WO2005019557A1

WO2005019557A1 - A suspended ceiling and a carrier beam for a suspended ceiling

Info

Publication number: WO2005019557A1
Application number: PCT/DK2004/000556
Authority: WO
Inventors: Johnny Ostenfeldt
Original assignee: Dampa Aps
Priority date: 2003-08-21
Filing date: 2004-08-20
Publication date: 2005-03-03

Abstract

The invention relates to a suspended ceiling comprising a system of elongate beams (30) that are configured for carrying ceiling elements (10, 10’) a distance below a fixed ceiling (1’), which ceiling elements (10, 10’) comprise a metal plate (20) with sides (24, 28) and a heat-insulating plate (23, 23’). The invention is characterised in that the beams (30) are a composite structure comprising an elongate top part (50) of a material having relatively low conductivity and intended for facing towards the fixed ceiling (1’) and being fixedly connected to an elongate metallic bottom part (40) that carries the ceiling elements (10, 10’).

Description

A suspended ceiling and a carrier beam for a suspended ceiling

The present invention relates to a suspended ceiling comprising a system of particularly configured elongate beams disposed for carrying ceiling elements a distance below a fixed ceiling. The ceiling elements for such suspended ceilings conventionally comprise a metal plate with an insulating plate, preferably of mineral wool. The invention also relates to a beam for a suspended ceiling.

In particular onplate ships, where the possibilities for evacuation are limited, very strict demands are made to the fire integrity of suspended ceilings. In that context, the area between two adjoining ceiling elements, where the ceiling elements are carried by said beams, has been found to be particularly critical.

In the known suspended ceilings, such as a suspended ceiling manufactured by fa. Thermax, it has been attempted to accomplish the desired fire integrity by using a separate strip of an insulating material that spans two adjoining ceiling elements. The strip is secured along one side of the insulating plate that is a constituent of the ceiling elements.

However, the use of such strip has been found not to yield the requisite fire propagation control. Moreover, the strip gives rise to difficulties in connection with the manufacture and makes it difficult to stack the ceiling elements prior to mounting. The strip also entails that the ceiling elements have to be mounted by inclined insertion between beams which is a cumbersome operation. Moreover, it is not possible to mount the known ceiling elements by a simple downwardly oriented pull to accomplish access to the space above the suspended ceiling. The invention remedies the above-referenced problems. More specifically, it is accomplished by the beams being a composite structure comprising an elongate top part of a material having comparatively low heat conductivity, preferably mineral wool intended for facing towards the fixed ceiling and being fixedly attached to an elongate metallic bottom part carrying the ceiling elements.

The top part and the bottom part may be secured to each other by gluing or preferably by means of clamps that also establish a biasing of the mineral wool material, thereby imparting well-defined properties in respect of strength and deformations to the beam.

According to a preferred embodiment featured in claim 15, a profile in the shape of an inverted U partakes which may constitute a force-absorbing part of the beam.

Moreover, the suspended ceiling may further advantageously be configured such that the ceiling elements are secured by a clamping effect; the bottom part of the beams being preferably configured by a metal plate being bent so as to establish a longitudinally extending clamp with an insertion slit, into which the bent-up flanges on the ceiling elements can be introduced and secured.

Particularly advantageously the top part and the bottom part may have the same or approximately the same width transversally of its longitudinal expanse. Hereby the beams will appear with longitudinally extending sides, on which the sides of the insulating plates of the ceiling elements may sealingly adjoin.

Advantageous embodiments of the invention will be defined in the dependent claims. One embodiment of the invention will be explained in further detail in the following with reference to the drawing.

Figure 1 shows a ceiling element for a suspended ceiling, seen in an inclined view from above;

Figure 2 shows an exemplary known suspended ceiling, manufactured by fa. Thermax, seen in an inclined view from below;

Figure 3 is a cross-sectional view through a suspended ceiling with a beam according to the invention, seen along the line 3a shown in Figure 3b;

Figure 3b is a cross-sectional view through the suspended ceiling shown in Figure 3a, in a slightly different depiction scale;

Figure 4 shows a beam according to the invention;

Figure 5 shows a portion of the beam shown in Figure 4;

Figure 6 shows another portion of the beam shown in Figure 4;

Figure 7 shows a clamp for the beam shown in Figure 4;

Figure 8 shows the transversal beam shown in Figure 3b, and

Figure 9 shows a clamp for assembling the beams shown in Figure 3b.

Figure 1 uses the reference numeral 10 to show an exemplary ceiling element intended for being suspended a distance below a fixed ceiling in order to combine with a number of corresponding ceiling elements to form the visible ceiling face of a compartment, preferably a room onplate a ship. For instance, the ceiling element 10 may have dimensions within the range of 60 cm by 60 cm, and are intended for being carried by a system of beams secured to the fixed ceiling. The beams represent the essence of the present invention and may advantageously be configured to be compatible with the ceiling element 10 shown in Figure 1.

Such system consisting of ceiling elements and beams is usually referred to as a "suspended ceiling".

More specifically, the ceiling element 10 shown in Figure 1 consists of a metal plate 20 which is, for the sake of the acoustic properties of the ceiling element 10, provided with perforations 21 and a sound absorbing felt material 22 is provided thereon. On top of the felt material 22 a plate 23 of a heat- insulating material, such as mineral wool, is provided. The metal plate 20 has bent-up flanges 24, 28 along its sides, and the flanges 24 are used to attach the ceiling element 10 to said system of beams. The plate 23 of the heat- insulating material serves the important purpose of providing fire propagation control from the subjacent compartment to other compartments situated above; as the ceiling element must - to achieve the requisite approval from the fire authorities - be able to safeguard against excessive temperatures occurring in the area between the suspended ceiling and the fixed ceiling for a given period of time in case of a fire in the subjacent compartment.

Figure 2 shows the prior art suspended ceiling referred to above and arranged underneath a fixed ceiling 1 '. A number of parallel beams 30' carry the ceiling elements 10' that consist of a perforated metal plate 20' carrying a plate 23' of a heat-insulating material. The beams 30' are configured as an inverted T and the edges of the metal plate 20' rest on the outwardly protruding flange of the beams 30'. When a ceiling element 10' is to be mounted between two beams 30', the ceiling element 10' is kept inclined as shown, is taken between the beams 30' and is subsequently lowered to the effect that the edges of the metal plate 20' rest on the beams 30'.

In particular onplate ships where the possibilities for evacuation are limited very strict requirements are made to the fire integrity of suspended ceilings. In that context, the area between two adjoining ceiling elements where the ceiling elements rest on the carrier beams has been found to be particularly critical. In order to ensure that a high heat-insulating capacity is also provided in the area between the two adjoining ceiling elements 10' shown in Figure 2, each plate 23' of the heat-insulating material is therefore, along the one edge, provided with a separate strip 50' of the heat-insulating material in question. The strip 50' extends beyond the edge of the plate 23' and is secured by gluing to the top face of the plate 23'. When the ceiling element 10' is lowered into position, the strip 50' rests on the top face of the adjoining ceiling element, ie against the top face of the adjoining plate of insulating material. So far, practice has shown that this is the only way to achieve the high heat-insulating capacity and hence the good fire integrity. The use of said strip 50' gives rise to difficulties of manufacture and makes it difficult to stack the ceiling elements 10' in a compact manner prior to mounting. Moreover the strip 50' means that the ceiling element must necessarily be mounted in the shown manner, ie by inclined insertion between the beams 30', which is a cumbersome operation. Moreover, the strip 50' means that it is not possible to dismount the ceiling elements 10' by a simple downwards pull to achieve access to eg the piping installation shown in the space above the suspended ceiling.

Figure 3a shows a cross section along the line 3a shown in Figure 3b through a part of a suspended ceiling constructed by use of the beams according to the invention and the ceiling elements 10 shown in Figure 1. In the drawing, the beams according to the invention are generally referred to by the reference numeral 30. The suspended ceiling may optionally be connected to the superjacent fixed ceiling via wires that are connected directly to the beams 30, but it is preferred that the suspended ceiling comprises the beams 30 and a number of transverse beams 80, shown in Figure 3b, and to which said wires are connected. Thereby the ceiling elements 10 are carried by the beams 30 that are, in turn, carried by the beams 80.

Figure 3a shows the suspended ceiling following arrangement of two adjoining ceiling elements 10 to be carried by the beam. In the shown embodiment the beam 30 comprises two resilient legs 41 that define between them a longitudinal receiving slit 42 for the flanges 24 of the ceiling elements 10. As shown, the flanges 24 are preferably, but not necessarily, provided with a profile to enable the flanges 24 to be secured in the receiving slit 42 by means of the resilient legs 41 , after having been pressed into the receiving slit 42 against the force of the resilient legs 41 that seek to keep the receiving slit 42 closed.

As will appear more clearly form Figure 4, the elongate beams 30 according to the invention constitute a composite structure in the form of a bottom part 40 manufactured by bending of an elongate metal plate and preferably being secured to a top part 50 in the form of a strip of an insulating material, preferably mineral wool, having essentially the same length and width dimensions as the bottom part 40.

As shown in Figure 3a, the beams 30 preferably have approximately the same height as the ceiling elements 10; the height of the top part 50 preferably being selected such as to accomplish approximately the same heat-insulating properties in the area at the beam 30 as is the case interiorly of the ceiling element 10, ie to the effect that the heat-transmission remains essentially the same between the bottom side and the top side of the suspended ceiling, irrespective of which area of the suspended ceiling is concerned. In order to ensure such uniform heat-transmission properties, ie to compensate for the slightly reduced thickness of the insulating material, it is an option to use another insulating material having a lower heat- conductivity for the top part 50 of the beams than the insulating material used for the ceiling elements 10.

The bottom part 40 of the beams 30 is shown in further detail both in Figure 4 and Figure 5, and it will appear that the bottom part 40 comprises a flange 43, from where two parallel legs 41 are formed by bending of the metal plate, said legs converging towards each other and forming between them the insertion slit 42 and each having a lower edge 44 extending from the insertion slit 42. Immediately below the flange 43 and on both sides, an abutment edge 46 is formed, the object of which will be explained in further detail.

The top part 50 of the carrier beam, made of an insulating material, preferably mineral wool, is shown in further detail in Figure 6, the drawing also showing an inversed, U-shaped element 60 formed by bending of a metal plate and preferably extending across the longitudinally extending top face 53 of the top part 50 and down across a part of the sides 52 of the top part 50. The U-shaped element 60 has a bottom 62 and sides 61 that abut closely on the top face 50. When the top part 50 is manufactured from mineral wool, it can advantageously be somewhat oversized relative to the U- shaped element 60 to the effect that, in connection with the mounting in the production facility of the U-shaped element 60, a compression of the top part 50 takes place. Preferably the top part 50 has a rectangular cross section, whereby the faces 52 of the top part are flush with the sides 25 of the heat- insulating plate 23 of the ceiling elements 10, as shown in Figure 3a. The U- shaped element 60 contributes to the flexural strength of the beam 30 and to ensuring adequate transmission of force between the beam 30 and the transverse beams 80. Preferably the insulating material has a heat conductivity λ of a magnitude of 0,037 W/m°C, being thus considerably lower than that of the bottom part 40. If mineral wool is used, a density is also preferred within the range of 175-225 kg/m³, preferably such that the top part 50 becomes relatively hard.

For manufacturing the beam 30, the bottom part 40 is secured to the top part 50 in the production facility eg by application of glue onto the top face of the flange 43 and on the top face 51 of the top part 50 and subsequently joining these surfaces. Alternatively, or complementarily, the attachment may take place by means of a number of metal clamps 70 that seize around the top part 50 and the bottom part 40. An example of such clamp 70 is shown in detail in figure 7, and the clamps 70 are disposed at a mutual distance along the beam 30 as shown in Figure 3b. Preferably the clamps 70 are configured with a U-shaped cross-section, the legs 71 of the U, converging towards each other, having gripper arms 74 that can be locked onto the bottom part 40 by seizing underneath the flange 43 and abutting on the abutment edge 46, as shown in figure 3a. In that position the bottom 72 of the clamp 70 abuts on the bottom 62 of the U-shaped element 60 and thereby secures the top part 50 in abutment against the bottom part 40, preferably while establishing some degree of biasing force in the insulating material that constitutes the top part 50. Where mineral wool is used as insulating material in the top part 50, the mounting of the clamps 70 may thus give rise to a certain compression of that material other that the compression optionally imparted by the mounting of the U-shaped element 60. The compression gives rise to well-defined strength properties of the beam 30.

Figure 8 provides further details of the transverse beam 80 shown in figure 3b. The beam 80 is, as described above, preferably suspended in the fixed ceiling by means of wires, following which the beams 30 are secured to the beams 80. Alternatively the beams 30 and 80 can be connected to each other while sitting on the floor, following which the assembled beam structure is raised to the desired height relative to the fixed ceiling and secured at this height by means of wires connected to the beams 30 or preferably to the beams 80 that may be configured with a higher degree of rigidity than the beams 80. The beam 80 has a U-shaped cross-sectional shape with a bottom 81 and two lateral flanges 82, each of which has outwardly bent flanges 83.

When the beams 30 are secured to beams 80, the bottom 81 of the beam 80 adjoins, as is shown in Figure 3b, the top face of the bottom 62 of the U- shaped element 60 or, if the top face 50 of the beam 30, is not provided with the U-shaped element 60, the top face 53 of the top part 50.

This attachment is accomplished in an intersection between the beams 30 and 80 by means of eg the two resilient clamps 90 shown in figure 3b and 9 and configured to being, on the one hand, in engagement with the beam 30 and, on the other, to adjoining the top face of one of the outwardly bent flanges 83 of the beam 80. Preferably the clamps 90 are configured from a metal wire with two ends 97 that can be pressed into the sides 52 of the insulating material of the top face 50 when the material is mineral wool, immediately below the longitudinally extending lower edge of the side 61 of the U-shaped element 60. Hereby a kind of hinge connection is provided, and the beam 80 can be secured to the beam 30 by the fitter subsequently pivoting the clamps 90 to the position shown in figure 3b, in which a part 83 of the clamp 90 abuts on the outwardly bent flange 83 of the beam 80 following an preceding deformation of an area 94 of the clamps 90, so as to provide an attachment force. Moreover, the clamp 90 has a portion 91 , by which the clamp 90 can be operated by hand - either with the object of pivoting the clamp to the position shown in figure 3b, or with the object of releasing the clamp 90 from its engagement with the outwardly bent flange 83. Albeit the bottom part 40 of the beam 30 is shown with a receiving slot 42 to receive the flanges of the ceiling element 10, such receiving slot is not compulsory for obtaining the properties intended for the invention. Thus, the bottom part 40 may very well be configured with eg an H-shaped cross- section, ie with parallel horizontal flanges or with any other cross-section that enables attachment of the top part 50 and also contains abutment faces for simple support of the sides of the ceiling elements 30, 30', eg as explained above with reference to Figure 2.

It should be emphasised that the beam 30 shown in Figure 4 will also be suitable for supporting ceiling elements without flanges that are readily suitable for being inserted and secured in the receiving slot 42. The outwardly projecting lower edges 44 thus form abutment faces that could be used for supporting such ceiling elements in a position in which the sides 25 of the plate-shaped insulation of the ceiling elements adjoin the longitudinally extending sides 52, 61 of the top part 50 without thereby departing from the invention. However, the particular advantage is accomplished by use of beams having the configuration shown eg in Figure 5, ie where the beams have an insertion slit delimited by resilient elements in combination with ceiling elements having upwardly bent edge flanges 24, since it is hereby possible to mount the ceiling elements with an upwardly oriented movement without an ensuing need for the inclined introduction between the beams described above. Simultaneously that solution enables dismounting of the beam elements by application of a downwards pull onto the ceiling elements - eg by means of a number of suction cups.

Claims

C l a i m s

1. A suspended ceiling comprising a system of elongate beams (30) that are configured for carrying ceiling elements (10, 10') a distance below a fixed ceiling (1'), said ceiling elements (10, 10') comprising a metal plate (20) with sides (24, 28) and a heat-insulating plate (23, 23'), characterised in that the beams (30) are a composite structure comprising an elongate top part (50) of a material with a relatively low heat conductivity intended for facing towards the fixed ceiling (1') and fixedly attached to an elongate metallic bottom part (40) that carries the ceiling elements (10, 10').

2. A suspended ceiling according to claim 1 , characterised in that the material with low heat conductivity is mineral wool.

3. A suspended ceiling according to any one of the preceding claims 1 or 2, characterised in that the top part (50) and the bottom part (40) are attached to each other by means of glue.

4. A suspended ceiling according to any one of the preceding claims, characterised in that the top part (50) and the bottom part (40) are secured to each other by means of clamps (70).

5. A suspended ceiling according to the preceding claim, characterised in that the clamps (70) are configured with a generally U-shaped cross-section with a bottom (72) and sides (71 ) that extend around a part of the top part (50), the sides (71 ) along the free edges having gripper arms (74) engaging with the bottom part (40).

6. A suspended ceiling according to any one of the preceding claims, characterised in that the material with low heat-conductivity is compressed.

7. A suspended ceiling according to any one of the preceding claims, characterised in that the ceiling elements (10, 10') between the metal plate (20) and the heat-insulting plate (23, 23') carries a sound-absorbing felt material (22); and that the metal plate (20) comprises a number of perforations (21 ).

8. A suspended ceiling according to any one of the preceding claims, characterised in that the heat-insulating plate (23, 23') has sides (25) that abut against the top part (50).

9. A suspended ceiling according to any one of the preceding claims, characterised in that the top part (50) and the bottom part (40) have essentially the same width transversally of the longitudinal direction of the beam (30).

10. A suspended ceiling according to any one of the preceding claims, characterised in that the metal plate (20) comprises an upwardly bent flange (24, 28) along at least one side.

11. A suspended ceiling according to the preceding claim, characterised in that the bottom part (40) comprises a clamp (41 , 42) that extends along the beam (30) for securing the upwardly bent flange (24, 28).

12. A suspended ceiling according to any one of claims 1-10, characterised in that the bottom part (40) comprises an abutment face (44) on which the ceiling elements (10, 10') can rest in order to thereby be carried by the beams (30).

13. A suspended ceiling according to any one of the preceding claims, characterised in that the bottom part (40) has a longitudinally extending flange (43) in contact with the top part (50).

14. A suspended ceiling according to any one of the preceding claims, characterised in that the bottom part (40) is formed by bending of a metal plate.

15. A suspended ceiling according to any one of the preceding claims, characterised in that the top part (50) also comprises a longitudinally extending inversely U-shaped element (60) that defines the top face (62) of the top part (50) and at least a part of the sides (61 ) of the top part (50).

16. A suspended ceiling according to any one of the preceding claims, characterised by a further number of beams (80) extending essentially at right angles on top of the beams (30); and being connected to the beams (30) in a releasable manner by means of clamps (90).

17. A suspended ceiling according to the preceding claim, characterised in that the top part (50) is manufactured from mineral wool and is secured interiorly of the inversely U-shaped element (60), compressing the mineral wool.

18. A suspended ceiling according to any one of the preceding claims, characterised in that the top part (50) is manufactured from mineral wool; that the clamps (90) are made of a metal wire; and that the ends (97) of the metal wire are pressed into the mineral wool in abutment against the inversely U-shaped element (60).

19. A beam for carrying, in a suspended ceiling, ceiling elements (10, 10') that comprise a metal plate (20) with sides (24, 28) and a heat-insulating plate (23, 23') a distance below the fixed ceiling (1'), characterised in that the beam (30) is a composite structure comprising an elongate top part (50) of a material having a relatively low heat-conductivity intended for facing twoards the fixed ceiling (1'), and being securely connected to an elongate metallic bottom part (40) comprising means (42, 44) for carrying the ceiling elements (10, 10').

20. A beam according to claim 19, characterised in that the mineral with low heat conductivity is mineral wool.

21. A beam according to any one of the preceding claims 19 or 20, characterised in that the top part (50) and the bottom part (40) are secured to each other by means of glue.

22. A beam according to any one of the preceding claims 19-21 , characterised in that the top part (50) and the bottom part (40) are secured to each other by means of clamps (70).

23. A beam according to the preceding claim, characterised in that the clamps (70) are configured with a generally U-shaped cross-section with a bottom (72) and sides (71) that extend around a part of the top part (50), the sides (71 ) along the free edges having gripper arms (74) engaging with the bottom part (40).

24. A beam according to any one of the preceding claims 19-23, characterised that the material with low heat conductivity is compressed.

25. A beam according to any one of the preceding claims 19-24, characterised in that said means (42, 44) are constituted by a clamp (41 , 42) extending along the bottom part (40) for securing an upwardly bent side (24, 28) of the ceiling element (10).

26. A beam according to any one of the preceding claims, 19-24, characterised in that said means (42, 44) are constituted by an abutment face (44) extending along the bottom part (40), on which one of the sides (24, 28) of the ceiling element (10, 10') can rest in order to thereby be carried by the beam (30).

27. A beam according to any one of the preceding claims 19-26, characterised in that the bottom part (40) has a longitudinally extending flange (43) in contact with the top part (50).

28. A beam according to any one of the preceding claims 19-27, characterised in that the bottom part (40) is formed by bending of a metal plate.

29. A beam according to claims 25 and 28, characterised in that the clamp is an integral part of the bottom part (40) and comprises an insertion slit (42) delimited by resilient legs (41 ) that are connected to each other by means of a flange (43), by which the bottom part (40) is fixedly secured to the top part (50).

30. A beam according to any one of the preceding claims 19-29, characterised in that the top part (50) also comprises a longitudinally extending inversely U-shaped element (60) that defines the top face (62) of the top part and at least a part of the sides (61 ) of the top part (50).