Headlight for vehicle

A vehicular headlight having an inner lens and a hood, which is painted to block light, integrally made of a light-transmissible resin so that no opening is formed between the inner lens and the hood. As a result, no light can leak through such an opening, and the adjustment gap between the inner lens and reflector cannot be seen through the opening. Since the inner lens and the hood are constituted by a single component, the number of components of the headlight is reduced to decrease the number of steps of assembly thereof.

BACKGROUND OF THE INVENTION 
The present invention relates generally to a vehicular headlight, and more 
particularly relates to the construction of an ornamental frame provided 
around an inner lens and which is referred to as hood. 
In a conventional vehicular headlight, light emitted from the filament of a 
bulb (light source) is reflected by a reflector so that the light is 
directed out through an inner lens and an outer lens. The inner lens is 
disposed between the outer lens and the open side of the reflector, 
thereby dividing the inner space of the headlight into an outer lens side 
and a reflector side. An ornamental frame, referred to as hood, is 
provided between the inner and the outer lenses. The hood is shaped in 
such a manner that it appears like an extension of the front edge of the 
reflector. The hood functions so that the inner portion of the headlight 
near the inner and the outer lenses is prevented from being seen from 
outside the headlight, which would degrade the appearance of the 
headlight. The hood is provided separately from the other components of 
the headlight and then attached to the body of the headlight as well as 
the inner and the outer lenses. 
In general, there are two types of vehicular lamps producing parallel light 
beams. One lamp type employs a parabolic reflector, and the other an 
elliptic reflector and a projection lens. The latter type is so-called a 
projection lamp. Projection lamps are advantageous in that they can be 
made smaller in size than the former type, as disclosed in U.S. Pats. Nos. 
4,677,532, 2,338,901 and 1,581,581. 
In a projection lamp, a light source is positioned substantially at the 
first focal point of the elliptic reflector. The light rays emitted from 
the light source are reflected by the elliptic reflector and focused by 
the projection lens. The projection lens is located substantially at the 
second focal point of the elliptic reflector. The light rays passed 
through the projection lens are gathered along an optical axis and form a 
required pattern of light. 
Conventionally, since the projection lens is small in size, the lens is 
covered by an outer lens which is larger in size than the projection lens, 
and protected by a protector which is mounted along the circumference of 
the lens in order to obtain a good perspective with respect to the vehicle 
body when viewed from the outside. 
Since the hood and inner lens of the conventional headlight mentioned above 
are separately provided components, an opening is usually formed between 
the hood and the inner lens at the time of assembly of the headlight. The 
reflector must be able to swing through a small angle relative to the body 
of the vehicle so as to adjust the angle of the direction of emission of 
the light from the headlight. That is, to enable the adjustment, an 
adjustment gap is provided between the reflector and the inner lens. If 
the opening is present between the hood and the inner lens, the adjustment 
gap can be seen through the opening, degrading the appearance of the 
headlight. Moreover, the opening lets light leak. Therefore, the presence 
of this opening produces undesirable effects. 
Furthermore, since the hood is a separately provided component, the number 
of components of the headlight is large, as is the number of steps of 
assembly of the headlight. Yet further, if the space between the outer 
lens side and the reflector side is sealed or narrowed, the inner surface 
of the inner lens or outer lens may be fogged by humid air heated by the 
bulb. Such fogging creates a problem in that the light rays emitted by the 
light source are diffused in random directions, thereby causing 
discomforting glare or reducing the amount of output light. Moreover, 
since the space surrounded by the projection lens, protector and outer 
lens is heated by the bulb to a relatively high temperature, the protector 
and outer lens, which are ordinarily made from a resin, can be deformed 
due to the heat. 
SUMMARY OF THE INVENTION 
The present invention was made in order to solve the above-mentioned 
problems. Accordingly, it is an object of the present invention to provide 
a vehicular headlight in which no opening is present between the hood and 
inner lens so that light is prevented from leaking, the adjustment gap 
between the reflector and the inner lens is prevented from being seen, and 
the number of components of the headlight is reduced to decrease the 
number of steps of assembly of the headlight. 
It is another object of the invention to provide a vehicular headlamp 
capable of preventing the inner surface of the inner lens and outer lens 
from being fogged. 
It is still another object to provide a vehicular headlamp in which the 
protector and outer lens are not deformed by the heat of the bulb. 
In the headlight of the invention, the light from a light source is 
reflected by a reflector so that the light is directed out through the 
inner lens and an outer lens. The hood is provided between the inner and 
the outer lenses and extends around the inner lens. The inner lens and the 
hood are integrally made of a light-transmissible resin. The hood is 
painted to block light. 
In the headlight provided in accordance with the present invention in which 
the inner lens and the hood are integrally made of the light-transmissible 
resin and the hood is painted to block the light, the hood serves as an 
ornamental frame through which the light cannot be transmitted. Since the 
inner lens and the hood are integrally formed with each other, no opening 
is required between them so that the light is prevented from leaking 
through between those two members, the adjustment gap between the 
reflector and the inner lens cannot be seen from outside the headlight, 
and the number of components of the headlight is reduced to decrease the 
number of steps of assembly thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Preferred embodiments of the present invention will be hereafter described 
in detail with reference to the attached drawings. 
FIGS. 1-17 show a four-bulb combination headlight of a preferred embodiment 
of the invention. This headlight is attached to the body of a vehicle at 
the left-hand portion thereof as viewed by the driver. 
As shown in FIG. 6, a high-beam lamp 6 and a low-beam lamp 8 are provided 
in the body of the headlight, which is attached to the body 2 of the 
vehicle. The lamps 6 and 8 have bulbs 10 and 12, and reflectors 14 and 16, 
respectively, for reflecting light emitted from the bulbs. The reflectors 
14 and 16 are attached with swing angle adjustment mechanisms 18 and 20 to 
the headlight body 4 so that the reflectors can be swung by prescribed 
small angles to adjust the orientation of the optical axes thereof. The 
reflected light is directed out forward through an inner lens 22 or a 
condensing lens 24 so that the light has a prescribed distribution or 
range. As for the low-beam lamp 8, the portion of the light not necessary 
for the output light distribution pattern complying with the standards of 
the country where the headlight is used is blocked by a shade 17, while 
the remaining portion of the light is transmitted through the condensing 
lens 24. The lens 24 is attached with a holder 26 to the reflector 16, 
which is an ellipsoidal reflector. A protector 28 is provided in front of 
the condensing lens 24 so as to protect the portions of the headlight near 
the lens from the heat generated by the bulb. The protector 28 is attached 
to the inner lens 22. The inner lens 22 extends not only in front of the 
reflector 14 of the high-beam lamp 6 but also in front of a clearance lamp 
30 provided at the left side of the headlight, as shown in FIGS. 6 and 13. 
An outer lens 32 is provided in front of the inner lens 22 and the 
condensing lens 24, extending continuously to the outside curved surface 
of the body of the vehicle so as to provide the appearance of constituting 
a part of the overall outside surface of the vehicle body, as dictated by 
design considerations. 
The components of the headlight will now be described in greater detail. 
The reflectors 14 and 16 are described first. The reflector 14 of the 
high-beam lamp 6 is a paraboloidal reflector as shown in FIG. 11. The 
reflector 16 of the low-beam lamp 8 is an ellipsoidal reflector as shown 
in FIG. 8. The central portions of the reflectors 14 and 16 have bulb 
insertion holes 34 and 34' in which the bulbs 10 and 12 of the lamps 6 and 
8 are fitted. The shade 17 is provided in front of the reflector 16 so as 
to block a part of the light from the bulb 12 to effect the prescribed 
light distribution pattern with a cut outline. 
The reflectors 14 and 16 are attached with the swing angle adjustment 
mechanisms 18 and 20 to the body 4 of the headlight. Each of the 
adjustment mechanisms 18 and 20 includes a fulcrum portion 36 or 36' for 
supporting the reflector 14 or 16 in such a manner as to make it possible 
to swing the reflector in all directions, and two adjusting support 
portions 38 or 38' for supporting the reflector. Thus, the reflector is 
supported at three points, as shown in FIGS. 7, 9, 10 and 12. The fulcrum 
portion 36 or 36' shown in FIG. 12 or 7 is formed by a ball 42 or 42' at 
the tip of a pivot 40 or 40' attached to the headlight body 4, and a pivot 
bearer 44 or 44' attached to the reflector 14 or 16 and supporting the 
ball. The fulcrum portions 36 and 36' serve as fulcra to change the angles 
of the optical axes of the reflectors 14 and 16, respectively. 
The adjusting support portions 38 or 38' shown in FIG. 10 or 9 are 
implemented with adjusting screws 46 or 46' extending through the 
headlight body 4, and self-locking 48 or 48' threadedly engaged with the 
tip portions of the screws and secured to the reflector 14 or 16. Flanges 
50 and 50' are integrally formed on the adjusting screws 46 and 46' and 
located in contact with the back of the headlight body 4, and fasteners 54 
and 54' are press-fitted in the grooves 52 and 52' of the screws and 
located in contact with the inside of the headlight body, so that the 
headlight body is pinched between the flanges and the fasteners. As a 
result, the adjusting screws 46 and 46' are not moved in the axial 
directions thereof relative to the headlight body 4 when the screws are 
turned. The self-locking nuts 48 and 48' secured to the reflectors 14 and 
16 can be moved in the axial directions of the nuts by the tips of the 
adjusting screws 46 and 46' by turning the screws. Accordingly, each of 
the reflectors 14 and 16 can be swung about a vertical axis by turning one 
of the two adjusting screws 46 or 46', and be swung about a horizontal 
axis in the right-to-left direction of the body of the vehicle by turning 
the other of the two adjusting screws. Thus, the angle of the direction of 
emission of light from the lamp 6 or 8 can be finely adjusted. 
The lamp bulbs 10 and 12 are inserted into the bulb insertion holes 34 and 
34, of the reflectors 14 and 16 from behind, as shown in FIGS. 6, 8 and 
11. Setting springs 56 and 56' are provided so that the end portions of 
the springs whose other end portions are engaged on the reflectors 14 and 
16 at the edges thereof on the bulb insertion holes 34 and 34' so as to be 
swingable are manually deformed by pushing. The springs 56 and 56' are 
engaged on the engagement portions of the reflectors at the edges thereof 
on the holes. As a result, the central portions of the setting springs 56 
and 56' push the flanges 58 and 58' of the bulbs 10 and 12 from behind 
onto the reflectors 14 and 16 at the edges thereof on the bulb insertion 
holes 34 and 34' to fasten the bulbs to the reflectors. 
The bulbs 10 and 12 have bases 60 and 60' behind the flanges 58 and 58'. 
Electric power is applied to terminals 62 and 62' at the bases 60 and 60' 
to cause the filaments of the bulbs to emit light. 
The inner lens 22 is provided at the open fronts of the reflectors 14 and 
16 and extends from the high-beam lamp 6 to the clearance lamp 30, as 
shown in FIGS. 6, 11 and 13. The inner lens 22 is made of a 
light-transmissible polycarbonate resin. As shown in FIG. 6, the portion 
of the lens 22 which corresponds to the low-beam lamp 8 has a hole 64 for 
fitting the protector 28. The inner lens 22 has an ornamental frame 
portion 66, referred to as hood, located at the high-beam lamp 6. The hood 
66 is painted gray, as indicated at 68, to block a part of the light from 
the bulb 10 of the lamp 6. 
The inner lens 22 and the hood 66 are integrally formed with each other to 
reduce the number of components of the headlight to decrease the number of 
the steps of assembly thereof. Also, no opening is formed between the lens 
and the hood to improve the appearance of those elements as viewed from 
outside the headlight with respect to the case where they are separately 
provided. Since no opening is present between the inner lens 22 and the 
hood 66, an adjustment gap 70 is provided between the reflector 14 and the 
inner lens 22 so as to enable the adjustment of the angle of the direction 
of emission of light from the lamp 6. However, the gap 70 cannot be seen 
from outside the headlight. As a result, the headlight has a better 
overall appearance. Since no opening is present between the inner lens 22 
and the hood 66, light does not leak through such an opening. 
The upper portion of the inner lens 22 has air holes 72 for preventing the 
lens from collecting moisture, as shown in FIGS. 1 and 10. Air between the 
inner lens 22 and the outer lens 32 is allowed to flow into the interior 
of the headlight body 4 through the air holes 72 to prevent the inside 
surfaces of the inner and the outer lenses from collecting moisture 
thereon and to reduce the difference between the temperature of the inner 
lens and that of the surrounding ambient, thus preventing the inner lens 
from being thermally deformed. 
To attach the inner lens 22 to the headlight body 4, the inner lens is 
fastened to the outer lens 32 by screws 80 as shown in FIG. 16, and the 
sealed edge portion 76 of the inner lens is fitted together with a sealant 
78 in the sealing groove 74 of the headlight body 4, as shown in FIG. 14. 
At the time of attachment of the inner lens 22 to the headlight, the 
sealed edge portion 102 of the outer lens 32 is fitted together with a 
sealant 106 in the sealing groove 104 of the headlight body 4. Since the 
inner and the outer lens 22 and 32 are coupled to each other by the screws 
80 in advance, the lenses can be efficiently attached to the headlight 
body 4. 
The protector 28 is fitted at the hole 64 of the central portion of the 
inner lens 22, and attached to the inside of the lens by screws 88, as 
shown in FIG. 6. The protector 28 divides the space between the condensing 
lens 24 and the headlight body 4 and that between the condensing lens and 
the outer lens 32 so that the components around the condensing lens are 
protected from heat. The protector 28 is preferably made of die-cast 
aluminum so that heat in the space surrounded by the condensing lens 24, 
the protector and the outer lens 32 is transmitted out through the 
protector to lower the temperature of the space and thus prevent the 
protector and the outer lens from being thermally deformed. 
The protector 28 may be made of another metal. For example, the protector 
28 may be made of a metal sheet shaped cylindrically. The protector 28 is 
shaped as a truncated cone cut obliquely to the axis thereof at the 
smaller and larger diameters. An adjustment gap 90 is provided between the 
protector 28 and the condensing lens 24 at the inner end of the protector 
so as to enable the adjustment of the angle of the direction of emission 
of light from the bulb 12 of the low-beam lamp 8. Air between the 
condensing lens 24 and the outer lens 32 can flow into the interior of the 
headlight body 4 through the adjustment gap 90. 
The holder 26 is attached by screws 92 to the front end portion of the 
ellipsoidal reflector 16 of the low-beam lamp 8. The holder 26, which is 
made of die-cast aluminum, supports the condensing lens 24. The holder 26 
is nearly cylindrically shaped as a whole. A lens fitting metal support 94 
is attached to the front end portion of the holder 26 by screws 96. The 
front end portion of the metal support 94 is bent in nearly an L shape, 
which portion holds the peripheral flange 98 of the condensing lens 24 at 
the front surface of the flange. The reflector 16, the shade 17, the 
holder 26, the metal holder 94 and the condensing lens 24 are thus coupled 
to each other. 
The outer lens 32, which is a monolithic member made of a transparent 
polycarbonate resin, covers the fronts of the inner lens 22 and the 
condensing lens 24. The vertical sectional shape of the front portion of 
the outer lens 32, which is shown in FIGS. 7, 8, 9 and 10, is such that 
the shape is not continuous in radius of curvature and the front portion 
has a vertically central bent part 100 having a small radius of curvature. 
The bent part 100 is located so as to correspond to the condensing lens 
24, as shown in FIG. 8. The bent part 100 acts as a lens due to the 
bending thereof to cancel the chromatic aberration of the condensing lens 
24. Chromatic aberration is a phenomenon which occurs due to the spherical 
surface of the condensing lens 24 and is such that white light is bluishly 
colored because the refractive index of the condensing lens differs for 
different wavelengths or colors of light from the lamp bulb 12 so as to 
slightly vary the focal length of the lens for the different wavelengths 
or colors of rays. The bent part 100 acts as a lens to cause reverse 
chromatic aberration to offset the chromatic aberration of the condensing 
lens 24 so that light is emitted from the headlight without being bluish 
colored. 
The sealed edge portion 102 of the outer lens 32 is fitted together with 
the sealant 106 in the sealing groove 104 of the edge portion of the 
headlight body 4 so that the outer lens is attached to the headlight body, 
as shown in FIGS. 6 and 14. To accurately perform the attachment, a pin 
108 is integrally formed on the outer lens 32 in parallel with the sealed 
edge portion 102 at a part of the outer lens which is greatly curved and 
thinned to the corner of the body of the vehicle, and a pin hole, into 
which the pin is inserted, is provided in the headlight body 4, as shown 
in FIGS. 6 and 13. A jut 110, in which the pin hole is provided, is formed 
at the outside of the sealing groove 104 of the headlight body 4. 
For the attachment operation, the sealed edge portion 102 is fitted into 
the sealing groove 104, and the pin 108 is inserted into the pin hole. 
Since the width of the sealed edge portion 102 is smaller than that of the 
sealing groove 104, the sealant 106 is filled in the gap between the 
portion and the inside of the groove. The sealant 106 is of a type which 
softens readily at high temperatures. Thus, it would be difficult to keep 
the sealed edge portion 102 positioned in the direction perpendicular to 
the surface of the portion. Moreover, the edge portion of the outer lens 
32 is thinned and curved such that the portion is easy to bend to be 
displaced in the transverse direction of the vehicle. For such reasons, in 
a conventional headlight, it is difficult to retain such a sealed edge 
portion positioned in such a sealing groove. 
However, in this embodiment, the pin 108 is engaged in the pin hole to make 
it easy to keep the sealed edge portion 102 positioned in the sealing 
groove 104. After the outer lens 32 is thus attached to the headlight body 
4, clips 112, which are curved spring plates, are provided on five parts 
of the edge joint of the outer lens and the headlight body so that the 
clips clamp the projections 114 of the lens and those 116 of the body to 
each other, as shown in FIG. 11. The sealed edge portion 102 is pushed in 
the direction of depth of the sealing groove 104 due to the clamping 
force, while the portion would not be firmly held positioned in the 
direction of width of the groove. In other words, the outer lens 32 would 
be likely to be displaced relative to the headlight body 4 in the 
transverse direction of the vehicle by a distance corresponding to the 
thickness of the sealant 106 between the sealed edge portion 102 of the 
lens and the inside of the sealing groove 104 of the body. However, the 
pin 108 is inserted into the pin hole of the jut 110 so that the outer 
lens 32 is prevented from being displaced in the direction of the width of 
the sealing groove 104. The pin 108 and the pin hole are thus provided in 
the side portion of the headlight to prevent the outer lens 32 and the 
headlight body 4 from being displaced relative to each other, causing 
unwanted gaps. 
As described above, the headlight body 4 and the outer lens 32 are attached 
to each other by engaging the sealing edge portion of the lens in the 
sealing groove 104 of the body. The sealing groove 104 is provided in the 
outer portion of the headlight body 4 outside the thick portion thereof, 
as shown in FIG. 8. The headlight body 4 has a projecting part on the 
outside of the body so as to define the sealing groove 104. Shown at 122 
in FIG. 8 is the hood of the vehicle. The headlight body 4 has an air hole 
129 for allowing the interior and exterior of the headlight to communicate 
with each other to prevent the lenses from collecting moisture thereon due 
to the temperature difference, as shown in FIG. 6, and further has 
communication holes 130 and 131 for the same purpose, as shown in FIGS. 8 
and 11. To attach the headlight body 4 to the body of the vehicle, a clamp 
is secured to the headlight body by screws, and the vehicle body is 
provided with a jut, which is engaged with the clamp. To reinforce the 
attachment, attaching arms 24 are integrally formed on the central portion 
of the headlight body 4 so as to project backward from the portion in the 
front-to-rear direction of the vehicle, and clamped with spring nuts 126 
and fasteners 127 at the tips of the arms to brackets 128 on the vehicle 
body by bolts, as shown in FIGS. 4, 15 and 17. 
In a vehicular headlight constructed in accordance with the present 
invention, an inner lens and a hood, which is painted to block light, are 
integrally made of a light-transmissible resin so that no opening is 
formed between the inner lens and the hood. As a result, no light can leak 
through such an opening, and no adjustment gap between the inner lens and 
reflector is seen through the opening. Since the inner lens and the hood, 
which would be separately provided in a conventional headlight, are 
constituted by a single component, the number of components of the 
headlight is reduced to decrease the number of steps of assembly thereof.