A dome shaped element for a pipe duct of a tile profiled metal sheet roofing

The present invention concerns a dome shaped or dome-like element tapering upwards for a pipe duct of a tile profiled metal sheet roofing of a building, said element having in its upper part an opening for receiving the pipe to be led through the roof, and having in its lower edge a flange part with mounting holes, said flange part including an arched portion for the wave crest of the tile profiled metal sheet roofing at the front and back end of said element.

A Finnish patent publication discloses a solution for a pipe duct having a dome-like element with a straight, stiff flange part, which when being mounted on a corrugated sheet roof is attached with screws to the wave crests of the corrugation, whereby the flange does not set itself sealed against the roof sheet but an open gap is left between the crests of the corrugation. For providing sealing between the corrugated roofing material and the pipe led through the roof, the pipe is equipped with a bellows portion connecting the pipe part below the roof and the pipe part above the roof, having in its housing a flexible flan- ge part to be attached to the roofing material with screws. For providing an adequate sealing, a formable aluminium ring was placed onto the flange, said ring have to be formed complementary with the profile of the roofing material prior to the attachment with screws.

Registered Finnish utility model no 2123 discloses an element of the type mentioned in the preamble. This element known in the art is totally made of hard plastic, whereby it is suitable only to one type of tile profiled metal sheet roofing. Thus, a different shaped dome-like element must be manufactured for each different type of tile profiled metal sheet roofing. The flange part of this element known in the art is provided with a groove opening downwards, where a separate gasket must be placed for providing an adequate sealing between the dome-like element and the roofing material.

The object of the present invention is to provide such a dome-like element for tile profiled metal sheet roofing that is easily and simply mountable onto different profiles of tile profiled metal sheet roofing. This is provided by a dome-like element characterized in that the element is mainly made of hard plastic, but on the bottom side of the flange part

and inside the dome-like part, up to the level of the highest points of the arched portions of the flange part, there is provided a layer of soft, rubber-like plastic being thinner inside the dome-like part than in the flange part, and that on the area between the flange part and the dome-like part there are formed bellows portions extending between said arched por- tions of the flange part and having walls totally or for the main part made of soft rubber- like plastic, whereby the flange part, when the element is being attached, is arranged to adapt for the form of corrugated tile profiled metal sheet roofings of different forms and heights, whereby only the upper parts of the arched portions of the flange part are form- stable and rigidly connected to the dome-like part of the element.

Heights of the tile profiled metal sheet roofings range from 15 mm up to 45 mm, and the crests of the roofings can have symmetrical profiles or wave-formed to one or the other direction. At the crest of the corrugation, the most of the commercially available tile profiled metal-sheet roofings, however, have about the same profile form, so that these crests set very well to the form-stable, arched portions in the flange part of the element according to the invention.

For making the dome-like element according to the invention to fit as good as possible and to as many commercially available tile profiled metal sheet roofings as possible, the height of the arched portions formed to the flange part of the element corresponds to the average height of the highest and lowest corrugations or crests of the tile profiled metal sheet roofings available in the market. The flange part of the dome-like element is flexible as much upwards as downwards, when the element is placed on the lowest, respectively highest tile profiled metal sheet roofing.

On the outer surface of the bellows portion, on top of the material of flexible rubber-like plastic, there is preferably a film of hard plastic having a thickness of 0,2 mm. Thereby the whole outer surface of the dome-like element is of hard plastic, and has also the same colour. No boundary can be seen between the bellows portions and the other parts of the element. Because the thermoplastic elastomer used as soft, rubber-like plastic, has a lower UV-resistance than the polypropylene used as hard plastic, the use of the above mentioned film also provides a better UV-resistance for the element.

On the hard plastic layer of the upper surface of the flange part of the dome-like element there is formed an annular swell surrounding the dome-like part outside the bellows parts and expanding at each mounting hole into a branch surrounding the respective mounting hole. Due to this swell, a desired tightening effect is provided, when the element is attached to the tile profiled metal sheet roofing. For enhancing the sealing effect, parallel fins are formed to the soft rubber-like layer on the lower surface of the flange part, surrounding the dome-like part.

The invention will be described in more detail in the following, with reference to the enclosed drawing, wherein:

Figure 1 shows a perspective view of the dome-like element according to the invention,

Figure 2 is a front view of the element,

Figure 3 is a side view of the element,

Figure 4 shows the element directly from above,

Figure 5 shows the element directly from below,

Figure 6 is a view corresponding to Fig. 2, showing schematically three different forms of tile profiled metal sheet roofings, on which the element according to the present invention can be mounted.

Figure 7 shows a schematic section through the walls of the dome-like element along line A-A in Figure 3, and

Figure 8 shows a section along line B-B in Figure 2.

The element according to the invention is mainly produced of hard plastic, preferably of polypropylene, but at the lower part of the element partly also of soft rubber-like plastic, preferably of thermoplastic elastomer, said plastics being injected to one and the same mold with two different injection units, so as to interconnect the different plastic mate- rials with each other. The element includes a dome-like part 1, which is made of hard

plastic, and surrounding the lower edge thereof, a flange part 2 to be attached to the tile profiled metal sheet roofing, having a layer of soft, rubber-like plastic on its bottom side. At the front and back end of the element the flange part 2 has an arched portion 5, 6 for the crest of the tile profiled metal sheet roofing, the upper parts of the arched portions being form-stable and rigidly connected to the dome-like part 1 of the element. The soft, rubber-like plastic layer extends thinner onto the inner surface of the dome-like part 1 up to the level of the highest point of the arched portions 5 and 6, as shown by dark areas in Figures 7 and 8. The dome-like part 1 has an opening 3 for receiving a pipe to be mounted on an inclined roof, in a vertical position, in other words diagonally with respect to the inclined level of the flange.

For achieving flexibility as good as possible, there are bellows parts 8 formed on the area between the dome-like part 1 of the element and the flange part 2, said bellows parts extending between said rigid arched portions 5, 6 of the flange part 2. The walls of the bellows parts 8 are either totally or mainly of soft rubber-like plastic. The outer surface of the bellows part 8 is advantageously covered with a film of hard plastic having a thickness of 0,2 mm, on top of the flexible rubber-like plastic material. For this reason the total outer surface of the element has the same colour and is tidy. If the film of hard plastic is not used in the flexible portions, the injection of the rubber-like plastic is much more demanding, because the soft rubber-like plastic in that case easily spreads also in places where it is not meant to. Because the UV-resistance of the rubber-like plastic to be used is worse than the UV-resistance of the polypropylene used as hard plastic, said film also forms a UV-protection for the bellows parts 8.

Due to the flexibility of the lower part of the element, the flange part 2 easily adapts for the form of corrugated tile profiled metal sheet roofings having different forms and heights. The soft rubber-like plastic layer forming the lower surface of the flange part 2 improves the tight contact of the flange part 2 with the surface of the metal-sheet roofing, when the element is fixed.

At the end of the element, that when mounted faces to the ridge of the roof, there is a recess 4 between the dome-like part 1 and the flange part 2, for providing more extension

to the lower end of the dome-like part 1 in the vertical direction. When the element is mounted in place, this recess 4 comes inside the opening cut to the metal-sheet roofing.

The flange part 2 has mounting holes 7 for screws for fixing the element to the metal sheet roofing. At the ends of the element, in other words on the area of the arched portions 6, 7of the flange part 2, the mounting holes 7 are closer to another than at the places where the flange part 2 is in contact with the lower points of the metal sheet roofing profile, as in more detail shown in Figures 4 and 5. This is to secure a tight attachment, which is still improved, if there are parallel fins 9 formed onto the lower surface of the flange part 2 surrounding the dome-like part 1.

The height of the arched portions 5, 6 is preferably chosen to correspond to the average height of the waves or crests of the tile profiled metal sheet roofings available on the market, whereby the suitability of the element for different types of tile profiled metal sheet roofings can be optimized. Thereby the skirts of the flange part 2 must be in its basic position flexible as much upwards as downwards, when the element is mounted onto the metal sheet roofing with lowest, respectively highest profile.

In the hard plastic layer on the upper surface of the flange part 2 there is formed an annular swell 10 surrounding the dome-like part 1 outside the bellows parts 8, expanding at each mounting hole 7 into a branch 10a surrounding the respective mounting hole 7. By means of this swell 10, the sealing properties of the flange part 2 are still improved.

Figure 6 shows schematically three tile profiled metal sheet roofings with different profile shapes, onto which the dome-like element according to the invention can be mounted tightly. There are shown two tile profiled metal sheet roofings A and B with low profiles providing that the skirt of the flange part 2 must be more or less lifted upwards when mounting the element, and one tile profiled metal sheet roofing C with a high profile providing that the skirts of the flange part 2 are lowered downwards when mounting the element.

When the pipe installation has been led through the roof, the dome-like element is attached with screws to the metal sheet roofing. The opening 3 in the upper end of the

dome-like part forms a suitable angle with the bottom level of the element. The opening is dimensioned so that it is suitable for use with roofs having different inclinations. Finally still another dome-like element is mounted onto the element according to the present invention, the opening thereof being sealed against the outer surface of the pipe.