Headlight for vehicles with reflector adjusting device

The headlight has a reflector mounted inside a casing and swivelable about an axis by an adjustment element rotatably mounted in the casing. The adjustment element has a portion formed eccentrically to its axis of rotation. In the casing a transmission element is mounted for swiveling about an axis and is swivelably connected to the reflector. The transmission element has a recess in which the eccentric portion of the adjustment element is received, so that the transmission element is coupled, in the tangential direction relative to the axis about which it is swivelable in the casing, to the eccentric portion. On rotation of the adjustment element the reflector is swiveled about the swivel axis and the magnitude of the swiveling movement of the reflector is determined by the magnitude of the eccentricity of the portion and the lever ratios of the transmission element.

BACKGROUND OF THE INVENTION 
The present invention relates to a headlight for vehicles. 
A headlight known from DE 35 15 150 A1 has a holder and a reflector which 
is at least indirectly mounted on the holder and is swivelable relative to 
the holder about at least one axis by means of and adjustment device. This 
holder is in the form of a frame and an adjustment element of the 
adjustment device is rotatably mounted on said frame. The adjustment 
element is in the form of an adjusting screw which by means of a nut 
element is pivoted at least indirectly on the reflector eccentrically to 
the swivel axis of the reflector. The adjusting screw extends 
approximately parallel to the optical axis of the reflector and on the 
rear side of the holder projects through the latter. The space available 
for installing the headlight on the vehicle is often restricted, 
particularly on the rear side of the holder, facing the engine compartment 
of the vehicle, so that in certain circumstances it is not possible to 
provide sufficient space on the rear side of the headlight for the 
actuation of the adjustment element. The swiveling movement of the 
reflector must be limited in both swiveling directions by a respective 
stop, in order to prevent detachment of the connection of the adjustment 
element to the nut element. Particularly in the case of automated 
adjustment of the reflector, there is then a risk that component parts of 
the headlight will be damaged on striking against the stop. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a 
headlight for vehicles which avoids the disadvantages of the prior art. 
In keeping with these objects and with others which will become apparent 
hereinafter, one feature of the present invention resides, briefly stated, 
in a headlight which has a holder and a reflector at least indirectly 
mounted on the holder and swivelable relative to the holder about at least 
one swivel axis by an adjusting device, the adjusting device has an 
adjusting element rotatably mounted on the holder and provided with a 
portion which is formed eccentrically relative to the swivel axis, and 
also the adjusting device has a transmission element mounted on the holder 
for swiveling about an additional axis, the transmission element is at 
least indirectly swivelably connected to the reflector eccentrically to 
the additional axis and is coupled, eccentrically to the additional axis, 
to the eccentric portion of the adjustment element in the tangential 
direction relative to the additional axis. 
When the headlight for a vehicle is designed in accordance with the present 
invention, it has in contrast the advantage that the installed position of 
the adjustment element can be selected in coordination with the 
arrangement in each individual case of the swivel axis of the reflector in 
dependence on the installation conditions of the headlight. The adjustment 
device of the invention is in addition distinguished by compact 
construction. 
In accordance with a further feature of the present invention the 
adjustment element is rotatable about its axis of rotation through an 
angle 360 degrees relative to the holder. With the rotatability of the 
adjustment element through an angle of 360 degrees, a stop is not required 
in any direction for the limitation of the swiveling movement of the 
reflector, so that the above described difficulties in the adjustment of 
the reflector are avoided. In accordance with another feature of the 
present invention the adjustment element serves at the same time as a 
bearing element for the reflector, and the axis of rotation of the 
adjustment element extends at least approximately coaxially to the swivel 
axis of the reflector. With this design a simple construction of the 
headlight is made possible, because the adjustment element makes an 
additional bearing element unnecessary. The adjustment element can have a 
portion which is arranged outside the holder and is provided with 
toothing, wherein outside the holder there is arranged, as another part of 
the adjustment device, an actuating element which is in engagement with 
the toothing of the portion of the adjustment element and together with 
the portion provided with the toothing the actuating element forms a 
reduction gear. This construction permits additional stepping-down of the 
adjustment movement of the reflector, so that the latter is capable of 
sensitive adjustment. The arrangement of the actuating element on the 
holder can here be selected in dependence on the installation conditions 
of the headlight. 
Still another feature of the present invention is that the holder is formed 
as a casing, and the reflector is arranged inside the casing. Thereby the 
gap existing between the reflector and the holder part can be kept small. 
The novel features which are considered as characteristic for the invention 
are set forth in particular in the appended claims. The invention itself, 
however, both as to its construction and its method of operation, together 
with additional objects and advantages thereof, will be best understood 
from the following description of specific embodiments when read in 
connection with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A headlight for vehicles, particularly motor vehicles, which is illustrated 
in FIGS. 1 to 5, has a reflector 10 into which a light source 12 is 
inserted. The light source 12 used may be an incandescent lamp or a gas 
discharge lamp. The reflector 10 is made of sheet metal, but may also be 
made of any other suitable materials, for example of plastic. In order to 
screen light emitted directly by the light source 12 in the light emission 
direction 14, a screening cap 16 is provided which partly surrounds the 
light source 12 and which, as shown in FIG. 2, is fastened by means of a 
bracket 18 to a top wall 20 of the reflector 10. The reflector 10 is 
adjustably mounted on a holder in the form of a casing 22. On its rear 
side, pointing oppositely to the light emission direction 14, the casing 
22 has an opening which can be closed by means of a cap 24 and through 
which the light source 12 is accessible for replacement purposes. The 
light emission opening of the casing 22 is closed by a transparent cover 
disc 26, which may have a smooth surface or be provided with optically 
active elements. The cover disk 26 has a circumferential rim 28 pointing 
towards the casing 22 and received in a circumferential groove 30 which is 
open in the light emission direction 14 and which is formed in a flange 32 
projecting outwards from the casing 22. The casing 22 has a portion 34 
which is arranged inside the circumferential rim 28 of the cover disk 26 
and which projects beyond the flange 32 in the light emission direction 14 
and has a shape tapering oppositely to the light emission direction 14. 
The portion 34 may also be in the form of a separate part connected to the 
casing 22. The portion 34 may have a conical or curved shape, and its end 
pointing oppositely to the light emission direction 14 has a free 
cross-section corresponding approximately to the internal area of the 
reflector 10 at its front edge 36, which points in the light emission 
direction 14, so that light reflected by the reflector 10 can pass out 
unhindered through the portion 34. 
The reflector 10 is arranged inside the casing 22 and is mounted therein 
for swiveling about an axis 38 extending approximately horizontally. 
Swivelability of the reflector 10 about a horizontal axis is necessary, 
for example in order to permit adjustment of the inclination of the 
reflector, as prescribed by law, for fog lights for motor vehicles. The 
axis 38 extends approximately in the horizontal longitudinal center plane 
of the reflector 10 at right angles to the optical axis 39 of the 
reflector 10 and close to the apex region of the latter. A holding element 
40, which is in the form of a holding frame and is arranged in the region 
of the apex of the reflector 10, is rigidly connected to the latter. As 
illustrated in FIG. 1, the holding frame 40 comprises a main region 42 
which is connected to the reflector 10 and is substantially planar and 
which extends approximately at right angles to the optical axis 39, and 
also comprises lateral bearing regions 46 extending approximately parallel 
to the optical axis 39 of the reflector 10 and pointing in the light 
emission direction 14. Each of the bearing regions 46 has an opening 48, 
in which are engaged the ends of bearing elements which by their other 
ends are mounted in walls of the casing 22. A bearing element 50, shown on 
the left in FIG. 1, is in the form of a pin, which is mounted in a seat 52 
in a side wall of the casing 22. The pin 50 is pressed into the opening 48 
and is swivelably mounted in the seat 52. In the opening 48 of the other 
bearing region 46, on the right in FIG. 1, is engaged an adjustment 
element 54 which is rotatably mounted in a cylindrical seat 56 in the side 
wall of the casing 22 opposite the seat 52 and is part of an adjustment 
device by which the reflector 10 can be swiveled about the axis 38. By 
means of the bearing element 50 and the adjustment element 54 the holding 
frame 40, together with the reflector 10, is mounted for swiveling about 
the axis 38 formed by said elements. 
The adjustment element 54 has at its front end a pin-like portion 58 
pressed into the opening 48 of the bearing region 46, while its other end 
60 projects out of the casing 22. In the seat 56 the adjustment element 54 
has a portion 62 which in its outer contour is at least in part 
circular-cylindrical and which is provided with an annular groove 64, 
between which and the seat 56 a sealing ring 66 is clamped. The pin-like 
portion 58 and that portion 62 of the adjustment element 54 which is 
mounted in the seat 56 are arranged coaxially to one another and define 
the swivel axis 38. The bearing region 46 is arranged at a distance from 
the inner side of that side wall of the casing 22 in which the seat 56 is 
formed. Between the seat 56 and the bearing region 46 the adjustment 
element 54 has a portion 68 which is eccentric to the axis 38. As shown in 
FIG. 3, the portion 68 has at least approximately a circular shape in 
section perpendicular to the axis 38 and has a diameter such that the 
adjustment element 54 can be inserted into the seat 56 from outside the 
casing 22. 
As another part of the adjustment device there is arranged in the casing 22 
a transmission element 70 which in the exemplary embodiment is two-armed 
and, in the installed position of the headlight, is arranged with its 
longitudinal direction approximately vertical. As shown in FIG. 3, the 
transmission element 70 is mounted in a seat 75 in the casing 22 for 
swiveling about an axis 74 extending eccentrically to the swivel axis 38 
of the reflector 10, the axis 74 extending at least approximately parallel 
to the swivel axis 38 of the reflector 10. In the exemplary embodiment the 
axis 74 is arranged in the bottom end region 72 of the transmission 
element 70. The transmission element 70 is in addition mounted on the 
holding frame 40, eccentrically to the swivel axis 38 of the reflector 10, 
for swiveling about an axis 78, the axis 78 extending at least 
approximately parallel to the swivel axis 38. In the exemplary embodiment 
the transmission element 70 is swivelably mounted in its top end region 76 
in a bearing region 46 of the holding frame 40. The swivelable connection 
of the top end region 76 of the transmission element 70 to the bearing 
region 46 is made by means of a pin 77 which is arranged on said element 
and which engages in an opening which is provided in a top region of the 
holding frame 40 and is arranged approximately vertically above the 
opening 48, in which the pin-like portion 58 of the adjustment element 54 
engages. The transmission element 70 has a recess 80, in which the 
eccentric portion 68 of the adjustment element 54 is arranged. In the 
exemplary embodiment the recess 80 is arranged between the end regions 72 
and 76 of the transmission element 70. The recess 80 is in the form of an 
elongated hole which in the radial direction, relative to the axis 74 
about which the bottom end region 72 of the transmission element 70 is 
mounted for swiveling, has a greater extent than in the tangential 
direction relative to the axis 74. The width of the recess 80 in the 
tangential direction, relative to the axis 74, is dimensioned such that 
the eccentric portion 68 of the adjustment element 54 is rotatably 
received with slight play in the recess 80 and, in the radial direction 
relative to the axis 74, is translationally movable in the recess 80. The 
transmission element 70 is thus coupled, to the eccentric portion 68 of 
the adjustment element 54 in the tangential direction relative to the axis 
74. 
The transmission element 70 is made of plastic and, as illustrated in FIG. 
1, there is integrally formed on it at least one locking arm 82 which is 
resiliently deflectable transversely to the swivel axis 38 and which 
engages in a circumferential depression 84 in the adjustment element 54, 
in the direction of the casing 22, next to the eccentric portion 68 of 
said element, thereby securing the adjustment element 54 against being 
pulled out of the casing 22 along the swivel axis 38. In the exemplary 
embodiment two locking arms 82 are provided, being arranged opposite one 
another in relation to the swivel axis 38. As illustrated in FIG. 4, the 
side walls of the casing 22 are given an oval shape, viewed in section at 
right angles to the optical axis 39, with their curvature pointing 
outwards, and in section at right angles to the optical axis 39 of the 
curvature of the casing side wall arranged next to the transmission 
element 70, the transmission element 70 is approximately u-shaped, the end 
regions 72 and 74 of the latter being arranged as limbs extending away 
from the side wall towards the reflector 10. 
That portion 60 of the adjustment element 54 which is arranged outside the 
casing 22 is provided over its periphery with worm toothing and, as shown 
in FIG. 1, a flange 86 having a larger diameter is formed at its end. That 
portion 60 of the adjustment element 54 which is arranged outside the 
casing 22 has a larger diameter than the portion 62 arranged in the seat 
56, so that between these two portions 60 and 62 a step is provided which 
forms a stop limiting the movement pushing the adjustment element 54 into 
the casing 22. As illustrated in FIG. 5, outside the casing 22 there is 
arranged, as another part of the adjustment device and as actuating 
element for the adjustment element 54, an adjusting screw 88 having a 
portion 90 which is provided with a worm or a screw thread and which is in 
engagement with the worm toothing of the portion 60 of the adjustment 
element 54. The adjusting screw 88 is arranged at right angles to the 
swivel axis 38 and therefore to the longitudinal axis of the adjustment 
element 54, and at its end opposite the worm portion 90 has a head 92, 
which for example is provided with a hexagon and/or a cross slot for the 
application of a tool. The adjusting screw 88 is mounted on a bracket 94, 
which projects from the outer side of a side wall of the casing 22, for 
rotation about its longitudinal axis 89 but remains immovable in the 
direction of its longitudinal axis 89. In the exemplary embodiment 
illustrated, in the installed position of the headlight the adjusting 
screw 88 is arranged approximately vertically, with is head 94 pointing 
downwards. However, the adjusting screw 88 can also be arranged in any 
other positions at right angles to the swivel axis 38, around the portion 
60 provided with the worm toothing. The arrangement of the adjusting screw 
88 can be selected in a manner advantageous for the particular 
installation conditions of the headlight. The worm toothing of the portion 
60 and the adjusting screw 88 form a reduction gear unit, that is to say 
for a particular angle of rotation of the adjusting screw 88 about its 
longitudinal axis 89 the adjustment element 54 is turned only through a 
smaller angle of rotation about the swivel axis 38. 
The front edge 36, pointing in the light emission direction 14, of the 
reflector 10 is given a curved shape in planes at right angles to the 
swivel axis 38, the center point of its curvature being situated at least 
approximately on the swivel axis 38. That edge 96 of the portion 34 of the 
casing 22 which points oppositely to the light emission direction 14 
likewise has a curved shape in planes at right angles to the swivel axis 
38, the center point of its curvature being situated at least 
approximately on the swivel axis 38. The curvatures of the front edge 36 
of the reflector 10 and of the edge 96 of the portion 34 are at least 
approximately parallel to one another. Between the front edge 36 of the 
reflector 10 and the edge 96 of the portion 34 a gap 98 is provided, the 
curvatures of the front edge 36 of the reflector 10 and of the edge 96 of 
the portion 34 being so designed that when the reflector 10 makes a 
swiveling movement about the swivel axis 38 the gap 98 remains at least 
approximately constant. The front edge 36 of the reflector 10 and the edge 
96 of the portion 34 are preferably shaped at least approximately as 
circular arcs in sections at right angles to the swivel axis 38, their 
center points being arranged at least approximately on the swivel axis 38. 
In this arrangement the edge 96 has a radius exceeding by the size of the 
gap 98 the radius of the front edge 36. Depending on the size of the gap 
98, a certain variation of the curvatures of the edge 96 and of the front 
edge 36 is possible. 
The mode of operation of the adjustment device of the headlight described 
above is explained below. For the adjustment of the reflector 10 the 
adjusting screw 88 is turned and, by means of its worm portion 90 engaging 
in the worm toothing of the portion 60, in turn brings about a rotation of 
the adjustment element 54 about the swivel axis 38. On rotation of the 
adjustment element 54, the eccentric portion 68 of the latter is likewise 
turned but, because of its eccentric design relative to the swivel axis 
38, also makes a movement at right angles to the swivel axis 38 and 
tangentially to the axis 74 about which the transmission element 70 is 
swivelable. The tangential component of the movement of the eccentric 
portion 68 is transmitted to the transmission element 70, in the recess 80 
of which the portion 68 is received with slight play in the tangential 
direction and is thus coupled thereto. The transmission element 70 is 
thereby swiveled about the axis 74 at its bottom end region 72 mounted in 
the casing 22. The top end 76 of the transmission element 70 thus makes a 
swiveling movement about the axis 74, this movement being transmitted to 
the holding frame 40 through the connection of said element to the latter. 
The holding frame 40 and the reflector 10 connected to it are mounted by 
means of the bearing element 50 and the adjustment element 54, and thus 
make a swiveling movement about the swivel axis 38, so that the path of 
the optical axis 39 of the reflector 10 is varied in the vertical 
direction. The inclination of the optical axis 39 of the reflector 10, and 
therefore that of the light beam reflected by the reflector 10, in the 
downward direction is at its maximum when the eccentric portion 68 is so 
arranged that its greatest eccentricity relative to the axis 74 is 
arranged to be directed tangentially in the light emission direction 14. 
In this position the top end 76 of the transmission element 70 is situated 
in the position in which it has been swiveled the farthest in the light 
emission direction 14. The inclination of the optical axis 39 of the 
reflector 10, and therefore that of the light beam reflected by the 
reflector 10, in the upward direction is at its maximum when the eccentric 
portion 68 is so arranged that its greatest eccentricity relative to the 
axis 74 is arranged to be directed tangentially oppositely to the light 
emission direction 14. In this position the top end 76 of the transmission 
element 70 is situated in the position in which it has been swiveled the 
farthest oppositely to the light emission direction 14. The swiveling 
movement of the reflector 10 about the swivel axis 38 is not limited by a 
stop in any direction, on the contrary the adjustment element 54 can be 
turned beyond its extreme positions described above, whereupon an 
adjustment of the reflector 10 is again possible. In the exemplary 
embodiment illustrated, the eccentric portion 68 of the adjustment element 
54 is so arranged inside the recess 80, in its central or zero position, 
that its greatest eccentricity relative to the swivel axis 38 is directed 
upwards or downwards. The adjustment element 54 can be turned through 360 
degrees about the swivel axis 38, that is to say beyond its above 
described positions in which its greatest eccentricity is directed in or 
oppositely to the light emission direction 14, so that its greatest 
eccentricity is directed upwards. An additional stop for limiting the 
swiveling movement of the reflector 10 is not necessary, on the contrary 
the above described extreme positions of the eccentric portion 68 of the 
adjustment element 54 determine end positions of the reflector 10, beyond 
which the reflector 10 is swiveled back in the other direction when the 
adjustment element 54 is turned further. An adjustment of the reflector 10 
is thus possible, by turning the adjustment element 54, from any angular 
position of said element. Starting from the adjusting screw 88 the 
swiveling movement of the reflector 10 about the swivel axis 38 is stepped 
down three times, namely firstly by the stepping-down between the worm 
portion 90 and the worm toothing of the portion 60, secondly by the 
eccentric portion 68 which is coupled to the transmission element 70, and 
thirdly by the lever ratios of the transmission element 70. The 
stepping-down between the eccentric portion 68 and the transmission 
element 70 is determined by the amount of the eccentricity of the portion 
68 relative to the swivel axis 38. The lever ratios of the transmission 
element 70 result from the distances of the ends 72 and 76 of said element 
from one another and from the point at which the eccentric portion 68 
acts. Because of the high step-down ratio the adjustment device described 
above is self-locking from the adjusting screw 88 to the reflector 10, so 
that forces acting on the reflector 10, for example as the result of 
vibrations during he running of the vehicle equipped with the headlight, 
cannot lead to displacement of the reflector 10. 
When the reflector 10 makes a swiveling movement about the swivel axis 38, 
the front edge 36 of the reflector 10 also makes a movement about the 
swivel axis 38. Because of the above described design of the front edge 36 
of the reflector 10 and of the edge 96 of the portion 34, the gap 98 
remains at least approximately constant even when the reflector 10 makes a 
swiveling movement, and can therefore be kept small. 
It will be understood that each of the elements described above, or two or 
more together, may also find a useful application in other types of 
constructions differing from the types described above. 
While the invention has been illustrated and described as embodied in a 
headlight for vehicles, it is not intended to be limited to the details 
shown, since various modifications and structural changes may be made 
without departing in any way from the spirit of the present invention. 
Without further analysis, the foregoing will so fully reveal the gist of 
the present invention that others can, by applying current knowledge, 
readily adapt it for various applications without omitting features that, 
from the standpoint of prior art, fairly constitute essential 
characteristics of the generic or specific aspects of this invention. 
What is claimed as new and desired to be protected by Letters Patent is set 
forth in the appended claims.