Illumination – Supported by vehicle structure – Condition responsive
Reexamination Certificate
2002-08-07
2004-04-20
O'Shea, Sandra (Department: 2875)
Illumination
Supported by vehicle structure
Condition responsive
C362S466000, C362S247000, C362S276000, C362S543000, C362S212000, C362S215000, C315S082000, C307S010800, C701S049000, C340S468000, C340S469000
Reexamination Certificate
active
06722775
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a headlamp device for a vehicle that has an auxiliary lamp unit for reinforcing the brightness of the side end portion of a headlamp light distribution pattern.
2. Prior Art
In general, the headlamp for a vehicle is capable of selectively switching between a low beam light distribution pattern and a high beam light distribution pattern. However, in vehicle headlamps in which the structures of these respective light distribution patterns is fixed, it is difficult to execute a beam irradiation in accordance with a proper light distribution pattern in response to the condition of a running vehicle.
Accordingly, a vehicle headlamp device that overcomes such problems was demanded, and a headlamp device that uses an auxiliary lamp unit has been proposed. The auxiliary lamp unit executes a beam irradiation in accordance with its auxiliary light distribution pattern so as to reinforce the brightness of the side end portion of the headlamp light distribution pattern formed by the beam irradiation of the headlamp unit. The auxiliary lamp unit is turned on and off in response to the vehicle running condition.
FIG. 6
shows, in a perspective manner, a light distribution pattern formed by the headlamp device described above, assuming that the vehicle is turning left.
As seen from
FIG. 6
, in this headlamp device, a low beam irradiation is executed by the headlamp unit in accordance with its headlamp light distribution pattern P(L)′ that has a horizontal cut-off line CL
1
′ and an oblique cut-off line CL
2
′, and a beam irradiation is executed by the auxiliary lamp unit in accordance with its auxiliary light distribution pattern Pa′ so as to reinforce the brightness of the left end portion of the headlamp light distribution pattern P(L)′. With this headlamp device, the road surface in front of the vehicle at the time of turning left is broadly irradiated by way of simultaneously turning on the headlamp unit and the auxiliary lamp unit.
However, in the vehicle headlamp device described above, a high luminous intensity area (hot zone) HZ
1
′ of the auxiliary light distribution pattern Pa′ is formed at a position considerably apart from a high luminous intensity area HZ(L)′ of the headlamp light distribution pattern P(L)′. Accordingly, the problem is that the portion between the high luminous intensity areas HZ(L)′ and HZ
1
′ on the road surface in front of the vehicle becomes relatively dark due to the contrast between the high luminous intensity areas HZ(L)′ and HZ
1
′. As a result, the visibility in that portion is low.
In particular, the clipping point CP on a left curve road (a point to which it is considered that the driver pay his/her attention when turning left, that is, a position of the contact point when an eye point of the driver and the road shoulder side lane mark LM are connected with a tangent line) in front of the vehicle shifts toward the high luminous intensity area HZ(L)′ of the headlamp light distribution pattern P(L)′ as shown by arrows in
FIG. 6
in accordance with the increase of the vehicle speed. Thus, the problem is that the high luminous intensity area HZ
1
′ of the auxiliary light distribution pattern Pa′ formed on the
0
left front side significantly reduces the visibility of the clipping point CP at the time of turning left at a high speed.
SUMMARY OF THE INVENTION
The present invention is made in light of the problems with the conventional vehicle headlamps described above.
It is an object of the present invention to provide an improvement in a headlamp device for a vehicle that is provided with an auxiliary lamp unit which executes a beam irradiation in accordance with its auxiliary light distribution pattern so as to reinforce the brightness of the side end portion of a headlamp light distribution pattern; and in the present invention, the vehicle headlamp device sufficiently increases the visibility of the road surface in front of the vehicle at the time of turning of the vehicle.
In other words, the present invention accomplishes the above object by applying innovation to the luminous intensity distribution in an auxiliary light distribution pattern and by providing a structure capable of controlling the light.
More specifically, the above object is accomplished by a unique structure for a headlamp device for a vehicle that includes:
a headlamp unit which irradiates a beam toward a front side of a vehicle in accordance with a predetermined headlamp light distribution pattern thereof, and
an auxiliary lamp unit which irradiates a beam in accordance with an auxiliary light distribution pattern thereof so as to reinforce the brightness of a side end portion of the headlamp light distribution pattern; and in the present invention:
the high luminous intensity area of the auxiliary light distribution pattern is formed at a position closer to the high luminous intensity area of the headlamp light distribution pattern than to the center position of the auxiliary light distribution pattern, and
a light control means that varies the beam irradiation intensity of the auxiliary lamp unit is connected to the auxiliary lamp unit.
The specific structures of the “headlamp unit” and the “auxiliary lamp unit” are not particularly limited; and, for instance, a so-called parabola type lamp device unit and a so-called projector type lamp device unit can be employed therefor. In addition, the structures of the light sources for the “headlamp unit” and the “auxiliary lamp unit” are not particularly limited; and, for instance, a discharge light-emitting portion of a discharge bulb and a filament of an incandescent bulb such as a halogen bulb can be employed as the light sources of the headlamp unit and the auxiliary lamp unit.
Furthermore, the “auxiliary lamp unit” can be a lamp that reinforces the brightness of either the right or left end portions of the headlamp light distribution pattern by the auxiliary light distribution pattern formed by the beam irradiation from the auxiliary lamp unit.
The “headlamp light distribution pattern” refers to a light distribution pattern that carries out a function of a headlamp, and it includes a high beam light distribution pattern and a low beam light distribution pattern.
The “light control means” is not particularly limited in its specific contents of variable control as long as it can vary the beam irradiation intensity of the auxiliary lamp unit.
As seen from the above, the headlamp device for a vehicle according to the present invention includes a headlamp unit, which irradiates the beam toward the front of the vehicle in accordance with its headlamp light distribution pattern, and a auxiliary lamp unit, which irradiates the beam in accordance with its auxiliary light distribution pattern so as to reinforce the brightness of the side end portion of the headlamp light distribution pattern; and in the present invention, the high luminous intensity area of the auxiliary light distribution pattern is formed at the position closer to the high luminous intensity area of the headlamp light distribution pattern than to the center position of the auxiliary light distribution pattern. Accordingly, the headlamp light distribution pattern and the auxiliary light distribution pattern are smoothly combined together, while the brightness of the side end portion of the headlamp light distribution pattern is reinforced by the auxiliary light distribution pattern of the auxiliary lamp unit.
Further, in the present invention, the light control means that varies the beam irradiation intensity of the auxiliary lamp unit is connected to the auxiliary lamp unit. Accordingly, the auxiliary light distribution pattern can be formed in response to the vehicle running condition. When the beam irradiation intensity of the auxiliary lamp unit is gradually increased by the light control means, the high luminous intensity area becomes bright at first, then the periphery gradually
Cranson, Jr. James W
Koda & Androlia
Koito Manufacturing Co. Ltd.
O'Shea Sandra
LandOfFree
Headlamp device for vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Headlamp device for vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Headlamp device for vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3268414