Device supporting a light-emitting diode for an automobile signalling system, and a method of manufacturing such a device

• US 20040029436A1
• Filed: 05/27/2003
• Published: 02/12/2004
• Est. Priority Date: 05/27/2002
• Status: Active Grant

• Current Assignee: Valeo Vision (Valeo SE)
• Original Assignee: Valeo Vision (Valeo SE)
• Inventors: Tanghe, Alcina, Gasquet, Jean-Claude
• Granted Patent: US 6,821,143 B2
• Time in Patent Office: Days
• US Class Current: 439/490
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 2201/10553 Component over metal, i.e. metal plate in between bottom of component and surface of PCB
• CPC Class Codes: H05K 2201/10924 Leads formed from a punched metal foil affixing a prefabricated self-supporting metal foil pattern H05K3/202
• CPC Class Codes: H05K 3/202 using self-supporting metal foil pattern
• CPC Class Codes: H05K 3/3421 Leaded components

Abstract

The object of the invention is a device supporting a power light-emitting diode for an automobile signalling or lighting system, comprising an insulating support (2) and means of electrical connection to the electrodes (1a, 1b) of the diode (1). The electrical connection means comprise, on the insulating support (2), electrical connection lugs (17a, 17b); the body of the light-emitting diode (1) is fixed to an area of a heat-radiating element (8); this heat-radiating element (8) is attached to the insulating support (2), and the electrodes (1a, 1b) of the diode are insulated from the heat-radiating element and electrically connected to the connecting lugs (17a, 17b) of the insulating support by tongues (12a, 12b) insulated from the radiating element (8) after the breakage of temporary fasteners (13).

Claims

1. Device supporting a power light-emitting diode for an automobile signalling or lighting system, comprising an insulating support, in particular made from plastics material, and means of electrical connection to the diode electrodes, characterised by the fact that the electrical connection means comprise, on the insulating support (2), electrical connection lugs (17a, 17b;

217a, 217b);

the body (1c) of the light-emitting diode (1) is fixed to an area (8c) of a heat-radiating element (8;

308, 408, 508);

this heat-radiating element is attached to the insulating support (2;

302, 402, 502), and the electrodes (1a, 1b) of the diode are insulated from the heat-radiating element and electrically connected to the connection lugs (17a, 17b;

217a, 217b) of the insulating support.

2. Device according to claim 1, characterised by the fact that the heat-radiating element (8;

308, 408, 508) comprises, on its contour, at least one scallop (10a, 10b) in the direction of the light-emitting diode fixing area, that at least one of the diode electrodes (1a, 1b) is disposed in a corresponding scallop (10a, 10b) in the radiating element, and that the electrical connection means comprise, in the scallop or in each scallop, a tongue (12a, 12b;

112a, 112b;

212a, 212b;

312a-512b) made from electrically conductive material whose edges are distant from those of the scallop and whose external radial end is situated in the vicinity or beyond the external contour of the radiating element.

3. Device according to claim 1 or 2, characterised by the fact that the power light-emitting diode can produce a light flux of at least 30 lumens.

4. Device according to one of claims 1 to 3, characterised by the fact that the fixing area (8c) for the base of the light-emitting diode (1) consists of the central area of the radiating element (8), which comprises two opposite scallops (10a, 10b) starting from its contour and directed towards the central area, each electrode (1a, 1b) of the diode being situated respectively in a scallop, and an electrically conductive tongue (12a, 12b;

112a, 112b;

212a, 212b) being situated in each scallop and being connected to the corresponding electrode, the edges of the tongue being distant from those of the scallop.

5. Device according to claim 2 or 4, characterised by the fact that the tongue (12a, 12b;

112a, 112b) consists of a part cut from the sheet or plate forming a radiator, in correspondence with a scallop (10a, 10b).

6. Device according to one of claims 2, 4 or 5, characterised by the fact that the edge of the tongue (112a, 112b) remote from the light-emitting diode (1) projects beyond the contour of the radiating element (8).

7. Device according to one of the preceding claims, characterised by the fact that the radiating element (8;

308, 408, 508) and the insulating support (2;

302, 402, 502) are connected by cooperation of holes (9, 11a, 11b, 14, 16) provided in the radiating element and pins or studs (3, 4, 5, 6) provided on the insulating support.

8. Device according to one of the preceding claims, characterised by the fact that the diode electrodes (1a, 1b) are spot welded, in particular by laser.

9. Device according to one of the preceding claims, characterised by the fact that the insulating support in a single piece comprises several plates (302, 402, 502) situated in offset parallel planes and connected by inclined walls (18, 19), each plate being equipped with a power diode (301, 401, 501) fulfilling a given function.

10. Method of manufacturing a support device according to one of the preceding claims, characterised by the fact that there are prepared separately an insulating support (2;

302, 402, 502), in particular made from plastics material, provided with electrical connection lugs (7a, 17a, 217a;

7b, 17b, 217b), and a radiating assembly (8;

308, 408, 508) comprising a power light-emitting diode, and that the radiator and insulating support are assembled mechanically whilst providing the electrical connection of the diode electrodes (1a, 1b) with the connecting lugs.

11. Method according to claim 10, characterised by the fact that the radiating assembly (8;

308, 408, 508) is produced from a sheet or plate of metal which conducts heat and electricity, in particular copper, from which there are partially cut, on each side of a central area (8c), tongues (12a, 12b;

112a, 112b) which remain temporarily connected by fasteners (13) with a reduced cross-section, forming shunts, to the major part (8a, 8b) of the sheet or plate in order to ensure its coherence and mechanical holding;

the light-emitting diode (1) is positioned and fixed, in particular by adhesive bonding, to the central area (8c) of the radiating element;

each diode electrode (1a, 1b) is welded with a respective tongue and the connecting shunts (13) between tongues and radiating element are next broken so as to provide the electrical insulation of each tongue vis-à

-vis the radiating element.

12. Method according to claim 11, characterised by the fact that the connecting shunts (13) between a tongue (12a, 12b) and the radiating element (8) have sufficient cross-section to provide mechanical holding, but relatively small so as to limit the discharge of heat through the shunts when the electrodes are welded to the tongues.