JP2010123301A - Vehicle headlamp unit and vehicle headlamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle headlamp unit for realizing a wide range and ideal light distribution of a vehicle headlamp by enhancing utilization efficiency of light of an LED light source. <P>SOLUTION: Out of light from the LED light source 12, light which is reflected by a first reflecting surface 16 and has directly entered into a projection lens 14 is irradiated in an effective area from the projection lens as headlamp light distribution for vehicle. Furthermore, out of light from the LED light source, light which has entered into the projection lens from the first reflecting surface through a second reflecting surface 20 is irradiated in the effective area from the projection lens as headlamp light distribution for vehicle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle headlamp unit and a vehicle headlamp, and more particularly to a vehicle headlamp unit using an LED light source as a light source, and a vehicle headlamp equipped with the vehicle headlamp unit. About.

  Conventionally, in the field of vehicle headlamps, two reflecting surfaces are used, light from an LED light source is reflected by one reflecting surface, and the other light is reflected on a basic light distribution pattern formed by this reflected light. A vehicle headlamp that forms a predetermined light distribution pattern by superimposing an additional light distribution pattern formed by reflected light from a surface is known (for example, Patent Document 1).

  The vehicle headlamp unit 100 described in Patent Document 1 shown in FIG. 9 includes a projection lens 110 arranged so that the unit optical axis Ax and the optical axis thereof coincide with each other, and the optical axis thereof is relative to the unit optical axis Ax. The LED light source 120 disposed in the orthogonal direction, the dome-shaped reflector 130 disposed so as to cover the LED light source 120, and the LED light source 120 are disposed on the side of the LED light source 120, and a cut-off forming surface is provided at the tip edge thereof. The plate-shaped light control member 140 is formed. The reflector 130 is formed with a first reflecting surface 150 and a second reflecting surface 160, and a third reflecting surface 170 is formed on the upper surface of the light control member 140.

  According to the vehicle headlamp unit 100, the light from the LED light source 120 is totally reflected by the first reflecting surface 150 and transmitted through the projection lens 110, thereby forming a basic light distribution pattern, and the LED light source 120. The additional light distribution pattern is formed by reflecting the light from the second reflecting surface 160 and transmitting it through the projection lens 110.

  Further, according to the vehicle headlamp unit 100, the light reflected from the first reflecting surface 150 is reflected by the third reflecting surface 170 toward the projection lens 110, so that the light control member 140 is originally used. Light that should be wasted after being shielded is effectively used for beam irradiation.

The first reflecting surface 150 is provided on the front side of the optical axis Ax with respect to the LED light source 120, and condenses and reflects the light from the LED light source 120 toward the front in the optical axis Ax direction toward the optical axis Ax. Further, the second reflecting surface 160 extends from the front end portion of the first reflecting surface 150 in the optical axis Ax direction so as to be inclined toward the optical axis Ax toward the front in the optical axis Ax direction.
Japanese Patent No. 4080780

  However, in the vehicle headlamp unit 100 of Patent Document 1, the light reflected by the second reflecting surface 160 and projected by the projection lens 110 is shifted to a position lower than the horizontal line, that is, the front of the vehicle. Since it irradiates the outside of an effective area as a light distribution, it is difficult to say that the light from the LED light source is effectively used.

  Further, when light distribution is performed using the projection lens 110, internal reflection occurs in the projection lens 110, so that the spread of the light distribution is limited to a maximum of 50 degrees on one side, and it is difficult to realize a further wide light distribution. Met.

  The present invention has been made in view of such circumstances, and provides a vehicle headlamp unit that can increase the light use efficiency of an LED light source and obtain a wide light distribution. With the goal.

  In order to achieve the above object, the present invention provides a vehicle headlamp including an LED light source, a projection lens, a first reflecting surface, a second reflecting surface, a third reflecting surface, and a fourth reflecting surface. The first reflecting surface has a substantially spheroidal surface having a first focal point in the vicinity of the LED light source and a second focal point in the vicinity of the focal point of the projection lens, or a similar elliptical cross section. The second reflecting surface is formed by a flat surface extending horizontally toward the LED light source at a ridge line that forms a vehicle light / dark boundary line at the focal point of the projection lens, and the third reflecting surface is formed by a curved surface. A substantially elliptical ellipsoid having a second focal point in the space between the focal point of the projection lens and the projection lens and having a first focal point in the vicinity of the LED light source, or a curved surface having a similar elliptical cross section, The fourth reflecting surface The third reflecting surface has the first focal point as a focal point, and is formed by a rotating paraboloid having a unit optical axis as an axis, or a curved surface having a similar parabola in cross section, and is reflected by the third reflecting surface. The vehicle headlamp unit is characterized in that the reflected light is reflected forward in the optical axis direction without passing through the projection lens.

  According to the present invention, the light directly incident on the projection lens from the first reflecting surface among the light from the LED light source is irradiated to an area effective as a vehicle headlamp light distribution. Moreover, the light reflected from the first light-reflecting surface through the second light-reflecting surface out of the light from the LED light source is incident on the projection lens and is irradiated to an area effective as a vehicle headlamp light distribution. . The remaining light of the LED light source is reflected from the third reflecting surface through the fourth reflecting surface, and is reflected toward the front in the optical axis direction without passing through the projection lens.

  Thus, according to this invention, the light utilization efficiency of a LED light source can be improved by providing a 3rd reflective surface and a 4th reflective surface. Further, since the light reflected by the third reflecting surface and the fourth reflecting surface is reflected toward the front in the optical axis direction without passing through the projection lens, a wide light distribution can be obtained, By superimposing this light distribution on the light distribution obtained by the first reflecting surface and the second reflecting surface, the light from the LED light source can be irradiated to an effective area as a headlamp light distribution for the vehicle without waste. be able to.

  In order to achieve the above object, the present invention is a vehicle headlamp unit including an LED light source, a projection lens, a first reflecting surface, a second reflecting surface, and a third reflecting surface. The first reflecting surface is formed by a curved surface having a substantially spheroidal surface having a first focal point in the vicinity of the LED light source and a second focal point in the vicinity of the projection lens, or a similar elliptical cross section, The second reflecting surface is formed by a flat surface extending horizontally toward the LED light source at a ridge line that forms a vehicle light / dark boundary line at the focal point of the projection lens, and the third reflecting surface is formed of the LED light source. Formed by a rotating paraboloid having a focal point in the vicinity and a curved surface having a cross section of a similar parabola around the unit optical axis, and the light from the LED light source is guided in the optical axis direction without passing through the projection lens. Reflect towards the front To provide a vehicle headlamp unit according to claim.

  According to the present invention, the light directly incident on the projection lens from the first reflecting surface among the light from the LED light source is irradiated to an area effective as a vehicle headlamp light distribution. Moreover, the light reflected from the first light-reflecting surface through the second light-reflecting surface out of the light from the LED light source is incident on the projection lens and is irradiated to an area effective as a vehicle headlamp light distribution. . Then, the remaining light of the LED light source is reflected by the third reflecting surface, and is reflected toward the front in the optical axis direction without passing through the projection lens.

  Thus, according to this invention, the light utilization efficiency of an LED light source can be improved by providing a 3rd reflective surface. In addition, since the light reflected by the third reflecting surface is reflected toward the front in the optical axis direction without passing through the projection lens, a wide light distribution can be obtained. By superimposing the light distribution obtained by the first reflection surface and the second reflection surface, it is possible to irradiate the light from the LED light source to an effective area as the vehicle headlamp light distribution without waste.

  According to the vehicle headlamp unit of the present invention, 90% or more of the light from the LED light source can be effectively used, and the light use efficiency is very excellent compared with the conventional vehicle headlamp unit. Can be realized.

  In addition, in the vehicle headlamp unit using the conventional projection lens, the light that can spread the light distribution only up to 50 degrees with respect to the optical axis is transmitted to the third reflecting surface and the fourth reflecting surface. It can be expanded up to 90 degrees by the surface (Claim 1) and the third reflecting surface (Claim 2).

  Furthermore, since the vehicle headlamp unit of the present invention can secure a large space near the LED light source, it is possible to dispose a heat sink structure for heat dissipation near the LED light source, and the depth in the unit optical axis direction Can be made compact.

  According to the present invention, it is preferable that the first reflecting surface and the third reflecting surface are integrally formed. Thereby, the number of parts of the reflector which comprises a reflective surface can be reduced.

  Furthermore, in order to achieve the above object, the present invention provides a vehicular headlamp characterized by being configured by the vehicular headlamp unit of the present invention. According to the vehicle headlamp of the present invention, it is possible to increase the light use efficiency of the LED light source and to obtain a wide light distribution.

  As described above, according to the vehicle headlamp unit and the vehicle headlamp according to the present invention, the light use efficiency of the LED light source can be increased and a wide light distribution can be obtained.

  Hereinafter, preferred embodiments of a vehicle headlamp unit and a vehicle headlamp according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a longitudinal sectional view showing a configuration of a vehicle headlamp unit 10 according to a first embodiment.

  The vehicle headlamp unit 10 includes an LED light source 12, a projection lens 14, a reflector 18 having a first reflecting surface 16, a shade 22 having a second reflecting surface 20, a reflector 26 having a third reflecting surface 24, And a reflector 30 having a fourth reflecting surface 28 and the like.

  The LED light source 12 is fixed to the upper surface of the heat sink 32 for heat dissipation via the substrate 13, and the optical axis thereof is disposed at a right angle with respect to the direction perpendicular to the unit optical axis Ax. . The projection lens 14 is attached to a lamp casing (not shown) so that its optical axis matches the unit optical axis Ax.

  As shown in FIG. 2, the first reflecting surface 16 is disposed above the LED light source 12. The first reflecting surface 16 has a first focal point F1 in the vicinity of the LED light source 12, and a substantially spheroidal surface having a second focal point F2 in the vicinity of the rear focal point of the projection lens 14 as shown in FIG. It is formed by a curved surface with a elliptical cross section. That is, the first reflecting surface 16 is formed into a substantially spheroidal surface having a line segment connecting F1 and F2 as an axis, or a curved surface having a similar elliptical cross section.

  The second reflecting surface 20 is formed on the upper surface of the shade 22, and is formed by a plane in which a ridge line 15 that forms a vehicle light / dark boundary line at the focal point F of the projection lens 14 extends horizontally toward the LED light source 12. Yes.

  On the other hand, the third reflecting surface 24 is disposed near the projection lens 14 above the shade 22. As shown in FIG. 2, the third reflecting surface 24 has a second focal point F4 in the space between the focal point F of the projection lens 14 and the projection lens 14, and a first focal point F3 in the vicinity of the LED light source 12. It is formed by a spheroidal surface or a curved surface having a similar elliptical cross section. That is, the third reflecting surface 24 is formed as a substantially rotating ellipsoid Q indicated by a broken line in FIG. 2 or a curved surface having a similar elliptic cross section with the line segment connecting F3 and F4 as the axis P. In addition, by disposing F4 between the focal point F of the projection lens 14 and the projection lens 14 in this way, the heat sink 32 can be extended to the projection lens 14 side. Efficiency can be improved.

  The fourth reflecting surface 28 is disposed near the projection lens 14 below the shade 22. The fourth reflecting surface 28 has a second focal point F4 on the third reflecting surface 24 as a focal point F5, and is a rotating paraboloid having a unit optical axis Ax as an axis, or a curved surface having a similar parabola in cross section. Is formed. The fourth reflecting surface 28 is attached to a position where the light reflected by the third reflecting surface 24 is reflected from the lower side of the projection lens 14 toward the front in the unit optical axis Ax direction without passing through the projection lens 14. It has been.

  The LED light source 12 of the embodiment is provided with an LED chip that emits white light suitable for a vehicle headlamp (headlamp), but when used for an auxiliary headlamp (fog lamp). May emit other colored light. Moreover, although the aspherical lens which can diffuse the light from the LED light source 12 more largely is applied to the projection lens 14 of the embodiment, it may be a spherical lens.

  Next, the operation of the vehicle headlamp unit 10 according to the first embodiment will be described.

  First, of the light from the LED light source 12, the light reflected by the first reflecting surface 16 and directly incident on the projection lens 14 is irradiated from the projection lens 14 to an area effective as a beam distribution for passing the vehicle headlamp. Is done. FIG. 3 shows a light distribution by only the first reflecting surface 16, and according to this light distribution, the range is about 8 to 11 degrees downward from the horizontal line (0 on the vertical axis). It can be seen that an area having an extent of about 40 degrees on one side in the left-right direction is irradiated by the first reflecting surface 16. Note that an area of about 11 degrees on the lower side of the light distribution is a range of about 8 degrees on one side in the left-right direction.

  Next, of the light from the LED light source 12, the light incident on the projection lens 14 from the first reflecting surface 16 through the second reflecting surface 20 is passed through the vehicle headlamp from the projection lens 14 and is distributed by a beam. As an effective area. FIG. 4 shows the light distribution by the first reflecting surface 16 and the second reflecting surface 20, and according to this light distribution, the range is about 2 to 5 degrees downward from the horizontal line. It can be seen that an area having a spread of about 36 degrees on one side in the left-right direction is irradiated by the first reflecting surface 16 and the second reflecting surface 20.

  Then, the remaining light of the LED light source 12 is reflected from the third reflecting surface 24 through the fourth reflecting surface 28, and goes forward from the lower side of the projection lens 14 in the optical axis Ax direction without passing through the projection lens 14. And reflected. FIG. 5 shows the light distribution by the third reflecting surface 24 and the fourth reflecting surface 28. According to this light distribution, the range is about 9 degrees downward from the horizon, It can be seen that an area having an extent of about 73 degrees in the direction and about 33 degrees in the right direction is irradiated by the third reflecting surface 24 and the fourth reflecting surface 28. The area shown in FIG. 5 is an area effective as a vehicle headlamp light distribution. It can also be seen that the optical axis of the light reflected by the fourth reflecting surface 28 is tilted to the left with respect to the front.

  Thus, according to the vehicle headlamp unit 10 of the first embodiment, in addition to the first reflecting surface 16 and the second reflecting surface 20, the third reflecting surface 24 and the fourth reflecting surface. By providing 28, the light utilization efficiency of the LED light source 12 can be improved.

  In addition, since the light reflected by the third reflecting surface 24 and the fourth reflecting surface 28 is reflected forward in the optical axis Ax direction without passing through the projection lens 14, the area shown in FIG. (An area having a spread of about 73 degrees in the right direction and about 33 degrees in the right direction), and the light distribution shown in FIG. 5 is the first distribution shown in FIG. Since the light distribution by the reflecting surface 16 and the light distribution by the second reflecting surface 20 shown in FIG. 4 are superposed, the light from the LED light source 12 is radiated to an effective area as a vehicle headlamp light distribution without waste. be able to.

  On the other hand, according to the vehicle headlamp unit 10, 90% or more of the light from the LED light source 12 can be used effectively, and the light is very excellent compared to the conventional vehicle headlamp unit. Can be used.

  Further, in the vehicle headlamp unit 100 using the conventional projection lens 110 shown in FIG. 9, the light that can be expanded only up to 50 degrees with respect to the unit optical axis Ax is maximized. Can be expanded to 90 degrees (about 73 degrees in FIG. 5).

  Furthermore, since the vehicular headlamp unit 10 of the embodiment can secure a large space in the vicinity of the LED light source 12, it is in the vicinity of the LED light source 12 as shown in FIGS. The heat sink 32 can be disposed at a position entering the front side of the optical axis Ax, and the depth in the unit optical axis Ax direction can be made compact.

  In the case of a vehicle headlamp that uses two or more vehicle headlamp units 10, 10, the interval between the light emitting areas of the vehicle headlamp units 10, 10 is required to be within 15 mm. It is done. It is difficult to dispose the vehicle headlamp units 10 and 10 close to each other by a structure such as a holding member for fixing the projection lens 14 or a heat sink 32 for radiating heat from the LED light source 12. However, by using the vehicular headlamp unit 10 of the embodiment, the standard requirement of the interval of 15 mm can be satisfied regardless of the arrangement of the vehicular headlamp unit.

  In the embodiment, the first reflective surface 16 and the third reflective surface 24 are configured separately, but the first reflective surface 16 and the third reflective surface 24 are close to each other. These may be integrally formed. Thereby, the number of parts of the reflector which comprises the reflective surfaces 16 and 24 can be reduced.

  Further, in order to make effective use of the light from the LED light source 12, that is, as shown in FIG. The lengths of the upper end 18A of 18 and the upper end 26A of the reflector 26 are set. Further, the length of the upper end portion 18A of the reflector 18 is determined by the taking-in angle of the projection lens 14.

  Further, the length of the upper end portion 26 </ b> A of the reflector 26 is set to such a length that the light reflected by the third reflecting surface 24 is not blocked by the second reflecting surface 20. Furthermore, the position of the reflector 30 is set to a position where the light distribution shown in FIG. 5 can be obtained. Further, the length of the lower end portion 18B of the reflector 18 is set by the effective light range of the LED light source 12, but the lower end of the reflector 18 is prevented so that light rays from the LED light source 12 do not leak from between the heat sink 32 and the light source 12. The portion 18B may extend so as to contact the upper surface of the heat sink 32.

  On the other hand, by making the shape of the heat sink 32 so as to be embedded under the shade 22 as shown in FIG. 7, the heat dissipation area of the heat sink 32 is increased, so that the heat dissipation rate of the LED light source 12 can be increased. And durability is improved.

  And according to the vehicle headlamp comprised by the vehicle headlamp unit 10 of embodiment, the effect similar to the vehicle headlamp unit 10, ie, the light utilization efficiency of the LED light source 12, is improved. In addition, it is possible to obtain an effect that a wide light distribution can be obtained.

  FIG. 8 is a longitudinal sectional view showing the configuration of the vehicle headlamp unit 50 according to the second embodiment, which is the same as the vehicle headlamp unit 10 according to the first embodiment shown in FIG. Or, similar members will be described with the same reference numerals.

  8 includes an LED light source 12, a projection lens 14, a reflector 18 having a first reflecting surface 16, a shade 22 having a second reflecting surface 20, and a third reflecting surface 52. The vehicle headlamp unit 50 shown in FIG. It is comprised from the reflector 54 etc. which have.

  Here, the configuration and operation of the first reflecting surface 16 and the second reflecting surface 20 are the same as those shown in FIGS. That is, the light distribution formed by the first reflecting surface 16 is the same as the light distribution shown in FIG. 3, and the light distribution formed by the first reflecting surface 16 and the second reflecting surface 20. The distribution is the same as the light distribution shown in FIG. Therefore, here, the configuration, operation, and effect of the third reflecting surface 52 will be described.

  The third reflecting surface 52 is disposed above the shade 22 and closer to the projection lens 14. The third reflecting surface 52 has a focal point F6 in the vicinity of the LED light source 12, and is formed by a rotating paraboloid about the unit optical axis Ax or a curved surface having a similar parabola in cross section. The third reflecting surface 52 reflects the light from the LED light source 12 from above the projection lens 14 toward the front in the unit optical axis Ax without passing through the projection lens 14.

  According to the vehicle headlamp unit 50, the light utilization efficiency of the LED light source 12 can be increased by providing the third reflecting surface 52. Further, since the light reflected by the third reflecting surface 52 is reflected forward in the unit optical axis Ax direction without passing through the projection lens 14, the light distribution distribution similar to the light distribution shown in FIG. As with the vehicle headlamp unit 10 of the first embodiment, a wide light distribution can be obtained. Further, since the light distribution by the third reflecting surface 52 is superimposed on the light distribution obtained by the first reflecting surface 16 and the second reflecting surface 20, the light from the LED light source 12 is transmitted to the front of the vehicle. It is possible to irradiate an area effective as a lighting distribution without waste.

  The above-described embodiment is merely an example in all respects. The present invention is not construed as being limited to these descriptions. The present invention can be implemented in various other forms without departing from the spirit or main features thereof.

The longitudinal cross-sectional view which showed the structure of the vehicle headlamp unit of 1st Embodiment Explanatory drawing which showed the rotation ellipsoid of the vehicle headlamp unit shown in FIG. 1 with the broken line Explanatory drawing which showed light distribution by only the 1st reflective surface Explanatory drawing which showed the light distribution by the 1st reflective surface and the 2nd reflective surface Explanatory drawing which showed the light distribution by the 3rd reflective surface and the 4th reflective surface Explanatory drawing showing a configuration for effectively using the light of the LED light source Explanatory drawing showing another form of heat sink The longitudinal cross-sectional view which showed the structure of the vehicle headlamp unit of 2nd Embodiment. A longitudinal sectional view showing the structure of a conventional vehicle headlamp unit

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Vehicle headlamp unit, 12 ... LED light source, 14 ... Projection lens, 16 ... 1st reflective surface, 18 ... Reflector, 20 ... 2nd reflective surface, 22 ... Shade, 24 ... 3rd reflective surface , 26 ... reflector, 28 ... fourth reflecting surface, 30 ... reflector, 32 ... heat sink, 50 ... vehicle headlamp unit, 52 ... third reflecting surface, 54 ... reflector

Claims (4)

A vehicle headlamp unit comprising an LED light source, a projection lens, a first reflecting surface, a second reflecting surface, a third reflecting surface, and a fourth reflecting surface,
The first reflecting surface is formed by a curved surface having a substantially spheroidal surface having a first focal point in the vicinity of the LED light source and a second focal point in the vicinity of the focal point of the projection lens, or a similar elliptical cross section,
The second reflecting surface is formed by a plane that extends horizontally toward the LED light source with a ridge line that forms a vehicle light / dark boundary line at the focal point of the projection lens,
The third reflecting surface has a substantially spheroidal surface having a second focal point in a space between the focal point of the projection lens and the projection lens and having a first focal point in the vicinity of the LED light source, or a similar elliptical cross section. Formed by the curved surface
The fourth reflecting surface has the first focal point in the third reflecting surface as a focal point, and is formed by a rotating paraboloid having a unit optical axis as an axis, or a curved surface having a similar parabola as a cross section, The vehicle headlamp unit, wherein the light reflected by the third reflecting surface is reflected forward in the optical axis direction without passing through the projection lens. A vehicle headlamp unit comprising an LED light source, a projection lens, a first reflecting surface, a second reflecting surface, and a third reflecting surface,
The first reflecting surface is formed by a curved surface having a substantially spheroidal surface having a first focal point in the vicinity of the LED light source and a second focal point in the vicinity of the focal point of the projection lens, or a similar elliptical cross section,
The second reflecting surface is formed by a plane that extends horizontally toward the LED light source with a ridge line that forms a vehicle light / dark boundary line at the focal point of the projection lens,
The third reflecting surface has a focal point in the vicinity of the LED light source, and is formed by a rotating paraboloid having a unit optical axis as an axis, or a curved surface having a similar parabola in cross section, and the light from the LED light source. Is reflected toward the front in the direction of the optical axis without passing through the projection lens.   The vehicle headlamp unit according to claim 1 or 2, wherein the first reflecting surface and the third reflecting surface are integrally formed.   A vehicular headlamp comprising the vehicular headlamp unit according to claim 1.

Images