JPH06111793A - Double structure bulb - Google Patents

Abstract

PURPOSE:To provide a double structured bulb in which the outer tube is prevented from slipping off from a fit groove using a simple construction. CONSTITUTION:One end of an inner tube 1 consisting of an incandescent lamp or a discharge tube is fixed to a holder 20 made of an insulative substance, and the inner tube is covered with an outer tube 10, and the open end 11 of this outer tube is fitted in a fit groove 26 provided in the holder and is jointed fast by an adhesive 15, and a base 30 is mounted on the holder. In this double structural tube, the wall thickness of the outer tube open end is made greater than that of the other portions. This causes the open end to hitch at the adhesive within the fit groove to accomplish preclusion of slipping off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-tube type tube having a double-tube structure in which an inner tube such as a single-sealed halogen bulb or a single-sealed metal halide discharge lamp is housed in an outer tube. Regarding the sphere.

[0002]

2. Description of the Related Art For example, a single-sealed halogen light bulb has a cylindrical (T-shaped) bulb made of quartz glass, and a crushed seal portion formed at one end thereof. Foil conductors are sealed, internal lead wires are connected to these metal foil conductors, and a filament made of a tungsten coil is installed between both ends of the internal lead wires inside the bulb. As the filament, for example, a C-shaped filament is adopted, and a halogen gas is enclosed in this bulb.

By the way, such a halogen light bulb tends to have a higher gas pressure in the bulb and a higher bulb temperature during lighting as compared with a general incandescent bulb, so that thermal distortion is likely to occur. Therefore, there is a concern that, when the lamp is used while being naked, it may be damaged even if it receives a slight external force. Then, if the valve should be damaged, fragments may be scattered.

For this reason, this type of halogen bulb is housed in the outer tube to have a double tube structure. With such a double pipe structure, even if the inner pipe should be damaged, the outer pipe prevents scattering of fragments, and the outer pipe serves as a protective cover, so that the safety is enhanced.

By the way, in the case of such a double pipe structure,
In order to support the inner tube inside the outer tube, the crushed seal part of the inner tube is joined and fixed to a cylindrical holder made of an insulator such as heat-resistant synthetic resin or ceramics, and the open end of the outer tube is attached to this holder. The outer pipe and the inner pipe are assembled to each other through a holder by such a joint structure. An E-shaped mouthpiece is covered and attached to such a holder. In such a structure, the insulative holder constitutes the mount stem of the inner tube, which simplifies the construction of the halogen bulb having the double tube structure.

By the way, when the outer pipe is airtightly joined to the holder, a circumferentially continuous fitting groove is formed on the end face of the holder, and the opening end of the outer pipe is fitted into the fitting groove. A structure is adopted in which the joint groove is filled with an adhesive such as silicon, and the outer tube is airtightly joined to the holder with the adhesive.

[0007]

However, in the conventional case, the open end of the outer tube has a wall thickness equivalent to that of the other portion and extends straight, and the outer tube is formed of hard glass or the like. Therefore, the frictional resistance with the adhesive is small, and therefore, there is a problem that the outer tube is easy to slip out from the fitting groove because there is little catching.

The present invention has been made in view of the above circumstances. An object of the present invention is to prevent the outer tube from coming out of the fitting groove of the holder with a simple structure. It is an attempt to provide a sphere.

[0009]

The first feature of the present invention is that the wall thickness of the open end of the outer tube is made larger than the wall thickness of other portions. The second aspect of the present invention is characterized in that the outer tube is formed so that the open end of the outer tube faces outward.

[0010]

According to the present invention, both the first and second
The open end of the outer tube can be caught by the adhesive in the fitting groove, and can be prevented from coming out.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in FIGS. The drawing shows a double-tube type halogen bulb, in which 1 is a halogen bulb which is an inner tube, and 10 is an outer tube which covers this inner tube 1.

First, the inner tube 1 will be described. This inner tube (halogen bulb) 1 has a cylindrical (T-shaped) bulb 2 made of quartz glass, and one end of the bulb 2 has a crush seal portion 3. Are formed. A pair of metal foil conductors 4 and 4 made of molybdenum or the like are sealed in the sealing portion 3.
Internal lead wires 5 and 5 are connected to the metal foil conductors 4 and 4. These internal lead wires 5 and 5 are guided into the bulb 2, and a filament 6 made of a tungsten coil is installed between both ends of these. Filament 6 is
The coil axis is arranged so that it is located above the valve axis, i.e. a C-shaped filament is employed. External lead wires 7, 7 are connected to the pair of metal foil conductors 4, 4 sealed in the sealing portion 3. The bulb 2 is filled with a halogen gas.

Such an inner tube 1 is fixed to a cylindrical holder 20. The cylindrical holder 20 is made of an insulating material such as heat-resistant synthetic resin or ceramics, and has a flange portion 21 formed at an intermediate portion. A holding cylinder portion 22 is formed at one end of the flange portion 21 and a screw is provided at the other end side. Tubular part 23
Has been formed. Further, the cylindrical holder 20 has a through hole 24 formed in the center thereof. A rectangular fixing hole 25 into which the crushing sealing portion 3 of the inner pipe 1 is fitted is formed in the holding cylinder portion 22 on the one end side, and the crushing sealing portion 3 is fitted into the fixing hole 25, It is designed to be joined by an adhesive (not shown) so that the inner tube 1 can be attached to the holder 20.
It is designed to be fixed to.

The screw cylinder portion 23 formed on the other end side of the holder 20 is covered with a cap 30. Base 30 is E2
It is a 6-type mouthpiece, and the mouthpiece shell portion 31 is screwed into the threaded cylinder portion 23 of the holder 20 and is airtightly joined by an adhesive (not shown). An eyelet terminal 33, which serves as an external terminal, is attached to the base shell portion 31 via a cement 32.

Of the pair of external lead wires 7, 7 led out from the crushing seal portion 3 of the inner tube 1, one external lead wire 7 is a through hole 24 formed in the central portion of the cylindrical holder 20. From the base 30 to the eyelet terminal 33 of the base 30 and soldered to the eyelet terminal 33. The other external lead wire 7 is guided to the opening of the mouthpiece shell 31 through an insertion hole 27 formed in the side wall of the cylindrical holder 20 and soldered to the mouthpiece shell 31.

A fitting groove 26 is formed on the end surface of the flange portion 21 of the tubular holder 20 so as to surround the holding tubular portion 22. As shown in FIG. 4, the fitting groove 26 has a groove depth w of 1.5 times or more of the groove width w (d ≧
1.5w). The fitting groove 25 is formed continuously in the circumferential direction, and the open end 11 of the outer tube 10 is fitted therein.

The outer tube 10 is made of hard glass and is open at one end. The open end 11 is fitted in the fitting groove 26. In this case, the open end 11 of the outer tube 10
Are formed thicker than the other portions. That is, the opening end portion 11 is formed to have a large thickness toward the outside, and the thickness T is formed to be larger than the thickness t of other portions. further,
The open end portion 11 is formed into a curved surface whose corners have a predetermined curvature, that is, an R surface.

After inserting the opening end 11 of the outer tube 10 into the fitting groove 26, the fitting groove 26 is filled with an elastic adhesive 15 made of silicon or the like. The open end 11 of the outer tube 10 is attached to the holder 20.
Is airtightly joined to. Therefore, the inner pipe 1 is the outer pipe 10
It is covered with a double tube structure. The outer tube 10
The inside is said to be atmospheric.

In the double-tube halogen light bulb having such a structure, the inner tube 1 made of a halogen light bulb is housed in the outer tube 10 to form a double-tube structure. The tube 10 prevents scattering of debris and acts as a protective cover.

In the case of this embodiment, the open end 11 of the outer tube 10 is thicker (T> t) than the other portions,
The thick-walled open end 11 is caught by the adhesive 15 filled in the fitting groove 26, which prevents the outer tube 10 from coming out. In addition, since the joint area between the open end 11 and the adhesive 15 increases, the joint strength increases. For this reason,
The outer tube 10 is prevented from coming off and tilting.

The depth D of the fitting groove 26 is made larger than the groove width w, for example, 1.5 times or more.
The adhesive 15 filled in is deeply buried, the contact area between these is increased and the bonding strength is increased, and even if a lateral load is applied to the outer tube 10, the outer tube 10 does not tilt with respect to the holder 20. Further, since the corner portion of the opening end 11 of the outer tube 10 is the R surface, stress is not concentrated on the corner portion, and damage is prevented.

Further, when an elastic adhesive is used as the adhesive 15, even if the outer tube 10 repeats thermal expansion and contraction due to blinking, the elasticity of the adhesive absorbs the stress,
It is possible to prevent the outer tube 10 from being damaged or coming off.

In the above embodiment, the open end 1 of the outer tube 10 is
Although 1 has a thick shape toward the outside, the same effect can be obtained by making the open end 11a of the outer tube 10 toward the inside to have a thick shape as in the second embodiment shown in FIG. Further, such thick portions 11 and 11a can be formed by heating and melting the open ends to form a meat reservoir, and can be easily obtained.

Further, in each of the above-mentioned embodiments, the open end of the outer tube 10 has the thick wall structure 11 and 11a. The opening 11b may be expanded and formed, and such a skirt-shaped expanded portion may be fitted into the fitting groove 26 and joined by the adhesive 15. Even in this case, the spread-formed open end 11b is caught by the adhesive 15 to prevent the outer tube 10 from coming out, and when the outer tube 10 is thermally expanded, the open end 11b is extended and the elastic adhesive is applied. When the extension is absorbed by 15 and cannot be completely absorbed by the adhesive 15, the outer tube 10 extends relatively to the holder 20 to absorb the expansion.

In the above embodiment, the case where the one-side sealed halogen bulb is used as the inner tube 1 has been described, but the present invention is not limited to this, and the one-side sealed metal halide lamp is used as the inner tube. It is also possible to use a discharge tube such as the one described above.

[0026]

As described above, according to the present invention, the open end of the outer tube is made thicker than the other part or expanded outward, so that the open end is bonded in the fitting groove of the holder. The area in contact with the agent is increased, the adhesive strength is increased, and the thick portion and the expanded diameter portion are caught by the adhesive, so that the adhesive is prevented from coming off. Moreover, this has the advantage that it can be realized with a simple structure in which the open end of the outer tube is processed.

[Brief description of drawings]

FIG. 1 is a front view of a double tube halogen light bulb showing a first embodiment of the present invention.

FIG. 2 is a plan view showing a holder of the embodiment.

FIG. 3 is a view showing a main part of an assembly portion of an inner pipe and an outer pipe of the embodiment.

FIG. 4 is an enlarged view showing a portion where the outer tube of the embodiment is joined to a fitting groove.

FIG. 5 is an enlarged view showing a portion in which an outer pipe according to a second embodiment of the present invention is joined to a fitting groove.

FIG. 6 is an enlarged view showing a portion where an outer pipe according to a third embodiment of the present invention is joined to a fitting groove.

[Explanation of symbols]

1 ... Inner tube (halogen bulb) 2 ... Bulb
3 ... Crushing sealing part 6 ... Filament 7, 7 ... External lead wire 10 ... Outer tube 11, 11b, 11c ...
Open end 15 ... Adhesive 20 ... Cylindrical holder 22 ... Holding cylinder 2
6 ... Fitting groove 30 ... Base.

Claims (4)

[Claims] 1. A fitting in which one end of an inner tube made of an incandescent lamp or a discharge tube is fixed to a holder made of an insulator, the inner tube is covered with an outer tube, and the open end of the outer tube is formed in the holder. In a double-tube type bulb in which the opening end is fitted into the groove, the opening end is joined to the fitting groove with an adhesive, and the mouthpiece is attached to the holder. A double-tube shaped tube characterized by being made thicker than the wall thickness of. 2. The double-tube type bulb according to claim 1, wherein the corner of the open end of the outer tube is formed into a curved surface. 3. A fitting in which one end of an inner tube made of an incandescent lamp or a discharge tube is fixed to a holder made of an insulator, the inner tube is covered with an outer tube, and the open end of the outer tube is formed in the holder. In a double-tube bulb fitted in a groove, the opening end of which was joined to the fitting groove with an adhesive, and the holder was fitted with a mouthpiece, the opening end of the outer tube was bent outward. A double-tube-shaped bulb characterized in that 4. The double-tube shaped bulb according to claim 1, wherein the fitting groove has a groove depth greater than a groove width.