JP2003092080A - High-pressure discharge lamp and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp equipped with a translucent ceramic discharge vessel which keeps the coolest-part temperature at a required value and restrains color temperature change when changing lighting directions, and a lighting device using the same. SOLUTION: A translucent ceramic discharge vessel 1 with an enveloping part 1a surrounding a discharge space and small-diameter cylinder parts 1b communicating with both ends of the enveloping part 1a integrally molded, with the outer surface of the boundary part of the enveloping part 1a and the small-diameter pars 1b of a continuous concave curve face CF and with the inner face forming a discontinuous inflection point DP, a pair of electrodes 2, 2 inserted into the small-diameter cylinder parts forming a slight gap g against the inside faces of the small-diameter cylinder parts 1b, lead-in conductors 3 with the tips connected to base end parts of the electrodes 2 and with at least the middle parts sealed and adhered to the translucent discharge vessel 1, and a discharge medium are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high pressure discharge lamp provided with a translucent ceramics discharge vessel and an illuminating device using the same.

[0002]

2. Description of the Related Art In recent years, metal halide lamps equipped with a discharge container made of translucent ceramic have become popular. Compared with conventional metal halide lamps equipped with a quartz glass discharge vessel, this metal halide lamp has the characteristics of high efficiency and long life, as well as the feature that there is little change in color temperature during life and color variation between lamps. .

The translucent ceramics discharge vessel used in a high pressure discharge lamp such as a metal halide lamp having a conventional translucent ceramics discharge vessel has a cylindrical portion, a disc-shaped portion and a pipe-shaped portion which are shrink-fitted. Many of them have the structure (prior art 1). In this case, in the translucent ceramics discharge vessel, the cylindrical portion and the disk-shaped portion form the surrounding portion that surrounds the discharge space, and the pipe-shaped portion forms the small diameter cylindrical portion. The high-pressure discharge lamp provided with the translucent ceramics discharge vessel of this structure has little change in color temperature when the lighting direction is changed. This is because the change in the coldest part temperature is small. In the conventional high pressure discharge lamp described above, the coldest portion is formed near one end of the pipe-shaped portion. The temperature of this portion is determined by the balance between the conduction heat and the radiant heat from the electrodes and the heat conduction amount of the translucent ceramics discharge vessel. And if you change the lighting direction,
Although the conduction heat and the radiant heat from the electrodes are almost constant, the heat conduction amount of the translucent ceramics discharge vessel changes greatly. That is, during horizontal lighting, the arc bends upward and approaches the upper wall surface of the translucent ceramics discharge vessel, thereby heating the upper portion more. However, the thermal conductivity of ceramics such as translucent alumina used for the translucent ceramics discharge vessel is much higher than that of quartz glass. Therefore, the amount of heat conduction to the end of the small-diameter cylindrical part where the coldest part is formed is increased, and the temperature of the coldest part changes and the color temperature changes. The fitting part acts as a thermal resistance, limiting the amount of heat transfer to the small-diameter cylinder part where the coldest part is formed, to some extent to reduce the color temperature change so as not to impair practical use. This is the reason why the change in color temperature (that is, the lighting direction characteristic) when changing is small.

On the other hand, Japanese Patent Laid-Open No. 9-147803, the same as 1
As seen in Japanese Patent Publication No. 1-204086, a translucent ceramics discharge container integrally formed by casting or the like is also used. (Prior Art 2) In the prior art 2, although the heat capacity tends to be relatively small, both the inner and outer surfaces of the boundary portion between the surrounding portion and the small-diameter tubular portion are formed into gentle continuous curved surfaces. , Both the inner and outer surfaces are formed into discontinuous curved surfaces.

By the way, when the high-pressure discharge lamp is lit at a high frequency, it is necessary to avoid acoustic resonance. For that purpose, it is desirable to unify the acoustic resonance modes of the translucent ceramics discharge vessel. In order to realize this, it is necessary to make the inner surface of the surrounding portion of the translucent ceramics discharge vessel a spherical shape. However, in the prior art 2, the translucent ceramics discharge vessel whose surrounding portion is formed as close to a spherical shape as possible is disclosed in, for example, Japanese Patent Laid-Open No. 9-147.
As seen in Japanese Patent Publication No. 803, discontinuous inflection points are formed on both inner and outer surfaces of the boundary between the surrounding portion and the small-diameter cylindrical portion, and the electrode which becomes hot during lighting is located near the inflection point. Therefore, there is a problem that a large thermal stress is generated at the inflection point, and the small-diameter cylindrical portion is easily broken during manufacturing, or cracks are easily generated during lighting. On the other hand, in the prior art 2, the inner surface and the outer surface of the boundary portion between the surrounding portion and the small-diameter cylindrical portion are formed into a continuous curved surface, the mechanical strength is improved, and the above-mentioned problem is solved.

[0006]

However, there is a strong demand for a smaller change in color temperature than in the prior art 1. Further, in the case of the translucent ceramics discharge vessel having the shrink fitting structure of the conventional technique 1, the heat capacity tends to be relatively large. Therefore, when the lamp power decreases,
There is a problem that the coldest part temperature necessary to secure high efficiency cannot be secured.

Further, in the prior art 2, the inner and outer surfaces of the boundary portion between the surrounding portion and the small diameter cylindrical portion are formed into a continuous curved surface, and the problem of the lighting direction characteristic cannot be solved. That is, when both the inner and outer surfaces of the boundary portion between the surrounding portion and the small-diameter cylindrical portion are continuous curved surfaces, conduction heat and convection heat during lighting are easily conducted to the coldest portion, so that the lighting direction characteristic is increased. Therefore, in order to reduce the characteristics of the lighting direction, it is effective to increase the amount of the metal halide enclosed, because the position of the metal halide is less likely to change when the lighting direction is changed. However, this time, impurities such as H ₂ O, which are easily mixed in the metal halide, increase, so that the lamp characteristics during the life may be significantly deteriorated.

Further, a high pressure discharge lamp having improved starting performance has been developed in which a starting auxiliary conductor made of a conductive metal wire and composed of a coil connected to the opposite electrode and a conductive position is wound around a small-diameter cylindrical portion. . In this case, a capacitance is formed between the starting auxiliary conductor and the electrode surrounded by the starting auxiliary conductor. Then, a small amount of pioneering discharge is generated through this capacitance to accelerate the starting. Therefore, the capacitance is effective in setting the glow-arc transition time to an appropriate value (0.5 to 3 seconds). That is, at the time of starting, a small amount of precursory discharge is generated between the coil and the electrode inserted in the small-diameter cylindrical portion through the capacitance, thereby assisting the starting. However, there is a problem that, when a minute discharge occurs, a thermal shock is applied to the boundary between the surrounding portion of the translucent ceramics discharge vessel and the small-diameter cylindrical portion, and a crack easily occurs at the boundary.

Furthermore, it is expected that the startability will be further improved by disposing the auxiliary starting conductors in the pair of small-diameter cylindrical portions of the translucent ceramics discharge vessel. In this case, even if the number of turns of the coil of the starting auxiliary conductor is made equal, the glow-arc transition time in the pair of electrodes is actually different, and therefore the power required for glow-arc transition is short at the shorter glow discharge time. Since it is charged into the electrode in a time, the electrode is excessively heated and the evaporation of the electrode material is increased, resulting in blackening of the translucent ceramics discharge vessel.

The present invention uses a high-pressure discharge lamp provided with a translucent ceramics discharge vessel, which secures the temperature of the coldest portion to a required value and suppresses the color temperature change when the lighting direction is changed, and the same. An object is to provide a lighting device.

According to the present invention, in addition, the acoustic resonance modes of the translucent ceramics discharge vessel are unified to facilitate the avoidance of acoustic resonance, and the boundary between the surrounding portion and the small diameter cylindrical portion of the translucent ceramics discharge vessel. Another object of the present invention is to provide a high-pressure discharge lamp in which a crack due to thermal stress is unlikely to occur in its part and a lighting device using the same.

The present invention also provides a high-pressure discharge lamp and a lighting device using the same, in which cracks are less likely to occur due to thermal shock due to precursory micro-discharging caused by disposing a coil for starting assistance in a small-diameter cylindrical portion. Still another purpose is to provide.

The present invention additionally provides a high pressure discharge lamp which suppresses the blackening of the translucent ceramics discharge vessel, which is likely to occur due to the provision of a coil for starting assistance in the small-diameter cylindrical portion, and a lighting device using the same. Yet another purpose is to provide.

[0014]

A high-pressure discharge lamp according to the invention of claim 1 is integrally formed with an enclosing portion enclosing a discharge space and a small-diameter cylindrical portion communicating with both ends of the enclosing portion, and is enclosed. And a translucent ceramics discharge vessel in which an outer surface of a boundary portion between the cylindrical portion and the small-diameter cylindrical portion is a continuous curved surface, and inflection points of which the inner surface is discontinuous are formed, respectively; A pair of electrodes inserted into the small-diameter cylindrical portion and having their tips facing the surrounding portion of the translucent discharge vessel; the tips are connected to the proximal ends of the electrodes, and at least the middle section is sealed in the translucent vessel. It is characterized in that it is equipped with an introduction conductor that is attached and has its base end exposed from the translucent discharge vessel to the outside; and a discharge medium enclosed in the translucent ceramics discharge vessel.

In the present invention and the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified. As described above, the high-pressure discharge lamp of the present invention comprises the translucent ceramics discharge vessel, the pair of electrodes, the introduction conductor and the discharge medium as constituent elements. Hereinafter, each component will be described.

<Translucent Ceramics Discharge Vessel>
"Translucent ceramics discharge vessel" means a single crystal metal oxide such as sapphire and a polycrystalline metal oxide such as translucent hermetic aluminum oxide or yttrium-.
It means a discharge vessel made of aluminum-garnet (YAG), yttrium oxide (YOX), and a material having a light-transmitting property and a heat resistance, such as a polycrystalline non-oxide such as aluminum nitride (AlN). The term "translucent" means that the light generated by the discharge can be transmitted and guided to the outside, and it may be not only transparent but also light diffusive. Then, at least the surrounding portion has a light-transmitting property, and if necessary, the small-diameter cylindrical portion may have a light-shielding property.

Further, the translucent ceramics discharge vessel is provided with an enclosing portion enclosing the discharge space and a small-diameter cylindrical portion arranged in communication with the end portion of the enclosing portion. Then, the surrounding portion and the small-diameter cylindrical portion are integrated by integral molding. Therefore, there is no inhomogeneous structure of the material cross section due to shrink fitting.
The surrounding portion is allowed to have a continuous curved inner surface in order to surround the discharge space therein.
Furthermore, the main part inside the surrounding part can be made into a spherical hollow. The term “spherical” is preferably a spherical shape because the acoustic resonance frequency becomes a single mode, but may be an elliptic shape if necessary. The "main part" of the surrounding part is a large part of the remainder excluding the vicinity of the end on the side in contact with the small-diameter cylindrical part, and the part through which the light emitted by the discharge is mainly transmitted.

Next, in the small-diameter cylindrical portion, an electrode and an introducing conductor to be connected to the electrode, which will be described later, are inserted into the small-diameter cylindrical portion, a slight gap called a capillary is formed around the electrode, and the coldest portion is formed inside the small-diameter cylindrical portion. While being formed, it contributes to sealing the translucent ceramics discharge vessel. In addition, in order to reduce the heat capacity as much as possible, the inner diameter of the small-diameter tubular portion is 1 mm or less,
It is preferably 0.8 mm or less. Further, the cross section of the small diameter tubular portion is preferably substantially circular.

By the way, the structural feature of the present invention is that in the translucent ceramics discharge vessel having the above-mentioned structure, the outer surface of the boundary portion between the surrounding portion and the small diameter cylindrical portion is a continuous concave surface and the inner surface is That is, discontinuous inflection points are formed. The degree of the concave curved surface is not particularly limited. However, when the radius of curvature of the concave curved surface is r and the maximum inner diameter of the surrounding portion is R, it is more effective if the following expression is satisfied.

0.1 ≦ r / R ≦ 1.5 When r / R is less than 0.1, the mechanical strength is lowered, and the small-diameter cylindrical portion is liable to be broken during manufacture, and the life is shortened. Due to the heat cycle, cracks are likely to occur in the small diameter cylinder. Further, when r / R exceeds 1.5, it is difficult to efficiently cool the lamp voltage forming medium such as mercury as a discharge medium, so that a problem is likely to occur during manufacturing.

Furthermore, by setting the relationship between the inner diameter of the surrounding portion of the translucent ceramics discharge vessel and the total length L to satisfy the following equation, the translucent ceramics discharge vessel of the translucent ceramics discharge vessel can be maintained while maintaining desired lamp characteristics. Leakage can be suppressed.

0.1 <R / L <0.3 If R / L is less than 0.1, it becomes difficult to maintain the temperature of the coldest part at a required value, so that the luminous efficiency decreases. , The desired emission color cannot be obtained. Further, when R / L exceeds 0.3, a leak is likely to occur in the seal portion of the translucent ceramics discharge vessel.

Further, the total length L of the translucent ceramics discharge vessel is related to the supplied lamp power W, and W / L
Is set so as to satisfy the following equation, a good high pressure discharge lamp can be obtained.

0.5 <L / W <1.8 If L / W is less than 0.5, a leak is likely to occur in the sealed portion of the translucent ceramics discharge vessel. When L / W exceeds 1.8, it becomes difficult to maintain the temperature of the coldest part.

Further, in the present invention, the total length and the internal volume of the translucent ceramics discharge vessel are not particularly limited.
However, in order to obtain a compact high-pressure discharge lamp having a lamp power of about 10 to 50 W, and more preferably 10 to 30 W, the total length is generally 35 mm or less, preferably 1 mm.
It is preferably 0 to 30 mm. The internal volume is 0.1
It is 0 cc or less, preferably 0.01 to 0.08 cc.

Furthermore, the maximum temperature on the outer surface of the translucent ceramics discharge vessel during lighting is 1000 to 120.
It is preferably designed to be 0 ° C.

<Regarding a Pair of Electrodes> The pair of electrodes are inserted into the small-diameter cylindrical portion while forming a slight gap between the pair of electrodes and the inner surface of the small-diameter cylindrical portion of the translucent ceramics discharge vessel, and the tips are transparent. It faces the surrounding part of the photodischarge vessel. Further, the electrode can be formed using a conductive material such as tungsten, rhenium, doped tungsten, a tungsten-rhenium alloy, molybdenum, or cermet and using a refractory substance alone or in an appropriate combination. Further, the electrode may preferably be composed of an elongated electrode shaft portion and an electrode main portion arranged at the tip of the electrode shaft portion. In this case, the electrode main part is a part which is disposed at the tip of the electrode shaft and mainly acts as a cathode and / or an anode, and constitutes the tip part of the electrode. Also,
A coil of tungsten, rhenium, or the like can be wound around the electrode main portion as necessary in order to increase the surface area and improve heat dissipation.

Next, as described above, the tip of the electrode is positioned so as to face the inside of the surrounding portion, but "to face the inside of the surrounding portion".
Is a concept including a mode of being located in the surrounding section and a mode of being located in a small-diameter cylindrical section communicating with the surrounding section.

Further, it is desirable that the intermediate portion of the electrode has a constant thickness in order to form a gap as small as possible, that is, a capillary, with the inner surface of the small-diameter cylindrical portion of the translucent discharge vessel. Furthermore, it is permitted to wind a coil of pure tungsten, rhenium, a tungsten-rhenium alloy or a doped tungsten in the middle of the electrode. This facilitates centering of the electrode with respect to the small-diameter cylindrical portion.

Further, the base end portion of the electrode is fixed at a required relative position with respect to the translucent discharge vessel, and is fixed by welding or the like to the tip end of the introduction conductor which functions to introduce an electric current from the outside. To be supported electrically and mechanically. For the purpose of thermal buffering during welding, it is possible to dispose a member such as molybdenum or cermet at the tip of the introduction conductor described later and to interpose the member with the base end of the electrode. it can.

<Introducing Conductor> The introducing conductor is a conductor that functions to apply a voltage between the electrodes, supply a current to the electrodes, and seal the translucent ceramics discharge vessel. Of the transparent ceramics discharge vessel, and at least the middle portion is sealed to the small-diameter cylindrical portion of the transparent ceramics discharge vessel, and the proximal end is exposed to the outside of the transparent discharge vessel. Incidentally, "exposed to the outside of the translucent discharge vessel" may be projected from the translucent discharge vessel to the outside,
Although it does not have to project, it means that it is exposed to the outside so that power can be supplied from the outside.

Further, as the introduced conductor, niobium, tantalum, titanium, zirconium, hafnium, vanadium, etc. which are conductive metals having a thermal expansion coefficient similar to that of translucent ceramics can be used. When aluminum oxide such as alumina ceramics is used as the material of the translucent ceramics discharge vessel, niobium and tantalum are suitable for sealing because their average thermal expansion coefficient is almost the same as that of aluminum oxide. The difference is also small in the case of yttrium oxide and YAG. When aluminum nitride is used in the translucent ceramics discharge vessel, zirconium may be used as the lead conductor. Further, since the above-mentioned metal used for the introduction conductor has hydrogen and oxygen permeability, it can be contributed to discharge the impure gas remaining inside the translucent ceramics discharge vessel, if desired. . In addition, the introduction conductor, by supporting this,
It may be used to support the entire high pressure discharge lamp.

Further, the introduction conductor may be constituted by a rod-shaped body, a pipe-shaped body or a coil-shaped body made of a sealing metal such as niobium. In this case, niobium and the like have a strong oxidizing property, so when the high-pressure discharge lamp is lit in the atmosphere, the oxidation-resistant conductor should be further connected to the introduction conductor and the introduction conductor should not come into contact with the atmosphere. It is necessary to cover it with, for example, a seal.

<Discharge Medium> As the discharge medium, a light emitting metal halide, a lamp voltage forming medium, and a rare gas can be used, for example, in the following combinations. The luminescent metal halide is a luminescent metal halide that emits visible light. The lamp voltage forming medium includes
Mercury or halide can be mainly used. Mercury can be used in 3. In the case of, it also contributes as a light emitting metal. The halide as the lamp voltage forming medium has a relatively high vapor pressure during lighting and a relatively low emission in the visible region, such as Al, Fe, Zn, Sb and Mn.
Halides such as are preferred. The noble gas acts as a starting gas and a buffer gas. As the rare gas, xenon, argon, krypton, neon or the like can be used alone or in combination. In the present invention, "high-voltage discharge" refers to a discharge in which the pressure during lighting of the ionized medium becomes equal to or higher than atmospheric pressure, and is a concept including so-called ultra-high-voltage discharge.

1. Light emitting metal halide + mercury + rare gas: A so-called metal halide lamp.

2. Halide of light emitting metal + halide as lamp voltage forming medium + rare gas: This is a so-called mercury-less metal halide lamp configuration that does not use mercury, which has a large environmental load.

3. Mercury + noble gas: This is a so-called high-pressure mercury lamp.

4. Noble gas: When Xe is used as a rare gas, it is a so-called xenon lamp configuration.

Next, as the halide of the luminescent metal, any one kind or plural kinds of iodine, bromine, chlorine or fluorine can be used as halogen. The metal halide of the luminescent metal is used to obtain visible light emission having desired emission characteristics such as emission color, average color rendering index Ra, and emission efficiency. Accordingly, it can be arbitrarily selected from known metal halides. For example, sodium Na, lithium Li, scandium S
One or more halides selected from the group consisting of c, thallium Tl and rare earth metals can be used.

<Regarding Other Configurations> In the present invention, although not an essential configuration requirement, a part or all of the following configurations can be provided as desired.

(1) Sealing of a compound for sealing ceramics An introducing conductor having an electrode at its tip is inserted into a small diameter cylindrical portion of a transparent ceramics discharge vessel to seal the transparent ceramics discharge vessel and the introducing conductor. A ceramic sealing compound seal can be used to attach and seal the translucent ceramics discharge vessel. Then, in order to perform the sealing using the seal of the compound for ceramics sealing, it is applied between the introduction conductor and the small diameter tubular portion on the end face of the small diameter tubular portion, and is melted by heating to melt the small diameter tubular portion and the introduction conductor. It penetrates into the space and solidifies by cooling to hermetically seal the space between them. The introduction conductor is fixed at a predetermined position by this seal.

The introduction conductor inserted in the small-diameter cylindrical portion is
Complete coverage by the seal is desirable. Further, the proximal end portion of the elongated electrode having the seal fixed to the introduction conductor is slightly separated, preferably 0.2 to 3 mm.
If it is configured to cover over, the introduced conductor is less likely to be corroded by the discharge medium such as a halide.

(2) Starting auxiliary conductor When the inner diameter of the surrounding portion of the translucent ceramics discharge vessel is increased and the distance between the electrodes is increased correspondingly, the starting voltage of the high pressure discharge lamp tends to rise. So, by arranging the starting auxiliary conductor if necessary,
The starting voltage can be reduced. The starting auxiliary conductor is disposed on the outer circumference of the small-diameter cylindrical portion through which at least one electrode is inserted, and is the same as the other electrode facing the electrode surrounded by the starting auxiliary conductor through the discharge space. It can be constituted by a metal coil connected so as to have a potential.

(3) Outer tube The high-pressure discharge lamp of the present invention can be constructed so that it is lit while the translucent ceramics discharge vessel is exposed to the atmosphere. However, if necessary, the translucent ceramics discharge vessel can be hermetically housed in the outer tube. In addition,
By forming the inner surface of the outer tube as a reflecting surface having the light emitting portion of the high pressure discharge lamp as a focal point, a high pressure discharge lamp having directivity can be obtained.

(4) Reflector The high pressure discharge lamp of the present invention can be integrated with the reflector. In this case, a reflecting mirror may be formed on the inner surface of the outer tube that houses the translucent ceramics discharge vessel, or the high-pressure discharge lamp may be assembled in a separately provided reflecting mirror. Further, a reflecting mirror may be attached without using the outer tube.

(5) Regarding the relationship between the diameter of the introduced conductor and the diameter of the electrode: The diameter of the introduced conductor is φs (mm), and the diameter of the electrode is φe.
It is effective to satisfy the following formula when (mm) is set.

0.2 ≦ φe / φs ≦ 0.6 That is, the temperature of the seal of the ceramics sealing compound is reduced to prevent the seal from being corroded by a halide and to raise the temperature of a slight gap. In order to improve the light emission efficiency by increasing the thickness of the introduced conductor as much as possible to reduce its thermal resistance on the one hand, it is preferable to increase the thermal resistance of the electrode on the other hand. The diameter ratio φe / φs
Is less than 0.2, the electrode becomes too thin. Also, 0.6
When it exceeds, it becomes difficult to maintain the temperature of the seal and the temperature of the slight gap at a required value.

(6) Relationship between inner volume of translucent ceramics discharge vessel and linear transmittance The inner volume of the translucent ceramics discharge vessel is set to 0.1 cc or less, preferably 0.07 cc or less, and the hollow portion The average linear transmittance can be 10% or more, preferably 30% or more. However, the linear transmittance is 550n
It shall be measured at m. Further, the “average linear transmittance” means a value obtained by arithmetically averaging the linear transmittance data measured at five different positions with respect to the target portion. Furthermore, the internal volume of the translucent ceramics discharge vessel is determined by placing the vessel in water and filling the inside with water,
Block the open ends of both small diameter cylinders and take them out of the water.
Lighten the water inside and measure.

In the case of a translucent ceramics discharge vessel having a small internal volume as described above, if the average linear transmittance of the surrounding portion is 10% or more, the optical efficiency (equipment efficiency) with an optical system to be combined, for example, a reflecting mirror. ) Can be increased,
The translucent ceramics discharge vessel is less likely to crack.

(7) Lamp Power The present invention is suitable for small metal halide lamps having a lamp power of about 10 to 50 W. However, more preferably 10
~ 30W. In addition, the tube wall load is 15 to 45 W / c
A range of m ² is preferred.

<Operation of the Present Invention> In the present invention, the inner surface of the boundary portion between the surrounding portion of the translucent ceramics discharge vessel and the small diameter cylindrical portion is discontinuously curved due to the provision of the above-described configuration. Since the points are formed, the heat capacity of the boundary portion is increased together with the increase in the thickness of the portion, and as a result, the thermal isolation between the discharge space and the coldest portion is performed.
Therefore, the movement of the halide is reduced, so that the temperature of the coldest portion formed in the small-diameter cylindrical portion is stabilized. This allows
The lighting direction characteristics of the high-pressure discharge lamp are improved. As a result, the maximum change in color temperature with respect to the lighting direction can be kept within ± 150K.

According to a second aspect of the present invention, in the high pressure discharge lamp according to the first aspect, the translucent ceramics discharge vessel is characterized in that the inner surface of the surrounding portion is substantially spherical.

In the present invention, the boundary portion between the surrounding portion of the translucent ceramics discharge vessel and the small diameter cylindrical portion forms a discontinuous inflection point, so that the surrounding portion is formed into a substantially spherical shape. It is possible that the acoustic resonance frequencies are unified. The term "substantially true sphere" means that the shape is substantially true sphere, and some degree of manufacturing deformation is allowed. Generally, when a high-pressure discharge lamp is lit at a high frequency, its operating frequency is set to a frequency band existing between the second harmonic and the third harmonic of the fundamental frequency of the acoustic resonance frequency. The frequency band is, for example, 9 to 10 kHz, and the bandwidth is expanded by about 2 kHz, which facilitates the design of the high frequency lighting circuit.

A high-pressure discharge lamp according to a third aspect of the present invention is the high-pressure discharge lamp according to the first or second aspect, wherein the high-pressure discharge lamp is arranged around the small-diameter cylindrical portion of the translucent ceramics discharge vessel and inserted into the small-diameter cylindrical portion. It is characterized in that it includes a starting auxiliary conductor which is surrounded by the starting electrode and which has the same electric potential as the counter electrode.

In the present invention, the "opposing electrode" means an electrode facing the electrode surrounded by the starting auxiliary conductor via the small diameter cylindrical portion via the discharge space. Also,
The starting aid conductor may be disposed on both or one of the pair of electrodes. In order to make the starting auxiliary conductor have the same potential as the counter electrode, for example, the starting auxiliary conductor may be connected to the counter electrode via the conductor.

The starting auxiliary conductor is wound around the outer circumference of the one small-diameter cylindrical portion through which the first electrode is inserted, and is connected so that one end thereof has the same potential as the second electrode. And a second metal that is wound around the outer periphery of the other small-diameter tubular portion through which the second electrode is inserted and that is connected so that one end has the same potential as the first electrode. It can be configured with a coil.

Further, it is effective to dispose the starting auxiliary conductor so that its end portion is close to the boundary portion between the surrounding portion of the translucent ceramics discharge vessel and the small diameter cylindrical portion. Further, the starting auxiliary conductor can be formed by a metal coil, a conductive coating, or the like.

A preferred structure of the starting auxiliary conductor is shown below.
In implementation, one or more of the following items can be combined.

1 The number of turns of the metal coil is 4 turns or more.

2 The winding pitch of the metal coil is 100 to
Make it 500%.

3 The length of the metal coil is L _SA 1,
When the length of the small diameter cylinder is L _SA 2, L _SA 1 / L
_SA 2 is set to 0.3 to 1.0. (See FIG. 3) Thus, in the present invention, the inner surface of the boundary portion between the surrounding portion of the translucent ceramics discharge vessel and the small diameter cylindrical portion is a discontinuous inflection point, and the outer surface is continuous. As a result of being respectively formed on the concave curved surface, the mechanical strength of the small-diameter cylindrical portion is improved as described above, so that the small-diameter cylindrical portion due to the thermal stress due to the precursory discharge between the starting auxiliary conductor and the electrode arranged in the small-diameter cylindrical portion. Occurrence of defects such as cracks at the base of the portion, that is, near the boundary is reduced. Of course, it goes without saying that the provision of the starting auxiliary conductor improves the starting characteristics of the high-pressure discharge lamp.

A high pressure discharge lamp according to a fourth aspect of the present invention is the high pressure discharge lamp according to any one of the first to third aspects, which comprises a metal coil and is wound around a pair of small-diameter cylindrical portions of the translucent ceramics discharge vessel. It is characterized in that it includes a pair of starting auxiliary conductors that surround the electrodes that are inserted into the inside of the small-diameter cylindrical portion and that have the same potential as the opposing electrodes and that are asymmetrical to each other.

In the present invention, the fact that the pair of starting auxiliary conductors are "asymmetrical structure" means that the structures are asymmetrical so that the starting auxiliary functions are not equal. The unequal starting assist functions can be realized, for example, by the fact that the starting assist conductor and the electrode surrounded by the small diameter tubular portion have different capacitances. This capacitance changes one or more of the distance between the starting auxiliary conductor and the electrode, the relative permittivity of the small-diameter tubular portion, and the effective area between the starting auxiliary conductor and the electrode facing the auxiliary auxiliary conductor. Depending on the situation,
It is easiest to change the latter. In addition, the effective area between the starting auxiliary conductor and the electrode facing it is
This can be easily changed by changing the effective area of the starting auxiliary conductor. For example, in the case of a starting auxiliary conductor made of a metal coil, the capacitance can be changed by changing the number of turns of the coil, the diameter of the coil or the coil pitch.

By the way, a suitable glow-arc transition time at the pair of electrodes at the time of starting is, for example, 0.5.
It is about 3 seconds, but if this time is shorter than the preferable time, the electric power required for glow-arc transition is supplied in a short time, so that the electrode is excessively heated and the constituent materials such as tungsten are evaporated. Increase and cause blackening of the translucent ceramics discharge vessel. Such a phenomenon is caused by a small amount of discharge medium held in the small-diameter cylindrical portion having a higher temperature, and the glow power injected into the electrode inserted in the small-diameter cylindrical portion is generated in the small-diameter cylindrical portion during precursory discharge. In addition, the discharge medium is not consumed as energy for vaporization.

On the other hand, according to the present invention, the electrostatic capacitance of the starting auxiliary conductor disposed in the small-diameter cylindrical portion having a high temperature, such as the small-diameter cylindrical portion which is turned on during lighting, is increased. It may be asymmetrical with respect to the opposite starting auxiliary conductor.

As a result, the electrostatic capacitance between the teaching auxiliary conductor asymmetrical as described above and the electrode surrounded by it becomes large, and accordingly, the precursory fine discharge current at the time of starting is relatively large. Become. As a result, the energy consumed for evaporation of the discharge medium increases, the heating of the electrode is suppressed accordingly, and the blackening is reduced.

A lighting device according to a fifth aspect of the present invention includes a lighting device main body; a high-pressure discharge lamp according to any one of claims 1 to 4 supported by the lighting device main body; and a lighting circuit for lighting the high-pressure discharge lamp. It is characterized by having;

In the present invention, the "illumination device" is a broad concept including all devices that use the light emission of the high pressure discharge lamp for some purpose. For example, it can be applied to a light bulb type high-pressure discharge lamp, a lighting fixture, a headlight for a moving object, a light source device for optical fiber, an image projection device, a photochemical device, a fingerprint discrimination device, and the like. The "illuminator main body" refers to the remaining portion of the above-mentioned illumination device except the high-pressure discharge lamp and the lighting circuit.

A "bulb-shaped high-pressure discharge lamp" is a high-pressure discharge lamp integrated with its high-frequency lighting circuit, and is further equipped with a base for power reception, and is attached to a lamp socket suitable for the base. Means an illuminating device configured so that the incandescent light bulb can be used as if it were lit. In the case of forming a light bulb type high pressure discharge lamp, a reflector for converging the light emitted from the high pressure discharge lamp may be provided so that desired light distribution characteristics can be obtained.
Furthermore, in order to reduce the high brightness of the high-pressure discharge lamp,
A light diffusing glove or cover can be provided. Furthermore, the mouthpiece having a desired specification can be used. Therefore, for the purpose of replacing the conventional light source lamp, the same cap as that of the conventional light source lamp may be adopted.

The lighting circuit may be either AC or DC lighting. Further, in the case of AC lighting, either high frequency or low frequency may be used. However, the high-pressure discharge lamp used in the present invention, in which the translucent ceramics discharge vessel is integrally molded with the surrounding portion and the small-diameter cylindrical portion, and is suitable for those having a high sphericity of the surrounding portion, Since it is easy to avoid the influence of the acoustic resonance phenomenon, it is suitable for high frequency lighting in a frequency range of about 5 to 200 kHz. For example, an inverter can be used as the high frequency generating means.
The inverter may be of various circuit types such as a half-bridge type inverter and a full-bridge type inverter. As the current limiting impedance, one kind or a combination of a plurality of kinds of inductance, capacitance and resistance can be used, but the inductance is suitable for practical use. An inductor, a leakage transformer, or the like can be used as the inductance. Then, by forming a load circuit including a resonance circuit of a current limiting inductance and a capacitor to form a lighting circuit having continuous load characteristics from a secondary open circuit voltage to a secondary short circuit current, high frequency lighting In this case, the lighting circuit can be made small and lightweight, which is particularly preferable.

On the other hand, in the case of low frequency lighting, it is preferable that the lighting circuit uses a circuit configuration mainly composed of a step-up chopper or a step-down chopper and a full-bridge type inverter that operates by using the DC output voltage thereof as a power source. is there. In addition,
In this configuration, the inductor of the chopper acts as a current limiting inductance, so that an apparent current limiting impedance is unnecessary.

Further, in the case of direct current lighting, the lighting circuit has a circuit structure in which a step-down discharge lamp is connected to the output terminal of the step-up chopper or step-down chopper, and the size and weight of the lighting circuit can be further reduced. Therefore, it is preferable.

The lighting circuit may be arranged in the main body of the lighting device, or may be arranged in a position separated from the main body of the lighting device, for example, in the back of the ceiling.

[0074]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment of a high-pressure discharge lamp of the present invention. FIG. 1 is a longitudinal sectional view, and FIG. 2 is a schematic sectional view of a translucent ceramics discharge vessel. It is a figure. In each figure, 1 is a translucent ceramics discharge vessel, 2 is an electrode, 3 is an introducing conductor, and 4 is a seal. A discharge medium is enclosed inside the translucent ceramics discharge vessel 1. Hereinafter, each component will be described in detail.

<Translucent Ceramics Discharge Vessel 1> The translucent ceramics discharge vessel 1 is composed of an enclosing portion 1a and a small-diameter cylindrical portion 1b, and is wholly formed by integral molding. The surrounding portion 1a has a cavity 1a1 surrounding the discharge space therein. The small diameter cylindrical portion 1b has a through hole 1b1 inside thereof. The outer surface of the boundary between the surrounding portion 1a and the small-diameter cylindrical portion 1b is a continuous concave surface DF, and the inner surface is a discontinuous inflection point DP. The inner surface of the surrounding portion 1a has a spherical shape, and the outer surface has a spindle shape. Then, the small-diameter cylindrical portion 1b has a shape like a winding shaft rod of a spindle.

<Regarding the Pair of Electrodes 2 and 2> The pair of electrodes 2 and 2 respectively include the shaft portion 2a, the first coil portion 2b and the second coil portion 2c, and have an elongated rod shape as a whole. The first coil portion 2b is wound around the tip of the shaft portion 2a. The second coil portion 2c is wound near the base end portion of the shaft portion 2a. Then, the electrode 2 has a cavity 1 whose tip projects into the surrounding portion 1a and surrounds the discharge space.
A small gap g is formed between the through hole 1b1 and the electrode 2 by being inserted into the through hole 1b1 of the small-diameter cylindrical portion 1b facing the inside of a1.

<Regarding Introducing Conductor 3> The introducing conductor 3 is made of niobium and has a rod shape. The tip end is welded to the base end portion of the shaft portion 2a of the electrode 2, and at least the middle portion is interposed by a seal 4 described later. It is sealed to the small-diameter cylindrical portion 1 b of the translucent ceramics discharge vessel 1 and the base end projects to the outside of the translucent ceramics discharge vessel 1.

<About Seal 4> The seal 4 is interposed between the small-diameter cylindrical portion 1b of the translucent ceramics discharge vessel 1 and the introducing conductor 3 by melting and solidifying the ceramics sealing compound, and the translucent light is transmitted. The airtight ceramics discharge vessel 1 is hermetically sealed, and the introduction conductor 3 is sealed.
Moreover, the transparent ceramics discharge vessel 1 is covered so as not to be exposed inside. In addition, this sealing allows the electrode 2
Is fixed in place.

In order to form the seal 4, a ceramics sealing compound is applied to the end face of the small-diameter cylindrical portion 1b around the portion of the lead-in conductor 3 projecting outward from the through hole 1b1 and heated and melted. Introduction conductor 3 and through hole 1
The entire introduction conductor 3 inserted into the small-diameter cylindrical portion 1b is covered by being inserted into the gap formed between the inner surfaces of b1, and the base end portion of the electrode 2 is further covered and solidified by cooling.

<Discharge Medium> The discharge medium is composed of a rare gas such as a starting gas containing neon and argon, a buffer gas, a metal halide of a luminescent metal, and mercury supplying the buffer gas. It is enclosed inside.

[Example 1] Translucent ceramics discharge vessel 1: made of translucent alumina ceramics, having a total length of 23 mm, a maximum outer diameter of 6 mm, a maximum inner diameter R = 5 mm, an outer diameter of a small-diameter cylindrical portion of 1.7 mm, and an inner diameter of 0. 0.7 mm, surrounding portion 1a and small-diameter cylindrical portion 1
The radius of curvature r of the concave curved surface CF on the outer surface of the boundary with b is r = 4 mm Electrode 2: made of doped tungsten, the shaft portion 2a has an upper electrode having a diameter of 0.25 mm, and the lower electrode has a diameter of 0.2 mm.
mm, the length is 5.8 mm, and the diameter of the first coil portion 2b is 0.
Closed winding 4 turns of 135mm doped tungsten wire,
The second coil portion 2c is a tightly wound four-turn introduction conductor of doped tungsten wire of 0.25 mm 4: Niobium, diameter 0.64 mm Slight gap g: 0.225 mm Discharge medium: Ne3% as starting gas and buffer gas
+ Ar is about 27 kPa, and a proper amount of mercury and iodides of Na, Tl, and Dy as light emitting metals (all of the halides of the light emitting metal do not evaporate during lighting, and the surplus stays in a slight gap g). The lamp power: 20W Total luminous flux: 1800lm, Luminous efficiency: 90lm / W Color temperature: 3500K Rated life: 8000h

[Example 2] Translucent ceramics discharge vessel 1: made of translucent alumina ceramics, having a total length of 31.6 mm, a maximum outer diameter of the surrounding portion of mm, a maximum inner diameter of 5.0 mm, and an outer diameter of a small diameter cylindrical portion of 1.7 mm, 3. Inner diameter 0.7 mm, radius of curvature of concave curved surface of outer surface Bo of boundary portion between surrounding portion 1a and small diameter tubular portion 1b 4.
0 mm electrode 2: made of doped tungsten, the shaft portion 2a is the upper electrode and has a diameter of 0.2 mm and a length of 2.5 mm, and the first coil portion 2b has a tight winding 4 turns of a diameter of 0.16 mm. , The second coil portion 2c is 0.13 mm
70 turns of densely wound doped tungsten wire, electrode distance 3.5 mm Introducer 3: niobium, diameter 0.64 mm Discharge medium: Ne3% as starting gas and buffer gas
+ Ar is about 13 kPa, mercury is about 2 mg, and iodides of Na, Tl, and Dy are 2.0 mg as light emitting metals. Lamp power: 21 W Total luminous flux: 1800 lm, luminous efficiency: 90 lm / W Color temperature: 3000 K Rated life: 8000 h or less, Another embodiment of the present invention will be described with reference to FIGS. 3 and 4. In the figure, the same parts as those in FIGS. 1 and 2 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 3 is a partially transparent front view showing a second embodiment of the high pressure discharge lamp of the present invention. In this embodiment,
It is different in that it has a double tube structure including starting auxiliary conductors SAC1 and SAC2. That is, the high pressure discharge lamp includes the arc tube IB, the first and second connection conductors CC1 and CC2,
Bridge conductor BC, first and second starting auxiliary conductor SA
C1, SAC2, outer tube OB, getter GT, external connection conductors OCT1, OCT2, and base B.

The arc tube IB has the same structure as the high pressure discharge lamp shown in FIG. In addition, since the metal halide and the mercury are filled in excess of the amount that evaporates, a part of the metal halide and the mercury stay in the slight gap g in the liquid state during stable lighting. The interface of the discharge medium in the liquid phase forms the coldest part.

First and second connection conductors CC1, CC2
Are made of molybdenum wires, and extend substantially parallel to each other in the axial direction of the outer tube OB with the arc tube IB sandwiched therebetween. The tip of the first connection conductor CC1 has an upper end
While being connected to the power feeding conductor 3, the intermediate portion extends substantially parallel to the axial direction of the translucent ceramics discharge vessel 1 and at a distance. The second connection conductor CC2 is
It is connected to the feeding conductor 3 of the lower electrode 2 via the bridge conductor BC.

The starting auxiliary conductors SAC1 and SAC2 are each made of a metal coil formed of molybdenum wire having a diameter of 0.3 mm. The number of turns depends on the starting auxiliary conductor SAC1.
Has 8 turns and the starting auxiliary conductor SAC2 has 4 turns.
Each of them is wound near the outer circumference of the small-diameter cylindrical portion 1b on the side of the surrounding portion 1a, that is, on the boundary side between the surrounding portion 1a and the small-diameter cylindrical portion 1b. That is, one starting auxiliary conductor SAC1 is wound around the upper small-diameter cylindrical portion 1b and is connected to the second connecting conductor CC2 at the back of the getter GT in the figure, so that the other auxiliary auxiliary conductor SAC1 on the lower side is provided. It has the same potential as the electrode 2. The other auxiliary starting conductor SAC2 is wound around the lower small-diameter tubular portion 1b, and the first connecting conductor C
By being connected to C1, it has the same potential as the electrode 2 on the opposite side in the upper part of the figure.

The outer tube OB comprises a T-shaped valve made of hard glass, a pinch seal portion ps is formed at the base end, and an exhaust tip-off portion t is formed at the tip end, and the inside is exhausted to 1.3 × 10 3. It is in a low vacuum state of about ^-2 Pa.
The pinch seal portion ps pinches when the open end of the T-shaped valve is heated and is in a softened state, and seals molybdenum by welding the first and second connection conductors CC1 and CC2 and the external connection conductors OCT1 and OCT2. The metal foil MF is formed by embedding it in an airtight manner inside. The exhaust tip-off portion t is a mark obtained by sealing the outer pipe OB and then exhausting the inside of the outer pipe OB to completely seal the exhaust pipe (not shown).

The getter GT is made of ZrAl alloy and is supported by welding on the upper end of the second connecting conductor CC1.

The external connection conductors OCT1 and OCT2 are formed by integrally extending the connection conductors CC1 and CC2 and airtightly penetrating the pinch seal portion ps of the outer tube OB to the outside.

The base B comprises an E11 type screw base conductor b1 and a ceramic base b2. The E11 type screw cap conductor b1 connects the pair of external connection conductors OCT1 and OCT2 as required. Although the ceramics base b2 is shown as seen through the inside, it is actually formed by ceramics molding, supports the E11 type screw cap conductor b1, and receives the pinch seal portion ps of the outer tube OB to receive the inorganic substance. It is fixed by an adhesive (not shown).

Since the high pressure discharge lamp of this embodiment has the same outer structure as the halogen bulb,
It is suitable as a light source that can be substituted for a lighting device such as a downlight or a spotlight for a halogen bulb.

FIG. 4 and FIG. 5 show a light bulb type high pressure discharge lamp device as a third embodiment of the high pressure discharge lamp and a first embodiment of the lighting device of the present invention, and FIG. FIG. 5 shows a high frequency lighting circuit mainly composed of a half bridge type high frequency inverter. High pressure discharge lamp 12
This embodiment is different from the embodiment shown in FIG. 3 in that the base B is not provided. In addition, in the present embodiment as a lighting device, the high-pressure discharge lamp 12, the pedestal 13, the reflecting mirror 1
4. It is characterized as a bulb-type high-pressure discharge lamp including a high-frequency lighting circuit 15, a base body 16 and a base 17.
Hereinafter, each component of the bulb-type high pressure discharge lamp will be described.

[High-Pressure Discharge Lamp 12] The high-pressure discharge lamp 12 is similar to the second embodiment shown in FIG. 3, but has no base and the external connection terminals OCT1 and OCT2 are the pinch seal portions of the outer tube OB. It protrudes upward from ps in the figure and is directly connected to the high frequency lighting circuit 15.

[Pedestal 13] The pedestal 13 is formed by molding a heat-resistant synthetic resin, and has a mounting hole 13a,
In the figure, a mounting portion 13b is provided on the upper outer peripheral edge, and a hollow cup-shaped skirt portion 13c is provided on the lower outer peripheral edge. The mounting hole 13a is for mounting the high-pressure discharge lamp 12 and the reflecting mirror 14, and the pinch seal portion ps of the high-pressure discharge lamp 12 inserted therein and the reflecting mirror 14 described later.
The edge portions 14a are fixed concentrically with an inorganic adhesive 19. The mounting portion 13b is fixed to the opening end of the base body 16 described later. The skirt portion 13c surrounds and protects the periphery of the reflecting mirror 14 and adjusts the appearance.

[Reflecting Mirror 14] The reflecting mirror 14 is arranged around the high pressure discharge lamp 12, and at least the light emitting portion, that is, the surrounding portion 1 of the high pressure discharge lamp 12.
It surrounds a. The reflecting mirror 14 is fixed to the pedestal 13. In the present embodiment, as described above, it is fixed together with the high pressure discharge lamp 12. Further, the reflecting mirror 14 is formed into a recumbent bowl shape by glass molding, and at the same time, a cylindrical edge portion 14a at the top is integrally formed, and a reflecting surface 14b made of an aluminum vapor deposition film is formed on the inner surface. . The edge portion 14a is inserted into the mounting hole 13a of the pedestal 13 and fixed to the pedestal 13 with the inorganic adhesive BC. Further, a front glass 14c is arranged in the opening of the reflecting mirror 13. The front surface 14b is
It is manufactured by molding transparent glass, and is hermetically sealed to the reflecting mirror 14 with a low melting point frit glass 18. Furthermore, nitrogen is sealed as an inert gas in the internal space formed by the reflecting mirror 14 and the front glass 14b.

[High Frequency Lighting Circuit 15] The high frequency lighting circuit 15 is mounted mainly on the upper side of the wiring board 15a in FIG. 10, and receives the external connection terminals OCT1 and OCT2 of the high pressure discharge lamp 12 from the lower surface of the wiring board 15a. , And is connected to the wiring board 15a as required.

[Base 16] The base 16 has a cup-like shape, and a base 17 to be described later is attached to the base of the base 16.
Further, a peripheral step portion 16a is formed at the opening edge. Further, the lighting circuit means 15 is housed inside the base 16. Further, the peripheral step portion 13c of the pedestal 13 is fitted into the peripheral step portion 16a at the opening edge and fixed by an adhesive. It should be noted that pores for venting air and radiating heat are formed in appropriate places of the base body 16 or a fitting portion with the pedestal.

[About the base 17] The base 17 is E26.
It is composed of a die having a shape and is attached to the base of the base 16.

Next, the circuit configuration of the high frequency lighting circuit 15 will be described with reference to FIG.

In FIG. 11, the high frequency lighting circuit 15 is
AC power supply AS, overcurrent fuse f, noise filter N
F, a rectified DC power supply RD, a high frequency inverter HFI, and a load circuit LC. Hereinafter, each component will be described.

The AC power supply AS is a commercial 100V power supply.

The overcurrent fuse f is a pattern fuse integrally formed on the wiring board and protects the circuit from being blown out and burned out when an overcurrent flows.

The noise filter NF is composed of an inductor L1 and a capacitor C1 and removes the high frequency generated by the operation of the high frequency inverter so as not to flow out to the power supply side.

The rectified DC power supply RD is composed of a bridge type rectification circuit BR and a smoothing capacitor C2, and the AC input terminal of the bridge type rectified color BR is connected to the AC power supply A via a noise filter NF and an overcurrent fuse f. , The DC output end is connected to both ends of the smoothing capacitor C2,
Supply smoothed DC.

The high frequency inverter HFI is composed of a half bridge type inverter, and is provided with first and second switching means Q1 and Q2, a gate drive circuit GD, a starting circuit ST and a gate protection circuit GP. The first switching means Q1 is an N-channel type M
It consists of OSFET, and its drain is smoothing capacitor C.
It is connected to the positive side of 2. The second switching means Q2 comprises a P-channel MOSFET, the source of which is connected to the source of the first switching means Q1,
The drain is connected to the negative side of the smoothing capacitor C2. Therefore, the first and second switching means Q1 and Q2 are connected in series in the forward direction, and both ends thereof are connected between the output terminals of the rectified DC power supply RD.

The gate drive circuit GD is a feedback circuit FB.
C, series resonance circuit SOC and gate voltage output circuit GO
Consists of. The feedback means FBC comprises an auxiliary winding magnetically coupled to a current limiting inductor L2 described later. The series resonance circuit SOC comprises a series circuit of an inductor L3 and a capacitor C3, and both ends thereof are connected to the feedback means FBC. The gate voltage output means GO is a series resonance circuit SOC.
The resonance voltage appearing across the capacitor C3 is taken out via the capacitor C4. And
One end of the capacitor C4 is connected to the connection point between the capacitor C3 and the inductor L3, and the other end of the capacitor C4 is the first
And the gates of the second switching means Q1 and Q2. Further, the other end of the capacitor C3 is connected to the sources of the first and second switching means Q1 and Q2. As a result, the resonance voltage appearing across the capacitor C3 passes through the gate voltage output circuit GO and the gate voltage of the first and second switching means Q1, Q2.
Applied between sources.

The starting circuit ST includes resistors R1, R2, R3.
Consists of. One end of the resistor R2 has a smoothing capacitor C.
2 is connected to the positive side and the other end is connected to the gate of the first switching means Q1, and one end of the resistor R2 and the output end on the gate side of the gate voltage output circuit GO of the gate drive circuit GD, that is, a capacitor. It is connected to the other end of C4. The other end of the resistor R2 has a series resonance circuit S
It is connected to the connection point of the inductor L3 of the OC and the feedback circuit FBC. One end of the resistor R3 is connected to the connection point of the first and second switching means Q1 and Q2, that is, the respective sources and the source side of the gate voltage output circuit GO, and the other end is connected to the negative side of the smoothing capacitor C2. is doing.

The gate protection circuit GP is composed of a pair of Zener diodes connected in anti-series, and has a gate voltage output circuit G
It is connected to O in parallel.

The load circuit LC is composed of a series circuit of the high-pressure discharge lamp 12, the current limiting inductor L2 and the DC cut capacitor C5, and a resonance capacitor C6 connected in parallel with the high-pressure discharge lamp 12, one end of which has the first and second ends. The other end is connected to the connection point of the switching means Q1 and Q2 and the drain of the second switching means Q2. The current limiting inductor L2 and the resonance capacitor C6 form a series resonance circuit. Since the DC cut capacitor C5 has a large capacitance, it does not significantly affect series resonance.

The capacitor C7 connected between the drain and source of Q2 reduces the load of the second switching means Q2 during switching.

Next, the circuit operation will be described.

When the AC power supply AS is turned on, the DC voltage smoothed by the rectified DC power supply RD is smoothed by the smoothing capacitor C.
Appears at both ends of 2. Then, a DC voltage is applied between the drains of the first and second switching means Q1 and Q2 connected in series. However, both switching means Q
Since the gate voltage is not applied to 1 and Q2, they are off.

Since the DC voltage is also applied to the starting circuit ST at the same time, a voltage mainly according to the proportion of the resistance values of the resistors R1, R2 and R3 appears across the resistor R2. The terminal voltage of the resistor R2 is the first and the second.
Is applied as a positive voltage between the gate and source of the switching means Q1 and Q2.

As a result, the first switching means Q1
Is set to exceed the threshold voltage, so it turns on. On the other hand, since the voltage applied between the gate and the source of the second switching means Q2 has the opposite polarity to the required gate voltage, it remains in the off state.

When the first switching means Q1 is turned on, the rectified DC power supply RD is turned on to the first switching means Q.
A current flows through the load circuit LC via 1. As a result, the series resonance circuit of the current limiting inductor L2 and the resonance capacitor C6 resonates, and a high resonance voltage appears between the terminals of the resonance capacitor C6 and is applied to the high pressure discharge lamp HPL.

On the other hand, since a current flows through the current limiting inductor L2, a voltage is induced in the feedback circuit FBC which is magnetically coupled. As a result, the series resonance circuit SOC resonates in series, and a boosted negative voltage is generated in the capacitor C3, so that the gate protection circuit GP clips the voltage to a constant voltage, and the first and second gate voltage output circuits GO. Is applied between the gate and source of the switching means Q1 and Q2.

As a result, the second switching means Q2
Turns on because it exceeds the threshold voltage.

On the other hand, the first switching means Q1 which has been on until now is turned off because the gate voltage has the opposite polarity.

When the second switching means Q2 is turned on, the electromagnetic energy accumulated in the current limiting inductor L2 of the load circuit LC and the electric charge of the capacitor C6 are released, and the current limiting inductor L2 causes the second switching means Q2 to flow. A current flows in the reverse direction through the load circuit LC, and a high voltage due to resonance in which the polarity is inverted appears at both ends of the capacitor C6 and is applied to the high-pressure discharge lamp HPL. After that, the operation described above is repeated. High frequency inverter H
The operating frequency of the FI is 45 kHz, and the high-pressure discharge lamp 12 starts well without causing an acoustic resonance phenomenon,
It lights up.

Next, the lamp specifications of the above embodiment will be described. Outer diameter: 50 mm, total length: 110 mm Base: E26 Rated voltage: 100 V Power consumption: 23 W Maximum luminous intensity: 4200 cd Beam divergence: 28 ° Beam luminous flux: 780 lm Rated life: 8000 h FIG. 6 shows the second illuminating device of the present invention. It is a partial center sectional front view showing a spotlight as an embodiment. The spotlight of the present embodiment includes a spotlight body 11, a high pressure discharge lamp 12, and a high frequency lighting circuit. Note that the high-frequency lighting circuit is separately installed and not shown.

The spotlight main body 11 mainly comprises a ceiling mounting portion 11a, an arm 11b, a main body case 11c, a lamp socket 11d, a reflecting mirror 11e, a light shielding tube 11f and a front glass 11g. The ceiling mount 11a is
The spotlight is attached to the ceiling to suspend the spotlight, and the spotlight is connected to a separately provided lighting circuit means (not shown), for example, under the ceiling, to receive power.
The base end of the arm 11b is fixed to the ceiling mounting portion 11a. The main body case 11c has a container shape with an open front surface, and is pivotally attached to the tip of the arm 11b in a vertical plane so as to be lifted and lowered. It should be noted that the two-dot chain line in the figure illustrates the range in which the elevation of the arm 11b can be adjusted with respect to the main body case 11c. The lamp socket 11d is E1
It is suitable for type 1 caps and is arranged in the main body case 11c. The reflector 11e is a lamp socket 11d.
Is located in front of the main body case 11c.
The light-shielding cylinder 11f is arranged at the center of the opening end of the reflecting mirror 11e. The front glass 11g is arranged at the open end of the main body case 11c.

The high pressure discharge lamp 12 has the same specifications as shown in FIG. Then, the high pressure discharge lamp 12 is mounted with the base B on the lamp socket 11d,
It is attached to the spotlight body 11. Also,
With the high-pressure discharge lamp 12 attached, the light-shielding tube 11f shields light from the tip of the outer tube OB to prevent glare.

FIG. 7 is a front view showing a spotlight as a fourth embodiment of the high-pressure discharge lamp and a third embodiment of the lighting device of the present invention. In the figure, 21 is a main body of a lighting fixture, and 22 is a high pressure discharge lamp.

The luminaire main body 21 includes a base 21a and a support 2
1b and the lighting body 21c.

The base 21a is constructed so as to be directly attached to the ceiling or to be hung on the ceiling via a lighting duct, and has a high-frequency lighting circuit (not shown) housed therein. The column 21b hangs down from the base 21a, and the lamp 21
Supports c. Inside the high frequency lighting circuit to the lamp body 21
It houses an insulating coating wire (not shown) connected to c. The lamp body 21c houses a lamp socket (not shown) inside.

The high pressure discharge lamp 22 comprises a high pressure discharge lamp body 22a, a glass bulb 22b with a reflecting mirror and a base 22.
It has c. The high pressure discharge lamp body 22a is similar to that shown in FIG. Glass bulb with reflector 22b
Is formed by forming an aluminum vapor deposition reflection surface 22b1 on the inner surface of the R-shaped glass bulb except the front surface. The base 22c is composed of a base conductor and a ceramic base 22c2. The base conductor is an E26 type, which is arranged inside the lamp body 21c and mounted on the high-pressure discharge lamp body 22a and the reflector-equipped glass bulb 2 socket. The ceramic base 22c2 receives the base of the integrated body 2b in a concentric relationship with the base conductor and is fixed by an inorganic adhesive.

When the base 22c of the high pressure discharge lamp 22 is attached to the lamp socket of the lamp body 21c, the high pressure discharge lamp 22 is turned on with high brightness, and the aluminum vapor deposition reflection surface 22b1 of the glass bulb 22b with a reflecting mirror is used. Since the light is condensed, a desired sharp light distribution characteristic can be obtained and the object to be illuminated can be illuminated well. Therefore, the high-pressure discharge lamp 22 of the present embodiment is suitable for replacing a mercury lamp with a reflecting mirror in a spotlight using a conventional mercury lamp with a reflecting mirror.

[0127]

According to each of the first to fourth aspects of the present invention, the enclosure portion surrounding the discharge space and the small-diameter cylindrical portion communicating with both ends of the enclosure portion are integrally formed, and the enclosure portion and the small diameter are provided. A translucent ceramics discharge vessel in which the outer surface of the boundary portion with the tubular portion is a continuous concave curved surface and the inward surface has discontinuous inflection points, respectively, and a small diameter tubular portion of the translucent ceramics discharge vessel. A pair of electrodes inserted into the small-diameter cylindrical portion while forming a slight gap between the inner surface of the electrode and the tip, and the tip was connected to the base end of the electrode and at least the middle portion was sealed to the translucent discharge vessel. Since the introduction conductor and the discharge medium are provided, the heat capacity of the boundary portion is increased, the heat isolation between the discharge space and the coldest portion is performed, and the movement of the halide is reduced. The temperature of the coldest part formed in the tube is stable, It is possible to provide a high pressure discharge lamp in which the direction characteristic is improved.

According to the second aspect of the present invention, in addition, in the translucent ceramics discharge vessel, since the inner surface of the surrounding portion is substantially spherical, the acoustic resonance frequency is unified and the acoustic resonance frequency is reduced. Since the frequency band in which the phenomenon is avoided is expanded, it is possible to provide a high pressure discharge lamp that facilitates the design of a high frequency lighting circuit.

According to the invention of claim 3, in addition to surrounding the electrode which is arranged around the small diameter cylindrical portion of the translucent ceramics discharge vessel and is inserted into the small diameter cylindrical portion, the same potential as the counter electrode is provided. Since the mechanical strength of the small-diameter cylindrical portion is improved by including the starting auxiliary conductor, the base portion of the small-diameter cylindrical portion, that is, the above-mentioned boundary portion, is caused by the thermal stress due to the precursory minute discharge between the starting auxiliary conductor and the electrode. It is possible to provide a high-pressure discharge lamp that reduces defects such as cracks in the vicinity.

According to the invention of claim 4, in addition to surrounding the electrodes which are arranged around the pair of small-diameter cylindrical portions of the translucent ceramics discharge vessel and are inserted into the small-diameter cylindrical portions,
By having a pair of starting auxiliary conductors that have the same potential as the opposing electrodes and are asymmetrical to each other, the electrostatic capacitance between the asymmetrical starting auxiliary conductor and the electrodes is increased, and As a result of the relatively large precursory discharge current, the energy consumed for evaporation of the discharge medium increases, the heating of the electrode is suppressed by that amount, and blackening can be reduced, thereby providing a high-pressure discharge lamp.

According to the invention of claim 5, it is possible to provide an illumination device having the effects of claims 1 to 4.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of a high pressure discharge lamp of the present invention.

FIG. 2 is an explanatory view schematically showing a cross section of the same translucent ceramics discharge vessel.

FIG. 3 is a partially transparent front view showing a second embodiment of the high pressure discharge lamp of the present invention.

FIG. 4 is a partial sectional front view showing a light bulb shaped high pressure discharge lamp device as a third embodiment of a high pressure discharge lamp and a first embodiment of a lighting device of the present invention.

FIG. 5: High frequency lighting circuit mainly composed of a half bridge type high frequency inverter

FIG. 6 is a partial central cross-sectional front view showing a spotlight as a second embodiment of an illumination device of the present invention.

FIG. 7 is a front view showing a spotlight as a fourth embodiment of a high-pressure discharge lamp and a third embodiment of a lighting device of the present invention.

[Explanation of symbols]

1 ... Translucent ceramics discharge vessel 1a ... Surrounding part 1a1 ... cavity 1b ... Small diameter tube 1b1 ... through hole 2 ... Electrode 2a ... Shaft 2b ... 1st coil part 2c ... second coil section 3 ... Introduction conductor 4 ... Seal part CF: concave curved surface DP ... inflection point g ... Slight gap

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05B 41/24 H05B 41/24 L // F21Y 101: 00 F21Y 101: 00 F term (reference) 3K014 AA01 EA00 3K072 AA11 BA03 BB01 GA02 GB12 5C039 BA07 BB23 5C043 AA05 AA06 AA14 AA20 CC03 CD01 DD03 DD04 EA01

Claims (5)

[Claims] 1. A concave portion having a surrounding portion surrounding a discharge space and a small-diameter cylindrical portion communicating with both ends of the surrounding portion and integrally molded, and having a continuous outer surface at a boundary portion between the surrounding portion and the small-diameter cylindrical portion. A translucent ceramics discharge vessel having curved and discontinuous inflection points on the inner surface; and a translucent discharge at the tip of the translucent ceramics discharge vessel, which is inserted into a small-diameter cylindrical portion of the translucent ceramics discharge vessel. A pair of electrodes facing the surrounding part of the container; the tip is connected to the base end of the electrode, at least the middle part is sealed to the translucent discharge container, and the base end is exposed to the outside from the translucent discharge container. And a discharge medium sealed in a translucent ceramics discharge vessel. 2. The high pressure discharge lamp according to claim 1, wherein the translucent ceramics discharge container has an inner surface of a surrounding portion which is substantially spherical. 3. A starting auxiliary conductor which is arranged around the small diameter cylindrical portion of the translucent ceramics discharge vessel and surrounds an electrode which is inserted into the small diameter cylindrical portion, and which has the same potential as the counter electrode. The high pressure discharge lamp according to claim 1 or 2, wherein 4. A structure which surrounds an electrode which is disposed around a pair of small-diameter cylindrical portions of a translucent ceramics discharge vessel and which is inserted into the small-diameter cylindrical portion, and which has the same potential as the counter electrode and is asymmetrical to each other. 4. The high pressure discharge lamp according to claim 1, further comprising a pair of starting auxiliary conductors that are 5. A lighting device main body; a high pressure discharge lamp according to claim 1, which is supported by the lighting device main body; and a lighting circuit for activating the high pressure discharge lamp. Lighting device.