JPS6359233B2 - - Google Patents
Info
- Publication number
- JPS6359233B2 JPS6359233B2 JP19218783A JP19218783A JPS6359233B2 JP S6359233 B2 JPS6359233 B2 JP S6359233B2 JP 19218783 A JP19218783 A JP 19218783A JP 19218783 A JP19218783 A JP 19218783A JP S6359233 B2 JPS6359233 B2 JP S6359233B2
- Authority
- JP
- Japan
- Prior art keywords
- discharge
- reflected wave
- microwave
- reflected
- reference value
- 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
Links
- 238000000034 method Methods 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 description 7
- 238000005070 sampling Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Control Of High-Frequency Heating Circuits (AREA)
Description
【発明の詳細な説明】
この発明は、マイクロ波印加時の放電現象を速
やかに検出する放電検知方法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a discharge detection method for quickly detecting a discharge phenomenon when microwaves are applied.
高出力のマイクロ波を導波管を用いて伝送し、
加熱等の工業用途に用いる場合、空気中のダス
ト、加熱物体からの蒸発物あるいはカーボン等の
物質が存在すると、時としてマイクロ波を吸収
し、この結果急激な発熱現象を生じ、これが原因
となつて気体の放電につながる。すなわち、放電
現象は気体の電離作用、すなわち気体のイオン化
現象であつてプラズマ炎の発生を伴い、これによ
つて放電が発生するとマイクロ波はこのプラズマ
炎により一部反射されるとともに、一部吸収さ
れ、被処理物の加熱ができないばかりか、プラズ
マ炎によつて導波管あるいは加熱器が損傷される
ことになる。また一旦発生した放電状態は、マイ
クロ波を遮断するか、プラズマ炎を冷却しないか
ぎり持続する。このため、放電発生を直ちに検出
し放電を消去させる必要がある。 Transmitting high-power microwaves using a waveguide,
When used for industrial purposes such as heating, the presence of dust in the air, evaporated matter from heated objects, or substances such as carbon may sometimes absorb microwaves, resulting in rapid heat generation, which may be the cause. leading to gas discharge. In other words, the discharge phenomenon is an ionization phenomenon of gas, and is accompanied by the generation of a plasma flame.When a discharge occurs, part of the microwave is reflected by this plasma flame, and part of it is absorbed. Not only will the object to be processed not be heated, but the waveguide or heater will be damaged by the plasma flame. Furthermore, once the discharge state has occurred, it will continue unless the microwave is cut off or the plasma flame is cooled. Therefore, it is necessary to immediately detect the occurrence of discharge and erase the discharge.
この発明はこのような従来の課題の解決のため
になされたものであり、放電発生を迅速かつ確実
に検出することのできる方法を提供するものであ
る。 The present invention has been made to solve these conventional problems, and provides a method that can quickly and reliably detect the occurrence of discharge.
すなわち、この発明は、マイクロ波印加部から
のマイクロ波の反射波を検知し、放電現象に基き
短時間内に生じる反射波強度の急激な変化を、マ
イクロ波の通常の反射状態より定めた基準値と比
較し、反射波量の増加時間が上記基準値より短い
場合を放電現象として検出するようにしたもので
ある。 In other words, the present invention detects the microwave reflected waves from the microwave applying section, and detects the rapid change in the reflected wave intensity that occurs within a short period of time based on the discharge phenomenon. When the increase time of the amount of reflected waves is shorter than the reference value, it is detected as a discharge phenomenon.
以下、この発明の実施例を図面によつて説明す
る。第１図において、マイクロ波発振器１は導波
管２を通して図示しないマイクロ波加熱炉にマイ
クロ波を印加している。導波管２には、マイクロ
波加熱炉に印加した入射波を検出する入射波検出
器４と、マイクロ波加熱炉より反射されに戻つて
くる反射波を検出する反射波検出器５とからなる
方向性結合器３が設けられている。そして、入射
波検出器４、反射波検出器５はパワーモニター６
に接続されている。このパワーモニター６には入
射波、反射波の各強度を表示する表示メータ７，
８が設けられている。適切な加熱操作ができるよ
うに、通常は入射波の強度に応じて反射波の強度
が最小となるように、マイクロ波加熱炉の整合機
および導波管に設けた整合機を調節して、最大の
入射波が得られるように整合を行なう。さらに、
パワーモニター６は反射波レベル信号検出器９が
接続され、上記反射波検出器５による検出信号が
入力されている。 Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a microwave oscillator 1 applies microwaves through a waveguide 2 to a microwave heating furnace (not shown). The waveguide 2 includes an incident wave detector 4 that detects the incident wave applied to the microwave heating furnace, and a reflected wave detector 5 that detects the reflected wave that is reflected back from the microwave heating furnace. A directional coupler 3 is provided. The incident wave detector 4 and the reflected wave detector 5 are connected to a power monitor 6.
It is connected to the. This power monitor 6 includes a display meter 7 that displays each intensity of the incident wave and reflected wave.
8 is provided. In order to perform appropriate heating operations, the matching machine of the microwave heating furnace and the matching machine installed in the waveguide are usually adjusted so that the intensity of the reflected wave is minimized according to the intensity of the incident wave. Matching is performed to obtain the maximum incident wave. moreover,
A reflected wave level signal detector 9 is connected to the power monitor 6, and a detection signal from the reflected wave detector 5 is input thereto.
マイクロ波加熱炉内に放電が発生すると反射波
の強度が短時間内に大きくなる。すなわち、通常
の状態では第２図Ａに示すように反射波強度は
徐々に変化するのに対し、放電発生時にはＢに示
すように反射波強度は急激に変化する。そこで、
この時間変化の状態すなわち、レベル勾配を予め
調べ、放電発生時における反射波の立上り時間よ
り長い時間で、適宜反射波の立上り時間の基準値
を設定しておき、上記反射波レベル信号検知器９
においてパワーモニター６より入力される反射波
の立上り時間における変化を比較させている。そ
して、反射波レベル信号検知器９はマイクロ波発
振器１に接続され、反射波の強度の時間変化、す
なわち、レベル勾配が基準値より大きい場合は、
マイクロ波発振器１に対してリレー信号を発し、
高圧リレー１０を介してマグネツト制御回路１１
を作動させて、一定時間マイクロ波の発振を停止
させるようにしている。 When electric discharge occurs in the microwave heating furnace, the intensity of the reflected wave increases within a short time. That is, in a normal state, the reflected wave intensity changes gradually as shown in FIG. 2A, whereas when a discharge occurs, the reflected wave intensity changes rapidly as shown in FIG. 2B. Therefore,
The state of this time change, that is, the level gradient, is checked in advance, and a reference value for the rise time of the reflected wave is appropriately set at a time longer than the rise time of the reflected wave at the time of occurrence of electric discharge, and the reflected wave level signal detector 9
The changes in the rise time of the reflected waves input from the power monitor 6 are compared in FIG. The reflected wave level signal detector 9 is connected to the microwave oscillator 1, and when the time change in the intensity of the reflected wave, that is, the level gradient is larger than the reference value,
Emit a relay signal to the microwave oscillator 1,
Magnet control circuit 11 via high voltage relay 10
is activated to stop the microwave oscillation for a certain period of time.
このような操作は、例えば第３図に示すような
装置により行なうことができる。同図において、
方向性結合器３により検出された反射波電力はパ
ワーモニター６の表示部に入力されて表示メータ
８に表示される。一方、サンプリング周期毎に反
射波レベル信号検出器９の増幅器９０によつて増
幅され、この信号が放電検出器９にて処理され
る。すなわち、ステツプ９２での１回目のサンプ
リング値LAと、ステツプ９３で所定時間遅延さ
せたステツプ９４での２回目のサンプリング値
LBとの微分値Ｖをステツプ９５で求め、通常反
射波の基準値Vcをステツプ９８で予め測定して
おき、これらをステツプ９６で比較してＶが大き
い場合にはステツプ９９で放電の発生と判断す
る。なお、微分値Ｖは第２図Ｂの点Ａと点Ｂとに
おける反射波強度LAとLBとに基いて求め、基準
値Vcは第２図Ａの点Ａと点Ｂとにおける反射波
強度値に基いて求める。 Such an operation can be performed, for example, using a device as shown in FIG. In the same figure,
The reflected wave power detected by the directional coupler 3 is input to the display section of the power monitor 6 and displayed on the display meter 8. On the other hand, the signal is amplified by the amplifier 90 of the reflected wave level signal detector 9 every sampling period, and this signal is processed by the discharge detector 9. That is, the first sampling value LA in step 92 and the second sampling value in step 94 delayed by a predetermined time in step 93.
The differential value V with respect to LB is determined in step 95, the reference value Vc of the normal reflected wave is measured in advance in step 98, these are compared in step 96, and if V is large, it is determined in step 99 that a discharge has occurred. to decide. The differential value V is obtained based on the reflected wave intensities LA and LB at points A and B in Fig. 2B, and the reference value Vc is the reflected wave intensity value at points A and B in Fig. 2A. Find it based on.
マイクロ波溶融炉内に放電が発生すると上記微
分値Ｖが急激に増大するため基準値Vcを越え、
放電発生の判定がなされる。この判定の信号は若
干の時間遅れを伴つて高圧リレー１０に送られ、
高圧リレー１０をオフにしてマイクロ波を発振さ
せる制御回路１１をオフ状態にし、放電を停止さ
せる。放電が停止すると微分値が基準値より小さ
くなるので、これをステツプ９１で検知して所定
の時間経過後高圧リレー１０を作動させて制御回
路１１をオンにし、マイクロ波の照射を再開させ
る。 When electrical discharge occurs in the microwave melting furnace, the differential value V increases rapidly, exceeding the reference value Vc,
A determination is made as to whether discharge has occurred. This determination signal is sent to the high voltage relay 10 with a slight time delay,
The high voltage relay 10 is turned off, the control circuit 11 for oscillating microwaves is turned off, and the discharge is stopped. When the discharge stops, the differential value becomes smaller than the reference value, so this is detected in step 91, and after a predetermined period of time has elapsed, the high voltage relay 10 is activated to turn on the control circuit 11, and the microwave irradiation is restarted.
以上説明したように、この発明はマイクロ波印
加部で発生する放電によるマイクロ波反射波の立
上り時間を、通常時の反射波の立上り時間と比較
することにより放電の発生を検出するようにした
ものであり、放電の発生を迅速かつ確実に検出す
ることができるものである。 As explained above, the present invention detects the occurrence of a discharge by comparing the rise time of the microwave reflected wave due to the discharge generated in the microwave application section with the rise time of the reflected wave during normal operation. Therefore, the occurrence of discharge can be detected quickly and reliably.
第１図はこの発明を適用する装置の一例を示す
概念図、第２図Ａ，Ｂはそれぞれ通常時と反射波
発生時の反射波強度特性図、第３図は放電検知器
の回路図である。
１……マイクロ波発振器、４……入射波検出
器、５……反射波検出器、６……パワーモニタ
ー、９……放電検出器、１１……制御回路。
Figure 1 is a conceptual diagram showing an example of a device to which the present invention is applied, Figures 2A and B are reflected wave intensity characteristics during normal times and when reflected waves occur, respectively, and Figure 3 is a circuit diagram of a discharge detector. be. DESCRIPTION OF SYMBOLS 1... Microwave oscillator, 4... Incident wave detector, 5... Reflected wave detector, 6... Power monitor, 9... Discharge detector, 11... Control circuit.
Claims (1)
を検知し、放電現象に基き短時間内に生じる反射
波強度の急激な変化を、マイクロ波の通常の反射
状態より定めた基準値と比較し、反射波量の増加
時間が上記基準値より短い場合を放電現象として
検出することを特徴とするマイクロ波印加時の放
電検知方法。1. Detect the microwave reflected waves from the microwave application section, compare the rapid changes in the reflected wave intensity that occur within a short period of time based on the discharge phenomenon with a reference value determined from the normal reflection state of the microwave, A method for detecting discharge when microwaves are applied, characterized in that a case where the increase time of the amount of reflected waves is shorter than the reference value is detected as a discharge phenomenon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19218783A JPS6081794A (en) | 1983-10-13 | 1983-10-13 | Method of detecting discharge at microwave applying time |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19218783A JPS6081794A (en) | 1983-10-13 | 1983-10-13 | Method of detecting discharge at microwave applying time |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6081794A JPS6081794A (en) | 1985-05-09 |
| JPS6359233B2 true JPS6359233B2 (en) | 1988-11-18 |
Family
ID=16287123
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19218783A Granted JPS6081794A (en) | 1983-10-13 | 1983-10-13 | Method of detecting discharge at microwave applying time |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6081794A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020095672A1 (en) * | 2018-11-08 | 2020-05-14 | 日立オートモティブシステムズ株式会社 | Vehicular control device, route distribution device, and vehicular guidance system |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2802840B2 (en) * | 1991-05-14 | 1998-09-24 | 松下電器産業株式会社 | Holding tool |
-
1983
- 1983-10-13 JP JP19218783A patent/JPS6081794A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020095672A1 (en) * | 2018-11-08 | 2020-05-14 | 日立オートモティブシステムズ株式会社 | Vehicular control device, route distribution device, and vehicular guidance system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6081794A (en) | 1985-05-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR890003254A (en) | High frequency heater | |
| JP2004340571A (en) | Automatic thawing control method for microwave oven | |
| US3412227A (en) | Electronic oven protection circuit | |
| Hebner et al. | An experimental study of a parallel‐plate radio‐frequency discharge: Measurements of the radiation temperature and electron density | |
| JPH08167500A (en) | Power source for high frequency plasma generating device | |
| US3238475A (en) | Transmission line arc detecting and eliminating system wherein the energy source is continually disabled and enabled | |
| JPS6359233B2 (en) | ||
| JP2002090328A (en) | Gas detecting alarm device using hot-wire type gas sensor | |
| Saito et al. | Oscillation characteristics of a high power 300 GHz band pulsed gyrotron for use in collective Thomson scattering diagnostics | |
| JP2967656B2 (en) | Distance measuring device | |
| JP3789203B2 (en) | Microwave application equipment | |
| US5012194A (en) | Method testing electron discharge tubes | |
| JP3287041B2 (en) | Control method of plasma processing apparatus | |
| US9977070B2 (en) | Method for inspecting magnetron | |
| Mao et al. | High power microwave test system and simulated experiments for HT-7 | |
| JPH0323304Y2 (en) | ||
| JP2812157B2 (en) | Laser processing equipment | |
| JP2697265B2 (en) | High frequency heating equipment | |
| JPH0343343B2 (en) | ||
| KR200194289Y1 (en) | Burn-in system in test equipment of semiconductor chip | |
| JPH1065242A (en) | Gas laser oscillator | |
| JPH0352279A (en) | Gas laser oscillator | |
| JP3098653B2 (en) | High frequency heating equipment | |
| JPS6052072A (en) | Laser output controlling device | |
| JPH06120589A (en) | Safety device for laser |