JPS60258844A - High pressure discharge lamp - Google Patents

Abstract

PURPOSE:To prevent generation of acoustic resonance phenomenon in high cycle lighting by making cross sectional shape in the major axial direction of luminous tube irregular polygon. CONSTITUTION:The cross sectional shape in the major axial direction of a luminous tube 1 is made irregular polygon. Then sound pressure of any position of the luminous tube 1 becomes constant and acoustic resonance phenomenon can be avoided without generation of stationary wave. Then, when such a high pressure discharge lamp lights in high cycle, curving, waving and going out of arc column, and break of the luminous tube generated by acoustic resonance penomenon can be prevented and stable lighting can be maintained.

Description

【発明の詳細な説明】 （技術分野） 本発明は高圧放電灯に関し、特に高圧放電灯の発光管の
形状に関する。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a high pressure discharge lamp, and more particularly to the shape of an arc tube of a high pressure discharge lamp.

（背景技術） 第１図は従来の高圧放電灯の一例を示し、石英等で形成
された発光管１の両端には電極２ａ、２ｂが対向して配
設され、該両電極２ａ、２ｂは封止部３ａ、３ｂに封入
されたモリブデン箔等の金属箔４ａ、４ｂに接続されて
いる。金属箔４ａ。(Background Art) FIG. 1 shows an example of a conventional high-pressure discharge lamp, in which electrodes 2a and 2b are arranged facing each other at both ends of an arc tube 1 made of quartz or the like. It is connected to metal foils 4a and 4b such as molybdenum foil sealed in the sealing parts 3a and 3b. Metal foil 4a.

４ｂは発光管１の支持も兼ねる支持導線５ａ、５ｂに接
続されており、発光管１は固定治ｐ、６　ａ　。4b is connected to support conductors 5a, 5b which also serve as supports for the arc tube 1, and the arc tube 1 is fixedly fixed.

６ｂを介して支持導線５ａ、５ｂに固定されている。支
持導線５ａ、５ｂは口金７を介して外部回路に接続され
る。また、発光管ｌ内には希ガス及び発光物質が適量封
入されており、発光管１を被う外管８内にはガスが封入
され、外管８の円囲には螢光体９が塗布されている。It is fixed to support conductors 5a and 5b via 6b. Support conductors 5a and 5b are connected to an external circuit via a base 7. Further, an appropriate amount of a rare gas and a luminescent substance are sealed in the arc tube 1, gas is sealed in an outer bulb 8 that covers the arc tube 1, and a phosphor 9 is surrounded by the outer bulb 8. It is coated.

かかる従来の高圧放電灯を高周波点灯すると、放電灯の
発光効率の向上、点灯回路の電子化による安定器の小型
・軽量化、低損失化という利点がある一方、特定の周波
数（発光管内の±１人物質等で決まる発光管内の音速と
、発光管形状で決まる共鳴周波数）で音響的共鳴現象が
生じ、アーク柱の属菌、揺らぎ、立ち消え、発光管の破
損等が発生するといった欠点がある。High-frequency lighting of such conventional high-pressure discharge lamps has the advantages of improving the luminous efficiency of the discharge lamp, making the ballast smaller and lighter due to electronic lighting circuits, and reducing loss. Acoustic resonance occurs due to the speed of sound inside the arc tube determined by the substance, etc., and the resonance frequency determined by the shape of the arc tube), which has disadvantages such as the occurrence of bacteria in the arc column, fluctuations, extinction, and damage to the arc tube. .

安定に点灯するためには、高圧放電灯が安定して点灯す
る領域で点灯させれば良いが、この安定領域はランプの
種類によって異なり、また、同種のランプでもランプご
とにばらつきがあるため、特定の点灯周波数を設定する
ことは難しい。In order to ensure stable lighting, a high-pressure discharge lamp should be lit in a stable lighting range, but this stable range varies depending on the type of lamp, and even among lamps of the same type, there are variations from lamp to lamp. It is difficult to set a specific lighting frequency.

また、　１ＱＱｋｌｌｚ以上の周波数での点灯、直流点
灯、矩形波点灯等により音響的共鳴現象を回避する方法
があるが、かかる点灯方法においては、回路構成の蝮雑
化や放射電波雑音の発４１Ｅ等の問題がある。In addition, there are methods to avoid the acoustic resonance phenomenon by lighting at a frequency of 1QQkllz or more, direct current lighting, square wave lighting, etc. However, such lighting methods may cause noise in the circuit configuration, generation of radiated radio noise, etc. There is a problem.

（発明の目的） 本発明は、上記欠点に鑑みてなされたもので、その目的
とするところは、高周波点灯した場合にも音響的共鳴現
象の生しない高圧放電灯を提供するにある。(Object of the Invention) The present invention was made in view of the above-mentioned drawbacks, and its object is to provide a high-pressure discharge lamp that does not cause acoustic resonance even when lit at high frequencies.

（発明の開示） 本発明は、発光管の長軸方向断面形状を各部で異ならせ
ることにより、音響的共鳴現象を回避したことを特徴と
する。(Disclosure of the Invention) The present invention is characterized in that the acoustic resonance phenomenon is avoided by making the longitudinal cross-sectional shape of the arc tube different at each part.

まず、音響的共鳴現象について説明する。音響的共鳴現
象は、発光管形状と封入物で決まる固有振動数と、入力
電力の時間的変化による発光管内の圧力変動とが一致し
た時に定在波が立つために生じる現象である。First, the acoustic resonance phenomenon will be explained. Acoustic resonance is a phenomenon that occurs when a standing wave is created when the natural frequency determined by the arc tube shape and the enclosed material matches the pressure fluctuation within the arc tube due to temporal changes in input power.

発光管内の封入物と発光管内の温度で決まる発ｌ　光管
内の音速をＣ８発光管長をし、発光管の半径をＲとし、
発光管を円筒と仮定し円筒座標系（ｒ、θ、ｚ）で共鳴
が起こる基本周波数Ｆを計算ず“　ると次式のようにな
り、 Ｚ方向共鳴：　Ｆ　ｚ　＝Ｃ／　（２Ｌ）θ方向共鳴：
Ｆθ−１．８４Ｃ／　（２πＲ）ｒ方向共鳴：　Ｆ　ｒ
　＝３．８３Ｃ／　（２πＲ）この基本周波数Ｆの整数
倍の周波数で共鳴が起こる。基本周波数Ｆの高さは、Ｆ
　２　＜　Ｆθ＜ｌ？ｒとなる。The light emission is determined by the inclusions in the arc tube and the temperature inside the arc tube.The speed of sound in the light tube is C8, the arc tube length is R, and the radius of the arc tube is R.
Assuming that the arc tube is a cylinder and not calculating the fundamental frequency F at which resonance occurs in the cylindrical coordinate system (r, θ, z), the following equation becomes, Z-direction resonance: F z = C/ (2L) θ Directional resonance:
Fθ-1.84C/ (2πR) r-direction resonance: F r
=3.83C/ (2πR) Resonance occurs at a frequency that is an integral multiple of this fundamental frequency F. The height of the fundamental frequency F is F
2 < Fθ < l? It becomes r.

高圧放電灯を高周波点灯する場合には、実用上可聴周波
数領域を避けなければならない。可聴周波数以上の周波
数で点灯した場合、２方向の高次モード共鳴は減衰して
しまい、音響的共鳴現象を起こすのはθ方向と「方向の
共鳴である。When lighting a high-pressure discharge lamp at high frequencies, it is practically necessary to avoid the audible frequency range. When the light is turned on at a frequency higher than the audible frequency, the high-order mode resonance in two directions is attenuated, and it is the resonance in the θ direction and the ``direction'' that causes the acoustic resonance phenomenon.

従来のように円筒形状の発光管を有する高圧放電灯に、
周波数がその発光管の共鳴周波数と同一の高周波電力を
印加した場合（ただし、可聴周波数以上）には、発光管
内の全部分でθ方向、ｒ方向の共鳴が起こり、その結果
化じた力が、アーク柱自体が有する安定に放電を持続さ
せようとする力に打ち勝ち、アーク柱が変形する。For high pressure discharge lamps with conventional cylindrical arc tubes,
When applying high-frequency power whose frequency is the same as the resonance frequency of the arc tube (however, it is higher than the audible frequency), resonance occurs in the θ and r directions in all parts of the arc tube, and the resulting force is , the arc column deforms, overcoming the force of the arc column itself to maintain stable discharge.

これに対して本発明に係る高圧放電灯、すなわち、第２
図に示すように断面形状が不等辺多角形の発光管１を有
する高圧放電灯の場合は、発光管断面内の任意の位置に
おける音圧が一定となるため、円筒形状の発光管の場合
に存在したθ方向、ｒ方向の共鳴現象は存在しなくなる
。In contrast, the high pressure discharge lamp according to the present invention, that is, the second
As shown in the figure, in the case of a high-pressure discharge lamp having an arc tube 1 with a scalene polygonal cross-section, the sound pressure at any position within the arc tube cross section is constant; The existing resonance phenomena in the θ direction and the r direction no longer exist.

次に、第３図は本発明の異なる実施例を示すもので、発
光管１の断面形状が不等辺多角形で、しかも発光管１を
形成する面同志がいずれも平行でないことを特徴とする
。このように構成することにより、発光管１内のどの位
置の音圧も一定値となり、定在波が生しず、音響的共鳴
現象を回避できる。Next, FIG. 3 shows a different embodiment of the present invention, in which the cross-sectional shape of the arc tube 1 is a scalene polygon, and the surfaces forming the arc tube 1 are not parallel to each other. . With this configuration, the sound pressure at any position within the arc tube 1 becomes a constant value, no standing waves are generated, and acoustic resonance phenomena can be avoided.

なお、本発明に係る発光管は、上記実施例に示した断面
形状及び長軸方向への変化に限定されるものではないの
は勿論である。Note that the arc tube according to the present invention is, of course, not limited to the cross-sectional shape and the change in the longitudinal direction shown in the above embodiments.

（発明の効果） 本発明は上記のように、発光管の長軸方向断面形状を不
等辺多角形にしたことにより、発光管内５− のどの位置の音圧も一定値となり、定在波が生じず、音
響的共鳴現象を回避できる。従って、本発明に係る高圧
放電灯を高周波点灯した場合、音響的共鳴現象によって
生しるアーク柱の湾曲、揺らぎ、立ち消え、発光管の破
損等が防止でき、安定した点灯を維持することができる
。(Effects of the Invention) As described above, in the present invention, by making the cross-sectional shape of the arc tube in the long axis direction into a scalene polygon, the sound pressure at any position within the arc tube becomes a constant value, and standing waves are prevented. Therefore, the acoustic resonance phenomenon can be avoided. Therefore, when the high-pressure discharge lamp according to the present invention is lit at high frequency, it is possible to prevent arc column curvature, fluctuation, extinguishing, and arc tube damage caused by acoustic resonance phenomena, and to maintain stable lighting. .

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

第１図は従来の高圧放電灯の一例を示す正面図、第２図
及び第３図はそれぞれ本発明に係る発光管の一実施例を
示し、各図において（ａｌは正面図、（ｂ）は各図ｆａ
）におけるＡ−Ａ’線断面図である。 特許出願人 松下電工株式会社 代理人　弁理士　竹元敏丸 （ほか２名） ＝６一 第１図 Ａｎ ｌ　第３ ・ｉ　、。、 第２；ンζ１ （Ｑ）　（ｆ：＋）FIG. 1 is a front view showing an example of a conventional high-pressure discharge lamp, and FIGS. 2 and 3 each show an embodiment of an arc tube according to the present invention. In each figure, (al is a front view, (b) is each figure fa
) is a sectional view taken along line AA' in FIG. Patent applicant Matsushita Electric Works Co., Ltd. Agent Patent attorney Toshimaru Takemoto (and 2 others) =61 Figure 1 An l 3.i. , 2nd;nζ1 (Q) (f:+)

Claims (2)

【特許請求の範囲】[Claims] （１）長軸方向の断面形状が不等辺多角形の発光管を具
備して成る高圧放電灯。(1) A high-pressure discharge lamp comprising an arc tube with a scalene polygon cross-section in the longitudinal direction. （２）発光管を構成する面同志がいずれも平行でない特
許請求の範囲第１項記載の高圧放電灯。(2) The high-pressure discharge lamp according to claim 1, in which the surfaces constituting the arc tube are not parallel to each other.