EP2693109A2 - Light module - Google Patents

Abstract

The light module (10) has a lens device (18) for forming desired light distribution, where the lens device is exactly positioned in a desired spatial position by a positioning device. The positioning device has a dowel pin and a ball socket, where the dowel pin is engaged and guided in the ball socket for positioning the lens device. A fastening device has a fastening projection, fastening recess and a fastening unit. The fastening projection is engaged in the fastening recess and is fixed with the fastening unit for fastening the lens device. The dowel pin is extended along a guide direction.

Description

The invention relates to a light module, as can be found in particular in motor vehicle headlamps use.

In the present context, a light module is understood to mean the actual light-emitting unit of a headlight which emits the desired emission light distribution. This should, depending on the field of application, have certain, usually legally prescribed, characteristic intensity profiles. With car headlights, for example, dimmed light distributions (dipped beam, fog light) are to be generated, which are characterized by a cut-off line. On the other hand, high-beam light distributions are to be generated. In this case, for example, so-called partial high-beam distributions are desired in which specific areas of the emission light distribution are darkened. The desired Abstrahllichtverteilung therefore usually have a certain Structure of light and dark areas (eg a light-dark border or a hidden area), which should be achieved as precisely and reproducibly as possible.

Various technical solutions are known for generating the aforementioned light beam distribution. The known light modules usually comprise a light source for emitting light, a primary optics for forming a desired intermediate light distribution from the light of the light source, and a secondary optics, which is adapted to project the intermediate light distribution generated by the primary optics as Abstrahllichtverteilung in the apron of the light module. In particular, light modules are known which have a lens device which is set up to form a desired light distribution.

In order for the emission light distribution generated with such light modules to have the desired properties, precise positioning of the optically functional components relative to one another is of crucial importance.

For example, the arrangement of the primary optics relative to the light source has an influence on the proportion of the light of the light source which is detected by the primary optics and therefore determines the efficiency of the light module.

The arrangement of the secondary optics relative to the primary optics and / or the light source has an influence on whether desired light-dark transitions are imaged with sufficient contrast.

Another problem is that lenses or other transparent optical elements are usually made of a refractive material. Such materials usually have dispersion properties, ie they show a dependence of the refractive index on the wavelength of the light. As a rule, a stronger refraction occurs for light in the blue wavelength spectrum than for light in the red wavelength spectrum. When using lenses in light modules, this can lead to the emission light distribution showing undesired color effects. The mentioned structures of the emission light distribution from light and dark areas (eg light-dark boundary of the low beam, hidden areas of the partial high beam) can show color edges or color fringes. This dispersion effect is particularly noticeable in the case of lens devices which serve for the projection or imaging of an intermediate light distribution (produced, for example, by a primary optics) as emission light distribution into the apron of the light module, ie in the case of a lens device acting as secondary optics. In order to keep the undesired color effects as low as possible, said lens device (eg secondary optics) should be aligned and fastened precisely in relation to other optically-functional devices (eg primary optics).

To achieve this, in the prior art, the lens device is usually held in a lens holder, which is fixed by screwing, jamming or reshaping of the lens holder in the light module. A problem then is that a loosening of the attachment can be problematic or that after loosening the attachment re-attachment only with lower position accuracy is possible (eg because threaded bushings or thread by repeated input and Unscrewing are extended).

Precise positioning and attachment is particularly problematic when plastic parts are to be used since they are softer than metals and e.g. in threads or threaded bushes deformations may occur. Nevertheless, the use of plastic parts is increasingly desirable because such components can be made comparatively easily and inexpensively (e.g., by injection molding). In addition, plastic parts can be designed as design parts, which is particularly desirable for visible from outside the light module lens devices and lens holder.

The invention has for its object to allow for a light module a precisely positionable and at the same time easily detachable attachment of the lens device relative to other optical components. This should be advantageous in particular for plastic parts.

This object is achieved by a light module according to claim 1. This is a light module, in particular for motor vehicle headlights, which is set up to emit light with an emission light distribution in a main emission direction of the light module. The light module has a lens device, for example a converging lens, for shaping a desired light distribution. This light distribution may be the final emission light distribution of the light module or an intermediate light distribution. The lens device is guided by means of a positioning device in a desired position on the light module with exact position and by means of a fastening device there attached. The guide is positionally accurate in that the spatial position of the lens device relative to other components of the light module with respect to all three spatial directions can be precisely determined. The fastening device serves to connect the lens device in the position predetermined by means of the positioning device with one or more remaining components of the light module.

In the case of the light module according to the invention, the positioning device has at least one dowel pin and an associated dowel socket, the dowel pin engaging in the dowel socket for positioning the lens device. The fastening device has at least one fastening projection formed differently from the locating pin, an associated fastening recess, which is formed differently from the locating bush, and an associated fastening means. In this case, the fastening projection engages in the fastening recess for fastening the lens device and is fixed with the fastening means.

The fastening projection is preferably also formed like a pin. Accordingly, the mounting recess may be formed in the manner of a socket.

The invention is based on the idea to achieve a functional separation between positioning and attachment. The positioning device is formed with high precision. In this case, the dowel pin engages in the adapter socket essentially without play. Dowel pin and socket have a highly accurate fit, preferably such that the parts are barely movable against each other by hand. With the fastening device, however, lower requirements can be made of the fit. It is crucial here that an attachment is possible, which is designed in particular detachable. Even if the fastening device loses by multiple loosening and re-attaching to fit (for example, by widening threads), the positional alignment is ensured by the positioning device.

The embodiment of the invention allows a custom-fit arrangement in particular even if essential components of the light module are formed of plastic. This is often desirable, as this makes the parts are particularly inexpensive to produce and can be designed as a design part. Preferably, parts of the lens device, for example a lens holder of the lens device, in particular fastening projection and / or fastening recess and / or the fastening means are formed from plastic. In this case, a plastic suitable for injection molding is preferably used, for example PMMA, polycarbonate, polyimides or the like. Even with such plastic parts, a multiple attachment and detachment of the lens device is possible with the solution according to the invention. Even if the fastening device loses precision due to deformation of the fitting parts (for example due to characteristic creep processes of plastic material under pressure in threads), an exact positioning by the positioning device is ensured.

As a rule, the light module comprises further components, as explained in the introduction to the known light modules. In particular, a light source for emitting light is provided, wherein the lens device is adapted to shape the light emitted by the light source directly or indirectly (ie via a further optical device) in a desired light distribution, for example, to focus or collimate. In particular, the light module may also have a primary optics for shaping a desired intermediate light distribution from the light of the light source. Then a secondary optics is usually provided, which is adapted to project the light distribution generated by the primary optics as Abstrahllichtverteilung in the apron of the light module or image. In this case, said lens device forms in particular the secondary optics.

The positioning device preferably serves exclusively to allow an axial adjustment of the lens device in the light module. For this purpose, the dowel pin preferably extends along a guide direction and is displaceable free of play along this guide direction in the dowel sleeve. This allows a precise adjustment of the distance of the lens device to other optically functional components of the light module. However, a lateral positioning inaccuracy is avoided. The guide is free of play insofar as that a desired fit quality is achieved, for example, the parts against each other without noticeable game are mobile, as is customary for gears or clutches. It is also conceivable a fit such that parts against each other by hand is just still displaced, as is customary for guides on machine tools or collars.

The guiding direction is preferably substantially chosen in parallel to the main emission of the light module, so that no lateral positioning inaccuracy is caused by axial displacement of the lens device.

Preferably, the dowel pin and the attachment projection are disposed on the lens device directly or indirectly (i.e., over another component, e.g., support). The passport bushing and the fastening recess can then be arranged on another section of the light module, for example on a light source device, a carrier element or a primary optics device with respect to which the lens device is to be positioned and fastened.

It is also conceivable, however, another division of the components of fastening device and positioning device. Thus, for example, the passport sleeve can be arranged on the lens device and the associated dowel pin on another component of the light module. Likewise, the fastening recess may be arranged on the lens device and the associated fastening projection on a remaining component of the light module. It is also conceivable that the lens device has the dowel pin and the mounting recess, whereas the socket and the fastening projection are provided on another component of the light module.

To increase the position accuracy, the passport socket may be formed as a sintered bushing. In particular, the passport is formed of a metallic sintered material. This sintered bushing may for example be cast in a plastic component.

The dowel pin may be formed as a rotated metal pin. Also, the position accuracy is improved because with metal parts more accurate fits can be achieved than with plastic parts. The rotated metal pin can be cast for example in a plastic part. For this purpose, this plastic part may, after a first manufacturing step, have a pin recess into which the metal pin is cast in a second production step.

The attachment projection is preferably formed as a pin extending along a connection direction. In particular, this pin has a fixing slot extending along the connecting direction, into which the associated fastening means can engage. The associated fastening means is designed in particular as a fixing screw, which can be screwed into the fixing slot of the pin. Preferably, the fixing screw is screwed in a direction perpendicular to the connecting direction in the fixing slot such that the pin-like fastening projection is fixed in the mounting recess. For this purpose, the fastening recess is designed in particular in the manner of a bush, in which the fastening projection is displaceable along said connecting direction, wherein the fastening recess has a screw hole running perpendicular to the connecting direction, through which the fixing screw can be screwed into the fixing slot. Since the fixing slot extends along the connecting direction, the fastening projection can be inserted into a desired depth in the mounting recess and secured by screwing the fixing screw. Especially the pin-like fastening projection is designed slotted so that the pin spreads by screwing the fixing screw into the fixing slot. As a result, a partially positive connection between the fastening projection and the fastening recess can be produced. This embodiment is particularly advantageous in the case of plastic components, since with such materials typical deformations due to creep processes in the material can occur under force loading.

For a further embodiment, the lens device has a lens holder, in which an optically active lens element (for example, collecting lens) is held. Components of the fastening device and the positioning device are preferably arranged on the lens holder. In particular, the dowel pin and / or the fastening projection is provided on the lens holder. Of course, can be arranged on the lens holder and the fitting bushing and / or the mounting recess.

The light module can also have a holding frame, via which the lens device is fixed in the light module. For this purpose, the portion of the lens holder facing away from the lens element has a connecting portion, which can be joined together with a corresponding connecting portion of the holding frame. At the connecting portions of the holding frame and lens holder dowel pin, fitting bushing or mounting projection, mounting recess are arranged.

Preferably, guide pin and fastening projection extend parallel to each other. insofar The said guide direction and said connection direction are substantially parallel. As a result, an axial adjustment and positionally accurate axial attachment of the lens device is made possible.

According to a further aspect of the invention, the dowel pin engages without fastening in the mating socket. Then positioning device and fastening device are functionally completely separated from each other. The positioning function is not impaired by multiple attachment and detachment of the fastening device.

Further details and advantageous embodiments of the invention will become apparent from the following description, with reference to which the embodiment of the invention shown in the figure is described and explained in more detail.

Figur 1

perspektivische Darstellung von Baueinheiten zum Aufbau eines erfindungsgemäßen Lichtmoduls;

Figur 2

Detailansicht zu Figur 1, welche die Sekundäroptikeinheit mit Linseneinrichtung zeigt;

Figur 3

Detailansicht zu Figur 1, welche den Halterahmen zeigt, an dem die Linseneinrichtung angeordnet wird;

Figur 4

das Lichtmodul gemäß Figur 1 im endmontierten Zustand in Seitenansicht;

Figur 5

Schnitt A-A gemäß Figur 4 in Detailansicht;

Figur 6

Schnitt B-B gemäß Figur 4 in Detailansicht.

Show it:

FIG. 1

perspective view of structural units for constructing a light module according to the invention;

FIG. 2

Detail view too FIG. 1 showing the secondary optical unit with lens device;

FIG. 3

Detail view too FIG. 1 showing the holding frame on which the lens device is arranged;

FIG. 4

the light module according to FIG. 1 in final assembled state in side view;

FIG. 5

Section AA according to FIG. 4 in detail view;

FIG. 6

Section BB according to FIG. 4 in detail view.

In the following description, the same reference numerals are used for corresponding components and features.

FIG. 1 shows a modular light module 10, which is constructed from pre-assembled units. The main components of the light module 10 are: a light source unit 12, a primary optics unit 14, a support frame 16 and a secondary optics unit 18, which forms a lens unit in the present sense. These units are shown in the illustration FIG. 1 lined up along a mounting direction 20 and are moved towards the final assembly of the light module 10 substantially along the mounting direction 20 toward each other and joined together.

The light source unit 12 comprises a printed circuit board 22, which forms a front side of the light source unit 12 facing the primary optical unit 14. On the circuit board 22, a plurality of semiconductor light sources 26 are arrayed to emit light in the manner of a matrix. Furthermore, 22 electrical components of a control device are arranged on the printed circuit board, by means of which the individual semiconductor light sources are driven to the light output.

The primary optic unit 14 has a primary optic element 32 which has a primary optic exit surface 36. The primary optic element 32 also has a plurality of light entry surfaces (in FIG Fig. 1 not shown) through which light can be coupled into the primary optic element 32. The coupled light is in the primary optic element 32 bundled or collimated and exits through the primary optic exit surface 36 and forms there an intermediate light distribution.

The secondary optics unit 18 comprises a lens element 48 designed as a convergent lens. The latter is designed to project the intermediate light distribution on the primary optic exit surface 36 into the projection field of the light module 10 during operation of the light module 10. The secondary optics unit 18 therefore forms a lens device in the present sense. However, the idea according to the invention can also be used for the attachment of other lens devices of a light module, which do not form secondary optics.

The secondary optics unit 18 comprises a lens holder 50, which on the one hand serves to hold the lens element 48, on the other hand contributes to a positionally accurate alignment of the secondary optics unit 18. For this purpose, the region of the lens holder 50 facing away from the lens device 48 has a connecting section 52. The secondary optics unit 18 also has an ornamental element 54, which is designed like a frame and is arranged on the lens holder 50 in such a way that it surrounds the lens element 48 in the manner of a frame. The decorative element 54 is designed and arranged such that it is visible in the assembled state of the light module 10 when looking at the secondary optical unit 18 and thus determines the design. The decorative element 54 is at least partially visible when the light module 10 is installed in a headlight.

For mounting the light module 10, the holding frame 16 between the primary optical unit 14 on the one hand and the secondary optical unit 18 on the other. The holding frame 16 has a connecting portion 56 in its region facing the secondary optical unit 18. This can be assembled with the connecting portion 52 of the lens holder 50.

Essential components of the light module 10 are at least substantially made of plastic. This applies in particular to the lens holder 50, the decorative element 54 and the holding frame 16. These parts can be produced in an advantageous manner by injection molding. The lens device 48 or individual lenses of the lens device 48 are preferably made of plastic. Plastic lenses open up great design possibilities.

During the final assembly of the light module 10, the lens device 18 is connected to the holding frame 16 and thus to the remaining components of the light module 10. For this purpose, on the one hand a positioning device 60 is provided, which is set up to guide the lens device 18 in a desired spatial position with exact position. On the other hand, a fixing means 80 for fixing the lens means 18 in the desired position is provided.

The positioning device 60 and the fastening device 80 are first based on the Figures 2 and 3 explains which secondary optical unit 18 (FIG. Fig. 2 ) and the holding frame 16 ( Fig. 3 ) of the light module 10 in detail view.

The lens holder 50 has at its connecting portion 52 two dowel pins 62 (see FIG. 2 ). Each dowel 62 is formed as a rotated metal pin which is molded into the plastic material of the lens holder 50.

The holding frame 16 has at its connecting portion 56 two passport pins 62 associated with the mating sockets 64 (see FIG. 3 ). The mating sleeves 64 are formed as sintered sockets of a metallic sintered material and cast in the plastic material of the holding frame 16.

Each dowel pin 62 extends in a pin-like manner along a guide direction 66, along which the dowel pin 62 can be inserted into the respectively assigned dowel socket 64.

The positioning device 60 comprises the dowel pins 62 and the respectively associated mating sockets 64. These allow the lens device 18 to be guided into a desired spatial position relative to the remaining components of the light module 10.

In addition, a fastening device is provided in the light module 10, which serves to fix the lens device 18 in the position predetermined by the positioning device 60.

The fastening device 80 comprises on the one hand fastening projections 82 on the connecting section 52 of the lens holder 50.

Furthermore, the fastening device 80 on Holding frame 16 mounting recesses 84 which are assigned to the mounting projections 82 respectively. The attachment projections 82 and the attachment recesses 84 are formed in the plastic material of the lens holder 50 and the support frame 16, respectively. Preferably, the fastening projections 82 are integrally molded in the manufacture of the lens holder 50, for example by injection molding. The mounting recesses 84 may be integrally formed in the manufacture of the support frame 16 in this, for example by injection molding.

Each fastening projection 82 of the lens holder 50 extends in a pin-like manner along a connecting direction 86. For attachment, the fastening projection 82 engages in the respectively assigned fastening recess 84 along the connecting direction 86.

The FIG. 4 shows the light module 10 according to FIG. 1 in final assembled condition. In this case, the secondary optics unit 18 (lens device) is guided by means of the positioning device 60 into a desired position and fixed in this position by means of the fastening device 80.

To specify the exact position of the lens device 18, the dowel pin 62 engages in the associated female connector 64 without play. By moving the dowel pin 62 in the mating socket 64 along the guide direction 66, the axial distance of the lens device 18 to the support frame 16 can be adjusted precisely. A lateral positioning inaccuracy (ie perpendicular to the guide direction 66) is thereby avoided that for dowel pin 62 and mating socket 64 a backlash-free fit is selected. To clarify the shows FIG. 5 a detailed view of the positioning device 60 in a section through the in FIG. 4 with AA indicated cutting plane.

At the in FIG. 4 shown light module 10 in the final assembled state secondary optics unit 18 (lens device) is fixed by means of the fastening device 80 in the desired position, which will be explained below.

Each pin-like fastening projection 82 has a fixing slot 88 extending along the connecting direction 86 (see FIG FIG. 2 ). This makes it possible to insert the fastening projection 82 into a desired depth in the fastening recess 84 and to fix it there.

The FIG. 6 to illustrate the fastener 80 is a section along an in FIG. 4 with BB indicated level. The sectional plane runs perpendicular to the connecting direction 86.

In order to fix the fastening projection 82 in the desired insertion depth within the fastening recess 84, the fastening device comprises a fixing screw 90. This can be formed by a radial screw hole 92 (see also FIG FIG. 3 ) are screwed into the mounting recess 84. The Radialschraubloch 92 is arranged such that the fixing screw 90 can be screwed in the direction perpendicular to the connection direction 86. To fix the fastening projection 82 in the mounting recess 84, the fixing screw 90 is screwed through the radial screw hole 92, wherein the fixing screw 90 in the fixing slot 88 of pin-like fastening projection 82 engages (see FIG. 6 ). By screwing the fixing screw 90 into the fixing slot 88, the fastening projection 82 is spread open and thus fixed in the fastening recess 84.

In particular, when the fastening projection 82 and the fastening recess 84 are made of plastic, a positive connection between the fastening projection 82 and the fastening recess 84 can thus be achieved. Since the fixing slot 88 extends axially in the attachment projection 82 along the connection direction 86, the attachment projection 82 can be fixed in the attachment recess 84 at a desired insertion depth.

Claims (9)

Light module (10) for motor vehicle headlights, which is set up to emit light with a light beam distribution in a main emission direction, with a lens device (18) for shaping a desired light distribution, - With a positioning device (60) which is adapted to guide the lens device (18) in a desired spatial position accurately, - And with a fastening device (80) for fixing the lens device (18) in the desired position, characterized in that
the positioning device (60) has at least one dowel pin (62) and an associated dowel sleeve (64), wherein the dowel pin (62) for positioning the lens device (18) engages in and is guided in the dowel pin (64),
and in that the fastening device (80) has at least one fastening projection (82) formed differently from the locating pin (62), an associated fastening recess (84) and an associated fastening means (90), wherein the fastening projection (82) is fastened in the fastening recess (84) engages and is fixed with the fastening means (90). Light module (10) according to claim 1, characterized in that the dowel pin (62) extends along a guide direction (66) and along the guide direction (66) in the mating bushing (64) is slid backlash. Light module (10) according to one of the preceding claims, characterized in that the dowel pin (62) and the fastening projection (82) on the lens device (18) is arranged. Light module (10) according to one of the preceding claims, characterized in that the passport bushing (64) is designed as a sintered bushing. Light module (10) according to any one of the preceding claims, characterized in that the dowel pin (62) is designed as a rotated metal pin. Light module (10) according to any one of the preceding claims, characterized in that the fastening projection (82) as a along a connecting direction (86) extending pin is formed, which along the connecting direction (86) extending fixing slot (88), wherein the associated fastening means (90) is designed as a fixing screw, which is screwed in the direction perpendicular to the connecting direction (86) in the fixing slot (88) such that the fastening projection (82) in the mounting recess (84) is attached. Light module (10) according to one of the preceding claims, characterized in that the lens device (18) has a lens holder (50) in which an optical lens element (48) is held, wherein the dowel pin (62) and / or the fastening projection (82 ) is arranged on the lens holder (50). Light module (10) according to one of the preceding claims, characterized in that the guide pin (62) and the fastening projection (82) extend in parallel. Light module (10) according to one of the preceding claims, characterized in that the dowel pin (62) engages without fastening in the mating bushing (64).

Images