Electro-optical assembly having heat dissipation, and method for producing such an assembly

Abstract

An assembly (1) comprises at least one base plate (2), a counter plate (3) connected thereto, and an electro-optical element (4). The base plate (2) is provided with at least one conductor track (7) for connecting the electro-optical element (4), and with at least one heat transfer element (5) for dissipating heat from the electro-optical element (4). The heat transfer element (5) is a heat-conductive operative connection between the electro-optical element (4) and the counter plate (3).

Claims

1.-12. (canceled)

13. An assembly (1), comprising: at least one injection-molded MID (Molded Interconnect Device) component (2); a metal part (3) connected thereto; and an electro-optical element (4), the MID component (2) being provided with at least one conductive track (7) for connecting the electro-optical element (4) and with a heat transfer element (5) for dissipating heat from the electro-optical element (4), wherein the heat transfer element (5) is a thermally conductive operative connection between the electro-optical element (4) and the metal part (3).

14. The assembly (1) as claimed in claim 13, wherein the MID component (2) is formed from a plastic material.

15. The assembly (1) as claimed in claim 13, wherein the injection-molded MID component is produced in a 2C (2-component) method and/or in a LDS (laser direct structuring) method.

16. The assembly (1) as claimed in claim 13, wherein the metal part (3) is a heat sink (3).

17. The assembly (1) as claimed in claim 13, wherein the metal part (3) is formed from a thermal conductor material.

18. The assembly (1) as claimed in claim 13, wherein the heat transfer element (5) is a metal insert.

19. The assembly (1) as claimed in claim 13, wherein the heat transfer element (5) is a metal pin (5).

20. The assembly (1) as claimed in claim 13, wherein the MID component (2) provides a receptacle (6) for the heat transfer element (5).

21. The assembly (1) as claimed in claim 20, wherein the injection-molded MID component is a base plate (2) having a base plate plane, and wherein the metal part is a counter plate (3).

22. The assembly (1) as claimed in claim 21, wherein the receptacle (6) for the heat transfer element (5) is a reception groove (6) which extends from the electro-optical element (4) to the counter plate (3).

23. The assembly (1) as claimed in claim 21, wherein the receptacle (6) for the heat transfer element (5) is a reception groove (6) extending perpendicularly to a base plate plane.

24. The assembly (1) as claimed in claim 21, wherein the heat transfer element (5) is injected into the receptacle (6) by overmolding in an injection-molding method.

25. The assembly (1) as claimed in claim 21, wherein the heat transfer element (5) is pressed into the receptacle (6).

26. A method for producing the assembly (1) as in claim 13, comprising: injection-molding the MID component (2) from an LDS (Laser Direct Structuring) material; overmolding the heat transfer element (5) during the injection-molding of the MID component (2) or pressing the heat transfer element (5) in after the injection-molding of the MID component (2); forming a recess for a conductive track (7) in the MID component (2) by partial laser activation/laser radiation; coating or metallizing the recess for the conductive track (7); applying the electro-optical element (4) on the MID component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Various embodiments of the invention will be explained in more detail below with reference to FIGS. 1 to 5, in which:

[0048] FIG. 1 shows a schematic sectional view of an assembly according to a first embodiment;

[0049] FIG. 2 shows a schematic sectional representation of a detail from the assembly;

[0050] FIG. 3 shows a perspective view of the assembly according to a further embodiment, and

[0051] FIG. 4 shows a perspective view from above of the assembly according to a further embodiment, and

[0052] FIG. 5 shows a perspective view from below of the assembly according to the embodiment of FIG. 4.

DETAILED DESCRIPTION

[0053] The figures contain partially simplified, schematic representations. Identical reference signs are sometimes used for elements which are equivalent but possibly not identical. Different views of the same elements could be scaled differently.

[0054] FIG. 1 schematically shows a sectional representation of an assembly 1, consisting of a base plate 2, a counter plate 3, three electro-optical elements 4 and respectively three heat transfer elements 5 for dissipating heat from the respective electro-optical element 4 to the counter plate 3.

[0055] In this embodiment, the base plate 2 is formed from LDS-capable material. In another embodiment, the base plate 2 may be formed from a powder-coated metal, the powder coating containing an LDS-capable additive.

[0056] In the present example, the electro-optical element 4 is configured as an LED, in particular as a high-performance LED. However, other embodiments which use further lighting means, such as incandescent bulbs, are hereby also disclosed.

[0057] The heat transfer element 5 is received in a reception groove 6 provided for the heat transfer element 5. The reception groove 6 is formed in the base plate 2. The reception groove 6 corresponds in its extent in the z direction to a thickness of the base plate 2, so that the reception groove 6 is a reception opening that extends from a first base plate plane to the opposite second base plate plane.

[0058] The reception groove 6 corresponds in its extent in the x direction at least to a width of the electro-optical element, preferably to a smaller width and particularly preferably to one third of the width of the electro-optical element.

[0059] The reception groove 6 corresponds in its extent in the y direction at least to a width of the electro-optical element in the y direction, preferably to a larger width of the electro-optical element.

[0060] The heat transfer element 5 extends in its reception groove 6 perpendicularly from the electro-optical element 4 in the z direction to the counter plate 3. The heat transfer element 5 corresponds in its extent in the z direction at least to the thickness of the base plate 2, so that the heat transfer element 5 extends and/or passes through from the first base plate plane to the opposite second base plate plane.

[0061] In one exemplary embodiment, the heat transfer element may be a metal pin 5 formed from thermally conductive metal, in particular a metal pin 5 formed from brass.

[0062] The counter plate 3 shows cooling fins 3′ in FIG. 1, the cooling fins comprising recesses 3″. Cooling fins 3′ formed in such a way have an increased surface area for optimized heat dissipation from the counter plate 3 into the surroundings. Such a configuration furthermore achieves a large cooling surface of the counter plate 3 with a small overall size. A heat flux is created in such a way that the heat produced at the electro-optical element is absorbed by means of the heat transfer element 5 and dissipated in the z direction onto the cooling counter plate 3. Heat buildup on a heat-sensitive plastic base plate 2 is thereby prevented and remains functionally capable for a long time.

[0063] FIG. 2 shows a schematic representation of a detail from the assembly 1, wherein the base plate 2, the electro-optical element 4, the heat transfer element 5, the receptacle 6 for the heat transfer element 5 and a conductive track 7 for connecting the electro-optical element 4 are shown.

[0064] On its side facing toward the base plate, the electro-optical element 4 according to FIG. 2 comprises at least one contact foot 4a for connecting to the conductive track 7 and at least one contact foot 4b for contacting the heat transfer element 5. Preferably, the at least one contact foot 4b of the electro-optical element 4 and the heat transfer element 5 are in direct contact. In test runs, direct contact between the electro-optical element 4 and the heat transfer element 5 has shown that the amount of heat produced can be dissipated directly to the heat transfer element 5. Consequently, the plastic base plate 2 remains free from accumulating heat and deformation is prevented.

[0065] The heat transfer element 5 in its reception groove 6 corresponds in its extent in the x direction at least to a width of the electro-optical element 4, preferably to a smaller width and particularly preferably at least to the width of the contact foot 4b of the electro-optical element 4.

[0066] The heat transfer element 5 in its reception groove 6 corresponds in its extent in the y direction at least to a width of the electro-optical element 4 in the y direction, preferably to a larger width of the electro-optical element. A heat transfer element protruding beyond the electro-optical element 4 in the y direction ensures that, in particular, high-performance LEDs can be used.

[0067] FIG. 3 shows a perspective view of the assembly according to a further embodiment, consisting of the base plate 2, the heat transfer element 5 and a further heat transfer element 5′, 5″. The reception groove 6 for the heat transfer element 5 and a further reception groove 6′ with laterally opposite offshoots 6″ for the heat transfer element 5′, 5″ are furthermore represented.

[0068] According to FIG. 3, the heat transfer element 5 is a metal pin 5 pressed into its reception groove 6 after the injection-molding method. The reception groove 6 is a reception groove 6 stamped out likewise after the injection-molding method.

[0069] The heat transfer element 5′, 5″ is injected into its reception groove 6′ with lateral offshoots 6″ by means of overmolding in an injection-molding method. According to FIG. 3, an H-shaped configuration is produced for the heat transfer element, its branches 5″ orientated parallel to one another having a substantially larger heat absorption surface in comparison with its connecting pin 5′ for the branches 5″ orientated parallel to one another. The comparatively thin connecting pin 5′ is preferably provided for contacting with the electro-optical element 4, and the connecting pin 5′ is particularly preferably provided for contacting the contact foot 4b of the electro-optical element 4. The heat, absorbed at the connecting pin 5′, from the electro-optical element 4 is removed via the connecting pin 5′ on the one hand to its terminally connected branches 5″ orientated parallel to one another and removed on the other hand directly to the cooling counter plate 3.

[0070] Providing an H-shaped heat absorption surface on the heat transfer element 5′, 5″ offers the advantage that a large contact area is produced for rapid and reliable absorption and subsequent removal of the heat from the electro-optical element 4 to the cooling counter plate 3. The H-shaped configuration of the heat transfer element 5′, 5″ extends from a connecting plane for the electro-optical element 4 of the base plate 2 to the opposite connecting plane for connecting to the counter plate plane of the base plate 2. An H-shaped heat delivery surface to the counter plate 3 is consequently provided on the heat transfer element 5′, 5″.

[0071] FIG. 4 shows an assembly with the base plate 2 and the heat transfer element 5, the heat transfer element 5 being configured as a metal pin 5, and the conductive tracks 7 not being explicitly represented. Furthermore, at least one elevation 8, preferably two to four elevations and particularly preferably 64 to 128 elevations on a base plate 2, is provided for applying an electro-optical element 4. In particular, the elevations 8 on the base plate 2 are orientated at an inclined angle with respect to the first base plate plane. The first base plate plane is precisely the plane which is represented visibly in FIG. 4. The inclined elevations 8 and the base plate 2 are configured in one piece. Preferably, the elevations 8 are molded in the injection-molding method for producing the base plate 2. The inclination of the elevations 8 is used for orientation of the electro-optical element 4, so that variable inclination angles for the elevations 8 may be provided depending on the requirement for the orientation of the light beam of the electro-optical element 4.

[0072] Preferably, the inclination angle of the elevations 8 for orientating the electro-optical elements 4, measured at the first base plate plane, is 45°, particularly preferably less than 45°, measured from the first base plate plane.

[0073] One reception groove 6 respectively for respectively one heat transfer element 5 is provided in the base plate 2. The respectively one reception groove 6 is advantageously a stamped reception groove 6. The reception groove 6 extends from respectively one elevation 8 of the base plate 2 of the first base plate plane to the opposite-lying second base plate plane. The respective heat transfer element 5 is received in its reception groove 6 and correspondingly extends into the elevation 8. In this way, the heat-removing heat transfer element 5 is provided precisely at the connection region of the electro-optical element 4.

[0074] In particular, a first end of the heat transfer element 5 is orientated with an inclination, specifically in a manner corresponding to the inclination angle of the elevation 8 on the first base plate plane, and a second end is configured extending parallel to the opposite second base plate plane. The first end of the heat transfer element 5 thus terminates in a form-fit with the inclined surface of the elevation 8, and the second end of the heat transfer element 5 terminates in a form-fit with the surface of the opposite-lying second base plate plane (cf. FIG. 4, FIG. 5).

[0075] According to FIG. 4 and FIG. 5, the heat transfer element 5 is a stamped metal pin 5. The metal pin 5 then extends from the inclined elevation 8 of the base plate plane on the one hand to the opposite base plate plane on the other hand. Furthermore, the metal pin 5 is orientated perpendicularly to the first base plate plane and perpendicularly to the opposite-lying base plate plane.

[0076] A fastening opening 9, as represented in FIG. 4, is used to apply the assembly at a desired position. The present exemplary embodiment provides that the assembly is applied on a fixing rod. The fixing rod is preferably formed from a thermally conductive material, so that the fixing rod is used as a heat sink. The heat produced at the electro-optical element 4 can then be removed onto the fixing rod and a further counter plate 3 does not need to be provided.

[0077] Preferably, the base plate 2 is a base plate 2 formed from metal, so that the heat can be absorbed by means of the heat transfer element 5 and removed via the metal base plate 2 onto the cooling fixing rod (not represented). Furthermore preferably, a thermally conductive paste and/or thermally conductive foil (not represented) is provided at the junction from the metal base plate 2 to the fixing rod. Particularly preferably, the thermally conductive paste and/or thermally conductive foil fully fills air inclusions so as to allow form-fit fixing of the base plate 2 on the fixing rod. The form-fit fixing has the advantage that efficient heat removal onto the cooling fixing rod is achieved.

[0078] It is thus clear that the assembly 1 can be adapted economically to different geometrical requirements. If a cooling fastening possibility exists at the desired application position of the assembly, for example, it is expedient to omit a base plate 2.

[0079] FIG. 5 shows a perspective view of the assembly 1 represented in FIG. 4 from below, wherein the base plate 2, the at least one heat transfer element 5 and the fastening opening 9 for fastening the assembly 1 on a fixing rod (not represented) are shown. The base plate 2 represented in FIG. 5 shows the second base plate plane lying opposite the first base plate plane.

[0080] Numerous further exemplary embodiments are possible, for example the following:

[0081] Embodiment 1: An assembly consisting of at least one base plate, a counter plate connected thereto and an electro-optical element, the base plate being provided with at least one conductive track for connecting the electro-optical element and with at least one heat transfer element for dissipating heat from the electro-optical element, characterized in that the heat transfer element is a thermally conductive operative connection between the electro-optical element and the counter plate.

[0082] Embodiment 2: The assembly according to embodiment 1, characterized in that the base plate is formed from a plastic material.

[0083] Embodiment 3: The assembly according to either of the preceding embodiments, characterized in that the base plate is an injection-molded component, in particular an MID (Molded Interconnect Device) component.

[0084] Embodiment 4: The assembly according to embodiment 3, characterized in that the injection-molded MID component is produced in particular in the 2C (2-component) method and/or in the LDS (laser direct structuring) method.

[0085] Embodiment 5: The assembly according to one of the preceding embodiments, characterized in that the counter plate is a heat sink.

[0086] Embodiment 6: The assembly according to one of the preceding embodiments, characterized in that the counter plate is formed from a thermal conductor material, preferably a metal.

[0087] Embodiment 7: The assembly according to one of the preceding embodiments, characterized in that the heat transfer element is a metal insert, in particular a metal pin.

[0088] Embodiment 8: The assembly according to one of the preceding embodiments, characterized in that the base plate provides a receptacle for the heat transfer element.

[0089] Embodiment 9: The assembly according to embodiment 8, characterized in that the receptacle for the heat transfer element is a reception groove which extends from the electro-optical element to the counter plate, in particular is a reception groove extending perpendicularly to a base plate plane.

[0090] Embodiment 10: The assembly according to embodiment 9, characterized in that the heat transfer element is injected into the receptacle by means of overmolding in an inj ection-molding method.

[0091] Embodiment 11: The assembly according to embodiment 9, characterized in that the heat transfer element is pressed into the receptacle.

[0092] Embodiment 12: A method for producing this assembly according to embodiments 1 to 11, or another assembly consisting of at least one base plate and at least one electro-optical element, the base plate being provided with at least one conductive track for connecting the electro-optical element and with at least one heat transfer element for dissipating heat from the electro-optical element, containing the following steps: [0093] provision of the base plate, wherein the base plate is injection-molded from an LDS (Laser Direct Structuring) material; and [0094] the heat transfer element is overmolded in the injection-molding method of the base plate; or [0095] the heat transfer element is pressed in after the injection-molding method of the base plate; [0096] partial laser activation/laser radiation of the base plate so that a recess for a conductive track is formed; [0097] coating/metallization of the recess for the conductive track, a copper, nickel or gold coating is preferably used for the metallization; [0098] application of the electro-optical element.

[0099] Even though various aspects or features of the invention are respectively shown in the figures in combination, it is clear to a person skilled in the art—unless otherwise indicated—that the combinations represented and discussed are not the only possible ones. In particular, mutually corresponding units or feature complexes from different exemplary embodiments may be replaced with one another.

LIST OF REFERENCE SIGNS

[0100] 1 assembly

[0101] 2 MID component, base plate

[0102] 3 metal part, counter plate

[0103] 3′ cooling fins

[0104] 3″ recesses

[0105] 4 electro-optical element

[0106] 4a contact foot for connecting to conductive track 7

[0107] 4b contact foot for contacting the heat transfer element 5

[0108] 5 heat transfer element or metal pin

[0109] 5′ connecting pin

[0110] 5″ branches orientated parallel to one another

[0111] 6 reception groove

[0112] 7 conductive track

[0113] 8 elevations on base plate 2

[0114] 9 fastening opening