-1 The present invention relates to a ventilation hood for placing on a house roof.

Most usually a ventilation hood projects more or less vertically upwards from the roof of the house on which it is placed, for one thing so that it shall be parallel to a possible chimney and/or with the roof of the house, With known ventilation hoods this is aesthetically most attractive and as mentioned the most usual. A significant problem in that regard is, however, that by placing ventilation hoods on houses where ventilation hoods have previously not been found, or by replacing old hoods, the current angle of the roof must be measured before making the hood, some¬ thing which can be both bothersome and time-consuming. In order to evade the problem ventilation hoods have been employed which stand at right angles on the roof, thus forming an angle relative to the vertical chimney. These ventilation hoods have, however, not won particular acceptance, probably on the ground of the afore-mentioned aesthetic conditions that the hood is to be parallel to the chimney. Besides by placing such a hood on a steep roof there is a risk that melt water from snow which has piled up on the top side of the hood drains into the interior of the hood and downwards on the inner side and the outer side of ducts which project up into the ventilation hood.

Ventilation hoods are also known which are regulatable, so that they can be adjusted dependent upon the current angle of the roof. Thereby the need for measuring the angle of the roof disappears, but such hoods are relatively complicated and have not attained any particular acceptance on the market.

All known ventilation hoods have in common that they are placed above an excision in the roof, which one or more ventilation ducts are erected through. Steam which is brought up through the ventilation ducts will be condensed to a varying extent on the

under side of the roof of the hood and drip down through the opening, possibl so that it drips down in the ducts again or drains down them on the inside or the outside. The condensate can thereb drain or drip down into the insulation or on the floor of the loft and cause damage, or drain out through valves down into, for example, a bathroom which the duct forms an outlet from. It is clear that this is unfortunate, and that it can involve damage to the house after a certain time which is dependent upon the amount of condensate. There is thus a need for better solutions in this area, and the object of the present invention is to provide a ventilation hood which eliminates or reduces the disadvantages with known ventilation hoods de- scribed above.

This is achieved according to the invention with a ventilation hood which is characterised in that it comprises a) a substantially plate-shaped portion which is provided with one or more through-going pipe unions, for coupling air ducts below the plate-shaped portion, and b) a superstructure which is arranged on top of the plate-shaped portion above the pipe unions and the upper edge of which forms an angle with the plate-shaped portion. The invention will be further described in the following description having regard to the accompanying drawing, which illustrates a perspective view of a practial embodiment of the ventilation hood according to the invention. A ventilation hood 10 according to the invention comprises a substantially plate-shaped portion 11, which, however, at the upper end is designed with an elevated edge 12 which in a direction towards the lower end 13 of the plate becomes steadily lower. When the venti- la ion hood 10 is arranged on a roof, rain water which comes in on the plate portion will be prevented from draining out of it along the sides because of the edge

12 and draining towards the lower edge 13 of the plate portion. To the lower end of the plate-shaped portion 11 there is fixed a tongue 14 of flexible material, usually lead. This tongue is disposed over roof tiles or the like below the ventilation hood in order to prevent moisture from draining downwards on the under side of the rood tiles, in a corresponding manner as around a chimney.

On top of the plate-shaped portion 11 there is fixedly welded a superstructure 15, which in the illustrated embodiment is reminiscent in appearance of an attic of a house and the upper edge or top 16 of which forms an angle with the plate-shaped portion 11. The base surface of the superstructure on the plate-shaped portion 11 has the form of an equilateral triangle the sides of which are longer than the base line. At the lower end the superstructure has a wall 17 which by the plate-shaped portion is punched with a row of holes 18 at a small distance above the plate- shaped portion 11. The base line of the triangle extends parallel to the lower edge 13 of the plate- shaped portion 11. Within the superstructure 15 there project through the plate-shaped portion 11 two pipe unions 19a, 19b in the vicinity of the wall 17. To the pipe unions 19a, 19b there are coupled below the plate-shaped portion 11 ventilation ducts from bath, lavatory or thelike in the house. At the rear edge of the superstructure there is arranged a third pipe union 20, which likewise projects through the plate-shaped portion 11, and which below this is coupled to an air duct for the drainage system of the house. On placing the ventilation hood 10 on the house roof it is only necessary to cut out openings for the pipe unions in the roof boarding. That portion of the pipe union 20 which projects into the superstructure 15 is coupled to a pipe 21, which is led up towards the top 16 of the superstructure and which follows

this forwards towards the front edge of the super¬ structure, where it terminates inside a projection 22 on the superstructure. The projection 22, which forms a kind of storm hood, is open on the under side, and the opening is covered with, for example, netting.

End surface 23 of the projection forms with the plate- shaped portion 11 an angle which is different from the angle the wall 17 forms with the plate-shaped portion. If necessary condensate which is formed in the pipe 21 will thereby either drip out through the netting or down on to the plate-shaped member 11 within the attic 15 and from there drain out through the holes 18. Not any condensate will be able to drain out on the outside of the pipe 21 or the duct or down into the insulation in the loft. If necessary condensate from the air which comes up through the pipe unions 19a, 19b from the coupled ducts will almost exclusively drip down from the roof of the superstructure and down on the plate-shaped member 11, from which it will drain out through the holes 18. Not any condensate can drain down on the outside of the ducts, and that portion which drains down within the ducts will be little.

The ventilation hood according to the invention eliminates substantially completely the danger of water dripping or draining down into the insulation or onto the floor of the loft. By virtue of the design of the superstructure the impression will not be given of the ventilation hood standing obliquely relative to the chimney or roof, and an aesthetically attractive hood will be obtained independently of the angle of the roof. Thereby there is eliminated the previously dis¬ cussed problem of measuring the roof angle before production of the ventilation hood. Instead of allowing the top 16 to have the form of an edge this can also be rounded off, for example with a radius of curvature adapted to the radius of the pipe 21. Below on the wall 17 there can be arranged a gap which condensate can drain out through.