JP2006294270A - Fluorescent lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric bulb type fluorescent lamp hardly causing deterioration of a luminous flux maintenance factor due to globe yellowing. <P>SOLUTION: The fluorescent lamp 1 is composed of an luminous tube 10 having an electrode 15 on an end part 11, a holder 20 supporting the end part of the luminous tube 10 and a globe 40 housing the luminous tube 10, and the above holder 20 is made of liquid crystal polymer resin. And the luminous tube 10 has a double spiral shape and a tube axis X of its end part is inclined against a spiral axis Z of the luminous tube 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluorescent lamp.

In the age of energy saving, light bulb-type fluorescent lamps have been widely used as energy-saving light sources to replace general light bulbs.
In recent years, the development of a double spiral arc tube has made it possible to make a bulb-type fluorescent lamp as large as a general bulb. For this reason, the application rate of light bulb-type fluorescent lamps to general light bulbs is increasing, and the replacement of general light bulbs with light bulb-type fluorescent lamps is progressing.

By the way, arc tubes A and arc tubes B described below are known as arc tubes of a bulb-type fluorescent lamp having a double spiral arc tube.
In the arc tube A, the tube axis at the end of the arc tube is substantially parallel to the spiral axis of the arc tube (Non-Patent Document 1).
On the other hand, in the arc tube B, the tube axis at the end of the arc tube is inclined rather than parallel to the helical axis of the arc tube (Patent Document 1). Since the arc tube B has substantially no end of the arc tube in the arc tube A (the portion where the tube axis is substantially parallel to the spiral axis), the entire length of the lamp can be shortened, and the bulb shape The fluorescent lamp can be further miniaturized.

For example, a 12W bulb-type fluorescent lamp equipped with an E26-type base and a globe, which is a substitute for a 60W bulb, has a small globe outer diameter of 55 mm, a total lamp length of 110 mm, a luminous flux of 810 lm, and a rated life of 6000 hrs. It has quality lamp characteristics.
In such a 12W bulb-type fluorescent lamp, since the end portion of the arc tube in which the electrode that becomes high temperature by lighting is disposed is held by the holder, the holder is likely to become high temperature. For this reason, the holder is formed of a so-called flame-retardant PET (polyethylene terephthalate) resin (heat-resistant temperature 185 ° C., member color is white) (Patent Document 2).
Notification of CN3255774D Japanese Patent Laid-Open No. 9-17378 JP 2004-95403 A

Next, the inventor tackled the development and commercialization of a 22 W bulb-type fluorescent lamp equipped with an E26-type base and a globe as an alternative to a 100 W bulb.
The 22W bulb-type fluorescent lamp was manufactured in a configuration according to the 12W bulb-type fluorescent lamp. That is, it was produced by using the above-mentioned arc tube B using a double spiral arc tube that was longer than the 12 W bulb-type fluorescent lamp. The holder was made of flame retardant PET resin. Thereby, for example, a 22W bulb-type fluorescent lamp having a small globe with an outer diameter of 60 mm, a total lamp length of 137 mm, and a luminous flux of 1520 lm was obtained.

However, when the life test of the 22W bulb-type fluorescent lamp was conducted, there was a problem that the inner surface of the globe was yellowed by lighting for about 2000 hrs. Such a phenomenon of yellowing of the globe is an abnormal discoloration that is undesirable in terms of lamp appearance, and is a serious quality problem that lowers the light transmittance of the globe and greatly reduces the luminous flux maintenance factor.
In addition, the inventors examined the yellowing of the 12W bulb-type fluorescent lamp carefully. As a result, in the case where the lighting time was 6000 hrs or more, similar yellowing was observed although it was hardly noticeable. In other words, yellowing is a phenomenon peculiar to the above-mentioned fluorescent lamp, and it can be said that a problem has become apparent particularly in a high-watt 22W bulb-type fluorescent lamp having severe lighting conditions.

  In view of the above problems, an object of the present invention is to provide a fluorescent lamp in which a decrease in luminous flux maintenance rate due to yellowing of a globe hardly occurs.

In order to achieve the above object, a fluorescent lamp according to the present invention as set forth in claim 1 is an arc tube provided with an electrode at an end, a holder for holding the end of the arc tube, and a globe including the arc tube. And the holder is formed of a liquid crystal polymer resin.
A fluorescent lamp according to a second aspect of the present invention is the fluorescent lamp according to the first aspect, wherein an end of the arc tube is accommodated in the holder.

  Furthermore, the fluorescent lamp according to the present invention of claim 3 is the fluorescent lamp of claim 1 or 2, wherein the arc tube has a double helix shape, and the tube axis at the end of the arc tube has the axis. The structure is inclined with respect to the helical axis of the arc tube.

  In the fluorescent lamp having the configuration of the present invention, since the holder is made of a liquid crystal polymer resin, even if the heat of the electrode arranged at the end of the arc tube propagates to the holder and the holder becomes high temperature. , Gas is not easily generated from the holder. Therefore, yellowing inside the globe due to the gas can be suppressed, and a decrease in luminous flux maintenance factor of the fluorescent lamp can be suppressed.

Particularly, in the fluorescent lamp in which the end of the arc tube is housed in the holder, the portion of the coil having the highest temperature among the electrodes is close to the holder, so that the holder is likely to be hotter. Therefore, the configuration of the present invention is effective in that gas is not easily generated from the holder even when the temperature of the holder becomes high.
In addition, when the arc tube has a double spiral shape and the end portion of the arc tube is formed to form an oblique angle with respect to the spiral axis of the arc tube, the end portion is inclined to the holder. Because it is inserted, the end penetrates deeper into the holder. Accordingly, the configuration of the present invention is particularly effective because the coil of the electrode is more easily disposed near the holder, and the holder is likely to have a higher temperature.

Hereinafter, fluorescent lamps according to embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partially broken front view showing an overall configuration of a fluorescent lamp according to an embodiment of the present invention, and FIG. 2 is an exploded view of the fluorescent lamp.
As shown in FIGS. 1 and 2, a fluorescent lamp 1 according to an embodiment of the present invention is a 22 W bulb-type fluorescent lamp for 100 W bulb replacement, and has a total length of 137.0 mm. The fluorescent lamp 1 includes an arc tube 10, a holder 20 that holds the end 11 of the arc tube 10, an electronic ballast 30, a globe 40, a case 50, and an E26-type base 60.

FIG. 3 is a partially broken front view showing the arc tube.
The arc tube 10 has a double spiral shape. Specifically, as shown in FIG. 3, the arc tube 10 has a double helix with a spiral axis Z as a glass tube having a tube outer diameter of 8.5 mm, a tube inner diameter of 6.9 mm, and a tube length of 86.0 mm. The container 12 is formed by turning it into a shape. The number of turns of the double spiral of the arc tube 10 is 6.75, and the outer diameter of the arc tube 10 is 41.5 mm. The container 12 is made of soft glass (strontium barium silicate glass).

In the arc tube 10, the tube axis X of the end 11 is inclined at an inclination angle α with respect to the helical axis Z of the arc tube 10 (inclination angle α is about 75 °). That is, the fluorescent lamp 1 in the present embodiment uses the above-described arc tube B for miniaturization. The inclination angle α between the tube axis X of the end portion 11 and the spiral axis Z of the arc tube 10 is greater than 0 ° and smaller than 90 °.
The arc tube 10 includes a tungsten filament coil 13 (hereinafter referred to as a coil 13) filled with an electron emitting substance at an end portion 11 and a pair of lead wires 14a and 14b for holding the coil 13 in a bead glass mount system. The electrode 15 which consists of is provided.

Specifically, the electrode 15 includes lead wires 14a and 14b and a coil 13 installed on the lead wires 14a and 14b. The coil 13 is disposed inside the container 12, and the lead wires 14a and 14b are provided in the container. It is sealed and held at 12 end portions (portions constituting the end portion 11 of the arc tube 10).
One end 11 is sealed with an electrode 15 and an exhaust pipe 16 (the front end is sealed after the arc tube 10 is exhausted). The distance between the electrodes is 700 mm, and the discharge path has a double spiral shape.

A rare earth phosphor 17 is applied to the main inner surface of the arc tube 10. The rare earth phosphor 17 includes a red light emitting phosphor (Y ₂ O ₃ : Eu), a green light emitting phosphor (LaPO ₄ : Ce, Tb), and a blue light emitting phosphor (BaMg ₂ Al ₁₆ O ₂₇ : Eu, Mn). Mixed.
In the tube of the arc tube 10, about 5 mg of mercury and 500 Pa of argon gas Ar are enclosed as a buffer gas.

The distal end portion 18 of the arc tube 10 is expanded into a convex shape, and becomes the coldest spot that defines the mercury vapor pressure in the tube when the lamp is lit. Further, a space between the distal end portion 18 of the arc tube 18 and the distal end portion 41 of the globe 40 is filled with a heat conductive medium 42 made of a transparent silicone resin.
The tip 18 is adjusted to 55 to 65 ° C. when the lamp is turned on, and an optimum mercury vapor pressure in the tube can be obtained in terms of efficiency. Note that the vicinity of the tip 18 of the arc tube 10 has a larger tube diameter than other portions.

4A and 4B are diagrams showing a holder, in which FIG. 4A is a front view and FIG. 4B is a plan view. FIG. 5 is a perspective view showing an attached state of the arc tube.
As shown in FIGS. 4A and 4B, the holder 20 includes a substantially circular resin substrate 21 (diameter 43.0 mm, wall thickness 0.9 mm) for holding an arc tube and a resin for holding an electronic circuit board. A peripheral plate 22 (edge height 10.0 mm, wall thickness 0.9 mm) is provided.

The resin substrate 21 is provided with a pair of openings 23 a and 23 b into which the end portion 11 of the arc tube 10 is inserted. The opening surfaces of the openings 23a and 23b are inclined at an inclination angle β with respect to the helical axis Z of the arc tube 10 (inclination angle β is about 14 °).
Guide grooves 24 a and 24 b and guide lids 25 a and 25 b are formed in the resin substrate 21. The guide grooves 24a and 24b and the guide lids 25a and 25b are connected to the peripheral edges of the openings 23a and 23b, and are inclined with respect to the spiral axis Z at an oblique angle α. The bottom surfaces of the guide grooves 24 a and 24 b and the ceiling surfaces of the guide lids 25 a and 25 b are curved according to the outer shape of the end portion 11. Therefore, when the end portion 11 of the arc tube 10 is rotated clockwise, the end portion 11 can be smoothly inserted into the openings 23 a and 23 b of the resin substrate 21.

An end 11 of the arc tube 10 is held by a holder 20. Specifically, the end portion 11 of the arc tube 10 is inserted into the openings 23a and 23b of the resin substrate 21 and is fixed by a silicon resin 26 inside the holder 20 as shown in FIG.
Here, the electrode 15 sealed at the end 11 of the arc tube 10 is in a state where the entire electrode 15 is accommodated in the holder 20. That is, the coil 13 having the largest heat generation amount in the electrode 15 is accommodated in the holder 20. That is, the end 11 of the arc tube 10 in which the electrode 15 is located is disposed in a space formed by the holder 20 and the case 50.

As described above, when the coil 13 is accommodated in the holder 20, the heat of the coil 13 propagates to the holder 20, and the holder 20 is likely to have a high temperature. In addition, when the electrode 15 is located in a space formed by the holder 20 and the case 50, the heat of the electrode is trapped in the space, and the holder 20 is likely to have a higher temperature.
In order to reduce the size of the fluorescent lamp 1, it is preferable to insert the end portion 11 of the arc tube 10 deeply into the holder 20. In that respect, the arc tube B can be inserted deeply into the holder 20 because the tube axis X of the end portion 11 of the arc tube 10 is inclined with respect to the spiral axis Z. Note that the end portion 11 of the arc tube 10 hardly contributes to the light flux, so that the light flux of the fluorescent lamp 1 is not easily lowered.

On the other hand, when the end portion 11 of the arc tube 10 is inserted deeply into the holder 20, the coil 13 of the electrode 15 sealed to the end portion 11 is disposed inside the holder 20. If it does so, the holder 20 will become high temperature easily.
The electronic ballast 30 is a so-called series inverter type electronic ballast, and includes an electronic circuit component 31 and a circuit board 32 on which the electronic circuit component 31 is mounted. Six holding pieces 27 a to 27 f are attached to the resin peripheral plate 22 of the holder 20, and the electronic ballast 30 is attached to the holder 20 by fitting the circuit board 32 to the holding pieces 27 a to 27 f. It is installed.

In order to suppress an excessive temperature rise of the electronic circuit component 31 when the lamp is lit, a gap of about 17 mm is provided between the circuit board 32 of the electronic ballast 30 and the resin board 21 of the holder 20. Yes.
The globe 40 has an eggplant shape having a maximum outer diameter of 60 mm and includes the arc tube 10. Here, the inclusion is not limited to the case where almost the entire arc tube 10 is within the globe 40 as in the fluorescent lamp 1 of the present embodiment, and a part of the arc tube 10 is part of the globe. The case where it is not within 40 is also included. For example, part or all of the end portion 11 accommodated in the holder 20 of the arc tube 10 does not necessarily need to be accommodated in the globe 40. That is, only the portion of the arc tube 10 outside the holder 20 may be in a state where it is housed inside the globe 40.

  The case 50 is a cylinder made of PBT (polybutylene terephthalate) resin (heat-resistant temperature 135 ° C.), has a total length of 45.0 mm, a wall thickness of 0.9 mm, and an outer diameter of the case opening on the arc tube side. Is 50.0 mm. The case 50 is attached to the holder 20 so as to enclose the electronic ballast 30 attached to the holder 20 and to be fitted to the resin peripheral plate 22 of the holder 20. A base 60 is attached to the end of the case 50 opposite to the opening on the arc tube side.

The fluorescent lamp 1 according to the present embodiment has a lamp characteristic suitable for 100 W bulb replacement with an efficiency of 69.1 lm / W with a luminous flux of 1520 lm at a lamp input 22 W.
In the fluorescent lamp 1 according to the present embodiment, the holder 20 that holds the arc tube 10 is formed of a liquid crystal polymer resin (heat resistant temperature 220 ° C.) having a heat resistant temperature higher than that of the PET resin (heat resistant temperature 185 ° C.). Since the heat-resistant temperature of the liquid crystal polymer resin is high, no gas is generated from the holder 20 even when the temperature of the holder 20 rises when the lamp is turned on, and yellowing of the globe 40 can be suppressed.

When the life test was performed on the fluorescent lamp 1 according to the present embodiment, the yellowing phenomenon on the inner surface 43 of the globe 40 was not observed even after the rated life of 6000 hrs.
As alternative materials for PET resin, PPS (polyphenylene sulfide) resin, PEI (polyetherimide) resin, and the like have been considered. However, since PPS resin has a complicated mold and has a black material color, fluorescent lamp 1 This is not suitable for the holder 20, and the mold of PEI resin is complicated. On the other hand, the liquid crystal polymer resin can be easily molded while using a conventional mold. In addition, since the strength is strong, there is an advantage that the holding pieces 27a to 27f of the holder 20 are not easily broken.

Specifically, Vectra (registered trademark) manufactured by Polyplastics Co., Ltd., which is a wholly aromatic polyester, was used as the liquid crystal polymer resin.
FIG. 6 is a diagram comparing the luminous flux maintenance factor C of the fluorescent lamp 1 with the liquid crystal polymer resin holder 20 and the luminous flux maintenance factor D of the fluorescent lamp with the PET resin holder as a comparative product.

  As shown in FIG. 6, the luminous flux maintenance rate C of the fluorescent lamp 1 with the liquid crystal polymer resin holder 20 is about 78% at 6000 hrs, for example, whereas the luminous flux maintenance of the fluorescent lamp with the PET resin holder is about 78%. The rate D was about 64%, and it was confirmed that the luminous flux maintenance rate of the fluorescent lamp according to the present invention was remarkably improved as compared with the comparative fluorescent lamp. Note that the 22W bulb-type fluorescent lamp used as a comparative product has the same configuration as the 22W bulb-type fluorescent lamp 1 according to the present embodiment except that the holder is made of PET resin.

The reason why the luminous flux maintenance factor of the comparative fluorescent lamp is low is that the globe is yellowed. The inventor has reached the present invention by ascertaining the cause of yellowing of the globe through experiments and finding a solution.
In order to determine the cause of yellowing, first, a 22 W bulb-type fluorescent lamp using a holder made of PET resin was turned on with a tube input 22 W, and the surface temperature of the resin substrate of the holder was measured. As a result, in the holder, the temperature at the center of the resin substrate and the temperature at the periphery of the opening into which the end of the arc tube was inserted were about 150 ° C., respectively. However, since the temperature of each part is lower than 185 ° C. which is the heat resistant temperature of the PET resin, it was difficult to think that the temperature of each part was the cause of yellowing at the beginning of the experiment.

However, as the experiment proceeded, it was found that the temperature of each part reached a temperature at which some substance contained in the PET resin was evaporated. And we came to the conclusion that some substance would be a flame retardant. That is, it came to the conclusion that the substance produced by the evaporation of the flame retardant adheres to the inner surface of the globe as a gas and causes yellowing.
Therefore, as a result of various investigations on alternative materials to PET resin, a liquid crystal polymer resin having higher heat resistance than PET resin and having a higher thermal decomposition temperature was found, and the liquid crystal polymer resin generates very little gas. confirmed.

  As described above, in the small fluorescent lamp 1 in which the main members such as the small luminous tube 10 such as the double helix and the small electronic ballast 30, the holder 20 and the case 50 corresponding thereto are assembled, the holder If 20 is formed of a liquid crystal polymer resin, yellowing of the globe 40 can be suppressed, and a decrease in the luminous flux maintenance factor of the fluorescent lamp 1 can be suppressed, so that a high-quality and small-sized bulb-type fluorescent lamp 1 can be obtained. .

Although the fluorescent lamp according to the present invention has been specifically described above based on the embodiment, the fluorescent lamp according to the present invention is not limited to the above-described embodiment. For example, the following modifications can be considered.
(1) Although the above-described arc tube B is used in the fluorescent lamp 1 according to the embodiment, the arc tube A may be used in the fluorescent lamp according to the present invention.

FIG. 7 is a partially broken front view showing the fluorescent lamp according to the first modification. As shown in FIG. 7, a light bulb-type fluorescent lamp 100 according to Modification 1 is a fluorescent lamp using an arc tube A, which is a double spiral arc tube 110, a holder 120 made of a liquid crystal polymer resin, an electronic stability A vessel 130, a globe 140, a case 150, and an E26-type base 160 are provided.
In the fluorescent lamp 100 according to the modified example 1, the tube axis of the end portion 111 of the arc tube 110 is substantially parallel to the spiral axis Z of the arc tube 10, and the end portion 111 is inserted vertically into the holder 120. ing.

(2) The fluorescent lamp according to the present invention can be applied to a fluorescent lamp other than a bulb-type fluorescent lamp, for example, a fluorescent lamp (compact lamp) as shown in FIG.
FIG. 8 is a partially broken front view showing a fluorescent lamp according to Modification 2. The fluorescent lamp 200 includes a double spiral arc tube 210, a holder 220 made of a liquid crystal polymer resin, a globe 240, a case 250, and a base 260 (for example, GX10q type). The fluorescent lamp 200 according to the modified example 2 and the fluorescent lamp 1 according to the present embodiment are such that the electronic ballast is not accommodated in the internal space formed by the holder 220 and the case 240, and the shape of the base 260 is general. It is very different in that it is not a screw cap used for a light bulb.

  (3) The arc tube of the fluorescent lamp is not limited to a double spiral shape, and may have another shape. Examples of other shapes include, for example, a U-shape formed by bending one glass tube, and a so-called “kura shape” formed by further bending the U-shaped glass tube, The glass tube bent into a U-shape may have a shape formed by combining a plurality of, for example, two or three glass tubes.

  In addition, although it is effective in a bulb-type fluorescent lamp in which an arc tube end portion having an electrode is positioned inside the holder, the arc tube end portion is not necessarily housed in the holder, and the end portion is not included in the holder. You may hold | maintain in the state located outside the holder. Further, the arc tube may be of a type in which the electrode is not located inside the holder but located outside the holder.

  It can be used for fluorescent lamps in which the arc tube is held by a holder and enclosed in a globe.

The partially broken front view which shows the whole structure of the fluorescent lamp which concerns on one Embodiment of this invention Exploded view of fluorescent lamp Partially broken front view showing arc tube It is a figure which shows a holder, Comprising: Fig.4 (a) is a front view, FIG.4 (b) is a top view The perspective view which shows the attachment state of an arc tube Comparison of luminous flux maintenance rates between a fluorescent lamp with a liquid crystal polymer resin holder and a fluorescent lamp with a PET resin holder Partially broken front view showing a fluorescent lamp according to Modification 1 Partially broken front view showing a fluorescent lamp according to Modification 2

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fluorescent lamp 10 Arc tube 11 End 15 Electrode 20 Holder 40 Globe

Claims (3)

An arc tube provided with an electrode at an end; a holder for holding the end of the arc tube; and a glove enclosing the arc tube;
A fluorescent lamp characterized in that the holder is made of a liquid crystal polymer resin.   The fluorescent lamp according to claim 1, wherein an end of the arc tube is accommodated in the holder.   The fluorescent tube according to claim 1 or 2, wherein the arc tube has a double spiral shape, and a tube axis at an end of the arc tube is inclined with respect to a spiral axis of the arc tube. lamp.

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