CN1147909C - Plate-type magnetron - Google Patents
Plate-type magnetronInfo
- Publication number
- CN1147909C CN1147909C CNB981052681A CN98105268A CN1147909C CN 1147909 C CN1147909 C CN 1147909C CN B981052681 A CNB981052681 A CN B981052681A CN 98105268 A CN98105268 A CN 98105268A CN 1147909 C CN1147909 C CN 1147909C
- Authority
- CN
- China
- Prior art keywords
- magnet
- yoke
- pair
- plate
- pole element
- 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 - Fee Related
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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
- H01J23/02—Electrodes; Magnetic control means; Screens
- H01J23/10—Magnet systems for directing or deflecting the discharge along a desired path, e.g. a spiral path
-
- 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
- H01J23/02—Electrodes; Magnetic control means; Screens
- H01J23/04—Cathodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
- H01J25/50—Magnetrons, i.e. tubes with a magnet system producing an H-field crossing the E-field
- H01J25/60—Magnetrons, i.e. tubes with a magnet system producing an H-field crossing the E-field with an electron space having a shape that prevents any electron from moving completely around the cathode or guide electrode; Linear magnetrons
Landscapes
- Microwave Tubes (AREA)
Abstract
A plate-type magnetron has a cathode for emitting electrons and a anode having vanes arranged at regular intervals thereon, forming an interaction space. Provided on both sides of the interaction space are a pair of pole pieces which are formed of bellows, and hence flexible in their length, and an adjustable magnetic portion. A yoke (15) is provided, which is used to alter the distance between the magnets, so that the frequency of the microwaves can be changed. In addition, a terminal hat to change the voltage thereon to change the output power of the microwave.
Description
The present invention relates to be applied to the plate-type magnetron of thermatron such as microwave oven etc., particularly, relate to the multifunctional flat type magnetron that the microwave with expectation power and frequency is provided effectively.
Magnetron is a cross(ed) field device, wherein produces the magnetic field and the electric field of quadrature in the interacting space of electron tube, and two kinds of types of oscillation are arranged, be i.e. A-type vibration and the vibration of B-type.
A-type vibration only depends on magnetic field intensity, and the Periodic Rotating motion of the electronics that is caused by magnetic field produces.Because be different from B-type oscillation mode (back will be described), cavity resonator etc. are very little to the influence of the wavelength of A type oscillation mode, and the wavelength of A type oscillation mode is only represented by the magnetic field decision and by following relation:
λ＝α/H
Here λ is an oscillation wavelength, and H is a magnetic field intensity, and α is 2 π mc/e.Herein, m is an electron mass, and e is an electron charge, so constant α is 10,650 in theory, but rule of thumb, its numerical value is from 10,000 to 13,000.
In this A type vibration, two kinds of electron orbits are arranged, a kind of energy that from alternating electric field, obtains, another kind gives the alternating electric field energy, therefore removes electronics in a kind of track in the past.
Below with reference to Fig. 1, vibration is described to the B-type.
Fig. 1 is the schematic diagram that traditional column type magnetron is constructed.As shown in the figure, a cylindrical anode 22 has one group of blade 22 that radially stretches to its center, has formed cavity resonator.One negative electrode 23 has formed the interacting space between negative electrode 23 and the blade 22 thus on the axis of this cylindrical anode.
Top and bottom at anode 21 are pole element 24, closely are connected respectively on the magnet 26 with yoke 25.Between anode 21 and yoke 25 for being used to discharge the radiation dish 27 of the heat that anode dissipation produces.When electronics of being launched by negative electrode 23 and being quickened by anode voltage and anode collision, this anode dissipation will increase.
Pair of electrodes (end cap) 30 intersects with magnetic direction or becomes a right angle, surrounds described interacting space.One negative voltage is applied on these end caps 30, so that electronics is limited in the interacting space.
In this set, the space in the anode 21 is evacuated.Along with the magnetic field in the interacting space that is produced by magnet 26 forms, when utilizing a power input part to divide 28 a high voltage is added on negative electrode 23 and the blade 22, electronics is just launched directive blade 22 from negative electrode 23.
Electrons emitted under the action of a magnetic field that produces by magnet 26 along the spiral or the track directive blade 22 that circles round.The result is that these electronics are released energy in cavity resonator, produce high-frequency electric field, and export as microwave by a microwave output 29.
As the electron source of magnetron, thermionic cathode is widely used now.Thermionic cathode is a kind of negative electrode that electron source is provided by thermionic emission.The mechanism of thermionic emission is that material is heated to 1500～2000 ° of K, makes the free electron of conduction region obtain to be equal to, or greater than the energy of material work function, launches thereby cross barrier at the material surface electronics.Thermionic cathode is made by simple metal or metal oxide etc., but at present, mainly uses a kind of by mixing barium (Ba) compound (5BaO2Al
2O
3CaO etc.) and tungsten (W) powder and press to burn thermal sintering type that this mixture obtains and a kind ofly inject the injection type that porous W forms by Ba compound with the melting attitude.Above-mentioned two types have high electron emission density, and have send the few advantage of gas when vacuumizing, and since the influence of the barium aluminium that uses when it is exposed in the air, can restore.
The electron source of another kind of form is a cold cathode, and cold cathode is a kind of negative electrode of the emitting electrons based on field emission rather than thermionic emission.The field emission is a kind of method of emitting electrons, and wherein, a high electric field is applied to also close material surface to reduce its surperficial potential barrier, utilizes the emission by tunnel effect electronics with this.This negative electrode is different from thermionic cathode, is called cold cathode owing to not heating.I-E characteristic can be approximate by the Fowler-Nodeheim formula.Figure 2 shows that the profile of cold cathode structure.Be formed with cutting-edge structure by metal or as the transmitter portion 90 that semiconductors such as Si constitute, producing a high-voltage gradient around it, and cover by metal film, this metal film and and transmitter portion between SiO
2The dielectric film 80 of film forms door 70.Therefore when a high voltage is applied on the door 70, a highfield produces on the tip of reflector, causes the electronics emission.Cold cathode is compared the advantage that has with thermionic cathode lower and provide electric current to obtain high current density with a kind of array format than thermionic cathode for working temperature.
At present the popular pattern that is applied to the magnetron in high-frequency heating apparatus such as the hot microwave oven is a column type.But also some magnetron adopts plate.Fig. 3 and Fig. 4 represent to have utilized the profile and the perspective view of the plate-type magnetron of cold cathode respectively.
Planar anode 41 shown in Figure 3 has the base part 51 that a plurality of blades 42 and that vertically are located on the negative electrode 43 constitute cavity resonator.Here, substrate 51 and negative electrode 43 equipotentials, but the part of its representative is different with negative electrode 43, and be not used in the electronics emission.Negative electrode 43 is placed in the lower left quarter of anode 41.Space between anode 41 and substrate 51-blade 42 forms an interacting space.One is used for being connected on the both sides of anode 41 at the pole element of interacting space formation uniform magnetic field the magnet of yoke.This yoke has the radiation dish that is used to discharge the heat that produces owing to anode dissipation.
In this structure, vacuum is pumped in the space in the anode 41.Along with magnetic field the forming in the interacting space that produces by magnet 46, be applied between door 60 and the substrate 51-blade 42 and between anode 41 and the substrate 51-blade 42 time when coming from voltage that power input part divides, as shown in Figure 2, electronics is launched to blade 42 from negative electrode 43.
So electrons emitted under the influence in the magnetic field that comes from magnet 46 to advance along the track dextrad of interacting space in Fig. 2 of circling round to mode similar in the column type magnetron, these electronics release energy to cavity resonator in advancing, produce high-frequency electric field, and export as microwave by a microwave output 49.
Use at magnetron under the situation of anode segment, may cause various mode of operations according to the quantity of section.The pattern that mainly is used in the vibration of B-type is called π-pattern, and the phase difference between the wherein adjacent resonance is the π radian, and the interaction between them is the strongest.
Yet, in the vibration of magnetron, if having another and this π-pattern to have the pattern of similar frequencies, will take place so by condition of work small saltus step triggered from the moding of this π-pattern to another kind of pattern.The result is that frequency of oscillation and power output sharply change.Therefore, must be positioned as close to, the resonance frequency of each pattern is scatter as much as possible by making humorous control device.
In traditional magnetron, the anode segment that replaces is crossed an electric conductor that forms equalizer ring with blade pass and is connected, so that a kind of pattern and another kind of pattern are separated.Because the voltage oscillation that this equalizer ring forces anode segment alternately to have a same-phase may be restricted to oscillation mode π-pattern and 0-pattern (in the 0-pattern, all anode segments and blade in-phase oscillation).
In this method, traditional microwave oven is configured and makes the application of the fixed magnetic field that produced by the magnet that is connected to yoke in the interacting space, can produce one and have the fixed frequency and the fixing microwave of power output.Correspondingly, power output that is obtained and frequency can not change according to its purposes.
Because magnetron has very useful characteristic, promptly very high frequency of oscillation, high power and low cost, except that microwave oven, magnetron is applied to the multiple technologies field.Correspondingly, how to realize that a multi-functional magnetron has become a major issue, described magnetron can be applied in the wide field as communication, radar, electronic installation etc.
Therefore, the objective of the invention is to address the above problem and provide a plate-type magnetron, this magnetron to serve many purposes and can produce microwave effectively with expectation power and frequency.
For achieving the above object, the following structure of the present invention.
According to a first aspect of the invention, a plate-type magnetron comprises:
One is used for the negative electrode of emitting electrons;
One has one group of anode of spaced blade according to certain rules on it;
One magnetic part, the interacting space that is used between negative electrode and anode produces uniform magnetic field; And
The electrode of a pair of relative arrangement, vertical with described uniform magnetic field, be in the both sides of interacting space, it is characterized in that described magnetic part can be adjusted the magnetic field intensity that produces to change in the interacting space.
Second aspect of the present invention is that this has the plate-type magnetron of above-mentioned first feature, and wherein said magnetic part comprises: a pair of pole element of placing of facing on the both sides, interacting space; And pair of magnet, this magnet is connected on the pole element and closely leans against on the yoke to form magnetic coupling, and wherein said magnet can move.
The 3rd aspect of the present invention is to have the plate-type magnetron of above-mentioned first feature, and wherein magnetic part comprises: a pair of pole element that is placed in face-to-face on the both sides, interacting space; And a pair ofly be connected on the pole element and closely contact to form magnetic-coupled magnet with yoke, the length of described pole element can change.
The 4th aspect of the present invention is to have above-mentioned first feature at plate-type magnetron, and wherein magnetic part comprises: a pair of pole element of settling face-to-face on the both sides of interacting space; And a pair of be connected on the pole element and near yoke to form magnetic-coupled pair of magnet, the length of described yoke can change.
According to a fifth aspect of the present invention, a plate-type magnetron comprises:
One negative electrode is used for emitting electrons;
One anode has one group of blade of settling at interval according to certain rules on it;
One magnetic part produces uniform magnetic field in the interacting space between negative electrode and anode; And
The magnetic pole of a pair of face-to-face arrangement, vertical with uniform magnetic field, be in the both sides of interacting space, it is characterized in that a positive voltage or negative voltage can selectively be applied on the described electrode.
In said method, power output can change with the change of electrode potential, and frequency can change with the distance between magnet.In addition, when a positive voltage is applied on the described electrode, can from the interacting space, remove the electronics of interference oscillatory.
Fig. 1 is the structural representation of traditional round column type magnetron;
Fig. 2 is the profile of traditional cold cathode structure;
Fig. 3 is the profile of classic flat-plate type magnetron;
Fig. 4 is the perspective view of classic flat-plate type magnetron; And
Fig. 5 is the profile according to plate-type magnetron of the present invention.
Below with reference to accompanying drawings embodiments of the invention are described.
Fig. 5 is the profile according to plate-type magnetron of the present invention.As shown in Figure 5, this plate-type magnetron comprises anode 11, blade 12, and negative electrode 13, pole element 14, yoke 15, magnet 16 and end cap 20 are formed.
One interacting space 18 that has been clipped in mutually vertical anode of placing 11 and the space definition between the negative electrode 13.18 horizontal direction both sides are pair of electrodes or aspectant end cap 20 in the interacting space, and positive voltage and negative voltage are applied on this electrode.A pair of being used for is oppositely arranged in the outside of end cap 20 at the field pole spare 14 that the interacting space generation requires.Pair of magnet 16 is located at pole element 14 outsides.Magnet 16 has a yoke 15, and yoke 15 contacts with anode 11.The contributive element in magnetic field to formation in interacting space 16 is mutual magnetic-coupled magnet 16, pole element 14 and yoke 15, and these elements are made the as a whole magnetic part that is called as.
Here, magnet 16 is ferrite-type, and is fixed on the sidewall of housing.Because yoke 15 also results from the radiant panel of anode loss heat as release, so it is the galvanized iron material.
In this plate-type magnetron, the air gap (gas length of magnetic part) that influences the magnetic part of the magnetic field intensity in the interacting space 18 can make it by the form that pole element 14 and yoke 15 is designed to bellows to change, so that the gas length in the magnetic part can change on the length of 20mm.Magnet 16 also moves with the variation of distance.
Anode 11 is that the building method that utilizes Japanese patent application to put down the plate-type magnetron of announcing in 8 No. 315742 is produced.
Next, will the operation principle of this plate-type magnetron be described.
At first, the bellows part by operation pole element 14 and yoke 15 is set as desired value with the gas length in the magnetic part, to form the magnetic field of expectation in the interacting space.During with the mode making alive similar to the traditional magnetron described in Fig. 3, electronics emits from negative electrode 13 and is advancing in interacting space 18 along the track that circles round under the influence in described magnetic field.The result is that these electronics release energy in cavity resonator, produce high-frequency electric field.So obtained to have with magnet between the relevant frequency of the regulated quantity of distance or pole element 14 and yoke 15 and the microwave of power output.
In being shown in the mean pole type magnetron of Fig. 5, a positive voltage or negative voltage can selectively be applied on the end cap 20, and magnet 16 can move, so yoke length and pole element length can change the microwave that has desired output power and frequency to provide.In other words, say that this plate-type magnetron is constructed such that the electronics of interference oscillatory is removed from the interacting space by the positive voltage that applies on end cap 20, and this voltage variableization is with the control power output.
Magnet 16 can move, and the pole element 14 of corrugated tube shape and yoke 15 can adjust to change pole element length and yoke length, and the gas length of magnetic part has been changed thus, thereby has controlled frequency.
For example, when anode voltage is arranged on 100 volts, anode-substrate distance is set at 0.5mm, magnetic field intensity is set at 1,360 Gauss (distance is set to 30mm between magnet), and end cap voltage is set at-10 volts, emission current just is 2.1 amperes, and the vibration power output is 160W (2.5GHZ).
When magnetic field intensity changed to 1,090 Gauss, microwave frequency was 3.1 to 3.5GHz, and the power output of vibration is 3 to 7W.Correspondingly, when the voltage of handle+10V was applied on the end cap 20, microwave frequency was 3.1 to 5.1GHz, and the power output of vibration is 10 to 20 watts, was approximately 3 times of the former power output.
As mentioned above, according to first to the 4th feature of the present invention,, therefore just can change frequency of oscillation by changing magnetic field intensity because magnetic part can be configured to change the magnetic field intensity that produces in the interacting space.Specifically, adjustment magnet, pole element length and yoke length change the magnetic field intensity corresponding to the gas length in the magnetic part, thereby have changed frequency.
According to the 5th feature,, when on these electrodes, having applied positive voltage, just can from the interacting space, remove the electronics of interference oscillatory because the electrode that can apply positive voltage or negative voltage is provided.
Though described the embodiment that has used a cold cathode, also can use thermionic cathode.
Claims (5)
1. plate-type magnetron comprises:
One negative electrode is used for emitting electrons;
One anode has one group of blade that is provided with according to certain rules on it;
One magnetic part, the interacting space that is used between described negative electrode and anode produces uniform magnetic field; And
The electrode of a pair of face-to-face arrangement, vertical with described uniform magnetic field, be in the both sides of interacting space,
Wherein, described magnetic part is adjustable, to change the magnetic field intensity that produces in the interacting space.
2. plate-type magnetron according to claim 1, wherein, described magnetic part comprises: a yoke, a pair of pole element of placing face-to-face on the both sides, interacting space; And pair of magnet, each magnet all is connected on the pole element, and near described yoke to form magnetic coupling, wherein said magnet can move.
3. plate-type magnetron according to claim 1, wherein, described magnetic part comprises: a yoke, a pair of pole element of placing face-to-face on the both sides, interacting space; And pair of magnet, each magnet all is connected on the pole element, and near described yoke forming magnetic coupling, and the variable-length of described pole element.
4. plate-type magnetron according to claim 1, wherein, described magnetic part comprises: a yoke, a pair of pole element of placing face-to-face on the both sides, interacting space; And pair of magnet, each magnet all is connected on the pole element, and near yoke forming magnetic coupling, and the variable-length of described yoke.
5. plate-type magnetron according to claim 1, wherein, a positive voltage or negative voltage can selectively be applied on the described electrode.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP04653297A JP3333421B2 (en) | 1997-02-28 | 1997-02-28 | Flat magnetron |
| JP46532/97 | 1997-02-28 | ||
| JP46532/1997 | 1997-02-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1192036A CN1192036A (en) | 1998-09-02 |
| CN1147909C true CN1147909C (en) | 2004-04-28 |
Family
ID=12749909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB981052681A Expired - Fee Related CN1147909C (en) | 1997-02-28 | 1998-02-20 | Plate-type magnetron |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0862198B1 (en) |
| JP (1) | JP3333421B2 (en) |
| KR (1) | KR100291396B1 (en) |
| CN (1) | CN1147909C (en) |
| DE (1) | DE69805238T2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010009047A (en) * | 1999-07-07 | 2001-02-05 | 김현순 | A Method of incredsing microwave electro-megnetic field intensity in the microwave chamber for dielectric heating |
| KR100721218B1 (en) * | 2000-06-07 | 2007-05-22 | 대우전자부품(주) | Separater for Deflection Yoke |
| KR20040050264A (en) * | 2002-12-10 | 2004-06-16 | 삼성전자주식회사 | Magnetron, Microwave oven, and High frequency heating apparatus |
| GB0416519D0 (en) * | 2004-07-23 | 2004-08-25 | Stenzel Security Ltd | Electronic apparatus |
| JP2013069602A (en) | 2011-09-26 | 2013-04-18 | Tokyo Electron Ltd | Microwave processor and workpiece processing method |
| CN103151230B (en) * | 2012-12-11 | 2015-05-13 | 中国人民解放军国防科学技术大学 | Long-pulse high conversion efficiency negative pole used for magnetron |
| CN108807116B (en) * | 2018-06-05 | 2021-02-02 | 电子科技大学 | Flattened magnetron for microwave oven adopting asymmetric magnetic circuit |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2496500A (en) * | 1945-07-18 | 1950-02-07 | Raytheon Mfg Co | Electron discharge device |
| BE625855A (en) * | 1962-03-15 | |||
| GB1449470A (en) * | 1973-07-06 | 1976-09-15 | Secr Defence | Crossed field amplifiers |
| FR2401509A1 (en) * | 1977-07-01 | 1979-03-23 | Cgr Mev | Variable output power magnetron parameter control - has relay controlled motor driven piston within one cavity and potentiometer controls electro magnet current |
| JP2699252B2 (en) * | 1993-04-14 | 1998-01-19 | 信越化学工業株式会社 | Permanent magnet variable magnetic field generator |
| JP3390562B2 (en) * | 1994-06-28 | 2003-03-24 | シャープ株式会社 | Magnetron and microwave oven |
| JP3165342B2 (en) * | 1994-12-05 | 2001-05-14 | シャープ株式会社 | Magnetron |
| JP3165343B2 (en) * | 1994-12-07 | 2001-05-14 | シャープ株式会社 | Anode for flat plate magnetron and method of manufacturing the same |
| JP3400233B2 (en) * | 1996-03-19 | 2003-04-28 | シャープ株式会社 | Magnetron and driving method thereof |
-
1997
- 1997-02-28 JP JP04653297A patent/JP3333421B2/en not_active Expired - Fee Related
-
1998
- 1998-02-16 EP EP98301106A patent/EP0862198B1/en not_active Expired - Lifetime
- 1998-02-16 DE DE69805238T patent/DE69805238T2/en not_active Expired - Fee Related
- 1998-02-20 CN CNB981052681A patent/CN1147909C/en not_active Expired - Fee Related
- 1998-02-26 KR KR1019980006067A patent/KR100291396B1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10241585A (en) | 1998-09-11 |
| KR100291396B1 (en) | 2001-07-12 |
| EP0862198A2 (en) | 1998-09-02 |
| JP3333421B2 (en) | 2002-10-15 |
| DE69805238D1 (en) | 2002-06-13 |
| KR19980071724A (en) | 1998-10-26 |
| EP0862198A3 (en) | 1998-11-11 |
| EP0862198B1 (en) | 2002-05-08 |
| CN1192036A (en) | 1998-09-02 |
| DE69805238T2 (en) | 2002-11-07 |
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