LED lamp

An LED lamp includes a housing defining a window therein, a cover engaging the housing, a heat sink fixed on the cover and completely received in the housing, an LED module attached to the heat sink and facing the window of the housing, and a lens engaging the window of the housing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to LED (light emitting diode) lamps and, more particularly, to an improved LED lamp having a novel structure for use outdoors.

2. Description of Related Art

LED lamp, a solid-state lighting, utilizes LEDs as a source of illumination, providing advantages such as resistance to shock and nearly limitless lifetime under specific conditions. Thus, LED lamps present a cost-effective yet high quality replacement for incandescent and fluorescent lamps.

Known implementations of LED modules in an LED lamp make use of a plurality of individual LEDs to generate sufficient light. The large number of LEDs leads to a more expensive module and one with greater power consumption. The greater power usage leads to greater heat output, which, if not adequately addressed, impacts LED lamp reliability. Therefore, various heat dissipation devices with complicated structures are exploited in the LED lamp, increasing the difficulty and cost of manufacturing the LED lamp.

What is needed, therefore, is an LED lamp with simple structure, suitable to mass-manufacture, and having satisfactory heat dissipation capability.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1-4, an LED lamp in accordance with a first embodiment is illustrated. The LED lamp comprises a substrate10, a cover20engaging the substrate10, a first heat sink30and a second heat sink31received in the substrate10and engaging the cover20, and a first LED module40and a second LED module41attached to the first and second heat sinks30,31, respectively. The LED lamp further comprises a first reflector50and a second reflector51respectively reflecting light generated by the first and second LED modules40,41, and a first lens60and a second lens61engaging the substrate10.

Referring toFIGS. 3 and 4, the substrate10substantially forms a bifurcated figure-8. The substrate10comprises a housing11with open top and bottom ends, and a supporting bar12extending from a rear end of the housing11. A first chamber13and a second chamber14are defined with different sizes in the housing11and communicate with each other. Specifically, the first chamber13is larger than the second chamber14, with both substantially columned. A first window130and a second window140are defined in the bottom end of the housing11corresponding to the first and second chambers13,14, respectively. A plurality of threaded holes15are defined in the top end of the housing11. A through hole16is defined in the rear end of the housing11to communicate with the second chamber14and the supporting bar12. A waterproof plug90is received in the hole16to prevent fluid from entering the housing11. Leading wires (not shown) can extend through the waterproof plug90and to the first and second LED modules40,41, providing power thereto. Two positioning screws80are accommodated in two holes120of the supporting bar12for threadedly engaging into a supporting post (now shown) connecting with the supporting bar12to thereby fix the LED lamp to the supporting post.

The cover20also substantially forms a bifurcated figure-8, corresponding to the housing11of the substrate10. The cover20comprises two columned walls21,22of different sizes, i.e., a first wall21and a second wall22. A first ring-shaped supporting plate23extends inwardly and horizontally from a bottom end of the first wall21, and a first connecting plate25extends outwardly and horizontally from a top end of the first wall21. A second ring-shaped supporting plate24extends inwardly and horizontally from a bottom end of the second wall22, and a second connecting plate26extends outwardly and horizontally from a top end of the second wall22. The first wall21corresponds to the first chamber13of the housing11, and the second wall22corresponds to the second chamber14. The first wall21is larger than the second wall22. The first wall21is tangential to the second wall22, and the first and second supporting plates23,24at bottom ends of the first and second walls21,22are combined. More particularly, no connecting plates25,26are disposed at the conjunction of the first and second walls21,22due to tangency therebetween. The first and second connecting plates25,26extend outwardly from part of the top ends of the first and second walls21,22other than the conjunction portion thereof. A plurality of through holes27are defined in the first and second connecting plates25,26. Screws70extend through the holes27of the first and second connecting plates25,26and into the holes15of the housing11to engage the substrate10and the cover20.

The first heat sink30and the second heat sink31have the same configuration, with the first heat sink30larger than second heat sink31. Each of the first and second heat sinks30,31comprises a round base301with a plurality of plate fins302extending from a top surface thereof. The first and second heat sinks30,31are the same height as the first and second walls21,22of the cover20. A plurality of parallel spaced channels33are defined in and perpendicular to the fins302. The first heat sink30is arranged on the first supporting plate23of the cover20, and the second heat sink31is arranged on the second supporting plate24of the cover20.

The first LED module40and the second LED module41have a same configuration, with the first LED module40being larger than the second LED module41. Each of the first and second LED modules40,41comprises a mounting board401and a plurality of LEDs402radially mounted thereon. The first LED module40is attached to a bottom surface of the base301of the first heat sink30. The second LED module41is attached to a bottom surface of the base301of the second heat sink31.

The first and second reflectors50,51are respectively mounted on the first and second LED modules40,41and fixed to the bottom surfaces of the bases301of the first and second heat sinks30,31. A plurality of apertures502are defined in the first and second reflectors50,51. Each aperture502corresponds to an LED402.

The first and second lenses60,61are transparent or semitransparent material such as glass, plastic, or other, allowing light emitted by the first and second LED modules40,41to project therethrough to illuminate the surrounding environment. The first and second lenses60,61are respectively fixed to the first and second windows130,140of the housing11.

In assembly, the first and second lenses60,61respectively engage the first and second windows130,140of the housing11. The first LED module40and the first reflector50are fixed to the bottom surface of the base301of the first heat sink30, and the second LED module41and the second reflector51are fixed to the bottom surface of the base301of the second heat sink31. The first heat sink30assembled with the first LED module40and the first reflector50is fixed to the first supporting plate23of the cover20. The second heat sink31assembled with the second LED module41and the second reflector51is fixed to the second supporting plate24of the cover20. The cover20assembled with the first and second heat sinks30,31, the first and second LED modules40,41and the first and second reflectors50,51engages the housing11by the screws70extending through the holes27of the cover20and into the holes15of the housing11. The first and second walls21,22and the first and second supporting plates23,24are received in the housing11. The first heat sink30, the first LED module40and the first reflector50are received in the first chamber13of the housing11. The second heat sink31, the second LED module41and the second reflector51are received in the second chamber14of the housing11. The first and second LED modules40,41face the first and second windows130,140, respectively. Tops of the fins302of the first and second heat sinks30,31and the first and second connecting plates25,26of the cover20are coplanar; that is, the first and second heat sinks30,31are completely received in the cover20, as well in the housing11.

In operation, light generated by the first and second LED modules30,31projects through the first and second lenses60,61and towards the outside of the housing11. The first and second heat sinks30,31absorb heat from the first and second LED modules40,41for dissipation into the ambient air. The first and second heat sinks30,31accommodated in the cover20further serve as protective components preventing external fluid and solid contaminants from entry into housing11. Further, since the first and second heat sinks30,31are completely received in the housing11, the fins302of the first and second heat sinks30,31remain contained within the housing11, such that aesthetic appearance of the LED lamp is maintained. The first and second heat sinks30,31completely received in the housing11, also reduce the volume of the LED lamp, thus to enhance portability and ease of assembly and disassembly of the LED lamp.

Referring toFIGS. 5-7, an LED lamp in accordance with a second embodiment is illustrated. The LED lamp comprises a substrate10a, a cover20aengaging the substrate10a, a heat sink30areceived in the substrate10aand engaging the cover20a, and an LED module40aattached to the heat sink30a. The LED lamp further comprises a reflector50amounted on the LED module40a, a lens60aengaging the substrate10a, and a rectifier55electrically connected with the LED module40aand received in the substrate10a.

The substrate10ais similar to the substrate10of the LED lamp in the previous embodiment, and substantially forms a bifurcated figure-8. The substrate10acomprises a housing11aand a supporting bar12aextending from a rear end of the housing11a. The housing11adiffers from housing11only in that a window130ais defined in a bottom end of the housing11acorresponding to a first chamber13a, where a bottom end of the housing11acorresponding to a second chamber14ais closed. The first chamber13ais larger than the second chamber14a. The heat sink30a, the LED module40aand the reflector50aare received in the first chamber13a. The rectifier55is received in the second chamber14a.

The cover20acomprises a columned wall21a, a ring-shaped supporting plate23aextending inwardly and horizontally from a bottom end of the wall21a, and a ring-shaped connecting plate25aextending outwardly and horizontally from a top end of the wall21a. A ring-shaped connecting plate26aextends horizontally from a rear end of the connecting plate25a. The connecting plate26ais smaller than the connecting plate25aand tangential to the connecting plate25a, whereby the cover20asubstantially forms a bifurcated figure-8 and has a profile similar to that of the housing11a. The wall21aand the supporting plate23aare received in the first chamber13aof the housing11a. A plurality of threaded holes231ais defined in the supporting plate23a. A waterproof cushion291is arranged on the supporting plate23a. A plurality of through holes27ais defined in the connecting plates25a,26a. Screws70can extend through the holes27aof the connecting plates25a,26aand enter holes15aof the housing11ato fix the cover20aonto the housing11a. An inner edge of the connecting plate26ais depressed downwardly to form a ring-shaped supporting plate24a. Another waterproof cushion292is arranged on the supporting plate24a. A round shield28covers the supporting plate24ato protect the rectifier55received in the second chamber14aof the housing11a.

The heat sink30acomprises a round base301aand a plurality of parallel fins302aextending from a top surface of the base301a. A plurality of through holes35are defined in edges of the base301a. Screws36can extend through the holes35and into the holes231aof the supporting plate23ato fix the heat sink30ato the supporting plate23aof the cover20a.

The LED module40acomprises a plurality of longitudinal boards401aand a plurality of LEDs402ain alignment on each of the boards401a. The LED module40ais attached to a bottom surface of the base301aof the heat sink30a. The reflector50ais mounted on the LED module40aand fixed to the heat sink30a. A plurality of apertures502ais defined in the reflector50a. Each aperture502acorresponds to each LED402a. The lens60ais fixed to the window130aof the housing11a.