HK1164418A - Flat modulus light source - Google Patents

Description

Flat modular light source

Cross Reference to Related Applications

The present chinese application claims priority from U.S. provisional patent application No.61/389,496 filed on day 4, 10/2010, which is incorporated herein by reference.

Technical Field

The present invention relates to a lighting device for illumination. In a preferred embodiment, the lighting device is a flat modular light source with an LED light source comprising one or more LED chips.

Background

Conventionally, a bulb for a light source may be a compact halogen lamp or an incandescent lamp. In recent years, in terms of illumination, LEDs, such as LEDs having a separate collimating lens, have been proposed and used. However, such LED light sources do not provide uniform light from the light source and thus may be uncomfortable to the eye.

Lighting units using light reflected from LEDs are known. Specifically, the spotlights DOM6 LED 600L 3500K 120HSG of the lighting by lighting company (Lithonia lighting) provides a spotlight that reflects light downward. However, a bright-through cell is a large and heavy fixture with a heat sink on top of the cell, and such a cell is not compatible with standard lighting fixture standards (e.g., GX 53). There is therefore a need for a light source that is small in size and light in weight, on the one hand, that can be used as a light bulb, for example a replacement light bulb for use with a standard light holder, and at the same time can provide uniform light without causing eye discomfort.

Disclosure of Invention

According to one aspect of the invention, a lighting device comprises: an upper cover having a stepped cylindrical profile layered to constitute an upper portion of the lighting device; a generally annular heat sink having a circular profile around its outer perimeter and a hexagonal profile around its inner perimeter and shaped to have an opening at the bottom of the heat sink; a plurality of LEDs arranged around an inner perimeter of the heat sink, the LEDs oriented to emit light at an angle in an upward direction; and a hexagonal reflector positioned between the upper housing and the heat sink, the hexagonal reflector having a downwardly reflective lower surface. When the lighting device is assembled and power is supplied to the LED, light emitted from the LED is reflected off the lower surface of the reflector to exit through the opening in the bottom of the heat sink.

In another aspect, the lighting device further includes an AC-DC driver that converts electrical energy external to the light source into a signal suitable for driving the LEDs.

In yet another aspect, an AC-DC driver is snapped into the interior of the upper housing and includes a securing button (knob) protruding from an aperture in the upper portion of the upper housing, the securing button configured to mate with a lamp fixture/socket to provide power to the AC-DC driver.

In yet another aspect, an AC-DC driver is snapped into the interior of the upper housing and includes first leads extending from one or more apertures in the upper portion of the upper housing, the first leads configured to couple with an external power source to provide power to the AC-DC driver.

In another aspect, the shape of the inner perimeter of the heat sink is hexagonal.

In yet another aspect, the LEDs are mounted on a flexible PCB that is folded to lie on a surface of the inner perimeter of the heat sink.

In yet another aspect, the LED is mounted on circuitry printed directly on a surface of the inner perimeter of the heat sink and including a copper layer on which the LED is secured, the copper layer being coupled to the AC-DC driver.

In another aspect, the inner perimeter is sloped.

Drawings

The figures are for illustration purposes only and are not necessarily drawn to scale. The invention itself, however, will be best understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view of a flat modular light source according to an embodiment of the present invention;

FIG. 2 is an exploded view of a flat modular light source according to an embodiment of the present invention;

FIG. 3A is a perspective view of a heat sink member with LEDs and associated circuitry for use in a flat modular light source according to an embodiment of the present invention;

FIG. 3B is a cross-sectional view of the heat sink member shown in FIG. 3A taken along line 3B;

FIGS. 4A and 4B are side cross-sectional views of flat modular light sources according to embodiments of the present invention;

FIG. 5 is a cross-sectional view of a flat modular light source according to another embodiment of the present invention; and

fig. 6 is an exploded view of a flat modular light source according to the embodiment of the invention shown in fig. 5.

Detailed Description

Fig. 1-4B illustrate a first preferred embodiment of a flat modular light source according to the present invention. As seen in the figures, the flat modular light source 1 according to an embodiment of the present invention is composed of an upper housing 10, an AC-DC driver module 11a, the driver module 11a having a wing-like plate 12, on which plate 12 a fixing knob 13 is mounted. Also provided are a reflector 14 having a reflective upper surface, as well as a heat sink 16 and a lens cover 18.

Preferably, the upper housing 10 has a layered cylindrical shape as shown. Preferably, the drive module 11a may be mounted within the housing 10 by snapping or screwing into a second large perimeter surface of the housing. The cover 10 is formed such that the outermost portion (i.e. the largest perimeter) can fit snugly around the upper edge of the heat sink 16 when the light source 1 is mounted. Preferably, the outermost portion of the upper housing is dimensioned to enable the light source 1 to be compatible with and snugly fit within a standard socket/fixture, such as the known GX53 socket/fixture. Preferably, the upper housing 10 is constructed of plastic or other moldable material.

Preferably, the light reflecting member 14 is hexagonal in shape having a light reflecting surface on a lower surface thereof. The light-reflecting surface may be provided by making the light-reflecting component 14 of light-reflecting metal or by using light-reflecting paint. The light reflecting elements 14 are supported on and cooperate with hexagonal inner rings 22 formed within the heat sink 16. The LEDs 15 are mounted on the surface of the inner ring 22 around the inner periphery of the heat sink 16.

In a preferred embodiment, the LEDs are mounted on a flexible pcb (fpcb)17 folded in a hexagonal shape and secured (e.g., by gluing) to an inner surface 22 of the heat sink 16. The electrical connection between the driver module 11a and the FPCB is provided by a wire 26 a. Although the illustrated embodiment shows the folded FPCB, the present invention is not limited to this structure. For example, a small piece of PCB may be provided, one piece for each LED, with wire connections between each piece of PCB to obtain electrical connections. As another example, the LEDs may be mounted on circuitry such as insulators and copper layers, which are printed directly on the inner surface of the heat sink. Such an embodiment will be discussed below with reference to fig. 3A and 3B.

The bottom of the heat sink 16 includes an annular lower portion 20, the annular lower portion 20 being upwardly arched toward the center of the heat sink 16, and the interior being open to allow the reflected light from the LEDs to exit the light source 1. Preferably, the hexagonal edges forming the inner surface 22 are formed around the inner perimeter of the heat sink 16.

Preferably, the light source 1 comprises a bottom cover or lens cover 18. Lens cover 18 may be made of plastic or other similar material and may be frosted (i.e., light diffusing) to provide more diffuse light for eye comfort. The lens cover 18 may also be transparent. In any case, the lens cover protects the light source 1 from dust, dirt and moisture, except for modifying the light source. The lens cover 18 is also designed to include a collimating lens or a plurality of collimating lenses to allow the light exiting the light source 1 to have a relatively tight angle.

In the embodiment shown in fig. 1 and 2, the light source utilizes an AC/DC driver module 11a to power the LEDs. Preferably, the AC-DC driver module 11a has a wing-like plate 12 on which a fixing knob 13 is mounted. The fixing knob 13 is arranged to obtain power when fixed to a lamp socket, such as a GX53 lamp socket, and to apply power to an AC-DC driver module which converts the input power into a DC signal that can be used to drive LEDs. The actual circuitry forming the AC-DC driver may be of any known type that converts AC electrical energy into a DC drive signal. Then, a DC signal is supplied to the FPCB 17 via the wire 26a to drive the LEDs.

Preferably, the AC-DC driver module 11a with the wires 12 and the securing knob 13 has a profile compatible with standard lighting fixture mounting standards (such as the known GX53 standard) to enable the light source to be mounted into any standard GX53 lamp socket. Thus, the fixing knob 13 may be configured to be compatible with such a lamp socket. Of course, the invention is not limited to having a shape compatible with the GX53 lamp base. Preferably, the AC-DC driver module 11a is formed such that the AC-DC driver module 11a can be snapped or screwed into the interior of the upper housing 10.

Fig. 3A and 3B illustrate another method of applying LEDs to the inner surface 22 of the heat sink 16. In this embodiment, rather than using a FPCB, the LEDs are attached to the circuitry, which has been printed directly on the inner surface 22 of the heat sink, for example by solder joints 160. This direct printed circuitry has an insulator 170 and a copper layer 180. Circuitry receives voltage from conductor 26a to drive the LED, conductor 26a is coupled to copper layer 180 and is also soldered to AC-DC driver module 11 a. The lead wires 26a penetrate the upper cover 10. Copper layer 180 includes circuitry for applying drive voltages and other voltages to the individual LEDs. For example, copper layer 180 may have a thickness of about 0.1 mm. The walls of the inner surface of hexagonal rim 22 are diagonally upwardly inclined to cause the LED light to be emitted upwardly at an angle. The upwardly inclined light rays are then reflected by the light reflecting member 14 and then emitted downward out of the bottom of the light source 1. The type of LED used may vary depending on brightness and heat dissipation, but may include, for example, a Cree MX6 or Cree XPE LED.

In assembling the light source 1, the hexagonal light reflecting members 14 are placed over the hexagonal edges 22 so as to be supported on top of the edges 22. Such a configuration advantageously enables light rays emitted upward from the LED to be reflected at a downward angle and exit the bottom of the light source 1. The upper cover 10 may be fixed to the heat sink, for example, by snap (snap fit). If a lens cover 18 is used, it is also attached to the bottom of the heat sink, for example by snapping.

Fig. 4A and 4B are functional cross-sectional views of a light source according to an aspect of the present invention, but without showing details of the circuitry or AC-DC drive circuit discussed above. The arrows in fig. 4A and 4B show how light rays emitted from the LEDs are directed towards the reflector 14 and redirected away from the bottom of the light source 1. In fig. 4A and 4B, the light path from the LED15 is reflected off the light reflecting surface 14 and then downward out of the light source 1 as indicated by the arrow.

In the embodiment shown in fig. 1 and 2, the light source provides power to the LEDs using an AC/DC driver module 11a having a stationary knob 13, the stationary knob 13 being used to couple with an external power source, such as a wall or ceiling AC power source. Another embodiment is shown in fig. 5 and 6. In the embodiment shown in fig. 5 and 6, the light source receives external power not through the fixing knob of the AC-DC driver module, but the wire 26 is provided to supply AC power to the AC-DC driver module 11 b.

As shown, the wires 26 enter holes in the top of the upper housing 10 and are connected to the AC-DC driver module 11 b. As in the case of the embodiment of fig. 1 and 2, the signal converted by the driver module 11b is supplied to the LED via the conductor 26b connected to the FPCB 17. Other elements of the embodiment shown in fig. 5 and 6 having similar reference numerals are the same as those described in fig. 1-4B and the light source operates in the same manner, such as that shown in fig. 4A and 4B. As is the case with the structures shown in fig. 1 and 2, in the structures shown in fig. 5 and 6, the LEDs may be attached to the FPCB 17, or alternatively, may be attached to a single die PCB, or may be attached to directly printed circuitry as shown in fig. 3A and 3B. The description of these same aspects will not be repeated here.

The use of wires rather than fixed buttons provides the flexibility of allowing connection to other socket types or line connectors. The wires may be connected to any plug to mate with a power outlet in a different country or may be directly connected to an external power source by an electrician. There may be 2-3 wires depending on the drive design and whether AC or DC is to be used. In the case of 2 conductors, the conductors may typically be live and neutral. In the case of 3 conductors, these may be live, neutral and ground.

Preferably, in either embodiment, the lens cover 18 is a transparent, frosted or other light diffusing cover that softens the light emitted from the LEDs 15 that has been reflected. The upper edge of the lens cover 18 is shaped to couple to the heat sink 16 by, for example, snapping. Preferably, the cover 18 is made of a transparent polymer with high light transmittance (for example, PC, PMMA, PVC or PU), or other plastic or glass, or any other material that can transmit light.

Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof.

Claims (8)

1. An illumination device, comprising:

an upper cover having a stepped cylindrical profile layered to constitute an upper portion of the lighting device;

a generally annular heat sink having a circular profile around its outer perimeter and a hexagonal profile around its inner perimeter and shaped to have an opening at the bottom of the heat sink;

a plurality of LEDs arranged around an inner perimeter of the heat sink, the LEDs oriented to emit light at an angle in an upward direction; and

a hexagonal reflector positioned between the upper housing and the heat sink, the hexagonal reflector having a lower surface that is downwardly reflective,

wherein when the lighting device is assembled and power is provided to the LED, light emitted from the LED is reflected off of the lower surface of the reflector to exit through the opening in the bottom of the heat sink.

2. The lighting device of claim 1, further comprising:

an AC-DC driver that converts electrical energy external to the light source into a signal suitable for driving an LED.

3. The lighting device of claim 2, wherein the AC-DC driver is snapped into the interior of the upper housing and includes a securing button protruding from an aperture in the upper portion of the upper housing, the securing button configured to mate with a lamp fixture/socket to provide power to the AC-DC driver.

4. The lighting device of claim 2, wherein the AC-DC driver is snapped into the interior of the upper housing and comprises first wires extending from one or more apertures in the upper portion of the upper housing, the first wires configured to couple with an external power source to provide power to the AC-DC driver.

5. The illumination device of claim 1, wherein an inner perimeter of the heat sink is hexagonal in shape.

6. The lighting device of claim 1 or 5, wherein the LEDs are mounted on a flexible PCB that is folded to lie on a surface of an inner perimeter of the heat sink.

7. The lighting device of claim 2 or 5, wherein the LEDs are mounted on circuitry printed directly on a surface of an inner perimeter of the heat sink and comprising a copper layer on which the LEDs are affixed, the copper layer being coupled to the AC-DC driver.

8. The illumination device of claim 1, wherein the inner perimeter is sloped.