AU2006246303B2

AU2006246303B2 - Vent and grilles

Info

Publication number: AU2006246303B2
Application number: AU2006246303A
Authority: AU
Inventors: Bill Hendricks; Allan Pearce
Original assignee: ADVANTEC AUSTRALASIA Pty Ltd
Current assignee: ADVANTEC AUSTRALASIA PTY Ltd
Priority date: 2005-05-12
Filing date: 2006-05-12
Publication date: 2013-03-21
Anticipated expiration: 2026-05-12
Also published as: AU2006246303A1

Abstract

A fan assembly including a casing (10) which is generally cylindrical in form and which has located therein a fan motor and fan blades including a casing which is generally cylindrical in form and which has located therein a fan motor and fan blades whereby air can be drawn into the casing, and delivered there from, and having a grille (30) extending over an open end of the casing. The grille has a plurality of angular curved blades (34) extending from a central portion (33) thereof to the periphery. These blades are preferably at an angle to the normal plane through the grille whereby inlet air into the casing is caused to move to, the fan blades at and angle which permits efficient operation of the fan.

Description

WO 2006/119564 PCT/AU2006/000612 1 VENT AND GRILLES Technical Area This invention relates to a vent and grille and, in particular, to a vent and grille which can be used in association with a fan to draw air from an area. Background to the Invention it is well-known to provide fans which can remove air from an area, and particularly, for use in kitchens, bathrooms or the like, where they are called exhaust fans. Most such fans used in Australia are located in an aperture in the ceiling, have a grille extending into the room and a fan mounted thereabove. In some applications, and in many applications overseas, the fan may be IdCated in a casing and connected to an exhaust duct whereby the air removed is delivered to the exterior of the building in which the fan is located.

WO 2006/119564 PCT/AU2006/000612 2 Outline of the Invention It is the object of the present invention to provide a fan and grille and a grille arrangements for fans for use in such applications. The invention, in one sense, provides a fan assembly including a casing Which is generally cylindrical in form and which has located therein a fan motor and fan blades whereby air can be drawn into the casing, and delivered therefrorj, and having a grille extending over an open end of the casing. It is preferred that the grille has a plurality of angular curved blades extending from a central portion thereof to the periphery. These blades are preferably at an angle to the normal plane through the grille whereby inlet air into the casing is caused to move to the fan blades at and angle which permits efficient operation of the fan. In some applications the down-stream end of the casing is provided with a connector whereby duct-work can be connected thereto. It is preferred that there .is a flap-valve or the like whereby any passage of air through the casing, particularly from the down stream side, is normally restricted, but which, on operation of the fan, opens to permit relatively unrestricted flow of WO 2006/119564 PCT/AU2006/000612 3 air through the casing. The invention also provides a grille for a fan assembly including a casing Which is generally cylindrical in form and which has located therein a fan motor and fan blades whereby air can be drawn within the casing and having a plurality of angular curved blades extending from a central portion thereof to the periphery. The angular curved blades of the grille are at an angle to the normal through the grille. .Description of an Embodiment of the invention In order that the invention may be more readily understood, we shall describe one particular embodiment in relation to the accompanying drawings, in Which: Fig 1 shows a perspective view from beneath the assembly; Fig 2 shows a perspective view from above the assembly; Fig 3 shows a side elevation of the assembly; Fig 4 shows a perspective view into the casing, with the fan remoVed; Fig 5 shows an underneath view of the grille. In this embodiment we have a casing 10 which, over a major part of its length 11, is fustoconical in form and which has at its lower (by definition the portion which WO 2006/119564 PCT/AU2006/000612 4 would extend into a room or the like) end an outwardly directed flange 12 which can serve as a stop against an aperture in the ceiling or wall, into whi6h the device is to be located. At its inner end 20 (the opposite end) the casing may have a cylindrical portion to which a duct may be connected or which may be free. Mounted in the body of the casing there is a fan motor and fan blades, not shown but the mount for this is shown as 15 in Fig 2 which, on operation, can draw air through the casing. Located in the inner end 20, there is a flap valve 21 or the like which is biased to be normally closed, the position illustrated in Fig 3. The flap valve has a shaft 22, which may be moulded integral therewith and rotatably mounted diredty or indirectly to a bearing in a member 23 which is connected to supports 24 moulded into the casing. The biasing of the flap valve either being by the shaft thereof being slightly off-centre or by the addition of a bias weight. The flap valve rests against a stop means 25 connected to a side wall of the casing on one side of the casing to restrict movement in that direction. At the open end of the casing, and connected to the flange 12 we provide a grille 30 which has an outer annular portion 31 which can be of a diameter greater than the diameter of the flange 12 of the casing. Clips 32 are provided to connect WO 2006/119564 PCT/AU2006/000612 5 the grille 30 to the flange 12. The grille has, extending from the centre thereof 33 to the annular portion 81, a plurality of ribs 34. These ribs are each identical in form and are curved somewhat intd the appearance of a turbine blade,. that is, over most of their length they are displaced from a radius from the centre 33 to the point of their connection an the annular portion. That is, they are formed away from the radius, and then back to the radius. In section, as can be seen from Fig 1, they lie effectively at an angle t6 the normal plane of the annular portion which includes the centre of the grille and the point of connection of the rib to the annular portion by an amount which Varies from a minimum at the centre, where they can effectively be normal to the plane, to a maximum at the point of connection to the annular portion. As mentioned, the grille can be removably connected to the flange 12 of the casing so that it can be removed for cleaning and so that access can be obtained to the fan and fan motor and it also may be provided with clips which can retain the assembly in an aperture in the ceiling, wall, or the like. The annular portion 12 may have upwardly extending lugs, having an outwardly WO 2006/119564 PCT/AU2006/000612 6 -directed portion adjacent their end away from the surface of the annular member which can act as clips to connect the grille to the casing. In use, the assembly may be passed through an aperture in a ceiling or wall And, depending upon the ceiling space, the fan may be wired before location or afterwards, and the clips 35 around the periphery retain the assembly in position. It may be preferred that this location be effected before the grille 30 is connected and, once located, the grille can be connected to the flange 12 of the casing. In use, when the fan is operated, the flap valve 21, as described earlier, will open to provide little resistance to the through movement of the air. The particular formation of the grille 30 has two main benefits over previous grilles. Firstly, because of the angular location of the ribs 34, from many positions, the fact that the grille is open cannot be seen and, from other positions, the degree of the exposure of the grille is only relatively minor. This is desirable aesthetically as more conventional grilles tend to be unsightly and, particularly when they have been In use for any period, particularly in kitchens, tend to get a buildup of fat and soot and this can be unsightly.

WO 2006/119564 PCT/AU2006/000612 7 The other aspect of the grille is that the formation of the ribs 34 is such that air, when drawn into the casing, is caused to effectively rotate about the central axis of the casing and this moving column of air is drawn through the fan and strikes the fan blades at an optimal angle to permit effective delivery of the air through the casing -10 to the exterior or to the ducting. At the same time, because the air is already moving prior to striking the fan blades, there tends to be a reduction in noise when the air passes therethrough. It-will be seen that the fan and casing and grille of the invention provides an assembly which is aesthetically pleasing, the grille can be readily removed for cleaning and the transmission of air through the grille into the casing and therefrom is efficient and quiet. The particular formation of the blades in the grille may be varied, as may be the construction of the casing and the flat valve, if provided, without departing from the spirit and scope of the invention.

Claims

2. A fan assembly as claimed in claim 1, wherein the fan assembly further L5 includes a valve at an inner end of the casing opposite to the open end, the valve for restricting flow of air from the downstream side but permitting relatively unrestricted flow through the grille through the casing.
3. A fan assembly as claimed in claim 2, wherein the valve is biased to a 20 closed position.
4. A fan assembly as claimed in any preceding claim, wherein the downstream end of the casing is provided with a connector whereby duct-work can be connected thereto,
5. A fan assembly as claimed in any preceding claim, wherein the valve is 25 rotatable and in the closed position rests on a stop means connected to a side wall of the casing. 9
6. A fan assembly as claimed in Claim 2, 3 or 5, wherein the valve is a flap valve biased to a closed position by a bias weight.
7. A fan assembly as claimed in any one of the preceding claims, wherein each blade of the plurality of blades is identical in form. 5 8. A fan assembly as claimed in any one of the preceding claims, wherein each blade of the plurality of blades over most of its length is displaced from a radius from the centre to the point of its connection on the annular peripheral portion where it returns to the radius.
9. A fan assembly as claimed in any one of the preceding claims, wherein 10 the casing over a major part of its length is frustoconical in form.
10. A fan assembly as claimed in any one of the preceding claims, wherein the open end has an outwardly extending flange which can serve as a stop against an aperture in a ceiling or wall.
11. A fan assembly as claimed in Claim 10, wherein pivotal clips vertically [5 spaced from an upper side of the flange are adapted to attach the fan assembly to the ceiling or wall.
12. A fan assembly as claimed in Claim 10 or 11, wherein the fan assembly has clips to connect the grille to the flange.