JPH09293485A - Incandenscent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent glare and reduce the diameter of a glass tubular bulb so as to reduce the material cost and an applying quantity of a reflection film by disposing filaments for running and passing, and shielding a part of the filament for passing from the outside of the glass tubular bulb. SOLUTION: In an incandescent lamp 11, filaments 14, 15 are provided in lead-in lines 13a-13c from a base 12, to be closely sealed with a glass tubular bulb 16. The filament 14 is connected to the lead-in lines 13a, 13c, and used for running. In contrast, the filament 15 is connected to the lead-in lines 13b, 13c, and partly shielded by a light shielding plate 17 from the outside of the glass tubular bulb 16. Consequently, it is possible to prevent glare against a vehicle running on an opposite traffic lane at the time of passing each other, and simultaneously reduce the diameter of the glass tubular bulb 16 so as to reduce the material cost and an applying quantity to a reflection film. Either one of the filaments emits light by a switch. Furthermore, an infrared reflection film 19 is deposited at the outer face of the glass tubular bulb 16, so that the infrared flux from the filament 15 is reflected on the filament 15, thereby enhancing thermal conductivity and increasing the quantity of light.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to incandescent lamps, and in particular to
The present invention relates to an incandescent light bulb having a light blocking plate that blocks an illumination light beam within a predetermined range, such as a vehicle lamp.

[0002]

2. Description of the Related Art Conventionally, as an anti-glare measure for a driver of an oncoming vehicle such as an incandescent light bulb used for a headlamp for a vehicle, it is necessary to prevent the illumination light flux from being irradiated in a predetermined range. Incandescent light bulbs are known.

FIG. 5 (A) shows an incandescent light bulb 1 (for example, H4 type) used for such a vehicle headlamp, and 2 is for mounting the incandescent light bulb 1 on a housing, a reflector or the like (not shown). And a plurality of lead-in wires 5 extending from the base 2
a, 5b, 5c connected to the filament, 6 is a light-shielding plate held by the lead-in wire 5b so as to cover a part of the filament 4 (angle θ in FIG. 5C), 7 is the filament 3, 4
In addition, it is a glass tube that covers the light shielding plate 6 in a sealed state.

The filament 3 is used for traveling,
The filament 4 is used for rubbing against each other, and one of the filaments 3 and 4 emits light by operating a changeover switch (not shown) near the driver's seat of the vehicle body.

As shown in FIGS. 5 (B) and 5 (C), the light-shielding plate 6 shields a part (approximately the lower half part) of the illumination light flux emitted from the filament 4 when the filament 4 is caused to emit light. However, this light shielding provides anti-glare measures for the driver of an oncoming vehicle.

An infrared reflecting film 7 is formed on the outer surface of the glass tube 7.
a is applied. The infrared reflection film 7a reflects the infrared light flux P contained in the illumination light flux emitted from the filaments 3 and 4 to the filaments 3 and 4, and improves the thermal conductivity of the filaments 3 and 4 by this reflection. Achieve higher light intensity of illumination light flux. The tip of the glass tube 7 is light-shielding coated to prevent glare.

[0007]

By the way, in the incandescent lamp 1 configured as described above, the light shielding plate 6 that covers a part of the filament 4 is provided in the glass tube 7 in a hermetically sealed state.

Therefore, when the filaments 3 and 4 are caused to emit light, not only the infrared ray P cannot be reflected, but also the heat of the infrared ray P accompanying the emission of the filaments 3 and 4 is blocked by the light shielding plate 6. There is a problem in that the heat is absorbed and the luminous performance of the filaments 3 and 4 cannot be fully exhibited.

Further, not only is the infrared reflection film 7a at a position corresponding to the portion shielded by the light shield plate 6 wasted, but also because the light shield plate 6 is located inside the glass tube 7, the tube size is reduced. There is also a problem that the cost of the parts is large and the cost of the parts is consequently high.

The present invention has been made in view of the above circumstances, and is capable of sufficiently exhibiting the luminous performance of a filament,
An object of the present invention is to provide an incandescent light bulb that can not only increase the amount of light but also reduce the cost of parts.

[0011]

In order to achieve the object, the invention described in claim 1 is a base part having a flange for attaching a light bulb, a filament provided in the base part, and a hermetically sealing the filament. A glass tube provided on the base so as to cover the glass tube, an infrared reflection film applied to the glass tube, and an illumination light flux which is located outside the glass tube and accompanies light emission of the filament. The gist is that the light-shielding plate is provided on the base so as to shield light within the range.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of an incandescent light bulb of the present invention is applied to a vehicle headlamp (for example, H4 type) and will be described with reference to the drawings.

Referring to FIG. 1, the incandescent lamp 11 includes a base portion 1
2 and three lead wires 13a extending from the base portion 12,
Filaments 14, 15 connected to 13b, 13c
And a light-shielding plate 17 that covers a part of the filament 14 from the outside of the glass tube bulb 16.

The base 12 is integrally formed with a flange 12a for mounting the incandescent lamp 11 on a housing, a reflector or the like (not shown). Further, three terminals 18, 18 (only two shown in the drawing) are electrically connected to the lead wires 13a, 13b, 13c in a one-to-one relationship with the rear wall surface of the base 12.

The filament 14 has lead wires 13a and 13c.
Filament 1 connected between and used for traveling
Reference numeral 5 is connected between the lead-in wires 13b and 13c and is used for rubbing against each other, and one of the filaments 14 and 15 emits light by operating a changeover switch (not shown) near the driver's seat of the vehicle body.

The outer surface of the glass tube 16 is shown in FIG.
As shown in (B) and (C), an infrared reflection film 19 is applied. The infrared reflection film 19 is used for the filament 1
The infrared light flux P included in the illumination light flux emitted from the optical fiber 5 is reflected by the filament 15 (similar to the filament 14), and the thermal conductivity of the filament 15 is improved by this reflection to increase the light quantity of the illumination light flux. The tip of the glass tube 16 is light-shielding coated to prevent glare.

The light shielding plate 17 is provided with a leg portion 17b having one end 17a fixed to the base portion 12 and a light shielding portion 17d fixed to the other end 17c of the leg portion 17b.

As shown in FIGS. 2 (A) and 2 (B), one end 17a is a flat plate protruding in an L shape from a metal rod-shaped leg portion 17b, and a mounting hole formed in the base portion 12 12
Welded in the state of being inserted in b.

The other end 17d is a flat plate protruding from the leg portion 17b, as shown in FIGS.
Engagement recess 17e formed substantially in the center of the back surface of the reflecting portion 17d
Are welded in the state of being engaged with.

As shown in FIG. 1C, the reflecting portion 17d has a substantially arcuate cross-section, and the illumination light flux emitted from the filament 15 is directed toward a range of an angle θ of the lower half. Block the light flux. Since the reflecting portion 17d is located far from the filament 15, even if there is some error in the attachment position with respect to the filament 15,
It is possible to maintain the strictness of the light-shielding range more than the error in attaching the light-shielding plate 6 to the filament 4 when the light-shielding plate 6 is provided at a position close to the filament 4 as in the conventional light-shielding plate 6.

In the above structure, when the filament 15 is made to emit light by operating the changeover switch near the driver's seat of the vehicle body, a part of the illuminating light flux passes through the glass tube bulb 16 and is blocked by the light blocking portion 17d. This light shielding provides anti-glare measures for drivers of oncoming vehicles. The other part of the illumination luminous flux is transmitted through the glass tube 16 and used as it is as the illumination luminous flux.

On the other hand, the illumination light flux from the filament 15 all goes to the glass tube 16, but the infrared light flux P contained in the illumination light flux is reflected to the filament 15 by the infrared reflection film 19.

The infrared light flux P reflected by the filament 15 heats the filament 15 substantially uniformly, and this heat promotes the light emission characteristics of the filament 15 to increase the amount of light.

Further, since the light shield plate 17 is not provided inside the glass tube bulb 16 unlike the light shield plate 6 shown in the prior art, as shown in FIG. 4, the glass tube bulb 7 shown in the prior art is used. The diameter L of the glass tube 16 ′ can be made smaller than that of the glass tube 16 ′, the material cost of the glass tube 16 ′ and the coating amount of the infrared reflecting film 19 can be reduced, and a part of the infrared reflecting film 19 is provided. Never waste it. Note that, in FIG. 4, the same configurations as those shown in the above-described embodiment are denoted by the same configurations, and the description thereof will be omitted.

[0025]

As described above, in the incandescent light bulb of the present invention, the base portion having the flange for mounting the light bulb,
A filament provided in the base part, and a glass tube provided in the base part so as to cover the filament in a sealed state,
An infrared reflecting film applied to the glass tube, and a light-shielding plate that is located outside the glass tube and that is provided in the base so as to block the illumination light flux accompanying the light emission of the filament within a predetermined range Therefore, not only the luminous performance of the filament can be fully exhibited and the amount of light can be increased, but also the cost of parts can be reduced.

[Brief description of drawings]

FIG. 1 shows an incandescent light bulb of the present invention, (A) is a side view of the incandescent light bulb, (B) is an enlarged cross-sectional view of a main part as seen from a side direction,
(C) is an enlarged cross-sectional view of a main part viewed from the front direction.

FIG. 2 is an enlarged perspective view of a main part of the light-shielding plate leg portion before the one end thereof is attached, and FIG. 2B is an enlarged perspective view of the main part of the light-shielding plate leg portion after the one end is attached.

3 (A) is an enlarged perspective view of an essential part of the other end of the light shielding plate leg before attachment, and FIG. 3 (B) is an enlarged perspective view of an essential part of the light shielding plate leg after attachment at the other end. .

FIG. 4 is likewise a side view of an incandescent lamp when the diameter of the glass tube is reduced.

FIG. 5 shows a conventional incandescent light bulb, (A) is a side view of the incandescent light bulb, (B) is an enlarged cross-sectional view of a main part as seen from a side direction,
(C) is an enlarged cross-sectional view of a main part viewed from the front direction.

[Explanation of symbols]

 11 ... Incandescent light bulb 12 ... Base part 12a ... Flange 14 ... Filament 15 ... Filament 17 ... Light-shielding plate 16 ... Glass tube 19 ... Infrared reflective film

Claims (1)

[Claims] 1. A base part having a flange for mounting a light bulb,
A filament provided in the base, a glass tube provided in the base so as to cover the filament in a sealed state, an infrared reflection film applied to the glass, and an outside of the glass tube. An incandescent light bulb provided at the base so as to block the illumination light flux associated with the light emission of the filament within a predetermined range.