Vehicle lighting

Abstract

The present invention provides a vehicle lighting device that can form a driving light distribution pattern with a desired light distribution by emitting a portion of the light from the high beam unit through the emission surface of the lens member of the low beam unit. [Solution] The vehicle light fixture 10 includes a low beam unit 18 that forms a passing light distribution pattern LP with light from the upper emission surface 25 of the upper lens member 15, a high beam unit 19 that forms a driving light distribution pattern HP with light from the lower emission surface 33 of the lower light source unit (12, 16), and a projection lens 17 that projects light from both units (18, 19). The upper lens member 15 has a lower light incidence surface 28 that faces the upper emission surface 25 and allows a portion of the light from the lower emission surface 33 to enter, and the lower light source unit has an emission light axis Ao tilted with respect to the projection light axis Ap so that the lower emission surface 33 is directed toward the lower light incidence surface 28.

Description

Technical Field

[0001] The present disclosure relates to vehicle lamps.

Background Art

[0002] It has been considered that a vehicle lamp is provided with a low beam unit that forms a passing light distribution pattern on the upper side and a high beam unit that forms a driving light distribution pattern on the lower side (see, for example, Patent Document 1). In this vehicle lamp, a part of the light of the high beam unit is made to enter the lens member of the low beam unit and is emitted from the emission surface of the lens member, so that a driving light distribution pattern can be formed so as to eliminate a dark portion between the patterns for passing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above vehicle lamp, a part of the light of the high beam unit is made to enter from the reflecting surface in the lens member of the low beam unit. Since the reflecting surface is provided to reflect the light for forming the passing light distribution pattern guided into the lens member toward the emission surface, it is inclined with respect to the emission surface. For this reason, in the above vehicle lamp, it is not easy to make a part of the light of the high beam unit incident from the reflecting surface travel near the cut-off edge portion on the emission surface of the lens member, and it becomes difficult to obtain a light distribution suitable for the driving light distribution pattern.

[0005] This disclosure has been made in view of the above circumstances, and aims to provide a vehicle lighting device that can form a driving light distribution pattern with a desired light distribution distribution by having a portion of the light from the high beam unit exit from the exit surface of the lens member of the low beam unit. [Means for solving the problem]

[0006] The vehicle light fixture of the present disclosure comprises a low-beam unit that emits light from the upper emission surface of an upper lens member to form a passing light distribution pattern, a high-beam unit that emits light from the lower emission surface of a lower light source to form a driving light distribution pattern, and a projection lens that projects light from the low-beam unit and light from the high-beam unit, wherein the upper lens member has a lower light incidence surface that faces the upper emission surface and allows a portion of the light emitted from the lower emission surface to be incident, and the lower light source is characterized in that its own emission light axis is tilted with respect to the projection light axis of the projection lens and the lower emission surface is directed toward the lower light incidence surface. [Effects of the Invention]

[0007] According to the vehicle lighting device of this disclosure, a portion of the light from the high beam unit is emitted from the emission surface of the lens member of the low beam unit, thereby forming a driving light distribution pattern with a desired light distribution. [Brief explanation of the drawing]

[0008] [Figure 1] This is an explanatory diagram showing the vehicle lighting device of Embodiment 1 according to this disclosure, viewed from the front in the front-rear direction. [Figure 2] This is an explanatory diagram showing a vehicle light fixture from the rear in the front-to-back direction. [Figure 3] This is an explanatory diagram showing the upper and lower substrates together in a cross-section obtained along line II shown in Figure 2. [Figure 4] This is an explanatory diagram showing the upper lens component as viewed from the rear in the front-to-back direction. [Figure 5] This is an explanatory diagram showing the upper lens component as viewed from the front in the front-to-back direction. [Figure 6] Figure 4 is an explanatory diagram showing a cross-section obtained along the line II-II. [Figure 7] This is an explanatory diagram showing the upper lens component viewed from the rear in the front-to-back direction. [Figure 8] This is an explanatory diagram showing the lower lens component as viewed from the rear in the front-to-back direction. [Figure 9] This is an explanatory diagram showing the lower lens component as viewed from the front in the front-to-back direction. [Figure 10] Figure 8 is an explanatory diagram showing a cross-section obtained along the line III-III. [Figure 11] This is an explanatory diagram showing how light emitted from each light source in a vehicle's lighting system travels. [Figure 12] This is an explanatory diagram showing how a passing light distribution pattern is formed on a screen where a horizontal line and a vertical line intersect at the center of the projection optical axis. [Figure 13] The above diagram illustrates how the light distribution pattern for driving is formed on the screen. [Figure 14] The above diagram illustrates how the light distribution patterns for passing vehicles and for driving vehicles are formed on the screen shown. [Modes for carrying out the invention]

[0009] Embodiment 1 of the vehicle lighting device according to this disclosure will be described below with reference to the drawings. In Figures 1 and 2, the upper substrate 13 and lower substrate 14 are omitted in order to facilitate understanding of the positional relationship and configuration of the upper light source 11, the lower light source 12, the upper lens member 15, the lower lens member 16, and the projection lens 17. Also, in Figure 11, the cross-sectional lines of each component are omitted in order to facilitate understanding of how light propagates. [Embodiment 1]

[0010] A vehicle lamp 10 of Embodiment 1, an embodiment of the vehicle lamp according to this disclosure, will be described with reference to Figures 1 to 14. The vehicle lamp 10 of Embodiment 1 is used as a headlight device for a vehicle such as an automobile. This vehicle lamp 10 is installed in lamp chambers formed by lamp housings, the open front ends of which are covered by outer lenses, on both the left and right sides of the front of the vehicle. The vehicle lamp 10 is installed in the lamp chambers via an optical axis adjustment mechanism for the vertical direction and an optical axis adjustment mechanism for the horizontal direction, and illuminates the front of the vehicle as appropriate. In the following description, in the vehicle lamp 10, the direction in which the vehicle moves is defined as the front-rear direction (Z in the drawings), the vertical direction when the front-rear direction is aligned with the horizontal plane is defined as the up-down direction (Y in the drawings), and the direction perpendicular to the front-rear direction and the up-down direction (horizontal direction) is defined as the width direction (X in the drawings). Here, the vehicle lighting fixture 10, while having essentially the same configuration for those installed on the left side of the vehicle and those installed on the right side, is reversed or translated in the width direction (left and right). Therefore, the following explanation will use the vehicle lighting fixture 10 installed on the right side.

[0011] As shown in Figures 1 to 3, the vehicle light fixture 10 of Embodiment 1 comprises an upper light source 11, a lower light source 12, an upper substrate 13, a lower substrate 14, an upper lens member 15, a lower lens member 16, and a projection lens 17, forming a projector-type light fixture unit with the front-to-back direction as the optical axis. The upper light source 11 is mounted on the upper substrate 13 and is arranged in a row of five at approximately equal intervals in the width direction. The lower light source 12 is mounted on the lower substrate 14 and is arranged in a row of four at approximately equal intervals in the width direction. Each of these light sources (11, 12) is composed of a light-emitting element such as an LED (Light Emitting Diode).

[0012] Each substrate (13, 14) is in a plate shape formed of an aluminum substrate. Note that each substrate (13, 14) may be formed of a resin material such as a glass epoxy substrate or may be formed of other materials. Also, each substrate (13, 14) may be a heat sink formed of aluminum or the like and having excellent heat dissipation properties. In this case, each light source can be mounted on one surface of the heat sink and then connected to a circuit board provided on the heat sink by wire bonding. Wiring patterns and connector terminals for electrically connecting the corresponding light sources (11, 12) are provided on each of these substrates (13, 14). Each substrate (13, 14) appropriately supplies power from a lighting control circuit via the connector terminals to appropriately light the corresponding light sources (11, 12). Each of these substrates (13, 14) is attached to, for example, a heat sink formed of an aluminum plate, an aluminum die-cast, or a resin having heat conductivity. The heat sink can be configured to mainly release the heat generated by each light source (11, 12) to the outside from each heat radiation fin, for example, by providing a plurality of heat radiation fins. Also, the heat sink may be configured as a mounting member to which the upper lens member 15, the lower lens member 16, and the projection lens 17 are attached via a support member or the like.

[0013] The upper lens member 15 is provided corresponding to the five upper light sources 11 and is formed of a transparent resin. This upper lens member 15 guides the light emitted from each upper light source 11 inward and is an optical lens that forms an intersection light distribution pattern LP (see FIG. 12) in cooperation with the projection lens 17. As shown in FIGS. 4 to 7, the upper lens member 15 is provided with five upper incident portions 21 on the upper side in the vertical direction at the rear side in the front-rear direction. Each upper incident portion 21 corresponds individually to each upper light source 11 and has optical characteristics (such as the shape of the surface) according to the required light distribution image for each while having basically the same configuration as each other.

[0014] As shown in FIGS. 4, 6, and 7, each upper incident portion 21 has a portion facing the corresponding upper light source 11 protruding toward the upper light source 11 side, and its center is recessed on the side opposite to the upper light source 11, and has an upper opposed incident surface 21a, an upper inclined incident surface 21b, and an upper annular reflection surface 21c. The upper opposed incident surface 21a is convexly curved toward the upper light source 11 side, and the upper light source 11 is positioned near the focus on the rear side (the upper light source 11 side) (the rear focus). The upper opposed incident surface 21a makes the light emitted from the upper light source 11 enter the upper lens member 15 as parallel light traveling substantially parallel to the axis of the upper incident portion 21, and makes it travel toward the upper first reflection surface 22 of the upper lens member 15. Note that this parallel light (parallel light) refers to light in a collimated state after passing through the upper opposed incident surface 21a. The parallel light in each upper incident portion 21 does not necessarily have to be completely parallel, and may include substantially parallel light.

[0015] The upper inclined incident surface 21b is provided so as to surround the upper opposed incident surface 21a in a frustum shape while protruding from the upper opposed incident surface 21a toward the upper light source 11 side. The upper inclined incident surface 21b makes the light from the upper light source 11 that does not travel toward the upper opposed incident surface 21a enter the upper lens member 15. The upper annular reflection surface 21c is provided so as to surround the upper inclined incident surface 21b in a frustum shape, and is positioned where the light incident from the upper inclined incident surface 21b into the upper lens member 15 travels. The upper annular reflection surface 21c reflects the light incident from the upper inclined incident surface 21b, and makes it travel toward the upper first reflection surface 22 of the upper lens member 15 as parallel light traveling substantially parallel to the axis of the upper incident portion 21. Note that the upper annular reflection surface 21c may reflect light using total reflection, or may reflect light by attaching aluminum, silver, etc. by vapor deposition, painting, or the like.

[0016] The upper first reflective surface 22 is provided on the front side in the front-to-back direction of each upper incident portion 21. This upper first reflective surface 22 reflects the light incident from each upper incident portion 21 toward the upper second reflective surface 23 of the upper lens member 15. In Embodiment 1, the upper first reflective surface 22 is composed of four free-form surfaces arranged in the width direction (see Figure 5). Each of these free-form surfaces is based on a parabolic surface with a focus near the cutoff edge 26 of the upper exit portion 24 of the upper lens member 15, while considering reflection at the upper second reflective surface 23. Therefore, the upper first reflective surface 22 reflects the light incident from the upper incident portion 21, causing that light to propagate toward the cutoff edge 26. Note that the upper first reflective surface 22 may utilize total internal reflection, undergo reflection processing, or have other configurations, as long as it reflects as described above. Furthermore, the upper first reflective surface 22 may be a single surface, and is not limited to the configuration of Embodiment 1.

[0017] The upper second reflective surface 23 is located below the upper first reflective surface 22 in the vertical direction. This upper second reflective surface 23 reflects the light reflected by the upper first reflective surface 22 toward the upper emission portion 24 of the upper lens member 15. Here, since the upper first reflective surface 22 is set as described above, the upper second reflective surface 23 concentrates the reflected light near the cutoff edge 26 and propagates it toward the upper emission portion 24.

[0018] The upper emission portion 24 is located on the front side in the front-to-back direction of the upper second reflective surface 23. The front surface of this upper emission portion 24 in the front-to-back direction is the upper emission surface 25, and the lower edge in the vertical direction of the upper emission surface 25 is the cutoff edge portion 26. The upper emission surface 25 is positioned opposite the upper second reflective surface 23 in the front-to-back direction and is a plane or free-form surface that emits light from at least the upper second reflective surface 23. The cutoff edge portion 26 forms a cutoff line CL (see Figure 12) and has a shape in which multiple horizontal edges (corresponding to the horizontal parts of the cutoff line CL) and multiple inclined edges (corresponding to the inclined parts of the cutoff line CL) are joined together. This cutoff edge portion 26 is located near the focal point (rear focal point) of the projection lens 17.

[0019] In the upper lens member 15, an upper bottom reflective surface 27 is provided at the lower end in the vertical direction, between the upper second reflective surface 23 and the upper emission section 24. This upper bottom reflective surface 27 extends from the cutoff edge 26 at the lower end of the upper emission surface 25 toward the rear in the front-rear direction. The upper bottom reflective surface 27 reflects the light that has been reflected by the upper second reflective surface 23 and is traveling below the upper emission surface 25 of the upper emission section 24, and directs it toward the upper emission surface 25.

[0020] Therefore, the upper emission section 24 emits light from the upper emission surface 25 and does not emit light that has traveled below the cutoff edge 26, so that the shape of the cutoff edge 26 can be reflected in the emitted light. Furthermore, even when the vehicle light fixture 10 is installed on the left side of the vehicle, the relationship between the direction of inclination and height of the cutoff edge 26 is not reversed in the width direction. That is, the vehicle light fixture 10 is reversed in the width direction on the right and left sides of the vehicle, but the inclination of the cutoff edge 26 of the upper emission section 24 is the same direction for both sides.

[0021] In Embodiment 1, the upper bottom reflective surface 27 extends to the rear in the front-to-back direction while maintaining the shape of the cutoff edge 26. Therefore, the upper bottom reflective surface 27 is constructed by joining together multiple planes that extend to the rear in the front-to-back direction along each horizontal edge and each inclined edge of the cutoff edge 26. In Embodiment 1, the step portion 26a located approximately in the center in the width direction is at the lowest point in the vertical direction, and the cutoff edge 26 is inclined so as it moves toward each outer edge portion 26b located on both sides in the width direction, displacing upward. Therefore, even at the locations of each horizontal edge, the cutoff edge 26 is inclined with respect to a plane perpendicular to the vertical direction. Here, since the cutoff edge 26 is a combination of each horizontal edge and each inclined edge, there are places where the direction of inclination is reversed in some parts, but overall it is inclined so as it moves toward each outer edge portion 26b, displacing upward. Accordingly, the upper bottom reflective surface 27 has a stepped portion 27a that is continuous with the stepped portion 26a of the cutoff edge 26 located at the lowest point in the vertical direction, and is inclined to be displaced upward as it moves towards the outer edge portions 27b located on both sides in the width direction.

[0022] In the upper lens member 15, a lower light incident surface 28 is provided between the upper second reflective surface 23 and the upper bottom reflective surface 27. This lower light incident surface 28 spans the lower end in the vertical direction of the upper second reflective surface 23 and the rear end in the front-to-back direction of the upper bottom reflective surface 27. The lower light incident surface 28 is positioned directly opposite the upper output surface 25, that is, facing it in the front-to-back direction. This lower light incident surface 28 rises vertically from the rear end of the upper bottom reflective surface 27, and in Embodiment 1, it is inclined to shift slightly forward in the front-to-back direction as it moves upward from the rear end of the upper bottom reflective surface 27. Therefore, the lower light incident surface 28 is located at the lower end in the vertical direction of the upper lens member 15 and at the rear end in the front-to-back direction of the lower part of the upper lens member 15. In this embodiment, the lower light incident surface 28 of the embodiment 1 has its lower edge defined by the upper bottom reflective surface 27. Therefore, its dimensions in the vertical direction are largest at the midpoint in the width direction and gradually decrease as it moves outward on both sides in the width direction.

[0023] As shown in Figures 8 to 10, the lower lens member 16 is provided corresponding to the four lower light sources 12 and is made of transparent resin. This lower lens member 16 is an optical lens that guides the light emitted from each lower light source 12 inward and works in cooperation with the projection lens 17 to form the light distribution pattern HP for driving (see Figure 13). The lower lens member 16 has four lower incident portions 31 on the rear side in the front-rear direction and on the lower side in the vertical direction. Each lower incident portion 31 corresponds individually to each lower light source 12 and has basically the same configuration as the others, but has optical characteristics (surface shape, etc.) according to the light distribution image required for each.

[0024] As shown in Figures 8 and 10, each lower incident portion 31 is formed with a portion facing the corresponding lower light source 12 protruding towards the lower light source 12, and its center recessed on the opposite side from the lower light source 12, and has a lower opposing incident surface 31a, a lower inclined incident surface 31b, and a lower annular reflective surface 31c. The lower opposing incident surface 31a is curved convexly toward the lower light source 12, and the lower light source 12 is positioned near the rear (lower light source 12 side) focal point (rear focal point). The lower opposing incident surface 31a causes the light emitted from the lower light source 12 to enter the lower lens member 16 as parallel light traveling approximately parallel to the axis of the lower incident portion 31, and directs it toward the lower exit portion 32 of the lower lens member 16.

[0025] The lower inclined incident surface 31b is provided in a frustoconical shape, protruding from the lower opposing incident surface 31a toward the lower light source 12. This lower inclined incident surface 31b causes light from the lower light source 12 that does not travel toward the lower opposing incident surface 31a to enter the lower lens member 16. The lower annular reflective surface 31c is provided in a frustoconical shape, surrounding the lower inclined incident surface 31b, and is positioned where light incident from the lower inclined incident surface 31b into the lower lens member 16 travels. The lower annular reflective surface 31c reflects the light incident from the lower inclined incident surface 31b and causes it to travel toward the lower exit portion 32 of the lower lens member 16 as parallel light traveling approximately parallel to the axis of the lower incident portion 31. The lower annular reflective surface 31c may reflect light using total internal reflection, or it may reflect light by bonding aluminum, silver, or the like through vapor deposition or painting. The parallel light at each of these lower incident portions 31 is not necessarily limited to perfectly parallel light, but may include approximately parallel light.

[0026] The lower emission section 32 is located on the front side of the lower incidence section 31 in the front-rear direction. This lower emission section 32 partially protrudes forward from the lower lens member 16, and its protruding end is the lower emission surface 33. The lower emission surface 33 emits light incident from each lower incidence section 31 toward the projection lens 17. In Embodiment 1, the lower emission surface 33 is composed of five free-form surfaces arranged in the width direction (see Figure 10). Each of these free-form surfaces is a free-form surface based on a convex sphere with a focal point near the cutoff edge 26 of the upper emission section 24 of the upper lens member 15. Therefore, the lower emission surface 33 causes light incident from each lower incidence section 31 to travel toward the cutoff edge 26. Furthermore, the lower exit surface 33 is not limited to the configuration of Embodiment 1; as long as it allows light incident from the lower ingress section 31 to propagate towards the vicinity of the cutoff edge 26, the shape and number of surfaces can be set as appropriate.

[0027] Therefore, in Embodiment 1, each lower light source 12 mounted on the lower substrate 14 and the lower lens member 16 function as a lower light source unit that emits light from the lower emission surface 33 to form the light distribution pattern HP for driving in the high beam unit 19. The lower light source unit is not limited to the configuration of Embodiment 1, as long as it emits light from the lower emission surface 33 to form the light distribution pattern HP for driving in the high beam unit. The shape and configuration of the lower lens member 16 may differ (for example, the same structure as the upper lens member 15 but inverted vertically), and it may consist only of one or more lower light sources 12, or it may consist of a light source and a reflector. Here, the lower emission surface is the light-emitting surface of the lower light source 12 when it consists only of the lower light source 12, and the reflective surface of the reflector when it consists of a light source and a reflector. When the reflective surface of the reflector is the lower emission surface, the axis of the reflector corresponds to the emission light axis Ao described later.

[0028] As shown in Figures 1 to 3, the lower lens member 16 is positioned below the projection optical axis Ap of the projection lens 17. Furthermore, the lower lens member 16 is tilted so that its own emission optical axis Ao approaches the projection optical axis Ap as it moves forward in the front-to-back direction, and its lower emission surface 33 is directed toward the lower light incidence surface 28 of the upper lens member 15. As a result, in the direction in which the emission optical axis Ao extends, a portion of the upper part of the lower emission surface 33 of the lower lens member 16 faces the lower light incidence surface 28 of the upper lens member 15.

[0029] The projection lens 17 is provided on the front side in the front-rear direction of the upper emission surface 25 (upper emission portion 24) of the upper lens member 15 and the lower emission surface 33 (lower emission portion 32) of the lower lens member 16. This projection lens 17 is a convex lens molded from a resin material and is a free-form surface based on a sphere with its focal point (rear focal point) located near the cutoff edge 26 of the upper emission portion 24 of the upper lens member 15. The optical axis of this projection lens 17 becomes the projection optical axis Ap of the vehicle light fixture 10, and in Embodiment 1, it coincides with the front-rear direction.

[0030] The projection lens 17 projects the shape of the upper emission surface 25, including the cutoff edge 26, onto a screen where a horizontal line and a vertical line intersect, with the projection optical axis Ap as the origin, by irradiating it with light from the upper emission surface 24. As a result, the projection lens 17 forms a passing light distribution pattern LP (see Figure 12) on the screen, which has a cutoff line CL on the projection optical axis Ap, making the area near the projection optical axis Ap the brightest while illuminating a large area in the width direction below the cutoff line CL. Furthermore, the projection lens 17 forms a driving light distribution pattern HP (see Figure 13) on the screen, which irradiates the upper part of the passing light distribution pattern LP by irradiating it with light from the lower emission surface 33.

[0031] Therefore, in the vehicle light fixture 10, the five upper light sources 11, the upper lens member 15, and the projection lens 17 function as a low beam unit 18 that forms a passing light distribution pattern LP. In addition, in the vehicle light fixture 10, the four lower light sources 12, the lower lens member 16, and the projection lens 17 function as a high beam unit 19 that forms a driving light distribution pattern HP. Furthermore, in the vehicle light fixture 10, as will be described later, a portion of the light emitted from the lower lens member 16 is incident on the upper lens member 15 from the lower light incident surface 28 and emitted from its upper exit surface 25 to form an additional range HPa of the driving light distribution pattern HP. Strictly speaking, the upper lens member 15 also functions as a high beam unit 19.

[0032] This vehicle lighting fixture 10 is constructed as a single unit with the upper light source 11, lower light source 12, upper substrate 13, lower substrate 14, upper lens member 15, lower lens member 16, and projection lens 17 supported by support members (not shown), in the positional relationship shown in Figures 1 to 3.

[0033] In this vehicle light fixture 10, when the five upper light sources 11 in the low beam unit 18 are lit, the light is directed into the upper lens member 15 from the corresponding upper incident section 21. The upper lens member 15 focuses and reflects the incident light at the upper first reflective surface 22, then reflects it at the upper second reflective surface 23, and emits it from the upper emission surface 25 of the upper emission section 24. The vehicle light fixture 10 then projects the light emitted from the upper emission surface 25 with the projection lens 17 to form a passing light distribution pattern LP (see Figure 12). Therefore, by liting each upper light source 11 and forming the passing light distribution pattern LP, the vehicle light fixture 10 can achieve the passing light distribution (so-called low beam).

[0034] Furthermore, in the vehicle lighting unit 10, when the four lower light sources 12 are lit in the high beam unit 19, the light is directed into the lower lens member 16 from the corresponding lower incident portions 31. The lower lens member 16 then emits the incident light from the lower exit surface 33 of the lower exit portion 32. The vehicle lighting unit 10 then projects the light emitted from the lower lens member 16 with the projection lens 17 to form a driving light distribution pattern HP (see Figure 13) that partially overlaps with the upper end of the passing light distribution pattern LP and illuminates the upper part of the passing light distribution pattern LP. Therefore, by liting each of the lower light sources 12 in addition to each of the upper light sources 11 to form the driving light distribution pattern HP, the vehicle lighting unit 10 can achieve the driving light distribution (so-called high beam (see Figure 14)).

[0035] Here, the vehicle light fixture 10 aligns a portion of the upper side of the lower emission surface 33 of the lower lens member 16 with the lower light incidence surface 28 of the upper lens member 15. As a result, as shown in Figure 11, the vehicle light fixture 10 can cause light emitted from the upper side of the lower emission surface 33 to be incident on the upper lens member 15 from the lower light incidence surface 28. The vehicle light fixture 10 directs the light incident from the lower light incidence surface 28 toward the vicinity of the cutoff edge 26 on the upper emission surface 25 and emits it from the upper emission surface 25. Since this light is emitted from each lower light source 12 and also from the vicinity of the cutoff edge 26 of the upper emission surface 25, as shown in Figure 13, it forms an additional range HPa in the driving light distribution pattern HP that extends downward from the cutoff line CL of the passing light distribution pattern LP.

[0036] This additional range HPa is designed to be brightest at the position of the projected optical axis Ap along the horizontal line, becoming dimmer as it moves away from the axis, and brightest at the position of the projected optical axis Ap along the vertical line, becoming dimmer as it moves downwards. In other words, the additional range HPa illuminates the area below the cutoff line CL centered on the projected optical axis Ap, thereby illuminating the driving light distribution pattern HP up to the area below the projected optical axis Ap. As a result, the vehicle lamp 10 not only illuminates the upper part of the passing light distribution pattern LP with the driving light distribution pattern HP, but also illuminates the additional range HPa superimposed on the passing light distribution pattern LP (see Figure 14). Therefore, when the vehicle lamp 10 switches from the passing light distribution to the driving light distribution, not only does the area above the cutoff line CL of the passing light distribution pattern LP become brighter, but the area around the projected optical axis Ap in the passing light distribution pattern LP can also be made even brighter. Therefore, the vehicle light fixture 10 brightens the area around the projection light axis Ap that the occupants of the vehicle it is installed on, especially the driver, are paying attention to, making it easy for them to see that the light distribution has been switched, and improving visibility at a distance. In addition, the vehicle light fixture 10 superimposes an additional range HPa on the passing light distribution pattern LP that forms a gradient where the area around the projection light axis Ap is the brightest and gradually gets darker as you move away from it, thereby improving the appearance of the passing light distribution pattern LP and making it appear brighter.

[0037] Furthermore, in the vehicle lighting unit 10, the low beam unit 18 allows light from each upper light source 11 to be incident from each upper incident part 21, so that the light from each upper light source 11, which has a wide spread, can be efficiently incident onto the upper lens member 15. Then, in the vehicle lighting unit 10, the upper lens member 15 totally reflects the incident light between the upper first reflective surface 22 and the upper second reflective surface 23, forming a cutoff line CL, so that the passing light distribution pattern LP can be formed while efficiently utilizing that light. In addition, in the vehicle lighting unit 10, the high beam unit 19 allows light from each lower light source 12 to be incident from each lower incident part 31, so that the light from each lower light source 12, which has a wide spread, can be efficiently incident onto the lower lens member 16.

[0038] In addition, in the vehicle light fixture 10, at least a portion of the upper second reflective surface 23 and the upper bottom reflective surface 27 of the upper lens member 15 are positioned so as to overlap with the upper first reflective surface 22 in the optical axis direction along the projected optical axis Ap. That is, when viewed in the vertical direction, the upper second reflective surface 23 and the upper bottom reflective surface 27 of the upper lens member 15 are positioned so as to overlap with at least a portion of the upper first reflective surface 22. As a result, the vehicle light fixture 10 can be miniaturized while still achieving the optical functions and effects described above.

[0039] The vehicle light fixture 10 has an upper lens member 15 that receives light from each upper light source 11 as parallel light at each upper incident section 21, and then reflects it at the upper first reflective surface 22 so as to concentrate it near the cutoff edge 26. As a result, the vehicle light fixture 10 can concentrate the light to a smaller area with a simpler configuration using the upper lens member 15, and the brightness distribution in the formed light distribution pattern can be more precisely targeted. This is due to the following: First, the spread at the point of focus is due to the fact that the light-emitting area of ​​each upper light source 11 is not a point but has a predetermined area. And, in conventional lens member configurations, it is conceivable to concentrate the light near the cutoff edge by adjusting the lens surface of the incident section. However, with such a configuration, the spread light from the corresponding light source is concentrated only at the incident section, and the shape of the lens surface of the incident section becomes complex. Furthermore, in such a configuration, since the light is focused on a single surface, it becomes difficult to direct light from areas far from the light-emitting point (which is the result of the optical design) to the set focusing position, due to the light-emitting area of ​​the light source having a predetermined area. For these reasons, such a configuration leads to complexity, makes it difficult to focus light into a small area like the vehicle lighting device 10 of this disclosure, and makes it difficult to achieve the desired brightness distribution in the resulting light distribution pattern.

[0040] Here, we will explain the challenges of conventional vehicle lighting technology. Conventional vehicle lighting devices direct a portion of the light from a high-beam unit, located below the low-beam unit, into the lens element of the low-beam unit from its reflective surface, and then emit it from its emission surface in the direction of the projected optical axis. Thus, conventional vehicle lighting devices use the reflective surface of the lens element of the low-beam unit as the point of incidence for a portion of the light from the high-beam unit. This reflective surface is inclined with respect to the emission surface and the projected optical axis because it is provided to reflect the light intended for forming the passing light distribution pattern guided into the lens element toward the emission surface. In other words, this reflective surface is directed upward to reflect light traveling from above toward the emission surface, so it refracts light incident from the outside further upward, making it difficult to direct it along the projected optical axis. Here, a cutoff edge is provided at the lower end of the emission surface. Therefore, with conventional vehicle lighting fixtures, it is not easy to direct a portion of the light from the high-beam unit, which is incident from the reflective surface, towards the vicinity of the cutoff edge on the emission surface, making it difficult to achieve a light distribution pattern that is intended for driving.

[0041] In contrast, the vehicle light fixture 10 of this disclosure has a lower light incident surface 28 in the upper lens member 15, positioned between the upper second reflective surface 23 and the upper bottom reflective surface 27, so as to be directly opposite the upper emission surface 25. That is, the lower light incident surface 28 does not reflect the light guided into the upper lens member 15 toward the upper emission surface 25, and therefore can be positioned directly opposite the upper emission surface 25. As a result, the vehicle light fixture 10 can direct the light from the lower emission surface 33 of the lower lens member 16, which is incident from the lower light incident surface 28, toward the vicinity of the cutoff edge 26. This allows the vehicle light fixture 10 to extend the driving light distribution pattern HP to below the cutoff line CL in the passing light distribution pattern LP, not only filling the dark area in between, but also illuminating below the cutoff line CL. Therefore, the vehicle lighting device 10 can form a driving light distribution pattern HP with a desired light distribution distribution by having a portion of the light from the high beam unit 19 be emitted from the upper emission surface 25 of the upper lens member 15 of the low beam unit 18.

[0042] In particular, the vehicle lamp 10 of Embodiment 1 is tilted such that the lower light incident surface 28 is slightly displaced forward in the front-rear direction as it moves upward from the rear end of the upper bottom reflective surface 27. As a result, the vehicle lamp 10 can more easily direct the light from the lower emission surface 33 of the lower lens member 16, which is positioned below the upper lens member 15, toward the vicinity of the cutoff edge 26. This allows the vehicle lamp 10 to actively brighten the area around the easily noticeable projection light axis Ap, making it easy to see that the light distribution has been switched, and improving visibility at a distance.

[0043] Furthermore, in the vehicle lamp 10 disclosed herein, the lower lens member 16 is positioned below the projection optical axis Ap of the projection lens 17, and the upper lens member 15 is positioned diagonally above the front side of the lower lens member 16 in the front-rear direction. In addition, the vehicle lamp 10 is provided with the lower lens member 16 tilted so that the emitted optical axis Ao approaches the projection optical axis Ap as it moves forward in the front-rear direction, and its lower emitted surface 33 is directed toward the lower light incident surface 28 of the upper lens member 15. Furthermore, in the vehicle lamp 10, in the direction in which the emitted optical axis Ao extends, a portion of the upper part of the lower emitted surface 33 of the lower lens member 16 faces the lower light incident surface 28 of the upper lens member 15. As a result, the vehicle lamp 10 can more appropriately direct a portion of the light emitted from the lower emitted surface 33 into the lower light incident surface 28. Furthermore, even if the vehicle light fixture 10 has a portion of the upper side of the lower emission surface 33 facing the lower light incident surface 28, it is still possible to ensure that an area of ​​the lower emission surface 33 is exposed when viewed from the projection lens 17 side in the direction along the projection optical axis Ap. This is because if the lower lens member 16 is not tilted and a portion of the upper side of the lower emission surface 33 faces the lower light incident surface 28, the area of ​​the lower emission surface 33 that is exposed when viewed from the projection lens 17 side decreases. As a result, the vehicle light fixture 10 can easily ensure that the amount of light traveling directly from the lower lens member 16 to the projection lens 17, and the light distribution pattern HP for driving can be formed more appropriately.

[0044] Furthermore, in the vehicle lamp 10 of this disclosure, the upper bottom reflective surface 27 between the lower light incident surface 28 and the upper light exit surface 25 of the upper lens member 15 is inclined such that the stepped portion 27a is positioned at the lowest point, and the surface is displaced upward towards each outer edge portion 27b. Therefore, when the upper bottom reflective surface 27 reflects light that has traveled back to itself from the light incident surface 28 towards the upper light exit surface 25, it tilts the direction of that light's propagation toward the projection optical axis Ap. As a result, the vehicle lamp 10 can reflect light incident from the lower light incident surface 28 toward the upper light exit surface 25 so that it approaches the projection optical axis Ap. Therefore, the vehicle light fixture 10 can more appropriately form the additional range HPa of the passing light distribution pattern LP near the projection optical axis Ap while making it brightest near the projection optical axis Ap. In addition, the lower light incident surface 28 of Embodiment 1 has its dimensions in the vertical direction largest at the midpoint in the width direction and gradually decreases towards both outer sides in the width direction, which helps to form the additional range HPa with the brightness distribution described above.

[0045] As an example of a vehicle lighting device related to this disclosure, vehicle lighting device 10 can achieve the following effects.

[0046] The vehicle light fixture 10 includes a low-beam unit 18 that emits light from the upper emission surface 25 of the upper lens member 15 to form a passing light distribution pattern LP, a high-beam unit 19 that emits light from the lower emission surface 33 of the lower lens member 16, which serves as a lower light source, to form a driving light distribution pattern HP, and a projection lens 17 that projects light from both units (18, 19). The upper lens member 15 has a lower light incidence surface 28 that faces the upper emission surface 25 and receives a portion of the light emitted from the lower emission surface 33. The lower lens member 16 has its own emission optical axis Ao tilted with respect to the projection optical axis Ap of the projection lens 17 so that its lower emission surface 33 is directed toward the lower light incidence surface 28. Therefore, the vehicle lamp 10 allows the light from the lower exit surface 33 of the lower lens member 16, which is incident from the lower light incident surface 28, to proceed to the vicinity of the cutoff edge 26, and ensures that an area of ​​the lower exit surface 33 is exposed when viewed from the projection lens 17 side in the direction along the projection optical axis Ap. Thus, the vehicle lamp 10 can form a driving light distribution pattern HP that extends to below the cutoff line CL in the passing light distribution pattern LP, and it becomes easy to ensure the amount of light that proceeds directly from the lower lens member 16 to the projection lens 17, thereby appropriately forming the driving light distribution pattern HP. In addition, the vehicle lamp 10 positions the lower lens member 16 below the projection optical axis Ap of the projection lens 17. Therefore, the vehicle lamp 10 can more appropriately ensure an area of ​​the lower exit surface 33 that is exposed when viewed from the projection lens 17 side in the direction along the projection optical axis Ap.

[0047] Furthermore, the vehicle light fixture 10 illuminates an additional range HPa below the cutoff line CL of the passing light fixture LP, near the projection optical axis Ap, with the driving light distribution pattern HP. Therefore, when the vehicle light fixture 10 switches from the passing light distribution to the driving light distribution, it is easy to visually confirm that the light distribution has been switched, and visibility at a distance is improved.

[0048] Furthermore, the vehicle light fixture 10 has an upper lens member 15 which includes an upper incident portion 21 into which light from the upper light source 11 is incident, an upper first reflective surface 22 which reflects the light incident therefrom, an upper second reflective surface 23 which reflects the light reflected there toward the upper exit surface 25, and an upper bottom reflective surface 27 which reflects a portion of the light reflected there toward the upper exit surface 25. The lower light incident surface 28 is provided between the upper second reflective surface 23 and the upper bottom reflective surface 27. As a result, the vehicle light fixture 10 can appropriately direct the light guided to the upper lens member 15 toward the upper exit surface 25 by each reflective surface (22, 23, 27), and the lower light incident surface 28 can be provided facing the upper exit surface 25 without impairing their functions.

[0049] The vehicle light fixture 10 has an upper bottom reflective surface 27 that is tilted such that the middle position in the width direction is located at the lowest point, and it is displaced upward as it moves towards both outer sides in the width direction. As a result, the vehicle light fixture 10 can actively brighten the area around the projection light axis Ap, which is easily noticeable.

[0050] The vehicle light fixture 10 includes a low beam unit 18 that emits light from the upper emission surface 25 of the upper lens member 15 to form a passing light distribution pattern LP, a high beam unit 19 that emits light from the lower emission surface 33 of the lower lens member 16 which serves as a lower light source to form a driving light distribution pattern HP, and a projection lens 17 that projects light from both units (18, 19). The upper lens member 15 has an upper incidence section 21 into which light from the upper light source 11 is incident, an upper first reflection surface 22 that reflects the light incident therefrom, an upper second reflection surface 23 that reflects the light reflected there toward the upper emission surface 25, an upper bottom reflection surface 27 that reflects a portion of the light reflected there toward the upper emission surface 25, and a lower light incidence surface 28 that faces the upper emission surface 25 and incident a portion of the light emitted from the lower emission surface 33. The lower light incident surface 28 is provided between the upper second reflective surface 23 and the upper bottom reflective surface 27. As a result, the vehicle lamp 10 can form a driving light distribution pattern HP that extends below the cutoff line CL in the passing light distribution pattern LP, and it is easy to secure the amount of light that proceeds directly from the lower lens member 16 to the projection lens 17, thereby appropriately forming the driving light distribution pattern HP. Furthermore, the vehicle lamp 10 can appropriately direct the light guided to the upper lens member 15 to the upper emission surface 25 by each reflective surface (22, 23, 27), and the lower light incident surface 28 can be provided facing the upper emission surface 25 without impairing these functions.

[0051] The vehicle light fixture 10 has a lower light source section comprising a lower light source 12 and a lower lens member 16 provided with a lower emission surface 33. Therefore, the vehicle light fixture 10 can appropriately control the light from the high beam unit 19 with a simple configuration and appropriately form the driving light distribution pattern HP.

[0052] Therefore, the vehicle light fixture 10 of Embodiment 1 according to the present disclosure can emit a portion of the light from the high beam unit 19 from the upper emission surface 25 of the upper lens member 15 of the low beam unit 18, thereby forming a driving light distribution pattern HP with a desired light distribution.

[0053] Although the vehicle lighting device of this disclosure has been described above based on Embodiment 1, the specific configuration is not limited to Embodiment 1, and changes or additions to the design are permitted as long as they do not deviate from the gist of the invention as described in each claim of the patent.

[0054] In the above-described embodiment 1, the low-beam unit 17 was provided with five upper light sources 11, and the high-beam unit 18 was provided with four lower light sources 12. However, the number of each light source can be set as appropriate, and the configuration is not limited to the above-described embodiment 1.

[0055] Furthermore, in the above-described embodiment 1, the upper lens member 15 has an upper incident portion 21, an upper first reflective surface 22, an upper second reflective surface 23, an upper bottom reflective surface 27, and an upper exit surface 25, with a lower light incident surface 28 provided between the upper second reflective surface 23 and the upper bottom reflective surface 27. However, the upper lens member 15 may have other configurations as long as it has a lower light incident surface 28 that faces the upper exit surface 25 and allows a portion of the light emitted from the lower exit surface 33 to be incident, and forms a passing light distribution pattern LP, and is not limited to the configuration of embodiment 1 described above. For example, the upper lens member 15 may have an upper reflective surface that reflects light incident from the upper incident portion 21, and an upper bottom reflective surface 27 that reflects a portion of the light reflected there toward the upper exit surface 25, with a lower light incident surface 28 provided between the upper reflective surface and the upper bottom reflective surface 27. Even with such a configuration, the light guided to the upper lens member 15 can be appropriately directed toward the upper exit surface 25 by the upper reflective surface and the upper bottom reflective surface 27, and the lower light incident surface 28 can be provided facing the upper exit surface 25 without impairing their functions. [Explanation of Symbols]

[0056] 10 Vehicle lighting fixture 11 Upper light source 12 Lower light source (constituting the lower light source section as an example) 15 Upper lens member 16 Lower lens member (constituting the lower light source section as an example) 17 Projection lens 18 Low beam unit 19 High beam unit 21 Upper incident section 22 Upper first reflective surface 23 Upper second reflective surface 25 Upper exit surface 27 Upper bottom reflective surface 28 Lower light incident surface 33 Lower exit surface Ao Exit light axis Ap Projection light axis CL Cut-off line HP Light distribution pattern for driving LP Light distribution pattern for passing

Claims

1. A low-beam unit that emits light from the upper emission surface of the upper lens member to form a passing light distribution pattern, A high beam unit that emits light from the lower emission surface of the lower light source to form a light distribution pattern for driving, It comprises a projection lens that projects light from the low beam unit and light from the high beam unit, The upper lens member has a lower light incident surface that faces the upper emission surface and allows a portion of the light emitted from the lower emission surface to be incident on it. The vehicle lamp is characterized in that the lower light source unit has its own emitted optical axis inclined with respect to the projection optical axis of the projection lens, and the lower emitted surface is directed toward the lower light incident surface.

2. The vehicle lamp according to claim 1, characterized in that the lower light source is located below the projection light axis.

3. The vehicle light fixture according to claim 1, characterized in that the light distribution pattern for driving illuminates in the vicinity of the projection light axis and below the cutoff line of the passing light distribution pattern.

4. The upper lens member has an upper incident portion into which light from an upper light source is incident, an upper reflective surface that reflects the light incident from the upper incident portion, and an upper bottom reflective surface that reflects a portion of the light reflected by the upper reflective surface toward the upper output surface. The vehicle light fixture according to claim 1, characterized in that the lower light incident surface is provided between the upper reflective surface and the upper bottom reflective surface.

5. The upper reflective surface has an upper first reflective surface that reflects light incident from the upper incident portion, and an upper second reflective surface that reflects the light reflected by the upper first reflective surface toward the upper exit surface. The vehicle lamp according to claim 4, characterized in that the upper bottom reflective surface reflects a portion of the light reflected by the upper second reflective surface toward the upper emission surface.

6. The vehicle light fixture according to claim 4, characterized in that the upper bottom reflective surface is inclined such that the intermediate position in the width direction is located at the lowest point, and it displaces upward as it moves toward both outer sides in the width direction.

7. A low-beam unit that emits light from the upper emission surface of the upper lens member to form a passing light distribution pattern, A high beam unit that emits light from the lower emission surface of the lower light source to form a light distribution pattern for driving, It comprises a projection lens that projects light from the low beam unit and light from the high beam unit, The upper lens member has an upper incident portion for receiving light from an upper light source, an upper reflective surface for reflecting light incident from the upper incident portion, an upper bottom reflective surface for reflecting a portion of the light reflected by the upper reflective surface toward the upper output surface, and a lower light incident surface that faces the upper output surface and receives a portion of the light emitted from the lower output surface. A vehicle light fixture characterized in that the lower light incident surface is provided between the upper reflective surface and the upper bottom reflective surface.

8. The upper reflective surface has an upper first reflective surface that reflects light incident from the upper incident portion, and an upper second reflective surface that reflects the light reflected by the upper first reflective surface toward the upper exit surface. The vehicle lamp according to claim 7, characterized in that the upper bottom reflective surface reflects a portion of the light reflected by the upper second reflective surface toward the upper emission surface.

9. The vehicle light fixture according to any one of claims 1 to 8, characterized in that the lower light source section comprises a lower light source and a lower lens member provided with the lower emission surface.

Images