JPH03654Y2 - - Google Patents

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Publication number
JPH03654Y2
JPH03654Y2 JP6359285U JP6359285U JPH03654Y2 JP H03654 Y2 JPH03654 Y2 JP H03654Y2 JP 6359285 U JP6359285 U JP 6359285U JP 6359285 U JP6359285 U JP 6359285U JP H03654 Y2 JPH03654 Y2 JP H03654Y2
Authority
JP
Japan
Prior art keywords
bushing
pole
transformer
insulator
arc
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
JP6359285U
Other languages
Japanese (ja)
Other versions
JPS61180513U (en
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed filed Critical
Priority to JP6359285U priority Critical patent/JPH03654Y2/ja
Publication of JPS61180513U publication Critical patent/JPS61180513U/ja
Application granted granted Critical
Publication of JPH03654Y2 publication Critical patent/JPH03654Y2/ja
Expired legal-status Critical Current

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  • Housings And Mounting Of Transformers (AREA)
  • Insulators (AREA)

Description

【考案の詳細な説明】 考案の目的 (産業上の利用分野) この考案は柱上変圧器用ブツシングに関するも
のである。
[Detailed description of the invention] Purpose of the invention (field of industrial application) This invention relates to bushings for pole-mounted transformers.

(従来の技術) 従来、柱上変圧器用ブツシングとして、第5図
に示すものが使用されている。このブツシングの
構造を説明すると、柱上変圧器31の接地ケース
31aの側部に外端部を斜め下方にむけてブツシ
ング32が貫通固定され、このブツシング32の
近辺にはブツシング保護金具33が設けられてい
る。前記ブツシング32内に挿通固定された中心
導体34には電線路より引下げた一次側リード線
35の芯線35aが接続されている。
(Prior Art) Conventionally, a bushing shown in FIG. 5 has been used as a bushing for a pole-mounted transformer. To explain the structure of this bushing, a bushing 32 is fixed to the side of the grounding case 31a of the pole-mounted transformer 31 with the outer end facing diagonally downward, and a bushing protection fitting 33 is provided near the bushing 32. It is being A core wire 35a of a primary lead wire 35 drawn down from the electric line is connected to the center conductor 34 inserted and fixed in the bushing 32.

また、中心導体34の先端には前記ブツシング
32外端に形成したスカート部36に囲まれた凹
部36aの前面を覆い、芯線35aを締付固定す
る締付碍子37が螺合固定され、前記スカート部
36との間にアーク放電路C2が形成され、中心
導体34や芯線35aなどよりなる課電部とブツ
シング保護金具33との間に放電間隙が形成され
ている。
Further, a tightening insulator 37 is screwed and fixed to the tip of the center conductor 34 to cover the front surface of a recess 36a surrounded by a skirt 36 formed at the outer end of the bushing 32, and to tighten and fix the core wire 35a. An arc discharge path C2 is formed between the bushing protection fitting 33 and an energized portion made of the center conductor 34, core wire 35a, etc.

柱上変圧器31の一次側リード線35に侵入し
た雷サージによる過電圧は一次側リード線35と
ブツシング保護金具33との間でフラツシオーバ
するが、それに伴う続流は続流自身の電磁力の作
用で前記放電路C2を通る放電間隙で流れるた
め、ブツシング32のスカート部36に囲まれた
凹部36aが続流アークの高熱に曝されて、スカ
ート部36あるいはブツシング32が偏熱破壊し
て変圧器故障となり、停電事故に至る場合が多か
つた。
Overvoltage due to lightning surge that has entered the primary lead wire 35 of the pole transformer 31 flashes over between the primary lead wire 35 and the bushing protective fitting 33, but the accompanying current is caused by the electromagnetic force of the following current itself. Since the current flows in the discharge gap passing through the discharge path C2, the concave portion 36a surrounded by the skirt portion 36 of the bushing 32 is exposed to the high heat of the follow-on arc, and the skirt portion 36 or the bushing 32 is damaged by uneven heat, resulting in damage to the transformer. Failures often occurred, leading to power outages.

(考案が解決しようとする問題点) この考案は前記のような柱上変圧器用ブツシン
グに存する問題点、すなわち、ブツシング32が
雷インパルス電圧のフラツシオーバに伴う続流ア
ークによつて破壊し、柱上変圧器31の故障が発
生するという問題点を解決しようとするものであ
る。
(Problems to be Solved by the Invention) This invention solves the problems that exist in bushings for pole-mounted transformers as described above, namely, the bushing 32 is destroyed by the follow-on arc accompanying the flashover of the lightning impulse voltage, and This is an attempt to solve the problem that the transformer 31 breaks down.

考案の構成 (問題点を解決するための手段) この考案は前記問題点を解決するため、柱上変
圧器1に装着したブツシング2の中心導体13の
端子部13aに締付碍子18を取着し、該締付碍
子18をもつて一次側リード線8を前記端子部1
3aに締付接続してなる柱上変圧器用ブツシング
において、前記ブツシング2と締付碍子18との
間に断熱カバー23を嵌装させるとともに、端子
部13aと電気的に接続した課電部より変圧器の
接地ケース1aに設けたブツシング保護金具25
に至る経路には締付碍子18と断熱カバー23に
挾まれたアーク放電路C1を形成するという構成
を採用している。
Structure of the invention (means for solving the problem) In order to solve the above-mentioned problem, this invention attaches a clamping insulator 18 to the terminal part 13a of the center conductor 13 of the bushing 2 attached to the pole transformer 1. Then, hold the clamping insulator 18 and connect the primary lead wire 8 to the terminal portion 1.
3a, a heat insulating cover 23 is fitted between the bushing 2 and the clamping insulator 18, and the transformer is connected to the terminal section 13a by a power supply section electrically connected to the terminal section 13a. Bushing protection fitting 25 provided on the grounding case 1a of the device
A configuration is adopted in which an arc discharge path C1 sandwiched between a clamping insulator 18 and a heat insulating cover 23 is formed in the path leading to the arc discharge path C1.

(作用) この考案は前記手段を採用したことにより、柱
上変圧器の一次側リード線に侵入した雷サージの
フラツシオーバに伴う続流が、ブツシングのスカ
ート部に囲まれた凹部に嵌装した断熱カバーと締
付碍子との間のアーク放電路を通る放電間隙で流
れても、続流アークの高熱を断熱カバーによつて
遮蔽するので、ブツシングに熱的損傷を与えな
い。
(Function) By adopting the above-mentioned means, this device can prevent the follow-on current caused by the flashover of the lightning surge that has entered the primary lead wire of the pole-mounted transformer into the insulation that is fitted into the recess surrounded by the skirt of the bushing. Even if the arc flows in the discharge gap passing through the arc discharge path between the cover and the clamping insulator, the high heat of the following arc is shielded by the heat insulating cover, so no thermal damage is caused to the bushing.

なお、続流は一次側リード線に接続されている
カツトアウトのヒユーズで遮断されるか、あるい
は変電所で地絡、短絡継電器により遮断器が動作
して遮断される。
The follow-on current is interrupted by a cut-out fuse connected to the primary lead wire, or by a circuit breaker operated by a ground fault or short-circuit relay at the substation.

(実施例) 以下、この考案を具体化した実施例を第1〜第
3図に従つて説明すると、2は図示しない電柱に
設置された柱上変圧器1の接地ケース1aの側部
に外端部を斜め下方にむけて貫通固定されたブツ
シングである。このブツシング2は柱上変圧器1
内に導入され、該柱上変圧器1内において、胴部
に形成した円周溝3aに嵌着したコイルばね7を
介して取付板6により接地ケース1aに固定され
た小径の取付部3と、外端にスカート部5が形成
された大径の胴部4とからなつている。
(Embodiment) Below, an embodiment embodying this invention will be explained with reference to Figs. This is a bushing that is fixed through the end with the end pointing diagonally downward. This bushing 2 is the pole transformer 1
A small-diameter mounting portion 3 is introduced into the pole transformer 1 and is fixed to the grounding case 1a by a mounting plate 6 via a coil spring 7 fitted in a circumferential groove 3a formed in the body. , and a large-diameter body portion 4 having a skirt portion 5 formed at the outer end.

第2,3図に示すようにスカート部5の一側に
は電線路から引下げた一次側リード線8を引込む
ための切欠部5aが形成されている。
As shown in FIGS. 2 and 3, a notch 5a is formed on one side of the skirt portion 5, into which a primary lead wire 8 pulled down from the electric line is drawn.

前記胴部4の基端面と接地ケース1aとの間に
はパツキン9を介在させている。
A packing 9 is interposed between the base end surface of the body portion 4 and the grounding case 1a.

ブツシング2にはスカート部5に囲まれた凹部
10内頂面から取付部3の端部まで挿通孔11が
形成され、この挿通孔11には段部11aが形成
され、また、該段部11aには軸方向に回り止溝
12が設けられている。
An insertion hole 11 is formed in the bushing 2 from the inner top surface of the recess 10 surrounded by the skirt portion 5 to the end of the attachment portion 3, and a step portion 11a is formed in this insertion hole 11. A detent groove 12 is provided in the axial direction.

挿通孔11には先端に雄ねじが螺刻された端子
部13aを有し、ほぼ中央に前記段部11aに当
接して係止される鍔部13bを有する中心導体1
3が挿通され、前記凹部10内頂面でパツキン1
4、平座金15及びばね座金16を介してナツト
17により締付固定されている。また、中心導体
13には前記回り止溝12に対応する突起13c
が形成されていて、中心導体13の締付固定時に
おける回動を防止するようにしている。
The insertion hole 11 has a terminal portion 13a with a male screw threaded at its tip, and the center conductor 1 has a flange portion 13b approximately in the center that abuts and is locked to the step portion 11a.
3 is inserted, and the gasket 1 is inserted at the top surface inside the recess 10.
4. It is tightened and fixed with a nut 17 via a flat washer 15 and a spring washer 16. Further, the center conductor 13 has a protrusion 13c corresponding to the anti-rotation groove 12.
is formed to prevent rotation when the center conductor 13 is tightened and fixed.

前記中心導体13の端子部13aには、直径方
向に一次側リード線8の芯線8aを挿入するため
の長孔13dが貫設されている。
The terminal portion 13a of the center conductor 13 is provided with a long hole 13d through which the core wire 8a of the primary lead wire 8 is inserted in the diametrical direction.

また、中心導体13の端子部13a先端にはブ
ツシング2のスカート部5の前面を覆う締付碍子
18が螺合されていて、前記一次側リード線8の
芯線8aはこの締付碍子18の螺合固定時に平座
金19と皿ばね20などの電極板の間に挾まれて
締付固定される。
Further, a tightening insulator 18 that covers the front surface of the skirt portion 5 of the bushing 2 is screwed onto the tip of the terminal portion 13a of the center conductor 13, and the core wire 8a of the primary lead wire 8 is threaded onto the screw of the tightening insulator 18. When mating and fixing, it is sandwiched between a flat washer 19 and an electrode plate such as a disc spring 20, and is tightened and fixed.

締付碍子18は磁器かゴム、プラスチツクなど
の一般的な絶縁材料、または難燃性絶縁材料、あ
るいはメラミン樹脂やユリア樹脂等の消弧性絶縁
材料よりなる絶縁基台21と、該絶縁基台21の
中央部に固着された螺合筒22とより形成され、
この締付碍子18は螺合筒22により前記端子部
13aに螺合固定されている。
The clamping insulator 18 includes an insulating base 21 made of a general insulating material such as porcelain, rubber, or plastic, or a flame-retardant insulating material, or an arc-extinguishing insulating material such as melamine resin or urea resin, and the insulating base. 21 and a threaded tube 22 fixed to the center thereof,
This tightening insulator 18 is screwed and fixed to the terminal portion 13a by a screw tube 22.

前記スカート部5の凹部10内には第3図に示
す断熱カバー23が嵌装されて前記締付碍子18
との間に放電路C1を形成するとともに、雷イン
パルスフラツシオーバに伴う続流アークが凹部1
0の内壁に触れないようにして続流アークの高熱
によるブツシング2の破壊を防止している。この
断熱カバー23は前記絶縁基台21と同様の材料
よりなり、前記凹部10に嵌入されるほぼ筒状の
カバー本体23aと該カバー本体23aの前端に
形成され、スカート部5の端面に当接されるフラ
ンジ23bよりなる。また、断熱カバー23の一
側には、前記スカート部5の切欠部5aと対応す
るように切欠あるいは貫通孔などの一次側リード
線8の引込口23cが設けられている。
A heat insulating cover 23 shown in FIG. 3 is fitted into the recess 10 of the skirt portion 5, and
A discharge path C1 is formed between the concave portion 1 and the follow-on arc accompanying the lightning impulse flashover
By avoiding contact with the inner wall of the bushing 2, destruction of the bushing 2 due to the high heat of the follow-on arc is prevented. This heat insulating cover 23 is made of the same material as the insulating base 21, and is formed with a substantially cylindrical cover body 23a that is fitted into the recess 10, and a front end of the cover body 23a, and is in contact with the end surface of the skirt portion 5. It consists of a flange 23b. Further, on one side of the heat insulating cover 23, a lead-in port 23c for the primary lead wire 8, such as a notch or a through hole, is provided so as to correspond to the notch 5a of the skirt portion 5.

前記締付碍子18と皿ばね20との間には第3
図に示すように底板部24aと放電筒部24bな
どよりなる放電電極24を端子部13aに嵌装し
ておけば、放電電極24に続流アークが捕捉され
て他の電極部の損傷が防止される。ただし、第4
図に示すように、前記断熱カバー23はフランジ
23bがないもの、また、放電電極24はやや大
径の円輪状金属板などを用いてもブツシング2の
保護あるいは続流アークの所定箇所への捕捉には
充分な効果を発揮できる。
A third plate is provided between the tightening insulator 18 and the disc spring 20.
As shown in the figure, if a discharge electrode 24 consisting of a bottom plate part 24a, a discharge cylinder part 24b, etc. is fitted into the terminal part 13a, a follow-on arc will be captured by the discharge electrode 24, and damage to other electrode parts will be prevented. be done. However, the fourth
As shown in the figure, the heat insulating cover 23 does not have a flange 23b, and the discharge electrode 24 can be made of a circular metal plate with a slightly larger diameter to protect the bushing 2 or trap the follow-on arc at a predetermined location. can be sufficiently effective.

なお、断熱カバー23の先方端を図のように小
径に絞つて電極部分に密着させておけば続流アー
クは断熱カバー23の密着部分へは移行せず、放
電電極24へ集中的に捕捉され、他の電極部分の
損傷を防止できる。
Note that if the front end of the heat insulating cover 23 is narrowed to a small diameter as shown in the figure and brought into close contact with the electrode portion, the follow-on arc will not migrate to the close contact portion of the heat insulating cover 23, but will be intensively captured by the discharge electrode 24. , damage to other electrode parts can be prevented.

柱上変圧器1の接地ケース1aにはブツシング
2の近傍に位置するように平面U字状(第1図二
点鎖線参照)などのブツシング保護金具25が外
力などに対するブツシング2の保護とともに、ホ
ーンを兼ねて設けられている。本考案の実施にあ
たつては、前記ブツシング保護金具25にさらに
補助ホーン25aを続流アーク捕捉のため突設す
るか、あるいは平面U字状の頂部を切断しておけ
ば、さらに続流アークを捕捉し易くなる。
In the grounding case 1a of the pole-mounted transformer 1, a bushing protection fitting 25, such as a U-shaped planar shape (see the two-dot chain line in FIG. 1), is located near the bushing 2 to protect the bushing 2 from external forces, etc., and to protect the bushing 2 from external forces. It is also set up as In carrying out the present invention, if an auxiliary horn 25a is further provided protruding from the bushing protective fitting 25 to capture the follow-on arc, or the top of the planar U-shape is cut off, the follow-on arc can be further prevented. becomes easier to capture.

次に、本考案の作用について説明する。 Next, the operation of the present invention will be explained.

一次側リード線8に侵入した雷サージ等による
過電圧は中心導体13の端子部13aなどの課電
部とブツシング保護金具25との間でフラツシオ
ーバし、これに伴なつて続流放電するが、続流ア
ークは続流自身の電磁力により放電路C1を通る
放電間隙を流れ、断熱カバー23により遮蔽され
ている凹部10内壁に対する熱影響はほとんどな
く、ブツシング2の偏熱破壊が防止される。
Overvoltage caused by a lightning surge or the like that has entered the primary lead wire 8 flashes over between the terminal section 13a of the center conductor 13 and the bushing protective fitting 25, resulting in a follow-up discharge. The current arc flows through the discharge gap passing through the discharge path C1 due to the electromagnetic force of the following current, and there is almost no thermal influence on the inner wall of the recess 10 that is shielded by the heat insulating cover 23, and uneven heat damage to the bushing 2 is prevented.

また、締付碍子18の絶縁基台21あるいは断
熱カバー23をとくに前記のように難燃性絶縁材
料で形成しておけば、続流アークによる着火、延
焼を防止でき、また、消弧性絶縁材料をもつて形
成しておけば、続流アークの高熱によつてこれら
の材料が熱分解され、放電路C1内には消弧性ガ
スが発生し、続流アークの消弧能力を生じる。従
つて、締付碍子18の絶縁基台21と断熱カバー
23はそれぞれ上記の材料を使いわけることによ
つても優れた効果を発揮できる。
Furthermore, if the insulating base 21 or the heat insulating cover 23 of the clamping insulator 18 is made of a flame-retardant insulating material as described above, ignition and fire spread due to follow-on arc can be prevented, and arc-extinguishing insulation If the discharge path C1 is made of materials, these materials will be thermally decomposed by the high heat of the trailing arc, and arc-extinguishing gas will be generated in the discharge path C1, resulting in the ability to extinguish the trailing arc. Therefore, superior effects can be achieved by using the above-mentioned materials for the insulating base 21 and the heat insulating cover 23 of the clamping insulator 18, respectively.

また、本考案では締付碍子18と皿ばね20な
どの電極板との間に嵌装させた放電電極24の底
板部24aの厚さを変えることにより放電路C1
の幅を容易に変更することができる。
Further, in the present invention, by changing the thickness of the bottom plate part 24a of the discharge electrode 24 fitted between the clamping insulator 18 and the electrode plate such as the disc spring 20,
The width can be easily changed.

さらに、断熱カバー23および放電電極24は
既設の柱上変圧器ブツシングへの取付けを容易に
行うことができ、また、締付碍子18と断熱カバ
ー23との間に形成する放電路C1は屈折し、か
つ、細隙にできるため、感電の危険がなく、かつ
鳥害事故も防止できる。
Furthermore, the heat insulating cover 23 and the discharge electrode 24 can be easily attached to an existing pole transformer bushing, and the discharge path C1 formed between the clamping insulator 18 and the heat insulating cover 23 can be bent. , and because it is created in a narrow gap, there is no risk of electric shock and accidents caused by birds can be prevented.

考案の効果 以上詳述したように、本考案によれば柱上変圧
器の一次側リード線に雷サージが侵入して変圧器
用ブツシングでフラツシオーバしても、続流アー
クの高熱を断熱カバーによつて遮蔽して熱影響を
ほとんどなくしてブツシングの破損を防止できる
ので、柱上変圧器の雷害事故を大巾に減少させ
て、電力の安定供給を図ることができる。
Effects of the invention As detailed above, according to the invention, even if a lightning surge enters the primary lead wire of a pole-mounted transformer and the transformer bushing flashes over, the high heat of the follow-on arc is absorbed by the heat insulating cover. Since the bushings can be shielded and shielded to almost eliminate thermal effects and damage to the bushings, lightning damage to pole-mounted transformers can be greatly reduced and a stable supply of power can be achieved.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図はこの考案を具体化した一実施例を示す
断面図、第2図は同じく正面図、第3図はスカー
ト部付近の分解斜視図、第4図は別の実施例を示
す分解斜視図、第5図は従来例を示す一部断面図
である。 1……柱上変圧器、1a……接地ケース、2…
…ブツシング、5……スカート部、8……一次側
リード線、13……中心導体、18……締付碍
子、23……断熱カバー、25……ブツシング保
護金具、C1……放電路。
Fig. 1 is a sectional view showing an embodiment embodying this invention, Fig. 2 is a front view, Fig. 3 is an exploded perspective view of the vicinity of the skirt, and Fig. 4 is an exploded perspective view showing another embodiment. FIG. 5 is a partial sectional view showing a conventional example. 1...Pole transformer, 1a...Grounding case, 2...
... Bushing, 5 ... Skirt portion, 8 ... Primary side lead wire, 13 ... Center conductor, 18 ... Tightening insulator, 23 ... Heat insulation cover, 25 ... Bushing protection fitting, C1 ... Discharge path.

Claims (1)

【実用新案登録請求の範囲】 1 柱上変圧器1に装着したブツシング2の中心
導体13の端子部13aに締付碍子18を取着
し、該締付碍子18をもつて一次側リード線8
を前記端子部13aに締付接続してなる柱上変
圧器用ブツシングにおいて、前記ブツシング2
と締付碍子18との間に断熱カバー23を嵌装
させるとともに、端子部13aと電気的に接続
した課電部より変圧器の接地ケース1aに設け
たブツシング保護金具25に至る経路には締付
碍子18と断熱カバー23に挾まれたアーク放
電路C1を形成したことを特徴とする柱上変圧
器用ブツシング。 2 中心導体13は端子部13aに放電電極24
を備えている実用新案登録請求の範囲第1項に
記載の柱上変圧器用ブツシング。
[Claims for Utility Model Registration] 1. A clamping insulator 18 is attached to the terminal portion 13a of the center conductor 13 of the bushing 2 attached to the pole transformer 1, and the primary lead wire 8 is connected with the clamping insulator 18.
In the bushing for a pole-mounted transformer, which is formed by tightening and connecting the bushing 2 to the terminal portion 13a,
A heat insulating cover 23 is fitted between the terminal section 13a and the clamping insulator 18, and a clamping section is provided on the path leading from the energizing section electrically connected to the terminal section 13a to the bushing protective fitting 25 provided on the grounding case 1a of the transformer. A bushing for a pole transformer characterized by forming an arc discharge path C1 sandwiched between an insulator 18 and a heat insulating cover 23. 2 The center conductor 13 has a discharge electrode 24 on the terminal portion 13a.
A bushing for a pole-mounted transformer according to claim 1 of the utility model registration claim, comprising:
JP6359285U 1985-04-27 1985-04-27 Expired JPH03654Y2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6359285U JPH03654Y2 (en) 1985-04-27 1985-04-27

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6359285U JPH03654Y2 (en) 1985-04-27 1985-04-27

Publications (2)

Publication Number Publication Date
JPS61180513U JPS61180513U (en) 1986-11-11
JPH03654Y2 true JPH03654Y2 (en) 1991-01-11

Family

ID=30593884

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6359285U Expired JPH03654Y2 (en) 1985-04-27 1985-04-27

Country Status (1)

Country Link
JP (1) JPH03654Y2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0639443Y2 (en) * 1989-09-26 1994-10-12 東京電力株式会社 Gas insulated transformer

Also Published As

Publication number Publication date
JPS61180513U (en) 1986-11-11

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