust the pres described in detail. Brie?y, the cavity oscillator sure of ?ngers 2'l—29 on disk 3B—32. Insulator i0 employs three telescoped and radially sepa 40 of rubber, or any similar material, prevents rated conductors ill-J6 which de?ne concentric lateral displacement of tube H. The cavity res space-resonant cavities between them. These are onator and discharge device described above are used in combination with an electronic tube I‘! not my invention and are fully described and having its control electrode l8 coupled to the claimed in copending Beggs application Serial intermediate conductor l5 and its anode l9 and cathode 26 coupled respectively to the remaining 40 No. 436,633, ?led March 28, l942,,and copending Jensen et al. application Serial No. 448,206, ?led June 24, 1942. In the operation of the oscillator thus far de either of metal or of insulating material. By vir scribed when the cathode 20 is heated by the tue of their'mutual spacing, the conductors pro vide, in effect, a pair of concentric transmission 45 ?lament 35 and high positive potential is sup— plied to the anode I9, since the grid and cathode line sections, each of which by proper termina operate at the same potential for unidirectional tion can be made to function as an oscillatory cir current, current flows between the anode l9 and cuit having a, particular resonant frequency. The the cathode 20. Assuming proper tuning of the movable short-circuiting rings 22 and 23 are pro vided for adjusting the length of these lines. 50 inner and outer transmission line sections, that is by proper adjustment of the shorting rings 22 Annular metal short-circuiting rings 22 and 23, and 23, high frequency oscillations may be de each of which contacts a pair of the conductors veloped. The sleeve of insulation 34 serves to l4—l6, are provided to adjust the length of the isolate the conductor [6 from the high unidirec transmission line in question, the handles 24 be ing provided to adjust the position of the ring 22 55 tional potentials present on the anode I9 and. conductors. At their upper ends the conductors are secured to a common base 2|, which may be 2,409,640 3 4 also serves capacitively to couple conductor l6 and the anode IQ for high frequency voltages. As mentioned previously, the control electrode It decibels per inch and a distributed capacity of about 12 micromicrofarads per foot. Thus, a ca ble constructed as above described is well adapted for attenuating such high frequencies and at the same time keeping a relatively low distributed capacity on the power lead. It is apparent that various modi?cations of the above-described cable may be made. Thus, where a ?exible cable is not required, a rigid wire may and cathode ‘it are operated at the same poten~ tial for unidirectional voltages and for high frequency currents at a potential determined by the tuning of the transmission line comprising the conductors M and I5. In the operation of an oscillator of this type, considerable difficulty has been experienced in 10 be used as the conductor 55 and a copper tube con?ning the high frequency energy to the as the sheath 5!. Also, any ?nely divided metal, resonant cavities of the oscillator and the oon~ other than steel wool, having a relatively high centric transmission line 25 and in preventing this resistance as compared With the resistance of high frequency ‘energy from ?owing over the conductors 50 and 5|, may be used as the ?lling power leads ll-IS. Such leakage of high fre material 52. In particular, stainless steel has the quency energy results both in the occurrence of qualities desire for material 52. Thus, while I undesirable currents of high frequency in the have shown a particular embodiment of my in power supply and any outside measuring circuits vention, it will of course be understood that I do and in a reduced output and efficiency of the not wish to be limited thereto since various mod oscillator. 20 i?cations may be made and I contemplate by the In order to prevent the leakage of high fre appended claims to cover any such modi?cations quency energy over the power leads supplying as fall within the true spirit and scope of my low frequency energy to an oscillator, such as invention. the oscillator in, in accordance with my inven What I claim as new and desire to secure by tion the cable illustrated in Fig, 2 is provided. Letters Patent of the United States is: This cable comprises the inner conductor 55 and l. A ?lter for removing high frequency oscil the outer conductor or sheath 5|, both conduc lations from a power lead comprising a conduc tors being preferably of a low resistance mate tive sheath surrounding said lead and spaced rial, such as copper. As shown in Fig. 2, the therefrom, a mass of metal ?bers having a rela outer conductor 5| is in spaced relation with 30 tively high resistance disposed in the space be respect to the inner conductor 5|! and the space tween said lead and said sheath, and means for between these conductors is ?lled with a mass insulatingr said metal from said lead and said of ?nely divided, or ?brous, conductive material sheath whereby power currents of low frequency of relatively high resistance, such as steel wool. may be transmitted over said power lead without The high resistance material 52 is insulated from ' attenuation by said ?lter while high frequency the conductor 50 by the insulating sleeve 53 and currents transmitted over said power lead are from the sheath 5|, by the insulating sleeve 54. In the use of a cable of the type shown in Fig. 2 with power leads connected to a high frequen cy oscillator, the inner conductor 50 provides a low resistance path for the power current, while the ?nely divided metal ?bers 52 surrounding the insulating conductor 50 act as a large number of mutually coupled circuits having high resistance to the high frequency currents ?owing in them. This material 52 of the cable thus dissipates the highly attenuated. 2. In combination, a low resistance conductor, a low resistance sheath surrounding said conduc tor and in spaced relation therewith, a continu ous layer of ?nely divided metal of relatively high resistance disposed in the space between said conductor and said sheath, and means insulating said metal from said conductor and said sheath whereby power currents of low frequency may be transmitted over said conductor without attenu high frequency energy which otherwise would es ation while high frequency currents transmitted cape to outside measuring circuits and the po over said conductor are highly attenuated. tential source. The insulating sleeves 53 and 54 3. A cable for supplying low frequency cur maintain a relatively low distributed capacity in 50 rents to a high frequency oscillator comprising a the cable. low resistance conductor, a conductive sheath In connecting the cable II to the oscillator Hi, surrounding said conductor and in spaced rela_ the inner conductor '59 is directly connected to tion therewith, and a ?lling of steel wool disposed the rod member 35, while the outer sheath 5| is in the space between said sheath and said con secured to the end member 2| in any suitable ductor, said steel wool being insulated from said manner, such as for example, by soldering. Sim sheath and said conductor. ilarly, in connecting the cables !2 and I3 to the A ?lter for removing high frequency oscil leads of the ?lament 35 through suitable open lations from a power lead operating at a poten ings in the end member 39, the outer sheath 5| is tial difference with respect to ground compris secured to the end member 39 While the insu 60 ing a grounded conductive sheath surrounding lating sleeve 53 serves to insulate conductor 58 said lead and spaced therefrom, a compact mass from the end member. of ?bers of a relatively high resistance metal dis In operation it has been found that only a rel posed in the space between said lead and said atively short length of cable is needed to get de sheath, and means for insulating said metal fi sired attenuation at very high frequencies, Thus, bers from both said lead and said sheath where with an oscillator operating at 3000 megacycles, by power currents of low frequency may be trans a cable constructed of a fabric insulated 40-mil mitted over said power load without attenuation wire as the conductor 50, a it; inch layer of steel wool as the ?nely divided metal 52, an impreg nated cambric as the insulating sleeve 54, and a 1/; inch copper braid as the outer conductor 5| was observed to have an attenuation of about 3 by said ?lter while high frequency currents trans mitted over said power lead are highly attenu ated. FRANK J. MOLES.