JP2004080932A

JP2004080932A - Tube-heating device and sealing method for wire connecting part

Info

Publication number: JP2004080932A
Application number: JP2002239273A
Authority: JP
Inventors: Masaaki Kobayashi; 小林　正明
Original assignee: Yazaki Corp
Current assignee: Yazaki Corp
Priority date: 2002-08-20
Filing date: 2002-08-20
Publication date: 2004-03-11
Anticipated expiration: 2022-08-20
Also published as: JP3940337B2

Abstract

<P>PROBLEM TO BE SOLVED: To surely adhere a heat-shrinkable tube by easily coping with connecting parts of the middle and the end of a wire. <P>SOLUTION: A tube heating device 1 is employed which comprises a pair of chucks 5 that grip the wire of an assembly composed of the heat-shrinkable tube and the wire; a heating bath 2, having an insertion part 18 that inserts the assembly in a wire diametral direction; and a mechanism 4 that advances and retreats the pair of chucks along the heating bath 2. A product-collecting member 6 is arranged so as to freely advance and retreat, comprising a slope 25 for picking up the wire between the pair of chucks 5 and a product receiving part 26 succeeding to the inclined part. A tube-holding jig is fixable to one of the pair of chucks 5, and the tube holding jig is constituted of a cylinder to which the tip of the heat-shrinkable tube is inserted, a shaft that succeeds to the cylinder and is positioned around the chuck, and a chuck-fixing part arranged to the shaft. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、電線相互の中間接続部や端末接続部に合成樹脂製の熱収縮チューブを被着させて電線接続部の絶縁保護を図るチューブ加熱装置及び電線接続部の密封方法に関するものである。
【０００２】
【従来の技術】
図６〜図８は、従来の電線接続部の密封方法及びチューブ加熱装置の一形態を示すものである。
【０００３】
図６は、複数本の電線４５の端末部を熱溶着で接続し、その接続部４６を柔軟な合成樹脂製の熱収縮チューブ４７の内側に挿入した状態を示すものである。熱収縮チューブ内には予めホットメルト接着剤４８やブチルゴム等のシール剤４９が注入されている。ホットメルト接着剤４８は筒状の熱収縮チューブ４７の一端を封止している。
【０００４】
図７は、熱収縮チューブ４９の内面に沿ってホットメルト接着剤５０を塗布し、そのチューブ内に電線５１の端末の熱溶着接続部５２を挿入した状態を示すものである。
【０００５】
図８は、これら熱収縮チューブ４７に電線４５の端末接続部を挿入したセット品（組付品）をチューブ加熱装置５３の内部にセットし、電線４５をローラ５４で径方向に送り、熱収縮チューブ４７をヒータ５５で加熱して収縮させつつ、チューブ内部のホットメルト接着剤４８やシール剤４９を溶融させて各電線４５間に入り込ませて、電線接続部４６の絶縁及び防水を図るものである。
【０００６】
図７の熱収縮チューブ４９の先端を棒状のチューブ保持治具（図示せず）の先端の筒状部内に挿入した状態で、熱収縮チューブ４９をチューブ加熱装置で加熱収縮させ、チューブ先端からのホットメルト接着剤５０の流出を防止する構造も本出願人によって特開平１１−１７８１４４号で提案されている。
【０００７】
【発明が解決しようとする課題】
しかしながら、上記従来の電線接続部の密封方法やチューブ加熱装置にあっては、電線４５をローラ５４で挟みつつ加熱槽５６内に搬送するものであるために、熱収縮チューブ４７の位置が加熱槽内でずれたり偏心したりしやすく、熱収縮チューブ４７の収縮度合やチューブ内のホットメルト接着剤４８等の溶融度合にばらつきを生じやすく、電線接続部４６の密封性が悪化するという懸念があった。
【０００８】
また、上記従来の密封方法及び加熱装置は電線４５の端末接続部４６のみを絶縁・防水するものであり、電線を長手方向に突き合わせて溶着接続した中間接続部の絶縁・防水を図ることはできなかった。そのため、端末接続部用と中間接続部用の二種類のチューブ加熱装置を必要とし、工程が肥大化すると共に設備費が高くつくという問題があった。
【０００９】
本発明は、上記した点に鑑み、電線や熱収縮チューブの位置ずれ等なく電線の接続部を正確に絶縁保護させることができ、それに加えて完成品（電線とチューブとの組付品）を効率的に回収でき、さらに、一つのチューブ加熱装置で電線の端末接続部と中間接続部との何れでも効率的に絶縁保護させることのできるチューブ加熱装置及び電線接続部の密封方法を提供することを目的とする。
【００１０】
【課題を解決するための手段】
上記目的を達成するために、本発明の請求項１に係るチューブ加熱装置は、電線接続部を覆う熱収縮チューブと電線とで成る組付品の該電線を把持する一対のチャック部と、該組付品を電線径方向に挿入する挿通部を有する加熱槽と、該一対のチャック部を該加熱槽に沿って進退させる機構とを備えることを特徴とする。
上記構成により、中間の電線接続部を有する組付品の場合、電線接続部の両側に延びる電線が一対のチャック部で把持され、チャック部の後退動作で組付品の熱収縮チューブが加熱槽内に送られて所要温度で所要時間加熱される。これにより、熱収縮チューブが収縮されて電線接続部の外周面に密着し、電線接続部が絶縁保護される。熱収縮チューブ内にホットメルト接着剤を装填した場合は、ホットメルト接着剤が溶けて各電線間やチューブと電線との間に隙間なく充填される。チャック部の前進動作で組付品が加熱槽の外に出され、空冷されつつチャックの開放により取り出される。
【００１１】
請求項２に係るチューブ加熱装置は、請求項１記載のチューブ加熱装置において、前記一対のチャック部の間で前記電線に対する拾い上げ用の傾斜部と、該傾斜部に続く製品受け部とを有する製品回収部材が進退自在に配置されたことを特徴とする。
上記構成により、チャック部が開きつつ、製品回収部材が上昇して傾斜部で電線を持ち上げてチャック部から開放させ、電線は傾斜部に沿って製品受け部に自動的に落下する。
【００１２】
請求項３に係るチューブ加熱装置は、請求項１又は２記載のチューブ加熱装置において、前記一対のチャック部の一方にチューブ保持治具を固定可能であり、該チューブ保持治具は、前記熱収縮チューブの先端を挿入する筒状部と、該筒状部に続き、チャック中心に位置する軸部と、該軸部に設けられたチャック固定部とで構成されることを特徴とする。
上記構成により、軸部が一方のチャック中心に位置し、他方のチャックで把持された電線と同軸に位置する。筒状部も電線と同軸に位置し、筒状部で保持された熱収縮チューブが電線と同軸に位置する。これにより、熱収縮チューブの径方向の位置が正確に規定される。熱収縮チューブの軸方向の位置は、軸部をチャック部に固定した際に熱収縮チューブが一対のチャック部の中央に位置するように軸部の長さを設定しておくことで、正確に規定される。チャック部を開いても、チューブ保持治具がチャック部から落ちないから、保持治具からの電線とチューブとの組付品の取外しが容易であり、且つ次のチューブを保持治具に迅速にセットすることができる。
【００１３】
請求項４に係るチューブ加熱装置は、請求項３記載のチューブ加熱装置において、前記チャック固定部が前記チャック部側の係止部に係合する係合部を有することを特徴とする。
上記構成により、チャック固定部をワンタッチでチャック部側に係止させることができ、チューブ保持治具の脱着が容易化、迅速加する。
【００１４】
請求項５に係る電線接続部の密封方法は、熱収縮チューブで覆う長手方向中間の電線接続部に続く両側の電線を一対のチャック部で把持し、該一対のチャック部を後退させて該熱収縮チューブを加熱槽内に進入させ、該熱収縮チューブを加熱して収縮させた後、該一対のチャック部を前進させて該熱収縮チューブを加熱槽外に露出させて冷却し、該一対のチャックを開いて該電線を解放することを特徴とする。
上記構成により、中間の電線接続部を有する組付品の場合、電線接続部の両側に延びる電線が一対のチャック部で把持され、チャック部の後退動作で組付品の熱収縮チューブが加熱槽内に送られて所要温度で所要時間加熱される。これにより、熱収縮チューブが収縮されて電線接続部の外周面に密着し、電線接続部が絶縁保護される。熱収縮チューブ内にホットメルト接着剤を装填した場合は、ホットメルト接着剤が溶けて各電線間やチューブと電線との間に隙間なく充填される。チャック部の前進動作で組付品が加熱槽の外に出され、空冷されつつチャックの開放により取り出される。
【００１５】
請求項６に係る電線接続部の密封方法は、請求項５記載の電線接続部の密封方法において、前記一対のチャック部で前記電線を把持する際に、前記電線接続部を第一の合わせマークに位置合わせし、該一対のチャック部で該電線を把持した後、前記熱収縮チューブを電線長手方向に移動して第二の合わせマークに位置合わせすることを特徴とする。
上記構成により、先ず、電線接続部が一対のチャック部の中間に正確に位置決めされ、次いで熱収縮チューブが電線長手方向にスライドしつつ位置決めされて電線接続部を正確に覆う。これにより、熱収縮チューブが加熱槽の中央に配置され、ばらつきなく正確に収縮する。
【００１６】
請求項７に係る電線接続部の密封方法は、請求項５又は６記載の電線接続部の密封方法において、前記一対のチャックを開いた際に、製品回収部材で前記電線を持ち上げつつ該一対のチャックから外して完成品を製品受け部に落下させることを特徴とする。
上記構成により、組付品が製品回収部材によって自動的にチャック部から離脱されて製品受け部に回収される。
【００１７】
請求項８に係る電線接続部の密封方法は、請求項５記載の電線接続部の密封方法において、前記一対のチャック部の一方にチューブ保持治具を固定し、該チューブ保持治具に端末の電線接続部用の熱収縮チューブを保持させ、該端末の電線接続部に続く電線を該一対のチャック部の他方で把持させ、前記中間の電線接続部用の熱収縮チューブに代えて該端末の電線接続部用の熱収縮チューブを前記加熱槽で加熱することを特徴とする。
上記構成により、一方のチャック部にチューブ保持治具が固定され、チューブ保持治具に熱収縮チューブが保持され、熱収縮チューブ内には端末の電線接続部が挿入され、他方のチャック部に電線が把持される。その状態で、両チャック部が後退し、熱収縮チューブが加熱槽内に進入して加熱され、チューブの収縮後及び／又はチューブ内のホットメルト接着剤の溶融後に、両チャック部の前進動作で組付品が加熱槽の外に出されて冷却される。両チャック部が開き、電線は解放され、保持部材はチャック部に固定されたまま残り、作業者が組付品を保持部材から外す。
【００１８】
【発明の実施の形態】
以下に本発明の実施の形態を図面に基づいて詳細に説明する。
図１〜図２は、本発明に係るチューブ加熱装置の一実施形態を示すものである（図１は正面図、図２は側面図）。
【００１９】
図１，図２のチューブ加熱装置１において、符号２は加熱槽、３は制御盤、４は、加熱槽２に対して電線と熱収縮チューブとのセット品（組付品）１４，１５（図３，図４）を進退させる左右一対のスライド部、５は、各スライド部４に設けられた左右一対のチャック部、６（図２）は、チャック部５から電線と熱収縮チューブとの組付品（熱収縮完了品又は製品）を強制的に回収する昇降自在な製品回収部材をそれぞれ示すものである。
【００２０】
加熱槽２内にはヒータ（図示せず）が装着され、下側にファン２４が設けられている。加熱槽２の左右の壁部（側壁）１６と前側の壁部１７とを貫通して水平方向のスリット状の挿通部１８が設けられ、前側の壁部１７に挿通部１８の前部開口１８ａが位置している。前部開口１８ａに連通する各側壁１６のスリット部１８ｂの外側（加熱槽２の外側）にスライド部４が位置している。スライド部４は左右一対の垂直な支柱部１９と、支柱部１９を支える水平な基板部２０とで構成され、基板部２０が例えば加熱槽下側の水平なレール（図示せず）にスライド自在に係合している。
【００２１】
支柱部１９の先端にチャック部５が固定されている。チャック部５の中心は前部開口１８ａやスリット部１８ｂの中心と水平方向の同一平面上に位置している。一対のチャック部５は加熱槽２の外側において左右に対向して対称に（前後の位置ずれなく同一高さに）位置している。
【００２２】
チャック部５は上下一対のチャック片で構成され、エア式のシリンダ２２によって上下方向に開閉自在である。左右一対のチャック部５で複数本の電線の両端部又は長手方向中間部の二カ所を把持する。チャック部５を構成する上下のチャック片２１は図３に示す如く略Ｖ字状の複数の把持爪２３を有している。上下の把持爪２３は交互に噛み合って複数本の電線７，８を確実に把持する。
【００２３】
図３の形態において、電線７，８は長手方向中間部に溶着接続部９を有している。この接続部９は左右の各複数の電線７，８の端末を相互に突き合わせた状態（正確には上下に重ね合わせた状態）で電線径方向に電極（図示せず）で熱溶着させたものである。電線接続部９の外側には合成樹脂製の柔軟な熱収縮チューブ１０が装着されている。熱収縮チューブ１０の内側にはホットメルト接着剤及び／又はシール剤（図示せず）が装填されている。この熱収縮チューブ１０は円筒状のもので、左右端に開口１０ａを有している。
【００２４】
左右のチャック部５の中央位置に電線接続部９と熱収縮チューブ１０とがくるように位置合わせされている。例えば図２の前側の昇降自在な製品回収部材６に電線接続部９の位置決めマークと熱収縮チューブ１０の位置決めマークとを印しておくことで、両者の位置が正確に規定され、熱収縮チューブ１０の熱収縮がばらつきなく正確に行われる。すなわち、加熱槽２内の左右と中央とでは温度がやや異なりやすいが、熱収縮チューブ１０が常に加熱槽２の中央にくるように位置合わせされるから、製品ごとの収縮ムラが起こらない。
【００２５】
図２の製品回収部材６は、金属板を屈曲して形成され、上側の傾斜部２５と、傾斜部２５の下側に続く製品受け部２６とを備えており、加熱装置１の水平な基台２７に固定された垂直なエアシリンダ（駆動部）２８のロッド２８ａに固定されて昇降自在である。傾斜部２５は左右一対設けられ、一対の傾斜部２５の間に熱収縮チューブ１０とその近傍の電線７，８を逃がすための孔部（図示せず）が構成され、傾斜部２５の上端に水平部２９が続き、水平部２９に前記電線接続部９や熱収縮チューブ１０に対する位置合わせマークが印されている。製品受け部２６は傾斜部２５に続く垂直部２６ａと、垂直部２６ａに続く水平部（２６で代用）と、水平部に続く、前向き傾斜部２６ｂとで略凹字状に構成されている。
【００２６】
傾斜部２５は前から後上がりに傾斜し、傾斜部２５の上端はチャック部５の電線把持中心よりも少し後方（加熱槽寄り）に位置している。加熱槽２の前方にシリンダ２８が位置し、シリンダロッド２８ａは製品回収部材６の中間の垂直部２６ａに固定されている。製品回収部材６の形状は適宜設定可能であり、例えば傾斜部２５を板状ではなく棒状に形成することも可能である。チャック部５から解放された電線７，８（図３）を、上昇する傾斜部２５で拾い上げて製品受け部２６に落下させる。
【００２７】
図１の制御盤３は加熱槽２の後方に立設され、運転スイッチ３０や温度調節部３１や加熱時間設定部３２や各種の表示ランプ（運転ランプや異常ランプ等）３３を備えている。運転スイッチ３０を入れることで、ヒータが加熱され、加熱槽２が所定温度（３５０゜程度である）に達すると、作業開始ＯＫのランプ３３が点灯する。以下に電線接続部９の密封方法について説明する。
【００２８】
図３において作業者は両方の電線７，８を両手で持って電線接続部９を第一の合わせマークに位置合わせし、フットスイッチを踏んで左右のチャック部５に電線７，８を把持させる。電線接続部９が見えるように熱収縮チューブ１０は電線接続部９の横（電線長手方向）にずらしておく。次いで熱収縮チューブ１０を第二の合わせマークに位置合わせして電線接続部９の外周上にくるように長手方向に移動する。電線接続部９は熱収縮チューブ１０で完全に覆われる。
【００２９】
次いでフットスイッチを踏んでスライド部４（図１，図２）を後退させ、チャック部５に把持された電線７，８の中央（熱収縮チューブ１０が位置する部分）とその近傍の部分を加熱槽２内に進入させる。所要時間（１０秒程度である）が経過した後、自動的にスライド部４が前進し、熱収縮チューブ１０と電線７，８との組付品１４が加熱槽２の外側に出される。熱収縮チューブ１０は加熱により径方向に収縮し、ホットメルト接着剤等を介して電線７，８とその接続部９とに隙間なく密着する。熱収縮チューブ１０は電線７，８をチャックされたまま外部に出されることで、短い時間ではあるが自然冷却される。冷却時間は適宜設定可能である。エアブロー等で強制冷却することも可能である。
【００３０】
チャック部５が自動的に開きつつ、垂直なシリンダ２８（図２）が伸長して製品回収部材６の傾斜部（傾斜面）２５が左右のチャック部５の間で電線７，８をチャック中心よりも高く持ち上げることで、傾斜部２５に沿って製品（電線７，８とチューブ１０との組付完成品）が製品受け部２６に滑り落ちる。作業者は製品受け部２６から製品を拾って例えばパレットに入れ、次工程へ運ぶ。製品受け部２６にある程度の数の組付完成品を溜めつつ自然冷却させることも可能である。
【００３１】
図４は、電線１１の端末の接続部１２に収縮チューブ１３を被着させる構成例を示すものである。チューブ加熱装置１は図１，図２と同じものを使用する。
【００３２】
図４で、符号３５はチューブ保持治具を示す。チューブ保持治具３５は金属で形成され、中実で真直な細い軸部３６の先端に、軸部３６よりも大径な中空の筒状部３７を同心に設けたものであり、軸部３６は左右何れか一方のチャック部５に固定され、筒状部３７に熱収縮チューブ１３の先端の小径部１３ａが嵌合保持される。軸部３６は下側のチャック片２１に例えば固定板（固定部）３８と固定軸３９とで固定されている。熱収縮チューブ１３の形態は従来例の図７に示すものと同様である。
【００３３】
図５（ａ）（ｂ）にチューブ保持治具３５の一実施形態を示す如く、軸部３６の後端と長手方向中間部とに一対の鍔状の固定板（固定部）３８が軸径方向に突出して設けられ、一対の固定板３８は対向して位置し、固定板３８の上端寄りに軸部３６が貫通固定され、固定板３８の各内面の下端寄りにおいて半球状の凹部４０が対向して設けられ、各凹部４０に真直な固定軸３９の各端部３９ａが係合可能となっている。固定軸３９の両端部３９ａは半球状の面で形成されている。筒状部３７の内側には円形の孔部４１が設けられ、孔部４１の入口にガイドテーパ面が形成されている。
【００３４】
図４で、下側のチャック片２１に固定軸３９を挿通させる水平な孔部４２（図３）が設けられ、孔部４２に固定軸３９を挿通させ、固定軸３９の半球状の各端部（係止部）３９ａを孔部４２から外側に突出させた状態で、チャック片２１の左右の端面に各固定板３８（図５）の内面を摺接させ、チャック部５のチャック中心に軸部３６をセットしつつ、固定板３８の凹部（係合部）４０に固定軸３９の端部３９ａを進入係合させることで、軸部３６がチャック片２１に固定される。軸部３６は上下のチャック片２１で把持されてチャック中心に位置する。
【００３５】
なお、固定軸３９に代えてチャック片２１にボールプランジャ（係止部）を設け、突出方向にばね付勢されたボールを固定板３８の凹部（係合部）４０に係合させることも可能である。また、合成樹脂製のチャック片２１の側端面に一体に半球状や傾斜状の突起（係止部）を設け、固定板３８の凹部（係合部）４０に突起を係止させることも可能である。
【００３６】
これらの手段で下側のチャック片２１にチューブ保持治具３５を固定させることで、チャック部５を開いてもチューブ保持治具３５が落下せずにチャック中心に保持されるから、完成した製品すなわち電線１１と熱収縮チューブ１３との組付品をチャック部５の開閉に関係なく常にチャック中心に保持させることができて、取外し作業性が良好となると共に、製品をチューブ保持治具３５から取り外した後、次の熱収縮チューブ１３を筒状部３７に迅速に嵌合セットすることができて、熱収縮チューブ１３のセット作業性が向上する。また、チューブ保持治具３５の筒状部３７の位置が常に一定に規定されているから、熱収縮チューブ１３の位置合わせを行う必要がなく、筒状部３７に熱収縮チューブ１３を嵌合させれば常に熱収縮チューブ１３の位置が左右のチャック部５の中央に位置し、チューブ１３の熱収縮が加熱槽２の中央でばらつきなく安定して行われる。
【００３７】
なお、一方のチャック部５にチューブ保持治具３５を固定させる代わりに、保持治具３５の軸部３６を常に一方のチャック部５で把持しておく（一方のチャック部５を常に閉じておき、他方のチャック部５のみをフットスイッチ等で開閉自在とする）ことも可能である。
【００３８】
以下に図４の形態の電線１１とチューブ１３との組付品１５を用いた場合の電線接続部の密封方法を順を追って説明する。
【００３９】
先ず、図２のチューブ加熱装置１の一方のチャック部５（右効きの作業者が多いので左側のチャック部が好ましい）にチューブ保持治具３５を上記要領で固定する。加熱槽２が所定温度になったら、チューブ保持治具３５の先端側の筒状部３７に熱収縮チューブ１３の一端１３ａを挿入保持させ、チューブ１３の開口１３ｂからチューブ内に電線１１の端末接続部１２を挿入し、両チャック部５を閉じて電線１１を他方のチャック部５で把持させる。チューブ保持治具３５は他方のチャック部５でしっかりと把持固定される。
【００４０】
次いでスイッチ操作又は自動（シーケンス制御等）で両チャック部５をスライド部４と共に後退させ、熱収縮チューブ１３を加熱槽２内に進入させ、所要時間加熱する。加熱により、熱収縮チューブ内のホットメルト接着剤が溶融して各電線１１間の隙間に充填されると共に、熱収縮チューブ１３が収縮して電線１１の外周面にホットメルト接着剤を介して隙間なく密着する。加熱が完了したら、両チャック部５を電線１１とチューブ１３との組付品と共に前進させ、組付品を自然冷却しつつ、チャック部５を開く。
【００４１】
作業者が例えば熱収縮チューブ１３を持ってチューブ保持治具３５から製品を外し、製品回収部（図示せず）にストックする。チューブ保持治具３５は一方のチャック部５に固定されているから、チャック部５を開いても外れることがなく、次の熱収縮チューブ１３をチューブ保持治具３５に迅速にセットすることができる。
【００４２】
熱収縮チューブ１３のセット位置はチューブ保持治具３５をチャック部５に固定することで規定されるので、作業者は目視で熱収縮チューブ１３の位置合わせをする必要がなく、常に正確に熱収縮チューブ１３の位置が規定される。チューブ内の電線接続部１２の位置決めは電線接続部１２の先端を熱収縮チューブ１３の底部内面に突き当てることで行われる。
【００４３】
なお、上記各実施形態において、熱収縮チューブ内にホットメルト接着剤等を装填することなく熱収縮チューブ１０，１３を電線接続部９，１２に熱収縮のみで被着させることも可能である。また、電線１１と熱収縮チューブ１３との組付品１５を水平ではなく垂直にして加熱槽内に進入させるように、加熱槽２の挿通部１８を垂直方向に設けることも可能である。この場合、熱収縮チューブ１３の封止された先端側を下向き、開口１３ｂ側を上向きとする。
【００４４】
【発明の効果】
以上の如く、請求項１記載の発明によれば、電線が一対のチャック部で把持されるから、熱収縮チューブの位置が一対のチャック部の間で振れや位置ずれなく正確に規定され、加熱槽の中央位置に熱収縮チューブが投入されて、加熱温度のばらつきなく、常に正確に収縮される。これにより、電線接続部の絶縁や防水等の保護が確実に行われ、絶縁保護の信頼性が向上する。
【００４５】
請求項２記載の発明によれば、製品回収部材によって電線と熱収縮チューブとの組付品をチャック部から自動的に回収できるから、作業者による回収作業が不要となり、組付品の生産性が向上する。
【００４６】
請求項３記載の発明によれば、チューブ保持治具を選択的に使用することで、一つのチューブ加熱装置を用いて電線の中間接続部と端末接続部との両方に対応して熱収縮チューブを被着させることができる。これにより、従来、二台必要であった加熱装置が一台で済むようになり、装置の設置スペースの削減とコスト削減が可能となる。また、チューブ保持治具はチャック部に固定されて、チャック部を開いても落ちないから、効率的に保持治具に対する熱収縮チューブの着脱作業を行うことができ、作業性が向上する。また、保持治具の軸部がチャック中心に位置して熱収縮チューブが電線と同心に位置することで、チューブの熱収縮性が高まり、チューブが電線に隙間なく密着し、絶縁性や防水性が一層向上する。
【００４７】
請求項４記載の発明によれば、チャック部に対するチューブ保持治具の脱着を容易に且つ迅速に行うことができるから、中間接続部用から端末接続部用への段取を効率的に行うことができる。
【００４８】
請求項５記載の発明によれば、電線が一対のチャック部で把持されるから、熱収縮チューブの位置が一対のチャック部の間で振れや位置ずれなく正確に規定され、加熱槽の中央位置に熱収縮チューブが投入されて、加熱温度のばらつきなく、常に正確に収縮される。これにより、電線接続部の絶縁や防水等の保護が確実に行われ、絶縁保護の信頼性が向上する。
【００４９】
請求項６記載の発明によれば、加熱槽に対する電線接続部の位置と熱収縮チューブの位置とを正確に規定することができるから、熱収縮チューブが加熱槽の中央でばらつきなく正確に収縮し、電線接続部の絶縁性・保護性が一層向上する。
【００５０】
請求項７記載の発明によれば、製品回収部材によって電線と熱収縮チューブとの組付品をチャック部から自動的に回収できるから、作業者による回収作業が不要となり、組付品の生産性が向上する。
【００５１】
請求項８記載の発明によれば、チューブ保持治具を選択的に使用することで、一つのチューブ加熱装置を用いて電線の中間接続部と端末接続部との両方に対応して熱収縮チューブを被着させることができる。これにより、従来、二台必要であった加熱装置が一台で済むようになり、装置の設置スペースの削減とコスト削減が可能となる。また、チューブ保持治具はチャック部に固定されて、チャック部を開いても落ちないから、効率的に保持治具に対する熱収縮チューブの着脱作業を行うことができ、作業性が向上する。
【図面の簡単な説明】
【図１】本発明に係るチューブ加熱装置の一実施形態を示す正面図である。
【図２】同じくチューブ加熱装置を示す側面図である。
【図３】中間接続部を有する組付品を一対のチャックで把持した状態を示す要部斜視図である。
【図４】端末接続部を有する組付品をチューブ保持治具を介してチャックに固定した状態を示す要部斜視図である。
【図５】チューブ保持治具の一実施形態を示し、（ａ）は一部を断面とした側面図、（ｂ）は正面図である。
【図６】従来の電線の端末接続部に熱収縮チューブをセットした一形態を示す断面図である。
【図７】同じく電線の端末接続部に熱収縮チューブをセットした他の形態を示す断面図である。
【図８】従来のチューブ加熱装置の一形態を示す断面図である。
【符号の説明】
１　　　　　　チューブ加熱装置
２　　　　　　加熱槽
４　　　　　　スライド部（進退機構）
５　　　　　　チャック部
６　　　　　　製品回収部材
７，８，１１　電線
９，１２　　　電線接続部
１０，１３　　熱収縮チューブ
１４，１５　　組付品
１８　　　　　挿通部
２５　　　　　傾斜部
２６　　　　　製品受け部
３５　　　　　チューブ保持治具
３６　　　　　軸部
３７　　　　　筒状部
３８　　　　　固定板（チャック固定部）
３９ａ　　　　端部（係止部）
４０　　　　　凹部（係合部）[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tube heating device for attaching a heat-shrinkable tube made of a synthetic resin to an intermediate connection portion or a terminal connection portion between electric wires to protect the electric wire connection portion from insulation, and to a method for sealing the electric wire connection portion.
[0002]
[Prior art]
6 to 8 show an embodiment of a conventional method for sealing a wire connection portion and a tube heating device.
[0003]
FIG. 6 shows a state in which the end portions of a plurality of electric wires 45 are connected by heat welding, and the connection portions 46 are inserted inside a heat-shrinkable tube 47 made of a flexible synthetic resin. A sealing agent 49 such as a hot melt adhesive 48 or butyl rubber is injected into the heat shrink tube in advance. The hot melt adhesive 48 seals one end of the tubular heat-shrinkable tube 47.
[0004]
FIG. 7 shows a state in which a hot-melt adhesive 50 is applied along the inner surface of the heat-shrinkable tube 49 and the heat-welded connection portion 52 of the terminal of the electric wire 51 is inserted into the tube.
[0005]
FIG. 8 shows a set product (assembled product) in which the terminal connection portion of the electric wire 45 is inserted into the heat-shrinkable tube 47 inside the tube heating device 53, and the electric wire 45 is sent in the radial direction by the roller 54, While the tube 47 is heated and shrunk by the heater 55, the hot-melt adhesive 48 and the sealing agent 49 inside the tube are melted and inserted between the electric wires 45 to insulate and waterproof the electric wire connection portion 46. is there.
[0006]
With the tip of the heat-shrinkable tube 49 of FIG. 7 inserted into the cylindrical portion at the tip of a rod-shaped tube holding jig (not shown), the heat-shrinkable tube 49 is heated and shrunk by a tube heating device, and A structure for preventing the hot melt adhesive 50 from flowing out has also been proposed by the present applicant in Japanese Patent Application Laid-Open No. H11-178144.
[0007]
[Problems to be solved by the invention]
However, in the above-described conventional method of sealing the electric wire connection portion and the tube heating device, since the electric wire 45 is conveyed into the heating bath 56 while being sandwiched by the rollers 54, the position of the heat-shrinkable tube 47 is set to the heating bath. There is a concern that the degree of shrinkage of the heat-shrinkable tube 47 and the degree of melting of the hot-melt adhesive 48 and the like in the tube are likely to vary, and the sealing performance of the wire connection portion 46 is deteriorated. Was.
[0008]
In addition, the above-described conventional sealing method and heating device insulate and waterproof only the terminal connecting portion 46 of the electric wire 45, and can insulate and waterproof the intermediate connecting portion where the electric wires are welded and joined in the longitudinal direction. Did not. For this reason, two types of tube heating devices, one for the terminal connection part and one for the intermediate connection part, are required, and there is a problem that the process is enlarged and the equipment cost is high.
[0009]
In view of the above, the present invention can accurately insulate and protect a connection portion of an electric wire without displacement or the like of an electric wire or a heat-shrinkable tube. In addition, a finished product (an assembled product of an electric wire and a tube) can be provided. Provided are a tube heating device and a method for sealing an electric wire connection portion, which can be efficiently recovered, and furthermore, can efficiently insulate and protect any of the terminal connection portion and the intermediate connection portion of the electric wire with one tube heating device. With the goal.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a tube heating device according to claim 1 of the present invention includes a pair of chuck portions for holding the electric wire of an assembled product including a heat-shrinkable tube and an electric wire covering an electric wire connecting portion; It is characterized by comprising a heating tank having an insertion part for inserting the assembled product in the radial direction of the electric wire, and a mechanism for moving the pair of chuck parts forward and backward along the heating tank.
With the above configuration, in the case of an assembled product having an intermediate wire connection portion, the wires extending to both sides of the wire connection portion are gripped by the pair of chuck portions, and the heat shrink tube of the assembled product is heated by the retraction operation of the chuck portion. And is heated at the required temperature for the required time. As a result, the heat-shrinkable tube is contracted and adheres to the outer peripheral surface of the wire connection portion, and the wire connection portion is insulated and protected. When the hot-melt adhesive is loaded in the heat-shrinkable tube, the hot-melt adhesive melts and is filled without gaps between the electric wires or between the tube and the electric wires. The assembled product is taken out of the heating tank by the forward movement of the chuck, and is taken out by opening the chuck while being cooled by air.
[0011]
The tube heating device according to claim 2 is the tube heating device according to claim 1, wherein the product has an inclined portion for picking up the electric wire between the pair of chuck portions, and a product receiving portion following the inclined portion. The collection member is arranged so as to be able to advance and retreat.
With the above-described configuration, the product collection member is lifted while the chuck portion is opened, and the electric wire is lifted at the inclined portion to be released from the chuck portion, and the electric wire is automatically dropped along the inclined portion into the product receiving portion.
[0012]
A tube heating device according to a third aspect is the tube heating device according to the first or second aspect, wherein a tube holding jig can be fixed to one of the pair of chuck portions, and the tube holding jig is heat shrinkable. It is characterized by comprising a cylindrical portion into which the tip of the tube is inserted, a shaft portion located at the center of the chuck following the cylindrical portion, and a chuck fixing portion provided on the shaft portion.
With the above configuration, the shaft portion is located at the center of one chuck, and is located coaxially with the electric wire gripped by the other chuck. The tubular portion is also coaxial with the electric wire, and the heat-shrinkable tube held by the tubular portion is coaxial with the electric wire. Thereby, the radial position of the heat-shrinkable tube is accurately defined. The position of the heat-shrinkable tube in the axial direction can be accurately determined by setting the length of the shaft so that the heat-shrinkable tube is positioned at the center of the pair of chucks when the shaft is fixed to the chuck. Stipulated. Even if the chuck is opened, the tube holding jig does not fall from the chuck, so it is easy to remove the assembly of the electric wire and the tube from the holding jig, and quickly attach the next tube to the holding jig. Can be set.
[0013]
A tube heating device according to a fourth aspect is characterized in that, in the tube heating device according to the third aspect, the chuck fixing portion has an engaging portion that engages with a locking portion on the chuck portion side.
According to the above configuration, the chuck fixing portion can be locked to the chuck portion with one touch, and the attachment and detachment of the tube holding jig is facilitated and quickly performed.
[0014]
According to a fifth aspect of the present invention, there is provided a method of sealing an electric wire connection portion, wherein a pair of chucks grips the electric wires on both sides following an intermediate wire connection portion in the longitudinal direction covered with a heat-shrinkable tube, and the pair of chucks are retracted so that the heat is removed. After allowing the shrink tube to enter the heating tank and heating and shrinking the heat shrink tube, the pair of chucks are advanced to expose the heat shrink tube outside the heating tank and cool down, thereby cooling the heat shrink tube. The chuck is opened to release the electric wire.
With the above configuration, in the case of an assembled product having an intermediate wire connection portion, the wires extending to both sides of the wire connection portion are gripped by the pair of chuck portions, and the heat shrink tube of the assembled product is heated by the retraction operation of the chuck portion. And is heated at the required temperature for the required time. As a result, the heat-shrinkable tube is contracted and adheres to the outer peripheral surface of the wire connection portion, and the wire connection portion is insulated and protected. When the hot-melt adhesive is loaded in the heat-shrinkable tube, the hot-melt adhesive melts and is filled without gaps between the electric wires or between the tube and the electric wires. The assembled product is taken out of the heating tank by the forward movement of the chuck, and is taken out by opening the chuck while being cooled by air.
[0015]
According to a sixth aspect of the present invention, in the method for sealing an electric wire connection part according to the fifth aspect, when the electric wire is gripped by the pair of chucks, the electric wire connection part is marked with a first alignment mark. After the wire is gripped by the pair of chuck portions, the heat-shrinkable tube is moved in the longitudinal direction of the wire to align the wire with the second alignment mark.
According to the above configuration, first, the wire connection portion is accurately positioned between the pair of chuck portions, and then the heat-shrinkable tube is positioned while sliding in the longitudinal direction of the wire to cover the wire connection portion accurately. As a result, the heat-shrinkable tube is arranged at the center of the heating tank, and shrinks accurately without variation.
[0016]
According to a seventh aspect of the present invention, in the method for sealing an electric wire connection portion according to the fifth or sixth aspect, when the pair of chucks are opened, the pair of chucks are lifted by a product collection member while the electric wires are lifted. It is characterized in that the finished product is dropped from the chuck and dropped into the product receiving portion.
With the above configuration, the assembled product is automatically separated from the chuck portion by the product collection member and collected in the product receiving portion.
[0017]
According to a eighth aspect of the present invention, in the method for sealing an electric wire connection portion according to the fifth aspect, a tube holding jig is fixed to one of the pair of chuck portions, and a terminal of the terminal is attached to the tube holding jig. The heat-shrinkable tube for the wire connection portion is held, the wire following the wire connection portion of the terminal is gripped by the other of the pair of chuck portions, and the heat-shrinkable tube for the intermediate wire connection portion is replaced with the heat-shrinkable tube for the middle wire connection portion. The heat-shrinkable tube for the electric wire connection portion is heated in the heating tank.
According to the above configuration, the tube holding jig is fixed to one of the chuck portions, the heat shrinkable tube is held by the tube holding jig, the wire connection portion of the terminal is inserted into the heat shrinkable tube, and the electric wire is connected to the other chuck portion. Is gripped. In this state, the two chuck portions are retracted, the heat-shrinkable tube enters the heating tank and is heated, and after the tubes are contracted and / or the hot melt adhesive in the tubes is melted, the forward movement of the two chuck portions is performed. The assembled product is taken out of the heating tank and cooled. Both chuck parts are opened, the electric wire is released, the holding member remains fixed to the chuck part, and the worker removes the assembled product from the holding member.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 and 2 show one embodiment of a tube heating device according to the present invention (FIG. 1 is a front view, and FIG. 2 is a side view).
[0019]
In the tube heating apparatus 1 shown in FIGS. 1 and 2, reference numeral 2 denotes a heating tank, 3 denotes a control panel, and 4 denotes a set product (assembled product) of an electric wire and a heat-shrinkable tube 14, 15 ( 3 and 4), a pair of left and right slide portions 5 for moving back and forth, 5 is a pair of left and right chuck portions provided on each slide portion 4, and 6 (FIG. 2) is a portion between the chuck portion 5 and the electric wire and the heat-shrinkable tube. It shows a vertically movable product recovery member for forcibly recovering an assembled product (a heat-shrink completed product or product).
[0020]
A heater (not shown) is mounted in the heating tank 2, and a fan 24 is provided on a lower side. A horizontal slit-like insertion portion 18 is provided through the left and right wall portions (side walls) 16 and the front wall portion 17 of the heating tank 2, and a front opening 18 a of the insertion portion 18 is provided in the front wall portion 17. Is located. The slide part 4 is located outside the slit part 18b (outside the heating tank 2) of each side wall 16 communicating with the front opening 18a. The slide portion 4 includes a pair of right and left vertical support portions 19 and a horizontal substrate portion 20 that supports the support portions 19. The substrate portion 20 is slidable, for example, on a horizontal rail (not shown) below the heating tank. Is engaged.
[0021]
The chuck part 5 is fixed to the tip of the support part 19. The center of the chuck portion 5 is located on the same horizontal plane as the center of the front opening 18a and the center of the slit portion 18b. The pair of chuck portions 5 are symmetrically located on the outside of the heating tank 2 so as to face left and right (at the same height without any front-back displacement).
[0022]
The chuck section 5 is constituted by a pair of upper and lower chuck pieces, and can be freely opened and closed in the vertical direction by a pneumatic cylinder 22. A pair of left and right chuck portions 5 grip two places of both ends or a middle part in the longitudinal direction of the plurality of electric wires. The upper and lower chuck pieces 21 constituting the chuck section 5 have a plurality of substantially V-shaped gripping claws 23 as shown in FIG. The upper and lower gripping claws 23 alternately mesh with each other to securely grip the plurality of electric wires 7 and 8.
[0023]
In the embodiment shown in FIG. 3, the electric wires 7 and 8 have a welded connection portion 9 at an intermediate portion in the longitudinal direction. The connection portion 9 is obtained by heat-welding the electrodes (not shown) in the radial direction of the wire in a state where the ends of the plurality of right and left wires 7 and 8 are abutted with each other (accurately, vertically stacked). It is. A flexible heat-shrinkable tube 10 made of synthetic resin is mounted outside the wire connection portion 9. A hot-melt adhesive and / or a sealant (not shown) are loaded inside the heat-shrinkable tube 10. The heat-shrinkable tube 10 is cylindrical and has openings 10a at left and right ends.
[0024]
The electric wire connection part 9 and the heat-shrinkable tube 10 are positioned so as to be located at the center positions of the left and right chuck parts 5. For example, by marking the positioning mark of the electric wire connection portion 9 and the positioning mark of the heat-shrinkable tube 10 on the product recovery member 6 which can be moved up and down on the front side in FIG. The heat shrinkage of No. 10 is performed accurately and without variation. That is, although the temperature tends to be slightly different between the left and right and the center in the heating tank 2, since the heat shrinkable tube 10 is always positioned at the center of the heating tank 2, shrinkage unevenness does not occur for each product.
[0025]
The product recovery member 6 in FIG. 2 is formed by bending a metal plate, includes an upper inclined portion 25, and a product receiving portion 26 that continues below the inclined portion 25. It is fixed to a rod 28a of a vertical air cylinder (drive unit) 28 fixed to a table 27 and can be moved up and down. A pair of inclined portions 25 is provided on the left and right sides, and a hole (not shown) is formed between the pair of inclined portions 25 to allow the heat-shrinkable tube 10 and the electric wires 7 and 8 in the vicinity thereof to escape. A horizontal portion 29 is continued, and an alignment mark for the electric wire connection portion 9 and the heat-shrinkable tube 10 is marked on the horizontal portion 29. The product receiving part 26 is formed in a substantially concave shape by a vertical part 26a following the inclined part 25, a horizontal part (substituted by 26) following the vertical part 26a, and a forward inclined part 26b following the horizontal part.
[0026]
The inclined portion 25 is inclined upward and backward from the front, and the upper end of the inclined portion 25 is located slightly rearward (closer to the heating tank) than the electric wire gripping center of the chuck portion 5. A cylinder 28 is located in front of the heating tank 2, and a cylinder rod 28 a is fixed to an intermediate vertical portion 26 a of the product collection member 6. The shape of the product collection member 6 can be set as appropriate. For example, the inclined portion 25 can be formed in a bar shape instead of a plate shape. The electric wires 7 and 8 (FIG. 3) released from the chuck portion 5 are picked up by the rising inclined portion 25 and dropped into the product receiving portion 26.
[0027]
The control panel 3 in FIG. 1 is provided upright behind the heating tank 2 and includes an operation switch 30, a temperature control unit 31, a heating time setting unit 32, and various display lamps (operation lamps, abnormal lamps, etc.) 33. When the operation switch 30 is turned on, the heater is heated, and when the temperature of the heating tank 2 reaches a predetermined temperature (about 350 ° C.), the lamp 33 indicating that the operation is started is turned on. Hereinafter, a method of sealing the electric wire connection portion 9 will be described.
[0028]
In FIG. 3, an operator holds both electric wires 7, 8 with both hands, positions the electric wire connection portion 9 at the first alignment mark, and depresses a foot switch to cause the right and left chuck portions 5 to grip the electric wires 7, 8. . The heat-shrinkable tube 10 is shifted to the side (the longitudinal direction of the electric wire) of the electric wire connection portion 9 so that the electric wire connection portion 9 can be seen. Next, the heat-shrinkable tube 10 is aligned with the second alignment mark and moved in the longitudinal direction so as to be on the outer periphery of the wire connection portion 9. The wire connection 9 is completely covered with the heat-shrinkable tube 10.
[0029]
Next, the user slides the foot switch to retract the slide portion 4 (FIGS. 1 and 2), and heats the center (the portion where the heat-shrinkable tube 10 is located) of the electric wires 7 and 8 gripped by the chuck portion 5 and the vicinity thereof. It is made to enter the tank 2. After the required time (about 10 seconds) has elapsed, the slide portion 4 automatically advances, and the assembled product 14 of the heat-shrinkable tube 10 and the electric wires 7 and 8 is taken out of the heating tank 2. The heat-shrinkable tube 10 shrinks in the radial direction by heating, and closely adheres to the electric wires 7 and 8 and the connection portions 9 thereof via a hot melt adhesive or the like. The heat-shrinkable tube 10 is naturally cooled for a short period of time by being pulled out while keeping the wires 7 and 8 chucked. The cooling time can be set as appropriate. Forcible cooling by air blow or the like is also possible.
[0030]
While the chuck 5 is automatically opened, the vertical cylinder 28 (FIG. 2) extends, and the inclined portion (inclined surface) 25 of the product collection member 6 moves the electric wires 7 and 8 between the left and right chucks 5 to the center of the chuck. The product (the assembled product of the electric wires 7, 8 and the tube 10) slides down to the product receiving portion 26 along the inclined portion 25 by being raised higher. The operator picks up the product from the product receiving section 26, puts it on a pallet, for example, and carries it to the next process. It is also possible to allow a certain number of assembled products to accumulate in the product receiving portion 26 while allowing them to cool naturally.
[0031]
FIG. 4 shows a configuration example in which the contraction tube 13 is attached to the connection portion 12 of the terminal of the electric wire 11. The same tube heating device 1 as in FIGS. 1 and 2 is used.
[0032]
In FIG. 4, reference numeral 35 denotes a tube holding jig. The tube holding jig 35 is made of metal, and has a hollow cylindrical portion 37 having a larger diameter than the shaft portion 36 concentrically provided at the tip of a solid and straight thin shaft portion 36. Is fixed to one of the right and left chuck portions 5, and the small-diameter portion 13 a at the tip of the heat-shrinkable tube 13 is fitted and held in the tubular portion 37. The shaft portion 36 is fixed to the lower chuck piece 21 by, for example, a fixed plate (fixed portion) 38 and a fixed shaft 39. The form of the heat-shrinkable tube 13 is the same as that of the conventional example shown in FIG.
[0033]
As shown in FIG. 5A and FIG. 5B, one embodiment of the tube holding jig 35 shows a pair of flange-shaped fixing plates (fixing portions) 38 at the rear end of the shaft portion 36 and the intermediate portion in the longitudinal direction. The pair of fixing plates 38 are positioned to face each other, the shaft portion 36 is fixed through the fixing plate 38 near the upper end thereof, and a hemispherical concave portion 40 is formed near the lower end of each inner surface of the fixing plate 38. Each end 39a of the straight fixed shaft 39 is provided to face each other and can be engaged with each recess 40. Both ends 39a of the fixed shaft 39 are formed as hemispherical surfaces. A circular hole 41 is provided inside the cylindrical portion 37, and a guide taper surface is formed at the entrance of the hole 41.
[0034]
In FIG. 4, a horizontal hole 42 (FIG. 3) through which the fixed shaft 39 is inserted through the lower chuck piece 21 is provided, and the fixed shaft 39 is inserted through the hole 42, and each hemispherical end of the fixed shaft 39 is formed. The inner surfaces of the fixed plates 38 (FIG. 5) are slid on the left and right end surfaces of the chuck piece 21 in a state in which the portions (locking portions) 39 a are projected outward from the hole portions 42, so that the center of the chuck portion 5 is located at the center of the chuck. The end portion 39a of the fixed shaft 39 is inserted into and engaged with the concave portion (engaging portion) 40 of the fixed plate 38 while setting the shaft portion 36, whereby the shaft portion 36 is fixed to the chuck piece 21. The shaft portion 36 is gripped by the upper and lower chuck pieces 21 and located at the center of the chuck.
[0035]
It is also possible to provide a ball plunger (locking portion) on the chuck piece 21 instead of the fixed shaft 39 so that the ball biased in the projecting direction by a spring is engaged with the concave portion (engaging portion) 40 of the fixed plate 38. It is. It is also possible to provide a hemispherical or inclined protrusion (locking portion) integrally on the side end surface of the synthetic resin chuck piece 21 and lock the protrusion in the concave portion (engaging portion) 40 of the fixing plate 38. It is.
[0036]
By fixing the tube holding jig 35 to the lower chuck piece 21 by these means, even if the chuck portion 5 is opened, the tube holding jig 35 does not fall and is held at the center of the chuck. That is, the assembled product of the electric wire 11 and the heat-shrinkable tube 13 can be always held at the center of the chuck irrespective of the opening and closing of the chuck portion 5, so that the removal workability is improved and the product is removed from the tube holding jig 35. After removal, the next heat-shrinkable tube 13 can be quickly fitted and set in the tubular portion 37, and the workability of setting the heat-shrinkable tube 13 is improved. Further, since the position of the tubular portion 37 of the tube holding jig 35 is always fixed, there is no need to perform the positioning of the heat-shrinkable tube 13, and the heat-shrinkable tube 13 is fitted to the tubular portion 37. Then, the position of the heat-shrinkable tube 13 is always located at the center of the left and right chuck portions 5, and the heat-shrinkage of the tube 13 is stably performed at the center of the heating tank 2 without variation.
[0037]
Note that, instead of fixing the tube holding jig 35 to the one chuck 5, the shaft 36 of the holding jig 35 is always gripped by the one chuck 5 (one chuck 5 is always closed. It is also possible to open and close only the other chuck portion 5 with a foot switch or the like).
[0038]
Hereinafter, a method of sealing an electric wire connection portion when the assembled product 15 of the electric wire 11 and the tube 13 in the form of FIG. 4 is used will be described step by step.
[0039]
First, the tube holding jig 35 is fixed to one of the chuck portions 5 of the tube heating device 1 in FIG. 2 (preferably the left chuck portion because there are many right-handed operators) in the above-described manner. When the temperature of the heating bath 2 reaches a predetermined temperature, one end 13a of the heat-shrinkable tube 13 is inserted and held in the cylindrical portion 37 on the distal end side of the tube holding jig 35, and the terminal of the electric wire 11 is connected into the tube from the opening 13b of the tube 13. The part 12 is inserted, the two chuck parts 5 are closed, and the electric wire 11 is gripped by the other chuck part 5. The tube holding jig 35 is firmly held and fixed by the other chuck portion 5.
[0040]
Next, both the chuck portions 5 are retracted together with the slide portion 4 by a switch operation or automatically (sequence control or the like), and the heat-shrinkable tube 13 is advanced into the heating tank 2 and heated for a required time. The heating melts the hot-melt adhesive in the heat-shrinkable tube and fills the gaps between the wires 11, and the heat-shrinkable tube 13 shrinks to form a gap on the outer peripheral surface of the wires 11 via the hot-melt adhesive. Adhere without sticking. When the heating is completed, the chuck portions 5 are moved forward together with the assembled product of the electric wire 11 and the tube 13 to open the chuck portion 5 while the assembled product is naturally cooled.
[0041]
An operator removes the product from the tube holding jig 35 by holding the heat-shrinkable tube 13 and stocks the product in a product collection section (not shown). Since the tube holding jig 35 is fixed to one of the chuck portions 5, it does not come off even when the chuck portion 5 is opened, and the next heat-shrinkable tube 13 can be quickly set on the tube holding jig 35. .
[0042]
Since the setting position of the heat-shrinkable tube 13 is determined by fixing the tube holding jig 35 to the chuck portion 5, the operator does not need to visually adjust the position of the heat-shrinkable tube 13, and always accurately heat shrinks. The position of the tube 13 is defined. The positioning of the electric wire connection portion 12 in the tube is performed by abutting the tip of the electric wire connection portion 12 against the inner surface of the bottom of the heat-shrinkable tube 13.
[0043]
In each of the above embodiments, the heat-shrinkable tubes 10 and 13 can be attached to the wire connection portions 9 and 12 only by heat-shrinkage without loading a hot-melt adhesive or the like into the heat-shrinkable tubes. Further, the insertion portion 18 of the heating tank 2 can be provided in a vertical direction so that the assembled product 15 of the electric wire 11 and the heat shrink tube 13 enters the heating tank not vertically but vertically. In this case, the sealed distal end of the heat-shrinkable tube 13 faces downward, and the opening 13b side faces upward.
[0044]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the electric wire is gripped by the pair of chucks, the position of the heat-shrinkable tube is accurately defined without deflection or displacement between the pair of chucks, and heating is performed. A heat-shrinkable tube is placed at the center of the tank, and shrinks accurately without any variation in the heating temperature. Thus, protection such as insulation and waterproofing of the wire connection portion is reliably performed, and reliability of insulation protection is improved.
[0045]
According to the second aspect of the present invention, the assembled product of the electric wire and the heat-shrinkable tube can be automatically collected from the chuck portion by the product collecting member. Is improved.
[0046]
According to the third aspect of the present invention, by selectively using the tube holding jig, the heat-shrinkable tube can be used for both the intermediate connection portion and the terminal connection portion of the electric wire using one tube heating device. Can be adhered. As a result, one heating device, which has conventionally been required two, can be reduced to one, and the installation space and cost of the device can be reduced. Further, since the tube holding jig is fixed to the chuck portion and does not fall even when the chuck portion is opened, the work of attaching and detaching the heat-shrinkable tube to and from the holding jig can be efficiently performed, thereby improving workability. In addition, the heat shrinkability of the tube is enhanced because the shaft of the holding jig is located at the center of the chuck and the heat shrinkable tube is concentric with the electric wire. Is further improved.
[0047]
According to the invention as set forth in claim 4, since the tube holding jig can be easily attached and detached to and from the chuck portion, the setup from the intermediate connection portion to the terminal connection portion can be efficiently performed. Can be.
[0048]
According to the fifth aspect of the present invention, since the electric wire is gripped by the pair of chucks, the position of the heat-shrinkable tube is accurately defined without deflection or displacement between the pair of chucks, and the center position of the heating tank is determined. A heat-shrinkable tube is introduced into the tube, and the shrinkage is always performed accurately without any variation in the heating temperature. Thus, protection such as insulation and waterproofing of the wire connection portion is reliably performed, and reliability of insulation protection is improved.
[0049]
According to the invention as set forth in claim 6, since the position of the wire connection portion with respect to the heating tank and the position of the heat-shrinkable tube can be accurately defined, the heat-shrinkable tube shrinks accurately at the center of the heating tank without variation. In addition, the insulation and protection of the wire connection part are further improved.
[0050]
According to the seventh aspect of the present invention, the assembled product of the electric wire and the heat-shrinkable tube can be automatically collected from the chuck portion by the product collecting member. Is improved.
[0051]
According to the invention as set forth in claim 8, by selectively using the tube holding jig, the heat-shrinkable tube can be used for both the intermediate connection portion and the terminal connection portion of the electric wire using one tube heating device. Can be adhered. As a result, one heating device, which has conventionally been required two, can be reduced to one, and the installation space and cost of the device can be reduced. Further, since the tube holding jig is fixed to the chuck portion and does not fall even when the chuck portion is opened, the work of attaching and detaching the heat-shrinkable tube to and from the holding jig can be efficiently performed, thereby improving workability.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment of a tube heating device according to the present invention.
FIG. 2 is a side view showing the tube heating device.
FIG. 3 is a main part perspective view showing a state where an assembled product having an intermediate connecting portion is gripped by a pair of chucks.
FIG. 4 is a perspective view of an essential part showing a state in which an assembled product having a terminal connection portion is fixed to a chuck via a tube holding jig.
5A and 5B show one embodiment of a tube holding jig, in which FIG. 5A is a side view with a partial cross section, and FIG. 5B is a front view.
FIG. 6 is a cross-sectional view showing an embodiment in which a heat-shrinkable tube is set at a terminal connecting portion of a conventional electric wire.
FIG. 7 is a cross-sectional view showing another embodiment in which a heat-shrinkable tube is set at a terminal connecting portion of the electric wire.
FIG. 8 is a cross-sectional view showing one embodiment of a conventional tube heating device.
[Explanation of symbols]
1 Tube heating device
2 heating tank
4 Slide part (advance / retreat mechanism)
5 Chuck section
6 Product collection materials
7,8,11 Electric wire
9,12 Electric wire connection
10,13 Heat shrink tube
14,15 Assembled product
18 insertion part
25 Inclined part
26 Product receiving section
35 Tube holding jig
36 Shaft
37 tubular part
38 Fixing plate (chuck fixing part)
39a end (locking part)
40 recess (engagement part)

Claims

A pair of chuck portions for gripping the electric wire of an assembled product including a heat-shrinkable tube and an electric wire covering the electric wire connection portion, a heating tank having an insertion portion for inserting the assembled product in a radial direction of the electric wire, A mechanism for moving the chuck portion forward and backward along the heating tank.

The tube according to claim 1, wherein a product collection member having a slope for picking up the electric wire and a product receiving part following the slope is disposed between the pair of chuck portions so as to be able to advance and retreat. Heating equipment.

A tube holding jig can be fixed to one of the pair of chuck portions, and the tube holding jig is located at the center of the chuck following the cylindrical portion into which the tip of the heat-shrinkable tube is inserted, and the cylindrical portion. 3. The tube heating device according to claim 1, wherein the tube heating device comprises a shaft portion to be formed and a chuck fixing portion provided on the shaft portion.

The tube heating device according to claim 3, wherein the chuck fixing portion has an engaging portion that engages with a locking portion on the chuck portion side.

A pair of chucks hold the electric wires on both sides following the wire connecting portion in the longitudinal direction covered with the heat-shrinkable tube, and the pair of chucks are retracted to allow the heat-shrinkable tube to enter the heating tank, and After the tube is heated and shrunk, the pair of chuck portions are advanced to expose the heat shrink tube outside the heating tank and cooled, and the pair of chucks are opened to release the electric wires. How to seal the wire connection.

When gripping the wire with the pair of chucks, align the wire connection portion with a first alignment mark, grip the wire with the pair of chucks, and then move the heat-shrinkable tube in the wire longitudinal direction. 6. The method according to claim 5, wherein the wire is moved to the second alignment mark to be positioned.

7. The electric wire connection part according to claim 5, wherein when the pair of chucks are opened, the electric wire is lifted up by the product collection member, removed from the pair of chucks, and the finished product is dropped into the product receiving part. Sealing method.

A tube holding jig is fixed to one of the pair of chuck portions, the tube holding jig holds a heat-shrinkable tube for a wire connection portion of a terminal, and a wire following the wire connection portion of the terminal is attached to the pair of chucks. The electric wire according to claim 5, characterized in that the other end of the electric wire is gripped and a heat-shrinkable tube for the electric wire connection portion of the terminal is heated by the heating tank in place of the heat-shrinkable tube for the intermediate electric wire connection portion. How to seal the connection.