NL2028446B1

NL2028446B1 - Ventilation assembly

Info

Publication number: NL2028446B1
Application number: NL2028446A
Authority: NL
Inventors: Johannes Jacobus Gerardus Egging Jurgen
Original assignee: Ubbink Bv
Priority date: 2021-06-14
Filing date: 2021-06-14
Publication date: 2022-12-21

Abstract

The invention relates tx) a ventilation assembly for the passage of gasses through. a roof, comprising' an outlet head that comprises a bottom wall, a top wall, and a back wall that define an inlet opening, an outlet opening 5 and a stream. chamber, wherein the inlet opening has a central axis, and the outlet head has a first plane that extends through the back wall, and a second plane transverse to the first plane, wherein the back wall extends at a first side of the second plane and the outlet 10 opening extends at least at an opposite second side of the second. plane, wherein. the outlet head. comprises multiple lamellae that comprise a base blade and a raised portion, wherein the base blade is convex towards the top wall parallel to the first plane or the second plane, and the 15 raised portion is raised towards the top wall.

Description

P139550NL00 Ventilation assembly

BACKGROUND The invention relates to a ventilation assembly for the passage of gasses through a roof. Known ventilation assemblies comprise a duct that extends through the roof and a ventilation head above the roof that prevents rain from entering the ventilation assembly. The duct is connected to a ventilation system that is located below the roof.

SUMMARY OF THE INVENTION There is a need for ventilation assemblies that do not protrude far above a roof. A known ventilation assembly that does not protrude far above the roof comprises a ventilation head that comprises a top wall, a back wall, two side walls and an outlet opening opposite to the back wall having a grid therein. The back wall is orientated upwards on the roof facing the top of the sloping roof. The top wall, back wall, and side walls prevents rain from entering the ventilation assembly and guide the passing gasses towards and through the outlet opening. The outlet opening is orientated downwards facing the bottom of the roof and the gasses are therewith exhausted from the ventilation assembly downwards along the roof. A disadvantage of the known ventilation assembly is that the configuration of the outlet head causes substantial pressure losses to the ventilation system.

It is an object of the present invention to provide a ventilation assembly that does not protrude far above the roof and that has acceptable pressure losses for the intended application.

According to a first aspect, the invention provides a ventilation assembly for the passage of gasses through a roof, comprising an outlet head that comprises a base having a bottom wall and an inlet opening to receive gasses to be exhausted, a top cover having a top wall above the bottom wall, and a back wall that extends between the bottom wall and the top wall, wherein the base, the top cover and the back wall define an outlet opening and a stream chamber between the inlet opening and the outlet opening for the received gasses, wherein the inlet opening has a central axis, and the outlet head has a notional first plane that contains the central axis and that extends through the back wall, and a notional second plane that contains the central axis and that is transverse to the first plane, wherein the back wall extends at a first side of the second plane and the outlet opening extends at least at an opposite second side of the second plane, wherein the outlet head comprises multiple lamellae that extend in the outlet opening to define multiple slits in the outlet opening, and wherein the lamellae comprise a base blade and a raised portion that forms a continuation of the base blade that faces the central axis, wherein the base blade is convex towards the top cover parallel to the first plane or the second plane of the outlet head, and the raised portion is raised towards the top cover with respect to the base blade.

In an embodiment the outlet opening extends through the first plane and through the second plane at both opposite sides of the first plane. The outlet opening covers more than half of the outline of the outlet head when viewed along the central axis.

The convex shape of the base blade of the lamellae in combination with the rain-impact resistant raised portion reduce or prevent rain blown by wind from entering through the outlet opening into the outlet head. This provides the conditions to increase the area of the outlet opening having the lamellae, while retaining protection against rain entering the ventilation assembly. The area of the outlet opening may be increased to cover a greater part of the outline of the outlet head when viewed along the central axis. When the outlet opening has a greater area this results in low pressure losses. As the shape and configuration of the lamellae adds little drag or friction to the exhausted gasses, the outlet head having the lamellae has low and acceptable overall pressure losses for the intended application.

The convex shape of the base blade in combination with the raised portion further ensures that any condensation flows to the outside of the lamellae. The run- off condensation of the lamellae can be collected in a receptacle in the base and can then be drained towards the roof through drain holes.

In an embodiment the bottom wall and/or the top cover merge into the back wall to form the back wall.

The outlet head can be orientated with the back wall facing a predominant airflow direction to which the outlet head is exposed. In this manner the back wall can further reduce or prevent rain blown by wind from entering through the outlet opening into the outlet head.

In an embodiment the outlet head has a boxed shape, wherein the top wall and the bottom wall extend transverse to the central axis and have, when viewed along the central axis, a trapezoid outline. The back wall extends between the smaller base of the trapezoid shaped top wall and bottom wall of the outlet head. The front of the outlet head is wider as compared to the back wall to provide a bigger outlet opening for the exhausted gasses to further reduce pressure losses in the outlet head.

In an embodiment the lamellae extend around the central axis and the inlet opening to form a continuous unit around the central axis, wherein the base blade and the raised portion extend circumferentially around the central axis. The continuous lamellae reduce or prevent rain blown by wind from entering through the outlet opening from multiple directions. The continuous lamellae furthermore are more rigid and provide a more solid framework to the outlet head.

In an embodiment the lamellae form separate units that are stacked onto each other. The stacked lamellae form a circumferential grid around and substantially parallel to the central axis between the top cover and the base. The grid is rigid and provide a solid framework to the outlet head.

In an embodiment the base comprises multiple columns that extend parallel to the central axis towards the top cover, and the lamellae comprise multiple respective column passages through which the respective columns extend, wherein the columns and the column passages are arranged in a quadrilateral arrangement when viewed along the central axis. The columns extend between and space apart the bottom wall and the top wall and provide rigidity to the outlet head. Furthermore the columns provide a framework to which the lamellae can be attached and that provides additional rigidity to the lamellae.

In an embodiment the lamellae comprise column collars that determine the column passages and that space apart the lamellae along the central axis. The stacked column collars provides additional rigidity to the lamellae and the ventilation head.

In an embodiment the lamellae are identical to each other so that the lamellae can be produced in a straightforward and economically favorable manner.

In an embodiment the base is convex towards the top cover parallel to the lamellae, having its apex in the first plane. In an embodiment the top cover is convex away from the base parallel to the lamellae, having its apex in the first plane. In an embodiment the base defines a receptacle around the inlet opening for receiving fluids, and a drain hole for discharging received fluids from the receptacle. The convex shape of the top cover ensures that 5 condensation from the exhausted gasses on the top cover flows to the sides thereof. The condensation can drip downwards into the receptacle together with the condensation that runs of from the lamellae and then be drained from the outlet head through the drain hole.

In an embodiment the ventilation assembly comprises a connector duct that comprises a first end portion that, in a mounted state of the ventilation assembly, protrudes above the roof, and a second end portion below the roof that is configured to be mounted to an end portion of a ventilation duct, wherein the base of the outlet head is configured to be mounted to the first end portion of the connector duct such that, in the mounted state of the ventilation assembly, the inlet opening is aligned with the connector duct. The connector duct provides a roof passage for the exhausted gasses and straightforward manner to connect the outlet head to a ventilation system that is located below the roof inside a building.

In an embodiment the ventilation assembly comprises a placement part that is configured to connect the ventilation assembly to the roof, wherein in the mounted state of the ventilation assembly the placement part is clamped between the base of the inlet head and the first end portion of the connector duct. The placement part can be integrated in the roof for connecting the ventilation assembly weatherproof to the roof.

In an embodiment the outlet head, the connector duct and the placement part comprise corresponding indexes to, in the mounted state of the ventilation assembly, fixate the outlet head, the connector duct and the placement part with respect to each other in a rotation direction around the central axis. The indices prevent the connector duct from rotating around the central axis with respect to the outlet head and/or to the placement part.

In an embodiment, in the mounted state of the ventilation assembly, the central axis extends transverse to the roof. In an embodiment the connector duct comprises at the second end portion an integrated fastener that is configured to fixate the ventilation duct to the connector duct in a direction parallel to the central axis. In a further embodiment thereof the fastener comprises a cable tie. The transverse orientation and the integrated fastener make mounting the ventilation unit to the roof more straightforward. The cable tie is a well-known fastener that is robust and economically favorable In an embodiment, when the main roof surface is sloped, the back wall is orientated slope upwards and the outlet opening is at least orientated slope downwards. In this way the back wall covers the outlet head for strong airflows that pass downwards along the roof and prevents rain or water from being blown into the outlet head from that direction.

The various aspects and features described and shown in the specification can be applied, individually, wherever possible. These individual aspects, in particular the aspects and features described in the attached dependent claims, can be made subject of divisional patent applications.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be elucidated on the basis of an exemplary embodiment shown in the attached drawings, in which: Figure 1A is an isometric view of a ventilation assembly comprising an outlet head according to the invention; Figure 1B is an isometric exploded view of the

: ventilation assembly of figure 1; Figures ZA-C are a front view, a side view and a top view of the ventilation assembly respectively; Figure 3 is a side section view of the ventilation assembly that is installed on a roof.

DETAILED DESCRIPTION OF THE INVENTION Figures 1A-B, 2A-C and 3 show a ventilation assembly 1 for the passage of gasses through a roof 2, in particular for the discharge of ventilation air that is drawn from the interior of a building through the roof 2. The ventilation assembly 1 comprises a covering part or placement part 10 that can be integrated in the roof 2 for connecting the ventilation assembly 1 weatherproof to the roof 2. The ventilation assembly 1 comprises an outlet head 50 above the roof 2, and a tubular connector duct 20 for connecting the outlet head 50 to the placement part 10 and to a not shown ventilation duct below the roof 2. When the ventilation assembly 1 is installed on the roof 2, the connector duct 20 and the outlet head 50 define a channel 3 that extends through the roof 2 and that has a central axis Z that is orientated substantially transverse to the plane of the main surface of the roof 2. The outlet head 50 has a longitudinal notional first plane or plane of symmetry XZ that contains the central axis Z, and a notional second plane or datum plane YZ that contains the central axis Z and that is transverse to the plane of symmetry XZ. As best shown in figures 1B and 3, the outlet head 50 comprises a base 51 having a bottom wall 56 and a circular inlet opening 54, having the central axis Z, to receive gasses to be exhausted. The outlet head 50 comprises a top cover 70 having a top wall 73 parallel above and spaced apart from the bottom wall 56, and a back wall 52 that extends between the bottom wall 56 and the top wall 73. The base 51, the top cover 70 and the back wall 52 define an outlet opening 72 for the received gasses and a stream chamber 65 for the received gasses between the inlet opening 54 and the outlet opening 72. The outlet head 50 comprises multiple identical stacked lamellae 80 that extend in the outlet opening 72 to define multiple slits 81 between the base 51 and top cover 70 in the outlet opening

72.

In this example, the outlet head 50 is substantially box shaped. The top wall 73 of the top cover 70 extends substantially transverse to the central axis Z and the bottom wall 56 of the base 50 extends substantially parallel to the top wall 73 to form the top and bottom of the box shaped outlet head 50. The top wall 73 and the bottom wall 56 have a substantially symmetrical trapezoid shape or outline when viewed along the central axis Z. The back wall 52 forms the back of the box shaped outlet head 50 and extends between the smaller base of the trapezoid shaped top wall 73 and bottom wall 56. The back wall 52 is spaced apart from the central axis Z and is substantially parallel to the datum plane YZ at a first side of the datum plane YZ. The outlet opening 72 and the lamellae 80 extend at an opposite second side of the datum plane YZ with respect to the back wall 52 spaced apart from and orientated substantially parallel to the central axis Z. The outlet opening 72 covers most part of the front and sides of the box shaped outlet head 50 covering more than half of the outline of the outlet head 50 when viewed along the central axis Z. The outlet opening 72 and the lamellae 80 intersect or extend through the plane of symmetry XZ at the second side of the datum plane YZ and intersect or extend through the datum plane YZ at both sides of the plane of symmetry XZ. The front of the outlet head 51 is spaced further apart from the central axis Z than the back wall 52. The outlet head 50 is flared from the back wall 52 towards the front of the outlet head 51. The front of the outlet head 50, and therewith the outlet opening 72 and the lamellae 80, therefore is wider than the back wall 52. As best shown in figures 1B and 3, in this example the base 51 has a ring shaped base collar 55 that defines the inlet opening 54. The bottom wall 56 of the base 51 extends away from and substantially transverse to the central axis Z. The bottom wall 56 merges in an outwardly direction away from the central axis Z into a curved circumferential base ridge 57 of the base 51. The top wall 73 of the top cover 70 extends substantially parallel to the bottom wall 56, away from and substantially transverse to the central axis Z. The top wall 73 merges in an outwardly direction away from the central axis Z into a curved circumferential top ridge 74 of the top cover 70. The base ridge 57 and the top ridge 74 respectively merge into a back wall bottom portion 53 and a back wall top portion 71 to form the back wall 52 of the outlet head 50. The back wall bottom portion 53 and the back wall top portion 71 meet and are connected to each other substantially halfway between the bottom wall 56 and the top wall 73. The back wall 52 wraps around or covers a small portion of the sides of the outlet head 50. The base ridge 57, the top ridge 74 and the back wall 52 define the outlet opening 72 that covers a majority of the front and sides of the box shaped outlet head 50.

As best shown in figure 3, the base collar 55 has a U- or V-shaped section, having an undulating leg that is closer to the central axis Z, and a straight leg that is further away from the central axis Z. At the back side of the outlet head 50 the base collar 55 merges into the bottom wall 56 that extends substantially transverse away therefrom. In the direction away from the central axis Z, the bottom wall 56 curves upwards to form the base ridge 57 and the back wall bottom portion 53 of the base 51. At the opposite front side of the outlet head 50 the base collar 55 curves away from the central axis Z to merge into a raised section 59 of the bottom wall 56. In the direction away from the central axis Z, the bottom wall 56 curves upwards to form the base ridge 57 of the base 51. The bottom wall 56, the base collar 55 and the base ridge 57 define a circumferential first receptacle 60 for fluids, and the base collar 55 defines a circumferential second receptacle 61 for fluids between the legs thereof.

The base 51 comprises first drain holes 62 in the bottom wall 56 near the terminal ridge 57 to drain fluids from the first receptacle 60, and second drain holes 63 in the base collar 55 to drain fluids from the second receptacle 61 of the outlet head 50. The base 51, in particular the bottom wall 56 thereof, is convex towards the top cover 70 in the datum plane YZ, having its apex in the plane of symmetry XZ.

The top cover 70, in particular the top wall 73 thereof, is convex away from the base 51 in the datum plane YZ, having its apex in the plane of symmetry XZ.

The convex shape of the base 51 ensures that fluids that are received in the first receptacle 60 flow towards the base ridge 57 and towards the first drain holes 62 to be drained from the outlet head 50. The apex, having its apex in the first plane The base 51 of the outlet head comprises four columns 58 that extend transverse from the bottom wall 56 substantially parallel to the central axis Z towards the top cover 70. the columns 58 are arranged near the corners of the bottom wall 56 in a quadrilateral arrangement when viewed along the central axis Z.

The columns 58 have an oval shaped cross section.

The multiple stacked lamellae 80 of the outlet head 50 extend substantially transverse to the central axis Z in the outlet opening 72. As best shown in figures 1B and 3, the lamellae 80 have, when viewed along the central axis Z, a substantially symmetrical trapezoid shaped outline that corresponds to the shape of the bottom wall 56 of the base 51 and the top wall 73 of the top cover 70. The lamellae 80 determine a circular lamella passage 82 that corresponds to the circular inlet opening 54 of the base 51 of the outlet head 50. Each lamella 80 forms a slat like continuous unit that extends around the central axis Z of the outlet head 50. Fach lamella 80 comprises a circumferential base blade 83 and a circumferential raised portion 84 that forms a continuation of the base blade 83 that faces the central axis Z.

The base blade 83 of each lamella 80 is orientated substantially parallel to the bottom wall 56 of the base 51 and to the top wall 73 of the top cover 70 and to the base blade 83 of the other lamellae 80. The base blade 83 is convex towards the top wall 73 of the top cover 70 parallel to the datum plane YZ of the outlet head 50. The apex of the base blade 83 is located in the plane of symmetry XZ and is towards the top wall 73. The raised portion 84 is raised towards the top wall 73 of the top cover 70 with respect to the base blade 83 along the central axis Z.

The raised portion 84 extends obliquely from the base blade 83 towards the top wall 73 of the top cover 70 and towards the central axis Z.

The raised portion 84 of each lamella 80 is orientated substantially parallel to the raised portion 84 of the other lamellae 80. Each lamella 80 comprises four column collars 85, one near each corner thereof.

The column collars 85 extend substantially parallel to the central axis Z.

The column collars 85 have an oval cross section that corresponds to the cross section of the columns 58 of the base 51, and define column passages 85 through which the columns 58 extend.

The lamellae 80 are stacked on the base 51 by placing them with the respective column collars 85 around the columns 58 of the base 51. The lamellae 80 are spaced apart along the central axis Z by the column collars 85. In this example five lamellae 80 are stacked on the base 51 to define four slits 81. The stacked lamellae 80 therewith form a circumferential grid around and substantially parallel to the central axis 7. The placement part 10 of the ventilation assembly

1 comprises, in this example, a square shaped flashing 11 from a multilayered covering material for roofs, having the properties of lead. The flashing 11 merges into an upwardly protruding flashing collar 12 that defines a circular roof passage 13 around the central axis Z, in the center of the flashing 11. It is to be understood that the placement part is not limited to the flashing 11. Other embodiments that can connect a tube like object to a roof may be used, such as a rigid plate for use on a slate roof.

10 The tubular connector duct 20 of the ventilation assembly 1 comprises a circumferential ring 23 that extends from the outer surface of the connector duct 20 substantially transverse to the central axis Z. The circumferential ring 23 divides the connector duct 20 into an upper first end portion 21 that is configured to be connected to the outlet head 50 and a bottom second end portion 22 that is configured to be connected to the ventilation duct.

At the second end portion 22 the connector duct 20 comprises barb protrusions 24 on its outer surface. The barb protrusions 24 allow the ventilation duct such as a flexible pipe or hose to be moved or slid around the second end portion 22 towards the circumferential ring 23 but hinder or lock the ventilation duct from moving or sliding in the opposite direction. The connector duct 20 comprises an integrated fastener 25 for fastening the ventilation duct to the second end portion 22 of the connector duct 20. The fastener 25 comprises a cable tie 26 and an elongated that holds the cable tie 26 at its distal end. The cable tie holder 27 extends downwards from the circumferential ring 23 parallel to and spaced apart from the outer surface of the second end portion 22. The integrated fastener 25 allows for the ventilation duct to be moved or slid unhindered around the second end portion 22 towards the circumferential ring 23. When the flexible ventilation duct is in place the cable tie 26 can be fastened and tightened around the ventilation duct and the second end portion 22 to fixate the ventilation duct to the second end portion 22 of the connector duct 20 in a direction parallel to the central axis Z. At the first end portion 21 the connector duct 20 comprises circumferential ridges 30 on its outer surface near the edge thereof. The circumferential ridges 30 are interrupted by two V-shaped notches 31 in the edge of the first end portion 21 of the connector duct 20. The base 51 1s configured to be mounted to the connector duct 20 such that, in a mounted state of the ventilation assembly 1, the inlet opening 51 is aligned with the connector duct 20 to receive the gasses to be exhausted. In particular the base 51 is configured to be mounted with the base collar 55 to the first end portion 21 of the comnector duct 20, more in particular to the first end portion 21 of the connector duct 20 in cooperation with the placement part 10. As best shown in figure 3, in the mounted state of the ventilation assembly 1 the first end portion 21 of the connector duct 20 protrudes above the roof, through the roof passage 13 of the placement part 10. The outer surface of the first end portion 21 of the connector duct 20 tightly fits inside or abuts the flashing collar 12 and the circumferential ring 23 of the connector duct is close to or abuts the flashing 11. The ridges 30 of the connector duct 20 protrude beyond the flashing collar 12 of the placement part 10 and tightly fits inside or abuts the inside of the base collar 55 of the base 51 of the outlet head 50. The inside of the base collar 55 at the same time tightly fits around the outside of the flashing collar 12. The placement part 10 is clamped between the base collar 55 of the base 51 and the end portion 21 of the connector duct

20. The locking protrusion 32 of the connector duct 20 sits inside the locking recess 14 of the placement part 10 to fixate the connector duct 20 with respect to the placement part 10 in a rotation direction R around the central axis Z.

The base 51 comprises a notch 64 in the lower edge of the terminal collar 55. The notch 64 forms an upper index of the base 51. The placement part 10 comprises a deformation 14 at the transition area between the flashing 11 and the flashing collar 12. The deformation 14 forms a middle index of the placement part 10. The connector duct 20 comprises a protrusion 32 at the transition area between the circumferential ring 23 and the first end portion 21 of the connector duct 20. The protrusion 32 forms an lower index of the connector duct 20. The upper index, the middle index and the lower index correspond to each other to, in the mounted state, index or fixate the base 51 of the outlet head 50, the placement part 10 and the connector duct 20 with respect to each other, in a rotation direction R around the central axis Z.

Figure 3 shows the ventilation assembly 1 when mounted to the roof 2 that has a sloped main roof surface. The central axis Z of the ventilation assembly 1 extends transverse to the sloping roof 2. The top cover 70 prevents rain from directly entering the outlet head 50 of the ventilation arrangement. The convex shape of the top cover 70 ensures that condensation from the exhausted gasses on the top cover 70 flows to the sides thereof.

The convex shape of the base blade 83 of the lamellae 80 in combination with the rain-impact resistant raised portion 84 reduce or prevent rain blown by wind from entering through the outlet opening 72 into the outlet head

70. The configuration of the lamellae 80 provides little drag or friction to the exhausted gasses, therefore the outlet head 50 causes low pressure losses to a ventilation system.

The convex shape of the base blade 83 in combination with the raised portion 84 further ensures that any condensation flows to the outside of the lamellae 80. The run-off condensation of the lamellae 80 and the top cover 70 is collected in the first receptacle 60 of the base 51 and is drained towards the roof 2 through the first drain holes 62. The sloped orientation of the base 51 aids in the draining of the condensation from the first receptacle 60. Rain or condensation that is nevertheless blown past the lamellae 80 by wind is collected in the second receptacle 61 in the base collar 55 of the base 51 and is drained towards the roof 2 through the second drain holes 63. The back wall 52 of the outlet head 50 is orientated slope upwards and faces the ridge of the roof 2. In this way the back wall 52 covers the outlet head for strong airflows that pass downwards along the roof 2 and prevents rain or water from being blown into the outlet head 50 from that direction. As this airflow direction is often the predominant airflow direction to which the outlet head 50 is exposed, the back wall 52 provides further increased protection against rain blown by wind from entering through the outlet opening 72 into the outlet head

70.

It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention.

Claims

CONCLUSIONS

1. Ventilation assembly for passage of gases through a roof, comprising an exhaust header comprising a base having a bottom wall and an inlet opening for receiving gases to be exhausted, a top cover having a top wall above the bottom wall, and a rear wall extending between the bottom wall and the top wall, the base, the top cover and the rear wall defining an outlet port and a flow chamber between the inlet port and the outlet port for the received gases, the inlet port having a central axis, and the outlet head having an imaginary first face which including the central axis and extending through the back wall, and having an imaginary second face containing the central axis and transverse to the first face, the back wall extending on a first side of the second face and the outlet opening extending to least extending on an opposite second side of the second face, the outlet head comprising a plurality of fins extending into the outlet opening to define a plurality of slits in the outlet opening, and the vanes having a base blade and a raised portion forming a continuation of the base blade facing the central axis, the base blade being convex in the direction of the top cover parallel to the first face or the second face of the outlet head, and the raised portion is raised in the direction of the top cover relative to the base blade.

The ventilation assembly of claim 1, wherein the outlet opening extends through the first face and through the second face on both opposite sides of the first face.

A ventilation assembly according to claim 1 or 2, wherein the bottom wall and/or the top cover merge into the rear wall to form the rear wall.

A ventilation assembly according to any one of the preceding claims, wherein the outlet head has a box shape, the top wall and the bottom wall extend transverse to the central axis and, when viewed along the central axis, have a trapezoidal shape.

A ventilation assembly according to any one of the preceding claims, wherein the louvers extend about the central axis and the inlet opening to form a continuous unit about the central axis, the base blade and the raised portion extending circumferentially about the central axis.

6. Ventilation assembly according to one of the preceding claims, in which the base blade merges into the raised part over an angular line.

7. Ventilation assembly according to claim 6, wherein the angular line extends circumferentially around the central axis.

8. A ventilation assembly according to any one of the preceding claims, wherein the raised portion is conically shaped.

9. A ventilation assembly according to any one of the preceding claims, wherein the slats form separate units that are stacked on top of each other.

A ventilation assembly according to any one of the preceding claims, wherein the base comprises a plurality of columns extending parallel to the central axis in the direction of the top cover, and the louvres comprise a plurality of respective column passages through which the respective columns extend, the columns and the columned aisles in a quadrilateral arrangement when viewed along the central axis.

The ventilation assembly of claim 10, wherein the louvers include column collars defining the column passages and spaced the louvers along the central axis.

12. Ventilation assembly according to one of the preceding claims, in which the slats are identical to each other.

A ventilation assembly according to any one of the preceding claims, wherein the base is convex in the direction of the top cover parallel to the vanes, with the apex thereof in the first plane.

A ventilation assembly according to any one of the preceding claims, wherein the top cover is convex from the base parallel to the vanes, with the apex thereof in the first plane.

A ventilation assembly according to any one of the preceding claims, wherein the base comprises a container around the inlet opening for receiving fluids, and a drain hole for discharging received fluids from the container.

A ventilation assembly according to any one of the preceding claims, comprising a connecting conduit comprising a first end portion which, in an assembled state of the ventilation assembly, projects above the roof, and a second end portion below the roof configured to be mounted to an end portion of a vent conduit, the base of the outlet header being configured to be mounted on the first end portion of the connecting conduit such that, in the mounted state of the vent assembly, the inlet opening is aligned with the connecting conduit.

The ventilation assembly of claim 16, including a locating member configured to connect the ventilation assembly to the roof, the locating member being sandwiched between the base of the inlet header and the first end portion of the connecting conduit in the assembled state of the ventilation assembly.

18. Ventilation assembly according to claim 17, wherein the outlet head, the connecting pipe and the positioning part comprise corresponding indexes to fix the outlet head, the connecting pipe and the positioning part relative to each other in a rotational direction about the central axis in the mounted condition.

19. A ventilation assembly according to any one of claims 16-18, wherein the central axis extends transversely of the main roof surface in the mounted position.

A ventilation assembly according to any one of claims 16-19, wherein, when the main roof surface is sloping, the rear wall is oriented uphill and the outlet opening is oriented at least downhill.

The ventilation assembly of any one of claims 16-20, wherein the connecting conduit at the second end portion comprises an integrated fastener configured to fix the ventilation conduit to the connecting conduit in a direction parallel to the central axis.

The ventilation assembly of claim 21, wherein the attachment means comprises a cable tie. -0-70-0-70-0-0-0-0-