Patent Description:
Conventionally, a vehicular front lamp is known that includes a semiconductor light-emitting element used as a light source, and a projection lens that projects light emitted from the semiconductor light-emitting element and irradiates the projected light toward the outside from an irradiation surface. The projection lens is such that at least a center part of the irradiation surface is formed as a first control portion and at least a portion of at least an outer peripheral portion of the irradiation surface is formed as a second control portion. Light emitted from a light emitting point on an optical axis that passes through the focal point of the projection lens is radiated from the first control portion as parallel light that is parallel to the optical axis, and is radiated from the second control portion to the outside with respect to a line segment that is parallel to the optical axis. At least the first control portion of the projection lens is formed as a diffusion portion that diffuses light (see Patent Literature <NUM>).

Patent Literature <NUM> discloses that the blue component of the light emitted from the semiconductor light-emitting element will not easily reach the outer peripheral portion of the light distribution pattern, and thus chromatic aberration will not easily occur, and light radiated from the diffusion portion diffuses and tends to mix with the blue component. As a result, the generation of the color blue in the light distribution pattern is suppressed, so a good light distribution pattern is able to be formed.

When looking at <FIG> of Patent Literature <NUM>, the projection lens will emit light and be visible when illuminated, but a considerably large projection lens is used for a light emitter formed by a base portion and a semiconductor light-emitting element arranged on the base portion. Therefore, in Patent Literature <NUM>, the light-emitting part as the vehicular lamp is considered to be comparatively large.

In recent years, with a reduction in size of vehicular lamps, there have come to be cases in which vehicular lamps having a slim appearance with smaller light-emitting parts are needed.

The present invention has been made in view of the problem described above, and it is an object of the present invention to provide a vehicular lamp that can be made small and has a small light-emitting part.

In order to achieve the above object, the present invention is realized by a vehicular lamp according to the appended claims.

According to the present invention, a vehicular lamp that can be made small and has a small light-emitting part can be provided.

Hereinafter, modes for carrying out the present invention (hereinafter, simply referred to as "embodiments") will be described in detail with reference to the accompanying drawings. Like elements throughout the entire description of the embodiments will be denoted by like numerals. Also, unless otherwise noted, in the embodiments and drawings, "front" and "rear" indicate the "forward direction" and "reverse direction," respectively, of a vehicle, and "upper," "lower," left," and "right" all indicate directions from the viewpoint of a driver riding in the vehicle.

A vehicular lamp according to an embodiment of the present invention is a vehicular front lamp (101R, <NUM>) provided on the left and right sides, respectively, at the front of a vehicle <NUM> illustrated in <FIG>, but will hereinafter simply be referred to as a vehicular lamp.

The vehicular lamp of the present embodiment includes a housing (not shown) that is open to the vehicle front side, and an outer lens (not shown) that attaches to the housing so as to cover the opening. A lamp unit <NUM> (see <FIG>) and the like is arranged inside a lamp chamber formed by the housing and the outer lens.

<FIG> is a front view of the lamp unit <NUM> for the left side of a vehicle.

As illustrated in <FIG>, the lamp unit <NUM> is a variable light distribution type high beam light distribution unit in which a plurality of light-emitting chips <NUM> are arranged lined up side by side, and that is capable of performing so-called ADB (Adaptive Driving Beam) control that turns some or all of the light-emitting chips <NUM> on/off in accordance with the positional relationship with a leading vehicle and the like.

Note that a lamp unit for the right side of the vehicle is just symmetrical with the lamp unit <NUM> for the left side of the vehicle, so hereinafter, mainly the lamp unit <NUM> for the left side of the vehicle will be described as an example.

<FIG> is an exploded perspective view of the lamp unit <NUM>.

As illustrated in <FIG>, the lamp unit <NUM> includes a heat sink <NUM>, a light source <NUM>, a reflecting board <NUM>, a lens holder <NUM>, a lens <NUM>, and a cooling fan <NUM>.

The heat sink <NUM> has a base portion <NUM>, heat dissipating fins <NUM>, and cooling fan mounting portions <NUM>.

A front surface 21a of the base portion <NUM> forms a light source arranging portion for arranging the light source <NUM>. On a rear surface 21b positioned on the opposite side from the front surface 21a of the base portion <NUM>, a plurality of the heat dissipating fins <NUM> are formed lined up in the horizontal direction and extending rearward from the rear surface 21b.

On left and right outsides in the horizontal direction of the rear surface 21b of the base portion <NUM>, the cooling fan mounting portions <NUM> for mounting the cooling fan <NUM> are formed extending rearward from the rear surface 21b, similar to the heat dissipating fins <NUM>.

In generally the vertical center in the vertical direction of the front surface 21a of the base portion <NUM> is formed a pair of left and right bosses 24a for positioning the light source <NUM> and the reflecting board <NUM> when mounting the light source <NUM> and the reflecting board <NUM>, and a pair of left and right screw fixing holes 24b, for screwing screws <NUM> to mount and fix the light source <NUM> and the reflecting board <NUM> into, are formed in positions slightly above the pair of left and right bosses 24a.

Also, the base portion <NUM> has shaped portions in which a portion protrudes toward the outside, formed in positions on the left and right outsides in generally the vertical center in the vertical direction. On these protruding portions is formed a pair of left and right bosses 25a for positioning the lens holder <NUM> when mounting the lens holder <NUM> to the heat sink <NUM>, and a pair of left and right screw fixing holes 25b, for screwing screws <NUM> to mount and fix the lens holder <NUM> into, are formed in positions slightly above the pair of left and right bosses 25a.

Furthermore, one screw fixing hole 25b, for screwing the screw <NUM> to mount and fix the lens holder <NUM> into, is also provided on the lower side, in generally the lateral center in the horizontal direction, of the base portion <NUM>.

Meanwhile, screw fixing holes (not shown), for screwing screws <NUM> to mount the cooling fan <NUM> into, are also provided in the cooling fan mounting portions <NUM>.

The cooling fan <NUM> has an impeller <NUM> that rotates in response to electricity being supplied, and is arranged behind the heat dissipating fins <NUM> so as to send wind generated by the impeller <NUM> to the heat dissipating fins <NUM>.

More specifically, in the cooling fan <NUM>, screw holes <NUM> through which the screws <NUM> pass are formed in a casing <NUM> that covers the outer periphery of the impeller <NUM>. The cooling fan <NUM> is mounted in a position behind the heat dissipating fins <NUM>, by passing the screws <NUM> through these screw holes <NUM> from behind and screwing the screws <NUM> into screw fixing holes (not shown) provided in the cooling fan mounting portions <NUM> of the heat sink <NUM>.

Note that although it is not absolutely necessary to provide the cooling fan <NUM>, in a case where a plurality of light-emitting chips <NUM> are provided, as in the present embodiment, the amount of heat that is generated increases with the increase in the number of light-emitting chips <NUM>, so it is preferable to provide the cooling fan <NUM> to efficiently cool the light-emitting chips <NUM>.

The light source <NUM> is a semiconductor light source in which a plurality of (<NUM>) light-emitting chips <NUM> (LED chips) are arranged side by side on a circuit board <NUM>. An electric connector <NUM> for supplying electricity and the like to the light-emitting chips <NUM> (LED chips) is provided on the circuit board <NUM>.

Also, boss holes 34a through which the bosses 24a provided on the base portion <NUM> of the heat sink <NUM> pass and screw holes 34b through which the screws <NUM> pass are formed to the left and right outsides of the position where the light-emitting chips <NUM> are provided on the circuit board <NUM>.

In the present embodiment, five light-emitting chips <NUM> are provided on the vehicle outside and six light-emitting chips <NUM> are provided on the vehicle inside, with the optical axis center O of the lamp unit <NUM> sandwiched therebetween, as illustrated in <FIG>.

The lamp unit <NUM> of the present embodiment takes the lamp unit <NUM> provided in a vehicular lamp for the left side of a vehicle as an example, as described above, and forms a light distribution pattern corresponding to the left half of a high beam light distribution pattern. Note that the vehicular lamp according to the present invention includes a left side lamp unit <NUM> that forms a light distribution pattern upward on the left side of the vehicle, and a right side lamp unit <NUM> that forms a light distribution pattern upward on the right side of the vehicle.

Therefore, the left side of <FIG> is the vehicle inside, and the right side of <FIG> is the vehicle outside. In the present embodiment, the number of light-emitting chips <NUM> arranged sandwiching the optical axis center O is greater by one on the vehicle inside.

Here, the image of the light from the light-emitting chips <NUM> on the vehicle inside is radiated toward the vehicle outside through the lens <NUM>.

Therefore, the high beam light distribution pattern is able to be wider on the vehicle outside, such that the visibility range on the vehicle outside is able to be wider, by arranging more of the light-emitting chips <NUM> on the vehicle inside, as in the present embodiment.

Note that in the lamp unit for the right side of the vehicle as well, the visibility range on the vehicle outside can be made wider by increasing the number of light-emitting chips on the vehicle inside.

In the present embodiment, a case in illustrated in which the number of light-emitting chips <NUM> arranged on the vehicle inside is one more than the number of light-emitting chips <NUM> arranged on the vehicle outside with the optical axis center O sandwiched therebetween, but the number of light-emitting chips <NUM> arranged on the vehicle inside may be even more than one more than the number of light-emitting chips <NUM> arranged on the vehicle inside with the optical axis center O sandwiched therebetween.

Further, it goes without saying that the number of light-emitting chips <NUM> provided on the circuit board <NUM> is not particularly limited unless ADB control and the like is taken into consideration. However, if there are five or more, the circuit board <NUM> and the like tends to become large, so achieving slimness may be said to be of great significance. Thus, it may be said that the case of the light source <NUM> having five or more light-emitting chips <NUM> is preferable.

Note that in the present embodiment, a case with the semiconductor light source <NUM> in which the light-emitting chips <NUM> are LED chips is described, but the present invention is not limited to this. For example, a semiconductor light source in which the light-emitting chips <NUM> are semiconductor laser chips or EL (organic EL) chips may also be used.

Incidentally, as described above, when a plurality of light-emitting chips <NUM> are used, the amount of heat generated increases by a corresponding amount, so it is preferable that efficient cooling be able to be performed.

Therefore, in the present embodiment, a heat dissipation circuit board in which power supply wiring and the like is printed, so that it will not short circuit, on a copper plate is used for the circuit board <NUM>.

By doing so, the heat generated when the light-emitting chips <NUM> emit light is able to be quickly transmitted to the heat sink <NUM> via the circuit board <NUM> that has low thermal resistance, thus making it possible to increase cooling efficiency.

Note that the circuit board <NUM> is not limited to being made using a copper plate, and may also be, for example, a heat dissipation circuit board having an aluminum plate base, or a heat dissipation circuit board in which an epoxy layer and a metal material layer are laminated in multiple layers.

As illustrated in <FIG>, the reflecting board <NUM> has a bottom portion <NUM>, and a pair of left and right mounting arm portions <NUM> that are provided on the left and right outsides in the horizontal direction of the bottom portion <NUM> and extend upward in the vertical direction from the bottom portion <NUM>.

Also, boss holes 44a through which the bosses 24a provided on the base portion <NUM> of the heat sink <NUM> pass, and screw holes 44b through which the screws <NUM> pass, are formed in these mounting arm portions <NUM>. Therefore, the light source <NUM> and the reflecting board <NUM> can be mounted to the heat sink <NUM> by the following process.

First, the bosses 24a of the base portion <NUM> are passed through the boss holes 34a in the circuit board <NUM> of the light source <NUM>, and the light source <NUM> is arranged on the front surface 21a of the base portion <NUM>. At this time, tip end sides of the bosses 24a protrude out from the boss holes 34a in the circuit board <NUM>.

Next, these protruding bosses 24a are passed through the boss holes 44a in the mounting arm portions <NUM> of the reflecting board <NUM>, and the reflecting board <NUM> is abuttingly arranged on the circuit board <NUM>. Then, the screws <NUM> are passed through the screw holes 44b in the mounting arm portions <NUM> of the reflecting board <NUM> and the screw holes 34b in the circuit board <NUM>, and screwed into the screw fixing holes 24b in the base portion <NUM>.

That is, the reflecting board <NUM> and the light source <NUM> are fixed to the base portion <NUM> in a co-locked state by the screws <NUM>.

As illustrated in <FIG>, a reflective surface <NUM> is formed on the bottom portion <NUM> of the reflecting board <NUM>.

More specifically, the reflective surface <NUM> is a surface that is inclined downward toward the front from an upper side 45a arranged near the lower end of the light-emitting chips <NUM>.

Then, when the light-emitting chips <NUM> are made to emit light, an image of light is reflected on this reflective surface <NUM>, and an image of light in which the light emitting surface and the reflected image appear connected is radiated forward through the lens <NUM>.

Therefore, the light distribution patterns formed by the light-emitting chips <NUM> are able to be expanded in the vertical direction compared to when the light distribution patterns are formed by only light from the actual light emitting surface.

However, while it is preferable to provide the reflecting board <NUM> from an optical viewpoint, there are cases where the reflecting board <NUM> is visibly recognizable through the lens <NUM>, so it is sometimes desirable not to provide the reflecting board <NUM> from the viewpoint of appearance.

Note that when it is desirable to form a light emission image similar to when using the reflecting board <NUM>, without using the reflecting board <NUM>, a row of the light-emitting chips <NUM> may be further provided on the lower side. In this way, the reflecting board <NUM> is not an essential structure, but an optional structure provided as necessary.

The lens <NUM> has a lens portion <NUM> and a flange portion <NUM> (mounting portion) provided on the outer periphery of the lens portion <NUM>. The lens portion <NUM> is a portion that light distribution controls the light from the light-emitting chips <NUM> and radiates the light forward so as to form a predetermined light distribution pattern. The lens <NUM> in the present embodiment has a rectangular shape when viewed from the front.

More specifically, the lens portion <NUM> is formed by a freeform surface in which an incident surface 61a into which light on the light-emitting chip <NUM> side enters and a light emission surface 61b from which the light is emitted are both formed protruding out. The incident surface 61a and the light emission surface 61b are formed so as to create a surface shape that performs a predetermined light distribution control.

Also, a polycarbonate resin or an acrylic resin can be suitably used for the lens <NUM>, but if heat from the light-emitting chips <NUM> is an issue, polycarbonate resin that has excellent heat resistance is better. However, if the lens <NUM> is desirable to suppress the generation of the blue spectral color in the light distribution pattern, then it is preferable to use an acrylic resin in which the wavelength dependence of the refractive index is small and spectroscopy is easily suppressed.

Also, as is evident from <FIG>, the width in the horizontal direction of the lens portion <NUM> is reduced to such an extent that it does not exceed twice the row width of the light-emitting chips <NUM> when viewed from the horizontal direction, and is reduced so that it is equal to or less than the lateral width in the horizontal direction of the circuit board <NUM>.

Therefore, when the light-emitting chips <NUM> are made to emit light, the lens portion <NUM> that emits light to become the light-emitting part is quite small, so a slim appearance can be realized.

Incidentally, although not illustrated, the lens portion <NUM> in the present embodiment is such that micro light diffusion structures of ridges that extend in the horizontal direction (more specifically, micro light diffusion structures having horizontally long semi-cylindrical shapes) are provided on the incident surface 61a in a continuous manner in the vertical direction.

As a result, light from each of the light-emitting chips <NUM> spreads out in the vertical direction when the light enters the lens portion <NUM> from the incident surface 61a, so the light distribution patterns are able to be blurred in the vertical direction.

Also, although not illustrated, the lens portion <NUM> in the present embodiment is such that micro light diffusion structures of ridges that extend in the vertical direction (more specifically, micro light diffusion structures having vertically long semi-cylindrical shapes) are provided on the light emission surface 61b in a continuous manner in the horizontal direction.

As a result, light spreads out in the left-right direction when emitted from the light emission surface 61b, so the light distribution patterns are able to be blurred in the left-right direction.

As described above, the lamp unit <NUM> of the present embodiment can be ADB controlled. Light from each of the light-emitting chips <NUM> is radiated forward in a manner such that light distribution patterns having a rectangular shape, for example, that are formed by the light from the light-emitting chips <NUM> partially overlap with adjacent light distribution patterns. Glare light with respect to a leading vehicle is able to be suppressed by turning some or all of the light-emitting chips <NUM> on/off in accordance with the positional relationship with the leading vehicle and the like.

However, when the light distribution patterns overlap in this way, streaks due to a difference in luminosity may appear at the boundary lines where the light distribution patterns overlap. However, streaks due to a difference in luminosity can be inhibited from appearing by blurring the distribution patterns, as described above.

Also, the micro light diffusion structures of ridges on the incident surface 61a and the light emission surface 61b are in a state similar to when mesh-like micro light diffusion structures are provided crossed when the lens portion <NUM> is viewed from the front.

Therefore, it is difficult to visually recognize the state of the inside through the lens <NUM>, so <FIG> shows straight through to the inside so that the state of the inside can be known. The light-emitting chips <NUM>, the reflecting board <NUM>, the screws <NUM> and the electric connector <NUM> can be made so as not to stand out, so there is also the effect that the appearance is able to be improved.

As illustrated in <FIG>, the lens holder <NUM> is formed by a first lens holder <NUM> arranged on the heat sink <NUM> side and a second lens holder <NUM> arranged on the front side of the first lens holder <NUM>.

The first lens holder <NUM> has an opening edge portion 51a that receives the flange portion <NUM> (mounting portion) of the lens <NUM> and an outer peripheral portion 51b that extends toward the heat sink <NUM> side from the opening edge portion 51a. A cutout portion 51c corresponding to a connecting portion 33a of the electric connector <NUM> is provided, so as to enable access to the connecting portion 33a of the electric connector <NUM> from the outside, on a portion on the upper side in the vertical direction of the outer peripheral portion 51b.

The inner opening shape of the opening edge portion 51a is substantially identical to the outer shape of the lens portion <NUM> of the lens <NUM>, and the outer shape of the opening edge portion 51a is substantially identical to the outer shape of the flange portion <NUM> (mounting portion) of the lens <NUM>.

In this way, the opening edge portion 51a is designed to be about the same size as the lens <NUM>, so as to not waste the design of the lens <NUM> that has been reduced in size.

Therefore, as can be understood from <FIG>, the opening width in the horizontal direction of the opening edge portion 51a is equal to or less than the lateral width in the horizontal direction of the circuit board <NUM>.

Meanwhile, if the outer peripheral portion 51b were formed in a straight shape from this opening edge portion 51a, the outer peripheral portion 51b would end up contacting the circuit board <NUM>, so the outer peripheral portion 51b has a shape that gradually widens toward the heat sink <NUM> side, so as to widen to approximately the same extent as the lateral width in the horizontal direction as the circuit board <NUM>, as illustrated in <FIG>.

Moreover, as illustrated in <FIG>, three leg portions 51d (see <FIG>) formed by standing leg portions 51da that extend toward the heat sink <NUM> side from the outer peripheral portion 51b following the widening of the outer peripheral portion 51b, and bent portions 51db that are bent so as to be substantially parallel to the front surface 21a of the base portion <NUM> from these standing leg portions 51da, are provided on the first lens holder <NUM>.

<FIG> is a top view of the lamp unit <NUM> viewed from above.

As illustrated in <FIG>, the standing leg portions 51da are formed extending from the outer peripheral portion 51b following the widening, so the heat sink <NUM> side of the standing leg portions 51da are positioned farther to the outside than the outer peripheral portion 51b side of the standing leg portions 51da. Furthermore, the bent portions 51db are arranged on the base portion <NUM> avoiding the circuit board <NUM>, by the bent portions 51db being formed while staying clear by a rounded shape to the outside.

Therefore, degradation of the leg portions 51d from the heat of the circuit board <NUM> can be avoided, and damage to the circuit board <NUM> during installation work can also be avoided.

Furthermore, the arrangement and the like of these three leg portions 51d will be described in detail with reference to <FIG>.

In <FIG>, the second lens holder <NUM> is positioned so as to cover the first lens holder <NUM>, so the first lens holder <NUM> itself is not visible. However, as is evident from <FIG>, the shape of the second lens holder <NUM> is basically the same as the shape of the first lens holder <NUM>, and the leg portions 51d of the first lens holder <NUM> are located directly behind leg portions 52d of the second lens holder <NUM>.

Also, the opening edge portion 51a of the first lens holder <NUM> is also positioned directly behind an opening edge portion 52a of the second lens holder <NUM>.

Therefore, it should be noted that the description below points out the leg portions 51d and the opening edge portion 51a of the first lens holder <NUM> that are positioned directly behind the leg portions 52d and the opening edge portion 52a of the second lens holder <NUM>.

As is evident from <FIG>, the arrangement of the three leg portions 51d is such that, in a front view, two leg portions 51d (one side leg portions) are in vertical positions in the vertical direction, and positioned slightly closer toward the electric connector <NUM> side than the light-emitting chips <NUM>, and farther to the left and right outsides in the horizontal direction than the electric connector <NUM>, and the remaining one leg portion 51d (other side leg portion) is positioned on a vertically lower side opposite the electric connector <NUM> with the light-emitting chips <NUM> sandwiched therebetween, and in substantially the center in the horizontal direction.

Note that in the present embodiment, the electric connector <NUM> is arranged vertically above the light-emitting chips <NUM>, but the electric connector <NUM> may also be arranged vertically below the light-emitting chips <NUM>. In this case as well, three leg portions 51d may on the whole be arranged in the state shown in <FIG> (that is, a state in which the upper and lower sides in <FIG> are reversed) based on the electric connector <NUM>.

That is, the arrangement of the three leg portions 51d need simply be such that, in the description above, the upper side is read as the lower side, and the lower side is read as the upper side.

Boss holes 55a through which the bosses 25a provided on the base portion <NUM> of the heat sink <NUM> pass and screw holes 55b through which the screws <NUM> pass are formed, as illustrated in <FIG>, in the bent portions 51db on the two leg portions 51d (one side leg portions) positioned to the left and right outsides in the horizontal direction of the electric connector <NUM>. Meanwhile, as is evident from <FIG>, only the screw hole 55b (not illustrated) through which the screw <NUM> passes is formed in the bent portion 51db of the leg portion 51d (other side leg portion) positioned on the vertically lower side opposite the electric connector <NUM> with the light-emitting chips <NUM> sandwiched therebetween.

In this way, by not having a boss for positioning pass through the bent portion 51db of the leg portion 51d (other side leg portion) positioned on the lower side, it is not necessary to perform the work of arranging the first lens holder <NUM> on the heat sink <NUM> so as to position the first lens holder <NUM> with respect to three bosses arranged in a triangle, so workability is able to be remarkably improved.

Also, with the arrangement of the leg portions 51d described with reference to <FIG>, the arrangement of the leg portions 51d can be one in which the leg portions 51d are positioned at the vertices of a triangle, so stable fixing to the heat sink <NUM> can be performed.

Incidentally, a further reduction in size is possible if the leg portions 51d (one side leg portions) positioned on the left and right outsides in the horizontal direction are not arranged protruding out on the left and right outsides.

Therefore, the diagonal lines of the opening edge portion 51a are shown as the Z axes in <FIG>, and if the bent portions 51db of the leg portions 51d (one side leg portions) positioned on the left and right outsides in the horizontal direction are placed in positions not overlapping with the electric connector <NUM>, in a range on the electric connector <NUM> side indicated by the arrows P from the diagonal lines, and these bent portions 51db are formed extending in a direction (for example, the vertical direction) that intersects with the horizontal direction, so as not to protrude out on the left and right sides, an even further reduction in size is possible, which is preferable.

Note that at this time, the positions of the leg portions 52d of the second lens holder <NUM> are of course also changed to match the change in the positions of the leg portions 51d (one side leg portions) of the first lens holder <NUM>.

Next, the second lens holder <NUM> will be described.

As illustrated in <FIG>, the second lens holder <NUM> has basically the same shape as the first lens holder <NUM>, and has the opening edge portion 52a of an opening shape substantially identical to the outer shape of the lens portion <NUM> of the lens <NUM>. The flange portion <NUM> (mounting portion) of the lens <NUM> is sandwiched from in front and behind by this opening edge portion 52a pushing the flange portion <NUM> (mounting portion) of the lens <NUM> toward the opening edge portion 51a side of the first lens holder <NUM>. As a result, the lens <NUM> is held by the lens holder <NUM>.

The second lens holder <NUM> also has an outer peripheral portion 52b that widens so as to follow the widening of the outer peripheral portion 51b of the first lens holder <NUM>, from the opening edge portion 52a toward the heat sink <NUM> side.

A cutout portion 52c corresponding to the electric connector <NUM> is also formed, similar to the first lens holder <NUM>, on a portion on the upper side in the vertical direction of this outer peripheral portion 52b.

Meanwhile, the second lens holder <NUM> is arranged overlapping over the first lens holder <NUM>. Therefore, as illustrated in <FIG>, the leg portions 52d are leg portions 52d that are formed by only bent portions formed following the bent portions 51db of the leg portions 51d of the first lens holder <NUM>, on the outside from substantially the peripheral edge portion on the heat sink <NUM> side of the outer peripheral portion 52b.

Also, as is evident from <FIG>, boss holes 54a through which the bosses 25a provided on the base portion <NUM> of the heat sink <NUM> pass and screw holes 54b (see <FIG>) through which the screws <NUM> pass, are formed in the two leg portions 52d positioned to the left and right outsides of the electric connector <NUM>. Meanwhile, only the screw hole 54b (not illustrated) through which the screw <NUM> passes is formed in the leg portion 52d positioned on the vertically lower side opposite the electric connector <NUM> with the light-emitting chips <NUM> sandwiched therebetween.

The second lens holder <NUM> is also formed having outer dimensions that are as small as possible so as to not waste the design of the lens <NUM> that has been reduced in size.

More specifically, the second lens holder <NUM> only has larger dimensions than the outer dimensions of the first lens holder <NUM> by approximately the thickness amount of the second lens holder <NUM>, such that the second lens holder <NUM> can be overlapped over the first lens holder <NUM>.

Also, the mounting of the lens <NUM> to the heat sink <NUM> by the lens holder <NUM> can be performed as described below with reference to <FIG>. First, the bosses 25a of the base portion <NUM> are passed through the boss holes 55a in the first lens holder <NUM>, and the first lens holder <NUM> is arranged on the base portion <NUM>. At this time, the tip end sides of the bosses 25a protrude out from the boss holes 55a in the first lens holder <NUM>.

Then, the lens <NUM> is inserted from the rear side of the outer peripheral portion 52b into the second lens holder <NUM> such that the flange portion <NUM> (mounting portion) of the lens <NUM> abuts against the opening edge portion 52a and the lens portion <NUM> of the lens <NUM> is in a state sticking out forward through the opening of the opening edge portion 52a. After this, the second lens holder <NUM> is placed over the first lens holder <NUM> such that the first lens holder <NUM> is housed inside the outer peripheral portion 52b of the second lens holder <NUM>, and the bosses 25a are inserted into the boss holes 54a in the second lens holder <NUM>.

Lastly, the screws <NUM> are passed through the screw holes 54b in the second lens holder and the screw holes 55b in the first lens holder from the second lens holder <NUM> side, and screwed into the screw fixing holes 25b in the base portion <NUM>. That is, the first lens holder <NUM> and the second lens holder <NUM> are fixed to the base portion <NUM> in a co-locked state by the screws <NUM>.

In this way, when assembly is finished, the lamp unit <NUM> illustrated in <FIG> and <FIG> is obtained. In the description above, the lens holder <NUM> is formed by two lens holders, i.e., the first lens holder <NUM> and the second lens holder <NUM>, but the second lens holder <NUM> is preferably omitted to further reduce the size.

In this case, the lens <NUM> is no longer able to be held by being sandwiched, so the lens <NUM> may be fixed to the first lens holder <NUM> by directly welding or adhering the flange portion <NUM> of the lens <NUM> to the opening edge portion 51a of the first lens holder <NUM>, for example.

Meanwhile, as is evident from <FIG>, the lateral width in the horizontal direction of the circuit board <NUM> can be further reduced by omitting the reflecting board <NUM>, but if this were done, the end in the horizontal direction of the circuit board <NUM> would be positioned inside the lens portion <NUM> when viewed from the front, and as a result, steps on the left and right sides of the circuit board <NUM> would be visible and the like, which would reduce the appearance.

Also, if the circuit board <NUM> were made smaller, it would lead to a reduction in the ability to radiate heat.

Therefore, even if the reflecting board <NUM> is omitted, it is desirable to have the lateral width in the horizontal direction of the circuit board <NUM> be larger than the lens portion <NUM>, the opening width of the opening edge portion 51a and the opening width of the opening edge portion 52a, as described above.

As described above, in the present embodiment, the lens <NUM> is reduced in size, and the lens holder <NUM> and the like is also reduced in size so as not to waste the design of this size reduction.

In particular, at the periphery of the lens <NUM>, the outer shape is no larger than about the thickness of the second lens holder <NUM> with respect to the size of the lens <NUM>. Therefore, the outer shape of the periphery of the lens <NUM> that is arranged in a position on the side that is visibly recognizable from a bezel and an inner panel is able to be kept extremely slim. Therefore, not only is the vehicular lamp simply able to be reduced in size, the vehicular lamp is also able to exhibit a slim light-emitting portion (lens portion) suitable for this reduction in size.

<FIG> is a front view of a lamp unit <NUM>' of a vehicular lamp according to a second embodiment of the present invention, viewed from the front.

The basic configuration of the second embodiment is similar to that of the first embodiment, so in the description below, mainly the points that differ will be described. Descriptions of portions similar to those of the first embodiment may be omitted.

First, as is evident from <FIG>, in the first embodiment, the circuit board <NUM> of the light source <NUM> is such that the lower end in the vertical direction is in a position substantially even with the lower end in the vertical direction of the reflecting board <NUM>.

On the other hand, in the second embodiment, the vertical width in the vertical direction of the circuit board <NUM> extends to the lower side. As illustrated in <FIG>, the vertical width in the vertical direction of the circuit board <NUM> is equal to or greater than the width in the vertical direction of the lens portion <NUM> of the lens <NUM>, and equal to or greater than the opening width in the vertical direction of the opening edge portion 51a of the first lens holder <NUM> and the opening width in the vertical direction of the opening edge portion 52a of the second lens holder <NUM>.

Therefore, as illustrated in <FIG>, when viewing the lens portion <NUM> in a front view, the circuit board <NUM> is positioned over the entire surface of the lens portion <NUM>, so the end of the circuit board <NUM> is not visually recognized. Thus, the appearance is able to be even further improved.

Moreover, in the present embodiment, the circuit board <NUM> is a heat dissipation circuit board, so by increasing the surface area of the circuit board <NUM> in this way, heat dissipation is able to be increased.

Meanwhile, the circuit board <NUM> is on the entire surface of the lens portion <NUM>, so when coloring the surface of this circuit board <NUM> on which the light-emitting chips <NUM> are provided, this color is reflected onto the lens portion <NUM>, so the appearance of the lens portion <NUM> can be controlled.

For example, when it is desirable that the lens portion <NUM> not stand out when the light-emitting chips <NUM> are not illuminated, the color of the surface of the circuit board <NUM> on which the light-emitting chips <NUM> are provided may be black.

Note that when colored black in this way, heat absorption also improves, so heat dissipation efficiency can be improved.

On the other hand, when the color of the surface of the circuit board <NUM> on which the light-emitting chips <NUM> are provided is white, the lens portion <NUM> can be made to appear whitish, so an appearance with a clear look can be obtained.

From the point of appearance, a clear look is often desired, so it is considered preferable to have the color of the surface of the circuit board <NUM> on which the light-emitting chips <NUM> are provided be white.

Incidentally, if the circuit board <NUM> fills up the entire inside of the lens portion <NUM> when viewed from the front, as in the second embodiment, then behind the circuit board <NUM> will naturally not be visibly recognized, as is evident from <FIG>.

Therefore, as illustrated in <FIG>, cutouts <NUM> by which the front surface 21a and the rear surface 21b (see <FIG>) of the base portion <NUM> are communicated are formed in the base portion <NUM>. More specifically, the cutouts <NUM> are formed by cutting out areas between heat dissipating fins <NUM>. In the present embodiment, the cutouts <NUM> are cut out from the lower side toward the upper side in the vertical direction of the base portion <NUM>, to the portion where the light-emitting chips <NUM> of the circuit board <NUM> are positioned, or the vicinity thereof.

Accordingly, when the cooling fan <NUM> (see <FIG>) is provided, as in the present embodiment, wind from the cooling fan <NUM> is able to directly hit the circuit board <NUM> that is a heat dissipation circuit board, thereby enabling the cooling efficiency to be even further increased.

Note that when the cutouts <NUM> are provided in this way, postural stability is maintained by abutting the bent portion 51db of the leg portion 51d (other side leg portion) of the first lens holder <NUM> and the leg portion 52d of the second lens holder <NUM> positioned on the side opposite the electric connector <NUM> with the light-emitting chips <NUM> sandwiched therebetween, against the heat sink <NUM>, instead of fixing them with a screw, as illustrated in <FIG>, and priority may be given to the formation of the cutouts <NUM>.

Further, similar to the first embodiment, a screw hole may be provided in the bent portion 51db of the leg portion 51d (other side leg portion) of the first lens holder <NUM> and the leg portion 52d of the second lens holder <NUM> positioned on the side opposite the electric connector <NUM>, and a screw fixing hole may be provided in a portion of the base portion <NUM> of the heat sink <NUM> corresponding to this screw hole, and fixing by a screw may be performed.

Although the present invention has heretofore been described based on a specific embodiment, the present invention is not limited to the above embodiment.

Claim 1:
A vehicular lamp (<NUM>) comprising:
a semiconductor light source (<NUM>) that has a plurality of light-emitting chips (<NUM>) arranged in a row on a circuit board (<NUM>);
a heat sink (<NUM>) having a base portion (<NUM>) in which the light source (<NUM>) is arranged on a front surface (21a);
a lens (<NUM>) that is arranged in front of the light source (<NUM>) and having a flange portion (<NUM>) on an outer periphery of a lens portion (<NUM>) that radiates light from the light emitting chips (<NUM>) as a predetermined light distribution pattern; and
a lens holder (<NUM>) which has an opening edge portion (51a) that receives the flange portion (<NUM>) and an outer peripheral portion (51b) that extends toward
the heat sink side from the opening edge portion (51a), and which mounts the lens (<NUM>) to the heat sink (<NUM>), characterized in that
the lens portion (<NUM>) is arranged to have a width in a horizontal direction that does not exceed twice the row width of the light-emitting chips (<NUM>) and is equal to or less than a lateral width in the horizontal direction of the circuit board (<NUM>),
an outer shape of the opening edge portion (51a) is made substantially identical to the outer shape of the flange portion (<NUM>) such that an opening width in the horizontal direction of the opening edge portion (51a) is equal to or less than the lateral width in the horizontal direction of the circuit board (<NUM>) , and
the outer peripheral portion (51b) has a shape that widens gradually toward the heat sink side from the opening edge portion (51a), and the lateral width in the horizontal direction of the circuit board (<NUM>) is approximately the same as a width of the widened shape of the outer peripheral portion (51b).