Patent Publication Number: US-2022228719-A1

Title: Lighting Device for Vehicle Headlamps

Description:
The invention relates to a lighting device for vehicle headlamps, comprising: 
     at least one light source, 
     a light guide comprising an end section with a light entry surface, wherein the light guide is assigned to the at least one light source for guiding light which is emitted by the at least one light source and coupled into the light guide at the light entry surface, 
     a light guide adapter configured to secure the end section of the light guide and to hold the light entry surface in a position with regard to the at least one light source, the light guide adapter comprises a base-section and a securing-section, and 
     a support frame, on which the light guide adapter is mounted. 
     Further, the invention relates to a vehicle headlamp comprising at least one lighting device according to the invention. 
     Further, the invention relates to a method for assembling of a lighting device. 
     In the state of the art, the light guide is secured in conventionally assemblies by screw connections or clamping with use of additional parts. This leads to a significant effort with regard to the securing of the light guide and centring in a desired position. 
     It is an object of the invention to provide an enhanced lighting device. 
     To achieve this object, the securing-section of the light guide adapter comprises at least one first engaging-element, the base-section comprises at least one first fastening-opening, 
     the support frame comprises a mounting-opening for the securing-section of the light guide adapter and a second fastening-opening, wherein the mounting-opening having at least one second engaging-element corresponding to the at least one first engaging-element of the securing-section, 
     wherein the light guide adapter can be brought into an end position by inserting the securing-section into the mounting-opening, such that the at least one first engaging-element engages with the at least one second engaging-element, wherein the at least one first fastening-opening of the light guide adapter and the at least one second fastening-opening of the support frame are overlapped, so that the first and second fastening-opening can receive a fastening-element. 
     As a result of this solution, a reliable locking and centring system for the light guide on the support frame of the lighting device is provided, which ensures an accurate positioning in relation to the support frame and thus the light source. 
     The light guide adapter on the one side protects the at least one light source from damage and also provides a defined distance between the at least one light source and the light entry surface of the light guide. 
     Advantageously, the at least one first engaging-element of the light guide adapter is built as first locking-element protruding transversely to a longitudinal axis of the securing-section, wherein the at least one second engaging-element of the mounting opening is built as a recess corresponding to the at least one first locking-element, 
     and wherein the light guide adapter can be brought into an intermediate position by inserting the securing-section into the mounting-opening, such that the at least one first locking-element passes through the at least one recess and the base-section abuts on a portion of the support frame, which surrounds the mounting-opening, 
     and wherein the light guide adapter can be brought into an end position by rotating the light guide adapter starting from the intermediate position around the longitudinal axis of the securing-section, such that the at least one first fastening-opening and the at least one second fastening-opening are overlapped, so that the first and second fastening-opening can receive a fastening-element. 
     Advantageously, the lighting device comprises a heat sink configured to dissipate the heat of the at least one light source, wherein the at least one light source is in thermal contact with the heat sink. 
     Advantageously, the heat sink comprises at least one fastening-element. 
     Advantageously, the at least one fastening-element is built as a pin protruding from the heat sink, which at least one pin is assigned to the at least one first and second fastening-opening, wherein the pin is insertable into the at least one first and second fastening-opening when the light guide adapter is in the end position. 
     Advantageously, the at least one first engaging-element is built as first latching-element, wherein the at least one second engaging-element is built as a counter latching-element. 
     Advantageously, the end section of the light guide comprises at least one second locking-element protruding transversely to a longitudinal axis of the end section, and wherein the end section is attachable to the securing-section of the light guide adapter and is lockable therein by means of the at least one second locking-element. 
     Advantageously, the securing-section of the light guide adapter comprises at least one recess with an abutment-portion corresponding to the at least one second locking-element of the end section of the light guide, wherein the at least one recess is configured to receive the at least one second locking-element, and wherein the end section is rotatable around the longitudinal axis or the light guide adapter is rotatable when the at least one second locking-element is received in the at least one recess of the securing section, such that the at least one second locking-element abuts on the abutment-portion of the at least one recess. 
     The abovementioned locking-mechanism or securing-mechanism can be a bayonet-locking mechanism. 
     Advantageously, the securing-section comprises two recesses with an abutment-portion, wherein the end section of the light guide comprises two corresponding second locking-elements. 
     Advantageously, the securing-section covers the end section of the light guide at least partly. 
     Advantageously, the inner surface of the securing-section, which surface covers the end section of the light guide, is metalized. 
     Thus, the effectivity in reflections at the end section of the light guide is increased. 
     At the same time, the insertion of the end section of the light guide into the securing-section of the light guide adapter leads to a shielding of the light feed externally. 
     The object of the invention is also be achieved by a method for assembling of a lighting device, comprising the following steps in chronological order: 
     a) providing 
     at least one light source, 
     a light guide comprising an end section with a light entry surface, wherein the light guide is assigned to the at least one light source for guiding light which is emitted by the at least one light source and coupled into the light guide at the light entry surface, 
     a light guide adapter configured to secure the end section of the light guide and to hold the light entry surface in a final target position with regard to a support frame, the light guide adapter comprises a base-section and a securing-section, wherein the securing-section of the light guide adapter comprises at least one first engaging-element, the base-section comprises at least one first fastening-opening, 
     a support frame, on which the light guide adapter is mounted, wherein the support frame comprises a mounting-opening for the securing-section and a second fastening-opening, wherein the mounting-opening having at least one second engaging-element corresponding to the at least one first engaging-element of the securing-section, 
     b) positioning the light guide in the final target position with regard to the support frame, 
     c) inserting the light guide adapter into the mounting-opening of the support frame, 
     d) bringing the light guide adapter into an end position, such that the at least one first engaging-element engages with the at least one second engaging-element, wherein the at least one first fastening-opening and the at least one second fastening-opening are overlapped, so that the first and second fastening-opening can receive a fastening-element, wherein the light guide adapter secure the end section of the light guide in the final target position, 
     e) inserting the fastening-element into the first and second fastening-opening. 
     Advantageously, the at least one first engaging-element is built as first locking-element protruding transversely to a longitudinal axis of the securing-section, wherein the at least one second engaging-element is built as a recess corresponding to the at least one first locking-element, 
     and wherein the light guide adapter can be brought into an intermediate position by inserting the securing-section into the mounting-opening of the support frame, such that the at least one first locking-element passes through the at least one recess and the base-section abuts on a portion of the support frame, which surrounds the mounting-opening, 
     and wherein the light guide adapter can be brought into an end position by rotating the light guide adapter starting from the intermediate position around the longitudinal axis of the securing-section, such that the at least one first fastening-opening and the at least one second fastening-opening are overlapped, so that the first and second fastening-opening can receive a fastening-element. 
     Advantageously, the end section of the light guide comprises at least one second locking-element protruding transversely to a longitudinal axis of the end section, and wherein the end section is attachable to the securing-section of the light guide adapter and is lockable by means of the at least one second locking-element, and wherein preferably the securing-section of the light guide adapter comprises at least one recess with an abutment-portion corresponding to the at least one second locking-element of the end section of the light guide, wherein the at least one recess of the securing section is configured to receive the at least one second locking-element of the light guide, and wherein the end section is rotatable around the longitudinal axis or the light guide adapter is rotatable, when the at least one second locking-element is received in the at least one recess, such that the at least one second locking-element abuts on the abutment-portion of the at least one recess. 
     Advantageously, in step d) the light guide adapter is rotated around the longitudinal axis of the securing-section, in order to bring the light guide adapter into the end position and to secure the end section of the light guide in the final target position with regard to the support frame. 
     This is particularly advantageous, if the light guide has a form or design, which does not allow a rotation, when the light guide adapter is in the desired final target position in a headlamp-housing or support frame, so that it is crucial to secure or fixate the end section of the light guide with regard to the support frame or the at least one light source with a light guide adapter. 
    
    
     
       In the following, in order to further demonstrate the present invention, illustrative and non-restrictive embodiments are discussed, as shown in the drawings, which show: 
         FIG. 1A  a side view of an example of a lighting device with light sources, a light guide secured in a light guide adapter, where the light guide adapter is inserted in a mounting opening of a support frame, 
         FIG. 1B  a perspective view of the lighting device of  FIG. 1A , 
         FIG. 2A  a detailed perspective view of the light guide adapter, 
         FIG. 2B  a detailed front view of the light guide adapter, 
         FIG. 3  a detailed view of the support frame and the mounting opening, 
         FIG. 4A  an intermediate position of the light guide adapter in the mounting opening of the support frame, and 
         FIG. 4B  an end position of the light guide adapter in the mounting opening of the support frame. 
     
    
    
       FIG. 1A  and  FIG. 1B  show a lighting device  10  for vehicle headlamps in a side view, wherein the lighting device  10  comprises light sources  50 , a light guide  200  having an end section  210  with a light entry surface, wherein the light guide  200  is assigned to the light sources  50  for guiding light which is emitted by the light sources  50  and coupled into the light guide  200  at the light entry surface. The lighting device  10  comprises a heat sink  100  configured to dissipate the heat of the light sources  50 , wherein the at least one light source  50  is in thermal contact with the heat sink  100 , wherein the heatsink  100  comprises a fastening-element  110 . 
     Further, the lighting device  10  comprises a light guide adapter  300  configured to secure the end section  210  of the light guide  200  and to hold the light entry surface in a position with regard to the at least one light source  50 , the light guide adapter  300  comprises a base-section  310  and a securing-section  320 , which can be seen in more detail in  FIG. 2A , and wherein the light guide adapter  300  is mounted on a support frame  400 . 
       FIG. 2A  and  FIG. 2B  show a more detailed view of the light guide adapter  300  itself, wherein the securing-section  320  of the light guide adapter  300  comprises two first engaging-elements  320   a,  which are built as first locking-elements protruding transversely to a longitudinal axis A of the securing-section  320 , the base-section  310  comprises one first fastening-opening  311 . 
       FIG. 3  shows a detailed view of the support frame  400 , wherein the support frame  400  comprises a mounting-opening  410  for the securing-section  320  and a second fastening-opening  411 , wherein the mounting-opening  410  having two second engaging-elements  410   a,  which are built as recesses corresponding to the two first locking-elements  320   a  of the securing-section  320 . 
     Referring to  FIG. 4A  (intermediate position P 1 ), the light guide adapter  300  can be brought into an intermediate position P 1  by inserting the securing-section  320  into the mounting-opening  410 , such that the two first locking-elements  320   a  passes through the two recesses  410   a  and the base-section  310  of the light guide adapter  300  abuts on a portion of the support frame  400 , which surrounds the mounting-opening  410 . 
     Referring to  FIG. 4B , the light guide adapter  300  can be brought into an end position P 2  by rotating the light guide adapter  300  starting from the intermediate position P 1  (shown in  FIG. 4A ) around the longitudinal axis A of the securing-section  320 , such that the first fastening-opening  311  of the light guide adapter  300  and the second fastening-opening  411  of the support frame  400  are overlapped, so that the first and second fastening-opening  311 ,  411  can receive the fastening-element  110  of the heatsink  100 , wherein the fastening-element  110  is built as a pin protruding from the heat sink  100 , the pin is assigned to the first and second fastening-opening  311 ,  411 , and wherein the pin is insertable into the first and second fastening-opening  311 ,  411  when the light guide adapter  300  is in the end position P 2 . 
     For securing the end section  210  of the light guide  200  in the securing-section  320  of the light guide adapter  300 , the end section  210  comprises two second locking-elements  211  protruding transversely to a longitudinal axis B of the end section  210 , and wherein the securing-section  320  comprises two recesses  330  with an abutment-portion  330   a  corresponding to the two second locking-elements  211  of the end section  210  of the light guide  200 . The two recesses  330  are configured to receive the two second locking-elements  211 , and wherein the end section  210  is rotatable around the longitudinal axis B when the two second locking-elements  211  are received in the recesses  330 , such that two second locking-elements  211  abut on the abutment-portions  330   a  of recesses  330 . The abovementioned locking-mechanism or securing-mechanism is substantially a bayonet-locking mechanism. 
     Further, the securing-section  320  covers the end section  210  of the light guide  200  at least partly, when the end section  210  is secured in the securing-section  320 , wherein the inner surface of the securing-section  320 , which surface covers the end section  210  of the light guide  200 , is metalized. 
     LIST OF REFERENCE SIGNS 
     Lighting device . . .  10   
     Light source . . .  50   
     Heat sink . . .  100   
     Fastening-element . . .  110   
     Light guide . . .  200   
     End section . . .  210   
     Second locking-element . . .  211   
     Light guide adapter . . .  300   
     Base-section . . .  310   
     First fastening-opening . . .  311   
     Securing-section . . .  320   
     First engaging-element . . .  320   a    
     Recess of the securing section . . .  330   
     Abutment-portion of the recess . . .  330   a    
     Support frame . . .  400   
     Mounting-opening . . .  410   
     Second engaging-element . . .  410   a    
     Second fastening-opening . . .  411   
     Intermediate position . . . P 1   
     End position . . . P 2   
     Longitudinal axis (adapter) . . . A 
     Longitudinal axis (end section) . . . B