PRIORITY DOCUMENT

1 0011 The present application claims priority from;

Australian Provisional Patent Application No 2013902438 titled "PLENUM CHAMBER IMPROVEMENTS" filed 1 July 2013. The content of this application is hereby incorporated by reference in its entirety.

INCORPORATION BY REFERENCE

[0002] The following publications are referred to in the present application and their contents are hereby incorporated by reference in their entirety:

International Patent Application No PCT/A.U2010/OO1622 (WO 201 1/066612) titled "DUCTED HEATING, VENTILATION AND AI CONDITIONING (HVAC) COMPONENT AND SYSTEM IMPROVEMENTS" in the names of Connect Air Manufacturing . Pty Ltd and Air Diffusion Agencies Pty Ltd.

TECHNICAL FIELD

[0003] The present invention relates to heating, ventilation and/or air conditioning (HVAC) systems and in particular, to a means and method for connecting a duct to a plenum chamber for a diffuser of such a system.

BACKGROUND

[0004] HVAC systems are known for delivering and/or circulating air through a building, such as a home or office. Typically,, such systems employ a centralised air handling unit that conditions the air to achieve a desired temperature and/or humidi ty prior to delivery of this air to one or more rooms of the building by way of a network of ducts. A tan typically propels the air through the network of ducts located within a space in the ceiling or floor of the building, whereby the pre-conditioned air or supply air enters the room through an outlet or diffusei/register located in the ceiling/wall/floor of the room. The supply air is then distributed around the room in accordance with the comfort requirements of the occupants of the room.

[0005] The diffuser is typically designed to provide uniform throw and coverage of the supply air into the room so as to achieve desired air distribution. In this regard, the diffuser typically employs blades, louvers and the like, which assist in directing the supply air so as to achieve a desired flow pattern or direction as it exits therefrom. Such an arrangement acts to evenly distribute the air throughout the room without creating uncomfortable draughts or excessive noise, which may adversely affect the comfort of the occupants of the room,

[0006] To connect the diffuser to the supply ducts of the system, a plenum chamber may be employed, which is sometimes referred to in the industry as a plenum box or a cushion head box. The plenum chamber is typically in the form of a box that acts as an air buffer for introducing the supply air to the di.ffu.ser. Conventional plenum chambers are typically constructed from, sheet metal, plastic or M.D.F. They may be insulated to minimise heat loss from or gain by the suppl air received therein. The chamber typically receives the supply air through an inlet aperture in a wall thereof where the suppl duct is connected, with the diffuser bei ng typically mounted at an outlet in a botto surface of the chamber, so as to be flush with a ceiling or the like when the plenum chamber is installed for use.

[0007] Presen tly, it is industry practice to secure a duct to a plenum chamber whils in. the roof (or above the ceiling at least) using metal fixings and silicone sealants in. an attempt to effect an air-tight seal between an end of the duct and a duet collar depending from the plenum. Effecting this connectio is fiddly and time-consuming, and the roof space is generally an uncomfortable environment, in as much as it is generally a confined space, and. very hot (or very cold).

[0008] It is against tins background that the problems and difficulties associated therewith that the present invention has been developed,

[0009] Objects and advantages of the present invention will become apparent from the followin description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embod iment of the present invention is disclosed.

SUMMARY

[0010] According to a first aspect, there is provided a connection element for connecting an end of a duct to a plenum chamber for a diffuser of a heati ng, ventilation and or air conditioning (HVAC) system, the connection element comprising a body framing a through opening, the body comprising a means for engaging an edge of a plenum chamber wall opening, and a means for securing an end of a duct with respect to the body of the connection element.

[0 11] In one form, the means for securing the end of the duet with respect to the body is adapted to secure the duct directly to the connection element. In one fonn, the means may comprise any one or more of a clip, a hook, or a spigot, which fits into the end of the duct with an interference fit. [0012] In one form, the means for securing an end of a duct with respect to the body secures a duct end attachment depending from the duet, to the body.

[0 13] in one form, the duct end attachment comprises a securement means so operati vely associated with the securement means of the connection element as to effect connection of the duct end attachment to the connection clement.

[0014] in one form, the connection of the connection element to the duet end attachment is a 'snap-fit' connection.

[0015 ] A snap-fit is a mechanical joint system where part-to-part attachment is accomplished with locating and locking features that are homogenous with one or the oilier of the components being joined. Joining requires the flexible lockin features to move aside for engagement with the locator features (which are typically inflexible) on the mating part, followed by return of the locking feature toward its anginal position to accomplish the interference required to latch the components together.

[00 6] In one form, in an alternative, the connection of the connection element to the duct end attachment is a screw thread connection.

[0017 J In one form, the plenum chamber wall opening is circular, and the body of the connection element is substantially annular, or shaped like a ring, and sized to nest in. the plenum wall opening. In an alternative, the body of the connection element may have the shape of any co vex polygon, but recti linear shapes are the most likely alternati ves to a circular shape.

[001.81 In one form, the body of the connection element supports a vane in the through opening, which is pivotally movable between positions substantially normal and paiallel to the body, so that the connection dement can also serve as a damper,

[001 1 In one form, the securement means of the connection element are adapted to secure this to any one of the system of components disclosed in PCT/AU2010/001622 (WO 2011/066612).

[0020 ] In one form, the body of the connection element comprises a collar portion, which in use, locates in the plenum wall opening so as to extend from one side of the plenum wall to the other.

[0021 J In one form, the means for securing the body i the through opening comprises a perimeter flange extending outwardly from the body, an inner edge of which, in use, will rest against the inner surface of the plenum box wall. j 0022 ] In one form, the means for securing the body in the through opening comprises at least one outwardly extending locking flange for sandwiching the plenum box wall between the perimeter flange and the or each locking flange,

[0023 ] In one form, in an alternative, the -means for securing the body in the through opening comprises locking features directed outwardly from the collar to create an interference fit between the collar and the plenum chamber wall opening,

[0024 ] According to a second aspect, there is provided a plenum chamber assembly comprising a plenum chamber having a wall comprising a wall through-open tng. and a connection element for connecting an end of a duet to a plenum chamber for a diffusc of a heating, ventilation and/or air conditioning (HVAC) system, the connection element comprising a body framing the wail through opening and comprising a means for securing the body in the plenum chamber wall opening, and a means for securi ng an end of a duct with respect to the body.

[00251 According to a third aspect, there is provided a method for securing an end of a duct with respect to a plenum chamber for a diffuscr of an HVAC system, where the connection element is of the above described type, and the plenum chamber has a wall comprising a wall through-opening, the method comprising the steps of nesting the connection element in the wall through-opening and then engaging these, and the securing an end of the duct with respect to the connection element.

[0026] in one form, the method comprises the further step of securing a duct end attachment to the end of the duct, and then securing the duct end attachment to the connection element. j 002? ] A detailed descriptio of one or more embodiments of the invention is provided below along with accompanying figures that illustrate by way of example the principles of the invention. While the invention is described in connection with such embodiments, it should be understood that the invention is not limited to any embodiment. On the contrary, the scope of the invention is limited only by the appended claims and the invention encompasses numerous alternatives, modifications and equivalents. For the purpose of example, numerous specific details are set forth in the following description in order to provide a thorough understanding of the present invention,

[00281 in order to further understand the invention, preferred embodiments, will now be described. However, it will be realised that the scope of the invention is not be confined or restricted to the details of the embodiments described below. Variations and alterations that would be readily apparent to a person skilled in the art are deemed as being incorporated within the scope of the invention. BRIEF DESCRIPTION OF DRAWINGS

[0029] Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein: j 0030] Figure 1 is a perspective view of a connection element for connecting an end of a duct to a plenum chamber for a diffuser of an HVAC system;

[0031 1 Fi gure 2 is an exploded view of an HVAC assembly comprising the connection element of Figure 1;

[0032] Figure 3 is a partially assembled view of the assembly illustrated in Figure 2;

[00331 Figure 4 is an exploded view of an HVAC assembly according to a further embodiment, this assembly comprising the connection element of Figure 1;

[0034] Figure 5 is a perspective view of a plenum chamber assembly comprising a plurality of connection elements;

[0035] Figure 6 is a perspective view of a connection element comprising a vane, so as to thereby serve as a dampe also;

10036] Figure 7 is a cross-sectional view through an interface between the connection element and a plenum chamber of a first wall thickness; and

[0037] Figure 8 is a cross-sectional view through an interface between the connection clement and a plenum chamber of a second wall thickness.

[0038] In the following description, like reference characters designate like or corresponding parts throughout the Figures.

DESCRIPTION OF EMBODIMENTS

[0039] Referring now to Figures I and 2, there is shown a connection element 1 for connecting an end of a duct 2 to a le um chamber (or box) 4 for a diffuse of an HVAC system.

[0040] The connection element I. comprises a body 10 of moulded engineering thermoplastic (and preferably fire retardant) material and a annular (or ring) shape framing a through-opening A. [0041 ] The plenum box 4 comprises a wall 4A having a circular through-opening B which is sized to nest the connection element 1 .

[0042 ] The body of the connection element comprises a collar portion 10, which in use, locates in the plenum wall opening B so as to extend from one side of the plenum wall 4A to the other.

[0043 ] The body 10 of the connection element 1 further comprises an outwardly extending perimeter flange 12, an inner edge of which, in use, will rest against tire inner surface of the plenum box wall 4A.

[0044 ] Depending from the collar 10 of the connection element at positions equispaeed about the circumference thereof are outwardly extending locking flanges 14 which serve as a means for engaging the connection element 1 with an edge of a plenum wall opening B. The plenum wail opening B comprises clearance slots C sized and spaced to allow these locking flanges 14 to pass through the plenum wall 4A until these are clear of the plenum opening B.

[0045 ] In use, the act of rotating the connection element 1 from a position in which the locking flan ges 14 are aligned with the clearance slots C, to one in which the are misaligned, will cause the plenum wall 4A to become sandwiched between the locking flanges 14 and the perimeter flange 12 of the connection, element 1.

[0046 ] Referring now to Figures 7 and 8, each of the locking flanges 14 comprises an end wall 15 to limit how far the connection element 1 can be rotated with respect to the plenum wall 4 A, and an array of serrations 19 for creating some resistance to rotation of each locking flange 14 back towards its aligned position with respect to its respective clearance slot C.

[00471 Moreover, each of the locking flanges comprises two locking flange portions 1 and 17, bridged by a shoulder portion 18, where each of these locking flange portions 16 and 17 comprise serrations 19. In this way, the connection element 1 can be used with plenum boxes 4 of at least two different wail thicknesses, being 20 and 25mm in this case,

[ 0048 ] Depending from the collar 10 of the connection element t at positions equi-spaced about the circumference thereof are inwardly extending (i.e. extending into the through opening) snap-fit tabs which serve as a means for securing an end of the duct 2 with respect to the connection element 1 by securing a duet end attachment 30 (see Figure 2) depending from the duct 2, to the connection element 1.

[0049] With reference to Figure 2, it can be seen that the duct end attachment 30 has the overall shape of a short length of tubing having opposing ends. One end 32 is adapted by the incorporation of features complementary to, and for interlocking with, the snap-Fit tabs 20 of the connection element 1. The opposing end 34 diametrically tapers down toward its terminal end. Along its length, the outer surface of this tapering portion is covered in a series of ribs 36 so as to effect secure attachment of flexible (footing 2, known as ^' flex", thereto. A detailed description of the d«ct end attachment 30 can be found in

WO 2011/066612.

[0050 ] Referring now to Figure 4, where the connection element 1 is to have a length of duet 2 of differing diameter attached thereto, then an adapter fitting 40 must b fitted between the duct end attachmeiu 30 and the connection elemen t, A detailed description of the adapter (or reducer) fitting 40 can be found in WO 2011/066612.

[0051] In cases where ah flow into the plenum 4 must be throttled or controlled, the connection element comprises mounting points so that a. damper blade 50 can be pivotally mounted to the connection element 1, so that this may serve as a damper also.

[00521 A salient advantage of this in vention is that it permits quick connection of a duct with respect to a plenum box, without need for metal fixings or silicon sealants. What is more, the amount of time spent by an installer in the ceiling (or floor) spac e i s minimised, as most of the assembly can be undertaken at ground level, with only final connection being required in the ceiling space,

[0053] Throughout the specification and the claims that follow, unless the context requires otherwise, the words "comprise" and "include" and variations such as "comprising" and "including" will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

[ 0054] The reference to any prior art in this specificatio is not, and should not be taken as, an acknowledgement of any form of suggestion mat such prior art for ms part of the common general knowledge.

[0055] it will be appreciated by those skilled in the art. that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limi ted to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.