GB2141756A - Sound deadening means - Google Patents

Abstract

This is a closed flexible bag tightly filled with heavy particulate material, e.g. as crushed cinders or spent shale. There are means to hang or otherwise locate each such bag, e.g. as part of a portable or permanent screen or wall. The bag surface may be quilted or head reflective, and may be treated to resist attack by rodents or vermin. <IMAGE>

Description

SPECIFICATION Sound deadening The invention relates to sound deadening means and methods, and particularly applicable to the deadening of sound transmitted through buildings.

It is well known to insulate buildings, and building fitments such as hot water tanks, to reduce the rate at which heat escapes from inside the building. Such insulators are conventionally of lightweight material.

For example, it is well known to unroll fibreglass blankets between the roof joists, or to fill the space between the joists with fibreglass granules, to reduce heat loss through the roof of a house.

It is equally well known to lag the hot water cylinder in a house with a blanket in the form of a flexible plastics quilt which is filled with fibreglass and strapped round the tank.

Expanded polystyrene sheeting is another well known material which is used to insulate house walls internally against excessive heat loss.

Cavity wall insulation also makes use of polystyrene foams which are pumped into the wall cavity to expand and set therein.

Heat insulating blocks, for example those available to the building trade under the name DUROX, can be used to construct the inner walls of a cavity walled house, once again in orderto reduce heat loss from the inside to the outside of the house.

The invention takes as its starting point this known and widespread use of lightweight materials for heat insulating purposes. It is founded on the realisation that relatively little has been done to reduce noise transmitted within the houses. Carpets, curtains and furniture will absorb and deaden noise to a certain extent, but these are essentially secondary noise deadening means.

The lightweight heat insulating means reviewed above will also have a certain noise deadening effect, but again this is minimal and is certainly not an intended attribute of such products.

Double-glazed window units are primarily intended as heat retaining means. They can have a certain noise deadening effect, but the gap between the two panes of the unit would have to be many times greater than it conventionally is in order for any appreciable sound deadening effect to be observed. Such units in any event do not deaden noise transmitted within the building itself.

In summary, little attention has been paid to the deadening of noise ordinarily transmitted within domestic and other buildings. The heat insulating means, the carpets, the curtaining and other coverings which go into modern houses and buildings are essentially light in weight. Modern furniture, although heavier and therefore more useful for noise deadening than these coverings, again tends to be lighter in weight than its predecessors in previous ages, and also more sparcely distributed about the building.

According to the invention, sound deadening is achieved by disposing about the building a number of bags each tightly filled with heavy particulate material such as crushed cinders or spent shale; the bags are flexible and are suitably shaped to conform to their intended working environment; and the bags are peripherally Icosed so as normally to deny access to the particulate material within the bag.

The use of such heavy materials is in complete contrast to the conventional use of lightweight materials for heat insulating purposes. It contrasts equally with the use of similarly lightweight materials for sound deadening in saloon cars and similar vehicles. Great strides have been made in the sound deadening effectiveness of such materials in the automobile industry in recent years, but, inevitably, these materials are relatively sophisticated and hence expensive. They can also be attacked by rodents and vermin. They therefore form no satisfactory basis for widespread use in traditional building which is the field to which the present invention is primarily directed.

The use of flexible material for the bags gives to the filled bag a limited flexibility despite the tight filling. This limited flexibility enables the bag to conform to some extent to different environments, and increases its versatility over a rigid sheet of sound deadening material.

The tight filling itself enables the bags to be hung or stacked vertically without the filling settling to any appreciable extent, and so the sound deadening qualities of the filled bag remains substantially constant over its entire area when so hung or stacked.

Because the bag is closed peripherally after having been tightly filled, and does not incorporate any re-closable opening, the manufacturing costs of the filled bag kept to a minimum. This is important if the bag is to achieve widespread use in the traditional building industry. It also cuts down to an acceptable minimum the risk of the contents escaping from the bag. There is always the risk of the bag being punctured, but that is inevitable and can be considered an acceptable risk. The risk of the contents escaping through a re-closable opening is unacceptable and is eliminated by the peripherally sealed construction of the bag.

Advantageously the bags may be provided with means to hang or otherwise locate them within a confined environment. Such means may, for example, comprise eyelets in the bag periphery. The bags could then hang vertically, as from a frame work to form a screen reducing the transmission of noise from one side of the screen to the other.

Such a screen is particularly advantageous when used to form part of a controlled environment module for use in large factories, where small numbers of people working on a line system orthe like are required to be properly heated and well lit. A portable version of such a module can be assembled using filled bags embodying the invention, and can then be heated and lit without the rest of the factory having to be heated and lit to the same standard. The cost advantages are clear.

To increase the advantages given by use of the invention, the outer surface of the bag may be wholly or partly reflective of heat. It may, for example, be silvered, as by incorporating a metallic foil surface, whilst of course still being flexible enough to conform to some extent to the intended working environment.

The bag surface may be quilted, for example with a diamond pattern and with each individual diamond then being tightly filled with the heavy particulate material and peripherally sealed to form overall a heavy quilted sheet of sound deadening material.

Alternatively such a quilted material-filled sheet could form the front surface or back surface (or both) of a bag filled between its surfaces with further such material; and then peripherally sealed.

Because bags embodying the invention are heavy, in relation to conventional heat insulating screening orsheeting, they give a certain stability to any structure they are incorporated into. This can have very substantial advantages. For example, the controlled environment module previously referred to can be an inherently stable structure not easily disturbed from its temporary resting place, and yet readily portable once it has been dismantled into its individual sound deadening bags and the frames which supportthem.

The embodiments of the invention are shown in the accompanying drawings. They are only examples of forms which the invention might take within its broadest aspect, but they are currently the best ways known to the applicant of putting the invention into practice.

In Figure 1, bags of heavy duty polythene are tightly filled with relatively heavy particulate sound deadening material such as crushed cinders, spent shale, coal mine waste, broken concrete or other suitable material. Initially each empty bag is peripherally sealed around three out of its four sides.

It is filled with the particulate material through its open fourth side, which is itself then sealed to complete a full peripheral seal which normally denies access to the contents of the bag.

Each bag is thus pillow-shaped, and, like a conventional pillow, can flex to a limited extent.

An eyelet is provided at each corner of the bag, to allow the bag to be hung from hooks on a tubular steel framework which is free-standing and from whose top rail each bag hangsvertically.Asucces- sion of such bags is hung as illustrated in Figure 1 to provide, with the framework, a portable sound deadening screen.

In Figure 2, a similarly tightly filled bag is sausageshaped and sits on metal brackets between the joists of a house roof, to deaden the transmission of noise through the joists. The bag material could again be heavy duty polythene, or it could be a material which had been specially treated on its outer surface to be proof against rodent or vermin attack.

In Figure 3 a series of bags similar to Figure 2 is joined, by suitably sealing a single bag which is then filled and sealed peripherally. This could hang from a framework such as that illustrated in Figure 1, and a number of these bags and frameworks could be built up into a controlled environment module having a roof as well as side walls.

In Figure 4the bag is quilted. The quilting is diamond pattern. Each diamond is initially open along one of its four sides, and is filled through that open side. When tightly filled, it is sealed. Once all the diamonds have been filled in this way, a sheet of filled diamonds is formed and this can be used, as previously outlined, to constitute part of a screen or controlled environment module.

Bags embodying the invention could be incorporated into the stud-work walls of a building. These are internal walls which have no essential load bearing function and which lend themselves ideally to a sound deadening function if they are modified in this way.

In certain environments, sound deadening bags embodying the invention will inevitably contribute greatly to reducing the heat loss from a building or other working environment. This is another advantage given by the invention.

As well as sitting between the joists of a house roof as in Figure 2, the filled bags could be laid between floor joists with similar advantages.

Figure 5 is a section through a bag embodying the invention, the bag having been manufactured in a different way from those illustrated in Figures 1 to 4.

An initially flat sheet of bag material, for example heavy duty polythene, strong reinforced tarred paper, metallised foil or similar, is laid in a mould. The spent shale or other sound deadening filling material is laid on top of it to a depth of, for example, three centimetres. A second sheet of bag material is laid over the uniformly deep layer of filling material, and the two sheets are then fused together around their common periphery and, in this particular case, along lines which create a squared or diamond or other quilted pattern in forming the resulting bag.

In effect, the bag so formed is a uniformly thick sheet of filled material which can flex to a limited extent about the heat-sealed quilt pattern lines running across its surface. It is tightly packed and uniformly thick across its entire area rather than being pillow shaped as previously described.

Figure 6gives some idea of its overall shape.

Figure 7also gives an approximate idea of the controlled environment module previously referred to. In this particular example the module has opposite side walls joined by an end wall and supporting a sloping roof, with access along the whole of one open fourth side of the module.

The walls and roof are made by assembling a scaffolding framework and fastening individual filled sound deadening sheets to it in a manner not unlike that of Figure 1, although the sheets would of course be much more closely packed together to minimise the entry of noise into the module. Other shapes are possible for these modules, as they may be totally closed on all sides with re-closable access openings.

They could be heated and lit appropriately inside.

Bags embodying the invention could be waterproof and could be aesthetically more pleasing if they were to be used either as temporary internal screening or as more permanent outdoor or internal screens. They could, for example, be custom made for inclusion in furniture, to improve the sound deadening qualities of the furniture without necessarily being visible themselves. A sheet similar to that of Figure 6 could, for instance, form an internal lining to the back andlor the side panels of a wing arm chair. Another possibility is to have the bag hung to form a permanent outdoor screen with climbing plants growing over it.

Claims (8)

1. Sound deadening means comprising a flexible bag tightly filled with heavy particulate material and peripherally closed so as normally to deny access to the material within the bag.

2. Sound deadening means according to Claim 1 and provided with means to hang or otherwise locate the bag in its intended working environment.

3. Sound deadening means according to Claim 2 and in which the locating means comprise eyelets.

4. Sound deadening means according to any of the preceding claims and characterised by a quilted pattern in the bag.

5. Sound deadening means according to Claim 4 and in which the quilting is formed in the front or the back or both such surfaces of the bag, and also in which the individual areas in the quilting pattern are themselves filled with the heavy paritculate material.

6. Sound deadening means according to any of the preceding claims and exhibiting a heat reflective outer surface.

7. Sound deadening means according to any of the preceding claims and with a number of the bags located on a framework to form a screen or to form part of a permanent wall of building.

8. Sound deadening means substantially as described herein with reference to and as illustrated in any ppropriate combination of the accompanying drawings.