WO2005093333A1

WO2005093333A1 - Ventilation system and intake pipe

Info

Publication number: WO2005093333A1
Application number: PCT/NL2005/000227
Authority: WO
Inventors: Norbert Peter Vroege; Jelle Van Stegeren
Original assignee: Innosource B.V.
Priority date: 2004-03-26
Filing date: 2005-03-25
Publication date: 2005-10-06
Also published as: NL1025831C2

Abstract

Ventilation system consisting of a fan and an intake pipe (6). The intake pipe (6) consists of a relatively rigid frame (13) of plastic material. This frame delimits a cylindrical space which is closed off by means of a plastic film (17). The plastic film (17) is fitted limply on the frame (13), so that sound waves in the intake pipe do not encounter a 'hard' surface and can be diverted to the adjoining wall.

Description

Ventilation system and intake pipe

The present invention relates to a ventilation system according to the precharacterising clause of Claim 1.

Such a ventilation system is generally -known in the state of the art. Such ventilation systems are used, for example, in buildings where the surroundings thereof are subject to high noise pollution, hi such a case it is not possible to ventilate by means of simple windows. Such ventilation systems are also used in buildings with controlled mechanical ventilation, where the incoming and outgoing quantity of air is accurately controlled.

In all cases the aim is to bring air into the building with as little noise as possible. In order to ac-hieve this, in the state of the art ventilation installations are proposed with specially designed fans and housings in which soundproofing material has been installed.

Although it is possible to achieve appreciable damping of the ambient sound by this means, the aim is for further limitation of the noise emanating from the surroundings that enters a building.

One possibility is to cover the intake pipe with soundproofing material. Such an intake pipe extends t-hrough the wall that forms the link between the interior of the building and the surroundings. However, the soundproofing material is porous, as a result of which undesirable bacteria, moulds and other life forms are produced, with or without the ingress of moisture. One example of this is found in JP 2003064797. In this case there is a rigid, closed outer pipe that completely surrounds the sound duct. A soundproofing material, which is held in place by a grating, is arranged inside.

The use of increasingly more soundproofing material leads to the need to make larger holes in outside walls, w-hich is undesirable.

The aim of the present invention is to provide a ventilation system by means of which a further limitation in the sound emanating from the surroundings is possible before it enters a building. Said aim is achieved with a ventilation system having the features of Claim 1.

It has been found that if the intake pipe consists entirely of a "hard" material, sound waves are reflected and transmitted undamped. As indicated above, although covering with a soft sound-absorbent material is a solution for restricting the sound, hygiene problems are associated with this.

According to the present invention it is proposed to construct the intake pipe as a frame with a relatively large opening surface area and to cover these openings with a thin-walled film or foil material. T-his t-hin-walled film or foil material will give with the sound waves.

That is to say the film or foil material does not constitute a hard surface for sound waves.

Appreciable damping of sound will be produced as a result. This damping can be further improved if the film or foil material is fitted limply on the frame. l?n such a case it is even possible that the vibrations are transmitted to the opening in the wall, as a result of which further damping occurs. That is to say, the limply fitted film or foil material constitutes locally both the inner limit and the outer limit of the intake pipe.

Here limp material is understood to be a material that essentially transmits all sound from the interior of the intake pipe to the exterior thereof. This means that essentially no damping of sound by the film or foil material takes place. Moreover, preferably no reflection of the sound by the film or foil material, w-hich is fitted limply on the frame, takes place.

It has been found that appreciable soundproofing is possible by means of the invention, h a comparative test with a ventilation installation with a conventional hard pipe, damping of 47 dBA was obtained with a ventilation installation of optimum construction. Damping of 54 dBA is easily possible with the intake pipe according to the invention.

A pipe with a diameter of 105 mm provided with the limply fitted film or foil material is mentioned here as an example. Better damping can be obtained with such a pipe than with a pipe with an internal diameter of 100 mm and an external diameter of 160 mm, where optimised soundproofing material has been arranged between the interior and exterior of the pipe. This means that it is possible with the present invention to suffice with intake pipes of smaller diameter, as a result of which smaller holes have to be made in building constructions.

The thin-walled film or foil material can comprise any film or foil material -known in the state of the art, such as metallic material. However, t-his preferably consists of plastic. This plastic can comprise a woven fabric that is watertight and has limited permeability to gas. However, the film or foil can also be gastight. The thickness of the film or foil is as small as possible and is preferably below 0.2 mm and more particularly t-his thic-kness is approximately 0.05 mm.

The surface area of the openings at the location of the damping is preferably at least 50 %, and more in particular at least 80 %, of the total surface area. In the case of a wall without a cavity damping will be able to take place over the entire length thereof, whilst in the case of a cavity wall damping is preferably achieved at the location of the cavity.

The invention is particularly effective in damping frequencies between 75 and 10,000 Hz.

If the intake pipe is run through a cavity wall, the relevant openings are preferably made at the location of the cavity. The sound can then be conducted into the cavity. The openings can comprise a few large openings but also a large number of smaller openings.

The frame on which the film or foil material is fitted can be of particularly simple construction. According to one embodiment the frame consists of two spaced terminal rings with spacers extending between them. The foil or film material can be fitted either on the inside or on the outside with respect to the frame. It is also possible, for example using injection moulding, to arrange the film or foil material "in the thickness" of the frame material.

The invention also relates to an intake pipe for a ventilation installation comprising a frame with two spaced circular terminal rings, spacers extending between them and a closing cylindrical film or foil material fitted on said frame, said film or foil material being fitted limply on said frame. The diameter of the pipe is at least approximately 50 mm and in general approximately 100 mm.

The pipe can be produced in one piece. However, it is also possible to produce the pipe from a flat sheet consisting of a relatively thick part with windows and thinner film or foil material arranged thereon (to be arranged thereon). On site or at another location such a flat sheet can be folded to produce a pipe and the ends fixed to one another in some way or other. It is also possible to fit the film or foil material separately with respect to the frame.n such an embodiment the film or foil material is preferably fitted around the frame on the outside. In this context it is possible first to arrange the film or foil material in the opening in the wall, followed by the frame.

If the film or foil is fixed to the frame, gluing, heat sealing and the like can be used for this, where in addition reference is made to the injection moulding technique described above.

The ventilation system according to the present invention will be explained in more detail below with reference to an illustrative embodiment shown in the drawing. In the drawing:

Fig. 1 shows, diagrammatically in cross-section, the ventilation system fitted in a building according to the invention;

Fig. 2 shows, in perspective, the intake pipe according to the present invention.

In Fig. 1 the ventilation system according to the invention is indicated in its entirety by 1. This consists of a ventilation installation 8 that is fitted against the inner wall 3 of a cavity wall 2. The outer wall is indicated by 4. The ventilation installation comprises a fan 11 fitted in a housing. This housing is provided with soundproofing material 12. The housing is provided with an inlet opening 9 and an outlet opening 10. Inlet opening 9 adjoins an intake pipe 6. This intake pipe 6 is fitted in an opening 7, which extends through both the inner wall 3 and the outer wall 4. At the free end the intake pipe 6 is provided with a terminal grating 5.

Details of the intake pipe 6 can be seen in Fig. 2. This pipe comprises a frame 13 consisting of terminal rings 14 and 15 and spacers 16 arranged between them. The frame can consist of any material -known in the state of the art, such as a metallic material or plastic. The frame is relatively rigid, so that a small size of the terminal rings 14, 15 and stays 16 can suffice. As a result large openings are produced and these are covered by plastic film 17. Plastic film 17 is fitted limply on the frame 13 and is airtight. As a result it is not possible for gases to pass from the cavity between the walls 3 and 4 into the intake pipe 6.

As a result of the "soft" nature of the intake pipe 6, sound emanating from the surroundings will be transmitted to the cavity via the openings in the frame 13 exclusively through the limp plastic film material, virtually without damping or reflection. Damping of more than 7 dBA has been observed. The film material used is preferably plastic film and PNC material is mentioned as an example.

Although the invention has been described above with reference to a preferred embodiment, it will be immediately understood by those skilled in the art that numerous variants are possible that fall within the scope of the appended claims.

Claims

1. Nentilation system (1) comprising a ventilation installation (8) with a housing provided with an inlet opening (9) and an outlet opening (10), which housing has soundproofing material (12), as well as an intake pipe (6) that can be connected to said inlet opening and can be linked to the surroundings, said intake pipe comprising a tubular supporting frame (13) covered with a thin- walled film or foil material (17), characterised in that film or foil material is fitted limply on said frame and locally forms the inner limit and outer limit of said intake pipe.

2. Nentilation system according to claim 1 wherein said film or foil material comprises a plastic film.

3. Nentilation system according to one of the preceding claims wherein said frame comprises two spcaed terminal rings (14, 15) with a spacer (16) extending between them.

4. Nentilation system according to one of the preceding claims wherein said intake pipe is cylindrical.

Intake pipe (6) for a ventilation installation (8) comprising a frame (13) with two spaced circular terminal rings (14, 15), spacers (16) extending between them and a closing cylindrical film or foil material (17) fitted on said frame, wherein said film or foil material is fitted limply on said frame.

Nentilation system according to Claim 5, wherein the diameter of said pipe is at least 50 mm.

7. Nentilation system according to Claim 5 or 6, wherein the thickness of said film or foil is less than 0.2 mm.