Ventilation arrangements

Abstract

A louvre arrangement for a ventilation arrangement. The louvre arrangement defining a plurality of passages into a housing. The passages extending generally upwardly inwards, and having an upper concave surface to urge air passing therethrough to turn inwardly and downwardly.

1 .- 40 . (canceled) 
     
     
         41 . A ventilation arrangement for ventilating a building interior, the ventilation arrangement comprising: an air duct which extends in use from roof level into an interior of the building to be ventilated to convey air between the exterior and interior of the building; ventilation openings which extend around an upper part of the air duct to direct moving air caused by wind movement into or out of the air duct; the ventilation openings having a louvre configuration defining a plurality of discrete passages, one above each other; the louvre configuration being configured such that each passage extends from the exterior into the ventilation arrangement; the passage extending generally upwardly inwards to avoid the ingression of liquids and other precipitation; with an upper surface of the passage being concavely curved to urge downwardly air entering through the passage from outside, and a lower surface of an inner part of the passage being concavely curved to urge upwardly air entering through the passage from outside to accelerate air entering through the passage. 
     
     
         42 . A ventilation arrangement according to  claim 41 , in which the passage extends upwardly, and at an inclination of between 20 and 40°. 
     
     
         43 . A ventilation arrangement according to  claim 41 , in which the upper surface of an inner part of the passage is concavely curved, which upper surface of the inner part of the passage may extend inwardly for a distance of between 35 and 60 mm, and may extend inwardly for a distance of between 40 and 50 mm. 
     
     
         44 . A ventilation arrangement according to  claim 43 , in which the curved upper surface of the inner part of the passage has a radius of between 55 and 65 mm. 
     
     
         45 . A ventilation arrangement according to  claim 41 , in which the upper surface of an outer part of the passage is concavely curved, which upper surface of the outer part of the passage may extend inwardly for a distance of between 35 and 60 mm, and may extend inwardly for a distance of between 40 and 50 mm. 
     
     
         46 . A ventilation arrangement according to  claim 45 , in which the curved upper surface of the outer part of the passage has a radius of between 30 and 50 mm, and may have a radius of between 35 and 45 mm. 
     
     
         47 . A ventilation arrangement according to  claim 45 , in which the outermost part of the upper surface of the outer part of the passage extends substantially vertically. 
     
     
         48 . A ventilation arrangement according to  claim 41 , in which the lower surface of the inner part of the passage has a radius of between 35 and 45 mm. 
     
     
         49 . A ventilation arrangement according to  claim 41 , in which the mouth of the ventilation opening is between 30 and 70 mm wide, and may be between 40 and 60 mm wide, and may be between 45 and 55 mm wide. 
     
     
         50 . A ventilation arrangement according to  claim 41 , in which the louvre configuration is active so as to selectively partially or wholly close the passages. 
     
     
         51 . A ventilation arrangement according to  claim 50 , in which the louvre configuration comprises a plurality of movable first components and static second components, with the first components being simultaneously movable with each other, with each passage being defined between a respective pair of first components and a respective pair of second components, which first components may be moveable over a distance of 40 and 70 mm between fully open and fully close positions, and may be moveable over a distance of 50 and 60 mm between fully open and fully close positions. 
     
     
         52 . A ventilation arrangement according to  claim 51 , in which the first components each extend vertically for between 40 and 70 mm, and may extend vertically for between 50 and 60 mm. 
     
     
         53 . A ventilation arrangement according to  claim 51 , in which the second components define an outer part of the passage when open, with the first components defining an inner part of the passage, which first components may have concave upper and lower surfaces. 
     
     
         54 . A ventilation arrangement according to  claim 51 , in which the underside of the second components, at least at an outer part thereof, is concave. 
     
     
         55 . A ventilation arrangement according to  claim 54 , in which the degree of concavity of the second components is greater than that of the first components. 
     
     
         56 . A ventilation arrangement according to  claim 51 , in which a substantially vertical downwardly facing slot is provided in the first components towards the external side thereof, which slot is slidingly locatable over a formation on a respective second component, such that when the slot is fully located over the formation the passage is fully open, and as the first components are moved relative to the second components the slot is moved off the formation causing closing of the respective passage. 
     
     
         57 . A ventilation arrangement according to  claim 56 , in which the slots each extend vertically for between 40 and 70 mm, and may extend vertically for between 50 and 60 mm. 
     
     
         58 . A ventilation arrangement according to  claim 56 , in which the formation on the second components is in the form of an upwardly extending flange provided on the inner edge of the second component. 
     
     
         59 . A ventilation arrangement according to  claim 51 , in which the ventilation arrangement is substantially polygonal in plan view, with first and second components for each side of the polygon, and the ventilation arrangement may be substantially rectangular in plan view. 
     
     
         60 . A ventilation arrangement according to  claim 51 , in which the movable first components are interconnected so as to be simultaneously movable, and link members may interconnect the first components, and a respective one of a plurality of link members may interconnect respective ends of the first components, which link members may be interconnected, and the link members may all be connected to an actuator member.