LED Light Fixture with Facilitated Lensing Alignment and Method of Manufacture

• US 20120281404A1
• Filed: 04/06/2012
• Published: 11/08/2012
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: IDEAL Industries Lighting, LLC (Ideal Industries Incorporated)
• Original Assignee: Ruud Lighting Incorporated (Wolfspeed, Inc.)
• Inventors: Wilcox, Kurt S., Strom, Christopher, Raleigh, Craig
• Granted Patent: US 9,404,634 B2
• Time in Patent Office: Days
• US Class Current: 362/244
• CPC Class Codes: F21S 2/005 of modular construction
• CPC Class Codes: F21V 25/12 Flameproof or explosion-proof arrangements
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21V 31/005 Sealing arrangements therefor
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21W 2131/103 of streets or roads
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: Y10T 29/49895 Associating parts by use of aligning means [e.g., use of a drift pin or a "fixture"]

Abstract

LED lighting apparatus including (1) a plurality of primary lenses each over a corresponding one of LED arrays spaced on a circuit board, and (2) a one-piece lensing member over the circuit board and having a plurality of secondary lenses each spaced over one of the primary lenses on the circuit board, the circuit board and lensing member having first and second mating features positioned and configured for inter-engagement for high-precision lens alignment. The circuit board and one-piece lensing member are each joined to a mounting surface of a heat-conductive member, and such assembly, while facilitating high-efficiency assembly, does not interfere with high-precision lens alignment.

Claims

1. A method of assembling an LED light fixture, the fixture including (a) a heat-conductive structure having a mounting surface, (b) a circuit board having a plurality of LED arrays spaced thereon with a plurality of primary lenses each over a corresponding one of the LED arrays and (c) a one-piece lensing member having a plurality of secondary lenses each positioned to align with a corresponding one of the primary lenses, the method comprising:

providing a set of mounting holes through the circuit board and a set of alignment holes in the circuit board;

providing a set of mounting holes through the one-piece lensing member and a set of alignment protrusions extending from a circuit-board-adjacent surface of the lensing member;

providing first and second sets of fastener-receiving cavities in the heat-conductive structure and open at the mounting surface thereof;

mounting the circuit board to the mounting surface by inserting a first set of fasteners through the circuit-board mounting holes into the first set of fastener-receiving cavities;

aligning the lensing member with respect to the circuit board by mating engagement of the alignment protrusions with the alignment holes; and

installing the lensing member over the circuit board by inserting a second set of fasteners through the lensing-member mounting holes into the second set of fastener-receiving cavities.

2. The method of claim 1 wherein the set of alignment protrusions includes first and second protrusions and the set of alignment holes includes a first hole complementary in shape to the first protrusion to fix the position of the lensing member along the circuit board, and a second hole to receivie the second protrusion and prevent rotation of the lensing member about the first protrusion.

3. The method of claim 2 wherein the second hole is elongate along a line extending between the first and second holes thereby to facilitate the mating engagement.

4. The method of claim 1 wherein the one-piece lensing member has a peripheral portion extending beyond the edge of the circuit board.

5. The method of claim 4 wherein the peripheral portion encircles the circuit board and engages a gasket providing a weathertight seal around the circuit board.

6. The method of claim 5 wherein:

the one-piece lensing member is of a polymeric material; and

compression-limiting inserts are in each of the holes of the one-piece lensing member.

7. Lighting apparatus comprising:

a plurality of primary lenses each over a corresponding LED array, the LED arrays spaced on a circuit board, the circuit board having a first mating feature;

a one-piece lensing member over the circuit board and including a plurality of secondary lenses each spaced over a corresponding one of the primary lenses, the one-piece lensing member having a second mating feature positioned and configured for mating engagement with the first mating feature, the first and second mating features engaged to accurately align the secondary lenses over their corresponding primary lenses.

8. The lighting apparatus of claim 7 wherein:

the second mating feature is a protrusion extending from a circuit-board-adjacent surface of the one-piece lensing member; and

the first mating feature is a complementary hole formed in an LED-supporting surface of the circuit board.

9. The lighting apparatus of claim 8 wherein:

the lensing member includes first and second protrusions extending from the circuit-board-adjacent surface; and

the circuit board defines a first hole complementary in shape to the first protrusion to fix the position of the lensing member along the circuit board, and a second hole receiving the second protrusion to prevent rotation of the lensing member about the first protrusion.

10. The lighting apparatus of claim 9 wherein the second hole is elongate along a line extending between the first and second holes thereby to facilitate engagement of the mating features.

11. The lighting apparatus of claim 7 further including a heat-conductive structure having a mounting surface and having first and second sets of fastener-receiving cavities, the circuit board being mounted to the heat-conductive structure with fasteners extending through mounting holes in the circuit board into the first set of fastener-receiving cavities.

12. The lighting apparatus of claim 11 wherein the one-piece lensing member is secured to the heat-conductive structure with fasteners inserted through holes in the one-piece lensing member into the second set of fastener-receiving cavities.

13. The lighting apparatus of claim 12 wherein the one-piece lensing member has a peripheral portion extending beyond the edge of the circuit board.

14. The lighting apparatus of claim 13 wherein the peripheral portion encircles the circuit board and engages a gasket providing a weathertight seal around the circuit board.

15. The lighting apparatus of claim 14 wherein:

the one-piece lensing member is of a polymeric material; and

compression-limiting inserts are in each of the holes of the one-piece lensing member.

16. Lighting apparatus comprising:

a plurality of LED light sources spaced on a circuit board, the circuit board having a first aligning feature;

a lensing member over the circuit board and including a plurality of lenses each spaced over a corresponding one of the LED light sources, the lensing member having a second aligning feature positioned and configured for alignment with the first aligning feature to align the lenses over their corresponding LED light sources.

17. The lighting apparatus of claim 16 wherein:

the second aligning feature is a protrusion extending from a circuit-board-adjacent surface of the one-piece lensing member; and

the first aligning feature is a complementary hole formed in an LED-supporting surface of the circuit board.

18. The lighting apparatus of claim 17 wherein:

the lensing member is a one-piece member which includes first and second protrusions extending from the circuit-board-adjacent surface; and

the circuit board defines a first hole complementary in shape to the first protrusion to fix the position of the lensing member along the circuit board, and a second hole receiving the second protrusion to prevent rotation of the lensing member about the first protrusion.

19. The lighting apparatus of claim 18 wherein the second hole is elongate along a line extending between the first and second holes thereby to facilitate engagement of the mating features.

20. The lighting apparatus of claim 16 wherein each LED light source includes an array of LEDs.

21. The lighting apparatus of claim 20 wherein each light source includes a primary lens over the LED array.

22. The lighting apparatus of claim 21 wherein each of the primary lenses is overmolded on one of the LED arrays.