JP2005026146A - High pressure metal vapor discharge lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent failures of a non-linear ferroelectric ceramic capacitor by decreasing a stress against the non-linear ferroelectric ceramic capacitor which is a starter in the lamp even in the case the lamp is surely re-started and frequent lighting and putting out of the light are carried out. <P>SOLUTION: In a high pressure metal vapor discharge lamp in which a start-assisting circuit including a non-linear ferroelectric ceramic capacitor is connected in parallel to the light emitting tube which has electrodes at both ends and in which a light-emitting metal is sealed in the inner part together with a start-assisting rare gas, and in which a thermal responding switch is connected to the non-linear ferroelectric ceramic capacitor in series, the operating temperature of the thermal responding switch is set to 50-80°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００２４】
ところで、図５はランプ消灯後の時間と、それぞれの位置における非線形強誘電体セラミックコンデンサが発生するパルス電圧の関係である。
非線形強誘電体セラミックコンデンサに不具合が生じないようにするためには、非線形強誘電体セラミックコンデンサの温度が７５℃以下になってからパルスを発生させるよう設計するのが良い。そこで、表１の値を図５にプロットする事により、発光管中心から非線形強誘電体セラミックコンデンサの発光管側端部の距離に関係なく、パルス電圧は７００〜８００Ｖ以上必要であることが分かる。
ここで非線形強誘電体セラミックコンデンサは、温度が７５℃の時に７００〜８００Ｖのパルス電圧を発生するといえる。これは非線形強誘電体セラミックコンデンサが温度に依存して発生するパルス電圧を変化させるからである。
【００２５】
図３は、ランプ消灯後にランプが再始動するために必要なパルス電圧を時間と共に測定したグラフである。上記の理由より、非線形強誘電体セラミックコンデンサが出力するパルス電圧が７００〜８００Ｖで再始動するためには、発光管が必要とするパルス電圧が７００〜８００Ｖ以下になる必要があり、図３より、ランプ消灯後９分経過してからであるとわかる。
【００２６】
次に図１に示した実施の形態と同様に構成した４００Ｗの非線形強誘電体セラミックコンデンサ内蔵メタルハライドランプにおいて、熱応動スイッチの動作温度とランプ消灯後に熱応動スイッチが閉の状態となる時間の関係を測定したところ、熱応動スイッチは発光管との距離は関係なく図６に示すような結果が得られた。なお、点灯姿勢垂直とし、低格電源電圧の条件にて、室温２５℃、無風状態で３０分点灯後消灯して行った。
【００２７】
上記の理由から消灯後９分経ってから非線形強誘電体セラミックコンデンサが動作をすると、非線形強誘電体セラミックコンデンサに不具合が生じないので、図６より熱応動スイッチの動作温度は８０℃以下にするのが良い。しかし熱応動スイッチの動作温度を常温近くにしてしまうと、熱応動スイッチは常温で誤動作してしまう可能性もあり、ランプが不点になる可能性がある。また一般的にメタルハライドランプの再始動時間は１５分未満が推奨されているので、図６より熱応動スイッチの動作温度は５０〜８０℃となるように設定しなければならない。
【００２８】
以上のことからランプが確実に再始動し、なおかつ頻繁に点灯・消灯を行った場合でも、ランプ内始動器である非線形強誘電体セラミックコンデンサにかかるストレスを減少させて、非線形強誘電体セラミックコンデンサの不具合が生じるのを防止するためには、前記熱応動スイッチの動作温度が５０〜８０℃となるように設定しなければならない。
【００２９】
ところで表１と図６より、以下のことも考えられる。
発光管中心から非線形強誘電体セラミックコンデンサの発光管側端部までの距離が６５ｍｍのとき、表１よりランプ消灯後１４分以上経ってから動作を開始しないと、非線形強誘電体セラミックコンデンサに不具合が生じてしまう事がわかるので、図６より熱応動スイッチの動作温度は５０℃以下にする必要がある。
同様に発光管中心から非線形強誘電体セラミックコンデンサの発光管側端部までの距離が７５〜１０５ｍｍのとき８０℃以下、
発光管中心から非線形強誘電体セラミックコンデンサの発光管側端部までの距離が１１５ｍｍのとき６５℃以下にする必要がある。
ところで一般的にメタルハライドランプの再始動時間は１５分未満が推奨されているので、発光管中心から非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙ（ｍｍ）と熱応動スイッチの動作温度の関係は表２のようになる。
【００３０】
【表２】

【００３１】
以上のことからランプが確実に再始動し、なおかつ頻繁に点灯・消灯を行った場合でも、ランプ内始動器である非線形強誘電体セラミックコンデンサにかかるストレスを減少させて、非線形強誘電体セラミックコンデンサの不具合を防止するためには、通常は熱応動スイッチの動作温度を５０〜８０℃とするが、非線形強誘電体セラミックコンデンサが発光管から近い場合は、熱応動スイッチの動作温度を５０℃、発光管から遠い場合は熱応動スイッチの動作温度を５０〜６５℃とする必要がある。
【００３２】
このように、発光管からの距離が近い場合と遠い場合とで、同様な傾向を示すのは、ほとんど前記非線形強誘電体セラミックコンデンサの支柱部材の影響ではなく、ランプ外球内に封入されている不活性ガスの対流態様による温度分布の不均一性によるものと考えられる。すなわち、発光管の中心より離れすぎた部分においては、不活性ガスの対流が円滑に行われず、高温の不活性ガスがよどんで温度の低下が阻害されたためと考えられる。
【００３３】
次に、図１で示した実施の形態と同様に構成した４００Ｗの非線形強誘電体セラミックコンデンサ内蔵メタルハライドランプにおいて、熱応動スイッチの動作温度を５０〜１２０℃まで変えて、なおかつ発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙを６５（ｍｍ）から１１５（ｍｍ）まで変えたランプを多数製作し、ランプの再始動と非線形強誘電体セラミックコンデンサの不具合の状態の有無を調べた。ここで熱応動スイッチの動作温度を５０℃以上としたのは、４０℃程度では常温で動作してしまうため４０℃以下は省いた。結果を表３に示す。
【００３４】
【表３】

【００３５】
表中の○は熱応動スイッチが閉の状態となった直後に、全数ランプが再始動した、なおかつ非線形強誘電体セラミックコンデンサに不具合が生じなかったことを示し、表中の×は熱応動スイッチが閉の状態となった直後に、１本でもランプが再始動しないもしくは非線形強誘電体セラミックコンデンサに不具合が生じた事を示す。なお、ランプの各部構成は図８で示したものと同じであり、点灯姿勢を垂直とし、定格電源電圧にて、室温２５℃、無風状態で３０分点灯後消灯して行った。
【００３６】
表３に示すとおり、先の実験結果である前記熱応動スイッチの動作温度が５０〜８０℃となるように設定して、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙが７５〜１０５（ｍｍ）となるように設定したランプは全数ランプが確実に再始動し、なおかつ非線形強誘電体セラミックコンデンサに不具合は生じなかった。
つづいて、図１で示した実施の形態と同様に構成した２５０Ｗの非線形強誘電体セラミックコンデンサ内蔵メタルハライドランプにおいて、上記と同様な実験を行った。結果を表４に示す。
【００３７】
【表４】

【００３８】
表４に示すとおり、先の実験結果である前記熱応動スイッチの動作温度が５０〜８０℃となるように設定して、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙが６５〜１００（ｍｍ）となるように設定したランプは全数ランプが確実に再始動し、なおかつ非線形強誘電体セラミックコンデンサの不具合は生じなかった。
更に、図１で示した実施の形態と同様に構成した１０００Ｗの非線形強誘電体セラミックコンデンサ内蔵メタルハライドランプにおいて、上記と同様な実験を行った。結果を表５に示す。
【００３９】
【表５】

【００４０】
表５に示すとおり、先の実験結果である前記熱応動スイッチの動作温度が５０〜８０℃となるように設定して、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙが１０５〜１３５（ｍｍ）となるように設定したランプは全数ランプが確実に再始動し、なおかつ非線形強誘電体セラミックコンデンサの不具合は生じなかった。
【００４１】
図７は表３乃至表５をまとめたグラフであり、再始動時に非線形強誘電体セラミックコンデンサに不具合が生じない範囲を示す。図７に記載してある式は近似曲線であり、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙ（ｍｍ）の値は小数点以下を四捨五入し、ランプ電力をＸ（Ｗ）として、
０．０５Ｘ＋５３≦Ｙ≦０．０５Ｘ＋８７
の範囲となる。この範囲内であれば、ランプが確実に再始動し、なおかつ頻繁に再始動を行った場合でも、ランプ内始動器である非線形強誘電体セラミックコンデンサにかかるストレスを減少させて、非線形強誘電体セラミックコンデンサの不具合を防止することが可能である。
【００４２】
次に、図８で示した実施の形態と同様に構成した４００Ｗの非線形強誘電体セラミックコンデンサ内蔵メタルハライドランプにおいて、上記実験の中で判明した条件である、熱応動スイッチの動作温度を５０〜８０℃および発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙが７５〜１０５（ｍｍ）に対し、再始動に関して条件の厳しい場合となるように、熱応動スイッチの動作温度を８０℃、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離Ｙを７５（ｍｍ）としたランプを多数作成し、再始動を再現させるため４５分点灯後消灯して、その後１分間電源を遮断し、その後再び４５分電源供給を行う点滅テストを行った。なお、ランプの各部構成は図８で示したものと同じであり、点灯姿勢を垂直とし、定格電源電圧にて、室温２５℃、無風状態で行った。上記のように再始動を再現させた点滅テストを５０００回以上行っても、ランプは正常に再始動し、かつ非線形強誘電体セラミックコンデンサに不具合は生じなかった。
【００４３】
【発明の効果】
以上のように本発明の上記のように構成された両端に電極を有し、内部に始動補助希ガスと共に発光金属を封入してなる発光管に、非線形強誘電体セラミックコンデンサを含む始動補助回路を並列に接続し、前記非線形強誘電体セラミックコンデンサと直列に熱応動スイッチを接続し、不活性ガスを封入する外管内に収納してなる高圧金属蒸気放電灯において、前記熱応動スイッチの動作温度が５０〜８０℃となるように設定する。
さらに、発光管中心から前記非線形強誘電体セラミックコンデンサの発光管側端部までの距離をＹ（ｍｍ）とし、ランプ電力をＸ（Ｗ）としたとき、
０．０５Ｘ＋５３≦Ｙ≦０．０５Ｘ＋８７
を満足するように設定することにより、ランプ消灯後直ちに点灯した場合、ランプが確実に再始動し、また頻繁に点灯・消灯を行った場合でも、ランプ内始動器である非線形強誘電体セラミックコンデンサに上記粒界と空隙に加わるストレスと上記整流現象によって流れる瞬間的な電流によるストレスを減少させて、非線形強誘電体セラミックコンデンサの不具合が生じるのを防止する事ができる。
【図面の簡単な説明】
【図１】本発明に係わるランプ内の始動器として非線形強誘電体セラミックコンデンサを含む始動補助回路を用いたメタルハライドランプの実施の形態を示す平面図である。
【図２】再始動時に非線形強誘電体セラミックコンデンサが動作したときの温度と、非線形強誘電体セラミックコンデンサの不具合の関係を示す図である。
【図３】ランプ消灯時間と消灯後にランプが再始動するために必要なパルス電圧の関係を示す図である。
【図４】ランプ消灯時間とランプ消灯後の非線形強誘電体セラミックコンデンサの温度の関係を示す図である。
【図５】ランプ消灯時間とランプ消灯後の非線形強誘電体セラミックコンデンサが発生するパルス電圧の関係を示す図である。
【図６】熱応動スイッチの動作温度とランプ消灯後に熱応動スイッチが閉の状態となる時間の関係を示す図である。
【図７】ランプ電力と、発光管中心からの非線形強誘電体セラミックコンデンサの距離を示し、非線形強誘電体セラミックコンデンサに不具合が生じないような範囲を示す図である。
【図８】従来のランプ内の始動器として非線形強誘電体セラミックコンデンサを含む始動補助回路を用いた従来のメタルハライドランプの回路図である。
【符号の説明】
１、２１：発光管
２、２２：非線形強誘電体セラミックコンデンサ
３、２３：非線形強誘電体セラミックコンデンサに並列に接続された抵抗
４、２４：半導体スイッチ
５、２５：半導体スイッチに並列に接続された抵抗
６、２６：外球
７ａ、２７ａ：主電極
７ｂ、２７ｂ：主電極
８、２８：補助電極
９、２９：始動補助抵抗
１０、３０：熱応動スイッチ
１１：口金[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a high-pressure metal vapor discharge lamp, and to an improvement of a high-pressure metal vapor discharge lamp using a starting auxiliary circuit including a nonlinear ferroelectric ceramic capacitor as a starter in the lamp.
[0002]
[Prior art]
FIG. 8 is a circuit diagram of a conventional metal halide lamp using a starting auxiliary circuit including a nonlinear ferroelectric ceramic capacitor as a starter in the lamp, and is proposed in Japanese Patent Laid-Open No. 08-096977.
[0003]
[Patent Document 1]
JP 08-096977
[0004]
In the figure, reference numeral 21 denotes an arc tube having electrodes at both ends, in which a luminescent metal is enclosed together with a starting auxiliary rare gas, 22 is a nonlinear ferroelectric ceramic capacitor, and 23 is in parallel with the nonlinear ferroelectric ceramic capacitor 22. A resistor for discharging the charge accumulated in the nonlinear ferroelectric ceramic capacitor 22 when the temperature of the connected nonlinear ferroelectric ceramic capacitor rises and exceeds the Curie temperature after the lamp is lit, 24 is a semiconductor switch, 25 is The resistor is connected in parallel to the semiconductor switch 4 and stabilizes the ON phase of the semiconductor switch 24.
[0005]
A starter in the lamp is constituted by a series circuit of the nonlinear ferroelectric ceramic capacitor 22 and the semiconductor switch 24, and the nonlinear ferroelectric ceramic capacitor 22 is stored in the outer bulb 26 connected in parallel with the arc tube 21. The semiconductor switch 24 is disposed in a base portion fixed to the end of the outer sphere 26. The arc tube 21 has main electrodes 27a and 27b sealed at both ends, an auxiliary electrode 28 is sealed in the vicinity of at least one of the main electrodes 27a, and a light-emitting metal is sealed inside together with a starting auxiliary rare gas. . Further, a starting auxiliary resistor 29 and a thermally responsive switch 30 having a normal temperature closed contact are connected in series between the auxiliary electrode 28 and the main electrode 27b.
[0006]
The lamp configured as described above is connected to an AC power source via a ballast and is lit. When the lamp starts, the thermoresponsive switch, which is a closed contact at room temperature, is opened by the radiant heat of the arc tube, and a high voltage pulse is used to disconnect the nonlinear ferroelectric ceramic capacitor and the semiconductor switch placed in series with the thermoresponsive switch from the power supply. Occurrence stops.
[0007]
In addition, when the power supply voltage is cut off and the lamp is turned off, the lamp is turned on because the radiant heat of the arc tube disappears at the time of restart after supplying the power supply voltage and waiting for the lamp to turn on again. Some of the thermal responsive switches that are open will gradually return to the closed state as the temperature of the thermal responsive switch decreases. The lamp will not restart if it is fully closed and the necessary pulse voltage does not occur upon restart.
[0008]
[Problems to be solved by the invention]
In the metal halide lamp having the in-lamp starter, a rectification phenomenon occurs during the transition from the glow discharge to the arc discharge when the lamp is started and restarted. A current of about (A) to 30 (A) flows instantaneously. Since the nonlinear ferroelectric ceramic capacitor installed in the outer tube as a starter is installed electrically in parallel with the arc tube, the current due to the rectification phenomenon is instantaneously applied to the nonlinear ferroelectric ceramic capacitor. The stress due to this current is applied to the nonlinear ferroelectric ceramic capacitor which is the starter in the lamp.
[0009]
If the nonlinear ferroelectric ceramic capacitor is installed in a place where the temperature due to the radiant heat of the arc tube is high when the lamp is lit, the nonlinear ferroelectric ceramic capacitor generates a pulse when the lamp is restarted, that is, the nonlinear ferroelectric ceramic. When the capacitor operates, the nonlinear ferroelectric ceramic capacitor is not sufficiently cooled. When the nonlinear ferroelectric ceramic capacitor operates in such a state, the pulse voltage generated by the nonlinear ferroelectric ceramic capacitor is low, so that the lamp does not restart immediately after the nonlinear ferroelectric ceramic capacitor generates the pulse voltage. There may be several minutes after the nonlinear ferroelectric ceramic capacitor generates the pulse voltage until the lamp actually restarts. During this time, the nonlinear ferroelectric ceramic capacitor continues to generate a pulse voltage, and a phenomenon occurs in which the arc discharge is caused between the main electrodes inside the arc tube many times. That is, the current due to the rectification phenomenon flows through the nonlinear ferroelectric ceramic capacitor several times.
[0010]
On the other hand, even when the nonlinear ferroelectric ceramic capacitor is placed regardless of the distance from the center of the arc tube, at the time of restarting, the thermal responsive switch is turned on before the nonlinear ferroelectric ceramic capacitor drops to the temperature at which the pulse voltage is generated. In the closed state, the non-linear ferroelectric ceramic capacitor continues to be supplied with only the power supply voltage without generating a pulse, and the pulse voltage is generated after the temperature decreases to the temperature at which the non-linear ferroelectric ceramic capacitor generates the pulse voltage. To do. In this case, since the nonlinear ferroelectric ceramic capacitor is not sufficiently cooled, the pulse voltage generated by the nonlinear ferroelectric ceramic capacitor is low. Therefore, the lamp does not restart immediately after the nonlinear ferroelectric ceramic capacitor generates a pulse voltage.
Also, even if the lamp is designed to generate a pulse voltage at the same time that the nonlinear ferroelectric ceramic capacitor drops to a temperature that generates a pulse voltage, the nonlinear ferroelectric ceramic capacitor is not sufficiently cooled. The pulse voltage generated by the capacitor is low. Therefore, the lamp does not restart immediately after the nonlinear ferroelectric ceramic capacitor generates a pulse voltage, as in the above case. In either case, it may take several minutes after the nonlinear ferroelectric ceramic capacitor generates the pulse voltage until the lamp actually restarts. During this time, the nonlinear ferroelectric ceramic capacitor continues to generate a pulse voltage, and a phenomenon occurs in which the arc discharge is caused between the main electrodes inside the arc tube many times. That is, the current due to the rectification phenomenon flows through the nonlinear ferroelectric ceramic capacitor several times.
[0011]
As a result, when the lamp is frequently turned on and off, the nonlinear ferroelectric ceramic capacitor, which is the starter in the lamp, is stressed by the current flowing due to the rectification phenomenon that flows instantaneously. There was a risk that the ceramic capacitor might be damaged early.
The present invention has been made in order to solve the above-described problems. Even when the lamp is surely restarted and the lamp is frequently turned on and off, the nonlinear ferroelectric ceramic capacitor is a starter in the lamp. The purpose is to reduce the stress applied to the non-linear ferroelectric ceramic capacitor.
[0012]
[Means for Solving the Problems]
In order to solve the above problem, a starting auxiliary circuit including a non-linear ferroelectric ceramic capacitor is connected in parallel to an arc tube having electrodes at both ends and enclosing a luminescent metal together with a starting auxiliary rare gas inside, In a high-pressure metal vapor discharge lamp in which a thermally responsive switch is connected in series with a non-linear ferroelectric ceramic capacitor and housed in an outer tube filled with an inert gas, the operating temperature of the thermally responsive switch is 50 to 80 ° C. Set as follows.
[0013]
Furthermore, when the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is Y (mm) and the lamp power is X (W),
0.05X + 53 ≦ Y ≦ 0.05X + 87
Was set to satisfy.
[0014]
By satisfying the above, even if the lamp is turned off and turned on immediately, even if the lamp restarts reliably, and the lamp is turned on and off frequently, the nonlinear ferroelectric that is the starter in the lamp The stress applied to the grain boundaries and voids of the capacitor in the body ceramic capacitor and the stress due to the instantaneous current flowing due to the rectification phenomenon can be reduced, thereby preventing the malfunction of the nonlinear ferroelectric ceramic capacitor.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a plan view showing an embodiment of a metal halide lamp using a starting auxiliary circuit including a nonlinear ferroelectric ceramic capacitor as a starter in a lamp according to the present invention. This embodiment is a 400 W nonlinear ferroelectric. A metal halide lamp with a built-in ceramic capacitor is shown.
[0016]
In the figure, reference numeral 1 denotes an arc tube having electrodes at both ends, and a luminescent metal is enclosed in the inside together with a starting auxiliary rare gas, and 2 is a nonlinear ferroelectric ceramic capacitor, which is mainly composed of barium titanate (BaTiO ₃ ). A silver electrode film having a diameter of 16.0 (mm) is formed on both surfaces of a disk-shaped sintered body having a diameter of 18 (mm) and a thickness of 1.2 (mm), and electrode terminals are connected to the silver electrode films. The film is overcoated with inorganic glass and has a Curie temperature of about 90 ° C.
[0017]
3 discharges the electric charge accumulated in the nonlinear ferroelectric ceramic capacitor connected in parallel to the nonlinear ferroelectric ceramic capacitor 2 when the temperature of the nonlinear ferroelectric ceramic capacitor rises and exceeds the Curie temperature after the lamp is turned on. 4 is a semiconductor switch, and 5 is a resistor connected in parallel to the semiconductor switch 4 for stabilizing the ON phase of the semiconductor switch.
[0018]
Then, a starter in the lamp is constituted by a series circuit of the nonlinear ferroelectric ceramic capacitor 2 and the semiconductor switch 4, and is connected in parallel with the arc tube 1, and the nonlinear ferroelectric ceramic capacitor 2 encloses an inert gas. Housed in the outer sphere 6, the semiconductor switch 4 is disposed in the base 11 portion fixed to the end of the outer sphere 6. The arc tube 1 has main electrodes 7a and 7b sealed at both ends, an auxiliary electrode 8 is sealed in the vicinity of at least one of the main electrodes 7a, and a light emitting metal is sealed together with a starting auxiliary rare gas. . Further, a starting auxiliary resistor 9 and a thermally responsive switch 10 having a normal temperature closed contact are connected in series between the main electrode 7 b and the auxiliary electrode 8 so as to face the auxiliary electrode 8.
[0019]
First, the relationship between the temperature at which the nonlinear ferroelectric ceramic capacitor was activated during restart and the malfunction of the nonlinear ferroelectric ceramic capacitor was investigated. The experiment was performed by setting a nonlinear ferroelectric ceramic capacitor to each temperature atmosphere in an inert gas, and flowing a current similar to the rectification phenomenon that occurs when the lamp restarts, as shown in FIG. The result was obtained. As shown in FIG. 2, when the nonlinear ferroelectric ceramic capacitor is operated at a temperature higher than 75 ° C., the current due to the rectification phenomenon generated when the lamp is restarted causes a problem due to the stress applied to the nonlinear ferroelectric ceramic capacitor. Initially, the higher the temperature, the higher the probability of failure.
[0020]
Next, in a 400 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured in the same manner as the embodiment shown in FIG. 1, the pulse voltage necessary for restarting the lamp after extinguishing is set at the rated power supply voltage for a time. As a result, the results shown in FIG. 3 were obtained. Note that the measurement was performed with the lighting posture vertical, lighting at room temperature of 25 ° C. and no wind, and then turning off for 30 minutes.
[0021]
Next, in a 400 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured similarly to the embodiment shown in FIG. 1, the distance Y from the arc tube center to the arc tube side end portion of the nonlinear ferroelectric ceramic capacitor. 4 was prepared from 65 (mm) to 115 (mm), and the temperature change of the nonlinear ferroelectric ceramic capacitor after the lamp was extinguished and the generated pulse voltage were taken as the rated power supply voltage and measured with time. The results as shown in FIG. 5 were obtained. The measurement was performed with the lighting posture vertical, lighting at room temperature of 25 ° C. and no wind, and then turning off for 30 minutes. Here, the reason why the distance Y to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is limited to 65 (mm) to 115 (mm) is that it can be installed in the outer bulb of a 400 W lamp. is there.
[0022]
It can be seen from FIG. 2 that the failure of the nonlinear ferroelectric ceramic capacitor does not occur when the lamp is restarted when the temperature of the nonlinear ferroelectric ceramic capacitor becomes 75 ° C. or lower. As shown in FIG. 4, the temperature of the nonlinear ferroelectric ceramic capacitor at each position is 75 ° C. or less as shown in Table 1.
[0023]
[Table 1]

[0024]
FIG. 5 shows the relationship between the time after the lamp is extinguished and the pulse voltage generated by the nonlinear ferroelectric ceramic capacitor at each position.
In order to prevent a problem with the nonlinear ferroelectric ceramic capacitor, it is preferable to design the nonlinear ferroelectric ceramic capacitor so that a pulse is generated after the temperature of the nonlinear ferroelectric ceramic capacitor is 75 ° C. or lower. Therefore, by plotting the values in Table 1 in FIG. 5, it is understood that the pulse voltage needs to be 700 to 800 V or more regardless of the distance from the arc tube center to the arc tube side end portion of the nonlinear ferroelectric ceramic capacitor. .
Here, it can be said that the nonlinear ferroelectric ceramic capacitor generates a pulse voltage of 700 to 800 V when the temperature is 75 ° C. This is because the nonlinear ferroelectric ceramic capacitor changes the pulse voltage generated depending on the temperature.
[0025]
FIG. 3 is a graph in which the pulse voltage required for the lamp to restart after the lamp is turned off is measured with time. For the above reason, in order to restart the pulse voltage output from the nonlinear ferroelectric ceramic capacitor at 700 to 800 V, the pulse voltage required by the arc tube needs to be 700 to 800 V or less. It can be seen that 9 minutes have passed since the lamp was turned off.
[0026]
Next, in a 400 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured similarly to the embodiment shown in FIG. 1, the relationship between the operating temperature of the thermally responsive switch and the time that the thermally responsive switch is closed after the lamp is extinguished. As a result of the measurement, the result shown in FIG. 6 was obtained regardless of the distance between the thermoresponsive switch and the arc tube. In addition, it was set as the lighting attitude | position perpendicular | vertical, it turned on and turned off for 30 minutes by room temperature 25 degreeC and a windless condition on the conditions of the low-rated power supply voltage.
[0027]
For the above reason, if the non-linear ferroelectric ceramic capacitor starts operating after 9 minutes from extinguishing, the non-linear ferroelectric ceramic capacitor does not malfunction. Therefore, the operating temperature of the thermally responsive switch is set to 80 ° C. or less from FIG. Is good. However, if the operating temperature of the thermally responsive switch is brought to near room temperature, the thermally responsive switch may malfunction at room temperature, and the lamp may become unsatisfactory. In general, it is recommended that the restart time of the metal halide lamp is less than 15 minutes, so the operating temperature of the thermally responsive switch must be set to 50 to 80 ° C. from FIG.
[0028]
From the above, even if the lamp restarts reliably and is frequently turned on and off, the stress applied to the nonlinear ferroelectric ceramic capacitor that is the starter in the lamp is reduced, and the nonlinear ferroelectric ceramic capacitor In order to prevent this problem, the operating temperature of the thermally responsive switch must be set to 50 to 80 ° C.
[0029]
By the way, from Table 1 and FIG.
When the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is 65 mm, if the operation does not start more than 14 minutes after the lamp is extinguished, the nonlinear ferroelectric ceramic capacitor is defective. As shown in FIG. 6, the operating temperature of the thermally responsive switch needs to be 50 ° C. or lower.
Similarly, when the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is 75 to 105 mm,
When the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is 115 mm, it is necessary to set the temperature to 65 ° C. or lower.
By the way, since it is generally recommended that the restart time of the metal halide lamp is less than 15 minutes, the distance Y (mm) from the arc tube center to the arc tube side end portion of the nonlinear ferroelectric ceramic capacitor and the operation of the thermoresponsive switch Table 2 shows the temperature relationship.
[0030]
[Table 2]

[0031]
As a result, even when the lamp restarts reliably and is frequently turned on and off, the stress applied to the nonlinear ferroelectric ceramic capacitor that is the starter in the lamp is reduced, and the nonlinear ferroelectric ceramic capacitor is reduced. In order to prevent this problem, the operating temperature of the thermally responsive switch is normally set to 50 to 80 ° C. However, when the nonlinear ferroelectric ceramic capacitor is close to the arc tube, the operating temperature of the thermally responsive switch is set to 50 ° C. When it is far from the arc tube, it is necessary to set the operating temperature of the thermally responsive switch to 50 to 65 ° C.
[0032]
Thus, it is almost not the influence of the pillar member of the nonlinear ferroelectric ceramic capacitor that shows the same tendency when the distance from the arc tube is short and when it is far away, but it is enclosed in the outer bulb of the lamp. This is considered to be due to the non-uniformity of the temperature distribution due to the convection mode of the inert gas. That is, it is considered that the convection of the inert gas is not smoothly performed in the portion that is too far from the center of the arc tube, and the high temperature inert gas is stagnated to prevent the temperature from being lowered.
[0033]
Next, in a 400 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured in the same manner as the embodiment shown in FIG. 1, the operating temperature of the thermally responsive switch is changed from 50 to 120 ° C. and from the center of the arc tube. Many lamps were manufactured with the distance Y to the arc tube side end of the nonlinear ferroelectric ceramic capacitor changed from 65 (mm) to 115 (mm). The presence or absence of was investigated. The reason why the operating temperature of the thermally responsive switch is set to 50 ° C. or higher is that 40 ° C. or lower is omitted because it operates at room temperature at about 40 ° C. The results are shown in Table 3.
[0034]
[Table 3]

[0035]
○ in the table indicates that all lamps were restarted immediately after the thermal responsive switch was closed, and that no malfunction occurred in the nonlinear ferroelectric ceramic capacitor. Immediately after is closed, it indicates that even one of the lamps does not restart or a failure has occurred in the nonlinear ferroelectric ceramic capacitor. In addition, each part structure of a lamp | ramp is the same as what was shown in FIG. 8, the lighting attitude | position was made into perpendicular | vertical, it turned on and turned off for 30 minutes by the rated power supply voltage at room temperature of 25 degreeC, and a windless state.
[0036]
As shown in Table 3, the operating temperature of the thermally responsive switch, which is the result of the previous experiment, is set to be 50 to 80 ° C., from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor. All of the lamps set so that the distance Y of 75 to 105 (mm) was restarted reliably, and no problems were caused in the nonlinear ferroelectric ceramic capacitor.
Subsequently, an experiment similar to the above was performed on a 250 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured similarly to the embodiment shown in FIG. The results are shown in Table 4.
[0037]
[Table 4]

[0038]
As shown in Table 4, from the center of the arc tube to the arc tube side end of the nonlinear ferroelectric ceramic capacitor, the operating temperature of the thermal responsive switch, which is the result of the previous experiment, is set to 50 to 80 ° C. All of the lamps set so that the distance Y of 65 to 100 (mm) was restarted reliably, and the malfunction of the nonlinear ferroelectric ceramic capacitor did not occur.
Further, an experiment similar to that described above was conducted on a 1000 W nonlinear metal halide lamp with a built-in non-linear ferroelectric ceramic capacitor configured similarly to the embodiment shown in FIG. The results are shown in Table 5.
[0039]
[Table 5]

[0040]
As shown in Table 5, the operating temperature of the thermally responsive switch, which is the result of the previous experiment, is set to be 50 to 80 ° C., from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor. All of the lamps set so that the distance Y was 105 to 135 (mm) were reliably restarted, and there was no problem with the nonlinear ferroelectric ceramic capacitor.
[0041]
FIG. 7 is a graph summarizing Tables 3 to 5, and shows a range in which a defect does not occur in the nonlinear ferroelectric ceramic capacitor upon restart. The equation shown in FIG. 7 is an approximate curve, and the value of the distance Y (mm) from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is rounded off to the nearest decimal place. X (W)
0.05X + 53 ≦ Y ≦ 0.05X + 87
It becomes the range. If it is within this range, even if the lamp restarts reliably and frequently, the stress applied to the nonlinear ferroelectric ceramic capacitor that is the starter in the lamp is reduced, and the nonlinear ferroelectric material is reduced. It is possible to prevent problems with ceramic capacitors.
[0042]
Next, in the 400 W non-linear ferroelectric ceramic capacitor built-in metal halide lamp configured similarly to the embodiment shown in FIG. 8, the operating temperature of the thermally responsive switch, which is the condition found in the above experiment, is 50-80. The operation of the thermally responsive switch so that the conditions for restarting are severe when the temperature Y and the distance Y from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor are 75 to 105 (mm) A large number of lamps with a temperature Y of 80 ° C. and a distance Y from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor of 75 (mm) are created, and after 45 minutes of lighting, the lamp is turned off to reproduce the restart. Then, a flashing test was performed in which the power was shut off for 1 minute and then the power was supplied again for 45 minutes. In addition, each part structure of the lamp | ramp is the same as what was shown in FIG. 8, the lighting attitude | position was made into perpendicular | vertical, and it carried out with the rated power supply voltage, room temperature 25 degreeC, and the windless state. Even when the flashing test reproducing the restart as described above was performed 5000 times or more, the lamp restarted normally and no problem occurred in the nonlinear ferroelectric ceramic capacitor.
[0043]
【The invention's effect】
As described above, a starting auxiliary circuit including a nonlinear ferroelectric ceramic capacitor in an arc tube having electrodes at both ends configured as described above of the present invention and enclosing a light emitting metal together with a starting auxiliary rare gas. In a high pressure metal vapor discharge lamp that is connected in parallel, connected in series with the nonlinear ferroelectric ceramic capacitor, and housed in an outer tube enclosing an inert gas, the operating temperature of the thermal response switch Is set to 50 to 80 ° C.
Furthermore, when the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is Y (mm) and the lamp power is X (W),
0.05X + 53 ≦ Y ≦ 0.05X + 87
If the lamp is turned on immediately after the lamp is turned off, the nonlinear ferroelectric ceramic capacitor that is the starter in the lamp even if the lamp restarts reliably and frequently turns on and off. In addition, the stress applied to the grain boundaries and voids and the stress caused by the instantaneous current flowing due to the rectification phenomenon can be reduced, thereby preventing the occurrence of defects in the nonlinear ferroelectric ceramic capacitor.
[Brief description of the drawings]
FIG. 1 is a plan view showing an embodiment of a metal halide lamp using a start auxiliary circuit including a nonlinear ferroelectric ceramic capacitor as a starter in a lamp according to the present invention.
FIG. 2 is a diagram showing a relationship between a temperature when a nonlinear ferroelectric ceramic capacitor is operated at the time of restart and a defect of the nonlinear ferroelectric ceramic capacitor.
FIG. 3 is a diagram illustrating a relationship between a lamp turn-off time and a pulse voltage necessary for the lamp to restart after the lamp is turned off.
FIG. 4 is a graph showing the relationship between the lamp turn-off time and the temperature of the nonlinear ferroelectric ceramic capacitor after the lamp is turned off.
FIG. 5 is a diagram showing a relationship between a lamp turn-off time and a pulse voltage generated by a nonlinear ferroelectric ceramic capacitor after the lamp is turned off.
FIG. 6 is a diagram showing the relationship between the operating temperature of the thermal response switch and the time during which the thermal response switch is closed after the lamp is extinguished.
FIG. 7 is a diagram showing a lamp power and a distance of the nonlinear ferroelectric ceramic capacitor from the arc tube center, and showing a range in which a defect does not occur in the nonlinear ferroelectric ceramic capacitor.
FIG. 8 is a circuit diagram of a conventional metal halide lamp using a starting auxiliary circuit including a non-linear ferroelectric ceramic capacitor as a starter in a conventional lamp.
[Explanation of symbols]
1, 2: Arc tube 2, 22: Non-linear ferroelectric ceramic capacitor 3, 23: Resistor 4 connected in parallel to non-linear ferroelectric ceramic capacitor, 24: Semiconductor switch 5, 25: Connected in parallel to semiconductor switch Resistors 6, 26: outer sphere 7a, 27a: main electrode 7b, 27b: main electrode 8, 28: auxiliary electrode 9, 29: starting auxiliary resistor 10, 30: heat responsive switch 11: base

Claims (2)

A starting auxiliary circuit including a non-linear ferroelectric ceramic capacitor is connected in parallel to an arc tube having electrodes at both ends and enclosing a luminescent metal together with a starting auxiliary rare gas, and the non-linear ferroelectric ceramic capacitor and In a high-pressure metal vapor discharge lamp which is connected in series with a heat responsive switch and is housed in an outer tube filled with an inert gas, the operating temperature of the heat responsive switch is set to 50 to 80 ° C. High pressure metal vapor discharge lamp. When the distance from the arc tube center to the arc tube side end of the nonlinear ferroelectric ceramic capacitor is Y (mm) and the lamp power is X (W),
0.05X + 53 ≦ Y ≦ 0.05X + 87
The high-pressure metal vapor discharge lamp according to claim 1, wherein the high-pressure metal vapor discharge lamp is set to satisfy the following.

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