JP5444046B2 - Vehicle headlamp - Google Patents

Description

  The present invention relates to a vehicular headlamp, and more particularly to a vehicular headlamp that forms a low beam (passing beam) light distribution pattern by a plurality of optical units that use a semiconductor light emitting element as a light source.

  Conventionally, the thing of the structure shown in FIGS. 12-16 is proposed for this kind of vehicle headlamp.

  12 includes a combination of a plurality of projector-type optical units 100 to 102 and a reflector-type optical unit 103 arranged in parallel to each other, and each arrangement formed by each of the optical units 100 to 103 is provided. By superimposing the light pattern, a low beam (passing beam) light distribution pattern having a horizontal cutoff line on the opposite lane side of the vertical reference line V and an oblique cutoff line on the traveling lane side is formed.

  Specifically, a projector type optical unit 100 to 102 forms a horizontal cutoff line, an oblique cutoff line, and a high illumination area near both cutoff lines, and a reflector type optical unit 103 forms a wide irradiation area. (For example, refer to Patent Document 1).

  Further, in FIG. 13, a plurality of projector-type optical units 110 to 113 are arranged at a predetermined angle with respect to each other, and a curved path is formed by combining respective light distribution patterns formed by the respective optical units 110 to 113. A light distribution pattern is formed.

  In this case, each of the optical units 110 to 113 has substantially the same light distribution pattern with respect to the respective optical axes Z110 to Z113, and the light amount control of each light distribution pattern formed with a predetermined pitch is performed. By performing each independently, only the position of the hot zone can be changed without changing the irradiation range (see, for example, Patent Document 2).

  Further, in FIG. 14, a plurality of projector-type optical units 120 to 124 are rotatably held by a bracket 125, and the irradiation direction of irradiation light by each of the optical units 120 to 124 that rotates according to the traveling state of the vehicle. And AFS that changes the irradiation range following (see, for example, Patent Document 3).

  In FIG. 15, a plurality of optical units 132 to 136 each having a light emitting element 130 are provided with a cylindrical lens 137 extending in the vehicle width direction in front of the reflector 131. A light distribution pattern is formed by the irradiation light from 136 through the cylindrical lens 137.

  At this time, among the optical units 132 to 136, the optical units 134 to 136 arranged in parallel to each other form a horizontal cut-off line, an oblique cut-off line, and a high illumination area in the vicinity of both cut-off lines, and have a predetermined angle with each other. An irradiation region that extends greatly toward the traveling lane is formed by the optical units 132 and 133 that are disposed (see, for example, Patent Document 4).

  16 includes a plurality of projector-type optical units 140 to 143 and a plurality of reflector-type optical units 144 and 145, and is arranged in the front direction of the vehicle. 143 forms a horizontal cut-off line and an oblique cut-off line of the light distribution pattern, and a horizontal cut-off line is formed by reflector-type optical units 144 and 145 arranged at a predetermined angle toward the side in the vehicle width direction. A horizontally long light distribution pattern extending from the lower vicinity to the outside in the vehicle width direction is formed.

  As a result, even a vehicular lamp having a shape that wraps around the rear of the vehicle body can be reduced in thickness, and the light used from each optical unit is not shielded by the adjacent optical unit, so that the light use efficiency is improved. And a light distribution pattern having a wide irradiation range can be formed (see, for example, Patent Document 5).

JP 2008-13014 A JP 2006-172829 A JP 2007-5182 A JP 2005-294176 A JP-A-2005-141919

  Vehicle headlights that use semiconductor light-emitting elements as light sources (particularly vehicle headlights that form low-beam light distribution patterns) use reflectors and lenses to satisfy the light distribution standards specified by laws and regulations. Thus, light distribution control of the emitted light from the semiconductor light emitting element is performed.

  For example, a so-called projector-type optical unit that performs light distribution control by a combination of a reflector and a lens has a thickness (thickness in the depth direction when mounted on a vehicle) restriction due to a reduction in the thickness of the headlamp. The distance is limited, and only a range of about 40 ° left and right in front of the vehicle can be irradiated. Therefore, although it is suitable for illuminating a distant area in front of the vehicle with high illuminance, it cannot be said to be suitable for lateral illumination in front of the vehicle. On the other hand, a so-called reflector type optical unit that performs light distribution control mainly by a reflector can illuminate a wide range, but it is difficult to form each cut-off line of the light distribution pattern.

  Therefore, the vehicle headlamp described in Patent Document 1 realizes a headlamp that takes advantage of each advantage by combining the projector-type optical units 100 to 102 and the reflector-type optical unit 103. is there.

  However, since the headlamp having such a configuration is composed of optical units having different shapes of a projector type and a reflector type, some people feel uncomfortable in the design when viewing the headlamp from the front of the vehicle. In addition, since the light source is directly visible when the reflector-type optical unit 103 is not lit, when the light source is composed of a semiconductor light emitting element and a phosphor, the yellow portion of the phosphor color is conspicuous and the appearance is poor. End up. In other words, the headlamp is poor in design.

  In the vehicle headlamp described in Patent Document 2, each of the plurality of optical units 110 to 113 constituting the headlamp has substantially the same light distribution pattern. It is impossible to form elbows and various cut-off lines peculiar to each other. Further, since the optical units 110 to 113 are arranged at a predetermined angle, the light from the optical units 110 to 113 is forwardly rightward with respect to the upper limit vertical line VU-VD, for example, 10 °. , 15 °, 20 °, 30 °, and 40 °.

  For this reason, a low-luminance region is generated in an intermediate portion connecting the respective light distribution patterns formed by the irradiation lights of the optical units 110 to 113 arranged adjacent to each other. The luminance unevenness in which the high luminance region and the low luminance region are alternately present is obtained.

  Moreover, since the vehicle headlamp described in Patent Document 3 changes the irradiation direction and irradiation range of the irradiation light according to the traveling state of the vehicle, it is impossible to always irradiate a wide range.

  In addition, the vehicle headlamp described in Patent Document 4 includes a plurality of optical units 132 to 136 each formed of a reflector 131 including a light emitting element 130 and a single cylindrical lens 137. It is impossible to individually control the light distribution of the emitted light from 132 to 136 with one cylindrical lens 137, and a desired light distribution pattern as a headlamp cannot be freely obtained.

  Further, since the vehicle headlamp described in Patent Document 5 is composed of projector-type optical units 140 to 143 and reflector-type optical units 144 and 145, it has poor design as in Patent Document 1. It becomes a thing.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to configure a plurality of optical units having substantially the same shape, each of which has a semiconductor light emitting element as a light source, and to extend the vehicle in the left-right direction over a wide range. For low-profile vehicles with excellent design that can be irradiated with irradiation light with high brightness and low brightness unevenness, and can clearly form elbows and various cut-off lines peculiar to the passing beam distribution pattern It is to provide a headlamp.

  In order to solve the above-mentioned problems, the invention described in claim 1 of the present invention is a vehicle headlamp in which at least three optical units are accommodated in a lamp chamber formed by a front lens and a housing. Each of the plurality of optical units is mounted with a light source module including a light source and a projection lens for controlling the optical path of light emitted from the light source and projecting it forward, and an electronic component. A flexible substrate in which a first reinforcing plate and a second reinforcing plate, which are independent of each other in heat conduction, are pasted on the back surfaces of the mounting portion and the mounting portion of the electronic component, respectively, and a position below the flexible substrate The light source module mounting portion is thermally connected to the heat sink via the first reinforcing plate, and the electronic component mounting portion is connected to the second reinforcing plate and the Heat conduction with the heat sink is suppressed by a heat shield plate disposed between the optical sink and the three optical units in the vehicle width direction of the vehicle, and the adjacent optical units in the vehicle width direction of the vehicle. It is characterized by being arranged obliquely so as to form a predetermined angle with respect to.

  According to a second aspect of the present invention, in the first aspect, the light shielding plate and the heat sink are provided on the heat sink, and a wavy portion having a wavy cross section provided on the light shielding plate. In addition, a concave-convex portion having a concave-convex shape in which the concave and convex portions are alternately continuous is fitted.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the optical units adjacent to each other are positioned such that the optical unit located on the side of the vehicle is located on the center side of the vehicle. The irradiation range in the vehicle width direction is not narrower than that of the optical unit.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the light source modules of the optical units adjacent to each other in the plurality of optical units are arranged in the vehicle width direction. The angles formed with respect to each other are substantially the same.

  The vehicle headlamp of the present invention includes a plurality of optical units housed in a lamp chamber formed by a front lens and a housing, a light source module and an electronic component mounted thereon, and a light source module mounting portion and an electronic component. A light source module comprising: a flexible board in which a first reinforcing plate and a second reinforcing board, which are independent of each other and having good heat conduction, are pasted on the back surfaces of the mounting parts; and a heat sink positioned below the flexible board. The mounting portion is thermally connected to the heat sink via the first reinforcing plate, and the electronic component mounting portion is thermally conductive with the heat sink by the heat shield plate disposed between the second reinforcing plate and the heat sink. This optical unit constitutes a low beam light source unit for forming a low beam light distribution pattern, and the light source modules of the optical units adjacent to each other are formed. Lumpur each other was and arrangement as the irradiation range of the vehicle width direction is not smaller than the optical unit the optical unit is positioned at the center side positioned on measuring how side of the vehicle at a predetermined angle.

  As a result, due to the heat dissipation effect on the light source module, the temperature rise during lighting is suppressed and the decrease in light emission efficiency is reduced, so that it is possible to secure a predetermined amount of irradiation light and suppress deterioration of the light source over time. It has become possible to maintain reliability.

  In addition, the heat shielding effect on the electronic component allows the electronic component to be operated under good electrical characteristics while protecting the electrical characteristics from changes due to heat, and also to ensure reliability.

  Furthermore, a vehicle headlamp having good visibility for the driver, no dazzling for the oncoming vehicle, small and thin, and excellent design can be provided.

1 is a perspective view of an embodiment according to the present invention. Explanatory drawing of a light source module. It is explanatory drawing of a light source. It is explanatory drawing of a flexible substrate. It is explanatory drawing of a heat sink. It is explanatory drawing of a heat shield. It is a perspective view of an optical unit. It is sectional drawing of an optical unit. It is a projection figure by an optical unit. It is a figure which shows the passing light distribution pattern projected on the screen. It is explanatory drawing of an optical unit. It is explanatory drawing of a prior art example. It is explanatory drawing of a prior art example. It is explanatory drawing of a prior art example. It is explanatory drawing of a prior art example. It is explanatory drawing of a prior art example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 11 (the same parts are given the same reference numerals). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is a perspective view of a vehicle headlamp (hereinafter abbreviated as a headlamp) according to the present invention. The headlamp described below is a headlamp located on the left side of a left-handed vehicle of a left-handed vehicle among a pair of headlamps mounted on the left and right sides of the vehicle.

As shown in FIG. 1, the basic structure of the headlamp 80 is a light source unit 4 for a low beam and a traveling beam (high beam) in a lamp chamber 3 formed of an airtight space surrounded by a housing 1 and a front lens 2. A light source unit 5 is provided. Among these, the low beam light source unit 4 is composed of four optical units including a first optical unit 4a, a second optical unit 4b, a third optical unit 4c, and a fourth optical unit 4d. The light source unit 5 is composed of one optical unit including a fifth optical unit 5a.
The

  Then, a passing beam light distribution pattern is formed by the passing beam light source unit 4 configured by the four optical units 4a to 4d, and the traveling beam light distribution unit 5 configured by one optical unit 5a is used. A light pattern is formed.

  Among them, each of the optical units 4a to 4d includes a light source module 10a to 10d including a light source group 12 including a plurality of light sources (four light sources 12a to 12d in the present embodiment), and an electronic component other than the light source module 10 and the light source module. 21 and the like, a flexible flexible substrate 20 mounted thereon, a heat sink 30 that dissipates heat generated by the light emission of the semiconductor light emitting element serving as the light emission source of each of the light sources 12a to 12d, 30 and a heat shield plate 40 that sandwiches the flexible substrate 20.

  As shown in FIG. 2 (cross-sectional view), the light source module 10 includes a light source group 12 including a plurality of light sources (four light sources 12 a to 12 d in the present embodiment) mounted on one end side of the flexible substrate 20. An optical system is configured by a combination with a projection lens 13 that controls the optical path of light emitted from the light source group 12 and projects it forward (in the direction of the front lens 2).

  For example, as shown in FIG. 3, each of the light sources 12 a to 12 d constituting the light source group 12 uses the semiconductor light emitting element 11 as a light emitting source, and encapsulates the resin 15 so as to cover the semiconductor light emitting element 11 mounted on the flexible substrate 20. Is arranged. In the present embodiment, for example, an LED element is used as the semiconductor light emitting element 11, and a translucent resin such as an epoxy resin or a silicone resin is used as the sealing resin 15.

  In addition, when obtaining light (for example, white light) having a color tone different from that of the light source light of the semiconductor light emitting element 11 as the irradiation light of the headlamp, one or more kinds of phosphors are dispersed in the translucent resin. The semiconductor light emitting element 11 may be resin-sealed with the sealing resin 15 to be formed.

  Returning to FIG. 2, the projection lens 13 includes a light exit surface 17 b and a back surface 18 b facing the light exit surface, and both opposing surfaces are three-dimensional free-form surfaces and are made of glass or transparent resin. A reflective surface 18a is formed on the back surface 18b by a reflective film 18 formed by depositing a reflective material such as aluminum by a vapor deposition method or the like, and reflects light from the semiconductor light emitting element 11. The semiconductor light emitting element 11 is provided in a substantially central recess of the back surface 18b, and the central recess is a light incident surface 19 on which the reflective film 18 is not formed.

  At this time, the light emitting surface 17b and the back surface 18b facing each other are formed so as to obtain predetermined light distribution characteristics. The back surface 18b is a curved surface that curves toward the light exit surface 17b as it is away from the central recess, and is a three-dimensional free-form surface that has a different curvature in a cross section that passes through the center. The light exit surface 17b is also a three-dimensional free-form surface having different curvatures in an orthogonal cross section passing through the center. At this time, in FIG. 1, directions in which the curvatures of the back surfaces 18b of the optical units 4a, 4b, 4c, and 4d are large (directions in which the curvature is small) are substantially the same direction.

  As shown in FIG. 4 (a is a front view and (b) is a side view), the flexible substrate 20 is mounted with the light source module 10 on one end side, and the light source module on the other end side. An electronic component 21 such as a connector is mounted on the same surface as the surface on which 10 is mounted.

  The surface of the flexible substrate 20 opposite to the region where the light source module 10 is mounted and the surface opposite to the region where the electronic component 21 is mounted have good thermal conductivity such as metal or ceramic, respectively. Rigid reinforcing plates 22 and 23 made of various materials are affixed independently of each other via a heat conductive adhesive or the like. The reinforcing plates 22 and 23 have the functions of deformation protection of the flexible substrate 20 and heat transfer / heat dissipation.

  As shown in FIG. 5 (a is a front view and (b) is a cross-sectional view taken along the line AA of FIG. 5A), the heat sink 30 has a flat plate-like main body portion 31 made of a metal material and one of the main body portions 31. The projection 32 provided on the end side of the projection and the concavo-convex portion 33 provided on the same side as the projection 32 on the other end side. The protrusion 32 has a flat upper surface 32a, and the concavo-convex portion 33 is provided with concave portions 33a and convex portions 33b alternately and continuously, and has a concavo-convex cross section.

  As shown in FIG. 6 ((a) is a front view and (b) is a cross-sectional view taken along the line BB of (a)), the heat shield plate 40 has a flat plate shape and annularly surrounds the window hole 41a and the window hole 41a. A frame body portion 41 composed of a frame 41b, and a wavy portion 42 having a concave portion 42a on one surface side and a bent portion 42c having a convex portion 42b on the other surface side, provided with a predetermined interval, and having a wavy cross section. It consists of a flat plate-like connecting portion 43 that integrally connects the frame portion 41 and the wave-like portion 42 at one end side. That is, the other end side opposite to the connection portion 43 on one end side is a cutout portion 44, and the overall shape of the heat shield plate 40 is substantially U-shaped.

  Therefore, the optical units 4 a to 4 d have the structure shown in FIGS. 7 and 8 by the flexible substrate 20, the heat sink 30, and the heat shield plate 40. 7 is a perspective view, and FIG. 8 is a cross-sectional view.

  The heat shield plate 40 is disposed on the heat sink 30 in a state in which the protruding portion 32 of the heat sink 30 protrudes from the window hole 41 a and the corrugated portion 42 is fitted to the uneven portion 33 of the heat sink 30. The flexible substrate 20 positions the reinforcing plate 22 on the light source module 10 side on the upper surface 32a of the protrusion 32 of the heat sink 30 and the reinforcing plate 23 on the electronic component 21 side on the waved portion 42 of the heat shield plate 40. The intermediate portion 24 between the light source module 10 and the corrugated portion 42 is pressed against the heat sink 30 by the holding portion 41 c of the annular frame 41 b of the heat shield plate 40.

  In this state, the reinforcing plate 22 on the light source module 10 side of the flexible substrate 30 is fixed to the upper surface 32a of the protrusion 32 of the heat sink 30 by a fixing member (not shown) such as a screw, and the electronic component 21 side of the flexible substrate 30 The reinforcing plate 23 and the heat shield plate 40 are fastened to the heat sink 30 together with a fixing member (not shown) such as a screw.

  In the vehicular lamp having such a structure, a heat dissipation system and an optical system will be described below.

  In the heat dissipation system, the heat generated when the semiconductor light emitting element that is the light source of the light sources 12 a to 12 d of the light source module 10 is turned on is generated by the reinforcing plate 22 and the heat sink 30 that are attached to the flexible substrate 30 on the opposite side of the light source module 10. Are sequentially conducted and dissipated from the heat sink 30 to the outside. As a result, the temperature rise at the time of lighting of the semiconductor light emitting element is suppressed, and a decrease in light emission efficiency is reduced, thereby making it possible to secure a predetermined amount of irradiation light and to suppress deterioration of the semiconductor light emitting element over time. It is also possible to maintain reliability.

  At the same time, heat conducted from the semiconductor light emitting element to the heat sink 30 is prevented from being transferred to the reinforcing plate 23 by the heat shield plate 40, and the electronic component 21 mounted on the side of the flexible substrate 30 opposite to the reinforcing plate 23. Temperature rise is suppressed. As a result, the electronic component 21 can be operated under good electrical characteristics while being protected from changes in electrical characteristics due to heat, and reliability can be ensured.

  On the other hand, regarding the optical system, the positional relationship between the light sources 12a to 12d constituting the light source group 12 of the light source modules 10a to 10d of the respective optical units 4a to 4d and the projection lens 13 and the optical path formation by them are shown in FIGS. This will be described with reference to (projected view). The light source modules 10a to 10d of the optical units 4a to 4d are designed so as to form different light distribution patterns, as will be described later. Therefore, in the present description, among the four optical units 4a to 4d, the light distribution pattern projected on the virtual vertical screen 60 disposed at the position 25m ahead of the headlamp has a first line having at least three cut lines. The optical module 10a of the first optical unit 4a to be the light distribution pattern 51a is used.

  As shown in FIG. 2, a predetermined arrangement is provided in the central portion of the projection lens 13 on the side where the reflection film 18 is provided, of the projection lens 13 having three-dimensional free-form surfaces 16 and 17 that are curved convexly toward each other. A plurality of light sources 12a to 12d are disposed, and the light incident surface 19 of the projection lens 13 is located in the vicinity of the light sources 12a to 12d so as to cover the light sources 12a to 12d. The light sources 12a to 12d are arranged substantially linearly in the same direction X as the direction in which the curvature of the back surface 18b of the projection lens 13 is large.

  Therefore, the light emitted from the light source 12 a enters the projection lens 13 from the light incident surface 19. For example, the light L2 emitted in the front optical axis direction of the light source 12a is emitted as it is without being substantially reflected by the light emitting surface 17b. Of the light directed in the direction (oblique direction) inclined from the front optical axis direction of the light source 12a, the light L1 reflected by the light exit surface 17b is reflected by the light exit surface 17b and then travels toward the back surface 18b. Go ahead. When a light ray incident on the three-dimensional free-form surface 17 that forms an interface with the atmosphere having a refractive index smaller than that of the projection lens 13 is an angle of incidence θ with respect to the three-dimensional free-form surface 17 is greater than a critical angle, the three-dimensional free surface The curved surface 17 becomes a total reflection surface and is totally reflected.

  The light beam L1 returning to the projection lens 13 side is guided through the projection lens 13 toward the three-dimensional free-form surface 16 side, reaches the reflection surface 18a by the reflection film 18 via the three-dimensional free-form surface 16, and is reflected by the reflection surface 18a. It is reflected and returns to the projection lens 13 side again through the three-dimensional free-form surface 16.

  The light beam L1 that has returned to the projection lens 13 is guided through the projection lens 13 toward the three-dimensional free-form surface 17, and is refracted by the light-exiting surface 17b with the three-dimensional free-form surface 17 serving as a light-exiting surface 17b. 13 is emitted to the outside. A portion A of the first light distribution pattern 51a as shown in FIG. 9 is formed by the emitted light beam L1.

  In this way, the light beam L1 emitted from the light source 12a and incident on the projection lens 13 is guided through the projection lens 13 and emitted to the outside from the light exit surface 17a of the projection lens 13, and on the virtual vertical screen 60. Two reflections of total reflection by the total reflection surface 17a of the projection lens 13 and reflection by the reflection surface 18a of the reflection film 18 and 1 by the light emission surface 17b of the projection lens 13 in the optical path to the predetermined position A. Times of refraction are performed.

  That is, the optical path of the light beam L1 is controlled by the direction of the minimal surface of the arrival point of the light beam L1 on each of the total reflection surface 17a and the light emission surface 17b of the projection lens 13 and the reflection surface 18a of the reflection film 18.

  Then, as the predetermined light distribution pattern, for example, the light emitting surface 17b and the back surface 18b are divided into minimum surfaces and controlled so as to form the first light distribution pattern 51a shown in FIG. 9 on the virtual vertical screen 60, By connecting these minimal surfaces, the shape of the projection lens 13 is determined.

  As shown in FIG. 10A, the light source module 10b of the second optical unit 4b, the light source module 10c of the third optical unit 4c, and the light source module 10d of the fourth optical unit 4d are each similarly processed. The optical design is made so that the second light distribution pattern 51b, the third light distribution pattern 51c, and the fourth light distribution pattern 51d are formed.

  Therefore, when comparing each of the light distribution patterns 51a to 51d, each of the light distribution patterns 51a to 51d has a horizontal cutoff line CL1 and an oblique cutoff line CL2 on the traveling lane side of the vertical reference line V, and the vertical reference line V. It has a horizontal cut-off line CL3 on the opposite lane side, and the irradiation range in the vehicle width direction of the vehicle is the widest light distribution pattern 51d by the fourth optical unit 4d, and hereinafter the light distribution pattern 51c by the third optical unit 4c. The light distribution pattern 51b by the second optical unit 4b and the light distribution pattern 51a by the first optical unit 4a become wider in this order.

  That is, the irradiation range with respect to the vehicle width direction of each optical unit is set to a wider range as the optical unit is located on the vehicle side side of the headlamp.

  As described above, the irradiation range is set mainly by changing the curvature in the vehicle width direction of the three-dimensional free-form surface 17 that also serves as two optical functional surfaces of the total reflection surface and the light emission surface of the projection lens. The light source module having a wider range has a larger curvature of the light exit surface 17b. That is, the curvature in the vehicle width direction of the three-dimensional free-form surface 17 of each light source module is set to be larger as the light source module of the optical unit located on the vehicle side of the headlamp.

  The light source modules 10a to 10d of the optical units 4a to 4d are arranged such that adjacent light source modules are maintained at a predetermined angle, and the optical axes of the light source modules 10a to 10d are set to Za to Zd. Then, Za is 0, Zb is α, Zc is 2α, and Zd is 3α toward the side in the width direction of the vehicle with respect to the direction of the center line Z along the longitudinal direction of the vehicle. (See FIG. 1).

  That is, the light source module 10a of the optical unit 4a faces the front of the vehicle, and the light source modules adjacent to each other among the light source modules 10a to 10d of the optical units 4a to 4d all face the measuring side in the width direction of the vehicle. The angle α is maintained.

  Moreover, the irradiation light which forms the center side edge part of each light distribution pattern 51a-51d which light source modules 10a-10d of each optical unit 4a-4d form is the arrangement | positioning direction and irradiation range of each light source module 10a-10d. Based on the difference, the light source modules 10a to 10d are set to have substantially the same angle with respect to the direction of the center line Z of the vehicle.

  Thereby, the center side end portions of the light distribution patterns 51 a to 51 d formed on the virtual vertical screen 60 are positioned on the substantially straight line V <b> 1 parallel to the vertical reference line V.

  Further, the light distribution patterns 51a to 51d are arranged such that at least the height of the horizontal cutoff line CL3 coincides with the lower side of the horizontal reference line H so that the irradiation light on the opposite lane side of the vertical reference line V does not dazzle the oncoming vehicle. Has been adjusted. Here, the term “match” refers to 1.5 ° on the opposite lane side with respect to the vertical reference line V (0 °) on the virtual vertical screen 20 arranged at a position 25 m ahead of the headlamp of the present invention, 2 When the luminous intensity of the headlamps is measured at intervals of 0.05 ° in the height direction on each straight line of 5 ° and 3.5 °, the height at which the G value obtained from each measurement value becomes the maximum matches. It means to do.

Here, the G value is used as a definition of the cut-off line, and represents the inclination at each point when the vertical section of the screen luminous intensity is cut, and is represented by the following expression.
G = (log E _β- log E _{(β + 0.1 °)} ) β: vertical angle (°)
The larger G, the clearer the cutoff line.

  In this way, the light distribution pattern 51 for the passing beam is formed by synthesizing the light distribution patterns 51a to 51d formed by the light source modules 10a to 10d of the optical units 4a to 4d. As can be seen from the passing beam light distribution pattern 51 in this case, the light source module 10b of the second optical unit 4b covers the first light distribution pattern 51a formed by the light source module 10a of the first optical unit 4a. The light distribution module 51c of the third optical unit 4c is located so as to cover the second light distribution pattern 51b formed of the light source module 10b of the second optical unit 4b. The light source module 10d of the fourth optical unit 4d covers the third light distribution pattern 51c formed by the light source module 10c of the third optical unit 4c. The light distribution modules 51a to 10d of the optical units 4a to 4d are located. Without feel brightness difference due to the difference in the irradiation range of the driver, with no discomfort to the driver, wide irradiation region, it is possible to achieve good headlamp visibility.

  The light distribution patterns 51a to 51d formed by the light source modules 10a to 10d of the optical units 4a to 4d are all horizontal cutoff lines CL1 and oblique cutoff lines CL2 on the traveling lane side of the vertical reference line V, and the vertical reference. The line V has a horizontal cut-off line CL3 on the opposite lane side and is located on substantially the same line for each of the cut-off lines CL1 to CL3. Therefore, the light distribution pattern 51 for the passing beam composed of the combined light distribution pattern is provided for each cut-off line CL1. Each of .about.CL3 is clearly formed, and in particular, on the opposite lane side of the vertical reference line V, the upper limit of the orientation pattern is set at a predetermined position, and it is possible to realize a headlamp that does not dazzle the oncoming vehicle. It has become.

  The fifth optical unit 5a constituting the traveling beam light source unit 5 is a projection-type optical unit like the optical units 4a to 4d, and surrounds the light source 70 and the light source 70 as shown in FIG. A reflector 71 having a reflection surface arranged, a projection lens 72 positioned in front of the reflector 71, and a lens holder 73 that supports the projection lens 72 are provided. As a result, a traveling beam light distribution pattern is formed.

  The fifth optical unit 5a is located closer to the center of the vehicle than the other optical units 4a to 4d constituting the headlamp, and its optical axis Ze is the direction of the center line Z along the longitudinal direction of the vehicle. It faces substantially the same direction (see FIG. 1).

  The light distribution pattern shown in FIG. 10B shows the light distribution pattern formed by the headlamp located on the right side when viewed from the driver.

  In this case, the five optical units are not shown, but the optical unit in the above-mentioned headlamp is configured symmetrically with respect to the center line Z along the vehicle front-rear direction. A traveling beam light source unit composed of an optical unit is located, and a low beam light source unit composed of four optical units is located on the side of the traveling beam light source unit.

  Then, by combining the light distribution patterns 52a to 52d formed by the respective optical units constituting the low beam light source unit, the low beam light distribution pattern 52 is formed and travels by the optical unit constituting the travel beam light source unit. A beam distribution pattern (not shown) is formed.

  By the way, in the description so far, the low beam light source unit for forming the low beam light distribution pattern is composed of four optical units. However, the number of the light source units is not necessarily limited to this, and a plurality of optical units may be used. By configuring, implementation of the present invention becomes possible.

  Of the light distribution patterns formed by the plurality of optical units constituting the low beam light source unit, a flat light distribution pattern having no oblique cut-off line is not necessarily required. In other words, at least one of the plurality of light distribution patterns may be a light distribution pattern having an oblique cut-off line. Thereby, it becomes possible to satisfy the predetermined light distribution standard of the vehicular headlamp.

  As described above, the vehicle headlamp according to the present invention passes in the optical system by a plurality of optical units in which a projection-type light source module is formed by a light source having a semiconductor light-emitting element as a light source and a projection lens. A low beam light source unit for forming a beam light distribution pattern was constructed.

  Each optical unit forms a desired light distribution pattern by changing the curvature of the surface formed by the three-dimensional free-form surface of the projection lens of the light source module constituting the optical unit, and adjacent light sources are also zy optical units. Aligned with each other while maintaining a predetermined equiangular angle

  As a result, the thickness of each optical unit can be reduced, so that adjacent optical units can be arranged at a narrow interval and at a large angle, and the left and right sides of the vehicle can be arranged while being thin and small and projecting. A vehicular headlamp that can irradiate light with irradiation light with high brightness and little brightness unevenness over a wide range has been realized.

  In addition, a plurality of projection type optical modules are arranged at equal angles, respectively, and the projection lens of each optical module is set to have a larger curvature as it is positioned laterally from the center of the vehicle. Excellent design is achieved by regular arrangement of the optical unit and each light source module projection lens.

  Furthermore, the irradiation range of the optical unit located at the most central side of the vehicle is narrowed to increase the luminous intensity, and the irradiation range is widened as it is located on the outer side so that the light beam is diffused. At the same time, each optical unit is formed. The cut-off lines of the respective light distribution patterns are positioned on substantially the same line. Therefore, the passing beam light distribution pattern obtained by synthesizing the light distribution patterns formed by the respective optical units is not dazzled for the oncoming vehicle and has good visibility in a distant and wide range for the driver.

  Also, in the heat dissipation system, each optical unit is composed of a flexible substrate, a heat sink and a heat shield plate, and the heat shield plate is protruded from the projection of the heat sink through its window hole, and the corrugated portion is fitted to the uneven portion of the heat sink. Arranged on the heat sink in a state, the flexible substrate, the reinforcing plate on the light source module side is positioned on the upper surface of the protrusion of the heat sink, and the reinforcing plate on the electronic component side is positioned on the waved portion of the heat shield plate, and The intermediate part between the light source module and the waved part is pressed against the heat sink by the holding part of the annular frame of the heat shield plate.

  Therefore, the heat generated when the semiconductor light emitting element of the light source module is turned on is sequentially conducted to the reinforcing plate and the heat sink attached to the opposite side of the flexible substrate to the light source module, and dissipated from the heat sink to the outside. As a result, the temperature rise at the time of lighting of the semiconductor light emitting element is suppressed, and a decrease in light emission efficiency is reduced, thereby making it possible to secure a predetermined amount of irradiation light and to suppress deterioration of the semiconductor light emitting element over time. It is also possible to maintain reliability.

  At the same time, the heat conducted from the semiconductor light emitting element to the heat sink is suppressed by the heat shield to the reinforcing plate, and the temperature rise of the electronic component mounted on the side of the flexible board opposite to the reinforcing plate is suppressed. The As a result, the electronic component can be operated under good electrical characteristics while being protected from changes in electrical characteristics due to heat, and reliability can be ensured.

DESCRIPTION OF SYMBOLS 1 ... Housing 2 ... Front lens 3 ... Light chamber 4 ... Light source unit for low beam (low beam) 4a ... 1st optical unit 4b ... 2nd optical unit 4c ... 3rd optical unit 4d ... 4th optical unit 5 Light source unit for traveling beam 5a 5th optical unit 10 Light source module 10a, 10b, 10c, 10d ... Light source module 11 ... Semiconductor light emitting element 12 ... Light source group 12a, 12b, 12c, 12d ... Light source 13 ... Projection lens 14 ... Substrate 15 ... Sealing resin 16 ... Three-dimensional free-form surface 17 ... Three-dimensional free-form surface 17a ... Total reflection surface 17b ... Light exit surface 18 ... Reflection film 18a ... Reflection surface 18b ... Back surface 19 ... Light incident surface 20 ... Flexible substrate 21 Electronic component 22 Reinforcing plate 23 Reinforcing plate 24 Intermediate portion 26 Reflecting film 26a Reflecting surface 30 Toe sink 31 ... Main body 32 ... Protruding part 32a ... Upper surface 33 ... Uneven part 33a ... Concave part 33b ... Convex part 40 ... Heat shield plate 41 ... Frame body part 41a ... Window hole 41b ... Ring frame 41c ... Holding part 42 ... Wave-like part 42a ... Concave part 42b ... Convex part 42c ... Bending part 43 ... Connection part 44 ... Notch part 51 ... Passing beam light distribution pattern 51a ... First light distribution pattern 51b ... Second light distribution pattern 51c ... Third light distribution Pattern 51d ... Fourth light distribution pattern 52 ... Passing beam light distribution pattern 52a ... First light distribution pattern 52b ... Second light distribution pattern 52c ... Third light distribution pattern 52d ... Fourth light distribution pattern 60 ... Virtual vertical screen 70 ... Light source 71 ... Reflector 72 ... Projection lens 73 ... Lens holder 80 ... Vehicle headlamp

Claims (4)

A vehicle headlamp comprising at least three optical units housed in a lamp chamber formed by a front lens and a housing,
Each of the plurality of optical units is mounted with a light source module including a light source and a projection lens that controls the optical path of the light emitted from the light source and projects the light forward, and an electronic component. And a flexible substrate in which the first reinforcing plate and the second reinforcing plate, which are independent of each other, are attached to the back surfaces of the mounting parts of the electronic component, and a heat sink positioned below the flexible substrate. The light source module mounting portion is thermally connected to the heat sink via the first reinforcing plate, and the electronic component mounting portion is disposed between the second reinforcing plate and the heat sink. Heat conduction with the heat sink is suppressed by the heat shield,
The three optical units are arranged obliquely in the vehicle width direction of the vehicle so that adjacent optical units form a predetermined angle with respect to the vehicle width direction. light.   The light shielding plate and the heat sink include a corrugated portion having a wavy cross section provided on the light shielding plate, and an uneven portion having a concave and convex shape in which the cross section provided on the heat sink is alternately continuous with concave portions and convex portions. The vehicle headlamp according to claim 1, wherein the vehicle headlamp is fitted.   The adjacent optical units are such that the irradiation range in the vehicle width direction of the optical unit located on the side of the vehicle is not narrower than the optical unit located on the center of the vehicle. Item 3. A vehicle headlamp according to Item 2.   4. The angle between the light source modules of the optical units adjacent to each other in the plurality of optical units is substantially the same with respect to the vehicle width direction. 5. Vehicle headlamps.

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