Patent Description:
General vehicles each have a headlight or headlights called headlamp at a front portion or portions thereof. In recent years, a structure has come to be proposed in which a light guide member is additionally provided and a headlight is made to shine partially (see, for example, <CIT> (<FIG> and <FIG>)).

As shown in <FIG> of <CIT>, four second light sources (<NUM>) (parenthesized numerals appearing here and hereafter are reference symbols used in <CIT>) are provided on a base member (<NUM>). Semicircular arched light guide members (130a, 130b) are attached to the base member (<NUM>). Since one end and the other end of the light guide member (130a) abut on the second light sources (<NUM>), the light guide member (130a) shines as a whole. The same applies to the light guide member (130b).

As illustrated in <FIG> of <CIT>, the shining light guide members (130a, 130b) are visible through a lens (<NUM>). The light emitted from the second light sources (<NUM>) and entering the semicircular arched light guide member (130a) via both ends of the light guide member (130a) travels on through the light guide member (130a), to reach an uppermost position of the light guide member (130a). The light entering the semicircular arched light guide member (130b) via both ends of the light guide member (130b) travels on through the light guide member (130b), to reach a lowermost position of the light guide member (130b).

Light is known to be lowered in brightness, due to diffusion or consumption, as it travels on. It is supposed, therefore, that the second light sources (<NUM>) appear brighter than other parts. In <CIT>, the light guide portion (<NUM>) is divided into two parts, as a contrivance to suppress color shading.

Where the headlight is enlarged in size or in diameter, the number of parts into which the headlight is divided may be increased, whereby color shading can be suppressed. It is to be noted in this case, however, that the number of the second light sources (<NUM>) is increased.

Thus, in the structure according to <CIT>, structural designing of the light guide member (<NUM>) is difficult to carry out, and the degree of freedom of shape is lowered.

<CIT> discloses a headlamp structure for vehicles, specifically for enhancing visibility and attention while incorporating features such as a main light source and auxiliary light-emitting components. The structure consists of a housing forming the body of the head-lamp, accommodating a first light source designed to emit main headlamp rays. The front of the housing is covered by a bezel, featuring a transparent lens for diffusing and converging the emitted light, A reflector positioned within the housing redirects the light forward. Further, the structure integrates an auxiliary light-emitting body that enhances visibility and simplifies the vehicle's design. This auxiliary light comprises a light guide member encircling the reflector. A second light source is strategically positioned to remain concealed behind the bezel when viewed from the front, illuminating the light guide member via total internal reflection. Additionally, a control unit is provided to manage the operation of the main and auxiliary light sources, allowing synchronized control for improved functionality.

<CIT> disloses a further headlight structure for a two-wheeled motor vehicle with a light guide positioned in a recessed part of a front upper cowl along an outer periphery of the headlight on a vehicle body center line.

On the other hand, headlights are being diversified in shape. Accordingly, there is a need for a headlight structure which ensures easy structural designing of a light guide portion (light guide member) and makes it possible to enhance the degree of freedom of shape.

It is an object of the present invention to provide a headlight structure which ensures easy structural designing of a light guide member and makes it possible to enhance the degree of freedom of shape.

According to the invention as recited in claim <NUM>, there is provided a headlight structure for a vehicle, including: two first light sources which are accomodated in a housing and emit headlight rays; a light-blocking light cover which covers a front surface of the housing; two reflectors which are disposed between the light cover and the housing, and reflect forward the rays emitted by the first light sources; and two lenses which is provided on the light cover and permit transmission of the rays therethrough while converging the rays. The headlight structure for a vehicle further includes: a light guide member which is mounted to the housing so as to fringe the periphery of the reflector, permits light to travel on therethrough and shines; the vehicle is a saddle type vehicle and the headlight structure further comprises two second light sources which are disposed in such a part as to be hidden behind the light cover when viewed from the vehicle front side, and emit light guide member rays toward the light guide member; and a control unit which controls turned-on states of the first light sources and the second light sources. Two second light sources are disposed on each of the left and right sides of the light guide member.

Each reflector is a lower half concave mirror obtained by removing an upper half from a concave mirror; each first light source is a light emitting diode which emits rays downward; and the second light sources are disposed above the reflector.

The vehicle is a saddle type vehicle; the first light sources, the the reflectors and the lenses are disposed on each of left and right sides of a vehicle body center line of the vehicle; the light guide member is roughly W-shaped when viewed from the vehicle front side and including two , left and right, shining portions shaped to increase width a s the distance from the respective second light sources increases; and the second light sources are attached to each of left and right sides of the light guide member.

According to the invention as recited in claim <NUM>, the headlight structure for a vehicle is characterized in that: of the left and right reflectors, one is a high-beam reflector for exclusive use for high beam, and the other is a high/low-beam reflector for combined use for high and low beams; the control unit, when a high beam mode is selected, performs a control such as to turn on the left and right first light sources and to turn on the second light sources; and the control unit, when a low beam mode is selected, performs a control such as to turn on the first light source on the side of the high/low-beam reflector, turn on the second light sources, and turn off the first light source on the side of the high-beam reflector.

According to the invention as recited in claim <NUM>, the headlight structure for a vehicle is characterized in that the shining portion permits shining with introduced light; and the light guide member further includes two connection portions which interconnect the second light sources and the shining portions, the connection portions being circular in section.

According to the invention, the second light sources are covered by the light cover. Even when the second light sources are brighter than other portions, therefore, they are invisible externally. As a result, unevenness in brightness within an externally visible region can be suppressed. Since the unevenness in brightness can be reduced, the headlight can be easily made larger in size or in diameter.

Since it is easy to determine the position of the second light sources, structural designing of the light guide member is easy to carry out, and the degree of freedom of shape can be enhanced.

According to the invention, each reflector is a lower half concave mirror. Therefore, a space on the upper side of the reflectors can be utilized, and the second light sources can be disposed in the upper-side space. Besides, the first light sources are light emitting diodes which emit rays downward, and, accordingly, the first light sources can also be disposed in the upper-side space. The second light sources can be disposed closer to the first light sources on a height basis, so that a power feeding system can be arranged in a more intensive form.

According to the invention, the light guide member is roughly W-shaped as viewed from the vehicle front side, and the second light sources are attached respectively to the left and right portions of the light guide member. When the light guide member is thus W-shaped, its left and right ends and its center (three portions in total) can be covered with the light cover. Thus, the second light sources, which are brighter than the other portions, and the central portion, which is darker than the other portions, are hidden by the light cover. As a result, unevenness in brightness can be suppressed more assuredly. Even where the headlight is elongated in the left-right direction, it is sufficient to arrange only two second light sources.

According to the invention as recited in claim <NUM>, the high-beam reflector and the high/low-beam reflector are arranged juxtaposedly in the left-right direction. In addition, the light guide member is made to shine both in the high beam mode and in the low beam mode. Consequently, it is possible to optimize the light distribution of the headlight on each of the left and right sides for the exclusive use (for high beam or for low beam), and it is possible, because of the presence of the light guide member, to enhance visibility in the low beam mode.

According to the invention as recited in claim <NUM>, the light guide member includes two shining portions which permit shining with introduced light, and two connection portions interconnecting the second light sources and the shining portions, the connection portions being circular in section. The circular cross section (particularly, true circular cross section) enables guiding of a larger quantity of light than a rectangular or polygonal cross section, thereby enabling the shining portions to shine at a higher intensity.

Although the connection portions are brighter than the other portions, they are covered with the light cover and, hence, unevenness in brightness of the light guide member can be restrained.

An illustrative embodiment of the present invention will be described below, referring to the attached drawings. Note that the drawings should be looked at in accordance with the orientation of reference symbols.

As shown in <FIG>, a saddle type vehicle <NUM>, which is a vehicle to be ridden by a driver seated astride a seat <NUM>, includes: a front fork <NUM> steerably mounted to a front portion of a body frame <NUM>; a front wheel <NUM> rotatably mounted on lower portions of the front fork <NUM>; a steering handlebar <NUM> attached to an upper portion of the front fork <NUM>; a fuel tank <NUM> and the seat <NUM> disposed sequentially on the rear side of the steering handlebar <NUM> and supported by the body frame <NUM>; an engine <NUM> disposed under the fuel tank <NUM> and supported by the body frame <NUM>; a swing arm <NUM> extending rearward from the body frame <NUM>; a rear wheel <NUM> rotatably mounted on the swing arm <NUM>; a front cowl <NUM> disposed forwardly of the fuel tank <NUM> so as to surround the front fork <NUM>; a windscreen <NUM> mounted to an upper portion of the front cowl <NUM>; and a headlight <NUM> mounted to a front portion of the front cowl <NUM>.

As depicted in <FIG>, the windscreen <NUM> is disposed over the front cowl <NUM>. The windscreen <NUM> is supported by a windscreen stay <NUM>. The windscreen <NUM> is a vertically elongated windscreen which is greater in vertical size than in the size in a vehicle width direction. An opening <NUM> penetrating the windscreen <NUM> in a longitudinal vehicle direction (in a face-back direction of the sheet of the drawing) is provided below the center in a height direction of the vertically elongated windscreen <NUM>. Furthermore, the windscreen <NUM> has left and right cutouts <NUM> and 28R (L is a suffix representing the left, and R the right, here and hereafter) on the left and right sides of the opening <NUM> so that its lower portion below the center in the height direction thereof is necked.

The front cowl <NUM> is provided with the headlight <NUM> in the center in the vehicle width direction, airflow inlets <NUM> and 29R on the left and right sides of the headlight <NUM>, and left and right turn signal lamps <NUM> and 31R at upper portions.

When viewed from the vehicle front side, the turn signal lamps <NUM> and 31R overlap with grip guards <NUM> and 32R on the depth side (rearward side) thereof.

As shown in <FIG>, the headlight <NUM> includes, as main elements: a housing <NUM>; an adjustment plate <NUM> locked to pivots <NUM> provided on the housing <NUM>; a high/low-beam reflector <NUM> and a high-beam reflector <NUM> provided on the adjustment plate <NUM>; a light guide member <NUM> having a roughly W-shaped form and mounted to the adjustment plate <NUM> along edges of the reflectors <NUM> and <NUM>; a light-blocking light cover <NUM> to be put on the housing <NUM>; and light-transmitting lenses <NUM> and 49R formed in the light cover <NUM>.

The high/low-beam reflector <NUM> and the high-beam reflector <NUM> are each a lower-half concave mirror obtained by removing an upper half from a concave mirror.

As illustrated in <FIG>, the light guide member <NUM> includes: attachment portions <NUM>; connection portions <NUM> (one of which is not shown) extending from the attachment portions <NUM>; semicircular arched shining portions <NUM> extending from tips of the connection portions <NUM>; and an intermediate portion <NUM> interconnecting the left and right shining portions <NUM>.

In the vicinities of the attachment portions <NUM>, second light sources <NUM> are attached to the connection portions <NUM>. The second light sources <NUM> are light emitting diodes.

The connection portion <NUM> is circular in section. The sectional shape is desirably a true circle, but may be an ellipse or an oblong.

Fresnel cutting is applied to the shining portions <NUM>. Specifically, the shining portions <NUM> are cut into the shape of minute sawteeth, and the sawtooth surface serves as diffuse reflection surfaces, so that these portions shine remarkably as compared with other portions. Besides, the shining portions <NUM> are shaped to increase in width as the distance from the second light source <NUM> increases so that the width b at a central portion of the light guide member <NUM> is greater than the width a at both ends thereof (a < b), as shown in <FIG>.

As depicted in <FIG>, the attachment portions <NUM>, the connection portions <NUM>, and the intermediate portion (reference symbol <NUM> in <FIG>) are hidden by the light cover <NUM>. On the other hand, the left and right reflectors <NUM> and <NUM> and the left and right shining portions <NUM> are visible through the lenses <NUM> and 49R.

In other words, the left and right reflectors <NUM> and <NUM> and the left and right lenses <NUM> and 49R are disposed on the left and right sides of a vehicle body center line <NUM>. Besides, the second light sources <NUM> are disposed respectively at the left and right ends of the light guide member <NUM>, which has a roughly W-shaped form.

As shown in <FIG>, the second light source <NUM> is a light emitting diode, and is integrally formed on a substrate <NUM>. The substrate <NUM> is put on the housing <NUM>, and the attachment portion <NUM> is laid on the substrate <NUM> so that the second light source <NUM> and the connection portion <NUM> overlap with each other. Then, the attachment portion <NUM> and the substrate <NUM> are co-fastened to the housing <NUM> by a screw <NUM>.

As depicted in <FIG>, a pivot bolt <NUM> is screwed into an upper portion of the housing <NUM> from the light cover <NUM> side. A bolt head of the pivot bolt <NUM> is the spherical pivot <NUM>, to which the adjustment plate <NUM> is swingably attached.

As shown in <FIG>, an optical axis adjustment screw <NUM> is attached to a lower portion of the housing <NUM>. The optical axis adjustment screw <NUM> is rotated by turning an adjustment knob <NUM>. The optical axis adjustment screw <NUM> is in screw engagement with a lower portion of the adjustment plate <NUM>. With the optical axis adjustment screw <NUM> turned, the lower portion of the adjustment plate <NUM> is made to advance or retract. As a result, the adjustment plate <NUM> is oscillated about the pivot (reference symbol <NUM> in <FIG>), whereby an optical axis adjustment (aiming) can be achieved.

As illustrated in <FIG>, the adjustment knob <NUM> is disposed at a lower portion in the center in the vehicle width direction of the housing <NUM>. A harness <NUM> laid in the vicinity of the adjustment knob <NUM> is positioned by a harness retainer <NUM> in such a position as not to hamper turning of the adjustment knob <NUM>.

As shown in <FIG>, a first light source <NUM> is attached to the housing <NUM> at a position over the reflector <NUM>. The first light source <NUM> is a light emitting diode which emits light downward. The light is reflected by the reflector <NUM> to pass through the lens 49R and travel toward the forward side of the vehicle.

Since there is a vacant space on the upper side of the reflector <NUM>, the first light source <NUM> is disposed there. Besides, since there is the vacant space on the upper side of the reflector <NUM>, the second light source <NUM> is disposed there. Thus, the plurality of light sources <NUM> and <NUM> are disposed at substantially the same height, so that a power feeding system can be laid easily.

As illustrated in <FIG>, turning-on and turning-off of the left and right first light sources <NUM> and the left and right second light sources <NUM> are controlled by a control unit <NUM>.

Specifically, in a high beam mode, as depicted in <FIG>, the left and right first light sources <NUM> are turned on and the second light sources <NUM> are turned on. As a result, the left and right reflectors <NUM> and <NUM> shine, and the light guide member <NUM> shines.

When a low beam mode is selected, as shown in <FIG>, the first light source <NUM> on the high/low-beam reflector <NUM> side is turned on and the second light sources <NUM> are turned on, but the first light source <NUM> on the high-beam reflector <NUM> side is turned off. As a result, the left reflector <NUM> shines, and the light guide member <NUM> shines.

The operation of the control unit <NUM> as aforementioned is merely a preferable example, and the form of turning-on/turning-off may be modified, as required.

While the saddle type vehicle on which the headlight of the present invention is mounted has been a motorcycle in the aforementioned embodiment, the saddle type vehicle may be a three-wheeled vehicle or four-wheeled vehicle.

The headlight according to the present invention is suitable for a saddle type vehicle having two wheels.

Claim 1:
A headlight structure for a vehicle, comprising:
two first light sources (<NUM>) accommodated in a housing (<NUM>), the first light sources (<NUM>) adapted to emit headlight rays;
a light-blocking light cover (<NUM>) covering a front surface of the housing (<NUM>); two reflectors (<NUM>, <NUM>) disposed between the light cover (<NUM>) and the housing (<NUM>), the reflectors (<NUM>, <NUM>) reflecting forward the rays emitted by the first light sources (<NUM>); and
two lenses (<NUM>, 49R), provided on the light cover (<NUM>), the lenses (<NUM>, 49R) permitting transmission of the rays therethrough while converging the rays; and
a light guide member (<NUM>) mounted to the housing (<NUM>) so as to fringe a periphery of the reflectors (<NUM>, <NUM>), the light guide member (<NUM>) adapted to permit light to travel on therethrough and adapted to shine; wherein the vehicle is a saddle type vehicle (<NUM>), and wherein the headlight structure further comprises:
two second light sources (<NUM>) disposed in such a part as to be hidden behind the light cover (<NUM>) when viewed from a vehicle front side, the second light sources (<NUM>) adapted to emit light guide member rays toward the light guide member (<NUM>); and
a control unit (<NUM>) adapted to control turned-on states of the first light sources (<NUM>) and the second light sources (<NUM>),
the second light sources (<NUM>) being disposed on each of the left and right sides of the light guide member (<NUM>), and
each reflector (<NUM>, <NUM>) is a lower half concave mirror obtained by removing an upper half from a concave mirror,
each first light source (<NUM>) is a light emitting diode which emits rays downward, and
the second light sources (<NUM>) are disposed above the reflectors (<NUM>, <NUM>), and
the first light sources (<NUM>), the reflectors (<NUM>, <NUM>) and the lenses (<NUM>, 49R) each are disposed on a respective left and right side of a vehicle body center line (<NUM>) of the vehicle, and
the light guide member (<NUM>) being roughly W-shaped when viewed from the vehicle front side and including two, left and right, shining portions (<NUM>) shaped to increase width as the distance from the respective second light sources (<NUM>) increases.