JP5225933B2 - Incandescent light bulb - Google Patents

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. 12 is an explanatory diagram showing an outline of the 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 disposed 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, the filament 55 is configured by connecting a plurality of coiled filament segments 56 made of, for example, tungsten, which are substantially parallel to the tube axis of the bulb 51, by a toe portion (not shown) (see FIG. Each filament segment 56 is a plane formed by the same plane (in FIG. 12, a direction perpendicular to the paper surface and a vertical direction so that the light from the filament 55 is efficiently irradiated. It is arranged along the top. The pinch seal portion 52 in the valve 51 is provided with a bottomed cylindrical 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 present inventors have studied the cause of such leakage light is generated, the reflected light L2 which light L1 from the filament 55 is caused to diffuse to the inner wall and the upper end surface of the base insulator 58 is incident to the lens 70 As a result, it was found that this was to cause halation. Moreover, since a general base insulator is formed of white ceramics, it has also been found that the reflected light L2 generated by irregular reflection becomes stronger and the induced halation becomes stronger.

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

The incandescent lamp according to the present invention includes a cylindrical bulb having a seal portion formed at one end thereof, a cylindrical cap insulator provided so as to surround the seal portion of the bulb, and a filament formed in a planar shape in the bulb In an incandescent bulb having
When the valve seal portion is arranged so as to face downward, the peripheral wall of the cap insulator is formed such that the area on the front side is higher than the area on the back side, with the plane relating to the filament as a boundary. ,
A point that is the same distance as the optical center distance from the center of the filament in the front side direction perpendicular to the plane related to the filament is defined as S, and a straight line extending in a direction perpendicular to the plane related to the filament and the base insulator When the intersection point with the outer peripheral edge at the upper end of the region portion on the front side in the peripheral wall is P, the region portion on the back side in the peripheral wall of the cap insulator in a cross section perpendicular to the plane related to the filament including the tube axis of the bulb Is located below the height level of the reference straight line passing through points S and P.

  In the incandescent lamp of the present invention, when the point away from the center of the lower end of the base insulator in the front side direction perpendicular to the plane of the filament by the same distance as the optical center distance is R, the peripheral wall of the base insulator It is preferable that the upper end of the region portion on the front side in is located below the height level of another reference line passing through the point R and the lower end of the filament.

According to the incandescent lamp of the present invention, the peripheral wall of the cap insulator is formed such that the region on the front side is higher than the region on the back side, with the plane relating to the filament as a boundary, and the region portion on the back side Since the upper end of the base plate is positioned below the height level of the specific reference line, even if light from the filament is reflected on the inner wall surface of the region on the back side of the peripheral wall of the base insulator, this reflected light is Is blocked by the front side region of the peripheral wall, so that the halation caused by the light reflected from the filament being reflected by the base insulator can be suppressed. can do.
Further, in the cross section perpendicular to the plane related to the filament including the tube axis of the bulb, the upper end of the front side region portion of the peripheral wall of the cap insulator is positioned below the height level of another specific reference line. Therefore, it is possible to suppress the halation that occurs when the light from the filament is reflected by the upper end surface of the region on the front side of the peripheral wall of the base insulator. Can be reduced.

It is a front view for description which shows the structure in an example of the incandescent lamp of the present invention with a part of a bulb and a cap insulator broken. It is explanatory side view which shows the incandescent lamp of FIG. 1 with a specific reference straight line. It is explanatory drawing which shows the cap insulator in the incandescent lamp shown in FIG. 1, (a) is a top view, (b) is a front view, (c) is a side view, (d) is a rear view. It is an explanatory side view which shows the incandescent lamp of FIG. 1 with the other specific reference | standard straight line. 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 cap insulator, (a) is a top view, (b) is a front view, (c) is a side view, (d) is a rear view. It is explanatory drawing which shows the other modification of a cap insulator, (a) is a front view, (b) is a side view. It is explanatory drawing which shows the other modification of a nozzle | cap | die insulator, (a) is a front view, (b) is a side view. 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 front view showing a configuration of an example of an incandescent lamp according to the present invention, with a part of a bulb and a base insulator 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.
A filament 20 formed in a planar shape is arranged at the center position in the bulb 11 so that the center thereof is located on the tube axis of the bulb 11. The filament 20 in the illustrated example will be specifically described. The filament 20 includes a plurality (six in the illustrated example) of coil-shaped filament segments 21 made of, for example, tungsten each extending substantially parallel to the tube axis of the bulb 11. These filament segments 21 are arranged so that their respective axes are aligned on the same plane, and the end portions of the filament segments 21 are integrally connected to the end portions of the adjacent filament segments 21 by the toe portions 22. Thus, the entire filament 20 is planar.
One end 23 and the other end 24 of the filament 20 are wound around and connected to the distal ends of a pair of internal lead bars 25. Each base end portion of the internal lead bar 25 is connected to one end portion of a pair of metal foils 26 made of, for example, molybdenum, embedded in the pinch seal portion 12 so as to be spaced apart from each other. An external lead rod 27 made of, for example, tungsten, which extends outward from the pinch seal portion 12, is connected to the other end portion of each of the metal foils 26.

Between the pinch seal portion 12 and the filament 20 in the bulb 11, the first glass piece 30 on the column is fused and fixed to each of the internal lead rods 25, and the tube shaft of the bulb 11. A plurality (two in the illustrated example) of anchors 31 extending toward the filament 20 are fixed to the first glass piece 30, and the tip of the anchor 31 is disposed in the first glass piece 30. The portion is engaged with the flange 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 28 extending along the tube axis of the valve 11 is disposed in the bulb 11, and one end portion of the supporter 28 is fixed to the first glass piece 30, and the other end of the supporter 28 is arranged. The part enters the exhaust pipe remaining part 13 of the valve 11 and is fixed.
Between the exhaust pipe remainder 13 and the filament 20 in the bulb 11, a columnar second glass piece 32 is fused and fixed to the supporter 28, and the direction is 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.

The pinch seal portion 12 of the valve 11 is provided with a bottomed cylindrical cap insulator 40 made of ceramic, for example, so as to surround the pinch seal portion 12. The peripheral wall of the base insulator 40 in the illustrated example has a barrel portion 42 formed on the bottom portion 41, and a tapered portion 43 formed continuously from the barrel portion 42 so that the outer diameter thereof becomes smaller toward the tip. It is made up of.
A pair of pin-like connection terminals 44 extending perpendicularly to the bottom portion 41 are provided on the outer surface of the bottom portion 41 of the base insulator 40, and each of the connection terminals 44 is connected to the external lead rod 27 via the lead wire 35. Electrically connected.

As shown in FIG. 2, when the incandescent lamp 10 is arranged so that the pinch seal part 12 of the bulb 11 faces downward, the peripheral wall of the cap insulator 40 is formed on the front side (see FIG. 2). The left side region portion 40a is higher than the rear side region portion 40b. A point separated from the center O of the filament 20 by the same distance as the optical center distance L in the direction of the front side perpendicular to the plane related to the filament 20 is defined as S, and the plane F related to the filament 20 is perpendicular to the plane F. A cross section perpendicular to the plane F relating to the filament 20 including the tube axis of the bulb 11, where P is the intersection of the straight line extending in the direction and the outer peripheral edge of the upper end of the front-side region portion 40 a on the peripheral wall of the cap insulator 40 (FIG. 2, the upper end of the region portion 40 b on the back side of the peripheral wall of the base insulator 40 is higher than the height level of a specific reference straight line A passing through the points S and P. Located below.
Here, the “optical center distance” means a distance from the center of the filament 20 to the lower end of the base insulator, that is, the outer surface of the bottom. For example, a reflector in a spotlight generally has the optical center distance as a radius. It is formed along a hemispherical surface.

  As shown in FIG. 3, the base insulator 40 in the illustrated example has a groove portion D formed at a location where a plane related to the filament 20 on the peripheral wall is located, and the region portion 40 a on the front side of the groove portion D is The upper end is formed in a state extending to a position higher than the first glass piece 30, and thereby, the front side of the first glass piece 30 is surrounded by the region portion 40 a on the front side in the peripheral wall of the cap insulator 40. . On the other hand, in the region portion 40b on the back side from the groove portion D of the base insulator 40, the upper end thereof is lower than the upper end of the region portion 40a on the front side, and the upper end surface of the region portion 40b has a semicircular shape. The notch K is formed.

  Moreover, in the incandescent lamp 10 of this example, as shown in FIG. 4, it is the same as the optical center distance L from the lower end of the cap insulator 40, that is, the outer surface of the bottom 41 to the front side direction perpendicular to the plane F related to the filament 20. When R is a point separated by a distance, the upper end of the region portion 40a on the front side of the peripheral wall of the cap insulator 40 is higher than the height level of another specific reference line B passing through the point R and the lower end of the filament 20. Located below.

  The width of the upper end surface of the region portion 40a on the front side of the peripheral wall of the base insulator 40 (thickness of the peripheral wall) is preferably 1.5 mm or less, so that the light from the filament 20 is the upper end surface of the region portion 40a. It is possible to reduce the reflected light that is reflected by the light, and it is possible to suppress the halation caused by the light from the filament being reflected by the upper end surface of the region on the front side of the peripheral wall of the cap insulator.

Moreover, in the area | region part 40a of the front side in the surrounding wall of the cap insulator 40, it is preferable that the upper end surface and the upper end area | region of the inner peripheral wall surface following it are non-light-reflective.
In order to impart non-light reflectivity, for example, black coating may be applied to the surface region.
Moreover, it is preferable that the upper end area | region made into the non-light-reflective property in the inner peripheral wall surface of the area | region part 40a of the front side is an area | region from the upper end of the said area part 40a to the position away 5 mm or more below.
By adopting such a configuration, it is possible to suppress halation caused by light reflected from the filament 20 being reflected by the upper end surface and the inner peripheral wall surface of the front-side region portion 40a on the peripheral wall of the cap insulator 40.

According to the incandescent lamp 10 described above, the peripheral wall of the cap insulator 40 is formed such that the area portion 40a on the front side is higher than the area portion 40b on the back side, with the plane F relating to the filament 20 as a boundary. Since the upper end of the side region portion 40 b is positioned below the height level of the specific reference line A, the light from the filament 20 is reflected on the inner peripheral wall surface of the rear side region portion 40 b on the peripheral wall of the cap insulator 40. However, since this reflected light is blocked by the front-side region portion 40b on the peripheral wall of the base insulator 40, it is possible to suppress the halation that occurs when the light from the filament 20 is reflected by the base insulator 40. For example, leakage light can be reduced when used as a light source for a spotlight.
Further, the upper end of the front-side region portion 40a in the peripheral wall of the base insulator 40 is positioned below the height level of another specific reference straight line B, so that the light from the filament 20 is transmitted in the peripheral wall of the base insulator 40. It is possible to suppress halation caused by being reflected by the upper end surface of the front-side region portion 40a. Therefore, for example, when used as a light source of a spotlight, leakage light can be further reduced.

FIG. 5 is an explanatory diagram showing an outline of the configuration of a spotlight including 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 45 that reflects light from the incandescent bulb 10 is disposed behind the incandescent bulb 10. The reflecting surface of the reflecting mirror 45 is formed along a spherical surface Q having a radius that is the optical center distance L of the incandescent bulb 10. Further, in front of the incandescent lamp 10, a lens 46 that collects the light from the incandescent lamp 10 and the reflected light from the reflecting mirror 45 has an optical axis perpendicular to the plane F of the filament 20 from the center of the filament 20. It is arranged so as to be located on a straight line extending in any direction.
In such a spotlight, light emitted from the filament 20 of the incandescent bulb 10 is reflected directly or after being reflected by the reflecting mirror 45, and then collected by the lens 46, for example, illumination in which 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, halation caused by reflection of light from the filament 20 to the cap insulator 40 is suppressed, so that leakage light can be reduced. Can be planned.

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, the base insulator is not limited to the shape shown in FIG. 3, and as shown in FIG. 6, a step portion is formed between the upper end of the front-side region portion 40a and the upper end of the rear-side region portion 40b. By doing so, the area part 40a on the front side may be formed higher than the area part 40b on the back side. Further, as shown in FIG. 7, the base insulator has a rectangular bottomed cylindrical shape, and the outer wall surface on the front side and the outer wall surface on the back side are formed in a tapered shape, and the upper side of the region portion 40b on the back side is formed. By forming the end surface into a tapered shape, the front-side region portion 40a may be formed to be higher than the back-side region portion 40b. Further, as shown in FIG. 8, the base insulator has a rectangular bottomed cylindrical shape, and the outer wall surface on the front side and the outer wall surface on the rear side are formed in a tapered shape, and the upper end of the region portion 40a on the front side is formed. By forming a step portion between the upper portion and the upper end of the rear-side region portion 40b, the front-side region portion 40a may be formed higher than the rear-side region portion 40b. Further, the cylindrical body forming the base insulator is not limited to a circular or rectangular shape, but may be a hexagonal shape or other polygonal shapes.
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. 9A, 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. 9 (b). As shown in FIG. 9C, the single filament segment 21 may be curved in a wave shape.

<Example 1>
An incandescent lamp according to the present invention was manufactured using a bulb, a filament, and a cap insulator having the following specifications in accordance with the configuration shown in FIGS.
The bulb is made of quartz glass, has a total length of 113 mm excluding the remaining exhaust pipe, an inner diameter of 20 mm, an outer diameter of 23 mm, and a pinch seal portion of 25 mm in length.
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 base insulator has an outer diameter of 35 mm, a height (length in the axial direction) of 53 mm, and a taper portion from the upper end to 10 mm. Moreover, the width | variety (thickness of a surrounding wall) of the upper end surface of the area | region part of the front side in the surrounding wall of a cap insulator is 1.0 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.
The incandescent lamp has an optical center distance of 90 mm, and the upper end of the region on the back side of the peripheral wall of the cap insulator is below the height level of a specific reference line passing through the points S and P. The upper end of the front side region portion of the peripheral wall of the cap insulator is positioned below the height level of another specific reference line passing through the point R and the lower end of the filament.

Next, according to the configuration shown in FIG. 5, 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 base was changed to one having the following specifications, 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. 10 and 11, in the spotlight according to Comparative Example 1, there is leakage light due to halation caused by light reflected from the base insulator at the measurement position G, whereas Example 1 According to the spotlight according to the above, it was confirmed that leakage light due to halation was reduced at the measurement position G.

DESCRIPTION OF SYMBOLS 10 Incandescent light bulb 11 Bulb 12 Pinch seal part 13 Exhaust pipe remainder 20 Filament 21 Filament segment 22 Tobe part 23 End of filament 24 End of filament 24 Internal lead rod 26 Metal foil 27 External lead rod 28 Supporter 30 1st glass Piece 31 Anchor 32 Second glass piece 33 Anchor 35 Lead wire 40 Cap insulator 40a Front side region portion 40b Rear side region portion 41 Bottom portion 42 Body portion 43 Taper portion 44 Connection terminal 45 Reflector 46 Lens 50 Incandescent light bulb 51 Valve 52 Pinch seal part 53 Exhaust pipe remaining part 55 Filament 56 Filament segment 58 Base insulator 60 Reflector 70 Lens A Specific reference straight line B Other specific reference line D Groove part F Plane related to filament K Notch O Filament Center of

Claims (2)

In an incandescent bulb having a cylindrical bulb having a seal portion formed at one end thereof, a cylindrical cap insulator provided so as to surround the seal portion of the bulb, and a filament formed in a planar shape in the bulb,
When the valve seal portion is arranged so as to face downward, the peripheral wall of the cap insulator is formed such that the area on the front side is higher than the area on the back side, with the plane relating to the filament as a boundary. ,
A point that is the same distance as the optical center distance from the center of the filament in the front side direction perpendicular to the plane related to the filament is defined as S, and a straight line extending in a direction perpendicular to the plane related to the filament and the base insulator When the intersection point with the outer peripheral edge at the upper end of the region portion on the front side in the peripheral wall is P, the region portion on the back side in the peripheral wall of the cap insulator in a cross section perpendicular to the plane related to the filament including the tube axis of the bulb The incandescent lamp is characterized in that the upper end of the incandescent lamp is positioned below the height level of the reference straight line passing through the points S and P.   The upper end of the region on the front side of the peripheral wall of the base insulator when R is a point separated from the center of the base end of the base insulator by the same distance as the optical center distance in the direction of the front side perpendicular to the plane related to the filament The incandescent lamp according to claim 1, wherein is positioned below a height level of another reference line passing through the point R and the lower end of the filament.

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