AU2013202386B2 - Ventilator - Google Patents

Abstract

A ventilator and ventilator system is disclosed. The ventilator comprises a motor driven rotor, and a stator for mounting to the structure. The rotor is rotatably mounted to the stator. The ventilator also comprises an annular support framework that extends 5 up and away from an upper periphery of the stator. The annular support framework comprises a plurality of air passageways arranged so as to enable the air to flow through the ventilator. The ventilator also comprises a cover that is supported on the annular support framework. The cover can provide the ventilator with the ability to allow sunlight into an enclosed space within the structure.

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): CSR Building Products Limited Invention Title: VENTILATOR The following statement is a full description of this invention, including the best method for performing it know to me/us: -2 VENTILATOR Technical Field A ventilator is disclosed for use in enclosed (e.g. roof) space ventilation. The 5 ventilator may take the form of an axial-flow fan ventilator, and may facilitate roof space cooling, and may also reduce moisture and/or condensation in the roof space. A system employing the ventilator is also disclosed. Background Art 10 Ventilators can be employed to evacuate air and other gases from enclosed spaces. Such enclosed spaces can include the roof space or interior of commercial and domestic buildings, shipping containers, portable buildings and sheds, ships etc. The air and other gases evacuated can include warm or heated gases, moist gases, gas containing contaminants such as contaminated air or toxic fumes, stale gases (especially 15 air) etc. A particular issue in domestic and commercial roof spaces can be the build-up of moisture therein, as a result of rising moisture from the underlying building, as well as rain and water ingress. At night, the air in the roof pace can cool and the moisture condenses, leading to damp, mould, fungal and associated moisture issues in the roof 20 space. Accordingly, automatic as well as selective ventilation of the roof space can be desirable. Combined ventilators and skylights, are disclosed in US 3396652 and GB880217. However, they are both quite bulky and cover a relatively large expanse of the roofline. 25 Ventilators may be wind-driven and/or motor-driven. In a wind- and/or motor driven rotor ventilator a rotor component can be provided that has a plurality of vanes or blades. In wind-driven rotor ventilators the vanes can be oriented in use to capture ambient wind to drive (rotate) the ventilator rotor, thereby causing air to be evacuated from the enclosed space (air adjacent to the vanes is forced outwardly by the rotating 30 vanes, and this air is in turn replaced by air from the enclosed space). In motor-driven rotor ventilators the rotor blades can be oriented in use to pump air from the enclosed space and through the ventilator. 4218283_1 (GHMatters) P89852.AU.1 -3 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 the art. The above references are also not intended to limit the application of the ventilator as disclosed herein. 5 Summary of Disclosure Disclosed herein is a ventilator. The ventilator can find particular, though not exclusive, application in the ventilation of enclosed spaces (e.g. roof spaces in buildings and warehouses in residential and commercial contexts, and enclosed spaces in portable 10 structures such as sheds, houses or ships), and reference herein to a 'roof-mounted ventilator' is intended to encompass such enclosed spaces. The ventilator may take the form of an axial-flow fan ventilator. The ventilator may facilitate roof space cooling, and may also reduce moisture and/or condensation in the enclosed space. In accordance with the disclosure the ventilator comprises a motor-driven 15 rotor. The rotor comprises one or more air-motive elements (e.g. fan blades or ventilator vanes). When the rotor rotates in use the air-motive element(s) can cause air within the structure to flow through the ventilator (e.g. pump air out of, or suck air into an enclosed space within the structure). The ventilator also comprises a stator for mounting to the structure. The rotor 20 is rotatably mounted to the stator (e.g. indirectly via a motor). The ventilator also comprises an annular support framework that extends up and away from an upper periphery of the stator. The annular support framework comprises a plurality of air passageways arranged so as to enable the air to flow through the ventilator. 25 The ventilator also comprises a cover formed from a material which is transmissive to light. The cover is configured so as to transmit light into the structure when the stator is mounted thereto. The cover is supported on the annular support framework. The cover can provide the ventilator with the ability to allow sunlight into an enclosed space within the structure (e.g. to provide for natural lighting in that space). 30 The transmission of light can also assist in the drying of damp or condensation within the enclosed space to reduce rot and mould. In addition, the transmission of light can reduce infestation risk from pests that require dark environments to breed or thrive. 4218283_1 (GHMatters) P89852.AU.1 -4 In addition, when the ventilator is installed on a roof line, etc, the use of a transparent (e.g. clear) cover can result in the perceived height of the ventilator being reduced, thereby improving the aesthetic appearance of the ventilator in use. Also, from a manufacturing perspective, use of a transparent (e.g. clear) cover means that the cover 5 need not be manufactured in different solid colours to match other parts of the ventilator. Further, as the cover is supported on the annular support framework, and thus extends beyond the stator (or so called 'throat'), the cover provides a larger light intake, or collection, area. This can increase the amount of light that is introduced into the structure when compared to known skylight ventilators, without the need for a bulky 10 ventilator and increased throat size. This support framework may also function to both space and support the cover with respect to the stator. Thus, the support framework can allow for air flow as well as supporting and e.g. prominently positioning the cover of the ventilator. In one embodiment the cover may be formed from a transparent material (e.g. a 15 clear plastic material such as a polycarbonate, an acrylate polymer, etc). In one embodiment the ventilator may be configured such that light is able to be transmitted into the structure between the rotor and the stator (e.g. there may be an increased extent of light passages/pathways between blades/vanes of the rotor and the stator). 20 In one embodiment the cover may be arranged so as to receive thereagainst the air flowing through the ventilator in a first general direction. The configuration of the cover may be such as to cause the air flow to change from the first to a second general direction. For example, the cover may have a configuration that facilitates or assists air flow directional change. In this regard, the cover may have a concave profile at its 25 underside. The shape and profile of the cover may be such that it is centred on a central axis of the ventilator. In this case, the air flow in the first general direction through the ventilator may generally be aligned with the central axis. Further, the air flow in the second general direction may generally be laterally away with respect to the central 30 axis. For example, the cover may be dome-shaped. Further, a central axis of the dome may be aligned with the ventilator central axis. In one embodiment the air passageways may be arranged at the rotor exhaust side and under the cover so as to enable the air flowing in the second general direction 4218283_1 (GHMatters) P89852.AU.1 -5 to pass out of the ventilator. When the cover is convex in profile (e.g. dome-shaped), the cover underside may extend out and down in-use to the one or more outlets. Reference herein to "exhaust side" is intended to indicate a normal mode of ventilator operation, wherein the ventilator is configured to exhaust (or pump out) air 5 from within the enclosed space of the structure. However, as will be described hereafter, the mode of operation of the ventilator can be reversed (or "inverted"), whereby the outlets may then become air inlets, and whereby the ventilator may then be configured to pump air into the enclosed space of the structure. In one embodiment the stator may further comprise a housing for the rotor. 10 The stator housing may, for example, have a generally cylindrical form. The stator housing may extend up from a base (e.g. having the form of a plate or flashing that can be secured to the structure, such as to a roof panel). In one embodiment the annular support framework may comprise a series of discretely spaced radial struts that extend up to the cover underside from the stator 15 upper periphery. These struts may extend radially from and around the ventilator central axis. The struts may be spaced whereby the air passageways take an elongate form, with the air passageways then extending between adjacent struts. In one embodiment a series of discretely spaced and generally parallel elongate louvres may extend between adjacent struts. Thus, each elongate air passageway may 20 be defined between (i.e. be bounded by) adjacent louvres and adjacent struts. In one embodiment each louvre may be provided with an aerodynamic profile. The profile may in use be oriented so as to better facilitate the flow of air the ventilator. In one form, their profile may be such that exhausting of air from within the structure is facilitated. In an alternative form, their profile may be such that the intake of air into 25 the structure is facilitated. In one embodiment each louvre may comprise leading and trailing edges extending therealong. Each such edge may be defined by opposed curved radii. These can improve the flow of air across each louvre (i.e. whether leaving or entering the ventilator). For example, the louvres may be oriented parallel with the oncoming air 30 flow, which can reduce their frontal area and thus resistance to the flow. This in turn can reduce flow losses. Furthermore by curving the shape of the louvres this helps to guide and distribute the air flow (e.g. to exhaust) to further reduce losses. 4218283_1 (GHMatters) P89852.AU.1 -6 In one embodiment the (or each) air-motive element may comprise a blade of the rotor, and each blade can be configured to pump air through the ventilator. It is conceivable that the rotor and ventilator can be designed whereby the rotor may solely or additionally be wind-driven, in which case each air-motive element may comprise a 5 vane of the rotor. In one embodiment the ventilator may further comprise a motor housing. The motor housing may enable the motor to be internally mounted with respect to the stator. In this regard, a base of the motor may be fixedly mountable to the motor housing. In one embodiment the motor housing may be configured such that it is able to 10 be inverted and re-mounted in the stator. Thus, the orientation of the rotor can be inverted. This enables the direction of air flow through the ventilator to be reversed. Thus, instead of the ventilator performing an exhaust function (i.e. removing air from the enclosed space of the structure), it may perform an aeration function (i.e. to ventilate, or draw fresh air into (i.e. from outside of the structure), the enclosed space of 15 the structure). In one embodiment the stator, or a housing of the stator, may comprise a number of internally located discrete mounts. In addition, the motor housing may comprise a number of corresponding discrete mounts at respective lower and upper peripheral edges of the motor housing. Thus, in one mode of use, the corresponding 20 mounts at the lower peripheral edge of the motor housing can engage with the stator mounts in one orientation of the motor housing within the stator. In another mode of use, the corresponding mounts at the upper peripheral edge of the motor housing can engage with the stator-mounts in an inverted orientation of the motor housing within the stator. 25 In one embodiment the stator-mounts may comprise a spaced series of upstanding pins (or screws or bolts) located internally of the stator. The motor housing mounts may then comprise a corresponding spaced series of pin-receipt sleeves (or screw- or bolt-bosses) located externally on and around the motor housing (i.e. the sleeves may receive the respective pins therein). 30 In one embodiment, a base of the motor is able to be fixedly mounted to the motor housing. In one embodiment, the motor for the rotor is an electric motor that may be mounted with respect to the stator by at least one support arm. A channel for an electric 4218283_1 (GHMatters) P89852.AU.1 -7 cable to connect to the motor can be provided in a given support arm. Thus, the support arm can provide both for support and for the feed of electrical power to the motor. In one embodiment a base of the motor may be mounted to the motor housing by the at least one support arm (e.g. by multiple, discretely spaced, radially extending 5 support arms, one of which is the given support arm with channel therein). The support arms can be spaced radially around a central axis of the ventilator, extending between the motor housing and a base of the motor (i.e. to fix and support the base in use). In one embodiment the channel may align with an opening in the motor housing. Further, the ventilator may be configured such that the electric cable can 10 extend through the opening in the motor housing and then through a space between the motor housing and the stator (e.g. in a groove in the motor housing). Thus, the cable may then lead out of the ventilator to a controller or power source. The configuration of the channel in the given support arm can also be such that the motor housing can be inverted and re-mounted without interfering with the electrical 15 cable. The motor-driven roof-mounted ventilator disclosed above may further comprise a cable for connecting the motor to a power supply. The cable may additionally comprise a control unit for controlling the motor. The cable may additionally comprise a sensor for automatic adjustment of the control unit. The cable 20 may be in the form of three distinct portions. The first cable portion may be connected to the motor at one end thereof and the second end may be adapted for connection to an end of 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 25 power source and the second end 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 end and the 30 control unit may be, for example, 1 - 50m. In this embodiment, the control unit may therefore be located near the motor of the ventilator. The connection ends of the second cable portion are preferably of the same connection type and the second ends of the first and third cable portions may be adapted 4218283_1 (GHMatters) P89852.AU.1 -8 for connection with the same connection type. This can allow the location of the control unit to be optionally altered between being located near the motor or near the power supply by reversing the orientation of the second cable portion. This allows a user or installer of the ventilator to locate the control unit at a convenient position. 5 In one embodiment an axis of the motor may be aligned on the ventilator central axis. Further, the motor axis may extend from the motor base to the rotor. Also disclosed herein is a ventilation system. The ventilation system comprises a motor-driven ventilator for mounting to a structure. For example, the 10 ventilation system may employ the ventilator as defined above. The ventilation system also comprises a controller for controlling the speed of the ventilator motor. The ventilation system further comprises a sensor for sensing at least one parameter within the structure. The sensed parameter may include temperature, humidity, carbon dioxide levels, mould spore counts, fungal spore counts, odour detection, or other parameters 15 which may be indicative of poor ventilation in a roof space. In accordance with the disclosure, the controller can be adapted for controlling the speed of the ventilator motor in response to the or each parameter sensed within the structure. For example, as the temperature rises the controller may adjust an output signal sent to the motor to increase the motor speed proportionally until a maximum 20 motor speed is reached. This can result in the motor only drawing as much power as needed e.g. to keep the enclosed space cool. This can also minimise noise emissions from the motor and rotor (e.g. fan). Thus, the system as disclosed herein is distinguished over prior art fixed speed systems that either run continuously or are simply switched on or off with a fixed speed by a thermostat switch. 25 In one embodiment the controller may be adapted for controlling the speed of the ventilator motor in a proportional relationship with the or each parameter sensed by the sensor. For example, the higher the sensed temperature of the enclosed space, the faster the motor speed is adjusted by the controller. The proportionality may be linear or it may comprise another modality (e.g. exponential response). 30 In one embodiment the sensor may be formed as unit with the controller (e.g. to be supplied and used as an integrated unit). In one embodiment the or each parameter sensed by the sensor can form an input signal to the controller. The controller may then be adapted to, in response and in 4218283_1 (GHMatters) P89852.AU.1 -9 proportion to the parameter input signal(s), output a control signal to the motor to control the motor speed. In one embodiment the controller may be disconnected (e.g. manually or automatically switched off) from the sensor. In this case, one or more fixed motor 5 speeds may be able to be set (e.g. a three-speed controller). In one embodiment the controller is located on (e.g. spliced into) an electrical cable that extends between a power source and the ventilator motor. The ventilator and cable may otherwise be as defined above. 10 Also disclosed herein is a combined sensor and speed controller unit. The unit can measure at least one parameter in the vicinity of a ventilator motor. Responsive to the or each measured parameter, the speed controller can be adapted for controlling the speed of the ventilator motor. This unit may be able to be retrofitted to existing (e.g. installed) systems, or it may form part of a ventilation system as set forth above. 15 In the unit the controller may be adapted for controlling the speed of the ventilator motor in a proportional relationship with the or each parameter sensed by the sensor (e.g. by pre-wiring or pre-programming the proportional relationship into a control circuit or micro-processor of the unit). In the unit the controller may be adapted for disconnection (e.g. by switching) from the sensor. In this case, one or more fixed 20 motor speeds may be able to be set in the unit (e.g. via a switch or control-dial). The speed controller may be otherwise as defined above. Brief Description of Drawings Notwithstanding any other forms that may fall within the scope of the 25 ventilator and system as set forth in the Summary, specific embodiments of the ventilator and system will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a perspective view of a first ventilator embodiment with a transparent dome-shaped cover mounted thereto; 30 Figure 2 shows a side sectional view through the ventilator of Figure 1, showing an exhaust flow configuration; Figure 3 shows a side sectional view through the ventilator of Figure 1, showing a reversed flow configuration; 4218283_1 (GHMatters) P89852.AU.1 -10 Figure 4A shows the same view as Figure 2 but annotated so as to enable a detail C (Figure 4B) and a detail D (Figure 4C) of the ventilator to be illustrated; Figure 5 shows a different side sectional view through the ventilator of Figure 1, showing a cable path arrangement; 5 Figure 6 shows a perspective view of the first ventilator embodiment when installed on a roof; Figure 7 shows a schematic illustration of a ventilator system that enables speed control and temperature sensing; Figure 8 shows a detail of the schematic set-up of Figure 7. 10 Detailed Description of Specific Embodiments Referring firstly to Figures 1 to 6, an embodiment of a ventilator is shown in the form of a rooftop-mounted, axial-flow, fan ventilator 10. The fan ventilator 10 is specifically, though not exclusively, configured for roof space cooling and the reduction 15 of moisture/condensation in a roof space (e.g. to help reduce the cooling requirements of, and reduce condensation in, residential houses and certain commercial buildings). In one mode, the fan ventilator 10 can be used to cool a roof space on hot days via a temperature sensing variable speed control (described in detail below with reference to Figures 7 & 8). In another mode, the fan ventilator 10 can be set for 20 constant ventilation rates via three user-selectable fixed speeds (described below with reference to Figures 7 & 8). The constant ventilation mode can be useful for reducing moisture and condensation in roof spaces where response to temperature is not appropriate or applicable. The fan ventilator 10 comprises a rotor in the form of a motor-driven fan 12. 25 The motor-driven fan 12 comprises a motor unit 14 and a fan 16 axially connected to the motor unit. The fan 16 comprises one or more air-motive elements in the form of fan blades 18. When the fan 16 rotates in use the fan blades 18 cause air within a roof space S to be drawn (or "pumped") out from the space S in a first direction D 1 , with direction Di generally being parallel to a central axis A of the fan ventilator 10 (axial 30 flow fan). The fan blades 18 are shown having two flanges, in the form of a winglets 19, that extend from and along an outer (distal) edge of each blade 18. The winglets can assist in reducing air turbulence at the blade outer edge (i.e. tip), which can reduce 4218283_1 (GHMatters) P89852.AU.1 - 11 the amount of noise generated by the ventilator, by reducing the amount of air passing through the gap between the fan blade 26 outer edge and the motor housing 54. The fan ventilator 10 also comprises a stator in the form of an in-use fixed support structure 20. The support structure 20 can be rooftop-mounted to a roof R via a 5 base plate or flashing 22, as best shown in Figure 6 (e.g. the flashing 22 is bent to a corrugated roof structure and secured thereto by roof screws 23). The flashing 22 is in turn affixed (e.g. by screws 24) to the lower end of a cylindrical housing 26 of support structure 20. The fan 16 rotates in use with respect to the support structure 20. In accordance with the present disclosure, the support structure 20 further 10 comprises a cover in the form of a dome 30 which can be releasably connected via screws 31 to a frusto-conical dome support 32. The dome 30 and dome support 32 are connected to but spaced from the cylindrical housing 26 as described hereafter, and are centred on the central axis A of fan ventilator 10. Whilst the dome as shown is convex, having a concave underside surface 33, it can also be profiled to be flat or even concave 15 (i.e. with a convex underside surface). The dome 30 is transmissive to light and may, for example, be formed from a transparent (e.g. clear) material, such as a transparent polymer (e.g. polycarbonate, acrylate resin such as poly(methyl methacrylate) - trade name Perspex, etc). This provides the fan ventilator 10 with the ability to allow sunlight into the roof space to 20 provide roof space lighting. The transmission of light through dome 30 can also assist in the drying of damp or condensation within the roof space to reduce rot and mould. In addition, this transmission can reduce infestation risk from pests that require dark environments to breed or thrive. When the dome 30 is transparent (e.g. clear), and when installed on a roof line, 25 the perceived height of the fan ventilator 10 can be reduced, thereby improving the aesthetic appearance of the fan ventilator 10 in use. From a manufacturing perspective, use of a transparent (e.g. clear) dome 30 means that the dome need not be manufactured in different solid colours to match the other parts of the ventilator. In an exhaust mode of the ventilator 10, the dome 30 is arranged at an exhaust 30 side of the fan 12 so as to receive against its underside the air flowing in the first direction Di. The concave configuration of the underside of dome 30 is such as to cause the air flow to change from the first direction Di to a second direction D 2 , with 4218283_1 (GHMatters) P89852.AU.1 - 12 the second direction D 2 generally being laterally away from the central axis A of fan ventilator 10. One or more air passageways are provided in the form of downwardly directed elongate openings in the form of elongate passages 34 are located under and protected 5 by the dome 30 and dome support 32. The passages 34 are arranged at an exhaust side of the fan 12 (i.e. the exhaust side when fan 12 is configured to pump air out of the roof space). The passages 34 are defined with a supporting framework 36 that extends from the cylindrical housing 26 to the dome support 32 so as to enable the air flowing in the second general direction to pass out of the ventilator. The passages 34 are in the path of 10 airflow in the second direction D 2 . The supporting framework 36 thus provides for air flow out or into the fan ventilator 10 as well as supporting the dome 30 and dome support 32. Further, as the dome 30 and dome support 32 are supported on the supporting framework 36, they thus extend beyond the support structure 20 (or so called 'throat' of the ventilator), thereby providing a larger light intake, or collection, area. 15 This can increase the amount of light that is introduced into the structure when compared to known skylight ventilators. This supporting framework 36 may also function to both space and support the dome 30 and dome support 32 with respect to the support structure 20. Thus, the supporting framework 36 can allow for air flow as well as supporting and e.g. prominently positioning the dome 30 and dome support 32 of the 20 ventilator 10. The supporting framework 36 comprises a series of evenly spaced, radially extending (i.e. with respect to central axis A) struts 40 that extend up to an underside of the dome support 32. The struts 40 extend from an upper periphery of housing 26, adjacent to a curved peripheral lip 42 of the housing 26. The struts 40 may be integrally 25 formed (e.g. moulded with) the housing 26. The struts 40 are spaced whereby the passages 34 take an elongate form, with the passages 34 then extending between adjacent struts 40. The supporting framework 36 also comprises a series of discretely spaced and generally parallel elongate louvres 44 which extend between adjacent struts. Thus, each 30 passage 34 is defined between (i.e. bounded by) adjacent louvres 44 and adjacent struts 40. Each louvre 44 may extend right around the supporting framework 36 and, in such case, may extend through an aperture 46 defined in a given strut 40 (see detail C in Figure 4B). Additionally or alternatively, the louvres may only extend between 4218283_1 (GHMatters) P89852.AU.1 - 13 adjacent struts, or the louvres may be integrally moulded with the struts. Each louvre 44 is provided with an aerodynamic profile. The profile may in use be oriented to air flowing in the second direction so as to better facilitate the exhausting (or letting in) of air from (or to) the ventilator. The aerodynamic profiling can improve the performance 5 of the ventilator (e.g. for a given air flow, the overall power consumed by a ventilator motor may be reduced). In this regard, each louvre 44 comprises a leading edge 48 and a trailing edge 50 extending therealong. Each edge is defined by opposed curved radii (in Figure 4C these are indicated by arrows 51 at leading edge 48 and arrows 52 at trailing edge 50). 10 These edges and radii can further improve the flow of air across each louvre (i.e. whether leaving or entering the ventilator). The supporting framework 36 is configured such that the louvres 44 are oriented parallel with the oncoming air flow (second direction D 2 ). This reduces the louvre frontal area exposed to the airflow and thus reduces the resistance to flow, in turn reducing flow losses. Furthermore, the 15 aerodynamic shape of the louvres 44 helps to guide and distribute the air flow to exhaust, to further reduce losses. The fan ventilator 10 also comprises a motor housing 54 for housing the motor unit 14 and fan 16. The motor unit 14 and fan 16 are located in the motor housing 54 such that their common axis is aligned on the ventilator central axis. The motor housing 20 54 enables the motor unit 14 and fan 16 to be internally mounted with respect to the cylindrical housing 26. In this regard, a base 56 of the motor unit 14 is fixedly mounted to but spaced from the motor housing 54 via a number of discretely spaced, radially extending support arms 58. One of those arms 60 is modified for feeding an electric cable 62 to the motor unit 14, as will be explained below with reference to Figure 5. 25 The support arms 58, 60 are evenly spaced to extend radially with respect to the ventilator central axis. The motor housing 54 is configured for releasable internal mounting with respect to the support structure 20 and, specifically, with respect to the cylindrical housing 26. In this regard, the motor housing 54 is able to be inverted and re-mounted 30 in the cylindrical housing 26. Thus, the orientation of the fan 16 can be inverted, whereby the direction of air flow through the fan ventilator 10 can be reversed. Thus, instead of the fan 16 performing an exhaust function, it may perform an aeration function (e.g. to ventilate the roof space). 4218283_1 (GHMatters) P89852.AU.1 - 14 To enable inversion and re-mounting of the motor housing 54 in the cylindrical housing 26, the housing 26 comprises a number of internally located discrete mounts in the form of a spaced series of upstanding screws 64 (or pins) located internally of the housing 26. In addition, the motor housing comprises a number of corresponding 5 discrete mounts at respective lower and upper peripheral edges of the motor housing. In this regard, the motor housing mounts comprise a spaced series of screw bosses 66 (or pin-receipt sleeves) located externally on and around the motor housing lower peripheral edge, and a spaced series of screw bosses 68 (or pin-receipt sleeves) located externally on and around the motor housing upper peripheral edge. Depending on the 10 orientation (e.g. normal exhaust mode - Figure 2, or inverted roof space ventilation mode - Figure 3), the screw bosses 66 and 68 can receive their respective screws 64 therein, as shown in each of Figures 2 and 3. Referring now to Figures 1 and 5, when the motor unit 14 comprises an electrically-powered motor, one of the motor support arms 60 is provided with a 15 channel 70 for an electric cable 62 to connect to the motor unit 14, via an ergodynamically flattened cable head, in the form of a plug 71, thereby connecting the motor unit 14 to an electric power source. Thus, support arm 60 can provide both for support of motor unit 14 and for the feed of electrical power thereto. The channel 70 aligns with an opening 72 defined in (e.g. moulded into) a wall 20 of the motor housing 54. As shown in Figure 5, the electric cable 62 extends through the opening 72, then through a cable groove 74 formed in (e.g. moulded into) the motor housing 54, to enable the cable 62 to pass between the motor housing 54 and the cylindrical housing 26. The cable 62 then terminates at a cable connector 76. The channel 72 and groove 74 help the motor housing 54 be inverted and re-mounted 25 without the electrical cable interfering. The provision of groove 74 also allows for a much smaller gap between the motor housing 54 and cylindrical housing 26. In a normal exhaust mode of use of the fan ventilator 10 (Figures 1 and 2), air from the roof space is caused by the motor-driven fan 12 to be drawn into the fan ventilator 10 via a lower opening 80, with the air being drawn to flow past the fan 30 blades 18 of fan 16 in the first direction Di, with airflow lines being generally parallel to the central axis A (i.e. axial airflow), and until the air flow impinges on the dome underside surface 33. The air is then caused by pressure to flow out and down along underside surface 33 in the second direction D 2 (i.e. generally laterally away with 4218283_1 (GHMatters) P89852.AU.1 - 15 respect to the central axis A) until it reaches the elongate passages 34 and passes out of the ventilator under dome support 32. In an aeration mode of use of the fan ventilator 10 (Figure 3), air from the atmosphere surrounding a building is caused by the motor-driven fan 12 to be drawn 5 into the fan ventilator 10 via the elongate passages 34 and flows into the ventilator under the dome support 32 (in a direction generally opposite to the second direction

D

2 ). The air impinges towards a central apex of dome support 32, and then flows downwardly in the ventilator 10 towards the lower opening 80, being drawn to flow past the fan blades 18 of fan 16 (in a direction generally opposite to the first direction 10 D1). The air then passes into the roof space to ventilate the same. Referring now to Figures 7 and 8, a ventilation system 100 is shown. The ventilation system enables the fan ventilator 10 to operate in automatic, temperature sensing, variable speed control modalities. In this regard, in an automatic temperature sensing mode, the speed of the fan 16 of ventilator 10 can be increased (and thus the 15 airflow therethrough) in proportion to roof space temperature. The system 100 comprises e.g. the fan ventilator 10 of Figures I to 6, although it should be understood that the system is not limited to this particular ventilator. The system 100 also comprises a controller 102 for controlling the speed of the ventilator motor unit. The controller controls the speed of the ventilator motor unit in response to 20 the temperature sensed within the roof space. The system 100 further comprises a temperature sensor 104 for sensing temperature within the roof space. As described in detail below, the temperature sensor 104 is located within a housing unit 106 for the speed controller 102, in conjunction with control electronics (e.g. to be supplied and used as an integrated unit). However, the temperature sensor 25 104 may be supplied and used in a stand-alone mode, and may then be coupled electrically, electronically or by emf to the speed controller 102. The unit 106 may be able to be retrofitted to existing (e.g. installed) systems. The temperature sensor 104 outputs a control signal to the motor unit 14 relative to the measured temperature. For example, the output signal can switch on to run the 30 motor unit 14 and fan 16 at a low speed when e.g. roof space temperature reaches 30'C. As the temperature rises the speed controller 102 can be programmed to adjust the output signal proportionally to increase the speed proportionally until a maximum fan speed is reached at e.g. 45'C. For example, the higher the sensed temperature of the 4218283_1 (GHMatters) P89852.AU.1 -16 roof space, the faster the motor unit speed is adjusted by the controller 102. The proportionality between temperature and motor speed may be linear or it may comprise another modality (e.g. an exponential response). This control also means that the fan 16 is only drawing as much power as is 5 needed to keep the roof space cool, thereby also minimising noise emissions from the fan/blades. The system 100 thus stands in distinct contrast to existing fixed speed systems that either run continuously, or are simply switched on or off with a fixed speed by a thermostat switch. In another mode of use, the speed controller 102 may be disconnected (e.g. 10 manually or automatically switched off) from the temperature sensor 104. In this mode, one or more fixed motor speeds can then be set. For example, the unit 106 can be configured at a switch 110 to be switched between an automatic mode (speed controller 102 and temperature sensor 104 connected) and a manual mode. In the manual mode the switch 110 may be switched (moved) between one of, for example, three speeds of a 15 three-speed controller. While the speed controller 102 is disclosed in this embodiment as having three set speeds, the speed controller may comprise fewer, or more, than three set speeds. In the system 100 the unit 106 is located on (e.g. spliced into) an electrical cable comprising a long part 112 and a short part 114. The long cable part 112 can be 20 connected via a female connector 113 to a male connector 115 of a power supply cord 116 extending from a power supply 117 (e.g. a transformer). The power supply 117 is in turn connected to a mains power source via a plug 118. The short cable part 114 also connects via a female connector 120 to the male cable connector 76 located at the end of ventilator cable 62. 25 As also shown in Figure 8, the cable 112, 114 is fully reversible, with normal function still being maintained, in that female connector 113 can be connected to the male cable connector 76, and female connector 120 can be connected to the male connector 115. This reversibility can e.g. allow the unit 106 (e.g. with temperature sensor 104 therein) to be moved closer to or further from the fan ventilator 10. Also, 30 with the different lengths of cable parts 112, 114, flexibility in location of the temperature sensor 104 can be achieved. In the unit 106 the proportional relationship of temperature with speed may be pre-wired or pre-programmed (e.g. as part of a control circuit) into the unit. However, 4218283_1 (GHMatters) P89852.AU.1 -17 if a micro-processor is employed in the unit 106, the relationship may be able to be varied. The unit 106 may also be adapted to select (e.g. in a pre-programmed way or via a programmable switching) between the automatic and manual modes. The unit 106 may also be integrated as part of a larger cooling system for a building (e.g. to be 5 activated by that system). The power supply 117 is typically adapted to an alternating current source and may accommodate voltages ranging from e.g. 100 to 415 volts (e.g. 110 or 240 volt mains power supply). The power supply 117 may accommodate single phase or three phase power supply. The power supply 117 may also be adapted to direct current 10 supply (e.g. from batteries or solar panels). Components of the system may be able to be retro-fitted to known ventilators. Whilst specific embodiments of the ventilator and system have been described, it should be appreciated that the ventilator can be embodied in many other forms. 15 In the claims which follow, and in the preceding description, except where the 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 20 or addition of further features in various embodiments of the ventilator and system. 4218283_1 (GHMatters) P89852.AU.1

Claims (20)

1. A roof-mounted ventilator for ventilating air from within, or into, a structure, the ventilator comprising: - a motor-driven rotor comprising one or more air-motive elements which, 5 when the rotor rotates in use, cause air to flow through the ventilator; - a stator for mounting to the structure and to which the rotor is rotatably mounted; - an annular support framework, that extends up and away from an upper periphery of the stator, comprising a plurality of air passageways arranged so 10 as to enable the air to flow through the ventilator; and - a cover supported on the annular support framework, formed from a material which is transmissive to light, the cover being configured so as to transmit light into the structure when the stator is mounted thereto.

2. A ventilator as claimed in claim 1 wherein the cover has a concave profile that is 15 centred on a ventilator central axis, and with the cover underside extending out and down in-use to the annular support framework.

3. A ventilator as claimed in claim 1 or 2 wherein the annular support framework comprises a series of discretely spaced radial struts that extend up to the cover underside from the stator upper periphery, and radially from and around the ventilator 20 central axis, with the air passageways being elongate and extending between adjacent struts.

4. A ventilator as claimed in claim 3 wherein a series of discretely spaced and generally parallel elongate louvres extend between adjacent struts, with an elongate air passageway being defined between adjacent louvres and adjacent struts. 25

5. A ventilator as claimed in claim 4 wherein each louvre has an aerodynamic profile that in use is oriented to so as to facilitate the flow of air through the ventilator.

6. A ventilator as claimed in any one of the preceding claims further comprising a motor housing for enabling the motor to be internally mounted with respect to the stator, wherein the motor housing is configured such that it is able to be inverted and re 30 mounted in the stator whereby the orientation of the rotor is able to be inverted and thus the direction of air flow through the ventilator is able to be reversed. WInem11 7 1 1r:1~ f-1ei DnaQ a a 1 I I 1 - a -1R -19

7. A ventilator as claimed in claim 6 wherein the stator comprises a number of internally located discrete mounts, and wherein the motor housing comprises a number of corresponding discrete mounts at respective lower and upper peripheral edges of the motor housing, whereby the corresponding mounts at the lower peripheral edge of the 5 motor housing can engage with the stator-mounts in one orientation of the motor housing within the stator, and whereby the corresponding mounts at the upper peripheral edge of the motor housing can engage with the stator-mounts in an inverted orientation of the motor housing within the stator.

8. A ventilator as claimed in claim 7 wherein the stator-mounts comprise a spaced 10 series of upstanding pins located internally of the stator, and wherein the motor housing-mounts comprise a corresponding spaced series of pin-receipt sleeves located externally on and around the motor housing.

9. A ventilator as claimed in any one of the preceding claims, wherein the motor for the rotor is an electric motor that is mounted with respect to the stator by at least one 15 support arm, and wherein a channel for an electric cable to connect to the motor is provided in a given support arm.

10. A ventilator as claimed in claim 9, when dependent on any one of claims 6 to 8, wherein a base of the motor is mounted to the motor housing by the at least one support arm. 20

11. A ventilator as claimed in claim 10 wherein the channel aligns with an opening in the motor housing, whereby the electric cable can extend through the opening in the motor housing and through a space between the motor housing and the stator.

12. A ventilator as claimed in claim 10 or 11 wherein a series of discretely spaced radial support arms extend from the motor housing to the motor base, with the support 25 arms being spaced radially around a central axis of the ventilator, and with one of the series of support arms defining the given support arm with the channel for the electric cable.

13. A ventilator as claimed in any one of the preceding claims wherein the motor is connected to a power supply by a cable and wherein the cable comprises a control unit 30 for controlling the motor. nem11 7 1 Ir: -1 Ia Da ll I I Ifl - R - 20

14. A ventilator as claimed in claim 13 wherein the cable further comprises a sensor for automatic adjustment of the control unit.

15. A ventilator as claimed in claim 13 or 14 wherein the cable comprises first, second and third distinct portions, the first cable portion connected to the motor at one end 5 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 of the first cable portion and a second connection end, and 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, 10 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, and wherein the control unit is located in proximity to the first connection end of the second cable portion.

16. A ventilator as claimed in any one of the preceding claims wherein the cover is 15 arranged so as to receive thereagainst the air flowing through the ventilator in a first general direction, the configuration of the cover being such as to cause the air flow to change from the first to a second general direction.

17. A ventilation system for ventilating air from within, or into, a structure, the ventilation system comprising: 20 - the roof-mounted ventilator, as claimed in any one of the preceding claims, for mounting to the structure; - a controller for controlling the speed of the ventilator motor; - a sensor for sensing at least one parameter within the structure; wherein the controller is adapted for controlling the speed of the ventilator 25 motor in response to the or each parameter sensed within the structure.

18. A ventilation system as claimed in claim 17 wherein the controller is adapted for controlling the speed of the ventilator motor in a proportional relationship with the or each parameter sensed by the sensor.

19. A ventilation system as claimed in claim 17 or 18 wherein the or each parameter 30 sensed by the sensor forms an input signal to the controller, and wherein the controller is adapted to, in response and in proportion to the or each parameter input signal, output a control signal to the motor to control the motor speed. WInem11 7 1 Ir:1-1mei DnaQ a a 1 I I 1 - a -1R -21

20. A ventilation system as claimed in any one of claims 17 to 19 wherein the controller is adapted for disconnection from the sensor, and whereby one or more fixed motor speeds can be set. nc7,117 1 Ir: f-iitr a ll nI1 I IAIlA -IR