CN102252251B - Vehicle headlamp - Google Patents

Abstract

Headlights for vehicles. This vehicle headlamp can switch the light distribution pattern without providing a movable part, and form each light distribution pattern adapted to the respective required characteristics of the high beam and the low beam. Generates glare and improves light utilization efficiency compared to conventional ones. The vehicle headlamp (1) has: a light bulb (4), which has a first filament (41) and a second filament (42); 41) has a focal point (F1) nearby; the second reflective surface (61) of the ellipse system has a first focal point (F21) near the second filament (42) and makes the light emitted from the second filament (42) toward the first Bifocal (F22) reflection; a parabolic third reflective surface (71) having a focal point (F3) near the second focal point (F22) of the second reflective surface (61). The light bulb (4) has a light shield (43) near the first filament (41), and the light shield (43) is used for blocking light emitted from the first filament (41) to the second reflection surface (61).

Description

Vehicle Headlamps

technical field

The present invention relates to a vehicle headlamp.

Background technique

As a binocular type vehicle headlamp such as a motorcycle headlamp, a scheme capable of switching a light distribution pattern between a high beam and a low beam without providing a movable part has been proposed (for example, refer to Patent Document 1).

As shown in FIG. 7 , the vehicle headlamp 100 has: a bulb 110, which has a first light-emitting portion 111 and a second light-emitting portion 112 arranged up and down; parabolic first reflective surfaces 120, 120, which are arranged on The bottom of the bulb 110 has a focal point near the first light-emitting part 111; the second reflective surface 130, 130 of the ellipse system, which is arranged above the bulb 110, has a first focus near the second light-emitting part 112, and its length The axis extends in the left-right direction; the third reflective surface 140, 140, which takes the second focal point of the second reflective surface 130, 130 as the focus and takes the reflection direction as the direction of the optical axis Ax; and the baffle plate 150, 150, which matches It is located near the focus of the third reflective surfaces 140 and 140 to block part of the light emitted from the second reflective surface 130 to the third reflective surface 140 to form a cut-off line of the low beam beam.

And, when forming the high-beam beam, the first light-emitting part 111 on the lower side in the bulb 110 is made to emit light, the emitted light is reflected on the first reflective surfaces 120, 120 and irradiated forward, and at the same time, the light from the first light-emitting unit is illuminated. The emitted light from the portion 111 is reflected on the second reflective surfaces 130 , 130 , further reflected on the third reflective surfaces 140 , 140 and irradiated forward.

On the other hand, when the low beam is formed, the second light emitting unit 112 on the upper side in the bulb 110 is made to emit light, and the emitted light is reflected on the first reflective surface 120 to the third reflective surface 120 to the third reflector in exactly the same way as when the high beam is formed. Reflected on the surface 140 and illuminated forward.

That is, in this vehicular headlamp 100, although any light distribution pattern of the high-beam beam and the low-beam beam is formed, the same reflection process is performed, but by using the light source in the first light emitting part 111 and the second light emitting Parts 112 can be switched, and the optical path difference caused by the position difference between the first light emitting part 111 and the second light emitting part 112 can be used to switch between the high beam and the low beam without moving parts. Switches the light distribution pattern.

Patent Document 1: Japanese Patent Laid-Open No. 2008-243795

However, the above-mentioned conventional vehicle headlamp 100 has the following three problems.

First, since the same reflective surface is used to form any of the light distribution patterns, it is difficult to clarify the difference between the high beam and the low beam, and it is difficult to form each light distribution pattern individually adapted to the required characteristics.

Second, since light is reflected on all reflective surfaces when any light distribution pattern is formed, it is necessary to design an optical path with high precision. Especially when forming a low-beam beam, if the settings of the reflective surfaces and the baffle 150 are not appropriate, the light may be irradiated above the horizontal line to cause glare (glare).

Third, when any light distribution pattern is formed, the baffle plate 150 blocks a part of the light, thereby reducing the utilization rate of light.

Contents of the invention

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle headlamp capable of switching between a high beam and a low beam without providing a movable part. Light distribution patterns, wherein each light distribution pattern suitable for the characteristics required for each of the high beam and the low beam can be formed, glare is not generated when the low beam is formed, and the utilization rate of light can be improved compared with the past .

In order to solve the above problems, the invention described in technical solution 1 provides a vehicle headlamp, which is characterized in that the vehicle headlamp has:

a light bulb having a first light emitting portion and a second light emitting portion;

a parabolic first reflective surface, which has a focal point near the first light-emitting part, and reflects the light emitted from the first light-emitting part toward the front of the vehicle;

an elliptical second reflective surface, which has a first focal point near the second light-emitting part, and reflects the light emitted from the second light-emitting part toward the second focal point; and

The third reflective surface of the parabola has a focus near the second focal point of the second reflective surface, so that the light reflected by the second reflective surface is reflected toward the front of the vehicle, and the third reflective surface of the parabola is from the second focus of the second reflective surface. The direction of the bulb is obscured,

The light bulb has a light-shielding member near the first light-emitting portion, and the light-shielding member is used to block light emitted from the first light-emitting portion to the second reflective surface.

According to the present invention, when the first light-emitting part of the bulb is made to emit light, the emitted light is only reflected on the first reflective surface and irradiates forward of the vehicle, and does not enter the second reflective surface and the third reflective surface. On the other hand, when the second light emitting unit of the bulb is made to emit light, the emitted light is reflected on the second reflective surface, then reflected on the third reflective surface, and is irradiated toward the front of the vehicle. Therefore, by making the first light emitting part emit light when the low beam is formed and the second light emitting part emit light when forming the high beam, it is possible to change the light distribution pattern between the high beam and the low beam without providing a movable part. Switch between beams.

At this time, since light is incident on the second reflective surface and the third reflective surface only when the high beam is formed, the second reflective surface and the third reflective surface can be designed as reflective surfaces especially for forming the high beam, Furthermore, it is possible to form individual light distribution patterns suitable for respective required characteristics of the high beam and the low beam.

In addition, since the light is only reflected on the first reflective surface when forming the low-beam beam, and the light is not incident on the second reflective surface and the third reflective surface for forming the high-beam beam, unwanted glare will not be generated.

And, although a part of the light is blocked by the light shielding member when forming the low beam beam, it is not blocked by the light shielding member when forming the high beam beam. Ratio, the utilization rate of light can be improved.

Description of drawings

FIG. 1 is a side cross-sectional view of a vehicle headlamp according to the embodiment.

Fig. 2 is a perspective view of a light bulb.

Fig. 3 is a perspective view showing important parts of a vehicle headlamp.

Fig. 4 is a front view showing important parts of a vehicle headlamp.

FIG. 5 is a diagram showing ray trajectories when forming a light distribution pattern of a vehicle headlamp.

FIG. 6 is a diagram showing a light distribution pattern formed by a vehicle headlamp.

Fig. 7 is a perspective view showing a conventional vehicle headlamp.

Label description

1: Vehicle headlamp; 4: Bulb; 41: First filament (first light emitting part); 42: Second filament (second light emitting part); 43: Shade (shading member); 51: First reflector 61: the second reflective surface; 71: the third reflective surface; F1: the focus of the first reflective surface; F21: the first focus of the second reflective surface; F22: the second focus of the second reflective surface; F3: the second reflective surface Focus of three reflective surfaces.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 is a side sectional view of a vehicle headlamp 1 in this embodiment, FIG. 2 is a perspective view of a bulb 4 included in the vehicle headlamp, and FIGS. Perspective and front views of the parts.

In addition, in the following description, expressions of "front", "rear", "left", and "right" refer to directions of a vehicle equipped with the vehicle headlamp 1 . Similar expressions such as "front" and "front" are also the same.

As shown in FIG. 1 , a vehicular headlamp 1 has a lamp body 2 , which is opened at the front, and a light-transmitting cover 3 arranged to cover the front opening of the lamp body 2 . A light bulb 4 , a first reflector 5 , a second reflector 6 and two third reflectors 7 , 7 are accommodated in the lamp chamber formed by the lamp body 2 and the light-transmitting cover 3 .

As shown in FIG. 2 , the light bulb 4 has two light emitting parts, namely, a first filament 41 and a second filament 42 arranged side by side in the front-rear direction. Wherein, a shading cover 43 for blocking light emitted from the first filament 41 to the second reflector 6 is provided near the lower side of the first filament 41 . That is, the bulb 4 is a so-called H4-type double-filament bulb.

As shown in FIGS. 3 and 4 , the first reflector 5 is fixed at the rear of the bulb 4 and has a concave front surface, which constitutes a first reflective surface 51 . The first reflection surface 51 is a parabolic free-form surface based on a paraboloid of revolution, and has a focal point F1 near the first filament 41 . Here, “the vicinity of the first filament 41 ” refers to the vicinity of the first filament 41 including the arrangement position of the first filament 41 . Also, the expression "near" is used in the same meaning in the following description.

The second reflector 6 is arranged below the first reflector 5 and its upper surface is divided to the left and right with the lower position of the bulb 4 as the center, and each upper surface constitutes a second reflective surface 61 . Each second reflecting surface 61 is an elliptical free-form surface based on an elliptical surface of revolution having a major axis along the left-right direction, and has a first focus F21 near the second filament 42 and a second focus F22 on the left and right sides.

The third reflectors 7 and 7 are arranged on the left and right sides of the first reflector 5 and the front surfaces thereof constitute the third reflective surface 71 . The third reflective surface 71 is a parabolic free-form surface based on a paraboloid of revolution, and has a focal point F3 near the second focal point F22 of the second reflective surface 61 corresponding to the left and right second reflective surfaces 61 and 61, respectively. . In addition, the third reflective surface 71 is arranged in such a manner that the third reflective surface 71 is shielded from the direction of the bulb 4 by the first reflector 5, and the light from the first filament 41 and the second filament 42 does not directly enter the third reflective surface. reflective surface 71 .

Next, an operation for forming each light distribution pattern of the high beam and the low beam of the vehicle headlamp 1 will be described.

Fig. 5 is a diagram showing ray trajectories when forming the light distribution pattern of the vehicle headlamp 1, wherein (a) shows the ray trajectories when forming the low beam P1, and (b) shows the ray trajectories when forming the high beam. Ray traces at P2. In addition, FIG. 6 is a diagram showing a light distribution pattern formed by the vehicle headlamp 1 , in which (a) shows the low beam P1 and (b) shows the high beam P2 .

First, as shown in FIG. 5( a ), the first filament 41 of the bulb 4 is made to emit light when the low beam beam P1 is formed.

Then, the light L1 emitted from the first filament 41 to the first reflector 5 is reflected by the first reflective surface 51 and passes through the light-transmitting cover 3 to illuminate the front of the vehicle. As shown in FIG. 6( a ), this light L1 forms the entire low beam beam P1 .

In addition, since the light emitted downward from the first filament 41 is blocked by the shade 43 , it does not enter the second reflection surfaces 61 , 61 . Moreover, since the third reflective surface 71 is blocked from the direction of the bulb 4 by the first reflective plate 5 , the light from the first filament 41 does not enter the third reflective surface 71 . At this time, the cut-off line C of the low beam P1 is formed by the rear edge portion of the sunshade 43 .

On the other hand, as shown in FIG. 5( b ), the second filament 42 of the bulb 4 is made to emit light when the high beam P2 is formed.

Then, the light L2a emitted from the second filament 42 to the first reflector 5 is reflected by the first reflective surface 51 and passes through the light-transmitting cover 3 to illuminate the front of the vehicle. As shown in FIG. 6( b ), this light L2 a forms irradiation areas A1 to A3 mainly for broadly irradiating the whole of the high-beam beam P2 .

In addition, as shown in FIG. 5(b), the light L2b emitted from the second filament 42 to the second reflector 6 below is reflected by the second reflective surfaces 61, 61 to the left and right sides to focus on each second focal point F22, Then, it is reflected by the third reflective surfaces 71 of the third reflectors 7 and 7 and passes through the light-transmitting cover 3 to illuminate the front of the vehicle. As shown in FIG. 6(b), this light L2b forms an irradiation area A4 mainly for irradiating the center portion of the high beam beam P2.

According to the above vehicle headlamp 1, the light distribution pattern can be set between the low beam P1 and the high beam P2 only by switching the light emitting part between the first filament 41 and the second filament 42 of the bulb 4. to switch. That is, it is possible to switch the light distribution pattern between the high beam P2 and the low beam P1 without providing a movable part.

In addition, since light is incident on the second reflective surface 61 and the third reflective surface 71 only when the high beam P2 is formed, the second reflective surface 61 and the third reflective surface 71 can be designed specifically for forming the high beam beam P2. The reflective surface of P2 can further form individual light distribution patterns adapted to the respective required characteristics of the high beam P2 and the low beam P1.

In addition, since light is only reflected on the first reflective surface 51 when forming the low-beam beam P1, and the light is not incident on the second reflective surface 61 and the third reflective surface 71 for forming the high-beam beam P2, no adverse events will occur. The glare of hope.

In addition, although part of the light is blocked by the shade 43 when the low beam P1 is formed, it is not blocked by the shade 43 when the high beam P2 is formed, so a part of the light is blocked when any one of the light distribution patterns is formed. Compared with the conventional case, the utilization efficiency of light can be improved.

In addition, embodiments to which the present invention can be applied are not limited to the above-described embodiments, and appropriate changes can be made within a range not departing from the gist of the present invention.

Claims (1)

1. A vehicle headlamp, characterized in that, The vehicle headlamp has: a light bulb having a first light emitting portion and a second light emitting portion; a parabolic first reflective surface, which has a focal point near the first light-emitting part, and reflects the light emitted from the first light-emitting part toward the front of the vehicle; an elliptical second reflective surface, which has a first focal point near the second light-emitting part, and reflects the light emitted from the second light-emitting part toward the second focal point; and The third reflective surface of the parabola has a focus near the second focal point of the second reflective surface, so that the light reflected by the second reflective surface is reflected toward the front of the vehicle, and the third reflective surface of the parabola is from the second focus of the second reflective surface. The direction of the bulb is obscured, The light bulb has a light-shielding member near the first light-emitting portion, and the light-shielding member blocks light emitted from the first light-emitting portion to the second reflective surface, The second reflective surface is arranged below the first reflective surface, and the upper surface of the second reflective surface is divided to the left and right with the lower position of the bulb as the center, The third reflective surface is arranged on the left and right sides of the first reflective surface, and is shielded from the direction of the light bulb by the first reflective surface, When the first light-emitting part of the light bulb emits light, the light from the first light-emitting part is reflected by the first reflective surface to form a low-beam beam, When the second light emitting part of the light bulb emits light, the light from the second light emitting part is reflected by the first reflective surface, the second reflective surface and the third reflective surface to form a high beam beam.