AU2013202385B2 - Sub-floor ventilator - Google Patents

Abstract

A sub-floor ventilator and a sub-floor ventilation system is disclosed. The ventilator comprises a mount, for mounting to a sub-floor structure. The ventilator also comprises a housing for attachment to the mount. The housing remains substantially unobscured 5 by the mount, when attached thereto. A fan for directing air flow is located within the housing. The housing is adapted for reversible attachment to the mount, such that the direction of airflow can be reversed. 4218227_1 (GHMaters) P89849.AU.1 eN 0;J _ dL o r4<s (9 r

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): CSR Building Products Limited Invention Title: SUB-FLOOR VENTILATOR The following statement is a full description of this invention, including the best method for performing it know to me/us: - 2 SUB-FLOOR VENTILATOR TECHNICAL FIELD A sub-floor ventilator is disclosed. The ventilator may take the form of an axial 5 flow fan ventilator, and may facilitate the reduction of moisture, and mould and fungus growth in the sub-floor space of a structure. BACKGROUNDART Ventilators can be employed to evacuate air and other gases from enclosed 10 spaces. Such enclosed spaces can include the sub-floor space of commercial and domestic buildings. The condition of air space beneath a building can influence mould and fungal growth, termite activity and the rotting and distortion of timber in a building. When air and other gases are trapped in the sub-floor region, the air can evaporate through the flooring into the common space of commercial and domestic buildings, 15 permeating stale and musty odours, along with mould spores and moisture. One example of a sub-floor ventilator is disclosed in US 6468054. This ventilator comprises two fans, each having a fan housing. The fan housings are inserted into a plastic frame and enclosed by screen mesh located at the inlet and outlet openings of the plastic frame. Similarly, US 2006/0240764 and US 2008/0242212 are directed to 20 supply air boosters. The fan housings, containing ventilation fans, in these devices are inserted into, and supported by, enclosures. The air and other gases evacuated by such systems can include warm or heated gases, moist gases, gas containing contaminants such as contaminated air or toxic fumes, odours and stale gases (especially air) etc. Whilst in some instances it may be 25 preferable to have sub-floor ventilation extract air from within the sub-floor structure, in other instances it may be preferable to draw fresh air into the sub-floor structure. A particular issue with current sub-floor ventilation is the noise created by extraction fans. The above references to the background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in 30 the art. The above references are also not intended to limit the application of the sub floor ventilator and sub-floor ventilation system disclosed herein. 4218227_1 (GHMaters) P89849.AU.1 - 3 SUMMARY OF THE DISCLOSURE According to a first aspect, a sub-floor ventilator is disclosed. The ventilator comprises a mount, for mounting to a sub-floor structure. The ventilator also comprises a housing for attachment to the mount. The housing remains substantially unobscured 5 by the mount, when attached thereto. A fan for directing air flow is located within the housing. The housing is adapted for reversible attachment to the mount, such that the direction of airflow can be reversed. In one embodiment, the housing is attached to the mount in a 'forward' direction to achieve an 'exhaust flow'. The fan rotates in one direction, and the air is exhausted 10 from inside the sub-floor structure to outside the sub-floor structure. When the housing is attached to the mount in the 'reverse' direction, a 'supply (inlet) flow' is achieved. Whilst the fan still only rotates in one direction, because the fan has been inverted, air is drawn from outside the sub-floor structure to inside the sub-floor structure. This can provide efficient air flow performance for both exhaust and supply flow configurations, 15 which is not achievable when using a switch to electrically reverse the direction of fan rotation. This can also allow an installer or user of the sub-floor ventilator to configure the direction of air flow, dependent on the requirements for a specific use (i.e. the installer or user is not limited to purchasing an exhaust or supply configured sub-floor ventilator, as the configuration can be altered after manufacture). It can also allow the 20 user to alter the direction of air flow if, for example, conditions change in the sub-floor space, after the sub-floor ventilator has been installed. In contrast to US 6468054, US 2006/0240764 and US 2008/0242212, the fan housing of the present disclosure is unobscured by the mount. The housing of the present disclosure is not inserted into the mount and, in this regard, the mount does not 25 enclose, or surround, a substantial portion of the fan housing. Such an arrangement reduces the number of parts required and simplifies maintenance and installation of the ventilator. For example, the procedure for reversing the fan does not require the fan to be removed from an enclosure, which could be time consuming and problematic if e.g. dirt causes the fan housing to be wedged in the enclosure. Further, configuring the 30 ventilator such that the housing is unobscured by the mount may allow for enhanced dissipation of heat produced by the fan motor during operation of the ventilator. Additionally, the proportion of sub-floor structure required to be removed for 4218227_1 (GHMaters) P89849.AU.1 - 4 installation of the sub-floor ventilator is also reduced. In one embodiment, a series of peripheral securing regions may be provided around opposing respective ends of the housing to enable the housing to be reversibly secured to the mount. The securing regions may include screw bosses. 5 In one embodiment, the sub-floor ventilator may further comprise an air permeable cover attached to the mount. The cover may provide protection to the fan from the external elements, such as rain and sun, to prevent damage to, and extend the life of, the fan, or may be to obscure access to the fan for safety (e.g. to prevent fingers from entering the fan or motor), or to obscure the view of the fan for aesthetic reasons. 10 The cover may comprise a plurality of louvres. Each louvre may be configured to have a curved transverse profile. A curved louvre profile reduces the air resistance that the air flow encounters as it moves through the ventilator. This gentle guiding of the oncoming air flow by a curved louvre, as opposed to an abrupt straight-angled louvre, reduces flow losses through the reduction of turbulence and flow separation. 15 This also reduces the noise of the ventilator, and can reduce the power required for operation for a given flow rate. In-use, the curvature of each louvre may be concave facing downwardly. This assists with preventing the ingress of rain into the ventilator, thereby increasing the lifespan of the rotating parts. 20 In one embodiment, the cover may be attached to the mount such that it projects externally of the sub-floor structure. In another configuration, the cover may be located within or flush with the e.g. wall or wall cavity of the sub-floor structure. In one embodiment, the cover may be integrally formed with the mount. This can reduce the number of separate components required for sub-floor ventilation and 25 can provide additional structural integrity to both the mount and the cover. In one embodiment, the cover may be mounted to the outside of the sub-floor structure, whilst the mount may extend into the wall, wall cavity and/or the structure itself In one embodiment, the sub-floor ventilator may comprise a second air permeable cover. In this regard, the second cover may include a component similar to 30 the mount and may thus be of the same form as the first cover. This enables a single type of cover to be manufactured, thus reducing production costs. The second cover may be configured to be attached to the housing on an opposite side of the housing to 4218227_1 (GHMaters) P89849.AU.1 - 5 which the mount is attached. The second cover may be attached via, for example, a telescoping sleeve that can slip over, or part of, the housing. The telescoping sleeve can allow for installation in walls of different depths/thickness. The telescoping sleeve may be integrally formed with the second cover, or it may be available as a separate 5 component and act as an intermediary attachment component for attachment of the second cover to the housing. Having covers located on either side of the housing can provide a flow-through arrangement for e.g. a wall. The cover and/or second cover may be in the form of a grille. The grille can provide additional protection from sun damage, water ingress, and can act as a guard to 10 prevent finger entry into the fan area. The housing may be of a substantially cylindrical shape, to encase rotating blades of the fan. The mount may be similarly shaped (i.e. be substantially cylindrical) to correspond to the housing shape. In one embodiment, the mount may comprise at least one pair of diametrically 15 opposed flat edges for providing a close facing relationship with the sub-floor structure when mounted thereto. The mount may otherwise be substantially cylindrical in shape, to correspond to the fan housing. Sub-floor ventilators are generally inserted into a wall of a structure that has a regular repeating pattern, such as timber, brickwork, etc, that has had part of the repeating pattern (e.g. slats of timber, bricks, etc) removed. It can 20 therefore be difficult to insert the cylindrical mount into the structure. The diametrically opposed flat edges of the mount provide a means for simple alignment with the remaining structure. They also allow for insertion of the sub-floor ventilator without the need to remove additional or an unnecessary portion of the structure. The mount may preferably comprise two pairs of diametrically opposed flat 25 edges. This allows the sub-floor ventilator to fit into, for example, a square or rectangular cavity that has been created from the removal of part of the structure. They can minimise the proportion of the sub-floor structure that needs to be removed for insertion of the sub-floor ventilator. In a brick structure, for example, three vertically adjacent bricks may need to be removed so that the sub-floor ventilator can be 30 substituted therefore. The mounting of the mount to the sub-floor structure is facilitated by the close facing relationship of the mount, as provided by the two pairs of 4218227_1 (GHMaters) P89849.AU.1 - 6 diametrically opposed flat edges, with the remaining, for example, brick work (i.e. the flat edges of the mount align with the remaining bricks). Due to additional components that may be required to provide the reversible attachment of the fan housing to the mount (e.g. fasteners on both sides of the housing), 5 the mount and/or fan housing may be slightly larger than other sub-floor ventilators. The pair of diametrically opposed flat edges on the mount also assist with reducing the sizing of the mount, to enable substitution of the sub-floor ventilator into the cavities provided for existing sub-floor ventilators. This eliminates the need to enlarge the cavity for the insertion of the sub-floor ventilator. 10 In one embodiment, the housing may comprise at least one pair of diametrically opposed flat edges for providing a close facing relationship with the sub-floor structure when attached to the mount, and when the mount is mounted thereto. Providing the housing with similarly shaped diametrically opposed flat edges allows simple alignment with the mount when attaching it thereto, and also assists with its substitution into the 15 sub-floor structure. The housing may preferably comprise two pairs of diametrically opposed flat edges, to correspond to the two pairs of diametrically opposed flat edges on the mount. In this respect, the flat edges provide a close facing relationship with the mount, when attached thereto, and the sub-floor structure when the mount is mounted thereto. 20 In one embodiment the housing may further comprise a lip extending peripherally around an end of the housing. The lip may have a diameter corresponding to the portion of the mount to which the housing is attached. This may allow the housing to be aligned with the mount during attachment of the mount to the housing. Both opposing ends of the housing may comprise such a lip. The lip may be curved 25 such that the end of the housing at which the lip is located has a bell-mouth shape. Such a configuration may provide efficient airflow into and out of the fan housing. In one embodiment, the fan may comprise a plurality of blades extending radially from an axis of the fan. At least one flange, which may be in the form of a winglet, may be provided along an outer (distal) edge of at least one blade. The flange, 30 or winglet, can assist in reducing air turbulence at the outer edge (i.e. tip) of each fan blade, which can result in a reduction of the amount of noise generated by the sub-floor ventilator and an improvement its efficiency. One manner in which noise is generated 4218227_1 (GHMaters) P89849.AU.1 in a fan (e.g. an axial flow fan) is by a portion of the air in the fan flowing from the high pressure side of the fan to the low pressure side in the gap between the blade tip and the housing. The flange, or winglet, can create a disturbance which can prevent air flowing into this gap. Preferably a flange, or winglet, can be provided extending from and along 5 both sides of the outer blade edge to maximise the reduction in turbulence. The flange, or winglet, may have an aerofoil profile. In one embodiment, the fan may be motor driven. The motor may be powered by either a direct or alternating current power supply. The motor may additionally comprise a cable to connect the motor to the power supply. 10 In one embodiment, the cable may comprise a control unit for controlling the motor. The control unit may further comprise a sensor for automatic adjustment of the control unit. The sensor may also automatically turn the motor on or off The sensor may sense the temperature, humidity, mould spore count, fungal spore count, carbon dioxide levels, or odours indicative of poor ventilation in a sub-floor structure. The 15 sensor may be multi-functional, or a number of respective sensors may be provided. In one embodiment, the control unit may control the speed of the motor. The speed of the motor controls the speed at which the fan is rotated, and thus how much exhaust, or supply, of air is provided. The speed of the fan can therefore be altered depending on the prevailing conditions in the sub-floor space. 20 In one embodiment, the cable may comprise three distinct portions. A first cable portion may be attached to the motor at one end thereof and the second end thereof may be adapted for connection to the second cable portion. A second cable portion may comprise a first connection end for connection to the second end of the first cable portion and a second connection end. A third cable portion may comprise an 25 end for connection to the power source and the second end thereof may be adapted for connection to the second connection end of the second cable portion. The control unit may be located in proximity to the first connection end of the second cable portion. For example, the length of cable between the first connection end and the control unit may be only, for example, 5 - 50cm. The length of cable between the second connection 30 end and the control unit may be, for example, 1 - 50m. In this embodiment, the control unit may therefore be located near the motor of the ventilator. This allows the location of the control unit to be changed by simply reversing 4218227_1 (GHMaters) P89849.AU.1 - 8 the way the second cable portion connects to the first and third cable portions. When the first connection end of the second cable portion is connected to the second end of the first cable portion, and the second connection end of the second cable portion is connected to the second end of the third cable portion, the control unit is located near 5 the motor and fan of the sub-floor ventilator. When these connections are reversed (i.e. when the first connection end of the second cable portion is connected to the second end of the third cable portion, and the second connection end of the second cable portion is connected to the second end of the first cable portion), the control unit will be located near the power supply (i.e. power point). This allows a user to decide the best 10 or most convenient location for the controller. For example, in some sub-floor structures it may be easier to access the power supply, so it is more convenient to have the control unit located in proximity to the power supply. In other sub-floor structures it may be easier to access the sub-floor ventilator, so it would be more convenient to have the control unit located in proximity to the sub-floor ventilator. The alterable 15 cabling provides flexibility for the installer and/or end user of the sub-floor ventilator, whilst providing a "universal" control cable, thus eliminating the need to produce different cables and/or sub-floor ventilators for different uses. Also second cable portions with differing control unit locations therealong can be interchanged in between the first and third cable portions. 20 In one embodiment, the first and second connection ends of the second cable portion may be of the same connection type. Similarly, the second ends of the first and third cable portions may be adapted for connection with the same connection type (i.e. the same connection type used in the second cable portion). The connection ends of the second cable portion may be plugs for connection with sockets (i.e. the second ends) of 25 the first and third cable portions. Alternatively, the connection ends of the second cable portion may be sockets, and the second ends of the first and third cable portions may be plugs. In one embodiment, connection of the second cable portion to the first and third cable portions may be reversed. As mentioned above, this can allow the location of the 30 control unit to be altered with respect to the power supply, thus enabling the user to decide where the most convenient location for the control unit is (i.e. close to the fan or close to the power supply). 4218227_1 (GHMaters) P89849.AU.1 - 9 In one embodiment, the motor may be located within the housing. This can provide additional protection of the motor and assists with preventing degradation of the motor due to sun, water, etc. Additionally or alternatively, this may obscure access to the motor for safety reasons. 5 In one embodiment, the fan may be attached to the housing via one or more support arms. The support arms can provide structural rigidity to the housing and additional support to the fan. One or more of the support arms may comprise a channel for locating and storing a cable therein. The channel or conduit can provide a dedicated space for a 10 cable, for example the motor cable, to be located, thus ensuring that it does not interfere with or become entangled in the fan, including during reverse of the housing. In this regard, in one embodiment, an outer periphery of the housing may comprise at least one channel for locating and storing a cable therein. The housing channel can also provide a dedicated space for a cable, to ensure that it does not 15 interfere with or become entangled in the fan. This may be particularly important, due to the reversibility of the fan and housing with respect to the mount. In one embodiment, the motor may be located on the mount side of the housing, while the fan is located on the sub-floor space side (i.e. in an exhaust flow configuration). However, if the housing is reversed, the fan may be located on the mount side of the housing, 20 while the motor is located on the sub-floor space side (i.e. in a supply flow configuration). When the motor is on the mount side of the housing, the cable can be difficult to pass through to the internal structure (to supply power to the motor). Thus, a channel at an outer periphery of the housing can provide a simple course for the cable to be passed back to the sub-floor space, whilst ensuring that the cable does not interfere 25 with or become entangled in the fan. The channel may simply be aligned grooves on either side of the outer periphery of the housing. The grooves may be aligned with the channel in the support arm, to enable the cable to pass to the power supply without impeding the fan when the housing is mounted to the mount in either the exhaust or supply configurations. 30 In one embodiment, the housing may attach to the mount via screws. The housing and or mount may comprise a boss for the screw to assist with attachment. Other forms of attachment may also be appropriate, such as a sliding latch, press fit, etc. 4218227_1 (GHMaters) P89849.AU.1 - 10 According to a second aspect, a sub-floor ventilation system is disclosed. The ventilation system is for ventilating air from within, or into, a structure and comprises a motor-driven ventilator, as defined in the first aspect, for mounting to the structure. 5 The system further comprises a controller for controlling the speed of the ventilator motor, and a sensor for sensing at least one condition within the structure. The controller is adapted for controlling the speed of the ventilator motor in response to the or each condition sensed within the structure. In one embodiment the ventilator is mounted to a sub-floor wall. 10 In another embodiment, the at least one condition can include, temperature, humidity, mould spore count, fungal spore count, carbon dioxide levels or odours. The sensor may be multi-functional, or a number of respective sensors may be provided. In one embodiment, the controller may control the speed of the motor. The speed of the motor controls the speed at which the fan is rotated, and thus how much 15 exhaust, or supply, of air is provided. The speed of the fan can therefore be altered depending on the prevailing conditions in the sub-floor space. In one embodiment the motor may comprise a cable to connect the motor to the power supply. The controller may be integrated with the cable. In one embodiment the cable may comprise first, second and third distinct 20 portions. The first cable portion may be attached to the motor at one end thereof and the second end thereof adapted for connection to the second cable portion. The second cable portion may comprise a first connection end for connection to the second end of the first cable portion and a second connection end. The third cable portion may comprise an end for connection to the power source and the second end thereof adapted 25 for connection to the second connection end of the second cable portion. The controller may be located in proximity to the second connection end of the second cable portion. The first and second connection ends of the second cable portion may be of the same connection type. The second ends of the first and third cable portions may adapted for connection with the same connection type. 30 The connection of the second cable portion to the first and third cable portions may be reversible. In this regard, the location of the controller, with respect to the ventilator and power source, may be altered by reversing the second cable portion. 4218227_1 (GHMaters) P89849.AU.1 - 11 BRIEF DESCRIPTION OF THE DRAWINGS Notwithstanding any other forms which may fall within the scope of the sub floor ventilator and ventilation system as set forth in the Summary, specific 5 embodiments will now be described, by way of example only, with reference to the accompanying drawings in which: Figures 1A and 1B, respectively, show rear perspective views of a sub-floor ventilator in exhaust and inflow modes; Figures 2A and 2B, respectively, show side sectional views of the ventilators io shown in Figures 1A and 1B; Figure 2C shows a detail view of line A of Figure IA; Figure 3A shows a front view of the sub-floor ventilator shown in Figures 1B and 2B; Figure 3B shows a sectional view along line A-A of Figure 3B; 15 Figure 3C shows a detail view of line B of Figure 3B; and Figure 4 shows a top view of a sub-floor ventilation system. DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS Referring firstly to Figures 1 and 2, an embodiment of a sub-floor ventilator 10 20 is shown. The ventilator 10 is specifically, though not exclusively, configured for reducing moisture and condensation, and for removing odours, from the sub-floor space in buildings. As shown in Figures 1 and 2, the ventilator 10 may be configured in two modes, an exhaust flow (Figures 1A and 2A) and a supply flow (Figure 1B and 2B). An exhaust flow configuration allows air that is trapped in the sub-floor structure to be 25 extracted from within the structure and exhausted to outside the structure. A supply flow configuration allows air from outside the structure to be supplied to the inside of the sub-floor structure. While this can be achieved by electrically reversing the direction of fan rotation, such an arrangement is not preferable due to aerodynamically inefficient air flow in the second (or reversed) direction. 30 The ventilator 10 comprises a fan housing 12 and a mount 14. The mount 14 comprises an air-permeable cover, in the form of a grille 16, and a projection, in the form of a ledge 18 for attachment to the fan housing 12. A motor-driven fan 20 for 4218227_1 (GHMaters) P89849.AU.1 - 12 directing air flow is located within the fan housing 12. The fan 20 comprises a motor unit 22 and a fan 24 axially connected to the motor unit. The fan 24 comprises one or more air-motive elements in the form of fan blades 26. When the ventilator 10 is in an exhaust flow configuration (Figures 1A and 2A), the fan 24 rotates in-use and the fan 5 blades 26 cause air within the sub-floor space to exhausted to outside of the sub-floor structure. When the ventilator 10 is in a supply flow configuration (Figures 1B and 2B), the fan 24 rotates in-use and the fan blades 26 cause air from outside of the structure to flow into the structure. The motor unit 22 comprises a motor rotor 28, which is connected to the fan 24, 10 and a motor stator 30, which is connected to the fan housing 12 via support arms 32. It should be noted that while the motor stator 30 is shown having seven support arms 32, fewer or additional support arms may be used. The support arms 32 are shown extending radially from the motor stator 30. There is sufficient spacing between adjacent support arms 32 to allow adequate air flow through the ventilator 10. 15 The fan housing 12 has rims 36, 38 on either side for connection to ledge 18. The rims 36, 38 may be attached to the ledge 18 via screws 40 and securing regions, in the form of screw bosses 42. The screw bosses 42 are located on either side of the housing 12 at rims 36, 38. Screws 40 are screwed into the screw bosses 42 and, and into ledge 18 to attach the housing 12 thereto. As the rims 36, 38 are of substantially 20 the same form, and as each has screw bosses 42, the fan housing 12 can be attached to the ledge at either rim 36, 38, thereby allowing attachment in either an exhaust or supply flow configuration. When rim 36 is attached to ledge 18, an exhaust flow configuration is achieved. When rim 38 is attached to ledge 18, a supply flow configuration is achieved. As the fan 24 only rotates in one direction (because the fan 25 24 can be attached to the ledge 18 in two different ways), efficient air flow performance for both exhaust and supply flow configurations is achieved, which is otherwise not achievable when using a switch to electrically reverse the direction of fan rotation. The fan housing 12 is attached to the ledge 18 such that the housing 12 is not obscured by the ledge 18. In other words, the fan housing 12, is not inserted into the 30 ledge 18, rather it is attached such that it is adjacent to the ledge 18. In other configurations, a small portion of the housing 12 may be inserted into, and/or surround, the ledge 18, whereby a substantial portion of the housing 12 remains unobscured by 4218227_1 (GHMaters) P89849.AU.1 - 13 the ledge. Both the ledge 18 and rims 36, 38 of fan housing 12 are shown being cylindrical in nature. This is primarily due to the path of rotation of the fan blades 26, and thus the shape of the fan housing. To assist with insertion into a sub-floor structure, such as a 5 brick wall, both the ledge 18 and rims 36, 38, are shown having two pairs of diametrically opposed flat edges 44/46, 48/50 and 52/54, respectively. Each flat edge 44/46, 48/50 and 52/54 enables a close facing relationship with the sub-floor structure when mounted thereto. In a brick wall, for example, three vertically adjacent bricks may need to be removed so that the sub-floor ventilator 10 can be substituted therefore. io The flat edges 44/46, 48/50 and 52/54 of the ledge 18 and rims 36, 38 can closely align with the remaining/surrounding bricks and avoid removal of more than 3 bricks. This is of particular relevance for sub-floor ventilator 10, as the rims 36, 38 and screw bosses 42 on the housing 12 result in a ventilator having a slightly increased cross-sectional area, when compared to other sub-floor ventilators. The flat edges 44/46, 48/50 and is 52/54 decrease the profile of the housing 12 and ledge 18 to enable substitution of the sub-floor ventilator 10 into cavities provided for existing sub-floor ventilators. This eliminates the need to enlarge the cavity for the insertion of the sub-floor ventilator 10 presently disclosed. As best shown in Figure 2C, each fan blade 26 comprises two flanges, in the 20 form of winglets 56, that extend from and along an outer (distal) edge of each blade 26. The winglets 56 can reduce the air's turbulence at the tip (or outer edge) of the fan blades. This reduces the amount of noise generated by the sub-floor ventilator 10 when the fan 24 is operating in either an exhaust or supply configuration. The motor unit 22 may be powered by either a direct or alternating current 25 power supply. The direct current source for the motor may employ voltages ranging from 5 to 100 volts (eg. 12, 24, 48 volt batteries etc). The alternating current source may employ voltages ranging from 100 to 415 volts (e. g. 110 or 240 volt mains power supply) and may employ single phase or three phase power supply. Use of direct current enables batteries and solar panels to provide power to the motor, whereas use of 30 alternating current enables a mains or grid electricity supply to provide power to the motor. Instead of electrical power, the motor may be air/pneumatically or even steam 4218227_1 (GHMaters) P89849.AU.1 - 14 driven, or may comprise an internal combustion engine or gas turbine etc. The motor unit 22 shown in Figures 1 to 4 utilises a direct current source. A cable 58 extends from the motor unit 22 to connect the motor to the power supply (not shown). The cable 58 is explained in more detail below, with reference to 5 Figure 4. One of the support arms 60 is provided with a channel 62 for feeding cable 58 to the motor unit 22, thereby connecting the motor unit 22 to a power source. Channel 62 aligns with a groove 64 in fan housing 12. Each rim 36/38 of the housing 12 comprises a groove 64, so that the cable 58 can be clear of the fan 24 when it is operating in either an exhaust or supply configuration. When operating in the exhaust 10 configuration, cable 58 can be fed from groove 64 on rim 36 to groove 64 on rim 38 to ensure that it does not impede the fan blades 26. As best shown in Figure 3, grille 16 is shown having a plurality of louvres 66 and a shroud 68. Each louvre 66 has a curved transverse profile (see Figures 3B and 3C). A louvre 66 having a curved profile reduces the air resistance that air flow 15 encounters as it moves through the ventilator 10. This curvature of the louvre 66 provides a gentle guiding of the oncoming air flow, which reduces flow losses through the reduction of turbulence and flow separation. This also reduces the amount noise generated by the ventilator 10. It can also reduce the power required for operation of the ventilator 10 for a given air flow rate. In-use, the curvature of each louvre 66 may 20 be concave facing downwardly (see Figures 3B and 3C). This profile prevents the ingress of rain into the ventilator 10. The air-permeable cover, or grille 16, is attached to ledge 18 such that the louvres 66 and shroud 68 project externally of the sub-floor structure. The shroud 68 surrounds the cavity created in the sub-floor structure (e.g. wall) to prevent water from 25 entering the ventilator. The shroud 68 may be mounted to the sub-floor structure in addition, or as an alternative to mount 14. In an alternative embodiment, the louvres and shroud may be located within or flush with the e.g. wall or wall cavity of the sub floor structure. Grille 16 is shown being integrally formed with ledge 18. This can reduce the 30 number of separate components required for sub-floor ventilation and can provide additional structural integrity to both the ledge 18 and the grille 16. The shroud 68 of grille 16 may be mounted to the outside of the sub-floor structure, whilst the ledge 18 4218227_1 (GHMaters) P89849.AU.1 - 15 may extend into the wall, wall cavity and/or the structure itself. A second cover, in the same form as grille 16 and mount 14, may be used to enclose the ventilator 10 on both sides of the fan housing 12. It may be fitted with a telescoping sleeve that can slip over the fan housing for attachment thereto. This allows 5 a flow-through arrangement for e.g. a wall, whilst only requiring the one type of cover. The telescoping sleeve allows for installation in walls of different depths/thickness. As both rims 36, 38 of housing 12 are configured to attach to grille 16, this enables a single type of grille to be manufactured and used on both sides of the ventilator 10, reducing production costs. 10 Referring now to Figure 4, the sub-floor ventilator 10 is shown attached to cable 58. The cable 58 is shown having three distinct portions 70, 72, 74. The first cable portion 70 attaches to the motor unit 22 at one end 76 and the second end is in the form of a plug 78. The second cable portion 72 comprises first and second connection ends in the form of sockets 80, 82. A control unit 84 is located in proximity to socket 82. 15 The third cable portion 74 comprises an end 86 for connection to a power source and the second end is in the form of a plug 88. Third cable portion 74 is also shown having a power transformer 75. Transformer 75 can modify or regulate the voltage and amperage provided to the motor, depending on the power supply. Plugs 78 and 88 are of the same type, and sockets 80, 82 are of the same type, allowing the location of the 20 control unit 84 to be changed by simply reversing the way the second cable portion 72 connects to the first and third cable portions 70, 74 respectively. When socket 80 of the second cable portion 72 is connected to the plug 78 of the first cable portion 70, and socket 82 of the second cable portion 72 is connected to the plug 88 of the third cable portion 74, the control unit 84 is located near the power supply (i.e. power point) of the 25 sub-floor ventilator 10. When these connections are reversed (i.e. when socket 80 of the second cable portion 72 is connected to the plug 88 of the third cable portion 74, and socket 82 of the second cable portion 72 is connected to the plug 78 of the first cable portion 70), the control unit 84 will be located near the motor unit 22 and fan 24. This allows a user to decide the best or most convenient location for the control unit. 30 For example, in some sub-floor structures it may be easier to access the power supply, so it is more convenient to have the control unit located in proximity to the power supply. In other sub-floor structures it may be easier to access the sub-floor ventilator, 4218227_1 (GHMaters) P89849.AU.1 - 16 so it would be more convenient to have the control unit located in proximity to the sub floor ventilator. Whilst not shown, the control unit may also comprise a sensor for sensing an environmental parameter in the sub-floor space. The sensor may sense for one or more of a variety of parameters which are indicative of the need to ventilate (or 5 increase the ventilation of) the sub-floor space. Where the control unit includes such a sensor, the ability to alter the location of the control unit can also enable the control unit to be placed in the most appropriate location for sensing the parameters of the sub-floor space. The alterable cabling provides flexibility for the installer and/or end user of the sub-floor ventilator, whilst providing a "universal" control cable, thus eliminating the 10 need to produce different cables and/or sub-floor ventilators for different uses. In this embodiment, the control unit 84 controls or varies the speed of the motor unit 22. The speed of the motor unit 22 controls the speed at which the fan 24, and thus fan blades 26, rotates. This alters how much exhaust, or supply, of air is provided. The speed of the fan 24 can therefore be altered depending on the prevailing conditions in 15 the sub-floor space. The control unit 84 can also comprise a sensor for automatic adjustment of the control unit 84. The sensor may sense the temperature, humidity, odour levels, or mould and fungus spore counts, present in the sub-floor structure. The sensor can also be used to automatically turn the motor on or off, depending on the prevailing conditions. 20 Whilst a number of specific sub-floor ventilator and ventilation system embodiments have been described, it should be appreciated that the sub-floor ventilator and ventilation system may be embodied in many other forms. In the claims which follow, and in the preceding description, except where the 25 context requires otherwise due to express language or necessary implication, the word "comprise" and variations such as "comprises" or "comprising" are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the sub-floor ventilator, grille and cabling as disclosed herein. 4218227_1 (GHMaters) P89849.AU.1

Claims (21)

1. A sub-floor ventilator comprising: - a mount for mounting to a sub-floor structure; - a housing for attachment to the mount, such that the housing remains 5 substantially unobscured by the mount when attached thereto; and - a fan for directing air flow, the fan located within the housing; wherein the housing is adapted for reversible attachment to the mount, such that the direction of airflow can be reversed.

2. A sub-floor ventilator as claimed in claim 1 wherein a series of peripheral 10 securing regions are provided around opposing respective ends of the housing which enable the housing to be reversibly secured to the mount.

3. A sub-floor ventilator as claimed in claim 1 or 2 further comprising an air permeable cover attached to the mount.

4. A sub-floor ventilator as claimed in claim 3, wherein the cover is integrally is formed with the mount.

5. A sub-floor ventilator as claimed in claim 3 or 4, further comprising a second air-permeable cover, the second cover configured to be attached to the housing on an opposite side of the housing to which the mount is attached.

6. A sub-floor ventilator as claimed in any one of the preceding claims wherein the 20 mount comprises at least one pair of diametrically opposed flat edges for providing a close facing relationship with the sub-floor structure when mounted thereto.

7. A sub-floor ventilator as claimed in claim 6 wherein the housing comprises at least one pair of diametrically opposed flat edges for providing a close facing relationship with the sub-floor structure when attached to the mount, and the mount is 25 mounted thereto.

8. A sub-floor ventilator as claimed in any one of the preceding claims wherein the housing further comprises a lip extending peripherally around an end of the housing, the lip having a diameter corresponding to the portion of the mount to which the housing is attached. 30

9. A sub-floor ventilator as claimed in claim 8, wherein each opposing end of the 7520311_1 (GHMatters) P89849.AU.1 SAMANTHA - 18 housing comprises a lip extending peripherally around an end of the housing, each lip having a diameter corresponding to the portion of the mount to which the housing is attached.

10. A sub-floor ventilator as claimed in any one of the preceding claims wherein the 5 fan is motor driven and comprises a cable to connect the motor to a power supply.

11. A sub-floor ventilator as claimed in claim 10 wherein the cable comprises a control unit for controlling the motor.

12. A sub-floor ventilator as claimed in claim 11 wherein the control unit further comprises a sensor for automatic adjustment of the control unit. 10

13. A sub-floor ventilator as claimed in claim 12 wherein the sensor senses the temperature, humidity, mould spore counts, fungal spore counts and/or odours of the sub-floor structure.

14. A sub-floor ventilator as claimed in any one of claims 11 to 13 wherein the control unit controls the speed of the motor. is

15. A sub-floor ventilation system for ventilating air from within, or into, a structure, the ventilation system comprising: - a motor-driven ventilator as claimed in claim 10, for mounting to the structure; - a controller for controlling the speed of the ventilator motor; and - a sensor for sensing at least one condition within the structure; 20 wherein the controller is adapted for controlling the speed of the ventilator motor in response to the or each condition sensed within the structure.

16. A sub-floor ventilation system as claimed in claim 15 wherein the at least one condition can include: temperature; humidity; mould spore count; fungal spore count; or odours. 25

17. A sub-floor ventilation system as claimed in claim 15 or 16 wherein the controller controls the speed of the motor.

18. A sub-floor ventilation system as claimed in any one of claims 15 to 17 wherein the controller is integrated with a cable connecting the motor to the power supply.

19. A sub-floor ventilator as claimed in any one of claims 11 to 14, or a sub-floor 7520311_1 (GHMatters) P89849.AU.1 SAMANTHA - 19 ventilation system as claimed in claim 18, wherein the cable comprises first, second and third distinct portions, the first cable portion attached to the motor at one end thereof and the second end thereof adapted for connection to the second cable portion, the second cable portion comprising a first connection end for connection to the second end 5 of the first cable portion and a second connection end, the third cable portion comprising an end for connection to the power source and the second end thereof adapted for connection to the second connection end of the second cable portion, wherein the controller is located in proximity to the second connection end of the second cable portion. 10

20. A sub-floor ventilator, or a sub-floor ventilation system, as claimed in claim 19 wherein the first and second connection ends of the second cable portion are of the same connection type, and the second ends of the first and third cable portions are adapted for connection with the same connection type.

21. A sub-floor ventilator, or a sub-floor ventilation system, as claimed in claim 20 1 wherein connection of the second cable portion to the first and third cable portions is reversible. 7520311_1 (GHMatters) P89849.AU.1 SAMANTHA