GB2245010A

GB2245010A - Suspended ceiling support grid

Info

Publication number: GB2245010A
Application number: GB9013147A
Authority: GB
Inventors: Anthony Stuart Pitkethly
Original assignee: DAMPA
Current assignee: DAMPA
Priority date: 1990-06-13
Filing date: 1990-06-13
Publication date: 1991-12-18
Anticipated expiration: 2010-06-13
Also published as: GB2245010B; GB9013147D0

Abstract

A grid for supporting suspended ceilings comprises interfitting grid sections (10) for supporting ceiling panels (11). The sections (10) each have a downwardly opening channel (1) to receive screws for fixing partition panels to the grid. The sections (10) are interfitted by mitre joints of the end of each section (10) such that the grid has a continuous channel system and the joints include means (9) to hold the joined sections (10) together. The holding means (9) may be a connector having arms arranged to engage the joined sections (10) in press fitment. <IMAGE>

Description

STRUCTURE The present invention relates to suspended ceiling systems.

Suspended ceilings are known in which the ceiling panels are held in a support grid which is in turn suspended from above. The interior partitions of a building with a suspended ceiling must be connected to the suspended ceiling, and this has neatly been achieved by providing the grid structure with threaded channels in which may be screwed fixing screws for holding partition panels to the suspended ceiling.

One such structure is described in GB-B-2152091. The support grid of GB-2152091 comprises sections with channels formed in their bottoms for receiving fixing screws. The grid sections are joined together by mitre joints such that a continuous channel system is formed throughout the grid, without discontinuities between the channels of different grid sections. The support grid comprises long sections which extend the length of the grid in one direction, and short sections which extend at right angles to the long sections and are fitted between adjacent long sections so that there are formed square openings in which the ceiling panels are held.Except at the corners, the short sections are joined to the long sections by double mitre joints; for this purpose the channels of the long sections are opened to form female mitre joints (also called "bird's mouths") in which are received the male ends of the short sections.

An attractive feature of the support grid of GB-2152091 is the use of long structural sections which extend the length of the grid in one direction. The avoidance of joints in one direction of the grid provides a certain structural integrity to the suspended ceiling and facilitates construction. The grid assembly of GB-2152091 has therefore found favour with architects and installation contractors.

We have now devised a support grid for suspended ceiling panels which has a continuous channel system for receiving fixing fasteners for partition panels, which does not have any sections or members extending the length of the grid and yet which surprisingly represents an improvement over the system of GB-2152091. This grid is characterised in that the individual sections of the grid are joined by mitre joints at the ends of the sections and are interconnected at the joints.

A preferred support structure included in the invention is a grid comprising interfitting grid members or sections which support the ceiling panels in the assembled suspended ceiling. A continuous channel extends the length of the grid sections for receiving partition fixing fasteners; the channels desirably have threaded or fluted side walls for engaging the thread of the fixing screws. In order to provide the support structure with a continuous channel system, the individual members engage one another at mitre joints. The interfitting members of the mitre joints are the ends of grid sections, so that grid sections do not have joints intermediate their ends. At the joints, means is provided for holding the members of the joint together.

The means for holding the joint members together preferably comprises male and female structures which interengage by press fitment; normally one of those structural types is provided on the joint members while the complementary structure is provided on a separate connector, and for simplicity the same type of structure may be provided on all the joint members.

Thus the joint members can conveniently be held together by means engaging a groove or slot in the members. In practice, this can readily be achieved by making the members generally in the form of a box and providing a connector having an arm to be push fitted into the open end of each member. The connector at a joint thus has arms appropriate in number and orientation to the number and orientation of the joint members.

In another aspect, the invention resides in a suspended ceiling support grid joint. Typically, the joint is of the mitre type. The members of the joint can all be the ends of grid sections but the joint can include a member which is an intermediate portion of a grid member section. The joint members may be of the type having a channel for receiving partition fixing screws or fasteners. The joint may be a mitre joint. The members of the joint are held together by press fitment of each with a holding means. In one embodiment, the members of the joint all contain a recess in each of which engages an arm of a connector. The connector is press or push fitted into the recesses so that no tools need be used to form the joint, although additional fixing means (e.g. screws) might be desired in some instances.

Another preferred joint structure encompassed by the invention is a suspended ceiling support grid joint of the mitre type. Desirably, this joint is composed of members all of which are grid sections of the type having a channel for receiving partition fixing screws. The joint is a mitre joint such that continuity in the channel system is provided at the joint and joins together the ends of three or more grid members, that is none of the interengaging parts forming the joint is an intermediate portion of a grid section. Usually, the members of the joint are held together e.g. by interengagement of male and female structures as described above and especially by the push fitting of an arm of a connector into the interior of members of box construction, or otherwise by engagement of holding means in a groove or similar recess in each joint member.

Whilst this invention may seem retrograde with respect to that of GB-2152091, it is important to stress that it does in fact offer numerous advantages each of which represents a useful improvement over all the suspended ceiling grids and grid joints of which we are aware.

One of the advantages of our invention is that a support grid can be constructed to fit most buildings using standard grid sections. In the grid of GB-2152091, the long sections which run the length of the grid must be machined to the required length in the factory. In contrast, our grid can be made to suitable dimensions simply by using an appropriate number of standard grid sections. In this respect, we have found that grid sections with a length from tip to tip of 60cm provide a versatile system which can be satisfactorily installed in most buildings without any need to especially machine sections to other lengths. This makes manufacture of the grid sections more economical and also avoids the administrative burden on the installation contractor and manufacturer imposed by the need to machine sections to length. Versatility can be enhanced by providing the sections in more than one standard length.

The grid sections of GB-2152091 are not coupled together in any fashion at the point of interengagement, but are held in position by the suspension system. Although the use of continuous grid sections in one direction helps maintain structural integrity whilst simultaneously reducing the number of interfitments to be made and the number of individual sections to be handled, the system has in practice been unsatisfactory in the respect that the grid sections sometimes separate where they fit together. In the present invention this problem can be overcome by holding together the grid sections at the joints, for example by a simple system requiring only press fitting of a connector into a slot in each grid section.Paradoxically, the interholding of the grid sections, although apparently making assembly of the grid more difficult, can actually facilitate it by accurately locating the ends of the grid sections with respect to one another.

The present invention is further described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a cross-section through a member of a suspended ceiling support grid; Figures 2 and 3 are views along arrow A showing single mitre and double mitre ends, respectively; Figures 4, 5 and 6 are plan views of a corner joint, a cruciform joint and a T-joint, respectively; and Figure 7 is a cross-section through a portion of a suspended ceiling structure.

In Figure 1 there is shown a cross-section through a section or member 10 of a grid for supporting suspended ceiling panels. The grid section 10 has formed in its bottom a channel 1 which can receive screws for fixing partition panels to the grid when it is installed. To this end, the downwardly opening channel 1 has side walls 2 which are threaded (fluted) to engage the thread of a fixing screw.

As shown in Figures 2 and 3, the channel 1 is continuous along the section. The section 10 of Figure 2 has a double mitre structure 3 at each end, whereas that of Figure 3 has a single mitre structure 4 at each end. Of course, a section may have a double mitre at one end and a single mitre at the other.

Reverting now to Figure 1, it will be noted that the grid section 10 is provided with a surface 5, shown at the top of the section, on which the edge of a ceiling panel can be seated as shown in Figure 7 (which will be described later).

The grid section is in the form of a box which is open at the top. At the top of the grid section 10 inwardly opening slots 6 are formed which extend the length of the section.

Other features of interest in the grid section 10 are internal, downwardly facing shoulders 7 formed in the sidewalls of the section 10. The shoulders 7 are spaced above a generally opposed (i.e. upwardly facing) surface 8 formed by the cross-wall of the channel 1. Structure 9 is not part of the grid section 10 and will be described later.

As is customary, the illustrated grid section 10 is made of extruded aluminium.

The double and single mitre constructions shown respectively in Figures 2 and 3 can be fitted together to form a corner joint (Figure 4), cruciform joint (Figure 5) or T-joint (Figure 6), depending on the particular combination of section ends used.

It will be noted in the Figures that the sections 10 forming the joints abut along planes oriented in a direction perpendicular to the plane of the paper of the drawings.

This direction is the same as that of the direction in which the channels 1 open and, consequently, the mitre joints provide aesthetically pleasing continuity of the channel system.

To provide structural integrity and ensure that the joints do not open, connector 9 shown in dotted lines in Figures 4 to 6 is provided. Connector 9 is normally made of aluminium.

The connector 9 of a joint has arms arranged to engage in the grid sections 10 which form the joint. The location of the arm of a connector 9 in a grid section 10 can be seen with the aid of Figure 1. The arm engages in the interior of the box section and is held in place between shoulders 7 and opposed surface 8 and between the opposed side walls of the box structure. These opposed surfaces effectively define a slot in which the connector 9 is press fitted.

In the Figures, the arms of the connector 9 are shown to consist of a single plate but any other arrangement capable of being press fitted in a grid section 10 will serve, e.g.

a pair of prongs.

In the illustrated embodiment, the connector 9 is concealed in the grid when installed by the cross-wall of the channel 1. This is a desirable feature but not essential and, in an alternative embodiment, the arms of the connector 9 are gripped in the channel 1 at its base or in another recess provided in the grid section 10.

The joints are easily assembled by sliding the arms of the connector 9 into the box of each grid section 10 or other slot or recess in which the respective arm is engaged. The connector 9 serves not only to prevent the joint opening but also to locate the grid sections 10 with respect to each other.

It will be appreciated that the illustrated joint structure is only exemplary and that it may be modified to provide any arrangement in which the sections 10 are held together by press fitting of male and female members, whereby the joints can readily be assembled without the need for tools.

Normally the sections 10 are held through the intermediary of a connector which engages each section 10 of the joint.

A number of novel aspects are exemplified in the Figures.

Figures 5 and 6 show a novel suspended ceiling support grid joint which is a mitre joint whose members are the ends of three or more grid sections 10. This novel joint desirably includes means to hold the members thereof together and linked to the use of a mitre joint is the preferred provision in the grid sections 10 of a channel for receiving partition fixing fasteners; continuity of the channel system is achieved at the joint by using a mitre joint of which the planes of abutment are oriented in a direction which is the same as the direction of opening of the channel system.

Figures 4 to 6 all illustrate a novel joint between sections 10 of a suspended ceiling support grid in which the sections are held together by each being in press fitting engagement with a connector. This joint structure can be adapted for use with, for example, the grid sections shown in GB-2152091, such as by fitting the connector in the threaded channels of the sections.

Figure 7 shows a grid section 10 in place in a suspended ceiling installation. The grid sections 10 are assembled to form a grid in which the sections define square apertures in which panels 11 are supported by sections 10.

The sections 10 are suspended in known manner by suspension member 12 in the form of an inverted "T", the edges of the crossbar of the "T" being engaged slidingly in slots 6 of grid section 10.

If desired, rectangular (oblong) rather than square panels 11 can be used by selecting sections of different lengths for the two perpendicular directions. Indeed, it is in principle possible for a non-rectilinear construction to be made.

The illustrated joints may be used, therefore, to form a suspended ceiling support grid comprising interfitting grid sections 10 for supporting ceiling panels 11, wherein the sections have a continuous, usually threaded (fluted), channel 1 extending along their lengths and designed to receive partition fixing fasteners, the points of interfitment of the grid sections 10 are the ends of the sections 10, the section ends are interfitted by mitre joints whereby the grid has a continuous channel system and the joints include means 9 to hold the members thereof together.

It will be noted that, unlike the male grid sections of GB-2152091, the section of Figure 2 is not significantly truncated at its ends. A section 10 having a double mitre construction of the type illustrated in Figure 2 is accordingly believed to be novel and, therefore, included in the invention is a suspended ceiling grid section at least one end of which is tapered on opposed sides to a point, whereby a double-mitre construction is formed, and which has extending continuously therealong a channel desirably having threaded side walls, the channel opening in a direction such that when the section is viewed in plan in a direction aligned with the opening of the channel, the double taper is also seen in plan view. The other end of the section may taper on one side or on both sides.

Another novel feature illustrated in Figure 7 is seal 13 disposed in one of the external recesses formed on the sides of the section 10. The seal 13 acts as an acoustic seal and/or vibration damping element between the section 10 and the panel or tile 11. In the illustrated embodiment, the seal 13 consists of an elongate strip of resilient material extending the length of the section 10, but a discontinuous seal 13 is also encompassed by the invention.

A number of materials are available on the market for different sound proofing or vibration damping purposes. We normally use a closed cell cross-linked polyethylene foam strip. The seal 13 is desirably self-adhesive on one side so that it can be conveniently secured to the section 10, but other methods of securement may be used, if desired. We prefer that the seal 13 be made of a compressible material and that its uncompressed thickness- be greater than the depth of the recess in which it is disposed. In this way, the seal 13 protrudes beyond the lateral surface of the section 10 until it is compressed by the panel 11 to be generally flush with the surface.

A seal 13 may be installed in one or both of the external lateral recesses or grooves of any grid section 10, as desired.

Another preferred embodiment of the invention, therefore, is the use of an acoustic seal or anti-vibration mounting between a suspended ceiling panel or tile and means supporting the panel. The seal is desirably made of foam plastics material or other compressible material . The seal may be continuous or discontinuous. It may form a bridge excluding all direct contact between the panel and the supporting means or it may form a bridge between only a portion of the juxtaposed surfaces of the panel and the support, leaving some direct contact. If compressible, the seal may be in a compressed state between the panel and the support.

The supporting means for the panel may be a -section of a support grid and may be disposed in a recess in the section so as to contact only a portion of the opposed surface of the panel. The invention includes a support grid for a suspended ceiling in which there are provided acoustic seals or anti-vibration mountings to be located between the grid and the supported panels.

Claims

1. A suspended ceiling support grid joint, wherein the members of the joint are the ends of three or mo '- grid sections each of which has extending therealong a continuous channel for receiving partition fixing fasteners, the joint is a mitre joint such that a continuous channel system is formed at the joint, and the joint includes means to hold the members thereof together.

2. A joint as claimed in claim 1, wherein the channel has threaded side walls.

3. A joint as claimed in claim 1 or claim 2, wherein the means to hold the grid sections together comprises a connector with which each joint member is connected.

4. A joint as claimed in claim 3, wherein the grid sections are connected with the connector by press fitment.

5. A joint as claimed in claim 4, wherein the connector has arms which engage in complementary recesses in the grid sections.

6. A joint as claimed in claim 5, wherein the grid sections are of open-ended box structure and the connector arms engage in the interiors of the grid sections through the open ends thereof.

7. A joint as claimed in claim 6, wherein each grid section comprises a bottom wall in which the continuous channel is formed and side walls which extend upwardly from the side edges of the bottom wall to an open top of the box structure, the channel being located generally centrally between the side edges of the bottom wall and having a cross wall at its top which joins the inner (i.e. top) ends of the channel side walls, and the side walls of the grid section each having a downwardly facing internal shoulder spaced above the cross wall of the channel, the respective arm of the connector being engaged between the shoulders and the cross wall of the channel.

8. A suspended ceiling support grid comprising interfitting grid sections for supporting ceiling panels, wherein the sections have extending therealong a continuous channel for receiving partition fixing fasteners, the grid sections are interfitted at their ends by mitre joints such that the grid has a continuous channel system and the joints include means to hold the members thereof together.

9. A grid as claimed in claim 8 wherein the channels in the sections have threaded side walls.

10. A grid as claimed in claim 8 or claim 9 wherein the arrangement at the joints is as further defined in any one of claims 3 to 5.

11. A grid as claimed in claim 10 wherein the grid sections are as further defined in claim 6 or claim 7 and the arrangement at the joints is as further defined in the respective one of those claims.

12. A grid as claimed in claim 11, wherein the grid sections and joint arrangements are as further defined in claim 7 and the grid sections have in each side wall thereof a longitudinally extending inwardly opening slot spaced above the internal shoulder of the side wall and opposed to the longitudinal slot in the opposite side wall, the slots in each grid section being for receiving a suspension member for suspending the grid from a building.

13. A joint between sections of a suspended ceiling support grid in which the sections are held together by each being in press fitting engagement with a common connector.

14. A joint as claimed in claim 13 wherein the joint is a mitre joint.

15. A joint as claimed in claim 14, wherein the sections have extending therealong a continuous channel, optionally with threaded side walls for receiving partition fixing screws, and the joint is a mitre joint such that a continuous channel system is formed at the joint.

16. A suspended ceiling support grid joint whose members are held together at the joint and which is substantially as hereinbefore described with reference to or as illustrated in the accompanying drawings.

17. A suspended ceiling support grid whose sections are held together at the joints and which is substantially as hereinbefore described with reference to or as illustrated in the accompanying drawings.

18. A suspended ceiling grid section at an end of which opposed sides taper to a central point and which has extending centrally therealong a continuous channel, the channel opening in a direction such that, when the section is viewed in plan in a direction aligned with the direction of opening of the channel, the double taper is also seen in plan view, the other end of the section being tapered on one or both sides.

19. A section as claimed in claim 18 wherein the channel has threaded side walls.

20. A section as claimed in claim 18 or claim 19 which has formed at each end a recess which in use receives a press fitted connector.

21. A section as claimed in claim 20 which is of open-ended box construction and the open ends of the box form the recesses.

22. A section as claimed in claim 21 and as further defined in claim 7.

23. A suspended ceiling grid section at least one end of which has the tapered design of the ends illustrated in Figure 2 and which is substantially as hereinbefore described with reference to or as illustrated in the accompanying drawings.

24. An acoustic seal or anti-vibration element disposed between a suspended ceiling panel and means supporting the panel.

25. A support grid for a suspended ceiling in which there are provided acoustic seals or anti-vibration mountings to be located between the grid and supported panels.