SG190461A1

SG190461A1 - A light bulb system

Info

Publication number: SG190461A1
Application number: SG2011084845A
Authority: SG
Inventors: Christopher George Edward Nightingale; Swee Ming Goh; Teck Wee Ang; Boon Hou Tay; Chonghe Shao; Yu Zhang
Original assignee: Alternative Energy Technology Pte Ltd; Jiashan Ao Naji Dianzi Youxian Gongsi
Priority date: 2011-11-16
Filing date: 2011-11-16
Publication date: 2013-06-28

Abstract

A LIGHT BULB SYSTEMA light bulb system 10 is disclosed comprising a plurality of discrete lightsources 26 which are orientated so that at least two of the discrete light sources 26 emit light different in directions. The light sources 26 are arranged into respective lighting subsystems 32 and 34 on respective printed circuit boards or chips. The lighting subsystems 32, 34 are mounted about a supporting column 46 which in turn is attached to a heat sink 14. A base 12 is attached to the heatsink 14 and configured to engage an electrical socket to provide at least a part of an electrical conduction path from the socket to the lighting subsystem 32,34. A cover 24 is demountably couple to the base via the heat sink 14 and envelopes the lighting subsystems 32, 34.Fig. 1

Description

A LIGHT BULB SYSTEM

Field of the Invention

The present invention relates to a light bulb system, and in particular but not : exclusively to a light bulb system that can be used as a replacement for conventional light bulbs including tungsten bulbs.

Background of the Invention

A conventional incandescent light bulb also known as a tungsten bulb comprises a tungsten filament enclosed within an inert gas environment by a glass cover. Such bulbs are particularly energy inefficient with approximately 90% of power consumed by the bulb being emitted as heat rather than light.

The cover enveloping the filament typically comes in three common shapes, namely, candle, globe and pear-shape. There are also two common types of base for coupling the bulb to a socket namely the screw type base (E27) and a bayonet type base (such as for example the base B22).

From about the mid 1990s, compact fluorescent lamps have also become commercially available for domestic use. Such lamps often comprise a folded or wound glass tube filled with a high pressure vapour. An electronic ballast is incorporated in the lamp. The compact fluoro lamp is available in the base selection as the incandescent or tungsten lamp. A substantive benefit of the compact fluoro lamp is its significantly greater energy efficiency. However such lamps also contain mercury as a vapour which is hazardous to health and environment.

Summary of the Invention

In one aspect the invention provides a light bulb system comprising: a lighting system comprising a plurality of discrete light sources wherein at least two of the discrete light sources are arranged to emit light different in directions; a base configured to engage an electrical socket and provide at least a part of an electrical conduction path from the socket to the lighting system: and,

a demountable cover configured to detachable couple to the base and envelop the lighting system, the demountable cover being transmissive to light emitted by the discrete light sources.

Ina second aspect the invention provides a light bulb system comprising: a plurality of lighting subsystems, each lighting subsystem comprising a printed circuit board (PCB) provided with a lighting circuit having and one or more discrete light sources, a positive terminal and a negative terminal: a column supporting at least two of the lighting subsystems in relative juxtaposition wherein the discrete light sources of the respective PCB emit light in different directions; and, a base coupled to the column and configured to engage an electrical socket and provide at least a part of an electrical conduction path from the socket to each of the lighting subsystems.

In a third aspect the invention provides a light bulb system comprising: a plurality of first lighting subsystems, each lighting subsystem comprising a printed circuit board (PCB) supporting a lighting circuit comprising and one or more discrete light sources and a positive terminal and a negative terminal near one end of the PCB, and the PCBs extending about and parallel to a common axis; a connection ring provided with an opening and current transfer circuit extending about the opening, the PCBs extending into the opening wherein the positive and negative terminals of the PCBs are electrically connected to the current transfer circuit; and, a base configured to engage an electrical socket and in electrical contact with the current transfer circuit wherein electrical current flows from the base through the current transfer circuit and to each of the lighting subsystems.

In a fourth aspect the invention provides a light bulb system comprising: a plurality of lighting subsystems, each lighting subsystem comprising a chip-on-board LED array having and one or more discrete light sources, a positive terminal and a negative terminal; a column supporting at least two of the lighting subsystems in relative juxtaposition wherein the discrete light sources of the respective chip-on-board

LED array emit light in different directions: and,

a base coupled to the column and configured to engage an electrical socket and provide at least a part of an electrical conduction path from the socket to each of the lighting subsystems.

Embodiments of the present invention enable replacement or interchanging of the cover of the light bulb system so as to vary the shape, colour or degree of transparency.

In one embodiment the light bulb system comprises a driver circuit electrically coupled between the base and lighting system or lighting subsystems wherein the driver circuit is one of: a non-dimmable driver, a non-dimmable driver with power factor correction feature, a dimmable driver, or a dimmable driver with power factor correction feature. 16 In addition in some embodiments where the discrete light sources are mounted on printed circuit boards, the printed circuit boards may be provided with a film or layer of white or reflective material to redirect light which may impinge from the light sources on to the PCBs through the cover.

Brief Description of the Drawings

Embodiments of the invention will be described by way of examples only with reference to the accompanying drawings in which:

Figure 1 is an exploded view of one embodiment of a light bulb system in accordance with the present invention:

Figure 2 illustrates a first variation in a cover incorporated in the bulb system shown in Figure 1;

Figure 3 illustrates a second variation in a cover incorporated in the bulb system shown in Figure 1;

Figure 4 is a representation of a first type of lighting subsystem incorporated in the bulb system shown in Figure 1;

Figure 5 is a representation of a second form of lighting subsystem incorporated in the light bulb system shown in Figure 1;

Figure 6 is a partial view of a ring connector incorporated in the light bulb system; and,

Figure 7 is a circuit diagram of the light bulb system.

Detailed Description of Further Embodiments

Accompanying Figures 1 and 3 — 7 illustrate an embodiment of a light bulb system 10 in accordance with the present invention. The light bulb system 10 comprises a number of interconnected components which, when assembled and connected to an electrical power source via an electrical socket, generates and emits light. The connection to a socket is via a base 12 (also known in the art as a “cap”) of the light bulb system 10.

In the illustrated embodiment the base 12 is illustrated as a screw base designated in the art as E27. It is to be appreciated that embodiments of the present invention are not limited to this type of base 12 and any other known base configuration can be used such as for example: E10, E11, E12, E14, E17,

E26 or bayonet type bases such as B22, B15; fluorescent type connectors such as GS or G13; or, strip lamp connectors S14. The function of the base 12 isto provide mechanical and electrical connection for the bulb system 10 to an electrical socket. In this way the base 12 also provides at least a part of an electrical connection path for the bulb system 10.

Base 12 is connected to a heat sink 14 via an intervening back cover 16. To this end the base 12 is press fit into the back cover 16 which in tunis connected to the heat sink 14 by a number of screws 18. The back cover 16 is made from electrical insulating materials such as a ceramic material or a plastic material or bakelite.

The heat sink 14 is made of a high thermal conducting material such as aluminium or brass or copper and this embodiment is in the form of an annulus.

Heat sink 14 performs various functions. One is to provide a heat sink for electronic components of the light bulb system 10. Another is to house a driver circuit 20 incorporated in the light bulb system 10. Further the heat sink 14 acts as a connector or attachment point for both a lighting system 22, and a demountable cover 24 of light bulb system 10.

Lighting system 22 comprises a plurality of discrete light emitting devices 26 which in the present embodiment are in the form of light emitting diodes (LEDs).

The lighting system 22 is arranged so that at least two of the discrete light sources, e.g. LEDs 26, emit light in different directions. More particularly in this embodiment the lighting system 22 comprises a plurality of lighting subsystem each subsystem comprising a lighting circuit having one or more LEDs 26, a positive terminal 28, and a negative terminal 30. In one variation LED chips can be used in place of discrete LEDs.

A first type of lighting subsystem 32 is illustrated in Figure 4 and a second type of lighting subsystem 34 is depicted in Figure 5. The substantive difference between the subsystems 32 and 34 is their respective shape and relative juxtaposition in the assembled light bulb system 10.

Lighting subsystem 32 comprises a rectangular shaped printed circuit board (PCB) 36a on which the corresponding lighting circuit is provided. In this embodiment the lighting circuit for the subsystem 32 comprises five LEDs 26 which are connected in series by a conductor track 38 printed on the PCB 36a.

Each of the LEDs 26 is a discrete electronic component having a plurality of connection pins which are soldered onto the conducting pin marks 40 on PCB 36a to provide electrical connection with the printed conductor track 38. Each of the positive and negative terminals 28 and 30 are located near one end 42 of the PCB 36a. Two fastening holes 44 are formed in the PCB 36a to enable mechanical connection to a central supporting column 46.

With reference to Figure 5, the second lighting subsystem 34 differs from the first lighting system 32 only in terms of the shape of its printed circuit board 36b.

In this instance, the printed circuit board 36b is hexagonal in shape. The lighting subsystem 34 comprises five series connected LEDs 26 which are connected together via printed conductor 38. Opposite ends of the electrical circuit on the board 36b are provided with positive and negative terminals 28 and 30. Two fastening holes 44 are also formed in the PCB 36b to enable connection to the supporting column 46.

A third type of lighting subsystem (not shown) which may be used in the light bulb system 10 is a chip-on-board LED array in which two or more LED Chips are placed in intimate contact with a custom designed, thermally efficient : substrate structure (where the chip LED PN junction temperature is lower than that of LED 26). The substrate structure takes the shape of a linear strip. The : third type of lighting subsystems can be uses as a substituted for lighting subsystem 32.

In the present light bulb system 10, the lighting subsystems 32 and 34 are supported on the column 46. Column 46 has a longitudinal axis 48 extending in a direction from the base 12 to the cover 24 and a hexagonal cross sectional shape. Thus column 46 has six faces or surface portions which extend about the axis 48. Six first lighting subsystems 32 are connected, one to each surface 16 portion of the column 46. The first lighting subsystems 32 are orientated so that their respective positive and negative terminals 30 are adjacent the heat sink 14. Each first lighting system 32 is attached to the column 46 by a pair of screws 50 one of each passing through the holes 44 and into corresponding thread holes in the column 46.

The second lighting system 34 is coupled to an upper end of the column 46 so as to be orientated or disposed in a plane perpendicular to the axis 48. The corresponding PCB 36b is attached to the upper end of column 46 by a further pair of screws 50 passing through respective holes 44 and into threaded holes in the column 46.

In this particular embodiment there are six lighting subsystems 32 extending parallel to and about the axis 48 with respective adjacent first lighting subsystems 32 angularly offset by 60°. Thus each of the first lighting subsystems 32 and the second lighting subsystem 34 direct light in different directions.

The column 46 is made from a heat conductive material such as aluminium or brass or copper and acts to transfer heat generated by the LEDs 26 to the heat 85 sink 14. Column 46 is mechanically and thermally attached to the heat sink 14 by a plurality of metallic screws 52.

The first lighting subsystems 32 are electrically connected to the base 12 via a connection ring 54 shown in Figures 1 and 6. The connection ring 54 comprises a current transfer circuit which is arranged to connect with the positive and negative terminals 28 and 30 of the lighting subsystems 32. More particularly the connection ring 54 comprises a printed circuit board 56 which supports the current transfer circuit. The current transfer circuit comprises a plurality of positive terminals 58 which are electrically connected together, and a number of negative terminals 60 which are electrically connected together.

The terminals 58 and 60 are disposed on an inside surface 62 of the connection ring 54 at locations to register with and physically contact positive and negative terminals 28 and 30 of each of the first lighting subsystems 32. The inner surface 62 defines an opening 64 in the connection ring 54. An outer circumferential surface 66 of the PCB 56 seats in a groove (not shown) formed in the heat sink 14.

When the light bulb system 10 is assembled, the column 46 with the connected lighting subsystems 32 and 34 is inserted into the opening 64 so that the positive and negative terminals 28 and 30 are in physical contact with the positive and negative terminals 58 and 60 of the connection ring 54. The PCB 56 is a double-sided PCB so that a portion of the current transfer circuit which connects together the positive terminal 58 is on one side, while a portion of the current transfer circuit which connects together the next terminal 60 on an opposite side. A through connector (not shown) enables both positive and negative sides of the circuit to be connected to respective positive and negative terminals 66, 68 of the driver circuit 20 and subsequently the base 12.

The driver circuit 20 is electrically coupled between the base 12 and lighting system 22 or lighting subsystems 32/34 and can be either one of: a non- dimmable driver; a non-dimmable driver with power factor correction feature; a dimmable driver; or a dimmable driver with power factor correction feature.

Electrical connection to the second lighting subsystem 34 is via wires (not shown) that connect the corresponding terminals 28 and 30 to the positive terminal 66 and negative terminal 68 of driver circuit 20.

As shown in Figure 7, the LEDs 26 in a particular lighting subsystem 32 or 34 are connected in series with each other. However the lighting subsystems 32 and 34 are connected in parallel to each other. The parallel arrangement helps to improve the redundancy of the lighting subsystems, especially in the event when one lighting subsystem is faulty, the remaining subsystems are still able to emit light. The driver circuit 20 typically comprises an AC to DC converter so as to convert an AC input into a DC output. Active and neutral inputs 70 and 72 of the driver circuit 20 are electrically connected by wires 74 and 76 to the base 12.

Cover 24 shown in Figure 1 is in the shape of a conventional bulb and may be made from a glass or plastics material with a selected degree of transmissivity (i.e. a transparency) as well as in a range of different colours. The cover 24 is provided with a threaded neck 78 which is configured to threadingly engage with a corresponding thread (not shown) formed on an inside surface of the heat sink 14. In this way, the cover 24 can be made of one of a number of 156 shapes and configurations and interchanged or replaced as desired. For example Figure 2 illustrates an alternate form of cover 24' having a candle shape, while Figure 3 illustrates a further form of cover 24" of a spherical shape (also known as “omni” shape).

Now that an embodiment of the present invention has been described in detail it would be obvious to those of ordinary skill in the art that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the present lighting system 22 is depicted as comprising six first lighting subsystems 32 each formed on planar rectangular

PCBs, and a single second lighting subsystem 34 formed on a planner hexagonal shaped PCB. The second lighting subsystem 34 lies in a plane perpendicular to respective planes of the lighting subsystem 32, and indeed the axis 48. However in alternative embodiments, the second lighting subsystem 34 may be disposed obliquely to the axis 48. Indeed, multiple second lighting subsystems 34 may be provided each of which is orientated in different oblique planes to the axis 48. Further, rather than six first lighting subsystems 32, alternative embodiments of the light bulb system 10 may comprise an alternate number of lighting subsystems for example three, four or eight. Further, each of the subsystems 32 is presently depicted as being formed on a planar rectangular PCB 36a. However in alternative embodiments the PCBs may have an arcuate cross section for example in the shape of a semi-circle with the column 46 being in the form of a cylinder. Also, the driver circuit 20 is described as comprising an AC to DC converter.

However, in alternative embodiments the driver 20 may comprise a DC to DC converter, that converts a variable DC input to a fixed DC voltage output.

All such modifications and variations together with others that would be obvious to persons or ordinary skill inthe art are deemed to be within the scope of the present invention, the nature of which is to be determined from the above description and the appended claims.

Claims

The claims defining the invention are as follows:

1. A light bulb system comprising: a lighting system comprising a plurality of discrete light sources wherein atleast two of the discrete light sources are arranged to emit light different in directions; a base configured to engage an electrical socket and provide at least a part of an electrical conduction path from the socket to the lighting system; and, a demountable cover configured to detachable couple to the base and envelop the lighting system, the demountable cover being transmissive to light emitted by the discrete light sources.

2. The light bulb system according to claim 1 wherein the light system comprises a plurality of lighting subsystems each comprising a lighting circuit having and one or more discrete light sources, a positive terminal and a negative terminal.

3. The light bulb system according to claim 2 wherein the plurality of lighting subsystems comprises a group of one or more first lighting subsystems the first lighting subsystems extending about and parallel to a common axis.

4, The light bulb system according to claim 3 wherein the plurality of lighting subsystems comprises a group of one or more second lighting subsystems, each of the second lighting subsystems being orientated oblique or perpendicular to the common axis.

5. The light bulb system according to claim 3 or 4 comprising a column supporting the lighting subsystems and coupled to the base, the column disposed substantially co-axial with the common axis.

6. The light bulb system according to any one of claims 2 to 5 wherein each lighting subsystem comprises a printed circuit board (PCB) on which the discrete light sources are mounted and positive and negative terminals formed.

7. The light bulb system according to claim 5 wherein the PCBs corresponding of the first lighting subsystems are coupled to a portion of the column disposed about the common axis.

8. The light bulb system according to claim 5 or 6 wherein the PCBs corresponding to the second lighting subsystems coupled to a portion of the column oblique or perpendicular to the common axis.

9. The light bulb system according to any one of claims 1 to 8 wherein each discrete light source is a light emitting diode (LED) or a LED chip.

10. The light bulb system according to any one of claims 3 to 9 comprising a connection ring provided with an opening and current transfer circuit extending about the opening, wherein the base is electrically connected to the current transfer circuit and the PCBs corresponding to first lighting subsystems extending into the opening wherein the positive and negative terminals of these PCBs are in physical contact with and thereby electrically connected to the current transfer circuit.

11. The light bulb system according to claim 10 wherein the connection ring comprises a PCB and the current transfer circuit comprises conductors printed on that PCB.

12. The light bulb system according to any one of claims 5 to 11 comprising a heat sink connected between the base and the column.

13. The light bulb system according to claim 12 wherein the connection ring is disposed in and in contact with the heat sink.

14. The light bulb system according to claim 12 or 13 wherein the demountable cover is demountably connected to the heat sink.

15. Alight bulb system comprising: a plurality of lighting subsystems, each lighting subsystem comprising a printed circuit board (PCB) provided with a lighting circuit having and one or more discrete light sources, a positive terminal and a negative terminal; a column supporting at least two of the lighting subsystems in relative juxtaposition wherein the discrete light sources of the respective PCB emit light in different directions; and,

16. The light bulb system according to claim 15 wherein the plurality of lighting subsystems comprises two or more first lighting subsystems wherein the PCBs corresponding to the first lighting subsystems are coupled to a portion of the column disposed about a longitudinal axis of the column.

17. The light bulb system according to claim 15 wherein the plurality of lighting subsystems comprises: one or more first lighting subsystems wherein the PCBs of the first lighting subsystems are coupled to a portion of the column disposed about a longitudinal axis of the column; and, one or more second lighting subsystems, wherein the PCBs of the second lighting subsystems are 16 coupled to a portion of the column orientated oblique or perpendicular to the common axis.

18. The light bulb system according to 16 or 17 comprising a connection ring provided with an opening and current transfer circuit extending about the opening, wherein the base is electrically connected to the current transfer circuit and the PCBs corresponding to first lighting subsystems extending into the opening wherein the positive and negative terminals of these PCBs are in physical contact with and thereby electrically connected to the current transfer circuit.

19. The light bulb system according to claim 18 wherein the connection ring comprises a PCB and the current transfer circuit comprises conductors printed on that PCB.

20. The light bulb system according to any one of claims 15 to 19 comprising a heat sink connected between the base and the column.

21. The light bulb system according to claim 20 wherein the connection ring is disposed in and in contact with the heat sink.

22. The light bulb system according to claim 20 or 21 comprising a cover demountably connected to the heat sink and being: arranged to envelop the lighting subsystems; and, transmissive to light emitted by the discrete light sources.

23. Alight bulb system comprising: a plurality of first lighting subsystems, each lighting subsystem comprising a printed circuit board (PCB) supporting a lighting circuit comprising and one or more discrete light sources and a positive terminal and a negative terminal near one end of the PCB the PCBs extending about and parallel to a common axis; a connection ring provided with an opening and current transfer circuit extending about the opening, the PCBs extending into the opening wherein the positive and negative terminals of the PCBs are electrically connected to the current transfer circuit; and, a base configured to engage an electrical socket and in electrical contact with the current transfer circuit wherein electrical current flows from the base through the current transfer circuit and to each of the lighting subsystems.

24. The light bulb system according to claim 23 comprising a heat sink connected between the base and the lighting subsystems.

25. The light bulb system according to claim 24 wherein the connection ring is disposed in and in contact with the heat sink.

26. The light bulb system according to claim 24 or 25 comprising a cover demountably connected to the heat sink.

27. The light bulb system according to any one of claims 23 to 26 wherein the plurality of lighting subsystems comprises a group of one or more second lighting subsystems, each of the second lighting subsystems being orientated oblique or perpendicular to the common axis.

28. The light bulb system according to any one of claims 23 to 27 comprising a column supporting the lighting subsystems and coupled to the base, the column disposed substantially co-axial with the common axis.

29. Alight bulb system comprising:

a plurality of lighting subsystems, each lighting subsystem comprising a chip-on-board LED array having and one or more discrete light sources, a positive terminal and a negative terminal; a column supporting at least two of the lighting subsystems in relative juxtaposition wherein the discrete light sources of the respective chip-on-board LED array emit light in different directions; and, a base coupled to the column and configured to engage an electrical socket and provide at least a part of an electrical conduction path from the socket to each of the lighting subsystems.

30. The light bulb system according to claim 29 wherein the plurality of lighting subsystems comprises two or more first lighting subsystems wherein the chip-on-board LED arrays corresponding to the first lighting subsystems are coupled to a portion of the column disposed about a longitudinal axis of the column.

31. The light bulb system according to claim 29 wherein the plurality of lighting subsystems comprises: one or more first lighting subsystems wherein the chip-on-board LED arrays of the first lighting subsystems are coupled to a portion of the column disposed about a longitudinal axis of the column; and, one or more second lighting subsystems, wherein the chip-on-board LED arrays of the second lighting subsystems are coupled to a portion of the column orientated oblique or perpendicular to the common axis.

32. The light bulb system according to 30 or 31 comprising a connection ring provided with an opening and current transfer circuit extending about the opening, wherein the base is electrically connected to the current transfer circuit and the chip-on-board LED arrays corresponding to first lighting subsystems extending into the opening wherein the positive and negative terminals of these chip-on-board LED arrays are in physical contact with and thereby electrically connected to the current transfer circuit.

33. The light bulb system according to claim 32 wherein the connection ring comprises a PCB and the current transfer circuit comprises conductors printed on that PCB.

34. The light bulb system according to any one of claims 29 to 33 comprising a heat sink connected between the base and the column.

35. The light bulb system according to claim 32 wherein the connection ring is disposed in and in contact with the heat sink.

36. The light bulb system according to claim 34 or 35 comprising a cover demountably connected to the heat sink and being: arranged to envelop the lighting subsystems; and, transmissive to light emitted by the discrete light sources.

37. The light bulb system according to any one of claims 1 to 14 comprising a driver circuit electrically coupled between the base and lighting system wherein the driver circuit is one of: a non-dimmable driver, a non-dimmable driver with power factor correction feature, a dimmable driver, or a dimmable driver with power factor correction feature.

38. The light bulb system according to any one of claims 15 to 36 comprising a driver circuit electrically coupled between the base and the lighting subsystem wherein the driver circuit is one of: a non-dimmable driver, a non-dimmable driver with power factor correction feature, a dimmable driver, or a dimmable driver with power factor correction feature.