US3590313A - Dither tuned microwave tube with corrected tuner resolver output - Google Patents

Dither tuned microwave tube with corrected tuner resolver output Download PDF

Info

Publication number
US3590313A
US3590313A US5025A US3590313DA US3590313A US 3590313 A US3590313 A US 3590313A US 5025 A US5025 A US 5025A US 3590313D A US3590313D A US 3590313DA US 3590313 A US3590313 A US 3590313A
Authority
US
United States
Prior art keywords
tuning
resolver
tube
pair
gears
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
Application number
US5025A
Other languages
English (en)
Inventor
Richard C Stoke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Varian Medical Systems Inc
Original Assignee
Varian Associates Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Varian Associates Inc filed Critical Varian Associates Inc
Application granted granted Critical
Publication of US3590313A publication Critical patent/US3590313A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J23/18—Resonators
    • H01J23/20—Cavity resonators; Adjustment or tuning thereof
    • H01J23/207—Tuning of single resonator
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00—Machine element or mechanism
    • Y10T74/19—Gearing
    • Y10T74/1954—Eccentric driving shaft and axle

Definitions

  • dither tuned microwave tubes such as coaxial magnetrons
  • a motor for driving a Crankshaft which cranks a tuning plunger to and fro within the microwave tube for dither tuning the output of the microwave tube.
  • a resolver has been coupled to the crankshaft for deriving an electrical output signal corresponding to the instantaneous frequency of the dither tuned tube.
  • Typical examples of such dither tuned tubes are disclosed in US. Pat. Nos. 3,414,761 issued Dec. 3, 1968; 3,441,794 issued Apr.
  • the resolver output signal is typically fed to a voltage tunable local oscillator in a radar receiver such that the local oscillator frequency is varied in accordance with variations in the instantaneous frequency output of the dither tuned tube which is typically the transmitter tube.
  • Dither tuning the transmitter tube and employing the output of the resolver for tracking the local oscillator frequency in the receiver produces a substantial gain in the receiver and greatly improves the signal to noise ratio of the radar. For example, if the receiver local oscillator frequency variations track the instantaneous frequency variations of the dithered tube within a percent error, an equivalent 4 db.
  • the resolver tracking error was limited by the nonlinearity of the tuning characteristic of the microwave tube. In other words, over the range of physical displacement of the tuning plunger within the microwave tube, a given increment of tuner displacement at one end of the tuner movement produced a given frequency deviation, whereas an equivalent displacement of the tuning member at the other end of the range of tuner displacement produced a substantially different frequency deviation. It would be desirable to provide a dither tuned tube in which the resolver output tracked the instantaneous frequency of the tube to within an error of one-half a percent.
  • the principal object of the present invention is the provision of an improved dither tuned microwave tube having a corrected tuner resolver output.
  • One feature of the present invention is the provision in a dither tuned microwave tube employing a resolver operatively interconnected with the dither tuning structure by means of a gear train of a pair of eccentric meshing bears for compensating the resolver output for the nonlinear tuning characteristic of the tuning structure, whereby the resolver output tracks the frequency deviation of the tube with a high degree of accuracy.
  • Another feature of the present invention is the same as the first feature wherein the pair of eccentric compensating gears are circular gears mounted eccentrically on a pair of shafts, one of the gears being a driver gear and the other being a driven gear, whereby the eccentric gear compensator structure is substantially simplified for ease of manufacture.
  • gear train includes a pair of concentric outer and inner separately rotatable drive shafts, the outer shaft forming a crankshaft for the dither tuning mechanism and the inner drive shaft being coupled to the resolver for driving the resolver at the same instantaneous angular velocity as the inner drive shaft.
  • Another feature of the present invention is the same as the first feature wherein the pair of eccentric meshing gears are noncircular gears.
  • FIG. 1 is a plot of tuner displacement d versus output frequencyfof a dither tuned microwave tube and showing a nonlinear tuning curve
  • FIG. 2 is a plot of resolver output voltage V and output frequency f versus angular displacement 0 of the dither tuning drive shaft
  • FIG. 3 is a schematic diagram. of a pair of twin eccentric gears employed for compensating for the nonlinear tuning characteristic according to the present invention
  • FIG. 4 is a schematic line diagram of an alternative pair of eccentric meshing gears for compensating for a nonlinear tuning characteristic according to the present invention
  • FIG. 5 is a schematic block diagram for a dither tuned tube incorporating eccentric gear compensation of the present invention
  • FIG. 6 is a schematic block diagram for an alternative eccentric gear compensated dither tuned system of the present invention.
  • FIG. 7 is a fragmentaRy schematic line diagram depicting twin eccentric meshing gears employed in the compensator of the present invention.
  • FIG. 8 is a fragmentaryview, partly in section, of a dither tuned magnetron incorporating features of the present invention.
  • FIG. 9 is a sectional view of the structure of FIG. 8 taken along line 9-9 in the direction of the arrows.
  • FIG. I there is shown a typical tuning curve 1 for a microwave tube, such as a dither tunable coaxial magnetron of the type described and disclosed in the aforecited patents and applications.
  • the tuning element of the tube is displaced, in the manner as depicted by sinusoidal curve 2 oscillating between displacement d, and d from a midposition d in accordance with a drive shaft angular displacement 0, the output frequency of the tube varies from a low frequencyf to a maximum frequency f
  • the midpoint position d does not correspond to the center frequency f of the dither tuned band.
  • the output frequency f will have a nonsinusoidal variation with angular displacement of the drive shaft as depicted by curve 4 in FIG. 2.
  • the drive shaft drives a resolver having an output voltage which is a sinusoidal variation of the angular displacement 0, as depicted by the solid curve 3 of FIG. 2, it will be seen that the output frequency f lags the resolver output voltage V at the position by an angular displacement of 211 leads the voltage curve 3 at the 270 position by 2a and that this is a near maximum lag or lead displacement.
  • the drive shaft drives a resolver having an output voltage which is a sinusoidal variation of the angular displacement 0
  • the output frequency f lags the resolver output voltage V at the position by an angular displacement of 211 leads the voltage curve 3 at the 270 position by 2a and that this is a near maximum lag or lead displacement.
  • the output frequency f lags the resolver output voltage V at the position by an angular displacement of 211 leads the voltage curve 3 at the
  • a pair of eccentric gears such as those depicted in FIG. 3 or 4, are employed in the tuner drive gear train coupling the dither tuner resolver and motor in the manner as schematically indicated in FIGS. 5 or 6 to correct for the nonlinearity of the tuning curve 1 in order to reduce the tracking error to on the order of one-half of a percent or better.
  • a pair of eccentric gears is defined to include a pair of circular gears eccentrically mounted on a pair of drive shafts, as indicated in FIG. 3, as well as a pair of elliptical or noncircular gears 9 and 10 centrally or eccentrically mounted on a pair of drive shafts 11 and 12.
  • the eccentric meshing gears have the characteristic that starting from a reference point the driven shaft as driven from the driver's shaft via the driver gear and driven gear can be caused to lag behind the driver shaft for the first 180 of rotation reaching a maximum lag at approximately 90 of rotation and from 180 to 360 to lead the driver shaft by a maximum lead angle occurring near the 270. This is the compensation required to compensate for the nonlinear tuning curve 1 of FIG. 1.
  • the tuner system includes a resolver 13 driven from the output shaft of a motor 14 for producing a resolver output voltage curve as shown by curve 3 of FIG. 2.
  • the output shaft of the motor 14 also drives the dither tuner 15 via the intermediary of an eccentric gear compensator 16 of the type generally shown in FIG. 3.
  • the dither tuner drive shaft needs to be driven in such a manner that a given angular displacement of the driver gear produces a correspondingly greater angular displacement of the dither tuner drive shaft.
  • the output shaft of the motor drives shaft 7 of FIG. 3 which in turn drives driver gear 5 which meshes with driven gear 6 which in turn drives dither tuner shaft 8.
  • a similar compensating result can be obtained by the eccentric gear compensator 16' of FIG. 4 where a given angular displacement of the driver shaft 11 produces a correspondingly increased angular displacement of the driven output shaft 12 for the first 90 of rotation from the position as shown.
  • the angular lead achieved during the first 90 diminishes to O at 180 of rotation and then for the next 90 of rotation from 180 to 270 the driven shaft angular rotation lags the equivalent rotation of the driver shaft and in the rotation from 270 to 360 this lag decreases to 0.
  • FIG. 6 there is shown an alternative embodiment of the present invention wherein the eccentric gear compensator 16 is disposed between the motor and the resolver 13 causing the resolver output to be corrected to the output tuning characteristic of the dither tuner 15.
  • the compensator 16 is arranged such that for the first 90 of rotation of the output shaft of the motor as applied to the input of the compensator 16 the output shaft of the compensator reaches a maximum lag of 201", such lag then decreasing to 0 at the 180 position of the input shaft to the compensator 16.
  • the compensator 16 of FIGS. 3 and 4 is merely reversed such that the driven gear becomes the driver gear and the driver gear becomes the driven gear.
  • the motor drives shaft 8 of FIG. 3 and shaft 7 drives the resolver 13
  • the motor drives shaft 12 and shaft 11 drives the resolver shaft.
  • the amount of angular lead or lag required is first determined by plotting the output frequency of the tube as a function of the angular displacement 0 of the dither tuner crankshaft. It is assumed that the resultant curve is curve 4 of FIG. 2. Assuming that the resolver output is linear as a function of its shaft rotation, which will be the case to a very high degree, a sinusoidal curve 3 is plotted for the resolver output,
  • the gears 5 and 6 are circular having centers C, and C for driven gear 6 and driver gear 5, respectively.
  • the gears are eccentrically mounted on drive shafts with the axes of the drive shafts 7 and 8 intersecting the gears 5 and 6 at E, and 15,, respectively.
  • the center of the shafts are displaced from the center of the gears by an equal amount of eccentricity e.
  • the axes of the shafts are displaced by D.
  • the vane resonators are carried at their outer edges from a cylindrical anode wall 26 forming a common wall of the resonator 23 and the vane resonator system 24.
  • An array of longitudinally directed coupling slots 27 are provided communicating through the common wall 26 with alternate vane resonators for locking the 11' mode of oscillation of the vane resonator system to a circular electric mode in the coaxial cavity 23.
  • the upper end wall of the cavity 23 is axially movable for tuning the resonant frequency of the resonator 23 and thus the frequency of the 11' mode and the output frequency of the tube.
  • Movable end wall 28 is carried from the dependent legs 29 of a spider structure 31.
  • the body portion 31 of the spider is an annular disc sealed to the body of the tube via a pair of bellows 32 and 33.
  • the spider 31 is axially translatable via a piston rod 34 which is affixed at its lower extremity via a ball joint to an inner cylindrical slide 35 which is affixed at its inner end to the inner end 36 of an outer cylindrical slide bearing 37 which in turn is affixed to the body of the spider 31.
  • a fixed cylindrical slide bearing 38 is affixed to the body of the tube for guiding the axially translatable slides 35 and 37.
  • the piston rod 34 includes a yoke portion 39 containing a ball bearing assembly 41 which rides on an eccentric portion 42 of a transversely directed hollow cylindrical crankshaft 43.
  • a second drive shaft 44 is coaxially mounted within the crankshaft 43 and is affixed at one end to the resolver 13 via a coupling structure 45.
  • the motor 14 is affixed to a tuner housing structure 46 which houses the crankshaft 43, and drive shaft 44 and a gear train 47 which drives shafts 43 and 44 from the motor 14.
  • the gear train 47 includes a gear 48 (see FIG. 9) affixed to the output shaft of the motor 14 which in turn drives an idler gear 49 which in turn drives a main drive gear 51 for driving a power drive shaft 52 at a substantially reduced angular velocity compared to the output drive of the motor 14. More particularly, the gears 48, 49 and 51 serve to reduce the angu lar velocity of the drive shaft from 10,000 r.p.m. to approximately In the embodiment of the invention schematically indicated in FIG. 5 where the dither tuning characteristic 4 is compensated to bring it into conformance with the resolver characteristic 3, the eccentric compensator gears 16 comprise a pair of twin eccentric gears 53 and 54, gear 53 serving to drive gear 54 from drive shaft 52.
  • the resolver drive shaft 44 is driven from the power drive shaft 52 via a pair of twin drive gears 55 and 56.
  • the driver gears 55 and 56 are selected to drive the resolver shaft at the same average angular velocity as the angular velocity of the tuner crankshaft 43.
  • the twin eccentric compensator gears 53 and 54 are chosen and arranged in the manner as previously indicated with regard to FIGS. 7 and 2 above.
  • gears 55 and 56 are made to comprise twin eccentric gears, in the manner as above described, while gears 53 and 54, in this case, are selected merely to drive the tuner crankshaft at the same average angular velocity as that of the resolver drive shaft 44.
  • a brake 58 is affixed to the motor 14 for holding the position of the tuner and its associated gear train in a lockedposition for selectively operating the tube in a fixed tuned manner
  • tuner and resolver compensating arrangement of the present invention has been described as it is employed for compensating the nonlinear tuning effects of a coaxial magnetron, the invention is equally applicable to other types of tunable microwave tubes such as klystrons, triodes, and the like.
  • microwave circuit means for determining the operating frequency of the microwave tube, tuner means movable within the region of said circuit means for tuning said microwave circuit and thus the operating frequency of the tube, said tuning means having a nonlinear displacement versus tuning characteristic, means for moving said movable tuning means to and fro to dither tune the tube, resolver means for deriving an output representative of the instantaneous operating frequency of the tube, gear train means operatively interconnecting said resolver means and said dithering means for synchronizing the output of said resolver means with movement of said tuning means, THE IMPROVEMENT WHEREIN, said gear train means includes a pair of eccentric meshing gears for reducing error between the resolver output and the instantaneous frequency of the tube.
  • said gear train includes a pair of concentric outer and inner separately rotatable drive shafts, said outer drive shaft having an eccentric portion forming a crankshaft for said dither tuning means and said inner drive shaft being coupled to said resolver means at the same average angular velocity as said outer drive shaft.
  • microwave circuit means includes a circular cavity resonator and said tuning means includes a circular tunin member axially translatable within said resonator for tuning t e operating frequency of the tube.

Landscapes

  • Microwave Tubes (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
US5025A 1970-01-22 1970-01-22 Dither tuned microwave tube with corrected tuner resolver output Expired - Lifetime US3590313A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US502570A 1970-01-22 1970-01-22

Publications (1)

Publication Number Publication Date
US3590313A true US3590313A (en) 1971-06-29

Family

ID=21713744

Family Applications (1)

Application Number Title Priority Date Filing Date
US5025A Expired - Lifetime US3590313A (en) 1970-01-22 1970-01-22 Dither tuned microwave tube with corrected tuner resolver output

Country Status (5)

Country Link
US (1) US3590313A (enrdf_load_stackoverflow)
JP (1) JPS5546017B1 (enrdf_load_stackoverflow)
CA (1) CA928427A (enrdf_load_stackoverflow)
FR (1) FR2075786A5 (enrdf_load_stackoverflow)
GB (1) GB1296303A (enrdf_load_stackoverflow)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2165692A5 (enrdf_load_stackoverflow) * 1971-12-18 1973-08-03 Lucas Industries Ltd
US3852638A (en) * 1974-03-14 1974-12-03 Varian Associates Dither tuned microwave tube
US3869638A (en) * 1973-11-02 1975-03-04 Varian Associates Triangular dither-tuned microwave tube
US3870923A (en) * 1972-12-29 1975-03-11 Thomson Csf Magnetron with an improved tuning mechanism
US3876903A (en) * 1974-03-22 1975-04-08 Varian Associates Dither tuned microwave tube
US4084509A (en) * 1976-09-20 1978-04-18 Package Machinery Company Apparatus for printing on an advancing web
DE2903881A1 (de) * 1978-02-02 1979-08-09 Sits Soc It Telecom Siemens Einrichtung zur linearen abstimmung von mikrowellenroehren
US4247828A (en) * 1978-07-03 1981-01-27 Societa Italiana Telecomunicazioni Siemens S.P.A. Reciprocating piston tuning mechanism for a microwave oscillator
US4313091A (en) * 1979-02-13 1982-01-26 Societa Italiana Telecomunicazioni Siemens S.P.A. Crankshaft tuning mechanisms for microwave oscillators
DE3336997A1 (de) * 1982-10-19 1984-04-19 Varian Associates, Inc., 94303 Palo Alto, Calif. Geraet mit resonanzhohlraum, insbesondere frequenzbewegliches magnetron, mit hoehenkompensation
US4613788A (en) * 1983-04-29 1986-09-23 U.S. Philips Corporation Arrangement in a tunable high frequency transmitter tube
EP0543790A1 (en) * 1991-11-19 1993-05-26 Hughes Aircraft Company Stabilized telephony combiner
US5977903A (en) * 1997-07-15 1999-11-02 Mitsubishi Denki Kabushiki Kaisha Scanning mechanism for vehicle- mounted radar
US20170219049A1 (en) * 2016-02-03 2017-08-03 Konica Minolta, Inc. Driving Device, Fixing Device and Image Forming Apparatus

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2992361A (en) * 1948-01-05 1961-07-11 Robert F Rychlik Rapidly tunable magnetron
US3154739A (en) * 1962-07-09 1964-10-27 Motorola Inc Automatic frequency control system for high frequency transmitters
US3441795A (en) * 1966-06-24 1969-04-29 Sfd Lab Inc Ditherable and tunable microwave tube having a dithered tuner actuator of fixed length
US3441794A (en) * 1966-06-15 1969-04-29 Varian Associates Dither-tuned tunable microwave tube apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2992361A (en) * 1948-01-05 1961-07-11 Robert F Rychlik Rapidly tunable magnetron
US3154739A (en) * 1962-07-09 1964-10-27 Motorola Inc Automatic frequency control system for high frequency transmitters
US3441794A (en) * 1966-06-15 1969-04-29 Varian Associates Dither-tuned tunable microwave tube apparatus
US3441795A (en) * 1966-06-24 1969-04-29 Sfd Lab Inc Ditherable and tunable microwave tube having a dithered tuner actuator of fixed length

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2165692A5 (enrdf_load_stackoverflow) * 1971-12-18 1973-08-03 Lucas Industries Ltd
US3870923A (en) * 1972-12-29 1975-03-11 Thomson Csf Magnetron with an improved tuning mechanism
US3869638A (en) * 1973-11-02 1975-03-04 Varian Associates Triangular dither-tuned microwave tube
US3852638A (en) * 1974-03-14 1974-12-03 Varian Associates Dither tuned microwave tube
US3876903A (en) * 1974-03-22 1975-04-08 Varian Associates Dither tuned microwave tube
US4084509A (en) * 1976-09-20 1978-04-18 Package Machinery Company Apparatus for printing on an advancing web
DE2903881A1 (de) * 1978-02-02 1979-08-09 Sits Soc It Telecom Siemens Einrichtung zur linearen abstimmung von mikrowellenroehren
US4234855A (en) * 1978-02-02 1980-11-18 Societa Italiana Telecomunicazioni Siemens S.P.A. System for linearly tuning a microwave oscillator
US4247828A (en) * 1978-07-03 1981-01-27 Societa Italiana Telecomunicazioni Siemens S.P.A. Reciprocating piston tuning mechanism for a microwave oscillator
US4313091A (en) * 1979-02-13 1982-01-26 Societa Italiana Telecomunicazioni Siemens S.P.A. Crankshaft tuning mechanisms for microwave oscillators
DE3336997A1 (de) * 1982-10-19 1984-04-19 Varian Associates, Inc., 94303 Palo Alto, Calif. Geraet mit resonanzhohlraum, insbesondere frequenzbewegliches magnetron, mit hoehenkompensation
US4527094A (en) * 1982-10-19 1985-07-02 Varian Associates, Inc. Altitude compensation for frequency agile magnetron
US4613788A (en) * 1983-04-29 1986-09-23 U.S. Philips Corporation Arrangement in a tunable high frequency transmitter tube
EP0543790A1 (en) * 1991-11-19 1993-05-26 Hughes Aircraft Company Stabilized telephony combiner
US5977903A (en) * 1997-07-15 1999-11-02 Mitsubishi Denki Kabushiki Kaisha Scanning mechanism for vehicle- mounted radar
US20170219049A1 (en) * 2016-02-03 2017-08-03 Konica Minolta, Inc. Driving Device, Fixing Device and Image Forming Apparatus
US10161478B2 (en) * 2016-02-03 2018-12-25 Konica Minolta, Inc. Driving device, fixing device and image forming apparatus

Also Published As

Publication number Publication date
CA928427A (en) 1973-06-12
JPS5546017B1 (enrdf_load_stackoverflow) 1980-11-20
FR2075786A5 (enrdf_load_stackoverflow) 1971-10-08
GB1296303A (enrdf_load_stackoverflow) 1972-11-15

Similar Documents

Publication Publication Date Title
US3590313A (en) Dither tuned microwave tube with corrected tuner resolver output
US3714592A (en) Network for pulling a microwave generator to the frequency of its resonant load
US2753481A (en) Travelling wave oscillators
GB1133429A (en) Ditherable and tunable microwave tube having a dithered tuner actuator of fixed length
US3441794A (en) Dither-tuned tunable microwave tube apparatus
US3069590A (en) Electron tube apparatus
US2425738A (en) Tunable high-frequency electron tube structure
US4209755A (en) Tunable oscillator comprising dual-cavity klystron
US3414761A (en) Dither tuner for a coaxial magnetron
US2623194A (en) Tuner for high-frequency tubes
GB1095717A (en) Tunable microwave electron discharge devices
US4234855A (en) System for linearly tuning a microwave oscillator
US2644908A (en) Microwave frequency cavity resonator structure
US3202944A (en) Cavity resonator apparatus
US2617071A (en) Ultrahigh-frequency electron discharge tube apparatus
US3852638A (en) Dither tuned microwave tube
US3020500A (en) Coaxial cavity tracking means and method
US2542908A (en) Mechanical tuner for cavity resonators
US3226662A (en) Mechanical frequency control in a klystron tube comprising a directly attached rectangular cavity resonator
US2559506A (en) Magnetron
US3167968A (en) Tuning mechanism
JPS6026443Y2 (ja) 周波数アジル型同軸マグネトロン
US2750565A (en) Altimeter modulators
US3942066A (en) Velocity modulation tube including a high resonance-frequency floating prebuncher having a q-value lower than a low resonance-frequency input cavity
US3227917A (en) Cavity resonator with flexible means forming both hermetic seal and pivot point