JP3827428B2

JP3827428B2 - Tube closure and tube

Info

Publication number: JP3827428B2
Application number: JP32398697A
Authority: JP
Inventors: 正伸小宮; 哲竹村; 幸治田川
Original assignee: Ushio Denki KK
Current assignee: Ushio Denki KK
Priority date: 1997-11-11
Filing date: 1997-11-11
Publication date: 2006-09-27
Anticipated expiration: 2017-11-11
Also published as: JPH11144680A

Description

【０００１】
【発明の属する技術分野】
本発明は水銀ランプやキセノンランプやメタルハライドランプ等の放電ランプ、またはハロゲンランプやハロゲンヒータ等の白熱電球の閉塞管部を閉塞する傾斜機能材料からなる管球用閉塞体、および管球用閉塞体を使用した管球に関する。
【０００２】
【従来の技術】
最近、シリカガラス製の発光管内に一対の電極が対向配置された放電ランプの発光管に連設された閉塞管を封止する閉塞体として、傾斜機能材料が使用され始めている。傾斜機能材料で形成された閉塞体は、一方側がシリカなどの絶縁性無機物質成分に富み、他方側に向かうにつれてモリブデンなどの導電性無機物質成分の割合が連続的にまたは段階的に増加するものである。
したがって、例えばシリカとモリブデンからなる傾斜機能材料を使用した閉塞体の場合、該閉塞体の一方の側は絶縁性であるとともに熱膨張率が発光管材料のシリカガラスの熱膨張率に同じかまたは近く、他方の側は導電性であるとともに熱膨張率が電極芯棒の材料であるタングステンまたはモリブデンの熱膨張率に近いという特性を有する。この特性が管球の閉塞体として適している。
【０００３】
管球の中で、フィラメント発熱体を有するハロゲンランプやハロゲンヒータ等の白熱電球においてもその発光管はシリカガラス製であるので、閉塞体としてこの傾斜機能材料を使用できる。
【０００４】
図１は放電ランプの閉塞体として傾斜機能材料を使用した従来の放電ランプの例の断面図を示す。放電ランプ１の発光管２および閉塞管３は絶縁性無機物質成分（例えばシリカガラス）製であり、発光管２内部に対向した一対の電極５、５が配置されている。前記両電極は電極芯棒６の先端にあり、該電極芯棒６は閉塞体４の導電性部分４１まで挿入され焼き嵌められている。記号７は外部リードであり、電極芯棒と同様に焼き嵌められている。なお、外部リード７と電極芯棒６を一体として、閉塞体４を貫通して焼き嵌められることもある。
【０００５】
閉塞体４は円柱状であり、軸方向に一様な外径を有し、絶縁性無機物質成分（例えばシリカ）と導電性無機物質成分（例えばモリブデン）から形成されており、該閉塞体４の一方の側（発光管内方側）は絶縁性無機物質成分に富み絶縁性部分４０であり、他方側（発光管外方側）は導電性無機物質成分に富み導電性部分４１である。そして、絶縁性無機物質成分側端面は放電ランプ１の発光管２の放電空間に面するように配置され、該発光管２の両端に形成された閉塞管３は閉塞体４の絶縁性部分４０にて気密に溶着封止される。
【０００６】
傾斜機能材料製の閉塞体を管球の閉塞体として使用する場合は、従来は図１に示すように傾斜機能材料の絶縁性部分４０を閉塞管３で覆い溶着封止して傾斜機能材料製閉塞体４を閉塞管３から突出させて該閉塞体４の導電性部分４１を直接帯状の口金１０で挟んで給電する構成としていた（閉塞体突出型）。
しかし、該閉塞体の折損防止のため、最近では図２に示すように閉塞管３を延長して該閉塞体４より長くして閉塞体を保護する「保護管」の役割を閉塞管に持たせ、これに口金１０を接着材１７で固定するという方式が用いられることも行われる（保護管型）。
図２の構造の放電ランプにおいては、閉塞体４の導電性部分端面から突出した外部リード棒７が外部リード棒延長線９と溶接部８で溶接され、該外部リード棒延長線９は口金１０のロウ付部１１でロウ付けされている。
【０００７】
前述の「閉塞体突出型」の方式では、閉塞体４の絶縁性部分４０での溶着封止では発光管２内を負圧にした状態で閉塞管３における閉塞体４の絶縁性部分４０の位置する個所を閉塞管の外側から火炎バーナーで加熱することにより、閉塞管３を溶融させて縮径するように変形させ、閉塞管３と閉塞体４の絶縁性部分４０とを気密に溶着する。
【０００８】
そして、後者の「保護管型」の方式において、軸方向で一定の外径を有する円柱状閉塞体４を使用した場合、閉塞管３内壁と閉塞体４の絶縁性部分４０を密着させるように溶着封止する過程では、接合のまさに離れる箇所、すなわち閉塞体の被溶着封止部分外端で、図３に示すように鋭い角度を持ってガラスが傾斜機能材料製閉塞体から離間する。また、溶着接合面の外縁部が波を打ったような状態になり、形状的にも制御しにくかった。
【０００９】
つまり、「保護管型」の方式においても、前記被溶着封止部分外端がエッジ部１２となっており、そのエッジ部１２が応力に対して弱い構造的特異点となり、溶着封止する際に放電ランプに力がかかりエッジ部１２に応力集中が起こりやすい。そして、ついにはエッジ部１２で閉塞体４が折れるという不具合が発生する。
【００１０】
さらに、「保護管型」の構成の放電ランプを組立製作する際に、傾斜機能材料製閉塞体４から突出した外部リード棒７に外部リード棒延長線９を溶接部８でスポット溶接したり、口金１０の中に該延長線９を挿入するときなどに放電ランプに力が加わり、特異点である前記エッジ部１２で折れてしまうことがある。
【００１１】
【発明が解決しようとする課題】
そこで本発明の目的は、放電ランプや白熱電球等の管球の封止工程および封止工程後の組立製作過程において、閉塞管の閉塞体との被溶着封止部分端部で折れて破損することの少ない管球用閉塞体とそれを用いた管球を提供することにある。
【００１２】
【課題を解決するための手段】
上記課題を解決するために、請求項１記載の発明は、管球の発光管に連設された閉塞管を封止する管球用閉塞体であって、導電性無機物質成分および絶縁性無機物質成分からなり、軸方向に沿って導電性無機物質成分濃度が傾斜的に変化することによって導電性部分と絶縁性部分が形成された略柱状の傾斜機能材料から構成されており、かつ前記閉塞管が溶着封止される被溶着封止部分外端に連続して外周面に溝部を形成したことを特徴とする管球用閉塞体とする。
【００１３】
次に請求項２記載の発明は、管球の発光管に連設された閉塞管を封止する管球用閉塞体であって、導電性無機物質成分および絶縁性無機物質成分からなり、軸方向に沿って導電性無機物質成分濃度が傾斜的に変化することによって導電性部分と絶縁性部分が形成された略柱状の傾斜機能材料から構成されており、かつ前記閉塞管が溶着封止される被溶着封止部分外端より外方にかけての部分の外径を被溶着封止部分の外径より小さくなるように外周面に段差を付けたことを特徴とする管球用閉塞体とする。
【００１４】
さらに、請求項３記載の発明は、発光管と該発光管に連設された閉塞管と該閉塞管を閉塞する閉塞体を有する管球において、該閉塞体は、導電性無機物質成分および絶縁性無機物質成分からなり、軸方向に沿って導電性無機物質成分濃度が傾斜的に変化することによって導電性部分と絶縁性部分が形成された略柱状の傾斜機能材料から構成されており、かつ前記閉塞管が溶着封止される被溶着封止部分外端に連続して外周面に溝部を形成してあり、該閉塞管は、該閉塞体の被溶着封止部分よりも長い長さを有し、閉塞体の被溶着封止部分より外側にまで延びていることを特徴とする管球とする。
【００１５】
そして、請求項４記載の発明は、発光管と該発光管に連設された閉塞管と該閉塞管を閉塞する閉塞体を有する管球において、該閉塞体は、導電性無機物質成分および絶縁性無機物質成分からなり、軸方向に沿って導電性無機物質成分濃度が傾斜的に変化することによって導電性部分と絶縁性部分が形成された略柱状の傾斜機能材料から構成されており、かつ前記閉塞管が溶着封止される被溶着封止部分外端より外方にかけての部分の外径を被溶着封止部分の外径より小さくなるように外周面に段差を付けてあり、該閉塞管は、該閉塞体の被溶着封止部分よりも長い長さを有し、閉塞体の被溶着封止部分より外側にまで延びていることを特徴とする管球とする。
【００１６】
また、請求項５に記載の発明は、前記閉塞管が溶着封止される被溶着封止部分外端の導電性無機物質成分濃度が０体積％以上３体積％以下であることを特徴とする請求項１または請求項２に記載の閉塞体とする。
【００１７】
【作用】
閉塞管が溶着封止される被溶着封止部分外端に連続して外周面に溝部を形成したり、閉塞管が溶着封止される被溶着封止部分外端近傍より外方にかけての部分の外径を被溶着封止部分の外径より小さくなるように外周面に段差をつけた閉塞体とすると、被溶着封止部分外端に形成されるエッジ部のエッジ角度の鋭さが軽減されるので管球にかかる応力に対しての閉塞体のエッジ部の機械的強度が増し、管球の機械的強度も増す。
【００１８】
【発明の実施の形態】
次に図面を用いて本発明の実施の形態を説明する。本発明の閉塞体を構成する傾斜機能材料の製造方法については概略次の通りである。
絶縁性無機物質成分粉末と導電性無機物質成分粉末との混合割合が異なった混合粉末体を複数種類用意し、有機バインダを含む溶剤とともに混合した後、造粒された絶縁性無機物質成分粉末と導電性無機物質成分粉末との混合割合毎に均一組成層を積層し加圧して円柱状の成形体とする。
【００１９】
図９に傾斜機能材料を成形するときの加圧方法を示すが、円柱状の成形空間を有する金型２０の底部材２２の上面上に、導電性無機物質成分濃度の最も低い混合粉末を層状に充填して、ついで２番目に低い導電性無機物質成分濃度の混合粉末を層状に充填し、そのように順に導電性無機物質成分濃度を変えた混合粉末を層状に必要な層数充填し、その後加圧体２１で加圧して成形することにより、複数層が一体に積層された成形層積層体２３を形成する。図９では５層の状態が示されている。その後、有機バインダを除去する仮焼結を行なう。
【００２０】
仮焼結後、成形層積層体２３の絶縁性側端面の略中心に該端面表面から該閉塞体の導電性部分までいたる電極芯棒と略同径の電極芯棒挿入用の孔を加工する。
【００２１】
次に、本発明においては閉塞管が溶着封止される閉塞体の被溶着封止部分外端に連続した外周面を旋盤を使用して削って溝きりするか、同じく旋盤で閉塞体の封止されない部分の外周面を削る。そして、電極芯棒挿入用の孔に電極芯棒を挿入してから本焼結する。
【００２２】
なお、図１１に示したハロゲンランプ等の白熱電球の場合には、電極芯棒６に替えて内部リード棒１６を閉塞体の孔に挿入して本焼結をする。
【００２３】
他に本発明の閉塞体の作り方としては、例えば図１０に示すように完成後の閉塞体の形（閉塞体の溶着されない部分の径を被溶着封止部分の径より小さくした形）にした内面形状の金型２０を使用してそれぞれが均一組成の複数層が一体に積層された均一層積層体を形成してもよい。
【００２４】
そして出来上がった閉塞体は放電ランプの閉塞管部に酸水素バーナー等の火炎バーナーで溶着封止される。
【００２５】
【実施例】
次に本発明の実施例を具体的に説明する。
傾斜機能材料としては、絶縁性無機物質成分としてシリカ（ＳｉＯ_２）を、導電性無機物質成分としてモリブデン（Ｍｏ）を使用した。
平均粒径１．０μｍのモリブデン粉末と平均粒径５．６μｍのシリカ粉末を準備し、シリカの体積割合を変えた混合粉末体を調製し、その混合粉末体にステアリン酸を混合して造粒体とし、図９に示した金型２０内にシリカの体積割合の多い順に積層し、加圧体２１によって１．５ｔ／ｃｍ^２の荷重で軸方向に圧縮し、円柱状の成形層積層体２３を得た。そして、成形層積層体２３を水素ガス中、１２００℃で３０分仮焼結し、有機バインダを除去した。
【００２６】
仮焼結後、傾斜機能材料製閉塞体のシリカ側端面に電極芯棒挿入用の孔開け加工を施した。そして、閉塞体の被溶着封止部分外端に連続する外周面を旋盤を使用して削って溝きりした。傾斜機能材料製閉塞体の寸法は軸方向の全長が１２ｍｍ、径方向の外径が２．１ｍｍである。溝の深さは０．１〜０・５ｍｍが適当な深さであり、本実施例においては０．２乃至０．３ｍｍとした。また、溝きりした箇所の位置はシリカ側端面から５ｍｍとした。なお、傾斜機能材料のモリブデン濃度が濃すぎると閉塞管と封止したときに閉塞体にクラックが入ることから、溝位置は傾斜機能材料製造の設計の際に決まる軸方向のモリブデン濃度分布に依存する。
【００２７】
次に、タングステン製電極芯棒を電極芯棒挿入用の孔に挿入し、真空雰囲気において１８２０℃で５分間加熱して電極芯棒を焼き嵌める本焼結処理を行なった。
【００２８】
傾斜機能材料製閉塞体を閉塞管と溶着する場合、閉塞体の絶縁性部分で溶着するが、閉塞管材料であるシリカと溶着される閉塞体の部分の熱膨張係数の関係から、従来は、傾斜機能材料のモリブデン濃度が体積％で０％〜１．７％の領域までが閉塞管との溶着封止可能領域とみなされていた。
しかし、発明者等の鋭意研究の結果、傾斜機能材料のモリブデン濃度が体積％で１．７％を超え３％の領域までは閉塞体にクラックが入らずに閉塞管と溶着できることを確認した。すなわち、モリブデン濃度０〜３ｗｔ％までの範囲で閉塞体を閉塞管に封止可能であり、封止領域の幅を比較的広くとることができ、一層気密な溶着封止ができる。
【００２９】
図２は従来から使用されている円柱状の傾斜機能材料製閉塞体を閉塞管の封止に使用した、閉塞管を閉塞体の被溶着封止部分よりも長くした放電ランプの断面図を示しており、被溶着封止部分の外径Ａは溶着封止されない部分の外径Ｂと等しい（Ａ＝Ｂ）。それに対して、図４乃至図８および図１１は本発明の管球用閉塞体を放電ランプに適用した実施例を示す部分断面図である。図６中のＣは溝部の外径である。図４の例ではＡ＞Ｂであり、図６の例ではＡ＝ＢかつＡ＞Ｃ、図７の例ではＡ＞Ｂ＞Ｃの関係にある。
図８の例では、閉塞体の発光空間に面した側にテーパー部１４を形成しており、発光管内ガス耐圧が強くなっている。このテーパー部は閉塞体を旋盤にかけて超硬バイトの刃を閉塞体の斜めから当てて切削することによって形成した。
図１１は白熱電球としてのハロゲンランプに本発明の閉塞体を使用した例である。
【００３０】
次に、本発明の傾斜機能材料製閉塞体とその閉塞体を使用した本発明の管球としての放電ランプと従来の円柱状傾斜機能材料製閉塞体とその閉塞体を使用した放電ランプを実際に製作した際の破損割合を調べた結果を説明する。
本発明の閉塞体を使用した放電ランプは図４に示した形状であり、従来の閉塞体を使用した放電ランプは図２に示した形状である。
【００３１】
製作した放電ランプに使用した閉塞体の寸法は次の通りである。

【００３２】
準備した閉塞体は従来品５０個、本発明品１００個であり、比較検討のためにそれぞれの閉塞体を使用して放電ランプを製作した。
従来型の閉塞体を放電ランプの閉塞体として使用したとき、閉塞体と閉塞管の溶着封止の工程で、放電ランプ５０本中１０本の閉塞体が被溶着封止部分外端のエッジ部で折れて破損した。さらに溶着封止工程の際に残った４０本において、口金を取りつけたりするランプ組立製作の間に５本が破損した。つまり、５０本中１５本が破損した。
【００３３】
一方で、本発明品の閉塞体を放電ランプの閉塞体として使用したとき、閉塞体と閉塞管の溶着封止の工程で放電ランプ１００本中閉塞体が折れて破損したのは０本であり、口金を取りつけたりするランプ組立製作の間には１本しか破損しなかった。つまり、１００本中破損したのはわずかに１本であった。
このように、被溶着封止部分外端に連続して外周面に溝部を形成したことによって明らかに管球の封止工程および封止工程後の組立製作過程において閉塞管部で折れて破損することの少ない管球を得ることができることがわかる。
【００３４】
これは、本発明が図６のように被溶着封止部分外端であるエッジ部１２に連続する外周面に溝部１３を、または図４に示すように被溶着封止部分外端であるエッジ部１２から導電性部分４１にかけて小径部を形成してあるので、図５に示すように被溶着封止部分外端から閉塞管内面と閉塞体外面のなす角（θ）が大きいものとなり、従来の図３のように鋭いエッジ部がないことによるものである。
【００３５】
上述の実施例の説明では、シリカとモリブデンの組み合わせからなる傾斜機能材料製閉塞体で説明したが、絶縁性無機物質成分としてはアルミナ、ジルコニア、マグネシア、炭化ケイ素、窒化ケイ素、炭化チタン、などが実用的材料として使用可能であり、導電性無機物質成分としては、ニッケル、タングステン、タンタル、クロム、白金などが実用的材料として使用可能である。
【００３６】
また、閉塞体形状も円柱型に限らず、軸に垂直な断面が多角形状の角柱体であってもいい。ただし、多角形状の角柱体の場合は外径ではなく、断面の最大寸法が被溶着封止部分より溶着封止されない部分の方で小径であるということになる。
【００３７】
【発明の効果】
以上詳細に説明したように、請求項１の発明による管球用閉塞体を使用することによって、閉塞管部の被溶着封止部分外端のエッジ部の角度の鋭さを軽減しランプの製造過程にランプが折れて破損することの無い管球とすることができる。
【００３８】
請求項２の発明による管球用閉塞体を使用すれば、閉塞体の溶着されない部分の外径が小さいので閉塞管の内径と接触することがなく、一層管球は破損に強くなる。
【００３９】
請求項３の発明による管球は、閉塞体が被溶着封止部分外端に連続する外周面に溝部を形成しているので、被溶着封止部分のエッジ部の角度の鋭さがなくなり、エッジ部の機械的強度が増すので折れにくく、また閉塞管も閉塞体全体を覆っているので保護管として充分機能する。
【００４０】
請求項４の発明による管球は、閉塞管が溶着封止される閉塞体の被溶着封止部分外端より外方にかけての部分の外径を被溶着封止部分の外径より小さくなるように外周面に段差を付けてあるので、被溶着封止部分のエッジ部の角度の鋭さがなくなり、エッジ部の機械的強度が増すので折れにくく、また閉塞管も閉塞体全体を覆っているので保護管として充分機能する。
【００４１】
請求項５の発明によれば、モリブデン濃度０〜３ｗｔ％までの範囲で傾斜機能材料製閉塞体を閉塞管に封止可能であり、溶着封止領域を広くとることができ、従来より一層気密な溶着封止ができる。
【図面の簡単な説明】
【図１】放電ランプの閉塞体として傾斜機能材料を使用した従来の放電ランプの例の部分断面図を示す。
【図２】従来の傾斜機能材料製閉塞体を使用した放電ランプの部分断面図を示す。
【図３】図２で示した放電ランプの部分断面図のエッジ部の拡大図を示す。
【図４】本発明にかかる傾斜機能材料製閉塞体を放電ランプに適用した実施例の部分断面図を示す。
【図５】図４で示した放電ランプの部分断面図のエッジ部の拡大図を示す。
【図６】本発明にかかる傾斜機能材料製閉塞体とそれを用いた放電ランプの他の実施例の部分断面図を示す。
【図７】本発明にかかる傾斜機能材料製閉塞体とそれを用いた放電ランプの他の実施例の部分断面図を示す。
【図８】本発明にかかる傾斜機能材料製閉塞体とそれを用いた放電ランプの他の実施例の部分断面図を示す。
【図９】傾斜機能材料製閉塞体を成形するときの一般的加圧方法の図を示す。
【図１０】本発明の傾斜機能材料製閉塞体を成形するときの一例としての加圧方法の図を示す。
【図１１】本発明の傾斜機能材料製閉塞体とそれを用いた白熱電球の断面図を示す。
【符号の説明】
１放電ランプ
２発光管
３閉塞管
４閉塞体
５電極
６電極芯棒
７外部リード棒
８溶接部
９外部リード棒延長線
１０口金
１１ロウ付け部
１２エッジ部
１３溝部
１４テーパー部
１５フィラメント
１６内部リード棒
１７接着材
２０金型
２１加圧体
２２底部材
２３成形層積層体
４０絶縁性部分
４１導電性部分
Ａ閉塞体の被溶着封止部分の外径
Ｂ閉塞体の溶着封止されない部分の外径
Ｃ閉塞体の溝部の外径[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a closed tube for a tube and a closed tube for a tube made of a functionally gradient material for closing a closed tube of a discharge lamp such as a mercury lamp, a xenon lamp or a metal halide lamp, or an incandescent lamp such as a halogen lamp or a halogen heater It relates to the tube using.
[0002]
[Prior art]
Recently, a functionally graded material has begun to be used as a closing body that seals a closing tube connected to an arc tube of a discharge lamp in which a pair of electrodes are opposed to each other in a silica glass arc tube. Occlusion body made of functionally gradient material is rich in insulating inorganic substance components such as silica on one side, and the proportion of conductive inorganic substance components such as molybdenum increases continuously or stepwise toward the other side It is.
Therefore, for example, in the case of a closed body using a functionally graded material composed of silica and molybdenum, one side of the closed body is insulative and the thermal expansion coefficient is the same as that of silica glass of the arc tube material or The other side is conductive and has a characteristic that the coefficient of thermal expansion is close to that of tungsten or molybdenum, which is the material of the electrode core bar. This property is suitable as a tube closure.
[0003]
Among the bulbs, incandescent lamps such as halogen lamps and halogen heaters having a filament heating element, the arc tube is made of silica glass, so that this functionally graded material can be used as a closure.
[0004]
FIG. 1 shows a cross-sectional view of an example of a conventional discharge lamp using a functionally gradient material as a closure for a discharge lamp. The arc tube 2 and the closing tube 3 of the discharge lamp 1 are made of an insulating inorganic substance component (for example, silica glass), and a pair of

electrodes

5 and 5 facing the inside of the arc tube 2 are arranged. Both electrodes are at the tip of the electrode core 6, and the electrode core 6 is inserted and shrink-fitted to the conductive portion 41 of the closing body 4. Symbol 7 is an external lead, which is shrink-fitted similarly to the electrode core bar. In some cases, the external lead 7 and the electrode core rod 6 are integrated and shrink-fitted through the closing body 4.
[0005]
The closing body 4 has a cylindrical shape, has a uniform outer diameter in the axial direction, and is formed of an insulating inorganic substance component (for example, silica) and a conductive inorganic substance component (for example, molybdenum). One side (the inner side of the arc tube) is rich in an insulating inorganic substance component and is an insulating part 40, and the other side (outer side of the arc tube) is a conductive part 41 rich in a conductive inorganic substance component. The insulating inorganic substance component side end face is disposed so as to face the discharge space of the arc tube 2 of the discharge lamp 1, and the closing tube 3 formed at both ends of the arc tube 2 is the insulating portion 40 of the closing body 4. And hermetically sealed.
[0006]
When using a block made of functionally graded material as a closed body of a tube, conventionally, as shown in FIG. 1, the insulating portion 40 of the functionally graded material is covered with the closed tube 3 and welded and sealed. The closing body 4 is protruded from the closing tube 3 and the conductive portion 41 of the closing body 4 is directly sandwiched between the band-shaped bases 10 to supply power (closing body protruding type).
However, in order to prevent breakage of the obstruction body, recently, the obstruction pipe has a role of “protection tube” that protects the obstruction body by extending the obstruction pipe 3 to be longer than the obstruction body 4 as shown in FIG. In addition, a method of fixing the base 10 with an adhesive 17 is used for this (protective tube type).
In the discharge lamp having the structure of FIG. 2, the external lead bar 7 protruding from the conductive part end face of the closure 4 is welded to the external lead bar extension line 9 and the welded portion 8, and the external lead bar extension line 9 is connected to the base 10. The brazing part 11 is brazed.
[0007]
In the above-described “occlusion body protruding type” system, in the welding sealing at the insulating portion 40 of the obstruction body 4, the insulating portion 40 of the obstruction body 4 in the obstruction tube 3 is in a state where the arc tube 2 is under negative pressure. The location is heated by a flame burner from the outside of the closing tube, so that the closing tube 3 is melted and deformed so as to reduce its diameter, and the closing portion 3 and the insulating portion 40 of the closing body 4 are welded in an airtight manner. .
[0008]
In the latter “protection tube type” method, when the cylindrical block body 4 having a constant outer diameter in the axial direction is used, the inner wall of the block tube 3 and the insulating portion 40 of the block body 4 are brought into close contact with each other. In the process of welding and sealing, the glass is separated from the functionally graded material closing body with a sharp angle as shown in FIG. Further, the outer edge portion of the welded joint surface is in a state of undulation, and it is difficult to control the shape.
[0009]
That is, even in the “protection tube type” system, the outer end of the welded sealing portion is an edge portion 12, and the edge portion 12 becomes a structural singular point that is weak against stress. As a result, a force is applied to the discharge lamp and stress concentration tends to occur at the edge portion 12. And finally, the malfunction that the obstruction | occlusion body 4 bends by the edge part 12 generate | occur | produces.
[0010]
Further, when assembling and manufacturing the discharge lamp having the “protection tube type” configuration, the external lead rod extension line 9 is spot welded to the external lead rod 7 protruding from the functionally graded material closing body 4 at the welding portion 8, When the extension wire 9 is inserted into the base 10, a force is applied to the discharge lamp, and the edge portion 12, which is a singular point, may break.
[0011]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to break and break at the end of the sealed portion of the closed tube to be welded with the closed body in the sealing process of the tube such as a discharge lamp or an incandescent bulb and the assembly manufacturing process after the sealing process. It is an object of the present invention to provide a tube-occlusion body and a tube using the same.
[0012]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a first aspect of the present invention is a tube closure body for sealing a closure tube connected to a tube arc tube, comprising a conductive inorganic substance component and an insulating inorganic material. The material is composed of a substantially column-shaped functionally gradient material in which a conductive portion and an insulating portion are formed by changing the concentration of the conductive inorganic material component in a gradient along the axial direction. A closed tube body characterized in that a groove is formed in the outer peripheral surface continuously to the outer end of the welded sealed portion where the tube is welded and sealed.
[0013]
Next, the invention according to claim 2 is a tube closure for sealing a tube closed to a tube arc tube, comprising a conductive inorganic material component and an insulating inorganic material component. It is composed of a substantially columnar functionally graded material in which a conductive portion and an insulating portion are formed by changing the concentration of the conductive inorganic substance component in a gradient along the direction, and the closed tube is welded and sealed. the outer diameter of the portion ranging outward and tube for closure, characterized in that stepped on the outer circumferential surface so as to be smaller than the outer diameter of the welded sealing portion than the welding sealing portion outer end that .
[0014]
Furthermore, the invention according to claim 3 is a tube having a luminous tube, a closed tube connected to the luminous tube, and a closed body for closing the closed tube, wherein the closed body includes a conductive inorganic substance component and an insulating material. Composed of a conductive inorganic substance component, composed of a substantially column-shaped functionally gradient material in which a conductive portion and an insulating portion are formed by changing the concentration of the conductive inorganic material component in an inclined direction along the axial direction, and A groove portion is formed in the outer peripheral surface continuously to the outer end of the welded sealed portion where the closed tube is welded and sealed, and the closed tube has a longer length than the welded sealed portion of the closed body. And a tube characterized by extending to the outside of the welded and sealed portion of the closing body .
[0015]
According to a fourth aspect of the present invention, there is provided a tube having an arc tube, an occlusion tube connected to the arc tube, and an occlusion body that occludes the occlusion tube, wherein the occlusion body includes a conductive inorganic substance component and an insulating material. Composed of a conductive inorganic substance component, composed of a substantially column-shaped functionally gradient material in which a conductive portion and an insulating portion are formed by changing the concentration of the conductive inorganic material component in an inclined direction along the axial direction, and the closing tube Yes with a step on the outer peripheral surface so as to be smaller than the outer diameter of the welded sealing parts of the outer diameter of the portion ranging outward from the welding sealing portion outer end which is sealed welded seal, said closure The tube has a length longer than the welded and sealed portion of the closing body, and extends to the outside from the welded and sealed portion of the closing body .
[0016]
The invention according to claim 5 is characterized in that the concentration of the conductive inorganic substance component at the outer end of the welded sealed portion where the closed tube is welded and sealed is 0% by volume or more and 3% by volume or less. It is set as the obstruction body of Claim 1 or Claim 2.
[0017]
[Action]
A portion from the outer end of the welded sealing part where the closed tube is welded and sealed to the outer periphery of the welded sealed part where the sealed pipe is welded and sealed. When the closed body has a stepped outer peripheral surface so that the outer diameter is smaller than the outer diameter of the welded sealed part , the sharpness of the edge angle of the edge part formed at the outer end of the welded sealed part is reduced. Therefore, the mechanical strength of the edge portion of the closed body against the stress applied to the tube increases, and the mechanical strength of the tube also increases.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. The manufacturing method of the functionally gradient material constituting the closing body of the present invention is roughly as follows.
Prepare multiple types of mixed powders with different mixing ratios of insulating inorganic material component powder and conductive inorganic material component powder, mix with solvent containing organic binder, and then granulate insulating inorganic material component powder and A uniform composition layer is laminated at each mixing ratio with the conductive inorganic substance component powder and pressed to form a cylindrical shaped body.
[0019]
FIG. 9 shows a pressurizing method for molding a functionally gradient material. On the upper surface of the bottom member 22 of the mold 20 having a cylindrical molding space, the mixed powder having the lowest conductive inorganic substance component concentration is layered. Then, the mixed powder of the second lowest conductive inorganic substance component concentration is filled in layers, and the mixed powder in which the conductive inorganic substance component concentrations are changed in that order is filled in the required number of layers in layers, Thereafter, the molded body is formed by pressing with the pressure body 21 to form a molded layer laminate 23 in which a plurality of layers are integrally laminated. FIG. 9 shows a state of five layers. Thereafter, preliminary sintering is performed to remove the organic binder.
[0020]
After pre-sintering, a hole for inserting an electrode core rod having the same diameter as that of the electrode core rod extending from the end surface to the conductive portion of the closing body is processed at the approximate center of the insulating side end surface of the molded layer laminate 23. .
[0021]
Next, in the present invention, the outer peripheral surface continuous to the outer end of the welded sealed portion of the closed body to which the closed tube is welded and sealed is shaved by using a lathe, or the closed body is sealed with the lathe. Sharpen the outer peripheral surface of the unstoppable part. Then, after the electrode core rod is inserted into the hole for inserting the electrode core rod, the main sintering is performed.
[0022]
In the case of an incandescent lamp such as a halogen lamp shown in FIG. 11, the internal lead bar 16 is inserted into the hole of the closing body in place of the electrode core bar 6 to perform the main sintering.
[0023]
In addition, as a method of making the closure body of the present invention, for example, as shown in FIG. 10, the closure body shape after completion (a shape in which the diameter of the non-welded portion of the closure body is smaller than the diameter of the sealed portion to be welded ) is used. A uniform layer laminate in which a plurality of layers each having a uniform composition are integrally laminated may be formed using the inner surface-shaped mold 20.
[0024]
The completed closed body is welded and sealed to the closed tube portion of the discharge lamp with a flame burner such as an oxyhydrogen burner.
[0025]
【Example】
Next, examples of the present invention will be specifically described.
As the functionally gradient material, silica (SiO ₂ ) was used as the insulating inorganic substance component, and molybdenum (Mo) was used as the conductive inorganic substance component.
Prepare a molybdenum powder with an average particle size of 1.0 μm and a silica powder with an average particle size of 5.6 μm, prepare a mixed powder with different volume ratios of silica, and mix the mixed powder with stearic acid to granulate 9 are stacked in the order of increasing volume ratio of silica in the mold 20 shown in FIG. 9, and compressed in the axial direction with a load of 1.5 t / cm ² by the pressurizing body 21 to form a cylindrical molded layer laminate. 23 was obtained. And the molding layer laminated body 23 was temporarily sintered at 1200 degreeC in hydrogen gas for 30 minutes, and the organic binder was removed.
[0026]
After pre-sintering, a hole for inserting an electrode core rod was formed on the silica side end face of the functionally graded material closing body. And the outer peripheral surface which continues to the to- be-welded sealing part outer end of a closure body was shaved and grooved using the lathe. As for the dimensions of the functionally gradient material closing body, the total length in the axial direction is 12 mm and the outer diameter in the radial direction is 2.1 mm. The appropriate depth of the groove is 0.1 to 0.5 mm. In this embodiment, the depth is 0.2 to 0.3 mm. The location of the grooved portion was 5 mm from the end surface on the silica side. If the molybdenum concentration of the functionally gradient material is too high, the closed body will crack when sealed with the closed tube, so the groove position depends on the axial molybdenum concentration distribution determined during the design of functionally graded material manufacturing. To do.
[0027]
Next, a main sintering process was performed in which a tungsten electrode core rod was inserted into the hole for inserting the electrode core rod and heated at 1820 ° C. for 5 minutes in a vacuum atmosphere to shrink-fit the electrode core rod.
[0028]
When welding a functionally gradient material closure body with a closure tube, it is welded at the insulating portion of the closure body, but from the relationship of the thermal expansion coefficient of the portion of the closure body that is welded with silica as the closure tube material, conventionally, Up to a region where the molybdenum concentration of the functionally gradient material was 0% to 1.7% by volume was regarded as a region where welding and sealing with a closed tube were possible.
However, as a result of intensive studies by the inventors, it has been confirmed that the molybdenum concentration of the functionally gradient material exceeds 1.7% by volume and reaches 3% without being cracked in the closed body and can be welded to the closed tube. That is, the closing body can be sealed in the closing tube in a molybdenum concentration range of 0 to 3 wt%, the width of the sealing region can be made relatively wide, and a more airtight sealing can be achieved.
[0029]
FIG. 2 is a sectional view of a discharge lamp in which a conventionally used cylindrically-structured functionally graded material closing body is used for sealing the closing tube, and the closing tube is longer than the welded and sealed portion of the closing body. The outer diameter A of the welded and sealed portion is equal to the outer diameter B of the portion that is not welded and sealed (A = B). On the other hand, FIGS. 4 to 8 and FIG. 11 are partial sectional views showing an embodiment in which the tube closure of the present invention is applied to a discharge lamp. C in FIG. 6 is the outer diameter of the groove. In the example of FIG. 4, A> B, A = B and A> C in the example of FIG. 6, and A>B> C in the example of FIG.
In the example of FIG. 8, the tapered portion 14 is formed on the side of the closing body facing the light emission space, and the gas pressure resistance in the arc tube is increased. The taper portion was formed by turning the closing body on a lathe and cutting with a blade of a cemented carbide tool obliquely from the closing body.
FIG. 11 shows an example in which the closure of the present invention is used in a halogen lamp as an incandescent lamp.
[0030]
Next, the functionally gradient material occlusion body of the present invention, the discharge lamp as the tube of the present invention using the occlusion body, the conventional cylindrical gradient functional material occlusion body, and the discharge lamp using the occlusion body are actually used. The results of investigating the percentage of damage at the time of production are described.
A discharge lamp using the closure of the present invention has the shape shown in FIG. 4, and a conventional discharge lamp using the closure has the shape shown in FIG.
[0031]
The dimensions of the closure used for the manufactured discharge lamp are as follows.

[0032]
The prepared closed bodies were 50 conventional products and 100 products of the present invention, and discharge lamps were manufactured using the respective closed bodies for comparison.
When a conventional closure is used as a closure for a discharge lamp, 10 of the 50 discharge lamps are edge portions at the outer end of the sealed part to be welded in the process of welding and sealing the closure and the closure tube. It broke and was damaged. Further, of the 40 pieces remaining in the welding and sealing process, 5 pieces were damaged during the lamp assembly manufacturing for attaching the base. That is, 15 out of 50 were damaged.
[0033]
On the other hand, when the closure body of the present invention was used as a discharge lamp closure body, it was 0 that the closure body was broken and damaged in 100 discharge lamps in the process of welding and sealing the closure body and the closure tube. Only one lamp was damaged during the assembly of the lamp assembly. That is, only one of the 100 was damaged.
As described above, the groove portion is formed on the outer peripheral surface continuously to the outer end of the sealed portion to be welded , so that it is apparently broken and broken at the closed tube portion in the tube sealing step and the assembly manufacturing step after the sealing step. It can be seen that a tube with few things can be obtained.
[0034]
This invention is to be welded seal portion outer end as shown the groove 13 on the outer peripheral surface continuous with the edge portion 12 which is an object to be welded seal portion outer end, or in FIG. 4 as in FIG. 6 Edge Since the small-diameter portion is formed from the portion 12 to the conductive portion 41, the angle (θ) formed between the outer end of the sealed portion to be welded and the outer surface of the closed body is large as shown in FIG. This is because there is no sharp edge as shown in FIG.
[0035]
In the description of the above embodiment, the functionally gradient material made of a combination of silica and molybdenum has been described. However, the insulating inorganic substance component includes alumina, zirconia, magnesia, silicon carbide, silicon nitride, titanium carbide, and the like. It can be used as a practical material, and as the conductive inorganic substance component, nickel, tungsten, tantalum, chromium, platinum, or the like can be used as a practical material.
[0036]
Further, the shape of the closing body is not limited to the cylindrical shape, and may be a prismatic body having a polygonal cross section perpendicular to the axis. However, in the case of a polygonal prismatic body, not the outer diameter but the maximum cross-sectional dimension is smaller in the portion that is not welded and sealed than the welded and sealed portion.
[0037]
【The invention's effect】
As described in detail above, the use of the tube closure according to the invention of claim 1 reduces the sharpness of the angle at the outer edge of the welded sealed portion of the closed tube and reduces the manufacturing process of the lamp. It is possible to obtain a tube that does not break and break the lamp.
[0038]
By using the tube closing body according to the second aspect of the present invention, the outer diameter of the non-welded portion of the closing body is small, so that it does not come into contact with the inner diameter of the closing tube, and the tube is more resistant to breakage.
[0039]
In the tube according to the invention of claim 3, since the closing body forms a groove portion on the outer peripheral surface continuous to the outer end of the welded sealed portion , the sharpness of the edge portion of the welded sealed portion is eliminated, and the edge Since the mechanical strength of the portion is increased, it is difficult to break, and the closed tube also covers the entire closed body and functions sufficiently as a protective tube.
[0040]
Bulb according a fourth aspect of the present invention, as the closure tube is smaller than the outer diameter of the welded sealing parts of the outer diameter of the portion ranging outward from the welding sealing portion outer end of the closure to be sealed welded seal Since there is a step on the outer peripheral surface, the sharpness of the edge of the welded sealed part is eliminated, the mechanical strength of the edge is increased, it is difficult to break, and the closing tube covers the entire closing body Functions sufficiently as a protective tube.
[0041]
According to the invention of claim 5, it is possible to seal the functionally graded material closing body to the closing tube in the range of molybdenum concentration from 0 to 3 wt%, and it is possible to make the welded sealing area wider and more airtight than before. Can be welded and sealed.
[Brief description of the drawings]
FIG. 1 shows a partial cross-sectional view of an example of a conventional discharge lamp using a functionally gradient material as a closure for a discharge lamp.
FIG. 2 is a partial sectional view of a discharge lamp using a conventional functionally graded material closure body.
3 is an enlarged view of an edge portion of a partial cross-sectional view of the discharge lamp shown in FIG.
FIG. 4 is a partial cross-sectional view of an embodiment in which a functionally graded material closure body according to the present invention is applied to a discharge lamp.
5 is an enlarged view of an edge portion of the partial cross-sectional view of the discharge lamp shown in FIG.
FIG. 6 is a partial cross-sectional view of another embodiment of a functionally graded material closing member and a discharge lamp using the same according to the present invention.
FIG. 7 shows a partial cross-sectional view of another embodiment of a functionally graded material closing body and a discharge lamp using the same according to the present invention.
FIG. 8 is a partial cross-sectional view of another embodiment of a functionally graded material closing body and a discharge lamp using the same according to the present invention.
FIG. 9 shows a diagram of a general pressurizing method when molding a functionally graded material closure body.
FIG. 10 is a diagram of a pressurizing method as an example when molding a functionally gradient material obstruction of the present invention.
FIG. 11 shows a cross-sectional view of a functionally gradient material obturator of the present invention and an incandescent bulb using the same.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Discharge lamp 2 Light-emitting tube 3 Closure tube 4 Closure body 5 Electrode 6 Electrode core rod 7 External lead rod 8 Welding portion 9 External lead rod extension wire 10 Base 11 Brazing portion 12 Edge portion 13 Groove portion 14 Taper portion 15 Filament 16 Internal lead Rod 17 Adhesive 20 Mold 21 Pressurizing body 22 Bottom member 23 Molded layer laminate 40 Insulating part 41 Conductive part A Outer diameter B of the sealing body to be welded and sealed Outside the part of the sealing body that is not welded and sealed Diameter C Outer diameter of the groove of the closure

Claims

A tube bulb closure for sealing a tube closed to a tube arc tube,
A substantially column-shaped functionally gradient material comprising a conductive inorganic substance component and an insulating inorganic substance component, wherein the conductive portion and the insulating portion are formed by changing the concentration of the conductive inorganic substance component in an inclined direction along the axial direction. Consists of
In addition, the tube closure is characterized in that a groove portion is formed on the outer peripheral surface continuously to the outer end of the sealed portion to be welded and sealed .

A tube bulb closure for sealing a tube closed to a tube arc tube,
A substantially column-shaped functionally gradient material comprising a conductive inorganic substance component and an insulating inorganic substance component, wherein the conductive portion and the insulating portion are formed by changing the concentration of the conductive inorganic substance component in an inclined direction along the axial direction. Consists of
In addition, the outer peripheral surface is stepped so that the outer diameter of the portion from the outer end of the welded sealed portion where the closed tube is welded and sealed is smaller than the outer diameter of the welded sealed portion. A tube closure.

In a tube having an arc tube, an occlusion tube connected to the arc tube, and an occlusion body that occludes the occlusion tube,
The closed body is composed of a conductive inorganic substance component and an insulating inorganic substance component, and is formed by forming a conductive portion and an insulating portion by changing the concentration of the conductive inorganic substance component in an inclined direction along the axial direction. Consists of columnar functionally graded materials,
And the groove part is formed in the outer peripheral surface continuously to the welded sealed part outer end where the closed tube is welded and sealed,
The tube characterized in that the closed tube has a longer length than the welded and sealed portion of the closed body, and extends outward from the welded and sealed portion of the closed body .

In a tube having an arc tube, an occlusion tube connected to the arc tube, and an occlusion body that occludes the occlusion tube,
The closed body is composed of a conductive inorganic substance component and an insulating inorganic substance component, and is formed by forming a conductive portion and an insulating portion by changing the concentration of the conductive inorganic substance component in an inclined direction along the axial direction. Consists of columnar functionally graded materials,
And a step is attached to the outer peripheral surface so that the outer diameter of the part from the outer end of the welded sealed part to which the closed tube is welded and sealed is smaller than the outer diameter of the welded sealed part ,
The tube characterized in that the closed tube has a longer length than the welded and sealed portion of the closed body, and extends outward from the welded and sealed portion of the closed body .

The blockage according to claim 1 or 2, wherein the concentration of the conductive inorganic substance component at the outer end of the sealed portion to be welded and sealed with the closed tube is 0% by volume or more and 3% by volume or less. body.