KR20100062969A - Electrode pin for discharge lamp and method for producing the same, electrode structure, cold cathode fluorescent lamp and method for manufacturing the same, illuminating device, and liquid crystal display device - Google Patents

Abstract

Disclosed is an electrode pin (22) for discharge lamps, which is an electrode pin to be sealingly attached to an end portion (10a) of a glass bulb (10). This electrode pin (22) for discharge lamps comprises an electrode pin main body and a groove (30) which is formed in the surface of the electrode pin main body at a position sealingly attached to the end portion (10a) of the glass bulb (10) so that it lies across a line extending along the longitudinal direction (35) of the electrode pin main body.

Description

ELECTRODE PIN FOR DISCHARGE LAMP AND METHOD FOR PRODUCING THE SAME, ELECTRODE STRUCTURE, COLD CATHODE FLUORESCENT LAMP AND METHOD FOR MANUFACTURING THE SAME, ILLUMINATING DEVICE, AND LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to an electrode pin for a discharge lamp, a manufacturing method thereof, an electrode structure, a cold cathode fluorescent lamp, a manufacturing method thereof, an illumination device, and a liquid crystal display device.

Currently, a cold cathode fluorescent lamp (CCFL) is mainly employed as a light source of a backlight unit of a liquid crystal display device. The electrode part of a cold cathode fluorescent lamp consists of an electrode part, an electrode pin (sealing line part), and an external lead wire (for example, refer patent document 1). In recent years, cold-cathode fluorescent lamps are longer (1000 [mm] or more in the case of longer) and thinner (outer diameter 2 [mm] in case of the thinner) due to the demand for larger, thinner, higher luminance, and power saving in LCD televisions. ], Brighter and more efficient.

Patent Document 1: Japanese Patent Application Laid-Open No. 2004-234891

The electrode pin (sealing rod) of the electrode part in a cold cathode fluorescent lamp consists of a tungsten rod. Since tungsten has a high melting point, it cannot be formed by casting or the like, and is produced by a so-called powder metallurgy method in which a powder is molded and sintered. Although this sintered compact is formed in rod shape by swaging process or wire drawing process, a longitudinal crack and a crack are likely to generate | occur | produce during the process.

If such cracks or cracks in the longitudinal direction are present in the electrode pins, they are not completely sealed by the glass, and through these defects, air flows into the tube of the discharge lamp, which causes a product defect. Usually, such defective electrode pins are essentially excluded by inspection.

However, even if the defect rate can be reduced to an error of several [ppm] orders by the inspection, the error value of the defective rate as a backlight becomes large because the cold cathode fluorescent lamps are used for the backlight several by several. Recently, liquid crystal displays are used not only for PC monitors but also for many televisions, and high reliability is required to withstand long hours of use for tens of thousands of hours.

On the other hand, cold cathode fluorescent lamps are required to be manufactured at low cost, and there is a situation in which a long lifetime and high reliability must be satisfied without using complicated structures or expensive members. As a result of earnestly examining under such a situation, the inventors of the present invention have found a configuration that can realize a simple configuration, a long service life, and high reliability, and have come to the present invention.

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above problems, and it is mainly to provide an electrode pin for a discharge lamp having excellent reliability, a method for manufacturing the same, an electrode structure, a cold cathode fluorescent lamp and a method for manufacturing the same, an illumination device, and a liquid crystal display device. The purpose.

In order to achieve the above object, the present invention adopts the following configurations.

[Electrode pin for discharge lamp]

The electrode pin for cold cathode discharge lamps of this invention is an electrode pin for discharge lamps sealed by the edge part of a glass bulb. And the electrode pin for discharge lamps of this invention is provided with the electrode pin main body and the groove | channel which sits along the line along the longitudinal direction of the said electrode pin main body in the place which seals and attaches to the edge part of the said glass bulb among the surface of the said electrode pin main body. . Here, as a specific example of the groove, it is possible to adopt a configuration of turning around the axis of the electrode pin body in a substantially rounded state.

In the electrode pin for cold cathode discharge lamps of the present invention, a configuration in which the groove is formed in a spiral shape on the surface of the electrode pin body can be adopted.

In the electrode pin for a cold cathode discharge lamp of the present invention, a configuration in which the spiral groove is formed at least 2 [rotation] on the surface of the electrode pin body can be adopted.

In addition, in the electrode pin for cold cathode discharge lamp of the present invention, a configuration in which the groove is formed in an annular shape in which one end and the other end are connected on the surface of the electrode pin body can be adopted.

In the electrode pin for a cold cathode discharge lamp of the present invention, a configuration in which two or more of the annular grooves are formed on the surface of the electrode pin body can be adopted.

In addition, the electrode pin for a cold cathode discharge lamp of the present invention includes a recess in which the groove is concave than the surface of the electrode pin body, and a convex portion connected to the recess and convex than the surface of the electrode pin body. The structure which is carried out can be employ | adopted.

In addition, in the electrode pin for cold cathode discharge lamps of the present invention, it is possible to adopt a configuration that is created by stretching by swaging or wire drawing.

Moreover, in the electrode pin for cold cathode discharge lamps of the present invention, a structure composed of tungsten (W) or molybdenum (Mo) can be adopted.

In addition, in the electrode pin for cold cathode discharge lamps of the present invention, a configuration composed of an alloy of iron (Fe) and nickel (Ni) can be adopted.

In the electrode pin for a cold cathode discharge lamp of the present invention, the groove may be formed by laser processing.

Moreover, in the electrode pin for cold cathode discharge lamps of the said invention, the structure which the lead wire is connected to the one end part of the said electrode pin main body can be employ | adopted.

In the electrode pin for a cold cathode discharge lamp of the present invention, a configuration in which the lead wire is made of nickel can be adopted.

Electrode Structure

The electrode structure of this invention has the electrode pin for discharge lamps of this invention, the lead wire is connected to the one end part of the electrode pin main body, and the structure which the cup electrode is connected to the other end can be employ | adopted.

Moreover, in the electrode structure of the said invention, the structure by which the glass bead is affixed on the surface of the said electrode pin main body can be employ | adopted.

Cold cathode fluorescent lamp

The cold cathode fluorescent lamp of the present invention comprises a glass bulb, a phosphor layer formed on an inner surface of the glass bulb, and an electrode pin for a discharge lamp of the present invention.

In the cold cathode fluorescent lamp of the present invention, a configuration in which the glass bulb is made of borosilicate glass can be adopted.

[Lighting device]

The lighting apparatus of this invention is equipped with the cold cathode fluorescent lamp of the said invention, It is characterized by the above-mentioned.

[LCD]

The liquid crystal display device of the present invention is provided with the above-described lighting device of the present invention.

[Manufacturing method of electrode pin for discharge lamp]

The manufacturing method of the electrode pin for discharge lamp of this invention is a manufacturing method of the electrode pin for cold cathode discharge lamps, The process (a) of preparing an electrode pin main body, and the longitudinal direction of the said electrode pin main body on the surface of the said electrode pin main body. The step (b) of forming a groove to sit the line according to. Here, in the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the groove which turns in the state which rotates substantially one round about an axis as a specific example of a recessed part can be employ | adopted.

In the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the said process (b) can be employ | adopted that it is performed by a laser processing method.

Moreover, in the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the structure which forms said groove | channel in the shape of a spiral can be employ | adopted, rotating the said electrode pin main body in the rotational axis.

In the method for manufacturing an electrode pin for a cold cathode discharge lamp of the present invention, the groove is formed in an annular shape in which one end and the other end are connected while rotating the electrode pin main body in the longitudinal axis of the rotary shaft. It can be adopted.

Moreover, in the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the said process (a) consists of a sub process which extends the metal material which comprises an electrode pin main body by swaging process or wire drawing process. Can be adopted.

Moreover, in the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the material which comprises the said electrode pin main body can adopt the structure which is tungsten or molybdenum.

[Manufacturing Method of Cold Cathode Fluorescent Lamp]

In the method of manufacturing a cold cathode fluorescent lamp of the present invention, a step (a) of preparing an electrode pin body and a step of forming a groove in which a line along the longitudinal direction of the electrode pin body is formed on the surface of the electrode pin body (b) And a step of connecting a lead wire to one end of the electrode pin body, a step of connecting a cup electrode to the other end of the electrode pin body, and welding a glass member to an area in which the groove is formed in the electrode pin body ( 공정 着) process is included.

According to the electrode pin for cold cathode discharge lamp of this invention, the groove | channel which runs along the line along the longitudinal direction of an electrode pin main body is formed in the part of the surface of an electrode pin main body which seals and is attached to the edge part of a glass bulb, The strength of a sealing part is improved. As a result, it is possible to provide a discharge lamp (cold cathode fluorescent lamp) excellent in reliability.

Moreover, according to the electrode structure of this invention, since the electrode pin for discharge lamps of this invention is employ | adopted, the said effect can be acquired as it is.

According to the cold cathode fluorescent lamp of the present invention, since the electrode pin for discharge lamp of the present invention is employed, the above effects can be obtained as it is.

In addition, according to the lighting apparatus of the present invention, the cold cathode fluorescent lamp of the present invention is employed, and thus the above effects can be obtained as it is.

In addition, according to the liquid crystal display device of the present invention, since the illumination device of the present invention is adopted as a backlight, high display quality can be ensured.

According to the manufacturing method of the electrode pin for cold cathode discharge lamps of this invention, the electrode pin for discharge lamps of this invention which can obtain the said effect, without accompanying an increase of a member, etc. can be manufactured.

In the manufacturing method of the cold cathode fluorescent lamp of the present invention, since the cold cathode fluorescent lamp can be manufactured using the discharge lamp electrode pin manufactured through the same steps as the method of manufacturing the discharge lamp electrode pin of the present invention, the member It is possible to manufacture the cold cathode fluorescent lamp of the present invention which can achieve the above effect without accompanied by the increase of.

1 is a cross-sectional view schematically showing a cold cathode fluorescent lamp 100 of Example 1 of the present invention.

2 is an enlarged view of the insertion member 17 in the cold cathode fluorescent lamp 100.

3 is a diagram schematically showing the configuration of the electrode pin 22.

4 is a cross-sectional view around the groove 30.

5 is a cross-sectional view around the groove 30.

6 is a perspective view schematically showing the configuration of the electrode pin 22.

FIG. 7: is a perspective view which shows typically the structure of the electrode pin 22. As shown in FIG.

8 is a perspective view schematically showing the configuration of the electrode pin 22.

9 is a perspective view schematically showing the configuration of the electrode pin 22.

10 is a perspective view schematically illustrating the configuration of the electrode pin 22.

11 is a drawing substitute photograph showing the configuration of an experimental sample.

It is sectional drawing for demonstrating the structure of an experiment sample.

13 is a drawing substitute photograph showing the result of the strength test.

14 is a drawing substitute photograph showing the result of the strength test.

15A to 15D are cross-sectional views illustrating a method of manufacturing the cold cathode fluorescent lamp 100 of Example 1. FIG.

16 (a) to (c) are cross-sectional views illustrating a method of manufacturing the cold cathode fluorescent lamp 100 of Example 1. FIG.

17A to 17C are cross-sectional views illustrating a method of manufacturing the cold cathode fluorescent lamp 100 of Example 1. FIG.

18 is an exploded perspective view showing the configuration of the lighting apparatus 400 of the second embodiment.

19 is a perspective view (partly cutaway sectional view) showing a configuration of a lighting apparatus 500 of the third embodiment.

20 is a perspective view (partly cutaway sectional view) showing a configuration of a liquid crystal display device 700 according to the fourth embodiment.

(Explanation of the sign)

10 Glass Bulb 10a End of Glass Bulb

12 Phosphor Layer 15 Bead Glass

17 Insertion member 20 Electrode structure

21 Electrode pin Main body 22 Electrode pin for discharge lamp

24 cup electrode 26 external lead wire

30 groove 30 longitudinal

50 Defect 100 Cold Cathode Fluorescent Lamp

400, 500 Illumination 700 Liquid Crystal Display

The inventors of the present invention have conducted various studies to improve the adhesion between the electrode pin (encapsulation rod) of the electrode portion and the end of the glass bulb in the cold cathode fluorescent lamp (that is, the strength at the portion where the bead glass is deposited). When grooves are formed on the main surface of the discharge lamp electrode pin made of tungsten or the like by laser processing, it is found that the bonding strength between the electrode pin for the discharge lamp and the glass bulb at the insertion portion can be remarkably improved. Based on the knowledge, the present invention has been reached.

[Example 1]

EMBODIMENT OF THE INVENTION Hereinafter, Embodiment 1 of this invention is described, referring drawings. In the following drawings, for the sake of brevity of description, components having substantially the same functions are denoted by the same reference numerals. In addition, this invention is not limited to a following example.

1. Cold cathode fluorescent lamp 100, electrode structure 20 and electrode pins 22 for discharge lamps

1 to 3, the cold cathode fluorescent lamp 100, the electrode structure 20 and the electrode pin 22 for the discharge lamp of the first embodiment of the present invention will be described. 1 is a cross-sectional view schematically showing the configuration of a cold cathode fluorescent lamp 100 (hereinafter referred to as "cold cathode fluorescent lamp 100") of the present embodiment, Figure 2 is a cold cathode fluorescent lamp 100 It is the figure which expands and shows the edge part 10a sealed by the bead glass 15. FIG. 3 is a figure which shows typically the structure of the electrode pin 22 (henceforth "electrode pin 22") for discharge lamps with which the cold cathode fluorescent lamp 100 is equipped.

The cold cathode fluorescent lamp 100 includes a glass bulb 10, a phosphor layer 12 formed on an inner surface of the glass bulb 10, and an electrode structure 20. The glass bulb 10 is made of a glass tube whose end 10a is sealed with bead glass 15, and mercury (Hg) is sealed in the glass bulb 10. The phosphor layer 12 is composed of, for example, phosphor powder and a binder (binder).

The electrode structure 20 includes a rod-shaped electrode pin body 21, an electrode 24 connected to one end of the electrode pin body 21, and an external lead connected to the other end of the electrode pin body 21. It is comprised by the combination of the lines 26. In the cold cathode fluorescent lamp 100, the electrode 24 is located inside the glass bulb 100, and the external lead wire 26 is located outside the glass bulb 100. The electrode pin and the external lead wire may also be referred to as electrode pins for a discharge lamp.

The electrode pins 22 are fixed to the end 10a of the glass bulb 10 via the bead glass 15. Specifically, it is provided in a state of penetrating a portion sealed by the bead glass 15, and the bead glass 15 is deposited on the main surface at this portion, thereby being fixed to the end 10a of the glass bulb 10. have. The electrode pin 22 is made of, for example, tungsten (W) or molybdenum (Mo). The electrode pin 22 of the cold cathode fluorescent lamp 100 of the present embodiment is made of, for example, tungsten (W). Pin.

The electrode 24 is composed of nickel (Ni), niobium (Nb), molybdenum (Mo), tungsten (W), and the like. The electrode 24 of the cold cathode fluorescent lamp 10 of the present embodiment has an underside as an example. It is a cylindrical electrode which is formed and is made of nickel (Ni). The external lead wire 26 is made of, for example, nickel (Ni) or Dumet, and the external lead wire 26 of the cold cathode fluorescent lamp 10 of the present embodiment is, for example, a metal made of nickel (Ni). It is good.

The electrode pin body 22 of the present embodiment has the electrode pin body 21 at the electrode pin body 21 and the portion 17 of the surface of the electrode pin body 21 that is sealed to the end portion 10a of the glass bulb 10. A groove 30 is provided to squeeze the line (imaginary line 37 parallel to the longitudinal direction 35 in FIG. 3) along the longitudinal direction 35 of 21. In other words, in the structure of this embodiment, the groove 30 is formed in the part of the surface of the electrode pin main body 21 welded by the bead glass.

More specifically, the electrode pin 22 is, for example, a region 35 along the center axis in the region where the bead glass 15 is deposited on the main surface thereof (the point 17 to be sealed) (imaginary line in FIG. 3). A groove 30 is formed extending in the direction intersecting with (the direction according to (37).) The groove 30 extends, for example, in a state of substantially turning around the central axis of the electrode pin body 21. It may be of the form.

The bead glass 15 is a glass member for sealing the end 10a of the glass bulb 10 and for fixing the electrode pin 22 to the end 10a of the glass bulb 10, for example, borosilicate It consists of glass. In the cold cathode fluorescent lamp 100 of the present embodiment, the glass bulb 10 is made of borosilicate glass as an example. Borosilicate glass is preferred because it is a glass with reduced alkali content, which can reduce the adverse effect on the phosphor layer 12.

The groove 30 formed in the surface of the electrode pin main body 21 is a spiral groove, for example. The groove 30 is formed by laser processing that irradiates a surface of the electrode pin body 21 made of tungsten (W) with a laser (for example, a YAG laser or a CO ₂ laser).

In the example shown to FIG. 1 to FIG. 3, the groove | channel 30 is formed in the spiral shape with respect to the surface of the electrode pin main body 21, In particular, 2 [rotation] or more (for example, 2 [rotation], 3 [ Rotation], 4 [rotation], 5 [rotation], 6 [rotation], or more turns) are formed on the surface of the electrode pin body 21.

In the case of the spiral groove 30 is formed so that the line along the longitudinal direction 35 of the electrode pin body 21 is seated. Specifically, for example, the electrode pin body 21 is pivoted in a state in which the circumference of the axis substantially rotates once in a direction intersecting with the longitudinal direction 35 of the electrode pin body 21.

In addition, as the groove 30, in addition to the spiral shape as shown in Figs. 1 to 3, for example, it is also possible to form an annular groove in which one end and the other end of the groove are connected. The annular groove is formed in two or more, for example.

The depth of the groove 30 is, for example, 0.5 [mu m] or more. When the grooves 30 are formed by laser processing, the depth of the grooves 30 can be set to 3 [μm] to 50 [μm], for example. Moreover, the opening width of the groove | channel 30 can be made into the width which the bead glass 15 can enter easily, for example, the width of 5 [micrometer] or more. Moreover, preferably, the opening width of the groove | channel 30 exists in the range of 5 micrometers-70 micrometers or less.

As shown in FIG. 3, the space | interval d (or pitch) of the spiral groove 30 can be 10 [micrometer]-500 [micrometer], for example, and the spiral groove 30 is The length a (length along the length direction 35) of the region to be formed can be, for example, 0.3 [mm] to 1.5 [mm]. Alternatively, the length a of the region where the spiral grooves 30 are formed is a predetermined ratio (eg, 10 [%] to 50 [%] with respect to the length L in the longitudinal direction 35 of the electrode pin body 21. I can do it. However, the shape and size (depth, spacing d, length a, spiral length, etc.) of the groove 30 may vary depending on various conditions (material and shape (diameter, length, etc.) of the electrode pin body 21, and the sealing portion 17. According to welding conditions, etc.), what is preferable is employable suitably.

2. Cross-sectional shape of the groove 30 formed in the surface of the electrode pin body 21

The cross-sectional shape of the groove 30 formed in the surface of the electrode pin main body 21 is demonstrated using FIG.

As shown in FIG. 4, the groove 30 extended so that the line 37 along the longitudinal direction 35 of the electrode pin main body 21 may be formed in the surface of the electrode pin main body 21, A part of the bead glass 15 is inserted into the recess of the groove 30, and accordingly, the sealing adhesive strength of the electrode pin 22 (or the electrode pin body 21) and the bead glass 14 (with sealing) Can improve the performance).

In other words, since both the electrode pin main body 21 (for example, tungsten (W) pin) and the bead glass 15 have different thermal expansion coefficients, the electrode pin main body 21 (eg, a pin made of tungsten (W)) differs from each other even at a level that is invisible to both eyes. A gap can occur. Due to the influence of the gap, the leakage of the sealing portion 17 (that is, the communication between the interior of the glass bulb 10 and the atmosphere) 50 is more likely to occur, but the groove 30 is formed on the surface of the electrode pin body 21. ), The bead glass 15 is inserted into the concave portion of the groove 30, so that the occurrence of the leak 50 can be prevented or reduced.

In particular, when the grooves 30 are formed by laser processing, the grooves 30 are formed by melting of a metal (for example, tungsten (W)), so that the grooves 30 are recessed as shown in FIG. 5. The convex part can be provided around the part. That is, the groove 30 is provided with a concave portion recessed more than the surface of the electrode pin body 21, and a convex portion connected to the concave portion and convex with respect to the center of the cross section rather than the surface of the electrode pin body 21. It can be made into a shape. By employing such a configuration, the effect of suppressing the occurrence of the leak 50 between the electrode pin body 21 and the bead glass 15 can be improved.

3. Electrode pin 22 and groove 30 for discharge lamp

Next, the discharge pin electrode pins 22 and the grooves 30 of the cold cathode fluorescent lamp 100 of the first embodiment will be described with reference to FIGS. 6 to 10 show perspective views schematically showing the configuration of the electrode pins 22.

As described above, when the electrode pin 22 (or the electrode pin body 21) is formed of tungsten (W) or molybdenum (Mo), the electrode pin 22 (or the electrode pin body 21). )) Is produced by stretching tungsten (W) or molybdenum (Mo) by swaging or wire drawing. In this case, as shown in FIG. 6, a defect (for example, minute parallel to the wire drawing direction) extends along the longitudinal direction 35 of the electrode pin body 21 to the surface 21a of the electrode pin body 21. Cracks) 55 may be present. If this defect 55 exists, the possibility of the leak resulting from the clearance | interval by this defect 55 becomes large.

In the cold cathode fluorescent lamp 100 of the present embodiment, as shown in FIG. Since the grooves 30 are formed along the lines 37), the defects 55 extending along the longitudinal direction 35 of the electrode pin body 21 can be blocked by the grooves 30. . As described with reference to FIGS. 4 and 5, the bead glass 15 as a part of the glass bulb 10 enters the inside of the groove 30.

Therefore, in the cold-cathode fluorescent lamp 100 of the present embodiment, the grooves 30 are formed on the surface of the electrode pin body 21 so that the leakage 50 caused by the defect 55 (for example, time after completion of the product) Can be used to solve the problem of slow leaks.

In the role of the groove 30 that blocks the defect 55 extending along the longitudinal direction 35 of the electrode pin body 21, as shown in FIG. 8, the leakage is also caused by the annular groove 30. The effect of preventing or suppressing 50) can be obtained.

In addition, as long as the defect 55 can be effectively blocked, the effect of this embodiment can be obtained even if the discontinuous groove 30 is formed as shown in FIG.

On the other hand, as shown in FIG. 10, even the groove which has a recessed part in the surface 21a of the electrode pin main body 21, the groove 32 parallel to the longitudinal direction 35 of the electrode pin main body 21 (namely, In the case of the groove 32 which does not intersect the line 37 along the longitudinal direction 35, the defect 55 extending along the longitudinal direction 35 of the electrode pin body 21 cannot be blocked. The effect of preventing the leakage 50 of the example cannot be obtained.

4. Sealing adhesion strength

Next, the improvement of the sealing adhesive strength by the structure of this Example is demonstrated, referring FIG. 11 thru | or FIG. 14. FIG.

The present inventors formed the experimental sample shown in FIG. 11 for the test of sealing strength, and measured the strength. As shown in FIG. 11, the test sample has the structure by which the bead glass 15 adhered to the area | region where the groove | channel 31 was formed in the surface of the electrode pin main body 21. As shown in FIG. Moreover, the electrode pin 22 is comprised with the electrode pin main body 21 in which the groove | channel 30 was formed, and the lead wire (external lead wire) 26 connected to the one end part of the electrode pin main body 21. As shown in FIG. The diameter of the electrode pin main body 21 and the external lead wire 26 is 0.8 [mm], respectively.

Specifically, as shown in FIG. 12, after the electrode pin main body 21 and the external lead wire 26 are connected to each other by welding, the bead glass 15 is inserted so as to be supported by the welding hump 25. (Arrow 60) Next, the bead glass 15 is fused (deposited) to the electrode pin body 21. Thus, the experimental sample shown in FIG. 11 is produced. The electrode pin body 21 used in this experiment is made of tungsten (W), and the external lead wire 26 is made of nickel (Ni).

Experimental results of the seal adhesion strength are shown in FIGS. 13 and 14. In order to separate the glass beads 15 from the electrode pin body 21 by pulling the external lead wire 26 in order to measure the sealing adhesion strength (adhesive strength) of the experimental sample shown in FIG. It was found that the external lead wire 26 made of nickel (Ni) was broken before being separated.

In the sample A shown in FIG. 13, a spiral groove 30 (depth 10 [μm] of the groove) having a rotational speed of 6 is formed. Sample B has a spiral groove 30 (groove depth 10 [µm]) of rotation number 3, and sample C has a spiral groove 30 (rotation depth 5 [µm]) of rotation number 3 ) Is formed.

As a comparative example, the adhesion strength of the test sample in which the groove was not formed on the surface of the electrode pin body was examined. As shown in FIG. 14, when the external lead wire 26 was pulled out, the bead glass 15 was removed from the electrode pin for the discharge lamp. Separated, no cutting of the outer lead wire 26 occurred. At this time, the breaking strength (breaking strength of the comparative example) was 192.7 [N] (weibull coefficient 22.9). Therefore, the breaking strength at the time of forming the groove 30 exceeds that much (actually, the breaking strength could not be measured because the adhesiveness was excellent enough to cause the external lead wire 26 to be cut).

Next, the present inventors produced the cold cathode fluorescent lamp 100 provided with the electrode pin 22, and performed the evaluation experiment which applies the thermal stress to the cold cathode fluorescent lamp 100. FIG. This experiment was carried out as follows.

First, after immersing 30 [second] in the solder which hold | maintained the external lead wire part 26 of the cold cathode fluorescent lamp 100 at 350 [degrees.], The operation | movement which cools to room temperature by natural cooling is performed 10 times. ] Was repeated. Thus, after repeatedly applying thermal stress to the sealing part 17, the lamp 100 was hold | maintained for 48 [hour] in 10 [atm] atmosphere. Then, the lighting experiment of the cold cathode fluorescent lamp 100 was done. As a result, in the cold-cathode fluorescent lamp 100 provided with the electrode pin 20 of this embodiment, it turned out that all the samples turn on and show the brightness and emission spectrum as designed. On the other hand, in the conventional cold-cathode fluorescent lamp (comparative example) in which grooves are not formed on the surface of the electrode pin main body (comparative example), samples which do not turn on at a rate of 1 [piece] to 3 [piece] out of 100 pieces are generated. did.

In addition, the inventors of the present invention conducted an evaluation experiment to apply the bending stress to the external lead wire 26 of the cold cathode fluorescent lamp 100 of the present embodiment. This experiment was carried out as follows. First, bending stress was applied to the sealing portion 17 by bending the external lead wire 26 of the cold cathode fluorescent lamp 100 at right angles to the longitudinal direction 35 of the electrode pin body. Thereafter, the lamp 100 was held in an atmosphere of 10 [atm] for 48 [hours], and the lighting experiment of the cold cathode fluorescent lamp 100 was conducted in the same manner as described above. As a result, it was found that in the cold cathode fluorescent lamp 100 having the electrode pins 22 according to the present embodiment, all the samples were turned on, and the luminance and the emission spectrum were as designed. On the other hand, in the conventional cold-cathode fluorescent lamp (comparative example) in which grooves are not formed on the surface of the electrode pin main body (comparative example), samples which do not turn on at a ratio of 1 [to 4] to 100 [to] are generated. did.

5. Method of manufacturing cold cathode fluorescent lamp 100 and electrode structure 20

Next, the manufacturing method of the cold cathode fluorescent lamp 100 and the electrode structure 20 of this embodiment is demonstrated, referring FIG. 15 and FIG. 15 and 16 are process cross-sectional views for explaining the manufacturing method of this embodiment.

First, as shown to FIG. 15 (a), the electrode pin 22 in which the groove | channel 30 was formed in the surface of the electrode pin main body 21 is produced. The electrode pin 22 in which the groove 30 is formed is provided with the electrode pin main body 21, and then the groove 30 which sits a line along the longitudinal direction 35 of the electrode pin main body on the surface of the electrode pin main body 21. It is produced by forming). The formation of the grooves 30 is carried out by laser processing (for example, using a YAG laser or a CO ₂ laser). However, the method may be chemical etching or machining as long as it can form the grooves 30 that line the line in the longitudinal direction 35 of the electrode pin body 21.

The groove 30 can be obtained, for example, by forming a recess in the surface of the electrode pin body 21 while rotating the central axis in the longitudinal direction thereof as the rotation axis. As described above, the groove 30 may be a spiral groove, an annular groove, or another shape. In addition, the electrode pin main body 21 can be obtained by extending | stretching a structural metal material (for example, tungsten (W)) by wire drawing process, etc., and cut | disconnecting to predetermined length. Since the defect 55 in the longitudinal direction 35 of the electrode pin main body 21 may arise at the time of this wire drawing process, it is preferable to implement the structure (formation of the groove | channel 30) of this embodiment.

For example, the electrode pin body 21 made of an alloy of Fe and Ni may cause a defect 55 along the longitudinal direction 35 of the electrode pin body 21, so that the technique of employing the configuration of the present embodiment It is meaningful.

Next, as shown to FIG. 15 (b), the external lead wire 26 is arrange | positioned at the one end part (for example, one side cross section) of the electrode pin main body 21 in which the groove | channel 30 was formed. Next, as shown in FIG.15 (c), the electrode pin main body 21 and the external lead wire 26 are connected by welding. Moreover, the welding hump 25 may be formed in the one end side (electrode pin main body 21 side) of the external lead wire 26 by welding. Moreover, when the groove 30 is formed in the center position in the longitudinal direction of the electrode pin main body 21, the connection direction of the electrode pin main body 21 and the external lead wire 26 is the one end part of the electrode pin main body 21. The advantage in the manufacturing process that it can do either of a side and the other end side can be acquired.

Thereafter, as shown in FIG. 15D, the bead glass 15 is inserted into the electrode pin body 21 in which the grooves 30 are formed. At this time, the bead glass 15 is inserted to cover the groove 30. In the manufacturing method of this embodiment, the welding hump 25 functions as a positioning member of the bead glass 14.

Next, as shown to Fig.16 (a), the bead glass 15 and the electrode pin body 21 are welded. This welding is performed by heating the bead glass 15. Next, as shown in FIG.16 (b), the electrode 24 is connected to the other end part (for example, other end surface) of the electrode pin main body 21 by welding, and the electrode structure 20 is obtained.

Although the adhesion between the bead glass 15 and the electrode pin body 21 may decrease due to heat during welding of the electrode 24, the groove 30 is formed on the surface of the electrode pin body 21 in the embodiment. ), The adhesion is improved, and even when heat is generated during such welding, a decrease in the adhesion between the bead glass 15 and the electrode pin body 21 can be effectively suppressed.

Next, as shown in FIG. 16C, the electrode structure 20 is inserted into the glass bulb 10 with the electrode 24 at the tip. Thereafter, the bead glass 15 and the glass bulb 10 provided in the electrode structure 20 are melted by heating, and both are brought into close contact with each other to be welded in the sealing unit 17 to thereby form the cold cathode fluorescent lamp 100 of the present embodiment. You can get it.

In addition, before and after the step of inserting the electrode structure 20 into the glass bulb 10, the process of forming the phosphor layer 12 on the inner surface of the glass bulb 10, the mercury introduction process to the glass bulb 10, and encapsulation. A gas introduction step or the like is performed.

6. Modifications related to the manufacturing method of the cold cathode fluorescent lamp 100

The cold cathode fluorescent lamp 100 of the present embodiment can also be manufactured as shown in FIG.

First, after performing the process shown in FIG.15 (c), as shown in FIG.17 (a), the cup electrode 24 is welded to the other end part (for example, other end surface) of the electrode pin main body 21. FIG. Connected by

Next, as shown in FIG.17 (b), the bead glass 15 is welded to the electrode pin main body 21. FIG. Then, as shown in FIG. 17C, the cold cathode fluorescent lamp 100 of the present embodiment can be obtained by inserting the electrode structure 20 into the glass bulb 10 and welding each other with the sealing portion 17. have.

In the assembling process of assembling the cold cathode fluorescent lamp to the backlight, a stress is applied to the outer lead wire 26 of the cold cathode fluorescent lamp, and the stress of the electrode pin body 21 in the sealing portion 17 is caused by the stress. There is a possibility that leakage occurs between the surface and the bead glass 15, but in the configuration of the present embodiment, the groove 30 is formed on the surface of the electrode pin body 21 to improve the adhesion strength in the sealing portion 17. As such, such problems can be solved.

In addition, under the situation that the lifetime of the backlight, and thus the lifetime of the liquid crystal display device, is determined by the leakage of the cold cathode fluorescent lamp, the configuration of the present embodiment can improve the lifetime of the backlight and the lifetime of the liquid crystal display device. .

In addition, in the configuration of the present embodiment, since the strength of the sealing portion 17 is improved by the formation of the grooves 30, long life and high reliability can be satisfied without using complicated structures or expensive members. As a result, The technical value is very high, including cost.

As mentioned above, although this invention was demonstrated by the preferred embodiment, such a technique is not limited and of course various changes or a change is possible.

[Example 2]

The lighting apparatus 400 of Embodiment 2 of the present invention will be described with reference to FIG. 18.

As shown in FIG. 18, the illuminating device 400 of Example 2 of this invention is a backlight unit of a direct type | mold, and has a rectangular parallelepiped-shaped housing 401 which opened one surface, and the inside of this housing 401. A plurality of stored lamps 100, a socket 402 for electrical connection to a lighting circuit (not shown) for turning on the lamp 100, and an optical sheet 403 covering an opening of the housing 401. ).

In addition, the cold cathode fluorescent lamp 100 of Example 1 is employ | adopted as the lamp 100 of the illuminating device 400 of this embodiment.

The housing 401 is made of polyethylene terephthalate (PET) resin, for example, and the reflection surface 404 is formed on the inner surface by vapor deposition of a metal such as silver (Ag).

As the material of the housing 401, a material other than a resin material, for example, a metal material such as aluminum (Al) or a cold rolled material (for example, SPCC) may be employed. . In addition to the metal-deposited film, the reflective surface 404 of the inner surface is further provided with a reflective sheet having a higher reflectivity by adding calcium carbonate, titanium dioxide, or the like to a polyethylene terephthalate (PET) resin, to the housing 401. It can also be used.

The socket 402, the insulator 405, and the cover 406 are disposed inside the housing 401. The sockets 402 are provided at predetermined intervals in the width direction (vertical direction) of the housing 401 in correspondence with the arrangement of the lamp 100. The socket 402 is formed by processing a plate made of stainless steel or phosphor bronze, for example, and has an insertion portion 402a into which the external lead wire 104b is inserted. And the lead wire 103 is inserted by elastically deformed to widen the insertion portion 402a. As a result, the external lead wire 103a inserted into the insertion part 402a is pressed by the restoring force of the insertion part 402a, and is hard to fall. This makes it possible to easily insert the external lead wire 103a into the insertion portion 402a, and to prevent it from falling off once inserted.

The socket 402 is covered with an insulator 405 so that the sockets 402 adjacent to each other are not shorted. The insulator 405 is formed using polyethylene terephthalate (PET) resin, for example.

In addition, the insulator 405 is not limited to the said structure.

Since the socket 402 is arranged near the electrode 102 which becomes relatively high temperature during the operation of the lamp 100, the insulator 405 is preferably made of a material having heat resistance. For example, polycarbonate (PC) resin, silicone rubber, or the like may be used as the material of the heat resistant insulator 405.

In the housing 401, a lamp holder 407 may be provided at a desired location. The lamp holder 407 fixing the position of the lamp 100 inside the housing 401 has a shape that conforms to the outer surface shape of the lamp 100 using, for example, polycarbonate (PC) resin.

Here, the above-mentioned "point as needed" is a case where the lamp 100 has a length exceeding a total length of 600 [mm], such as near the center part in the longitudinal direction of the lamp 100, It is a location necessary for eliminating the warping of the lamp 100.

The cover 406 partitions the space inside the socket 402 and the housing 401, and is formed using, for example, polycarbonate (PC) resin, and at the same time insulates the periphery of the socket 402, By at least making the surface of the housing 401 side highly reflective, the fall of the brightness | luminance of the edge part of the lamp 100 can be reduced.

The opening of the housing 401 is covered with a light-transmitting optical sheet 403, and is sealed to prevent foreign substances such as dust and dust from entering the inside. The optical sheet 403 is configured by stacking the diffusion plate 408, the diffusion sheet 409, and the lens sheet 410.

The diffusion plate 408 is, for example, a plate-shaped body made of polymethyl methacrylate (PMMA) resin, and is disposed to cover the opening of the housing 401. The diffusion sheet 409 is comprised using polyester resin, for example. The lens sheet 410 is composed of, for example, adhesion of an acrylic resin and a polyester resin. These optical sheets 403 are arranged so as to overlap each other in the diffusion plate 408 one by one.

As described above, the lighting apparatus 400 according to the second embodiment of the present invention is excellent in reliability.

Example 3

The lighting apparatus 500 of Embodiment 3 of the present invention will be described with reference to FIG. 19. 19 is a perspective view (partly cut away) of the lighting apparatus 500 of Embodiment 3 of the present invention.

As shown in FIG. 19, the lighting apparatus 500 of Embodiment 3 of the present invention is an edge light type backlight unit, which includes a reflector plate 501, a lamp 100, a socket (not shown), a light guide plate 502, and a diffuser. It is comprised including the sheet 503, the prism sheet 504, etc.

The reflective plate 501 is disposed to surround the light guide plate 502 except for the liquid crystal panel side (arrow Q), and has a curved lamp side portion (501a) that covers the bottom surface and a curved shape that covers the circumference of the lamp 100. 501c, and the light irradiated from the lamp 100 is reflected from the light guide plate 502 to the liquid crystal panel (not shown) side (arrow Q). In addition, the reflecting plate 501 is made of, for example, one obtained by depositing silver (Ag) on a film-like polyethylene terephthalate (PET), or laminated with a metal foil such as aluminum.

The socket (not shown) has a configuration substantially the same as that of the socket 402 used in the lighting apparatus 400 of the second embodiment.

The light guide plate 502 guides the light reflected by the reflecting plate 501 to the liquid crystal panel side, and is made of, for example, a transparent plastic, and is laminated on the reflecting plate 501a provided on the underside of the lighting apparatus 500. Moreover, polycarbonate (PC) resin, cycloolefin resin (COP), etc. can be used as a constituent material.

The diffusion sheet 503 is for expanding the field of view, and is made of, for example, a film having a diffusion transmission function made of polyethylene terephthalate resin or polyester resin and laminated on the light guide plate 502.

The prism sheet 504 is for improving luminance, and is made of, for example, a sheet to which an acrylic resin and a polyester resin are attached, and are stacked on the diffusion sheet 503. In addition, the diffusion sheet 503 may be further stacked on the prism sheet 504.

In the lighting apparatus 500 according to the third embodiment of the present invention, the glass bulb 10 is removed except for a portion in the circumferential direction of the lamp 100 (the light guide plate 502 when inserted into the lighting apparatus 500). An aperture type lamp having a reflective sheet (not shown) provided on the outer surface may be used.

As described above, the lighting apparatus 500 of Embodiment 3 of the present invention is excellent in reliability.

Example 4

A configuration of the liquid crystal display device 700 of Embodiment 4 of the present invention will be described with reference to FIG.

As shown in Fig. 20, the liquid crystal display device 700 according to the fourth embodiment of the present invention is, for example, a 32-inch liquid crystal television, and includes a liquid crystal display unit 701 including a liquid crystal panel and the like. The lighting device 400 of 2 and the lighting circuit 702 are comprised.

The liquid crystal display unit 701 is a known one and includes a liquid crystal panel (color filter substrate, liquid crystal, TFT substrate, etc .: not shown), and forms an image based on an image signal input from the outside.

The lighting circuit 702 is a circuit for driving the lamp 100 inside the lighting device 400 by lighting. The lamp 100 operates at a lighting frequency of 40 [kHz] to 100 [kHz] and a lamp current of 3.0 [kHz] to 25 [kHz].

In addition, in the fourth embodiment of the present invention, the illumination device 400 is applied as an example of the illumination device of the liquid crystal display device 700. In addition, the illumination device 500 may be applied.

As described above, in the liquid crystal display device 700 of Embodiment 4 of the present invention, high display quality can be ensured.

The present invention is useful for realizing a discharge lamp (cold cathode fluorescent lamp), an illumination device, and a liquid crystal display device having excellent reliability with a simple configuration.

Claims (26)

Electrode pin for cold cathode discharge lamp is sealed to the end of the glass bulb, With the electrode pin body, An electrode pin for a cold cathode discharge lamp, characterized in that a groove is formed to seal a line along the longitudinal direction of the electrode pin body at a portion of the surface of the electrode pin body sealed at the end of the glass bulb. The method of claim 1, And said groove is formed in a spiral shape on the surface of said electrode pin body. The method of claim 2, And said spiral groove is formed at least 2 [rotation] on the surface of said electrode pin body. The method of claim 1, The groove is the electrode pin for cold cathode discharge lamp, characterized in that formed on the surface of the electrode pin body is connected to one end and the other end in an annular shape. The method of claim 4, wherein And the annular groove is formed at two or more on the surface of the electrode pin main body. The method of claim 1, An electrode pin for a cold cathode discharge lamp, characterized in that the depth of the groove is 0.5 [㎛] or more. The method of claim 1, The groove is, A concave portion recessed more concave than the surface of the electrode pin body, And a convex portion connected to the concave portion, which is convex than the surface of the electrode pin body, wherein the electrode pin for a cold cathode discharge lamp is provided. The method of claim 1, The electrode pin body is an electrode pin for a cold cathode discharge lamp, characterized in that is produced by stretching by a swaging (swaging) process or a wire drawing (wire drawing) process. The method of claim 1, The electrode pin body is an electrode pin for cold cathode discharge lamp, characterized in that consisting of tungsten or molybdenum. The method of claim 1, The electrode pin body is an electrode pin for cold cathode discharge lamp, characterized in that consisting of an alloy of iron and nickel. The method of claim 1, The groove is formed by laser processing, the electrode pin for cold cathode discharge lamp, characterized in that. The method of claim 1, A lead wire is connected to one end of the electrode pin body, wherein the electrode pin for a cold cathode discharge lamp. 13. The method of claim 12, The lead wire is an electrode pin for cold cathode discharge lamp, characterized in that consisting of nickel. Has an electrode pin for cold cathode discharge lamp is sealed to the end of the glass bulb, The electrode pin for cold cathode discharge lamp, With the electrode pin body, It is provided with the groove | channel which sits along the line along the longitudinal direction of the said electrode pin main body in the part sealedly attached to the edge part of the said glass bulb among the surface of the said electrode pin main body, A lead wire is connected to one end of the electrode pin body, A cup electrode is connected to the other end of the electrode pin body. The method of claim 14, The electrode structure characterized in that the glass bead is sealed to the surface of the electrode pin body. Glass Bulb, A phosphor layer formed on an inner surface of the glass bulb, Has an electrode pin for cold cathode discharge lamp is sealed to the end of the glass bulb, A cold cathode fluorescent lamp comprising the electrode pin for cold cathode discharge lamp according to any one of claims 1 to 11 as the electrode pin for cold cathode discharge lamp. The method of claim 16, The glass bulb is cold cathode fluorescent lamp, characterized in that consisting of borosilicate glass. In the manufacturing method of the electrode pin for cold cathode discharge lamp, (A) preparing an electrode pin main body, And (b) forming a groove on the surface of the electrode pin body in a line along the longitudinal direction of the electrode pin body. The method of claim 18, The said process (b) is a manufacturing method of the electrode pin for cold cathode discharge lamps characterized by performing by laser processing. The method of claim 18, The method of manufacturing an electrode pin for a cold cathode discharge lamp, characterized in that for forming the groove in a spiral shape while rotating the electrode pin body in the step (b). The method of claim 18, The method of manufacturing an electrode pin for a cold cathode discharge lamp, characterized in that for forming the groove in an annular shape connected to one end and the other end while rotating the electrode pin body in the step (b). The method of claim 18, The step (a), A method of manufacturing an electrode pin for a cold cathode discharge lamp, comprising: a sub-step of stretching a metal material constituting the electrode pin body by swaging or wire drawing. The method of claim 22, The material constituting the electrode pin body is a manufacturing method of the electrode pin for cold cathode discharge lamp, characterized in that the tungsten or molybdenum. (A) preparing an electrode pin main body, (B) forming a groove on the surface of the electrode pin main body to sit a line along the longitudinal direction of the electrode pin main body; Connecting a lead wire to one end of the electrode pin body; Connecting a cup electrode to the other end of the electrode pin body; And welding a glass member to a region where the groove is formed in the electrode pin body. The cold cathode fluorescent lamp of Claim 16 is provided, The illuminating device characterized by the above-mentioned. The illuminating device of Claim 25 is provided, The liquid crystal display device characterized by the above-mentioned.

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