JPH1027581A - Pressure tightness envelope and its manufacture, and lamp using the envelope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the pressure tightness of an envelope further, by eliminating the inside distortion at the curved surface from the shoulder to the small diameter extension of the main body of the envelope, and prevent a bursting accident depending on the inside distortion, even when the inner pressure is increased. SOLUTION: In an envelope 1 for double end type lamp comprising an envelope main body 1H to house filaments or an electrode, and a small diameter extension 1F for sealing part forming projected at least at one side end of the envelope main body 1H, a curved surface part formed from the shoulder 1G of the envelope main body 1h to the small diameter extension 1F is composed of integrally seamless formation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-resistant envelope for a double-ended lamp used for various purposes including general household use, and which is particularly excellent in pressure resistance and manufacturing cost, and a method for manufacturing the same. The present invention relates to a lamp using an envelope.

[0002]

2. Description of the Related Art Incandescent lamps, for example, eggplant-shaped incandescent lamps called GLS, reflector-type incandescent lamps on which aluminum is deposited, shield beam-type incandescent lamps, incandescent lamps used in chandeliers, and silicon inside a glass bulb Various incandescent bulbs such as silica spheres coated with
Since Edison's invention, it has been widely used around the world.
In light of the future energy situation, the United States passed the Energy Saving Bill promptly in the United States. % Has been statutory. There is no doubt that this trend has led to legislation in Korea and will soon become a global trend. On the other hand, in the field of discharge lamps, particularly metal vapor discharge lamps (also known as metal halide lamps), demand for small and high-performance bulbs for general lighting and vehicle lighting (particularly for headlamps) is rapidly increasing. .

In order to meet such demands, low power consumption type halogen lamps and small metal halide lamps have come to the fore. That is, the halogen lamp has a high luminous efficiency, the brightness is increased by 30 to 40% with the same power consumption as compared with the eggplant type incandescent lamp for general lighting called GLS, and the life is about 2 times.
More than double. On the other hand, small metal halide lamps are also more energy-saving than halogen lamps, have good optical characteristics and excellent light condensing properties, and generally have high light use efficiency, so demand in the precision optics field is also rapidly increasing. .

[0004] However, in the former halogen lamp, it is necessary to cause a halogen cycle to occur inside the bulb.
Therefore, the inner wall temperature of the bulb must be at least 180 ° C. for bromide and 150 ° C. for chlorine compounds. Further, in order to extend the life of the halogen lamp, it is necessary to suppress the evaporation of the filament made of tungsten. Generally, a method of pressurizing the inside of the tube (usually 3 to 7 atm) is employed. Further, in the case of a metal halide lamp, by applying pressure, the evaporation of the electrodes can be suppressed, the lamp life can be prolonged, and the luminous efficiency and the color rendering can be improved. When the sealing pressure in the envelope is increased as described above, a distortion may occur in the envelope, or a rupture accident may occur if a part of the envelope has a low pressure resistance.

FIGS. 19 to 21 show a conventional manufacturing procedure of a double-end type envelope (1 ') whose both ends are narrowed to a small diameter. The large-diameter straight pipe (31') cut to a predetermined size is shown. The two ends of the tube are shrunk by heating, and the contracted end (32 ') has a small diameter straight pipe (30')
The heated and softened ends are joined to each other, and a double-end type envelope for a halogen lamp or a metal halide lamp having a small-diameter straight tube (30 ') connected to both ends as shown in FIG.
(1 ′) was formed.

In this case, the joint (1I ') of the envelope (1') is generated by the shoulder (1G ') of the envelope main body (1H') and the small diameter straight pipe.
This is the joint with (30 '). (See FIGS. 22 and 23).
This joint portion (1I ′) has a burner flame impurity during heating (for example, carbon is an impurity when the burner flame is a propane-oxygen flame, and an OH group is an impurity when a hydrogen-oxygen flame is used).
Adheres to the surface forming the joint (1I ') between the shoulder (1G') and the small-diameter straight pipe (30 '), which is caught in the glass at the time of joining, and the inside of the joint (1I') Make up the defect. In addition, when the two (1G ') and (30') are joined, the strength and strength of the joint are generated due to the degree of melting and the temperature of the glass at various places, and at the same time, the thermal distortion and the thickness variation due to the degree of softening and joining. Occurs. In addition, internal strain due to uneven distribution of material is applied to the joint (1I '), and while the lighting and extinguishing are repeated, cracks are formed in the joint (1I'), and often a filament (not shown) is formed. The arc discharge at the time of disconnection (the possibility of the double-end type is less than that of the single-end type halogen lamp is less than that of the single-end type halogen lamp) sharply increases the pressure inside the envelope (1 '), causing internal defects. Ruptured instantaneously from the junction (1I ') containing the slab or its surroundings. Therefore, sufficient pressure could not be applied to extend the life of the envelope (1 ') due to structural defects.

In addition, low power consumption type halogen lamps and small and high performance metal halide lamps, which are used especially at a commercial voltage, which are becoming popular in recent years, require extremely strict production conditions because of their small size. In particular, impurities and impurity gases generated from raw materials constituting the lamp greatly affect the performance. How to remove impurities and impurity gases is a major issue in improving the performance of the lamp, and it is necessary to avoid carbon and OH groups at the time of joining as much as possible. The shoulder (1G ') of the envelope body (1H') and the small diameter straight pipe (3
0 ′) and the junction (1I ′) contains impurities and impurity gases as described above, so that the junction (1I ′) is exposed in the envelope body (1H ′). During the operation of the lamp, impurities and impurity gases are diffused from the joint (1I ') into the envelope body (1H') during the operation of the lamp, which is a characteristic of a low power consumption type halogen lamp and a small and high performance metal halide lamp. And shortened life expectancy.

[0008]

The problem to be solved by the present invention is as follows.
In the case of the envelope, the curved portion formed from the shoulder portion of the envelope body to the small-diameter extension portion is formed by integral molding without a seam. In order to prevent defects due to internal distortion and internal defects even if the internal pressure of the envelope is increased by eliminating the defects and increasing the pressure resistance of the envelope, this envelope is used. Lamps, the joints should not be exposed inside the enclosure body so that the characteristics and life of low-power-consumption halogen lamps and compact high-performance metal halide lamps are not significantly affected. is there.

[0009]

The first aspect of the present invention relates to a seamless double-ended envelope (1) of the present invention from a shoulder (1G) to a small-diameter extension (1F). 6 ′), and a small-diameter extension for forming a sealing portion protruding from at least one end of the envelope body (1H).
(1F) and the envelope (1) for the double-ended lamp (A) formed from the shoulder (1G) of the envelope body (1H) to the small-diameter extension (1F). The curved surface portion is formed by integral molding without a seam. " According to this, the curved portion formed from the shoulder (1G) to the small-diameter extension (1F) of the envelope body (1H) for the double-end type lamp (A) has no seam, so this portion is The conventional internal distortion and internal defects do not occur, and even if high-pressure gas is sealed in the envelope (1), the shoulder (1G) may become a weak point and cause rupture as in the conventional case. Absent.

The second aspect is the double-ended lamp.
Regarding the method of manufacturing the envelope (1) for (A), refer to `` Straight pipe for forming envelope
(31) is formed into a small diameter while heating the appropriate place, and the small diameter portion (1
f) or large diameter part (1h) or small diameter part (1f) and large diameter part (1h)
Cut the right place with a combination of, a large-diameter envelope main body (1H) that stores the filament (6) or the electrode (6 ′), and is protruded from at least one end of the envelope main body (1H). And a small-diameter extension portion (1F) for forming a sealing portion.
The curved surface portion formed from the shoulder portion (1G) to the small-diameter extension portion (1F) of H) is integrally formed without a seam ”. Here, the cut portion is one or two or more portions, only the small diameter portion (1f), or the large diameter portion
Various combinations such as only (1h) or a small diameter portion (1f) and a large diameter portion (1h) are adopted according to the application. (Fig. 3 (a)
~ (E))

Claim 3 is a double-ended lamp (A).
When the auxiliary cylinder (30) is connected to the small-diameter portion (1f) in the envelope (1) for `` the envelope is formed into a small diameter while heating the appropriate place of the straight tube (31) for forming the envelope, Cut the appropriate part at the small diameter part (1f) or the large diameter part (1h) or the combination of the small diameter part (1f) and the large diameter part (1h), and connect the auxiliary cylinder (30) to the small diameter part (1f). Large-diameter envelope body (1H) that accommodates filament (6) or electrode (6 ')
And, a large-diameter portion extending from the small-diameter extension portion (1F) or the small-diameter extension portion (1F) for forming a sealing portion protruding from at least one end of the envelope body (1H) ( 1h), and the curved surface formed from the shoulder (1G) to the small-diameter extension (1F) of the envelope body (1H) is integrally formed without a seam. '' And

A fourth aspect of the present invention is a double-ended lamp (A) using the pressure-resistant envelope (1) according to the first aspect. 1H), the portion between the main body side ends of the sealing portions (13) formed at both ends is a seamless integral molding '', and according to this,
As in the conventional example, the shoulder (1G ') of the envelope body (1H') and the small diameter straight pipe
The junction (1I ′) with the (30 ′) is not exposed in the envelope main body (1H ′), and impurities and impurity gas contained in the junction (1I ′) are not exposed to the envelope main body (1H ′). It does not dissipate into the inside of '), and does not impair the characteristics and life of low-power-consumption-type halogen lamps or small-sized high-performance metal halide lamps whose production conditions are extremely severe. Here, the lamp (A) includes a halogen lamp and a metal halide lamp throughout the specification.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a method of manufacturing an envelope (1) for a double-ended lamp (A) according to the present invention will be described with reference to FIGS. As the material of the glass used for the envelope (1), for example, quartz glass, hard glass, or another material suitable for the intended use is used. The inner diameter of the large-diameter glass straight tube (31) used for the envelope (1) is generally 4 to 10 mm, and the wall thickness is 0.8 to 1.5 mm.

First, the envelope forming straight pipe (31) is rotated while being heated at an appropriate position, and a roller (R) is pressed against the heated portion, and care is taken so that the thickness of the portion does not decrease so much. The heating portion is formed to have a small diameter while being heated. Fig. 1 shows the small diameter part (1f)
In this case, the number is three, but the number is of course not limited to this, and an optimum number is selected with one or more. The small diameter portion (1f) or the large diameter portion (1h)
The length is not limited, and an optimum length that does not cause any trouble in the next step is selected.

The roller (R) is selected according to the length of the small diameter portion (1f). Generally, from the large diameter part (1h) to the small diameter part (1h)
Since it is desirable that the curvature of the shoulder (1G) that moves to f) is gentle, it is desirable to chamfer the corners of the roller (R). Depending on the purpose, the shape of the roller (R) can be shaped into any shoulder (1G), and any part of the small-diameter portion (1f) can be narrowed inward (not shown) or It goes without saying that a protrusion (not shown) can be formed, and the small-diameter portion (1f) can be formed into any irregular shape such as a tapered shape.

When the forming of the large-diameter straight pipe (31) is completed, the process proceeds to the cutting step shown in FIG.
(1) is available in various shapes.Sections of the small diameter part (1f) and the large diameter part (1h) are cut off from one end of the envelope body (1H) to connect the exhaust port and seal. Small diameter extension
(1F) protruding, and the other end of the envelope body (1H) is a forming portion (13a) of the sealing portion (13), and is a double-end opening type (FIG. 3).
(Refer to (a).), At one or more locations, only the small-diameter portion (1f) is cut, and the small-diameter extension (1F) for exhaust port connection and sealing is cut from one end of the envelope body (1H). Opening at both ends, with a small-diameter extension (1F) for forming the sealing portion (13a) projecting from the other end of the envelope body (1H) (see Fig. 3 (b)) At one or more locations, only the large diameter portion (1h) is cut and a small diameter extension (1F) protrudes from one end of the envelope body (1H), and further from the small diameter extension (1F) Large diameter section (1
h) protrudes and the small-diameter extension (1F) or the large-diameter portion (1h)
Is used for sealing, and the other end of the envelope body (1H) is a forming portion (13a) of the sealing portion (13). (1f) and the large-diameter part (1h) are cut at appropriate places, and a small-diameter extension (1F) protrudes from one end of the envelope body (1H), and further connects the exhaust port from the small-diameter extension (1F). The large-diameter portion (1h) protrudes and the small-diameter extension portion (1F) or the large-diameter portion (1h) becomes the sealing portion forming portion (13a), from the other end of the envelope body (1H). A double-end opening type in which a small-diameter extension (1F) serving as a sealing portion forming portion (13a) (or an exhaust port connection) protrudes (FIG. 3 (d)). By cutting only the diameter part (1h), a small-diameter extension (1F) protrudes from both ends of the envelope body (1H), and a large-diameter part for exhaust port connection from one of the small-diameter extensions (1F). The part (1h) protrudes, and the large diameter part extends from the other small diameter extension (1F).
(1h) is protruding, and either of the small-diameter extension portion (1F) or the large-diameter portion (1h) becomes a sealing portion forming portion (13a). See).

FIG. 8 shows a double-ended lamp (A).
It is a manufacturing method of another example of the envelope (1) for use. In this case, when the small diameter portion (1f) is heated and cut, the cut end is closed end (1f).
b). What is important in each case is that the curved surface portion that transitions from the shoulder portion (1G) of the envelope body (1H) to the small-diameter extension portion (1F) and its surroundings are formed without seams, and this portion is a conventional example. No internal defect or internal distortion due to the connection occurs. When the total length of the small-diameter extension (1F) is insufficient, an auxiliary cylinder (30) is connected to the end of the small-diameter extension (1F) as shown in FIG. The auxiliary cylinder (30) may be connected to the ends of both the small-diameter extensions (1F). (Of course, only one of them may be used.
If the total length of (1F) is sufficient, connection of the auxiliary cylinder (30) is unnecessary. Here, a case will be mainly described in which the auxiliary cylinder (30) is connected to the end of the small-diameter extension (1F). Note that the auxiliary cylinder (30) has various shapes such as a simple small diameter straight pipe or a large diameter straight pipe extending at the tip of the small diameter straight pipe. By doing so, when the small-diameter extension (1F) is sealed from the base or near the base, the connection part (1I) with the auxiliary cylinder (30) where there is internal distortion or internal defect due to connection is fused. The connection portion (1I) disappears due to attachment or pinching, and the connection portion (1I) disappears, so that problems such as various distortions, impurities, and impurity gases due to the presence of the junction portion (1I) are eliminated.

Next, the procedure for manufacturing the double-ended halogen lamp (A) will be described with reference to FIG. Both ends are open, the envelope body (1H) is thick, and both the small-diameter extensions (1F) have a small diameter. (1) << In this embodiment, the small-diameter extension (1F) Although the case where the auxiliary cylinder (30) is connected to one of them is shown, it is needless to say that the present invention is not limited to this. "Preparing FIG. 3 (b) or FIG. 5" (of course, the present invention is not limited to this; FIG. 3 (a) (c) (d) (e) and other cases), and mount (M) is mounted on one side. Insert the inside of the envelope (1) from the open end (1a), suspend it with the support member (3), and position the mount (M) in the axial and radial directions with respect to the envelope (1). Holds the envelope (1) and the mount (M) in the optimal position.

The filament (6) of the mount (M) is a double coil (or single coil) made of tungsten.
In the case of the present embodiment, a lead portion (21) in which a protection coil is covered on a single coil portion at both ends is formed, the lead portion (21) is welded to a sealing foil (10), and further the sealing is performed. For foil
(10) with external lead rod (8) welded (Fig. 11
(See Fig. 12), without the sealing foil (10), the lead part (21) is directly welded to the lead rod (8a) (see Fig. 12). For glass, the latter for hard glass. Further, the shape of the lead portion (21) is not limited to the above shape, and a single coil portion of the filament (6) may be directly welded to the end of the sealing foil (10), or a rod-shaped inner portion may be formed. It may be connected to the sealing foil (10) via a lead rod (not shown).

When the axial and radial alignment of the mount (M) and the envelope (1) is completed, the lead rod (8a) is chucked with an appropriate holder (not shown) to fix the mount (M). I do. After that, the auxiliary cylinder connected to the small-diameter extension (1F)
An inert gas such as nitrogen or argon gas is blown into the envelope (1) from the open end (1a) of (30), and the open end (1a) at the other end is blown.
To keep the inside of the envelope (1) and the blowout portion of the open end (1a) on the blowout side in an inert atmosphere.

Subsequently, a part of the small-diameter extension (1F) or the whole of the small-diameter extension (1F) corresponding to the sealing foil (10) on the blowing side of the mount (M) is heated and softened, Generally, the entirety of the sealing foil (10) is embedded in the sealing portion (13) by pinching and sealed.

When the sealing is completed, the air in the envelope (1) is evacuated to a substantially vacuum state through the auxiliary cylinder (30), and further operations such as washing are performed. A part or small-diameter extension of the small-diameter extension (1F) connected to the auxiliary cylinder (30) while cooling almost the entire vessel (1) with liquid nitrogen
The whole of (1F) is heated and softened as described above, and is generally pinched to embed and seal the entire sealing foil (10) in the sealing portion (13). Also in this case, the connection part (1I) between the auxiliary cylinder (30) and the small-diameter extension part (1F) is cut off or pinched, and the connection part (1I) is mixed and integrally formed with the sealing part (13). As a part, the weak point does not occur in the curved portion following the sealing portion (13) from the shoulder (1G) of the envelope body (1H) as in the related art. In other words, the curved surface portion is a completely integral molded portion and does not have a weak point portion as in the conventional example. The sectional views are shown in FIGS.
FIG. Traces of the connecting portion (1I) are symbolically shown by broken lines, but in reality there are almost no traces integrated.

FIG. 11 shows a case where one end is a small-diameter extension portion (1F) and the other end is a large-diameter portion (1h). The halogen lamp produced by using the envelope (1) is shown in FIG. (A) is FIG. 15. FIG. 13 shows an example in which a large-diameter portion (1h) extends integrally from one small-diameter extension (1F), and the other end is a small-diameter extension (1F). In this case, the small-diameter extension (1F) is sealed.

FIG. 14 shows an example of a sealing operation when an envelope (1) having one opening and the other end closed is used. In this case, the mount (M) is inserted into the envelope (1) from one open end (1a), and is suspended by the support member (3) as described above. The mount (M) does not use the sealing foil (10), and the material of the envelope (1) is hard glass.

Upon completion of the axial and radial alignment of the mount (M) and the envelope (1), the air in the envelope (1) is evacuated to a substantially vacuum state through the small-diameter extension (1F). Subsequently, a washing operation is performed to keep the inside of the envelope (1) in a reduced-pressure inert atmosphere.

Subsequently, a part of the closed-side small-diameter extension (1F ') is heated to soften / shrink, and if necessary, pinching is performed so as to center on the connection between the lead rod (8a) and the lead (21). The vicinity is buried in the sealing portion (13) and sealed.

When the sealing is completed, the air in the envelope (1) is evacuated to a substantially vacuum state through the small-diameter extension (1F), and a work such as a wash hang is performed.
While cooling almost the entire envelope (1) with liquid nitrogen, a part of the small-diameter extension (1F) or the entire small-diameter extension (1F) or an auxiliary cylinder
The portion including the connection portion (1I) between the (30) and the small-diameter extension portion (1F) is heated and softened and shrunk as described above, and pinched if necessary, and the lead rod (8a) and the lead portion (21) as described above. ) And the vicinity thereof is buried and sealed in the sealing portion (13). Finally, the closed end (1b) is cut off to expose the lead rod (8a). In this case, the auxiliary cylinder (30) and the small-diameter extension
The connection part (1I) with (1F) is cut off or contracted and sealed, so that the connection part (1I) becomes a part of the sealing part (13), which is mixed and unified, and the connection part (1I) Leaves almost no trace.

FIG. 18 is a sectional view of a metal halide lamp (A) using the envelope (1) of the present invention. In the figure, reference numeral (6 ') denotes an electrode, the rear end of which is welded to the sealing foil (10) embedded in the sealing portion (13).

Next, the double-end type halogen lamp
The case where (A) is mounted on the outer valve (2) and used will be described. The outer bulb (2) shown in FIG. 24 is of an eggplant type, and a neck (7) is protruded from the base thereof. The neck (7) of the outer bulb (2) has a conventional eggplant type general incandescent lamp. A screw cylinder part (5) of the same size is mounted and fixed with an adhesive. The stem (4) is integrated with the stem (4) at the opening of the neck (7), and a part of the stem-side lead rod (14) is embedded in the stem (4).
One end of the stem-side lead rod (14) protrudes from the tip of (4).

The halogen lamp (A) has external lead rods (8) (8) of the lamp (A) attached to lead rods (14) (14) derived from a stem (4) attached to a neck (7). 8) is attached integrally. In the present embodiment, one external lead rod (8) and the lead rod (14) on the stem side are connected via a relay lead rod (14a). The connection between the lead rods is generally performed by welding.

A center contact (17) disposed at the center of the screw cylinder (5) via an insulator (16) and one stem-side lead rod (14).
However, the other stem-side lead rod (14) in the screw cylinder (5)
However, they are generally connected via a Dumet wire.
As a result, it can be used by being directly attached to a conventional eggplant-type incandescent lamp socket.

[0032]

According to the present invention, since there is no seam in the curved portion formed from the shoulder portion of the envelope body to the small-diameter extension portion, no internal distortion occurs in this portion, and the pressure resistance of the envelope is reduced. Even if high-pressure gas is sealed in the envelope, the portion from the shoulder portion to the curved surface portion does not become a weak point and rupture does not occur even in the conventional case. Therefore, the internal pressure of the envelope can be made higher than before, and the life and characteristics of the halogen lamp and the metal halide lamp can be greatly improved. Further, since impurities and impurity gases at the joint portion are not diffused into the envelope body, a person who realizes a lamp with higher performance and higher quality can be realized.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a method of forming a straight tube for forming an envelope according to the present invention.

FIG. 2 is a front sectional view showing a cutting position of the molding material formed in FIG. 1;

FIGS. 3A to 3E are front sectional views of each envelope material when the molding material of FIG. 1 is cut.

FIG. 4 is a front sectional view showing a state in which an auxiliary cylinder is connected to the double-end type envelope material shown in FIG.

FIG. 5 is a front sectional view of the double-ended envelope of the present invention formed in FIG. 4;

FIG. 6 is a front sectional view showing a state in which auxiliary cylinders are connected to both ends of the double-end type envelope material shown in FIG.

FIG. 7 is a front sectional view of the double-ended envelope of the present invention formed in FIG. 6;

FIG. 8 is a front sectional view showing another cutting method of the molding material formed in FIG. 1;

FIG. 9 is a front sectional view of the double-ended envelope with one end closed formed in FIG. 8;

FIG. 10 is an enlarged partial cross-sectional view of a portion extending from the shoulder of the envelope main body of the envelope of the present invention to a small-diameter extension and a connection portion between the small-diameter straight pipe and the small-diameter extension.

11 is a front sectional view of a state in which the mount is sealed using the double-ended envelope of FIG. 5 of the present invention.

FIG. 12 is a front sectional view of a state in which a mount is sealed using a double-ended envelope according to another example of the present invention.

FIG. 13 is a front sectional view showing a state where a mount is sealed using a double-ended envelope according to still another example of the present invention.

FIG. 14 is a front sectional view of a state in which a mount is sealed using a double-end type envelope of one end open and the other end closed type according to the present invention.

FIG. 15 is a front sectional view of the lamp when the sealing of FIG. 11 is completed.

16 is a front sectional view of the lamp when the sealing of FIG. 13 is completed.

17 is a front sectional view of the lamp when the sealing of FIG. 12 is completed.

FIG. 18 is a front sectional view of a metal halide lamp using the envelope of the present invention.

FIG. 19 is a front sectional view showing a state where one end of a conventional straight tube for an envelope is heated.

20 is a front sectional view showing a state in which a small-diameter straight pipe is connected to heating portions at both ends of the straight pipe in FIG. 18;

FIG. 21 is a front sectional view of the conventional double-ended envelope formed in FIG. 19;

FIG. 22 is an enlarged front sectional view showing details of a connection portion from a shoulder of a main body of a conventional double-end type envelope to a small-diameter straight pipe.

FIG. 23 is an enlarged front sectional view showing details of another connection portion from the shoulder of the envelope main body to the small-diameter straight pipe of the conventional double-ended envelope.

FIG. 24 is a partially cutaway front view when the double-end type lamp of the present invention is mounted on an eggplant type outer bulb.

[Explanation of symbols]

(A) ... lamp (1) ... envelope (1F) ... small-diameter extension (1H) ... envelope body
(1G) ... shoulder (2) ... outer valve (3) ... locking member (4) ... stem (5) ... screw cylinder (6) ... filament (7) ... neck (10) ... sealing foil (13 )… Sealing part

Claims (4)

[Claims] 1. A double-end type lamp comprising an envelope body for accommodating a filament or an electrode, and a small-diameter extension for forming a sealing portion protruding from at least one end of the envelope body. In a pressure-resistant envelope for use in a double-end type lamp, a curved portion formed from a shoulder portion of the envelope body to a small-diameter extension portion is integrally formed without a seam. Pressure resistant envelope. 2. A straight tube for forming an envelope is formed into a small diameter while heating a suitable portion of the straight tube, and cut at a proper portion with a small diameter portion or a large diameter portion or a combination of a small diameter portion and a large diameter portion to form a filament or A large-diameter envelope main body for accommodating an electrode, and a small-diameter extension portion for forming a sealing portion protruding from at least one end of the envelope main body, and a shoulder portion of the envelope main body A method for manufacturing an envelope for a double-ended lamp, characterized in that a curved surface portion formed from the thin film to the small-diameter extension portion is integrally formed without a seam. 3. A small diameter portion is formed by heating a suitable portion of the envelope forming straight pipe while heating the thin portion, and cutting the right portion with a small diameter portion or a large diameter portion or a combination of the small diameter portion and the large diameter portion. A large-diameter envelope body for accommodating a filament or an electrode by connecting an auxiliary cylinder to a small-diameter extension portion or a small-diameter extension portion for forming a sealing portion projecting from at least one end of the envelope body. A curved portion formed from the shoulder portion of the envelope body to the small-diameter extension portion is integrally formed without a seam. Manufacturing method for envelopes for double-ended lamps. 4. A double-end lamp using the pressure-resistant envelope according to claim 1, wherein a body-side end of a sealing portion formed at both ends of the envelope body of the envelope. A double-ended lamp characterized by the fact that the part in between is seamlessly integrated.