JP2010192133A - Discharge lamp, backlight unit, and liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp preventing crack of the sealed porion of a glass bulb and the peripheral surface of the glass bulb where a feeding terminal is mounted, even when force such as vibration and impact is applied to the feeding terminal of the discharge lamp. <P>SOLUTION: Electrodes are provided inside of both end portions 10b of the glass bulb 10, both end portions 10b are sealed and formed by thermal processing to be larger than the diameter of the center portion of the glass bulb 10, and feeding terminals 30 connected to the lead wire 22 of the electrodes are provided on the peripheral surface of both end portions 10b of the glass bulb. The feeding terminal 30 abuts on the peripheral surface of the glass bulb 10 except for both end portions 10b which are larger than the outer diameter of the center portion of the glass bulb 10, and has a conductive cylindrical body 31 provided to surround the glass bulb. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a discharge lamp, a backlight unit, and a liquid crystal display device, and more particularly, to a discharge lamp having a power supply terminal arranged on an outer peripheral surface of an end portion of a glass bulb.

  Conventionally, there are discharge lamps 3600 and 3700 in which cap-shaped power supply terminals 3602 and 3702 are provided at both ends of glass bulbs 3601 and 3701 as shown in FIGS.

  A discharge lamp 3600 shown in FIG. 23 includes a cylindrical body 3602a provided on the outer peripheral surface of the end portion of the glass bulb 3601, and a strip-shaped lead-out portion 3602c extending from one end 3602b of the cylindrical body 3602a to the axially outer side of the cylindrical body 3602a. And a power supply terminal 3602 including a connection portion 3602d formed by bending from the tip of the lead-out portion 3602c. A lead wire 3604 extending from the end of the glass bulb 3601 is disposed in the through hole of the connection portion 3602d, and the through hole and the lead wire 3604 are welded with solder 3605. The elastic holding piece 3606 formed on the cylindrical body 3602a and projecting inward in the radial direction is brought into contact with the outer peripheral surface of the glass bulb 3601 and is interposed between the inner surface of the cylindrical body 3602a and the outer peripheral surface of the glass bulb 3601. It is held at the end 3607 of the glass bulb 3601 with a gap (Patent Document 1).

  Further, a discharge lamp 3700 shown in FIG. 24 has a cylindrical body 3702a provided on the outer peripheral surface of the end portion of the glass bulb 3701, and a strip-like lead extending from the one end 3702b of the cylindrical body 3702a to the outer side in the axial direction of the cylindrical body 3702a. A portion 3702c and a power supply terminal 3702 including a connection portion 3702d formed by bending from the tip of the lead-out portion 3702c are provided. A lead wire 3704 extending from the end of the glass bulb 3701 is disposed in the through hole of the connection portion 3702d, and the through hole and the lead wire 3704 are welded with solder 3705. The bead 3706 formed on the cylindrical body 3702a and projecting radially inward is brought into contact with the outer peripheral surface of the glass bulb 3701, and a gap is provided between the inner surface of the cylindrical body 3602a and the outer peripheral surface of the glass bulb 3601. In this state, the glass bulb 3701 is held by the end 3707 (Patent Document 2).

Since the power supply terminals 3602 and 3702 having the configurations shown in FIGS. 23 and 24 are electrically connected to the lead wires 3604 and 3704 of the electrodes 3603 and 3703, the ends of the discharge lamps 3600 and 3700 are connected to a backlight unit or the like. When fitted in a lamp socket (not shown) of the lighting device, the discharge lamps 3600 and 3700 can be fixed to the lighting device, and the discharge lamps 3600 and 3700 and the lighting circuit of the lighting device can be electrically connected. it can. Therefore, when the discharge lamps 3600 and 3700 are attached to the lighting device, soldering of the lead wires 3604 and 3704 is unnecessary, and attachment is easier than a discharge lamp in which the power supply terminals 3602 and 3702 are not provided.
International Publication No. 2008/001562 Pamphlet JP 2007-234551 A

  By the way, in the discharge lamp 3600 having the power supply terminal 602 as shown in FIG. 23, when the power supply terminal 3602 is fitted into the lamp socket, a force is applied to the elastic holding piece 3606, the lamp incorporation process or the lamp unit transport process. In addition, when a force such as vibration or impact is applied to the power supply terminal 3602 of the discharge lamp 3600, the gap between the inner surface of the cylindrical body 3602a and the outer peripheral surface of the glass bulb 3601 changes. That is, the lead wire 3604 from which the force when the power supply terminal 3602 is fitted into the lamp socket or the force such as vibration or impact on the power supply terminal 3602 extends from the end portion of the glass bulb 601 from the connection portion 3602d of the strip-shaped lead-out portion 3602c. May cause cracking of the sealing portion of the glass bulb.

  On the other hand, in the discharge lamp 3700 provided with the power supply terminal 702 as shown in FIG. 24, the power supply terminal 3702 is provided with the bead 3706 formed on the cylindrical body 3702a in contact with the outer peripheral surface of the glass bulb 3701. When an impact force is applied to the power supply terminal 3702 of the discharge lamp 3700 during the lamp assembly process or the lamp unit transport process, a concentrated load is applied from the bead 3706 to the surface of the glass bulb 3701, and cracks occur in the thin glass bulb. Sometimes.

  In view of the above problems, the present invention is a case where, when the power supply terminal is fitted into the socket, a force such as vibration or impact is applied to the power supply terminal of the discharge lamp during the lamp incorporation process or the lamp unit transport process. Another object of the present invention is to provide a discharge lamp, a backlight unit, and a liquid crystal display device that can prevent cracks from occurring on the outer peripheral surface of the glass bulb to which the sealing portion of the glass bulb and the power supply terminal are attached.

  In order to solve the above-mentioned problem, in the discharge lamp according to claim 1 of the present invention, electrodes are provided inside the both ends of the glass bulb, and both ends are formed from the outer diameter of the central portion of the glass bulb by thermal processing. A discharge lamp that is largely sealed and has a power feeding terminal connected to the lead wires of the electrodes on the outer peripheral surfaces of both ends of the glass bulb, wherein the power feeding terminal has an outer diameter at the center of the glass bulb It has a conductive cylindrical body provided so as to contact and surround the outer peripheral surface of the glass bulb excluding the larger end portions.

  The discharge lamp according to claim 2 of the present invention is characterized in that the electrode is a hollow electrode, and the inner surface of the cylindrical body is in close contact with the outer peripheral surface of the glass bulb facing the hollow electrode.

  The discharge lamp according to claim 3 of the present invention is characterized in that the cylindrical body has a slit portion in the axial direction thereof and has a substantially C-shaped cross section.

  In the discharge lamp according to claim 4 of the present invention, the cylindrical body has a pair of engagements engaged with each other across a part of the pair of end edges facing each other across the slit part. A joint portion is provided.

  In the discharge lamp according to claim 5 of the present invention, the pair of engaging portions of the cylindrical body are formed with a concave portion on one end edge of the slit portion and a convex portion on the other end edge. It is characterized by being.

The discharge lamp according to claim 6 of the present invention is characterized in that a plurality of convex portions are formed on the outer peripheral surface of the cylindrical body.
In the discharge lamp according to claim 7 of the present invention, the plurality of convex portions are formed on the outer peripheral surface of the cylindrical body in a circumferential direction, an axial direction, or a spiral direction with respect to the axial center. It is characterized by being.

  In the discharge lamp according to claim 8 of the present invention, the cylindrical body is characterized in that at least the inner surface of the end opposite to the axial lead wire side is chamfered or formed in a trumpet shape.

  In the discharge lamp according to claim 9 of the present invention, the cylindrical body includes a first cylindrical portion and a second cylindrical portion that extends in the axial direction from at least one end portion of the first cylindrical portion. And the second cylinder part has an outer diameter larger than that of the first cylinder part.

  In the discharge lamp according to claim 10 of the present invention, the cylindrical body has a plurality of elastic tongue pieces provided along the circumferential direction, and the plurality of elastic tongue pieces sandwich the outer peripheral surface of the glass bulb. It is characterized by.

  In the discharge lamp according to an eleventh aspect of the present invention, the cylindrical body has a holding member that protrudes radially inward on the inner surface thereof, presses the outer peripheral surface of the glass bulb, and holds the glass bulb. It is characterized by that.

  In the discharge lamp according to claim 12 of the present invention, the clamping member is formed by bending a part of the cylindrical body and pressing a part of the bending against the outer peripheral surface of the glass bulb. To do.

  In the discharge lamp according to a thirteenth aspect of the present invention, the holding member extends from one end side to the other end side of the cylindrical body and is bent from the one end side to the glass bulb side. It is characterized by being a belt-like body.

  In a discharge lamp according to a fourteenth aspect of the present invention, the cylindrical body is formed of a metal material wound in a spiral shape.

  The discharge lamp according to claim 15 of the present invention is characterized in that the cylindrical body is formed of a linear or belt-like elastic material in close contact with the cylindrical body in the axial direction.

  In the discharge lamp according to claim 16 of the present invention, the power supply terminal includes a connection portion that extends from the tubular body toward the lead body side in the axial direction of the tubular body and is connected to a part of the lead wire. It is characterized by being.

  In the discharge lamp according to a seventeenth aspect of the present invention, the feeding terminal is formed by extrapolating the cylindrical body to the outer periphery of the end portion of the glass bulb, and one end of the cylindrical body in the axial direction of the cylindrical body. And a strip-shaped lead-out portion extending outward from the lead-out portion and a connection portion provided at a tip portion of the lead-out portion and connected to a part of the lead wire.

  The discharge lamp according to claim 18 of the present invention is characterized in that the connection portion is formed with a U-shaped portion so as to approach a part of the outer peripheral surface of the lead wire.

  The discharge lamp according to claim 19 of the present invention is characterized in that the connecting portion is formed with a cylindrical portion so as to be close to and surround a part of the outer peripheral surface of the lead wire.

  In the discharge lamp according to claim 20 of the present invention, the connection part has a connection surface in which a through hole or a cutout part is formed, and the lead-out is performed so that the lead wire is inserted into the through hole or the cutout part. It is characterized in that it is formed by bending a part ahead of the tip of the part.

  In a discharge lamp according to a twenty-first aspect of the present invention, the connecting portion is connected to the lead wire by caulking.

  In a discharge lamp according to a twenty-second aspect of the present invention, the connecting portion is formed by bending from the leading end of the lead-out portion so as to sandwich a part of the outer peripheral surface of the lead wire. It is characterized by that.

  In a discharge lamp according to a twenty-third aspect of the present invention, the connecting portion has a pair of sandwiching pieces for sandwiching an outer peripheral surface of the lead wire, and each pressing force of the pair of sandwiching pieces is applied to the lead wire. It is at least 100 g or more, and is connected by sandwiching the lead wire.

In a discharge lamp according to a twenty-fourth aspect of the present invention, the connecting portion is formed by bending a portion ahead of the extending tip of the lead-out portion so as to be in surface contact with one end surface of the lead wire. It is characterized by being.
In the discharge lamp according to claim 25 of the present invention, the connecting portion is formed by bending a portion ahead of the leading end of the lead-out portion so as to contact a part of the outer peripheral surface of the lead wire. It is characterized by that.
In a discharge lamp according to a twenty-sixth aspect of the present invention, the connecting portion is connected to a part of the outer surface of the lead wire by welding or a soft metal.
In the discharge lamp according to a twenty-seventh aspect of the present invention, the lead wire has a pooled portion having a larger outer diameter than a portion sealed to the glass bulb at a portion joined to the power feeding terminal, At least a part of the puddle portion is formed of nickel material, iron material, or nickel plating.
In a discharge lamp according to a twenty-eighth aspect of the present invention, the lead wire is made of a nickel material, an iron material, or nickel plating, and is made of a material different from the external lead wire to which the power feeding terminal is connected. The present invention is characterized in that an internal lead wire to which a hollow electrode is joined is joined, and the joint portion has a pool portion having an outer diameter larger than that of the lead wire. In the discharge lamp according to Item 29, the pooled portion is embedded at the end portion of the glass bulb, with the bottom surface in close contact, or with the bottom surface in close contact with the gap in the radial direction of the lead wire. It is.
In a discharge lamp according to a thirty-third aspect of the present invention, the pool portion is provided with a gap from an end portion of the glass bulb.
In the discharge lamp according to a thirty-first aspect of the present invention, the gap is 0.1 mm to 0.5 mm.
In a discharge lamp according to a thirty-second aspect of the present invention, the pooled portion has a circular cross section perpendicular to the axis of the lead wire, and the maximum diameter is larger than the maximum outer diameter of the lead wire. The size is smaller than the maximum outer diameter.
In the discharge lamp according to a thirty-third aspect of the present invention, the lead wire is characterized in that the external lead has a smaller heat transfer coefficient than the internal lead.
In a discharge lamp according to a thirty-fourth aspect of the present invention, the lead wire is characterized in that the external lead wire has a diameter smaller than that of the internal lead wire.
In a discharge lamp according to a thirty-fifth aspect of the present invention, a surface roughness of at least a portion of the lead wire sealed to the glass bulb is 0.2 Ra to 0.8 Ra.
In a discharge lamp according to a thirty-sixth aspect of the present invention, one end of the lead wire is welded and fixed to the hollow electrode, the surface of the one end is 0.2 Ra to 0.8 Ra, and the chamfer dimension is a radial direction. The length is 0.08 mm to 0.15 mm and the axial length is 0.1 mm to 0.25 mm.
In a discharge lamp according to a thirty-seventh aspect of the present invention, a part of the connection part is abutted against a pooled part of the lead wire.
In a discharge lamp according to a thirty-eighth aspect of the present invention, the connection portion has a heat transfer coefficient larger than that of the lead wire.
In a discharge lamp according to a thirty-ninth aspect of the present invention, the connecting portion has a heat transfer coefficient of 75 W / (m · K) to 435 W / (m · K) and a conductivity of 9 × 10 ⁶ S / m. It is -65 * 10 < ⁶ > S / m.
In a discharge lamp according to a fortieth aspect of the present invention, the glass bulb is formed of a glass material having a sodium oxide content of 3 wt% to 20 wt%.
In a discharge lamp according to a 41st aspect of the present invention, the glass bulb is formed of a glass material having a sodium oxide content of 5 wt% to 20 wt%.
A backlight unit according to claim 42 of the present invention is characterized in that the discharge lamp according to any one of claims 1 to 41 is provided as a light source.
A liquid crystal display device according to claim 43 of the present invention comprises a liquid crystal display panel and the backlight unit according to claim 42, wherein the backlight unit is the discharge according to any one of claims 1 to 40. It has an envelope for storing a plurality of lamps, and the envelope is arranged on the back surface of the liquid crystal display panel.

  According to the discharge lamp of the first aspect of the present invention, the power supply terminal is a conductive electrode provided so as to contact and surround the outer peripheral surface of the glass bulb excluding both ends larger than the outer diameter of the central portion of the glass bulb. Because it has a cylindrical body, when a power supply terminal is fitted into the socket, a force such as vibration or impact is applied to the power supply terminal of the discharge lamp during the lamp assembly process or the lamp unit transport process. Even if it exists, it can prevent that the crack arises in the outer peripheral surface of the glass bulb to which the sealing part and power feeding terminal of the glass bulb were attached.

  According to the discharge lamp according to claim 2 of the present invention, the electrode is a hollow electrode, and the inner surface of the cylindrical body is in close contact with the outer peripheral surface of the glass bulb facing the hollow electrode, so that it is heated by the hollow electrode. Therefore, mercury on the inner surface of the glass bulb facing the hollow electrode is difficult to accumulate, and the phenomenon that the mercury vapor in the discharge path is insufficient and the lamp luminance is lowered or the rise of the lamp luminance is delayed is unlikely to occur.

According to the discharge lamp according to claim 3 of the present invention, the cylindrical body has a slit portion in the axial direction and has a substantially C-shaped cross section. It can be absorbed by the elastic force of the substantially C-shaped part, and the power supply terminal can be held on the outer peripheral surface of the glass bulb.
According to the discharge lamp according to claim 4 of the present invention, the cylindrical body has a pair of engagements that engage with each other across the slit portion on a part of each of the pair of end edges facing each other across the slit portion. By providing the part, the shape of the cylindrical body can be stabilized.
According to the discharge lamp according to claim 5 of the present invention, the pair of engaging portions of the cylindrical body are formed such that a concave portion is formed on one end edge of the slit portion and a convex portion is formed on the other end edge. Thus, it is possible to absorb the dimensional tolerance of the outer shape of the glass bulb while stabilizing the cylindrical body.
According to the discharge lamp of the sixth aspect of the present invention, when a plurality of convex portions are formed on the outer peripheral surface of the cylindrical body, when the power supply terminal is attached to and detached from the lamp socket, the contact with the power supply terminal is achieved. Since the area is small, the power supply terminal can be easily attached and detached.
According to the discharge lamp of the seventh aspect of the present invention, the plurality of convex portions are formed on the outer peripheral surface of the cylindrical body in the circumferential direction, the axial direction, or the spiral direction with respect to the axial center. Therefore, by forming a plurality of convex portions on the outer peripheral surface of the cylindrical body, the outer diameter of the cylindrical body can be increased, and in the manufacturing process, the convex portion on the outer peripheral surface of the cylindrical body is impacted. Is absorbed by the entire inner peripheral surface of the cylindrical body through the convex portion, so that the glass bulb can be prevented from being damaged.
According to the discharge lamp according to claim 8 of the present invention, the cylindrical body has at least the inner surface of the end opposite to the axial lead wire side formed in a chamfered shape or a trumpet shape. The glass bulb surface is prevented from being damaged when the is inserted into the glass bulb, and the power supply terminal can be easily attached to the glass bulb.
According to the discharge lamp of the ninth aspect of the present invention, the cylindrical body includes the first cylindrical portion and the second cylindrical portion extending in the axial direction from at least one end portion of the first cylindrical portion. The second tube portion has an outer diameter larger than that of the first tube portion, so that it is easy to position in the tube axis direction of the lamp using a step between the first tube portion and the second tube portion.
According to the discharge lamp of the tenth aspect of the present invention, the cylindrical body has a plurality of elastic tongue pieces provided along the circumferential direction, and the outer peripheral surface of the glass bulb is sandwiched between the plurality of elastic tongue pieces. As a result, an equally distributed load is applied to the entire outer peripheral surface of the cylindrical body, so that the glass bulb can be prevented from cracking. In addition, since the adhesion between the inner surface of the cylindrical body and the outer peripheral surface of the glass bulb is improved, the feed terminal is less likely to move in the tube axis direction with respect to the glass bulb after the feed terminal is attached to the glass bulb. it can.
According to the discharge lamp of the eleventh aspect of the present invention, the cylindrical body has a holding member that protrudes radially inward on the inner surface thereof, presses the outer peripheral surface of the glass bulb, and holds the glass bulb. Therefore, the clamping force for clamping the glass bulb can be adjusted.
According to the discharge lamp according to claim 12 of the present invention, the sandwiching member is formed by bending a part of the cylindrical body and pressing the bent part against the outer peripheral surface of the glass bulb. The clamping force for clamping can be adjusted.
According to the discharge lamp of the thirteenth aspect of the present invention, the holding member extends from one end side of the cylindrical body to the other end side and is bent from the one end side to the glass bulb side. By being a body, the cylindrical body can be easily positioned in the tube axis direction.
According to the discharge lamp of the fourteenth aspect of the present invention, the cylindrical body is made of a metal material wound in a spiral shape, so that an evenly distributed load is applied to the entire outer peripheral surface of the cylindrical body. In addition, the glass bulb can be prevented from cracking. In addition, since the adhesion between the inner surface of the cylindrical body and the outer peripheral surface of the glass bulb is improved, the feed terminal is less likely to move in the tube axis direction with respect to the glass bulb after the feed terminal is attached to the glass bulb. it can. Furthermore, it is easy to attach the cylindrical body to the end portion of the glass bulb, and it is possible to cope with the tube outer diameters of different glass bulbs.
According to the discharge lamp of the fifteenth aspect of the present invention, the cylindrical body is formed of a linear or belt-like elastic material in close contact with the cylindrical body in the axial direction. A material can be formed, and material loss does not occur as compared with the case of pressing a metal plate, and material loss can be reduced. In addition, since the linear or belt-like elastic material is in close contact with the cylindrical body in the axial direction, the cylindrical body is not easily deformed.
According to the discharge lamp of the sixteenth aspect of the present invention, the power supply terminal includes a connecting portion that extends from the tubular body toward the lead body side in the axial direction of the tubular body and is connected to a part of the lead wire. Therefore, the same material can be integrally formed, and the number of parts is reduced to one, and the shape accuracy of the power feeding terminal is improved. Therefore, it can be easily attached to the end of the glass bulb.
According to the discharge lamp of the seventeenth aspect of the present invention, the power supply terminal is such that the cylindrical body is extrapolated to the outer periphery of the end portion of the glass bulb, and the outer side from one end in the axial direction of the cylindrical body. A strip-shaped lead-out portion extending to the lead-out portion and a connection portion provided at the leading end of the lead-out portion and connected to a part of the lead wire. Thus, it is possible to further prevent leakage due to breakage of the glass bulb to which the lead wire is sealed.
According to the discharge lamp of the eighteenth aspect of the present invention, the connection portion is formed with a U-shaped portion so as to approach a part of the outer peripheral surface of the lead wire. The terminal is positioned in the axial direction, that is, the bending force applied to the lead wire can be suppressed, and the U-shaped portion and the lead wire can be electrically and stably connected.
According to the discharge lamp of the nineteenth aspect of the present invention, the connecting portion is formed of a cylindrical portion so as to be close to and enclose a part of the outer peripheral surface of the lead wire. On the other hand, the cylindrical portion and the lead wire can be electrically and stably connected while suppressing the bending force applied to the lead wire in the axially positioned state of the power supply terminal.
According to the discharge lamp of the twentieth aspect of the present invention, the connecting portion has a connecting surface in which a through hole or a notch is formed, and the lead portion is inserted into the through hole or the notch. By bending the part beyond the tip, the power supply terminal is positioned in the axial direction, that is, the bending force applied to the lead wire is suppressed, and the connection surface and the lead wire are connected. A stable connection is possible.
According to the discharge lamp of the twenty-first aspect of the present invention, since the connecting portion is connected to the lead wire by caulking, it can be connected without applying heat to the lead wire. It is possible to prevent cracking due to thermal shock.
According to the discharge lamp of the twenty-second aspect of the present invention, the connecting portion is formed by being bent from the leading end of the lead-out portion so as to sandwich a part of the outer peripheral surface of the lead wire. The lead wire is formed by bending from the leading end of the lead-out portion so that the outer peripheral surface of the lead wire is sandwiched at 2 or more from the direction perpendicular to the axis so that no bending force is applied to the wire. It can be easily connected to the lead wire while suppressing the bending force. As a result, it is possible to prevent leakage due to breakage of the portion where the lead wire of the glass bulb is sealed.
According to the discharge lamp of the twenty-third aspect of the present invention, the connecting portion has a pair of sandwiching pieces that sandwich the outer peripheral surface of the lead wire, and each pressing force of the pair of sandwiching pieces is at least 100 g against the lead wire. As described above, since the lead wire is sandwiched and connected, the bending force applied to the lead wire can be suppressed, and the lead wire can be electrically and stably connected.
In the discharge lamp according to claim 24 of the present invention, the connecting portion is formed by bending a portion beyond the extending tip of the lead-out portion so as to come into surface contact with one end surface of the lead wire. The bending force applied to the lead wire can be suppressed, and the power supply terminal can be positioned in the axial direction with respect to the glass bulb.

In the discharge lamp according to claim 25 of the present invention, the connecting portion is formed by bending a portion ahead of the leading end of the lead-out portion so as to contact a part of the outer peripheral surface of the lead wire. Thus, the connection portion and the lead wire can be fixed by connection using a soft metal, laser welding, or the like. Particularly, resistance welding in which two members are sandwiched between electrodes can be easily performed and is effective. Further, the power supply terminal can be positioned in the axial direction with respect to the glass bulb.
In the discharge lamp according to claim 26 of the present invention, the connecting portion is connected to a part of the outer surface of the lead wire by welding or soft metal, so that the connecting portion is further electrically stabilized to the lead wire. Can be connected.
In the discharge lamp according to claim 27 of the present invention, the lead wire has a thickened portion having a larger outer diameter than the portion sealed to the glass bulb at the portion joined to the power supply terminal, Since at least a part is formed of nickel material, iron material, or nickel plating, for example, when connecting with solder, the power supply terminal can be reliably connected to the lead wire.
In the discharge lamp according to the twenty-eighth aspect of the present invention, the lead wire is made of nickel material, iron material, or nickel plating, and the lead wire is made of a material different from the external lead wire to which the power feeding terminal is connected. Is connected to the internal lead wire to which the power supply terminal is connected, and has a pooled portion whose outer diameter is larger than that of the lead wire at the joint. Since the lead wire can be easily soldered and welded, and the connection area can be increased at the pooled portion, the connection with the power supply terminal can be ensured.
In the discharge lamp according to claim 29 of the present invention, the puddle portion is embedded at the end portion of the glass bulb with its bottom surface closely or with its bottom surface closely and with a gap in the radial direction of the lead wire. By being a thing, the leak by the damage in the lead wire sealing part of a glass bulb | bulb can be prevented. That is, at the end of the glass bulb, when the bottom surface of the puddle portion is in close contact, external impact applied to the lead wire can be suppressed, and furthermore, the bottom surface of the puddle portion has a gap in the radial direction. In this case, the pool portion is not buried in the glass bulb end portion, and damage to the glass bulb end portion due to thermal expansion of the pool portion when solder dipping can be prevented.
In the discharge lamp according to claim 30 of the present invention, a gap is provided between the pool portion and the end portion of the glass bulb, so that when the lead wire and the power supply terminal are welded or when the lamp current increases. In addition, even if the pooled portion of the lead wire generates heat, thermal stress is not applied to the end of the glass bulb due to thermal expansion of the pooled portion. As a result, breakage of the glass bulb end portion is suppressed, and leakage can be prevented.
In the discharge lamp according to the thirty-first aspect of the present invention, since the gap is 0.1 mm to 0.5 mm, for example, even when solder dip is performed on the lead wire in advance, solder is applied to the lead wire in the gap portion. Since it does not adhere, breakage of the glass bulb end is further suppressed, and leakage can be further prevented.
In the discharge lamp according to a thirty-second aspect of the present invention, the puddle portion has a circular cross section perpendicular to the lead wire axis, the maximum diameter of which is larger than the maximum outer diameter of the lead wire, Due to the smaller dimensions, when the power supply terminal is joined to the external lead wire by welding, soldering, etc., it is difficult for heat to be transferred from the external lead wire to the internal lead wire, so that damage to the glass bulb end can be prevented. . Further, when the bottom surface of the pool portion is in close contact with the end portion of the glass bulb, external impact applied to the lead wire can be suppressed.

In the discharge lamp according to a thirty-third aspect of the present invention, when the lead wire is connected to the external lead by soldering or welding or the like, the external lead is smaller than the heat transfer coefficient of the internal lead. Since it is difficult to transfer heat from the inner lead to the internal lead, it is possible to prevent the glass bulb end from being damaged.
In the discharge lamp according to the thirty-fourth aspect of the present invention, the wire diameter of the external lead is smaller than the wire diameter of the internal lead, so that when the power supply terminal is fitted into the socket, the lamp incorporation process or the lamp unit transport process. Thus, even when a force such as vibration or impact is applied to the external lead, the vibration is absorbed by the thin external lead, and damage to the sealing portion of the glass bulb can be prevented.
In the discharge lamp according to the thirty-fifth aspect of the present invention, the lead wire has a surface roughness of 0.2 Ra to 0.8 Ra at least in a portion sealed to the glass bulb. Even if the lead wire provided with the electrode vibrates, the strength of the sealed portion of the lead wire sealed to the glass bulb is high (16% to 40% strength increase compared to 0.1 Ra or less) ) And glass bulb end breakage can be prevented. In addition, since the strength of the sealed portion of the lead wire is high, peeling of the lead wire at the sealed portion of the glass bulb can be prevented. As a result, leakage can be prevented.
In a discharge lamp according to a thirty-fifth aspect of the present invention, the surface of one end portion of the lead wire is 0.2 Ra to 0.8 Ra, and the chamfer dimension is 0.08 mm to 0.15 mm in the radial direction and is axial. Since the length is 0.1 mm to 0.25 mm, the welding strength can be improved. That is, the surface of one end portion of the lead wire is roughened by sandblasting, barrel polishing, or the like, but by making the above dimensions, the surface of the one end surface of the lead wire is suppressed from being reduced to 0.2 Ra to 0 Ra. .8 Ra range can be stably formed, and the hollow electrode and the lead wire can be welded with stable strength by resistance welding or laser welding.
In the discharge lamp according to the thirty-seventh aspect of the present invention, the connecting portion is a part of which is brought into contact with the pooled portion of the lead wire. Positioning can be performed. In addition, when welding is performed with a soft metal, a bending force applied to the lead wire can be suppressed, and a part of the connection portion and the stagnant portion of the lead wire can be electrically and stably connected with a wide connection area.
In the discharge lamp according to the thirty-eighth aspect of the present invention, the connection portion has a larger heat transfer coefficient than that of the lead wire. When fixing the connecting portion of the cylindrical body, the heat at the time of fixing is radiated mainly on the cylindrical body side, so that the glass bulb can be prevented from being damaged by the heat at the time of fixing.
In the discharge lamp according to claim 39 of the present invention, the connection portion has a heat transfer coefficient of 75 W / (m · K) to 435 W / (m · K) and a conductivity of 9 × 10 ⁶ S / m to 65. By being 10 ⁶ S / m, it is possible to improve the weldability and electrical connectivity of the connecting portion of the cylindrical body to the lead wire.
In the discharge lamp according to claim 40 of the present invention, the dark bulb start characteristic can be improved because the glass bulb is formed of a glass material having a sodium oxide content of 3 wt% to 20 wt%. Further, since the cylindrical body is not in contact with the entire outer peripheral surface of the glass bulb facing the lead wire in the glass bulb, mercury vapor is unlikely to collect in the glass bulb surrounded by the entire outer peripheral surface. Generation of amalgam due to the reaction between sodium (Na) eluted on the inner surface and mercury vapor (Hg) can be suppressed, and a decrease in luminance of the fluorescent lamp can be suppressed.
In the discharge lamp according to claim 41 of the present invention, since the glass bulb is formed of a glass material having a sodium oxide content of 5 wt% or more and 20 wt% or less, the dark start time is improved to about 1 second or less. can do.
In the backlight unit according to claim 42 of the present invention, the discharge lamp according to any one of claims 1 to 40 is provided as a light source, so that the lamp can be easily mounted and has a long life. High lamp brightness can be obtained.
A liquid crystal display device according to claim 43 of the present invention comprises a liquid crystal display panel and the backlight unit according to claim 42, wherein the backlight unit is the discharge lamp according to any one of claims 1 to 40. By having an envelope that houses a plurality of lamps, it is possible to obtain lamp brightness while having a long life.

(Description of cold cathode fluorescent lamp)
Hereinafter, a cold cathode fluorescent lamp, for example, a discharge lamp according to a first embodiment of the present invention will be described with reference to the drawings.

  1 is a partially broken perspective view showing a cold cathode fluorescent lamp according to Embodiment 1 of the present invention, FIG. 2 is a partially enlarged perspective view showing a cold cathode fluorescent lamp, and FIG. 3 is a cold cathode. It is an expanded sectional view which shows the one end part of a fluorescent lamp.

As shown in FIGS. 1 to 3, the cold cathode fluorescent lamp 1 is used as a light source of a backlight unit, and is provided inside the glass bulb 10 and both end portions 10 a and 10 b of the glass bulb 10. The hollow electrode 20 and the power supply connected to the outer peripheral surface 10c of both ends 10a and 10b of the glass bulb 10 with the lead wire 22 of the hollow electrode 20 (the lead wire 22 welded to the center of the bottom 24 of the electrode body 21). And a terminal 30.
The glass bulb 10 is obtained by processing a glass tube made of borosilicate glass (SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ —K ₂ O—TiO ₂ ) and has a total length of 730 mm. The glass bulb 10 includes a tubular glass bulb body 11 and a pair of sealing parts 12 formed by thermal processing on both sides in the longitudinal direction of the glass bulb body 11, and both end portions 10 a and 10 b of the glass bulb 10 are made of glass. The outer diameter of the central portion of the valve 10 is larger.
The glass bulb body 11 has an annular shape in cross section, an outer diameter of 4 mm, an inner diameter of 3 mm, and a wall thickness of 0.5 mm. As shown in FIG. 3, the sealing portion 12 has a length W in the tube axis A direction of the glass bulb 10 of 2 mm, and the lead wire 22 of the hollow electrode 20 is sealed.

  The configuration of the glass bulb 10 is not limited to the above configuration. However, in order to make the cold cathode fluorescent lamp 1 elongated, it is desirable that the glass bulb 10 has a small diameter and a small thickness. Therefore, the glass bulb body 11 generally has an inner diameter of 1.4 mm to 6.0 mm and a thickness. Is preferably 0.2 mm to 0.5 mm.

  A phosphor layer 13 is formed on the inner surface excluding both ends of the glass bulb 10. In the present embodiment, as shown in FIG. 3, the end of the phosphor layer 13 faces the outer peripheral surface of the electrode body 21 of the hollow electrode 20, and the bottom 24 of the electrode body 21 and the tube center side of the feeding terminal 30. It is provided so that it may be located between the edge parts. With this configuration, it is possible to prevent ultraviolet rays from leaking directly from the glass bulb body 11.

The phosphor layer 13 is made of, for example, a red phosphor (Y ₂ O ₃ : Eu ³⁺ ), a green phosphor (LaPO ₄ : Ce ³⁺ , Tb ³⁺ ), and a blue phosphor (BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ ). Formed of a rare earth phosphor. The glass bulb 10 is filled with, for example, about 1200 μg of mercury and a mixed gas of neon and argon of about 8 kPa (20 ° C.) as a rare gas at a ratio of Ne: 95 mol% and Ar: 5 mol%. Has been.

  In addition, the structure of the fluorescent substance layer 13, mercury, and a noble gas is not limited to the said structure. For example, krypton may be included in the rare gas. In this case, infrared radiation of the cold cathode fluorescent lamp 1 can be suppressed. Furthermore, it is preferable that krypton is contained in the rare gas within a range of 0.5 mol% or more and 5 mol% or less. In this case, infrared radiation of the cold cathode fluorescent lamp 1 can be suppressed without significantly changing the lamp voltage. For example, argon is in a range of 0 mol% to 9.5 mol%, neon is in a range of 90 mol% to 95.5 mol%, and krypton is in a range of 0.5 mol% to 5 mol%. Furthermore, it is more preferable that krypton is contained in the rare gas within a range of 0.5 mol% to 3 mol%. It is even more preferable that krypton is contained in the rare gas within a range of 1 mol% to 3 mol%.

Moreover, although the borosilicate glass was used for the material of the glass bulb | bulb 10, it is not restricted to this, For example, you may use the soda glass etc. which contain sodium oxide. In this case, it is preferable to provide a protective film between the inner surface of the glass bulb 10 and the phosphor layer 13 for preventing the bonding between mercury and sodium on the inner surface of the glass bulb 10. In consideration of improvement in glass workability and dark start-up characteristics, the glass bulb 10 is preferably formed of a glass material having a sodium oxide content of 3 wt% or more and 20 wt% or less. When the content of sodium oxide is further increased to 5 wt% or more, the dark start-up time under dark conditions is about 1 second or less. Conversely, when the content of sodium oxide exceeds 20 wt%, the glass bulb becomes white due to long-term use, leading to a decrease in brightness, and the strength of the glass bulb 10 itself is reduced. . Further, in consideration of environmental measures, a glass material having an alkali metal content within the range of 3 wt% to 20 wt% and a lead content of 0.1 wt% or less is preferable ( The so-called “lead-free glass”), and more preferably a glass material having a lead content of 0.01 wt% or less. Further, the glass material, in terms of oxide, SiO ₂ is _{60wt% ~75wt%, Al 2 O} 3 is 1wt% ~5wt%, Li ₂ O is 0wt% ~5wt%, _{K 2} O is 3wt% ~11wt% Na ₂ O 3 wt% to 12 wt%, CaO 0 wt% to 9 wt%, MgO 0 wt% to 9 wt%, SrO 0 wt% to 12 wt%, and BaO 0 wt% to 12 wt% Good. In this case, it is possible to provide an environment-friendly cold cathode fluorescent lamp that does not contain a lead component. Furthermore, the glass material, in terms of oxide, SiO ₂ is _{60wt% ~75wt%, Al 2 O} 3 is _{1wt% ~5wt%, B 2 O} 3 is 0wt% ~3wt%, Li ₂ O is 0 wt% ~ 5 wt%, K ₂ O 3 wt% to 11 wt%, Na ₂ O 3 wt% to 12 wt%, CaO 0 wt% to 9 wt%, MgO 0 wt% to 9 wt%, SrO 0 wt% to 12 wt%, BaO 0 wt% It is more preferable to have a composition of 12% to 12% by weight.

Further, the glass material, in terms of oxide, SiO ₂ is _{60wt% ~75wt%, Al 2 O} 3 is 1wt% ~5wt%, Li ₂ O is 0.5wt% ~5wt%, _{K 2} O is 3 wt% ~ 7 wt%, Na ₂ O 5 wt% to 12 wt%, CaO 1 wt% to 7 wt%, MgO 1 wt% to 7 wt%, SrO 0 wt% to 5 wt%, BaO 7 wt% to 12 wt% May be. In this case, it is possible to provide an environment-friendly cold cathode fluorescent lamp that is easy to process into a lamp and does not contain a lead component.

Further, the glass material is in terms of oxide, SiO ₂ is 65 wt% to 75 wt%, Al ₂ O ₃ is 1 wt% to 5 wt%, B ₂ O ₃ is 0 wt% to ₃ wt%, and Li ₂ O is 0.5 wt%. ~5wt%, _{K 2} O is 3wt% ~7wt%, Na ₂ O is 5wt% ~12wt%, CaO is 2wt% ~7wt%, MgO is 2.1wt% ~7wt%, SrO is 0wt% ~0.9wt %, BaO may have a composition of 7.1 wt% to 12 wt%. In this case, it does not contain a lead component, has an electrical insulating property suitable for lighting applications, and can prevent devitrification. Furthermore, the glass material is in terms of oxide, SiO ₂ is 65 wt% to 75 wt%, Al ₂ O ₃ is 1 wt% to ₃ wt%, B ₂ O ₃ is 0 wt% to ₃ wt%, and Li ₂ O is 1 wt% to 3 wt%, K ₂ O 3 wt% to 6 wt%, Na ₂ O 7 wt% to 10 wt%, CaO 3 wt% to 6 wt%, MgO 3 wt% to 6 wt%, SrO 0 wt% to 0.9 wt%, BaO More preferably has a composition of 7.1 wt% to 10 wt%.
The hollow electrode 20 includes an electrode body 21 and a lead wire 22 and is sealed to the sealing portion 12 of the glass bulb 10.

  The electrode body 21 is made of nickel (Ni) and has a bottomed cylindrical shape including a cylindrical portion 23 and a bottom portion 24. The electrode body 21 is not limited to nickel. For example, it is made of iron-nickel alloy, niobium (Nb), tantalum (Ta), titanium (Ti), molybdenum (Mo), tungsten (W), or hafnium (Hf). Can be considered.

  The cylindrical portion 23 has a total length of 5.2 mm, an outer diameter of 2.7 mm, an inner diameter of 2.3 mm, and a wall thickness of 0.2 mm. The hollow electrode 20 is disposed so that the tube axis of the tube portion 23 and the tube shaft of the glass bulb 10 are substantially coincident with each other, and the interval between the outer peripheral surface of the tube portion 23 and the inner surface of the glass bulb 10 is set as follows. Is substantially uniform over the entire outer periphery of the. The length M is 10 mm.

  Specifically, the interval between the outer peripheral surface of the cylindrical portion 23 and the inner surface of the glass bulb 10 is 0.15 mm. Thus, when the interval is narrow, discharge does not enter the interval and discharge occurs only inside the hollow electrode 20. Therefore, the sputtered material that is scattered by the discharge is less likely to adhere to the inner surface of the glass bulb 10, and the cold cathode fluorescent lamp 1 has a long life. On the other hand, since the discharge does not go to the lead wire 22 side, the lead wire 22 is not easily heated by the discharge.

  In addition, although the space | interval of the outer peripheral surface of the cylinder part 23 and the inner surface of the said glass bulb 10 does not necessarily need to be 0.15 mm, in order to prevent discharge from entering the said space | interval, it is 0.2 mm or less. It is preferable.

  An electron-emitting material layer (not shown) may be formed on the surface of the electrode body 21. In this case, the lamp voltage can be lowered compared to a lamp not provided with an electron emissive material layer. Specifically, the electron emissive material layer is formed, for example, on the inner surface of the electrode. The electron emissive material layer includes, for example, a rare earth element. This is because the cold cathode fluorescent lamp is effective in reducing the lamp voltage. Furthermore, the rare earth element is more preferably one or more of lanthanum (La) and yttrium (Y).

The electron-emitting material layer may be any one of silicon (Si), aluminum (Al), zirconium (Zr), boron (B), zinc (Zn), bismuth (Bi), phosphorus (P), and tin (Sn). It is preferable that 1 or more types are included. In this case, the lamp voltage reduction effect can be further sustained.
Furthermore, a cesium (Cs) compound may be included in the electron-emitting material layer. In this case, the dark start characteristics of the lamp can be further improved. In addition to the electron radioactive material layer, a cesium compound may be attached to the inner surface or the outer surface of the electrode body 21. As the cesium compound, for example, it is preferable to use at least one of cesium sulfate, cesium aluminate, cesium niobate, cesium tungstate, cesium molybdate, and cesium chloride. The cesium compound is more preferably attached to the outer peripheral surface of the cylindrical portion 23 of the electrode. In this case, in the manufacturing process of the cold cathode fluorescent lamp 1, it is possible to appropriately activate the cesium compound. Furthermore, it is still more preferable that it adheres to the front-end | tip part by the side of the lamp | ramp center part in the outer peripheral surface of the cylinder part 23 of an electrode.
The lead wire 22 is an internal lead wire 25 made of tungsten (W), which is substantially the same material as the thermal expansion coefficient of the glass bulb 10, and an external lead made of nickel that is thin with the internal lead wire 25 and easily adheres to solder or the like. The wire 26 is welded and joined. In the joint portion of the lead wire 22, a puddle portion 27 that is smaller than the outer diameter of the glass bulb 10 and larger than the outer diameter of the inner lead wire 25 is opposed to both end faces of the glass bulb 10, and is attached to both ends of the glass bulb 10. It is provided so that a bottom part may closely_contact | adhere. That is, the external lead wire 26 and the pool portion 27 are located outside the outer surface of the glass bulb 10.

With this configuration, the dimension from the pool portion 27 to the hollow electrode 20 can be made constant, that is, the gap ε (the length in the axial direction of the cylindrical body) between the bottom of the hollow electrode 20 and the inner surface of the glass bulb 10 facing the bottom. ) Can be reduced to about 1 mm to increase the effective light emission length L. Further, when the protruding portion of the external lead wire 26 collides with the outside, the force applied to the pool portion 27 is absorbed at both ends of the glass bulb 10, so that the glass bulb 10 sealed with the internal lead wire 25 is sealed. Leakage due to breakage of the landing portion 12 can be prevented.
The pool portion 27 is formed of the same nickel material as that of the external lead wire 26. However, the present invention is not limited thereto, and is formed by, for example, Fe—Ni alloy, Cu—Ni alloy, jumet wire, iron material, or nickel plating on the surface thereof. It is conceivable to make it a thing. Further, the pool portion 27 of the external lead wire 26 has a circular cross section orthogonal to the axis of the lead wire 22 (cross section orthogonal to the tube axis A), and the maximum diameter is the maximum outer diameter of the internal lead wire 25. The size is preferably larger and smaller than the maximum outer diameter of the glass bulb 10. However, the pool portion 27 is not always necessary.
The internal lead wire 25 has a substantially circular cross section, a total length of 3 mm, a wire diameter of 0.8 mm, and a surface roughness of 0.4 Ra. The internal lead wire 25 has an end on the external lead wire 26 side sealed to the sealing portion 12 of the glass bulb 10 and an end opposite to the external lead wire 26 side on the outside of the bottom 24 of the electrode body 21. It is joined to the approximate center of the side.
The surface roughness of the internal lead wire 25 is not limited to 0.4 Ra, but is preferably 0.2 Ra to 0.8 Ra from the viewpoint of sufficient sealing strength of the sealing portion 12 and no leakage. That is, in recent years, there has been a demand for higher brightness, and when the lamp current of the cold cathode fluorescent lamp is increased to 20 mA (about three times the conventional lamp current), the sealing strength of the sealing portion 12 becomes insufficient and leakage occurs. Sometimes. Therefore, it is operated at 3.5 mA (conventional lamp current) to 22 mA (about three times as compared with the conventional lamp current), and the surface roughness of the internal lead wire 25 is 0.08 Ra, 0.2 Ra, 0.33 Ra, 0 Experiments were performed when changing to .52Ra, 0.80Ra, and 0.99Ra. As a result, when the surface roughness was 0.08 Ra, the bead 12 (sealed portion) might leak due to insufficient sealing strength. Also, when the surface roughness is 0.2Ra, 0.33Ra, 0.52Ra, 0.80Ra and 0.99Ra, the sealing strength (strength UP of 16% to 40% compared to 0.1Ra or less) The problem did not occur. However, when the surface roughness is 0.99 Ra, air bubbles may be generated in the sealing portion 12, and this is because the surface irregularities of the portion sealed by the glass bulb 10 of the lead wire 22 are too large ( This is probably because if the surface is too rough, glass does not enter the recess and bubbles are likely to be generated. Such bubbles are not preferable because they may cause leakage.
One end portion of the lead wire 22 is welded and fixed to the center portion of the bottom 24 of the electrode body 21, the surface of the one end portion is 0.2 Ra to 0.8 Ra, and the chamfer dimension is 0 in the radial direction. When the length in the axial direction is 0.1 mm to 0.25 mm at 0.08 mm to 0.15 mm, the welding strength can be improved.
The surface roughness Ra is set to 5 times along the lead axis direction by using a scanning confocal infrared laser microscope (OLYMPUS CORPORATION, LEXT.OLS3000). It measured and calculated | required from the average value.
The external lead wire 26 is a protruding portion that protrudes from the outer surface of the glass bulb 10 toward the tube axis A direction, and is joined to the power supply terminal 30. The external lead wire 26 has a total length (length including the puddle) of 5 mm, and the axial center of the external lead wire 26 and the tube axis A of the glass bulb 10 substantially coincide with each other.
The total length of the external lead wire 26 is preferably 8 mm or less in order to reduce the damage of the sealing portion 12. The external lead wire 26 has a substantially circular cross section, and the wire diameter is 0.6 mm, which is narrower than the internal lead wire 25. In other words, when the cold cathode fluorescent lamp 1 is attached to the backlight unit 1000 shown in FIG. 20, for example, when the cold cathode fluorescent lamp 1 is attached to the backlight unit 1000 shown in FIG. There is little possibility that the sealing part 12 will be cracked by the stress applied to.
The power supply terminal 30 has a conductive cylindrical body 31 provided so as to contact and surround the outer peripheral surface 10c of the glass bulb 10 except for both end portions 10a and 10b larger than the outer diameter of the central portion of the glass bulb 10. Is.
Specifically, the power supply terminal 30 is formed of a thin metal member made of stainless steel having a length P of 6 mm and a thickness of 0.1 mm, for example, from the cylindrical body 31. A cylindrical body axial direction lead wire 22 side is provided, and a connecting portion 31b connected to a part of the lead wire 22 is provided. The cylindrical body 31 is provided so as to be externally attached to and generally surrounded by the outer peripheral surface of the end of the glass bulb 10 excluding both end portions 10a and 10b larger than the outer diameter of the central portion of the glass bulb 10. The inner surface of the cylindrical body 31 is in close contact with the outer peripheral surface 10c of the glass bulb 10 facing the hollow electrode 20. With this configuration, since the hollow electrode 20 is heated, mercury on the inner surface of the glass bulb 10 facing the hollow electrode 20 is difficult to accumulate, and the mercury vapor in the discharge path is insufficient, resulting in a decrease in lamp brightness or a rise in lamp brightness. Is less likely to occur.
Then, a strip-shaped lead-out portion 31a extending outward from one end of the cylindrical body 31 in the axial direction of the cylindrical body, and a connection portion provided at the tip of the lead-out portion 31a and connected to a part of the lead wire 22 31b, that is, the power supply terminal 30 is obtained by connecting the cylindrical body 31 and the connection portion 31b via the lead-out portion 31a.
As shown in FIG. 2, the cylindrical body 31 has a slit portion 32 in the axial direction, has a substantially C-shaped cross section, and the dimensional tolerance of the outer shape of the glass bulb by the elastic force of the substantially C-shaped portion. And is held on the outer peripheral surface 10 c of the glass bulb 10.
For example, the connection portion 31 b is formed with a U-shaped portion so as to approach a part of the outer peripheral surface of the lead wire 22, and is caulked with respect to the lead wire 22. As a result, the electrical connection state is maintained (stable connection), and the power supply terminal 30 can be positioned in the axial direction with respect to the glass bulb 10.

After the caulking, the caulking connection portion 31b may be covered with a soft metal such as solder or solder, or the connection strength may be further increased by laser welding or the like.
When the power supply terminal 30 having the cylindrical body 31 having the above-described configuration is fitted into a set of sockets 1600 of the backlight unit shown in FIG. 21, which will be described below, a lamp incorporation process or a lamp unit transport process. Even when a force such as vibration or impact is applied to the power supply terminal 30 of the cold cathode fluorescent lamp 1, the sealing portion of the glass bulb 10 and the outer peripheral surface of the glass bulb 10 to which the power supply terminal 30 is attached are provided. Cracks can be prevented from occurring.
The cylindrical body 31 is not limited to the above-mentioned thickness and stainless steel material, but is made of, for example, tantalum, nickel, Kovar, molybdenum, tungsten, corrosion resistance and spring having a thickness of 0.1 to 0.5 mm. From the viewpoint of property, it may be formed of a member such as phosphor bronze. In order to suppress the heat radiation effect of the power supply terminal 30 to be small, it is preferable that the region where the cylindrical body 31 is formed is as narrow as possible, and the length of the power supply terminal 30 in the tube axis A direction (the cylindrical body axis direction). P is preferably 19 mm or less. In addition, when the length P is larger than the tip of the electrode body 21 on the center side of the glass bulb body 11, the effective light emission length is shortened. It is more preferable that the length is 10 mm or less, which is shorter than the front end portion of the valve main body 11.
The discharge lamp according to any one of claims 28 to 36, wherein:
The connecting portion 31b preferably has a heat transfer coefficient larger than that of the lead wire 22. In other words, the connection portion 31b has a larger heat transfer coefficient than the lead wire 22, so that the connection portion 31b of the cylindrical body 31 is connected to the lead wire 22 by using a soft metal such as solder or solder, laser welding, resistance welding, or the like. In the case of fixing, since the heat at the time of fixing is mainly dissipated on the cylindrical body 31 side, the glass bulb can be prevented from being damaged by the heat at the time of fixing.
The connecting portion 31b, the heat transfer coefficient at 75W / (m · K) ~435W / (m · K), and the conductivity is at ^{9 × 10 6 S / m~65 ×} 10 6 S / m Thereby, the weldability and electrical connectivity of the connecting portion of the cylindrical body can be improved with respect to the lead wire. In the heat transfer coefficient 75W / (m · K) ~435W / (m · K), and, as a conductivity is ^{9 × 10 6 S / m~65 ×} 10 6 S / m material, silver (Thermal conductivity 429 W / (m · K), conductivity 63 × 10 ⁶ S / m), copper (thermal conductivity 401 W / (m · K), conductivity 59.6 × 10 ⁶ S / m), gold (Thermal conductivity 317 W / (m · K), conductivity 45.2 × 10 ⁶ S / m), aluminum (thermal conductivity 237 W / (m · K), conductivity 37.7 × 10 ⁶ S / m) , iron (thermal conductivity 80.2W / (m · K), conductivity of ^{9.93 × 10 6 S / m)} , nickel (thermal conductivity 90.7W / (m · K), conductivity 14.3 × 10 ⁶ S / m), tungsten (thermal conductivity 174W / (m · K), conductivity of ^{18.9 × 10 6 S / m)} , molybdenum (thermal conductivity 138W / (m · K), Conductivity 18.7 × ¹⁰ 6 S / m), and the like.
Further, the lead wire 22 preferably has an external lead 26 smaller than the heat transfer coefficient of the internal lead 26. That is, the lead wire 22 has the external lead 26 smaller than the heat transfer coefficient of the internal lead 25, so that when the power supply terminal 30 is joined to the external lead 26 by soldering or welding, the external lead 26 to the internal lead 25. Since it is difficult to transfer heat to the glass bulb, it is possible to prevent the glass bulb end portion 10b from being damaged.

The cold cathode fluorescent lamp 1 is operated at a lighting frequency of 40 to 100 kHz and a lamp current of 3 to 25 mA. When the lamp current is increased to 25 mA, in order to reduce the temperature of the hollow electrode 20 from the viewpoint of reducing the sputtering amount while considering the effective light emission length, for example, the length P of the power supply terminal 30 is reduced to 19 mm. In addition, it is preferable that each length of the cylindrical body 31 is increased up to 15 mm.
As described above, the cold cathode fluorescent lamp 1 according to the present invention has been specifically described based on the embodiment. However, the cold cathode fluorescent lamp 1 according to the present invention is not limited to the above embodiment. For example, the cold cathode fluorescent lamp is not limited to a straight tube shape, and may be a bent cold cathode fluorescent lamp such as a U shape, an L shape, or a C shape. Further, the configuration of the power supply terminal 30 is not limited to the above configuration, and for example, a configuration as shown in Modifications 1 to 16 described below can be considered. In the drawings of the following modifications, the same components as those of the power supply terminal 30 described above are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 4 is an enlarged cross-sectional view showing one end of the cold cathode fluorescent lamp according to the first modification.

  Modification 1 differs from the first embodiment in the configuration related to the pool portion 27. Specifically, the pool portion 27 is embedded in the recessed portion 12a provided in the end portion 12 of the glass bulb 10 in a state where the whole portion is immersed, and the bottom surface thereof is in close contact with the bottom surface of the recessed portion 12a. And the peripheral surface is maintaining the distance B in the lead wire radial direction between the side peripheral surfaces of the recessed part 12a.

  With this configuration, since the bottom surface of the pool portion 27 is in close contact with the end portion 12 of the glass bulb 10, external impact applied to the lead wire 22 can be suppressed. Further, since the bottom surface of the pool portion 27 has a gap in the lead wire radial direction, even if the pool portion 27 is thermally expanded due to the connection portion 31b being fixed to the lead wire 22 with solder, brazing, or the like. The breakage of the end 12 of the glass bulb 10 can be prevented.

  FIG. 5 is an enlarged cross-sectional view showing one end of a cold cathode fluorescent lamp according to Modification 2.

The modification 2 differs from the first embodiment in the configuration related to the pool portion 27. Specifically, the pool portion 27 is disposed with a gap of a distance C between the end portion 12 of the glass bulb 10 and, for example, welding between the lead wire 22 and the power supply terminal 30 is performed. When the bonding or lamp current increases, the pool portion 27 of the lead wire 22 generates heat. However, since a gap is provided between the end portion 12 of the glass bulb 10, the glass bulb is heated by the thermal expansion of the pool portion 27. No thermal stress is applied to the end portions 12 of the ten. As a result, the breakage of the end portion 12 of the glass bulb 10 can be suppressed and the occurrence of leakage can be prevented. When the gap (distance) C is 0.1 mm to 0.5 mm, for example, even when solder dipping is performed on the lead wire 22 in advance, solder does not adhere to the lead wire 22 in the gap portion. Therefore, the breakage of the end portion 12 of the glass bulb 10 is further suppressed, and the occurrence of leak can be prevented.
FIG. 6 shows a cross-sectional view of the power supply terminal 40 of the cold cathode fluorescent lamp according to the third modification.

  The third modification is different from the first embodiment in that the connection portion 41b of the power supply terminal 40 is formed by bending from the leading end of the lead-out portion 41a so as to make surface contact with one end surface of the lead wire 22, and the surface contact portion. 41c is different from the lead wire 22 in welding connection. According to this configuration, a force is applied in the direction of the central axis of the lead wire 22 by the connecting portion 41b, so that a bending force applied to the lead wire 22 can be suppressed. Further, the surface contact portion 41c and the lead wire 22 can be stably connected using laser welding, resistance welding, or a soft metal such as solder or solder, and the power supply terminal 40 is connected to the glass bulb 10. Can be positioned in the axial direction.

  FIG. 7 is a cross-sectional view of the power supply terminal 50 of the cold cathode fluorescent lamp according to the fourth modification.

  The modification 4 is formed by bending from the leading end of the lead-out portion 51a so that the connection portion 51b of the power supply terminal 50 is close to or in contact with a part of the outer peripheral surface of the lead wire 22 in the first embodiment. The difference is that the planar contact portion 55 and the lead wire 22 are connected by welding, and the bent end surface of the connecting portion 51 b facing the padding portion 27 is in contact with the padding portion 27. According to this configuration, the bending force applied to the lead wire 22 is suppressed, and the flat contact portion 55 and the lead wire 22 are stably connected using laser welding, resistance welding, or a soft metal such as solder or solder. can do. Further, the power supply terminal 50 in the axial direction can be positioned with respect to the glass bulb 10.

  FIG. 8 is a cross-sectional view of the power supply terminal 60 of the cold cathode fluorescent lamp according to the fifth modification.

  Modification 5 is different from the first embodiment in that the connection portion 61b of the power supply terminal 60 is bent from the front end of the lead-out portion 61a so that the connection portion 61b is in surface contact with the end surface of the padding portion 27. A point where a through hole 62 (or a notch) is provided so that the wire 22 is inserted, and after the surface contact, the connecting portion 61b, the lead wire 22 and the padding portion 27 are connected to a soft metal such as solder or solder. The difference is that they are welded and connected. According to this configuration, a force is applied to the pooled portion 27 of the lead wire 22 by the connecting portion 61b, so that the bending force applied to the lead wire 22 can be suppressed. Further, the thickened portion 27 having a wide contact surface and the plate surface of the connecting portion 61b can be stably connected using a soft metal such as solder or solder. Further, since the power supply terminal 60 can be positioned at the position of the thickened portion 27 of the glass bulb 10, the length of the lead wire 22 can be shortened and the total length of the cold cathode fluorescent lamp can be shortened.

  FIG. 9 shows a cross-sectional view of the power supply terminal 70 of the cold cathode fluorescent lamp according to Modification 6.

The modified example 6 is different from the first embodiment in that the connecting portion 71b of the power supply terminal 70 is bent from the leading end of the lead-out portion 71a so that the connecting portion 71b contacts the end surface of the padding portion 27, and the lead wire After the contact, the connecting portion 71b is caulked, and then the connecting portion 71b, the lead wire 22 and the padding portion 27 are soldered or brazed. It is different in that it is welded and connected using a soft metal such as. According to this configuration, a force is applied to the pool portion 27 of the lead wire 22 by the connecting portion 71b, so that the bending force applied to the lead wire 22 can be suppressed. In addition, the thickened portion 27 having a wide contact surface and the cylindrical portion 72 of the connecting portion 71b can be stably connected using a soft metal such as solder or solder. Further, since the power supply terminal 70 can be positioned at the position of the thickened portion 27 of the glass bulb 10, the length of the lead wire 22 can be shortened and the total length of the cold cathode fluorescent lamp can be shortened.
Note that the connection between the thickened portion 27 having a wide contact surface and the cylindrical portion 72 of the connecting portion 71b is replaced with the soft metal such as solder or brazing, and the connection is further stabilized, for example, laser welding, resistance welding, etc. Can also be done.
FIG. 10 is a perspective view of a power supply terminal 80 provided at the end of the cold cathode fluorescent lamp according to the modified example 7.

  Modification 7 is different from the first embodiment in that the connecting portion 81b of the power supply terminal 80 extends in parallel with the tube axis A from the cylindrical wall of the cylindrical body 81 and is folded at a right angle in the middle. The difference is that the lead-out part 81a and the elastic clamping part 83 provided at the extending end of the lead-out part 81a are configured.

  Specifically, the elastic clamping part 83 has a base part 83a that is a rectangular plate-like part orthogonal to the tube axis A, and a pair of elastic clamping pieces 83b and 83c extending from the base part 83a. In addition, each of the elastic clamping pieces 83b and 83c has a strip shape extending toward the cylindrical body 81 from the opposing side portion in the base portion 83a. The elastic clamping pieces 83b and 83c are bent in a “<” shape toward the inside (toward the tube axis A), and elastically hold the lead wire 22 between the tops of the bent portions. The pressing force of each of the pair of elastic clamping pieces 83b and 83c is at least 100 g with respect to the lead wire 22, and the lead wire 22 is clamped and connected.

  According to this configuration, the power supply terminal 80 can be positioned with respect to the glass bulb 10 by bringing the base 83 a into contact with the tip of the lead wire 22.

  In addition, since the lead wire 22 makes point contact with the two points of the elastic clamping pieces 83b and 83c, the lead wire 22 is effective between the tops even if the lead wire 22 is slightly inclined with respect to the glass bulb 10. Therefore, it is difficult to apply an excessive force to the lead wire 22.

Furthermore, since the elastic clamping part 83 is excellent in the insertion / removal property of the lead wire 22, the attachment / detachment property to the glass bulb 10 of the electric power feeding terminal 80 improves.
In addition, although the lead wire 22 contacts the two points of the elastic clamping pieces 83b and 83c, the power supply terminal 80 may be contacted at two or more points, for example, the circumference of the power supply terminal is 3 etc. Even if the outer peripheral surface of the lead wire 22 is elastically clamped by the three strip-shaped lead-out portions and the connection portions provided at the leading ends of the lead-out portions from the equally divided circumferential end portions, Good.

  FIG. 11 is a perspective view of a power supply terminal 90 provided at the end of the cold cathode fluorescent lamp according to Modification 8.

  Modification 8 is different from the first embodiment in that the connection portion 91b of the power supply terminal 90 extends from the cylindrical wall of the cylindrical body 91 in the direction of the tube axis A and extends from the strip-shaped extraction portion 91a and the extraction portion 91a. The point which has the elastic clamping part 93 formed out is different.

  Specifically, the elastic clamping part 93 has basically the same configuration as the elastic clamping part 83 described above. That is, it comprises a pair of elastic clamping pieces 93b and 93c extending from the base portion 93a. What is characteristic is that one strip-like portion extending from the cylindrical body 91 including the lead-out portion 91a is bent at a predetermined position in the longitudinal direction. Each of the pair of elastic clamping pieces 93b and 93c has a pressing force of at least 100 g with respect to the lead wire 22, and is connected by clamping the lead wire 22.

  According to this configuration, the amount of material used in the connection portion 91b of the power supply terminal 90 can be reduced compared to the seventh modification, and the overall weight can be reduced.

  Moreover, the point which is excellent in the insertion property to the elastic clamping part 93 of the lead wire 22 is the same as that of the said modification 7. On the other hand, the lead wire 22 has a structure that is difficult to be removed from the elastic clamping portion 93. When the lead wire 22 is pulled out from the elastic clamping portion 93, the lead-out portion 91b bends inward (toward the tube axis A). As a result, the elastic piece portion 93 c is similarly displaced inward and presses the lead wire 22, and the frictional force increases between the elastic piece portion 93 c and the lead wire 22. Therefore, once the power supply terminal 90 is attached to the glass bulb 10, it can be suitably used when it is not necessary to remove it.

Furthermore, since the elastic clamping part 93 is excellent in the insertion / removal property of the lead wire 22, the attachment / detachment property to the glass bulb 10 of the electric power feeding terminal 90 improves.
FIG. 12 is an enlarged cross-sectional view showing one end portion of the power supply terminal 100 provided at the end portion of the cold cathode fluorescent lamp according to Modification 9.

  Modification 9 is greatly different from the first embodiment in that there is a step on the outer peripheral surface of the cylindrical body 101.

Specifically, the cylindrical body 101 of the power supply terminal 100 includes a first cylindrical portion 110 and a second cylindrical portion 120 extending from the first cylindrical portion 110 to the lead axis side in the tube axis A direction. The second cylinder part 120 has a larger outer diameter than the first cylinder part 110.
According to this configuration, when the cold cathode fluorescent lamp is installed in a pair of sockets 1600 of the backlight unit described below, a step caused by a difference in the outer diameter between the first tube portion 110 and the second tube portion 120. A part of the end face 1640 of the socket 1600 on the lead axis side of the socket 1600 can be pressed against the socket 130, and the lamp can be easily positioned in the pipe axis A direction.

Since the thickness of the 1st cylinder part 110 and the 2nd cylinder part 120 is the same, the 2nd cylinder part 120 has a larger internal diameter than the 1st cylinder part 110. FIG. Specifically, since the second cylinder part 120 is formed larger than the inner diameter and the outer diameter of the end of the glass bulb 10 than the first cylinder part 110, the heat radiation area is larger than that of the first embodiment, The heat dissipation can be improved.
FIG. 13 is an enlarged view showing one end portion of the power supply terminal 200 provided at the end portion of the cold cathode fluorescent lamp according to the modified example 10.

  As shown in FIG. 13A, the modification 10 is greatly different from the first embodiment in that the inner surface of the end portion 250 on the tube axis A direction hollow electrode side of the tubular body 201 is chamfered. . Specifically, the chamfer is formed in a taper shape over the entire circumferential direction at the end 250 of the tubular body 201 on the tube axis A direction hollow electrode side.

With this configuration, damage to the surface of the glass bulb 10 when the feed terminal 200 is inserted into the glass bulb 10 is suppressed, and the feed terminal 200 can be easily attached to the glass bulb 10.
FIG. 14 is an enlarged cross-sectional view showing one end portion of the power supply terminal 300 provided at the end portion of the cold cathode fluorescent lamp according to the modification 11.

  Modification 11 is significantly different from the first embodiment in that the end 350 on the tube axis A direction hollow electrode side of the cylindrical body 301 is formed in a trumpet shape. With this configuration, since the inner diameter of the end portion 350 is increased, damage to the surface of the glass bulb 10 is suppressed when the feeding terminal 300 is inserted into the glass bulb 10, and the feeding terminal 300 is easily attached to the glass bulb 10. Can be installed.

  FIG. 15 is a perspective view showing a power supply terminal 400 of a cold cathode fluorescent lamp according to Modification 12.

  The modification 12 is greatly different from the first embodiment in the configuration of the tubular body 401. As shown in FIG. 15, the cylindrical body 401 has a plurality of elastic tongues 420 provided along the circumferential direction, and the outer peripheral surface 10 c of the glass bulb 10 is sandwiched by the plurality of elastic tongues 420. Yes. Specifically, the cross section is substantially C-shaped, and a cylindrical body portion 410 having a slit portion 430 in the cylindrical body axial direction, and a plurality of (books) extending from one end of the cylindrical body portion 410. In the example, the elastic tongue piece 420 has six strips. The elastic tongue piece 420 has a plurality of (six in this example) slit portions 432 extending from one end of the cylindrical body portion 410 along the axial direction of the cylindrical body to a predetermined depth at equal intervals in the circumferential direction. It is formed by. Since one of the slit parts 432 is connected to the slit part 430 of the cylindrical body part 410, the dimensional tolerance of the outer shape of the glass bulb 10 can be absorbed by the elastic force of the substantially C-shaped part, and the power supply terminal 400 can be absorbed. It can be held on the outer peripheral surface of the glass bulb 10.

  Each of the elastic tongue pieces 420 is bent inward as a whole from the vicinity of the proximal end portion on the cylindrical body 410 side, and the inner surface of the distal end portion 450 of the elastic tongue piece 420 is chamfered. Good. Thus, when the power supply terminal 400 is extrapolated to the cold cathode fluorescent lamp, the outer peripheral surface of the glass bulb 10 is not damaged at the corner of the tip of the elastic tongue piece 420, and it is easy to insert into the end portion 12 of the glass bulb 10. Therefore, the work of attaching the power supply terminal to the end of the glass bulb can be performed smoothly.

  As shown in FIG. 15, when the power supply terminal 400 having the above configuration is extrapolated to the end portion of the glass bulb 10, each elastic tongue piece 420 comes into contact with the outer peripheral surface of the glass bulb 10, and the entire elastic tongue piece 420 is Then, the glass bulb 10 is elastically bent (elastically deformed) outwardly in the radial direction of the glass bulb 10 with the base end portion as a base point, and the glass bulb 10 is sandwiched by its restoring force. Thereby, the glass bulb 10 is positioned in the cylindrical body portion 410 in a state in which the cylindrical body portion 410 and the axial center are substantially matched.

  With this configuration, an equally distributed load is applied to the entire outer peripheral surface of the tubular body 401, so that the glass bulb 10 can be prevented from cracking. Further, since the adhesion between the inner surface of the cylindrical body 401 and the outer peripheral surface of the glass bulb 10 is improved, the feed terminal 400 is attached to the glass bulb 10 in the tube axis direction after the feed terminal 400 is attached to the glass bulb 10. It can be made difficult to move.

  Needless to say, the shape, number, arrangement position, and the like of the elastic tongue piece 420 and the slit portion 430 are not limited to those described above. In short, any configuration that can elastically support the glass bulb 10 in the tubular body 401 may be used.

  FIG. 16 is a perspective view showing one end of a power supply terminal 500 provided at the end of a cold cathode fluorescent lamp according to Modification 13.

  The modified example 13 is greatly different from the first embodiment in the configuration of the cylindrical body 501. The cylindrical body 501 is a linear or belt-like elastic material 502 formed of a metal material, and is wound in a spiral shape in close contact with or apart from the cylindrical body axial direction. According to this structure, since the cylindrical body 501 can be formed with the raw material itself, material loss can be reduced.

In this modification, the cylindrical body 501 is formed of a band-shaped elastic material, and extends from the first cylindrical portion 510 and the first cylindrical portion 510 to the cylindrical body axial direction lead wire side. The second cylinder part 520 has a larger outer diameter than the first cylinder part 510. The inner surface of the first tube portion 510 is in close contact with the outer peripheral surface of the glass bulb 10, and the glass bulb 10 is held by the first tube portion 510. On the other hand, the inner surface of the second cylindrical portion 520 is not in contact with the outer peripheral surface of the glass bulb 10, and there is a gap between these surfaces. The elastic material 502 is formed, for example, with a gap 505 in the axial direction of the cylindrical body and a gap between the belts in order to improve heat dissipation of the cylindrical body 501.
FIG. 17 is a perspective view showing one end portion of the power supply terminal 600 provided at the end portion of the cold cathode fluorescent lamp according to the modification 14.

The modified example 14 is greatly different from the first embodiment in the configuration of the cylindrical body 601. The cylindrical body 601 has a plurality of convex portions 610 formed on the outer peripheral surface thereof in the circumferential direction (ring-shaped convex portion). Although the convex portion 610 has been described as being formed in the circumferential direction, the convex portion 610 may be formed in a spiral direction with respect to the axial direction or the tube axis instead of the circumferential direction.
According to this configuration, since the outer diameter of the cylindrical body 601 can be substantially increased by the plurality of convex portions 610, the cylindrical body 601 can be matched with the socket 1600. In addition, since the surface area of the cylindrical body 601 can be increased, heat dissipation can be improved.
FIG. 18 is a perspective view showing one end of a power supply terminal 700 provided at the end of a cold cathode fluorescent lamp according to Modification 15.

  In the modified example 15, the first embodiment is engaged with each of a part of the pair of end edges 732a and 732b facing each other across the slit 732 of the cylindrical body 701 across the slit 732. The point which provided a pair of engaging part differs greatly.

  Specifically, the pair of engaging portions are provided at a position facing the concave portion 735b formed by cutting out a part of one end edge 732b facing the slit portion 732 and the concave portion 735b on the other end edge 732b. And a convex portion 735a having a tip fitted into the concave portion 735b.

  According to this configuration, since the movement of the convex portion 735a in the direction of the tube axis A is restricted by the concave portion 735b, the tubular body 31 is deformed such that the pair of end edges 732a and 732b are displaced from positions facing each other. It is difficult and the shape of the cylindrical body 701 is stable. In addition, the dimensional tolerance of the outer shape of the glass bulb can be absorbed by the width of the slit portion 732.

In addition, the recessed part 735b and the convex part 735a should just be a shape which can control that a pair of edge moves from the position which mutually opposed. For example, the concave portion 735b is not limited to a shape in which the outer peripheral surface of the cylindrical body 701 is cut out in a square shape, and the convex portion 735a is not limited to a shape in which the outer peripheral surface of the cylindrical body 701 is protruded in a quadrangular shape. It may be cut out or protruded. Moreover, a pair of engaging part may be provided in multiple pairs.
FIG. 19 is an enlarged cross-sectional view showing one end portion of a power supply terminal 800 provided at an end portion of a cold cathode fluorescent lamp according to Modification 16.

  Modification 16 is different from the first embodiment in that there are two stepped portions on the outer peripheral surface of the cylindrical body 811 and an elastic tongue piece 860 provided with a plurality of cylindrical bodies 811 along the circumferential direction. The point which clamps the outer peripheral surface of the glass bulb | bulb 10 by these some elastic tongue pieces 860 differs greatly.

  Specifically, the tubular body 811 of the power supply terminal 800 includes a first tubular portion 833 and a pair of second tubular portions 834 and 835 extending from the first tubular portion 833 to both sides in the tube axis A direction. The second cylinder parts 834 and 835 have a larger outer diameter than the first cylinder part 833, respectively. In addition, the cylindrical body 811 is a part of the cylindrical body 811 that is bent, protrudes radially inward on the inner surface thereof, and faces the outer peripheral surface of the hollow electrode 20 in the glass bulb 10. And an elastic tongue piece 860 which is a clamping member for clamping the glass bulb 10. Further, the elastic tongue piece 860 is a plurality of band-like bodies formed by extending from the second tube portion 834 to the second tube portion 835 and bending from the second tube portion 834 to the glass bulb 10 side. Is different.

  According to this configuration, in the same manner as in the ninth modification example, the step 836 caused by the outer diameter difference between the first tube portion 833 and the second tube portion 834 has a socket (not shown) in the tube axis A direction lead wire side. It is possible to press a part of the end face of the lamp, and it is easy to position the lamp in the direction of the tube axis A. Further, when the socket is fitted into the first cylindrical portion 833 which is a recessed portion between the two steps 836 and 837, the position-adjusted lamp is displaced in the direction of the tube axis A so that the two steps 836 and 837 are moved. Therefore, the surface of the cylindrical body 811 is less damaged by friction with the socket. The positioning is preferably performed only at one of the power supply terminals 800 at both ends of the glass bulb 10 because the glass bulb 10 has a dimensional variation in the tube axis A direction due to thermal expansion or the like.

Since the thickness of the 1st cylinder part 833 and the 2nd cylinder part 834,835 is the same, the 2nd cylinder part 834,835 has a larger internal diameter than the 1st cylinder part 833. Further, while the inner surface of the first tube portion 833 and the outer peripheral surface of the glass bulb 10 are in close contact, the inner surface of the second tube portions 834 and 835 and the outer peripheral surface of the glass bulb 10 have a gap. . Further, the base end portion of the elastic tongue piece 860 is disposed in the first tube portion 833. Thus, the socket is easily pressed against the steps 836 and 837.
The elastic tongue piece 860 is provided so as to extend from the second tube portion 834 to the second tube portion 835 side, but is not limited thereto, and extends from one end side of the first tube portion 833 to the other end side. In addition, a plurality of strips formed by bending from the one end side to the glass bulb 10 side may be used.

  As described above, the power supply terminals provided at both ends of the glass bulb 10 are not limited to the shapes of the first embodiment and the modifications 1 to 16, but may be a combination thereof.

  In addition, the power supply terminal is not limited to the same shape at both ends, and may be combined with any of the above-described first embodiment and modifications 1 to 16.

(Description of backlight unit)
FIG. 20 is an exploded perspective view showing a schematic configuration of a backlight unit and the like according to an embodiment of the present invention, and FIG. 21 is a diagram for explaining a mounting state of the cold cathode fluorescent lamp.

  As shown in FIG. 20, a backlight unit 1000 according to an embodiment of the present invention is a direct-type backlight unit for a liquid crystal television, and its structure is basically the same as that of a conventional backlight unit. Follow.

  The backlight unit 1000 includes an envelope 1100, a diffusion plate 1200, a diffusion sheet 1300, and a lens sheet 1400, and is used by being arranged on the back surface of the liquid crystal panel 1500.

  The envelope 1100 is a box made of white polyethylene terephthalate (PET) resin, and as shown in FIG. 20 or FIG. 21, a substantially square reflecting plate 1110 and side plates 1120 surrounding the periphery of the reflecting plate 1110. 1150. In the envelope 1100, for example, the plurality of cold cathode fluorescent lamps 1 of the first embodiment are arranged in parallel, and light from the cold cathode fluorescent lamps 1 is diffused through the opening 1160 of the envelope 1100. Released toward 1200.

  A pair of sockets 1600 are arranged on the reflecting plate 1110 at positions corresponding to the mounting positions of the cold cathode fluorescent lamps 1. Each socket 1600 is formed by bending a plate made of a copper alloy such as phosphor bronze or aluminum, for example, and a pair of holding pieces 1610 and 1620 and a connection for connecting the holding pieces 1610 and 1620 at a lower end edge. It consists of a piece 1630. The sandwiching pieces 1610 and 1620 are provided with recesses that match the outer shape of the cold cathode fluorescent lamp 1, and when the cold cathode fluorescent lamp 1 is fitted into the recesses, the leaf springs of the sandwiching pieces 1610 and 1620 act. The cold cathode fluorescent lamp 1 is held in a socket 1600, and the socket 1600 and the power feeding terminal 30 are electrically connected. Power is supplied to the cold cathode fluorescent lamp 1 attached to the backlight unit 1000 from a lighting circuit (not shown) of the backlight unit 1000 via a socket 1600.

  The diffusion plate 1200 is a plate made of polycarbonate (PC) resin, and is disposed so as to close the opening 1160 of the envelope 1100. The diffusion sheet 1300 is made of a polycarbonate resin, and the lens sheet 1400 is made of an acrylic resin, and is arranged so as to be sequentially superimposed on the diffusion plate 1200.

  Although the backlight unit according to the present invention has been specifically described above based on the embodiments, the backlight unit according to the present invention is not limited to the above embodiments. For example, the present invention is not limited to a direct-type backlight unit, but an edge light system (also referred to as a satellite system or a light guide plate system) in which a light guide plate is disposed on the back surface of a liquid crystal panel and a cold cathode fluorescent lamp 1 is disposed on an end surface of the light guide plate. ) Backlight unit.

(Description of liquid crystal display device)
FIG. 22 is a partially broken perspective view showing a liquid crystal display device according to one embodiment of the present invention. As shown in FIG. 22, a liquid crystal display device 2000 according to an embodiment of the present invention is, for example, a 32-inch liquid crystal television, and a liquid crystal screen unit 2100 including a liquid crystal panel and the like disposed on the back of the liquid crystal screen unit 2100. The backlight unit 1000 and the lighting circuit 2200 are provided.

  The liquid crystal screen unit 2100 is a well-known one and includes, for example, a color filter substrate, a liquid crystal, a TFT substrate, a drive module (not shown), and forms a color image based on an image signal from the outside.

  The lighting circuit 2200 lights the cold cathode discharge lamp 1 inside the backlight unit 1000.

  The liquid crystal display device according to the present invention has been specifically described above based on the embodiments. However, the liquid crystal display device according to the present invention is not limited to the above embodiments.

  The cold cathode discharge lamp, the backlight unit, and the liquid crystal display device according to the present invention can be used in the entire illumination field.

The partially broken perspective view which shows the cold cathode fluorescent lamp concerning one Embodiment of this invention A perspective view showing one end of the cold cathode fluorescent lamp Expanded sectional view showing one end of the cold cathode fluorescent lamp The expanded sectional view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 1 The expanded sectional view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 2 The expanded sectional view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 3 The expanded sectional view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 4 The expanded sectional view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 5 Enlarged sectional view showing one end of a cold cathode fluorescent lamp according to Modification 6 The perspective view which shows the electric power feeding terminal in the cold cathode fluorescent lamp which concerns on the modification 7. The perspective view which shows the electric power feeding terminal in the cold cathode fluorescent lamp which concerns on the modification 8. Enlarged sectional view showing one end of a cold cathode fluorescent lamp according to Modification 9 An expanded sectional view showing one end of a cold cathode fluorescent lamp according to Modification 10 An expanded sectional view showing one end of a cold cathode fluorescent lamp according to Modification 11 The perspective view which shows the electric power feeding terminal of the cold cathode fluorescent lamp which concerns on the modification 12. An expanded sectional view showing one end of a cold cathode fluorescent lamp according to Modification 13 The perspective view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 14 The perspective view which shows the one end part of the cold cathode fluorescent lamp which concerns on the modification 15 An enlarged sectional view showing a power supply terminal of a cold cathode fluorescent lamp according to Modification 16 1 is an exploded perspective view showing a schematic configuration of a backlight unit and the like according to an embodiment of the present invention. The figure explaining the attachment state of a cold cathode fluorescent lamp The partially broken perspective view which shows the liquid crystal display device concerning one Embodiment of this invention Enlarged sectional view showing one end of a cold cathode discharge lamp with a feeding terminal according to a conventional example Expanded sectional view showing one end portion of another cold cathode discharge lamp with a feeding terminal according to a conventional example

DESCRIPTION OF SYMBOLS 1 Cold cathode fluorescent lamp 10 Glass bulb 20 Hollow electrode 22 Lead wire 30 Feeding terminal 31 Tubular body

Claims (43)

Electrodes are provided inside both ends of the glass bulb, and both ends are sealed and formed by thermal processing larger than the outer diameter of the central portion of the glass bulb. Leads of the electrodes are formed on the outer peripheral surfaces of both ends of the glass bulb. A discharge lamp having a power supply terminal connected to a wire, wherein the power supply terminal abuts and surrounds an outer peripheral surface of the glass bulb excluding both end portions larger than an outer diameter of a central portion of the glass bulb. A discharge lamp comprising an electrically conductive cylindrical body provided. The discharge lamp according to claim 1, wherein the electrode is a hollow electrode, and an inner surface of the cylindrical body is in close contact with an outer peripheral surface of a glass bulb facing the hollow electrode. The discharge lamp according to claim 1 or 2, wherein the cylindrical body has a slit portion in an axial direction thereof and has a substantially C-shaped cross section. The cylindrical body is provided with a pair of engaging portions that engage with each other across the slit portion at a part of each of a pair of end edges facing each other with the slit portion interposed therebetween. 3. The discharge lamp according to 3. The pair of engaging portions of the cylindrical body are formed by forming a concave portion at one end edge of the slit portion and a convex portion at the other end edge, respectively. Discharge lamp. The discharge lamp according to any one of claims 1 to 5, wherein a plurality of convex portions are formed on an outer peripheral surface of the cylindrical body. The plurality of convex portions on the outer peripheral surface of the cylindrical body are formed in a circumferential direction, an axial direction, or a spiral direction with respect to the axial center of the cylindrical body. Discharge lamp. 8. The cylindrical body according to claim 1, wherein at least an inner surface of an end portion opposite to the axial lead wire side is chamfered or formed in a trumpet shape. Discharge lamp. The cylindrical body includes a first cylindrical portion and a second cylindrical portion extending in the axial direction from at least one end portion of the first cylindrical portion, and the second cylindrical portion is the first cylindrical portion. The discharge lamp according to any one of claims 1 to 8, wherein an outer diameter is larger than that of the cylindrical portion. The said cylindrical body has the elastic tongue piece provided with two or more along the circumferential direction, and has clamped the outer peripheral surface of the said glass bulb | bulb with this some elastic tongue piece. Item 10. The discharge lamp according to Item 9. The said cylindrical body has a clamping member which protrudes in the radial direction inner surface, presses the outer peripheral surface of the said glass bulb, and clamps the said glass bulb. The discharge lamp according to claim 9. 12. The discharge lamp according to claim 11, wherein the clamping member is formed by bending a part of the cylindrical body and pressing a part of the bending on the outer peripheral surface of the glass bulb. The said clamping member is a some strip | belt-shaped body formed by bending from the said one end side to the said glass bulb side while extending from the one end side of the said cylindrical body. 12. The discharge lamp according to 12. The discharge lamp according to claim 1, wherein the cylindrical body is formed of a metal material wound in a spiral shape. The discharge lamp according to claim 14, wherein the cylindrical body is formed of a linear or belt-like elastic material in close contact with the cylindrical body in the axial direction. The power supply terminal includes a connecting portion that extends from the cylindrical body toward a lead body side in a cylindrical body axial direction and is connected to a part of the lead wire. The discharge lamp according to claim 15. The feeding terminal is a belt-shaped lead-out portion that extends outward from one end of the cylindrical body in the axial direction of the cylindrical body, wherein the cylindrical body is extrapolated to the outer periphery of the end of the glass bulb; The discharge lamp according to any one of claims 1 to 15, further comprising a connection portion provided at a leading end portion of the lead-out portion and connected to a part of the lead wire. The discharge lamp according to claim 16 or 17, wherein the connection portion has a U-shaped portion so as to approach a part of the outer peripheral surface of the lead wire. 18. The discharge lamp according to claim 16, wherein the connecting portion is formed with a cylindrical portion so as to approach and surround a part of the outer peripheral surface of the lead wire. The connection portion has a connection surface in which a through hole or a notch is formed, and a portion ahead of the leading end of the lead-out portion is bent so that the lead wire is inserted into the through hole or the notch. The discharge lamp according to claim 16 or 17, wherein the discharge lamp is formed. 21. The discharge lamp according to claim 18, wherein the connection portion is connected to the lead wire by caulking. 18. The connection portion is formed by bending from the leading end of the lead-out portion so as to sandwich a part of the outer peripheral surface of the lead wire. The discharge lamp described in. The connecting portion has a pair of clamping pieces that clamp the outer peripheral surface of the lead wire, and each pressing force of the pair of clamping pieces is at least 100 g or more with respect to the lead wire, The discharge lamp according to claim 22, wherein the discharge lamp is connected. The connection portion is formed by bending a portion ahead of the extending tip of the lead-out portion so as to come into surface contact with one end surface of the lead wire. 18. A discharge lamp according to item 17. 18. The connecting portion is formed by bending a portion ahead of the leading end of the lead-out portion so as to contact a part of the outer peripheral surface of the lead wire. The discharge lamp described in. The discharge lamp according to any one of claims 18 to 25, wherein the connection portion is connected to a part of the outer surface of the lead wire by welding or a soft metal. The lead wire has a pooled portion having a larger outer diameter than a portion sealed to the glass bulb at a portion joined to the power supply terminal, and at least a part of the pooled portion is made of nickel material, iron 27. The discharge lamp according to claim 1, wherein the discharge lamp is made of a material or nickel plating. The lead wire is made of a nickel material, an iron material, or nickel plating, and an external lead wire to which the feeding terminal is connected and an internal lead wire made of a material different from the external lead wire and joined to the hollow electrode. The discharge lamp according to any one of claims 1 to 26, wherein the joining portion has a pooled portion having an outer diameter larger than that of the lead wire. The said pool part is embedded in the end part of the said glass bulb | bulb closely with the bottom face, or the bottom face closely, and having a clearance in the radial direction of the lead wire. Item 29. The discharge lamp according to item 27 or 28. The discharge lamp according to claim 27 or 28, wherein the pool portion is provided with a gap from an end portion of the glass bulb. The discharge lamp according to claim 30, wherein the gap is 0.1 mm to 0.5 mm. The puddle portion has a circular cross section perpendicular to the axis of the lead wire, and the maximum diameter is larger than the maximum outer diameter of the lead wire and smaller than the maximum outer diameter of the glass bulb. The discharge lamp according to any one of claims 27 to 31. The discharge lamp according to any one of claims 28 to 32, wherein the lead wire has an external lead smaller than a heat transfer coefficient of the internal lead. The discharge lamp according to any one of claims 27 to 33, wherein the lead wire has a diameter smaller than that of the inner lead wire. The discharge lamp according to any one of claims 1 to 34, wherein a surface roughness of at least a portion of the lead wire sealed to the glass bulb is 0.2 Ra to 0.8 Ra. . One end of the lead wire is fixed to the hollow electrode by welding, the surface of the one end is 0.2 Ra to 0.8 Ra, and the chamfer dimension is 0.08 mm to 0.15 mm in the radial direction. 36. The discharge lamp according to claim 35, wherein an axial length is 0.1 mm to 0.25 mm. The discharge lamp according to any one of claims 28 to 36, wherein a part of the connection portion is brought into contact with a pooled portion of the lead wire. The discharge lamp according to any one of claims 1 to 37, wherein the connection portion has a heat transfer coefficient larger than that of the lead wire. Said connection unit is a heat transfer coefficient 75W / (m · K) ~435W / (m · K), and the conductivity is ^{9 × 10 6 S / m~65 ×} 10 6 S / m 40. A discharge lamp according to claim 38. 40. The discharge lamp according to claim 1, wherein the glass bulb is made of a glass material having a sodium oxide content of 3 wt% to 20 wt%. . 40. The discharge lamp according to claim 1, wherein the glass bulb is made of a glass material having a sodium oxide content of 5 wt% to 20 wt%. . 42. A backlight unit comprising the discharge lamp according to any one of claims 1 to 41 as a light source. A liquid crystal display panel and a backlight unit according to claim 42, wherein the backlight unit has an envelope that houses a plurality of discharge lamps according to any one of claims 1 to 40, A liquid crystal display device, wherein the envelope is disposed on a back surface of the liquid crystal display panel.

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