JP4401432B1

JP4401432B1 - Insulator heater and in-furnace heater using the same

Info

Publication number: JP4401432B1
Application number: JP2009174451A
Authority: JP
Inventors: 五二川畑
Original assignee: ミクニ機工株式会社
Priority date: 2009-07-27
Filing date: 2009-07-27
Publication date: 2010-01-20
Anticipated expiration: 2029-07-27
Also published as: JP2011029029A

Abstract

【課題】炉内加熱ヒータの１本当たりの出力を向上させ、かつ加熱線の各二重線部における折返し先端部での短絡を良好に防止する。
【解決手段】炉内加熱ヒータ１は、折返し先端部１１ａおよび二重線部１１ｂを有する加熱線１１を複数セット備える。各加熱線１１の先端側には炉内加熱ヒータ用碍子１２が配置される。碍子１２は、各二重線部１１ｂを１本ずつ通す線挿通孔のセットＳを有するベース板部１２ａを備える。ベース板部１２ａは、基準線Ｌを含む垂直面に対して傾斜状に突出し、隣り合う折返し先端部１１ａ同士が短絡しないように線挿通孔のセットＳをセット毎に仕切る仕切り壁１２ｃと、それら仕切り壁１２ｃの突出端を円筒状に繋ぎ、折返し先端部１１ａのいずれもが保護管３１（保護カバー）の内周面と短絡しないように線挿通孔のセットＳの全てと保護管３１の内周面とを仕切る外周壁１２ｄとを一体に備える。
【選択図】図１０
An object of the present invention is to improve the output per one heater in a furnace and to prevent a short circuit at a folded tip in each double line portion of a heating wire.
An in-furnace heater 1 includes a plurality of heating wires 11 each having a folded tip portion 11a and a double wire portion 11b. An in-furnace heater heater 12 is disposed on the tip side of each heating wire 11. The insulator 12 includes a base plate portion 12a having a set S of line insertion holes through which each double line portion 11b passes. The base plate portion 12a protrudes in an inclined manner with respect to the vertical plane including the reference line L, and the partition wall 12c that partitions the set S of line insertion holes for each set so that adjacent folded tip portions 11a are not short-circuited, and these The protruding end of the partition wall 12c is connected in a cylindrical shape, and all of the set S of line insertion holes and the inside of the protective tube 31 are arranged so that none of the folded back end portions 11a is short-circuited with the inner peripheral surface of the protective tube 31 (protective cover). An outer peripheral wall 12d that partitions the peripheral surface is integrally provided.
[Selection] Figure 10

Description

本発明は、炉内加熱ヒータ用碍子およびそれを用いた炉内加熱ヒータに関し、特に加熱線の先端側に配置される碍子、およびその碍子を用いた炉内加熱ヒータに関する。 The present invention relates to an insulator for an in-furnace heater and an in-furnace heater using the same, and more particularly to an insulator disposed on the leading end side of a heating wire and an in-furnace heater using the insulator.

この種の炉内加熱ヒータ用碍子として、例えば下記特許文献１に記載されているように、加熱線を螺旋状に巻いて形成した発熱コイル内に配置されるものが知られている。この特許文献１では、碍子の基部に板状の第１短絡防止体が複数設けられ、各第１短絡防止体の先端に板状の第２短絡防止体が設けられている。そして、碍子が発熱コイルのピッチ間を回転しつつ移動できるように、各第１短絡防止体の取り付け位置や形状が設定されている。 As this kind of insulator for an in-furnace heater, for example, as described in Japanese Patent Application Laid-Open No. H10-228707, one disposed in a heating coil formed by winding a heating wire in a spiral shape is known. In Patent Document 1, a plurality of plate-like first short-circuit prevention bodies are provided at the base of the insulator, and a plate-like second short-circuit prevention body is provided at the tip of each first short-circuit prevention body. And the attachment position and shape of each 1st short circuit prevention body are set so that an insulator can move, rotating between the pitches of a heating coil.

特開平１０−１６２９４３号公報Japanese Patent Laid-Open No. 10-162943

上記特許文献１に記載されたような加熱線が螺旋状に巻かれた形態以外にも、加熱線が基端から先端に向かって延び、先端側で折り返されて再び基端側に戻る形態とされ、そのような折返し形態からなる二重線部が複数セット設けられるものがある。通常、後者の形態の加熱線によると、前者の形態の加熱線に比べて有効発熱部の長さを長く設定できるので、より大きな出力（発熱量）を得ることが可能である。この場合、後者の形態の加熱線においては、各セットの二重線部同士、および隣り合う各二重線部のセット同士の短絡を防止するために、碍子が加熱線の基端から先端にかけて二重線部の各加熱線を単独で通過させるように複数配置されることが多い。 In addition to the form in which the heating wire is spirally wound as described in Patent Document 1, the heating wire extends from the proximal end toward the distal end, is folded at the distal end side, and returns to the proximal end side again. In some cases, a plurality of sets of double line portions having such a folded shape are provided. Usually, according to the heating wire of the latter form, since the length of the effective heat generating part can be set longer than that of the heating wire of the former form, it is possible to obtain a larger output (heat generation amount). In this case, in the heating wire of the latter form, the insulator extends from the base end to the tip end of the heating wire in order to prevent a short circuit between the double wire portions of each set and between the sets of adjacent double wire portions. In many cases, a plurality of heating wires in the double wire portion are arranged so as to pass through alone.

ところが、例えば図１９に示すように、碍子１３０が複数配置される後者の形態では、加熱線１１０が通電による発熱で線膨張し、各二重線部１１０ｂにおける折返し先端部１１０ａ（ループ部分）が広がるように熱変形することがある。このため、隣り合う折返し先端部１１０ａ同士が接触することで、加熱線１１０が短絡し、断線してしまうという問題があった。 However, as shown in FIG. 19, for example, in the latter form in which a plurality of insulators 130 are arranged, the heating wire 110 linearly expands due to heat generated by energization, and the folded tip portion 110a (loop portion) in each double wire portion 110b. It may be thermally deformed to spread. For this reason, there existed a problem that the heating wire 110 will be short-circuited and disconnected, when adjacent folding front-end | tip parts 110a contact.

特に、近年では、炉内加熱ヒータ（以下、単にヒータともいう）は消耗部品なので、設備コストの削減の観点から、ヒータの使用本数を減らしたいとの要請がある一方、その使用本数を減らした場合でも、ヒータ全体の出力は維持あるいは向上させたいとの要請もある。このような両要請を実現するためには、ヒータ１本当たりの出力を大きく設定する必要があり、加熱線を出来るだけ密に（有効発熱部の長さをより長く）配置する必要がある。しかしながら、加熱線を密に配置すればするほど、隣り合う折返し先端部同士が接触しやすくなるので、上記した問題が発生するおそれが高くなる。 In particular, in recent years, the heater in the furnace (hereinafter also simply referred to as a heater) is a consumable part, so from the viewpoint of reducing equipment costs, there is a demand for a reduction in the number of heaters used, but the number of heaters used has been reduced. Even in such cases, there is a demand for maintaining or improving the output of the entire heater. In order to realize both of these requirements, it is necessary to set a large output per heater, and it is necessary to arrange the heating lines as densely as possible (the length of the effective heat generating portion is longer). However, the closer the heating wires are arranged, the easier the adjacent folded tip portions come into contact with each other.

本発明は、上記課題を解決するためになされたものであり、その目的は、上記した後者の形態の加熱線を用いて、ヒータ１本当たりの出力を向上させつつ、しかも加熱線の各二重線部における折返し先端部での短絡を良好に防止し得る炉内加熱ヒータ用碍子およびその碍子を用いた炉内加熱ヒータを提供することにある。 The present invention has been made in order to solve the above-described problems. The object of the present invention is to improve the output per heater by using the heating wire of the latter form described above, and to further improve the output of each heating wire. An object of the present invention is to provide an in-furnace heater heater that can satisfactorily prevent a short circuit at a folded tip in a heavy wire portion and an in-furnace heater using the insulator.

課題を解決するための手段および発明の効果Means for Solving the Problems and Effects of the Invention

上記課題を解決するために本発明は、基端から先端に向かって延び、先端側で折り返されて再び基端側に戻る加熱線の折返し形態からなる二重線部が複数セットあり、各セットの二重線部同士、および隣り合う各二重線部のセット同士の短絡を防止するために、加熱線の基端から先端にかけて二重線部の各加熱線を単独で通過させるように複数配置される炉内加熱ヒータ用碍子であって、それら複数の炉内加熱ヒータ用碍子のうち、先端部に配置される碍子は、各セットの二重線部を１本ずつ通す線挿通孔のセットを、基準線の周りに所定の角度間隔で有するベース板部を備えており、線挿通孔のセットは、基準線の周りの第１ピッチ円に沿って前記角度間隔で形成される第１線挿通孔と、第１ピッチ円に比べて小径の第２ピッチ円に沿って第１線挿通孔間の部位に対応するように前記角度間隔で形成される第２線挿通孔とで構成されており、ベース板部の、加熱線の各二重線部における折返し先端部側には、基準線を含む垂直面に対して傾斜状に突出し、隣り合う折返し先端部同士が短絡しないように線挿通孔のセットをセット毎に仕切る仕切り壁が一体に形成されていることを特徴とする。この場合、例えば仕切り壁の突出端を筒状に繋ぎ、折返し先端部のいずれもが該ベース板部の外周上を基準線から離れる向きに超えないように仕切る外周壁が一体に形成されていると好適である。 In order to solve the above-described problems, the present invention has a plurality of sets of double line portions each having a heating wire folded back shape that extends from the proximal end toward the distal end, is folded back at the distal end side, and returns to the proximal end side. In order to prevent short-circuiting between the double wire portions of each other and between sets of adjacent double wire portions, a plurality of heating wires of the double wire portions are individually passed from the proximal end to the distal end of the heating wire. Among the plurality of in-furnace heater heaters, the insulator disposed at the tip of the plurality of in-furnace heater heaters has a wire insertion hole through which one double line portion of each set passes. A base plate portion having a set at a predetermined angular interval around the reference line is provided, and the set of line insertion holes is a first pitch formed at the angular interval along a first pitch circle around the reference line. Along the line insertion hole and the second pitch circle having a smaller diameter than the first pitch circle It is comprised with the 2nd line penetration hole formed at the said angular interval so that it may correspond to the part between 1 line penetration holes, and it is on the return tip part side in each double line part of a heating line of a base board part. Is characterized in that a partition wall that protrudes in an inclined manner with respect to a vertical plane including the reference line and that partitions the set of line insertion holes for each set is formed integrally so that adjacent folded tip portions do not short-circuit each other. To do. In this case, for example, the projecting end of the partition wall is connected in a cylindrical shape, and the outer peripheral wall that partitions so that none of the folded tip ends exceed the outer periphery of the base plate portion in the direction away from the reference line is integrally formed. It is preferable.

この炉内加熱ヒータ用碍子では、第１ピッチ円に沿って形成される第１線挿通孔と、第２ピッチ円に沿って形成される第２線挿通孔とにより線挿通孔のセットが構成されており、第２線挿通孔が第１線挿通孔間の部位に対応する位置に配置されている。すなわち、第１線挿通孔と第２線挿通孔を円周方向に沿って見た場合、両挿通孔は千鳥状に配置されるようになっている。このため、線挿通孔が１つのピッチ円に沿って等角度間隔で形成され、隣り合う一対の線挿通孔が線挿通孔の１セットを構成する従来の炉内加熱ヒータ用碍子に比べて、線挿通孔のセット数を増やすことができ、それに応じて加熱線の使用本数を増やすことができるので、ヒータの出力を向上させることができる。この場合、複数のセットの二重線部の任意の１セットが、仕切り壁の隣り合うもの同士の間に位置し、その仕切り壁の近傍で折り返されるようになる。つまり、ベース板部の「行き方向」の線挿通孔から先端側に出た線部分は、隣り合う仕切り壁の近傍で折り返され、ベース板部の「帰り方向」の線挿通孔を通過して基端側へ戻る。これらの仕切り壁によって、複数セットの二重線部同士がベース板部の線挿通孔より先端側に延び出た部分で接触すること（短絡）が防止される。つまり、通電による発熱で各二重線部の折返し先端部のループが広がるように熱変形しても、仕切り壁があるから、それに当たってそれ以上、隣の二重線部側へ寄ることが阻止され、短絡が防止される。 In this insulator for an in-furnace heater, a set of line insertion holes is constituted by a first line insertion hole formed along the first pitch circle and a second line insertion hole formed along the second pitch circle. The second line insertion hole is disposed at a position corresponding to a portion between the first line insertion holes. That is, when the first line insertion hole and the second line insertion hole are viewed along the circumferential direction, both insertion holes are arranged in a staggered manner. For this reason, line insertion holes are formed at equal angular intervals along one pitch circle, and a pair of adjacent line insertion holes constitutes one set of line insertion holes, compared to a conventional furnace heater insulator, Since the number of sets of wire insertion holes can be increased and the number of heating wires used can be increased accordingly, the output of the heater can be improved. In this case, an arbitrary set of the plurality of sets of double line portions is positioned between adjacent ones of the partition walls and is folded in the vicinity of the partition walls. That is, the line portion that protrudes from the line insertion hole in the “bound direction” of the base plate portion toward the tip side is folded back in the vicinity of the adjacent partition wall and passes through the line insertion hole in the “return direction” of the base plate portion. Return to the base side. By these partition walls, a plurality of sets of double line portions are prevented from coming into contact (short circuit) at a portion extending from the line insertion hole of the base plate portion toward the tip side. In other words, even when heat is deformed by heat generated by energization so that the loop at the folded end of each double line part spreads out, there is a partition wall, so that it is prevented from approaching the adjacent double line part side. Short circuit is prevented.

また、上記課題を解決するために本発明は、基端から先端に向かって延び、先端側で折り返されて再び基端側に戻る加熱線の折返し形態からなる二重線部が複数セットあり、各セットの二重線部同士、および隣り合う各二重線部のセット同士の短絡を防止するために、加熱線の基端から先端にかけて二重線部の各加熱線を単独で通過させるように複数配置される炉内加熱ヒータ用碍子を備え、それら炉内加熱ヒータ用碍子の隣り合うもの同士が相互に連結可能とされ、連結状態にあるそれら複数の炉内加熱ヒータ用碍子が装着された碍子付き加熱線のアッセンブリの外側に、筒状の金属製の保護カバーが装着されてなる炉内加熱ヒータであって、それら複数の炉内加熱ヒータ用碍子のうち、先端部に配置される碍子は、各セットの二重線部を１本ずつ通す線挿通孔のセットを、基準線の周りに所定の角度間隔で有するベース板部を備えており、線挿通孔のセットは、基準線の周りの第１ピッチ円に沿って前記角度間隔で形成される第１線挿通孔と、第１ピッチ円に比べて小径の第２ピッチ円に沿って第１線挿通孔間の部位に対応するように前記角度間隔で形成される第２線挿通孔とで構成されており、ベース板部の、加熱線の各二重線部における折返し先端部側には、基準線を含む垂直面に対して傾斜状に突出し、隣り合う折返し先端部同士が短絡しないように線挿通孔のセットをセット毎に仕切る仕切り壁が一体に形成されていることを特徴とする。 Further, in order to solve the above-mentioned problems, the present invention has a plurality of sets of double line portions extending from the proximal end toward the distal end, folded back at the distal end side, and returned to the proximal end side to form the heating wire. In order to prevent a short circuit between the double line parts of each set and between the sets of adjacent double line parts, each heating line of the double line part is allowed to pass independently from the base end to the tip end of the heating line. A plurality of in-furnace heater heater insulators, adjacent ones of the in-furnace heater heaters can be connected to each other, and the plurality of in-furnace heater heaters in a connected state are mounted. A furnace heater in which a cylindrical metal protective cover is attached to the outside of the assembly of the heating wire with the insulator, and is disposed at the tip of the plurality of insulators for the furnace heater. Choshi is the double line part of each set A base plate portion having a set of line insertion holes for passing one by one around the reference line at a predetermined angular interval is provided, and the set of line insertion holes corresponds to the angle along the first pitch circle around the reference line. The first line insertion holes formed at intervals and the second line formed at the angular intervals so as to correspond to the portions between the first line insertion holes along the second pitch circle having a smaller diameter than the first pitch circle. It is composed of a line insertion hole, and on the side of the folding plate at each double line portion of the heating plate of the base plate portion, it protrudes in an inclined manner with respect to the vertical plane including the reference line, and the adjacent folding tip portion The partition wall which partitions the set of line insertion hole for every set so that they may not short-circuit is formed integrally.

この炉内加熱ヒータでは、線挿通孔のセットをセット毎に仕切る仕切り壁が基準線を含む垂直面に対して傾斜状に突出している。このため、通電による発熱で各二重線の折返し先端部が中心の基準線から離れる向きに反り返るように熱変形しても、傾斜状の仕切り壁が存在するため、反り返るように熱変形する折返し先端部が、この傾斜状の仕切り壁に当たりやすくなって、保護カバーの内周面に接触すること（短絡）が防止される。 In this in-furnace heater, a partition wall that partitions a set of line insertion holes for each set protrudes in an inclined manner with respect to a vertical plane including a reference line. For this reason, even if heat is generated so that the folded tip of each double wire is bent back in the direction away from the central reference line due to heat generated by energization, there is an inclined partition wall. It is easy for the tip portion to come into contact with the inclined partition wall, and contact with the inner peripheral surface of the protective cover (short circuit) is prevented.

この場合、例えば仕切り壁の突出端を筒状に繋ぎ、折返し先端部のいずれもが保護カバーの内周面と短絡しないように線挿通孔のセットの全てと該保護カバーの内周面とを仕切る外周壁が一体に形成されていると好適である。 In this case, for example, the protruding ends of the partition walls are connected in a cylindrical shape, and the entire set of line insertion holes and the inner peripheral surface of the protective cover are connected so that none of the folded tip ends are short-circuited with the inner peripheral surface of the protective cover. It is preferable that the outer peripheral wall to partition is formed integrally.

上記した傾斜状の仕切り壁の存在により、各二重線の折返し先端部が中心の基準線から離れる向きに反り返るように熱変形しても、保護カバーの内周面に接触することが防止されるが、熱変形の態様によっては折返し先端部が仕切り壁の間のスペースに向かって延び出す場合がある。このような場合でも、筒状の外周壁の存在により、折返し先端部がこの筒状の外周壁に当たることで、保護カバーの内周面に接触することがほぼ確実に防止される。 Due to the presence of the above-described inclined partition wall, it is possible to prevent contact between the inner peripheral surface of the protective cover even if the folded tip of each double line is thermally deformed so as to bend away from the center reference line. However, depending on the form of thermal deformation, the folded tip may extend toward the space between the partition walls. Even in such a case, due to the presence of the cylindrical outer peripheral wall, it is possible to almost certainly prevent the folded tip from contacting the inner peripheral surface of the protective cover by hitting the cylindrical outer peripheral wall.

本発明に係る炉内加熱ヒータ用碍子およびそれを用いた炉内加熱ヒータを適用した加熱炉を概略的に示す説明図。BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows schematically the heating furnace which applied the insulator for furnace heaters which concerns on this invention, and the furnace heater using the same. 図１に示した炉内加熱ヒータの主要部を構成するヒータ本体（碍子付き加熱線）のアッセンブリの斜視図。The perspective view of the assembly of the heater main body (heater with a lever) which comprises the principal part of the in-furnace heater shown in FIG. 図２に示した加熱線の斜視図。FIG. 3 is a perspective view of the heating wire shown in FIG. 2. 図２に示した碍子１２，１３の連結状態を示す斜視図。The perspective view which shows the connection state of the insulators 12 and 13 shown in FIG. 図２の部分拡大図。The elements on larger scale of FIG. 図２に示した加熱線とヒータ端子とを接続する前の、加熱線同士の結線状態を示す正面図。The front view which shows the connection state of heating wires before connecting the heating wire and heater terminal shown in FIG. （ａ）は図２に示したヒータ端子の斜視図。（ｂ）は碍子１６，１７等が介装された（ａ）のヒータ端子と図９の加熱線とを接続した状態を示す斜視図。(A) is a perspective view of the heater terminal shown in FIG. FIG. 10B is a perspective view showing a state where the heater terminal of FIG. 9A in which the insulators 16 and 17 are interposed and the heating wire of FIG. 9 are connected. 図２に示したヒータ本体の外側に装着される保護管の斜視図。The perspective view of the protective tube with which the outer side of the heater main body shown in FIG. 2 is mounted | worn. 図２に示したヒータ本体と図１１に示した保護管とを組み付けた状態を示す平面断面図（保護管のみ破断）。FIG. 12 is a plan sectional view showing a state in which the heater main body shown in FIG. 2 and the protective tube shown in FIG. 11 are assembled (only the protective tube is broken). （ａ）は碍子１２の平面図。（ｂ）は（ａ）の縦断面図。（ｃ）は（ａ）の底面図。（ｄ）は（ａ）のＡ−Ａ断面図。(A) is a top view of the insulator 12. FIG. (B) is a longitudinal sectional view of (a). (C) is a bottom view of (a). (D) is AA sectional drawing of (a). （ａ）は碍子１３の平面図。（ｂ）は（ａ）の縦断面図。（ｃ）は（ａ）の底面図。(A) is a top view of the insulator 13. FIG. (B) is a longitudinal sectional view of (a). (C) is a bottom view of (a). （ａ）は碍子１４の平面図。（ｂ）は（ａ）の縦断面図。（ｃ）は（ａ）のＢ−Ｂ断面図。(A) is a top view of the insulator 14. FIG. (B) is a longitudinal sectional view of (a). (C) is BB sectional drawing of (a). （ａ）は碍子１５の平面図。（ｂ）は（ａ）の縦断面図。(A) is a top view of the insulator 15. FIG. (B) is a longitudinal sectional view of (a). （ａ）は碍子１６の平面図。（ｂ）は（ａ）の縦断面図。(A) is a top view of the insulator 16. FIG. (B) is a longitudinal sectional view of (a). （ａ）は碍子１７の平面図。（ｂ）は（ａ）の縦断面図。(A) is a top view of the insulator 17. FIG. (B) is a longitudinal sectional view of (a). 加熱線の折返し先端部が発熱により線膨張した状態を示す説明図。Explanatory drawing which shows the state by which the folding | turning front-end | tip part of the heating wire was linearly expanded by heat_generation | fever. （ａ）は本発明の実施例２に係る碍子１２’の平面図。（ｂ）は（ａ）の縦断面図。(A) is a top view of insulator 12 'concerning Example 2 of the present invention. (B) is a longitudinal sectional view of (a). 本発明の変形例に係る碍子１２’’の縦断面図。The longitudinal cross-sectional view of insulator 12 '' concerning the modification of this invention. 従来の碍子を用いた場合において、加熱線の発熱による線膨張に起因して折返し先端部が断線した状態を示す説明図。Explanatory drawing which shows the state where the folding | turning front-end | tip part was disconnected due to the linear expansion by the heat_generation | fever of a heating wire in the case of using the conventional insulator.

以下、本発明の実施の形態について図面を用いて説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１（ａ），１（ｂ）は、本発明に係る炉内加熱ヒータ用碍子（以下、単に碍子という）１２、およびその碍子１２を用いた炉内加熱ヒータ１（加熱源）を適用した工業用熱処理設備としての加熱炉Ｆ１，Ｆ２を例示したものである。炉内加熱ヒータ１は、炉内の熱分布および熱処理効果の観点から、加熱炉Ｆ１のように垂直方向に複数設置される場合や、加熱炉Ｆ２のように水平方向に複数設置される場合がある。なお、本発明に係る碍子１２および炉内加熱ヒータ１は、炉内への扉が一つである加熱炉に限らず、入口用と出口用の各扉が設けられている加熱炉（例えば、連続炉）に広く適用することができる。 1 (a) and 1 (b), an in-furnace heater insulator (hereinafter simply referred to as an insulator) 12 according to the present invention and an in-furnace heater 1 (heat source) using the insulator 12 are applied. The furnaces F1 and F2 are illustrated as industrial heat treatment equipment. From the viewpoint of the heat distribution in the furnace and the heat treatment effect, a plurality of in-furnace heaters 1 may be installed in the vertical direction as in the heating furnace F1, or in a plurality in the horizontal direction as in the heating furnace F2. is there. The insulator 12 and the in-furnace heater 1 according to the present invention are not limited to a heating furnace having one door into the furnace, but a heating furnace provided with doors for entrance and exit (for example, It can be widely applied to continuous furnaces).

炉内加熱ヒータ１（図９参照）の主要部を構成するヒータ本体（碍子付き加熱線）のアッセンブリ１０は、図２および図３に示すように、加熱線（ヒータ素線）１１、碍子１２〜１７、およびヒータ端子２１を備えている。 As shown in FIGS. 2 and 3, an assembly 10 of a heater body (heating wire with an insulator) that constitutes a main part of the in-furnace heater 1 (see FIG. 9) includes a heating wire (heater wire) 11 and an insulator 12. To 17 and the heater terminal 21.

加熱線１１は、線状の金属製の電熱素材（例えば、ニクロム製の電熱素材）を基端から先端に向かって直線状に延び出させ、先端側でＵ字状に折り返して再び基端側に直線状に戻すような折返し形態を１セットとするものであり、折返し先端部１１ａと二重線部１１ｂとを有している。このような形態の加熱線１１が複数セット使用されて、全体で一つの発熱体を構成している。 The heating wire 11 is formed by linearly extending a linear metal electrothermal material (for example, nichrome electrothermal material) from the proximal end toward the distal end, folding back into a U shape at the distal end side, and again at the proximal end side. A set of folding forms that return to a straight line is a set, and has a folded tip portion 11a and a double wire portion 11b. A plurality of sets of heating wires 11 having such a form are used to constitute one heating element as a whole.

この実施例１では、例えば８セットの加熱線１１が使用されており、そのうち６セットの加熱線１１Ａは基端から先端までの全長（有効発熱部）がほぼ同じ長さに設定されている。残り２セットの加熱線１１Ｂは、いずれも２本ある基端部の一方が他方に比べて所定長だけ長く設定されており、この長く設定された部位がヒータ端子２１（図７参照）と溶接により接続されるリード部１１ｃ（溶接しろ）として機能するようになっている。 In the first embodiment, for example, eight sets of heating wires 11 are used, and six sets of heating wires 11A are set to have substantially the same total length (effective heat generating portion) from the base end to the tip end. In the remaining two sets of heating wires 11B, one of the two base end portions is set longer than the other by a predetermined length, and this long set portion is welded to the heater terminal 21 (see FIG. 7). It functions as a lead portion 11c (welding margin) connected by the above.

碍子１２〜１５は、図２に示すように、加熱線１１の先端側から基端側（ヒータ端子２１側）に向かってこの順に装着されている。また、碍子１６，１７は、ヒータ端子２１の基端側（加熱線１１側）から先端側に向かってこの順に装着されている。最初に、碍子１３〜１７について説明する。 As shown in FIG. 2, the insulators 12 to 15 are mounted in this order from the distal end side of the heating wire 11 toward the proximal end side (heater terminal 21 side). The insulators 16 and 17 are attached in this order from the proximal end side (heating wire 11 side) of the heater terminal 21 toward the distal end side. First, the insulators 13 to 17 will be described.

碍子１３は、図１１に示すように、各セットの加熱線１１における二重線部１１ｂを１本ずつ通す線挿通孔のセットを、基準線（中心軸線）Ｌの周りの所定の角度間隔で有する略円板状（径方向外方に向かうに従って上面が低くなるように傾斜する形態）のベース板部１３ａを備えている。この実施例では、８セットの加熱線１１に対応して、線挿通孔のセットが８セット設けられている。 As shown in FIG. 11, the insulator 13 is a set of wire insertion holes through the double wire portions 11 b of the heating wires 11 of each set one by one at a predetermined angular interval around the reference line (center axis line) L. And a base plate portion 13a having a substantially disk shape (inclined so that the upper surface becomes lower toward the outside in the radial direction). In this embodiment, eight sets of wire insertion holes are provided corresponding to eight sets of heating wires 11.

線挿通孔のセットは、基準線Ｌの周りの第１ピッチ円Ｐ１に沿って角度θ（＝４５度）の等角度間隔で形成される第１線挿通孔１３ａ１と、第１ピッチ円Ｐ１に比べて小径の第２ピッチ円Ｐ２に沿って第１線挿通孔１３ａ１間の部位に対応するように角度θ（＝４５度）の等角度間隔で形成される第２線挿通孔１３ａ２とで構成されている。具体的には、第１線挿通孔１３ａ１と第２線挿通孔１３ａ２は、ベース板部１３ａを円周方向に沿って見た場合、千鳥状に配置されるようになっている。 The set of line insertion holes is formed on the first pitch circle P1 and the first line insertion holes 13a1 formed at equal angular intervals of the angle θ (= 45 degrees) along the first pitch circle P1 around the reference line L. Compared with the second pitch circle P2 having a smaller diameter, the second line insertion holes 13a2 are formed at equiangular intervals of an angle θ (= 45 degrees) so as to correspond to portions between the first line insertion holes 13a1. Has been. Specifically, the first line insertion holes 13a1 and the second line insertion holes 13a2 are arranged in a staggered manner when the base plate portion 13a is viewed along the circumferential direction.

ベース板部１３ａには、各加熱線１１の折返し先端部１１ａ側に突出する連結基部１３ｂが設けられている。連結基部１３ｂは、基準線Ｌを中心軸線とする略円柱状（先端側が基端側に比べて若干量だけ先細りとなる形態）をなし、ベース板部１３ａの各線挿通孔１３ａ２よりも径方向内側部位に一体形成されている。 The base plate portion 13 a is provided with a connecting base portion 13 b that protrudes toward the folded tip portion 11 a of each heating wire 11. The connecting base portion 13b has a substantially columnar shape with the reference line L as the central axis (a shape in which the distal end side is tapered by a slight amount compared to the proximal end side), and is radially inward of each line insertion hole 13a2 of the base plate portion 13a. It is formed integrally with the part.

連結基部１３ｂには、基準線Ｌを中心軸線とする円形かつ段付き状の挿通孔１３ｂ１が形成されている。挿通孔１３ｂ１は、補強のための芯棒や、温度検出のためのセンサを組み入れる等して適宜利用される。ベース板部１３ａには、挿通孔１３ｂ１に連通する正四角錐台状の凹部１３ａ３が形成されている。連結基部１３ｂの先端には、ベース板部１３ａの凹部１３ａ３における底辺および高さ寸法を若干量だけ小さくした正四角錐台状の凸部１３ｂ２が形成されている。 The connection base portion 13b is formed with a circular and stepped insertion hole 13b1 having the reference line L as the central axis. The insertion hole 13b1 is appropriately used by incorporating a core rod for reinforcement and a sensor for temperature detection. The base plate portion 13a is formed with a regular quadrangular frustum-shaped recess 13a3 communicating with the insertion hole 13b1. At the tip of the connecting base portion 13b, a regular quadrangular pyramid-shaped convex portion 13b2 is formed in which the bottom and height dimensions of the concave portion 13a3 of the base plate portion 13a are slightly reduced.

このように構成された碍子１３は、図４に示すように、複数用いられ、任意の碍子１３の凸部１３ｂ２が他の碍子１３の凹部１３ａ３に嵌合することで、複数の碍子１３が基準線Ｌの方向に数珠繋ぎ状に連結される。この場合、凸部１３ｂ２および凹部１３ａ３が正四角錐台状に形成されているので、各碍子１３が連結された状態では、碍子１３同士の基準線Ｌ回りの相対回転が防止されるようになっている。 As shown in FIG. 4, a plurality of the insulators 13 configured as described above are used, and the protrusions 13 b 2 of any insulator 13 are fitted into the recesses 13 a 3 of the other insulators 13, so that the plurality of insulators 13 can be used as a reference. In the direction of the line L, they are connected in a daisy chain. In this case, since the convex portion 13b2 and the concave portion 13a3 are formed in a regular quadrangular pyramid shape, relative rotation around the reference line L between the insulators 13 is prevented when the insulators 13 are connected. Yes.

各碍子１３の線挿通孔１３ａ１には、図５に示すように、各加熱線１１の二重線部１１ｂが１本ずつ通り、各二重線部１１ｂの基端部は、図２および図７（ｂ）に示すように、最も基端側に近い位置に配置される碍子１３のベース板部１３ａから突出した状態となる。この状態で、一方の加熱線１１Ｂのリード部１１ｃと他方の加熱線１１Ｂのリード部１１ｃとが、図６にて矢印で示すように、全加熱線１１の二重線部１１ｂを経由して直列に繋がるよう、所定の加熱線１１Ａ同士、所定の加熱線１１Ａと加熱線１１Ｂとが、円柱状の結線部材１９ａで接続され、あるいは板状の結線部材１９ｂで接続されている。 As shown in FIG. 5, one double wire portion 11b of each heating wire 11 passes through the wire insertion hole 13a1 of each insulator 13, and the base end portion of each double wire portion 11b is shown in FIGS. As shown in FIG. 7B, the base plate portion 13a of the insulator 13 that is disposed at a position closest to the base end side is projected. In this state, the lead portion 11c of one heating wire 11B and the lead portion 11c of the other heating wire 11B are routed through the double wire portion 11b of all the heating wires 11 as shown by arrows in FIG. The predetermined heating wires 11A, the predetermined heating wires 11A and the heating wires 11B are connected by a columnar connecting member 19a or by a plate-like connecting member 19b so as to be connected in series.

碍子１４は、図２および図１２に示すように、円板状をなし、ベース基板部１３ａの線挿通孔１３ａ１，１３ａ２にそれぞれ対応する線挿通孔１４ａ１，１４ａ２と、基準線Ｌを中心軸線とする円形の貫通孔１４ｂとを有している。碍子１４は、各加熱線１１Ｂのリード部１１ｃのみを挿通させ（図７（ｂ）参照）、線挿通孔１４ａ１，１４ａ２の形成されていない板面にて結線部材１９ａ，１９ｂの端面と当接することにより、碍子１３側への配置位置が規定されるようになっている。 As shown in FIGS. 2 and 12, the insulator 14 has a disk shape, line insertion holes 14a1 and 14a2 corresponding to the line insertion holes 13a1 and 13a2 of the base substrate portion 13a, and the reference line L as the central axis. And a circular through hole 14b. The insulator 14 is inserted through only the lead portion 11c of each heating wire 11B (see FIG. 7B), and comes into contact with the end surfaces of the connecting members 19a and 19b on the plate surface where the wire insertion holes 14a1 and 14a2 are not formed. Thus, the arrangement position on the insulator 13 side is defined.

碍子１５は、図２および図１３に示すように、碍子１４とほぼ同じ大きさの円板状をなし、各加熱線１１Ｂのリード部１１ｃのみを挿通させる線挿通孔１５ａを有していて、碍子１４の板面に当接した状態で配置される。 As shown in FIGS. 2 and 13, the insulator 15 has a disk shape that is substantially the same size as the insulator 14, and has a line insertion hole 15 a for inserting only the lead portion 11 c of each heating wire 11 </ b> B, It arrange | positions in the state contact | abutted to the board surface of the insulator 14. FIG.

碍子１６は、図２および図１４に示すように、碍子１５とほぼ同じ大きさの円板状をなし、各ヒータ端子２１のみを挿通させる線挿通孔１６ａを有していて（図７（ｂ）参照）、各加熱線１１Ｂのリード部１１ｃにおける基端面に当接した状態で配置される。 As shown in FIGS. 2 and 14, the insulator 16 has a disk shape that is substantially the same size as the insulator 15, and has line insertion holes 16 a through which only the heater terminals 21 are inserted (FIG. 7B. )), And arranged in contact with the base end face of the lead portion 11c of each heating wire 11B.

碍子１７は、図２および図１５に示すように、碍子１５に比べて直径、厚さともに大きな小径部１７ａと大径部１７ｂを有する二段の円柱状をなし、各ヒータ端子２１のみを挿通させる線挿通孔１７ｃを有している。 As shown in FIGS. 2 and 15, the insulator 17 has a two-stage cylindrical shape having a small diameter portion 17 a and a large diameter portion 17 b that are larger in diameter and thickness than the insulator 15, and only the heater terminals 21 are inserted. A line insertion hole 17c is provided.

ヒータ端子２１は、図７（ａ）に示すように、直線棒状の非発熱体であり、その一端にて電源（例えば、交流電源）側の端子と結線するための端子板部２１ａを備えている。ヒータ端子２１には、図７（ｂ）に示すように、端子板部２１ａ側から加熱線１１Ｂのリード部１１ｃ側に向けて碍子１７、断熱部材１８（例えば、複数の丸状ブランケット）、碍子１６がこの順に挿通され、基端部が碍子１５の板面に当接した状態で加熱線１１Ｂのリード部１１ｃに溶接により接続される。 As shown in FIG. 7A, the heater terminal 21 is a straight bar-like non-heating element, and includes a terminal plate portion 21a for connecting to a power source (for example, AC power source) side terminal at one end thereof. Yes. As shown in FIG. 7B, the heater terminal 21 includes an insulator 17, a heat insulating member 18 (for example, a plurality of round blankets), an insulator from the terminal plate portion 21a side toward the lead portion 11c side of the heating wire 11B. 16 are inserted in this order, and connected to the lead portion 11c of the heating wire 11B by welding in a state where the base end portion is in contact with the plate surface of the insulator 15.

上記の碍子１２〜１７、断熱部材１８およびヒータ端子２１が装着されたヒータ本体のアッセンブリ１０（図２参照）の外側には、図８に示すような、保護カバーとしての円筒状の金属製（例えば、ステンレス製）の保護管（ラジアントチューブ）３１が装着される。保護管３１は、先端部にて底部３１ａを備え、基端部にて加熱炉Ｆ１，Ｆ２のフランジ部（図１参照）に固定するためのフランジ部３１ｂを備えている。 On the outside of the heater body assembly 10 (see FIG. 2) to which the insulators 12 to 17, the heat insulating member 18 and the heater terminal 21 are attached, a cylindrical metal as a protective cover as shown in FIG. For example, a protection tube (radiant tube) 31 made of stainless steel is attached. The protective tube 31 includes a bottom portion 31a at the distal end portion and a flange portion 31b for fixing to the flange portions (see FIG. 1) of the heating furnaces F1 and F2 at the proximal end portion.

この実施例１では、例えば図９に示すように、上記碍子１６を流用して、保護管３１側の碍子として保護管３１の底部３１ａに着座させた状態で、ヒータ本体のアッセンブリ１０を保護管３１内に組み込み、碍子１２をその碍子１６に接触させることにより、そのアッセンブリ１０の保護管３１内での先端位置を規定するようにしている。 In the first embodiment, for example, as shown in FIG. 9, the heater body assembly 10 is placed in the protective tube while the insulator 16 is diverted and is seated on the bottom 31 a of the protective tube 31 as an insulator on the protective tube 31 side. 31, and the insulator 12 is brought into contact with the insulator 16, whereby the tip position of the assembly 10 in the protective tube 31 is defined.

ヒータ本体のアッセンブリ１０が保護管３１内に組み込まれた状態では、碍子１２〜１６の外側面と保護管３１の内周面との間に所定長の隙間が形成され、また、碍子１７の小径部１７ａにおける外側面と保護管３１の内周面との間に極僅かの隙間が形成されるとともに、大径部１７ｂが保護管３１のフランジ部３１ｂに着座するようになっている。 In the state where the heater body assembly 10 is incorporated in the protective tube 31, a predetermined length of gap is formed between the outer surface of the insulators 12 to 16 and the inner peripheral surface of the protective tube 31, and the small diameter of the insulator 17 A very small gap is formed between the outer surface of the portion 17 a and the inner peripheral surface of the protective tube 31, and the large-diameter portion 17 b is seated on the flange portion 31 b of the protective tube 31.

そして、上記のように構成された炉内加熱ヒータ１では、電源（図示省略）からヒータ端子２１への通電により、加熱線１１が発熱し、発生した熱が保護管３１を経て外部へ放射されることとなる。 In the in-furnace heater 1 configured as described above, the heating wire 11 generates heat by energizing the heater terminal 21 from a power source (not shown), and the generated heat is radiated to the outside through the protective tube 31. The Rukoto.

ところで、この実施例１では、加熱線１１の先端側に配置される碍子１２が、図２および図１０に示すように、碍子１３に共通する形状と、共通しない形状との両形状を具備するように構成されている。具体的には、図１０に示すように、各セットの加熱線１１における二重線部１１ｂを１本ずつ通す線挿通孔のセットＳを、基準線Ｌの周りの所定の角度間隔で有する略円板状のベース板部１２ａを備え、かつ各加熱線１１の折返し先端部１１ａ側に突出する連結基部１２ｂを備える点において共通している。 By the way, in this Example 1, the insulator 12 arrange | positioned at the front end side of the heating wire 11 has both the shape which is common to the insulator 13, and the shape which is not common, as shown in FIG.2 and FIG.10. It is configured as follows. Specifically, as shown in FIG. 10, the set S of line insertion holes through which one double line portion 11b of the heating wire 11 of each set passes one by one at a predetermined angular interval around the reference line L. This is common in that it includes a disk-shaped base plate portion 12 a and a connecting base portion 12 b that protrudes toward the folded tip portion 11 a of each heating wire 11.

具体的には、線挿通孔のセットＳは、基準線Ｌの周りの第１ピッチ円Ｐ１に沿って角度θ（＝４５度）の等角度間隔で形成される第１線挿通孔１２ａ１と、第１ピッチ円Ｐ１に比べて小径の第２ピッチ円Ｐ２に沿って第１線挿通孔１２ａ１間の部位に対応するように角度θ（＝４５度）の等角度間隔で形成される第２線挿通孔１２ａ２とで構成されている。第１線挿通孔１２ａ１と第２線挿通孔１２ａ２は、ベース板部１２ａを円周方向に沿って見た場合、千鳥状に配置されている。 Specifically, the set S of line insertion holes includes first line insertion holes 12a1 formed at equal angular intervals of an angle θ (= 45 degrees) along the first pitch circle P1 around the reference line L; Second lines formed at equiangular intervals of an angle θ (= 45 degrees) so as to correspond to portions between the first line insertion holes 12a1 along the second pitch circle P2 having a smaller diameter than the first pitch circle P1. It is comprised with the insertion hole 12a2. The first line insertion holes 12a1 and the second line insertion holes 12a2 are arranged in a staggered manner when the base plate portion 12a is viewed along the circumferential direction.

また、連結基部１２ｂは、碍子１３の連結基部１３ｂと同様、基準線Ｌを中心軸線とする略円柱状をなし、ベース板部１２ａの各線挿通孔１２ａ２よりも径方向内側部位に一体形成されている。連結基部１２ｂには、基準線Ｌを中心軸線とする円形かつ段付き状の挿通孔１２ｂ１が形成されており、ベース板部１２ａには、挿通孔１２ｂ１に連通する正四角錐台状の凹部１２ａ３が形成されている。凹部１２ａ３は、碍子１３に形成された凹部１３ａ３とほぼ同じ大きさに形成されており、基端側に配置される碍子１３の凸部１３ｂ２と嵌まり合って連結状態となる。 Similarly to the connecting base portion 13b of the insulator 13, the connecting base portion 12b has a substantially cylindrical shape with the reference line L as the central axis, and is integrally formed at a radially inner portion than the respective line insertion holes 12a2 of the base plate portion 12a. Yes. The connection base 12b is formed with a circular and stepped insertion hole 12b1 with the reference line L as the central axis, and the base plate 12a has a regular quadrangular frustum-shaped recess 12a3 communicating with the insertion hole 12b1. Is formed. The concave portion 12a3 is formed to be approximately the same size as the concave portion 13a3 formed in the insulator 13, and fits with the convex portion 13b2 of the insulator 13 arranged on the proximal end side to be connected.

これに対して、ベース板部１２ａの各加熱線１１の折返し先端部１１ａ側には、仕切り壁１２ｃと外周壁１２ｄとが一体に形成されている点において、このような仕切り壁等のない碍子１３と異なっている。また、碍子１２の連結基部１２ｂには、連結のための凸部が省略されている点において、連結基部１３ｂに凸部１３ｂ２が形成されている碍子１３と異なっている。 On the other hand, an insulator without such a partition wall or the like in that a partition wall 12c and an outer peripheral wall 12d are integrally formed on the folded tip end portion 11a side of each heating wire 11 of the base plate portion 12a. 13 and different. Further, the connecting base portion 12b of the insulator 12 is different from the insulator 13 in which the protruding portion 13b2 is formed on the connecting base portion 13b in that a protruding portion for connection is omitted.

仕切り壁１２ｃは、図１０（ｂ）の図示下端にてベース板部１２ａに、内側端にて連結基部１２ｂに接続され、基準線Ｌを含む垂直面に対して傾斜状に突出し、加熱線１１の隣り合う折返し先端部１１ａ同士が短絡しないように線挿通孔のセットＳをセット毎に仕切っている。ここで、垂直面は、仕切り壁１２ｃ毎に規定されるものであり、任意の仕切り壁１２ｃに対応する垂直面としては、例えばその仕切り壁１２ｃの内側端と基準線Ｌを通るものを選ぶことができる。つまり、仕切り壁１２ｃは、仕切り壁１２ｃ毎に同じ基準で規定された垂直面に対してそれぞれ傾斜している。 The partition wall 12c is connected to the base plate portion 12a at the lower end of FIG. 10B and to the connecting base portion 12b at the inner end, protrudes in an inclined manner with respect to the vertical plane including the reference line L, and the heating wire 11 The set S of line insertion holes is partitioned for each set so that the adjacent folded tip portions 11a are not short-circuited. Here, the vertical plane is defined for each partition wall 12c. For example, a vertical plane corresponding to an arbitrary partition wall 12c is selected to pass through the inner end of the partition wall 12c and the reference line L. Can do. That is, the partition wall 12c is inclined with respect to the vertical plane defined by the same reference for each partition wall 12c.

外周壁１２ｄは、仕切り壁１２ｃの突出端を円筒状に繋ぎ、加熱線１１の折返し先端部１１ａのいずれもがベース板部１２ａの外周上を基準線Ｌから離れる向きに超えないように仕切っている。つまり、外周壁１２ｄは、加熱線１１の折返し先端部１１ａのいずれもが保護管３１の内周面と短絡しないようにベース板部１２ａの線挿通孔のセットＳの全てと保護管３１の内周面とを仕切っている。 The outer peripheral wall 12d connects the protruding ends of the partition wall 12c in a cylindrical shape, and partitions so that none of the folded tip end portions 11a of the heating wire 11 exceed the outer periphery of the base plate portion 12a in a direction away from the reference line L. Yes. That is, the outer peripheral wall 12d is formed so that all of the folded tip portions 11a of the heating wire 11 do not short-circuit with the inner peripheral surface of the protective tube 31 and all of the set S of the line insertion holes of the base plate portion 12a and the protective tube 31. Partitions from the surrounding surface.

仕切り壁１２ｃと外周壁１２ｄは、ベース板部１２ａの板面からの高さ寸法が同じ長さに設定されている。この高さ寸法は、加熱線１１の発熱時に折返し先端部１１ａが基準線Ｌの方向に向かって最大に線膨張した場合でも超えることのない長さ、すなわち加熱線１１の線径が例えば５〜１０ｍｍであり、加熱線１１の有効発熱部の長さが例えば１０００〜１５００ｍｍであって、ベース板部１２ａの直径が９０〜１００ｍｍであるとき、例えば１５〜３０ｍｍ程度となるように設定されている。 The partition wall 12c and the outer peripheral wall 12d are set to have the same height from the plate surface of the base plate portion 12a. This height dimension is a length that does not exceed even when the folded tip portion 11a linearly expands in the direction of the reference line L when the heating wire 11 generates heat, that is, the wire diameter of the heating wire 11 is, for example, 5 to 5. When the length of the effective heat generating portion of the heating wire 11 is 1000 to 1500 mm and the diameter of the base plate portion 12a is 90 to 100 mm, for example, it is set to be about 15 to 30 mm. .

上記のように構成された碍子１２〜１４を用いることにより、線挿通孔が１つのピッチ円に沿って等角度間隔で形成され、隣り合う一対の線挿通孔が線挿通孔の１セットを構成する従来の碍子に比べて、線挿通孔のセットＳ数を増やすことができ、それに応じて加熱線１１の使用本数を増やすことができるので、炉内加熱ヒータ１の出力を向上させることができる。 By using the insulators 12 to 14 configured as described above, the line insertion holes are formed at equal angular intervals along one pitch circle, and a pair of adjacent line insertion holes constitute one set of line insertion holes. Compared to the conventional insulator, the number S of wire insertion holes can be increased, and the number of heating wires 11 used can be increased accordingly, so that the output of the in-furnace heater 1 can be improved. .

そして、碍子１２を加熱線１１の先端側に配置すると、図１６にて破線で示すように、複数のセットの二重線部１１ｂの任意の１セットが、仕切り壁１２ｃの隣り合うもの同士の間に位置し、その仕切り壁１２ｃの近傍で折り返されるようになる。つまり、碍子１２のベース板部１２ａにおける「行き方向」の線挿通孔１２ａ１（１２ａ２）から先端側に出た線部分は、隣り合う仕切り壁１２ｃの近傍で折り返され、ベース板部１２ａの「帰り方向」の線挿通孔１２ａ２（１２ａ１）を通過して基端側へ戻る。 Then, when the insulator 12 is disposed on the leading end side of the heating wire 11, as shown by a broken line in FIG. 16, an arbitrary set of a plurality of sets of double wire portions 11b is formed between adjacent ones of the partition walls 12c. It is located in between and is folded back in the vicinity of the partition wall 12c. That is, the line portion that protrudes from the line insertion hole 12a1 (12a2) in the “going direction” in the base plate portion 12a of the insulator 12 to the front end side is folded back in the vicinity of the adjacent partition wall 12c, and the “return” of the base plate portion 12a. Direction "through the line insertion hole 12a2 (12a1) and return to the base end side.

これらの仕切り壁１２ｃによって、複数セットの二重線部１１ｂ同士がベース板部１２ａの線挿通孔１２ａ１，１２ａ２より先端側に延び出た部分で接触すること（短絡）が防止される。つまり、通電による発熱で各加熱線１１の二重線部１１ｂが異なる態様で線膨張し、あるいは折返し先端部１１ａのループが広がるように熱変形しようとしても、仕切り壁１２ｃがあるから、それに当たってそれ以上、隣の折返し先端部１１ａ側へ寄ることが阻止され、最終的には、図１６にて二点鎖線で示すように、折返し先端部１１ａが基準線Ｌの方向に延び出すようになって、折返し先端部１１ａ同士の短絡が防止される。 These partition walls 12c prevent a plurality of sets of double line portions 11b from coming into contact (short circuit) at portions extending from the line insertion holes 12a1 and 12a2 of the base plate portion 12a toward the distal end side. That is, even if the double wire portion 11b of each heating wire 11 linearly expands in a different manner due to heat generated by energization, or when it is thermally deformed so that the loop of the folded tip portion 11a expands, there is a partition wall 12c. Further, it is prevented from approaching the adjacent folded tip 11a side, and finally the folded tip 11a extends in the direction of the reference line L as shown by a two-dot chain line in FIG. Thus, a short circuit between the folded tip portions 11a is prevented.

また、上記のように構成された炉内加熱ヒータ１を用いると、通電による発熱で各加熱線１１の二重線部１１ｂにおける折返し先端部１１ａが基準線Ｌから離れる向きに反り返るように熱変形しようとしても、外周壁１２ｄがあるから、それに当たってそれ以上、保護管３１の内周面側へ寄ることが阻止され、最終的には、図１６にて二点鎖線で示すように、折返し先端部１１ａが基準線Ｌの方向に延び出すようになって、保護管３１の内周面に接触すること（短絡）が防止される。 Further, when the in-furnace heater 1 configured as described above is used, thermal deformation is performed so that the folded tip portion 11a of the double wire portion 11b of each heating wire 11 is warped in a direction away from the reference line L due to heat generated by energization. Even if it is going to be done, since there is the outer peripheral wall 12d, it is prevented from further approaching the inner peripheral surface side of the protective tube 31, and finally, as shown by a two-dot chain line in FIG. The part 11a extends in the direction of the reference line L, and contact (short circuit) with the inner peripheral surface of the protective tube 31 is prevented.

上記実施例１においては、ベース板部１２ａに、仕切り壁１２ｃの突出端を円筒状に繋ぎ、線挿通孔のセットＳの全てと保護管３１の内周面とを仕切る外周壁１２ｄを一体に形成したので、加熱線１１の折返し先端部１１ａが仕切り壁１２ｃの間のスペースに向かって延び出しても、円筒状の外周壁１２ｄの存在により、折返し先端部１１ａがこの円筒状の外周壁１２ｄに当たることで、保護管３１の内周面に接触することをほぼ確実に防止できた。ただし、例えば図１７の碍子１２’に示すように、外周壁１２ｄを省略してもよい。 In the first embodiment, the outer peripheral wall 12d that connects the protruding end of the partition wall 12c in a cylindrical shape to the base plate portion 12a and partitions the entire set S of line insertion holes and the inner peripheral surface of the protective tube 31 is integrated. Even if the folded front end portion 11a of the heating wire 11 extends toward the space between the partition walls 12c, the folded front end portion 11a becomes the cylindrical outer peripheral wall 12d due to the presence of the cylindrical outer peripheral wall 12d. The contact with the inner peripheral surface of the protective tube 31 could be almost certainly prevented by hitting. However, the outer peripheral wall 12d may be omitted as shown by an insulator 12 'in FIG.

この実施例２のように外周壁１２ｄを省略するようにしても、仕切り壁１２ｃが基準線Ｌを含む垂直面に対して傾斜状に突出配置されているので、反り返るように熱変形する折返し先端部１１ａが、この傾斜状の仕切り壁１２ｃに当たって、保護管３１の内周面への接触には至らないことが十分に期待される。なお、図１７に示した碍子１２’において、外周壁１２ｄが省略されている点を除けば、その他の構成は碍子１２と同じであるため、碍子１２と同じ機能を果たす部位には同一の符号を付して説明は省略する。 Even if the outer peripheral wall 12d is omitted as in the second embodiment, since the partition wall 12c is disposed so as to be inclined with respect to the vertical plane including the reference line L, the folded tip that is thermally deformed to warp. It is sufficiently expected that the portion 11a hits the inclined partition wall 12c and does not reach the inner peripheral surface of the protective tube 31. In addition, in the insulator 12 ′ shown in FIG. 17, except for the point that the outer peripheral wall 12d is omitted, the other configurations are the same as those of the insulator 12. Therefore, the parts having the same functions as those of the insulator 12 have the same reference numerals. The description is omitted.

（変形例）
碍子１２，１２’は、その先端側において他の碍子１３等と連結されることがなく、単に保護管３１側の碍子１６等と接触できる形状であればよいので、上記実施例１，２では、連結基端部１２ｂの先端に凸部を設けないように構成したが、碍子１３を成形するための型を利用して、碍子１２を成形することも可能である。したがって、この場合には、例えば図１８に示すように、碍子１２’’の連結基端部１２ｂの先端に碍子１３とほぼ同じ形状の凸部１２ｂ２が形成されるようになるが、このような碍子１２’’を用いて炉内加熱ヒータを構成してもよい。なお、図１８において、凸部１２ｂ２以外の構成は碍子１２と同じである。 (Modification)
Since the insulators 12 and 12 ′ are not connected to the insulator 13 or the like on the distal end side, and may simply be in contact with the insulator 16 or the like on the protective tube 31 side, Although the projecting portion is not provided at the distal end of the coupling base end portion 12b, the insulator 12 can be formed using a mold for forming the insulator 13. Accordingly, in this case, for example, as shown in FIG. 18, a convex portion 12b2 having substantially the same shape as the insulator 13 is formed at the distal end of the connecting base end portion 12b of the insulator 12 ''. An in-furnace heater may be configured using the insulator 12 ''. In FIG. 18, the configuration other than the convex portion 12b2 is the same as that of the insulator 12.

上記実施例等においては、碍子１２等と碍子１３、または碍子１３同士が四角錐台状の凹部１２ａ３と凸部１３ｂ２との嵌合により、または凹部１３ａ３と凸部１３ｂ２との嵌合により、基準線Ｌ回りの相互の相対回転が防止される構成とした。ただし、凹部、凸部は四角錐台状に限らず、例えば半月状であってもよい。 In the above-described embodiments, the insulator 12 or the like and the insulator 13 or the insulators 13 are connected to each other by fitting the concave pyramid-shaped concave portion 12a3 and the convex portion 13b2 or by fitting the concave portion 13a3 and the convex portion 13b2. The relative rotation around the line L is prevented. However, the concave and convex portions are not limited to a quadrangular pyramid shape, and may be, for example, a half moon shape.

また、碍子１２等における線挿通孔のセット数は、ベース板部１２ａの大きさや加熱線１１の線径等に応じて適宜変更可能である。 Moreover, the number of sets of the wire insertion holes in the insulator 12 or the like can be appropriately changed according to the size of the base plate portion 12a, the wire diameter of the heating wire 11, or the like.

さらに、碍子１２等のベース板部１２ａは、円板形状に限らず、例えば正多角形状に形成してもよい。また、これに対応して保護管３１を、例えば正多角形の筒状に形成してもよい。 Furthermore, the base plate portion 12a such as the insulator 12 is not limited to the disc shape, and may be formed in, for example, a regular polygon shape. Correspondingly, the protective tube 31 may be formed in a regular polygonal cylinder, for example.

Ｆ１，Ｆ２加熱炉
１炉内加熱ヒータ
１０ヒータ本体（碍子付き加熱線）のアッセンブリ
１１，１１Ａ，１１Ｂ加熱線
１１ａ折返し先端部
１１ｂ二重線部
１１ｃリード部
１２〜１７碍子
１２ａベース板部
Ｓ線挿通孔のセット
１２ａ１第１線挿通孔
１２ａ２第２線挿通孔
１２ａ３凹部
１２ｂ連結基部
１２ｂ１挿通孔
１２ｃ仕切り壁
１２ｄ外周壁
２１ヒータ端子
３１保護管
１２’，１２’’ 碍子 F1, F2 Heating furnace 1 In-furnace heater 10 Heater body (heating wire with insulator) assembly 11, 11A, 11B Heating wire 11a Folding tip 11b Double wire portion 11c Lead portion 12-17 Insulator 12a Base plate portion S wire Insertion hole set 12a1 First wire insertion hole 12a2 Second wire insertion hole 12a3 Recess 12b Connection base 12b1 Insertion hole 12c Partition wall 12d Outer wall 21 Heater terminal 31 Protective tube 12 ', 12''insulator

Claims

基端から先端に向かって延び、先端側で折り返されて再び基端側に戻る加熱線の折返し形態からなる二重線部が複数セットあり、各セットの二重線部同士、および隣り合う各二重線部のセット同士の短絡を防止するために、前記加熱線の基端から先端にかけて前記二重線部の各加熱線を単独で通過させるように複数配置される炉内加熱ヒータ用碍子であって、
それら複数の炉内加熱ヒータ用碍子のうち、先端部に配置される碍子は、前記各セットの二重線部を１本ずつ通す線挿通孔のセットを、基準線の周りに所定の角度間隔で有するベース板部を備えており、
前記線挿通孔のセットは、前記基準線の周りの第１ピッチ円に沿って前記角度間隔で形成される第１線挿通孔と、前記第１ピッチ円に比べて小径の第２ピッチ円に沿って前記第１線挿通孔間の部位に対応するように前記角度間隔で形成される第２線挿通孔とで構成されており、
前記ベース板部の、前記加熱線の各二重線部における折返し先端部側には、前記基準線を含む垂直面に対して傾斜状に突出し、隣り合う折返し先端部同士が短絡しないように前記線挿通孔のセットをセット毎に仕切る仕切り壁が一体に形成されていることを特徴とする炉内加熱ヒータ用碍子。 There are a plurality of sets of double line portions that are formed from a heating wire folded back that extends from the base end toward the front end, is folded back at the front end side, and returns to the base end side again. In order to prevent short-circuiting between sets of double wire portions, a plurality of insulators for in-furnace heaters are arranged so as to pass each heating wire of the double wire portion independently from the base end to the tip of the heating wire Because
Among the plurality of in-furnace heater heaters, the insulator disposed at the tip portion is a set of line insertion holes that pass through the double line portions of each set one by one at a predetermined angular interval around the reference line. With a base plate part
The set of the line insertion holes includes a first line insertion hole formed at the angular interval along a first pitch circle around the reference line, and a second pitch circle having a smaller diameter than the first pitch circle. A second line insertion hole formed at the angular interval so as to correspond to a portion between the first line insertion holes,
The base plate portion protrudes in an inclined manner with respect to the vertical plane including the reference line on the folded tip portion side in each double line portion of the heating wire, so that adjacent folded tip portions are not short-circuited. An insulator for an in-furnace heater, wherein a partition wall for partitioning a set of wire insertion holes for each set is integrally formed.

前記仕切り壁の突出端を筒状に繋ぎ、前記折返し先端部のいずれもが該ベース板部の外周上を前記基準線から離れる向きに超えないように仕切る外周壁が一体に形成されている請求項１に記載の炉内加熱ヒータ用碍子。 An outer peripheral wall that connects the projecting ends of the partition wall in a cylindrical shape and partitions so that none of the folded tip ends exceed the outer periphery of the base plate in a direction away from the reference line is integrally formed. Item 8. An insulator for an in-furnace heater according to Item 1.

基端から先端に向かって延び、先端側で折り返されて再び基端側に戻る加熱線の折返し形態からなる二重線部が複数セットあり、各セットの二重線部同士、および隣り合う各二重線部のセット同士の短絡を防止するために、前記加熱線の基端から先端にかけて前記二重線部の各加熱線を単独で通過させるように複数配置される炉内加熱ヒータ用碍子を備え、
それら炉内加熱ヒータ用碍子の隣り合うもの同士が相互に連結可能とされ、連結状態にあるそれら複数の炉内加熱ヒータ用碍子が装着された碍子付き加熱線のアッセンブリの外側に、筒状の金属製の保護カバーが装着されてなる炉内加熱ヒータであって、
それら複数の炉内加熱ヒータ用碍子のうち、先端部に配置される碍子は、前記各セットの二重線部を１本ずつ通す線挿通孔のセットを、基準線の周りに所定の角度間隔で有するベース板部を備えており、
前記線挿通孔のセットは、前記基準線の周りの第１ピッチ円に沿って前記角度間隔で形成される第１線挿通孔と、前記第１ピッチ円に比べて小径の第２ピッチ円に沿って前記第１線挿通孔間の部位に対応するように前記角度間隔で形成される第２線挿通孔とで構成されており、
前記ベース板部の、前記加熱線の各二重線部における折返し先端部側には、前記基準線を含む垂直面に対して傾斜状に突出し、隣り合う折返し先端部同士が短絡しないように前記線挿通孔のセットをセット毎に仕切る仕切り壁が一体に形成されていることを特徴とする炉内加熱ヒータ。 There are a plurality of sets of double line portions that are formed from a heating wire folded back that extends from the base end toward the front end, is folded back at the front end side, and returns to the base end side again. In order to prevent short-circuiting between sets of double wire portions, a plurality of insulators for in-furnace heaters are arranged so as to pass each heating wire of the double wire portion independently from the base end to the tip of the heating wire With
Adjacent ones of the in-furnace heater heaters can be connected to each other, and outside the assembly of the heating wire with the insulator to which the plurality of in-furnace heater heaters are connected, A furnace heater equipped with a metal protective cover,
Among the plurality of in-furnace heater heaters, the insulator disposed at the tip portion is a set of line insertion holes that pass through the double line portions of each set one by one at a predetermined angular interval around the reference line. With a base plate part
The set of the line insertion holes includes a first line insertion hole formed at the angular interval along a first pitch circle around the reference line, and a second pitch circle having a smaller diameter than the first pitch circle. A second line insertion hole formed at the angular interval so as to correspond to a portion between the first line insertion holes,
The base plate portion protrudes in an inclined manner with respect to the vertical plane including the reference line on the folded tip portion side in each double line portion of the heating wire, so that adjacent folded tip portions are not short-circuited. An in-furnace heater, wherein a partition wall for partitioning a set of line insertion holes for each set is integrally formed.

前記仕切り壁の突出端を筒状に繋ぎ、前記折返し先端部のいずれもが前記保護カバーの内周面と短絡しないように前記線挿通孔のセットの全てと該保護カバーの内周面とを仕切る外周壁が一体に形成されている請求項３に記載の炉内加熱ヒータ。 The projecting end of the partition wall is connected in a cylindrical shape, and all of the set of line insertion holes and the inner peripheral surface of the protective cover are connected so that none of the folded tip ends short-circuit with the inner peripheral surface of the protective cover. The in-furnace heater according to claim 3, wherein the partitioning outer peripheral wall is integrally formed.