Vehicular headlight

Abstract

To prevent fusion and discoloration in a control end part.SOLUTION: A vehicular headlight includes a light source for emitting light, a reflector for reflecting the light emitted from the light source, a shade for blocking part of the light reflected by the reflector, and a projection lens for projecting the light reflected by the reflector. The shade is provided with a control end part positioned on the light source side, and the control end part includes a reflection control surface subjected to reflection processing in which a focal point of the light is positioned on the surface or in the vicinity, and an inclined plane subjected to reflection processing, which continues to the edge on the light source side in the reflection control surface. The inclined plane is inclined relative to the reflection control surface so that the inclined plane is displaced downward as it is separated from the reflection control surface.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to the technical field of vehicle headlamps in which light emitted from a light source is reflected by a reflector and part of the light is blocked by a shade. [Background technology]

[0002] There is a type of vehicle headlamp in which a lamp unit having a reflector and a shade is arranged inside a lamp outer casing made up of a cover and a lamp housing (see, for example, Patent Document 1). In the vehicle headlamp described in Patent Document 1, a reflector, a shade, a projection lens, etc. are arranged inside the lamp outer casing, and light emitted from the light source is reflected by the reflector toward the shade, and part of the light is blocked by the shade, while the unblocked light is controlled and made into approximately parallel light by the projection lens, which is then irradiated to the outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-59643 Summary of the Invention [Problem to be solved by the invention]

[0004] In a vehicle headlamp having a shade such as that described in Patent Document 1, the focus of light reflected by the reflector is located on or near the surface of one end (control end) of the shade on the light source side, and therefore heat may accumulate at the control end as light enters.

[0005] In particular, when the angle of incidence of light relative to the incident surface is orthogonal or close to this angle, the illuminance tends to be high, which may cause problems such as melting or discoloration in the areas where the illuminance is high.

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle headlamp that prevents melting and discoloration at the control end. [Means for solving the problem]

[0007] The vehicle headlamp of the present invention comprises a light source that emits light, a reflector that reflects the light emitted from the light source, a shade that blocks a portion of the light reflected by the reflector, and a projection lens that projects the light reflected by the reflector, wherein the shade is provided with a control end positioned on the light source side, and the control end has a reflection control surface that has been subjected to a reflection treatment and on which the focus of light is positioned at or near the surface, and a slope that has been subjected to a reflection treatment and is continuous with the edge of the reflection control surface on the light source side, and is inclined with respect to the reflection control surface so that the slope is displaced downward as it moves away from the reflection control surface.

[0008] This reduces the angle of incidence of light on the inclined surface that is inclined relative to the reflection control surface.

[0009] Another vehicle headlamp according to the present invention comprises a light source that emits light, a reflector that reflects the light emitted from the light source, a shade that blocks a portion of the light reflected by the reflector, and a projection lens that projects the light reflected by the reflector, wherein the shade is provided with a control end portion positioned on the light source side, the control end portion having a reflection control surface that has been subjected to a reflection treatment and on which the focus of light is positioned on or near the surface, and a tip surface that faces in a direction different from the reflection control surface and through which light can be incident, and the shade is formed from a transparent material.

[0010] This allows light incident on the tip end face to be transmitted through the control end portion. [Effects of the Invention]

[0011] According to the present invention, melting and discoloration of the control end portion can be prevented. [Brief explanation of the drawings]

[0012] [Figure 1] 2 to 4 show a first embodiment of a vehicle headlamp according to the present invention, and this figure is a cross-sectional view of the vehicle headlamp. [Figure 2] FIG. [Figure 3] FIG. 10 is a cross-sectional view showing an example in which the shade is made of a transparent material. [Figure 4] FIG. 10 is a cross-sectional view of a shade showing another example of a control end portion. [Figure 5] 6 shows a second embodiment of the vehicle headlamp of the present invention, and this figure is a cross-sectional view of the vehicle headlamp. [Figure 6] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle headlamp according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0014] First, a vehicle headlamp 1 according to a first embodiment will be described (see FIGS. 1 to 4).

[0015] A vehicle headlamp 1 comprises a lamp housing 2 having an opening at the front end and a cover 3 that closes the opening of the lamp housing 2 (see Figure 1). The lamp housing 2 and the cover 3 form a lamp outer casing 4, and the internal space of the lamp outer casing 4 forms a lamp chamber 5.

[0016] A lamp unit 6 is disposed in the lamp chamber 5. The lamp unit 6 has a heat sink 7, a light source 8, a reflector 9, a shade 10, and a projection lens 11.

[0017] The heat sink 7 is made of a material with high heat dissipation properties, such as a metal material, and has a plate-shaped base portion 7a facing up and down and a plurality of heat dissipation fin portions 7b protruding downward from the base portion 7a. The heat dissipation fin portions 7b are arranged side by side in the left-right direction, for example.

[0018] For example, a light emitting diode (LED) is used as the light source 8. The light source 8 is mounted on, for example, a circuit board (not shown). The circuit board is disposed on the base portion 7a of the heat sink 7.

[0019] The reflector 9 has a lower end at the rear end attached to, for example, the rear end of the base portion 7a. The inner surface of the reflector 9 is formed as a reflective surface 9a. Light emitted from the light source 8 is reflected by the reflective surface 9a toward the shade 10.

[0020] The shade 10 is formed from a colored resin material such as polycarbonate, and has an inclined portion 12 that extends obliquely relative to the horizontal and vertical directions, and a control end portion 13 that is continuous with the rear end of the inclined portion 12 (see FIGS. 1 and 2). The inclined portion 12 is inclined so as to be displaced upward as it extends rearward, and the control end portion 13 protrudes rearward from the rear end of the inclined portion 12.

[0021] The control end portion 13 has, as its surface, a reflection control surface 13a facing upward, a slope 13b connected to the rear edge of the reflection control surface 13a, a tip surface 13c connected to the rear edge of the slope 13b, and a lower surface 13d connected to the lower edge of the tip surface 13c (see Figure 2).

[0022] The leading edge of reflection control surface 13a is continuous with the trailing edge of the upper surface of inclined portion 12, and reflection control surface 13a is subjected to reflection treatment 14 such as metal deposition. Therefore, light incident on reflection control surface 13a is reflected. The focus of light reflected by reflective surface 9a of reflector 9 is located on or near reflection control surface 13a. Because reflection control surface 13a is the surface on which or near which the focus of light reflected by reflective surface 9a is located, it is a necessary surface for ensuring appropriate optical performance of vehicle headlamp 1, and is a surface that needs to have a certain length in the longitudinal direction.

[0023] The slope 13b is inclined relative to the reflection control surface 13a so that it is displaced downward as it goes rearward. The slope 13b is subjected to a reflection treatment 14 such as metal deposition. Therefore, light incident on the slope 13b is reflected.

[0024] The tip surface 13c is formed as a surface facing rearward. The tip surface 13c and the bottom surface 13d are not subjected to a reflective treatment.

[0025] In the shade 10, the upper surface 12a of the inclined portion 12 may also be subjected to the reflective treatment 14. By subjecting the upper surface 12a to the reflective treatment 14, the upper surface 12a can be used as a reflective surface for generating, for example, overhead sign light.

[0026] The projection lens 11 is disposed on the opposite side of the shade 10 from the light source 8. At least light controlled by the control end 13 of the shade 10 is incident on the projection lens 11. The projection lens 11 has the function of controlling the incident light to be approximately parallel light and projecting it.

[0027] In the vehicle headlamp 1 configured as described above, when light is emitted from the light source 8, the emitted light is reflected by the reflecting surface 9a of the reflector 9 toward the shade 10 and is partially blocked by the shade 10. The unblocked light is controlled by the control end 13 of the shade 10 or passes near the control end 13 and enters the projection lens 11, where it is controlled to be approximately parallel light, transmitted through the cover 3, and irradiated forward.

[0028] When light is emitted from light source 8, part of the light reflected by reflecting surface 9a of reflector 9 travels as light A toward control end portion 13 in a substantially horizontal state. Light A traveling toward control end portion 13 in a substantially horizontal state is incident on slope 13b and tip end surface 13c of control end portion 13, but because slope 13b is an inclined surface, light A is incident from a direction other than a direction perpendicular to slope 13b.

[0029] In this case, if the inclined surface 13b is not formed and the control end portion 13 is shaped to have a surface M1 facing rearward as an extension of the tip surface 13c and a surface M2 facing upward as an extension of the reflection control surface 13a, as shown by the dotted line in Figure 2, light A is incident on the small-area surface M1 from a direction perpendicular (almost perpendicular), and the illuminance of the light on surface M1 is increased.

[0030] However, since the control end portion 13 of the vehicle headlamp 1 is configured to have the slope 13b instead of the surface M1 and the surface M2, the light A is incident on the slope 13b, which has a larger area than the surface M1, from a direction other than the perpendicular direction, and the amount of light per unit area is reduced, resulting in a lower illuminance of the light on the slope 13b. Therefore, even if the light A is incident on the control end portion 13, heat is unlikely to accumulate.

[0031] As described above, in the vehicle headlamp 1, the control end 13 of the shade 10 has a reflection control surface 13a that is treated with a reflection treatment 14 and on which the focus of light is positioned at or near the surface, and a slope 13b that is treated with a reflection treatment 14 and is continuous with the edge of the reflection control surface 13a on the light source 8 side, and is inclined with respect to the reflection control surface 13a so that the slope 13b is displaced downward as it moves away from the reflection control surface 13a.

[0032] Therefore, the angle of incidence of light on the inclined surface 13b, which is inclined relative to the reflection control surface 13a and has a large area, becomes smaller, and the illuminance of light on the inclined surface 13b becomes lower, making it difficult for heat to accumulate in the control end portion 13, and preventing discoloration due to melting due to heat at the control end portion 13 or peeling of the reflection treatment 14 due to heat, etc.

[0033] The control end 13 is also formed with a tip surface 13c that is continuous with the edge of the inclined surface 13b on the light source 8 side and faces in a different direction from the inclined surface 13b, for example, facing backward.

[0034] Therefore, by forming the tip surface 13c, the end of the control end portion 13 on the light source 8 side does not become a sharp-angled protrusion (protrusion T shown in Figure 2), so that it is possible to prevent melting or discoloration of the control end portion 13 while ensuring high strength of the control end portion 13.

[0035] In the vehicle headlamp 1, the shade 10 may be made of a transparent material (see FIG. 3). By making the shade 10 of a transparent material, light B that reaches the tip end surface 13c enters the inside of the control end portion 13 from the tip end surface 13c, and at least a portion of the light is transmitted through the control end portion 13. Therefore, by transmitting at least a portion of the light B through the control end portion 13, heat is less likely to accumulate in the control end portion 13, and by making the shade 10 of a transparent material, heat accumulation in the control end portion 13 can be suppressed by reducing the illuminance of light with the slope 13b.

[0036] This makes it possible to sufficiently suppress the accumulation of heat in controlling end portion 13, and therefore it is possible to reduce the area of ​​inclined surface 13b and increase the area of ​​reflection control surface 13a, thereby improving the strength of controlling end portion 13. Therefore, it is possible to sufficiently suppress the accumulation of heat in controlling end portion 13 while ensuring high strength of controlling end portion 13.

[0037] Furthermore, the shade 10 may be configured so that the rear edge of the inclined surface 13b coincides with the lower edge of the control end portion 13 (the rear edge of the lower surface 13d) and does not have the tip surface 13c (see FIG. 4). By configuring the shade 10 in this way, it is possible to maximize the area of ​​the inclined surface 13b, and the illuminance of light incident on the inclined surface 13b is sufficiently reduced, making it possible to efficiently prevent the control end portion 13 from melting or discoloring.

[0038] Next, a vehicle headlamp 1A according to a second embodiment will be described (see FIGS. 5 and 6).

[0039] The vehicle headlamp 1A described below differs from the vehicle headlamp 1 described above only in the configuration of the shade, and therefore only the parts that differ from the vehicle headlamp 1 will be described in detail, and other parts will be given the same symbols as those used for similar parts in the vehicle headlamp 1 and will not be described again.

[0040] A lamp unit 6A is disposed in the lamp chamber 5. The lamp unit 6A has a heat sink 7, a light source 8, a reflector 9, a shade 10A, and a projection lens 11.

[0041] The shade 10A is made of a transparent material and has an inclined portion 12 and a control end portion 13A. The control end portion 13A protrudes rearward from the rear end portion of the inclined portion 12.

[0042] Control end portion 13A has, as its surface, reflection control surface 13a facing upward, tip surface 13c facing backward that is continuous with the rear edge of reflection control surface 13a, and bottom surface 13d facing downward that is continuous with the lower edge of tip surface 13c. Reflection control surface 13a is subjected to reflection treatment 14, while tip surface 13c and bottom surface 13d are not subjected to reflection treatment.

[0043] In the vehicle headlamp 1A configured as described above, when light is emitted from the light source 8, the emitted light is reflected by the reflecting surface 9a of the reflector 9 toward the shade 10A, and a portion of the light is blocked by the shade 10A. The unblocked light is controlled by the control end 13A of the shade 10A, or passes near the control end 13A and enters the projection lens 11, where it is converted into approximately parallel light by the projection lens 11, transmitted through the cover 3, and emitted forward.

[0044] When light is emitted from the light source 8, part of the light reflected by the reflecting surface 9a of the reflector 9 is incident on the inside of the control end portion 13A from the tip end surface 13c, and at least part of the light is transmitted through the control end portion 13A. Therefore, heat is less likely to accumulate in the control end portion 13A.

[0045] As described above, in the vehicle headlamp 1A, The control end 13A of the shade 10A has a reflection control surface 13a that has been subjected to a reflection treatment 14 and on which the focus of light is positioned on or near the surface, and a tip surface 13c that faces in a different direction from the reflection control surface 13a and through which light can be incident, and the shade 10A is made of a transparent material.

[0046] Therefore, light incident on the tip surface 13c is transmitted through the control end portion 13A, making it difficult for heat to accumulate in the control end portion 13A, thereby preventing discoloration due to melting due to heat in the control end portion 13A or peeling of the reflective treatment 14 due to heat. [Explanation of symbols]

[0047] 1. Vehicle headlights 8 light source 9 Reflector 10 Shades 11 Projection lens 13 Control end 13a Reflection control surface 13b Slope 13c Tip surface 1A Vehicle headlights 6A Lamp Unit 10A Shade 13A Control End

Claims

1. A light source that emits light; a reflector that reflects light emitted from the light source; a shade that blocks a portion of the light reflected by the reflector; a projection lens that projects the light reflected by the reflector, The shade is provided with a control end portion positioned on the light source side, the control end portion has a reflection control surface on which a reflection treatment is applied and on which a focus of light is positioned or in the vicinity thereof, and a slope that is reflection treated and is continuous with an edge of the reflection control surface on the light source side, The inclined surface is inclined relative to the reflection control surface so as to be displaced downward as it moves away from the reflection control surface. Vehicle headlights.

2. The control end portion has a tip surface that is continuous with the edge of the inclined surface on the light source side and faces in a direction different from the inclined surface.

2. The vehicle headlamp according to claim 1.

3. the shade is made of a transparent material; Light can be incident on the control end portion from the tip end surface.

3. A vehicle headlamp according to claim 2.

4. The edge of the inclined surface on the light source side is aligned with the lower edge of the control end portion.

2. The vehicle headlamp according to claim 1.

5. A light source that emits light; a reflector that reflects light emitted from the light source; a shade that blocks a portion of the light reflected by the reflector; a projection lens that projects the light reflected by the reflector, The shade is provided with a control end portion positioned on the light source side, the control end portion has a reflection control surface on which a reflection treatment is applied and on which a focus of light is positioned or in the vicinity thereof, and a tip surface that faces in a direction different from the reflection control surface and onto which light can be incident, The shade is made of a transparent material. Vehicle headlights.

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