AU1459797A - A device at a building for preventing propagation of fire and/or fire gases and a method and a device for supply of fluid - Google Patents

Abstract

In a device for preventing propagation of fire and/or fire gases in a building with at least two exhaust aire means (6) and an arrangement (11) generating a negative pressure and connected thereto through a conduit arrangement (8) are on one hand separate first conduits (9) communicating with the exhaust air means and on the other a second conduit (8) communicating with an arrangement (11) generating a negative pressure connected to a volume (12) being a part of the conduit arrangement (8), said volume (12) being formed by means of a container (14), which is arranged to form a liquid trap separating the first conduits (9) from each other when it is filled by liquid.

Description

A DEVICE AT A BUILDING FOR PREVENTING PROPA¬ GATION OF FIRE AND/OR FIRE GASES AND A METHOD AND A DEVICE FOR SUPPLY OF FLUID

FIELD OF THE INVENTION AND PRIOR ART

This invention relates to a device at a building for preventing propagation of fire and/or fire gases according the preamble of claim 1. The invention also relates to a method and a device for fluid supply to a drain water conduit in a building according to the preambles of claims 7 and 13, respectively.

In a building comprising at least two exhaust air means and an arrangement generating a negative pressure connected thereto through a conduit arrangement there is a problem, since fire and fire gases may propagate through exhaust air means and the conduit arrangement. In larger buildings these are normally divided into fire cells, and there is an attempt to separate them fire safely and gas tightly from each other. However, the conduit arrangement constitutes a problem in so far as it extends through walls and floors separating fire cells and thereby causes a risk of propagation.

The problem just mentioned with respect to exhaust air conduits also exists for drain water conduits. These extend vertically through buildings and will thereby constitute break-throughs of possible fire cell divisions. The propagation of fire may easily take place by heating the drain water conduits at a fire so far that they are either destroyed or, especially in the case of metal conduits, function as a heat conductor in such a degree that ig- nition may take place in fire cells adjacent to the fire cell in which a fire exists. A propagation of fire gases may also take place through the drain water conduit.

An additional problem of the technique of today is the difficulty to provide water for fire fighting in a rational way at suitable lo¬ cations in a building. The ordinary water conducting network in a building may for sure provide a certain water volume, but this will be comparatively restricted, since the water supply conduits in the building have mostly a comparatively small cross section area and thereby flow capacity. Thus, it would be desirable to create conditions for considerably more powerful water supply.

A further problem identified within the prior art is that fire gases generated in a fire may procure a fast suffocating of persons present in the building.

SUMMARY OF THE INVENTION

The object of the invention according to claim 1 is to provide a device, in which the risk of propagation of fire and/or fire gases through the conduit arrangement is considerably reduced.

This object is according to the invention obtained by the characteristics defined in the characterizing part of claim 1.

Thus, it is thereby obtained that the first conduits are separated from each other through filling liquid into the liquid trap. Thus, this will prevent propagation of fire and/or fire gases between different first conduits. When on the other hand the container is not filled with liquid the first conduits communicates with the volume defined in the container, so that a negative pressure applied through the second conduit gives rise to an evacuating air flow through the exhaust air means, the first conduits, the container volume, the second conduit and the arrangement generating a negative pressure. According to a particularly preferred embodiment the exhaust air means are units receiving drain water, while the first con¬ duits are also arranged to transport drain water. Accordingly, an embodiment in which one and the same conduit system func¬ tions both as drain water system and as exhaust air system is obtained. By evacuating the exhaust air through the units receiving drain water, i.e. floor drains etc., a satisfying drying effect is obtained through the exhaust air exactly where it is particularly valuable, namely in the "wettest" place in the building, namely where drain water has to leave. This is advan¬ tageous through a reduced risk of moisture damages in the building and by obtaining a better environment for the people living there, not at least since the dry environment in the units receiving drain water and the drain water conduits means bad living and growing conditions for bacteria, fungus, certain noxious insects etc.

With respect to the method and the device according to claims 7 and the 13, respectively, the invention aims at showing ways to improve the possibilities for avoiding propagation of fire and fire gases and/or creating conditions for a more efficient fire fighting in a building provided with a drain water conduit.

The method and the device according to the invention fulfils this object by the characteristics according to the characterizing part of claims 7 and 13, respectively.

The introduction of the fluid in the drain water conduit may then have the following task:

1 ) By filling the drain water conduit with a liquid fluid, preferably water, a good security is obtained against the propagation of a fire or fire gases in the building in the drain water conduit. The liquid stops efficiently fire gases and cools the drain water conduit down.

2) By supplying a fire fighting fluid, for instance water, to the drain water conduit under a high pressure, it is obtained that the very drain water conduit may be utilized as a distribution conduit for the purpose of fire fighting.

3) By supplying a gaseous fluid, especially air, to the drain water conduit the gas/air may be transported to that room of the building, in which the unit receiving drain water is located so that the gas/air may flow into this room through this unit. It is then obtained that the gas/air may be utilized by a person present in the room for respiration purposes. The gas/air may be supplied in such a degree that it pushes flue gases away from the room in question. Liquid/water may simultaneously therewith be supplied to said room for cooling/fire fighting should the conditions require this.

The characteristics mentioned above and additional ones of the invention as well as advantages connected thereto are dis¬ closed more in detail in the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a specific description of embodiments of the invention cited as examples. In the drawings:

Fig 1 is a schematic view illustrating a conduit arrangement installed in a building,

Fig 2 is a partially sectioned side elevation view of the unit re¬ ceiving drain water designed as a floor drain, ig 3 is an exploded view corresponding to the view seen in Fig 2 with the floor drain illustrated there as well as the fluid outlet means connectable to the floor drain,

ig 4 is a schematic view similar to Fig 1 but illustrating an al¬ ternative embodiment,

Fig 5 is a detailed view of a non-return valve also illustrated in Fig 4, in which means for connection of the unit receiving drain water is also illustrated in this Figure, especially a wash basin, to a portion of the drain water conduit accommodating a non-return valve, and the non-return valve is shown in an opened position,

Fig 6 is a view of the non-return valve in closed position in the portion of the drain water conduit belonging thereto, and a connecting element connectable to the portion of the drain water conduit accommodating the non-return valve,

Fig 7 is a view illustrating the connecting element and the portion of the drain water conduit accommodating the non-return valve assembled, and

Fig 8 is a view illustrating the portion of the drain water conduit accommodating the non-return valve and an al¬ ternative means for connecting the unit receiving drain water, which means does not comprise an additional non-return valve.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

The device illustrated in Fig 1 is in the example meant to be adapted to a building having a number of floors 1-5. These are suitably separated fire cells by having in a conventional way walls, ceilings, floors etc., separated from each other. A number of units 6, 7 receiving drain water are arranged in the building. The units 6 are in the example illustrated as being floor drains, while the units 7 are indicated as wash basins.

The building comprises a conduit arrangement designed as a drain water system containing first conduits 9 connected to the floor drains 6 and generally indicated by 8.

The wash basins 7 are in the example intended to deliver the drain water thereof to the floor drain 6 through a conduit 10.

The floor drains 6 are in the example arranged to also function as exhaust air means by a connection of an arrangement 11 generating negative pressure through the conduit arrangement 8 to the floor drains/exhaust air means 6.

To a volume 12 included in the conduit arrangement 8 are on one hand conduits 9 communicating with the floor drain 6 and on the other the second conduit 13 communicating with the arrangement 11 generating a negative pressure connected.

It is emphasized that a minimum criteria for at least one of the aspects according to the present application is that at least two of the floor drains/units 6 have to have separate conduits 9 running to and emerging into the volume 12. In the embodiment of the inventional idea most consequently carried out according to what is illustrated in Fig 1 , all the units/floor drains 6 have separate conduits 9 running therefrom through the volume 12.

The volume 12 is formed by a container 14, which is in a state, in which it is filled with liquid, especially water, corresponding to the level indicated by 15 arranged to form a liquid trap in the container, which separates the conduits 9 from each other with respect to air flow. Furthermore, the liquid trap separates each of the conduits 9 from the second conduit 13.

The conduits 9 extend in the example into the volume 12 so that the orifices 16 of the conduits will be located under said level 15, so that the ends of the conduits 9 will thereby be cut off with respect to air flow from each other by the liquid present in the volume 12, which in the following will be regarded as water.

The container 14 communicates with a receiver 17 of drain water. Although this receiver 17 in a more simple embodiment could consist of a pipe conducting drain water directly away from the building, the receiver has in the example the character of a tank, which receives drain water from the volume 12 through a conduit 18.

Drain water coming from the floor drains 6 are in the normal function intended to flow to the volume 12 through the conduits 9 and directly further to the receiver 17, so that the container 14 is emptied of water or that in in any case no water trap effect is there, i.e. a possible water level in the container 14 is located below the orifices of the conduits 9 in the container 14 and also below the orifice of the conduit 13 in the container. This means that the arrangement 11 generating the negative pressure may generate a negative pressure in the conduit 13, the volume 12, the conduits 9 and the floor drains 6, so that an evacuating air flow from the building is established.

A valve 19 is arranged in the conduit 18 between the container 14 and the receiver 17 and this valve is connected to control means 20, which is arranged to normally keep the valve open, but close it upon a risk of propagation of fire, fire gases or another exceptional event, such as an electric power failure. The device comprises an arrangement 21 for supplying water to the container 14 upon a risk of propagation of fire or fire gases or another exceptional event, such as power failure. This arrangement comprises in the example a water tank 22, a connection 23 arranged between the water tank and the con¬ tainer 14 and a valve 24 arranged therein. This is connected to control means 25, which are arranged to open the valve 24 upon a risk of propagation of fire, fire gases or another excep¬ tional event, such as an electric power failure. The valves 19, 24 and the control means 20, 25 thereof are so coordinated that the valve 24 may not be opened until the valve 19 is closed.

A conduit 26 for refilling of water is connected to the tank 22. This conduit 26 is connected to the water network of the building and contains a valve 27 for controlling the refilling of the tank 22. The valve 27 is suitably controlled by a filling regulator 28, which closes the valve 27 when the tank 22 has been filled to a required extent. The regulator 28 may be arranged to successively fill the tank 22 should the water level therein sink through evaporation or leakage.

The water volume in the tank 22 is at least so great that it manages to fill the volume 12 to a level over the orifices of the conduits 9 in the volume.

It would for sure be possible to fill the container 14 by means of a conduit connected to the water supply network of the building and control the filling by means of a valve arranged therein, but this would lead to a risk that the container 14 could not be filled in the case of a disappearing pressure of the water supplying network. Storage of the water volume in the tank 22 required for filling the container 14 will then lead to a substantially in¬ creased safety of the function. When in a fire situation or the like the tank 22 is controlled to fill the container 14 drain water will then be able to arrive to the container 14 through the conduits 9. The container 14 has a spillway overflow 29 so as to enable drainage of undesired volumes. However, under normal operation this spillway over¬ flow 29 should not allow air to enter in the container 14, since this means a useless leakage. The spillway overflow 29 should therefor be provided with a non-return valve closing against air flow into the container 14 or alternatively a water trap closing against air flow.

The control means 20, 25 may as already indicated be con¬ trolled by suitable detectors, such as temperature, smoke and/or flame detectors. The control means may as an alterna- tive or a complement thereto also be adapted to operate the re¬ spective valves as soon as a driving motor of the arrangement 11 generating a negative pressure stops functioning, for exam¬ ple by an interruption of the current feed thereto. The air evacuation through the conduits 9 is then namely interrupted and for avoiding the risk for propagation of fire gases in a fire situation or propagation of undesired smells when no fire risk exists the valve 19 is upon a power failure controlled to close and followed thereupon the valve 24 to open, so that the container 14 is filled and cuts off against air flow through the conduits 9.

It appears from Fig 1 that a cut-off valve 30 is arranged in each of the conduits 9. Each of the conduits 9 is upstream of the cut¬ off valve 30 connected to means 31 for fluid supply to the drain water conduit 9 in question. These means 31 comprise intake conduits 32. Connection means 33 are connected in parallel with these intake conduits, and a set of connection means 33a may suitably be arranged inside the building, suitably in the at¬ tendance room thereof, normally the basement floor, while the other set 33b is arranged outside the building so as to be available to the fire fighting staff also under severe conditions. These connection means are connected to valves 34 and are in¬ tended to be connected to conduits or the like for supply of fluid to the interior of the building through the conduits 32 and the conduits 9. Thanks to the fact that for each of the drain water conduits 9 there are a separate intake conduit 32, a separate valve 34 and a separate connection means 33, an optional fluid of an optional amount/under an optional pressure may selec¬ tively be applied to each of the drain water conduits 9 and a unit 6 connected thereto.

The fluid in question can for example be water for fire fighting and cooling. According to an alternative it may be so proceeded that the conduits 9 are selectively filled with water to the level or close to the level for the respective unit 6 but not so far that water flows out in the building, by which the drain water con¬ duits 9 will be filled with water preventing fire propagation therethrough. In order to facilitate an appropriate filling of the respective drain water conduit 9 pressure meters are suitably used so as to determine the water column prevailing and adjust the height thereof to the required value. Accordingly, such values should be available to the staff and the conduits 9 or 32 in question should be provided with pressure meters.

A receiver 17 is designed as a tank for providing liquid/water for fire fighting or other purposes, as already mentioned, and it has suitably a spillway overflow 35 placed so that the tank is always substantially filled. Drain water may through this spillway overflow 35 be diverted for taking care thereof in an arbitrary way. According to a preferred embodiment of the invention the drain water in the tank 17 is utilized for fire fighting by the fact that it may through a conduit 36 be tapped from the tank and supplied to conduit portions, which are connected to the intake conduits 32 mentioned above and in which valves 37 are arranged. A pump 38 in the conduit 36 delivers drain water under a high pressure towards the control valves 37, and water may be directed to a desired drain water conduit 9 through a selective operation thereof. Drain water from the pump 38 may through branch conduits 39 connected to the conduit 36 be supplied to control valves 40 arranged inside the building and having a corresponding function as those indicated by 37. Further connection means 41 are present inside and outside the building and valves 42 arranged in connection thereto, through which fluid may be brought to flow to the intake conduits 32 through respective valves 37 and 40 for supply of further water or another fluid.

The cut-off valves 30 are suitably arranged in the region of the lower part of the building. The cut-off valves 30 may further be so arranged that they are selectively closed one at the time af¬ ter one of the different valves 34, 37, 40 resulting in fluid flow into the conduit 9 in question is opened. This is to say that the respective valve 34, 37, 40 may be designed as reverse valve with a cut-off valve 30 belonging thereto.

A more exact design of the floor drain 6 is illustrated in Fig 2. It has a cup-like design with an upper opening 43 restricted by a circumferential edge 44 and an outlet 45 connected to a respective conduit 9. A lid 46 is placed over the opening 43 of the floor drain in normal function thereof.

The conduit indicated by 10 in Fig 1 also appears from Fig 2, through which water from the wash basin or the like 7 may flow to the floor drain 6. This has more exactly means 47 for con- nection to the conduit 10. This means 47 is in the example illustrated as consisting of a female sleeve, in which an end of the conduit 10 may be received. The connection means 47 has also a conduit portion 48 emerging into the interior of the floor drain through a wall thereof. The wash basin 7 has suitably no water trap. The device has a fluid out-take means 49 illustrated in Fig 3, which is connectable to the floor drain 6. This means 49 is more exactly intended to form an out-take for fluid supplied to the floor drain 6 through the conduit 9. The means 49 is provided with members 50, 51 for sealed connection to the floor drain 6, so that the means 49 and the floor drain 6 together form the space arranged to receive fluid from the drain water conduit 10 and which has an outlet 52 inside the building. The means 49 has more exactly the character of a cup tumed upside down, in which the sealing 50 annularly arranged is intended to be laid against the edge portion 44 surrounding the floor drain opening 43. The means 49 has in the mid region of the annular sealing 50 an additional sealing 51 , which is also annular and has a centre hole 53 for passage of a fixing member 54. This serves for fixing the means 49 with respect to the floor drain 6. Fixing member 54 is intended to be able to engage with the floor drain 6 and influence this and the means 49 against each other, so that the sealing 50 is applied against the edge portion 44 and the sealing 51 is applied against an annular surface 104 in the region of the floor drain. This surface 104 is arranged on a hub portion 55, which is carried with respect to the floor drain 6 through spoke-like support means 56 diverging like a star. These different support means 56 have openings therebetween allowing a downwards flow of drain water and upon fluid supply an upwards flow of this fluid.

The fixing member 54 has in the example the form of a screw, the head 57 of which is intended to bear against an annular shoulder 58 in a house-like seat 59 arranged centrally in the means 49. The screw 54 is intended to engage with a threaded hole 60 carried out in the hub portion 55. A key 61 serves for tightening the screw 54, so that such sealing abutment of the floor drain 6 and the means 49 with respect to each other results in that fluid may only be taken out into the building through the outlet 53. Only one outlet 52 is indicated in the ex¬ ample, but a plurality of such outlets may of course be there. In such a case each of the outlets 52 should be connected to a valve, so that fluid may selectively be taken out through an optional outlet. Also in the case of one single outlet 52 it may be suitable to provide it with a control valve.

In order to avoid a flow of fluid to the wash basin 7 through the conduit 10 upon fluid supply to the building through the floor drain 6 and the out-take means 49 a non-return valve 62 is arranged to close against fluid flow from the interior of the floor drain 6 in the direction towards the wash basin 7 through the conduit 10. The non-return valve 62 is in the example indicated as a pivotably suspended flap valve. This could just as well consist of a ball valve. The non-return valve 62 is in the example arranged at the orifice of the conduit portion 48 into the floor drain, so that it is available for checking or a possible exchange from the inside of the cup-like interior of the floor drain. However, the non-return valve 62 allows a free flow of drain water from the wash basin 7 into the floor drain.

The device described in Figs 1-3 functions in the following way: the valves 30 are normally open while the valves 34, 37, 40, 42 are closed. The valve 19 is open, so that drain water may flow into the receiver 17. The valve 24 is closed and so is also the valve 27, and the tank 22 is filled. The container 14 is empty or in any case empty to such an extent that when the fan 11 is in operation evacuating air may flow through the conduits 9, the volume 12, the conduit 13 and the fan 11 further out of the building. When an interruption of the feeding of electricity or fire threatening conditions are detected the valve 19 is closed and the valve 24 is opened. This results in filling of the container 14 establishing a water trap as already described above. If it is a question of a fire situation the fire fighting staff may selectively supply fluid to a desired drain water conduit 9 through the intake conduit 32 belonging thereto after closing the cut-off valves 30 in question. If for example a fire is going on on floor 4, it will be suitable if the persons located there will come together in the room in which the floor drain 6 is placed. The staff may now through the respective drain water conduit 9 supply air to the room in question through the floor drain 6 placed there. Persons present in the room get thereby a supply of fresh air, which may force flue gases possibly present away. If the outtake means 49 is connected to the floor drain and the outtake means has a plurality of outlets 52 gas masks may be connected to the different outlets, so that every person present in the room may receive a direct supply of air. The staff may now for fire fighting purposes supply water through the intake conduits 32 and the drain water conduits in question after closing the cut-off valves 30 in question, for fire fighting pur¬ poses to floor drains 6 located over and/or under the floor excerted to a fire. After connection of outtake means 49 to these floor drains and switching the water feed on with a high pressure, the fire fighting staff may through fire hoses con- nected to the outlets 52 get access to great volumes of water.

In the case of a real catastrophe situation it will be possible for the fire staff to supply water through all the drain water conduits 9 for extinction almost as a flood. Initially or otherwise in situations with a lack of water the drain water in the tank 17 may be utilized for fire fighting purposes.

The embodiment according to Fig 4 corresponds mainly to the one described by means of Fig 1 with respect to the units 6 re- ceiving drain water (the floor drains) and the drain water con¬ duits 9. Thus, it is in this respect referred to the description made by means of Fig 1. Only the differences will in principle be closer described here. Such a difference consists in the fact that the additional units 62 receiving drain water in the form of wash basins here is not adapted to deliver drain water to the floor drains 6, but they are connected to a separate drain water conduit 63. This common drain water conduit 63 has a cut-off valve 64 downstream of the units 62. Between the cut-off valve 64 and the respective unit 62 a non-return valve 65 closing in the direction towards the units 62 is arranged. The drain water conduit 63 is in the embodiment illustrated here intended to not be uses for air evacuation. The conduit 63 delivers instead according to the example drain water thereof to the receiver 17 described above. This has an opening 66 for air inlet, for example above roof, so as to allow an obstacle-free drain water flow downwardly in the conduit 63. The conduit 63 has further a non-return valve 67 closing against a flow in the direction towards the opening 66.

There is also in this embodiment means for supply of fluid to the conduit 63. The fluid is here intended to be water or another liquid. As in the preceding embodiment there is a conduit 68 for supply of drain water from the receiver 17 to the conduit 63 and a pump 69 for achieving a required feed pressure is arranged in this conduit 68. There are also connection means 70 inside and outside the building. Water may be supplied to the drain water conduits 63 through these connection means. When such a water supply takes place the non-return valves 65, 67 close. The device is then preferably such that the non-return valve 65 and/or 67 manages to let air present in the drain water conduit 63 out before they close, so that the non-return valves do not close until they come into contact with water. The entire drain water conduit 63 will in this way be filled by water, which functions reducing for propagation of fire and fire gases as already described. As far as the embodiment according to Fig 4 has been described until now. the drain water conduit 63 has been filled with water from the drain water receiver 17 and from another external water source, for instance a motor fire-engine with pump equipment and water tank. However, a further possibility is also illustrated in Fig 4, namely to arrange a water tank 71 , which is connected to the drain water conduit 63 through a conduit 72. However, a valve 73 is arranged in the conduit 72. This is connected to control means arranged to normally keep the valve closed but open it upon a risk for propagation of fire and/or fire gases. Thus, the control means 74 may be controlled by temperature, smoke and/or flame detectors. The tank 71 is intended to be refilled through a conduit 75 connected to the water supply network of the building and a control valve 76 located therein.

Accordingly, the drain water conduit 63 in Fig 4 may also be filled by water from the tank 71. Thus, in a fire situation or the like the valve 64 is closed under control of the same or similar detectors as already described. The valve 73 is then opened, in which the regulation is such that the valve 73 is not opened until the valve 64 has been closed. When the valve 73 is opened water flows from the tank 71 into the drain water conduit 63. The valve 73 may then be closed if desired. The non-return valve 65 prevents water from flowing into the building through the unit 62.

The non-return valve 65 belonging to the fire cell in question or a possible further valve located between this and the cut-off valve 64 may be opened for selective water supply to the fire cell 1-5 in the building. A further valve like that is illustrated on floor 2 in Fig 4.

A possible embodiment with respect to the non-return valve 65 is illustrated in Fig 5-7. The non-return valve is there a flat valve pivotally suspended, which in the position according to Fig 6 seals against a circumferential valve seat 78. A conduit portion illustrated in Fig 5 through 63 constitutes a part of the drain water conduit illustrated in Fig 4, more exactly a branch part thereof. This branch part has means 79 for connection of the unit/the wash basin 62. These means 79 comprise a tube portion 80, inside which a tube 81 running through the unit 62 is receivable in a sealed way by means of the sealing ring 82. The tube portion 80 is securable with respect to the conduit part 63 by means of connection means 83, which may engage with corresponding connection means 84 on the conduit 63. The connection means 83 are in the example designed as a threaded sleeve engageable with the means 84 of the conduit 63 carried out as external threads. The tube portion 80 has a sealing 85, which is intended to be sealingly arranged between the tube portion 80 and the end of the portion of the conduit 63 provided with the threads 84. A conventional water trap is in this embodiment intended to be there between the conduit 81 and the very unit/wash basin 62. The embodiment, such as it appears from Figs 6 and 7, has a particular connection element 86, which comprises on one hand means 87 for connecting the connection element 86 to the portion of the drain water conduit 63 accommodating the non-return valve 65 for removing the connection means 79 described by means of Fig 5 and on the other actuating means 88 for influencing the non-return valve 65 to open in connection with mounting the connection element 86 on the conduit portion accommodating the non-return valve 65. The connection means 87 co-operates with the corresponding connection means 89 on the conduit 63. The connection element 86 has a tube-like portion 90, which is provided with connection means 91 for connection to a suitable water re¬ ceiver, for instance a fire hose intended to be used by fire fighting staff, for taking water out of the drain water conduit 63.

The connection means 87 of the connection element 86 is constituted by a sleeve provided with an intemal thread and ar¬ ranged to co-operate with the external threads 89 on the conduit 63.

When the drain water conduit 63 is to be utilized for water supply, this takes place through the conduit 68 and through the connection means 70 in Fig 4. Non-return valves 65 are then closing. If water it to be taken out at any of the units 62 the connection means 79 thereof are removed and the connection element 86 according to Fig 6 is instead applied to the conduit 63. The connection means 87, 89 are designed so that they es¬ tablish a mutual engagement before the actuating means 88 starts to act upon the non-return valve 65 for opening thereof. However, the actuating means 88 will during interconnection of the means 87, 79, in the example by turning the sleeve 87, successively force the non-return valve 65 to open, which means that water flows out of the tube portion 90 of the con¬ nection element 86 into the hose connected thereto. The connection element 86 could be provided with a closeable valve if desired.

The actuating means 88 has the character of a projecting arm located on the tube portion 90 and bears directly against the non-return valve 65.

When there is no need for water outtakes from the conduit 63 anymore the connection element 6 is removed and the connec¬ tion means 79 according to Fig 5 are replaced there again, so that the unit 62 may be used in a conventional way again.

The non-return valve 65 illustrated in Figs 5-7 may under certain circumstances be troublesome to get to react with a suf¬ ficient sensitivity, in any case when closing of the non-return valve is desired by means of filling the drain water conduit 63 from the tank 71. Thus, the flat non-return valve described could be replaced by a ball non-return valve placed in the end portion of the conduit 63.

An alternative solution to the above is to design a means 92, as indicated in Fig 8, for connection of the unit 62 receiving drain water, so that this comprises a further non-return valve 93, namely one having a greater control sensitivity than the non¬ return valve 65 first mentioned. A conduit running to the unit/the wash basin 62 is in Fig 8 as before indicated by 81. As in the embodiment according to Fig 5 the connection means 92 comprises also here connection members 83 co-operating with corresponding members 84 on the conduit 63. However, the portion between the connection members 83 and the conduit 81 of the connection means 92 is designed as a valve house 94 accommodating a ball-like valve member 95. This may move to sealing connection against a valve seat 96, so that closing takes place against a flow in the direction towards the unit 62. When drain water from the unit 62 arrives through the conduit 81 the valve body 95 assumes, however, the open position thereof illustrated in Fig 8 by continuous lines, in which the valve body is supported by support members 96 lying thereunder, which, however, leaves a water flow way past the valve body 95 and further to the conduit 63. The valve house 94 is suitably formed by two interconnected parts 97, 98, namely one 97 being connectable to the conduit 63 by means of the connection members 83 and another 98 forming a sleeve for the conduit 81.

When no fire situation is present the connection means 92 according to Fig 8 is mounted to the conduit 63 and the conduit 81 is connected to the unit 62. Drain water may then pass through the conduit 81 , through the valve house 94 and pass the valve bodies 95, 65. However, when filling of the drain water conduit 63 takes place, the more sensitive valve bodies 95 will firstly close through abutment against the valve seats 96 thereof. This is valid especially when the drain water 63 is filled from the tank 71.

When on the other hand the drain water conduit 63 is to be utilized for transporting water for fire fighting, the connection means 92 according to Fig 8 is removed and the connection element 86 illustrated in Figs 6 and 7 is instead mounted on the conduit end 63 so that the water outtake may take place through the opened non-return valve 65.

It is a matter of course that what has been described above may be modified in several ways within the scope of the inventional idea intended therefor. It may for example be pointed out that arbitrary other liquids or gases than water and air may be used for obtaining the water trap functions described and for supply to the interior of the building. Furthermore, it is pointed out that the idea of the invention defined in claim 1 may be realized without the requirement that the exhaust air means are units for receiving drain water and the conduit arrangement is adapted to transport drain water. This further development being for true advantageous appears from claim 2. It has in the example above been described how the units receiving drain water are floor drains and wash basins. Also other units receiving drain water may of course be used, for example sinks, wash receptacles, WC-chairs etc. Thus, the idea of the invention is applicable to the most different units receiving drain water. Also other modifications are possible within the scope of the following claims.

Claims (26)

Claims

1. A device at a building for preventing propagation of fire and/or fire gases, said building comprising at least two exhaust air means (6) and an arrangement (11) connected to these through a conduit arrangement (8) and generating a negative pressure, characterized in that on one hand separate first conduits (9) communicating with the exhaust air means (6) and on the other a second conduit (13) communicating with the arrangement (11) generating a negative pressure are connected to a volume (12) included in the conduit arrangement, and that the volume is formed by a container (14), which is adapted to form a liquid trap separating the first conduits (9) from each other when it is filled with liquid.

2. A device according to claim 1 , characterized in that the exhaust air means are constituted by units (6) receiving drain water, while the first conduits (9) are also adapted to conduct drain water.

3. A device according to claim 2, characterized in that the con¬ tainer (14) communicates with a receiver (17) of drain water.

4. A device according to claim 3, characterized in that a first valve (19) is arranged between the container (14) and the re¬ ceiver (17) and that this valve is connected to control means (20) arranged to normally keep the valve open but close it upon a risk of propagation of fire and/or fire gases and/or another ex¬ ceptional event, such as an electric power failure.

5. A device according to any of the preceding claims, charac¬ terized in that it comprises an arrangement (21 ) for supplying liquid to the container (14) upon a risk of propagation of fire and/or fire gases and/or other exceptional event, such as an electric power failure.

6. A device according to claim 5, characterized in that the liq¬ uid supply arrangement (21 ) comprises a liquid tank (22), a second connection (23) arranged between this and the con- tainer and a second valve (24) arranged therein.

7. A method for supplying fluid to a drain water conduit (9, 63) in a building, which drain water conduit is connected to at least a unit (6, 62) receiving drain water, characterized in that the drain water conduit (9, 63) is closed at a location being located downstream of the unit with respect to the flow of drain water, and the fluid from a fluid source (32, 68, 71 ) connected to the drain water conduit upstream of the closing location is intro¬ duced into the drain water conduit.

8. A method according to claim 7, characterized in that the fluid is supplied in such an amount that it enters into the building through the unit (6) receiving drain water.

9. A method according to claim 7, characterized in that the fluid is supplied in such an amount that it substantially com¬ pletely fills the drain water conduit (9, 63).

10. A method according to claim 8 or 9, characterized in that the fluid is a liquid, especially water, or gas, especially air.

11. A method according to any of claims 7-10, in which units (6) receiving drain water and located in different fire ceils are through separate drain water conduits (9) connected to an arrangement (14) receiving drain water and the drain water conduits (9) are closeable by means of own valves (30), char¬ acterized in that the fluid is selectively supplied to a desired fire cell through the drain water conduit (9) belonging thereto and through an intake (32) arranged therein.

12. A method according to any of claims 7-10, in which a plural¬ ity of units (62) receiving drain water are connected to one and the same closeable drain water conduit (63) and this communi¬ cates with the respective units receiving drain water through non-return valves (65, 93) closing against flow in the direction thereof, characterized in that fluid is selectively supplied to the desired fire cell through the drain water conduit part (63) running to the unit (62) receiving drain water located therein by opening the non-return valve (65) belonging thereto or another valve (77) located downstream thereof with respect to the flow of drain water.

13. A device for supply of fluid to the drain water conduit (9, 63) in a building, which drain water conduit is connected to a unit (6, 62) receiving drain water, characterized in that the cut-off valve (30, 64) is arranged in the drain water conduit and that the drain water conduit is upstream of the closing valve connected to means (32, 68, 71) for fluid supply to the drain water conduit.

14. A device according to claim 13, characterized in that the cut-off valve (30, 64) is arranged in the region of the lower part of the building.

15. A device according to claim 13 or 14, characterized in that units (6) receiving drain water located in different fire cells are through different drain water conduits (9) connected to an arrangement (14, 17) receiving drain water, that the drain water conduits (9) are closeable through own cut-off valves (30), and that each of said different drain water conduits (9) are con¬ nected to means (32) for fluid supply to the drain water conduit in question.

16. A device according to claim 13 or 14, characterized in that a plurality of units (62) receiving drain water located in different fire cells are connected to one and the same drain water conduit (63) having the cut-off valve (64) downstream of these units, and that a non-return valve (65, 93) closing in the direc¬ tion towards the unit is arranged between the cut-off valve and the respective unit.

17. A device according to claim 16, characterized in that, for selective fluid supply to a fire cell in the building, a non-return valve (65) belonging to the fire cell or an additional valve (77) located between this and the cut-off valve may be opened.

18. A device according to claim 16, characterized in that the drain water conduit is provided with an opening (66) for air inlet and that the drain water conduit has a non-return valve (67) closing against a flow in the direction towards the opening.

19. A device according to any of claims 14-18, characterized in that it has means (49) for tapping fluid connectable to at least some of the units (6) receiving drain water so as to form outlets for fluid supply to said units.

20. A device according to claim 19, characterized in that said some of the units (6) receiving drain water are floor drains.

21. A device according to claim 20, characterized in that the fluid outlet means (49) are provided with means (50, 51) for a sealed connection to the floor drains, so that the outlet means and the floor drains together form a space arranged to receive fluid from the drain water conduit and having an outlet (52) into the building.

22. A device according to claim 20 or 21 , characterized by means for connection (47) of an additional unit (7) receiving drain water to the floor drain.

23. A device according to claim 22, characterized in that the additional unit (7) receiving drain water has no water trap of its own.

24. A device according to any of claims 22 and 23, character¬ ized by a non-return valve (62) adapted to close against fluid flow from the floor drain in the direction towards the additional unit (7) receiving drain water.

25. A device according to claim 17, characterized in that it comprises a connecting element (86) comprising on one hand means (87) for connecting the connecting element (86) to a portion of the drain water conduit (63) accommodating the non¬ return valve (65) after removal of means (79) for connection of the unit (62) receiving drain water, and on the other actuating means (88) so as to influence the non-return valve to open in connection with the mounting of the connecting element on the portion accommodating the non-return valve.

26. A device according to claim 25, characterized in that the means (92) for connecting the unit (62) receiving drain water comprises an additional non-return valve (93), namely one having a greater control sensitivity than the non-return valve (65) first mentioned.