JP3972998B2 - Vehicle headlamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicular headlamp that employs, as a light source, a discharge lamp or the like in which a light source for a sub beam and a main beam having different light distribution patterns cannot be installed close to each other.
[0002]
[Prior art]
Conventionally, a so-called light source-driven vehicle headlamp has, as shown in FIGS. 13 and 14, for example, a reflector 100 in which a rotary parabolic reflecting surface is formed on an inner surface and a lower reflector and an upper reflector 101 at a substantially horizontal center. The light source is divided into the side reflector 102 and a single light source 103 such as a single filament or HID is arranged in front of the side reflector 102, and the focal point F1 of the upper reflector 101 and the focal point F2 of the lower reflector 102 are arranged in the front-rear direction on the same optical axis L. When the “sub-beam” is irradiated by moving the light source 103 in the front-rear direction on the optical axis L, as shown in FIG. When the “main beam” is irradiated to the intermediate position of the focal point F2 of the side reflector 102, as shown in FIG. Stopping the focus F1 position, it was composed to be able to switch to a predetermined light distribution pattern by light distribution P2 by light distribution P1 and the lower reflector 102 by the upper reflector 101.
[0003]
[Problems to be solved by the invention]
However, in the conventional light source-driven vehicle headlamp configured as described above, during sub-beam irradiation, as shown in FIG. 16A, the light distribution P1 by the upper reflector 101 and the lower reflector 102 are used. Although a predetermined light distribution pattern can be formed by polymerizing the light distribution P2, the light distribution P2 of the lower reflector 102 is near the center of the irradiation screen as shown in FIG. Is far away from the H line, i.e., the front side of the vehicle, and distant visibility deteriorates. Also in the light distribution P1 of the upper reflector 101, the optical axis direction and main beam at the time of sub-beam irradiation Since the optical axis direction during irradiation is the same direction, if the optical axis direction during sub-beam irradiation is set to 0.57 ° D on the V-line, the optical axis during main beam irradiation is also 0.57 °. D had a problem that the distance visibility was deteriorated and the distant visibility deteriorated.
[0004]
The present invention has been made in view of the above problems, and is configured such that all or a part of the lower reflector can be moved with respect to the optical axis, and a light source is provided on the movable lower reflector. To provide a light source-driven vehicle headlamp capable of forming a necessary light distribution pattern at the time of main beam irradiation by fixing and simultaneously moving both in the front-rear and up-down directions with respect to the optical axis. It is intended.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a vehicle headlamp according to the present invention has a rotary parabolic reflecting surface on the inner surface, an upper reflector having a focal point F1 at a substantially horizontal center, and a lower side having a focal point F2. a reflector formed by dividing into a reflector, in front of the reflector, the vehicle headlamp comprising wearing the discharge lamp as a light source, around the support shaft provided with said discharge lamp to a lower portion of the lower reflector The discharge lamp is integrally mounted on the lower reflector or a part of the lower reflector, and the discharge lamp can be freely moved in the front-rear and vertical directions together with all or part of the lower reflector. a light distribution pattern is rotated to form a driving mechanism of a light source switching the sub beam and a main beam, at the time of sub-beam irradiation, and the focus F2 of the focus F1 and the lower reflector of the upper reflector same Offset in the longitudinal direction to sandwich the light source on the optical axis L, at the time of main-beam irradiated Further, the light source causes slightly moved downward F of the optical axis, it is brought closer to the vicinity of the focal point F1 of the upper reflector, the lower The gist is that a part of the optical axis of the reflector or the lower reflector is directed upward .
[0006]
A discharge lamp may be integrally attached to the lower reflector or a part of the lower reflector, and may be configured to freely rotate in the front-rear and vertical directions together with the lower reflector or a part of the lower reflector. it can. Further, the lower reflector or a part of the lower reflector and the discharge lamp mounted integrally therewith may be configured to freely rotate around a support shaft formed at the lower part of the lower reflector. it can.
[0007]
The drive mechanism of the light source can be constituted by a cam that is operated by an actuator.
[0008]
According to the above configuration, the focal point F1 of the upper reflector and the focal point F2 of the lower reflector are shifted in the front-rear direction across the light source on the same optical axis in a state where the lower reflector is moved forward and upward. While the sub-beam is irradiated and the lower reflector is moved rearward and downward, the light source moves slightly below the optical axis L, and the main beam is irradiated close to the focal point F1 of the upper reflector. At this time, since the optical axis of the lower reflector is directed upward by the same angle as the movement range (rotation angle) of the lower reflector, the light distribution of the lower reflector rises to the vicinity of the center of the irradiation screen, and Distant visibility improves because the amount of light increases.
[0009]
The lower reflector is provided with a support shaft at the lower front end thereof, and supports the opening side so as to freely rotate in the vertical direction around the support shaft, and is driven through a cam at the lower portion. Due to the structure, the light source can be moved slightly lower than the light source position during sub-beam irradiation and the optical axis of the main beam can be set slightly upward during main beam irradiation, thus improving far visibility. be able to.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a vehicle headlamp according to the present invention will be described with reference to the drawings.
As shown in FIG. 1, the reflector 1 constituting the vehicle headlamp according to the present invention forms a rotating parabolic reflecting surface on the inner surface, and focuses the focal point F1 in the horizontal direction, that is, substantially at the center of the rotating parabolic reflecting surface. It is divided into an upper reflector 2 having a lower reflector 3 and a lower reflector 3 having a focal point F2, and a discharge lamp 4 serving as a light source G is mounted in front thereof. In the present embodiment, the upper reflector 2 is a reflection inclined downward to the horizontal line H on the left side of the vertical line V passing through the optical axis L in front view in order to form a predetermined light distribution P1 at the time of sub-beam irradiation. The surface 2a is extended so that the irradiation light in the roadside direction is not insufficient. Further, the lower reflector 3 is formed in a bowl shape as a whole below the upper reflector 2, and in the present embodiment, it extends downward from both sides of the vertical line V from the optical axis L and has a fan shape. The movable part 3 a divided into two parts is formed, and a fixed part 3 b formed above the movable part 3 a is formed so as to be integrally continuous below the upper reflector 2.
[0011]
The movable part 3a of the lower reflector 3 configured as described above is integrally formed with a reflector bottom 3c for attaching the discharge lamp 4 to the upper end including the optical axis L, and is fixed to the reflector bottom 3c. A socket 5 is mounted on the discharge lamp 4. The movable portion 3a of the lower reflector 3 is rotatably supported by a support shaft 7 via a bracket 6 formed in the lower portion thereof, and the opening side is moved back and forth within a predetermined range by a drive mechanism described later. The discharge lamp 4 can be moved up and down and in the vertical direction with respect to the optical axis L together with the movable portion 3a. It consists of.
[0012]
The focal point F1 of the upper reflector 2 and the focal point F2 of the lower reflector 3 sandwich the light source (light emitting part) G of the discharge lamp 4 on the same optical axis L during sub-beam irradiation (see FIG. 2A). When the main beam is irradiated (see FIG. 2 (b)), the light source G is moved slightly below the optical axis L and close to the focal point F1 of the upper reflector 2. It is made possible.
[0013]
As shown in FIG. 3, the movable part 3a of the lower reflector 3 is fixed to the lamp housing (not shown) side through arms 9 and 9 that are rotatably connected to a bracket 8 formed at the rear part. It is connected to an actuator 10 such as a rotary solenoid or a step motor provided, and tilted and rotated so that the opening side of the movable portion 3a is raised and lowered with the driving force of this actuator 10 around the support shaft 7 in the longitudinal and vertical directions. At the same time, the light source G position of the discharge lamp 4 is moved back and forth and up and down with respect to the optical axis L to form a light distribution pattern of “sub beam” and “main beam”.
[0014]
(1) At the time of irradiation of the sub beam “sub beam”, the movable portion 3a of the lower reflector 3 is supported in an upright posture as shown in FIG. The focal point F1 of the upper reflector 2 on the axis L and the focal point F2 of the lower reflector 3 are shifted in the front-rear direction, and as shown in FIG. 4, the light distribution P1 by the upper reflector 2 below the H line of the irradiation screen The light distribution P2 by the lower reflector 3 is superposed to form a sub-beam light distribution pattern.
[0015]
(2) At the time of irradiation of the main beam “main beam”, as shown in FIG. 2B, the movable portion 3a of the lower reflector 3 is inclined backward by θ degrees, and the light source G of the discharge lamp 4 is slightly moved along the optical axis L. While moving downward, the upper reflector 2 is brought close to the vicinity of the focal point F1. At this position, as shown in FIG. 5, a light distribution P1 is formed by the upper reflector 2 collected at the center of the irradiation screen, and the light distribution P1 by the movable portion 3a of the lower reflector 3 is superimposed on the light distribution P1. Light P2 is formed to obtain irradiation light with improved distance visibility. In addition, the lower reflector 3 forms light distributions P3 and P3 distributed to the left and right of the V line below the H line by the fixing portion 3b, and illuminates the road surface in front of the vehicle on the road side and the opposite lane side. It is made to get light. At this time, since the optical axis of the movable portion 3a of the lower reflector 3 is directed upward by the same angle as the rotation angle θ of the movable portion 3a, the amount of light in front of the vehicle is reduced, and the amount of light toward the far side is increased to visually recognize the distance. A main beam light distribution pattern with good properties can be formed.
[0016]
6 and 7 show a second embodiment of the present invention configured to be able to move the entire lower reflector.
In this embodiment, the reflector 11 is formed in a substantially bowl shape as a whole, and forms a rotary parabolic reflection surface on the inner surface thereof, and also in the horizontal direction, that is, approximately the center of the optical axis L of the rotary parabolic reflection surface. Are divided into an upper reflector 12 having a focal point F1 and a lower reflector 13 having a focal point F2. A discharge lamp 14 is mounted in front of the reflector 11, and a predetermined light distribution P1 at the time of sub-beam irradiation is formed by the upper reflector 12. In addition, the upper reflector 12 has a reflecting surface 12a extending downward to the horizontal line H on the left side of the vertical line V passing through the optical axis L in a front view, so that irradiation light toward the front side of the vehicle in the road side direction can be emitted. It is configured not to run out.
[0017]
The lower reflector 13 is completely divided below the upper reflector 12, and the entire lower reflector 13 is configured as a movable part. In the lower reflector 13 configured as described above, a reflector bottom portion 13a for attaching the discharge lamp 14 to the upper end including the optical axis L is integrally formed. The discharge lamp 14 fixed to the reflector bottom portion 13a The socket 15 is configured to be attached. The lower reflector 13 is rotatably supported by a support shaft 17 (rotation center O) via a bracket 16 formed at the lower end of the lower reflector 13, and an opening side of the lower reflector 13 is predetermined by an actuator (not shown). The discharge lamp 14 mounted on the lower reflector 13 can be moved up and down and up and down with respect to the optical axis L. It can be inclined and moved in the direction.
[0018]
According to the configuration as described above, at the time of “sub-beam” irradiation, the lower reflector 13 is supported in an upright posture as shown in FIG. 7A, and the same light is sandwiched between the light source G of the discharge lamp 14. The focal point F1 of the upper reflector 12 on the axis L and the focal point F2 of the lower reflector 13 are displaced in the front-rear direction, and a predetermined sub-beam light distribution pattern by the upper reflector 12 and the lower reflector 13 below the H line of the irradiation screen. Can be formed.
Further, at the time of irradiation of the “main beam”, the lower reflector 13 tilts backward by θ degrees and moves the light source G of the discharge lamp 14 slightly below the optical axis L, as shown in FIG. The upper reflector 12 is brought close to the vicinity of the focal point F1. At this position, as shown in FIG. 8, a light distribution P1 is formed by the upper reflector 12 condensed at the center of the irradiation screen, and a lower reflector 13 inclined upward by θ degrees so as to be superposed on the light distribution P1. The main beam light distribution pattern with good distance visibility can be formed by increasing the amount of light in the distance.
[0019]
FIG. 9 shows another embodiment relating to the driving method of the light source, and the difference from the first and second embodiments will be described.
In the embodiment of the present invention, a reflector bottom portion 23c for mounting the discharge lamp 24 is formed on the rear portion of the substantially bowl-shaped reflector 21 having a rotary parabolic reflection surface formed on the inner surface thereof. The reflector bottom 23c, to which the discharge lamp 24 is mounted, is configured to be inclined and moved while being inserted and removed in the front-rear direction within a predetermined range. In the embodiment of the present invention, the reflector 21 is divided into an upper reflector 22 having a focal point F1 and a lower reflector 23 having a focal point F2 in the horizontal direction, that is, substantially at the center of the rotary parabolic reflecting surface. The side reflector 23 is supported on the bulb holder 28 and is configured to move freely in the front-rear and up-down directions together with the reflector bottom 23c on which the discharge lamp 24 is mounted.
[0020]
That is, the valve holder 28 has a structure in which the lower reflector 23 is fixed to the upper portion of the main portion 28a, and the rotation center O is formed at the front end of the lower portion of the lower reflector 23 and closer to the opening. The discharge lamp holding portion 28b raised from its rear end is fixed to the reflector bottom portion 23c, and the discharge lamp 24 is inserted from the rear portion of the reflector 21 onto the optical axis L to be supported. In addition, the engagement edge 29 is further protruded rearward of the main body 28a. A cam 30 that is rotationally driven by an actuator (not shown) is engaged with the lower portion of the engagement edge 29. In the illustrated example, the cam 30 is formed by continuously forming a small-diameter portion R1 to a large-diameter portion R3 on the outer periphery by a variable-diameter portion R2, and the small-diameter portion R1 and the large-diameter portion R3 share a rotation center O. In addition, the arcuate length of both arcs is “R1 + R3 = 2R2”, the rotation angle A is approximately 180 degrees, and the rotation angle A can be displaced at the diameter-changed portion R2. Is set to move in the range of the rotation angle A in the front-rear and up-down directions. Therefore, as shown in FIG. 10 (a), in the arc range of the small diameter portion R1 and the large diameter portion R3 (the portion indicated by the arrow B), the valve holder 28 does not move even if the cam 30 rotates. Even if the valve holder 28 moves up and down in the circular arc range (the portion indicated by the arrow C) of the diameter-changed portion R2 that continues from R1 to the large-diameter portion R3, even if the cam 30 rotates beyond the set rotation angle, The support position of the discharge lamp 24 supported by the lamp is not changed any more (see FIG. 10B).
[0021]
The rear end side of the valve holder 28 is supported by the cam 30, and the rear end side is moved up and down by the cam 30 around the support shaft 27 that pivotally supports the front end side (rotation center O). The reflector bottom 23c and the discharge lamp 24 supported on the upper side can be inclined backward by a predetermined angle. Reference numeral 31 denotes an elastic body such as a spring that pulls and biases the rear end side of the engagement edge 29 downward, prevents the engagement edge 29 from being lifted with respect to the cam 30, and enables a smooth contact operation. This is to eliminate the influence of unstable elements due to vibration and other impacts on the reflector bottom 23c and the discharge lamp 24.
Thus, the engagement edge 29 of the valve holder 28 is placed on the small diameter portion R1 in the range where the rotation angle A of the cam 30 is approximately −130 ° (FIG. 9A) to −90 ° (FIG. 9B). , The reflector bottom 23c is moved rearward to support the discharge lamp 24 in the main beam irradiation posture, and the rotation angle A is approximately + 90 ° (FIG. 9 (c)) to + 135 ° (FIG. 9 (d)). ) In the front and rear range, the locking edge 29 of the bulb holder 28 is supported on the large-diameter portion R3, the reflector bottom 23c is moved forward, and the discharge lamp 24 is supported upright in the sub-beam irradiation posture. That is, the valve holder 28 is configured so as to be inclined and moved in the front-rear and up-down directions when the rotation angle A of the cam 30 is in the range of −90 ° to + 90 °. Thus, it is possible to improve the accuracy of the stop position of the valve holder 28 without increasing the accuracy of the rotation angle A of the cam 30.
[0022]
11 and 12 show another embodiment relating to a method for driving a light source, and only the parts different from the third embodiment will be described.
That is, the embodiment of the present invention does not use the elastic body 31 configured in the third embodiment, passes through the rotation center O of the cam 40 at the rear portion of the valve holder 38, and extends from the small diameter portion R1 side to the large diameter portion. A frame 39 having an upper and lower inner width corresponding to the maximum diameter D connecting the R3 side is formed, and two or three cams 30 detailed in the third embodiment are reversed (see FIG. In the example shown, two cams 40 are housed, fitted and sandwiched between the upper and lower edges of the frame 39, and the vertical movement range of the valve holder 38 is regulated by the cam 40 fixed to a predetermined portion, and the lift is prevented. It is configured to prevent. In this embodiment, the upper and lower edges of the frame 39 are formed with cutouts 39a and 39a for smooth rotation of the cams 40 that are joined together so as to be opposite to each other ( (See FIG. 12). With such a configuration, the friction of the cam 40 against the inner surface of the frame 39 formed on the valve holder 38 such as an elastic body is prevented, and the valve holder 38 can be smoothly operated.
[0023]
In the embodiment of the present invention, in the range where the rotation angle A of the cam 40 is approximately −130 ° (FIG. 11A) to −90 ° (FIG. 11B), the small-diameter portion R1 side is the side of the frame 39. By rotating to the upper edge side, the reflector bottom 33c is moved backward to support the discharge lamp 34 in the main beam irradiation posture, and the rotation angle A is changed from approximately + 90 ° (FIG. 11 (c)) to + 135 ° (FIG. 11). (D)) In the front and rear range, the large-diameter portion R3 side is moved to the upper edge side of the frame 39, and the reflector bottom portion 33c is moved forward to support the discharge lamp 34 upright in the sub-beam irradiation posture. Yes.
[0024]
Of course, in each embodiment of the present invention, it is possible to provide a shade around the discharge lamp so as to prevent the emission of excess illumination light toward the front upper side of the vehicle.
[0025]
【The invention's effect】
Since the vehicular headlamp according to the present invention is configured as described above, at the time of “main beam” irradiation in which the lower reflector is inclined and moved backward, the optical axis of the lower reflector is set to the rotational inclination angle of the reflector. Since it inclines upward by the same amount, the amount of light at the central portion of the irradiation screen can be increased, and a main beam light distribution pattern with excellent distance visibility can be formed.
In addition, the discharge lamp equipped with the lower reflector and the socket can be easily moved back and forth and up and down with a simple configuration, and the switching operation of the light distribution pattern can be performed with high accuracy. The effect obtained by is extremely great.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a first invention configured to be able to move a part of a lower reflector of a vehicle headlamp according to the present invention, and is a schematic front view with a front lens removed. FIG.
FIGS. 2A and 2B show an operating state of the lower movable reflector in the embodiment of the first invention, wherein FIG. 2A is a side sectional view of the state in which the lower reflector is erected forward, and FIG. It is a sectional side view in the state where the side movable reflector was inclined and moved backward by θ °.
FIG. 3 is a perspective view seen from the rear in the embodiment of the first invention.
FIG. 4 is an explanatory diagram showing a light distribution pattern during sub-beam irradiation according to the embodiment of the first invention.
FIG. 5 is an explanatory diagram showing a light distribution pattern during main beam irradiation in the embodiment of the first invention.
FIG. 6 is a schematic front view of a state in which a front lens is removed showing an embodiment of the second invention configured so that the entire lower reflector can be moved.
7A and 7B show an operating state of the lower movable reflector in the embodiment of the second invention, wherein FIG. 7A is a side sectional view of the state in which the lower reflector is erected forward, and FIG. It is a sectional side view in the state where the side movable reflector was inclined and moved backward.
FIG. 8 is an explanatory diagram showing a light distribution pattern during main beam irradiation according to the embodiment of the second invention.
FIG. 9 shows another embodiment of the drive device for the lower reflector, wherein (a) sets the cam rotation angle to −130 ° and tilts the lower reflector backward. The main part side sectional view showing the state (the state at the time of main beam irradiation), (b) is also the main part side sectional view of the state where the cam is rotated to a rotation angle of −90 °, and (c) is the cam rotation angle. Is a cross-sectional side view of the main part showing the state in which the lower reflector is erected forward with the angle set to + 90 ° (the state at the time of sub-beam irradiation), and (d) shows the state in which the cam is also rotated to a rotation angle of + 135 °. It is a principal part sectional side view shown.
FIGS. 10A and 10B show a configuration of a cam for driving a lower reflector, where FIG. 10A is a side view, and FIG. 10B is an explanatory diagram showing a change in radius depending on the rotation angle of the cam.
FIG. 11 shows still another embodiment of the lower reflector driving apparatus, wherein (a) sets the cam rotation angle to −130 ° and tilts the lower reflector backward. Fig. 4B is a sectional side view of the main part showing the state of the main beam irradiation, Fig. 5B is a side sectional view of the main part in the state where the cam is rotated to a rotation angle of -90 °; Cross-sectional side view of the principal part showing a state where the angle is set to + 90 ° and the lower reflector is raised and moved forward (state during sub-beam irradiation), (d) is a state where the cam is also rotated to a rotation angle of + 135 ° FIG.
FIG. 12 is an enlarged perspective view of a main part showing the structure of the frame.
FIG. 13 is a schematic front view showing a structure of a reflector configured in a conventional vehicle headlamp.
FIG. 14 is a cross-sectional side view of a main part showing the structure of a reflector that is also configured in a conventional vehicle headlamp.
FIG. 15 is a view showing a moving positional relationship of a light source with respect to a focal point of an upper reflector and a focal point of a lower reflector in a reflector similarly configured in a conventional vehicle headlamp, and FIG. A side sectional view and (b) are principal part side sectional views showing the time of main beam irradiation.
FIG. 16 is a view showing a light distribution pattern formed by a reflector similarly configured in a conventional vehicle headlamp. FIG. 16A is an explanatory diagram showing a light distribution pattern during sub-beam irradiation, and FIG. It is explanatory drawing which shows the light distribution pattern at the time of beam irradiation.
[Explanation of symbols]
1,11,21 Reflector 2,12,22 Upper reflector 3,13,23 Lower reflector 3c, 13c, 23c, 33c Reflector bottom part 4,14,24,34 Discharge lamp 5,15,25,35 Socket 6 Bracket 7 , 17, 27, 37 Support shaft 8 Bracket 9, 9 Connecting arm 10 Actuator 28 Valve holder 29 Engagement edge 30, 40 Cam 39 Frame O Rotation center G Light source L Optical axis θ Rotation angle F1 Upper reflector focus F2 Below Side reflector focal point V Vertical line H Horizontal line XY Before and after and up and down

Claims (1)

A rotary parabolic reflecting surface is formed on the inner surface, the reflector is divided into an upper reflector having a focal point F1 at a substantially horizontal center and a lower reflector having a focal point F2, and a light source is emitted in front of the reflector as a light source. In vehicle headlamps that are equipped with electric lights,
The discharge lamp is integrally mounted on the lower reflector or a part of the lower reflector while disposing the discharge lamp movably around a support shaft provided at the lower part of the lower reflector, the discharge lamp with all or part of the reflector freely pivoted in the front-rear and vertical directions to form a driving mechanism of a light source for switching the light distribution pattern into sub-beams and the main beam, at the time of sub-beam irradiation, the focus F1 of the upper reflector together are a focal point F2 of the lower reflector offset in the longitudinal direction to sandwich the light source on the same optical axis L, also at the time of main-beam irradiated, thereby the light source is slightly below f movement of the optical axis, the focal point F1 of the upper reflector is brought closer to the vicinity of, the irradiation before the vehicle portion of the optical axis of the lower reflector or the lower reflector is characterized by being configured to face upwardly .

Images