JP2011124181A - Electrode of discharge lamp, and discharge lamp using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode for a discharge lamp of which a pitch of a final turn portion for the multiplex coil filament is not narrowed when the multiplex coil filament is caulked to be connected to a lead wire. <P>SOLUTION: In the electrode for the electric discharge lamp, the final turning axis Z of the final turning portion 11 and the center axis X of each leg portion 12 are not arranged parallel to each other. Since the final turning axis Z of the final turning portion 11 and the center axis X of the each leg portion 12 are not arranged parallel to each other, a shape of the leg portion 12 for the multiplex coil filament 1 is not bent. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrode for a discharge lamp and a discharge lamp using the same.

  In recent years, there has been a movement to use a hot cathode fluorescent lamp with a large amount of light per lamp as a backlight of a liquid crystal television. If it is the light quantity of a hot cathode fluorescent lamp, about 5 lamps can be used as a backlight of a 32-inch class liquid crystal television. Moreover, the hot cathode fluorescent lamp generally used is also inexpensive.

  As an electrode of a general hot cathode fluorescent lamp, a coil filament on which an electron-emitting substance (emitter) is deposited (coated) is used. As the emitter, a complex oxide of barium, strontium, calcium, or the like, which is an alkaline earth metal, is generally used. While the fluorescent lamp is lit, the emitter is consumed mainly due to evaporation, and when the emitter is exhausted, the fluorescent lamp has a lifetime. Therefore, it is better to deposit more emitters in order to extend the lifetime. For this purpose and dimensional constraints, the coil filament is generally a multi-coil filament having a structure in which a tungsten wire is wound in multiple layers.

  FIG. 1 shows an example of an electrode using multiple coil filaments. The example of the electrode in FIG. 1 is shown in Patent Document 1, and the multiple coil filament is a triple coil filament. Referring to FIG. 1, the multi-coil filament 51 includes a final turn part (final turn part) 61 to which an emitter is applied and a foot part 62 to which a lead wire 52 is connected. In the example of FIG. 1, the final turn number (turn number) of the final turn part 61 is two.

  2A and 2B are diagrams showing a general method for connecting the multi-coil filament 51 shown in FIG. 1 to a lead wire (stem lead wire). In order to connect the multi-coil filament 51 shown in FIG. 1 to the lead wire, first, the lead wire 52 is applied to each of the foot portions 62 at both ends of the multi-coil filament 51 (FIG. 2 (a)). Each lead wire 52 is bent and caulked in the direction of arrow R (FIG. 2B), and each of the foot portions 62 at both ends of the multiple coil filament 51 is fixed to each lead wire 52.

JP-A-2-276148

  By the way, in the conventional electrode as shown in Patent Document 1, each lead wire (stem lead wire) 52 is connected to each of the foot portions 62 at both ends of the multi-coil filament 51 (each lead wire 52). Is bent in the direction of arrow R and caulked to fix each of the foot portions 62 at both ends of the multi-coil filament 51 to each lead wire 52), as shown in FIG. The pitch P0 of the final turn part 61 is narrowed to the pitch P1 (P1 <P0), and adjacent coils of the final turn part 61 come into contact with each other (coil touch occurs). .

  In the present invention, when the multi-coil filament is caulked and connected to the lead wire (when the lead wire is bent and caulked to fix the foot of the multi-coil filament to the lead wire), the pitch of the final turn portion of the multi-coil filament is It is an object of the present invention to provide an electrode for a discharge lamp having a structure that does not narrow and a discharge lamp using the same.

  In order to achieve the above object, an invention according to claim 1 is provided for a discharge lamp in which lead wires are connected to the respective foot portions at both ends of a multi-coil filament in which the final turn number of the final turn portion is plural. In the electrode, the final turning axis of the final turning part and the center axis of the foot are not arranged in parallel, and the final turning axis of the final turning part and the central axis of the foot are Since the multiple coil filaments are not arranged in parallel, the shape of the foot portion of the multi-coil filament is not curved.

According to a second aspect of the present invention, in the electrode for a discharge lamp according to the first aspect, the distance a between the connection positions of the lead wires at each of the foot portions at both ends of the multi-coil filament is the final turn. When the pitch of the part is P and the final turn number of the final turn part is T,
a ≧ P × T
It is characterized by satisfying the relationship.

According to a third aspect of the present invention, in the discharge lamp electrode according to the first or second aspect, each lead wire connected to each of the foot portions at both ends of the multi-coil filament is bent by a lead wire. The bending angle θ with respect to the electrode central axis at this time is the distance between the central axes of the foot portions at both ends of the multi-coil filament. Is b, and c is the distance between the lead wire bending portion and the lead wire connecting position at the foot of the multi-coil filament,
sin θ = b / (2c)
It is characterized by satisfying the relationship.

  According to a fourth aspect of the present invention, there is provided a discharge lamp using the discharge lamp electrode according to any one of the first to third aspects.

According to the first to fourth aspects of the invention, in the discharge lamp electrode in which the lead wire is connected to each of the foot portions at both ends of the multi-coil filament where the final turn number of the final turn part is plural. The final turning axis of the final turning part and the central axis of the foot are not arranged in parallel, and the final turning axis of the final turning part and the central axis of the foot are parallel. Since the shape of the foot portion of the multi-coil filament is not curved because it is not arranged, when the multi-coil filament is caulked and connected to the lead wire (the lead wire is bent and caulked, the multi-coil filament is Provided is an electrode for a discharge lamp having a structure in which the pitch of the final turns of a multi-coil filament does not narrow when a foot is fixed, and a discharge lamp using the same. Can.

It is a figure which shows an example of the electrode using a multiple coil filament. It is a figure which shows the general method of connecting the multiple coil filament shown in FIG. 1 with a lead wire. It is a figure for demonstrating the problem in the conventional electrode. It is a figure which shows the structural example of the electrode for discharge lamps of this invention. FIG. 5 is a schematic enlarged view of FIG. FIG. 5 is an enlarged view of FIG. It is a figure which shows the structural example of the discharge lamp (for example, fluorescent lamp) using the electrode (stem) of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The inventor of the present application connects a lead wire (stem lead wire) 52 to each of the foot portions 62 at both ends of the multi-coil filament 51 in the conventional electrode as shown in Patent Document 1 (each When the lead wire 52 is bent and caulked in the direction of the arrow R to fix each of the foot portions 62 at both ends of the multi-coil filament 51 to each lead wire 52), as shown in FIG. The factor that the pitch P0 of the final turning part 61 of the filament 51 is narrowed to the pitch P1 (P1 <P0) was investigated, and the present invention was completed.

  FIG. 3A is a view showing a structure of a general multi-coil filament 51 in a conventional electrode as shown in Patent Document 1, and also in the example of FIG. ) The final turn number (turn number) of 61 is 2.

  As can be seen from FIG. 3A, in the general multi-coil filament 51 in the conventional electrode, the final turning axis Z of the final turning part (final turn part) 61 and the central axis X of the foot part 62 are parallel. It is arranged to become. Here, the final turn axis Z of the final turn part (final turn part) 61 refers to a turn coil (turning coil in the state immediately before the final turn part (final turn part) 61 is produced) in a cylindrical shape. This is equivalent to the length direction of the mandrel when the final turn part (final turn part) 61 is produced around the jig (mandrel).

  In the general multi-coil filament 51 in the conventional electrode, the final turn axis Z of the final turn part (final turn part) 61 and the central axis X of the foot part 62 are arranged in parallel, thereby FIG. ), The shape of the foot portion 62 of the multi-coil filament 51 (the shape of the portion 62a of the foot portion 62 close to the final turn portion (final turn portion) 61) is curved. That is, in order to make the central axis X of the foot 62 parallel to the final turning axis Z of the final turn part (final turn part) 61, a coil is raised from the final turn part (final turn part) 61 to Since the portion 62 has to be pulled out, the shape of the portion 62a of the foot portion 62 near the final turning portion (final turn portion) 61 is curved. When the interval between each lead wire (stem lead wire) 52 connected to each of the foot portions 62 at both ends of the multi-coil filament 51 is narrow, the curved portion 62a of the foot portion 62 of the multi-coil filament 51. In this case, when the lead wire 52 is caulked, a stress w as shown in FIG. 3B is applied to the final next turning portion (final turn portion) 61. (Stress in such a direction as to bring the coils of the final turn part (final turn part) 61 close to each other), and the pitch P0 of the final turn part 61 of the multi-coil filament 51 is narrowed to the pitch P1 (P1 <P0). Therefore, the inventor of the present application has found that adjacent coils of the final turn part 61 come into contact with each other (coil touch occurs).

  The present invention has been made on the basis of the above findings by the inventor of the present application. In the present invention, the lead wire is provided on each of the foot portions at both ends of the multiple coil filament in which the final turn number of the final turn portion is plural. In the electrode for a discharge lamp (for example, a fluorescent lamp) connected to the final swivel part, the final swivel axis of the final swivel part and the central axis of the foot part are not arranged in parallel. In this case, the shape of the foot portion of the multi-coil filament is not curved because the final turn axis and the center axis of the foot portion are not arranged in parallel. The legs of the multi-coil filament are connected by being sandwiched between the lead wires in a direction perpendicular to the central axis of the legs.

  4 (a), 4 (b), and 4 (c) are diagrams showing a configuration example of an electrode for a discharge lamp according to the present invention, FIG. 4 (a) is a front view, and FIG. 4 (b) is FIG. 4A is a top view of FIG. 4A, and FIG. 4C is a side view of FIG. In the discharge lamp electrode shown in FIGS. 4A, 4B, and 4C, the multi-coil filament 1 is connected to the final turning portion (final turn portion) 11 to which the emitter is applied and the lead wire 2. It consists of the foot part 12 to be performed. In the example of FIG. 4, the final turn number (turn number) of the final turn part 11 is two. Further, a tungsten wire or the like is used for the multi-coil filament 1, and the multi-coil filament 1 is a double coil filament or a triple coil filament. As the emitter applied to the final swivel unit 11, a complex oxide of alkaline earth metals such as barium, strontium, and calcium is used.

  FIG. 5 is a schematic enlarged view of FIG. Referring to FIG. 5, the electrode for the discharge lamp leads to each of the foot portions 12 at both ends of the multi-coil filament 1 in which the final turn portion 11 has a plurality of turn turns (2 in this example). Wires 2 are connected. At this time, each foot 12 of the multi-coil filament 1 is sandwiched between the lead wires 2 in a direction perpendicular to the central axis X of each foot 12 and is caulked to be connected. It has become. That is, the extending direction Y (illustrated in FIG. 4A) of each lead wire 2 is a direction perpendicular to the central axis X of each foot 12 in FIG.

  In this discharge lamp electrode, the final turn axis Z of the final turn part 11 and the central axis X of each foot 12 are not arranged in parallel, and the final turn axis of the final turn part 11 is not. Since Z and the central axis X of each foot 12 are not arranged in parallel, the shape of the foot 12 of the multi-coil filament 1 is not curved. Here, the final turn axis Z of the final turn part 11 refers to a turn coil (turn coil in the state immediately before the final turn part (final turn part) 11) is formed as a cylindrical jig (mandrel). ) Around the mandrel and the length of the mandrel is equivalent to the length of the mandrel.

  Thus, the electrode for the discharge lamp of the present invention is not curved in the shape of the foot portion 12 of the multi-coil filament 1, so that each lead wire connected to each of the foot portions 12 at both ends of the multi-coil filament 1 is used. (Stem lead wire) Even when the interval between the two is narrow, when the lead wire 2 is caulked and connected to the foot portion 12 of the multi-coil filament 1, the final turn portion (final turn portion) 11 includes: The stress w (stress in the direction in which the coils of the final turn part (final turn part) 11 are brought close to each other) as shown in FIG. 3B does not work, and therefore the final turn part 11 of the multi-coil filament 1 is not affected. Is no longer narrowed to the pitch P1 (P1 <P0).

  By having such a feature (because the shape of the foot 12 of the multi-coil filament 1 is not curved), adjacent coils of the final swivel unit 11 are in contact with each other. (Coil touch occurs) can be eliminated, and shortening of the lamp life can be avoided. In addition, since the coil length of the final turn part 11 between the two lead wire connecting positions can be maximized, the amount of emitter filling can be increased and the life of the lamp can be extended.

More specifically, the characteristics of the electrode for a discharge lamp according to the present invention (the structure in which the shape of the foot portion 12 of the multi-coil filament 1 is not curved) are more specific in each of the foot portions 12 at both ends of the multi-coil filament 1. When the distance a between the connection positions of the lead wires 2 is P, the pitch of the final turn part 11 is P, and the final turn number of the final turn part 11 is T (2 in this example) (see FIG. 5),
a ≧ P × T
It is in satisfying the relationship.

The above characteristics of the electrode for the discharge lamp of the present invention (structure in which the shape of the foot 12 of the multi-coil filament 1 is not curved) are more specifically shown in FIG. 6 (note that FIG. 4 (c) is an enlarged view), each lead wire 2 connected to each of the foot portions 12 at both ends of the multi-coil filament 1 is opposite to each other with respect to the electrode center axis E in the lead wire bending portion 15. The bending angle θ with respect to the electrode center axis E at this time is the distance between the center axes X of the foot portions 12 at both ends of the multi-coil filament 1 as b (= P × T). And when the distance between the lead wire bending portion 15 and the lead wire connecting position in the foot portion 12 of the multi-coil filament 1 is c,
sin θ = b / (2c)
It is in satisfying the relationship.

  As described above, in the present invention, the multi-coil filament 1 may be a double coil filament or a triple coil filament (triple coil filament), but if a multi-coil filament is used for the multi-coil filament 1, a multi-coil filament is used. 1 can be securely fixed to the lead wire 2. That is, if the multi-coil filament 1 is a triple coil filament, the connection portion with the lead wire 2 is coiled, so that even if subjected to an impact or the like, this acts as a wedge. Since it becomes difficult to come off, the reliability is further improved.

  In order to reduce the diameter of the fluorescent lamp, it is desirable to reduce the distance between the lead wires 2. However, if the distance between the lead wires 2 is reduced, the final turn number (turn number) must be reduced. If the final turn number (turns) is set to 1, the amount of application of the emitter is reduced and the life is shortened. Accordingly, the application area of the emitter is wide, and in order to increase the application quantity (filling quantity) of the emitter, it is necessary to set the final number of turns (number of turns) to 2 or more. However, if the final number of turns (number of turns) is 3 or more, particularly 6 or more, the distance between the lead wires 2 increases, making it unsuitable for reducing the diameter of the fluorescent lamp. Therefore, the final number of turns (number of turns) is preferably 2 to 5, and preferably the number of final turns (number of turns) that can reduce the diameter is 2.

  FIG. 7 is a diagram showing a configuration example of a discharge lamp (for example, a fluorescent lamp) using the electrode (stem) 3 of the present invention. The example of FIG. 7 has a structure in which electrodes (stems) 3 are sealed with beads 41 at both ends of the glass tube 40 (bead stems are used). In addition to this, there is a method using a button stem or the like for sealing.

  To manufacture the fluorescent lamp of FIG. 7, the electrode 3 of the present invention in which a multi-coil filament 1 coated with an emitter is connected to a lead wire 2 at one end of a glass tube 40 coated with a phosphor on the inner wall; That is, the stem (bead stem (or button stem)) to which the bead (or button) 41 is attached is fixed (however, a gap for introducing gas and mercury is provided), and the other end of the glass tube 40 is The electrode 3 similar to the above, that is, the stem is sealed, then the emitter is activated, gas and mercury are sealed, and sealed to complete a fluorescent lamp.

  In each of the above-described examples of the present invention, as the material of the lead wire 2, when the multi-coil filament 1 is caulked, if it is too hard, the multi-coil filament 1 may be damaged, or the caulked portion may spread after the lead wire 2 is connected, Since a problem may occur, it is preferable to select a material softer than the material of the multi-coil filament 1 (such as tungsten). That is, for example, nickel, a nickel plating material, a nickel alloy, or Kovar is used for the lead wire 2.

The present invention can be used for fluorescent lamps and the like.

1 Multiple Coil Filament 2 Lead Wire 3 Electrode (Stem)
11 Final turning part 12 Foot part 40 Glass tube 41 Bead (or button)

Claims (4)

In the electrode for a discharge lamp in which the lead wire is connected to each of the foot portions at both ends of the multi-coil filament having a plurality of final turn numbers of the final turn portion, the final turn shaft and the foot of the final turn portion The central axis of the multi-coil filament is not arranged in parallel with the central axis of the multi-coil filament because the final pivot axis of the final pivot part and the central axis of the foot part are not arranged in parallel. An electrode for a discharge lamp, characterized in that the shape is not curved. 2. The electrode for a discharge lamp according to claim 1, wherein the distance a between the connection positions of the lead wires at each of the foot portions at both ends of the multi-coil filament is P as the pitch of the final swivel portion. When the final number of turn of the turning part is T,
a ≧ P × T
An electrode for a discharge lamp characterized by satisfying the following relationship: The electrode for a discharge lamp according to claim 1 or 2, wherein the lead wires connected to each of the foot portions at both ends of the multi-coil filament are opposite to each other with respect to the center axis of the electrode at the lead wire bending portion. The bending angle θ with reference to the electrode central axis at this time is defined as b. The distance between the central axes of the foot portions at both ends of the multi-coil filament is b, When the distance between the lead wire connecting position at the foot of the multi-coil filament is c,
sin θ = b / (2c)
An electrode for a discharge lamp characterized by satisfying the following relationship: A discharge lamp using the electrode for a discharge lamp according to any one of claims 1 to 3.

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