Information
-
Patent Grant
-
6224247
-
Patent Number
6,224,247
-
Date Filed
Thursday, August 20, 199825 years ago
-
Date Issued
Tuesday, May 1, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Sughrue, Mion, Zinn, Macpeak & Seas, PLLC
-
CPC
-
US Classifications
Field of Search
US
- 362 294
- 362 345
- 362 373
- 362 376
- 362 547
-
International Classifications
-
Abstract
Disclosed is a vehicular lamp in which a closed lamp chamber is defined by a lamp body and a front lens, a bulb is disposed within the lamp chamber, and air holes for breathing action are formed in the rear wall of the lamp body. In the vehicular lamp, the air holes are elongated in shape, whereby the air holes each having a large diameter may be formed at desired positions of the rear wall of the lamp body where the air holes do not interfere with various members and components, such as the bulb-exchange opening, the aiming mechanism and the mounting bracket. With the structure, an air circulates within the lamp chamber in such a mode as to prevent moisture from being condensed on the front lens.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a vehicular lamp with breathing air holes formed in the rear wall of a lamp body, which cooperates with a front lens to define a lamp chamber.
2. Related Art
A conventional vehicular lamp of this type is typically illustrated in FIG.
7
. The illustrated lamp is a vehicular headlamp. As shown, a lamp chamber of the headlamp is defined and hermetically closed by a lamp body
1
and a front lens
2
. A reflector with a bulb, which is not shown (as a light source) inserted thereinto is supported by an aiming mechanism A such that it is tiltable back and forth as well as to the right and left. The aiming mechanism A is composed of two aiming screws
3
and
4
and one ball joint
5
. An opening
1
a
for facilitating a bulb exchange is formed in the rear wall of the lamp body
1
, and numeral
8
is a bracket used for fixedly mounting the headlamp on a vehicular body.
An air hole
6
is formed in the rear wall of the lamp body
1
as shown in
FIGS. 7 and 8
. The air hole
6
sets up a communication between the inside and outside of the lamp chamber. In other words, the vehicular lamp or its lamp chamber breathes through the air hole
6
to prevent dew from being formed on the front lens
2
.
As illustrated in
FIG. 8
in an enlarged view, the air hole
6
is defined by a cylindrical portion
1
b
protruded outward from the rear wall of the lamp body
1
. A flexible tube
7
is fit to the cylindrical portion lb: one opened end of a flexible tube
7
is tightly coupled with the cylindrical portion
1
b
, while the other opened end is faced downward. Such a coupling of the flexible tube
7
makes it difficult for dust particles and water to enter the lamp chamber S through the air hole
6
.
The diameter of the air hole
6
is small. Because of this, the breathing action of the lamp chamber is unsatisfactory. Further, the air passage continuous to the air hole
6
is possibly narrowed in its diameter or even closed, for example, where another member is put on the flexible tube
7
. The breathing action, which is unsatisfactory, is thus further deteriorated. In this case, the dew-formation preventing effect is also deteriorated, as a matter of course.
One solution for this problem is to increase the diameter of the air hole
6
(which is circular in cross section) and the inside diameter of the flexible tube
7
.
The rear wall of the lamp body
1
is generally curved in shape. Further, various members and components, such as the bulb-exchange opening
1
a
, the aiming mechanism A and the mounting bracket, are attached to the rear wall of the lamp body. For this reason, it is technically difficult to form the air hole
6
of the sufficiently large diameter at a desired location on the rear wall of the lamp body
1
without interfering with the above members and components.
SUMMARY OF THE INVENTION
The present invention was made in view of the foregoing difficulties accompanying the conventional vehicular lamp. Accordingly, an object of the present invention is to provide a vehicular lamp in which the air holes each having a sufficiently large diameter are formed at desired positions of the rear wall of the lamp body.
The above and other objects can be achieved by a provision of a vehicular lamp which, according to the present invention, includes a closed lamp chamber defined by a lamp body and a front lens, a light source disposed within the lamp chamber, and air holes for breathing action formed in the rear wall of the lamp body, wherein the air holes are formed by an elongating hole.
The rear wall of the lamp body is generally curved in shape, and hence includes a less flat area. Further, a light-source-exchange opening is formed in the rear wall, a bracket for mounting the vehicular lamp on a vehicle body is mounted on the rear wall while being extended outward therefrom. Further, the aiming mechanism for controlling the optical axis of the vehicular lamp sometimes is mounted on the rear wall. The formation of the opening and the attachment of the bracket and the aiming mechanism make it difficult to form the air hole (circular in cross section) of the sufficiently large diameter at a desired location on the rear wall of the lamp body without interfering with the other members and components of the lamp. This difficulty is overcome when the air holes are elongated in shape, however. To form a circular hole, a flat area equal to the area defined by the diameter of the circular hole is required. In this case, if the elongated hole is horizontally (vertically) oriented or elongated, a space extending in the horizontal (vertical) direction is large, but a space extending in the vertical (horizontal) direction is small. Therefore, a design freedom on the locations to form the air holes is added. Further, the elongating hole is equivalent to the hole whose diameter is increased, in its area.
According to another aspect of the invention, in the vehicular lamp each air hole is formed with a cylindrical upstanding wall passing through the rear wall of the lamp body, while being protruded rearward of the rear wall, a dust-blocking filter is put in the upstanding wall, and a rib for preventing the filter from slipping off the upstanding wall into the lamp chamber is provided on the front side of the upstanding wall, while extending along and in the lengthwise direction of the air holes.
Water and dust particles going to the inside of the lamp chamber through the air holes are blocked by the dust-blocking filter contained in the upstanding wall (air hole). Water that is splashed upward and will enter the lamp chamber through the air hole is blocked by the cylindrical upstanding wall protruding rearward of the rear wall of the lamp body before it reaches the dust-blocking filter. Since the filter is supported at its peripheral edge by the cylindrical upstanding wall, it is reliably held within the upstanding wall.
The rib prevents the filter from slipping off the upstanding wall into the lamp chamber. The rib extends along and in the lengthwise direction of the air hole. With provision of the rib, the shorter diameter of the elongated hole is reduced to make the slipping-off prevention more reliable.
Further, according to the present invention, the front end of the upstanding wall protrudes into the lamp chamber.
The cylindrical upstanding wall containing the dust-blocking filter protrudes to the front of the rear wall of the lamp body, so that the upstanding wall protrudes less from the rear side of the lamp body. With this structure, the cylindrical upstanding wall protrudes into the lamp chamber and out of the rear of the lamp chamber. Therefore, the space on the rear side of the lamp body is correspondingly broadened.
According to another aspect of the invention, the vehicular lamp is characterized in that
A) each air hole is covered with an air passage housing for defining labyrinthine air passages continuous to the outside, and
B) the air passage housing includes
a) a second upstanding wall having a cut-out in the bottom and being disposed around the upstanding wall,
b) a third upstanding wall having a cut-out in the bottom and being disposed around the second upstanding wall, the cut-out of the third upstanding wall being not vertically aligned with the cut-out of the second upstanding wall, and
c) a swing cover extending forward from and along a thinned linear portion serving as a hinge which traverses the upper portion of the third upstanding wall, when the swing cover is lance coupled with the bottom portion of the third upstanding wall, the swing cover covering the end opening of the third upstanding wall.
The labyrinthine air passages in the housing covering the air hole blocks the entering of dust particles and water into the air hole. It is noted that the cut-outs of the second and third upstanding walls, which form the air holes, are formed in their bottom portions. This feature makes it for dust particles and water to enter the inside spaces of those upstanding walls. If entered, the particles and water naturally drop through the cut-offs by their weight, i.e., gravity.
The second and third upstanding walls, and the swing cover, which form the labyrinthine air passages, are formed integrally with the lamp body. This structural feature contributes to reduction of the number of the parts required for constructing the vehicular lamp. The labyrinthine air passages may be constructed in a simple manner that the swing cover is bent and lance coupled with the lower edge of the third upstanding wall. Where the air holes are formed with the upstanding walls, the swing cover functions as a holder member to hold the dust-blocking filters placed in the upstanding walls (air holes).
In addition, the air hole may be provided at a location above and near a light-source-exchange opening.
Air heated by the light source rises, and smoothly flows out of the lamp chamber through the air hole located above and near the light source.
Moreover, in the vehicular lamp of the invention, the air holes are classified into a first air hole being provided at a location above and near a light-source-exchange opening, and a second air hole being provided in one of the right and left portions of the rear wall of the lamp body at a location below the light-source-exchange opening and close to the side end of the right or left portion.
In the vicinity of the light-source-exchange opening, air heated by the light source as a heat source flows outside through the first air hole. Outside air is introduced into the lamp chamber through the second air hole being provided in one of the right and left portions of the rear wall of the lamp body at a location below the light-source-exchange opening and close to the side end of the right or left portion. Therefore, an active convection stream of air flows upward from the location close to the side end of the right or left portion, within the lamp chamber. The air stream flows through the entire space within the lamp chamber.
The first air hole may preferably be oriented horizontally, and the second air hole may preferably be oriented vertically.
The first air hole is horizontally elongated. This structural feature allows the air hole to be formed in region which is narrow in the vertical direction and above and near the light-source-exchange opening. The second air hole is vertically elongated. This structural feature allows the air hole to be formed in region which is narrow in the horizontal direction and close to the side end of the right or left portion of the rear wall of the lamp body.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a front view showing a vehicular headlamp constructed according to the present invention;
FIG. 2
is a horizontal sectional view showing the headlamp taken along a line II—II in
FIG. 1
;
FIG. 3
is a longitudinal sectional view showing the headlamp taken along a line III—III in
FIG. 1
;
FIG. 4
is a rear view showing the headlamp;
FIG. 5
is a longitudinal sectional view showing the headlamp taken along a line V—V in
FIG. 4
;
FIG. 6
is a perspective view showing an air hole and its vicinity on the rear side of the headlamp;
FIG. 7
is a rear view in perspective of a conventional vehicular headlamp; and
FIG. 8
is a longitudinal sectional view showing an air hole and its vicinity on the rear side of the headlamp.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the present invention will now be described with reference to the accompanying drawings.
FIGS. 1 through 6
cooperate to show an embodiment of the present invention:
FIG. 1
is a front view showing a vehicular headlamp constructed according to the present invention;
FIG. 2
is a horizontal sectional view showing the headlamp (taken online II—II in FIG.
1
);
FIG. 3
is a longitudinal sectional view showing the headlamp (taken on line III—III in FIG.
1
);
FIG. 4
is a rear view showing the headlamp;
FIG. 5
is a longitudinal sectional view showing the headlamp (taken on line V—V in FIG.
4
); and
FIG. 6
is a perspective view showing air holes and their vicinity on the rear side of the headlamp.
In those figures, a lamp body
10
is made of synthetic resin. The lamp body
10
is rectangular while being laterally elongated, and opened expanding from the front in the sideways direction. A transparent, curved front lens
11
is attached to the opening of the front of the lamp body
10
, whereby a lamp chamber S is hermetically formed while being laterally rectangular in shape.
Within the lamp chamber S a lamp unit
20
is tiltably supported by an aiming mechanism formed with two aiming screws
12
and
13
and one ball joint
14
. The lamp unit
20
, which is of the reflection type, functions to form a main beam and a low beam.
The lamp unit
20
is constructed with a synthetic resin reflector
22
, a bulb
30
and a shade
40
. The reflector
22
includes a parabolic reflecting surface deposited with aluminum (mirror processed). The bulb
30
as a light source is inserted into and fixed to a bulb insertion hole
23
, which is formed at the rear vertex of the reflector
22
. The shade
40
, for light distribution control, is fixed to the bulb insertion hole
23
by screw means while covering the front of the bulb
30
.
The bulb
30
, made of glass, contains a main-beam filament
31
a
and a low-beam filament
31
b
. In a state that the bulb
30
is fixed to the bulb insertion hole
23
, the reflector
22
is positioned so as to be focused at a mid position between the filaments
31
a
and
31
b
. The main-beam filament
31
a
, when energized, emits a main beam, and the low-beam filament
31
b
, when energized, emits a low beam.
The lamp body
10
includes an upper wall
10
a
, a lower wall
10
b
and a rear wall
10
c
. A bracket
15
is attached onto the upper wall
10
a
. The lamp body is mounted on a vehicle body by means of the bracket
15
. The lower wall
10
b
extends in parallel with the upper wall
10
a
. The rear wall
10
c
, curved rearward, is located between the upper and lower walls
10
a
and
10
b
. An opening
10
d
for bulb replacement is formed in the rear wall
10
c
of the lamp body
10
. A bulb socket
32
of the bulb
30
is protruded rearward through the opening
10
d
. A rubber hood
34
, which is expandable, is located between a cylindrical portion
10
e
forming the opening
10
d
and the bulb socket
32
, to thereby close the rear opening (bulb replacing opening)
10
d
of the lamp body
10
.
The lamp unit
20
is tiltably supported on the lamp body
10
by means of the two aiming screws
12
and
13
and the ball joint
14
. The aiming screws
12
and
13
are rotatably supported on the rear wall
10
c
of the lamp body
10
. A couple of nuts
12
a
and
13
a
, which are to be screwed into the aiming screws
12
and
13
, are mounted onto brackets
22
a
and
22
a
, respectively. Those brackets protrude from the rear surface of the reflector
22
. By turning the aiming screws
12
and
13
, the nuts
12
a
and
13
a
are moved forward and backward along the aiming screws
12
and
13
, respectively. Through the movements of the nuts, the lamp unit
20
is tilted about the horizontal axis Lx and the vertical axis Ly, whereby the optical axis L of the lamp unit
20
is tilted vertically and horizontally as well.
Crown gears
12
b
and
13
b
are integrally provided at the rear ends of the aiming screws
12
and
13
, respectively. The aiming screws
12
and
13
may be turned by turning the crown gears
12
b
and
13
b
, respectively.
An extension reflector
18
ranges from the front opening of the lamp body
10
to the inner side of the front lens
11
, and extends along the latter. The extension reflector
18
has an opening
18
a
, which is located corresponding to the reflector
22
of the lamp unit
20
. The obverse side of the extension reflector
18
is deposited with aluminum (mirror processed), like the reflector
22
. The extension reflector
18
thus mirror processed covers the periphery region of the lamp unit
20
, and with provision of the extension reflector
18
, the entire surface of the lamp chamber S looks like a uniform mirror surface. In this respect, the look of the headlamp is improved.
Three air holes
50
A,
50
B and
50
C (generally represented by numeral
50
) are formed in the rear wall
10
c
of the lamp body
10
. Three air passage housings H
1
, H
2
and H
3
(generally represented by numeral H) are provided covering the air holes
50
. The air holes
50
open into the air passage housings H, respectively. Further, labyrinthine air passages h
1
, h
2
and h
3
(generally designated by h), continuous to the outside, are formed in the air passage housings H, respectively. Communication between the inside and outside of the lamp chamber S is set up through those air holes
50
and labyrinthine air passages h. With those structures, the headlamp breathes to prevent moisture from being condensed on the front lens
11
.
The opening
10
d
for bulb replacement is formed in the rear wall
10
c
as already stated. The rear wall
10
c
includes a central portion
10
c
1
, and depressed portions
10
c
2
and
10
c
3
located on both sides of the central portion
10
c
1
. The central portion
10
c
1
is curved along the reflector
22
. The aiming mechanism and a bracket
16
for fixing the headlamp to the vehicle body, and the like are disposed on those depressed portions
10
c
2
and
10
c
3
. A depressed portion
10
c
4
is located on the left side (when viewed from the rear side of the headlamp) of the aiming-mechanism receiving depressed portion
10
c
2
. A bracket
17
by which the headlamp is mounted onto the vehicle body is protruded from the depressed portion
10
c
4
. The first air hole
50
A and the air passage housing H
1
are provided on the central portion
10
c
1
of the curved rear wall
10
c
of the lamp body. The second air hole
50
B and the air passage housing H
2
, and the second air hole
50
C and the air passage housing H
3
are, respectively, provided on the lower portions of the aiming-mechanism receiving portion (right)
10
c
3
and the bracket-forming depressed portion (left)
10
c
4
.
The first air hole
50
A is horizontally elongated. The housing Hi is rectangular, extending horizontally, like the enlarged air hole
50
A. The housing H
1
is provided at a location above and near the bulb-exchange opening
10
d
in the central portion
10
c
1
of the lamp body rear wall. The vertical length of the housing H
1
is shorter than the horizontal length thereof.
The second air holes
50
B and
50
C are vertically elongated. The housings H
2
and H
3
are rectangular while oriented vertically, like the enlarged air holes
50
B and
50
C. The housings H
2
and H
3
are provided at locations below the bulb-exchange openings
10
d
in the right portion
10
c
3
and the left portion
10
c
4
of the lamp body rear wall.
The air present around and heated by the bulb
30
flows upward within the lamp chamber S, and smoothly flows out of the lamp chamber through the first air hole
50
A. At the same time, outside air is introduced into the lamp chamber through the second air holes
50
B and
50
C. The result is that a stream of air by convection is formed within the lamp chamber. Thus, the lamp chamber S breathes through the air holes
50
(
50
A,
50
B and
50
C), so that no moisture is condensed on the front lens
11
.
As shown in
FIG. 5
, an air passage hole
60
is formed in the rear wall of the reflector
22
at a position confronting the first air hole
50
A. Air heated on the inner side of the reflector
22
passes outside the reflector
22
and flows to the first air hole
50
A, and further passes through the air passage hole
60
and flows to the first air hole
50
A (arrows in FIG.
5
). In this way, the breathing action of the lamp chamber is activated.
The air holes
50
(
50
A,
50
B and
50
C) are elongated holes of large opening areas, whereby a sufficient amount of air flows through the lamp chamber S. The following air current is formed within the lamp chamber S: Outside air introduced into the lamp chamber S through the second air holes
50
B and
50
C, which are located in the lower portion within the lamp chamber S and closer to the right and left sides of the same, and is discharged out of the lamp chamber S through the first air hole
50
A located at the central position in the upper portion within the lamp chamber S. The unique structure of the invention, which causes the above air current, successfully solves the following problem of the conventional headlamp: the convection air current C is entirely formed within the lamp chamber S; the warm air insufficiently circulates by convection within the lamp chamber S; and therefore, moisture is liable to be condensed at the corners of the front lens
11
.
A cylindrical upstanding wall
51
passing through the rear wall
10
c
of the lamp body
10
forms each air hole
50
. The upstanding wall
51
protruding rearward from the rear wall
10
c
almost blocks the entering of dust and water into the air hole
50
located within the upstanding wall
51
. Further, a sponge-like filter
53
is put in the upstanding wall
51
. The filter
53
enhances the dust- and water blocking function of the upstanding wall
51
. Each of the air holes
50
A,
50
B and
50
C is oval in cross section having radius R at both long diameter ends thereof. Since the filter
53
fits in the oval air hole
50
, the filter can fill the entire space of the hole
50
without creating any gap. The feature improves water and dust proof performance.
A rib
52
is provided on the front side of the upstanding wall
51
while extending along each air hole
50
. The rib
52
prevents the filter
53
from slipping off the upstanding wall
51
into the lamp chamber S. The rib
52
extends in the lengthwise direction of the air hole (elongated hole)
50
, so that the short diameter width of the elongated hole is further reduced and the filter
53
is more reliably held within the upstanding wall
51
.
The front end
51
a
of the upstanding wall
51
, which forms the air holes
50
, is protrudes into the lamp chamber S. In other words, the upstanding wall
51
protrudes less to the rear side of the lamp body. Therefore, the air passage housing H, provided covering the upstanding wall
51
, protrudes less correspondingly.
A second upstanding wall
54
and a third upstanding wall
56
are further provided. The second upstanding wall
54
is disposed around the upstanding wall
51
of the rear wall
10
c
of the lamp body. The diameter of the opening of the second upstanding wall
54
is larger than that of the upstanding wall
51
. The bottom portion of the second upstanding wall
54
is cut out in part. The second upstanding wall
54
is higher than the upstanding wall
51
. The third upstanding wall
56
, rectangular in cross section, is disposed around the second upstanding wall
54
. The bottom portion of the third upstanding wall
56
is cut out in part. The third upstanding wall
56
is higher than the second upstanding wall
54
.
It is noted that the cut-outs
55
and
57
of the second and third upstanding walls
54
and
56
are formed in the bottom portions of those upstanding walls. With provision of the cut-outs, even if water enters into the inside spaces of those upstanding walls
54
and
56
, it is naturally discharged through those cut-outs.
The cut-outs
55
and
57
of the second and third upstanding walls
54
and
56
are arranged such that those cut-outs are not vertically aligned with each other. Since the upstanding walls are thus arranged on their cut-outs, if water enters through the cut-out
57
of the third upstanding wall
56
, it rarely reaches the cut-out
55
of the second upstanding wall
54
.
A thinned linear portion serving as a hinge
58
traverses the upper portion of the third upstanding wall
56
. A swing cover
59
extends forward from and along the hinge
58
. The swing cover
59
is used for covering the end opening of the third upstanding wall
56
. The swing cover
59
has an engaging protrusion
59
a at its free end. When the swing cover
59
is turned down to close the end opening of the third upstanding wall
56
, the engaging protrusion
59
a
engages into an engaging hole
56
a
formed in the lower or bottom portion of the third upstanding wall
56
.
The swing cover
59
is bent and turned down about the hinge
58
, and the engaging protrusion
59
a
of the swing cover
59
is brought into engagement (lance engagement) with the engaging hole
56
a
of the third upstanding wall
56
. Then, the end opening of the third upstanding wall
56
is closed with the swing cover
59
, to thereby form the labyrinthine air passages h (h
1
, h
2
, h
3
) which are continuous to the lamp chamber S via the air holes
50
and to the outside of the lamp chamber S, through the cut-out
57
. Also in the closing state of the swing cover
59
, the dust-blocking filter
53
is pushed by the swing cover
59
and firmly held within the upstanding wall
51
.
Thus, the labyrinthine air passages (h
1
, h
2
, h
3
) allowing the air holes
50
(
50
a
,
50
B,
50
C) to be continuous to the exterior are formed by the second upstanding wall
54
, the third upstanding wall
56
and the swing cover
59
, which form the air passage housings H.
A rib
59
b
with a knob is attached to and along the free end of the swing cover
59
. The rib
59
b
is helpful when the swing cover
59
is closed. To close the swing cover
59
, the flat of a worker's finger is put on the rib
59
b
to be immovable (as indicated by a phantom line in FIG.
5
). Therefore, a pressing force by the finger is efficiently transmitted to the swing cover
59
to bend and turn the swing cover
59
, so that the engaging protrusion
59
a
fits smoothly into the engaging hole
56
a.
It is noted that the air passage housings H (H
1
, H
2
, H
3
) are formed integrally with the lamp body
10
, while the flexible tube is separated from the lamp body and attached thereto in the conventional device. This structural feature contributes to a reduction of the number of the parts required for constructing the vehicular lamp. The labyrinthine air passages h (h
1
, h
2
, h
3
) may be constructed in a simple manner such that the swing cover
59
is bent and lance coupled with the lower edge of the third upstanding wall. In this respect, the air passage constructing work is very easy.
While in the embodiment mentioned above, the invention is incorporated into the vehicular headlamp, it is clear that the invention is applicable to any other suitable vehicular lamp in a similar way.
As seen from the foregoing description, in the vehicular lamp of the invention, the air holes for breathing action are the elongated holes.
The air holes each having a sufficiently large diameter may be formed at given locations on the rear wall of the lamp body without interfering with the light-source-exchange opening, and the like. Therefore, a satisfactory air flowing between the inside and outside of the lamp chamber is secured, and hence a reliable prevention of formation of the dew on the front lens is secured. There is less restriction on the locations to form the air holes so as to increase design freedom in designing the lamp body.
Further, in the vehicular lamp of the invention, dust particles and water are blocked by the dust-blocking filter put in the upstanding wall (air hole). The dust and water blocking function in the air hole is guaranteed for a long time. The dust-blocking filter is tightly put in the upstanding wall, providing a reliable dust/water blocking function.
Further, the rib prevents the dust-blocking filter put in the upstanding wall (air hole) from slipping off the upstanding wall into the lamp chamber. The dust-blocking filter may be put within the upstanding wall in a simple manner, and stably be held therewithin for a long time.
Further, in the vehicular lamp of the invention, the upstanding wall protrudes less from the rear side of the lamp body, and hence the space on the rear side of the lamp body is correspondingly broadened. This reduces the possibility that the upstanding wall interferes with other members and the like.
In the vehicular lamp, further, the labyrinthine air passage communicating with the air hole within the air passage housing reliably blocks the dust particles and water from entering the air hole.
The air hole is located higher than the air passage, which provides a communication between the inside and outside of the air passage housing. This feature ensures the dust-and water-blocking function for the air hole.
The labyrinthine air passage forming member (housing) is formed integrally with the lamp body. This feature contributes to a reduction of the number of required component parts. The lance coupling enables a mere closing of the swing cover to form the air passage. This leads to simplification of the headlamp assembly.
In the vehicular lamp, air heated by the light source rises, and smoothly flows out of the lamp chamber through the air hole located above and near the light source.
In the vehicular lamp, an active stream of air flows from a location below the light-source-exchange opening and close to the side end of the right or left portion to the central portion above the lamp chamber. Therefore, the air stream flows through the entire space within the lamp chamber.
In the lamp of the invention, moreover, the first air hole formed in the region which is narrow in the vertical direction and above and near the light-source-exchange opening, is horizontally oriented, and the second air hole formed in the region which is narrow in the horizontal direction and close to the side end of the right or left portion of the rear wall of the lamp body, is vertically oriented. With this structure, the air hole of sufficiently large diameter may be formed at a desired location on the rear wall of the lamp body, without interfering with the bulb-exchange opening, the aiming mechanism, the mounting bracket, and the like.
Claims
- 1. A vehicular lamp comprising:a lamp body having a front opening; a front lens coupled to the front opening of the lamp body; a closed lamp chamber defined by the lamp body and the front lens; a light source disposed within said lamp chamber; and first and second air holes formed in the rear wall of said lamp body, said first and second air holes being elongated in shape, wherein A) each of said first and second air holes is covered with an air passage housing for defining labyrinthine air passages continuous to the outside of the lamp chamber, said air passage housing of said first air hole being elongated horizontally in the same direction in which said first air hole is elongated and said air passage housing of said second air hole being elongated vertically in the same direction in which said second air hole is elongated, so that said air passage housings are elongated in directions that are perpendicular to each other, wherein said air passage housings are rectangular-shaped housings; and B) said air passage housings comprising: a) a second upstanding wall having a cut-out in a bottom portion and being disposed around an upstanding wall, b) a third upstanding wall having a cut-out in a bottom portion and being disposed around said second upstanding wall, said cut-out of said third upstanding wall being not horizontally aligned with said cut-out of said second upstanding wall, and c) a swing cover being extended rearward from and along a thinned linear portion serving as a hinge which traverses an upper portion of said third upstanding wall, when said swing cover is lance coupled with the bottom portion of said third upstanding wall, said swing cover covering an end opening of said third upstanding wall.
- 2. The vehicular lamp according to claim 1, wherein each of said first and second air holes comprises a cylindrical upstanding wall penetrating through the rear wall of said lamp body so as to protrude towards the outside of the lamp chamber, a dust-blocking filter disposed in said upstanding wall, and a rib disposed on the front side of said upstanding wall, extending in the lengthwise direction of elongation of said first and second air holes.
- 3. The vehicular lamp according to claim 2, wherein said front end of said upstanding wall protrudes into said lamp chamber.
- 4. The vehicular lamp according to claim 1, wherein one of said first and second air holes is provided at a location above and near a light-source-exchange opening.
- 5. The vehicular lamp according to claim 1, wherein said first air hole is provided at a location above and near a light-source-exchange opening, and a second air hole is provided in one of right and left portions of the rear wall of said lamp body at a location below said light-source-exchange opening and close to a side end of the right or left portion.
- 6. The vehicular lamp according to claim 1, wherein each of said first and second air holes is oval in cross section, and comprises an upstanding wall, and further comprises a filter filled in at least one of said oval air holes.
- 7. The vehicular lamp according to claim 1, further comprising:a reflector disposed within said closed lamp chamber, wherein an air passage hole is formed in said reflector at a position confronting said first air hole.
- 8. A vehicular lamp comprising:a lamp body having a front opening; a front lens coupled to the front opening of the lamp body; a closed lamp chamber defined by the lamp body and the front lens; a light source disposed within said lamp chamber; and air holes formed in a rear wall of said lamp body, said air holes being elongated in shape, wherein said air holes are covered with an air passage housing for defining labyrinthine air passages continuous to the outside of the lamp chamber, said air passage housing being rectangular-shaped and elongated in the same direction in which said air holes are elongated.
Priority Claims (1)
Number |
Date |
Country |
Kind |
9-239366 |
Sep 1997 |
JP |
|
US Referenced Citations (9)