JPS6140003Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vehicle lamp equipped with an incandescent bulb disposed laterally within a lamp chamber defined by a front lens and a housing.

Among vehicle lighting equipment, automobile tail lamps are required to be thinner, and for this reason, the front lens (or inner lens) with a Fresnel cut is required.
It is known that the filament of the incandescent bulb is located at the center of the Fresnel cut, and the incandescent bulb is attached to the housing (or back cover) with the incandescent bulb lying on its side. FIG. 1 shows a conventional vehicle lamp of this type in a side sectional view. The lamp is equipped with an incandescent bulb b inserted into a bulb holder 3 attached to the bulb holder 2. This incandescent bulb b is a commonly used one in which a filament F is built into a transparent glass bulb.

When such an incandescent bulb b is used, the temperature of the radiant heat from the filament F during lighting increases the most at point o, which is the shortest point to the front lens 1, and point p, which is the shortest point to the housing 2. Ru. In order to prevent thermal deformation at least at points o and p due to this radiant heat, distances l ₁ and h ₁ are set in accordance with the heat resistance of the synthetic resin material of the front lens 1 and the housing 2. It is set. However, since the heat resistance of the synthetic resin material is low, there is a problem in that it is not possible to make the distance l ₁ and h ₁ shorter to further reduce the thickness. Further, the effective solid angle ω of the luminous flux of the incandescent bulb b with respect to the lens 1 is: (steradian). This is an incandescent bulb b
This indicates a state in which less than half of the effective luminous flux is used. In this way, since the luminous flux of the incandescent bulb b is not effectively utilized, the bulb requires a correspondingly large amount of power consumption. This has also become an obstacle to further thinning of the device.

The present invention improves the problems of the conventional technology as described above, and makes it possible to shorten the distance from the filament F to the front lens and housing without using a particularly heat-resistant synthetic resin material. to increase the effective solid angle of the incandescent bulb to the front lens,
It is an object of the present invention to provide a vehicle lamp which can save the increased power consumption and which can be made even thinner.

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3.

The illustrated example applies the present invention to a tail lamp for an automobile, and shows a side sectional view of one of the lamp parts such as a turn signal lamp part, a tail lamp/stop lamp part, and a backup lamp part. Note that the same parts as in the conventional example shown in FIG. 1 are indicated by the same reference numerals.

FIGS. 2A to 2C show a first embodiment of the present invention. FIG. 2A shows an overall perspective view of an incandescent bulb 5 used in the present invention, and FIG. 2B shows a top view thereof. This incandescent bulb 5 includes a glass bulb 50,
Filament F ₀ built into glass bulb 50
and a base 51. The glass bulb 50 has a substantially flat shape, and has a spherical side surface 52, an upper plane 54, and a lower plane 53 parallel to the upper plane 54. A metal reflective film A is formed by vapor-depositing aluminum, nickel, chromium, etc. on a portion 55 of the glass bulb 52, and tin oxide (SnO ₂ ) is formed on the other glass bulb surfaces (the upper plane 54 and a portion of the spherical side surface 52). A transparent heat ray reflecting film B is formed using a material such as indium oxide (In ₂ O ₃ ) having good visible light transmittance and high heat ray reflectance. Note that the metal reflective film A and the heat ray reflective film B are formed on either the inner or outer surface of the glass bulb 50. Furthermore, the linear filament F ₀ is located parallel to the upper plane 54 and the lower plane 53. Such an incandescent bulb 5 is attached to the bulb holder 3 with the metal reflective film A facing the housing 2 and the heat ray reflective film B facing the lens 1, as shown in FIG. 2C.

Here, the light source luminous flux amount K of the incandescent bulb 5 and the conventional incandescent bulb b is made the same, the shortest distance l ₁ between the filament F ₀ and the lens 1, and the filament F ₀
Comparing the effective amount of light emitted to the lens 1 with the shortest distance h ₁ and the effective radius L ₁ between the lower plane 53 and the lower plane 53, [] In the case of the incandescent bulb 5 of this embodiment, the solid angle ω of the direct system; (steradian) Solid angle ω' of the reflective system curved surface 55 (dotted line range in figure C); ω' = 2π (cosθ ₁ - cosθ ₂ )・η (steradian) η: Reflectance of the metal reflective film A of the reflective system plane 53 Solid angle ω″; Therefore, the effective amount of emitted light flux F; F=K/4π・(100−ρ/100)・(ω+ω′
+ω'')τ τ: Transmittance of lens 1. [] In the case of conventional incandescent bulb b, the effective amount of emitted light flux F′; F′ = K/4π・(100−ρ/100)・ωτ Therefore, The increased effective output luminous flux △F due to the use of the incandescent bulb 5 according to the present invention is as follows: △F=F−F'=K/4π・(100−ρ/100)・
(ω′ +ω″)・τ.

In FIG. 2C, l ₁ , h ₁ , and L ₁ are temporarily set at the same distances as l ₁ , h ₁ , and L ₁ shown in FIG. 1 of the conventional example. Further, F ₀ ′ in the figure indicates a tentative focus position in the drawing regarding filament F ₀ . Further, the angle θ ₂ is the effective reflection angle on the upper side of the reflection system curved surface 55, and the angle θ ₁ is the effective reflection angle on the lower side.

In this manner, when the incandescent bulb 5 of this embodiment is replaced with the same arrangement as the conventional one shown in FIG. 1, the effective amount of emitted light flux is clearly increased.

The above comparison assumes the same arrangement relationship as in Figure 1, but in reality, the respective distances shown in Figure 2C are l ₁ > l, h ₁ > h, and L ₁ < L. Become. That is, by forming the heat ray reflecting film B on the glass bulb surface facing the lens 1 of the incandescent bulb 5, the amount of heat rays reaching the lens 1 from the filament F ₀ is reduced, so that the lens 1 and the filament
The distance l between F 0 and F ₀ can be shortened.
Further, the distance h between the lower plane 53 and the filament F ₀ is shorter than the conventional distance h ₁ , and the distance between the filament F ₀ and the housing 2 is reduced by forming the metal reflective film A on the lower plane 53. can be made extremely short. In particular, as mentioned above, the solid angle increases and the amount of light source luminous flux can be used effectively, so the distance between the lens 1 and the housing 2 can be made considerably thinner than in the conventional case, and the incandescent light is emitted by the increased amount of emitted luminous flux. It is possible to reduce the wattage of the valve 5 and save power consumption.

Figures 3A and 3B show a second embodiment of the present invention, and Figure 3A shows an incandescent bulb 7 used in the present invention.
7 is a perspective view of the entire incandescent bulb 7.
A side cross section of the lamp installed inside the lamp chamber 4 is shown. The incandescent bulb 7 includes a flat glass bulb 70 on one side, a filament F ₀ built into the glass bulb 70,
It consists of a base 71. And glass bulb 70
forms a metal reflective film A on a plane 72 and a part 73 of a spherical side surface adjacent to the plane 72, and
A heat ray reflective film B is formed on other parts. Also,
The linear filament F ₀ is positioned parallel to the plane 72 . The incandescent bulb 7 is inserted into the bulb holder 3 with the metal reflective film A of the glass bulb 70 facing the housing and the heat ray reflective film B facing the lens 1.

Therefore, in this second embodiment as well, the same effects as in the first embodiment shown in FIG. 2 can be achieved.

As described above, the vehicle lamp of the present invention includes an incandescent bulb disposed horizontally within a light chamber defined by a front lens and a housing, and the incandescent bulb is a glass bulb facing the housing. has a flat shape, and a metal reflective film is formed from the flat part to a part of the spherical side surface adjacent to the flat part, and a transparent heat ray reflective film is formed on the glass bulb surface facing the lens. , the metal reflective film increases the amount of effective emitted light flux and makes it possible to bring the distance between _the filament F ₀ and the housing closer together. This, combined with the increased solid angle and effective use of the light source luminous flux, makes it possible to make the entire lamp thinner and lower the wattage of the incandescent bulb by the increased output luminous flux. It is possible to achieve remarkable effects such as being able to save power consumption.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional vehicle lamp. FIG. 2 shows a first embodiment of the present invention; FIG. 2A is a perspective view of the entire incandescent bulb, FIG. 2B is a top view thereof, and FIG. 2C is a sectional view of a lamp with the bulb attached. Third
The figures show a second embodiment of the present invention, in which Figure A is an overall perspective view of an incandescent bulb, and Figure B is a sectional view of a lamp with the bulb attached. 1...Front lens, 2...Housing, 3...
Bulb holder, 4... lamp chamber, 5, 7... incandescent bulb, F ₀ ... filament, A... metal reflective film, B... heat ray reflective film.

Claims (1)

[Scope of utility model registration request] In a vehicle lamp equipped with an automatic bulb disposed horizontally in a light chamber defined by a front lens and a housing, the automatic bulb has a flat shape with a glass bulb facing the housing being flat. , and a metal reflective film is formed from the flat part to a part of the spherical side surface adjacent to the flat part, and a transparent heat ray reflective film is formed on the glass bulb surface facing the lens. Vehicle lighting.