US3227976A - Damping means for shafts - Google Patents
Damping means for shafts Download PDFInfo
- Publication number
- US3227976A US3227976A US127934A US12793461A US3227976A US 3227976 A US3227976 A US 3227976A US 127934 A US127934 A US 127934A US 12793461 A US12793461 A US 12793461A US 3227976 A US3227976 A US 3227976A
- Authority
- US
- United States
- Prior art keywords
- shaft
- tuner
- support shell
- tuning
- shell
- 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
- 238000013016 damping Methods 0.000 title description 5
- 230000007246 mechanism Effects 0.000 claims description 27
- 230000001050 lubricating effect Effects 0.000 claims description 14
- 230000033001 locomotion Effects 0.000 claims description 11
- 230000011514 reflex Effects 0.000 description 6
- 230000002093 peripheral effect Effects 0.000 description 4
- WAKHLWOJMHVUJC-FYWRMAATSA-N (2e)-2-hydroxyimino-1,2-diphenylethanol Chemical compound C=1C=CC=CC=1C(=N/O)\C(O)C1=CC=CC=C1 WAKHLWOJMHVUJC-FYWRMAATSA-N 0.000 description 3
- 230000003993 interaction Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910000861 Mg alloy Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910000676 Si alloy Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000012260 resinous material Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/10—Suppression of vibrations in rotating systems by making use of members moving with the system
- F16F15/12—Suppression of vibrations in rotating systems by making use of members moving with the system using elastic members or friction-damping members, e.g. between a rotating shaft and a gyratory mass mounted thereon
- F16F15/129—Suppression of vibrations in rotating systems by making use of members moving with the system using elastic members or friction-damping members, e.g. between a rotating shaft and a gyratory mass mounted thereon characterised by friction-damping means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
-
- 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
-
- 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
- H01J23/36—Coupling devices having distributed capacitance and inductance, structurally associated with the tube, for introducing or removing wave energy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
- H01J25/02—Tubes with electron stream modulated in velocity or density in a modulator zone and thereafter giving up energy in an inducing zone, the zones being associated with one or more resonators
- H01J25/22—Reflex klystrons, i.e. tubes having one or more resonators, with a single reflection of the electron stream, and in which the stream is modulated mainly by velocity in the modulator zone
- H01J25/24—Reflex klystrons, i.e. tubes having one or more resonators, with a single reflection of the electron stream, and in which the stream is modulated mainly by velocity in the modulator zone in which the electron stream is in the axis of the resonator or resonators and is pencil-like before reflection
-
- 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
- Y10T74/20—Control lever and linkage systems
- Y10T74/20576—Elements
- Y10T74/20636—Detents
- Y10T74/2066—Friction
Definitions
- the invention is disclosed as applied to an electron tube tuner mechanism.
- Reflex klystrons for instance, because of their small size and light weight, are often used in applications that require a maximum amount of reliability.
- These tubes also incorporate tuner mechanisms utilizing a rotary screw shaft for advancing and retracting a tuning member into a resonant cavity, and specific limitations are placed on the range of torque required to rotate the shaft. It will readily be understood that in a tuner mechanism which is designed to be cycled approximately 2,500 times, and heat cycled through temperatures ranging between 45 C. to 125 C., it is extremely difiicult to eliminate vibration and control the range of applied torque by which the tuner mechanism is operated.
- a tuner mechanism employing a rotary shaft in which the torque required to turn the shaft is maintained within the range of to 40 inch ounces over 2,500 cycles of operation through variations in temperature ranging between 45 C. to 125 C.
- AM and FM noise may arise from the distortion of electrical and magnetic fields within the resonant cavity, and from impedance changes along the threaded portion of the tuner shaft in tubes using screw shaft tuning mechanisms. It has been found that when vibration causes minute move ments of the tuner shaft relative to its supporting shell and the cavity, both the electrical and magnetic fields within the cavity are distorted and the impedance along the threaded portion of the tuning shaft varies, thus giving rise to such noise. It is therefore another important object of the. invention to provide a screw shaft tuner mechanism for an electron tube in which tuner generated noise is minimized.
- the invention as embodied in an electron tube of the 2-cavity reflex klystron type comprises a generally cylindrical electron tube body portion having therewithin a cathode-heater assembly operatively aligned with a plurality of grids defining an interaction gap within the klystron for interaction with an electron beam projected from the cathode to the repeller.
- the gap defined by the grids forms a part of a primary resonant cavity, and the cavity is connected by a radio frequency window with an auxiliary or tuning cavity adapted to be interposed between the tube body and a wave guide.
- a flange on the auxiliary cavity provides means for securing the tube structure to the waveguide.
- a rotatable screw shaft mechanism and tuning member are provided to adjust the operating frequency of the resonant cavity.
- the tuning mechanism incorporates means for minimizing mechanical vibration and eliminating jitter, and for maintaining within predetermined limits the torque required to rotate the screw shaft.
- FIGURE 1 is a plan view partly in section illustrating the relationship between the tuner mechanism and the tube.
- FIGURE 2 is a sectional view taken in the plane indicated by the line 22 of FIGURE 1.
- the reflex klystron and tuner mechanism embodying the invention comprises a hollow metallic cylindrical tube body 2 symmetrical about a longitudinally extending axis, and having a pair of transversely extending apertured plates 3 and 4 therewithin and axially spaced apart to define a cathode chamber 6, a primary resonant cavity 7 and a repeller chamber 8.
- a cathode 9 appropriately heated by means of a heater coil 12, to generate a beam of electrons which is appropriately focused by focus electrode 13.
- the electrons of the beam are accelerated by an anode accelerating grid 14 supported on plate 3, and are permitted to drift through a drift tube 16, from which they pass through gap entrance grid 17, interaction gap 18, and exit grid 19.
- Cavity 22 comprises a primary resonant cavity in the tube, and is coupled to a secondary cavity 23 having one wall 24 thereof forming a part of the tube body and having an aperture 26 therein hermetically closed by radio frequency window 27.
- the secondary or auxiliary cavity 23 is provided with side wall members 28 integrally and hermetically united to end wall 24 and defining the configuration of cavity 23.
- the side walls 2% are closed on the ends thereof remote from wall 24 by wall 29 having aperture 31 therein for coupling electromagnetic energy into an adjoining or associated waveguide (not shown) adapted to be attached to the mounting flange 32.
- the auxiliary cavity 23 extends perpendicularly to the longitudinal axis of the tube, and is provided with adjustable plug 33 to optimize the coupling between the primary and auxiliary cavities.
- a tuner mechanism is provided adjustably mounted on the auxiliary cavity 23.
- the tuner mechanism is preferably of the screw type having a longitudinal axis parallel to the axis of the tube, and incorporates a tuning shaft 34 having threads 3% intermediate its ends adapted to work in threads 37 formed on the inside periphery 38 of a hollow tuner support shell or housing 3.
- the outer end of the tuner shaft is provided with a screw driver slot 41 to facilitate adjustment.
- the tuner support shell 39 is provided with a cylindrical bore and is detachably connected at one end 42 to the auxiliary cavity wall 253. This connection is effectively made by means of threads 43 internally formed in the support shell 39 and adapted to engage threads 44 formed on integral cavity extension 46.
- the end of the tuner support shell adjacent the auxiliary cavity is enlarged in internal diameter over the diameter of the shell where threads 37 occur.
- This increase in diameter of the shell adjacent the auxiliary cavity wall provides an annular space between the inner end of tuner shaft 34 and the end of the shell.
- Centrally mounted within this space, to provide an annular space 47 immediately surrounding the tuner shaft and a second concentric annular space 48 immediately adjacent the tuner support shell is a cylindrical metallic sleeve 49 having one end 51 thereof integrally united, within aperture 52, to wall 28 of the auxiliary cavity.
- the cylindrical sleeve 49 extends away from wall 28 and terminates in a free end 53 axially spaced from the smaller diameter internally threaded portion of the tuner support shell.
- the outer free end of the tuner support shell is provided with a bore 54 closely encircling a portion of the outer cylindrical peripheral surface of the screw shaft but radially spaced therefrom a small amount.
- Formed in the upper portion 56 of the tuner support shell are a plurality of radially extending circumferentially equally spaced bores 57, preferably six in number spaced 60 apart.
- Movably supported in alternate bores 57 are a plurality of metallic friction members or plugs 58 having their inner ends 59 frictionally engaging the smooth outer peripheral surface of the adjacent tuner shaft.
- the friction members are retained in their respective bores by a split spring ring 61 circumscribing the outer ends of the friction members and riding in groove 62 formed in the exterior surface of the shell portion 56.
- the split spring ring 61 exerts a continuous uniform pressure on the outer ends of the friction members or plugs and causes the plugs to impinge with uniform force and friction on the surface of the tuner shaft, thus maintaining the frictional resistance to movement of the shaft constant. It has been found that friction members formed from Cupron, an alloy of nickel, magnesium, silicon, iron and copper, and sold by the Wilbur B. Driver Company, perform satisfactorily in this environment.
- alternate bores 57 in the tuner support shell be provided with lubricating members or plugs 63.
- lubricating members or plugs 63 are conveniently formed from a non-metallic synthetic resinous material sold under the trade name Teflon.
- Teflon a non-metallic synthetic resinous material sold under the trade name Teflon.
- the lubricating plugs are movably int rposed between the outer peripheral surface of the tuner shaft and the inner peripheral surface of the split spring ring 61, and are therefore also resiliently urged inwardly against the shaft as are the friction members 58.
- the inner ends of the lubricating plugs ride on the surface of the tuner shaft, and with rotation of the shaft lubricate the surface of the screw shaft defined by the track of the friction members to control the frictional resistance between the friction members and the tuner shaft.
- the surface of the shaft is preferably plated with a metal which will provide a hard surface. Satisfactory results have been obtained with a hard nickel plate. Friction plugs and lubricating plugs thus have an effective chucking action on the shaft at a point axially spaced from the threaded portion of the shaft to maintain the shaft axially aligned within the shell.
- a tuning mechanism for tuning the cavity to a desired operating frequency and comprising a hollow support shell extending from said tube, a tuning shaft movably supported in the hollow support shell for movement upon application of a force thereto falling within a predetermined range, said shaft having a smooth surface portion within said shell, and means on said hollow support shell to damp vibration of said tuning shaft and maintain within said predetermined range the force required to move said shaft, said means comprising at least one friction member movably supported on said hollow support shell and impinging against said smooth portion of said shaft, and at least one lubricating member movably supported on said hollow support shell to lubricate the track of said friction member on the shaft upon relative movement therebetween.
- a tuning mechanism for tuning the cavity to a desired operating frequency comprising a hollow support shell mounted on the tube, a screw threaded shaft having its screw threads friction-ally engaging matching threads in the hollow support shell and adapted to be selectively advanced or retracted in relation to the shell upon application of torque to the shaft within a predetermined range, and means on said hollow support shell to damp vibration of said screw shaft and maintain within the limits of said predetermined range the torque required to rotate said shaft, said means comprising radially extending circumferentially spaced bores in said shell, friction plugs movably supported in said bores and frictionally impinging against said smooth portion of the shaft, and resilient means urging said plugs radially inwardly.
- each friction plug comprises a metallic body
- each lubricating member comprises a non-metallic body
- said means interconnecting said friction plugs and lubricating members comprises a split spring ring.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Aviation & Aerospace Engineering (AREA)
- Mechanical Engineering (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
- Microwave Tubes (AREA)
- Transmission Devices (AREA)
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL281287D NL281287A (de) | 1961-07-31 | ||
| US127934A US3227976A (en) | 1961-07-31 | 1961-07-31 | Damping means for shafts |
| GB26329/62A GB1011533A (en) | 1961-07-31 | 1962-07-09 | Improved damped control mechanism |
| CH900862A CH405511A (de) | 1961-07-31 | 1962-07-26 | In einer Elektronenröhre mit einem Resonanzhohlraum angeordneter Abstimmechanismus |
| DEE23279A DE1294566B (de) | 1961-07-31 | 1962-07-27 | Mechanisch abstimmbarer Hohlraumresonator fuer Laufzeitroehren |
| FR905667A FR1330074A (fr) | 1961-07-31 | 1962-07-31 | Perfectionnements aux systèmes d'amortissement pour arbres en rotation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US127934A US3227976A (en) | 1961-07-31 | 1961-07-31 | Damping means for shafts |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3227976A true US3227976A (en) | 1966-01-04 |
Family
ID=22432714
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US127934A Expired - Lifetime US3227976A (en) | 1961-07-31 | 1961-07-31 | Damping means for shafts |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US3227976A (de) |
| CH (1) | CH405511A (de) |
| DE (1) | DE1294566B (de) |
| GB (1) | GB1011533A (de) |
| NL (1) | NL281287A (de) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3528042A (en) * | 1967-09-22 | 1970-09-08 | Motorola Inc | Temperature compensated waveguide cavity |
| US4750596A (en) * | 1985-10-11 | 1988-06-14 | Valeo | Control mechanism for a coupling device such as a clutch, variable speed drive, brake or the like |
| US4890641A (en) * | 1988-12-06 | 1990-01-02 | Teledyne Inc., Teledyne Farris Eng. Div. | Frictional damper suitable for pressure relief valves |
| US20120205566A1 (en) * | 2011-02-10 | 2012-08-16 | Zama Japan Corporation | Throttle valve device |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB459782A (en) * | 1935-06-14 | 1937-01-14 | Anglo Iranian Oil Co Ltd | Improvements relating to couplings for conveying rotary motion |
| US2166739A (en) * | 1927-11-16 | 1939-07-18 | North American Rayon Corp | Manufacture of artificial silk |
| US2852719A (en) * | 1952-11-29 | 1958-09-16 | Litton Industries Inc | Tunable magnetron |
| US2884602A (en) * | 1955-09-02 | 1959-04-28 | Marconi Wireless Telegraph Co | Transmit-receive cells |
| US2945983A (en) * | 1959-05-05 | 1960-07-19 | Bomac Lab Inc | Electrode support for electron discharge devices |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2940002A (en) * | 1958-01-02 | 1960-06-07 | Varian Associates | Klystron amplifier |
-
0
- NL NL281287D patent/NL281287A/xx unknown
-
1961
- 1961-07-31 US US127934A patent/US3227976A/en not_active Expired - Lifetime
-
1962
- 1962-07-09 GB GB26329/62A patent/GB1011533A/en not_active Expired
- 1962-07-26 CH CH900862A patent/CH405511A/de unknown
- 1962-07-27 DE DEE23279A patent/DE1294566B/de active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2166739A (en) * | 1927-11-16 | 1939-07-18 | North American Rayon Corp | Manufacture of artificial silk |
| GB459782A (en) * | 1935-06-14 | 1937-01-14 | Anglo Iranian Oil Co Ltd | Improvements relating to couplings for conveying rotary motion |
| US2852719A (en) * | 1952-11-29 | 1958-09-16 | Litton Industries Inc | Tunable magnetron |
| US2884602A (en) * | 1955-09-02 | 1959-04-28 | Marconi Wireless Telegraph Co | Transmit-receive cells |
| US2945983A (en) * | 1959-05-05 | 1960-07-19 | Bomac Lab Inc | Electrode support for electron discharge devices |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3528042A (en) * | 1967-09-22 | 1970-09-08 | Motorola Inc | Temperature compensated waveguide cavity |
| US4750596A (en) * | 1985-10-11 | 1988-06-14 | Valeo | Control mechanism for a coupling device such as a clutch, variable speed drive, brake or the like |
| US4890641A (en) * | 1988-12-06 | 1990-01-02 | Teledyne Inc., Teledyne Farris Eng. Div. | Frictional damper suitable for pressure relief valves |
| US20120205566A1 (en) * | 2011-02-10 | 2012-08-16 | Zama Japan Corporation | Throttle valve device |
| US8733730B2 (en) * | 2011-02-10 | 2014-05-27 | Zama Japan Kabushiki Kaisha | Throttle valve device |
| US9422891B2 (en) | 2011-02-10 | 2016-08-23 | Zama Japan Kabushiki Kaisha | Throttle valve device |
Also Published As
| Publication number | Publication date |
|---|---|
| CH405511A (de) | 1966-01-15 |
| NL281287A (de) | |
| DE1294566B (de) | 1969-05-08 |
| GB1011533A (en) | 1965-12-01 |
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