Vehicular headlight

Abstract

To provide a vehicular headlight that can improve energy efficiency while restraining upsizing.SOLUTION: A vehicular headlight 1 comprises: first light sources 31a, 31b, and 31c for emitting first light L1 for forming a low beam light distribution pattern PL; a second light source 32 arranged on the left side of the first light sources 31a, 31b, and 31c, and emitting second light L2 for forming a lateral light distribution pattern PS; and a projection lens 60 comprising an incidence surface 62 convexly curved on the rear side, and an emission surface 63 from which the first light L1 and the second light L2 are emitted. When the projection lens 60 is viewed from above, an optical axis LA2 of the second light L2 toward the incidence surface 62 intersects with a region on the left side of an apex 62t in the incidence surface 62 out of the incidence surface 62. The apex 62t is located on the right side of a first reference plane 64 passing through a center 65c of a line segment 65 connecting both left and right ends 62e of the incidence surface 62, and perpendicular to the line segment 65.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a vehicle headlamp. [Background technology]

[0002] Some vehicle headlights include a headlamp that emits a low beam and a cornering lamp that emits light to be irradiated to the side of the vehicle, and Patent Document 1 listed below discloses such a vehicle headlamp. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-4882 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the vehicle headlamp of the above Patent Document 1, the headlamp and the cornering lamp are separate. As a configuration of a headlamp and a cornering lamp that emit a low beam, a configuration including a light source and a projection lens through which the light emitted from the light source passes is known. In addition, a biconvex lens that is symmetrical is generally used as the projection lens. In this projection lens, in a horizontal cross section, the entrance surface is curved convexly toward the rear side, the exit surface is curved convexly toward the front side, and the central axis of the projection lens is located on a reference plane that passes through the center of a line segment connecting both the left and right ends of the entrance surface and is perpendicular to the line segment. In the vehicle headlamp of the above Patent Document 1, when the headlamp and the cornering lamp are respectively configured as described above, the projection lenses are provided separately for the headlamp and the cornering lamp. For this reason, there is a tendency for vehicle headlamps to become larger as a whole, and there is a demand for suppressing this increase in size.

[0005] In response to this request, for example, it is conceivable to share a projection lens between the headlamp and the cornering lamp. In this case, for example, the cornering lamp light source is disposed on one side in the left-right direction based on the headlamp light source. Then, it is conceivable to make light from the cornering lamp light source incident on the cornering lamp light source side of the entrance surface of the headlamp projection lens, and to make the light exit from the exit surface of the headlamp projection lens. In this case, most of the light from the cornering lamp light source is obliquely incident on the cornering lamp light source side of the entrance surface so as to approach the central axis of the projection lens. When light is incident obliquely in this way, the angle of incidence on the exit surface of the light that propagates through the projection lens and reaches the exit surface may become large. When the angle of incidence on the exit surface becomes large, the light is more likely to be totally reflected on the exit surface, and light loss may occur in the light from the cornering lamp light source. For this reason, there is a demand to reduce such light loss and improve energy efficiency.

[0006] Therefore, an object of the present invention is to provide a vehicle headlamp that can improve energy efficiency while suppressing an increase in size. [Means for solving the problem]

[0007] In order to achieve the above object, the vehicle headlamp of the present invention comprises: a first light source that emits a first light that forms a low beam light distribution pattern; a second light source that is arranged on one side in a left-right direction based on the first light source and emits a second light that forms a side light distribution pattern, at least a portion of which is located to the side of the low beam light distribution pattern; and a projection lens that is arranged forward of the first light source and the second light source and has an entrance surface that is curved convexly toward the rear in a horizontal cross section and into which the first light and the second light are incident, and an exit surface from which the first light and the second light incident from the entrance surface exit, wherein when the projection lens is viewed from above, an optical axis of the second light that advances toward the entrance surface intersects with a region of the entrance surface that is closer to the second light source than a vertex of the entrance surface, and the vertex is located on the opposite side to the second light source than a first reference plane that passes through the center of a line segment connecting both left and right ends of the entrance surface and is perpendicular to the line segment.

[0008] According to this vehicle headlamp, the first light and the second light are emitted from one projection lens, so that the size of the vehicle headlamp can be suppressed compared to a case where a projection lens for emitting the first light and a projection lens for emitting the second light are separately provided. In addition, in this vehicle headlamp, as described above, when the projection lens is viewed from above, the optical axis of the second light toward the incident surface intersects with a region of the incident surface that is closer to the second light source than the apex of the incident surface. Therefore, in this vehicle headlamp, most of the second light is incident on a region of the incident surface that is closer to the second light source than the apex of the incident surface. In general, when the apex of the incident surface moves in a direction perpendicular to the first reference surface from a state where the apex of the incident surface is located on the first reference surface, the width in the left-right direction of the region on the first reference surface side from the apex of the incident surface becomes longer. Therefore, the average angle between the region on the incident surface and the first reference surface tends to increase and approach 90°. In this vehicle headlamp, the apex of the incident surface is located on the opposite side to the second light source side from the first reference surface. Therefore, according to this vehicle headlamp, the angle of incidence of the second light on the incident surface is larger than when the apex of the incident surface is located on the first reference surface, and the angle of refraction of the second light on the incident surface is also larger. Therefore, according to this vehicle headlamp, the propagation direction of the second light from the incident surface toward the exit surface can be made to follow the first reference surface, compared to the above case. In general, since the first reference surface extends in the front-rear direction, when the propagation direction of the light toward the exit surface is made to follow the first reference surface, the angle of incidence of the light on the exit surface tends to be smaller. Therefore, according to this vehicle headlamp, the angle of incidence of the second light on the exit surface can be made smaller than when the above case, and the second light is less likely to be totally reflected on the exit surface, thereby improving energy efficiency.

[0009] The exit surface may be curved convexly toward the forward side in a horizontal cross section, and at least a portion of the side light distribution pattern may be located on the opposite side to the one side in the low beam light distribution pattern, and when the projection lens is viewed from above, a half line extending from the center of a line segment connecting the left and right ends of the exit surface to an elbow point in the cutoff line of the low beam light distribution pattern may be inclined with respect to the second reference plane so as to move forward away from a second reference plane that passes through the center of the line segment connecting the left and right ends of the exit surface and is perpendicular to the line segment toward the one side.

[0010] In this vehicle headlamp, the direction of the emission surface can be closer to the direction from the center of the line segment connecting the left and right ends toward the side light distribution pattern than when the half line is located on the second reference plane. Therefore, with this vehicle headlamp, the incident angle of the second light on the emission surface can be made smaller than in the above case, making it difficult for the second light to be totally reflected on the emission surface, and improving energy efficiency.

[0011] The exit surface may be curved in a convex shape toward the front side in a horizontal cross section, and a curvature of the exit surface in the left-right direction may become smaller as the exit surface approaches an outer edge thereof.

[0012] The vertex of the entrance surface may be located on the optical axis of the projection lens. Effect of the Invention

[0013] As described above, according to the present invention, a vehicle headlamp that can improve energy efficiency while suppressing an increase in size can be provided. [Brief description of the drawings]

[0014] [Figure 1] 1 is a plan view showing a vehicle headlamp according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a vertical cross-sectional view of the lighting unit. [Figure 4] FIG. [Diagram 5]FIG. 2 is a plan view of the lamp unit with the heat sink and the light source unit removed. [Figure 6] FIG. 2 is a horizontal cross-sectional view of the projection lens. [Figure 7] 6 is an enlarged view of a portion including a projection lens in FIG. 5. FIG. [Figure 8] 4 is an enlarged view of a part of FIG. 3, showing an example of optical paths of a first light emitted from a first light source and a second light emitted from a second light source. FIG. [Figure 9] FIG. 5 is a diagram showing an example of optical paths of a first light emitted from a first light source and a second light emitted from a second light source. [Figure 10] 1A and 1B are diagrams illustrating a low beam light distribution pattern and a side light distribution pattern. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, a preferred embodiment of the vehicle headlamp according to the present invention will be described in detail with reference to the drawings. The embodiments exemplified below are intended to facilitate understanding of the present invention, and are not intended to limit the present invention. The present invention can be modified and improved without departing from the spirit of the present invention. In addition, the present invention may be appropriately combined with the components in the embodiments exemplified below. In addition, in the drawings referred to below, the dimensions of each member may be changed in order to facilitate understanding. In addition, in the drawings, for ease of viewing, reference symbols are assigned to only some of the similar components, and some reference symbols may be omitted.

[0016] FIG. 1 is a plan view showing a vehicle headlamp according to an embodiment of the present invention. Vehicle headlamp is generally provided on each of the left and right sides of the front of a vehicle. In this specification, "right" means the right side in the forward direction of the vehicle, and "left" means the left side in the forward direction of the vehicle. The left and right vehicle headlamp have roughly the same configuration. Therefore, the following will explain one of the vehicle headlamp.

[0017] The vehicle headlamp 1 of this embodiment mainly comprises a housing 10 and a lamp unit LU. In Fig. 1, the housing 10 is shown in horizontal cross section. The housing 10 has a lamp housing 11 and a light-transmitting front cover 12. The front of the lamp housing 11 is open, and the front cover 12 is fixed to the lamp housing 11 so as to close the opening. The lamp unit LU is housed in the space formed by the lamp housing 11 and the front cover 12.

[0018] Fig. 2 is an exploded perspective view of the lamp unit LU, which is an exploded perspective view of the lamp unit LU as seen from diagonally above the front. Fig. 3 is a vertical cross-sectional view of the lamp unit LU, which is a vertical cross-sectional view along the optical axis of a projection lens 60 described later. As shown in Figs. 2 and 3, the lamp unit LU of this embodiment mainly includes a heat sink 20, a light source section 30, a reflector 40, a projection lens 60, a shade 70, a slope section 75, a holder 80, a first sub-reflector 90, and a second sub-reflector 88.

[0019] As shown in FIG. 1 and FIG. 2, the heat sink 20 of this embodiment includes a main part 21, a pair of side wall parts 22, a rear wall part 23, and fins 24. The main part 21 is a plate-like member extending in a generally horizontal direction, the side wall part 22 is a plate-like member extending downward from both left and right edges of the main part 21, and the rear wall part 23 is a plate-like member extending downward from the rear edge of the main part 21. In this embodiment, the rear wall part 23 is divided into two parts. The main part 21 and the side wall part 22 are integral, and the main part 21 and the rear wall part 23 are integral. The two parts being integral means that a connection part connecting the two parts is not formed. In this embodiment, the main part 21, the side wall part 22, and the rear wall part 23 are formed by bending a metal plate.

[0020] The main portion 21 has a first through hole 2h1, a second through hole 2h2, two screw holes 2h3, and two pin holes 2h4 that penetrate in the thickness direction. In this embodiment, the first through hole 2h1 is long in the left-right direction. The front edge of the first through hole 2h1 is linear and inclined toward the rear from the left side to the right side, and the rear edge is arc-shaped and curved convexly toward the rear side.

[0021] The fin 24 in this embodiment is a plate-like member that extends from a surface that defines a front edge of the surfaces that define the first through hole 2h1 to above the main part 21. Note that in the up-down direction, a portion of the first through hole 2h1 does not overlap with the fin 24. In this embodiment, the fin 24 is formed by punching and bending the plate-like main part 21.

[0022] The heat sink 20 may be made of a metal such as aluminum.

[0023] Fig. 4 is a plan view of the light source unit 30. As shown in Figs. 2 and 4, the light source unit 30 of this embodiment has three first light sources 31a, 31b, and 31c, a second light source 32, and a circuit board 33. The circuit board 33 is placed on the lower surface of the main part 21 in the heat sink 20. The circuit board 33 has a through hole 3h1 at a position corresponding to the screw hole 2h3 of the main part 21, and has a through hole 3h2 at a position corresponding to the pin hole 2h4.

[0024] The first light source 31a, 31b, 31c and the second light source 32 are mounted on the lower surface of the circuit board 33, and emit white light when power is supplied from the circuit board 33. In this embodiment, the first light source 31a, 31b, 31c and the second light source 32 are LEDs (Light Emitting Diodes) and emit light downward. The first light source 31b is disposed to the left and forward of the first light source 31a, and the first light source 31c is disposed to the left and forward of the first light source 31b. The first light sources 31a, 31b, 31c are light sources for low beam and emit first light that forms a light distribution pattern of the low beam. The second light source 32 is disposed to the left and forward of the first light source 31c, and emits second light that forms a lateral light distribution pattern at least a part of which is located to the side of the light distribution pattern of the low beam. In this embodiment, the first light sources 31a, 31b, 31c and the second light source 32 are arranged along an arc that curves convexly toward the rear side. The second light source 32 only needs to be disposed on the left side of the first light sources 31a, 31b, and 31c, and there is no limitation on the type and number of the first light sources 31a, 31b, and 31c and the second light sources 32. The light distribution pattern is, for example, a light pattern drawn by light irradiated onto a vertical surface located in front of the vehicle, and includes the light intensity distribution in addition to the outer shape of the light.

[0025] FIG. 5 is a plan view of the lamp unit LU with the heat sink 20 and the light source section 30 removed, and is a view of the lamp unit LU in this state seen from above. In FIG. 5, the light source section 30 is indicated by a broken line. As shown in FIG. 3 and FIG. 5, the reflector 40 of this embodiment includes a fixing section 41 and a main body section 50. The fixing section 41 of this embodiment is a plate-like member extending in the horizontal direction. On the upper surface of the fixing section 41, bosses 42 protruding upward at positions corresponding to the two screw holes 2h3 of the main section 21, and positioning pins 43 protruding upward at positions corresponding to the two pin holes 2h4 of the main section 21 are provided integrally with the fixing section 41. Each boss 42 has a screw hole 42h provided along the boss 42 from the tip surface. In addition, four protrusions 44 are provided integrally with the fixing section 41 on the upper surface of the fixing section 41. The tip surfaces of the four protrusions 44 are located on approximately the same horizontal plane, one of the protrusions 44 is rod-shaped and long in the left-right direction, and the other three protrusions 44 are circular.

[0026] 2, the boss 42 is inserted into the through hole 3h1 of the circuit board 33, the positioning pin 43 is inserted into the through hole 3h2 of the circuit board 33 and the pin hole 2h4 in the main part 21 of the heat sink 20, and the lower surface of the circuit board 33 abuts against the tip surfaces of the four protrusions 44. Then, the screw 95 is inserted into the screw hole 2h3 of the main part 21 and fastened into the screw hole 42h, thereby fixing the main part 21 to the fixed part 41. Also, the circuit board 33 is sandwiched between the main part 21 and the four protrusions 44 and fixed to the fixed part 41. In this way, the heat sink 20 and the light source part 30 are fixed to the fixed part 41.

[0027] Returning to FIG. 3 and FIG. 5, the main body 50 of this embodiment is a plate-like member extending obliquely downward from the front end of the fixing part 41, and is located below the light source part 30. The upper surface of the main body 50 includes three first reflecting surfaces 51a, 51b, and 51c and a second reflecting surface 52. The first reflecting surface 51a is a curved surface located below the first light source 31a and curved concavely downward, and reflects the first light from the first light source 31a forward. The first reflecting surface 51b is a curved surface located below the first light source 31b and curved concavely downward, and reflects the first light from the first light source 31b forward. The first reflecting surface 51c is a curved surface located below the first light source 31c and curved concavely downward, and reflects the first light from the first light source 31c forward. The second reflecting surface 52 is a curved surface that is located below the second light source 32 and curves concavely downward, and reflects the second light from the second light source 32 forward. Since the second light source 32 is located to the left of the first light sources 31a, 31b, and 31c, the second reflecting surface 52 is also located to the left of the first light sources 31a, 31b, and 31c.

[0028] Therefore, the portion of the reflector 40 including the first reflecting surfaces 51a, 51b, and 51c is the first reflector 40a that reflects the first light forward, and the portion of the reflector 40 including the second reflecting surface 52 is the second reflector 40b that reflects the second light forward, and the second reflector 40b is located to the left of the first light sources 31a, 31b, and 31c. In other words, the reflector 40 includes the first reflector 40a and the second reflector 40b, and the second reflector 40b is located to the left of the first light sources 31a, 31b, and 31c. It can also be understood that the first reflector 40a and the second reflector 40b are integral.

[0029] In this embodiment, the first reflecting surface 51a is based on a spheroidal surface, and the first focal point of the spheroidal surface is located near the first light source 31a or the first light source 31a. The first reflecting surface 51b is based on two spheroidal surfaces arranged side by side, and is a curved surface connecting the two spheroidal surfaces, and each first focal point is located near the first light source 31b or the first light source 31b. The first reflecting surface 51c is based on two spheroidal surfaces arranged side by side, similar to the first reflecting surface 51b, and each first focal point is located near the first light source 31c or the first light source 31c. The second reflecting surface 52 is based on two spheroidal surfaces arranged side by side, similar to the first reflecting surface 51b, and each first focal point is located near the second light source 32 or the second light source 32. The first reflecting surfaces 51a, 51b, 51c and the second reflecting surface 52 are not limited. For example, the first reflecting surface 51a may be a curved surface based on two ellipsoidal surfaces arranged side by side, similar to the first reflecting surface 51b, and the first reflecting surfaces 51b, 51c and the second reflecting surface 52 may be a curved surface based on one ellipsoidal surface, similar to the first reflecting surface 51a.

[0030] In this embodiment, the three first reflecting surfaces 51a, 51b, 51c and the second reflecting surface 52 are arranged along an arc that curves convexly toward the rear side, similar to the first light sources 31a, 31b, 31c and the second light source 32. A part of the left side of the outer edge of the first reflecting surface 51a also serves as a part of the right side of the outer edge of the first reflecting surface 51b. Therefore, the first reflecting surface 51a and the first reflecting surface 51b can be brought closer to each other than when a part of the outer edge of the first reflecting surface 51a does not also serve as a part of the outer edge of the first reflecting surface 51b. A part of the left side of the outer edge of the first reflecting surface 51b also serves as a part of the right side of the outer edge of the first reflecting surface 51c, and a part of the left side of the outer edge of the first reflecting surface 51c also serves as a part of the right side of the outer edge of the second reflecting surface 52. Therefore, the first reflecting surface 51b and the first reflecting surface 51c can be brought closer to each other than when a part of the outer edge of the first reflecting surface 51b does not also serve as a part of the outer edge of the first reflecting surface 51c, and the first reflecting surface 51c and the second reflecting surface 52 can be brought closer to each other than when a part of the outer edge of the first reflecting surface 51c does not also serve as a part of the outer edge of the second reflecting surface 52. Note that a part of the outer edge of the first reflecting surface 51a does not have to also serve as a part of the outer edge of the first reflecting surface 51b, a part of the outer edge of the first reflecting surface 51b does not have to also serve as a part of the outer edge of the first reflecting surface 51c, and a part of the outer edge of the first reflecting surface 51c does not have to also serve as a part of the outer edge of the second reflecting surface 52.

[0031] 1, in this embodiment, the first reflection surfaces 51a, 51b, 51c and the second reflection surface 52 overlap with the first through hole 2h1 in the main portion 21 of the heat sink 20 in the vertical direction and are exposed to the outside. Note that the first reflection surfaces 51a, 51b, 51c and the second reflection surface 52 do not necessarily have to overlap with the first through hole 2h1.

[0032] Fig. 6 is a horizontal cross-sectional view of the projection lens 60. As shown in Figs. 2, 3, 5 and 6, the projection lens 60 of this embodiment has a lens body 61 that changes the divergence angle of the light that passes through it, and a flange-shaped fixing portion 69 provided on the outer periphery of the lens body 61, and is disposed in front of the reflector 40.

[0033] In this embodiment, the lens body 61 is a biconvex aspheric lens having an outer shape of a generally rectangular shape elongated in the left-right direction, and the entrance surface 62 located on the rear side is curved convexly toward the rear side in vertical and horizontal cross sections, and the exit surface 63 located on the front side is curved convexly toward the front side in vertical and horizontal cross sections. Both left and right ends 62e of the entrance surface 62 are located forward of the rear surface of the fixing part 69. The first light from the first light sources 31a, 31b, and 31c reflected by the first reflecting surfaces 51a, 51b, and 51c and the second light from the second light source 32 reflected by the second reflecting surface 52 are incident on the entrance surface 62, and the first light and the second light incident from the entrance surface 62 are emitted from the exit surface 63. That is, the lens body 61 includes a first lens body through which the first light from the first light sources 31a, 31b, and 31c reflected by the first reflector 40a passes and changes the divergence angle of the first light, and a second lens body through which the second light from the second light source 32 reflected by the second reflector 40b passes and changes the divergence angle of the second light. It can also be understood that the first lens body and the second lens body are integrated. For this reason, it can be understood that the projection lens 60 is configured by integrating the first projection lens 60a through which the first light L1 reflected by the first reflector 40a passes and the second projection lens 60b through which the second light L2 reflected by the second reflector 40b passes.

[0034] FIG. 7 is an enlarged view of a portion including the projection lens 60 in FIG. 6. Note that in FIG. 7, the lens holding portion 81 of the holder 80, which will be described later, is omitted. In this embodiment, as shown in FIG. 7, when the projection lens 60 is viewed from above, the optical axis LA2 of the second light reflected by the second reflecting surface 52 and directed toward the incident surface 62 is located on the left side of the first reference surface 64, which is the second light source 32 side, and approaches the first reference surface 64 as it approaches the incident surface. The first reference surface 64 is a surface that passes through the center 65c of a line segment 65 connecting both the left and right ends 62e, 62e of the incident surface 62 and is perpendicular to the line segment 65. The optical axis LA2 intersects with a region of the incident surface 62 to the left of the vertex 62t of the incident surface 62. The vertex 62t is located to the right of the first reference surface 64.

[0035] In this embodiment, a half line 67 extending from a center 66c of a line segment 66 connecting both the left and right ends 63e, 63e of the exit surface 63 toward an elbow point in the cutoff line of the low beam light distribution pattern is inclined relative to the second reference plane 68 so as to move away from the second reference plane 68 to the left as it moves forward. The second reference plane 68 is a plane that passes through the center 66c of the line segment 66 and is perpendicular to the line segment 66. The relationship between the half line 67 and the second reference plane 68 is not limited. For example, the half line 67 may be located on the second reference plane 68.

[0036] In addition, in this embodiment, the curvature of the emission surface 63 in the left-right direction becomes smaller as it approaches the outer edge of the emission surface 63. However, the curvature of the emission surface 63 is not limited. For example, the curvature of the emission surface 63 in the left-right direction may be constant.

[0037] In this embodiment, the optical axis 60c of the projection lens 60 is approximately parallel to the half line 67, and the vertex 62t of the incident surface 62 is located on this optical axis 60c. The focal point on the rear side of the projection lens 60 is located at the second focal point of the elliptical curved surface of the first reflecting surface 51a or in the vicinity of the second focal point. The optical axis 60c may be non-parallel to the half line 67, and the vertex 62t may not be located on the optical axis 60c. The focal point on the rear side of the projection lens 60 is not limited. In FIG. 5 and FIG. 7, the position of the optical axis 60c is slightly shifted in the left-right direction to prevent the figures from becoming complicated.

[0038] In this embodiment, the optical axis LA1a of the first light reflected by the first reflecting surface 51a toward the incident surface 62 generally coincides with the optical axis 60c and passes through the vertex 62t. The optical axis LA1b of the first light reflected by the first reflecting surface 51b toward the incident surface 62 is located to the right of the first reference surface 64, and the optical axis LA1c of the first light reflected by the first reflecting surface 51c toward the incident surface 62 is located to the left of the first reference surface 64 and approaches the first reference surface 64 as it approaches the incident surface 62. These optical axes LA1b and LA1c intersect with a region of the incident surface 62 to the left of the vertex 62t on the incident surface 62. The relationship between the optical axes LA1a, LA1b, and LA1c and the incident surface 62 is not limited. For example, the optical axis LA1a does not have to coincide with the optical axis 60c.

[0039] In this embodiment, the fixed portion 69 has an outer shape that is generally rectangular and elongated in the left-right direction, and has two pin holes 69h. Examples of materials that form the projection lens 60 include resin and glass, and in this embodiment, the lens body 61 and the fixed portion 69 are integrated.

[0040] As shown in FIG. 3 and FIG. 5, the shade 70 of this embodiment is a plate-like member disposed between the reflector 40 and the projection lens 60 and extending in the front-rear and left-right directions. The shade 70 is located above the front end of the reflector 40 and below the main part 21 of the heat sink 20, and is curved along an arc that is curved convexly rearward. The upper surface 70s of the shade 70 is inclined upward toward the front. In addition, the front edge 71 of the upper surface 70s has a step portion 72 that is inclined upward from the right side to the left side, and the portion of the front edge 71 other than the step portion 72 is generally parallel to the horizontal direction. The second focus of the elliptical curved surface of the first reflecting surface 51a is located at or near the step portion 72 at the front edge 71. Further, the second focal points of the elliptical surfaces of the first reflecting surfaces 51b, 51c and the second reflecting surface 52 are located in the area to the left of the step portion 72 on the leading edge 71 or in the vicinity of the area. Note that the second focal point of the elliptical surface of the first reflecting surface 51c is located to the left of the second focal point of the first reflecting surface 51b, and the second focal point of the elliptical surface of the second reflecting surface 52 is located to the left of the second focal point of the first reflecting surface 51c.

[0041] An upper surface 70s of the shade 70 is irradiated with a part of the first light from the first light sources 31a, 31b, 31c reflected by the first reflecting surfaces 51a, 51b, 51c and a part of the second light from the second light source 32 reflected by the second reflecting surface 52, and blocks these lights. That is, the shade 70 includes a first shade 70a that blocks a part of the first light from the first light sources 31a, 31b, 31c reflected by the first reflector 40a, and a second shade 70b that blocks a part of the second light from the second light source 32 reflected by the second reflector 40b. It can also be understood that the first shade 70a and the second shade 70b are integral with each other.

[0042] In this embodiment, on the upper surface 70s of the shade 70, an area irradiated with the first light from the first light source 31a overlaps with an area irradiated with the first light from the first light source 31b, an area irradiated with the first light from the first light source 31b overlaps with an area irradiated with the first light from the first light source 31c, and an area irradiated with the first light from the first light source 31a overlaps with an area irradiated with the second light from the second light source 32. In the shade 70 of this embodiment, the upper surface 70s is a reflective surface that reflects light, and the upper surface 70s reflects a part of the first light and a part of the second light to block a part of the first light and a part of the second light.

[0043] The slope portion 75 in this embodiment is a plate-like member that connects the reflector 40 and the shade 70. The slope portion 75 extends obliquely upward toward the front from the front end of the reflector 40 and connects to the rear end of the shade 70. Therefore, an upper surface 76 of the slope portion 75 is inclined upward toward the front. In this embodiment, the upper surface 76 is a reflective surface that reflects another part of the first light from the first light sources 31a, 31b, and 31c toward a first sub-reflector 90 described later.

[0044] As described above, the reflector 40 includes the first reflector 40a and the second reflector 40b, and the shade 70 includes the first shade 70a and the second shade 70b. Therefore, the slope portion 75 includes a first slope portion 75a that connects the first reflector 40a and the first shade 70a, and a second slope portion 75b that connects the second reflector 40b and the second shade 70b. It can also be understood that the first slope portion 75a and the second slope portion 75b are integral with each other.

[0045] As shown in FIGS. 2, 3 and 5, the holder 80 of this embodiment has a lens holding portion 81 and a connection portion 85, and holds the projection lens 60.

[0046] The lens holding portion 81 of this embodiment is a plate-like member disposed forward of the shade 70 and extending in the up-down and left-right directions. The lens holding portion 81 is generally rectangular and elongated in the left-right direction. The lens holding portion 81 has a through hole 81h penetrating in the thickness direction, and the through hole 81h is rectangular corresponding to the lens body portion 61 of the projection lens 60. On the front surface of the lens holding portion 81, a pin 82 protruding forward is provided integrally with the lens holding portion 81 at a position corresponding to each of the two pin holes 69h of the fixing portion 69 of the projection lens 60. In addition, around the through hole 81h on the front surface of the lens holding portion 81, a plurality of pedestal portions 83 protruding forward are provided integrally with the lens holding portion 81. The pin 82 is inserted into the pin hole 69h of the fixing portion 69 of the projection lens 60, and the fixing portion 69 abuts against the pedestal portion 83 from the front side. The fixing portion 69 is fixed to the base portion 83 by, for example, laser welding, and the projection lens 60 is supported by the holder 80. With the projection lens 60 supported by the holder 80, a portion of the lens main body 61 rearward of the fixing portion 69 is inserted into the through-hole 81h of the lens holding portion 81.

[0047] The connection portion 85 of this embodiment is a plate-like member that connects the lens holding portion 81 and the shade 70, and has a lower plate portion 86 that extends downward and rearward from a through hole 81h on the rear surface of the lens holding portion 81, and a rear plate portion 87 that extends upward and diagonally rearward from the rear end of the lower plate portion 86 and is connected to the front end of the shade 70. In this embodiment, the portion of the rear plate portion 87 that is located in front of the first reflection surface 51a of the reflector 40 and connects to a portion of the shade 70 that blocks the first light from the first light source 31a is a second sub-reflector 88 that is curved concavely toward the rear. For this reason, the second sub-reflector 88 is located forward and below the shade 70, and a front surface 89 of the second sub-reflector 88 is a curved surface that is curved concavely toward the rear. This front surface 89 reflects light reflected by a first sub-reflector 90 described later toward the projection lens 60.

[0048] The first sub-reflector 90 of this embodiment is a plate-like member located in front of the first light source 31a, 31b, 31c and the second light source 32 and above the shade 70, and is disposed on the lower surface of the main portion 21 of the heat sink 20. In this embodiment, the lower surface 91 of the first sub-reflector 90 reflects a part of the first light reflected by the first reflecting surfaces 51a, 51b and the slope portion 75 of the reflector 40 toward the second sub-reflector 88. Note that the first sub-reflector 90 only needs to reflect a part of the first light reflected by at least one of the first reflecting surfaces 51a, 51b, 51c toward the second sub-reflector 88, and may, for example, reflect only a part of the first light reflected by the first reflecting surface 51a toward the second sub-reflector 88. Examples of materials constituting the first sub-reflector 90 include metals such as aluminum.

[0049] In this embodiment, as described above, the reflector 40 and the shade 70 are connected via the slope portion 75, the holder 80 is connected to the shade 70, and a part of the holder 80 is the second sub-reflector 88. The reflector 40, the shade 70, the slope portion 75, and the holder 80 are integral, and as shown in FIG. 3, these members constitute one unit member UP. In this embodiment, the unit member UP is composed of a main body portion UP1 and a light reflecting film UP2. The light reflecting film UP2 is provided on the upper surface of a portion of the main body portion UP1 that is composed of the reflector 40, the shade 70, the slope portion 75, and the connection portion 85 of the holder 80. Examples of materials that constitute the main body portion UP1 include resin, and examples of the light reflecting film UP2 include a metal vapor deposition film such as aluminum. In this embodiment, the reflector 40, the shade 70, the slope portion 75, and the holder 80 are continuous in a vertical cross section along the optical axis 60c of the projection lens 60.

[0050] Next, the operation of the vehicle headlamp 1 of this embodiment will be described. Fig. 8 is a diagram showing an example of the optical paths of the first light emitted from the first light sources 31a, 31b, and 31c and the second light emitted from the second light source 32, by enlarging a part of Fig. 3. Fig. 9 is a diagram showing an example of the optical paths of the first light emitted from the first light sources 31a, 31b, and 31c and the second light emitted from the second light source 32 in Fig. 5. Note that the reflection angles and refraction angles of the light shown in Figs. 8 and 9 may be slightly different.

[0051] In the vehicle headlamp 1 of this embodiment, a low beam light distribution pattern is formed by emitting a first light L1 downward from the first light sources 31a, 31b, and 31c, and a lateral light distribution pattern is formed by emitting a second light L2 downward from the second light source 32.

[0052] First, the formation of the low beam light distribution pattern will be described. As shown in Fig. 8 and Fig. 9, the first light L1 from the first light sources 31a, 31b, and 31c is mainly reflected forward by the first reflecting surfaces 51a, 51b, and 51c of the reflector 40. A part of the first light L1 reflected by the first reflecting surfaces 51a, 51b, and 51c is directly incident on the incident surface 62 of the projection lens 60 without being blocked by the shade 70, another part is irradiated on the upper surface of the shade 70, and another part is irradiated on the lower surface 91 of the first sub-reflector 90. The first light L1 directly incident on the incident surface 62 is emitted from the exit surface 63. The area on the upper surface 70s of the shade 70 where the first light L1 is irradiated is in contact with a portion including the step portion 72 on the front edge 71 of the upper surface 70s. The upper surface 70s of the shade 70 reflects the first light L1 so as not to enter the projection lens 60, blocking the first light L1. Therefore, a cutoff line is formed in the light distribution pattern formed by the first light L1, and the light distribution pattern becomes a low beam light distribution pattern. That is, the shade 70 forms a cutoff line of the low beam light distribution pattern, and the cutoff line of the low beam light distribution pattern has a shape corresponding to the front edge 71. In this way, the low beam light distribution pattern is formed by the first light L1, and light having this low beam light distribution pattern is emitted from the lamp unit LU and irradiated forward through the front cover 12. As described above, the rear focal point of the projection lens 60 is located at or near the front edge 71 of the upper surface of the shade 70, so that the low beam light distribution pattern projected forward is a light distribution pattern inverted by the projection lens 60.

[0053] The first light L1 irradiated to the lower surface 91 of the first sub-reflector 90 is reflected toward the front surface 89 of the second sub-reflector 88, and the front surface 89 reflects the first light L1 reflected by the lower surface 91 of the first sub-reflector 90 toward the projection lens 60. The first light L1 reflected by the front surface 89 passes through the projection lens 60 and is irradiated forward, and the light distribution pattern formed by the first light L1 is added to the low beam light distribution pattern. The second sub-reflector 88 is located forward and below the shade 70, and the area irradiated by the first light L1 on the front surface 89 of the second sub-reflector 88 is separated from and below the front edge 71 of the upper surface 70s of the shade 70. Therefore, the light distribution pattern formed by the first light L1 reflected by the front surface 89 of the second sub-reflector 88 becomes a light distribution pattern for an overhead sign located above the low beam light distribution pattern.

[0054] FIG. 10 is a diagram showing a low beam light distribution pattern and a side light distribution pattern in this embodiment. In FIG. 10, S indicates a horizontal line, V indicates a vertical line passing through the center of the vehicle in the left-right direction, and a low beam light distribution pattern PL projected on a virtual vertical screen located 25 m ahead of the vehicle is shown by a thick line. The first reflecting surfaces 51a, 51b, and 51c of the reflector 40 and the shade 70 are shaped so that the light distribution pattern of the first light L1 becomes such a low beam light distribution pattern PL. The low beam light distribution pattern PL of this embodiment is for countries and regions where vehicles drive on the left side. In addition, the cutoff line CL of the low beam light distribution pattern PL corresponds to the shape of the front edge 71 of the upper surface of the shade 70, and the cutoff line CL has a step portion CLa corresponding to the step portion 72. The step portion CLa is composed of a line that slopes upward toward the left side from an elbow point EP located below the horizontal line S and on or near the vertical line V. The cutoff line CL extends generally horizontally except for the step portion CLa. In addition, a light distribution pattern OH for an overhead sign formed by the first light L1 reflected by the front surface 89 of the second sub-reflector 88 is added to the low beam light distribution pattern PL. The light distribution pattern OH for an overhead sign is located above the low beam light distribution pattern PL and is separated from the cutoff line CL.

[0055] Next, the formation of the lateral light distribution pattern will be described. As shown in Figs. 8 and 9, the second light L2 from the second light source 32 is mainly reflected forward by the second reflecting surface 52 of the reflector 40. A part of the first light L1 reflected by the second reflecting surface 52 is not blocked by the shade 70 and directly enters the entrance surface 62 of the projection lens 60, and the other part is irradiated onto the upper surface of the shade 70. The optical axis LA2 of the second light L2 traveling from the second reflecting surface 52 toward the entrance surface 62 intersects with an area on the entrance surface 62 that is closer to the second light source 32 than the vertex 62t, so that most of the second light L2 enters that area. The second light L2 that directly enters the entrance surface 62 exits from the exit surface 63. The area on the upper surface 70s of the shade 70 where the second light L2 is irradiated is in contact with a portion on the left side of the step portion 72 at the front edge 71 of the upper surface 70s. The upper surface 70s of the shade 70 reflects the second light L2 so as not to enter the projection lens 60, blocking the second light L2. Therefore, the upper edge of the light distribution pattern formed by the second light L2 has a shape corresponding to the front edge 71. In this way, a light distribution pattern whose upper edge has a shape corresponding to the front edge 71 is formed by the second light L2, and light having this light distribution pattern is emitted from the lamp unit LU and irradiated forward through the front cover 12. Here, the optical axis LA2 of the second light L2 is located to the left of the optical axes LA1a, LA1b, and LA1c of the first light L1 that are directed from the first reflecting surfaces 51a, 51b, and 51c toward the entrance surface 62. Therefore, at least a part of the light distribution pattern formed by the second light L2 is located to the right of the low beam light distribution pattern PL. In this way, as shown in FIG. 10, the second light L2 forms a side light distribution pattern PS, at least a part of which is located to the right of the low beam light distribution pattern. As described above, the region of the upper surface of the shade 70 where the first light L1 from the first light source 31c is irradiated and the region of the upper surface 70s of the shade 70 where the second light L2 is irradiated overlap, and the portion of the front edge 71 of the upper surface 70s of the shade 70 other than the step portion 72 is generally parallel to the horizontal direction. Therefore, the upper edge UE of the lateral light distribution pattern PS and the portion to the right of the elbow point EP in the cutoff line CL generally coincide with each other, but they do not have to coincide with each other.

[0056] As described above, the vehicle headlamp 1 of the present embodiment includes the first light sources 31a, 31b, and 31c, the second light source 32, and the projection lens 60. The first light sources 31a, 31b, and 31c emit the first light L1 that forms the low beam light distribution pattern PL. The second light source 32 is disposed to the left of the first light sources 31a, 31b, and 31c, and emits the second light that forms a lateral light distribution pattern PS, at least a part of which is located to the side of the low beam light distribution pattern PL. The projection lens 60 has an entrance surface 62 that is curved convexly toward the rear side in a horizontal cross section and on which the first light L1 and the second light L2 are incident, and an exit surface 63 from which the first light L1 and the second light L2 incident from the entrance surface 62 exit. According to the vehicle headlamp 1 of this embodiment, the first light L1 and the second light L2 are emitted from a single projection lens 60, so that the vehicle headlamp 1 can be prevented from becoming larger in size compared to a case in which a projection lens for emitting the first light L1 and a projection lens for emitting the second light L2 are provided separately.

[0057] In addition, in the vehicle headlamp 1 of this embodiment, when the projection lens is viewed from above, the optical axis LA2 of the second light L2 heading toward the incident surface 62 intersects with a region of the incident surface 62 to the left of the vertex 62t of the incident surface 62. Therefore, in the vehicle headlamp 1 of this embodiment, most of the second light L2 is incident on the region of the incident surface 62 to the left of the vertex 62t of the incident surface 62. In general, when the vertex 62t of the incident surface 62 moves in a direction perpendicular to the first reference surface 64 from a state in which the vertex 62t of the incident surface 62 is located on the first reference surface 64 passing through the center 65c of the line segment 65 connecting the left and right ends 62e of the incident surface 62 and perpendicular to the line segment 65, the width of the region on the first reference surface 64 side from the vertex 62t in the left-right direction becomes longer. Therefore, the average angle between the region of the incident surface 62 and the first reference surface 64 tends to increase and approach 90°. In the vehicle headlamp 1 of this embodiment, the vertex 62t is located to the right of the first reference surface 64. Therefore, according to the vehicle headlamp 1 of the present embodiment, the angle of incidence of the second light L2 on the incident surface 62 is larger than when the vertex 62t is located on the first reference surface 64, and the angle of refraction of the second light L2 on the incident surface 62 is also larger. Therefore, according to the vehicle headlamp 1 of the present embodiment, the propagation direction of the second light L2 from the incident surface 62 toward the exit surface 63 can be made to follow the first reference surface 64, compared to the above case. In general, since the first reference surface 64 extends in the front-rear direction, when the propagation direction of the light toward the exit surface 63 is made to follow the first reference surface 64, the angle of incidence of the light on the exit surface 63 tends to be smaller. Therefore, according to the vehicle headlamp 1 of the present embodiment, the angle of incidence of the second light L2 on the exit surface can be made smaller than when compared to the above case, and the second light L2 is less likely to be totally reflected on the exit surface 63, and energy efficiency can be improved.

[0058] In addition, by reducing the bulge of the incident surface 62 toward the rear side, that is, by moving the position of the apex 62t of the incident surface 62 closer to the exit surface 63, the angle between the incident surface 62 and the first reference surface 64 can be reduced. In this case, however, the focal point on the rear side of the projection lens 60 becomes farther from the projection lens 60, and the distance between the first light sources 31a, 31b, 31c and the second light source 32 and the projection lens 60 may become larger. However, according to the vehicle headlamp 1 of this embodiment, even if the position of the apex 62t is not moved closer to the exit surface 63, it is possible to make it difficult for the second light L2 to be totally reflected by the exit surface 63, and it is possible to suppress an increase in the size of the vehicle headlamp 1.

[0059] In the vehicle headlamp 1 of this embodiment, the exit surface 63 is curved forward in a convex shape in a horizontal cross section. At least a part of the side light distribution pattern PS is located on the right side of the low beam light distribution pattern PL. In addition, when the projection lens 60 is viewed from above, a half line 67 extending from the center 66c of the line segment 66 connecting the left and right ends of the exit surface 63 toward the elbow point EP in the cutoff line CL of the low beam light distribution pattern PL is inclined relative to the second reference plane 68 so as to move away from the second reference plane 68 passing through the center 66c of the line segment 66 and perpendicular to the line segment 66 to the left as it moves forward. In the vehicle headlamp 1 of this embodiment, the direction of the exit surface 63 can be made closer to the direction from the center 66c toward the side light distribution pattern, compared to the case where the half line 67 is located on the second reference plane 68. Therefore, according to the vehicle headlamp 1 of this embodiment, the angle of incidence of the second light L2 on the exit surface 63 can be made smaller than in the above case, making it less likely for the second light L2 to be totally reflected at the exit surface 63, and improving energy efficiency.

[0060] Although the present invention has been described above using the above-mentioned embodiments as examples, the present invention is not limited to these.

[0061] For example, in the above embodiment, the entrance surface 62 is curved convexly toward the rear side in the vertical cross section and the horizontal cross section. However, the entrance surface 62 may be linear in the vertical cross section. Also, in the above embodiment, the exit surface 63 is curved convexly toward the front side in the vertical cross section and the horizontal cross section. However, the exit surface 63 may be linear in the vertical cross section and the horizontal cross section.

[0062] In the above embodiment, the reflector 40, the shade 70, the slope portion 75, and the holder 80 are integrated, and a part of the holder 80 is the second sub-reflector 88. However, these members may be separate, and the holder 80 and the second sub-reflector 88 may be separate, and the vehicle headlamp 1 may not include the slope portion 75.

[0063] In the above embodiment, the second light source 32 is disposed to the left of the first light sources 31a, 31b, and 31c. However, the second light source 32 may be disposed on one side in the left-right direction based on the first light sources 31a, 31b, and 31c. For example, the second light source 32 may be disposed to the right of the first light sources 31a, 31b, and 31c. In this case, the second reflector 40b is disposed to the right of the first light sources 31a, 31b, and 31c, and when the projection lens 60 is viewed from above, the optical axis LA2 of the second light L2 traveling toward the incident surface 62 intersects with an area to the right of the vertex 62t on the incident surface 62, and the vertex 62t of the incident surface 62 is located to the left of the first reference surface 64.

[0064] In the above embodiment, the reflector 40 including the first reflector 40a arranged below the first light sources 31a, 31b, and 31c and the second reflector 40b arranged below the second light source 32 has been described as an example. However, the reflector 40 is not limited as long as the low beam light distribution pattern PL can be formed with the first light L1 and the side light distribution pattern PS can be formed with the second light L2. For example, the first light sources 31a, 31b, and 31c may emit the first light L1 upward, the second light source 32 may emit the second light L2 upward, the first reflector 40a may be arranged above the first light sources 31a, 31b, and 31c, and the second reflector 40b may be arranged above the second light source 32. In addition, the vehicle headlamp 1 may not include the reflector 40 and may not include the shade 70.

[0065] Furthermore, in the above embodiment, an example has been described in which the vehicle headlamp 1 includes the first sub-reflector 90 and the second sub-reflector 88. However, the vehicle headlamp 1 does not necessarily have to include the first sub-reflector 90 and the second sub-reflector 88.

[0066] In the above embodiment, the shade 70 is described as blocking the first light L1 and the second light L2 by reflecting the first light L1 and the second light L2. However, the shade 70 may block the first light L1 and the second light L2 by absorbing the first light L1 and the second light L2. This configuration can prevent the first light L1 and the second light L2 from becoming stray light.

[0067] In the above embodiment, the side light distribution pattern PS is partially located on the right side of the low beam light distribution pattern PL. However, at least a part of the side light distribution pattern PS may be located on the side of the low beam light distribution pattern PL. For example, a part of the side light distribution pattern PS may be located on the left side of the low beam light distribution pattern PL. In this case, for example, the second light source 32 is disposed on the right side of the first light sources 31a, 31b, and 31c. That is, the second light source 32 is located on the opposite side to the side on which the side light distribution pattern PS is located with respect to the first light sources 31a, 31b, and 31c. Also, the entire side light distribution pattern PS may be located on the right or left side of the low beam light distribution pattern PL. [Industrial Applicability]

[0068] According to the present invention, a vehicle headlamp that can improve energy efficiency while suppressing an increase in size is provided, and can be used in fields such as vehicle headlamps for automobiles and the like. [Explanation of symbols]

[0069] 1. Vehicle headlamp 20. Heat sink 31a, 31b, 31c...1st light source 32...Second light source 40...Reflector 60...Projection lens 62...Incidence plane 62t...vertex 63....Exit surface 64...1st reference plane 65,66... ​​line segment 65c,66c...center 67...half line 68...Second reference plane 70···Shades

Claims

1. A first light source that emits a first light that forms a low beam light distribution pattern; a second light source that is disposed on one side in a left-right direction based on the first light source and emits a second light that forms a side light distribution pattern, at least a portion of which is located to the side of the low beam light distribution pattern; a projection lens disposed forward of the first light source and the second light source, the projection lens having an incident surface curved convexly toward the rear side in a horizontal cross section, into which the first light and the second light are incident, and an exit surface from which the first light and the second light incident from the incident surface exit; Equipped with When the projection lens is viewed from above, an optical axis of the second light traveling toward the incident surface intersects with a region of the incident surface that is closer to the second light source than a vertex of the incident surface, The vertex is located on the side opposite to the second light source side with respect to a first reference plane that passes through the center of a line segment connecting both the left and right ends of the incident surface and is perpendicular to the line segment. A vehicle headlamp characterized by:

2. The exit surface is curved convexly forward in a horizontal cross section, At least a part of the side light distribution pattern is located on an opposite side to the one side in the low beam light distribution pattern, When the projection lens is viewed from above, a half line extending from the center of a line segment connecting both the left and right ends of the exit surface toward an elbow point in the cutoff line of the low beam light distribution pattern is inclined with respect to the second reference plane so as to move away from the second reference plane that passes through the center of the line segment connecting the left and right ends of the exit surface and is perpendicular to the line segment toward the one side as it moves forward.

2. The vehicle headlamp according to claim 1.

3. The exit surface is curved convexly forward in a horizontal cross section, In the left-right direction, the curvature of the light exit surface decreases toward the outer edge of the light exit surface.

2. The vehicle headlamp according to claim 1.

4. The vertex of the entrance surface is located on the optical axis of the projection lens.

4. The vehicle headlamp according to claim 1, wherein the first and second electrodes are arranged in a first direction.

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