DE102010000758A1 - Method for manufacturing LED module with multiple LEDs in e.g. automotive engineering taillight, involves cutting freely thin sheet arrangement of carrier film along one outer contour of thin sheet arrangement in order to obtain LED module - Google Patents

Abstract

The method involves providing multiple support plates (5) to a thin sheet arrangement (2) with a tree-like structured strip guard net (3). The thin sheet arrangement is applied on a flexible carrier film. The support plates of thin sheet arrangement are equipped with LEDs. An electrical interconnection is generated between the LEDs and the strip guard net. The thin sheet arrangement of the carrier film is freely cut along one outer contour of the thin sheet arrangement in order to obtain an LED module. Lugs are provided at the support plates, and recesses are brought into the lugs. An independent claim is also included for a LED module comprising a thin sheet arrangement with multiple support plates to receive LEDs and a strip guard net for power source of the LED.

Description

State of the art

The present invention relates to a method for producing an LED module with a plurality of LEDs and a corresponding LED module.

In lighting technology so-called LEDs are increasingly adopting a wider range of applications. For example, in vehicle technology taillights, turn signals or daytime running lights are increasingly provided by LEDs. In these applications, however, it may be necessary that the LED's, z. B. for design reasons, to be used in three-dimensional arrangements in the vehicle lights. So far, 3D LED modules for automotive taillights, turn signals or daytime running lights are mainly produced on the basis of relatively expensive flexible circuit boards, which are largely manually mounted in the spotlight after soldering. The object of the invention is the representation of a cost-effective, flexible production concept variants for the industrial production of various 3D LED modules.

Disclosure of the invention

The inventive method with the features of claim 1 has the advantage that it allows a cost-effective production of LED modules, the LED modules have a high flexibility to be used in different applications can. Here, a two-dimensional as well as a three-dimensional use of the LED module is easily possible. According to the invention, a cost-effective production, which is fully automated, can be achieved, wherein the LED modules can be used in particular for a variety of headlight geometries. This is inventively achieved in that the inventive method first provides a thin sheet assembly with a conductor track network and a plurality of carrier plates for receiving LED's. Subsequently, the thin sheet assembly is applied to a flexible carrier film, for. B. by gluing. The carrier film preferably has a one-sided adhesive surface. Thereafter, the carrier plates are fitted with LEDs and the LED's fixed on the carrier plates and electrically connected to the interconnect network. As a last step, the LED module is cut free from the carrier film along an outer contour of the thin sheet assembly. As a result, the LED module has the carrier foil only in the area of the thin-plate arrangement. The thus produced LED module has a flat, two-dimensional shape, but can be easily brought by bending in any three-dimensional shapes and thus easily adapted to predetermined three-dimensional structures of vehicle lights.

The dependent claims show preferred developments of the invention.

Retaining tabs are preferably provided on the carrier plates, which are produced from a carrier plate plane of the carrier plates by means of bending, preferably at an angle of 90 °. In the retaining tabs recesses are preferably provided which z. B. allow clipping the retaining tabs in support structures.

Particularly preferably, the LEDs are fixed on the carrier plate by means of soldering or welding or caulking and an electrical connection is established between the LEDs and the printed conductor network.

The thin sheet assembly is preferably made by stamping or lasering or etching a thin sheet.

For easy handling and to avoid damage, the LED module is preferably fixed on a 3D mold carrier. The 3D mold carrier has a rigid shape, so that handling of the LED module is facilitated.

To ensure the greatest possible flexibility of the LED module, the LED module has a tree-like structure with a stem area and a plurality of lateral branches. This allows a large number of LEDs are arranged in a small space.

Furthermore, the present invention relates to an LED module, which has the advantage that it is simple and inexpensive to produce and can be adapted in particular to different structures of lights, in particular motor vehicle lights. In this case, the LED module according to the invention comprises a thin-sheet arrangement with a plurality of carrier plates for receiving the LEDs and a printed conductor network. The thin-sheet arrangement is arranged on a flexible carrier foil, the carrier foil having a shape corresponding to an outer contour of the thin-plate arrangement. A plurality of LEDs is arranged on the carrier plates and electrically connected to the printed conductor network. By bending over parts of the interconnect network, the LED module according to the invention can be easily and inexpensively adapted to different two-dimensional or three-dimensional structures.

Preferably, the interconnect network of the LED module according to the invention has a tree-like Structure with a stem area and a plurality of lateral branches. This allows a high flexibility of the LED module to adapt to different structures can be achieved.

Further preferably, the lateral branches of the LED module according to the invention on one side of the stem area are each provided alternately with different lengths, in particular once shorter in each case and once longer in length.

Preferably, the conductor network connects the LEDs in series with each other. More preferably, the carrier plates are connected to the LED's such that the carrier plates can serve as cooling elements for the LED's. The carrier plates are also suitable as receiving geometries for the handling system during later conversion of the 2D structure into the 3D mold carriers, or as fixation geometry of the 2D structure during the placement and soldering process (2D = two-dimensional, 3D = three-dimensional).

The inventive method and the LED module according to the invention are particularly preferred in the automotive field, z. B. as a taillight, turn signals or daytime running lights used. The idea according to the invention makes it possible to significantly reduce the production costs, so that such LED modules can also be used in more cost-effective small cars.

drawing

Hereinafter, a preferred embodiment of the invention will be described in detail with reference to the accompanying drawings. In the drawing is:

1a - 1g schematic views to illustrate the manufacturing steps of the method according to the invention,

2 - 6 Top views of parts of the LED module according to the invention during the manufacturing steps,

7 a schematic representation of an assembly of the LED module on a base element,

8th a schematic side view of an alternative mounting of the LED module by caulking, and

9 a schematic view of an alternative manufacturing process.

Preferred embodiments of the invention

Hereinafter, with reference to the attached figures, a method according to the invention and an inventive LED module 1 described in detail.

The 1f schematically shows an inventive LED module 1 which is a thin sheet assembly 2 , a carrier film 8th and a variety of LEDs 9 includes. The thin sheet assembly 2 is in 1a represented and lies in a two-dimensional plane E and comprises a conductor network 3 with a tree-like structure. The conductor network 3 includes a stem area 3a and a variety of lateral branches 3b (S. 1a ). The side branches 3b branch alternately from a linear main direction of the stem area 3a from. Here are the side branches 3b alternating a short and a long length, starting from the trunk area 3a , on. At the end of each side turnoff 3b each is a carrier plate 5 arranged. The carrier plate 5 is a plate-like element which holds the LED's 9 serves. How out 1a it can be seen are on each carrier plate 5 three outwardly projecting retaining tabs 6 intended. The retaining tabs 6 can be bent over and serve to fix the carrier plate 5 on a base element 10 (S. 6 ). The basic element 10 each has small, slot-shaped recesses 10a for the retaining tabs 6 on. This is for example in 1g shown. In the retaining tabs 6 are recesses 7 designed to clip the retaining tabs into provided clip connections to the base member 10 to enable. As a result, a quick and easy installation is achieved. As in particular from 2 can be seen, the support plate 5 at a central area a recess 5a on. In the recess 5a is a prominent area 4 formed, which is centered in the recess 5a is arranged. Two lateral branches 3b of the interconnect network end up in the recess 5a without removing the carrier plate 5 to contact. Thus, in the thin sheet assembly 2 the conductor network 3 as well as the carrier plates 5 separate components. For contacting, the LED indicates 9 while on its underside three contact areas, including two contact areas for contact with the lateral branches 3b are provided and a central contact area for contact with the projecting area 4 is provided. The middle contact area serves to dissipate heat from the LED over the projecting area 4 on the carrier plate 5 ,

The inventive method for producing the LED module 1 runs as follows. In a first step ( 1a ) becomes a thin sheet assembly 2 , for example, by punching out a thin sheet metal material, with the interconnect network 3 and the carrier plates 5 together with the retaining tabs 6 provided. Likewise, the recesses become equal 7 in the retaining tabs 6 punched out. In a second step, this thin sheet arrangement 2 on the flexible carrier foil 8th applied. The carrier foil 8th is for example a plastic film and the thin sheet assembly 2 can z. B. by gluing or welding on the carrier film 8th be attached. This is in 1b shown. In a next step ( 1c ) become the carrier plates 5 with LEDs 9 stocked. Then those on the carrier plates 5 arranged LED's 9 z. B. by means of soldering with the lateral branches 3b electrically connected. Also, the average thermal contact of the LED's with the above range becomes 4 the carrier plate 5 connected. In a next step ( 1d ) are the retaining tabs 6 bent by 90 ° using a tool. This results in the area of the carrier plate 5 recesses 8a in the carrier film 8th , as the carrier film together with the retaining tabs 6 is bent over. If, however, the retaining tabs are already bent before loading and soldering the LED's, they can also be used as Fixiergeometriene on a workpiece carrier during the soldering process. Subsequently ( 1e ) becomes the remaining carrier film 8th removed so that the LED module is cut free, wherein the carrier film 8th along an outer contour of the thin sheet assembly 2 Will get removed. This is the carrier film 8th also in the middle of the stem area 3a away. The carrier foil 8th surrounds the entire outer contour of the thin sheet assembly 2 with a small width.

As in particular from 1e can be seen, the LED module points 1 a tree-like structure with the stem area 3a and a variety of lateral branches 3b on. The side branches 3b branch alternately to the left and right of the trunk area 3a in the longitudinal direction of the stem area 3a from. Here are the side branches 3b different lengths.

9 shows a particularly preferred variant of the manufacturing method according to the invention, in which a readily storable intermediate product of a carrier film having a plurality of thin-plate assemblies applied thereon 2 is possible. How out 9 is apparent, is the carrier film 8th formed so that it has a one-sided adhesive side 8c which, by means of a cover sheet 8b is covered. The material for the thin sheet assemblies 2 is on a roll 20 , z. B. an aluminum role provided. The carrier foil 8th as well as the thin sheet metal foil 20 are handled in what 9 indicated by the arrows A and B, and the peeled cover sheet of the carrier film 8th is rewound (arrow C). Then the carrier foil 8th and the thin sheet metal in the direction of arrow D is fed to a punching processing. At the punching is a punching tool with a punch 31 , a punching die 32 and an anvil 33 arranged. The carrier foil 8th and the thin sheet metal sheet are thereby fed so that the punching die 32 between the carrier film 8th and the thin sheet metal foil is arranged. The anvil 33 is below the punching die 32 arranged. The double arrow F indicates the movement of the punch 31 which has a positive layout structure corresponding to the shape of the thin sheet assembly 2 , having. During the punching process, the punched thin sheet assemblies become 2 at the same time also on the adhesive side of the carrier film 8th pressed so that these immediately after punching on the carrier foil 8th glue. After punching the carrier film and the thin sheet metal are moved by one clock and punched out the next thin sheet assembly and glued to the carrier film. Thus, a variety of thin sheet assemblies 2 on the adhesive film 8th arranged. The adhesive film 8th together with the thin sheet arrangements 2 can then be rolled up again, wherein to avoid mutual sticking a cover sheet 40 is hung up. This creates a role 50 comprising a multiplicity of thin-sheet arrangements which serve as 3D-capable circuit carriers for the subsequent production of the LED modules and can be intermediately stored as an intermediate product. The punched thin sheet metal foil is also rolled up again (reference numeral 20a ) and can then be sent for further utilization. By the storage of the roll 50 as an intermediate product, it is thus possible, for example, to respond very quickly to an order from a vehicle manufacturer when he places an order. For this purpose, only the rolled-up intermediate product must be taken from the warehouse, equipped with LEDs and the LED modules of the carrier film 8th be cut out and then optionally converted for the desired application. Since the LED module has the tree-like structure, a high degree of flexibility with regard to the desired arrangement of the LEDs can be ensured, so that even for different vehicle manufacturers only one equal intermediate product each must be maintained. This results in great manufacturing advantages and a quick response to orders from car manufacturers is possible. Furthermore, there is a distance between two side branches following one another on one side 3b chosen such that sufficient flexibility of the stem area 3a is possible to reproduce desired three-dimensional structures can. Preferably, a distance A (s. 1e ) between two lateral branches adjacent to one another on one side 3b such that this distance is twice as large as a length L of a carrier plate 5 in the direction of the rectilinear trunk area 3a , wherein the length L in the installed state of the carrier plates 5 is determined, ie, with bent retaining tabs 6 , This ensures sufficient flexibility of the LED module.

The LED module according to the invention 1 can thus be used in a two-dimensional manner (see 1f ) or in a three-dimensional way (see 1g ), wherein preferably the LED module 1 then on a base element 10 fixed with higher rigidity. The fixation can be done by means of the retaining tabs 6 by clipping into corresponding projections on the base element 10 respectively. The fixation of the LED module 1 on the base element 10 is in detail 6 seen. The retaining tabs can serve as cooling lugs in addition to their attachment function.

The manufacturing method according to the invention has no restrictions with regard to material, size or shape. It is particularly advantageous that simple manufacturing steps can be performed and in particular a quick installation in a headlight or on a base member 10 can be done. It is a particular advantage that the LED module according to the invention 1 can be used in both two-dimensional and three-dimensional applications. Because the LED module is soldered in the two-dimensional state and only later receives its three-dimensional shape, inexpensive standard soldering equipment can be used. Furthermore, the 3D mold carriers can vary in material, size and shape, so that completely different finished products can be produced with the production method according to the invention.

It can be used conventional, inexpensive method of manufacturing the 3D mold carrier, z. B. deep drawing, stamping or injection molding. The LED module is robust for transport and subsequent assembly steps in the headlight unit. The conversion of the two-dimensional component into a three-dimensional component takes place in a state of high degree of freedom, so that low forces a simple unrestricted, z. As robot-controlled alignment, short cycle times and high flexibility are possible. The key process of forming from the two-dimensional to the three-dimensional component makes it possible to produce a wide range of finished products in the LED sector with a wide variety of requirements, from design, dimensions, heat dissipation, etc., from a standard assembled initial product.

In the 7 and 8th Mounting variants of the LED module according to the invention are shown, in which the retaining tabs 16 in the direction of the LED 9 are bent over. Thus, the retaining tabs 16 as well as the LED 9 from a carrier plate 5 in the same direction. Accordingly, in the base member 10 a relatively large opening 10b formed by which the LED and the retaining tabs 16 are inserted through it. In 7 becomes an automated assembly by means of a vacuum gripper 11 shown which several vacuum cups 12 having, respectively, on the carrier plates 5 of the LED module engage and the LED module in the base element 10 Clip. 8th shows a caulking with two caulking 13 . 14 to the LED module on the 3D format carrier 10 to fix.

Claims (11)

Method for producing an LED module ( 1 ) with a plurality of LEDs ( 9 ), comprising the steps of: - providing a thin-plate assembly ( 2 ) with a conductor network ( 3 ), and a plurality of carrier plates ( 5 ), - applying the thin sheet assembly ( 2 ) on a flexible carrier film ( 8th ), - loading of the carrier plates ( 5 ) of the thin-plate assembly with LEDs ( 9 ), - fixing the LED's ( 9 ) on the carrier plates ( 5 ) and establishing an electrical connection between the LEDs ( 9 ) and the conductor network ( 3 ), and - free cutting of the thin sheet assembly ( 2 ) of the carrier film ( 8th ) along an outer contour of the thin sheet assembly ( 2 ) to get the LED module. Method according to claim 1, characterized in that on the carrier plate ( 5 ) Retaining tabs ( 6 ) are provided, which from a carrier plate plane of the carrier plates ( 5 ), in particular by 90 °, are bent over. Method according to one of the preceding claims, characterized in that in the retaining tabs ( 6 ) Recesses ( 7 ) are introduced. Method according to one of the preceding claims, characterized in that the fixing of the LED's ( 9 ) on the carrier plates ( 5 ) and an electrical connection between the LED ( 9 ) and the conductor network ( 3 ) is carried out by means of soldering or by welding or by caulking. Method according to one of the preceding claims, characterized in that the thin-sheet arrangement ( 2 ) is produced by means of punching or by means of lasers or by means of etching. Method according to one of the preceding claims, characterized in that the LED module ( 1 ) on a 3D mold carrier ( 10 ), preferably on a three-dimensional base element, is fixed. Method according to one of the preceding claims, characterized in that the interconnect network ( 3 ) a tree-like structure with a stem area ( 3a ) and lateral branches ( 3b ) having. LED module, comprising - a thin sheet assembly ( 2 ) with a plurality of carrier plates ( 5 ) for receiving LEDs ( 9 ) and a conductor network ( 3 ) for powering the LEDs ( 9 ), - a flexible carrier foil ( 8th ) on which the thin-sheet arrangement ( 2 ), wherein the carrier film ( 8th ) a shape corresponding to an outer contour of the thin sheet assembly ( 2 ), and - a plurality of LEDs ( 9 ), which on the carrier plates ( 5 ) are arranged and electrically connected to the interconnect network ( 3 ) are connected. LED module according to claim 8, characterized in that the interconnect network ( 3 ) a tree-like structure with a stem area ( 3a ) and a plurality of lateral branches ( 3b ) having. LED module according to claim 8 or 9, characterized in that the LED's ( 9 ) are connected in series. LED module according to one of claims 8 to 10, further comprising a 3D mold carrier ( 10 ).

Images