JPH01309234A - Magnetron - Google Patents
MagnetronInfo
- Publication number
- JPH01309234A JPH01309234A JP13997488A JP13997488A JPH01309234A JP H01309234 A JPH01309234 A JP H01309234A JP 13997488 A JP13997488 A JP 13997488A JP 13997488 A JP13997488 A JP 13997488A JP H01309234 A JPH01309234 A JP H01309234A
- Authority
- JP
- Japan
- Prior art keywords
- filament
- cathode
- tungsten
- lanthan
- magnetron
- 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.)
- Pending
Links
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims abstract description 15
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000000843 powder Substances 0.000 claims abstract description 8
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 7
- 239000010937 tungsten Substances 0.000 claims abstract description 7
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 4
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 3
- 239000011733 molybdenum Substances 0.000 claims abstract description 3
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 3
- 229910052746 lanthanum Inorganic materials 0.000 claims description 12
- 239000003870 refractory metal Substances 0.000 claims 1
- WLTSUBTXQJEURO-UHFFFAOYSA-N thorium tungsten Chemical compound [W].[Th] WLTSUBTXQJEURO-UHFFFAOYSA-N 0.000 abstract description 7
- 238000001994 activation Methods 0.000 abstract description 5
- 238000002844 melting Methods 0.000 abstract description 2
- 230000008018 melting Effects 0.000 abstract description 2
- 229910052751 metal Inorganic materials 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- NEIHULKJZQTQKJ-UHFFFAOYSA-N [Cu].[Ag] Chemical compound [Cu].[Ag] NEIHULKJZQTQKJ-UHFFFAOYSA-N 0.000 description 2
- 230000004913 activation Effects 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000000020 Nitrocellulose Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000002659 electrodeposit Substances 0.000 description 1
- 238000001962 electrophoresis Methods 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229920001220 nitrocellulos Polymers 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 210000003462 vein Anatomy 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Microwave Tubes (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は電子レンジ等に使用されるマグネトロンに関す
るものであり、さらに詳細に言えば改良された陰極構体
を有するマグネトロンに関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetron used in a microwave oven or the like, and more particularly to a magnetron having an improved cathode structure.
従来の技術
従来の電子レンジ等に使用されるマグネトロンの構造を
第５図に示す。同図において、１は陽極円筒、２は陽極
円筒内に配設された複数のベイン、３はベインの陽極円
筒管軸方向の両端側に配設され複数のベインとそれぞれ
交互に１つお巻に接続された２対のリングからなるスト
ランプリング、４はアンテナリードであり一端が複数の
ベインの任意の１つに所望の位置で接続されており陽極
円筒端に設けられたポールピース５の結合孔６を貫通し
て他端が陽極円筒管軸方向に配された出力アンテナ部７
まで延在する。このアンテナリード４は、陽極円筒内を
真空排気する時の排気路となる排気パイプ８と同時に切
断され図に示す如く排気パイプの切断部で排気パイプと
一体的に接続固定されている。2. Description of the Related Art FIG. 5 shows the structure of a magnetron used in a conventional microwave oven. In the same figure, 1 is an anode cylinder, 2 is a plurality of vanes arranged inside the anode cylinder, and 3 is arranged on both ends of the vane in the axial direction of the anode cylinder tube, and one coil is wound alternately with the plurality of vanes. 4 is an antenna lead, one end of which is connected to any one of the plurality of vanes at a desired position, and a pole piece 5 provided at the end of the anode cylinder. An output antenna part 7 passes through the coupling hole 6 and has the other end arranged in the axial direction of the anode cylindrical tube.
extends up to The antenna lead 4 is cut at the same time as the exhaust pipe 8, which serves as an exhaust path when the anode cylinder is evacuated, and is integrally connected and fixed to the exhaust pipe at the cut portion of the exhaust pipe, as shown in the figure.
また、９は陰極部であり陽極円筒の中央部に陽極円筒と
同心状に配設されたらせん状のフィラメントより構成さ
れ、その両端にはエンドハント１０．１１を配する。各
エンドハツトは、陽極円筒管軸方向に配された支持リー
ド１２．１３とそれぞれ接続されている。各支持リード
は、出力アンテナ部と反対側の陽極円筒端面側に配され
たセラミック材からなるカソードステム１４に銀銅ろう
付され、このカソードステムは銀銅ろう付されたカソー
ド側管１５を介して陽極円筒端面に固定組立されている
。１６はカソードステム側のポールピース、１７．１８
はカソードステム側への不要輻射抑制用の誘電体部材お
よび金属管、１９゜２０は永久磁石、２１は陽極円筒管
に圧入組立されな放熱フィン、２２．２３は磁気回路を
形成する継鉄、２４はコア人チョークコイル、２５は貫
通コンデンサ、２６はフィルタボックスである。The cathode section 9 is composed of a spiral filament arranged concentrically with the anode cylinder at the center of the anode cylinder, and end hunts 10 and 11 are arranged at both ends of the helical filament. Each end hat is connected to a support lead 12, 13 arranged in the axial direction of the anode cylinder tube. Each support lead is silver-copper soldered to a cathode stem 14 made of a ceramic material disposed on the end face of the anode cylinder opposite to the output antenna part, and this cathode stem is connected via a silver-copper brazed cathode side tube 15. The anode is fixedly assembled on the end face of the anode cylinder. 16 is the pole piece on the cathode stem side, 17.18
19, 20 are permanent magnets, 21 are heat dissipation fins that are press-fitted into the anode cylindrical tube, 22 and 23 are yoke forming a magnetic circuit, 24 is a core choke coil, 25 is a feedthrough capacitor, and 26 is a filter box.
第６図はベイン２．陰極部９の中心線Ａ −Ａ’に沿っ
た断面の上面図であり、ｒ、ｒ はそれぞＣａ
れ陰極半径、陽極半径である。第７図は陰極線断面の拡
大図であり、トリウムタングステン２７とタングステン
カーバイド（Ｗ２Ｃ）２８の２層構造となっており全直
径は０．５〜０．６ ｒｎｍである。Figure 6 shows Vane 2. It is a top view of a cross section taken along the center line A-A' of the cathode part 9, where r and r are the cathode radius and the anode radius, respectively. FIG. 7 is an enlarged view of a cross section of the cathode ray, which has a two-layer structure of thorium tungsten 27 and tungsten carbide (W2C) 28, and has a total diameter of 0.5 to 0.6 nm.
このようなマグネトロンにおいて、ｒ、＝２ｒｎｒｎ、
ｒ ＝ ４．５ ｍｍ 、ベイン高さ１０ｍｍ、陰極
長さ１４．５ ｍｍとし、陰極−陽極間に４０ｏＯボル
トの半波整流電圧を印加し、電場と直交して１７５０ガ
ウスの磁場をかけると２４５０ＭＨｚのマイクロ波を発
振する。陰極は陽極と溶接後、内部を真空排気しながら
トリウムタングステンフィラメントに通電して２３５０
６にに温度を上げタングステンカーバイドを形成しく活
性化処理）、熱電子放射性を上げ１９００°にで使用す
る。In such a magnetron, r,=2rnrn,
When r = 4.5 mm, vane height 10 mm, and cathode length 14.5 mm, a half-wave rectified voltage of 40 oO volts is applied between the cathode and anode, and a magnetic field of 1750 Gauss is applied perpendicular to the electric field, the frequency is 2450 MHz. oscillates microwaves. After welding the cathode to the anode, the thorium tungsten filament is energized to 2350°C while the inside is evacuated.
The temperature is raised to 1900° to increase the temperature (activation treatment to form tungsten carbide) and thermionic emission.
発明が解決しようとする課題
しかしながら上記のような構成で図外の高圧トランス（
重ｆｆ１４ｋａ程度、電子レンジ重量の３６％を占める
）を省き２００ボルトで駆動させるためには３６枚以上
のベインを配設する必要がある。Problems to be Solved by the Invention However, with the above configuration, a high voltage transformer (not shown)
In order to drive the microwave oven at 200 volts while eliminating the weight (approximately 14 ka of weight, which accounts for 36% of the weight of the microwave oven), it is necessary to provide 36 or more vanes.
ところが従来のｒ、＋−では３６枚以上のペイＣＩ＆
ンを配設することは困難であり、ｒ、ｒ を犬Ｃａ
きくする必要がある。しかし従来のトリウムタングステ
ン線でｒｏを大きくすると２３５０°にで活性化処理す
ると熱変形が起るという課題を有していた。本発明はか
かる従来の課題を解決するもので、従来より寸法の大き
い熱電子放射体を有する陰極構体を配設した低電圧駆動
マグネトロンを提供することを目的とする
課題を解決するための手段
上記課題を解決するために本発明のマグネトロンは直径
０．３〜１ｍｍのタングステン、モリブデン、タンタル
の群から選んだ高融点金属線で外径６〜１５ｍｍ 、長
さ１５〜３０ｍｍのらせん状フィラメントを形成し、前
記フィラメント表面に６ホウ化ランタン粉末を被覆した
熱電子放射体を有する陰極構体を配設したものとした。However, with the conventional r, +-, it is difficult to arrange 36 or more pay CI&, and it is necessary to increase r, r. However, when using conventional thorium tungsten wires with a large ro, thermal deformation occurs when activated at 2350°. The present invention solves such conventional problems, and aims to provide a low-voltage driven magnetron equipped with a cathode structure having a thermionic emitter larger in size than the conventional one. In order to solve the problem, the magnetron of the present invention forms a helical filament with an outer diameter of 6 to 15 mm and a length of 15 to 30 mm using a high melting point metal wire selected from the group of tungsten, molybdenum, and tantalum with a diameter of 0.3 to 1 mm. A cathode structure having a thermionic emitter coated with lanthanum hexaboride powder was disposed on the surface of the filament.
作 用
上記構成によって熱電子放射温度は１９００°Ｋ（トリ
ウムタングステン）から１７５０°に（６ホウ化ランタ
ン）に低下するとともに、２３５０’ににおける活性化
処理が不要となるためフィラメントの大形化ができ低電
圧駆動マグネトロンができるようになる。Effect With the above configuration, the thermionic emission temperature is lowered from 1900°K (thorium tungsten) to 1750° (lanthanum hexaboride), and the activation process at 2350° is not required, so the filament can be made larger. A low voltage drive magnetron will be possible.
実施例
以下、本発明の実施例を添付図面にもとづいて説明する
。第１図において２９は直径０．５ ｍｍのタングステ
ン線を外径７ ｍｍ 、高さ２０ ｍｍ 、巻数１５に
加工したタングステンフィラメント表面に６ホウ化ラン
タン（ＬａＢ６）粉末を被覆した熱電子放射体を有する
陰極構体である。フィラメント寸法は第５図に示す従来
品の寸法（直径０．５ｒｎｍのトリウムタングステン線
を外径４ｍｍ、高さ１４．５ ｍｍ 、巻数１０に加工
）と対比することができる。もしこのような大形フィラ
メントをトリウムタングステンでつくり、放射電流密度
を増すために５Ｘ１０ ’パスカルの高真空中で通電
して２３５０’Ｋに加熱して活性化処理すると熱変形を
起し形状、寸法が変形し実用に供することができない。Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In Figure 1, 29 is a thermionic emitter whose surface is coated with lanthanum hexaboride (LaB6) powder, which is a tungsten filament made by processing a tungsten wire with a diameter of 0.5 mm into an outer diameter of 7 mm, a height of 20 mm, and a number of turns of 15. It is a cathode structure having The filament dimensions can be compared with those of the conventional product shown in FIG. 5 (a thorium tungsten wire with a diameter of 0.5 rnm is processed to have an outer diameter of 4 mm, a height of 14.5 mm, and a number of turns of 10). If such a large filament is made of thorium tungsten and activated by heating it to 2350'K while being energized in a high vacuum of 5 x 10' Pascals to increase the radiation current density, it will undergo thermal deformation and its shape and dimensions will change. is deformed and cannot be put to practical use.
本実施例の陰極構体は第２図に示すような電気泳動装置
によりタングステンフィラメント表面に６ホウ化ランタ
ン粉末を被覆する。同図において３１は電解槽、３２は
陰極、３３は直流電源である。電解槽３１には６ホウ化
ランタン粉末と有機結合材として微量のニトロセルロー
ズ、溶媒としてエチルアルコールからなる溶液を入れ、
Ｍ記溶液中にタングステンフィラメントを浸漬し、直流
電源３３によりフィラメントと陽極間に直流電圧を印加
し、正に帯電した６ホウ化ランタン粒子をフィラメント
上に電着する。第３図は陰極線断面の拡大図でありタン
グステン３４と６ホウ化ランタン粉末層３５との２層構
造となっている。In the cathode structure of this embodiment, the surface of a tungsten filament is coated with lanthanum hexaboride powder using an electrophoresis apparatus as shown in FIG. In the figure, 31 is an electrolytic cell, 32 is a cathode, and 33 is a DC power source. In the electrolytic cell 31, a solution consisting of lanthanum hexaboride powder, a trace amount of nitrocellulose as an organic binder, and ethyl alcohol as a solvent is placed.
A tungsten filament is immersed in the M solution, and a DC voltage is applied between the filament and the anode by a DC power supply 33 to electrodeposit positively charged lanthanum hexaboride particles onto the filament. FIG. 3 is an enlarged view of a cathode ray cross section, and has a two-layer structure of tungsten 34 and lanthanum hexaboride powder layer 35.
第４図は第１図におけるベイン３０と陰極部２９の中心
線Ａ −Ａ’に沿った断面の上面図であり、厚さ０．４
ｍｍ 、高さ１５ｍｍの銅製ベイン３６枚を放射状に
配設したものであり、ｒ ｃ ＝ ３．５ ｍｍ、１
Ｂ ＝ ７．０ ｍｒｎとし、陰極−陽極間に２００ボ
ルトの半波整流電圧を印加し、電場と直交して９０ガウ
スの磁場をかけると２４５０ＭＨｚ で発振した。こ
の時の陰極温度は１７５０°にであった。FIG. 4 is a top view of a cross section of the vane 30 and cathode section 29 taken along the center line A-A' in FIG.
mm, 36 copper vanes with a height of 15 mm are arranged radially, r c = 3.5 mm, 1
When B = 7.0 mrn, a half-wave rectified voltage of 200 volts was applied between the cathode and anode, and a magnetic field of 90 Gauss was applied perpendicular to the electric field, oscillation occurred at 2450 MHz. The cathode temperature at this time was 1750°.
タングステン線の代りにモリブデン線あるいはタンタル
線をフィラメント状に加工し、外周に６ホウ化ランタン
を被覆した陰極構体を有するマグネトロンでも同様の結
果が得られた。Similar results were obtained with a magnetron having a cathode structure in which a molybdenum wire or a tantalum wire was processed into a filament instead of a tungsten wire, and the outer periphery was coated with lanthanum hexaboride.
種々検討の結果陰極温度を１了５０°にとしたとき線径
０．３〜ｊｍｍで熱変形が少なく長期間マグネトロンに
使用し得るフィラメントの最大外径は１５ ｍｍ 、最
大長は３０ｍｍであった。As a result of various studies, when the cathode temperature was set to 50°, the maximum outer diameter of a filament with a wire diameter of 0.3 to 50 mm, which could be used for long periods of time in magnetrons with little thermal deformation, was 15 mm and maximum length was 30 mm. .
発明の効果
以上のように本発明のマグネトロンによれば次の効果が
得られる。Effects of the Invention As described above, the magnetron of the present invention provides the following effects.
（１）熱電子放射体として６ホウ化ランタンを使用する
ことにより活性化処理が不要となり外径、長さの大きい
フィラメントが使用できるという効果がある。(1) The use of lanthanum hexaboride as the thermionic emitter eliminates the need for activation treatment and has the advantage that filaments with large outer diameters and lengths can be used.
（２）大形フィラメントの使用により、低電圧駆動マグ
ネトロンの製造ができる。(2) The use of large filaments allows the manufacture of low-voltage driven magnetrons.
第１図は本発明の一実施例におけるマグネトロンの断面
図、第２図は同６ホウ化ランタンの被覆装置の断面図、
第３図は同陰極線の拡大断面図、第４図は同陰極−陽極
部の要部拡大断面図、第５図は従来例断面図、第６図は
同陰極−陽極部の要部拡大断面図、第７図は同陰極線の
拡大断面図である。
２９・・・・・・陰極構体、３０・・・・・・ベイン、
３５・・・・・・６ホウ化ランタン。
代理人の氏名 弁理士 中 尾 敏 男 ほか１名２９
−Ｆ！極獲体
３０−’ベイン
第１図
ｉＥ２ 図
第４図
羽
第５図
２３６図
第７図FIG. 1 is a sectional view of a magnetron according to an embodiment of the present invention, and FIG. 2 is a sectional view of a lanthanum hexaboride coating device.
Fig. 3 is an enlarged sectional view of the cathode ray, Fig. 4 is an enlarged sectional view of the main part of the cathode-anode part, Fig. 5 is a sectional view of the conventional example, and Fig. 6 is an enlarged sectional view of the main part of the cathode-anode part. FIG. 7 is an enlarged sectional view of the same cathode ray. 29... Cathode structure, 30... Vane,
35...6 lanthanum boride. Name of agent: Patent attorney Toshio Nakao and 1 other person29
-F! Polar catch 30-' Vein Figure 1 iE2 Figure 4 Wings Figure 5 236 Figure 7
Claims (1)
径０．３〜１ｍｍの高融点金属線で外径６〜１５ｍｍ）
長さ１５〜３０ｍｍのらせん状フィラメントを形成し、
前記フィラメント表面に６ホウ化ランタン粉末を被覆し
た熱電子放射体を有する陰極構体を配設したマグネトロ
ン。Refractory metal wire with a diameter of 0.3 to 1 mm selected from the group of tungsten, molybdenum, and tantalum (outer diameter 6 to 15 mm)
Forming a helical filament with a length of 15 to 30 mm,
A magnetron comprising a cathode structure having a thermionic emitter coated with lanthanum hexaboride powder on the surface of the filament.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13997488A JPH01309234A (en) | 1988-06-07 | 1988-06-07 | Magnetron |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13997488A JPH01309234A (en) | 1988-06-07 | 1988-06-07 | Magnetron |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01309234A true JPH01309234A (en) | 1989-12-13 |
Family
ID=15258002
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13997488A Pending JPH01309234A (en) | 1988-06-07 | 1988-06-07 | Magnetron |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01309234A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5861716A (en) * | 1995-02-20 | 1999-01-19 | Hitachi, Ltd. | Magnetron having a cathode mount with a grooved recess for securely receiving a cathode filament |
| WO2008050619A1 (en) * | 2006-10-27 | 2008-05-02 | Tokyo Electron Limited | Power supply and microwave generator using same |
-
1988
- 1988-06-07 JP JP13997488A patent/JPH01309234A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5861716A (en) * | 1995-02-20 | 1999-01-19 | Hitachi, Ltd. | Magnetron having a cathode mount with a grooved recess for securely receiving a cathode filament |
| WO2008050619A1 (en) * | 2006-10-27 | 2008-05-02 | Tokyo Electron Limited | Power supply and microwave generator using same |
| JP2008113473A (en) * | 2006-10-27 | 2008-05-15 | Tokyo Electron Ltd | Power supply unit and microwave generator employing the same, and computer program |
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