JPH03101047A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To reduce the stress generated in a fusion connection section or a bent section and prevent breakage by connecting end sections on the opposite side to the end sections communicated to each other on adjacent linear sections with a connecting member. CONSTITUTION:Two linear bulbs 2 and 2 are melted to each other near their tip sections and integrally connected at a fusion connection section 3. When a fluorescent lamp is lighted, a light emitting tube 1 is heated, the temperature at the inside where bulbs 2 and 2 are faced each other is made higher then the temperature at the outside, and end sections sealing electrodes tend to be separated from each other. Their base end sides are connected to each other with a silicone adhesive 20 to prevent end sections from being separated. Part of the stress generated in the fusion connection section 3 is borne by the silicone adhesive 20, and the stress generated in the fusion connection section 3 is reduced. The occurrence of cracks in the fusion connection section 3 and a bent section is prevented, and breakage is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a fluorescent lamp in which a plurality of straight portions are arranged in parallel to form one curved discharge path as a whole.

(Prior Art) Recently, fluorescent lamps have been made more compact, and for this reason, arc tubes are formed into bent shapes such as H-shapes, U-shapes, and W-shapes.

For example, in the case of an H-shaped fluorescent lamp, two straight bulbs are welded together near their tips, and the interiors of the bulbs are electrically connected to each other by the fused joint, so that they are continuous in a substantially U-shape. It consists of an arc tube with a discharge path.

The linear bulb has an electrode attached to its end and a phosphor coating formed on its inner surface.

In such an arc tube, the ends of the pair of linear bulbs provided with the electrodes are attached to the cap.

(Problems to be Solved by the Invention) By the way, conventional H-shaped fluorescent lamps of this type are mainly small in size with the aim of being compact, and have an output of about 36 W at most.

However, recently, higher output has been attempted, and 55W
Type and 96W type H-shaped fluorescent lamps are being developed.

In such high-power lamps, the distance between the electrodes is 1100 mm.
0a or more, and the total length of the arc tube reaches 30 cm or more, which causes the following problems.

That is, when the H-shaped fluorescent lamp is turned on, the arc tube generates heat, and the temperature on the opposing inner sides of the pair of bulbs becomes higher than the temperature on the outside.

In other words, heat radiation is relatively smooth on the outer surfaces of the bulbs, but the inner surfaces facing each other receive radiant heat from the opposing bulbs, and air convection is smooth in the gaps between adjacent bulbs. Because this is unlikely to occur, the temperature of these inner surfaces is higher than the temperature of the outer surfaces.

For example, when a 55W type H-shaped fluorescent lamp is lit in a horizontal position at an ambient temperature of 25°C, the temperature inside the bulb is 90°C and the temperature outside is 70°C.
It has been confirmed that the ends are 3 to 5 cm wider than when the lamp is not lit.

Further, in the fused joint that connects two linear valves to each other, the temperature of the surface facing the inner side between adjacent valves is higher than the temperature of the other circumferential surfaces.

Furthermore, since this fused joint is fused before applying the phosphor coating, the inner wall is thicker than the outer wall.
When heated, the inside expands greatly.

As a result, the arc tube is thermally deformed so that the end portions where the electrodes are sealed are bent away from each other and try to spread out from each other.

Also, when the lamp is turned off, the arc tube cools down, so
Transforms back to its original state.

Such thermal deformation generates stress in the fused joint, which may cause cracks and damage to the fused joint.

The present invention aims to provide a fluorescent lamp that can reduce the stress generated in the fused joints and bent parts and prevent damage.

[Structure of the Invention (Means for Solving the Problem) The present invention is characterized in that the mutually communicating ends and the opposite ends of adjacent straight portions are joined to each other by a joining member.

(Function) According to the present invention, since the ends of the straight parts that tend to separate from each other due to heat generation are joined by the joining member, spreading is restricted and part of the stress generated in the fused joints and bent parts is borne. Therefore, damage to the fused joints and bent parts can be prevented.

(Example) The present invention will be described below based on a first example shown in FIGS. 1 and 2.

In the figure, reference numeral 1 denotes an arc tube, which consists of two linear bulbs 2.2 welded to each other near their tips and joined together by a welded joint 3. For this reason, the two straight bulbs 2.2 are internally electrically connected to each other through the fused connection portion 3, and constitute a substantially U-shaped continuous discharge path.

In the case of a high-output fluorescent lamp of 55W type or more, the distance between the electrodes is 1000 mm or more, and the total length of the arc tube is 30 am or more.

At the end of the linear valve 2.2, as shown in FIG.
Each stem 4.4 is sealed, and an electrode 5.5 is attached to these stems 4.4.

Note that a phosphor coating 6 is formed on the inner surface of the arc tube 1,
In addition, a predetermined amount of mercury and a starting rare gas are sealed in the arc tube 1.

Such an arc tube 1 is attached to a base 10.

The cap 10 is constructed by joining a base 11 and a cap 12 each made of an insulator such as a synthetic resin.
1 has a cap pin 13 protruding from it. Although detailed explanation will be omitted, lead wires 7 connected to the electrodes 5.5 are connected to these cap pins 13.

The two linear bulbs 2.2 constituting the arc tube 1 are:
The end of the sealed electrode 5.5 is inserted into the insertion hole 15.15 formed in the base cap 12, and this insertion end is fixed to the base cap by an adhesive 14 such as silicone filled inside the base cap 12. 12.

As a result, the arc tube 1 is integrally fixed to the base 10.

In the case of this embodiment, the two linear valves 2.
2 opposite to the fused joint 3, that is, the electrode 5.
Silicone adhesive 2 as a joint part of the sealed end of 5
It is connected at 0. This silicone adhesive 20 adheres to the opposing surfaces of the proximal ends of these bulbs 2.2, and interconnects the bulbs 2.2.

The operation of the embodiment with such a configuration will be explained.

When the fluorescent lamp is turned on, the arc tube 1 generates heat, and the temperature on the opposing inner sides of the bulb 2.2 becomes higher than the temperature on the outside.

Also, in the fused joint 3 that connects the two linear valves 2.2 to each other, the temperature of the surface facing the inside between adjacent valves is higher than the temperature of the other circumferential surfaces.

Furthermore, since the inner wall of the fusion joint 3 is made thicker than the outer wall during processing, the inner wall expands significantly when heated.

As a result, the ends of the arc tube 1 with the electrodes 5.5 sealed therein are warped away from each other, causing thermal deformation in which they tend to spread out from each other, as shown by imaginary lines m in FIG.

In this embodiment, the ends of the two linear valves 2.2 opposite to the fusion joint 3, that is, the proximal ends, are joined to each other by the silicone adhesive 20. The silicone adhesive 20 prevents them from separating from each other.

Therefore, the silicone adhesive 20 bears a part of the stress that would otherwise occur in the fusion connection part 3, thereby reducing the stress that would occur in the fusion connection part 3.

Furthermore, when the lamp is turned off, the arc tube 1 cools down, so the proximal end of the linear bulb 2.2 returns to its original state and deforms, thereby reducing the distance.

In this case, the silicone adhesive 20 interposed between the proximal ends acts as a resistance, preventing extreme deformation and reducing the stress generated in the fusion joint 3 in this case as well.

Since the silicone adhesive 20 is elastically deformable, it does not completely prevent expansion and contraction at the proximal end of the linear bulb 2.2, but bears the stress while allowing some thermal deformation.

Note that a silicone adhesive 2 is used to join the arc tube 1 to the base 10.
0 also has a similar effect, so it bears the stress generated in the fusion joint 3 in cooperation with the silicone adhesive 20 interposed between the proximal ends.

Therefore, with such a structure, damage to the fusion joint portion 3 can be prevented.

Note that the present invention is not limited to the above-mentioned H-shaped fluorescent lamp, and even a U-shaped fluorescent lamp, for example, can be used in exactly the same way as in the first embodiment.

Furthermore, the present invention may be an inverted W-shaped fluorescent lamp, as in the second embodiment shown in FIG.

The fluorescent lamp shown in FIG.
2.32, these are joined by interposing a silicone adhesive 20.20 between them, and even in this way, damage to the U-shaped bent portion 34.34 can be prevented.

The present invention may also be applied to a fluorescent lamp such as the third embodiment shown in FIGS. 4 to 6.

The arc tube 40 of the fluorescent lamp shown in FIGS. 4 to 6 includes four linear bulbs 41a and 41b.

Arrange 41c and 41d in a rectangular shape like four pillars,
The ends of each valve are fused to each other by connecting portions 42.42.
They are electrically connected and connected at 43.

Therefore, the ends of these four linear valves 41 are respectively inserted into insertion holes formed in the base cap 12 and bonded to the base cap 12 via a silicone adhesive (not shown).

A bulb 41a in which the electrode 5 is sealed and another bulb 41b connected to the other end of the bulb 41a through a fusion connection 42.
A silicone adhesive is applied between the proximal end and between the bulb 41d in which the other electrode 5 is sealed and the other bulb 41c connected to the other end of the bulb 41c via the fusion connection 42. 20
．． These are joined with 20 interposed therebetween.

Even with this method, there will be no breakage of the fused joints 42, 42. losses can be prevented.

Furthermore, in each of the above embodiments, a silicone adhesive 20 is used as the joining member, and an example is shown in which this silicone adhesive 20 is attached to the opposing surface of the opposing valve 2.2. bears stress when the valve 2.2 expands or becomes pinched, but the gap narrows when an originally narrow gap widens and returns to its original size due to thermal deformation, so the stress when the gap narrows is There are no restrictions on bearing the burden.

Therefore, the present invention only needs to bear the stress when the bulbs 2.2 expand, and for this reason, the bonding member of the present invention is not limited to the silicone adhesive 20, but can bind adjacent bulbs together to prevent the expansion. It may also be an elastic belt or the like to prevent this.

Further, this joining member is not necessarily limited to having elasticity, and may have a structure in which adjacent bulbs are bound together using a metal band or the like.

[Effects of the Invention] As explained above, according to the present invention, the ends of the linear parts of the arc tubes that tend to separate from each other due to heat generation are joined by the joining member, so that the spreading is regulated and the fusion connection is achieved. Since a part of the stress generated in the parts and bent parts is borne, cracks are prevented from occurring in the fused joints and bent parts, and damage is reduced.

[Brief explanation of drawings]

1 and 2 show a first embodiment of the present invention, FIG. 1 is a perspective view of a fluorescent lamp, FIG. 2 is a sectional view thereof, and FIG. 3 is a second embodiment of the present invention. FIGS. 4 to 6 show a third embodiment of the present invention, FIG. 4 is a perspective view of the fluorescent lamp, and FIGS. 5 and 6 show different positions. FIG. 1.30.40... Arc tube, 2.41... Bulb,
3.42... Fusion joint part, 5... Electrode, 10...
Base, 20... Silicone adhesive, 32... Straight end portion, 34... Bent portion.

Claims (1)

[Scope of Claims] An arc tube has a plurality of straight sections, and these straight sections are interconnected to form a single curved discharge path as a whole, and an electrode is sealed at the end of the discharge path. 1. A fluorescent lamp characterized in that mutually communicating ends and opposite ends of adjacent straight parts are joined to each other by a joining member.