JP3701692B2 - Discharge lamp - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an improvement in a connection fixing structure between a lead wire and a coil.
[0002]
[Prior art]
In the conventional structure in which a coil as a filament is fixed to a pair of lead wires introduced into a bulb of a discharge lamp, the coil is arranged so as to intersect with the axial direction of the lead wire and fixed to the lead wire by caulking or welding. It was supposed to be. In addition, an emitter as an electron emitting substance is applied in a wound coil constituting such a coil. Since such an emitter is gradually consumed by ion bombardment or electron bombardment, a necessary amount must be secured according to a required life.
[0003]
[Problems to be solved by the invention]
However, as the discharge lamp becomes more narrow, the distance between the lead wires that fix both ends of the coil is reduced accordingly, and the gap between the inner surface of the bulb and the lead wire tends to be reduced. At this time, if the conventional coil fixing structure is adopted, the wire diameter of the lead wire also becomes extremely thin, so the coil protrudes from the side of the lead wire toward the inner wall surface of the valve, and this comes into contact with the inner wall surface of the valve. It has been found by the present inventor that problems such as the possibility of cracking in the valve occur. In addition, it becomes difficult to secure a required amount of emitter as the distance between the lead wires becomes narrower. Therefore, in order to increase the coil length, the present inventor studied that the coil is bent in a substantially U shape and fixed to the lead wire, and as a result, the end of the coil is substantially aligned with the axial direction of the lead wire. The usefulness of the structure in which the direction of matching is fixed to the lead wire was found, and it was filed earlier. At this time, when a fixing structure by melting and solidification such as spot welding is used to fix the lead wire and the coil, there is a risk that the coil may come into contact with the inner wall of the valve due to the force received during the fixing or deformation caused by heat. In addition, in the case of spot welding, it has been found that the welding electrode may come into contact with the coil and the coil may be disconnected.
[0004]
An object of the present invention is to provide a discharge lamp having a structure that can be fixed to a lead wire by spot welding or the like without disconnecting a coil that is curved in a substantially U shape. Another object of the present invention is to provide a discharge lamp having a structure in which an end portion of a coil bent into a substantially U shape can be fixed to a lead wire by spot welding or the like so as not to undesirably deform. It is to provide.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a coil end portion spirally wound around a pair of lead wires introduced from the end portion of the container and formed into a substantially U-shape as a whole. Directing in a direction substantially coincident with the axial direction, sandwiching it with the concave portion of the contact plate formed in a concave shape on one side, and partially melting and solidifying the position near the lead wire base end of the plate accordingly A discharge electrode having a structure in which the end of the coil is fixed to a lead wire is adopted for a discharge lamp.
In addition, it is provided in a pair of lead wires introduced from the end of the container, and is spirally wound in a cylinder of a cylindrical member whose axial direction substantially coincides with the lead wire, and is substantially U-shaped as a whole. Discharge of a structure in which the end of the coil formed in a letter shape is inserted, the position of the tubular member near the proximal end of the lead wire is partially melted and solidified, and the end of the coil is electrically coupled to the lead wire The electrode is employed in a discharge lamp.
[0006]
[Action]
According to the above-described means, the structure in which the end of the coil is fixed in a direction substantially coinciding with the axial direction of the lead wire, the extra portion of the coil end for fixing the lead wire to the lead wire So that the end of the coil does not protrude toward the inner wall surface of the container.
Each of the contact plate and the cylindrical member acts as a protective member for preventing the electrode from directly contacting the coil such as for spot welding, and this prevents the coil from being disconnected.
The position where the base plate and the cylindrical member are melted and solidified to fix the coil is close to the lead wire proximal end in the longitudinal direction, and the coil from the melted and solidified portion to the exposed portion of the coil is applied. It is sandwiched and restrained by a plate or a cylindrical member. This restraining force corrects even if the coil is deformed by heat due to melting and solidification, and prevents the entire shape of the coil from being undesirably tilted or bent.
[0007]
【Example】
FIG. 1 representatively shows a left cross section of a discharge lamp according to an embodiment of the present invention. The right side (not shown) is the left side and the target structure. A discharge lamp 1 shown in the figure is applied to, for example, a backlight of a color liquid crystal display device, and is not particularly limited, but includes a glass container 2 having an outer diameter of 8 mm or less and a length of 500 mm or less. , A low-power consumption type small fluorescent discharge lamp with a power consumption of 10 watts or less. A phosphor (not shown) is applied to the inner surface of the container 2, and high color rendering light emission is realized by employing, for example, a known three-wavelength phosphor. The inside of the container 2 is filled with an inert gas such as argon or xenon at a pressure of about several tens of Torr to 100 Torr, and both ends of the container 2 are sealed with stems 4 that support the discharge electrodes 3, respectively.
[0008]
Although the discharge electrode 3 is not particularly limited, it is a preheating type discharge electrode, and a pair of lead wires 5 and 5 are introduced from both ends of the container 1 and wound in a spiral shape to form a substantially U-shape as a whole. The coil 6 is formed. The coil 6 functions as a filament as a filament cathode, and an emitter such as barium oxide is applied or adhered and fixed in a coil wound a plurality of times. In the present embodiment, the coil 6 is not particularly limited, but has a double coil structure having a core wire. Thus, the end portion of the coil 6 is fixed by spot welding in a state in which the end portion of the coil 6 is sandwiched by the lead wire via the contact plate 7 in a direction substantially coinciding with the axial direction of the lead wire 5.
[0009]
FIG. 2 shows a detailed example of the structure for fixing the lead wire 5 and the coil 6, and FIG. 3 shows an axial sectional view thereof. Each of the leading end portion of the lead wire 5 and the abutting plate 7 is formed in a half-circular arc shape in cross section, and the end portion of the coil 6 is sandwiched by facing the leading end portion of the lead wire 5 and the abutting plate 7. Attached. In this state, the end of the coil 6 is fixed to the lead wire 5 by partially melting and solidifying the lead wire base end of the contact plate 7 by spot welding. The end of the fixed coil 6 faces the direction substantially coinciding with the axial direction of the lead wire 5. In each figure, 8 is a portion that has been melted and solidified by spot welding.
[0010]
FIG. 4 shows another example of the fixing structure of the lead wire 5 and the coil 6. The structure shown in the figure uses a cylindrical member 10 instead of the backing plate 7. That is, the end of the coil 6 is inserted into the cylinder of the cylindrical member 10 fixed to the lead wire 5, and the lead wire proximal end of the cylindrical member is partially melted and solidified by spot welding. The coil 6 has a structure in which the end of the coil 6 is electrically coupled to the lead wire 5.
[0011]
In FIG. 1, reference numeral 9 denotes a mercury discharge structure and alloy getter which are applied or pressure-bonded to a plate of nickel or the like. The mercury releasing structure is composed of, for example, an intermetallic compound containing titanium and mercury or a decomposition product remaining after being decomposed by heat. This mercury-emitting structure is for filling the inside of the container 2 with mercury in order to cause the phosphor to emit light with a mercury resonance line. The intermetallic compound is decomposed to release mercury into the container 2. The alloy getter is mainly composed of an intermetallic compound composed of, for example, one selected from zirconium and titanium and one selected from aluminum and nickel, and is released at the same time as the pyrolysis of the mercury releasing structure. It is used for absorbing impure gas such as water vapor and oxygen, and for absorbing impure gas generated in the container 2 over time.
[0012]
According to the said Example, the following effects are obtained.
(1) Even if the distance between the lead wires 5 and 5 is narrow according to the outer diameter of the container 2, the required emitter amount is secured by adopting a substantially U-shaped coil 6 and lengthening the coil 6. can do.
(2) A large effective light emission length can be obtained as compared with the case where the coils are simply installed in a straight line in the axial direction of the container 2.
(3) Since the end portion of the coil 6 is fixed in the direction substantially coincident with the axial direction of the lead wire 5, the excess portion of the end portion of the coil 6 for fixing to the lead wire 5 is replaced with the lead wire 5. The end of the coil 6 can be prevented from projecting toward the inner wall surface of the container 2. As a result, even when the diameter of the container 2 is thin, the distance between the lead wires 5 and 5 can be made as wide as possible to ensure the amount of emitter, and the end of the coil 6 is in contact with the inner surface of the container 2. The possibility of cracks in the container 2 can also be eliminated.
(4) Each of the contact plate 7 and the cylindrical member 10 acts as a protective member for preventing the spot welding electrode from directly contacting the coil 6, thereby preventing the coil 6 from being disconnected. .
(5) A position 8 where the caulking plate 7 or the tubular member 10 is melted and solidified in order to fix the coil 6 is located near the proximal end of the lead wire in the longitudinal direction, and from the melt-solidified portion 8 to an exposed portion of the coil 6. The coil 6 up to this point is sandwiched and restrained by the contact plate 7 or the cylindrical member 10. This restraining force is such that even if the coil 6 is deformed by heat due to melting and solidification, the coil 6 is straightly corrected, and the overall shape of the coil formed in a substantially U shape is undesirably tilted or bent. Can be prevented. Therefore, the discharge electrode manufacturing process is stable, the electrode quality can be improved, the number of work steps can be reduced, and the yield of the discharge lamp can be improved.
[0013]
Although the invention made by the present inventor has been specifically described based on the embodiments, it is needless to say that the present invention is not limited thereto and can be variously modified without departing from the gist thereof. For example, the discharge electrode of the above embodiment can also be used as a non-preheated discharge electrode. The coil is not limited to a double coil structure, and may be a triple coil structure. Further, the contact plate is not limited to the half arc shape, and may be a triangle shape or a square shape, and various shapes of the tip end portion of the lead wire can be selected accordingly. Furthermore, the cylindrical member 10 is not limited to what is fixed to the peripheral surface side of the lead wire 5 as shown in FIG. Further, at this time, the tubular member 10 may be an integrally formed member formed by forming the tip of the lead wire 5.
[0014]
【The invention's effect】
According to the discharge lamp of the present invention, by adopting a structure in which the end of the coil is fixed in a direction substantially coinciding with the axial direction of the lead wire, the extra coil end for fixing to the lead wire is adopted. The end of the coil does not protrude toward the inner wall surface of the container, and the coil end contacts the inner surface of the container as in the conventional case, and the container is cracked. The possibility of entering can be completely eliminated.
Each of the contact plate and the cylindrical member acts as a protective member for preventing the welding electrode from directly contacting the coil, thereby preventing the coil from being disconnected.
Further, the position where the caulking plate or the cylindrical member is melted and solidified in order to fix the coil is located near the proximal end of the lead wire in the longitudinal direction, and the coil from the melted and solidified portion to the exposed portion of the coil is the caulking plate. Or it is pinched and restrained by the cylindrical member. This restraining force corrects the coil even if it is about to deform due to heat caused by melting and solidification, so that the overall shape of the coil formed in a substantially U shape is undesirably tilted or bent. Can be blocked.
As a result, it is possible to cope with the narrowing of the container and the accompanying narrowing of the lead wire spacing with high reliability, and to reduce the manufacturing man-hours of such a discharge lamp and to improve the quality stability and the yield. Can contribute.
[Brief description of the drawings]
FIG. 1 is a sectional view representatively showing the left half of an embodiment of a discharge lamp according to the present invention.
FIG. 2 is a perspective view showing a detailed example of a structure for fixing a lead wire and a coil.
FIG. 3 is an axial sectional view of the structure shown in FIG.
FIG. 4 is a perspective view showing another example of a structure for fixing a lead wire and a coil.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Discharge lamp 2 Container 3 Discharge electrode 5 Lead wire 6 Coil 7 Catch plate 8 Melt-solidified part 10 Cylindrical member

Claims (4)

In a discharge lamp provided with a pair of preheating type discharge electrodes inside a hermetically sealed container,
The discharge electrode has a pair of lead wires introduced from the end of the container, and a coil that is spirally wound in a double coil structure to form a substantially U-shape as a whole, and the end of the coil Is sandwiched by a contact plate in a direction substantially matching the axial direction of the lead wire, and the corresponding plate is partially melted and solidified, and the end of the coil is fixed to the lead wire. A discharge lamp characterized by comprising: In a discharge lamp provided with a pair of preheating type discharge electrodes inside a hermetically sealed container,
The discharge electrode has a pair of lead wires introduced from the end of the container, and a coil that is spirally wound in a double coil structure to form a substantially U-shape as a whole, and the end of the coil Is sandwiched between the concave portions of the contact plate formed in a concave shape with one surface facing the direction substantially coinciding with the axial direction of the lead wire, and the contact plate is at a position near the proximal end of the lead wire. A discharge lamp characterized in that it is partially melted and solidified, and the end of the coil is fixed to a lead wire. In a discharge lamp provided with a pair of preheating type discharge electrodes inside a hermetically sealed container,
The discharge electrode includes a pair of lead wires introduced from the end of the container, a cylindrical member provided on each of the lead wires, and a spiral shape wound in a double coil structure, and is substantially U-shaped as a whole. The end of the coil is inserted into the cylinder of the cylindrical member, the position of the cylindrical member near the lead wire proximal end is partially melted and solidified, A discharge lamp having an end portion electrically coupled to a lead wire. 4. The discharge lamp according to claim 1, wherein the container is a straight tube or a bent bulb having an outer diameter of 8 mm or less.

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