JP2013145764A - Incandescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an incandescent lamp suppressed in halation caused by reflection of light from a filament against a bulb, and, small in leakage of light when used, for example, as a light source of a spotlight.SOLUTION: In an incandescent lamp (10) including a bulb (11) comprising cylindrical quartz glass and a filament (20) which is disposed in the bulb (11) and formed in a planar form, the bulb (11) has a swollen part (15) in a peripheral wall including a region facing the filament (20), the swollen part being formed along an elliptic spherical surface having two focal points (P1, P2) present on a plane relating to a filament formation region (T). In the swollen part (15), the two focal points (P1, P2) of an elliptic sphere relating to the swollen part (15) are present at positions apart from the filament formation region (T), on the plane relating to the filament formation region (T).

Description

  The present invention relates to a high-power incandescent light bulb suitable as a light source for an illumination device such as a spotlight used for lighting in a studio or a stage.

  For example, a lighting device such as a spotlight is used as a means for illuminating a studio or a stage, and a high-power incandescent bulb is widely used as the light source of such a lighting device (see Patent Document 1). .

  FIG. 11 is an explanatory diagram showing an outline of a configuration of a spotlight including a conventional incandescent bulb. This spotlight has an incandescent bulb 50, a hemispherical reflecting mirror 60 that reflects light from the incandescent bulb 50 is arranged behind the incandescent bulb 50, and an incandescent bulb is placed in front of the incandescent bulb 50. A lens 70 that collects the light from 50 and the reflected light from the reflecting mirror 60 is disposed. The incandescent bulb 50 has a cylindrical bulb 51 made of quartz glass having a pinch seal portion 52 formed at one end and an exhaust pipe remaining portion 53 formed at the other end. The formed filament 55 is arranged. Specifically, as shown in FIG. 11, the filament 55 includes a plurality of coiled filament segments 56 made of, for example, tungsten, each extending substantially parallel to the tube axis of the valve 51, and connected by a toe portion (not shown). Each filament segment 56 is on the same plane (on a plane formed by a direction perpendicular to the plane of the paper and an up-down direction in FIG. 11) so that the light from the filament 55 is efficiently irradiated. ) Are arranged along the line. Further, the pinch seal portion 52 in the valve 51 is provided with a cap insulator 58.

  In a spotlight having such an incandescent bulb 50, from the viewpoint of production or the like, for example, illuminating only an illumination target area where an illumination target object such as a person is located, that is, the illumination target area is irradiated with light, and It is required that light is not irradiated to areas other than the illumination target area, for example, peripheral areas of the illumination target area.

JP 2001-319624 A

However, in the spotlight having the conventional incandescent bulb 50, there is leakage light other than the light directly emitted from the filament 55 of the incandescent bulb 50, so that light is also irradiated to the peripheral region of the illumination target region, It is difficult to illuminate only the area where the illumination object is located.
The reason for such leakage light is that the light L1 from the filament 55 is reflected by the inner wall surface of the bulb 51 or the reflected light L2 that is reflected by the reflecting mirror 70 is reflected by the outer wall surface of the bulb 51. It is thought that halation is caused by the reflected light.

  The present invention has been made on the basis of the circumstances as described above, and its purpose is to suppress halation caused by reflection of light from a filament to a bulb, and leakage when used as a light source of a spotlight, for example. The object is to provide an incandescent light bulb with less light.

The incandescent lamp of the present invention is an incandescent lamp having a bulb made of cylindrical quartz glass and a filament formed in a flat shape disposed in the bulb.
The bulb has a bulging portion formed along an elliptical sphere in which two focal points exist on a plane related to the filament forming region in a peripheral wall portion including a region facing the filament,
The bulging portion is characterized in that two focal points of the ellipsoidal sphere relating to the bulging portion are on a plane relating to the filament forming region and deviated from the filament forming region.

In the incandescent lamp of the present invention, when a glass piece for holding the filament is arranged in the bulb, a light shielding film is formed on a peripheral wall portion of the bulb surrounding the glass piece. Is preferred.
In addition, when a seal portion is formed at one end of the bulb and a glass piece for holding the filament is disposed between the seal portion and the filament in the bulb, the seal It is preferable that the base is provided with a cap insulator so as to cover a portion surrounding the glass piece in the bulb.

  According to the incandescent lamp of the present invention, the bulb has an bulging portion in the peripheral wall portion including the region facing the filament, and the bulging portion has an elliptical spherical surface in which two focal points exist on a plane related to the filament forming region. Therefore, even if the light from the filament is reflected on the inner wall of the bulb, the reflected light travels toward the filament forming region, and the light from the reflector is also reflected on the outer wall of the bulb. This reflected light travels toward the reflecting mirror even if it is reflected by the light. Therefore, it is possible to suppress the halation caused by the light from the filament being reflected by the bulb. Leakage light can be reduced.

  In addition, since the bulging portion is formed along an elliptical spherical surface where the two focal points are located away from the filament forming region, the filament forming region is positioned between the two focal points. Even if the light is radiated from this part, the reflected light reflected by the inner wall of the bulb surely travels toward the filament forming region, so that the halation caused by the light reflected from the filament being reflected by the bulb is further increased. Can be suppressed.

  Further, when a glass piece for holding the filament is disposed in the bulb, a light shielding film is formed on the peripheral wall portion of the bulb that surrounds the glass piece, so that the light from the filament is glass. Even if it is reflected by the piece, the reflected light is blocked by the light-shielding film, so that it is possible to prevent the reflected light from the glass piece from being emitted outside.

  In addition, when a glass piece is disposed between the seal part and the filament in the bulb, the pinch seal part is provided with a cap insulator so as to cover the portion surrounding the glass piece in the bulb. Even if the light from the glass piece is reflected by the glass piece, the reflected light is blocked by the cap insulator, so that it is possible to prevent the reflected light from the glass piece from being emitted to the outside.

It is explanatory drawing which fractures | ruptures a part of bulb | bulb and shows the structure in the incandescent lamp which concerns on the 1st Embodiment of this invention. It is explanatory drawing which fractures | ruptures a valve | bulb and shows the structure of the principal part in the incandescent lamp which concerns on 1st Embodiment. It is explanatory drawing which shows a confirmation means about the shape of the bulging part of the bulb | bulb in the incandescent lamp of this invention, (a) is explanatory drawing seen from the upper side of an incandescent lamp, (b) is explanation demonstrated from the side of the incandescent lamp FIG. It is explanatory drawing which fractures | ruptures a valve | bulb and shows the structure of the principal part in the incandescent lamp which concerns on the 2nd Embodiment of this invention. It is explanatory drawing which fractures | ruptures a part of bulb | bulb and shows the structure in the incandescent lamp which concerns on the 3rd Embodiment of this invention. It is explanatory drawing which fractures | ruptures a part of bulb | bulb and shows the structure in the incandescent lamp which concerns on the 4th Embodiment of this invention. It is explanatory drawing which shows the outline of a structure of the spotlight provided with the incandescent lamp of this invention. It is explanatory drawing which shows the modification of a filament. It is a figure which shows the illumination intensity distribution of the spotlight which concerns on Example 1. FIG. It is a figure which shows the illumination intensity distribution of the spotlight which concerns on the comparative example 1. FIG. It is explanatory drawing which shows the outline of a structure of the spotlight provided with the conventional incandescent lamp.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is an explanatory view showing a configuration of the incandescent bulb according to the first embodiment of the present invention with a part of a bulb broken away.
The incandescent bulb 10 has a cylindrical bulb 11 made of quartz glass. A pinch seal portion 12 is formed at one end of the bulb 11, and an exhaust pipe remaining portion 13 is formed at the other end of the bulb 11. Has been. Further, the pinch seal portion 12 of the valve 11 is provided with a cap insulator 35.

A filament 20 formed in a planar shape is disposed at a central position in the bulb 11. More specifically, the filament 20 has a plurality (six in the illustrated example) of coil-shaped filament segments 21 each extending substantially parallel to the tube axis of the bulb 11, for example, and these filament segments. 21 is arranged such that the respective axes are aligned along the same plane, and the end of the filament segment 21 is integrally connected to the end of the adjacent filament segment 21 by the toe portion 22, thereby The entire filament 20 is flat.
One end 23 of the filament 20 is wound and connected to the tip of one internal lead rod 25, and the other end 24 of the filament 20 is wound and connected to the tip of the other internal lead rod 26. Has been. The base end portions of one internal lead rod 25 and the other internal lead rod 26 are connected to a pair of metal foils (not shown) made of, for example, molybdenum embedded in the pinch seal portion 12 so as to be separated from each other. In this state, the pinch seal portion 12 is hermetically fused and fixed.

Between the pinch seal portion 12 and the filament 20 in the bulb 11, the first glass piece 30 on the pillar is fused and fixed to each of one internal lead rod 25 and the other internal lead rod 26. In this state, the first glass piece 30 is arranged along a direction substantially perpendicular to the tube axis of the bulb 11, and a plurality (two in the illustrated example) of anchors 31 extending toward the filament 20 are disposed on the first glass piece 30. Is fixed, and the tip portion of the anchor 31 is engaged with the toe portion 22 of the filament 20, whereby the filament 20 is supported by the first glass piece 30 via the anchor 31.
Further, a rod-like supporter 27 extending along the tube axis of the valve 11 is disposed in the bulb 11, and one end portion of the supporter 27 is fixed to the first glass piece 30, and the other end of the supporter 27 is arranged. The part enters the exhaust pipe remaining part 13 of the valve 11 and is fixed.
Between the exhaust pipe remaining portion 13 and the filament 20 in the bulb 11, a columnar second glass piece 32 is fused and fixed to the supporter 27, and is in a direction substantially perpendicular to the tube axis of the bulb 11. A plurality (three in the illustrated example) of anchors 33 extending toward the filament 20 are fixed to the second glass piece 32, and the distal end of the anchor 33 is attached to the filament 20. The filament portion 20 is supported by the second glass piece 32 via the anchor 33.

  As shown in FIG. 2, the bulb 11 has a peripheral wall portion including a region facing the filament 20 and a center P along a spherical surface existing on a plane related to the filament forming region T where the filament 20 is located. A bulging portion 15 having a hemispherical outer shape is formed. Specifically, the bulging portion 15 has a dimension D in the tube axis direction larger than a dimension F in the tube axis direction in the filament forming region T.

In the present invention, the bulge portion of the valve can be formed, for example, as follows. First, a bulging portion molding die having a recess (a hemispherical shape in the example of FIG. 2) conforming to the outer shape of the bulging portion to be formed is prepared.
Next, a cylindrical valve material having an exhaust pipe part at one end (one with no bulging part formed) is prepared, and the bulging part forming part of this valve material is softened by heating, for example, with a burner. The bulging portion forming portion is covered with a bulging portion molding die to close the exhaust pipe portion of the valve material, and a gas introduction pipe is attached to the other end of the valve material so that the inside of the valve material is sealed. Then, by introducing a gas such as nitrogen gas from the gas introduction pipe into the valve material and increasing the internal pressure of the valve material, the softened bulge portion forming portion of the valve material is formed into a bulge portion molding die. The bulging portion having a required shape can be formed by inflating into a shape along the recess, cooling the valve material, and releasing from the bulging portion molding die.

Further, the detailed shape of the bulging portion can be confirmed using an X-ray transmission device (for example, “μRay 5500” manufactured by MATSUSADA).
More specifically, as shown in FIGS. 3A and 3B, the camera 11 of the X-ray transmission device is placed on the side of the incandescent bulb 10 and X-ray imaging is performed, whereby the bulb 11 and the filament 20 are arranged. An X-ray image of the side cross-section is obtained. At this time, the camera C is arranged so that the center position of the filament 20 is the center of the image. Then, by analyzing the obtained X-ray image, the shape of the bulging portion 15 and the center position of the sphere related to the bulging portion 15 (in the second embodiment to be described later, the bulging portion 15 The first focus position and the second focus position of the elliptical sphere can be confirmed.

  According to the incandescent bulb 10 described above, the bulb 11 has the bulging portion 15 on the peripheral wall portion including the region facing the filament 20, and the bulging portion 15 exists on the plane related to the filament forming region. By forming along the spherical surface, even if the light from the filament 20 is reflected by the inner wall of the bulb 11, the reflected light travels toward the filament forming region, and the light from the reflecting mirror. Is reflected by the outer wall of the bulb 11, the reflected light travels toward the reflecting mirror, so that the halation caused by the light from the filament 20 being reflected by the bulb 11 can be suppressed. Leakage light can be reduced when used as a light source.

FIG. 4 is an explanatory view showing the structure of the main part of the incandescent lamp according to the second embodiment of the present invention, with the bulb broken.
In the incandescent bulb 10, the bulb 11 is disposed on the peripheral wall portion including the region facing the filament 20 on the plane related to the filament forming region T where the first focal point P1 and the second focal point P2 are located. A bulging portion 15 having a semi-elliptical spherical outer shape is formed along the existing elliptical spherical surface. In the illustrated example, the first focal point P1 of the ellipsoidal sphere related to the bulging portion 15 is on a plane related to the filament forming region T and is located at a position off the other end side of the bulb 11 from the filament forming region T. The second focal point P <b> 2 exists on a plane related to the filament forming region T and is located at a position deviated from the filament forming region T to one end side of the bulb 11. Other configurations of the incandescent bulb 10 of this example are the same as those of the incandescent bulb 10 shown in FIGS. 1 and 2.

According to such an incandescent bulb 10, in addition to the same effects as those of the incandescent bulb 10 according to the first embodiment, the following effects can be obtained.
That is, the bulging portion 15 of the bulb 11 is formed along an elliptical spherical surface in which each of the first focal point P1 and the second focal point P2 deviates from the filament forming region T, whereby the first focal point P1 and Since the filament forming region T is positioned between the second focal points P2, the reflected light reflected from the inner wall of the bulb 11 is surely reflected by the filament forming region T, regardless of the light emitted from any part of the filament 20. Therefore, the halation caused by reflection of light from the filament 20 by the bulb can be further suppressed.

FIG. 5 is an explanatory view showing a configuration of an incandescent lamp according to the third embodiment of the present invention with a part of a bulb broken away.
In the incandescent bulb 10, a light shielding film 16 is formed on the entire surface of one end portion of the bulb 11 including the peripheral wall portion of the bulb 11 surrounding the second glass piece 32 and the exhaust pipe remaining portion 13. The material for forming the light shielding film 16 is not particularly limited as long as it does not transmit light, and for example, a black paint can be used. Other configurations of the incandescent lamp 10 of this example are the same as those of the incandescent lamp 10 shown in FIG. 1 and FIG. 2 or FIG.

According to such an incandescent bulb 10, in addition to the same effects as those of the incandescent bulb 10 according to the first embodiment, the following effects can be obtained.
That is, by forming the light shielding film 16 on the peripheral wall portion of the bulb 11 surrounding the second glass piece 32, the reflected light is shielded even if the light from the filament 20 is reflected by the second glass piece 32. Since it is blocked by the film 16, it is possible to prevent the reflected light from the second glass piece 32 from being radiated to the outside.

FIG. 6 is an explanatory diagram showing a configuration of an incandescent lamp according to the fourth embodiment of the present invention with a part of the bulb broken away.
The cap insulator 35 in the incandescent bulb 10 has a larger axial dimension than the cap insulator 35 in the incandescent bulb 10 according to the first embodiment. The cap insulator 35 is a pinch seal portion of the valve 11. 12 is provided so as to cover the entire surface of the portion surrounding the first glass piece 30 in the bulb 11. The other configuration of the incandescent bulb 10 in this example is the same as that of the incandescent bulb 10 shown in FIG.

According to such an incandescent bulb 10, in addition to the same effects as those of the incandescent bulb 10 according to the first embodiment, the following effects can be obtained.
That is, the pinch seal portion 12 of the bulb 11 is provided with the cap insulator 35 so as to cover the portion surrounding the first glass piece 30 in the bulb 11, so that the light from the filament 20 is applied to the first glass piece 30. Even if the light is reflected, the reflected light is blocked by the cap insulator 35, so that the reflected light from the first glass piece can be prevented from being radiated to the outside.

FIG. 7 is an explanatory diagram showing an outline of the configuration of a spotlight provided with the incandescent bulb of the present invention. The spotlight has an incandescent bulb 10 shown in FIG. 1, for example, and a hemispherical reflecting mirror 40 that reflects light from the incandescent bulb 10 is disposed behind the incandescent bulb 10. The lens 45 which condenses the light from the incandescent lamp 10 and the reflected light from the reflecting mirror 40 is disposed. Further, the incandescent bulb 10 is arranged such that the bulging portion 15 of the bulb 11 faces the reflecting mirror 40. Here, the bulging portion 15 in the bulb 11 may be hemispherical as shown in FIG. 2 or hemispherical as shown in FIG.
In such a spotlight, the light emitted from the filament 20 of the incandescent bulb 10 is reflected directly or after being reflected by the reflecting mirror 40, and then collected by a lens 45, for example, an illumination object such as a person is located. The target area is irradiated.
Thus, according to such a spotlight, since it has the incandescent bulb 10 of the present invention, even if the light from the filament 20 is reflected on the inner wall of the bulb 11, the reflected light travels toward the filament forming region. In addition, even if the light from the reflecting mirror 40 is reflected on the outer wall of the bulb 11, the reflected light travels toward the reflecting mirror 40, so that the light from the filament 20 is reflected on the bulb 11. As a result, halation that occurs is suppressed, so that leakage light can be reduced.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.
For example, when the bulging portion 15 of the bulb 11 is formed along an elliptical spherical surface where each of the first focal point P1 and the second focal point P2 exists on the plane related to the filament forming region T, the bulging portion 15 The first focal point P1 and the second focal point P2 of the elliptical sphere may be present in the filament forming region T.
Further, the filament 20 is not limited to the shape shown in FIG. 1 as long as it is formed in a planar shape. For example, as shown in FIG. 8A, a plurality of filament segments 21 are arranged in parallel. The two filament segments 21 are arranged in an M shape as shown in FIG. 8B, which are arranged and arranged so that the height levels of both ends of the adjacent filament segments 21 are different from each other. As shown in FIG. 8C, the single filament segment 21 may be curved in a wave shape.

<Example 1>
In accordance with the configuration shown in FIGS. 1 and 2, an incandescent lamp according to the present invention was manufactured using a bulb and a filament having the following specifications.
The bulb is made of quartz glass, has a total length excluding the exhaust pipe remaining portion of 113 mm, an inner diameter of 20 mm, an outer diameter of 23 mm, a radius of a sphere related to the bulge portion of 18.5 mm, and a tube axis direction in the bulge portion. The dimension is 28.5 mm, and the center of the sphere is on the plane related to the filament formation region and exists at the center position of the filament formation region. The length of the pinch seal portion is 25 mm.
The filament is made of tungsten, and the length of each of the six filament segments is 14 mm. The dimension in the tube axis direction in the filament forming region is 14 mm, and the dimension in the direction perpendicular to the tube axis direction is 12.7 mm.
The produced incandescent lamp has a rated power of 1000 W, a total luminous flux of 21600 lm, and a color temperature of 3020K.

Next, according to the configuration shown in FIG. 7, a spotlight was produced using the incandescent bulb, a lens having a diameter of 180 mm, and a spherical reflector having a radius of 90 mm. Here, the lens, the incandescent bulb, and the spherical reflector were arranged so that the distance from the incandescent bulb to the lens was 90 mm, and the distance from the incandescent bulb to the spherical reflector was 90 mm.
And the said spotlight was turned on and the illumination intensity distribution of the irradiation surface of the light from a spotlight was measured. The results are shown in FIG.

<Comparative example 1>
An incandescent bulb and a spotlight having the same configuration as in Example 1 were prepared except that the bulb was not formed with a bulging portion, and the illuminance distribution on the surface irradiated with light from the spotlight was measured. The results are shown in FIG.

  As is apparent from the results of FIGS. 9 and 10, in the spotlight according to Comparative Example 1, there is leakage light due to halation caused by reflection of light at the measurement positions S <b> 1 and S <b> 2. According to the spotlight according to No. 1, it was confirmed that leakage light due to halation was reduced at the measurement positions S1 and S2.

DESCRIPTION OF SYMBOLS 10 Incandescent light bulb 11 Bulb 12 Pinch seal part 13 Exhaust pipe remainder part 15 Expansion part 16 Light shielding film 20 Filament 21 Filament segment 22 Tobe part 23 One end part of a filament 24 The other end part of a filament 25 One internal lead rod 26 The other internal lead Rod 27 Supporter 30 First glass piece 31 Anchor 32 Second glass piece 33 Anchor 35 Base insulator 40 Reflector 45 Lens 50 Incandescent light bulb 51 Valve 52 Pinch seal part 53 Exhaust pipe remainder 55 Filament 56 Filament segment 58 Base insulator 60 Reflection Mirror 70 Lens C Camera T Filament formation region P Center P1 First focus P2 Second focus

Claims (3)

In an incandescent bulb having a bulb made of cylindrical quartz glass and a filament formed in a flat shape disposed in the bulb,
The bulb has a bulging portion formed along an elliptical sphere in which two focal points exist on a plane related to the filament forming region in a peripheral wall portion including a region facing the filament,
An incandescent light bulb characterized in that the bulging portion has two focal points of an elliptic sphere related to the bulging portion on a plane related to the filament forming region and deviated from the filament forming region.   The incandescent lamp according to claim 1, wherein a glass piece for holding the filament is disposed in the bulb, and a light-shielding film is formed on a peripheral wall portion of the bulb surrounding the glass piece. light bulb.   A seal portion is formed at one end of the bulb, and a glass piece for holding the filament is disposed between the seal portion and the filament in the bulb. The incandescent lamp according to claim 1 or 2, wherein a cap insulator is provided so as to cover a portion surrounding the glass piece in the bulb.

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