AU2019101102A4 - An electrical light fitting - Google Patents

Abstract

The electrical light fitting 1 includes an elongate body 2 configured for installation into a ceiling. The elongate body 2 includes an upper gear tray 3, an intermediate chassis 4 and a lower trim 5. Electrical components 6 are disposed on the gear tray. Light-emitting hardware 7 is mounted upon the lower side of the upper horizontal member 8. The elongate body 2 defines a pair of air flow channels 11, each extending between a lower end 13 and an upper end 14 for air conditioning purposes. The lower ends 13 of the air flow channels 11 are either visually obscured, or minimally visible, when viewed from a vantage point below and spaced from the lower side. The lower ends 13 of the air flow channels 11, which are shaped as longitudinal slots 15, are substantially orthogonal to the ceiling. 8//-7 AIR FLOW Fig. 8 6g7 g Fig. 9

Description

AN ELECTRICAL LIGHT FITTING

TECHNICAL FIELD

The present invention relates to an electrical light fittings of the type that may be installed into ceilings, for example in offices and the like. Embodiments of the present invention find application, though not exclusively, in construction and renovation.

BACKGROUND ART

Any discussion of documents, acts, materials, devices, articles or the like which has been included in this specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed in Australia or elsewhere before the priority date of this application.

Known electrical light fittings typically define air flow paths that provide a passageway for air to travel between a room and the cavity above the ceiling of the room. This is required for air conditioning purposes; either for air conditioned air to be pumped into the room, or for return air to be extracted from the room. A typical prior art fitting of this type provides a number of slots on either side of the fitting. For example, a typical prior art fitting of just over a meter’s length may have three bridges defining four slots on either side of the fitting, with the bridges being required to help maintain overall structural rigidity.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome, or substantially ameliorate, one or more of the disadvantages of the prior art, or to provide a useful alternative.

In one aspect of the present invention there is provided an electrical light fitting including an elongate body configured for installation into a ceiling, the elongate body defining a lower side from which, in use, light is capable of being emitted, the elongate body defining at least one air flow channel extending between a lower end and an upper end such that, in use, the lower end is in fluid communication with air below the ceiling and the upper

2019101102 24 Sep 2019 end is disposed above the ceiling, the lower end being either visually obscured, or minimally visible, when viewed from a vantage point below and spaced from the lower side.

Preferably, the lower end is shaped as a longitudinal slot which, in use, is substantially orthogonal to the ceiling.

In one embodiment the air flow channel is defined by an upper member having an Lshaped cross section and a lower member having a complementary L-shaped cross section. In this embodiment the body includes a chassis housing hardware capable of emitting light and the body further includes a trim attachable to the chassis. In this embodiment the upper member is defined by the chassis and the lower member is defined by the trim.

Preferably the longitudinal slot extends continuously for substantially a length of the elongate body.

The features and advantages of the present invention will become further apparent from the following detailed description of preferred embodiments, provided by way of example only, together with the accompanying drawings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Figure 1 is a lower perspective view of an embodiment of the invention;

Figure 2 is an upper perspective view of the embodiment;

Figure 3 is a plan view of the embodiment;

Figure 4 is a left side view of the embodiment, with the right side view being identical;

Figure 5 is a front view of the embodiment, with the rear view being identical;

Figure 6 is a bottom view of the embodiment;

Figure 7 is an exploded view of the embodiment;

Figure 8 is a schematic transverse cross sectional view of the embodiment showing airflow along the air flow channel; and

Figure 9 is a transverse cross sectional view of the embodiment.

2019101102 24 Sep 2019

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The illustrated embodiment of the electrical light fitting 1 includes an elongate body 2 configured for installation into a ceiling in a known manner. For example, some embodiments of the light fittings, known as troffers, are rectangular light fixtures that fit into the modular dropped ceiling grids that form the suspended or T-bar ceilings often found in offices and the like.

The illustrated embodiment is over a meter long and, more specifically, is 1191 mm long. This embodiments is also 293 mm wide and 105.9 mm high. It will be appreciated that the dimensions of other embodiments will vary from these figures. That is, other embodiments may be longer or shorter and may have widths of approximately 400 mm or 600 mm, for example.

The body 2 of the preferred embodiment is made from panels of sheet metal that are cut, folded and otherwise shaped to form the required components. As best illustrated in figure 7, the main components of the elongate body 2 are an upper gear tray 3, an intermediate chassis 4 and a lower trim 5. The upper gear tray 3 and the lower trim 5 are each attachable to the chassis 4 by fasteners, such as screws, extending through the holes 18 and 19 provided at either end of the fitting 1. In alternative embodiments, the upper gear tray 3 and the lower trim 5 are each attachable to the chassis 4 by other means, such as rivetting, welding, etc.

Some of the electrical components required for operation of the electrical light are disposed on the gear tray, such as the ballast 6 as shown in figure 9, for example.

Light-emitting hardware, such as a light emitting diode (LED) board 7, is centrally mounted upon the lower side of the upper horizontal member 8 of the chassis 4. During operation, light is emitted from the LED’s so as to shine towards the lower side 10 of the elongate body 2.

It will be appreciated by those skilled in the art that other types of light-emitting hardware, such as fluorescent tubes, compact fluorescent lamps, incandescent lamps, halogen lamps, metal halide lamps, neon lamps, low pressure sodium lamps and high intensity

2019101102 24 Sep 2019 discharge lamps, for example, may be housed within the chassis in the place of, or in combination with, the LED’s of the illustrated embodiment.

A curved transparent or opaque cover 9 houses the light emitting hardware for protection, light diffusion and/or aesthetic reasons.

The elongate body 2 defines at least one, and in the illustrated embodiment a pair, of air flow channels 11. A typical air flow path 12 through one of the channels 11 is shown in figure 8. The air flow channels 11 each extend between a lower end 13 and an upper end 14 such that, in use, the lower end 13 is in fluid communication with air below the ceiling and the upper end is disposed above the ceiling. This is required for air conditioning purposes to allow air to flow through the air flow channels 11 from the room below the ceiling to the cavity above the ceiling so that air may be returned to the air conditioning system. Alternatively, conditioned air may flow through the air flow channels 11 from air conditioning ducting located in the cavity above the ceiling so as to be vented into the room below the ceiling.

The lower ends 13 of the air flow channels 11 are either visually obscured, or minimally visible, when viewed from a vantage point below and spaced from the lower side (i.e. when viewed from a typical person’s vantage point within a room having a ceiling in which the light fitting has been installed). In the preferred embodiment the lower ends 13 of the air flow channels 11, which are shaped as longitudinal slots 15, are substantially orthogonal to the ceiling. Hence, if one of these slots 15 is viewed from directly below, then it is effectively completely visually obscured. If viewed from slightly to one side of directly below a slot 15, then only a small proportion of that slot 15 is visible. This contrasts with the prior art in which the slots are parallel with the ceiling and hence those prior art slots are highly visible when viewed from such a typical vantage point. The visual obscuring or minimising of the slots 15 of the present invention is generally considered to improve the aesthetics of the light fitting 1.

The upper sides of each of the air flow channels 11 are defined by the chassis. More specifically, they are defined by a pair of upper members 16 that respectively form the left and right hand extremities of the chassis 4. These upper members 16 each have an L-shaped cross section, as best shown in figures 7, 8 and 9.

2019101102 24 Sep 2019

The lower sides of each of the air flow channels 11 are defined by lower members 17 having an L-shaped cross section that is complementary to the L-shaped cross section of the upper members 16. That is, the L-shaped cross section of the upper members 16 is smaller than that of the lower members 17, which allows the upper members 16 to be positioned within the horizontal and vertical limits defined by the lower members 17, as best shown in figure 8. The lower members 17 are defined by the left and right hand sides of the trim 5, as best shown in figure 7.

It has been appreciated by the inventor that the L-shaped profiles of the upper and lower members 16 and 17 provides improved strength characteristics as compared to the prior art slots that are simply formed within a flat portion of sheet metal. These improved strength characteristics allow for the prior art bridges to be dispensed with. In other words, as can be seen for example in figure 1, each of the longitudinal slots 15 extends continuously for substantially the length of the elongate body 2. This pair of longitudinal slots 15 is not interrupted by any of the bridges that are found on the prior art light fittings. Hence, it has been appreciated by the inventor of the present application that the lack of these bridges in the present invention allows for some additional design flexibility as compared to the prior art. For example, the lack of the bridges may be used to increase the total area of the slots 15 so as to improve the air flow characteristics as compared to the prior art. Alternatively, the lack of the bridges may give the designer the freedom to make the slots narrower than the prior art slots whilst still allowing for the same total air flow capacity. The width of each of the slots 15 in the illustrated embodiment is 15 mm, although it will be appreciated that other widths may be used, such as 10 mm or 20 mm, for example.

An additional advantage associated with the lack of the bridges is the removal of one potential source of turbulence in the air flow stream, which has the potential to further improve the flow characteristics through the air flow channels 11.

While a number of preferred embodiments have been described, it will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (5)

1. An electrical light fitting including an elongate body configured for installation into a ceiling, the elongate body defining a lower side from which, in use, light is capable of being emitted, the elongate body defining at least one air flow channel extending between a lower end and an upper end such that, in use, the lower end is in fluid communication with air below the ceiling and the upper end is disposed above the ceiling, the lower end being either visually obscured, or minimally visible, when viewed from a vantage point below and spaced from the lower side.

2. An electrical light fitting according to claim 1 wherein the lower end is shaped as a longitudinal slot which, in use, is substantially orthogonal to the ceiling.

3. An electrical light fitting according to claim 1 or 2 wherein the air flow channel is defined by an upper member having an L-shaped cross section and a lower member having a complementary L-shaped cross section.

4. An electrical light fitting according to claim 3 wherein the body includes a chassis housing hardware capable of emitting light and the body further includes a trim attachable to the chassis and wherein the upper member is defined by the chassis and wherein the lower member is defined by the trim.

5. An electrical light fitting according to any one of claims 2 to 4 wherein the longitudinal slot extends continuously for substantially a length of the elongate body.