JPH09161732A - Tungsten halogen lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further improve the efficiency increasing rate by effectively feeding back infrared rays radiated from a filament to the filament. SOLUTION: A spheroidal part 3 is formed in a bulb 1, and a chip-off part 2 is arranged on one end side of this spheroidal part 3, and a cylinder part 5 and a sealing part 6 continuously arranged in this cylinder part 5 are arranged on the other end side, respectively. A filament 7 is arranged in the coaxial direction with the bulb 1 inside of the bulb 1, and this filament 7 is arranged in the spheroidal part 3. An infrared ray reflecting film 4 is formed on an outside surface of the spheroidal part 3. Both ends of the filament 7 are arranged between two focuses of the spheroidal part 3 of the bulb 1, and when an outside diameter of the cylinder part 5 is denoted by Dmm and a minor axis length of the spheroidal part 3 is denoted by (a) mm, it has the constitution to satisfy the relationship of (0.55<=D/2a<=0.75).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halogen bulb having a spheroidal portion and an infrared reflecting film on the surface of the spheroidal portion.

[0002]

2. Description of the Related Art As conventional halogen light bulbs, for example,
Tip-off part, tip-off part side cylinder part, spheroid part,
Inside the glass bulb formed by sequentially connecting the sealing portion side cylindrical portion and the sealing portion, a filament is provided in a portion coaxial with the glass bulb and where the spheroidal portion exists. On the surface of the ellipsoid, an infrared reflection film that reflects the infrared rays emitted from the filament toward the filament is provided, and the power saving rate, that is, the efficiency increase rate is 15%.
An improved one is known (Japanese Patent Laid-Open No. 4-47660).
No.).

In such a halogen light bulb, the infrared rays emitted from the filament are reflected by the infrared reflecting film and returned to the filament to improve the lamp efficiency.

[0004]

However, in the case of the above-mentioned conventional halogen bulb, however, a portion other than the spheroidal portion provided with the infrared reflection film from the filament, that is, the tip-off portion, the tip-off portion side cylindrical portion, The infrared rays radiated toward the sealing portion side cylindrical portion and the sealing portion have been transmitted as they are outside the bulb.

Further, even if the entire bulb is covered with an infrared reflecting film, the feedback ratio is small, especially in the tip-off side cylindrical portion, and infrared rays cannot be effectively returned to the filament.

An object of the present invention is to provide a halogen light bulb which can effectively return infrared rays emitted from the filament to the filament and further improve the efficiency increase rate.

[0007]

In order to achieve the above object, a halogen bulb of the present invention is a glass bulb having a tip-off portion, a spheroidal portion, a tubular portion, and a sealing portion, which are successively formed. Inside the, in the same direction as the glass bulb,
Further, a filament is provided in a portion where the spheroid portion is present, an infrared reflection film is formed on the surface of the spheroid portion of the glass bulb, and the outer diameter of the cylindrical portion is D
(Mm) and the minor axis length of the spheroid is a (mm)
In this case, the structure satisfies the relationship of 0.55 ≦ D / 2a ≦ 0.75.

As a result, the infrared rays emitted from the filament can be efficiently reflected back to the filament again by the infrared reflection film formed on the surface of the spheroid, so that the infrared feedback rate can be increased.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises: a glass bulb having a tip-off portion, a spheroidal portion, a tubular portion, and a sealing portion, which are formed in order, In the coaxial direction, and a filament is provided in a portion where the spheroid portion is present, an infrared reflection film is formed on the surface of the spheroid portion of the glass bulb,
When the outer diameter of the cylindrical portion is D (mm) and the minor axis length of the spheroidal portion is a (mm), 0.55 ≦ D / 2a ≦
It has a configuration that satisfies the relationship of 0.75.

As a result, the spheroidal portion can be made larger due to the absence of the tubular portion on the tip-off portion side, and the outer diameter of the tubular portion on the sealing portion side can be made smaller. The infrared ray-reflecting film formed in the above-mentioned section allows the infrared rays emitted from the filament to be efficiently reflected back to the filament.

According to a second aspect of the present invention, in the halogen light bulb according to the first aspect, the filament is present at least between two focal points of the spheroidal portion.

This makes it possible to further increase the infrared feedback rate. The invention according to claim 3 of the present invention is the halogen light bulb according to claim 1 or 2,
The outer diameter D (mm) of the cylindrical portion is 7 mm to 10 mm.

As a result, since the outer diameter of the tubular portion can be reduced, the spheroidal portion can be enlarged, the feedback rate of infrared rays radiated toward the tubular portion can be improved, and the halogen bulb can be manufactured. Sometimes it becomes easier to insert filaments into the glass bulb.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. FIG. 1 shows a single-ended metal halogen bulb that is an embodiment of the present invention.

A spheroidal portion 3 is formed on the quartz bulb 1. A tip-off portion 2 is provided at one end of the spheroidal portion 3 and a cylindrical portion 5 is provided at the other end thereof. Each of the sealing portions 6 provided in series is provided. A filament 7 having a length of 10 mm is provided inside the bulb 1 by a lead wire 9 coaxially with the bulb 1, and the filament 7 is provided inside the spheroid portion 3.
Further, on the outer surface of the spheroidal portion 3, an infrared reflection film 4 consisting of 18 layers for reflecting the infrared rays emitted from the filament 7 and returning them to the filament 7 is formed. FIG. 5 shows the spectral transmittance curve of the infrared reflecting film 4, and Table 1 shows the film constitution of the infrared reflecting film 4.

[0016]

[Table 1]

Both ends of the filament 7 are provided between the two focal points of the spheroidal portion 3 of the quartz bulb 1, so that infrared rays can be efficiently returned. The outer diameter D of the halogen bulb according to the present embodiment is 8 mm, and the minor diameter 2a of the spheroid portion 3 is 14 mm.

A base 8 is fixed to the sealing portion 6, and the base 8 is electrically connected to an external socket through the base 8.

With such a structure, the halogen bulb according to the present embodiment can have a feedback rate of 80% or more.

Next, the fact that infrared rays are reflected by the infrared reflecting film 4 (hereinafter referred to as a reflecting film) will be described with reference to FIG.

The emitted light 10 from the filament 7 passes through the bulb 1 and strikes the reflective film 4. Of these, visible light 11
Only the infrared rays are transmitted to the outside, and the infrared rays 12 are reflected inside the bulb 1. In the spheroid part 3, the reflected infrared rays 12 are reflected in a direction symmetrical with respect to the emitted light 10 about the normal line 13 of the spheroid part. Here, since the filament 7 exists between the focal points of the spheroidal portion 3, the infrared rays 12 are efficiently returned to the filament 7.

Infrared rays 12 emitted from the filament 7
Geometrically, the rate at which is returned to the filament 7 is
The larger the spheroid part 3, the larger it becomes. That is, when the outer diameter D of the cylindrical portion 5 becomes larger than the minor diameter 2a of the spheroidal portion 3, the spheroidal portion 3 becomes smaller. Therefore, in order to improve the feedback rate in the cylindrical portion 5, it is required to make the outer diameter D of the cylindrical portion 5 as small as possible.

The above-mentioned conventional halogen bulb, that is,
Tip-off part, tip-off part side cylinder part, spheroid part,
Inside the glass bulb formed by sequentially connecting the sealing portion side cylindrical portion and the sealing portion, a filament is provided in a portion coaxial with the glass bulb and where the spheroidal portion exists. On the surface of the ellipsoid, an infrared reflection film that reflects the infrared rays emitted from the filament toward the filament is provided, and the power saving rate, that is, the efficiency increase rate is 15%.
In the improved one (hereinafter referred to as a conventional product), the outer diameter of the tip-off portion side cylindrical portion is almost the same as the outer diameter of the sealing portion side cylindrical portion, and the spheroidal portion 3 occupying the entire valve is small,
Geometrically, the return rate of infrared rays to the filament was small. On the other hand, in the present invention, the outer diameter of the tip-off portion is the cylindrical portion 5
Since the diameter is smaller than the outer diameter, the spheroidal portion 3 becomes larger and the feedback rate is improved.

In FIG. 3, the filament 7 has a length of 10 mm.
When the filament 7 is located at two focal points of the spheroid part 3, the outer diameter of the cylindrical part is D (mm), and the minor axis length of the spheroid part 3 is a (mm). Outer diameter D is 7 ~
It shows the relationship between the D / 2a and the infrared ray return rate to the filament 7 when the short axis 2a is changed within the range of 10 mm and the minor axis 2a, and it is shown that if the return rate is increased, the efficiency is also increased. Show.

As is apparent from FIG. 3, D / 2a = 0.
In the combination of 50, the return rate is as high as 80% or more,
There is a problem that the strength of the valve is reduced. That is,
When the spheroidal part 3 is formed by inflating a commonly used cylindrical valve having a thickness of 1 mm, the spheroidal part 3 partially has a wall thickness of 0.3 mm or less, and the withstand pressure strength is lowered to turn on the lamp. The chances of valve breakage during will increase.

The spheroidal portion 3 needs to have a wall thickness of at least 0.4 mm or more from the viewpoint of pressure resistance, and as a result of studies by the inventor, the spheroidal portion 3 is expanded by expanding a cylindrical valve.
It has been found that, in order to form the valve, in order to make the thickness of the valve 0.4 mm or more, D / 2a ≧ 0.55.

Next, FIG. 4 shows the relationship between the feedback rate and the efficiency increase rate. Here, the efficiency increase rate is the rate of increase in the energy efficiency of the lamp after the reflective film 4 is formed compared to before the reflective film 4 is formed.

In the case of the conventional product, since the cylindrical portions having the same diameter are present on both sides of the spheroidal portion, the feedback ratio is smaller than that of the structure of the present invention even if the value of D / 2a is the same. . As described above, in the conventional product, the power saving rate, that is, the efficiency increase rate was 15%. The infrared reflection film of the conventional product has eight layers. When the infrared reflection film 4 similar to that used in the present embodiment is formed on the spheroid of the conventional product, the efficiency increase rate is 30%. Met.

On the other hand, in the case of the present invention, since there is no cylindrical portion between the spheroidal portion 3 and the tip-off portion 2, there are more spheroidal portions 3 than the conventional product because of the absence of the cylindrical portion. Therefore, the return rate is high and the efficiency increase rate is also high.

In order to further improve the efficiency increase rate over the conventional 30%, as is apparent from FIG.
It is necessary to raise it to more than%. That is, from FIG. 3, D / 2
It must be a ≦ 0.75.

From the above, 0.55 ≦ D / 2a ≦ 0.75 is set in order to improve the efficiency increase rate as compared with the conventional product and to make the valve thickness of the spheroid part 0.4 mm or more. There is a need.

Next, an appropriate range of the outer diameter D (mm) of the cylindrical portion 5 will be described. If the outer diameter D of the cylindrical portion 5 is made as small as possible, the feedback rate is increased and the lamp efficiency is improved. However, when the outer diameter D of the cylindrical portion 5 is 6 mm, the inner diameter is 4
Since it is as small as mm, it causes a problem when the filament 7 or the like is inserted into the bulb during manufacture of the lamp. Therefore, the outer diameter D of the cylindrical portion 5 needs to be 7 mm or more.
However, if the outer diameter D of the cylindrical portion 5 is increased,
The minor axis 2a of the spheroid 3 also becomes large. For example, when the outer diameter D of the cylindrical portion 5 is 11 mm, D / 2a =
2a = 20mm when 0.55, outer diameter 11mm
It is too thick and has a long overall length compared to a halogen bulb with a cylindrical bulb that does not have a spheroid, which is contrary to the compactness of the halogen bulb, so it cannot be used. Further, when the outer diameter D of the cylindrical portion 5 is 10 mm, when the lower limit value of the short diameter 2a is D / 2a = 0.75, 2a = 13 mm, and the halogen bulb having a cylindrical bulb with the outer diameter of 11 mm described above. The size will be close to. Therefore, the outer diameter D of the cylindrical portion 5 is preferably 10 mm or less. Therefore, the outer diameter D of the cylindrical portion 5 is 7 to 10.
mm.

[0033]

As described above, the halogen bulb of the present invention can efficiently reflect the infrared rays emitted from the filament back to the filament again and improve the feedback rate, thus increasing the efficiency. The lamp efficiency can be improved and the lamp efficiency can be improved, and the wall thickness of the bulb can be 0.4 mm or more, so that the pressure resistance of the bulb can be increased.

[Brief description of the drawings]

FIG. 1 is a front view of a halogen bulb according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining that infrared rays are reflected by an infrared reflection film.

FIG. 3 is a diagram showing a relationship between D / 2a and a feedback rate.

FIG. 4 is a diagram showing a relationship between a feedback rate and an efficiency increase rate.

FIG. 5 is a diagram showing a spectral transmittance curve of an infrared reflective film.

[Explanation of symbols]

 1 Quartz bulb 2 Tip-off part 3 Spheroidal part 4 Infrared reflecting film 5 Cylindrical part 6 Sealing part 7 Filament

Claims (3)

[Claims] 1. A glass bulb formed by successively connecting a tip-off portion, a spheroidal portion, a tubular portion, and a sealing portion in the glass bulb in a direction coaxial with the glass bulb and in the spheroidal portion. Where a filament is provided, an infrared reflection film is formed on the surface of the spheroidal part of the glass bulb, and the outer diameter of the cylindrical part is D (mm), A halogen light bulb, wherein the relationship of 0.55 ≦ D / 2a ≦ 0.75 is satisfied, where the minor axis length is a (mm). 2. The halogen bulb according to claim 1, wherein the filament is arranged at least between two focal points of the spheroidal portion. 3. The halogen bulb according to claim 1, wherein the outer diameter D of the cylindrical portion is 7 mm to 10 mm.