AU2019264676A1 - Acoustic louvre and assembly - Google Patents

Abstract

A screening element for a louvre assembly is disclosed. The screening element comprises an outer portion having an outer surface which, in use of the screening element, can be exposed to environmental fluids and is sloped to direct liquid on the outer surface toward a lower portion of the screening element. The screening element further comprises an inner portion having a solid portion defining a plurality of apertures, the inner and outer portions arranged to define a cavity therebetween. A sound absorbing material is disposed in the cavity, and the sound absorbing material is configured to create a sound differential between the inner and outer portions. The lower portion of the screening element defines a drainage channel to collect the liquid, and the drainage channel is open at at least one end to allow collected liquid to drain from the lower portion. )I Fig.11

Description

Acoustic louvre and assembly

Technical Field [0001] The present disclosure is generally directed to louvre screens used in architectural applications and in particular, to acoustic louvres and assemblies for commercial and industrial acoustic attenuation purposes.

Background [0002] Noise pollution is an issue which can have an adverse effect on people. In particular, noise pollution from machinery is a significant health and safety issue when people are continually exposed to unsafe levels of noise, especially over a prolonged period. The containment of noise is not limited to industrial environments such as factories and machinery plant rooms. In urban areas and densely-built environments, it is even more important to control noise given the greater amount of people in proximity. For example, a common source of noise from residential and commercial buildings is the heating, ventilation, and air conditioning (HVAC) system, which comprises mechanical means such as fans, pumps, and compressors operating over a prolonged period.

[0003] Various authorities exist to administer noise policies and guidelines. For example, in Victoria, Australia, the Environmental Protection Authority has various policies and guidelines enforcing the applicable Victorian state legislation, such as the Environment Protection Act 1970. Furthermore, the environmental performance of buildings is an increasingly common consideration in light of “green building” certification programmes such as Green Star, NABERS, and LEED.

[0004] Construction of acoustic structures around noise sources may mitigate the transmission of noise to the outside environment. Such structures may also provide some ingress protection against dust, fluid, precipitation, and debris. These structures must balance various competing factors, for example structural integrity, thermal

2019264676 15 Nov 2019 regulation, ingress protection, acoustic attenuation, and ventilation requirements. Some current acoustic structures comprise at least one or a combination of louvres or solid panels which address the aforementioned factors to varying degrees. A louvre, as described herein is intended to indicate a slat or blade as part of a set of angled slats or blades in a barrier, such as a door, screen, or window. Sets of louvres are generally spaced apart to provide for ventilation through the spaces between louvres. However, where louvres are used, air flow may cause fluid striking the louvres to sluice or spill off and be blown or sucked through the spaces between the louvres. Additionally, the size of spaces is a trade-off between ventilation and impeding the passage of sound waves therethrough. Solid panels provide a solid barrier with no spaces, gaps, or apertures through which sound waves may pass through, however this also means ventilation is heavily impeded.

[0005] It is desired to address or ameliorate one or more shortcomings or disadvantages associated with prior acoustic louvres and assemblies for acoustic attenuation purposes, or to at least provide a useful alternative thereto.

Summary [0006] Some embodiments relate to screening element for a louvre assembly, the screening element comprising:

an outer portion having an outer surface which, in use of the screening element, can be exposed to environmental fluids and is sloped to direct liquid on the outer surface toward a lower portion of the screening element;

an inner portion having a solid portion defining a plurality of apertures, the inner and outer portions arranged to define a cavity therebetween;

a sound absorbing material disposed in the cavity, the sound absorbing material configured to create a sound differential between the inner and outer portions;

wherein the lower portion of the screening element defines a drainage channel to collect the liquid, the drainage channel being open at at least one end to allow collected liquid to drain from the lower portion.

2019264676 15 Nov 2019 [0007] The lower portion may define a front face and the drainage channel may be recessed relative to the front face. The lower portion may define an inwardly angled surface which may be disposed, in use, below the front face and may be configured to cooperate with the front face to induce liquid flowing along the front face to flow toward the drainage channel. A cross-section of the lower portion may resemble an upside-down question mark or hook shape.

[0008] The drainage channel may be open at first and second opposed ends. The drainage channel may be defined by channel walls in the lower portion, and the channel walls may comprise an outer lip that may be substantially flush with the front face.

[0009] The screening element may comprise a deflector on an upper portion of the screening element, the upper portion may be disposed opposite the lower portion, and the deflector may be configured to direct the liquid towards the lower portion of the screening element.

[0010] Some embodiments relate to a louvre assembly, comprising:

a frame having at least one drain hole; and at least one screening element mounted with the frame; said screening element comprising a drainage channel, a perforated inner portion, and a sound absorbing material, the sound absorbing material configured to absorb sound waves contacting the screening element, and the frame including a drainage arrangement for directing liquid accumulated within the drainage channel to the at least one drain hole.

[0011] At least some of the sound waves may pass through the perforated inner portion to be at least partly absorbed by the sound absorbing material.

[0012] The screening element may be configured to divert the liquid contacting the screening element such that the liquid may accumulate in the drainage channel.

2019264676 15 Nov 2019 [0013] The drainage channel may be configured to cooperate with the at least one drain hole of the frame such that the liquid in the drainage channel may access the at least one drain hole through the frame.

[0014] The assembly may comprise a plurality of the screening elements. Each one of the screening elements may comprise an upper portion disposed opposite a lower portion, and the plurality may be arranged in the frame so that the lower portion of one of the plurality of screening elements may overlap with the upper portion of an adjacent one of the plurality of screening elements. The lower portion of each one of the plurality of screening elements may overlap with the upper portion of an adjacent one of the plurality of screening elements.

[0015] Some embodiments relate to a louvre assembly, comprising:

a frame having at least one drain hole; and at least one screening element of any one of the embodiments described above, the at least one screening element mounted with the frame so that the liquid collected in the drainage channel is directed to the at least one drain hole.

[0016] Some embodiments relate to a system for acoustic attenuation, comprising the assembly of any one of the embodiments described above, configured to be disposed in a wall or structure to provide acoustic attenuation of a noise source shielded therewith.

Brief Description of Drawings [0017] Fig. 1 is a perspective front view of an embodiment of an acoustic louvre assembly, comprising at least one screening element disposed in a frame.

[0018] Fig. 2 is a perspective rear view of the acoustic louvre assembly of Fig. 1.

[0019] Fig. 3 is a section view of an embodiment of an acoustic louvre system comprising the acoustic louvre assembly of Fig. 1.

[0020] Fig. 4 is a close-up detail view of part of the section view of Fig. 3.

2019264676 15 Nov 2019 [0021] Fig. 5 is a perspective view of one of the frame members of the acoustic louvre assembly of Fig. 1.

[0022] Fig. 6 is a section view of the frame member of Fig. 5.

[0023] Fig. 7 is a perspective view of a friction-based connector used to join the frame members of the acoustic louvre assembly of Fig. 1.

[0024] Fig. 8 is a partial cutaway, perspective view of the acoustic louvre assembly of Fig. 1, showing the connection of the frame members using the connector of Fig. 7.

[0025] Fig. 9 is a perspective view of a screening element according to some embodiments.

[0026] Fig. 10 is a cross-section view of the screening element of Fig. 9.

[0027] Fig. 11 is a cross-section view of the acoustic louvre system comprising the acoustic louvre assembly, wherein the acoustic louvre assembly comprises a plurality of another embodiment of the screening element.

[0028] Fig. 12 is a close-up detail view of part of the view of Fig. 11.

[0029] Fig. 13 is a cross-section view of a screening element according to further embodiments.

Detailed Description [0030] Described embodiments relate generally to louvres and assemblies for architectural applications, and in particular, for commercial and industrial acoustic attenuation purposes. For example, some embodiments relate to an assembly comprising at least one screening element disposed in a frame, wherein each screening element has acoustic attenuation qualities. The screening element comprises a louvre. Assemblies may be installed as part of a structure to substantially enclose noise sources

2019264676 15 Nov 2019 on commercial and industrial sites to mitigate noise pollution while providing ventilation through the enclosure.

[0031] In the field of acoustic engineering, the transmission of sound waves (and specifically, undesirable sounds such as noise) may be controlled using materials to absorb, dampen, or isolate vibrations. Briefly speaking, sound travels through the air when air particles are vibrated at certain frequencies and transfer their kinetic energy into adjacent air particles. When these vibrating air particles collide, at least some of their kinetic energy is converted into another form of energy such as heat. The loss of this kinetic energy means that the vibrations eventually reduce to a level imperceptible by human hearing. This loss of kinetic energy can be expedited by placing a material in the path of the vibrating air particles so that their kinetic energy goes into vibrating the particles of the material rather than neighbouring air particles, thus reducing the transmission of the sound. The reduction in sound level transmitted through a material may be expressed as an Rw rating (sound reduction index), which may be tested in accordance with International Standard ISO 717. Materials with a higher Rw rating are better sound absorbers. In general, an increase of one unit of Rw is approximately equal to a IdB reduction in noise transmission. Materials that are effective at absorbing or insulating energy may alternatively be referred to herein as “insulation”, “soundproofing”, “sound absorbing” or “sound deadening” material. Typically, for a given volume, a softer or less-dense material is better at absorbing energy that a harder or denser material. Harder materials generally reflect rather than absorb vibrations.

[0032] Referring to Figs. 1 and 2, an embodiment of an acoustic louvre assembly 101 is shown. The assembly 101 comprises one or more screening elements 120 disposed in a frame 150, wherein each screening element has acoustic attenuation qualities. The screening element comprises a louvre 222, which may alternatively be referred to as a blade, louvre blade, or slat, for example.

[0033] The frame 150 comprises a plurality of elongate members configured to form a structure to support the screening elements 120. When installed in a wall 102 as part of an acoustic louvre system 100, the frame 150 has a lower portion 154 which is the

2019264676 15 Nov 2019 portion of the frame disposed closest to the ground. In the embodiment shown in Figs.

and 2, the assembly 101 is installed in a substantially vertical orientation, however it is envisaged that in other embodiments the assembly 101 may be installed in a nonvertical or angled orientation relative to the ground. A cladding piece 157 is disposed on the lower portion 154 to substantially surround the lower portion of the frame 150.

[0034] Embodiments of frame 150 may comprise varying quantities or configurations of elongate members, for example three elongate members in a triangular configuration, or four elongate members in a quadrilateral configuration, or one or more elongate members in a generally elliptical configuration such as a circle. In the embodiment shown in Figs. 1 and 2, the frame 150 comprises four elongate members 152 disposed in a rectangular configuration, wherein two of the elongate members are oriented substantially vertically, and two of the elongate members are oriented substantially horizontally. The lengths of the substantially vertical elongate members may be equal to the lengths of the substantially horizontal elongate members.

[0035] In some embodiments, at least one drain hole 158 may be defined in at least one of the elongate members 152, wherein the at least one elongate member 152 is disposed in the lower portion 154 of frame 150 so that gravity may facilitate the movement of accumulated moisture, fluid, or water towards and out of the at least one drain hole 158. The drain hole 158 may comprise a lower edge 159 defined by the lower portion 154. The cladding piece 157 is configured to substantially surround the elongate member 152 disposed in the lower portion 154, and in this way may prevent overflow of the accumulated moisture, fluid, or water.

[0036] Referring now to Figs. 3 and 4, the assembly 101 is configured to be installed in a wall or similar supporting structure 102 to form an acoustic louvre system 100. The system 100 is in use positioned between a noise source 104 emitting sound waves 105, and a receiver 106. For example, the noise source 104 may be a machine, and the receiver 106 may be a worker. The wall or structure 102 has a first or inner surface 108 which faces the noise source 104, and a second or outer surface 110 which faces the receiver 106. The wall or structure 102 may shield the noise source 104 to block or

2019264676 15 Nov 2019 deflect at least some of the sound waves 105 from the receiver 106. A plurality of walls or structures 102 may collectively partially define an internal space 103, for example a machine room where machines (which may act as the noise source 104) are situated. Figs. 3 and 4 show the system 100 configured to reduce noise escaping an enclosure, although in embodiments where other noise sources are present outside the enclosure, the system 100 is also configured to reduce noise intrusion into the enclosure.

[0037] Typically, wall or structure 102 absorbs, reflects, or obstructs at least some of the sound waves either by virtue of its material properties, construction, or a combination of both. Wall materials may include brick, concrete, or metal, either alone or in combination with an insulating or sound-deadening material such as glasswool. Construction methods may include the provision of a cavity 112 that physically separates portions of the inner and outer surfaces 108, 110 such that the air in the cavity 112 reduces the transmission of vibrations compared to the denser and harder wall material.

[0038] In the embodiment shown, the at least one screening element 120 is attached to the frame 150 by mechanical fasteners 180. The frame 150 and assembly 101 may be attached to the wall using conventional means such as fasteners (not shown).

[0039] The assembly 101 may, in some embodiments of system 100, be installed in an outdoor environment. Exposure to fluid, precipitation, or condensation from changes in temperature, may cause moisture or water to accumulate in various portions of assembly 101. Drainage of the accumulated moisture, fluid, or water may be achieved through at least one drain hole 158 defined in the lower portion 154 so that gravity facilitates the movement of the accumulated moisture, fluid, or water towards the at least one drain hole 158.

[0040] Referring now to Figs. 5 and 6, an embodiment of elongate member 152 is shown. The elongate member 152 is a straight member that has a length parallel to a first elongate axis 114, wherein the first elongate axis corresponds to the elongate axis of the elongate member 152; and a width parallel to a first short axis 115, wherein the

2019264676 15 Nov 2019 first short axis 115 is perpendicular to the first elongate axis 114. The first elongate axis 114 and the first short axis 115 thereby collectively define a first plane 116. With the exception of the plurality of drain holes 158, the embodiment of elongate member 152 shown in Fig. 5 is identical in configuration to the other elongate members 152 which collectively are comprised in the frame 150; for example, the elongate members 152 comprise identical cross sections. In some embodiments, the cross section may vary when viewed over the first elongate axis 114.

[0041] The elongate member 152 comprises a first end 160 and a second end 162, wherein the second end 162 is disposed opposite first end 160 along the first elongate axis 114. The cross section profile at the extremity of the first end 160 defines a first end face 164, and a second end face 166 is similarly defined at the second end 162. A first portion 178 is parallel to first plane 116, and has a plurality of stiffening formations 168 which spans from the first end 164 to the second end face 166, substantially parallel to the first elongate axis 114. The plurality of stiffening formations 168 at least partially defines a first channel 170, a second channel 172, and a third channel 174. The third channel 174 may alternatively be referred to as a drainage channel, which is also partially defined by a fascia 156 and a bottom connecting surface 176. The fascia 156 is generally perpendicular to the connecting surface 176 and to the first portion 178.

[0042] In some embodiments, the stiffening formations 168 may comprise additional stiffening formations 168 that span in a direction that is not substantially parallel to the first elongate axis 114. For example, the additional stiffening formations 168 may span in a direction that is substantially parallel to the first short axis 115.

[0043] In the embodiment of Figs. 5 and 6, a plurality of drain holes 158 is disposed in the fascia 156 such that the lower edge 159 of the drain holes 158 is substantially aligned with the bottom connecting surface 176 of the drainage channel 174. This alignment of the drain holes 158 facilitates the flow of the accumulated moisture, fluid, or water from the drainage channel 174 and through the drain hole 158. In some embodiments, the first portion 178 and/or the connecting surface 176 of the drainage

2019264676 15 Nov 2019 ίο channel 174 may be slightly inclined with respect to the horizontal (when in use) so that gravity may facilitate the movement of the accumulated moisture, fluid, or water towards at least one drain hole 158. Some embodiments of elongate member 152 may additionally or alternatively define a plurality of drain holes 158 disposed in a different location, for example on the connecting surface 176.

[0044] The second channel 172 may be used to locate a seal 198. In some embodiments, such as shown in Figs. 5 and 6, channel 172 comprises a lip 173 that runs parallel to the elongate axis of channel 172. The lip 173 may be a continuous or intermittent projection along the length of the channel 172, and provides a means for retaining the seal 198 in the channel. The seal 198 may be a rubber or elastomeric material capable of being deformed while being installed the channel 172, and then expanding to fill the space. Placing the seal 198 in the channel 172 provides a seal against the wall or structure 102 when the assembly 101 is installed as part of system 100. In some embodiments where the frame 150 and/or assembly 101 is attached to the wall 102 with fasteners, tightening the fasteners may compress the seal 198 against the wall 102, causing it to expand in an outward or lateral direction to effect a seal that is resistant to water ingress.

[0045] Some embodiments of the frame member 152 may have a length in the range of 300mm to 4500mm, a width in the range of 100mm to 600mm, and a height in the range of 50mm to 200mm. For example, the embodiment of the frame member in Fig. 6 has a width K of 127mm and a height M of 63mm. The fascia 156 may extend from the connecting surface 176 by a distance L, which for example in the embodiment of the frame member in Fig. 6, extends perpendicularly by approximately 39mm to partially overlap with the wall or structure 102.

[0046] The elongate member 152 shown in Figs. 5 and 6 is configured to be coupled to another embodiment of elongate member 152 at the members’ respective first and second opposite end faces 164, 166. In some embodiments, the first and second end faces 164, 166 may be angled with respect to the first elongate axis 114, such that when the frame 150 is assembled, the corners have a mitred or bevelled appearance. For

2019264676 15 Nov 2019 example, to produce the rectangular configuration of Fig. 4, each of the elongate members 152 has first and second end faces 164, 166 that are each angled at 45 degrees from the first elongate axis 114. The first end face 164 of one of elongate member 152 is placed in mating alignment with the second end face 166 of another of elongate member 152 so that the respective grooves 170 are aligned and the respective first portions 178 of the adjoining elongate members are perpendicular to each other.

[0047] In some embodiments, a friction-based connector 184 as shown in Fig. 7 is configured to couple two of the elongate members 152 at their respective first channels 170 and/or at their respective second channels 172. The connector 184 comprises a first elongate portion 186 and a second elongate portion 190. The first elongate portion 186 is elongate about a first elongate axis 194, and the second elongate portion 190 is elongate about a second elongate axis 196. Some embodiments of the connector 184 may be substantially smooth, whereas other embodiments such as in Fig. 7 may feature a form of texturing to grip a surface 171 of channel 170. For example, the first elongate portion 186 comprises texturing in the form of a first serrated portion 188, and the second elongate portion 190 comprises texturing in the form of a second serrated portion 192. To produce the frame 150 in the rectangular configuration of Fig. 4, the connector 184 is “L-shaped” wherein the first elongate axis 194 is perpendicular to the second elongate axis 196. When the first elongate portion 186 of the connector 184 is placed in the channel 170 at the first end of one of the elongate members 152, the first serrated portion 188 may frictionally engage with a surface 171 of the channel 170 to provide a means to locate the other of the elongate members 152 so that channels 170, 172, 174 can be aligned in relation to their counterparts. The second end of the other elongate member 152 can then be disposed such that a surface of its channel 170 frictionally engages with the second serrated portion 192 in the manner shown in Fig.

8. With regard to Fig. 8, a partial perspective view is shown illustrating an example of the installation of connector 184 in the channels 170 of two elongate members 152. In Fig. 8, the hatched region represents the location of the inner surfaces 171 engaged by the serrated portions 188, 192 of the connector 184.

2019264676 15 Nov 2019 [0048] Turning now to the screening elements, as previously described, the assembly 101 comprises at least one screening element 120 disposed in a frame 150, wherein each screening element has acoustic attenuation qualities. The screening element 120 comprises a louvre such as that exemplified by 222, or 322, which is configured to substantially divert fluid or precipitation 107 away from the inner surface 108 of the wall or structure 102 (and internal space 103) by being suitably oriented relative to the direction of the fluid or precipitation, when installed as part of assembly 101.

[0049] In some embodiments, the screening element 120 comprises a louvre 222 with a sound absorbing material 200. The sound absorbing material 200 is configured to absorb some of the energy of the sound waves 105, typically by transferring the kinetic energy of the vibrating air particles in the sound waves 105 into movement of the particles of the sound absorbing material 200, and/or by converting the kinetic energy into heat through interaction with the particles of the sound absorbing material 200.

[0050] Referring now to Figs. 9 and 10, some embodiments of the louvre, 222, are shown. The embodiment of the louvre 222 is configured to be an elongate structure which comprises an inner portion 224, an outer portion 226, a first portion 228, a second portion 230, a first end 232 with a first end face 233, and an opposite second end 234 with a second end face 235. The inner portion 224 comprises first and second inner surfaces 236, 237 that are obtusely angled to each other, and first and second outer surfaces 238, 239. Similarly, the outer portion 226 comprises first, second, and third inner surfaces 240, 241, 242, and first, second, and third outer surfaces 243, 244, 245. The inner portion 224 and outer portion 226 are so named as the louvre 222 is configured such that when assembly 101 is installed as part of an embodiment of system 100, the inner portion 224 corresponds to the inner surface 108 of the wall or structure 102, and the outer portion 226 corresponds to the outer surface 110 of the wall or structure 102. The inner and outer portions 224, 226 are connected or at least arranged to be fixed in relation to each other at the first and second portions 228, 230. The first and second portions 228, 230 may alternatively be respectively referred to as the upper and lower portions of the screening element 120.

2019264676 15 Nov 2019 [0051] The louvre 222 is elongate about a second elongate axis 117 that corresponds to the elongate axis of the louvre 222. In some embodiments, the louvre 222 is a straight member that has a length parallel to the second elongate axis 117, and a width parallel to a second short axis 118, wherein the second short axis 118 is perpendicular to the second elongate axis 117. The second elongate axis 117 and the second short axis 118 thereby collectively define a second plane 119.

[0052] The end faces 233, 235 are substantially perpendicular to the second plane 119. The inner portion 224 comprises a solid portion 246 that is partially defined by the first and second end faces 233, 235, a first inner surface 236, a second inner surface 237, a first outer surface 238, and a second outer surface 239. The outer portion 226 comprises a first inner surface 240, a second inner surface 241, a third inner surface 242, a first outer surface 243, a second outer surface 244, and a third outer surface 245.

[0053] The louvre 222 comprises at least one stiffening formation, parallel to elongate axis 117, which is configured to provide additional rigidity over the length of the louvre. The at least one stiffening formation comprises a screw sleeve 248 with an inner surface 249. The at least one stiffening formation is disposed on the inner surfaces 236, 237, 240, 241, 242.

[0054] In some embodiments, the first portion 228 may comprise a lip 229, and the second portion 230 may comprise a lip 231. For example as shown in Figs. 9 and 10, the inner portion 224 may be a separate piece which is disposed relative to the outer portion 226 where it is retained by lips 229, 231. In other embodiments, the inner portion 224 and outer portion 226 may be formed as a single piece, for example as a single extrusion. When viewed together, the inner and outer portions 224, 226 define a space or cavity 225 therebetween, which in some embodiments is used to contain the sound absorbing material 200. The sound absorbing material 200 (represented by the hatched area in Fig. 10) at least partly fills the cavity 225 and in some embodiments fills substantially the whole cavity 225. The sound absorbing material 200 may fill approximately 80% to 99% of the cavity 225. Fig. 10 is merely illustrative of the quantity of the sound absorbing material 200 and the extent to which it fills the cavity

2019264676 15 Nov 2019

225; the sound absorbing material 200 is shown to fill less than 80% to 99% of the cavity 225 so that other features of the louvre 222 may be more clearly shown and referenced. The sound absorbing material 200 may be coupled to at least one of the inner surfaces 236, 237, 240, 241, 242 of the louvre 222, for example with an adhesive.

[0055] Some embodiments of louvre 222 may comprise a solid portion 246 defining perforations or apertures 247. In some embodiments, the apertures 247 may be a plurality of apertures disposed in an array of apertures. The apertures 247 may comprise a generally circular shape with a diameter between approximately 1mm and approximately 10mm. Other shapes may be used for the apertures 247, comprising for example a slotted, triangular, or squared shape having a similar area range to the circular shaped apertures 247. Some embodiments of the screening element 120 may comprise an inner portion 224 with the solid portion 246 defining apertures 247 equivalent to approximately 10% of the area of any one of the inner surfaces 236, 237. Embodiments of the inner portion 224 defining the apertures 247 may be described as a perforated inner portion 224. Other embodiments may comprise apertures 247 equivalent to approximately 50% of this area. In consideration of the acoustic performance with regard to noise absorption, the apertures 247 are typically limited to approximately 11-30% of this area. For example, approximately 11% coverage of the area of any one of the inner surfaces 236, 237 may be achieved with the apertures 247 having a 2.38mm diameter, each aperture 247 respectively spaced apart in an array at 6.74mm centres. Similarly, approximately 30% coverage may be achieved by the apertures 247 having a 3.25mm diameter, in an array at 5.59mm centres.

[0056] The apertures 247 may provide various advantages. For example, reducing the weight of the screening element 120 may be desirable, such as in embodiments of assembly 101 spanning longer lengths or comprising a plurality of screening elements. Another advantage may be to allow moisture or condensation to escape from the inside of the screening element 120, or where sound absorbing material 200 is present inside, to allow the material 200 to dry if it becomes damp. Yet another advantage may be to allow the visibility of the condition of the inside of the screening element 120, or where sound absorbing material 200 is present inside, to allow visibility of the material 200. A

2019264676 15 Nov 2019 further advantage may be to enable the vibrating air particles of the sound wave 105 to directly contact the sound absorbing material 200 through the apertures 247.

[0057] Examples of suitable sound absorption materials 200 include “Supertel”, “Ultratel”, and “Thermatel”. These are glasswool insulation materials by CSR Bradford, although other approved insulation materials may be used alternatively or in combination. The density of the “Supertel”, “Ultratel”, and “Thermatel” sound absorption material 200 may be between approximately 32kg/m³ and approximately 48kg/m³, for example. In some embodiments, the sound absorbing material 200 includes a flexible piece or sheet of material coupled to at least one of the inner surfaces 236, 237. A minimum thickness of the sound absorbing material 200 is approximately 60mm. In some embodiments, a maximum thickness of the sound absorbing material 200 is approximately 100mm.

[0058] In some embodiments, the louvre 222 connects at its opposite first and second ends 232, 234 to the adjoining frame members 152. In some embodiments, a fastener 180 may engage with the inner surface 249 of the screw sleeve 248, wherein the fastener 180 mechanically couples the frame member 152 to the louvre 222. A plurality of fasteners 180 may engage with a respective plurality of screw sleeves 248.

[0059] In some embodiments, the louvre 222 has a rhomboid cross section, wherein the outer portion 226 comprises a first outer surface 243 which is inclined from the second plane 119, and wherein the outer portion 226 further comprises a second outer surface 244 that is substantially vertical.

[0060] Fluid or precipitation 107 striking the screening element may be diverted to flow away from the internal space 103 given the configuration of at least one of the outer surfaces 243, 244, 245 which may be angled with respect to plane 119. For example, in the embodiment of Figs. 9 and 10, the first outer surface 243 is inclined and the second outer surface 244 is substantially perpendicular with respect to plane 119. In this configuration, fluid 107 striking the first outer surface 243 will typically flow under gravity towards second outer surface 244.

2019264676 15 Nov 2019 [0061] A further consideration is that high air flow may cause fluid 107 striking the louvres 222 to sluice or spill off the louvres and be blown or sucked through the spaces between the louvres. It may therefore be desired for the louvre 222 to comprise a means for reducing or preventing the sluicing or spillage of fluid from the louvres 222.

[0062] The first portion 228 (upper portion of the screening element 120) comprises a deflector 250 disposed adjacent to the outer portion 226. The deflector 250 comprises a lip 252 and a first transition surface 254, wherein the lip is configured to reduce the likelihood of the fluid 107 being diverted from the first outer surface 243 onto the first portion 228. For example, in the embodiment of Figs. 9 and 10, strong air flow may force fluid 107 striking the first outer surface 243 to move inwardly and upwardly towards the first portion 228, instead of typically flowing towards the second outer surface 244 by gravity. The first transition surface 254, which adjoins the lip and the first outer surface 243, may also be configured to feature a curve or a recurve to reduce or hinder such movement of rain further inwardly from the first outer surface, and thus encourage fluid 107 to flow towards the lower portion of the screening element (second portion 230), for example along the second outer surface 244 and subsequently towards a gutter or channel 260.

[0063] The louvre 222 further comprises a third outer surface 245. The third outer surface 245 is angled with respect to the second outer surface 244 and is configured to encourage fluid 107 striking the louvre 222 to flow from the second outer surface 244 to the channel 260. A second transition surface 270 is disposed between the second and third outer surfaces 244, 245, and is configured to smoothen the flow of the fluid 107 between the surfaces 244, 245 as it moves towards the channel 260.

[0064] The channel 260 spans the length of the louvre 222 between first and second ends 232, 234. The channel 260 comprises a first wall 262 and a second wall 264, connected by a bottom surface 266. The first wall 262 connects to the third outer surface 245, and in some embodiments the configuration of the walls 262, 264 and the surfaces 266, 245, 244, 270 may cause a cross-section of the lower portion of the screening element 120 (second portion 230) to resemble an upside-down question mark

2019264676 15 Nov 2019 or a hook shape. In some embodiments, the second surface 244 is parallel and/or coplanar with the second wall 264. In some embodiments, the second wall 264 is substantially vertical or perpendicular to the ground to retain the fluid 107 in the channel up to a specified depth. For example, a suitable depth of the channel 260 may be approximately 20mm to 30mm, and the width of the channel may be approximately the same. Furthermore, in some embodiments, the bottom surface 266 may be inclined such that fluid 107 in the channel 260 is encouraged to flow towards one or both of the first and second ends 232, 234 of the louvre 222. At least one and preferably both of the ends of the channel 260 is open to allow the collected fluid or liquid to drain from the lower portion 154.

[0065] Referring now to Fig. 11, a cross section of system 100 is shown, wherein assembly 101 is installed in a wall or structure 102. In this embodiment of system 100, assembly 101 comprises a plurality of screening elements 120 disposed in frame 150, wherein each of the plurality of screening elements 120 comprises an embodiment of the louvre, for example louvre 222, with the sound absorbing material 200. The assembly 101 separates a noise source 104 emitting sound waves 105 in a room 103, from a human receiver 106 and rain 107 while allowing airflow through the gaps between the individual screening elements 120. The assembly 101 may also reduce intrusion of noise into the room 103 as well as reducing noise escaping from the room 103. In some embodiments, the assembly 101 has a minimum sound reduction index Rw rating of 6. An Rw6-rated assembly would reduce the level of sound passing through the assembly by approximately 6 decibels, which by way of example may give the human receiver 106 the impression that the sound has reduced by approximately one quarter. In some embodiments, the assembly 101 has a Rw rating between Rw6 and Rw30. The Rw rating may be controlled by the amount of the sound absorbing material 200, the size of the screening element 120, and/or the spacing between the screening elements 120 (marked “V” on Fig. 11).

[0066] When viewed in cross-section, embodiments of the louvre 222 may have dimensions in the range of 100mm to 200mm for the width, and 200mm to 300mm for the height. For example, the embodiment of the louvre 222 shown in Fig. 10 may have

2019264676 15 Nov 2019 a width P of 122mm and a height Q of 239mm. In some embodiments, the louvre 222 has a width P of approximately 100mm, and comprises an approximately 63mm thick piece of the sound absorbing material 200, providing a Rw6 rating. In some embodiments, the louvre 222 has a width P of approximately 200mm, and comprises an approximately 63mm thick piece of the sound absorbing material 200, providing a Rwl 1 rating. Embodiments of the louvre 222 with a width P of 400mm may comprise an approximately 100mm thick piece of the sound absorbing material 200. The louvres may come in various lengths depending on the application. For example, for a louvre that is supported only at its first and second ends, a typical length would be in the range of 300mm to 2000mm. Longer lengths of louvres may require support at intermediate locations along the length of the louvre in addition to the end supports. When installed together with frame 150 to form assembly 101, assembly 101 may have a height in the range of 340mm to 6000mm, and a length in the range of 300mm to 6000mm. For example, the embodiment of assembly 101 shown in Fig. 11 may have a width S of 150mm, a height T of 1200mm, and a screening element spacing V of 150mm. The screening element spacing V is the distance between corresponding points of adjacent screening elements 120. For example, Fig. 11 shows spacing V measured between the adjacent channels 260.

[0067] In some embodiments, the combination of the spacing V and the inclination of the first outer surface 243 with respect to plane 119 (Fig. 9) results in the first (upper) portion 228 of at least one of the screening elements 120 being in an overlapping arrangement with the second (lower) portion 230 of an adjacent screening element 120. In some embodiments, for example as shown in Fig. 11, the first and second portions 228, 230 of adjacent screening elements 120 are in an overlapping arrangement with each other. The overlapping arrangement means that for embodiments of the assembly 101 installed vertically as shown in Fig. 11, the assembly 101 substantially obscures the internal space 103 from view when the assembly 101 is viewed head-on (perpendicular to the wall 102) or viewed from the angle indicated by the arrow representing fluid 107.

[0068] The relative placement of the screening elements 120 in the frame 150 has an effect on the air flow and sound travel through the assembly 101. A larger spacing V of

2019264676 15 Nov 2019 the screening elements permits greater air flow, but allows more sound to pass through the assembly. Conversely, a smaller spacing V is more effective at impeding the passage of the sound waves 105 from the internal space 103 and/or the ingress of the fluid 107 to the internal space 103, but a smaller spacing V reduces the ventilation capacity of the assembly 101. The screening elements 120 may be spaced so that spacing V is in the range of 100mm-250mm centres. For example, typical spacing V may be set at 150mm centres of the screening elements, or at 165mm centres.

[0069] Fig. 12 is a detail view showing the flow of the fluid 107. Fluid 107, such as rain, strikes the outer portion 226 of screening element 120. As indicated by the dashed lines, some of the fluid 107 may sluice or spill directly off the outer portion 226 and fall outside of the channel 260, while preferably most of the fluid 107 trickles along the outer portion 226 and accumulates in channel 260. In some embodiments, particularly where the channel 260 is parallel or coplanar with the second outer surface 244, the third outer surface 245 is recessed inwards from the second outer surface 244, and the second transition surface 270 is configured to create a gradual change in angle between the second and third outer surfaces 244, 245 so that preferably most of the fluid 107 remains attached to the second and third outer surfaces 244, 245 and flows into the channel 260. The screening element 120 is coupled via screw sleeves 248 at first and second ends 232, 234 to the frame member 152 such that the channel 260 is configured to interface with the third channels 174 of the frame members 152. Consequently, the fluid 107 flows from the channel 260, through the third channels 174, and out of the drain holes 158 as indicated by the dashed line. The cladding piece 157 may prevent overflow of the fluid 107 from the channel 260.

[0070] While the disclosed embodiments of the louvre 222 have the aforementioned inner and outer surfaces, it should be appreciated that other embodiments may comprise fewer or more inner and outer surfaces depending on the cross-sectional shape. The embodiment of louvre 222 shown in Figs. 9 to 12 has a generally rhomboid shape in cross-section, however another embodiment of the screening assembly 120 may have a cross-section that is generally elliptical, triangular, chevron, or aerofoil shaped, for

2019264676 15 Nov 2019 example. In Fig. 13, another embodiment of the louvre, 322, has a chevron configuration in cross-section.

[0071] The louvre 322 is configured to be largely similar to louvre 222, and thus louvre 322 is also an elongate structure which comprises an inner portion 324, an outer portion 326, a first portion 328, a second portion 330, a first end 332 with a first end face 333, and a second end 334 with a second end face 335. The inner portion 324 comprises first and second inner surfaces 336, 337, 337A and first and second outer surfaces 338, 339, 339A. Similarly, the outer portion 326 comprises first, second, and third inner surfaces 340, 341, 342, and first, second, and third outer surfaces 343, 344, 345. As with the louvre 222, the louvre 322 comprises a solid portion 346 which in some embodiments of louvre 322 may define apertures 347 of a similar configuration to the apertures 247. In some embodiments, the portions of the louvre 322 comprising the surfaces 337A and 342 may additionally define apertures 347 disposed in the surfaces 337A and 342 as shown in Fig. 13.

[0072] The nomenclature of the louvre 322 is intended to reflect the counterparts of the louvre 222; for example, the first end 332 is intended to generally functionally correspond to the first end 232. Corresponding with louvre 222, the louvre 322 is similarly elongate about a second elongate axis 117 that corresponds to the elongate axis of the louvre 322.

[0073] Some embodiments of the louvre 322 may comprise a deflector 350 that is equivalent to the deflector 250, and a channel 360 that is equivalent to the channel 260. The louvre 322 differs from the louvre 222 in that the inner portion 324 comprises a channel 360, in addition to the channel 360 disposed on the outer portion 326 as per channel 260 disposed on the outer portion 226. The channel 360 disposed on the inner portion 324 may accumulate any fluid (not necessarily fluid 107) that may contact the inner portion, and functions the same way as channel 260 to drain the fluid through drain holes 158. Embodiments of frame 150 configured to be coupled with louvre 322 may therefore comprise a plurality of third (drainage) channels 174, which respectively positionally correspond with the plurality of channels 360. The configuration of the

2019264676 15 Nov 2019 louvre 322 may be approximated by an adjacent combination of two of the louvre 222 disposed in an adjacent combination of two of the frame 150. Similar to the louvre 222 which attaches to frame members 152 by way of screw sleeves 248, the louvre 322 attaches to frame members 152 by way of screw sleeves 348. Embodiments of louvre 322 may be formed as a single piece, or from a plurality of separate pieces assembled together. For example, the portions of the louvre 322 comprising the surfaces 337A and 342 may be separable from the rest of the louvre 322. These separable portions may be retained in a lip 331 which is similar in position and configuration to the lip 231.

[0074] When viewed in cross-section, embodiments of the louvre 322 may have dimensions in the range of 250mm to 550mm or 600mm for the width, and 200mm to 400mm for the height. For example, the embodiment of the louvre 322 shown in Fig. 13 may have a width X of 400mm and a height Y of 230mm. In some embodiments, the louvre 322 has a width X of 400mm and comprise an approximately 100mm thick piece of the sound absorbing material 200. Similar to louvre 222, embodiments of the louvre 322 may come in various lengths depending on the application. For example, for a louvre that is supported only at its first and second ends, a typical length would be in the range of 300mm to 6000mm. Longer lengths of louvres may require support at intermediate locations along the length of the louvre in addition to the end supports.

[0075] In some embodiments, the screening element 120 comprises a louvre with sound absorbing material 200, wherein the screening element 120 may be one of the embodiments of the louvre 222, 322 as disclosed herein. Similar to the louvre 222, the louvre 322 may comprise a cavity 325 similar to the cavity 225, wherein the sound absorbing material 200 (represented by the hatched area in Fig. 13) at least partly fills the cavity 325 and in some embodiments fills substantially the whole cavity 325. The sound absorbing material 200 may fill approximately 80% to 99% of the cavity 325. Fig. 13 is merely illustrative of the quantity of the sound absorbing material 200 and the extent to which it fills the cavity 325; the sound absorbing material 200 is shown to fill less than 80% to 99% of the cavity 325 so that other features of the louvre 322 may be more clearly shown and referenced. In some embodiments, the louvre 322 has a

2019264676 15 Nov 2019 width X of approximately 600mm, and comprises an approximately 100mm thick piece of the sound absorbing material 200, providing a Rw30 rating.

[0076] In some embodiments, the frame members 152 and the louvres 222, 322 are fabricated wholly or in part from aluminium extrusions. Aluminium extrusions suitable for use as louvres and frame members may be commercially available through suppliers such as Capral, however alternative embodiments of structures (i.e. louvres) shown in Figs. 1 to 13 can be manufactured using custom dies. Some embodiments of the frame members 152 and the louvre 222, 322 are fabricated from AL 6063 grade aluminium, with a 2.5mm wall thickness of the extrusion. Other grades of aluminium and dimensions may be used if structurally adequate. For example, other suitable wall thicknesses of the extrusion may be in the range of 1mm to 6mm.

[0077] The aluminium extrusions may be treated and finished with various surface coatings, for example anodising or powder coating to provide corrosion protection and/or cosmetic benefits. For example, conversion coating through a chromating process may be performed prior to powder coating. An environmentally friendlier alternative is a non-chrome based conversion coating, which may alternatively be used as pre-treatment for powder coating. An example of a suitable non-chrome based coating is the “E-CLPS” product manufactured by Bulk Chemicals Incorporated and supplied in Australia by Elite Surface Technologies.

[0078] Some embodiments of the frame and/or louvres may be manufactured wholly or in part from materials other than aluminium. For example, some embodiments may comprise stainless steel, mild steel, galvanised steel such as galvabond, polyolefin, or a composite material such as fibreglass.

[0079] An acoustic louvre assembly 101 for acoustic attenuation has therefore been disclosed. Embodiments and variations of assembly 101 may provide a solution for noise reduction while accommodating the passage of air with minimal restriction. Embodiments and variations of assembly 101 when installed as part of system 100 may provide a noise and weather barrier while providing an opening for ventilation.

2019264676 15 Nov 2019

Embodiments and variations of assembly 101 may be suitable for use in commercial and industrial environments, such as in the mining, food processing and specialist manufacturing industries. For example, commercial and industrial installations may include plant room ventilation, provision of relief air to manufacturing spaces, air conditioning installations, cooling towers, power generation equipment, refrigeration plant, and acoustic enclosure ventilation.

[0080] The acoustic transmission attenuation will be tested in accordance with AS1191-2002 and ISO 10140-2:2010. Water penetration tests will be in accordance with AS4740-2002 & BS EN 13030-2001 & ANSI/AMCA 500L. Some embodiments of the acoustic louvre assembly 101 may be configured to achieve a sound transmission loss, in accordance with AS1191-2002, in excess of 35dB at the frequency of 1000Hz.

[0081] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

[0082] Throughout this specification the word comprise, or variations such as comprises or comprising, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

[0083] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification 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 disclosure as it existed before the priority date of each of the appended claims.

Claims (15)

1. CLAIMS:

   1. A screening element for a louvre assembly, the screening element comprising: an outer portion having an outer surface which, in use of the screening element, can be exposed to environmental fluids and is sloped to direct liquid on the outer surface toward a lower portion of the screening element;

   an inner portion having a solid portion defining a plurality of apertures, the inner and outer portions arranged to define a cavity therebetween;

   a sound absorbing material disposed in the cavity, the sound absorbing material configured to create a sound differential between the inner and outer portions;

   wherein the lower portion of the screening element defines a drainage channel to collect the liquid, the drainage channel being open at at least one end to allow collected liquid to drain from the lower portion.
2. 2. The screening element of claim 1, wherein the lower portion defines a front face and the drainage channel is recessed relative to the front face.
3. 3. The screening element of claim 2, wherein the lower portion defines an inwardly angled surface disposed, in use, below the front face and configured to cooperate with the front face to induce liquid flowing along the front face to flow toward the drainage channel.
4. 4. The screening element of any one of claims 1 to 3, wherein the drainage channel is open at first and second opposed ends.
5. 5. The screening element of claim 2 or claim 3, wherein a cross-section of the lower portion resembles an upside-down question mark or hook shape.
6. 6. The screening element of claim 2, 3 or 5, wherein the drainage channel is defined by channel walls in the lower portion, and wherein the channel walls comprise an outer lip that is substantially flush with the front face.

   2019264676 15 Nov 2019
7. 7. The screening element of any one of claims 1 to 6, wherein the screening element comprises a deflector on an upper portion of the screening element, the upper portion disposed opposite the lower portion, and the deflector configured to direct the liquid towards the lower portion of the screening element.
8. 8. A louvre assembly, comprising:

   a frame having at least one drain hole; and at least one screening element mounted with the frame; said screening element comprising a drainage channel, a perforated inner portion, and a sound absorbing material, the sound absorbing material configured to absorb sound waves contacting the screening element, and the frame including a drainage arrangement for directing liquid accumulated within the drainage channel to the at least one drain hole.
9. 9. The assembly of claim 9, wherein at least some of the sound waves pass through the perforated inner portion to be at least partly absorbed by the sound absorbing material.
10. 10. The assembly of claim 8 or claim 9, wherein the screening element is configured to divert the liquid contacting the screening element such that the liquid accumulates in the drainage channel.
11. 11. The assembly of any one of claims 8 to 10, wherein the drainage channel is configured to cooperate with the at least one drain hole of the frame such that the liquid in the drainage channel accesses the at least one drain hole through the frame.
12. 12. The assembly of any one of claims 8 to 11, wherein the assembly comprises a plurality of the screening elements, each one of the screening elements comprising an upper portion disposed opposite a lower portion, and the plurality is arranged in the frame so that the lower portion of one of the plurality of screening elements overlaps with the upper portion of an adjacent one of the plurality of screening elements.

    2019264676 15 Nov 2019
13. 13. The assembly of claim 12, wherein the lower portion of each one of the plurality of screening elements overlaps with the upper portion of an adjacent one of the plurality of screening elements.
14. 14. A louvre assembly, comprising:

    a frame having at least one drain hole; and at least one screening element in accordance with any one of claims 1 to 7, the at least one screening element mounted with the frame so that the liquid collected in the drainage channel is directed to the at least one drain hole.
15. 15. A system for acoustic attenuation, comprising the assembly of any one of claims 8 to 13 or the assembly of claim 14, configured to be disposed in a wall or structure to provide acoustic attenuation of a noise source shielded therewith.