JP2005235659A - Fluorescent lamp and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluorescent lamp and a luminaire, which are high in safety and reliability because an abnormal discharge happening at the lamp lifetime end and the like can surely be forced to stop and so on, and which are easy to be manufactured. <P>SOLUTION: The fluorescent lamp comprises: a glass valve 2 having a valve outer diameter of 34 mm or less and a valve length of 1,300 mm or less; filament electrodes 6, 6 sealed up to the both ends of the glass valve; a phosphor layer 4 formed on the inside surface of the glass valve; a discharge medium sealed in inside the glass valve and including mercury; and getters 13 located in the neighborhood of the electrodes respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fluorescent lamp and a luminaire that are improved in safety by preventing abnormal overheating of an electrode rarely occurring at the end of the life of the fluorescent lamp.

  In general, when a fluorescent lamp having a filament electrode (hot cathode) coated with an emitter (electron emitting material) is exhausted at the end of its life, the discharge current of a half cycle using the electrode as a cathode decreases and the half of the discharge current decreases. Abnormal discharge phenomenon such as wave discharge occurs. This abnormal discharge phenomenon causes the lamp voltage to rise above the rated value, so that when the lamp is lit at the commercial frequency, the lamp is quickly turned off, but it tends to occur continuously in the case of high-frequency lighting. Further, the cathode fall voltage in a normal lighting state before the emitter is consumed is normally about 10V, but the cathode fall voltage after the emitter disappears increases to 40 to 70V. For this reason, high energy is input to the electrode in which the abnormal discharge phenomenon continues, and an abnormal temperature rise of the electrode part or the base may be caused.

  On the other hand, during the lighting of the fluorescent lamp, a filament material such as tungsten (W) that forms the filament electrode and a lead wire material such as nickel (Ni) that forms a pair of inner leads (wells) that support both ends of the filament are present. The scattering material accumulates on the top of the glass stem that seals the inner lead and its surroundings.

  Even when the filament electrode is melted, lighting is easy to continue in the case of high-frequency lighting, so that the discharge starting point shifts to the inner lead, and the abnormal discharge phenomenon is continued. If this phenomenon continues, as described above, the electrode part such as the inner lead and the glass stem melts at an abnormally high temperature, and further, such as melting of the base of the fluorescent lamp and the socket of the lighting device occurs. There is. Further, since the scattered material deposited on the top of the stem is conductive, there is a possibility that the filament current is energized and problems such as melting of the stem occur due to Joule heating.

As an example of a fluorescent lamp for solving this problem, a metal hydride such as hydrogen titanium having a decomposition temperature higher than the temperature at the time of normal lighting of the fluorescent lamp is applied to the surface of the glass stem. There has been proposed a method in which metal hydride is decomposed to release hydrogen gas into a lamp, and the lamp voltage is increased by increasing the concentration of hydrogen gas pressure to forcibly stop abnormal discharge (see Patent Document 1).
JP 2001-250503 A

  However, in the conventional fluorescent lamp described above, metal hydride must be applied to the surface of the glass stem so that hydrogen gas is not released during normal lighting, and hydrogen gas is reliably released into the bulb during abnormal discharge. Therefore, it is necessary to select the application position, the application amount, and the material and to manage the process, and there is a problem that manufacturing is not easy.

  That is, when the fluorescent lamp is manufactured, the glass stem is heated to a high temperature, so that the metal hydride may reach the decomposition temperature during the manufacturing, and hydrogen gas may be released therefrom. For this reason, process control such as strict temperature control at the time of manufacture is necessary.

  If the metal hydride application position is too close to the filament electrode, the metal hydride may reach a decomposition temperature and release hydrogen gas when the filament electrode is normally lit. In the above prior art, a structure is disclosed in which a getter material is provided in the vicinity of a metal hydride to adsorb hydrogen gas released during normal lighting. However, since it is considered that the amount of hydrogen gas released exceeds the gas adsorption capacity of the getter substance, it is difficult to say that this is a preferable improvement measure for preventing problems caused by the increase in the hydrogen gas concentration during normal lighting.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a fluorescent lamp and a lighting fixture that can reliably stop abnormal discharge at the end of the lamp life and can be easily manufactured. .

  The invention according to claim 1 includes a bulb having a tube outer diameter of 34 mm or less and a tube length of 1300 mm or less; a filament electrode sealed at both ends of the bulb; a phosphor layer formed on the inner surface; and mercury enclosed in the bulb And a getter disposed in the vicinity of the electrodes sealed at both ends of the bulb.

  In the present invention and each of the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified.

  The vicinity of the electrode where the getter is disposed means a position where the impure gas stored by the getter can be released under the influence of the temperature rise during abnormal discharge. The optimum position is in the vicinity of the filament electrode and does not hinder the discharge.

  Fluorescent lamps having a bulb outer diameter of more than 34 mm and a tube length longer than 1300 mm (for example, 110 W type fluorescent lamp “FLR110” having a tube outer diameter of 38 mm and a tube length of about 2370 mm, etc.) Even if there was an impure gas release, the impure gas concentration did not rise above the desired level due to the large volume of the bulb, and the lamp lighting maintenance voltage did not increase. On the other hand, in the case of a fluorescent lamp having a bulb with a tube outer diameter of 34 mm or less and a tube length of 1300 mm or less, if the impure gas is released from the getter due to an abnormal discharge phenomenon, the impure gas concentration is effectively increased and the lamp is kept on. The voltage rises. Accordingly, the lighting sustaining voltage of the fluorescent lamp rises so as to exceed the output voltage of the high frequency lighting circuit, so that the abnormal discharge phenomenon stops.

  The tube outer diameter of the valve is optimally 10 to 28 mm, and the tube length is preferably 500 to 1200 mm.

  According to a second aspect of the present invention, in the fluorescent lamp according to the first aspect, the getters are respectively disposed on a pair of metal rings surrounding the electrodes.

  A metal ring surrounds a pair of electrodes to capture the electrode scattering material that scatters from the electrode to its surroundings, and prevents the electrode scattering material from adhering to the tube wall and blackening the tube wall. is there.

  The invention according to claim 3 is the fluorescent lamp according to claim 1 or 2, wherein a mercury emitter is formed on at least one of the pair of metal rings.

  According to a fourth aspect of the present invention, there is provided an instrument main body; the fluorescent lamp according to any one of claims 1 to 3 disposed in the instrument main body; a high frequency that supplies high frequency lamp power to a pair of electrodes of the fluorescent lamp A lighting circuit; and a life detection circuit that reduces or stops the output of the high-frequency lighting circuit when it detects that the lamp voltage applied to the pair of electrodes of the fluorescent lamp has reached a predetermined value or more. It is the lighting fixture characterized by having.

  The main body of the fixture is of a direct ceiling type, a ceiling suspended type or a wall-mounted type, which may be equipped with a globe, shade, reflective shade, etc., with a fluorescent lamp exposed, with a light guide plate It may be.

  According to the present invention, since the temperature of the electrode rises at the end of the life of the fluorescent lamp, impure gas is released from the getter in the vicinity of the electrode, and the lamp voltage rises early, so that abnormal discharge such as the end of life lasts for a long time. Therefore, it is possible to provide a highly reliable fluorescent lamp and lighting apparatus that can prevent the abnormal discharge state from being turned on at an early stage.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same or corresponding parts are denoted by the same reference numerals.

  FIG. 1 is a partially cutaway longitudinal sectional view of a fluorescent lamp 1 according to a first embodiment of the present invention. As shown in FIG. 1, the fluorescent lamp 1 is a high-frequency lighting-only type 32W type “FHF32”, and has a glass outer diameter of 25.5 mm, a tube inner diameter of 24.0 mm, a wall thickness of 0.75 mm, and a tube length of about 1200 mm. A valve 2 is provided. A pair of glass stems 3 and 3 are airtightly attached to both end portions in the axial direction of the glass bulb 2d. Here, the tube length of the glass bulb 2 refers to the length from the outer end of one base 8 to the outer end of the other base 8.

  The glass bulb 2 is made of soft glass such as soda lime glass, and a phosphor film 4 such as a three-wavelength light emitting type is formed on almost the entire inner surface thereof, and a rare gas and mercury are enclosed in the inside as a discharge medium. Has been. The rare gas of the discharge medium includes argon (Ar), neon (Ne), krypton (Kr), etc., and argon (Ar) is used in this embodiment.

  The glass bulb 2 is made of soft glass such as soda lime glass or lead glass, but may be made of hard glass such as borosilicate glass or quartz glass. The wall thickness of the valve is preferably about 0.8 to 1.2 mm, but is not limited thereto.

  The phosphor constituting the phosphor layer 4 can be a known phosphor such as a three-wavelength phosphor or a halophosphate phosphor. However, the use of a three-wavelength phosphor is preferable from the viewpoint of luminous efficiency. preferable.

As the three-wavelength emission type phosphor, BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ as a blue phosphor having an emission peak wavelength near 450 nm, and (La, Ce) as a green phosphor having an emission peak wavelength near 540 nm. , Tb) PO ₄ , Y ₂ O ₃ : Eu ³⁺ can be used as a red phosphor having an emission peak wavelength near 610 nm, but is not limited thereto.

A protective film may be interposed between the inner surface of the glass bulb 2 and the phosphor layer 4. The protective film is preferably composed of metal oxide fine particles, and well-known materials such as alumina (Al ₂ O ₃ ) and silica (SiO ₂ ) can be used as the metal oxide fine particles.

  Amalgam may be enclosed in the valve. The amalgam is accommodated in a narrow tube (exhaust pipe) disposed on a stem sealed at the end of the glass bulb. The amalgam is fixed or stored in any of these positions by means of melting, mechanical holding or the like. Moreover, the amalgam may be accommodated so as to be movable in the valve. When the amalgam is disposed in the glass bulb, the fluorescent lamp is lit in an optimum state even when the ambient temperature is relatively high.

  Amalgam is an alloy of mercury and a material that forms an alloy with mercury. For example, an amalgam such as zinc-mercury may be encapsulated for quantitative encapsulation of mercury. The amalgam may have any shape such as a pellet shape, a column shape, or a plate shape.

  FIG. 2 is an enlarged cross-sectional view showing electrode portions attached to both ends of the fluorescent lamp shown in FIG.

  As shown in FIG. 2, each glass stem 3 has a pair of wells (lead wires) 5, 5 sealed in the axial direction, arranged in parallel at a predetermined interval, and extends to the inside of the glass bulb 2. Between the inner ends of the pair of wells 5 and 5, filament electrodes 6 and 6 are bridged and fixed respectively.

  The pair of electrodes 6 and 6 are hot cathode electrodes in which an emitter material is applied to a filament. In addition, when it is necessary to light the lamp at a high output, it is preferable to use a triple coil for the electrodes 6 and 6. Wells that support the electrodes 6 and 6 are sealed and supported by a flare stem, a button stem, a bead stem, a pinch seal portion, and the like.

  The glass stem 3 is integrally formed with a small exhaust pipe 7 at an intermediate portion between the pair of wells 5 and 5. The exhaust pipe 7 is sealed after the glass bulb 2 is sealed, and an exhaust hole 7 a for communicating the inside of the exhaust pipe 7 and the discharge space in the glass bulb 2 is formed in the side surface of the glass stem 3.

  A pair of bases 8 and 8 are fitted and fixed to the outer surfaces of both ends in the axial direction of the glass bulb 2 provided with these exhaust pipes 7, and the two bases 8 and 8 are connected to a pair of wells 5 and 5. A pair of base pins 9 and 9 are provided in a protruding manner.

  The cap pins 9 and 9 are electrical connection means for connecting to power supply means such as a socket of a lighting fixture. The base pins 9, 9 may be provided at positions away from both end portions of the glass bulb 2. Moreover, the bases 8 and 8 may be configured to exhibit a function as a holding unit by mechanical connection with the power supply unit.

  FIG. 3 is a perspective view showing a state before the electrode portions of FIG. 2 are provided at both ends of the glass bulb 2 of the fluorescent lamp 1.

As shown in FIG. 3, a support wire 10 is implanted in a substantially central portion of the glass stem 3 in a state of being electrically insulated from the wells 5 and 5. For the support wire 10, for example, a dumet wire having a thermal expansion coefficient difference of 20 × 10 ⁻⁷ cm / ° C. or less from the glass stem 3 is used. Thereby, since the thermal expansion coefficient of the support wire 10 approximates that of the glass stem 3, the thermal distortion of the glass stem 3 can be reduced, and the occurrence of cracks can be prevented.

  FIG. 4 is a perspective view showing the metal ring 11. An ellipse-shaped metal ring 11 is fixed to the tip of the support wire 10. The metal ring 11 is formed by a cylindrical ring in which a strip-shaped metal plate such as stainless steel (SUS), iron (Fe), nickel (Ni) or the like is formed in an oval or elliptical cross section. The metal ring 11 is attached to the support wire 10 so that its longitudinal direction is along the coil axis direction of the filament electrode 6 and the opening faces the center of the glass bulb 2. Further, the metal ring 11 surrounds the filament electrode 6 so as to form a required distance from the filament electrode 6. The metal ring 11 has a mercury emitter 12 disposed on the inner surface (filament electrode 6 side) and a getter 13 disposed on the outer surface. As the mercury emitter 12, for example, a mercury alloy (TiHg) made of an alloy powder of mercury (Hg) and titanium (Ti) is used in a layered manner.

  The mercury emitter 12 evacuates the inside of the glass bulb 2 and then heats the metal ring 11 from the outside of the glass bulb 2 to a predetermined temperature by induction heating. Mercury vapor is heated from the mercury emitter 12 to the glass bulb by the heating. It is made to discharge in 2 and to be enclosed. The mercury emitter 12 may be provided on each of the metal rings 11 and 11 provided on both ends of the bulb, but is provided only on one of the metal rings 11 and 11. There may be. However, it is necessary to provide the getter 13 on each of the metal rings 11 and 11 provided at both ends of the valve.

  The getter 13 is made of a fine powder of an alloy of zirconium and aluminum (ZrAl), for example, and is applied to the outer surface of the metal ring 11 in a strip shape, for example.

  The getter 13 is a substance that adsorbs and incorporates an impurity gas such as hydrogen in a bulb after being activated at a predetermined high temperature in a vacuum for a predetermined time. The getter 13 has an abnormally high temperature such as the end of the lamp life higher than the activation temperature. Sometimes it refers to a substance that releases again the impure gas that was occluded during activation. For example, a mixture containing Ti, Zr or Al such as ZrAl is preferable.

  The getter 13 is activated and has a high adsorption effect when the metal ring 11 is heated to a predetermined temperature by induction heating during the exhaust process of exhausting the glass bulb 2. That is, the getter 13 functions to suppress an impurity gas concentration in the bulb by adsorbing an impurity gas such as hydrogen gas in the glass bulb 2 in a normal state.

  By the way, the temperature in the vicinity of the electrode rises to, for example, 700 ° C. to 800 ° C. due to the continuation of the abnormal discharge phenomenon at the end of the life of the fluorescent lamp, and this temperature is higher than the activation temperature of the getter 13 at the time of manufacturing the fluorescent lamp. Therefore, if the abnormal discharge phenomenon continues, impure gas such as hydrogen gas occluded during activation is released from the getter 13, and the lamp sustaining voltage increases, and abnormal discharge can be stopped. I found that there was. As the getter 13, a non-evaporable getter other than a Zr—Al alloy is also applicable, and one kind of titanium (Ti), zirconium (Zr), aluminum (Al), vanadium (V) and iron (Fe) is used. It may be a metal or an alloy containing two or more of these as a main component.

  In addition, as shown in FIG. 5, the metal ring 11 itself is formed by, for example, connecting two long arc-shaped metal pieces 11a and 11b in the circumferential direction by caulking coupling of these locking tongue pieces 11c and 11d. You may form in a circular ring shape. In this case, the metal piece 11a can use GEMEDIS (trade name) manufactured by SAES. The metal piece 11a is formed by applying a mercury emitter 12 and a getter 13 to the front and back surfaces of a strip of iron (Fe). The metal pieces 11a and 11b are strips made of stainless steel (SUS), and the mercury emitter and getter are not applied.

  Since the fluorescent lamp 1 is configured as described above, after the glass bulb 2 is evacuated and sealed, the metal ring 11 is heated from the outside of the glass bulb 2 to a predetermined temperature by high-frequency induction heating, and the heating causes mercury. By heating the emitter 12, a predetermined amount of mercury vapor is released from the mercury emitter 12, while the getter 13 is activated by heating, and impure gas such as hydrogen gas in the glass bulb 2 is occluded by the getter 13. be able to.

  The fluorescent lamp 1 is lit by supplying a high frequency power of, for example, 10 KHz or more from a high frequency lighting circuit (not shown) to the pair of filament electrodes 6 and 6, but at the end of the lamp life, the pair of filament electrodes 6 , 6 may be consumed and the abnormal discharge phenomenon may be maintained.

  Thereby, although the electrode part of the fluorescent lamp 1 is abnormally heated, the metal ring 11 is also heated to a high temperature almost simultaneously, and the getter 13 is also heated to, for example, 700 ° C. to 800 ° C. For this purpose, an impure gas such as hydrogen gas that has been occluded during the activation and the subsequent adsorption action is released into the glass bulb 2.

  As a result, the concentration of impure gas in the glass bulb 2 is increased, and the lighting sustaining voltage of the lamp continues to rise so as to exceed the output voltage of the high-frequency lighting circuit, so that the abnormal discharge stops and the lamp is extinguished. As described above, it is possible to prevent the abnormal discharge phenomenon at the end of the life of the fluorescent lamp from continuing for a long period of time and the melting of the glass stem 3, the wells 5, the base 8, the socket of the lighting device, and the like.

  Thus, the metal ring 11 provided with the getter 13 is provided at a position near the electrode rather than the glass stem 3 and is formed of a metal having a high thermal conductivity. It reaches a higher temperature faster than the glass stem 3.

  Note that the getter 13 is not necessarily provided on the metal ring 11 and may be welded to, for example, the inner lead 5, the glass stem 3, or the inner lead as long as the impure gas can be released due to the influence of overheating during abnormal discharge. However, it is more effective to provide the getter 13 in the metal ring 11 than in the glass stem 3 in order to quickly release the impure gas during the abnormal discharge of the fluorescent lamp 1.

  Further, the temperature difference between the non-operating state in which the getter 13 occludes the impure gas (during normal lighting) and the operating state in which the occluded gas is released (during abnormal discharge) is higher than that of the glass stem 3. Therefore, by providing the getter 13 on a metal ring, the selection range when selecting the material of the getter 13 can be widened. For this reason, it is possible to prevent the getter 13 from releasing the occluded gas at a high temperature during the exhaust process of the glass bulb 2, so that strict temperature control is not required, and the ease of manufacturing the getter 13 and the cost are improved. Reduction can be achieved together.

  In addition, since the temperature range from the non-operating state to the operating state of the getter 13 can be increased, it is easy to set the temperature at which the getter 13 is reliably operated. For this reason, since the certainty that the impure gas occlusion operation and the occluded gas release operation of the getter 13 can be reliably performed can be improved, safety and reliability can be improved.

  In addition, since the electrode scattering material scattered from the filament electrode 6 toward the tube wall of the glass bulb 2 is captured by the metal ring 11 before being scattered to the tube wall, the electrode scattering material adheres to the tube wall. Blackening can be prevented or reduced. Note that the metal ring getter 13 does not necessarily have to be activated during the exhaust process, and even if it is a getter that does not activate, it can be stored at the end of its life if it has occluded impure gas. It was confirmed that it works well. Further, a 40 W type fluorescent lamp (model names “FL40” and “FLR40”) having a bulb outer diameter of 32.5 mm and a tube length of about 1200 mm is configured in the same manner as in the first embodiment, and is operated at high frequency. As a result, the abnormal discharge phenomenon at the end of the life did not continue for a long time, and the same effect as in the first embodiment was recognized.

  FIG. 6 is a side view of the lighting fixture 21 according to the second embodiment of the present invention. This luminaire 21 shows a state in which the fluorescent lamp 1 according to the first embodiment is mounted on a fixture main body 22 such as a direct ceiling type.

  The lighting fixture 21 is provided with a pair of sockets 23 and 23 for detachably mounting the pair of caps 8 and 8 of the fluorescent lamp 1 on one surface of the fixture main body 22, while the pair of sockets 23 and 23 are electrically connected. A high-frequency lighting circuit 24 that is connected to each other and supplies high-frequency power of, for example, 10 KHz or more is built in the instrument body 22. The high frequency lighting circuit 24 includes an end of life detection circuit 25.

  Note that the high-frequency lighting circuit 24 may be provided with switching means. The switching means may be divided into a mode in which the fluorescent lamp 1 is turned on with high efficiency and a mode in which the fluorescent lamp 1 is turned on with high output, or may be changed continuously between these modes. By switching the switching means of the lighting circuit 24, the lighting of the fluorescent lamp 1 is adjusted. For example, when the switching means is divided into a mode for lighting with high efficiency and a mode for lighting with high output, the fluorescent lamp can be used by appropriately selecting these modes according to the use conditions.

  The fluorescent lamp 1 is attached according to the shape of the main body of the lighting fixture 22 or the optical characteristics of the lighting fixture 21, and a plurality of fluorescent lamps having the same shape or different shapes are combined to change the arrangement height of the same plane or bulbs. Is mounted on the instrument body 22.

  The end of life detection circuit 25 has a function of detecting abnormal discharge by detecting that the lamp voltage applied to the pair of filament electrodes 6 and 6 of the fluorescent lamp 1 has risen to a predetermined value or more. When the end of life detection circuit detects an abnormal discharge of the fluorescent lamp 1, the high-frequency lighting circuit 24 stops the output operation and forcibly stops the abnormal discharge, or reduces the output to prevent sudden turn-off. Even in abnormal discharge, the fluorescent lamp operates so as to be dimly lit so that the temperature of the electrode portion does not increase excessively.

  Therefore, according to this luminaire 21, when the fluorescent lamp 1 is abnormally discharged due to the end of its life and rises to an abnormally high temperature, the getter 13 in the glass bulb 2 of the fluorescent lamp 1 is impure as described above. Release gas.

  Thereby, since the concentration of impure gas in the glass bulb 2 is increased and the discharge voltage is increased, the abnormal discharge is forcibly stopped or the output is reduced to prevent the temperature of the electrode portion from rising.

  That is, according to the second embodiment, at the end of the life of the fluorescent lamp 1, a double operation that combines the impure gas discharge action of the getter 13 of the fluorescent lamp 1 and the action of the life detection circuit 25 of the lighting fixture 21. Since the abnormal discharge phenomenon is prevented from continuing for a long time by the safe operation, the safety can be further improved.

  FIG. 7 is a graph showing the experimental results of examining the temperature change at the end of the base 8 of the fluorescent lamp 1 when an abnormal discharge at the end of life occurs in the fluorescent lamp 1 mounted on the lighting fixture 21. In the figure, symbol A indicates the temperature change at the end of the base 8 of the comparative fluorescent lamp having a mere stainless steel ring in which the metal ring 11 does not have the getter 13, and B indicates the getter 13 on the metal ring 11. The temperature change of the edge part of the nozzle | cap | die 8 of the fluorescent lamp of 1st Embodiment which provided 1 is shown.

  In the experiment, in order to reproduce the end of life due to the exhaustion of the emitter of the filament electrode 6 on one side of the fluorescent lamp 1, a fluorescent lamp in which the emitter is not applied to the filament electrode 6 on one side is produced, and this is used as a lighting fixture. The lighting test was carried out by attaching to No. 21. Both fluorescent lamps were lit by half-wave discharge immediately after the start of lighting.

  As a result, in the comparative fluorescent lamp having no getter 13 in the metal ring 11, the base 8 rises to a temperature exceeding about 230 ° C. after the lighting time has passed 400 seconds as shown by the curve A in FIG. After that, the temperature has dropped (dotted line part). This indicates that the half-wave discharge is continued, the temperature of the electrode portion rises excessively, the stem melts, the inside of the bulb leaks, and finally the light is extinguished and the temperature is lowered in the vicinity of about 460 seconds.

  On the other hand, in the fluorescent lamp 1 according to the first embodiment in which the getter 13 is provided on the metal ring 11, the getter is also heated by the abnormal heat generation of the electrode due to the half-wave discharge, and the impurity gas is released from the getter and the lamp voltage is increased. Since it continues to rise, after the lighting time has passed 200 seconds, the life detection circuit of the high-frequency lighting circuit operates to detect the end of life and reduce the output. For this reason, since the temperature of the electrode portion does not rise excessively after 200 seconds, the base 8 only rises to about 120 ° C., and the temperature rises to about ½ or less of the base temperature of the comparative fluorescent lamp. Can be suppressed. For this reason, melting of the glass stem 3, the wells 5, the base 8, and the socket 23 can be prevented in advance.

  Therefore, when the fluorescent lamp 1 according to the first embodiment is turned on by the lighting fixture 21 according to the second embodiment, the glass stem 3, the wells 5, the base 8 of the fluorescent lamp 1 even at the end of the life of the fluorescent lamp 1. Since the melting of the socket 23 and the like can be prevented, safety can be improved.

1 is a partially cutaway longitudinal sectional view of a fluorescent lamp according to Embodiment 1 of the present invention. FIG. 2 is a side sectional view of one electrode end portion shown in FIG. 1. The perspective view of one electrode mount shown in FIG. FIG. 4 is a perspective view of the metal ring shown in FIG. 3. The perspective view of the other Example of metal rings shown in FIG. The side view of the state which mounted | wore the irradiation lamp which concerns on Example 2 of this invention with the fluorescent lamp concerning Example 1. FIG. The graph which shows the temperature change of the nozzle | cap | die of a fluorescent lamp when the fluorescent lamp of the end of life shown in FIG. 1 is lighted with the lighting fixture shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Fluorescent lamp, 2 ... Glass bulb, 3 ... Glass stem, 4 ... Phosphor layer, 6 ... Filament electrode, 11 ... Metal ring, 12 ... Mercury emitter, 13 ... Getter, 21 ... Lighting equipment, 22 ... Equipment Main body, 23 ... socket, 24 ... high frequency lighting circuit.

Claims (4)

A valve having a tube outer diameter of 34 mm or less and a tube length of 1300 mm or less;
A filament electrode sealed at both ends of the bulb;
A phosphor layer formed on the inner surface;
A discharge medium containing mercury enclosed in the bulb;
Getters disposed in the vicinity of electrodes sealed at both ends of the bulb;
A fluorescent lamp characterized by comprising: 2. The fluorescent lamp according to claim 1, wherein the getter is disposed on a pair of metal rings surrounding the electrodes. 3. The fluorescent lamp according to claim 1, wherein a mercury emitter is formed on at least one of the pair of metal rings. An instrument body;
The fluorescent lamp according to any one of claims 1 to 3, which is disposed in the instrument body;
A high-frequency lighting circuit for supplying high-frequency lamp power to a pair of electrodes of the fluorescent lamp;
An end-of-life detection circuit that lowers or stops the output of the high-frequency lighting circuit when it detects that the lamp voltage applied to the pair of electrodes of the fluorescent lamp has reached a predetermined value or higher;
The lighting fixture characterized by comprising.

Images