CN107110474B

CN107110474B - Multi-module motor vehicle headlamp with single motor actuated movable reflector

Info

Publication number: CN107110474B
Application number: CN201580058080.9A
Authority: CN
Inventors: 哈桑·寇劳; 西里尔·瑞维尔; A·奥布里
Original assignee: AML Systems SAS
Current assignee: AML Systems SAS
Priority date: 2014-10-30
Filing date: 2015-10-22
Publication date: 2021-10-12
Anticipated expiration: 2035-10-22
Also published as: CN107110474A; EP3212995A1; WO2016066928A1; EP3212995B1; FR3028003A1; FR3028003B1

Abstract

The invention relates to a multi-module motor vehicle headlamp comprising a movable reflector actuated by a single motor. The headlight (11) is of the multi-module type and each module (11a, 11b) constituting said headlight (11) comprises at least one light source and at least one movable member for blocking a light beam (4a, 4b) which, depending on its position, is able to block or allow the passage of a portion of the light beam coming from the light source, the blocking members (4a, 4b) of at least two modules being actuated by a common moving means, the reflecting surfaces of the two modules being flat reflectors (4a, 4b), said flat reflectors (4a, 4b) being mounted on a common axis (5) and being able to rotate about said common axis (5), which is oriented perpendicularly to the optical axis.

Description

Multi-module motor vehicle headlamp with single motor actuated movable reflector

Technical Field

The field of the invention is that of devices for motor vehicles, more particularly headlights for these motor vehicles.

Background

Headlights for motor vehicles generally comprise a reflecting portion, inside which there are a light source and means of controlling the shape of the light beam emitted by said light source to adapt it to the driving environment.

The reflector is typically in the form of a body of revolution of a paraboloid or ellipsoid for which the light source is positioned at the focal point of these surfaces or at one of the focal points of these surfaces. In the case of an ellipsoid (ellipsoid), conventionally, the light source is positioned at a first focal point and the lens is positioned on the optical axis such that the focal point of the lens itself coincides with a second focal point of the ellipsoid. In order to reduce the size of the headlight, it is envisaged that the vertical extension of the headlight may be reduced and only half of the ellipsoid remains to form the reflector. In some configurations, a mirror is then positioned at the second focal point such that light incident on the mirror is returned upwardly.

Furthermore, it is known that a blocking strip can be used to enable the various stages of blocking the light beam. When controlled, the strip is electrically actuated to move between at least two angular positions where it more or less blocks the light beam. This makes it possible to limit the range of the headlights, for example, to a low beam position, to avoid dazzling drivers driving in opposite directions, or to a main beam, at which no interruption occurs. This technique is currently used with headlights comprising high-power light sources, such as headlights with halogen or xenon lamps, for which the loss of optical power caused by being blocked off by the strip does not cause problems.

In addition, the technology of motor vehicle headlamps is currently moving towards light sources consisting of light-emitting diodes (LEDs) due to their low cost and long life. On the other hand, the optical power emitted by these devices is still limited at present and these devices must be optimally utilized. It is therefore desirable to be able to cope without blocking flaps which absorb about half the emitted light flux at the low beam position. To meet this requirement, in the case of an ellipsoid, it is conceivable to make the beam-deflecting mirror freely movable between a low beam position, in which it deflects all the rays upwards towards the top of the flip lens, and a main beam position, in which it does not interfere with the rays and allows them to reach the bottom of the lens.

Finally, it may be necessary to use several headlights arranged parallel to each other to generate the required light beam, to obtain the required light power, or to give the light beam a particular shape, or to adjust the light intensity distribution of the light beam.

This variety of headlights, in relation to individually movable mirrors and mechanisms for controlling the movement of these mirrors, makes the manufacture of LED headlights rather complicated and it is desirable to make the manufacture of the headlights easier. It is therefore an object of the present invention to overcome these drawbacks by disclosing a simplified actuating device, in particular for a multi-lamp with a semi-ellipsoidal reflector.

Disclosure of Invention

To this end, the object of the invention is a multi-module headlamp for a motor vehicle, each module forming part of said headlamp, the headlamp comprising at least one light source and at least one movable beam blocking device capable of blocking or enabling passage of a part of the light beam output by said light source, depending on its position, characterized in that the blocking means of at least two modules are common or actuated by a common movement control means.

This common use reduces the number of components that have to control the switching from the main beam to the low beam and vice versa and simplifies the manufacture of the headlight.

In a particular embodiment, each module comprises a reflecting portion, the light source of the module being positioned at a point of the reflecting portion referred to as the first focal point, and the reflecting portion having a shape such that at least a portion of the light rays output from the light source converge, after reflection, towards a point of the reflecting portion referred to as the second focal point.

Advantageously, the reflective portions of the two modules are open part-ellipsoids or semi-ellipsoids extending above the symmetry plane of the ellipsoid. The focus of the reflection part is the focus of the ellipsoid.

Preferably, the two modules are arranged side by side with their optical axes parallel and the second focal points of the two modules have the same abscissa on the optical axes. This adjacency makes it easier to manufacture devices that control the switching from the main beam to the low beam and vice versa.

In a particular embodiment, the reflective portions of the two modules are semi-ellipsoids extending above the plane of symmetry of the ellipsoid, and the beam blocking devices in the two modules are reflective surfaces facing upwards with respect to the plane of symmetry of the ellipsoid. This configuration has the advantage of being more compact and easier to place in a motor vehicle.

Preferably, the reflecting surfaces of the two modules are planar mirrors which are arranged to approximately coincide (in-line) in the longitudinal direction with the second focal point of the reflecting portion of the planar mirrors, the modules further comprising a turning device for turning the beams thereof to redirect the luminous flux output from the second focal point into a direction parallel to the optical axis.

Advantageously, the turning device for at least one module is a lens, the longitudinal position of the focal point of which approximately coincides with the second focal point of the respective reflection.

Advantageously, the planar mirror is free to rotate about the same axis, which is oriented approximately perpendicular to the optical axis.

More advantageously, the rotation shaft comprises a toothed segment extending in a plane approximately perpendicular to the longitudinal direction of the rotation shaft.

Preferably, the rotating shaft is carried by a single motor engaged on said toothed sector portion.

More preferably, the motor outputs a torque opposing the rotation return spring. This arrangement ensures that the headlight remains in the low beam position if the actuator motor of the beam blocking means fails.

In another embodiment, said reflective surface is a complex surface capable of shaping a vehicle headlight beam directly from at least a portion of the beam output from said second focal point.

In a preferred embodiment, the light source for at least one module is a light emitting diode.

Drawings

The invention will be better understood and other objects, details, characteristics and advantages thereof will become more apparent from the following detailed description of embodiments of the invention, given purely for purposes of illustration and in a non-limiting manner with reference to the accompanying drawings.

In these drawings:

figure 1 is a schematic view of an oval headlamp of a motor vehicle,

figure 2 is a schematic view of a semi-elliptical headlamp with a movable reflector in the main beam position,

figure 3 is a view of the headlight in figure 2 in a low beam position,

figure 4 is a perspective view of a multi-module headlamp according to the invention with movable reflectors in the main beam position,

FIG. 5 is a view of the headlamp in FIG. 4 in a low beam position, an

Fig. 6 is a longitudinal sectional view of the headlamp in fig. 4.

Detailed Description

Fig. 1 shows a headlight 1 for a motor vehicle according to the prior art, which headlight consists of a reflector 2 and a converging lens 3, the reflector 2 having the shape of an approximately open partial ellipsoid, the light source S being located inside the reflector, the converging lens being arranged in front of the reflector. The light source S is arranged at the first focal point of the ellipsoid on the side of the reflector 2 and emits light in the entire solid angle formed by the ellipsoid. After reflection on the reflector 2, all emitted light rays are directed towards the second focal point F of the ellipsoid.

On the optical axis x-x of the headlight 1, the lens 3 is arranged longitudinally in a position such that the focal point of the lens is approximately at the second focal point F of the ellipsoid. So that the light from the reflecting portion 2 is straightened so that the light is approximately parallel to the optical axis when output from the lens 3. The result is thus obtained that, at the position of the main beam, the beam illuminates roads over long distances. A blocking mechanism (not shown) must then be provided to remove the lower part of the beam before it passes through the lens and to create the low beam position.

Fig. 2 and 3 show a semi-elliptical headlight with a movable reflector in a main beam position and a low beam position, respectively.

In this case, unlike in fig. 1, the reflector 12 comprises only the upper half of the partial ellipsoid of the former case. Thus, as shown in the figure, the light source emits light only over a solid angle of 2 π steradians, i.e. over a 180 sector facing upwards in the section in the perpendicular plane through the optical axis. This configuration is particularly suitable for light sources consisting of Light Emitting Diodes (LEDs) which emit light only over a solid angle equal to 2 pi steradians.

As described earlier, after being reflected on the reflection part 12, the light flux is guided toward the second focal point F of the ellipsoid, and then reaches the condenser lens 3. Due to this emission of light with 2 pi steradians, the light beam is directed only to the lower half of the lens 3. The shape of the lens and/or the position of the focal point of the lens relative to the second focal point F of the ellipsoid is such that, if there is no means to divert the beam, the beam will be redirected forward.

However, as can be seen in fig. 2 and 3, the movable mirror 4 is arranged at the second focal point F. The reflecting surface of the mirror faces upward so as to block the light flux from the reflecting portion 12. The mirror 4 is freely movable about a horizontal axis in order to place its reflecting surface in a horizontal plane through the optical axis x-x or in a plane inclined forwards from the horizontal plane in a so-called retracted position.

In fig. 2, the mirror 4 is inclined with respect to the horizontal and is positioned completely outside the light flux, thus enabling all the rays to pass towards the lens 3. These rays pass through the bottom portion of the lens and are directed upward to illuminate long distance roads. The resulting position is the main beam position without any loss of optical power emitted by the light source S.

On the other hand, in fig. 3, the mirror 4 is in a horizontal position and the longitudinal length of the mirror is sufficient to block all light from the reflecting portion 12. All these rays are reflected upwards by the mirror 4 and the mirror redirects these rays towards the top part of the lens 3. On exiting from the lens, the light is directed forward but with a downward bend to illuminate the road for a specified distance. The downward bending is obtained by giving the lens 3 a shape and/or by a shift of the focal point of the lens with respect to the second focal point of the ellipsoid. The resulting position is a low beam position, again without any loss of optical power emitted by the light source S.

Fig. 4 and 5 show the headlight 11 in a main beam configuration and a low beam configuration, respectively, consisting of two

semi-elliptical modules

11a and 11b juxtaposed next to each other with LEDs, the symmetry axes of which are parallel. A module of a headlamp means a light system in which all or some of the light rays output from a light source are turned by a reflecting surface toward a focal point called a focal point.

As shown in the drawing, each module includes a

reflection portion

12a and 12b, respectively, in which a light source (not shown) is disposed, and a

movable mirror

4a and 4b, respectively, which is rotatable about a horizontal axis transverse to the direction of the optical axis of the module. As described for the individual modules with reference to fig. 2 and 3, the light source is positioned at the first focus of each reflector and the movable mirror is positioned at the second focus of the same module. Thus, due to the rotation of each mirror, a beam can be generated in a main beam configuration (mirror down) or in a low beam configuration (mirror up).

For example, some benefits of multiple modules are that the multiple modules can provide higher optical power, result in a wider beam, or produce higher optical density in a portion of a beam, particularly at the center of the beam. It is important, however, that the two (or more) modules operate in common (symbology) and switch from the main beam to the low beam or vice versa at the same time.

It is recommended (recommend) by the invention that these synchronized actions should be ensured, for example, by mounting the movable mirrors on a common axis 5 oriented perpendicular to the optical axis. The shaft is driven in rotation by a motor 6 and returned to a rest position corresponding to the low beam position by return means, such as for example a torsion spring 7. As shown in the figures, the return spring 7 is mounted on the shaft 5 and is supported firstly on the structure of the headlight 11 and secondly on a stop supported by the shaft 5. The motor 6 is placed at one end of the shaft 5 (e.g. underneath one of the two modules as shown in fig. 4 or 5) and is fixed to the structure of the corresponding headlight module 11 a.

Figure 6 shows a front view of a section in the vertical symmetry plane of the ellipsoid of the first module 11a, details of the individual devices and the relative position of each device. Unlike the previous figures, in this case the position of the lens 3 (not shown) is realized by a support 8 of this lens, which is arranged on the output side of the second focus F of the reflector 12a on the optical axis x-x. The movable mirror 4a is shown in its retracted position, which corresponds to the main beam position, and which has free space above it, so that it can be moved into a position along the optical axis and thus occupy a position corresponding to a low beam.

The rotary shaft 5 on which the mirror 4a is supported rotates in a bearing supported by the structure of the headlight 11a and extends horizontally below the optical axis. The shape of the rotation axis is generally a cylindrical revolution body, however, each side of each of the

mirrors

4a and 4b supported by the rotation axis has a cut surface (finished) shape to which the supporting member 52 of the mirror is fixed. These tangential shapes are used to drive the mirror in rotation when the shaft 5 itself is driven in rotation by the motor 6.

As shown, the shaft 5 comprises behind the section, in other words between the two

modules

11a and 12b in the previous figures, a toothed sector 9 rigidly attached to the shaft and extending downwards in a vertical plane. The toothed segment portion is engaged with teeth (not shown) of a drive shaft output from the motor 6. Thus, rotation of the motor in one direction or the other will rotate the toothed sector portion of the drive shaft 5 and, thus, the mirror 4a, via the tangential shape of the shaft 5 and the bearing member 52. Rotation of the motor in a clockwise direction rotates the shaft 5 in a counter-clockwise direction compressing the return spring 7. This causes the mirror 4a to reach its retracted position corresponding to the main beam (as shown in figure 6). Conversely, rotation of the motor in the anticlockwise direction releases the pressure on the spring 7, so that the mirror can return to the horizontal position corresponding to the low beam.

As shown in fig. 4 and 5, there is a single toothed segment 9 and a rotating shaft 5 which are common to all the mirrors in the

modules

11a, 11b mounted in the headlight 11. Whereas in the prior art each headlamp module has its own actuator motor for its reflector, the present invention can use a minimum amount of equipment to enable all modules to be moved from one position (low beam or main beam) to another so that such switching can be done simultaneously in each module of the headlamp 11.

The axis 5 is thus shown in the form of a cylindrical body of revolution, with the modules being positioned side by side in line with the axis, but the invention can also be made using modules longitudinally or vertically offset with respect to each other, provided that there is a single device capable of driving the mirrors of the different modules.

The invention is described as having a combination of a planar mirror 4 and a lens 3 that reverses the light and imparts the desired shape to the beam. The invention can also be made with a single beam steering device, such as a complex shaped mirror, that steers the beam forward and imparts the desired shape to the beam. In this case, the transition from the main beam configuration to the low beam configuration is done by the displacement of the complex-shaped mirror, which is therefore movable as in the disclosed configuration, a planar mirror.

Similarly, the blocking means of the beams switching from the main beam to the low beam are described in the form of a movable mirror that can rotate freely about an axis transverse to the optical axis. The blocking means can also be made, entirely equivalently (equal well), in the form of a movable flap that can move freely in vertical translation, or by any other movable means, provided that it can occupy several positions in which it blocks and reflects part of the light beam, or allows the light beam to pass.

Finally, the headlight has the shape of a semi-ellipsoid, but the principle of a common means of actuating the beam-blocking devices in several modules is also applicable in the case of a complete ellipsoid.

Finally, the present invention has been explained using an example of a headlamp in the case of having a reflector (the reflector may be an ellipsoid or a semi-ellipsoid). The invention can be applied quite equally to headlights without reflector, the light emitted by a light source, such as for example LEDs, being directed directly onto a movable blocking device which switches the light beam from the main to the low and vice versa.

Claims

1. Multi-module headlamp for a motor vehicle, each module (11a, 11b) forming part of the multi-module headlamp (11), comprising at least one light source (S) and at least one movable beam blocking device (4a, 4b) capable of blocking a portion of the light beam output by the light source or allowing the light beam to pass, depending on its position, the beam blocking devices (4a, 4b) of at least two modules being driven by a common movement control means,

characterized in that each module (11a, 11b) comprises a reflecting portion (12a, 12b) and a converging lens (3), the light source (S) of the module being arranged at a point of the reflecting portion (12a, 12b) called first focus, and the reflecting portion (12a, 12b) having a shape such that at least a part of the light rays output from the light source converge after reflection towards a point of the reflecting portion called second focus (F), the two modules being arranged side by side with their optical axes parallel and the second focuses of the two modules having the same abscissa on the optical axis, one or more of the beam-blocking devices in the two modules having a reflecting surface facing upwards with respect to the plane of symmetry of the ellipsoid, the reflecting surfaces of the two modules being planar reflectors (4a, 4b) said planar mirrors (4a, 4b) being mounted on a common axis (5) and being freely rotatably movable about said common axis (5) oriented perpendicular to the optical axis, the light beams being able to be generated in a main beam configuration or in a low beam configuration as a result of the rotation of each of said planar mirrors, said modules operating jointly and simultaneously switching from a main beam to a low beam or vice versa,

wherein after reflection on the reflection parts (12a, 12b), the light flux is directed towards the second focal point (F) of the ellipsoid and then reaches the converging lens (3),

wherein, in a main beam position, the module, when the planar mirrors (4a, 4b) are tilted with respect to the horizontal plane and are positioned completely outside the light flux such that all light rays can pass towards the lens (3), pass through a bottom portion of the lens (3) and are directed upwards,

wherein, when the planar mirrors (4a, 4b) are in a horizontal position and the longitudinal extent of the planar mirrors is sufficient to block all light rays from the reflective portion (12), the module is in a low beam position, all of these light rays being reflected upwardly by the planar mirrors (4a, 4b) and the planar mirrors (4a, 4b) redirecting these light rays towards the top portion of the lens (3), upon exit from the lens (3), the light rays being directed forwardly but with a downward bend to illuminate the road at the specified distance.

2. A multi-module headlight according to claim 1, wherein the reflective parts (12a, 12b) of the two modules are open partial ellipsoids or semi-ellipsoids extending above a symmetry plane of the ellipsoids.

3. A multi-module headlamp according to claim 1, wherein the reflective surfaces of the two modules are planar mirrors (4a, 4b) arranged to approximately coincide in the longitudinal direction with the second focal points of their reflective portions (12a, 12b), the modules further comprising a flipping device for flipping the light beams of the modules to redirect the luminous flux output from the second focal points into a direction parallel to the optical axis.

4. A multi-module headlight according to claim 3, wherein the turning device for at least one module is a lens (3) having a longitudinal position of its focal point approximately coinciding with the second focal point of the corresponding reflector.

5. A multi-module headlight as claimed in claim 1, wherein the shaft (5) comprises a tangential shape on each side of each of the planar mirrors (4a, 4b) supported thereby, wherein a support member (52) of the planar mirror is fixed to the tangential shape.

6. A multi-module headlight as claimed in claim 1 or 2, wherein the common shaft (5) comprises toothed segments (9) extending in a plane approximately perpendicular to the longitudinal direction of the common shaft.

7. A multi-module headlamp according to claim 6, wherein the common shaft is carried by a single motor (6) engaged on the toothed segment portion (9).

8. A multi-module headlamp according to claim 7, wherein the motor (6) outputs a torque opposing a rotary return spring (7).

9. A multi-module headlamp according to claim 8, wherein the reflective surface is a complex surface that enables shaping of an automotive headlamp beam directly from at least a portion of the beam output from the second focal point.

10. A multi-module headlamp according to claim 1 or 2, wherein the light source (S) of at least one module is a light emitting diode.