JP5139136B2

JP5139136B2 - Induction heating device

Info

Publication number: JP5139136B2
Application number: JP2008099942A
Authority: JP
Inventors: 哲美高野; 泰幸池田; 克尚田中; 重信古賀; 大照持永
Original assignee: Fuji Electric Co Ltd; Nippon Steel and Sumitomo Metal Corp
Current assignee: Fuji Electric Co Ltd; Nippon Steel Corp
Priority date: 2007-11-15
Filing date: 2008-04-08
Publication date: 2013-02-06
Anticipated expiration: 2028-04-08
Also published as: JP2009140901A

Description

本発明は誘導加熱装置に関し、特に、誘導加熱装置から発生する磁束を非磁性金属板で遮蔽する方法に適用して好適なものである。 The present invention relates to an induction heating apparatus, and is particularly suitable for application to a method of shielding magnetic flux generated from an induction heating apparatus with a nonmagnetic metal plate.

誘導加熱は、主に亜鉛メッキ鋼板の合金化や塗装鋼板の乾燥などに適用されている。誘導加熱とは、交流電源に接続されたコイルを被加熱物の周辺に配置し、交番磁束により誘起される渦電流のジュール熱で物体を加熱する方法である。金属板の誘導加熱においては、主としてソレノイド方式とトランスバース方式がある。
図８は、ソレノイド方式による誘導加熱方法を示す斜視図である。
図８において、ソレノイド方式では、ソレノイド状に巻回されたコイル１０２の周囲に被加熱物１０１が配置される。そして、コイル１０２に電流を流すことにより、被加熱物１０１の長さ方向に通された磁束１０３を発生させ、この磁束１０３で被加熱物１０１上に誘導電流を発生させることで、被加熱物１０１を加熱する。 Induction heating is mainly applied to alloying galvanized steel sheets and drying painted steel sheets. Induction heating is a method in which a coil connected to an AC power supply is arranged around an object to be heated, and an object is heated by Joule heat of eddy current induced by an alternating magnetic flux. In induction heating of metal plates, there are mainly a solenoid method and a transverse method.
FIG. 8 is a perspective view showing an induction heating method using a solenoid system.
In FIG. 8, in the solenoid system, an object to be heated 101 is disposed around a coil 102 wound in a solenoid shape. Then, by passing an electric current through the coil 102, a magnetic flux 103 passed in the length direction of the object to be heated 101 is generated, and an induction current is generated on the object to be heated 101 by this magnetic flux 103, whereby the object to be heated is generated. 101 is heated.

図９は、トランスバース方式による誘導加熱方法を示す斜視図である。
図９において、トランスバース方式では、対向配置されたコイル１０４、１０４の間に被加熱物１０１が配置される。そして、コイル１０４、１０４に電流を流すことにより、被加熱物１０１の厚さ方向に貫通する磁束１０３を発生させ、この磁束１０３で被加熱物１０１上に誘導電流を発生させることで、被加熱物１０１を加熱する。 FIG. 9 is a perspective view showing an induction heating method using a transverse method.
In FIG. 9, in the transverse method, an object to be heated 101 is arranged between the coils 104 and 104 arranged to face each other. Then, by passing an electric current through the coils 104 and 104, a magnetic flux 103 penetrating in the thickness direction of the object to be heated 101 is generated, and an induction current is generated on the object to be heated 101 by this magnetic flux 103, whereby the object to be heated is heated. The object 101 is heated.

被加熱物１０１が磁性板の場合には、その幅方向の均熱性が高く、効率が良いソレノイド方式が採用されるが、被加熱物１０１が非磁性板の場合には、ソレノイド方式で加熱すると効率が極端に悪くなるので、トランスバース方式が採用される。
なお、被加熱物１０１が非磁性板の場合にソレノイド方式を採用する場合もあるが、この場合には、誘導加熱装置の周波数を高くして、効率の改善が図られる。
ただし、誘導加熱装置の周波数を高くすると、電波障害が発生するなどの問題がある。特に、薄板の被加熱物１０１を加熱する場合には、周波数を極めて高くすることが必要となり、電波障害は一層顕著となる。 When the object to be heated 101 is a magnetic plate, a solenoid system is used that has high temperature uniformity in the width direction and is efficient, but when the object to be heated 101 is a non-magnetic plate, it is heated by a solenoid system. Since the efficiency is extremely poor, the transverse method is adopted.
When the object to be heated 101 is a non-magnetic plate, a solenoid system may be employed. In this case, the efficiency of the induction heating device can be improved by increasing the frequency of the induction heating device.
However, when the frequency of the induction heating device is increased, there is a problem that radio wave interference occurs. In particular, when heating the thin object to be heated 101, it is necessary to make the frequency extremely high, and the radio wave interference becomes more remarkable.

図１０は、従来の誘導加熱装置の概略構成を示す斜視図である。
図１０において、誘導加熱装置には、商用電源から出力された電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置６、周波数変換装置６とソレノイド式コイル２とをインピーダンス整合させる整合装置５、被加熱物１を誘導加熱する磁束を発生させるソレノイド式コイル２が設けられ、ソレノイド式コイル２はコイル架台９上に配置されている。
上述の周波数変換装置６、整合装置５およびソレノイド式コイル２は導体７を介して順次接続され、ソレノイド式コイル２の上流側には前処理設備１３、ソレノイド式コイル２の下流側には後処理設備１４が配置されている。
ここで、上述の上流側および下流側とは、何れも被加熱物１の搬送方向に着目した場合での表記であり、以下同様である。 FIG. 10 is a perspective view showing a schematic configuration of a conventional induction heating apparatus.
10, the induction heating device includes a frequency conversion device 6 that converts the frequency of the voltage output from the commercial power source into a frequency suitable for induction heating, and a matching device that impedance matches the frequency conversion device 6 and the solenoid coil 2. 5. A solenoid type coil 2 for generating a magnetic flux for induction heating the object to be heated 1 is provided, and the solenoid type coil 2 is arranged on a coil mount 9.
The frequency converter 6, the matching device 5, and the solenoid coil 2 described above are sequentially connected via a conductor 7. The pretreatment equipment 13 is upstream of the solenoid coil 2 and the post treatment is downstream of the solenoid coil 2. Equipment 14 is arranged.
Here, the above-described upstream side and downstream side are notations when attention is paid to the conveyance direction of the article 1 to be heated, and so on.

周波数変換装置６から出力された交流は整合装置５を介してソレノイド式コイル２に印加され、ソレノイド式コイル２に交番磁束が発生される。上流側の前処理設備１３から搬出された被加熱物１はソレノイド式コイル２に搬送され、ソレノイド式コイル２で誘導加熱された後、下流側の処理設備１４へと搬送される。
この図１０の誘導加熱装置では、前処理設備１３、後処理設備１４やソレノイド式コイル２の中に被加熱物１があるときを除き、被加熱物１の外部周辺部には被加熱物１を被うものが何もない。
また、ソレノイド式コイル２は碍子（図示せず）などで支持され架台９上に固定され、その外部周辺部にはソレノイド式コイル２を被うものは何もない。
尤も、場合によっては、コイル２の外部周辺部は絶縁性の板（図示せず）で被われることがある。 The alternating current output from the frequency converter 6 is applied to the solenoid coil 2 via the matching device 5, and an alternating magnetic flux is generated in the solenoid coil 2. The object to be heated 1 carried out from the upstream pretreatment facility 13 is transported to the solenoid coil 2, is induction-heated by the solenoid coil 2, and is then transported to the downstream processing facility 14.
In the induction heating apparatus shown in FIG. 10, the object 1 to be heated is placed on the outer periphery of the object 1 to be heated except when the object 1 is in the pretreatment facility 13, the posttreatment facility 14, and the solenoid coil 2. There is nothing to wear.
The solenoid coil 2 is supported by a lever (not shown) or the like and fixed on the gantry 9, and there is nothing that covers the solenoid coil 2 at the outer periphery.
However, in some cases, the outer peripheral portion of the coil 2 may be covered with an insulating plate (not shown).

また一方、周波数変換装置６、整合装置５およびソレノイド式コイル２を順次接続する導体７の外部周辺部にも、導体７を被うものが何もない。
但し、場合によっては、ソレノイド式コイル２と同様に導体７の外部周辺部は絶縁性の板（図示せず）で被われることがある。
上述のような従来の誘導加熱装置において、電波障害を軽減する方策として、誘導加熱装置を磁性体でシールドすることにより、磁界の漏洩を防ぐ方法がある。
このような従来の方法では、磁性体としては電磁鋼鈑やフェライトなどが適用されるが、電磁鋼鈑では、数十ｋＨｚ以上の周波数で鉄損が大きくなる。 On the other hand, there is nothing that covers the conductor 7 in the outer peripheral portion of the conductor 7 that sequentially connects the frequency converter 6, the matching device 5, and the solenoid coil 2.
However, in some cases, like the solenoid coil 2, the outer peripheral portion of the conductor 7 may be covered with an insulating plate (not shown).
In the conventional induction heating apparatus as described above, as a measure for reducing radio wave interference, there is a method of preventing leakage of a magnetic field by shielding the induction heating apparatus with a magnetic material.
In such a conventional method, an electromagnetic steel plate, ferrite, or the like is applied as the magnetic material, but the iron loss increases at a frequency of several tens of kHz or more in the electromagnetic steel plate.

一方、フェライトは高価なため、ソレノイド式コイル２の周囲を被うと、大量のフェライトが必要となり、設備コストが高くなると共に、非磁性金属板に比べると重たく、メンテナンス性に欠ける。
また、電波障害を軽減する他の方法として、ソレノイド式コイル２に対向してその外部周辺部を非磁性金属板で遮蔽して磁束の漏洩を防止し、ソレノイド式コイル２から発生する雑音電界強度を低減し、且つ、ソレノイド式コイル２に導体７を介して電気的に接続されている整合装置５および周波数変換装置６についても、ソレノイド式コイル２と同様に導体７を含めてその外部周辺部を非磁性金属板で遮蔽して磁束の漏洩を防止し、整合装置５、周波数変換装置６および導体７から発生する雑音電界強度を低減する方法がある。 On the other hand, since ferrite is expensive, covering the periphery of the solenoid coil 2 requires a large amount of ferrite, which increases equipment costs and is heavier than a non-magnetic metal plate and lacks maintenance.
Further, as another method for reducing the radio interference, the outer peripheral portion of the solenoid coil 2 is opposed to the solenoid coil 2 with a nonmagnetic metal plate to prevent magnetic flux leakage, and the noise electric field intensity generated from the solenoid coil 2 As for the matching device 5 and the frequency conversion device 6 that are electrically connected to the solenoid coil 2 via the conductor 7, the external peripheral portion including the conductor 7 as well as the solenoid coil 2 is reduced. Is shielded with a non-magnetic metal plate to prevent magnetic flux leakage, and the noise electric field intensity generated from the matching device 5, the frequency converter 6 and the conductor 7 is reduced.

しかし、誘導加熱装置を構成する周波数変換装置６、整合装置５およびソレノイド式コイル２を順次電気的に接続する導体７を被う金属板には、交番磁束により渦電流が誘起され電流が流れる。
このため、金属板に電位が発生し、誘起電流が大きい場合には、金属板の電位が高くなることから、金属板に触れると、感電を引き起こす恐れがある。具体的には、電位の高い金属板に触れると、人体に接触電流が流れ、そのジュール熱により熱傷を負うとことがある。この時、人体の神経に対する感電に関しては高周波、特に数１０ｋＨｚを超える周波数においては、表皮効果および人体内の電気伝導が電解質を介することから、感知する閾値が高いことが知られている。内部の神経、特に重要な心臓制御の神経に作用した時に生じる心室細動の限界はジュール熱による熱傷の限界よりも高い。 However, an eddy current is induced by the alternating magnetic flux on the metal plate that covers the conductor 7 that sequentially connects the frequency converter 6, the matching device 5, and the solenoid coil 2 that constitute the induction heating device, and the current flows.
For this reason, when a potential is generated in the metal plate and the induced current is large, the potential of the metal plate is increased. Therefore, touching the metal plate may cause an electric shock. Specifically, when a high-potential metal plate is touched, a contact current flows through the human body, and the Joule heat may cause burns. At this time, regarding the electric shock to the nerve of the human body, it is known that at a high frequency, particularly at a frequency exceeding several tens of kHz, the threshold value for sensing is high because the skin effect and the electric conduction in the human body are via the electrolyte. The limit of ventricular fibrillation that occurs when acting on internal nerves, particularly important cardiac control nerves, is higher than the limit of Joule fever burns.

このような感電を防止するために、例えば特許文献１では、誘導加熱コイルと被加熱物との間に静電シールド体を設け、その静電シールド体の通電状態を検知する検知手段を設け、その検知手段の検知結果に基づき、通電状態が悪化すると、誘導加熱コイルの出力を低減又は停止するよう制御する誘導加熱装置が提案されている。
また、特許文献２では、周波数変換装置６、整合装置５およびソレノイド式コイル２を順次電気的に接続する導体７と、導体７を被う金属板との距離を大きくすることで、金属板に誘起される電流を小さくし、感電を防ぐ方法が提案されている。
特開２００５−５２７３号公報特開平８−２０８２３号公報 In order to prevent such an electric shock, for example, in Patent Document 1, an electrostatic shield body is provided between the induction heating coil and the object to be heated, and a detection means for detecting the energization state of the electrostatic shield body is provided. There has been proposed an induction heating device that controls to reduce or stop the output of the induction heating coil when the energized state deteriorates based on the detection result of the detection means.
Further, in Patent Document 2, a metal plate is obtained by increasing the distance between a conductor 7 that sequentially electrically connects the frequency converter 6, the matching device 5, and the solenoid coil 2 and a metal plate that covers the conductor 7. Methods have been proposed for reducing the induced current and preventing electric shock.
JP 2005-5273 A JP-A-8-20823

しかしながら、特許文献１に開示された技術では、感電の予防には効果があるが、誘導加熱コイルの出力を低減又は停止するため、所望の加熱ができなくなったり、中断したりするという問題があった。
また、特許文献２に開示された技術では、導体と金属板との距離を大きくするため、誘導加熱装置の外形寸法が大きくなることが避けられず、従って、設置面積の増大が不可避であり、当然ながらコストが嵩むことになる。
一方、金属板の代わりにプラスチック、木材等の絶縁物でコイル等を被い、感電を防ぐことも考えられるが、絶縁物には交番磁束の遮蔽効果がないため、人体に対して直接高周波磁界が侵入し、磁界被爆が生じると共に、電波障害の原因になる。
そこで、本発明の目的は、ソレノイド式コイルを用いて周波数を上げて誘導加熱を行った場合においても、外形寸法を増大させることなく、電波障害を抑制すると共に、感電を防止しつつ、所望の加熱を実現することが可能な誘導加熱装置を提供することである。 However, although the technique disclosed in Patent Document 1 is effective in preventing electric shock, there is a problem that desired heating cannot be performed or interrupted because the output of the induction heating coil is reduced or stopped. It was.
Further, in the technique disclosed in Patent Document 2, in order to increase the distance between the conductor and the metal plate, it is inevitable that the external dimension of the induction heating device is increased, and therefore an increase in the installation area is inevitable. Of course, the cost increases.
On the other hand, it may be possible to prevent electric shock by covering the coil with an insulator such as plastic or wood instead of a metal plate, but the insulator does not have the effect of shielding alternating magnetic flux, so the high-frequency magnetic field is directly applied to the human body. Enters, causing magnetic field exposure and causing radio interference.
Therefore, an object of the present invention is to suppress a radio wave interference and prevent an electric shock without increasing an outer dimension, even when induction heating is performed by increasing the frequency using a solenoid type coil, while preventing an electric shock. To provide an induction heating device capable of realizing heating.

上述した課題を解決するために、本願では次に列記するような技術を提案する。
本発明の請求項１の誘導加熱装置は：
被加熱物を誘導加熱する磁束を発生させるコイルと、前記コイルに印加される電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置と、前記周波数変換装置と前記コイルとを電気的に整合させる整合装置と、前記周波数変換装置、前記整合装置および前記コイルを順次接続する導体と、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体の外部周辺部にそれぞれ配置され、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体をそれぞれ被う非磁性金属板と、前記周波数変換装置、前記整合装置および前記コイルのそれぞれの金属筐体および前記非磁性金属板を互いに電気的に接続すると共に、接地された幅３０ｍｍ以上の非磁性金属帯とを備え、前記金属筐体および前記非磁性金属板と電気的に接続することを特徴とする。 In order to solve the above-described problems, the present application proposes the following techniques.
The induction heating device according to claim 1 of the present invention is:
A coil that generates a magnetic flux for induction heating of an object to be heated, a frequency converter that converts a frequency of a voltage applied to the coil to a frequency suitable for induction heating, and the frequency converter and the coil electrically A matching device for matching, a conductor for sequentially connecting the frequency converter, the matching device, and the coil; and the frequency converter, the matching device, the coil, and an outer peripheral portion of the conductor, and the frequency converter Device, the matching device, the nonmagnetic metal plate covering the coil and the conductor, and the frequency converter, the matching device, the metal housing of the coil and the nonmagnetic metal plate are electrically connected to each other. And a grounded nonmagnetic metal strip having a width of 30 mm or more and electrically connected to the metal casing and the nonmagnetic metal plate. It is characterized in.

本発明の請求項２の誘導加熱装置は：
被加熱物を誘導加熱する磁束を発生させるコイルと、前記コイルに印加される電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置と、前記周波数変換装置と前記コイルとを電気的に整合させる整合装置と、前記周波数変換装置、前記整合装置および前記コイルを順次接続する導体と、前記被加熱物の搬入方向における前記コイルの上流側に設置された、金属筐体を有して内部を前記被加熱物が通過する前処理設備と、前記被加熱物の搬出方向における前記コイルの下流側に設置された、金属筐体を有して内部を前記被加熱物が通過する後処理設備と、少なくとも前記導体の外部周辺部に配置されてこの導体を被い相互に電気的に接続された第１の非磁性金属板と、前記コイルに搬入される被加熱物が被われるように前記コイルと前記前処理設備との間の境界部に配置され、前記第１の非磁性金属板と電気的に接続された第２の非磁性金属板と、前記コイルから搬出される被加熱物が被われるように前記コイルと前記後処理設備との間の境界部に配置され、前記第１の非磁性金属板と電気的に接続された第３の非磁性金属板とを備えることを特徴とする。 The induction heating device according to claim 2 of the present invention is:
A coil that generates a magnetic flux for induction heating of an object to be heated, a frequency converter that converts a frequency of a voltage applied to the coil to a frequency suitable for induction heating, and the frequency converter and the coil electrically A matching device for matching, a conductor for sequentially connecting the frequency conversion device, the matching device and the coil, and a metal casing installed on the upstream side of the coil in the carry-in direction of the object to be heated. A pre-processing facility through which the heated object passes, and a post-processing facility installed downstream of the coil in the unloading direction of the heated object and having a metal casing through which the heated object passes The first non-magnetic metal plate disposed at least on the outer peripheral portion of the conductor and covering the conductor and electrically connected to each other, and the heated object carried in the coil coil A second nonmagnetic metal plate disposed at a boundary between the pretreatment facility and electrically connected to the first nonmagnetic metal plate, and an object to be heated carried out of the coil are covered. And a third nonmagnetic metal plate disposed at a boundary between the coil and the post-processing equipment and electrically connected to the first nonmagnetic metal plate.

本発明の請求項３の誘導加熱装置は：
被加熱物を誘導加熱する磁束を発生させるコイルと、前記コイルに印加される電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置と、前記周波数変換装置と前記コイルとを電気的に整合させる整合装置と、前記周波数変換装置、前記整合装置および前記コイルを順次接続する導体と、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体の外部周辺部にそれぞれ配置され、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体をそれぞれ被う非磁性金属板と、前記被加熱物の搬入方向における前記コイルの上流側に設置された前処理設備と、前記被加熱物の搬出方向における前記コイルの下流側に設置された後処理設備と、少なくとも前記導体の外部周辺部に配置されてこの導体を被い相互に電気的に接続された第１の非磁性金属板と、前記コイルに搬入される被加熱物が被われるように前記コイルと前記前処理設備との間の境界部に配置され、前記第１の非磁性金属板および前記前処理設備の金属筐体と電気的に接続された第２の非磁性金属板と、前記コイルから搬出される被加熱物が被われるように前記コイルと前記後処理設備との間の境界部に配置され、前記第１の非磁性金属板および前記後処理設備の金属筐体と電気的に接続された第３の非磁性金属板と、前記周波数変換装置、前記整合装置および前記コイルのそれぞれの金属筐体および前記非磁性金属板を互いに電気的に接続すると共に、接地された幅３０ｍｍ以上の非磁性金属帯とを備え、前記金属筐体および前記非磁性金属板と電気的に接続することを特徴とする。 The induction heating device according to claim 3 of the present invention is:
A coil that generates a magnetic flux for induction heating of an object to be heated, a frequency converter that converts a frequency of a voltage applied to the coil to a frequency suitable for induction heating, and the frequency converter and the coil electrically A matching device for matching, a conductor for sequentially connecting the frequency converter, the matching device, and the coil; and the frequency converter, the matching device, the coil, and an outer peripheral portion of the conductor, and the frequency converter Apparatus, matching device, nonmagnetic metal plate covering coil and conductor respectively, pretreatment equipment installed upstream of coil in loading direction of heated object, and unloading direction of heated object The post-processing equipment installed on the downstream side of the coil in the coil is disposed at least on the outer periphery of the conductor and covers this conductor to make electrical contact with each other. The first nonmagnetic metal plate is disposed at a boundary portion between the coil and the pretreatment facility so as to cover the heated first nonmagnetic metal plate and the heated object carried into the coil. And a second non-magnetic metal plate electrically connected to the metal casing of the pretreatment facility, and between the coil and the posttreatment facility so as to cover a heated object carried out of the coil A third non-magnetic metal plate disposed at a boundary and electrically connected to the first non-magnetic metal plate and a metal casing of the post-processing facility; the frequency converter; the matching device; and the coil. Each of the metal casing and the nonmagnetic metal plate are electrically connected to each other, and a grounded nonmagnetic metal band having a width of 30 mm or more is provided, and the metal casing and the nonmagnetic metal plate are electrically connected to each other. It is characterized by connecting.

本発明の請求項４の誘導加熱装置は：
被加熱物を誘導加熱する磁束を発生させるコイルと、前記コイルに印加される電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置と、前記周波数変換装置と前記コイルとを電気的に整合させる整合装置と、前記周波数変換装置、前記整合装置および前記コイルを順次接続する導体と、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体の外部周辺部にそれぞれ配置され、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体をそれぞれ被うと共に、互いに電気的に接続された第１の非磁性金属板と、前記被加熱物が前記コイルの中空部を通して搬送されることを許容するための開口部を有すると共に該開口部の幅寸法または高さ寸法のいずれか大きい方の寸法以上の長さにわたり当該搬送方向に略沿って前記被加熱物を被い且つ前記第１の非磁性金属板に電気的に接続された第２の被磁性金属板とを備えることを特徴とする。 The induction heating device according to claim 4 of the present invention is:
A coil that generates a magnetic flux for induction heating of an object to be heated, a frequency converter that converts a frequency of a voltage applied to the coil to a frequency suitable for induction heating, and the frequency converter and the coil electrically A matching device for matching, a conductor for sequentially connecting the frequency converter, the matching device, and the coil; and the frequency converter, the matching device, the coil, and an outer peripheral portion of the conductor, and the frequency converter A first non-magnetic metal plate that covers the device, the alignment device, the coil, and the conductor, and is electrically connected to each other, and allows the object to be heated to be conveyed through the hollow portion of the coil. Substantially along the conveying direction over a length equal to or greater than the larger of the width or height of the opening. Wherein characterized in that it comprises a second of the magnetic metal plate which is electrically connected to the object to be heated a covered and said first non-magnetic metal plate.

本発明の請求項５の誘導加熱装置は：
被加熱物を誘導加熱する磁束を発生させるコイルと、前記コイルに印加される電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置と、前記周波数変換装置と前記コイルとを電気的に整合させる整合装置と、前記周波数変換装置、前記整合装置および前記コイルを順次接続する導体と、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体の外部周辺部にそれぞれ配置され、前記周波数変換装置、前記整合装置、前記コイルおよび前記導体をそれぞれ被う第１の非磁性金属板と、前記周波数変換装置、前記整合装置および前記コイルのそれぞれの金属筐体および前記第１の非磁性金属板を互いに電気的に接続し、前記被加熱物が前記コイルの中空部を通して搬送されることを許容するための開口部を有すると共に該開口部の幅寸法または高さ寸法のいずれか大きい方の寸法以上の長さにわたり当該搬送方向に略沿って前記被加熱物を被い且つ前記第１の非磁性金属板に電気的に接続された第２の非磁性金属板と、前記金属筐体および前記非磁性金属板と電気的に接続されると共に接地された幅３０ｍｍ以上の非磁性金属帯とを備えることを特徴とする。
本発明の請求項６に記載の誘導加熱装置は：
請求項１から５のいずれか一項の誘導加熱装置において、運転周波数が１００ｋＨｚから１ＭＨｚの範囲、電力が１００ｋＷ以上であることを特徴とする。 The induction heating device according to claim 5 of the present invention is:
A coil that generates a magnetic flux for induction heating of an object to be heated, a frequency converter that converts a frequency of a voltage applied to the coil to a frequency suitable for induction heating, and the frequency converter and the coil electrically A matching device for matching, a conductor for sequentially connecting the frequency converter, the matching device, and the coil; and the frequency converter, the matching device, the coil, and an outer peripheral portion of the conductor, and the frequency converter A first nonmagnetic metal plate covering the device, the matching device, the coil and the conductor, and a metal housing and the first nonmagnetic metal plate of the frequency converter, the matching device and the coil, respectively. Are electrically connected to each other and have an opening for allowing the object to be heated to be conveyed through the hollow portion of the coil. Covering the object to be heated substantially along the transport direction over a length equal to or greater than the width dimension or height dimension of the section, and electrically connected to the first non-magnetic metal plate A second nonmagnetic metal plate, and a nonmagnetic metal band having a width of 30 mm or more that is electrically connected to the metal casing and the nonmagnetic metal plate and grounded.
The induction heating apparatus according to claim 6 of the present invention is:
The induction heating apparatus according to any one of claims 1 to 5 , wherein an operating frequency is in a range of 100 kHz to 1 MHz, and power is 100 kW or more.

以上説明したように、本発明によれば、互いに電気的に接続された非磁性金属板で周波数変換装置、整合装置、コイルおよび導体をそれぞれ被うことで、誘起電流が大きい場合においても、非磁性金属板の電位差を低減しつつ、磁界の漏洩を防ぐことができる。
このため、ソレノイドコイルによる鋼板の誘導加熱、特にその一例としての高い周波数での鋼鈑の誘導加熱において、該鋼板の幅方向の均熱性に優れ、且つ、効率の高い薄鋼板の誘導加熱を実現することができる。
さらに、電波障害を抑制し、感電のおそれが無い安全な誘導加熱装置を実現することができる。 As described above, according to the present invention, the non-magnetic metal plates electrically connected to each other cover the frequency conversion device, the matching device, the coil, and the conductor, so that even when the induced current is large, Leakage of the magnetic field can be prevented while reducing the potential difference of the magnetic metal plate.
For this reason, inductive heating of steel sheets by solenoid coils, especially in the induction heating of steel sheets at high frequency as an example, realizes induction heating of thin steel sheets with excellent heat uniformity in the width direction of the steel sheets and high efficiency. can do.
Furthermore, it is possible to realize a safe induction heating device that suppresses radio wave interference and does not cause a risk of electric shock.

さらにまた、ソレノイドコイルによる非鉄金属薄板の誘導加熱においても、薄板の幅方向の均熱性に優れ、効率の高い非鉄金属薄板の誘導加熱実現することができる。
この非鉄金属薄板の誘導加熱の場合においても、さらに、電波障害を抑制し、感電のおそれが無い安全な誘導加熱装置を実現することができる。
特に、誘導加熱装置の周波数が１００ｋＨｚ〜１ＭＨｚの場合であっても、ラジオの放送電波などへの障害を抑制し、且つ、感電のおそれが無い安全な誘導加熱装置を実現することができる。
さらにまた、従来の技術では電波障害が大きくなるおそれがあった１００kW以上の大電力の誘導加熱装置である場合においても、電波障害を抑制し、感電のおそれの無い安全な誘導加熱装置を実現することができる。 Furthermore, in induction heating of a non-ferrous metal thin plate by a solenoid coil, it is possible to achieve induction heating of the non-ferrous metal thin plate that is excellent in heat uniformity in the width direction of the thin plate and high in efficiency.
Even in the case of induction heating of this non-ferrous metal thin plate, it is possible to further realize a safe induction heating device that suppresses radio wave interference and does not cause electric shock.
In particular, even when the frequency of the induction heating device is 100 kHz to 1 MHz, it is possible to realize a safe induction heating device that suppresses disturbances to radio broadcast waves and the like and has no fear of electric shock.
Furthermore, even in the case of a high-power induction heating apparatus of 100 kW or more, in which there has been a risk of increasing radio wave interference in the conventional technology, a radio wave interference is suppressed and a safe induction heating apparatus without fear of electric shock is realized. be able to.

以下、本発明の実施形態に係る誘導加熱装置について図面を参照しながら説明する。
図１は、本発明の一実施形態としての誘導加熱装置の概略構成を示す電気主回路単線結線図である。
また、図２は、本発明の一実施形態としての誘導加熱装置の概略構成を示す斜視図である。
図１および図２において、誘導加熱装置には、商用電源１から出力された電圧の周波数を誘導加熱に適した周波数に変換する周波数変換装置６、周波数変換装置６とソレノイド式コイル２とをインピーダンス整合させる整合装置５、被加熱物１００を誘導加熱する磁束を発生させるソレノイド式コイル２が設けられている。 Hereinafter, an induction heating apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an electric main circuit single line connection diagram showing a schematic configuration of an induction heating apparatus as one embodiment of the present invention.
FIG. 2 is a perspective view showing a schematic configuration of an induction heating apparatus as one embodiment of the present invention.
1 and 2, the induction heating device includes a frequency converter 6 that converts the frequency of the voltage output from the commercial power source 1 into a frequency suitable for induction heating, the frequency converter 6 and the solenoid coil 2 having impedance. An alignment device 5 for alignment and a solenoid coil 2 for generating a magnetic flux for induction heating the object to be heated 100 are provided.

周波数変換装置６には、交流を直流に変換する整流器３、直流を交流に変換するインバータ４、整合用変圧器Ｔが設けられると共に、整合装置５には、整合用コンデンサＣが設けられている。
インバータ４として、ＭＯＳＦＥＴ素子などを使用した半導体式周波数変換装置や真空管式周波数変換装置を適用可能である。
図２を参照して理解されるように、周波数変換装置６、整合装置５およびソレノイド式コイル２は導体７を介して順次接続されている。 The frequency converter 6 is provided with a rectifier 3 that converts alternating current into direct current, an inverter 4 that converts direct current into alternating current, and a matching transformer T, and the matching device 5 is provided with a matching capacitor C. .
As the inverter 4, a semiconductor frequency converter or a vacuum tube frequency converter using a MOSFET element or the like is applicable.
As can be understood with reference to FIG. 2, the frequency converter 6, the matching device 5, and the solenoid coil 2 are sequentially connected via a conductor 7.

被加熱物１００はソレノイド式コイル２の中空部を通して搬送されるが、この被加熱物１００の搬入方向におけるソレノイド式コイル２の上流側に前処理設備１３が設置され、さらに、被加熱物１００の搬出方向におけるソレノイド式コイル２の下流側に後処理設備１４が設置されている。なお、導体７は、銅ブスバーやアルミブスバー等で構成することができる。
また、導体７の外部周辺部には導体７を被う非磁性金属板８が設けられると共に、ソレノイド式コイル２の外部周辺部にはソレノイド式コイル２を被う非磁性金属板１５が設けられている。
非磁性金属板８および非磁性金属板１５は、例えば図示のような形状および配置を採ることができるが、これは一つの例である。 The object to be heated 100 is conveyed through the hollow portion of the solenoid coil 2. A pretreatment facility 13 is installed upstream of the solenoid coil 2 in the loading direction of the object to be heated 100. A post-processing facility 14 is installed on the downstream side of the solenoid coil 2 in the carry-out direction. The conductor 7 can be formed of a copper bus bar, an aluminum bus bar, or the like.
A nonmagnetic metal plate 8 covering the conductor 7 is provided on the outer peripheral portion of the conductor 7, and a nonmagnetic metal plate 15 covering the solenoid coil 2 is provided on the outer peripheral portion of the solenoid coil 2. ing.
The nonmagnetic metal plate 8 and the nonmagnetic metal plate 15 can take, for example, shapes and arrangements as illustrated, but this is one example.

更に、ソレノイド式コイル２と前処理設備１３との境界部には被加熱物１００を被う非磁性金属板１１が設けられ、ソレノイド式コイル２と後処理設備１４との境界部には被加熱物１００を被う非磁性金属板１２が設けられている。
上述の非磁性金属板８、１１、１２、１５は互いに電気的に接続されると共に、ソレノイド式コイル２、整合装置５、周波数変換装置６および導体７のそれぞれの金属筐体と電気的に接続され、さらに前処理設備１３および後処理設備１４のそれぞれの金属筐体とも電気的に接続されている。 Further, a nonmagnetic metal plate 11 that covers the object to be heated 100 is provided at the boundary between the solenoid coil 2 and the pretreatment facility 13, and the boundary between the solenoid coil 2 and the post treatment facility 14 is heated. A nonmagnetic metal plate 12 that covers the object 100 is provided.
The above-mentioned nonmagnetic metal plates 8, 11, 12, and 15 are electrically connected to each other and electrically connected to the respective metal housings of the solenoid coil 2, the matching device 5, the frequency converter 6 and the conductor 7. Furthermore, the respective metal housings of the pretreatment facility 13 and the posttreatment facility 14 are also electrically connected.

なお、非磁性金属板８、１１、１２、１５を構成する材料としては、電気抵抗が小さく、かつ、加工性の良好な金属であればよいが、銅をベースとするものが特に望ましい。
図１の商用電源１から出力された交流は整流器３で直流に変換された後、インバータ４に入力される。このインバータ４で所望の周波数の交流に変換され、整合用変圧器Ｔを経由し整合用コンデンサＣで電気的な整合がとられ、ソレノイド式コイル２に印加され、この結果ソレノイド式コイル２に交番磁束が発生される。 In addition, as a material which comprises the nonmagnetic metal plates 8, 11, 12, and 15, any metal having low electrical resistance and good workability may be used, but a material based on copper is particularly desirable.
The alternating current output from the commercial power source 1 in FIG. 1 is converted into direct current by the rectifier 3 and then input to the inverter 4. This inverter 4 converts the current into alternating current of a desired frequency, passes through a matching transformer T, is electrically matched with a matching capacitor C, and is applied to the solenoid coil 2. As a result, the solenoid coil 2 is alternately connected. Magnetic flux is generated.

図２の被加熱物１００は、前処理設備１３から搬出されてソレノイド式コイル２に搬送され、このソレノイド式コイル２で誘導加熱された後、後処理設備１４へと搬送される。
図３は、本発明の他の実施形態としての誘導加熱装置の概略構成を示す斜視図である。
図３において、既述の図２との対応部には同一の参照符号を附してある。即ち、周波数変換装置６、整合装置５、および、ソレノイド式コイル２が導体７を介して順次接続される構造およびその機能などは図２と同様である。 The object to be heated 100 in FIG. 2 is unloaded from the pretreatment facility 13 and conveyed to the solenoid coil 2. After being induction-heated by the solenoid coil 2, the object to be heated 100 is conveyed to the posttreatment facility 14.
FIG. 3 is a perspective view showing a schematic configuration of an induction heating apparatus as another embodiment of the present invention.
In FIG. 3, the same reference numerals are assigned to the corresponding parts in FIG. That is, the structure in which the frequency conversion device 6, the matching device 5, and the solenoid coil 2 are sequentially connected via the conductor 7 and the function thereof are the same as those in FIG.

導体７の外部周辺部には導体７を被う第１の非磁性金属板８が設けられ、また、ソレノイド式コイル２の外部周辺部にはソレノイド式コイル２を被う非磁性金属板１５が設けられている。
図２を参照して既述のように、被加熱物１００はソレノイド式コイル２の中空部を通して搬送されるが、この被加熱物１００の搬送におけるソレノイド式コイル２への入口側と出口側には各々被加熱物１００を被う第２の非磁性金属板２５、および、２６が設けられている。 A first nonmagnetic metal plate 8 covering the conductor 7 is provided on the outer peripheral portion of the conductor 7, and a nonmagnetic metal plate 15 covering the solenoid coil 2 is provided on the outer peripheral portion of the solenoid type coil 2. Is provided.
As described above with reference to FIG. 2, the object to be heated 100 is conveyed through the hollow portion of the solenoid type coil 2, and on the inlet side and the outlet side to the solenoid type coil 2 in the conveyance of the object to be heated 100. Are provided with second nonmagnetic metal plates 25 and 26 each covering the object to be heated 100.

第２の非磁性金属板２５、および、２６の上記非加熱物１の搬送方向に略沿う長さＬは、その開口部の幅寸法Ｗまたは高さ寸法Ｈいずれか大きい方の寸法以上の長さとなるように構成されている。
なお、図３では開口部の幅寸法Ｗは開口部の高さ寸法Ｈ以上の寸法があり、上述の非加熱物１の搬送方向に略沿う長さＬがこの幅寸法Ｗ以上となるように構成されている場合を示している。 The length L of the second nonmagnetic metal plate 25 and 26 substantially along the conveying direction of the non-heated object 1 is longer than the larger one of the width dimension W or the height dimension H of the opening. It is comprised so that it may become.
In FIG. 3, the width dimension W of the opening has a dimension equal to or larger than the height dimension H of the opening, and the length L substantially along the conveying direction of the non-heated material 1 is equal to or larger than the width dimension W. The case where it is configured is shown.

上述の非磁性金属板８、１５、２５、２６は互いに電気的に接続されると共に、ソレノイド式コイル２、整合装置５、周波数変換装置６および導体７のそれぞれの金属筐体と電気的に接続されている。
なお、非磁性金属板８、１５、２５、２６を構成する材料としては、電気抵抗が小さく、かつ、加工性の良好な金属であればよいが、銅をベースとするものが特に望ましい。
上工程（図示せず）から搬送された被加熱物１００はソレノイド式コイル２に搬送され、ソレノイド式コイル２で誘導加熱された後、下工程（図示せず）へと搬送される。 The above-described nonmagnetic metal plates 8, 15, 25, and 26 are electrically connected to each other and electrically connected to the respective metal housings of the solenoid coil 2, the matching device 5, the frequency converter 6 and the conductor 7. Has been.
The material constituting the nonmagnetic metal plates 8, 15, 25, and 26 may be any metal that has low electrical resistance and good workability, but is preferably based on copper.
The object to be heated 100 transported from the upper process (not shown) is transported to the solenoid coil 2, and after being induction-heated by the solenoid coil 2, it is transported to the lower process (not shown).

ここで、互いに電気的に接続された非磁性金属板（図２：８、１１、１２、１５）または（図３：８、１５、２５、２６）で周波数変換装置６、整合装置５、ソレノイド式コイル２および導体７をそれぞれ被うことにより、誘起電流が大きい場合においても、非磁性金属板８、１５の電位差を低減しつつ、磁界の漏洩を防ぐことができる。
このため、ソレノイド式コイル２による鋼板の誘導加熱、特に周波数の高い鋼鈑の誘導加熱において、鋼板の幅方向の均熱性を確保できる。
更に、効率の高い薄鋼板の誘導加熱を実現することが可能になると共に、電波障害を抑制し、感電の無い安全な誘導加熱装置を提供することができる。 Here, the non-magnetic metal plates (FIG. 2: 8, 11, 12, 15) or (FIG. 3: 8, 15, 25, 26) electrically connected to each other, the frequency converter 6, the matching device 5, and the solenoid. By covering the expression coil 2 and the conductor 7 respectively, leakage of the magnetic field can be prevented while reducing the potential difference between the nonmagnetic metal plates 8 and 15 even when the induced current is large.
For this reason, in the induction heating of the steel plate by the solenoid coil 2, particularly the induction heating of the steel plate having a high frequency, it is possible to ensure the thermal uniformity in the width direction of the steel plate.
Furthermore, highly efficient induction heating of a thin steel plate can be realized, and a radio induction can be suppressed and a safe induction heating apparatus without electric shock can be provided.

図４は、本発明の図２、図３の装置における非磁性金属板８および１５の接続構造を示すＡ−Ａ線（図２、図３）で切断した断面図である。
図４において、ソレノイド式コイル２の筐体１７と導体７の筐体１８は、ボルト１６で接続されている。
上述のソレノイド式コイル２を被う非磁性金属板１５は、ソレノイド式コイル２の金属筐体１７にネジ１９で固定されている。
同様に、ソレノイド式コイル２と整合装置５を接続する導体７を被う非磁性金属板８は、導体７の金属筐体１８にねじ１９で固定されている。 4 is a cross-sectional view taken along line AA (FIGS. 2 and 3) showing a connection structure of the nonmagnetic metal plates 8 and 15 in the apparatus of FIGS. 2 and 3 of the present invention.
In FIG. 4, the casing 17 of the solenoid coil 2 and the casing 18 of the conductor 7 are connected by a bolt 16.
The nonmagnetic metal plate 15 covering the solenoid coil 2 is fixed to the metal casing 17 of the solenoid coil 2 with screws 19.
Similarly, the nonmagnetic metal plate 8 covering the conductor 7 connecting the solenoid coil 2 and the matching device 5 is fixed to the metal casing 18 of the conductor 7 with a screw 19.

なお、金属筐体１７、１８、非磁性金属板８、１５などには塗料などを塗らないようにして、互いに電気的な導通性を持たせることができる。また、金属筐体１７、１８は、金属製の山形鋼、みぞ形鋼などを溶接して製作することができる。
ここで、金属筐体１７、１８を金属製の山形鋼、みぞ形鋼などを溶接して製作すると、その溶接歪み・加工歪みや製造誤差などにより、ソレノイド式コイル２の筐体１７と導体７の筐体１８との間には隙間（図示せず）ができる。 It should be noted that the metal casings 17 and 18 and the nonmagnetic metal plates 8 and 15 can be made electrically conductive with each other without applying paint or the like. The metal casings 17 and 18 can be manufactured by welding metal angle steel, groove steel, or the like.
Here, when the metal casings 17 and 18 are manufactured by welding metal angle steel, groove steel, or the like, the casing 17 of the solenoid coil 2 and the conductor 7 are caused by welding distortion, processing distortion, manufacturing error, or the like. A gap (not shown) is formed between the housing 18 and the housing 18.

このため、ソレノイド式コイル２の筐体１７と導体７の筐体１８との間の接触抵抗が大きくなり、ソレノイド式コイル２の筐体１７と導体７の筐体１８の接続による非磁性金属板８、１５には、その内部の導体７に流れる高周波電流からの磁界によって誘導される渦電流が別個に生じ、非磁性金属板８、１５間および金属筐体１７、１８間においては、別個の電位を持つため電位差が生じる。 For this reason, the contact resistance between the casing 17 of the solenoid coil 2 and the casing 18 of the conductor 7 is increased, and the nonmagnetic metal plate is formed by connecting the casing 17 of the solenoid coil 2 and the casing 18 of the conductor 7. 8 and 15 separately generate eddy currents induced by a magnetic field from a high-frequency current flowing in the conductor 7 inside thereof, and are separately provided between the nonmagnetic metal plates 8 and 15 and between the metal casings 17 and 18. Since it has a potential, a potential difference occurs.

この電位差は、非磁性金属板８、１５に亘り人体が接触したときに、人体を流れる電流を生じさせる。さらに、人体の一端が非磁性金属板８、１５のいずれかに接触し、人体の他端が床面にあるときに、床面の電位は金属筐体１７、１８の中間にあるため、人体の接触している２点間には大きな電位差が発生し、人体に電流が流れる。
このため、ソレノイド式コイル２の筐体１７と導体７の筐体１８の間の隙間も非磁性金属板で被うことで、ソレノイド式コイル２の筐体１７と導体７の筐体１８の接続による非磁性金属板８、１５間の電位差を解消するようにしてもよい。 This potential difference generates a current flowing through the human body when the human body contacts the nonmagnetic metal plates 8 and 15. Furthermore, when one end of the human body is in contact with either of the non-magnetic metal plates 8 and 15 and the other end of the human body is on the floor surface, the potential of the floor surface is in the middle of the metal casings 17 and 18, so A large potential difference is generated between the two points in contact with each other, and a current flows through the human body.
Therefore, the gap between the casing 17 of the solenoid coil 2 and the casing 18 of the conductor 7 is also covered with a nonmagnetic metal plate, so that the casing 17 of the solenoid coil 2 and the casing 18 of the conductor 7 are connected. The potential difference between the nonmagnetic metal plates 8 and 15 may be eliminated.

図５は、本発明の図２、図３の装置における非磁性金属板の接続構造の他の例を示すＡ−Ａ線で切断した断面図である。
図５において、ソレノイド式コイル２を被う非磁性金属板１５と導体７を被う非磁性金属板８の境界は、平板形状の非磁性金属板２０で被われ、ネジ１９で接続されている。なお、平板形状の非磁性金属板２０の代わりに、Ｕ字形状の非磁性金属板２１を用いてもよい。
ここで、非磁性金属板８、１５、２０、２１には塗料などを塗らないようにして、互いに電気的な導通性を持たせることができる。 FIG. 5 is a cross-sectional view taken along line AA showing another example of a nonmagnetic metal plate connection structure in the apparatus of FIGS. 2 and 3 of the present invention.
In FIG. 5, the boundary between the nonmagnetic metal plate 15 covering the solenoid coil 2 and the nonmagnetic metal plate 8 covering the conductor 7 is covered with a flat nonmagnetic metal plate 20 and connected by screws 19. . A U-shaped nonmagnetic metal plate 21 may be used instead of the flat nonmagnetic metal plate 20.
Here, the nonmagnetic metal plates 8, 15, 20, and 21 can be made electrically conductive with each other without applying paint or the like.

これにより、ソレノイド式コイル２を被う非磁性金属板１５と導体７を被う非磁性金属板８をより確実に電気的に接続することができ、非磁性金属板８、１５には共通の誘導電流が流れるようにすることが可能となることから、その間の電位差を低減することができる。
床面の電位は浮遊容量により金属筐体１７、１８の中間にあるため、非磁性金属板８、１５の床面に対する電位を低減させることができる。
なお、導体７、整合装置５、周波数変換装置６それぞれの筐体、非磁性金属板の接続構造は図１あるいは図２を参照して既述のものと同様である。 As a result, the nonmagnetic metal plate 15 covering the solenoid coil 2 and the nonmagnetic metal plate 8 covering the conductor 7 can be more reliably electrically connected. Since the induced current can flow, the potential difference therebetween can be reduced.
Since the potential of the floor surface is in the middle of the metal casings 17 and 18 due to the stray capacitance, the potential of the nonmagnetic metal plates 8 and 15 with respect to the floor surface can be reduced.
The connection structure of the conductor 7, the matching device 5, the frequency converter 6, and the nonmagnetic metal plate is the same as that described above with reference to FIG. 1 or FIG. 2.

図６は、本発明の図２、図３の装置における非磁性金属板１２、１５の接続構造の更に他の例を示すＢ−Ｂ線で切断した断面図である。
図６において、ソレノイド式コイル２を被う非磁性金属板１５と後処理設備１４との境界は、平板形状の非磁性金属板１２で被われ、ネジ１９で接続されている。この構成において、被加熱物は図中矢線Ｙで示す方向に搬送される。
なお、ソレノイド式コイル２の使用条件は、高温物の近くで用いられるため高温に晒され続けること、前処理設備１３および後処理設備１４の熱的な膨張や歪みを受ける大型装置として構成されること、連続流れ生産ラインの中に配置されること等々、過酷なものであり、メンテナンスが定期的に行われることが欠かせない。 6 is a cross-sectional view taken along line BB showing still another example of the connection structure of the nonmagnetic metal plates 12 and 15 in the apparatus of FIGS. 2 and 3 of the present invention.
In FIG. 6, the boundary between the nonmagnetic metal plate 15 covering the solenoid coil 2 and the post-processing equipment 14 is covered with a flat nonmagnetic metal plate 12 and connected by screws 19. In this configuration, the object to be heated is conveyed in the direction indicated by the arrow Y in the figure.
The use conditions of the solenoid coil 2 are configured as large-scale devices that are exposed to high temperatures because they are used near high-temperature objects, and that are subject to thermal expansion and distortion of the pretreatment facility 13 and the posttreatment facility 14. And being placed in a continuous flow production line, etc., are harsh and require regular maintenance.

このような使用条件を考慮して、上述のような平板形状の非磁性金属板１２に替えて、その側断面が図示のようなＵ字形状の非磁性金属板２１、あるいは蛇腹状の非磁性金属板２４を用いてある程度の柔構造とし構造物間の隙間を最小化することができる。
以上の構成において、非磁性金属板１１、１２、１５、２１、２４には塗料などを塗らないようにして、互いに電気的な導通性を持たせることができる。 In consideration of such usage conditions, instead of the flat plate-like nonmagnetic metal plate 12 as described above, a U-shaped nonmagnetic metal plate 21 having a side cross section as shown in the figure or a bellows-like nonmagnetic metal plate. By using the metal plate 24, a flexible structure can be obtained to some extent, and the gap between the structures can be minimized.
In the above configuration, the nonmagnetic metal plates 11, 12, 15, 21, 24 can be electrically connected to each other without applying paint or the like.

これにより、ソレノイド式コイル２を被う非磁性金属板１５と後処理設備１４とを非磁性金属板１２（または２１または２４）により確実に電気的に接続することができ、非磁性金属板１５と後処理設備１４には共通の誘導電流が流れるようにすることが可能となり、両者間の電位差を低減することができる。
床面の電位は浮遊容量により金属筐体１７、１８の中間にあるため、非磁性金属板１５の床面に対する電位を低減させることができる。なお、前処理設備１３とソレノイド式コイル２を被う非磁性金属板１５とを接続する非磁性金属板１１の接続構造は図６と同様である。 Thereby, the nonmagnetic metal plate 15 covering the solenoid coil 2 and the post-processing equipment 14 can be reliably electrically connected by the nonmagnetic metal plate 12 (or 21 or 24). It is possible to allow a common induced current to flow through the post-processing equipment 14 and reduce the potential difference between the two.
Since the potential of the floor surface is in the middle of the metal casings 17 and 18 due to the stray capacitance, the potential with respect to the floor surface of the nonmagnetic metal plate 15 can be reduced. The connection structure of the nonmagnetic metal plate 11 that connects the pretreatment facility 13 and the nonmagnetic metal plate 15 covering the solenoid coil 2 is the same as that shown in FIG.

図７は、本発明の一実施形態に係る金属筐体５、６および非磁性金属板８、１５と非磁性金属帯２２との接続構造の一例を示す平面図である。
図７において、周波数変換装置６、整合装置５およびソレノイド式コイル２を順次接続する導体７（図７では内部に隠れて見えない）は非磁性金属板８で被われ、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの両側面に沿って非磁性金属帯２２が施工されている。 FIG. 7 is a plan view showing an example of a connection structure between the metal housings 5 and 6 and the nonmagnetic metal plates 8 and 15 and the nonmagnetic metal strip 22 according to the embodiment of the present invention.
In FIG. 7, a conductor 7 (not hidden in FIG. 7) that sequentially connects the frequency converter 6, the matching device 5, and the solenoid coil 2 is covered with a nonmagnetic metal plate 8. A nonmagnetic metal strip 22 is applied along both side surfaces of the device 5 and the frequency converter 6.

上述のソレノイド式コイル２、整合装置５および周波数変換装置６の筐体はそれぞれ４カ所で非磁性金属帯２３を介して非磁性金属帯２２に電気的に接続されている。
この非磁性金属帯２２は接地されると共に、その表面は絶縁物（図示せず）で電気的に絶縁されている。
なお、非磁性金属帯２２の幅は３０ｍｍ以上とすることが好ましく、例えば、非磁性金属帯２２は、幅５０ｍｍ、厚み０．３ｍｍの銅を用いて作製することができる。 The casings of the solenoid coil 2, the matching device 5, and the frequency conversion device 6 are electrically connected to the nonmagnetic metal strip 22 through the nonmagnetic metal strip 23 at four locations.
The non-magnetic metal band 22 is grounded and its surface is electrically insulated with an insulator (not shown).
The width of the nonmagnetic metal band 22 is preferably 30 mm or more. For example, the nonmagnetic metal band 22 can be manufactured using copper having a width of 50 mm and a thickness of 0.3 mm.

なお、本例では１台の誘導加熱装置の場合に限定されることなく、複数台の誘導加熱装置を配置した場合にも有効である。この場合には、複数台のソレノイド式コイル２間にある被加熱物１も同様に非磁性金属板で被われると共に、ソレノイド式コイル２を被う金属板１５と電気的に接続される。
ここで、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体の非磁性金属板を相互に広幅の非磁性金属帯２２により電気的に接続することにより、各金属筐体間の電位差を低減させ、これら各部位の電位の平均値を静電誘導により金属筐体が設置されている床面の電位に近づけることができる。 In addition, in this example, it is not limited to the case of one induction heating apparatus, but is effective when a plurality of induction heating apparatuses are arranged. In this case, the object to be heated 1 between the plurality of solenoid coils 2 is similarly covered with a nonmagnetic metal plate and electrically connected to the metal plate 15 covering the solenoid coil 2.
Here, the nonmagnetic metal plates of the respective metal casings of the solenoid coil 2, the matching device 5, and the frequency converter 6 are electrically connected to each other by the wide nonmagnetic metal strip 22. The potential difference between them can be reduced, and the average value of the potentials of these parts can be brought close to the potential of the floor surface on which the metal housing is installed by electrostatic induction.

電気回路的には、各金属筐体と床面間の浮遊容量により、金属筐体間の電位差を低下させることができる。高周波の電位であるため、この浮遊容量によるインピーダンスは大きな効果を有している。
さらに、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板をそれぞれ幅３０ｍｍ以上の非磁性金属帯２２に電気的に接続すると共に、接地線２４を介して接地することにより、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板間の接続インピーダンスを低減させることが可能となる。 In terms of electrical circuit, the potential difference between the metal casings can be reduced by the stray capacitance between the metal casings and the floor surface. Since this is a high-frequency potential, the impedance due to this stray capacitance has a great effect.
Further, the respective metal casings of the solenoid coil 2, the matching device 5 and the frequency converter 6 and the nonmagnetic metal plate covering them are electrically connected to the nonmagnetic metal strip 22 having a width of 30 mm or more, and grounded. By grounding via the wire 24, it is possible to reduce the connection impedance between the respective metal housings of the solenoid coil 2, the matching device 5, and the frequency converter 6 and the nonmagnetic metal plate covering them. .

さらにまた、大地に対する接地インピーダンスを減少させ、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板、金属筐体が設置されている床面の電位を共通的に大地電位に近づけることができ、それらの２箇所以上に人体が接触した場合においても、人体への接触電流を低減させることができる。
なお、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板を線状ではなく帯状の非磁性金属帯２２に接続して接地することが必要なのは、次の理由による。 Furthermore, the ground surface on which the ground impedance to the ground is reduced and the solenoid casing 2, the matching device 5, and the frequency converter 6, and the nonmagnetic metal plate and the metal casing covering them are installed. Can be brought close to the ground potential in common, and even when the human body comes into contact with two or more of them, the contact current to the human body can be reduced.
The metal casings of the solenoid coil 2, the matching device 5 and the frequency converter 6 and the nonmagnetic metal plate covering them may be connected to the strip-shaped nonmagnetic metal strip 22 and grounded. This is necessary for the following reasons.

すなわち、誘導加熱装置の周波数が高い場合には、表皮効果により、線の抵抗は表面積が大きいほど低減でき、線の断面積による低減効果は小さくなることと、高周波のために線のインダクタンスによるインピーダンスが無視できなくなり、その線の接地インピーダンスが高くなることから、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板の電位が対地の電位から高くなると共に、金属筐体が設置されている床面の電位も対地の電位と離れることによる。 That is, when the frequency of the induction heating device is high, the resistance of the wire can be reduced as the surface area increases due to the skin effect, and the reduction effect due to the cross-sectional area of the wire becomes smaller, and the impedance due to the inductance of the wire due to the high frequency. Since the ground impedance of the wire becomes high, the potential of the metal casing of the solenoid coil 2, the matching device 5, and the frequency converter 6 and the potential of the nonmagnetic metal plate covering them are ground potentials. And the potential of the floor on which the metal casing is installed is also separated from the ground potential.

一方、非磁性金属帯２２を帯状にすることにより、表面積の増大による抵抗の低減させることが可能となると共に、そのインダクタンスによるインピーダンスの低減をもたらし接地インピーダンスを低減し、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板および床面の電位を大地電位に共通的に近づけることができ、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体およびそれらを被う非磁性金属板筐体および床面の２箇所以上に人体が接触した場合においても、接触電流を小さくすることができる。 On the other hand, by forming the non-magnetic metal band 22 into a band shape, it becomes possible to reduce the resistance due to the increase in surface area, and also to reduce the impedance due to the inductance, thereby reducing the ground impedance, the solenoid coil 2, the matching device 5. The potential of each metal casing of the frequency converter 6 and the nonmagnetic metal plate and the floor covering them can be made close to the ground potential in common, the solenoid coil 2, the matching device 5, the frequency converter The contact current can be reduced even when the human body comes into contact with two or more locations of each of the metal casings 6 and the nonmagnetic metal plate casing and the floor surface covering them.

また、非磁性金属帯２２の帯の幅は平均して３０ｍｍ以上が必要である。３０ｍｍ未満であると、必要なインピーダンス低減効果を得ることが難しいからである。
また、この帯の厚みは、表皮効果による抵抗およびインダクタンスから見て表面積に依存するため、０．１ｍｍ程度あれば十分であるが、加工性等を考慮して決めることができる。
実際の設備では、レイアウト上の都合、あるいは、加工上の制約から全長にわたって３０ｍｍ幅を確保するのは難しい場合もあるが、３０ｍｍ幅の帯状体とした場合のインピーダンスと同等、もしくは、それ以下のインピーダンスであればよい。
なお、非磁性金属帯２２、２３を構成する材料としては、電気抵抗が小さく、かつ、加工性の良好な金属であればよいが、銅をベースとするものが特に望ましい。 Further, the width of the non-magnetic metal band 22 needs to be 30 mm or more on average. This is because if it is less than 30 mm, it is difficult to obtain a necessary impedance reduction effect.
Further, the thickness of the band depends on the surface area in view of resistance and inductance due to the skin effect, so about 0.1 mm is sufficient, but can be determined in consideration of workability and the like.
In actual equipment, it may be difficult to secure a 30 mm width over the entire length due to layout considerations or processing limitations, but it is equivalent to or less than the impedance of a 30 mm wide strip. Any impedance can be used.
In addition, as a material which comprises the nonmagnetic metal strips 22 and 23, what is necessary is just a metal with small electrical resistance and favorable workability, However, The thing based on copper is especially desirable.

また、誘導加熱装置の運転周波数は１００ｋＨｚから１ＭＨｚの範囲に設定することが好ましい。１００ｋＨｚ未満では、ソレノイド式コイル２、整合装置５、周波数変換装置６のそれぞれの金属筐体に発生する電位がそれほど大きくなく、電位そのものが問題ないからであり、また、１ＭＨｚ超では、誘導加熱装置のコイル電圧が高くなりすぎ、実用的でないからである。 The operating frequency of the induction heating device is preferably set in the range of 100 kHz to 1 MHz. If the frequency is less than 100 kHz, the potential generated in the respective metal casings of the solenoid coil 2, the matching device 5, and the frequency conversion device 6 is not so large, and the potential itself is not a problem. This is because the coil voltage becomes too high and is not practical.

また、誘導加熱装置の電力を１００ｋＷ以上に設定する場合に本発明の装置はその真価を発揮する。１００ｋW未満では、誘導加熱装置のコイル電流の値がそれほど大きくないため、整合装置５、周波数変換装置６のそれぞれの金属筐体に発生する電位がそれほど大きくならず、電位そのものが感電を引き起こすほど大きくならないからである。
表１、表２に本発明の実施例の接触電流と電界強度を従来例と比較して示す。 Moreover, when the electric power of the induction heating apparatus is set to 100 kW or more, the apparatus of the present invention exhibits its true value. If it is less than 100 kW, the value of the coil current of the induction heating device is not so large, so that the potential generated in each metal casing of the matching device 5 and the frequency converter 6 is not so large, and the potential itself is so large as to cause an electric shock. Because it will not be.
Tables 1 and 2 show the contact current and electric field strength of the examples of the present invention in comparison with the conventional example.

表１には、本発明の実施例の接触電流を従来例と比較して示す。なお、第１実施例では図２と図５の誘導加熱装置、第２実施例では図２、図５および図７の誘導加熱装置を用い、従来例では図１０の誘導加熱装置を用いた。また、箇所Ａ、Ｂは、本誘導加熱装置において接触電流が大きかった代表的な箇所２カ所の値である。
また、誘導加熱装置の周波数は４８０ｋＨｚ、電力は８００ｋＷ、被加熱材は、板厚が０．３ｍｍ、板幅が１２７０ｍｍ、材質が磁性鉄板であり、帯状の非磁性金属帯は板厚が０．３ｍｍ、板幅が５０ｍｍ、材質が銅であった。
いずれの実施例においても、安全基準値以下とすることができた。特に、帯状の非磁性金属帯を用いた第２実施例ではその効果は著しく、感電の無い安全な誘導加熱装置を実現することができた。 Table 1 shows the contact current of the embodiment of the present invention in comparison with the conventional example. In the first example, the induction heating apparatus shown in FIGS. 2 and 5 was used. In the second example, the induction heating apparatus shown in FIGS. 2, 5, and 7 was used. In the conventional example, the induction heating apparatus shown in FIG. 10 was used. Further, locations A and B are values at two representative locations where the contact current was large in the induction heating apparatus.
The frequency of the induction heating device is 480 kHz, the power is 800 kW, the material to be heated is 0.3 mm thick, the plate width is 1270 mm, the material is a magnetic iron plate, and the strip-like nonmagnetic metal strip has a thickness of 0. It was 3 mm, the plate width was 50 mm, and the material was copper.
In any of the examples, the safety standard value or less could be achieved. In particular, in the second embodiment using a strip-like nonmagnetic metal strip, the effect was remarkable, and a safe induction heating apparatus without electric shock could be realized.

表２には、本発明法の場合と従来法の場合の電界強度の例を比較して示す。本発明法とすることにより基準値以下とすることができる。 Table 2 shows a comparison of examples of the electric field strength in the case of the method of the present invention and the case of the conventional method. By adopting the method of the present invention, the reference value or less can be achieved.

また、鋼板に替え、アルミニウム、銅など非磁性の非鉄金属の薄板をソレノイドコイルで加熱する場合においても、（図２又は図３と図５）または（図２又は図３と図５および図７）の誘導加熱装置と同様の構造とすることにより、同様の効果を得ることができる。 Further, in the case where a thin plate made of non-magnetic non-ferrous metal such as aluminum or copper is heated with a solenoid coil in place of the steel plate (FIG. 2, FIG. 3, FIG. 5) or (FIG. 2, FIG. 3, FIG. 5, FIG. 7). ), The same effect can be obtained.

本発明の実施形態としての誘導加熱装置の概略構成を示す電気主回路単線結線図である。It is an electric main circuit single line connection figure which shows schematic structure of the induction heating apparatus as embodiment of this invention. 本発明の一実施形態としての誘導加熱装置の概略構成を示す斜視図である。It is a perspective view which shows schematic structure of the induction heating apparatus as one Embodiment of this invention. 本発明の他の実施形態としての誘導加熱装置の概略構成を示す斜視図である。It is a perspective view which shows schematic structure of the induction heating apparatus as other embodiment of this invention. 本発明の図２、図３の装置における非磁性金属板の接続構造の一例を示すＡ−Ａ線で切断した断面図である。It is sectional drawing cut | disconnected by the AA line which shows an example of the connection structure of the nonmagnetic metal plate in the apparatus of FIG. 2, FIG. 3 of this invention. 本発明の図２、図３の装置における非磁性金属板の接続構造の他の例を示すＡ−Ａ線で切断した断面図である。It is sectional drawing cut | disconnected by the AA line which shows the other example of the connection structure of the nonmagnetic metal plate in the apparatus of FIG. 2, FIG. 3 of this invention. 本発明の図２、図３の装置における非磁性金属板の接続構造の更に他の例を示すＢ−Ｂ線で切断した断面図である。It is sectional drawing cut | disconnected by the BB line which shows the further another example of the connection structure of the nonmagnetic metal plate in the apparatus of FIG. 2, FIG. 3 of this invention. 本発明の一実施形態に係る金属筐体および非磁性金属板と非磁性金属帯との接続構造の一例を示す平面図である。It is a top view which shows an example of the connection structure of the metal housing | casing which concerns on one Embodiment of this invention, a nonmagnetic metal plate, and a nonmagnetic metal strip. ソレノイド方式による誘導加熱方法を示す斜視図である。It is a perspective view which shows the induction heating method by a solenoid system. トランスバース方式による誘導加熱方法を示す斜視図である。It is a perspective view which shows the induction heating method by a transverse system. 従来の誘導加熱装置の概略構成を示す斜視図である。It is a perspective view which shows schematic structure of the conventional induction heating apparatus.

Explanation of symbols

１商用電源
２ソレノイド式コイル
３整流器
４インバータ
Ｔ整合用変圧器
Ｃ整合用コンデンサ
５整合装置
６周波数変換装置
７導体
８、１１、１２、１５、２０、２１、２４、２５、２６非磁性金属板
１３前処理設備
１４後処理設備
１６ボルト
１７、１８筐体
１９ネジ
２２、２３非磁性金属帯
１００被加熱物 DESCRIPTION OF SYMBOLS 1 Commercial power supply 2 Solenoid coil 3 Rectifier 4 Inverter T Matching transformer C Matching capacitor 5 Matching device 6 Frequency conversion device 7 Conductor 8, 11, 12, 15, 20, 21, 24, 25, 26 Nonmagnetic metal plate 13 Pre-processing equipment 14 Post-processing equipment 16 Bolts 17, 18 Housing 19 Screws 22, 23 Non-magnetic metal strip 100 Object to be heated

Claims

A coil for generating a magnetic flux for induction heating the object to be heated;
A frequency converter that converts the frequency of the voltage applied to the coil to a frequency suitable for induction heating;
A matching device that electrically matches the frequency converter and the coil;
A conductor for sequentially connecting the frequency converter, the matching device and the coil;
The frequency converter, the matching device, the coil, and the non-magnetic metal plate respectively disposed on the outer periphery of the conductor and covering the frequency converter, the matching device, the coil, and the conductor;
The metal housing of each of the frequency converter, the matching device, and the coil and the nonmagnetic metal plate are electrically connected to each other, and a grounded nonmagnetic metal strip having a width of 30 mm or more is provided. An induction heating device characterized by being electrically connected to a body and the non-magnetic metal plate.

A coil for generating a magnetic flux for induction heating the object to be heated;
A frequency converter that converts the frequency of the voltage applied to the coil to a frequency suitable for induction heating;
A matching device that electrically matches the frequency converter and the coil;
A conductor for sequentially connecting the frequency converter, the matching device and the coil;
A pretreatment facility installed on the upstream side of the coil in the carry-in direction of the heated object, having a metal casing and through which the heated object passes ;
A post-processing facility installed on the downstream side of the coil in the unloading direction of the object to be heated, having a metal casing and through which the object to be heated passes ;
A first nonmagnetic metal plate disposed at least on the outer periphery of the conductor and covering the conductor and electrically connected to each other;
A second non-conductive member disposed at a boundary between the coil and the pretreatment facility so as to cover an object to be heated carried into the coil and electrically connected to the first non-magnetic metal plate. A magnetic metal plate,
A third non-conductive member disposed at a boundary between the coil and the post-processing equipment so as to cover an object to be heated unloaded from the coil and electrically connected to the first non-magnetic metal plate. An induction heating device comprising a magnetic metal plate.

A coil for generating a magnetic flux for induction heating the object to be heated;
A frequency converter that converts the frequency of the voltage applied to the coil to a frequency suitable for induction heating;
A matching device that electrically matches the frequency converter and the coil;
A conductor for sequentially connecting the frequency converter, the matching device and the coil;
The frequency converter, the matching device, the coil, and the non-magnetic metal plate respectively disposed on the outer periphery of the conductor and covering the frequency converter, the matching device, the coil, and the conductor;
Pretreatment equipment installed on the upstream side of the coil in the carry-in direction of the heated object;
Post-processing equipment installed on the downstream side of the coil in the carry-out direction of the heated object;
A first nonmagnetic metal plate disposed at least on the outer periphery of the conductor and covering the conductor and electrically connected to each other;
The first non-magnetic metal plate and the metal housing of the pretreatment facility and the electric housing are arranged at a boundary portion between the coil and the pretreatment facility so as to cover an object to be heated carried into the coil. A second non-magnetic metal plate connected electrically,
The first non-magnetic metal plate and the metal housing of the post-processing equipment are electrically connected to the first processing unit and the post-processing equipment so as to cover an object to be heated unloaded from the coil. A third non-magnetic metal plate connected to each other,
The metal housing of each of the frequency converter, the matching device, and the coil and the nonmagnetic metal plate are electrically connected to each other, and a grounded nonmagnetic metal strip having a width of 30 mm or more is provided. An induction heating device characterized by being electrically connected to a body and the non-magnetic metal plate.

A coil for generating a magnetic flux for induction heating the object to be heated;
A frequency converter that converts the frequency of the voltage applied to the coil to a frequency suitable for induction heating;
A matching device that electrically matches the frequency converter and the coil;
A conductor for sequentially connecting the frequency converter, the matching device and the coil;
The frequency conversion device, the matching device, the coil, and the conductor are respectively disposed in the outer peripheral portion, and the frequency conversion device, the matching device, the coil, and the conductor are respectively covered and electrically connected to each other. A first non-magnetic metal plate;
It has an opening for allowing the object to be heated to be conveyed through the hollow portion of the coil, and the conveying direction over a length longer than the larger one of the width dimension or the height dimension of the opening. An induction heating apparatus comprising: a second magnetic metal plate that covers the object to be heated substantially along the line and is electrically connected to the first nonmagnetic metal plate.

A coil for generating a magnetic flux for induction heating the object to be heated;
A frequency converter that converts the frequency of the voltage applied to the coil to a frequency suitable for induction heating;
A matching device that electrically matches the frequency converter and the coil;
A conductor for sequentially connecting the frequency converter, the matching device and the coil;
The frequency converter, the matching device, the coil, and a first non-magnetic metal plate respectively disposed on the outer periphery of the conductor and covering the frequency converter, the matching device, the coil, and the conductor;
Electrically connecting each of the frequency conversion device, the matching device and the metal housing of the coil and the first non-magnetic metal plate,
It has an opening for allowing the object to be heated to be conveyed through the hollow portion of the coil, and the conveying direction over a length longer than the larger one of the width dimension or the height dimension of the opening. A second nonmagnetic metal plate that covers the object to be heated substantially along and is electrically connected to the first nonmagnetic metal plate,
An induction heating apparatus comprising: a nonmagnetic metal strip having a width of 30 mm or more that is electrically connected to the metal casing and the nonmagnetic metal plate and grounded.

The induction heating apparatus according to any one of claims 1 to 5, wherein an operating frequency is in a range of 100 kHz to 1 MHz and electric power is 100 kW or more.