JP3567593B2

JP3567593B2 - Rare gas discharge lamp

Info

Publication number: JP3567593B2
Application number: JP06667596A
Authority: JP
Inventors: 一浩山本
Original assignee: Ushio Denki KK
Current assignee: Ushio Denki KK
Priority date: 1996-03-22
Filing date: 1996-03-22
Publication date: 2004-09-22
Anticipated expiration: 2016-03-22
Also published as: JPH09259826A

Description

【０００１】
【発明の属する技術分野】
この発明は希ガス放電灯に関し、特にガラスバルブの外周面に一対の帯状の外部電極を配置すると共に、外部電極の端部から端子を導出してなる希ガス放電灯において、端子の外部電極への接続構造の改良に関する。
【０００２】
【従来の技術】
従来のこの種希ガス放電灯は、例えば図１３〜図１５に示すように構成されている。即ち、Ａは例えばガラスバルブよりなる直管状の外囲器であって、その内面には希土類蛍光体，ハロリン酸塩蛍光体などの蛍光体よりなる発光層Ｂが形成されている。尚、外囲器Ａの内部空間には例えば水銀などの金属蒸気を含まないキセノンガスなどを主成分とする希ガスが所定量封入されている。一方、外囲器Ａの外周面には、例えばアルミニウムなどの不透光性の金属部材よりなる帯状の一対の外部電極Ｃ，Ｄが互いに対向するように貼着されており、その外周面は熱収縮性樹脂よりなる保護チュ−ブＥにて被覆・保護されている。又、外部電極Ｃ，Ｄの端部には例えば銅などの端子Ｆ，Ｆが鉛−錫−銀−アンチモンの四元合金よりなるアルミニウム接続用の半田（以下、アルミ半田という）Ｇ，Ｇにて半田付けされている。
【０００３】
この希ガス放電灯は、外部電極Ｃ，Ｄに高周波高電圧（例えば２９ＫＨｚで２５００Ｖｏ−ｐ）を印加することによりキセノンガスの放電が生じ、キセノンガスの励起線によって発光層Ｂが励起されて発光するものであり、光は外部電極Ｃ，Ｄの端部Ｃａ，Ｄａ間の開口部Ｐから放出される。特に、この希ガス放電灯には水銀が用いられていないために、点灯後における光量の立ち上がりが急峻であり、点灯と同時に光量がほぼ１００％近くにまで達するという特徴を有している。このために、近時、ファクシミリ，イメ−ジスキャナ，複写機などのＯＡ機器の原稿読取用の光源として脚光を浴びている。
【０００４】
【発明が解決しようとする課題】
しかしながら、この希ガス放電灯は、次のように製造されるために、最終製品の形態の一定化が難しい上、量産性の改善も難しいという問題がある。
【０００５】
即ち、まず、図１４に示すように、外囲器Ａの外周面に一方の面に接着層を有する外部電極Ｃ，Ｄを、互いに所定の間隔だけ離隔するように、手作業によって貼付ける。そして、外部電極Ｃ，Ｄの端部に端子Ｆ，Ｆをアルミ半田Ｇ，Ｇにて半田付けすると共に、端子Ｆ，Ｆに図示しない外部導出用のハ−ネスを半田付けする。尚、外部電極Ｃ，Ｄの外囲器Ａへの貼着は、外部電極Ｃ，Ｄに端子Ｆ，Ｆを半田付けした後に行なうこともできる。次に、外囲器Ａをシリコ−ンワニス液に浸漬し引き上げた後、例えば１時間程度乾燥させることにより、外囲器Ａ及び外部電極Ｃ，Ｄの表面にはシリコ−ンワニスの被膜が形成される。然る後、図１３及び図１５に示すように、外囲器Ａに熱収縮性樹脂よりなる保護チュ−ブＥを被せると共に、この保護チュ−ブＥを１５０〜２００°Ｃ程度に加熱して熱収縮させ、外囲器Ａの外周面に保護チュ−ブＥを密着させることによって希ガス放電灯が製造される。
【０００６】
このように希ガス放電灯の製造工程には、外部電極Ｃ，Ｄの端部に端子Ｆ，Ｆをアルミ半田Ｇ，Ｇにて半田付けする工程があるが、外部電極Ｃ，Ｄに対する端子Ｆ，Ｆの幅が大きく半田付け面積が広い上に、手作業によって行なわれるために、作業者間のバラツキが大きく、アルミ半田Ｇ，Ｇの盛り上がり形態が一定化しない傾向にある。この傾向は、アルミニウムにて構成した外部電極に対するアルミ半田の濡れ性が十分でないことにも起因しており、アルミ半田Ｇ，Ｇの盛り上がりが大きくなり易い。例えばアルミ半田Ｇ，Ｇが大きく盛り上がってしまうと、端子Ｆ，Ｆの面積が広いために、図１５に示すように、保護チュ−ブＥを装着した状態において、端子Ｆ，Ｆの外部電極Ｃ，Ｄへの半田付け部分の外径が外囲器Ａの中央部分の外径に比べて局部的に大きくなる。
【０００７】
ところで、近時、ファクシミリ，イメ−ジスキャナ，複写機などのＯＡ機器は、ユ−ザ−などの要請に基づいて小形化が進められており、これに組み込まれる原稿読取用光源としての希ガス放電灯に対しても同様に小形化が求められている。従って、組み込み部所における希ガス放電灯とＯＡ機器との間のクリアランスは極めて小さいものである。
【０００８】
このために、希ガス放電灯の外径のバラツキが全長に亘って小さい場合には何ら問題はないものの、上述のように希ガス放電灯の外径が局部的に大きくなると、ＯＡ機器の所定位置に組み込めなくなるという問題が生ずる。
【０００９】
しかも、この希ガス放電灯では、外部電極Ｃ，Ｄの外囲器Ａへの密着性，貼着性及び端子Ｆ，Ｆの外部電極Ｃ，Ｄへの接続強度などの観点から、外部電極Ｃ，Ｄには肉厚の小さいアルミニウムが、端子Ｆ，Ｆには外部電極Ｃ，Ｄの幅の５０％を超える幅の短冊状の銅がそれぞれ使用されている。これらの金属部材は腐食電位列が大きく離れているために、長期間の使用によって双方の接触部分が異種金属接触腐食を起こす。特に、この希ガス放電灯は、使用状態において、それの外部電極Ｃ，Ｄに端子Ｆ，Ｆを介して高周波高電圧が印加されるために、異種金属接触腐食が加速され、ついには、端子Ｆ，Ｆと外部電極Ｃ，Ｄとの電気的な接続関係が断たれてしまい、希ガス放電灯の点灯維持ができなくなるという問題がある。
【００１０】
一方、この希ガス放電灯の製造には、例えば手作業による外部電極Ｃ，Ｄの貼着工程，シリコ−ンワニスの被着−乾燥工程，保護チュ−ブＥの装着−熱収縮工程などのように数多くの製造工程を経なければならないこともあって、量産性を改善し難いという問題もある。
【００１１】
それ故に、本発明の目的は、比較的に簡単な構成によって最終製品の形態のバラツキを小さくでき、生産性を改善できる上、異種金属接触腐食も抑制可能な希ガス放電灯を提供することにある。
【００１２】
【課題を解決するための手段】
従って、本発明は、上述の目的を達成するために、内面に発光層を有する直管状の外囲器と、外囲器の外周面に、それのほぼ全長に亘って離隔して配置した金属部材よりなる帯状の一対の外部電極と、外部電極と電気的な接続関係を有し、かつ外部電極の端部から導出した外部電極とは異なる金属より構成された端子と、外囲器の外周面に、外部電極が被覆されるように装着した透光性の絶縁部材とを具備し、前記端子に切欠き及び／又は孔にて構成された異形部を形成すると共に、前記外部電極の幅Ｗと端子の実質的な幅ｄとを０．１Ｗ≦ｄ≦０．５Ｗの関係に設定し、この端子と外部電極とを導電性接着剤にて電気的に接続したものであり、本発明の第２の発明は、前記透光性の絶縁部材を、透光性シ−ト又は熱収縮性樹脂よりなる保護チュ−ブにて構成したことを特徴とする。
【００１３】
又、本発明の第３の発明は、内面に発光層を有する直管状の外囲器と、外囲器の全長とほぼ同程度の長さを有する透光性シ−トの一方の面に金属部材よりなる帯状の一対の外部電極を互いに離隔して配置し、かつ外部電極の端部に外部電極とは異なる金属より構成された異形部を有する端子を導電性接着剤にて電気的機械的に接続してなるシ−ト構体とを具備し、前記外部電極の幅Ｗと端子の実質的な幅ｄとを０．１Ｗ≦ｄ≦０．５Ｗの関係に設定すると共に、前記端子の異形部を切欠き及び／又は孔にて構成し、前記外囲器の外周面にシ−ト構体を、外囲器と透光性シ−トとの間に外部電極が位置するように巻回・密着したことを特徴とする。
【００１４】
【発明の実施の形態】
次に、本発明の第１の実施例について図１〜図５を参照して説明する。同図において、１は例えばガラスバルブにて密閉状に構成された直管状の外囲器であって、その内面には希土類蛍光体，ハロリン酸塩蛍光体などの蛍光体よりなる発光層２が形成されている。特に、外囲器１の封着構造はガラスバルブの端部にディスク状の封着ガラス板１ａ，１ｂを封着して構成されているが、例えば単にガラスバルブを加熱しながら縮径加工し溶断して構成することもできる。尚、この外囲器１の密閉空間には水銀などの金属蒸気を含まない例えばキセノン（Ｘｅ），クリプトン（Ｋｒ），ネオン（Ｎｅ），ヘリウム（Ｈｅ）などの希ガスが単一又は混合して所定量封入されているが、キセノンを主成分とする希ガスを例えば２０〜１１０Ｔｏｒｒの圧力で封入することが望ましい。
【００１５】
この外囲器１の外周面にはシ−ト構体３が密着するように巻回されている。このシ−ト構体３は、例えば外囲器１の全長とほぼ同程度の長さを有し、かつ厚さが２０〜１００μｍの範囲に設定された透光性シ−ト４と、この透光性シ−ト４の一方の面に互いに所定の間隔だけ離隔配置して接着された不透光性の金属部材よりなる帯状の一対の外部電極５，６と、この外部電極５，６の端部から、一方の端部に複数の孔よりなる異形部５１Ａ，６１Ａを有し、かつ他方の端部が透光性シ−ト４の端縁部分より突出するように導出された端子５１，６１と、外部電極５，６と端子５１，６１とを電気的機械的に接続する導電性接着剤５２，６２と、透光性シ−ト４の一方の面に付与された粘着ないし接着機能を有する接着層９とから構成されている。
【００１６】
特に、このシ−ト構体３において、導電性接着剤５２，６２は樹脂系接着剤に導電性粉末を所定量分散させて構成されており、例えばアクリル系接着剤にニッケル粉末を分散させたものが好適するが、樹脂系接着剤としてはアクリル系の他、シリコ−ン系，エポキシ系，ビニル系などが、導電性粉末としてはニッケルの他、カ−ボン，銅，銀などの部材をそれぞれ適宜に組み合わせて使用することもできる。特に、外部電極５，６と端子５１，６１とを導電性接着剤５２，６２にて接続する際に、導電性接着剤５２，６２は端子５１，６１の異形部５１Ａ，６１Ａにも充実される。又、接着層９としてはシリコ−ン系接着剤が好適するが、アクリル系接着剤なども使用できる。この接着層９は外部電極５，６の露出面にも形成されているが、予め透光性シ−ト４の一方の面にのみ形成して外部電極５，６の露出面には形成しないように構成することもできる。さらに、透光性シ−ト４としては、例えばポリエチレンテレフタレ−ト（ＰＥＴ）樹脂が好適するが、ポリエステル樹脂なども利用できる。
【００１７】
又、外部電極５，６及び端子５１，６１は、腐食電位列が離れた位置にある金属部材にて構成されており、例えば外部電極５，６としては帯状のアルミニウム箔が、端子５１，６１としては短冊状の銅が好適する。しかしながら、外部電極５，６としては導電性に優れ、かつ不透光性の金属部材であればアルミニウムの他に、ニッケルなどの金属部材も利用できるし、端子５１，６１としては銅の他に、銀，ステンレス，銅−ニッケル合金などの金属部材も利用できる。特に、外部電極５，６の幅Ｗと端子５１，６１の幅ｄとは、０．１Ｗ≦ｄ≦０．５Ｗなる関係に設定されている。特に、端子５１，６１の肉厚は０．１〜０．５ｍｍの範囲が望ましい。
【００１８】
上述のシ−ト構体３は外囲器１の外周面に、外部電極５，６が外囲器１と透光性シ−ト４との間に位置するように装着されており、後述の第２の開口部（８）において、透光性シ−ト４の一方の端部４ａに他方の端部４ｂを重ね合わせた上で接着されている。特に、シ−ト構体３の外囲器１への装着状態において、外部電極５，６の一端５ａ，６ａの間には第１の開口部７が、外部電極５，６の他端５ｂ，６ｂの間には第２の開口部８がそれぞれ形成されており、発光層２からの光は主として第１の開口部７から放出される。尚、第１，第２の開口部７，８の開口角θ_１，θ_２はθ_１＞θ_２の関係に設定することが望ましいが、同一に設定することもできる。
【００１９】
この希ガス放電灯は、例えば次のように製造される。まず、図６（ａ）に示すように、外部電極５，６の端部に端子５１，６１の異形部５１Ａ，６１Ａを重ね合わせる。次に、同図（ｂ）に示すように、外部電極５，６と端子５１，６１との重なり部分及びその周辺に導電性接着剤５２，６２を、異形部５１Ａ，６１Ａにも充実されるように被着し、固化させる。これにより、外部電極５，６と端子５１，６１とは電気的機械的に接続される。次に、同図（ｃ）に示すように、透光性シ−ト４の一方の面に外部電極５，６を、導電性接着剤５２，６２の被着側が透光性シ−ト側となり、しかも、端子５１，６１の他方の端部が透光性シ−ト４の端縁部分より突出するように離隔して配置し、接着する。然る後、透光性シ−ト４の一方の面及び外部電極５，６の露出面に接着層９を形成してシ−ト構体３が完成する。尚、予め、外部電極５，６の露出面に接着層を形成しておけば、外部電極の貼着後における接着層の形成工程は省略できる。
【００２０】
次に、図７に示すように、シ−ト構体３を展開した状態で所定の部位例えば組み立てステ−ジに載置する。次に、外囲器１をシ−ト構体３の透光性シ−ト４の一端４ａに、外囲器１の長手方向が外部電極５，６の長手方向に沿うように（平行となるように）位置させる。この状態で、外囲器１を透光性シ−ト４に若干押しつけるようにして図示矢印方向（透光性シ−ト４の他端４ｂの方向）に転動させる。これによって、シ−ト構体３は、図１に示すように、外囲器１の外周面に巻回される上、透光性シ−ト４の一端４ａに他端４ｂが重ね合わされ、接着層９によって接着される。尚、接着層９に熱硬化性接着剤を使用する場合には、熱処理することが望ましい。
【００２１】
この希ガス放電灯によれば、端子５１，６１の一方の端部は外部電極５，６の端部に重なり合うように配置した上で導電性接着剤５２，６２にて電気的機械的に接続されているが、被着状態では導電性接着剤５２，６２がペ−スト状であるために、熟練を要するまでもなく、その厚みを十分に小さくできる。このために、シ−ト構体３を外囲器１の外周面に巻回・密着させた状態において、放電灯の外径は全長に亘ってほぼ均斉化され、外囲器端部で局部的に外径が大きくなるということはなくなる。従って、ＯＡ機器において、希ガス放電灯の組み込み空間部がかなり制約された状態であっても、確実に組み込むことができる。
【００２２】
その上に、端子５１，６１の一方の端部には、例えば複数の孔よりなる異形部５１Ａ，６１Ａが形成されており、その異形部５１Ａ，６１Ａに導電性接着剤５２，６２が充実されるように被着されている。このために、固化状態において、端子５１，６１にそれの導出方向への引張力が作用しても、異形部５１Ａ，６１Ａと導電性接着剤５２，６２との喰い付きによって端子５１，６１が脱却されることはなくなる。従って、組み立て作業において、端子５１，６１に不所望の力が作用しないように細心の注意を払う必要がないために、作業能率を著しく高めることができる。
【００２３】
特に、外部電極５，６の幅Ｗと端子５１，６１の幅ｄとの関係を０．１Ｗ≦ｄ≦０．５Ｗに設定すれば、外部電極５，６と端子５１，６１とを直に接触させた上で導電性接着剤５２，６２を利用して接続しても、異種金属接触腐食の発生を抑制できる。従って、長期間に亘って安定した動作状態を維持できる。しかしながら、端子５１，６１の幅ｄが０．１Ｗ未満になると、端子自身の機械的な強度が低下するし、異形部の形成も困難になる。逆に、それの幅ｄが０．５Ｗを超えると、シ−ト構体３を外囲器１に巻回する際に、端子５１，６１を外囲器１の外周面に倣い易くするために、予め、外囲器１の外周面に倣う曲面に加工しなければならず、その加工が極めて面倒になるという問題が生ずる。従って、両者は上述の関係に設定することが望ましい。
【００２４】
一方、上述の製造方法によれば、外囲器１をシ−ト構体３の上で単に転動させるだけで、外部電極５，６を外囲器１の外周面に貼着できるし、外部電極５，６は透光性シ−ト４に予め所定の間隔で配列されているために、貼り付けの際に外部電極５，６の間隔を所定の間隔となるように調整する必要が全くなく、仮に手作業であっても作業能率を著しく向上できる。具体的には、従来方法では製造に６０分間を要していたものが、本発明方法によれば１分程度に短縮できる。
【００２５】
又、シ−ト構体３における透光性シ−ト４の一方の面には、接着層９が形成されているために、外囲器１をシ−ト構体３の上で転動させるだけの単純動作によって、シ−ト構体３を外囲器１の外周面に巻回し密着させることができる。従って、作業能率を飛躍的に改善できるのみならず、機械化が可能となり、一層の量産効果が期待できる。
【００２６】
しかも、シ−ト構体３の外囲器１の外周面への巻回・密着状態において、透光性シ−ト４の端部４ａ，４ｂは互いに重ね合わせて接着されているために、外部電極５，６の被覆信頼性を高めることができる。特に、透光性シ−ト４の厚さを２０〜１００μｍの範囲に設定すれば、端部４ａ，４ｂの安定した重合・接着性が得られる。しかしながら、その厚さが２０μｍ未満になると、十分の絶縁性を確保できなくなるし、逆に１００μｍを超えると、シ−トの腰が強くなって端部４ａ，４ｂの重ね合わせ部分が剥がれ易くなり、巻回作業も面倒になる。従って、シ−ト厚さは上記範囲に設定することが望ましい。
【００２７】
又、外部電極５，６は、シ−ト構体３を外囲器１に装着する際に、透光性シ−ト４と外囲器１の外周面との間に位置するように配慮されているために、ファクシミリなどのＯＡ機器に適用されて使用時に高電圧が印加されても、外部電極間は勿論のこと、対地間絶縁をも十分に確保することができる。
【００２８】
図８は本発明にかかる端子５１（６１）のそれぞれ異なった実施例を示すものであって、同図（ａ）の端子５１は一方の端部の両側における同一部分に半円状の切欠きよりなる異形部５１Ａを形成して構成されている。尚、他方の端部は一方の端部より幅広に形成し、ハ−ネスなどの接続が容易になるように配慮されている。同図（ｂ）の端子５１は一方の端部に同図（ａ）に示す異形部５１Ａを互い違い状に形成して構成されている。さらに、同図（ｃ）の端子５１は一方の端部の中央部分に切欠き（切り込み）よりなる異形部５１Ａを形成して二股状に構成されている。これらの異形部５１Ａは互いに組み合わせたり、或いは図３に示す孔よりなる異形部５１Ａと適宜に組み合わせて使用することもできる。
【００２９】
図９〜図１０は本発明の第２の実施例を示すものであって、基本的な構成は図１〜図５に示す希ガス放電灯と同じである。異なる点は、第１の開口部７に対応する外囲器１の内面部分に発光層２を形成しないアパ−チャ部（光放出部）２ａを形成したこと、外部電極５（６）と端子５１（６１）とを接続する導電性接着剤５２（６２）を外囲器１の外周面側に配置したことである。尚、アパ−チャ部２ａの開口角は例えば７０〜１１０度の範囲に設定されているが、用途，目的などに応じて適宜に変更できる。
【００３０】
この実施例によれば、端子５１の外部電極５への接続は、透光性シ−ト４に配置された外部電極５の端部に端子５１を重ね合わせた後に、導電性接着剤５２の被着・固化によって行うことができるために、組み立て作業をさらに改善することができる。
【００３１】
又、発光層２から放射された光は外囲器内において高密度化されてアパ−チャ部２ａから第１の開口部７を経て外部に放出されるために、原稿照射装置に適用した場合、原稿面の照度を高めることができ、原稿の読み取り精度を高めることができる。
【００３２】
特に、外部電極５，６の外囲器側の面に光反射性を付与すれば、アパ−チャ部２ａの照度をさらに高めることができ、原稿の読み取り精度も一層改善できる。これの材料としては、例えばアルミニウム箔のように光反射性を有する金属部材が好適する。
【００３３】
図１１は本発明の第３の実施例を示すものであって、基本的な構成は図９〜図１０に示す希ガス放電灯と同じである。異なる点は、シ−ト構体３の外囲器１への巻回・密着状態において、透光性シ−ト４のそれぞれの端部４ａ，４ｂの主たる重ね合わせ部分を外部電極５の外面側に設定したことである。尚、この重ね合わせ部分は外部電極５の外面側とすることもできる。
【００３４】
図１２は本発明の第４の実施例を示すものであって、基本的な構成は図１〜図５に示す希ガス放電灯と同じである。異なる点は、シ−ト構体３の外周面に熱収縮性樹脂よりなる保護チュ−ブ１０を被せたことである。尚、この保護チュ−ブ１０は外囲器１に装着した後、例えば１５０〜２００°Ｃ程度に加熱し、収縮させることによりシ−ト構体３に密着される。
【００３５】
この実施例によれば、希ガス放電灯の適用部所における環境条件が厳しい，安全基準が高いなどの場合には、例えば耐熱性などに優れ、かつ透光性を有する保護チュ−ブ１０にてシ−ト構体３を被覆することによって、より高品位の製品を提供できる。
【００３６】
特に、この実施例の構造は、図９，図１１に示す第２，第３の実施例にも適用することができる。
【００３７】
図９，図１１に示す第２，第３の実施例を利用して本発明の第５の実施例について説明する。この実施例は、外囲器１の外周面に一対の外部電極５，６を貼着した後、透光性シ−ト４を外囲器１の外周面に、外部電極５，６が被覆されるように巻回・密着させると共に、透光性シ−ト４のそれぞれの端部４ａ，４ｂを重ね合わせて接着するものである。尚、端子は、外部電極の外囲器への貼着に先立って、外部電極に導電性接着剤によって接続しておいてもよいし、或いは外囲器への貼着後に、接続してもよい。
【００３８】
この実施例によれば、上述の各実施例に比較すると、機械化，作業能率の点で劣るものの、従来例よりは改善できる。特に、透光性シ−ト４の巻回に先立って、予め、外囲器１の外周面にシリコ−ンワニスなどの絶縁被膜を形成しておけば、絶縁性の一層の改善が可能となる。
【００３９】
尚、本発明は、何ら上記実施例にのみ制約されることなく、例えばシ−ト構体における外部電極は所定形状に形成されたものを貼り付ける他、蒸着，溶射などによって形成することもできる。外囲器の外周面へのシ−ト構体の貼着は、外囲器をシ−ト構体の上で転動させる他、シ−ト構体を回転させて貼着することもできるし、それぞれの動作を併用させることもできる。又、シ−ト構体のそれぞれの端部は重ね合わせる他、突き合わせたり，若干隙間が形成されるように処理することもできる。さらに、外部電極と端子との幅は、異種金属接触腐食を問題にしない場合には、上述の関係以外に設定することもできる。
【００４０】
【実施例】
次に、実験例について説明する。外径が８ｍｍ，長さが３００ｍｍの鉛ガラスよりなる外囲器に図４に示すシ−ト構体を巻回・密着させる。このシ−ト構体における外部電極には肉厚が７０μｍ，幅Ｗが８ｍｍの帯状のアルミニウムを用い、端子には肉厚が０．１５ｍｍ，幅ｄが２ｍｍの短冊状の銅を用い、かつ一方の端部の両側に半径が０．５ｍｍの半円形の異形部をそれぞれ３個形成し、両者は（株）スリ−ボンド製の二液性常温硬化型接着剤３３８１（ニッケル粉末を含むアクリル系導電性接着剤）で電気的機械的に接続されている。この希ガス放電灯を周囲温度が６０°Ｃ，相対湿度が９０％の雰囲気に配置し、外部電極に２７ＫＨｚ，２０００Ｖｏ−ｐの高周波高電圧を端子を介して印加する加速試験を行なったところ、１５００時間を経過するも、外部電極と端子との接続部分に腐食は全く認められなかった。しかしながら、端子の幅ｄを４．５ｍｍに設定し、外部電極と端子とを鉛（５９％）−錫（４０％）−銀（０．５％）−アンチモン（０．５％）よりなるアルミ半田で接続した以外は本発明品と同一構成の従来品では、７００時間を経過した段階で腐食が進行し始めていることが認められた。
【００４１】
これは、本発明品において、腐食電位の高い銅の端子の幅ｄが腐食電位の低いアルミニウムの外部電極の幅Ｗに対してほぼ０．２５と十分に狭くなっているために、腐食の進行が抑制されたものと推測される。しかしながら、従来品では、０．５６であり、この状態で腐食の進行が認められたことから、端子の幅ｄと外部電極の幅Ｗとの関係はｄ＝０．１Ｗ〜０．５Ｗに設定することが望ましい。
【００４２】
又、本発明品では、外径のバラツキ（最大値−最小値）が０．４２ｍｍであったのに対し、従来品ではバラツキが２．６ｍｍであった。このために、本発明品では、小形化されたＯＡ機器への組み込みに何の支障も生じなかったが、従来品では組み込みに支障の生ずるものが発生した。これは、本発明品における端子が外部電極の切欠き内に配置されているためと推測される。
【００４３】
さらに、本発明品は、１５００時間経過後に端子に２Ｋｇの引張力を作用させても、端子が外部電極から脱却されることはなかった。
【００４４】
【発明の効果】
以上のように本発明によれば、端子の一方の端部は外部電極の端部に重なり合うように配置した上で導電性接着剤にて電気的機械的に接続されているが、被着状態では導電性接着剤がペ−スト状であるために、熟練を要するまでもなく、その厚みを十分に小さくできる。このために、シ−ト構体を外囲器の外周面に巻回・密着させた状態において、放電灯の外径は全長に亘ってほぼ均斉化され、外囲器端部で局部的に外径が大きくなるということはなくなる。従って、ＯＡ機器において、希ガス放電灯の組み込み空間部がかなり制約された状態であっても、確実に組み込むことができる。
【００４５】
しかも、端子の一方の端部には、切欠き及び／又は孔よりなる異形部が形成されており、その異形部に導電性接着剤が充実されるように被着されている。このために、固化状態において、端子にそれの導出方向への引張力が作用しても、異形部と導電性接着剤との喰い付きによって端子の抜け外れを効果的に抑制できる。従って、組み立て作業において、端子に不所望の力が作用しないように細心の注意を払う必要がないために、作業能率を著しく高めることができる。
【００４６】
特に、外部電極の幅Ｗと端子の幅ｄとの関係を０．１Ｗ≦ｄ≦０．５Ｗに設定すれば、外部電極と端子とを直に接触させた上で導電性接着剤を利用して接続しても、異種金属接触腐食の発生を抑制できる。従って、長期間に亘って安定した動作状態を維持できる。
【００４７】
又、シ−ト構体を用いる場合には、外囲器をシ−ト構体の上で単に転動させるだけで、外部電極を外囲器の外周面に貼着できるし、外部電極は透光性シ−トに予め所定の間隔で配列されているために、貼り付けの際に外部電極の間隔を所定の間隔となるように調整する必要が全くない。従って、作業能率を飛躍的に改善できるのみならず、機械化が可能となり、一層の量産効果が期待できる。
【００４８】
さらに、外部電極は、シ−ト構体を外囲器に装着する際に、透光性シ−トと外囲器の外周面との間に位置するように配慮されているために、ファクシミリなどのＯＡ機器に適用されて使用時に高電圧が印加されても、外部電極間は勿論のこと、対地間絶縁をも十分に確保することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施例を示す縦断面図。
【図２】図１のＸ−Ｘ断面図。
【図３】図１の一部破断状態の側面図。
【図４】本発明にかかるシ−ト構体の展開図。
【図５】図４のＹ−Ｙ断面図。
【図６】本発明にかかるシ−ト構体の組み立て方法を説明するための平面図であって、同図（ａ）は外部電極の端部に端子を配置した状態を示し、同図（ｂ）は端子と外部電極とを導電性接着剤にて接続した状態を示し、同図（ｃ）は透光性シ−トの所定位置に外部電極を配置した状態を示す。
【図７】本発明方法を説明するための縦断面図。
【図８】本発明にかかる端子の異なった実施例を示す平面図であって、同図（ａ）は対照的に切欠き状の異形部を形成した端子を示し、同図（ｂ）は切欠き状の異形部を互い違い状に形成した端子を示し、同図（ｃ）はスリット状の切欠きよりなる異形部を形成し、端部を二股状に構成した端子を示す。
【図９】本発明の第２の実施例を示す縦断面図。
【図１０】図９の要部断面図。
【図１１】本発明の第３の実施例を示す縦断面図。
【図１２】本発明の第４の実施例を示す縦断面図。
【図１３】従来例の縦断面図。
【図１４】従来方法を説明するための斜視図。
【図１５】図１３のＺ−Ｚ断面図。
【符号の説明】
Ｗ外部電極の幅
ｄ端子の幅
１外囲器
２発光層
２ａアパ−チャ部
３シ−ト構体
４透光性シ−ト
５，６外部電極
５１，６１端子
５１Ａ，６１Ａ異形部
５２，６２導電性接着剤
７第１の開口部
８第２の開口部
９接着層
１０保護チュ−ブ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rare gas discharge lamp, and particularly to a rare gas discharge lamp in which a pair of strip-shaped external electrodes are arranged on the outer peripheral surface of a glass bulb and a terminal is led out from an end of the external electrode. And improvement of the connection structure.
[0002]
[Prior art]
A conventional rare gas discharge lamp of this type is configured as shown in, for example, FIGS. That is, A is a straight tubular envelope made of, for example, a glass bulb, and a light emitting layer B made of a phosphor such as a rare earth phosphor or a halophosphate phosphor is formed on the inner surface thereof. A predetermined amount of a rare gas mainly containing xenon gas or the like that does not contain a metal vapor such as mercury is sealed in the inner space of the envelope A. On the other hand, a pair of strip-shaped external electrodes C and D made of a non-translucent metal member such as aluminum are attached to the outer peripheral surface of the envelope A so as to face each other. Covered and protected by a protective tube E made of a heat-shrinkable resin. At the ends of the external electrodes C and D, terminals F and F made of, for example, copper are connected to solders (hereinafter referred to as aluminum solder) G and G for aluminum connection made of a quaternary alloy of lead-tin-silver-antimony. Soldered.
[0003]
In this rare gas discharge lamp, when a high frequency high voltage (for example, 2500 Vop at 29 KHz) is applied to the external electrodes C and D, discharge of xenon gas occurs, and the light emitting layer B is excited by the xenon gas excitation line to emit light. The light is emitted from the opening P between the ends Ca and Da of the external electrodes C and D. In particular, since no mercury is used in this rare gas discharge lamp, the light quantity rises sharply after lighting, and the quantity of light reaches almost 100% simultaneously with lighting. For this reason, recently, it has been spotlighted as a light source for reading originals of OA equipment such as a facsimile, an image scanner, and a copying machine.
[0004]
[Problems to be solved by the invention]
However, since this rare gas discharge lamp is manufactured as follows, it is difficult to stabilize the form of the final product, and it is also difficult to improve mass productivity.
[0005]
That is, first, as shown in FIG. 14, external electrodes C and D having an adhesive layer on one surface are manually attached to the outer peripheral surface of the envelope A so as to be separated from each other by a predetermined distance. Then, the terminals F, F are soldered to the ends of the external electrodes C, D with aluminum solders G, G, and an external lead-out harness (not shown) is soldered to the terminals F, F. The external electrodes C, D can be attached to the envelope A after the terminals F, F are soldered to the external electrodes C, D. Next, the envelope A is immersed in a silicone varnish solution, pulled up, and then dried, for example, for about one hour, so that a silicone varnish coating is formed on the surfaces of the envelope A and the external electrodes C and D. You. Thereafter, as shown in FIGS. 13 and 15, the envelope A is covered with a protective tube E made of a heat-shrinkable resin, and the protective tube E is heated to about 150 to 200 ° C. Then, the protective tube E is brought into close contact with the outer peripheral surface of the envelope A to produce a rare gas discharge lamp.
[0006]
As described above, the manufacturing process of the rare gas discharge lamp includes a process of soldering the terminals F, F to the ends of the external electrodes C, D with the aluminum solders G, G. , F are large, the soldering area is large, and since the soldering is performed manually, there is a large variation between workers, and there is a tendency that the swelling form of the aluminum solders G, G is not constant. This tendency is due to insufficient wettability of the aluminum solder to the external electrode made of aluminum, and the swelling of the aluminum solder G tends to be large. For example, if the aluminum solders G, G rise greatly, the area of the terminals F, F is large, so that the external electrodes C of the terminals F, F in a state where the protection tube E is mounted as shown in FIG. , D is locally larger than the outer diameter of the central portion of the envelope A.
[0007]
Recently, OA equipment such as a facsimile, an image scanner, and a copying machine has been reduced in size in response to a request from a user or the like, and a rare gas discharge as a light source for document reading incorporated in the OA equipment has been advanced. Similarly, miniaturization is required for electric lights. Therefore, the clearance between the rare gas discharge lamp and the OA equipment at the installation part is extremely small.
[0008]
For this reason, there is no problem if the variation in the outer diameter of the rare gas discharge lamp is small over the entire length, but when the outer diameter of the rare gas discharge lamp is locally increased as described above, the predetermined size of the OA equipment is reduced. A problem arises in that it cannot be installed in a position.
[0009]
In addition, in the rare gas discharge lamp, the external electrodes C and D are taken into consideration from the viewpoints of the adhesion and the adhesion of the external electrodes C and D to the envelope A, the connection strength of the terminals F and F to the external electrodes C and D, and the like. , D are made of aluminum having a small thickness, and the terminals F, F are made of strip copper having a width exceeding 50% of the width of the external electrodes C, D. Since the corrosion potential trains of these metal members are far apart from each other, the contact portions of the two members cause dissimilar metal contact corrosion due to long-term use. Particularly, in this rare gas discharge lamp, in use, a high-frequency high voltage is applied to the external electrodes C and D via the terminals F and F, so that dissimilar metal contact corrosion is accelerated. There is a problem in that the electrical connection between F, F and the external electrodes C, D is broken, and it becomes impossible to maintain the lighting of the rare gas discharge lamp.
[0010]
On the other hand, the manufacture of the rare gas discharge lamp includes, for example, a process of manually attaching the external electrodes C and D, a process of applying and drying a silicone varnish, and a process of installing a protective tube E and a heat shrinking process. In addition, there is a problem that it is difficult to improve the mass productivity, because it has to go through many manufacturing steps.
[0011]
Therefore, an object of the present invention is to provide a rare gas discharge lamp that can reduce variation in the form of the final product with a relatively simple configuration, can improve productivity, and can suppress the contact corrosion of dissimilar metals. is there.
[0012]
[Means for Solving the Problems]
Therefore, in order to achieve the above object, the present invention provides a straight tubular envelope having a light-emitting layer on the inner surface, and a metal disposed on the outer peripheral surface of the envelope over substantially the entire length thereof. A pair of band-shaped external electrodes made of a member, a terminal having an electrical connection with the external electrode, and a terminal formed of a metal different from the external electrode derived from an end of the external electrode, and an outer periphery of the envelope A light-transmissive insulating member mounted on the surface so as to cover the external electrode, forming a deformed portion formed of a notch and / or a hole in the terminal, and a width of the external electrode. The present invention is characterized in that W and the substantial width d of the terminal are set in a relationship of 0.1 W ≦ d ≦ 0.5 W, and the terminal and the external electrode are electrically connected by a conductive adhesive. According to a second aspect of the present invention, the transparent insulating member is protected by a transparent sheet or a heat-shrinkable resin. Interview - characterized by being constituted by blanking.
[0013]
The third invention of the present invention is directed to a straight tubular envelope having a light-emitting layer on the inner surface and a translucent sheet having a length substantially equal to the entire length of the envelope. A pair of strip-shaped external electrodes made of a metal member are spaced apart from each other, and a terminal having a deformed portion made of a metal different from the external electrode at an end of the external electrode is electrically mechanically connected with a conductive adhesive. And a width W of the external electrode and a substantial width d of the terminal are set in a relationship of 0.1 W ≦ d ≦ 0.5 W, and the width of the terminal is set to 0.1 W ≦ d ≦ 0.5 W. The deformed portion is constituted by notches and / or holes, and a sheet structure is wound around the outer peripheral surface of the envelope so that an external electrode is located between the envelope and the translucent sheet. It is characterized by having times and close contact.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a first embodiment of the present invention will be described with reference to FIGS. In the figure, reference numeral 1 denotes a straight tubular envelope which is hermetically constituted by a glass bulb, for example, and a light emitting layer 2 made of a phosphor such as a rare earth phosphor or a halophosphate phosphor is provided on the inner surface thereof. Is formed. In particular, the sealing structure of the envelope 1 is configured by sealing the disk-shaped sealing glass plates 1a and 1b to the ends of the glass bulb. It can also be configured by fusing. In the enclosed space of the envelope 1, a rare gas such as xenon (Xe), krypton (Kr), neon (Ne), or helium (He) which does not contain metal vapor such as mercury is used alone or mixed. However, it is preferable to fill a rare gas containing xenon as a main component at a pressure of, for example, 20 to 110 Torr.
[0015]
A sheet structure 3 is wound around the outer peripheral surface of the envelope 1 so as to be in close contact therewith. The sheet structure 3 has, for example, a length substantially equal to the entire length of the envelope 1 and a thickness of 20 to 100 μm. A pair of strip-like external electrodes 5 and 6 made of a light-transmissive metal member adhered to one surface of the light sheet 4 at a predetermined distance from each other and bonded to each other; From the end, a terminal 51 is provided which has deformed portions 51A and 61A formed of a plurality of holes at one end, and is drawn out such that the other end protrudes from an edge portion of the translucent sheet 4. , 61, conductive adhesives 52, 62 for electrically and mechanically connecting the external electrodes 5, 6 to the terminals 51, 61, and an adhesive or adhesive applied to one surface of the translucent sheet 4. And an adhesive layer 9 having a function.
[0016]
In particular, in the sheet structure 3, the conductive adhesives 52 and 62 are formed by dispersing a predetermined amount of conductive powder in a resin-based adhesive. For example, the conductive adhesives 52 and 62 are obtained by dispersing nickel powder in an acrylic adhesive. It is preferable to use resin-based adhesives such as silicone-based, epoxy-based, and vinyl-based materials in addition to acrylic-based adhesives, and to use conductive powder such as nickel, carbon, copper, and silver members. They can be used in appropriate combinations. In particular, when the external electrodes 5 and 6 are connected to the terminals 51 and 61 by the conductive adhesives 52 and 62, the conductive adhesives 52 and 62 are also enhanced in the deformed portions 51A and 61A of the terminals 51 and 61. You. As the adhesive layer 9, a silicone-based adhesive is suitable, but an acrylic-based adhesive can also be used. Although this adhesive layer 9 is also formed on the exposed surfaces of the external electrodes 5 and 6, it is formed only on one surface of the translucent sheet 4 in advance and is not formed on the exposed surfaces of the external electrodes 5 and 6. It can also be configured as follows. Further, as the translucent sheet 4, for example, polyethylene terephthalate (PET) resin is preferable, but polyester resin or the like can also be used.
[0017]
The external electrodes 5 and 6 and the terminals 51 and 61 are made of a metal member at a position away from the corrosion potential train. For example, the external electrodes 5 and 6 are formed of strip-shaped aluminum foil. As such, strip-shaped copper is preferable. However, as the external electrodes 5 and 6, a metal member such as nickel or the like other than aluminum can be used as long as it is a metal member that is excellent in conductivity and is opaque. Also, metal members such as silver, stainless steel, and copper-nickel alloy can be used. In particular, the width W of the external electrodes 5 and 6 and the width d of the terminals 51 and 61 are set such that 0.1 W ≦ d ≦ 0.5 W. In particular, the thickness of the terminals 51 and 61 is preferably in the range of 0.1 to 0.5 mm.
[0018]
The above-mentioned sheet structure 3 is mounted on the outer peripheral surface of the envelope 1 so that the external electrodes 5 and 6 are located between the envelope 1 and the translucent sheet 4, and will be described later. In the second opening (8), one end 4a of the translucent sheet 4 and another end 4b are overlapped and bonded. In particular, when the sheet structure 3 is attached to the envelope 1, a first opening 7 is provided between the one ends 5a and 6a of the external electrodes 5 and 6, and the other ends 5b and 5b of the external electrodes 5 and 6 are provided. The second openings 8 are respectively formed between 6b, and the light from the light emitting layer 2 is mainly emitted from the first openings 7. The opening angles θ ₁ and θ ₂ of the first and second openings 7 and 8 are desirably set in a relationship of θ ₁ > θ ₂ , but may be set the same.
[0019]
This rare gas discharge lamp is manufactured, for example, as follows. First, as shown in FIG. 6A, the deformed portions 51A and 61A of the terminals 51 and 61 are overlapped on the ends of the external electrodes 5 and 6, respectively. Next, as shown in FIG. 6B, conductive adhesives 52 and 62 are provided on the overlapping portions of the external electrodes 5 and 6 and the terminals 51 and 61 and around the overlapping portions, and the deformed portions 51A and 61A are also enriched. And solidify. Thereby, the external electrodes 5 and 6 and the terminals 51 and 61 are electrically and mechanically connected. Next, as shown in FIG. 4C, external electrodes 5 and 6 are provided on one surface of the light-transmitting sheet 4 and the conductive adhesives 52 and 62 are attached to the light-transmitting sheet side. In addition, the terminals 51 and 61 are separated from each other so that the other ends of the terminals 51 and 61 protrude from the edge portions of the translucent sheet 4, and are bonded. Thereafter, an adhesive layer 9 is formed on one surface of the translucent sheet 4 and the exposed surfaces of the external electrodes 5 and 6 to complete the sheet structure 3. In addition, if an adhesive layer is formed on the exposed surfaces of the external electrodes 5 and 6 in advance, the step of forming the adhesive layer after attaching the external electrodes can be omitted.
[0020]
Next, as shown in FIG. 7, the sheet structure 3 is placed on a predetermined portion, for example, an assembly stage in a state where the sheet structure 3 is expanded. Next, the envelope 1 is placed parallel to one end 4a of the translucent sheet 4 of the sheet structure 3 so that the longitudinal direction of the envelope 1 is along the longitudinal direction of the external electrodes 5 and 6. So) position. In this state, the envelope 1 is rolled in the direction indicated by the arrow (the direction of the other end 4b of the translucent sheet 4) by slightly pressing the envelope 1 against the translucent sheet 4. As a result, the sheet structure 3 is wound around the outer peripheral surface of the envelope 1 as shown in FIG. 1, and the other end 4b is superimposed on one end 4a of the translucent sheet 4 and adhered. Glued by layer 9. When a thermosetting adhesive is used for the adhesive layer 9, it is desirable to perform a heat treatment.
[0021]
According to this rare gas discharge lamp, one ends of the terminals 51 and 61 are arranged so as to overlap with the ends of the external electrodes 5 and 6, and then electrically and mechanically connected by the conductive adhesives 52 and 62. However, since the conductive adhesives 52 and 62 are pasty in the applied state, the thickness thereof can be sufficiently reduced without requiring skill. For this reason, in a state where the sheet structure 3 is wound and closely attached to the outer peripheral surface of the envelope 1, the outer diameter of the discharge lamp is substantially equalized over the entire length, and the discharge lamp is locally localized at the end of the envelope. The outer diameter does not become large. Therefore, in the OA equipment, even if the installation space of the rare gas discharge lamp is considerably restricted, it can be reliably installed.
[0022]
On one end of each of the terminals 51 and 61, a deformed portion 51A or 61A made of, for example, a plurality of holes is formed, and the deformed portions 51A and 61A are filled with conductive adhesives 52 and 62. It is attached so that. For this reason, even in the solidified state, even if a tensile force acts on the terminals 51 and 61 in the lead-out direction, the terminals 51 and 61 are bitten by the deformed portions 51A and 61A and the conductive adhesives 52 and 62. You will not be escaped. Therefore, in the assembling work, since it is not necessary to pay close attention so that an undesired force does not act on the terminals 51 and 61, the work efficiency can be remarkably improved.
[0023]
In particular, if the relationship between the width W of the external electrodes 5 and 6 and the width d of the terminals 51 and 61 is set to 0.1 W ≦ d ≦ 0.5 W, the external electrodes 5 and 6 and the terminals 51 and 61 are directly connected. Even if they are brought into contact and then connected using the conductive adhesives 52 and 62, the occurrence of dissimilar metal contact corrosion can be suppressed. Therefore, a stable operation state can be maintained for a long period of time. However, when the width d of the terminals 51 and 61 is less than 0.1 W, the mechanical strength of the terminals themselves decreases, and it becomes difficult to form a deformed portion. Conversely, if the width d exceeds 0.5 W, in order to make the terminals 51 and 61 easily follow the outer peripheral surface of the envelope 1 when the sheet structure 3 is wound around the envelope 1. In addition, it is necessary to previously process the outer surface of the envelope 1 into a curved surface, which causes a problem that the processing is extremely troublesome. Therefore, it is desirable that both are set in the above-described relationship.
[0024]
On the other hand, according to the above-described manufacturing method, the external electrodes 5 and 6 can be adhered to the outer peripheral surface of the envelope 1 by simply rolling the envelope 1 on the sheet structure 3, Since the electrodes 5 and 6 are arranged on the translucent sheet 4 at a predetermined interval in advance, it is not necessary to adjust the interval between the external electrodes 5 and 6 to a predetermined interval when attaching the electrodes. In addition, even if manual work is performed, work efficiency can be significantly improved. Specifically, while the conventional method required 60 minutes for production, the method of the present invention can reduce the time to about 1 minute.
[0025]
In addition, since the adhesive layer 9 is formed on one surface of the translucent sheet 4 in the sheet structure 3, the envelope 1 is simply rolled on the sheet structure 3. The sheet structure 3 can be wound around and adhered to the outer peripheral surface of the envelope 1 by the simple operation of (1). Therefore, not only the work efficiency can be dramatically improved, but also mechanization becomes possible, and a further mass production effect can be expected.
[0026]
In addition, when the sheet structure 3 is wound and adhered to the outer peripheral surface of the envelope 1, the end portions 4a and 4b of the translucent sheet 4 are overlapped and adhered to each other. The coating reliability of the electrodes 5 and 6 can be improved. In particular, when the thickness of the translucent sheet 4 is set in the range of 20 to 100 μm, stable polymerization and adhesion of the ends 4a and 4b can be obtained. However, if the thickness is less than 20 .mu.m, sufficient insulation cannot be ensured. Conversely, if it exceeds 100 .mu.m, the stiffness of the sheet becomes so strong that the overlapped portions of the end portions 4a and 4b tend to peel off. , Winding work is also troublesome. Therefore, it is desirable to set the sheet thickness in the above range.
[0027]
The external electrodes 5 and 6 are arranged so as to be located between the translucent sheet 4 and the outer peripheral surface of the envelope 1 when the sheet structure 3 is mounted on the envelope 1. Therefore, even when applied to an OA device such as a facsimile machine and a high voltage is applied during use, sufficient insulation between the external electrodes as well as between the external electrodes can be ensured.
[0028]
FIG. 8 shows a different embodiment of the terminal 51 (61) according to the present invention. The terminal 51 in FIG. 8A has a semicircular notch in the same portion on both sides of one end. It is formed by forming a deformed portion 51A. The other end is formed wider than the one end so that connection such as harness is easy. The terminal 51 shown in FIG. 6B is formed by alternately forming the deformed portions 51A shown in FIG. Further, the terminal 51 shown in FIG. 3C is formed in a forked shape by forming a deformed portion 51A having a notch (notch) at the center of one end. These deformed portions 51A can be used in combination with each other or appropriately combined with the deformed portion 51A having a hole shown in FIG.
[0029]
FIGS. 9 and 10 show a second embodiment of the present invention, and the basic configuration is the same as that of the rare gas discharge lamp shown in FIGS. The difference is that an aperture portion (light emitting portion) 2a in which the light emitting layer 2 is not formed is formed in the inner surface portion of the envelope 1 corresponding to the first opening portion 7, and the external electrode 5 (6) and the terminal That is, a conductive adhesive 52 (62) for connecting to the outer peripheral surface of the envelope 1 is provided. The aperture angle of the aperture 2a is set, for example, in the range of 70 to 110 degrees, but can be changed as appropriate according to the use and purpose.
[0030]
According to this embodiment, the connection of the terminal 51 to the external electrode 5 is performed by superposing the terminal 51 on the end of the external electrode 5 arranged on the translucent sheet 4 and then applying the conductive adhesive 52. The assembly work can be further improved because it can be performed by applying and solidifying.
[0031]
Further, since the light emitted from the light emitting layer 2 is densified in the envelope and is emitted from the aperture portion 2a to the outside through the first opening 7, the light emitted from the light emitting layer 2 is applied to a document irradiation device. Thus, the illuminance of the document surface can be increased, and the reading accuracy of the document can be improved.
[0032]
In particular, if the surface of the outer electrodes 5 and 6 on the side of the envelope is provided with light reflectivity, the illuminance of the aperture portion 2a can be further increased, and the reading accuracy of the document can be further improved. As a material for this, a metal member having light reflectivity such as an aluminum foil is suitable.
[0033]
FIG. 11 shows a third embodiment of the present invention, and the basic configuration is the same as that of the rare gas discharge lamp shown in FIGS. The difference is that when the sheet structure 3 is wound around and adhered to the envelope 1, the main overlapping portions of the ends 4 a and 4 b of the translucent sheet 4 are connected to the outer surface of the external electrode 5. It is set to. Note that this overlapped portion may be on the outer surface side of the external electrode 5.
[0034]
FIG. 12 shows a fourth embodiment of the present invention. The basic configuration is the same as that of the rare gas discharge lamp shown in FIGS. The difference is that a protective tube 10 made of a heat-shrinkable resin is placed on the outer peripheral surface of the sheet structure 3. After the protective tube 10 is mounted on the envelope 1, it is heated to, for example, about 150 to 200 ° C. and shrunk to be closely attached to the sheet structure 3.
[0035]
According to this embodiment, when the environmental conditions in the application area of the rare gas discharge lamp are strict or the safety standards are high, for example, the protective tube 10 which is excellent in heat resistance and the like and has translucency. By coating the sheet structure 3 with the above, a higher quality product can be provided.
[0036]
In particular, the structure of this embodiment can be applied to the second and third embodiments shown in FIGS.
[0037]
A fifth embodiment of the present invention will be described with reference to the second and third embodiments shown in FIGS. In this embodiment, after a pair of external electrodes 5 and 6 are adhered to the outer peripheral surface of the envelope 1, the translucent sheet 4 is coated on the outer peripheral surface of the envelope 1 with the external electrodes 5 and 6. In this manner, the ends 4a and 4b of the translucent sheet 4 are overlapped and adhered while being wound and brought into close contact with each other. The terminal may be connected to the external electrode by a conductive adhesive before the external electrode is attached to the envelope, or may be connected after the external electrode is attached to the envelope. Good.
[0038]
According to this embodiment, although it is inferior in mechanization and work efficiency as compared with the above-described embodiments, it can be improved as compared with the conventional example. In particular, if an insulating coating such as a silicone varnish is formed on the outer peripheral surface of the envelope 1 before winding the translucent sheet 4, the insulating properties can be further improved. .
[0039]
Note that the present invention is not limited to the above-described embodiment, and the external electrodes in the sheet structure may be formed by attaching, for example, a predetermined shape, or by vapor deposition or thermal spraying. The attachment of the sheet structure to the outer peripheral surface of the envelope can be performed by rolling the envelope on the sheet structure, or by rotating the sheet structure and attaching the sheet structure. Can be used together. In addition, the ends of the sheet structure may be overlapped, butted, or processed to form a slight gap. Further, the width between the external electrode and the terminal can be set to a value other than the above-mentioned relationship in the case where the dissimilar metal contact corrosion is not a problem.
[0040]
【Example】
Next, an experimental example will be described. The sheet structure shown in FIG. 4 is wound and adhered to an envelope made of lead glass having an outer diameter of 8 mm and a length of 300 mm. In the sheet structure, strip-shaped aluminum having a thickness of 70 μm and a width W of 8 mm was used for external electrodes, and strip-shaped copper having a thickness of 0.15 mm and a width d of 2 mm was used for terminals. Three semi-circular irregular parts having a radius of 0.5 mm are formed on both sides of the end portion of each of the two ends, and both of them are two-part cold curing adhesive 3381 (acrylic containing nickel powder) manufactured by Three Bond Co., Ltd. They are electrically and mechanically connected by a conductive adhesive. This rare gas discharge lamp was placed in an atmosphere having an ambient temperature of 60 ° C. and a relative humidity of 90%, and an acceleration test was performed in which a high-frequency high voltage of 27 KHz and 2000 Vo-p was applied to the external electrodes via terminals. Even after the lapse of 1500 hours, no corrosion was observed at the connection between the external electrode and the terminal. However, the width d of the terminal is set to 4.5 mm, and the external electrode and the terminal are made of aluminum made of lead (59%)-tin (40%)-silver (0.5%)-antimony (0.5%). In the conventional product having the same configuration as the product of the present invention except that it was connected by solder, it was recognized that the corrosion started to progress after 700 hours.
[0041]
This is because, in the product of the present invention, the width d of the copper terminal having a high corrosion potential is sufficiently narrow to about 0.25 with respect to the width W of the external electrode made of aluminum having a low corrosion potential. Is assumed to have been suppressed. However, in the conventional product, it is 0.56, and since the progress of corrosion was recognized in this state, the relation between the terminal width d and the external electrode width W was set to d = 0.1 W to 0.5 W. It is desirable to do.
[0042]
Also, in the product of the present invention, the variation in the outer diameter (maximum value-minimum value) was 0.42 mm, whereas in the conventional product, the variation was 2.6 mm. For this reason, the product of the present invention did not cause any trouble in assembling into a miniaturized OA device, but the conventional product caused trouble in assembling. This is presumably because the terminals of the product of the present invention are arranged in the cutouts of the external electrodes.
[0043]
Furthermore, in the product of the present invention, the terminal was not detached from the external electrode even if a tensile force of 2 kg was applied to the terminal after 1500 hours.
[0044]
【The invention's effect】
As described above, according to the present invention, one end of the terminal is arranged so as to overlap the end of the external electrode, and is electrically and mechanically connected by the conductive adhesive. In this case, since the conductive adhesive has a paste shape, the thickness can be sufficiently reduced without requiring skill. For this reason, in a state where the sheet structure is wound and closely attached to the outer peripheral surface of the envelope, the outer diameter of the discharge lamp is substantially equalized over the entire length, and the outer diameter is locally reduced at the end of the envelope. The diameter does not increase. Therefore, in the OA equipment, even if the installation space of the rare gas discharge lamp is considerably restricted, it can be reliably installed.
[0045]
In addition, a deformed portion composed of a notch and / or a hole is formed at one end of the terminal, and the deformed portion is covered with the conductive adhesive so as to be solid. For this reason, in the solidified state, even if a tensile force acts on the terminal in the lead-out direction, the detachment of the terminal can be effectively suppressed by the bite between the deformed portion and the conductive adhesive. Therefore, in the assembling work, since it is not necessary to pay close attention so that an undesired force does not act on the terminal, the work efficiency can be significantly improved.
[0046]
In particular, if the relationship between the width W of the external electrode and the width d of the terminal is set to 0.1 W ≦ d ≦ 0.5 W, the external electrode and the terminal are brought into direct contact with each other, and then the conductive adhesive is used. Connection can suppress the occurrence of dissimilar metal contact corrosion. Therefore, a stable operation state can be maintained for a long period of time.
[0047]
When a sheet structure is used, the external electrodes can be adhered to the outer peripheral surface of the envelope simply by rolling the envelope on the sheet structure, and the external electrodes can be transparent. Since the sex sheets are arranged at predetermined intervals in advance, there is no need to adjust the intervals between the external electrodes at the time of attachment so as to be at the predetermined intervals. Therefore, not only the work efficiency can be dramatically improved, but also mechanization becomes possible, and a further mass production effect can be expected.
[0048]
Further, the external electrode is designed to be located between the translucent sheet and the outer peripheral surface of the envelope when the sheet structure is mounted on the envelope. Even if a high voltage is applied during use by applying to the OA equipment, sufficient insulation between the external electrodes as well as between the external electrodes can be ensured.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.
FIG. 2 is a sectional view taken along line XX of FIG.
FIG. 3 is a side view in a partially broken state of FIG. 1;
FIG. 4 is a development view of a sheet structure according to the present invention.
FIG. 5 is a sectional view taken along line YY of FIG. 4;
6A and 6B are plan views for explaining a method of assembling a sheet structure according to the present invention, wherein FIG. 6A shows a state where terminals are arranged at ends of external electrodes, and FIG. ) Shows a state in which the terminal and the external electrode are connected by a conductive adhesive, and FIG. 3C shows a state in which the external electrode is arranged at a predetermined position on the translucent sheet.
FIG. 7 is a longitudinal sectional view for explaining the method of the present invention.
FIGS. 8A and 8B are plan views showing different embodiments of the terminal according to the present invention, in which FIG. 8A shows a terminal in which a notch-shaped irregular portion is formed, and FIG. FIG. 3C shows a terminal in which notched irregular portions are alternately formed, and FIG. 3C shows a terminal in which a deformed portion formed of a slit-shaped notch is formed and the end portion is formed in a forked shape.
FIG. 9 is a longitudinal sectional view showing a second embodiment of the present invention.
FIG. 10 is a sectional view of a main part of FIG. 9;
FIG. 11 is a longitudinal sectional view showing a third embodiment of the present invention.
FIG. 12 is a longitudinal sectional view showing a fourth embodiment of the present invention.
FIG. 13 is a longitudinal sectional view of a conventional example.
FIG. 14 is a perspective view for explaining a conventional method.
FIG. 15 is a sectional view taken along the line ZZ of FIG. 13;
[Explanation of symbols]
W width of external electrode d width of terminal 1 envelope 2 light emitting layer 2a aperture part 3 sheet structure 4 translucent sheet 5, 6 external electrode 51, 61 terminal 51A, 61A deformed part 52, 62 Conductive adhesive 7 First opening 8 Second opening 9 Adhesive layer 10 Protection tube

Claims

A straight tubular envelope having a light-emitting layer on the inner surface, a pair of strip-shaped external electrodes made of a metal member arranged on the outer peripheral surface of the envelope over substantially the entire length thereof, And a terminal made of a metal different from the external electrode derived from the end of the external electrode, and a light-transmitting device mounted on the outer peripheral surface of the envelope so as to cover the external electrode. A terminal formed with a notch and / or a hole in the terminal, and the width W of the external electrode and the substantial width d of the terminal are set to 0.1 W ≦. A rare gas discharge lamp characterized by setting d ≦ 0.5 W and electrically connecting the terminal and the external electrode with a conductive adhesive.

2. The rare gas discharge lamp according to claim 1, wherein the light-transmitting insulating member is formed of a protective tube made of a light-transmitting sheet or a heat-shrinkable resin.

A straight tubular envelope having a light-emitting layer on the inner surface, and a pair of strip-shaped external electrodes made of a metal member on one surface of a translucent sheet having a length substantially equal to the entire length of the envelope. A sheet structure that is electrically and mechanically connected to a terminal having a deformed portion formed of a metal different from the external electrode at an end of the external electrode and arranged at a distance from each other, with a conductive adhesive; The width W of the external electrode and the substantial width d of the terminal are set in a relationship of 0.1 W ≦ d ≦ 0.5 W, and the deformed portion of the terminal is formed by notches and / or holes. A rare gas , wherein a sheet structure is wound and adhered to an outer peripheral surface of the envelope so that an external electrode is located between the envelope and the translucent sheet. Discharge lamp.