GB2617131A

GB2617131A - A plenum device and a plenum system

Info

Publication number: GB2617131A
Application number: GB2204555.3A
Authority: GB
Inventors: Ward Robert; Weston Thomas
Original assignee: Lumi Plugin Ltd
Current assignee: Lumi Plugin Ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2023-10-04
Anticipated expiration: 2042-03-30
Also published as: WO2023186989A1; GB202204555D0; GB2617131B

Abstract

A plenum device and a plenum system; the device 10 comprises a body 12 having a first opening 18 at a first end 20 and a second opening 22 at a second end 24 and a curved air flow channel (26, fig 1B) therebetween. The second opening has an aperture 28 and an adjustment mechanism 16 at the second opening for varying the size of the aperture. A fixing bracket 14 coupled to the exterior of the body secures the plenum device to a ceiling void space, and the bracket includes an adjustable engagement mechanism 17 for securing and moving the bracket relative to the body in one of a plurality of height positions. The first end is coupled to an air duct of a ventilation system and the second end is coupled to an inlet/outlet port (100). The plenum system comprises the plenum device and a modular lighting fixture having an inlet / outlet portion. The engagement mechanism may comprise a rack (36, fig 1C) on the body and latch (38) on the bracket. The aperture adjustment mechanism may comprise a mechanical iris having a plurality of blades (28a, fig 6) moveable by rotation of an adjustment ring (30).

Description

A Plenum Device And A Plenum System The present invention relates to a plenum device and a plenum system.

In embodiments, the present invention relates to a plenum device and a plenum system for use in a ceiling void space.

A room of any kind of building, such as a house with one or more storeys or an office building with a plurality of storeys, generally has an interior space defined by the floor, the ceiling, and walls. Typically, rooms in such buildings have false ceilings. To put in another way, the ceiling in such spaces is usually comprised of a structural part (i.e. the real ceiling) and panels provided on a support structure or other forms of partitions below the structural part, with a space in between. This space, known as the ceiling void space, allows electrical wiring, plumbing and fire suppression piping, and other fittings and fixtures necessary for the room to function properly to be installed and hidden out of sight. For example, in buildings that are ventilated and/or air-conditioned through a centralised system, air ducts are necessary in order to deliver controlled air flow to and from the interior space. Installing air ducts in an exposed manner is aesthetically and practically undesirable, as exposed air ducts are unsightly and are very rarely fire rated. It is therefore common practice to install air ducts in the ceiling void space using plenums as connecting devices to connect the air ducts to air inlet/outlet ports.

Plenums are usually elbow bends and are typically formed from a small section of duct or pipe, moulded into a right-angle. To accommodate different dimensions of ceiling void spaces of different rooms and buildings, commercially available plenums are usually manufactured with an excess length to allow an installer to cut the elbow bend downpipe to the desired size when installing. Precise measurements of the ceiling void space and precise cutting of the plenum elbow bend downpipe are necessary to achieve a secure fit with a satisfactory airtight finish.

Figure 12 shows a typical plenum elbow bend 1 that is commercially available. The plenum elbow bend 1 comprises a tubular section 2. The tubular section 2 is usually an L shape (as depicted), has a first end 4 configured to connect to ducts or pipes in the ceiling void space, and has a second end 6 configured to connect to an inlet/outlet port in a ceiling panel. Indicators 8 are provided on the exterior near the second end 6 -2 -and function as aids to guide the installer to cut the plenum elbow bend 1 to the desired size. One main disadvantage of such an arrangement is that once the downpipe of the plenum elbow bend 1 is installed into the ceiling void space, it is very difficult and impractical to make adjustments to the plenum elbow bend 1. Furthermore, the length of the downpipe of the plenum elbow bend 1 can only ever be shortened and cannot be extended. It is therefore desirable to provide an improved plenum device that could address these shortcomings.

According to an aspect of the present invention, there is provided a plenum device, comprising a body section having a first opening at a first end and a second opening at a second end defining a curved air flow channel therebetween through the body section, the second opening having an aperture; a fixing bracket moveably coupled to the exterior of the body section and configured to secure the plenum device to a ceiling void space; and an adjustment mechanism arranged at the second opening of the body section and configured to vary the size of the aperture; wherein the first end is configured to be coupled to an air duct of a ventilation system and the second end is configured to be coupled to an inlet/outlet port; and wherein the fixing bracket is configured to be moveable relative to the body section between a plurality of positions and includes an adjustable engagement mechanism arranged to secure the fixing bracket in one of the plurality of positions. The plenum device of the present invention can be easily adjusted without the use of any tools for installation by virtue of the height-adjustable fixing bracket, and can be readjusted during or after installation without having to disconnect the plenum device.

In embodiments, the engagement mechanism comprises a rack provided on the body section and a latch provided on the fixing bracket. Preferably, the rack has a directionally shaped profile.

In embodiments, the air flow channel has an L shape and the fixing bracket is configured to be moveable in line with the L shape.

In embodiments, the aperture comprises a mechanical iris with a plurality of blades. Preferably, the adjustment mechanism comprises an adjustment ring disposed about the second opening and mechanically coupled to the plurality of blades, wherein the adjustment mechanism is configured such that rotation of the adjustment ring about the second opening causes the mechanical iris to open and close. -3 -

In embodiments, the adjustment ring includes a plurality of circumferentially disposed teeth, configured to engage a plurality of complementary teeth of an adjustment key in an axial direction.

In embodiments, the adjustment ring includes a plurality of circumferentially disposed index markers corresponding to respective plurality of positions in which the iris is opened to respective predetermined sizes, wherein the adjustment mechanism includes a detent resiliently biased towards engaging one of the index markers to hold the adjustment ring from free rotation. In some of these embodiments, the adjustment ring includes a plurality of circumferentially disposed index markers corresponding to twenty one respective plurality of positions. In some of these embodiments, the detent is spring loaded.

In embodiments, the blades are configured to retract to retracted position in which the second opening is not obstructed by the blades. In embodiments, the fixing bracket includes a mounting mechanism having threaded holes to enable the plenum device to be screw-mounted. In embodiments, the plenum device further comprises a guide loop provided in alignment with the engagement mechanism. In embodiments, the guide loop is provided on the exterior of the body section proximal to the second end.

In embodiments, the plenum device further comprises an upper housing part and a lower housing part forming a housing structure, wherein the aperture and the adjustment mechanism are housed within the housing structure.

According to another aspect of the present invention, there is provided a plenum system comprising a plenum device and a modular lighting fixture; wherein the modular lighting fixture includes an inlet/outlet portion; wherein the plenum device comprises a body section having a first opening at a first end and a second opening at a second end defining a curved air flow channel therebetween through the body section, the second opening having an aperture; a fixing bracket moveably coupled to the exterior of the body section and configured to secure the plenum device to a ceiling void space; and an adjustment mechanism arranged at the second opening of the body section and configured to vary the size of the aperture; wherein the first end is configured to be coupled to an air duct of a ventilation system and the second end is configured to be coupled to the inlet/outlet portion of the modular lighting fixture; and wherein the fixing -4 -bracket is configured to be moveable relative to the body section between a plurality of positions and includes an adjustable engagement mechanism arranged to secure the fixing bracket in one of the plurality of positions.

Embodiments of the present invention will hereinafter be described by way of examples, with references to the accompanying drawings, in which: Figure la shows a perspective view of a plenum device; Figure lb shows a cross-section view of a plenum device; Figure lc shows an exploded view of a plenum device together with an inlet/outlet port; Figure 2 shows a perspective view of a fixing bracket of a plenum device; Figure 3 shows another perspective view of a fixing bracket of a plenum device; Figure 4 shows a perspective view of a body section of a plenum device; Figure 5 shows another perspective view of a body section of a plenum device; Figure 6 shows a perspective view of a mechanical iris aperture of a plenum device; Figure 7 shows a perspective view of an adjustment mechanism of a plenum device; Figure 8 shows a perspective view of housing parts together with a mechanical iris aperture and an adjustment mechanism of a plenum device; Figure 9 shows an exploded view of a plenum system; Figures 10a and 10b show perspective views of an outlet plugin of a plenum system; Figures lla and llb show perspective views of an inlet plugin of a plenum system; and

Figure 12 shows a prior art plenum elbow bend. -s -

Embodiments of the present invention relates to a plenum device for connecting a duct or a pipe of a ventilation system to an inlet/outlet port. In particular, the plenum device of the present invention is configured to connect ducts and pipes of a ventilation system (such as a mechanical ventilation with heat recovery system) in the ceiling void space above a room to inlet/outlet ports installed in ceiling panels. In some particular embodiments, the inlet/outlet portion is a functional part of a modular lighting fixture.

The plenum device 10 of the present invention, including the embodiment depicted in figures 1a to 1c, generally includes a body section 12, a fixing bracket 14, and an adjustment mechanism 16. The body section 12 has a first opening 18 at a first end 20 and a second opening 22 at a second end 24. An air flow channel 26 is defined between the first opening 18 and the second opening 22, and extends through the body section 12. In some embodiments, such as that shown in figures la to 1c, the first end 20 of the body section 12 is configured to be connected to a duct or pipe of a ventilation system. This connection to ducts or pipes of a ventilation system may be by any suitable means known to the skilled person, including any standardized connections known in the relevant industries. The second end 24 is configured to be connected to an inlet/outlet port 100, which may be provided in a ceiling panel such as in the embodiment shown in figures 1a to lc, in particular in the exploded view of figure 1c. The inlet/outlet port 100 itself may simply be a passage for air flow, or it may have other flow control elements such as a valve. In embodiments, the air flow channel 26 is generally of a curved shape to direct air flow to/from the duct or pipe to which it is connected, which usually extends through the ceiling void space, from/to the inlet/outlet port 100, which is usually positioned to face the room or interior space below the ceiling panel.

In embodiments such as that shown in figures la to 1c, an aperture 28 is provided at the second opening 22. The size of the aperture 28 is adjustable to enable the size of the second opening 22 to be varied in order to regulate the air flow through the channel 26 when the plenum device 10 is installed. The adjustment mechanism 16 is provided, mechanically coupled to the aperture 28, to facilitate the adjustment of the aperture 28. In embodiments, the aperture 28 is a mechanical iris with a plurality of blades, similar to apertures found in camera lenses. In one embodiment, the iris comprises eight blades. In another embodiment, the iris comprises fourteen blades. The adjustment mechanism 16 may be coupled to the aperture 28 by any suitable means known to the -6 -skilled person, such as via gears, levers, pivots, and any other suitable mechanical components. In embodiments such as that shown in figures la to 1c, the adjustment mechanism 16 includes an adjustment ring 30, which is disposed coaxially about the second opening 22. The adjustment ring 30 is mechanically coupled to the blades of the aperture 28 and is configured so that rotation of the adjustment ring 30, for example in a similar manner to turning a dial, causes the blades to advance and/or retract to close and/or open the aperture 28. Closing (partially or fully) and opening the aperture 28 changes the size of the second opening 22, thereby varying the amount or speed of air flow allowed through the channel 26. In some embodiments, the adjustment ring 30 includes a lock-and-key type arrangement, whereby the adjustment ring 30 is configured such that a key may be used to engage and turn/rotate the adjustment ring 30. In some embodiments, the adjustment mechanism 16 includes an index mechanism to allow the amount by which the adjustment ring 30 is rotated to be precisely controlled, such as by restricting rotation of the adjustment ring 30 to predetermined increments, thereby controlling the amount by which the size of the aperture 28 is varied.

The fixing bracket 14 of embodiments including that shown in figures la to 1c is provided on the exterior of the body section 12 to enable the plenum device 10 to be fixed in position. For example, in some embodiments, when the plenum device 10 is installed, the second end 24 is connected to an inlet/outlet port 100, which is in itself fixed to a ceiling panel, and the fixing bracket 14 is mounted to a support structure, such as a joist, the underside of the floor above, or the true/structural part of the ceiling, to secure the plenum device 10 in a stable position. The fixing bracket 14 is moveably coupled to the body section 12 and is moveable between a number of positions. The plenum device 10 may also be provided with an adjustable engagement mechanism 17 so that the fixing bracket 14 may be locked in any one of these positions to enable the dimensions of the plenum device 10 to be adjusted to suit the space into which it is to be installed. To adjust the dimensions of the plenum device 10, the engagement mechanism 17 may be released to allow the fixing bracket 14 to move (e.g. vertically up and down) relative to the body section 12. Once the desired adjustment has been made, the engagement mechanism 17 may be actuated again to lock the fixing bracket 14 in the desired position. In some embodiments, the engagement mechanism 17 may be spring loaded push-to-release mechanism. -7 -

To install the plenum device 10, the space into which the plenum device 10 is to be installed may be measured and the fixing bracket 14 may be adjusted and locked into a desired position in the way set out above. During installation, the position of the fixing bracket 14 may be further adjusted if the initial measurement was incorrect or inaccurate, or if the final ceiling height differs from initial plans. This is advantageous over conventional elbow bends such as the plenum elbow bend 1 shown in figure 12 as the plenum device 10 does not require any excess length to be cut off in order for the size of the plenum device 10 to be adjusted. Furthermore, it is advantageous in that the dimensions of the plenum device 10 can be adjusted more precisely by adjusting the fixing bracket 14 and it can be easily readjusted.

In particular embodiments of the plenum device 10, including that shown in figures la to 1c, the body section 12 is formed into a shape to provide a curved air flow channel 26. More particularly, the air flow channel 26 of some of these embodiments has a 90 degrees transition (i.e. an "r shape with a constant radius of curvature) to redirect air flow from a horizontal duct or pipe connected to the first end 20 downwards to an inlet/outlet port 100 connected to the second end 24. In some embodiments, the air flow channel 26 is mainly circular in cross-section, as are the first opening 18 and the second opening 22. The cross-section may be a constant shape along the length through the air flow channel 26 or it may vary. For example, the cross-section at portions near the first end 20 and near the second end 24 may be larger or smaller than the cross-section at other portions of the air flow channel 26. It will however be appreciated by the skilled person that the air flow channel 26 may have any other suitable curvature and cross-section shape. In some embodiments, the plenum device 10 further includes a seal 31 as shown in figure 1c, provided at or proximal to the second end 24. The seal 31 may be formed from any suitable material, such as rubber or plastic, and sits between the plenum device 10 and the inlet/outlet port 100 when the plenum device 100 is installed to provide a sealed connection. This arrangement minimises or prevents air leakage and facilitates efficient and proper functioning of the ventilation system. As shown in figure 1c, the seal 31 is a sleeve with ridges on the radially inward side. The ridges are axially spaced to allow for a margin of movement between the plenum device 10 and the inlet/outlet port 100 whilst maintaining the sealed connection. As shown in figure 1c, the seal 31 is provided with three ridges. However, it will be appreciated by the skilled person that any other number of ridges may also be suitable. It will also be appreciated by the skilled person that the seal 31 may be any other suitable shape, such as a ring. -8 -

Figures 2 to 7 show the components of embodiments of the plenum device 10 in more detail. For ease of reference only, the first end 20 is referred to as the front, with the first opening 18 facing forwards, and the second end 24 is referred to as being at the bottom of the plenum device 10, with the second opening 22 being oriented to face downwards. As shown in figures 2 to 5, guide rails 32 are provided on the exterior of the body section 12 and complimentary guide channels 34 are provided on the fixing bracket 14 to couple to the guide rails 32 of the body section 12. In other embodiments, other forms of arrangement may be provided to enable guided movement of the fixing bracket 14 relative to the body section 12. For example, the body section 12 may be provided with one or more guide studs and the fixing bracket 14 may be provided with one or more guide grooves along which the guide studs may slide.

Figures 2 and 3 show details of the fixing bracket 14 of an embodiment of the plenum device 10, and figures 4 and 5 show details of the body section 12 of an embodiment of the plenum device 10. As shown, the fixing bracket 14 has a cap shape that is configured to sit over the body section 12 when the plenum device 10 is assembled as shown in figures la and lb. The guide rails 32 on the body section 12 shown in figures 4 and 5 are configured to slide along the guide channels 34 on the fixing bracket 14 shown in figures 2 and 3. This arrangement enables the fixing bracket 14 to slidingly move relative to the body section 12. The fixing bracket 14 is configured to move in an up-down direction, as indicated by the arrow shown in figure 5, towards and away from the second end 24 of the body section 12, thereby enabling the dimensions of the plenum device 10 to be varied. In other embodiments that the skilled person would recognise, the guide rails 32 and guide channels 34 may be arranged in other suitable ways. In some embodiments, the guide channels 34 may be defined on the fixing bracket 14 by a formation having a "C" shaped cross-section and the guide rails 32 on the body section 12 may have a "T shaped cross-section. This arrangement allows the fixing bracket 14 to slide against the body section 12 in a secure manner and helps the guide rails 32 to stay in the guide channels 34. It will also be appreciated that in some embodiments, other suitable number of guide channel(s) and guide rail(s) may be provided.

Details of the engagement mechanism 17 to enable the fixing bracket 14 to be adjusted between a plurality of positions relative to the body section 12 and to be secured in any -9 -one of those positions is shown across figures 2 to 5. In embodiments, the engagement mechanism 17 comprises a latch or catch arrangement, with a rack 36 provided on the exterior of the body section 12 and a latch 38 provided on the fixing bracket 14. This arrangement allows the fixing bracket 14 to be adjusted to a certain position relative to the body section 12 and be secured in that position. In some embodiments, the latch 38 is spring loaded in a press-to-release arrangement and is configured to be biased towards the rack 36, thereby securing the fixing bracket 14 in position relative to the body section 12 without additional fixtures. In some embodiments, the profile of the rack 36 may be directionally shaped to allow the fixing bracket 14 to slide in one direction without having to release the latch 38, whilst requiring the spring-biased latch 38 to be released in order to release the fixing bracket 14 for adjustment in the other direction. An advantage of such a directional arrangement is that the fixing bracket 14 may be extended to a desired position without the need or any tools, whilst being locked in position during installation when the plenum device 10 is usually subjected to compression forces when being pushed into the ceiling void space or when the inlet/outlet port 100 is pushed against it. In some embodiments, the proportions of the plenum device 10 and the arrangement of the engagement mechanism 17 are selected to allow the plenum device 10 to be installed (i.e. connected to a ventilation system at the first end 20 and to an inlet/outlet port 100 at the second end 24) in a ceiling void space that is 195mm deep when the plenum device 10 is fully retracted (i.e. with the fixing bracket 14 sitting as close as possible to the body section 12) and 300mm when the plenum device 10 is fully extended (i.e. with the fixing bracket 14 sitting as far to the body section 12 as the engagement mechanism 17 would allow).

As shown in figures 2 and 3, a mounting mechanism 40 by which the assembled plenum device 10 is mounted to a support structure is provided on the fixing bracket 14. The mounting mechanism 40 as shown comprising threaded holes provided at the top of the fixing bracket 14 to enable the fixing bracket 14 to be mounted with screws.

For example, the threaded holes may be positioned to allow the fixing bracket 14 to be mounted to a flat surface in the ceiling void space of a ceiling. In other embodiments, the mounting mechanism 40 may include other suitable means known to the skilled person to enable the fixing bracket 14 to be mounted to a support structure. It will also be appreciated by the skilled person that the mounting mechanism 40 may also be provided anywhere else that is suitable on the fixing bracket 14.

-10 -Figure 6 shows details of the aperture 28 of an embodiment of the plenum device 10. In this embodiment, the aperture 28 is a mechanical iris similar to a typical camera lens aperture and comprises a plurality of blades 28a arranged to partially overlap each other. The blades 28a are arranged so as to be able to move collectively between a retracted configuration to a closed configuration by actuation of the adjustment mechanism 16. In the retracted configuration, the blades 28a are positioned around the periphery of the second opening 22 so as to not obstruct air flow through the second opening 22. In the closed configuration, the blades 28a are positioned in an overlapping manner to block the second opening 22 to prevent air flow. Actuation of the adjustment mechanism 16 causes the blades 28a to move between the retracted configuration and the closed configuration. In the process, the size of the opening formed by the blades 28a is varied. Varying the size of the aperture 28 when the plenum device 10 is assembled and installed enables the rate of air flow through the plenum device 10 to be regulated; a larger aperture 28 allows more air flow and a smaller aperture 28 allows less air flow.

Figure 7 shows details of the adjustment mechanism 16 of an embodiment of the plenum device 10. In this embodiment, the adjustment mechanism 16 includes an adjustment ring 30 as described already that is mechanically coupled to the blades 28a of the aperture 28. The adjustment ring 30 is substantially circular in shape and index markers 30a are disposed circumferentially on the radially outward side of the adjustment ring 30. As shown, the adjustment ring 30 of this embodiment is provided with two clusters of index markers 30a provided on diametrically opposing sections of the adjustment ring 30. In some embodiments, only one cluster of index markers 30a is provided. In some other embodiments, more than two clusters are provided. The index markers 30a may be grooves, notches, indentations, or any other suitable shape with a recess, and a cluster of index markers 30a includes a plurality of closely spaced index markers 30a. The adjustment mechanism 16 also includes one or more resiliently biased detents 42, held independently of the adjustment ring 30 and biased towards engaging one of the index markers 30a. In the embodiment shown in figure 7, each cluster of index markers 30a is provided with a corresponding detent 42. In some embodiments, only one detent 42 may be provided irrespective of the number of clusters of index markers 30a. As shown in figure 1c, the adjustment ring 30 is arranged in a position that is coaxial with the aperture 28 within the assembled plenum device 10. The adjustment ring 30 is configured to have a circular central opening space that is substantially the same size as the second opening 22. The resilient biasing of the detent 42 and the shape of the index markers 30a are tuned (such as by selected a suitable depth for the grooves, notches, indentations, etc. of the index markers 30a, or by selecting a sufficiently stiff spring bias for the detent 42) so that engagement of the detent 42 with one of the index markers 30a prevents the adjustment ring 30 from freely rotating, whilst allowing the adjustment ring 30 to be rotated by an application of a sufficiently large force by a user. Such an arrangement allows the adjustment ring 30 to be rotated by a small amount corresponding to the spacing between adjacent index markers 30a and held in that position, thereby enabling the size of the aperture 28 to be adjusted by a precise amount. In some embodiments, the index markers 30a are arranged around the adjustment ring 30 to allow the aperture 28 to be adjusted between 20mm in diameter and 59.5mm in diameter in eight equal steps. In some other embodiments, the index markers 30a are arranged to enable this adjustment in twenty one equal steps.

As shown in figure 7, the adjustment ring 30 of this embodiment also has circumferentially spaced teeth 30b disposed at the radially inward side towards the central opening space of the adjustment ring 30. The teeth 30b as shown in the embodiment of figure 7 are evenly spaced. However, it will be appreciated by the skilled person that the teeth 30b may be spaced in other suitable arrangements and need not be evenly spaced or provided all the way around the radially inward side of the adjustment ring 30. The teeth 30b of the adjustment ring 30 are arranged to interlink with complimentarily configured teeth on a "key" such that turning of the "key" turns the adjustment ring 30. This arrangement enables the size of the aperture 28 to be adjusted after the plenum device 10 has been installed. For example, after the plenum device 10 has been installed, there may be no practical way for a user to reach the adjustment mechanism 16 to adjust the size of the aperture 28 without dismantling the ceiling into which the plenum device 10 is installed and disconnecting the plenum device 10 altogether. With the arrangement shown in figure 7, a user may use a key through the inlet/outlet port to which the plenum device 10 is connected to reach and actuate the adjustment mechanism 16 provided that the key has complimentarily arranged teeth to engage the teeth 30b of the adjustment ring 30. As an alternative to the teeth 30b arrangement shown in figure 7, other suitable surface feature apparent to the skilled person may be provided on the radially inward side of the adjustment ring 30 to allow a key or tool with complementary surface features to reach and actuate the adjustment ring 30 through an inlet/outlet port to which the plenum device 10 is connected.

-12 -In some embodiments, the aperture 28 and the adjustment mechanism 16 may be provided within the body section 12. In some other embodiments, the aperture 28 and the adjustment mechanism 16 may be provided in separate housing structures, or together in a single housing structure, coupled to the body section 12. For example, figure 8 shows an embodiment in which the aperture 28 and the adjustment mechanism 16 are provided in a housing made up of an upper housing part 50 and a lower housing part 52. The upper housing part 50 has a connector end 50a that is configured to couple to the second end 24 of the body section 12. The lower housing part 52 is configured to be connected to an inlet/outlet port 100. In this embodiment, the seal 31 as shown in figure lc may be provided in the lower housing part 52. In the embodiment shown in figure 8, the upper housing part 50 and the lower housing part 52 are configured to be fastened together with bolts 54. It will however be appreciated that other means of fastening the upper housing part 50 and the lower housing part 52 together may also be suitable. In some embodiments, the lower housing part 52 is further provided with a latch (not shown) that holds the adjustment ring 30 of the adjustment mechanism 16 vertically in place. This prevents the adjustment ring 30 from moving axially and contacting the aperture 28 unintentionally, which may interfere with the functioning of the aperture 28.

A loop 56 is provided as shown in figure 8 to allow a user to guide an implement to actuate the engagement mechanism 17 to adjust the plenum device 10 after the plenum device 10 has been installed. The loop 56 is positioned near the second end 24 of the body section 12 and is vertically aligned with the engagement mechanism 17.

In the embodiment shown in figure 8, the loop 56 is provided on the exterior of the lower housing part 52 of the housing that houses the aperture 28 and the adjustment mechanism 16. In other embodiments where the aperture 28 and the adjustment mechanism 16 are housed within the body section12, the loop 56 may be provided on the exterior of the body section 12 itself. The loop 56 aids a user to guide a long tool, such as a rod or a screwdriver, to reach the engagement mechanism 17 even when the plenum device 10 is installed (i.e. where there is limited space to extend a hand to reach the engagement mechanism 17) without having to dismantle the installation.

As shown in figure lc, the inlet/outlet port 100 has a generally tubular portion and a second portion provided circumferentially at one end of the main portion, extending radially outwards from the main portion in a similar arrangement to a flange so as to -13 -give the inlet/outlet port a top hat shaped silhouette. The inlet/outlet port is generally configured to be received in a recess or opening in the ceiling panel. In some embodiments, the plenum device 10 may be configured to connect to a modular lighting fixture that incorporates an inlet/outlet portion. For example, the modular lighting fixture may have a similar top hat shaped silhouette as the inlet/outlet port 100, with lighting means provided in the radially outwardly extending portion and the central portion functioning as an inlet/outlet for air flow. In some embodiments, the connection at the second end 24 (or at the lower housing part 52) is 125mm in diameter. In some other embodiments, the connection is 59mm in diameter. Using the plenum device 10 with such inlet/outlet ports or modular lighting fixtures has the advantage that the dimensions of the plenum device 10 may be finely adjusted by adjusting the fixing bracket 14. This enables the whole installation to be finely adjusted to ensure the inlet/outlet port or the modular lighting fixture is installed correctly and sits flush with the ceiling.

Referring to figure 9, a plenum system 1000 according to embodiments of the present invention includes a plenum device 10 as described hereinabove and an air inlet/outlet port 100 or a modular lighting fixture (not shown). In embodiments that include a modular lighting fixture, the modular lighting fixture comprises light emitting means that are generally arranged in a configuration that allows light emitted from the light emitting means to reach the room in which the modular lighting fixture is installed. The modular lighting fixture also includes a portion that functions as an inlet/outlet that allows air flow from the room in which the modular lighting fixture is installed to the plenum device 10 that is connected thereto. In embodiments, the inlet/outlet portion of the modular lighting fixture is defined by an air flow passage that extends through the modular lighting fixture. The modular lighting fixture is generally configured to be received in a recess or opening in a ceiling panel and has means as described hereinabove to connect to the plenum device 10 to allow air to flow from/to the room in which the modular lighting fixture is installed, through the inlet/outlet portion to the air flow channel 26 of the plenum device 10, and beyond.

In some embodiments, as shown in figure 9, the plenum system 1000 further includes variations of a plugin 200a, 200b to facilitate air flow through the plenum system 1000. The plugin 200a, 200b is configured to be inserted into the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture at the side facing the room/space in a removable manner. One variation of the plugin is an outlet plugin 200a and assists in -14 -air flow out of the plenum system 1000 into the room/space in which the plenum system 1000 is installed. Another variation of the plugin is an inlet plugin 200b and assists in air flow out of the room/space in which the plenum system 1000 is installed and into the plenum system 1000.

As shown in figures 10a and 10b, the outlet variation of the plugin 200a includes a main body 202 and a cap 204. The main body 202 is provided with wings 206 that extend outwardly. The wings 206 are configured as attachment means to secure the plugin 200a to the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture and at the same time as means to provide directional control to air flowing out into the room/space. In an embodiment, the interior of the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture is provided with a circumferential groove (not shown) and the wings 206 are formed from a resiliently deformable material such that the wings 206 deform and snap-fit into the groove when inserting the plugin 200a into the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture. The groove and wings 206 are configured such that a gap is provided between the plugin 200a and the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture when the plugin 200a is inserted. In some embodiments, the gap has a depth of 3mm. In other embodiments, the gap may have a depth of 5mm or 7mm.

In the embodiment shown in figures 10a and 10b, three wings 206 are provided. It will however be appreciated that any plural number of wings 206 may also be suitable.

In some embodiments, such as that shown in figures 10a and 10b, one wing 206 is provided with a larger width to provide a greater degree of air deflection. In use, the outlet plugin 200a may be rotated to allow the direction of the airflow exiting the plenum system 1000 to be controlled.

As shown in figures 11 a and 11 b, the inlet variation of the plugin 200b includes a ring-shaped body 208 and a plurality of radial members 210 provided at the interior of the ring-shaped body 208. In the embodiment shown in figures 11 a and 11 b, the inlet plugin 200b additionally has a plurality of concentric ring members 211 provided in the interior of the ring-shaped body 208 and interconnecting with the radial members 210. In the embodiment shown in figures 11 a and 11 b, eight radial members 210 and five concentric ring members 211 are provided. It will however be appreciated that any plural number of radial members 210 and any number of concentric ring members 211 -15 -may also be suitable. Indeed, some embodiments may have no concentric ring members 211. The radial members 210 and concentric ring members 211 function as a barrier against insertion or large objects into the plenum system 1000. In some embodiments, a cloth (not shown) is provided across the radial members 210 to further prevent insertion of small objects into the plenum system 1000. The inlet plugin 200b is also provided with a plurality of extruding members 212. The extruding members 212 are provided on the exterior of the inlet plugin 200b and are configured to snap-fit into the above-described groove at the interior of the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture when inserting the plugin 200b into the inlet/outlet port 100 or the inlet/outlet portion of the modular lighting fixture.

Embodiments of the present invention have been described with particular reference to the examples illustrated. However, it will be appreciated that variations and modifications may be made to the examples described within the scope of the appending claims.

Claims

-16 -Claims: 1. A plenum device (10), comprising: a body section (12) having a first opening (18) at a first end (20) and a second opening (22) at a second end (24) defining a curved air flow channel (26) therebetween through the body section (12), the second opening (22) having an aperture (28); a fixing bracket (14) moveably coupled to the exterior of the body section and configured to secure the plenum device (10) to a ceiling void space; and an adjustment mechanism (16) arranged at the second opening (22) of the body section (12) and configured to vary the size of the aperture (28); wherein the first end (20) is configured to be coupled to an air duct of a ventilation system and the second end (24) is configured to be coupled to an inlet/outlet port; and wherein the fixing bracket (14) is configured to be moveable relative to the body section (12) between a plurality of positions and includes an adjustable engagement mechanism (17) arranged to secure the fixing bracket (14) in one of the plurality of positions.
2. A plenum device as claimed in claim 1, wherein the engagement mechanism (17) comprises a rack (36) provided on the body section (12) and a latch (38) provided on the fixing bracket (14).
3. A plenum device as claimed in claim 2, wherein the rack (36) has a directionally shaped profile.
4. A plenum device as claimed in any preceding claim, wherein the air flow channel (26) has an [shaped and the fixing bracket (14) is configured to be moveable in line with the L shape.
5. A plenum device as claimed in any preceding claim, wherein the aperture (28) comprises a mechanical iris with a plurality of blades (28a).
6. A plenum device as claimed in claim 5, wherein adjustment mechanism (16) comprises an adjustment ring (30) disposed about the second opening (22) and mechanically coupled to the plurality of blades (28a), wherein the adjustment -17 -mechanism (16) is configured such that rotation of the adjustment ring (30) about the second opening (22) causes the mechanical iris to open and close.
7. A plenum device as claimed in claim 6, wherein the adjustment ring (30) includes a plurality of circumferentially disposed teeth (30b), configured to engage a plurality of complementary teeth of an adjustment key in an axial direction.
8. A plenum device as claimed in claim 6 or 7, wherein the adjustment ring (30) includes a plurality of circumferentially disposed index markers (30a) corresponding to respective plurality of positions in which the iris is opened to respective predetermined sizes, wherein the adjustment mechanism includes a detent (42) resiliently biased towards engaging one of the index markers (30a) to hold the adjustment ring (30) from free rotation
9. A plenum device as claims in claim 8, wherein the adjustment ring (30) includes a plurality of circumferentially disposed index markers (30a) corresponding to twenty-one respective plurality of positions
10. A plenum device as claimed in claim 8 or 9, wherein the detent (42) is spring 20 loaded.
11. A plenum device as claimed in any of claims 5 to 10, wherein the blades (28a) are configured to retract to retracted position in which the second opening (22) is not obstructed by the blades (28a).
12. A plenum device as claimed in any preceding claim, wherein the fixing bracket (14) includes a mounting mechanism (40) having threaded holes to enable the plenum device (10) to be screw-mounted.
13. A plenum device as claimed in any preceding claim, further comprising a guide loop (56) provided in alignment with the engagement mechanism (17).
14. A plenum device as claimed in claim 12, wherein the guide loop (56) is provided on the exterior of the body section (12) proximal to the second end (24).-18 -
15. A plenum device as claimed in any preceding claim, further comprising an upper housing part (50) and a lower housing part (52) forming a housing structure, wherein the aperture (28) and the adjustment mechanism (16) are housed within the housing structure.
16. A plenum system, comprising a plenum device (10) and an inlet/outlet port (100) or a modular lighting fixture; wherein the modular lighting fixture includes an inlet/outlet portion; wherein the plenum device (10) comprises: a body section (12) having a first opening (18) at a first end (20) and a second opening (22) at a second end (24) defining a curved air flow channel (26) therebetween through the body section (12), the second opening (22) having an aperture (28); a fixing bracket (14) moveably coupled to the exterior of the body section and configured to secure the plenum device (10) to a ceiling void space; and an adjustment mechanism (16) arranged at the second opening (22) of the body section (12) and configured to vary the size of the aperture (28); wherein the first end (20) is configured to be coupled to an air duct of a ventilation system and the second end (24) is configured to be coupled to the inlet/outlet port (100) or the inlet/outlet portion of the modular lighting fixture; and wherein the fixing bracket (14) is configured to be moveable relative to the body section (12) between a plurality of positions and includes an adjustable engagement mechanism (17) arranged to secure the fixing bracket (14) in one of the plurality of positions.
17. The system of claim 16, further comprising a removable outlet plugin (200a) configured to be removably inserted into an interior of the inlet/outlet port (100) or the inlet/outlet portion of the modular lighting fixture; the outlet plugin (200a) having a plurality outwardly extending attachment wings (206).
18. The system of claim 16, further comprising a removable inlet plugin (200b) configured to be removably inserted into an interior of the inlet/outlet port (100) or the inlet/outlet portion of the modular lighting fixture; the inlet plugin (200b) having a plurality of radial members (210) at an interior of the inlet plugin (200b) and a plurality of extruding members (212) on an exterior of the inlet plugin (200b); the extruding members (212) being configured to engage and secure the inlet plugin (200b) to an interior of the inlet/outlet port (100) or the inlet/outlet portion of the modular lighting fixture.