WO2005054745A1

WO2005054745A1 - A lamp assembly

Info

Publication number: WO2005054745A1
Application number: PCT/AU2004/001710
Authority: WO
Inventors: Ely Flaws; Andrew Papax
Original assignee: Auto Concepts Australia Pty Ltd
Priority date: 2003-12-05
Filing date: 2004-12-03
Publication date: 2005-06-16

Abstract

A lamp assembly (2) including a base portion 4 having a substantially flat printed circuit board (8), and a mounting device (6) providing at least three mounting portions (14, 16, 18), at least three light-emitting diodes (20, 22, 24) connected to the circuit board (8) and a curved optical lens portion (12) for transmitting light radiated by the light-emitting diodes. The base of each light-emitting diode is flush mounted to a respective surface of a mounting portion (14, 16, 18) such that a first of said light-emitting diodes (22) is orientated at an angle (26) with respect to a second of the light-emitting diodes (20), and a third of the light-emitting diodes (24) is orientated at an angle (28) with respect to the first light-emitting diode. The configuration of the light-emitting diodes (20, 22, 24) within the assembly is such as to distribute the light generally uniformly over the lens (12).

Description

A lamp assembly

Field of the invention

The present invention relates to a lamp assembly having a number of diodes arranged to radiate light over a range of different directions. In one preferred embodiment according to the present invention, the lamp assembly is a clearance or side light for an automotive vehicle.

Background of the Invention Lamps or lights having a number of light-emitting diodes are regularly used for example, for clearance or side lights for automotive vehicles or for general illumination requirements. These lamps typically include a series of light-emitting diodes arranged in a line and mounted to a substantially planar base, with radiated light generally being projected strongest in the axial direction of the aligned light-emitting diodes.

Such lamps normally also include a lens formed to filter and diffuse the light from the substantially point light sources provided by the light-emitting diodes. When these lamps are to be used as clearance or side lights for example, these lenses may be formed to provide a more uniform, and thereby aesthetically superior, intensity of light transmitted therethrough, or when used as an illuminating device, they may be formed to provide a more even projection of light onto the surfaces of objects to be illuminated. When mounted to automotive vehicles, clearance and side lamps or lights are often viewed by fellow drivers or pedestrians at angles oblique to the direction of travel of the vehicles. These lamps typically have a significantly reduced intensity when viewed at such oblique angles, thereby detracting from their ability to successfully radiate light and signal to observers.

In one example of a light-emitting diode based lamp, the legs of the light-emitting diodes are bent so that the light-emitting diodes are orientated at different angles. The legs of the light-emitting diodes can easily moved or break, especially when the lamp is attached to a moving object such as a vehicle.

In another example, the light-emitting diodes are arranged on a mounting plate parallel to a base level with the base of each light-emitting diode protruding into a cut-out in the mounting plate to be obliquely inclined to the base level. The substantially planar parallel arrangement of the light-emitting diodes disclosed does not produce a uniform illumination of the casing lens.

In yet another example a base portion having carrier webs that incline circuit boards and light-emitting diodes at an angle is used. This arrangement allows for the light-emitting diodes to be orientated at several different angles but requires separate circuit boards for each angle. Summary of the Invention

Preferred embodiments of the present invention seek to provide a lamp assembly that radiates light over a substantive arc and at least ameliorate the above disadvantages.

In accordance with one aspect of the present invention, there is provided a lamp assembly including: a base portion having a substantially flat printed circuit board, and a mounting device providing at least three mounting portions; at least three light-emitting diodes connected to the circuit board; and a curved optical lens portion for transmitting light radiated from the light-emitting diodes; wherein the base of each light-emitting diode is flush mounted to a respective surface of a mounting portion such that a first of said light-emitting diodes is orientated at an angle with respect to a second of the light-emitting diodes, and a third of the light-emitting diodes is orientated at an angle with respect to the first light-emitting, and wherein the configuration of the light-emitting diodes within the assembly is such as to distribute the light generally uniformly over the lens.

The bases of the light-emitting diodes are flush mounted to the mounting portions of the base portion such that they are orientated, and thereby spread the radiated light, in a range of directions. That is the base of each diode abuts a surface of a mounting portion so that the angle of the mounting portion determines the orientation of the diode. This is useful when a lamp having a number of light-emitting diodes is used as a clearance or side light on a vehicle when the light is often viewed at an angle oblique to the direction of travel, or when a lamp having a number of light-emitting diodes is used to illuminate an area where the increased spread of radiated light provides for illumination of more of the area more uniformly.

The legs of the light-emitting diodes extend through the mounting device and are soldered into the printed control board. The mounting device may be integrally formed by moulding for example. The mounting device also support the legs of the diodes to reduce the likelihood of breakage and movement of the light-emitting diodes.

Preferably, the light-emitting diodes are orientated such that the angle formed between a central axis of the first light-emitting diode and a central axis of the second light-emitting diode is substantially 45 degrees, and such that the angle formed between the central axis of the first light- emitting diode and a central axis of the third light-emitting diode is substantially 45 degrees.

In one embodiment according to the present invention, the at least three the light-emitting diodes are positioned in an arcuate array. The optical lens portion is formed to diffuse the light radiated from the light-emitting diodes and preferably has an arcuate profile. According to one preferred embodiment, the arcuate profile of the optical lens portion is substantially concentric with the arcuate array of the light-emitting diodes, such that the light-emitting diodes are positioned substantially the same effective distance from the optical lens portion to facilitate the even diffusion of the light. This is often desirable for each diode if the lamp is to be used as either a signalling or as an illuminating device.

The optical lens may also be made from an outer lens and one or more intermediate lenses between the outer lens and the light-emitting diodes. In this case the intermediate lens may be arcuate and the outer lens may be flat. In an alternative form, the intermediate lens may be moulded with an optical effect, but the outer lens clear with no pattern.

Preferably, the lamp has means for locating the mounting device relative to the printed circuit board to prevent misalignment during manufacture. The mounting device and these portions provide for the quicker and less labour intensive manufacture of the lamps, as opposed to the bending of the legs of the light-emitting diodes that may be required when the light-emitting diodes are attached directly to the printed circuit board with no intermediate mounting surface. Preferably, slots are provided in the printed circuit board and the mounting device has protruding portions engageable with in the slots to provide the locating means.

In another embodiment according to the present invention, the mounting portions are integrally formed with the mounting device. Alternatively, the mounting portions are formed from respective mounting pieces assembled together to form the mounting device. In this embodiment, the first mounting piece orientates the first light-emitting diode at a first angle, the second mounting piece orientates the second light-emitting diode at a second angle and the third portion orientates the third light-emitting diode at a third angle. Preferably, each mounting portion mounts two light-emitting diodes in adjacent relation. This provides both for the case of a failure of one of the two adjacent diodes, and increased intensity of the radiated light during normal use.

It will be appreciated that the light-emitting diodes may be orientated in a range of different planes. When the lamps according to the present invention are used as clearance or side lights for example, while it may be sufficient to spread the light-emitting diodes substantially along an arc in the one plane to radiate light, for other applications however, it may be desirable to arrange the light- emitting diodes and radiate light in a substantially greater range of directions. As an example a round dome lamp assembly for illuminating an area may have a number light-emitting diodes arranged such that all the light-emitting diodes except for a centrally located light-emitting diode are orientated in a range of different planes and directions.

Of course, the number of light-emitting diodes employed may vary considerably, along with the orientations at which they are mounted and the spacing between each angled light- emitting diode. These requirements will be governed by factors including the required light intensity, the shape of the lens, or even the desired lighting effect. Brief Description of the Drawings

Prefened embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a front plan view of a clearance light according to an embodiment of the present invention; Figure 2 is a section view of the clearance light of Figure 1 of the cross section A-

A; Figure 3 is a section view of the clearance light of Figure 1 of the cross section B- B; and Figure 4 is a section view of a clearance light according to another embodiment of the present invention.

Detailed Description

In Figures 1 to 3, a lamp assembly in the form of a clearance light 2 according to an embodiment of the present invention is shown. The clearance light 2 includes a base portion 4 having a mounting device 6, a printed circuit board 8 on which the mounting device 6 is mounted, and a clearance light base 10 on which the mounting device 6 and the printed circuit board 8 are mounted, and a curved optical lens portion in the form of a lens 12 for transmitting radiated light. The lens 12 may snap fit to the base portion 4 for example.

Three mounting portions in the form of facets 14, 16, 18 are provided in the mounting device 6, a respective pair of light-emitting diodes 20, 22, 24 flush mounted on each respective facet 14, 16, 18 for radiating light. That is the base of each diode 20, 22, 24 abuts the respective facet 14, 16, 18 so that the angle of the facet 14, 16, 18 determines the orientation of the diode 20, 22, 24. While a single light-emitting diode 20, 22, 24 may be mounted at each facet 14, 16, 18, it is preferable that two or more light-emitting diodes 20, 22, 24 are adjacently mounted at each facet 14, 16, 18 to provide for both the case of a failure of one of the diodes 20, 22, 24 if the diodes 20, 22, 24 are mounted with two or more on each facet 14, 16, 18, and to provide for increased intensity of the radiated light during normal use. Further, the number of light-emitting diodes 20, 22, 24 employed may vary considerably, along with the orientations at which they are mounted and the spacing between. These requirements will be governed by factors including the required light intensity, the shape of the lens 12, or even the desired lighting effect.

The facets 14, 16, 18 are orientated such that a first pair of the light-emitting diodes 22 are orientated at an angle as indicated by the reference numeral 26 with respect to a second pair of the light-emitting diodes 20, and a third pair of the light-emitting diodes 24 are orientated at an angle as indicated by the reference numeral 28 with respect to the first pair of light-emitting diodes 22. The light-emitting diodes 20, 22, 24 of the clearance light 2 are orientated such that the angle 26 formed between a central axis 30 of the first pair of light-emitting diodes 22 and a central axis 32 of the second pair of light-emitting diodes 20 is substantially 45 degrees, and such that the angle 28 formed between the central axis 30 of the first pair of light-emitting diodes 22 and a central axis 34 of the third pair of light- emitting diodes 24 is substantially 45 degrees. It will be appreciated that these angles are provided as an example only, and as such may be suitably varied depending on requirements. The configuration of the light-emitting diodes 20, 22, 24 of the clearance light 2 when flush mounted on the suitably orientated facets 14, 16, 18 of the mounting device 6 within the assembly is such as to distribute the light generally uniformly over the lens.

The three pairs of light-emitting diodes 20, 22, 24 are mounted on the mounting device 6 in an arcuate anay as indicated by the reference numeral 36, such that the light-emitting diodes 20, 22, 24 are all substantially the same effective distance from the curved lens, as indicated by reference numerals 38, 40, 42 respectively. The lens 12 of the clearance light 2, which is formed to diffuse the light radiated from the light-emitting diodes 20, 22, 24 such that the radiated light is spread out making it more visible in more directions as rather than being sharp dots as naked light-emitting diodes 20, 22, 24 otherwise would be, has an arcuate profile that is substantially concentric with the arc 36 on which the light-emitting diodes 20, 22, 24 are ananged, such that the light-emitting diodes 20, 22, 24 are positioned at a substantially common distance from the lens 12 to facilitate the even diffusion of the light.

While for clearance or side lights it may be sufficient to spread the light-emitting diodes 20, 22, 24 along an arc in the one plane to radiate light, for other applications, such as a dome lamp assembly (not shown) for illuminating an area for example, it may be desirable to anange the light-emitting diodes 20, 22, 24, and radiate light, in a greater range of directions. In an applicable alternative form, the light-emitting diodes 20, 22, 24 may be orientated in a range of different planes such that all the light-emitting diodes except for a centrally located light-emitting diode are orientated in a range of different planes and directions.

Further, while the clearance light 2 includes only one lens 12, it will be appreciated that there may be one or more intermediate lenses provided before the outer lens, with the same principles applying. For example the outer lens may be flat, but an intermediate lens may be curved, or in an alternative, the intermediate lens may be moulded with an optical effect, but the outer lens clear with no pattern.

The legs 44, 46 of the light-emitting diodes 20, 22, 24 extend through the mounting device 6 and are soldered into the printed circuit board 8 that controls the operation of the light- emitting diodes 20, 22, 24, as indicated by reference numeral 45. The mounting device 6 and printed circuit board 8 are held in the clearance light base 10 with an epoxy, although it will appreciated that any other means of fixing the operably connected mounting device 6 and printed circuit board 8 to the clearance light base 10 could be employed, such as screw fasteners for example (not shown). An electric current passing through electric wire 46A powers the light emitting diodes 20, 22, 24. The electrical wire 46A insulated by a protective sheath 47 that extends through a wire receiving portion 47A in the clearance light base 10. The clearance light base 10 may be fixed for example, to a vehicle by any suitable method, such as the fastening screws through apertures 47B shown in Figure 2.

While the mounting device 6 may be formed in an alternative way, by machining for example, the mounting device 6 of the clearance light 2 is integrally formed by moulding, with the shape and size determined by the desired distance from the lens 12 and angles at which the light-emitting diodes 20, 22, 24 are mounted, and the intensity of light required. Means for locating the mounting device relative to the printed circuit board to prevent misalignment during manufacture are provided in the form of protruding portions 48 extending from the mounting device 6 and corresponding slots or receiving portions (not shown) in the printed circuit board 8 for receiving the protruding portions 48 prevent misalignment of the mounting device 6 and light-emitting diodes 20, 22, 24 with respect to the printed circuit board 8 during manufacture. These portions 48 facilitate quicker alignment of the mounting device 6 and the printed circuit board 8 and a less labour intensive manufacture of the lights 2. This prevents the need to bend the legs 44, 46 of the light-emitting diodes 20, 22, 24 as otherwise may be required when the light-emitting diodes 20, 22, 24 are attached directly to the printed circuit board 8 with no intermediate mounting surface (eg. mounting device 6).

Figure 4 shows an alternative construction of the mounting device 6 as shown in Figure 2. The mounting device is formed by three mounting pieces 60, 62 and 64 which are assembled together to form the mounting device 6. The first mounting piece 62 orientates a first light-emitting diode 22 at an angle with respect to a second light-emitting diode 20 mounted on a second mounting piece 60, and a third light-emitting diode 24 mounted on a third mounting piece 64 is orientated at an angle with respect to the first light-emitting diode 22. The above embodiments of the present invention have been described by way of example only and modifications and variations may be made without departing from the spirit and scope of the invention described.

Throughout the specification, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated step or integer or group of steps or integers but not the exclusion of any other step or integer or group of steps or integers.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in Australia.

Claims

Claims:

1. A lamp assembly including: a base portion having a substantially flat printed circuit board, and a mounting device providing at least three mounting portions; at least three light-emitting diodes connected to the circuit board; and a curved optical lens portion for transmitting light radiated by the light- emitting diodes; wherein the base of each light-emitting diode is flush mounted to a respective surface of a mounting portion such that a first of said light-emitting diodes is orientated at an angle with respect to a second of the light-emitting diodes, and a third of the light-emitting diodes is orientated at an angle with respect to the first light-emitting diode, and wherein the configuration of the light-emitting diodes within the assembly is such as to distribute the light generally uniformly over the lens.

2. A lamp assembly according to claim 1 wherein the angle formed between a central axis of the first light-emitting diode and a central axis of the second light-emitting diode is substantially 45 degrees, and the angle formed between the central axis of the first light-emitting diode and a central axis of the third light-emitting diode is substantially 45 degrees.

3. A lamp assembly according to any one of the previous claims wherein the at least three light-emitting diodes are positioned in an arcuate anay.

4. A lamp assembly according to claim 3 wherein the optical lens portion has an arcuate profile.

5. A lamp assembly according to claim 4 wherein the arcuate profile of the optical lens portion is substantially concentric with the arcuate anay of light-emitting diodes, such that the light-emitting diodes are positioned substantially the same effective distance from the optical lens portion to facilitate the even diffusion of the light.

6. A lamp assembly according to any one of the previous claims wherein the optical lens includes an outer lens and at least one intermediate lens between the outer lens and the light-emitting diodes .

7. A lamp assembly according to any one of the previous claims having means for locating the mounting device relative to the printed circuit board to prevent misalignment during manufacture.

8. A lamp assembly according to claim 7 wherein slots are provided in the printed circuit board and the mounting device has protruding potions engageable in the slots to provide the locating means.

9. A lamp assembly according to any one of the previous claims wherein the mounting portions are integrally formed with the mounting device.

10. A lamp assembly according to any one of claims 1 to 8 wherein the mounting portions are formed from respective mounting pieces assembled together to form the mounting device.

11. A lamp assembly according to any one of the previous claims wherein each of the mounting portions mounts two light-emitting diodes in adjacent relation.