JPH0754744B2 - Microwave heating device and microwave heating method - Google Patents
Microwave heating device and microwave heating methodInfo
- Publication number
- JPH0754744B2 JPH0754744B2 JP2257654A JP25765490A JPH0754744B2 JP H0754744 B2 JPH0754744 B2 JP H0754744B2 JP 2257654 A JP2257654 A JP 2257654A JP 25765490 A JP25765490 A JP 25765490A JP H0754744 B2 JPH0754744 B2 JP H0754744B2
- Authority
- JP
- Japan
- Prior art keywords
- microwave
- heated
- reflector
- shaped
- heating
- 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
Links
- 238000010438 heat treatment Methods 0.000 title claims description 55
- 238000000034 method Methods 0.000 title claims description 5
- 239000000919 ceramic Substances 0.000 description 12
- 239000002887 superconductor Substances 0.000 description 10
- 238000005245 sintering Methods 0.000 description 9
- 229910015901 Bi-Sr-Ca-Cu-O Inorganic materials 0.000 description 4
- 238000001354 calcination Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 229910004247 CaCu Inorganic materials 0.000 description 3
- 229910017563 LaCrO Inorganic materials 0.000 description 3
- 229910009203 Y-Ba-Cu-O Inorganic materials 0.000 description 3
- NFYLSJDPENHSBT-UHFFFAOYSA-N chromium(3+);lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Cr+3].[La+3] NFYLSJDPENHSBT-UHFFFAOYSA-N 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 238000012681 fiber drawing Methods 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 229910002480 Cu-O Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 238000005304 joining Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 229910015902 Bi 2 O 3 Inorganic materials 0.000 description 1
- 229910016006 MoSi Inorganic materials 0.000 description 1
- 229910006404 SnO 2 Inorganic materials 0.000 description 1
- 229910002367 SrTiO Inorganic materials 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000003746 solid phase reaction Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Constitution Of High-Frequency Heating (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、陶磁器及びファインセラミックスの焼結、仮
焼、溶融、接合、ファイバー線引き等における加熱手
段、あるいは、乾燥、仮焼、樹脂抜き、焼結等の一連の
加熱工程における加熱手段に係り、詳しくは入射された
マイクロ波を繰り返し往復反射させることにより、往復
反射されたマイクロ波（即ち、周波数範囲として300GHz
程度を上限とするマイクロ波）が集束通過する位置に配
置された被加熱体を加熱させるためのマイクロ波加熱装
置及びマイクロ波加熱方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to heating means for sintering, calcination, melting, joining, fiber drawing, etc. of ceramics and fine ceramics, or drying, calcination, resin removal, It relates to heating means in a series of heating steps such as sintering. Specifically, by repeatedly reflecting the incident microwave back and forth, the microwave reflected back and forth (that is, a frequency range of 300 GHz
The microwave heating device and the microwave heating method for heating an object to be heated which is arranged at a position where microwaves whose upper limit is about the degree) converge and pass through.
（従来の技術） 従来、例えば、陶磁器及びファインセラミックス等を製
造するときの加熱工程に用いられる加熱手段としては、
燃料の燃料加熱、電気ヒータによる伝導及び放射加熱、
赤外線による放射加熱等が採用されており、いずれの加
熱手段においても被加熱体を、その外側から加熱し、熱
伝導により次第に内部まで加熱するものである。(Prior Art) Conventionally, for example, as a heating means used in a heating step when manufacturing ceramics and fine ceramics,
Fuel heating of fuel, conduction and radiant heating by electric heater,
Radiant heating by infrared rays or the like is adopted, and in any heating means, the object to be heated is heated from the outside and gradually heated to the inside by heat conduction.
（発明が解決しようとする課題） 上記従来の加熱手段は、いずれも被加熱体を、その外側
から加熱し、熱伝導により次第に内部まで加熱するもの
であるため、昇温中では常に被加熱体の外側の温度が内
部より高くなることから、被加熱体中に温度勾配が生じ
る。そのため、温度の不均一性による熱応力が被加熱体
に発生し、焼成歪やクラックが発生するという問題があ
った。そのため、特にセラミック動翼のような複雑な形
状のものとか、大型部品の焼成は容易ではなく、焼成歪
やクラックの発生を防ぐためには、昇温速度を低く制限
し、被加熱体の温度勾配を小さくする必要があるため、
加熱時間が長くなり、生産コストが高くなるという問題
があった。(Problems to be Solved by the Invention) In all of the above conventional heating means, the object to be heated is heated from the outside and gradually heated to the inside by heat conduction. Since the temperature of the outside is higher than that of the inside, a temperature gradient occurs in the object to be heated. Therefore, there is a problem that thermal stress is generated in the object to be heated due to the nonuniformity of temperature, and firing strain and cracks are generated. Therefore, it is not easy to fire large-sized parts such as those with complicated shapes such as ceramic blades, and in order to prevent the occurrence of firing strain and cracks, the heating rate should be limited to a low temperature gradient. Is required to be small,
There is a problem that the heating time becomes long and the production cost becomes high.
そこで本発明では、マイクロ波出力手段から出力された
ビーム状のマイクロ波を、曲面状の反射面を有する二つ
の反射体の間で連続的に往復反射させ、その二つの反射
体のほぼ中間位置に配置された被加熱体にマイクロ波を
集束通過させることにより、被加熱体を内部から均一に
加熱し、被加熱体中の温度勾配の発生を抑制するととも
に、急速加熱を可能にさせ、生産性の向上と品質の向上
を計ることを解決すべき技術的課題とするものである。Therefore, in the present invention, the beam-like microwave output from the microwave output means is continuously reflected back and forth between the two reflectors having the curved reflecting surface, and the intermediate position of the two reflectors is almost the middle position. Microwaves are focused and passed through the object to be heated, which is heated in a uniform manner from the inside to suppress the occurrence of temperature gradients in the object and to enable rapid heating. It is a technical issue to be solved to improve productivity and quality.
（課題を解決するための手段） 上記課題解決のための技術的手段は、マイクロ波加熱装
置を、被加熱体を加熱するための所要電力のマイクロ波
をビーム状に出力するビーム状マイクロ波発生器と、前
記ビーム状マイクロ波を端部に開口した入射口から入射
させる箱体と、その箱体の内部に配設され、前記入射口
から入射されたビーム状マイクロ波を曲面状反射面の外
縁部で反射する第１の反射体と、その第１の反射体と対
向する位置に配設され、同第１の反射体の外縁部で反射
された前記ビーム状マイクロ波を受けて反射したあと同
第１の反射体の曲面状反射面との間でビーム状マイクロ
波を連続反射させ、そのビーム状マイクロ波を被加熱体
が配置されるポジションに次第に収束させる曲面状反射
面を有する第２の反射体とを備えた構成にすることであ
る。(Means for Solving the Problem) The technical means for solving the above-mentioned problems is to generate a beam-like microwave that outputs a microwave of a required electric power for heating an object to be heated to a microwave in a microwave heating device. A container, a box body for making the beam-like microwave enter through an entrance opening opened at an end, a beam-like microwave that is arranged inside the box body, and has a curved reflecting surface A first reflector that reflects at the outer edge and a first reflector that is disposed at a position facing the first reflector, and receives and reflects the beam-shaped microwave reflected at the outer edge of the first reflector. A curved reflecting surface that continuously reflects the beam-shaped microwaves between the curved reflecting surface of the first reflector and gradually converges the beam-shaped microwaves to the position where the object to be heated is arranged. In the configuration with two reflectors It is to be.
また、被加熱体を加熱するための所要電力のビーム状マ
イクロ波を第１の反射体の曲面状反射面の外縁部で反射
させ、この反射ビーム状マイクロ波を第２の反射体の曲
面状反射面で受けて反射したあと、第１の反射体の曲面
状反射面と第２の反射体の曲面状反射面との間でビーム
状マイクロ波を連続反射させ、そのビーム状マイクロ波
を、被加熱体が配置されるポジションに次第に収束させ
ることによって被加熱体を均一に加熱することである。Further, the beam-shaped microwave of required power for heating the object to be heated is reflected by the outer edge of the curved reflecting surface of the first reflector, and the reflected beam-shaped microwave is curved by the curved surface of the second reflector. After being received by the reflecting surface and reflected, the beam-like microwave is continuously reflected between the curved reflecting surface of the first reflecting body and the curved reflecting surface of the second reflecting body, and the beam-like microwave is This is to uniformly heat the object to be heated by gradually converging it to the position where the object to be heated is arranged.
（作用） 上記のようなマイクロ波加熱装置及びマイクロ波加熱方
法において、誘電体で形成された陶磁器及びファインセ
ラミックス等の被加熱体がマイクロ波電界中に置かれた
場合、その被加熱体の単位体積当りに吸収される電力Ｐ
は、 Ｐ＝２πｆε0εrtanδ|E|2 ここで、ｆは周波数（GHz） ε0は真空の誘電率（8.86×10-12F/m） εrは被加熱体の比誘電率 tanδは誘電損失 Ｅ（V/m）は内部電界の大きさを示したものである。(Function) In the microwave heating device and the microwave heating method as described above, when a heated object such as ceramics and fine ceramics formed of a dielectric is placed in a microwave electric field, a unit of the heated object Electric power P absorbed per volume
Is P = 2πfε 0 ε r tanδ | E | 2 where f is frequency (GHz) ε 0 is the permittivity of vacuum (8.86 × 10 −12 F / m) ε r is the relative permittivity of the heated object tanδ Is the dielectric loss E (V / m) and represents the magnitude of the internal electric field.
上記式から明らかなように、被加熱体の比誘電率εr、
及び誘電損失tanδの温度特性がマイクロ波加熱プロセ
スのコントロールに重要である。As is clear from the above equation, the relative permittivity ε r of the object to be heated,
The temperature characteristics of dielectric loss tan δ are important for controlling the microwave heating process.
被加熱体の比誘電率εr、及び誘電損失tanδの温度特性
に関して、誘電損失tanδは常温付近における影響が比
誘電率εrに比べて小さく、被加熱体の昇温とともに緩
やかに影響度合いが増加し、ある臨界温度に達すると急
激に大きくなるため、その臨界温度を越えると、被加熱
体におけるマイクロ波エネルギーの吸収がより効率良く
行われるようになり、それによって被加熱体の温度が指
数関数的に上昇する。Regarding the temperature characteristics of the relative permittivity ε r and the dielectric loss tan δ of the object to be heated, the influence of the dielectric loss tan δ at room temperature is smaller than that of the relative permittivity ε r , and the degree of influence gradually increases as the temperature of the object to be heated increases. The temperature of the heated object increases exponentially when it reaches a certain critical temperature, and when it exceeds the critical temperature, the microwave energy is absorbed more efficiently in the heated object, and the temperature of the heated object becomes an exponential value. It rises functionally.
このようにして被加熱体の温度が上昇された場合、最高
温度に達する温度は、被加熱体から発生された熱量と、
伝導及び放射等で拡散される熱量のバランスで決まるた
め、マイクロ波の出力強度により被加熱体の温度制御を
容易に実現することができ、従ってマイクロ波の出力を
調節することにより、従来の高温炉より上限温度を高く
することができる。When the temperature of the object to be heated is increased in this way, the temperature that reaches the maximum temperature is the amount of heat generated from the object to be heated,
Since it is determined by the balance of the amount of heat diffused by conduction and radiation, the temperature of the heated object can be easily controlled by the output intensity of the microwave. The upper limit temperature can be set higher than that of the furnace.
以上のような加熱原理に基づいて前記被加熱体を加熱す
るためのマイクロ波加熱装置によれば、マイクロ波出力
手段からビーム状に出力された所要電力のマイクロ波が
箱体に形成された入射口から入射されると、その入射さ
れたビーム状のマイクロ波は第１の反射体と第２の反射
体の間で連続的に往復反射される。そのビーム状マイク
ロ波を二つの反射体のほぼ中間位置に配置された被加熱
体に集束通過させることにより、被加熱体を内部から均
一に加熱し、被加熱体中の温度勾配の発生を抑制すると
ともに、急速加熱を可能にさせる。According to the microwave heating device for heating the object to be heated based on the heating principle as described above, the microwave of the required power output in the beam form from the microwave output means is incident on the box body. When entering through the mouth, the incident beam-like microwave is continuously reflected back and forth between the first reflector and the second reflector. By focusing and passing the beam-shaped microwaves to the heated object located at the intermediate position between the two reflectors, the heated object is uniformly heated from the inside, and the occurrence of temperature gradient in the heated object is suppressed. And enables rapid heating.
（実施例） 次に、本発明の実施例を図面を参照しながら説明する。(Example) Next, the Example of this invention is described, referring drawings.
第１図は、マイクロ波加熱装置の構成を略体的に示した
構成系統図である。FIG. 1 is a structural system diagram schematically showing the structure of a microwave heating device.
本実施例において、ビーム状マイクロ波発生器１は150K
W、53GHzマイクロ波ビームをパルス状に例えばデューテ
ィ１％の時間率で繰り返し発生し、時間平均出力で1.5K
Wを出力するものである。尚、このビーム状マイクロ波
発生器１は、出力、周波数、及びデューティ％等を所定
の範囲で変化させることができるようになっている。ビ
ーム状マイクロ波発生器１から出力されたマイクロ波ビ
ーム２は、例えば金属材で形成された箱状のマイクロ波
集束装置３に設けられた入射口４から入射される。凹面
鏡状の反射面5Aを有する第１の反射体５は、入射口４か
ら入射されたマイクロ波ビーム２が反射面5Aの上部で反
射するようにマイクロ波集束装置３の内部に固定されて
いる。また、第２の反射体６は、凹面鏡状の反射面6Aを
有しており、反射面5Aと6Aは平行なビームが１点に集束
する放物面形状をしている。そして第１の反射体５、第
２の反射体６それぞれの集束点を被加熱体７付近に合わ
せている。即ち、第２の反射体６は第１の反射体５と中
心光軸を同一にした状態で所要の空間を隔て、第１の反
射体５と対向する位置に配設されており、第１の反射体
５と第２の反射体６の間の空間中央部には、陶磁器及び
ファインセラミックス等の被加熱体７が配置される。In this embodiment, the beam-shaped microwave generator 1 is 150K.
W, 53GHz microwave beam is repeatedly generated in pulse form at a duty ratio of 1%, for example, and time average output is 1.5K
It outputs W. The beam-shaped microwave generator 1 can change the output, frequency, duty ratio, etc. within a predetermined range. The microwave beam 2 output from the beam-shaped microwave generator 1 is incident from an entrance 4 provided in a box-shaped microwave focusing device 3 formed of, for example, a metal material. The first reflector 5 having a concave mirror-shaped reflecting surface 5A is fixed inside the microwave focusing device 3 so that the microwave beam 2 incident from the entrance 4 is reflected at the upper part of the reflecting surface 5A. . The second reflector 6 has a concave mirror-shaped reflecting surface 6A, and the reflecting surfaces 5A and 6A have a parabolic shape in which parallel beams are focused on one point. Then, the focusing points of the first reflector 5 and the second reflector 6 are aligned near the heated body 7. That is, the second reflector 6 is arranged at a position facing the first reflector 5 with the central optical axis being the same as that of the first reflector 5 with a required space therebetween. In the central portion of the space between the reflector 5 and the second reflector 6, a heated object 7 such as a ceramic or fine ceramics is arranged.
以上のように構成されたマイクロ波加熱装置において、
前記入射口４から入射されたパルス状のマイクロ波ビー
ム２が反射面5Aの上部で反射されると、第１図に示すよ
うに第１の反射体５の反射面5Aと第２の反射体６の反射
面6A間で連続的に往復反射され、第１の反射体５の反射
面5Aと第２の反射体６の間の空間中央部を集束通過する
ため、その空間中央部における電磁界強度が５〜10倍に
増大される。そして、その連続反射波は、第１の反射体
５と第２の反射体６の間の空間中央部に置かれた被加熱
体７をマイクロ波が集束通過するため被加熱体７は急速
に加熱される。In the microwave heating device configured as described above,
When the pulsed microwave beam 2 incident from the entrance 4 is reflected on the reflecting surface 5A, as shown in FIG. 1, the reflecting surface 5A of the first reflecting body 5 and the second reflecting body 6 is continuously reflected back and forth between the reflecting surfaces 6A of the first reflector 6 and converges and passes through the central portion of the space between the reflecting surface 5A of the first reflector 5 and the second reflector 6, so that the electromagnetic field in the central portion of the space is Strength is increased 5-10 times. Then, the continuous reflected wave causes the microwaves to converge and pass through the heated body 7 placed in the central portion of the space between the first reflector 5 and the second reflector 6, so that the heated body 7 rapidly moves. Be heated.
以上のようなマイクロ波加熱装置を用いて被加熱体７を
加熱する実験をしたので、その実験について説明する。An experiment for heating the object to be heated 7 using the microwave heating device as described above was conducted, and the experiment will be described.
実験では、被加熱体７として以下の３種類を用いた。In the experiment, the following three types were used as the heated body 7.
（１）ランタンクロマイト （LaCrO3） （２）Bi-Sr-Ca-Cu-O系超電導体 （Bi2Sr2CaCu2OX） （３）Y-Ba-Cu-O系超電導体 （YBa2Cu3O7−δ） 上記それぞれの被加熱体を製作するため、それぞれの被
加熱体の構成元素に当たる出発原料を化学量論比分、秤
量し、計1Kgをボールミルにて16時間湿式粉砕する。そ
のあと乾燥し、乳鉢を用いて加粒状に粗砕する。(1) Lanthanum chromite (LaCrO 3 ) (2) Bi-Sr-Ca-Cu-O system superconductor (Bi 2 Sr 2 CaCu 2 OX) (3) Y-Ba-Cu-O system superconductor (YBa 2 Cu) 3 O 7 −δ) In order to manufacture each of the above-mentioned objects to be heated, the starting materials corresponding to the constituent elements of each object to be heated are weighed in a stoichiometric ratio, and a total of 1 kg is wet pulverized in a ball mill for 16 hours. After that, it is dried and coarsely crushed into particles with a mortar.
加粒状に粗砕された出発原料を、それぞれ1000℃で１時
間、780℃で30時間、900℃で５時間の各条件による固相
反応により、それぞれ原料を合成し、それぞれ16時間、
ボールミルにて粉砕、乾燥したのち、金型を用いて1000
Kg/cm2の成形圧力を加え、直径が12mm、厚みが2.5mmの
円板状のランタンクロマイト（LaCrO3）と、直径が17m
m、厚みが7mmの円板状のBi-Sr-Ca-Cu-O系超電導体（Bi2
Sr2CaCu2OX）と、直径が17mm、厚みが7mmの円板状のY-B
a-Cu-O系超電導体（YBa2Cu3O7−δ）のそれぞれを成形
する。The starting materials that have been crushed into granules are respectively synthesized by solid-phase reaction under the conditions of 1000 ° C. for 1 hour, 780 ° C. for 30 hours, and 900 ° C. for 5 hours, and 16 hours each.
After crushing and drying with a ball mill, 1000 using a mold
A disc-shaped lanthanum chromite (LaCrO 3 ) with a diameter of 12 mm and a thickness of 2.5 mm is applied with a molding pressure of Kg / cm 2 and a diameter of 17 m.
Disc-shaped Bi-Sr-Ca-Cu-O superconductor (Bi 2
Sr 2 CaCu 2 OX) and a disk-shaped YB with a diameter of 17 mm and a thickness of 7 mm
Each of the a-Cu-O superconductors (YBa 2 Cu 3 O 7 −δ) is formed.
上記のようにして製作されたランタンクロマイト（LaCr
O3）と、Bi-Sr-Ca-Cu-O系超電導体（Bi2Sr2CaCu2OX）
と、Y-Ba-Cu-O系超電導体（YBa2Cu3O7−δ）とのそれぞ
れを試料として、第１図に示したマイクロ波加熱装置を
用い、第３図に示すような加熱条件でマイクロ波加熱し
た。Lantern chromite (LaCr
O 3 ) and Bi-Sr-Ca-Cu-O superconductor (Bi 2 Sr 2 CaCu 2 OX)
And a Y-Ba-Cu-O-based superconductor (YBa 2 Cu 3 O 7 -δ) as samples, using the microwave heating device shown in FIG. 1 and heating as shown in FIG. The condition was microwave heated.
第１の試料としてのランタンクロマイト（LaCrO3）の場
合、150KW、53GHzマイクロ波ビームをデューティ比0.5
〜0.7％でパルス状に出力させ、155分間照射加熱した。
第２図は上記加熱過程での昇温状態を放射温度計を用い
て測定した昇温特性図であり、ランタンクロマイトを13
00℃まで加熱し、焼結したことを示している。尚、その
焼結結果は良好であることが確かめられた。In the case of lanthanum chromite (LaCrO 3 ) as the first sample, a 150KW, 53GHz microwave beam was used with a duty ratio of 0.5.
It was pulsed at ~ 0.7% and irradiated and heated for 155 minutes.
FIG. 2 is a temperature rise characteristic diagram in which the temperature rise state in the above heating process was measured by using a radiation thermometer.
It shows that it was heated to 00 ° C and sintered. It was confirmed that the sintering result was good.
第２の試料としてのBi-Sr-Ca-Cu-O系超電導体（Bi2Sr2C
aCu2OX）の場合は、150KW、53GHzマイクロ波ビームをデ
ューティ比0.5〜1.0％でパルス状に出力させ、80分間照
射加熱した。その結果、焼結温度が850℃に達し、その
焼結状態が良好であることが確かめられた。The second sample is a Bi-Sr-Ca-Cu-O system superconductor (Bi 2 Sr 2 C
In the case of aCu 2 OX), a 150 KW, 53 GHz microwave beam was output in a pulse shape with a duty ratio of 0.5 to 1.0% and irradiated and heated for 80 minutes. As a result, it was confirmed that the sintering temperature reached 850 ° C, and the sintering state was good.
第３の試料としてのY-Ba-Cu-O系超電導体（YBa2Cu3O7−
δ）の場合は、150KW、53GHzマイクロ波ビームをデュー
ティ比0.7〜1.0％でパルス状に出力させ、90分間照射加
熱した。その結果、焼結温度が900℃になり、その焼結
状態が良好であることが確かめられた。YBa-Cu-O superconductor as a third sample (YBa 2 Cu 3 O 7 -
In the case of δ), a 150 KW, 53 GHz microwave beam was output in pulses with a duty ratio of 0.7 to 1.0%, and irradiation heating was performed for 90 minutes. As a result, it was confirmed that the sintering temperature reached 900 ° C and that the sintered state was good.
第４図は、第３の試料としてのY-Ba-Cu-O系超電導体（Y
Ba2Cu3O7−δ）を前記手段で５個加熱し、「かさ密度」
と「超電導特性」とを測定したときの結果を示したもの
である。尚、第４図における「かさ密度」測定値は寸法
測定による概算値であり、臨界電流密度は77K（ケルビ
ン）、ゼロ磁場での値を示したものである。Fig. 4 shows the Y-Ba-Cu-O superconductor (Y
Ba 2 Cu 3 O 7 −δ) is heated by 5 pieces by the above means, and “bulk density”
And the "superconducting property" are measured. The “bulk density” measurement value in FIG. 4 is an approximate value obtained by dimension measurement, and the critical current density is 77K (Kelvin), and is a value at zero magnetic field.
第４図に示した結果から明らかなように、５個共、臨界
温度が観測され、超電導体となっていることが確認さ
れ、しかもその内のNo.1の試料では40A/cm2の臨界電流
密度が得られた。As is clear from the results shown in Fig. 4, it was confirmed that all five of them had a critical temperature, and it was confirmed that they were superconductors. In addition, the No. 1 sample among them had a critical temperature of 40 A / cm 2 . The current density was obtained.
以上のような材料以外に、次のような分子式を有する陶
磁器、ファインセラミックスの焼結、仮焼、溶融、接
合、ファイバー線引き、あるいは、乾燥、仮焼、樹脂抜
き、焼結等の一連の加熱工程にも、第１図に示すような
マイクロ波加熱装置を使用することができる。In addition to the above materials, ceramics having the following molecular formula, fine ceramics sintering, calcination, melting, joining, fiber drawing, or a series of heating such as drying, calcination, resin removal, and sintering. A microwave heating device as shown in FIG. 1 can also be used in the process.
Al2O3 SrTiO3 BaTiO3 PLZT PZT ZrO2 ZrO2（PZT） Zu0-Bi2O3 SnO2 SiC Si3N4 MoSi2 即ち、前述の第３図に示した燃料電池用材料、超電導体
の他に、絶縁体、誘電体、圧電体、構造体、半導体等を
作る場合に第１図に示すようなマイクロ波加熱装置を使
用することができる。Al 2 O 3 SrTiO 3 BaTiO 3 PLZT PZT ZrO 2 ZrO 2 (PZT) Zu0-Bi 2 O 3 SnO 2 SiC Si 3 N 4 MoSi 2 That is, the fuel cell material shown in FIG. In addition, the microwave heating device as shown in FIG. 1 can be used when producing an insulator, a dielectric, a piezoelectric body, a structure, a semiconductor, or the like.
次に、第１図に示したマイクロ波加熱装置を使用するこ
とにより、被加熱体をマイクロ波加熱したときの特長を
まとめると次のようになる。Next, by using the microwave heating apparatus shown in FIG. 1, the features when the object to be heated is microwaved are summarized as follows.
（１）被加熱体に直接マイクロ波を吸収させ、被加熱体
を内部から一様に加熱することができるため、複雑な形
状の物でも、あるいは大型の物でも均一に加熱すること
ができる。そのため、被加熱体の温度勾配が低減される
ことから、被加熱体の内部応力が少なくなり、割れとか
破壊を防ぐことができる。(1) Since the object to be heated can directly absorb the microwaves to heat the object to be heated uniformly from the inside, it is possible to uniformly heat an object having a complicated shape or a large object. Therefore, since the temperature gradient of the object to be heated is reduced, the internal stress of the object to be heated is reduced, and cracking or destruction can be prevented.
（２）被加熱体を加熱する場所、即ち発熱場所をエネル
ギー供給装置から空間的に切り離すことができるため、
真空中、加圧室中、大気中、あるいは酸化／還元雰囲気
中での加熱を可能にすることができる。(2) Since the place to heat the object to be heated, that is, the place to generate heat can be spatially separated from the energy supply device,
Heating can be enabled in vacuum, in a pressure chamber, in air, or in an oxidizing / reducing atmosphere.
（３）被加熱体が臨界温度を越えると、マイクロ波吸収
がより効率良く行われるようになることから、臨界温度
を越えて加熱されると、被加熱体の温度上昇が急速にな
り、指数関数的に昇温されるため急速加熱が可能にな
る。そのため、従来の加熱手段に比べて２〜50倍程の急
速加熱が可能になることから、必要最小の成長粒を持つ
緻密体、即ち加速焼結ができる。(3) When the object to be heated exceeds the critical temperature, microwave absorption is more efficiently performed. Therefore, when heated above the critical temperature, the temperature of the object to be heated rises rapidly, and Since the temperature is raised functionally, rapid heating is possible. Therefore, rapid heating of about 2 to 50 times that of the conventional heating means is possible, so that a dense body having the minimum required growth grains, that is, accelerated sintering can be performed.
（４）加熱時間が短縮されるため、エネルギー、工数等
を削減することができることから、生産コストを低減す
ることができる。(4) Since the heating time is shortened, it is possible to reduce energy, man-hours and the like, so that the production cost can be reduced.
（５）被加熱体の比誘電率εrと誘電損失tanδの積に比
例して被加熱体の温度が上昇するため、原理的に温度上
限が無く、大電力の出力装置を用いれば大型の高温電気
炉を構成することができることから、2000℃以上の高温
でセラミックス等を加熱することができる。(5) Since the temperature of the object to be heated rises in proportion to the product of the relative permittivity ε r of the object to be heated and the dielectric loss tan δ, there is no upper temperature limit in principle, and if a high-power output device is used, it becomes large. Since a high-temperature electric furnace can be configured, ceramics or the like can be heated at a high temperature of 2000 ° C. or higher.
（６）反射体を用いることにより、供給されたマイクロ
波を往復反射させ、マイクロ波を被加熱体に集束させる
ことができるため、マイクロ波から熱への変換効率をよ
り向上させることができる。(6) By using the reflector, the supplied microwaves can be reflected back and forth, and the microwaves can be focused on the object to be heated, so that the conversion efficiency from microwaves to heat can be further improved.
また、マイクロ波を集束させることができるため被加熱
体全体ばかりでなく、局部加熱が可能であり、接合部の
溶接、封止、あるいはファイバ線引きなどにおいて、必
要な部分への精密加熱が可能である。In addition, since microwaves can be focused, not only the entire body to be heated but also local heating can be performed, and precise heating to the necessary parts such as welding, sealing of joints, or fiber drawing is possible. is there.
（発明の効果） 以上のように本発明によれば、マイクロ波出力手段から
出力されたビーム状のマイクロ波を、曲面状の反射面を
有する二つの反射体の間で連続的に往復反射させ、その
二つの反射体の間に配置された被加熱体にマイクロ波を
集束通過させるように構成したため、被加熱体を内部か
ら均一に加熱し、被加熱体中の温度勾配の発生を抑制す
るとともに、急速加熱を可能にすることができるように
なり、被加熱体の加熱過程における生産性を向上させる
とともに、被加熱体の品質を向上させることができると
いう効果がある。(Effect of the invention) As described above, according to the present invention, the beam-shaped microwave output from the microwave output means is continuously reflected back and forth between two reflectors having a curved reflecting surface. Since the microwave is focused and passes through the heated body arranged between the two reflectors, the heated body is uniformly heated from the inside, and the generation of the temperature gradient in the heated body is suppressed. At the same time, rapid heating can be enabled, and there is an effect that productivity in the heating process of the object to be heated can be improved and quality of the object to be heated can be improved.
図面は本発明の実施例に係り、第１図はマイクロ波加熱
装置の構成を略体的に示した構成系統図であり、第２図
はマイクロ波加熱装置を用いて被加熱体を加熱したとき
の昇温特性図である。 また、第３図は実験結果を示した表図、第４図は被加熱
体の超電導特性等の計測値を示した表図である。 1:ビーム状マイクロ波発生器 2:マイクロ波ビーム 3:マイクロ波集束装置 4:入射口 5:第１の反射体 6:第２の反射体 7:被加熱体The drawings relate to the embodiment of the present invention, and FIG. 1 is a structural system diagram schematically showing the structure of a microwave heating apparatus, and FIG. 2 heats an object to be heated using the microwave heating apparatus. It is a temperature rising characteristic diagram at this time. Further, FIG. 3 is a table showing the experimental results, and FIG. 4 is a table showing the measured values of the superconducting characteristics of the object to be heated. 1: Beam-shaped microwave generator 2: Microwave beam 3: Microwave focusing device 4: Entrance 5: First reflector 6: Second reflector 7: Object to be heated
───────────────────────────────────────────────────── フロントページの続き (72)発明者 佐藤 元泰 滋賀県滋賀郡志賀町小野朝日１―５―21 (72)発明者 小林 策治 大阪府枚方市御殿山南町４番3944号 (72)発明者 角岡 勉 愛知県刈谷市野田町段留25―８ (72)発明者 東田 豊 愛知県小牧市光ケ丘２丁目18―３ (56)参考文献 特開 昭58−186200（ＪＰ，Ａ) 実開 昭50−68101（ＪＰ，Ｕ) 特公 昭52−6505（ＪＰ，Ｂ２) ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Motoyasu Sato 1-5-21 Ono Asahi, Shiga-machi, Shiga-gun, Shiga Prefecture (72) Inventor Sakuji Kobayashi 4944, Gotenyama-minami-cho, Hirakata-shi, Osaka (72) Invention Author Tsutomu Kadooka 25-8 Dandome, Noda-cho, Kariya City, Aichi Prefecture (72) Inventor Yutaka Higashi 2-18-3, Mitsugaoka, Komaki City, Aichi Prefecture (56) References JP-A-58-186200 (JP, A) 50-68101 (JP, U) JP-B 52-6505 (JP, B2)
Claims (2)
クロ波をビーム状に出力するビーム状マイクロ波発生器
と、前記ビーム状マイクロ波を端部に開口した入射口か
ら入射させる箱体と、その箱体の内部に配設され、前記
入射口から入射されたビーム状マイクロ波を曲面状反射
面の外縁部で反射する第１の反射体と、その第１の反射
体と対向する位置に配設され、同第１の反射体の外縁部
で反射された前記ビーム状マイクロ波を受けて反射した
あと同第１の反射体の曲面状反射面との間でビーム状マ
イクロ波を連続反射させ、そのビーム状マイクロ波を被
加熱体が配置されるポジションに次第に収束させる曲面
状反射面を有する第２の反射体とを備えたことを特徴と
するマイクロ波加熱装置。1. A beam-shaped microwave generator for outputting a microwave of a required electric power for heating an object to be heated in a beam shape, and a box body for injecting the beam-shaped microwave from an entrance opening opened at an end thereof. And a first reflector which is disposed inside the box body and reflects the beam-shaped microwaves incident from the entrance through the outer edge portion of the curved reflecting surface, and which opposes the first reflector. The beam-shaped microwaves, which are arranged at a position and receive the beam-shaped microwaves reflected by the outer edge portion of the first reflector, reflect the beam-shaped microwaves, and then generate a beam-shaped microwave between the curved surface of the first reflector. A microwave heating device comprising: a second reflector having a curved reflection surface that continuously reflects the beam-like microwave and gradually converges the beam-like microwave at a position where the object to be heated is arranged.
ム状マイクロ波を第１の反射体の曲面状反射面の外縁部
で反射させ、この反射ビーム状マイクロ波を第２の反射
体の曲面状反射面で受けて反射したあと、第１の反射体
の曲面状反射面と第２の反射体の曲面状反射面との間で
ビーム状マイクロ波を連続反射させ、そのビーム状マイ
クロ波を、被加熱体が配置されるポジションに次第に収
束させることによって被加熱体を均一に加熱することを
特徴とするマイクロ波加熱方法。2. A beam-shaped microwave of required power for heating an object to be heated is reflected at an outer edge of a curved reflecting surface of the first reflector, and the reflected beam-shaped microwave is reflected by the second reflector. After being received and reflected by the curved reflecting surface of the first reflecting body, the beam-like microwave is continuously reflected between the curved reflecting surface of the first reflecting body and the curved reflecting surface of the second reflecting body. A microwave heating method, wherein a wave is gradually converged on a position where the object to be heated is arranged to uniformly heat the object to be heated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2257654A JPH0754744B2 (en) | 1990-09-26 | 1990-09-26 | Microwave heating device and microwave heating method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2257654A JPH0754744B2 (en) | 1990-09-26 | 1990-09-26 | Microwave heating device and microwave heating method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04137391A JPH04137391A (en) | 1992-05-12 |
| JPH0754744B2 true JPH0754744B2 (en) | 1995-06-07 |
Family
ID=17309255
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2257654A Expired - Fee Related JPH0754744B2 (en) | 1990-09-26 | 1990-09-26 | Microwave heating device and microwave heating method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0754744B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4313806A1 (en) * | 1993-04-27 | 1994-11-03 | Rene Salina | Device for heating materials in a heating chamber which can be irradiated with microwaves, and method for producing ceramic products, in which the raw product (unfinished product) is dried by means of microwaves |
| JP3104585B2 (en) * | 1995-09-18 | 2000-10-30 | 日本電気株式会社 | Microwave heating equipment |
| DE10329412B4 (en) * | 2003-07-01 | 2005-09-22 | Forschungszentrum Karlsruhe Gmbh | Highly modern microwave resonator for thermal processing |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5068101U (en) * | 1973-10-26 | 1975-06-18 | ||
| JPS526505A (en) * | 1975-07-03 | 1977-01-19 | Matsushita Electric Ind Co Ltd | Multichannel audis recording method |
| JPS58186200A (en) * | 1982-04-24 | 1983-10-31 | 株式会社日立製作所 | nuclear fusion device |
-
1990
- 1990-09-26 JP JP2257654A patent/JPH0754744B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04137391A (en) | 1992-05-12 |
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