EP0590213A1

EP0590213A1 - System for fitting plaster slabs

Info

Publication number: EP0590213A1
Application number: EP92500125A
Authority: EP
Inventors: Agustin Aldanondo Pellicer
Original assignee: YESOS ESCAYOLAS Y DERIVADOS SA
Current assignee: YESOS ESCAYOLAS Y DERIVADOS SA
Priority date: 1992-10-02
Filing date: 1992-10-02
Publication date: 1994-04-06

Abstract

The plaster slalbs(1), to be employed in the formation of false ceilings,are provided in their edges with small grooves (2-3), which, in side engagement between slabs at the same level, define openenings with an intermediate step, which corresponds to the securing point of the slabs,engagement which is made by means of a threaded rod (4) secured to the frame (5) by a top rocker arm (6) and a nut-washer set (7-8); said threaded rod including also two other nut-washer sets; an intermediate one (9-10) forming a positioning stop and a lower one (11-12) which is the real fixing element, and which is fixed in the step of the openings defined between slabs, and which, after being definitively engaged, remains unseen by a plaster filling, which is at the same level as the bottom surface of the slabs (1).

Description

SUBJECT OF THE INVENTION

This invention refers to a new system for the fitting of plaster slabs, particularly designed for false ceilings which, apart from its great operative simplicity and while remaining dismountable, makes it possible to place the plaster slabs as close as possible to the frame of the room, with the resulting space saving.

BACKGROUND TO THE INVENTION

It is already well-known in the building construction field, particularly for the suitable finish of ceilings, that one of the commonly-used solutions is to dress such ceilings with plaster which is then painted.
There are two alternatives for such dressing: one is fixed, usually employing a lattice of cane which is secured to the ceiling with a mass of gypsum or plaster: the plaster slabs are then, similarly, secured to the cane lattice so that they are immobile. This solution is falling ever more into disuse because of its high manpower content, with very specialized personnel: in addition, the system also creates significant problems when access is subsequently necessary to the gap formed over the false ceiling for repairs or for any other reason, since it is then necessary to break the plaster false ceiling, causing major damage which requires more specialized personnel for its complete restoration.
Because of these problems, when a false ceiling is to be created, e.g. to conceal all types of ducting under the frame, the solution adopted is to use structures making it possible to remove the slabs easily. One of the most commonly used solutions here is to create a reticular mesh whose dimensions are in line with the size of the plaster slabs to be used, based on inverted "T" profiles which are secured to the frame over the ceiling to be covered, so that the plaster slabs can be introduced at an angle or obliquely through the reticules, then resting their edges on the aforesaid support structure.
This solution, which is completely valid in terms of the dismountable nature of the plaster slabs, does however present a two-sided problem. On the one hand, the profiles of the reinforcing supporting the slabs remain visible, directly and decisively affecting the appearance of the false ceiling, so restricting its use to office premises and the like; on the other, there is the fundamental fact that to fit and remove the slabs as described, they have to be inclined so that the support structure must be a considerable distance from the frame, of at least 15 cm. This leads to a major loss of space which is, indeed, far greater than that required to install piping or ducting in the gap formed by the false ceiling and which, in most cases, need not be more than 5 cm. This therefore amounts to a loss of 10 cm per ceiling which, in a building of ten levels, means that there will be an excess elevation of the building, for a predetermined ceiling height, of the order of one metre, with the resulting considerable material waste this represents.

DESCRIPTION OF THE INVENTION

The plaster slab fitting system proposed in this invention has been designed to completely resolve this problem, retaining the dismountable quality required, so that the assembly can be done at any distance from the structural frame and specifically at the maximum proximity permitted by the installations to be placed between the frame and the ceiling.
To this end, and in more specific terms, the system put forward is based on the use of plaster slabs which, on at least two edges, and specifically on two opposite edges, have small stepped grooves, preferably of cylindrical form which, when the flush slabs are side-fitted, form openings which are also cylindrical and stepped, and which are designed to provide the points at which the slabs are secured to the frame.
Threaded rods are used to secure the slabs in place: at one end, said rods have a rocker-arm or articulation enabling the rod to be fixed to the frame in a drill hole. The rod has three sets of nuts and washers, of which the top one is to secure the rocker-arm to the frame and then the rod: the second is to level the plate securing points correctly, forming a positioning stop for them during pre-assembly; and the third washer and nut set is for eventually securing the two plates between which it functions, specifically providing a stop on the step formed by the two sectors of the opening created by the complementary grooves on the two slabs which meet here.
Another of the features of the invention is that the washer in this third or bottom group, actually used to secure the plaster slabs, has fastening teeth on the side where it adapts to the slabs as the nut is tightened, to prevent the slabs from slipping sideways.
Optionally, these washers may be stretched to one degree or another rather than being circular, and they are placed transversally or longitudinally in relation to the connection between the slabs: clearly the widest part of the grooves on said slabs would be shaped and of a size so as to adapt to the shape and size of said washers.
At all events, once the plaster slabs are secured in place, the excess on the threaded rods is cut off and the small openings formed in the connecting lines between the slabs are filled with plaster until flush with the underside of the slabs, thereby completely concealing the securing devices used.

DESCRIPTION OF THE DRAWINGS

To complete this description and to aid in a better understanding of the features of the invention, these specifications are accompanied by a set of drawings, forming an integral part hereof, showing the following by way of illustration and without limitation:

Figure 1 shows a diagrammatic side elevation in cross-section of a false plaster ceiling whose slabs are secured to the frame using the assembly system which is the subject of this invention.
Figure 2 shows a considerably enlarged detail of one of the securing points in the previous figure.
Figure 3 shows a partial face view of the assembly shown in figure 1.

Figures 4 and 5, finally, each show details in a lower face view of one of the points where the slabs are secured in place, in accordance with the practical design and assembly of the bottom or securing nut washer.

A PREFERENTIAL DESIGN OF THE INVENTION

The figures show how the assembly system put forward is based on the use of plaster slabs (1) which, of any suitable size and shape, have grooves on their edges aligned with the securing points provided: each of the said grooves forms two sectors of different size, one of which (2) is a small-bore semicircle while the other (3) is larger and may also be semicircular or any other shape, as already pointed out, and as shown in turn in figures 4 and 5.
Said grooves (2-3) in the edges of the plaster slabs (1) are placed so that they are aligned, as shown in figure 3, when the planes are linked, flush: the upper and smaller diameter sector (2) forms a small cylindrical opening whose diameter enables a threaded rod (4) to be inserted, and which is the junction at which the plates (1) are linked to the frame (5) of the space where the false ceiling is to be installed: said rod (4) ends in a rocker-arm (6) which, as particularly shown in figure 1, passes through the base of the frame (5) coaxial to the threaded rod (4) then turns 90° so as to form a retaining stop, secured in place with the nut-and-washer set (7-8) which is tightened on to the bottom of the frame (5) so fixing the threaded rod (4) in place vertically and in such a way as to fit into the aligned grooves (2-3) on the laterally adjacent plaster slabs (1).
In addition, on each said threaded rod (4) there is a second nut-and-washer set (9-10) so that the washers (10) at the lower level form positioning stops for the plaster slabs (1) to ensure that the false ceiling is exactly levelled, once said nut-and-washer set (9-10) is properly arranged using suitable levelling devices, e.g. a free-hanging cord, although the most sophisticated techniques may be used for these purposes, such as laser levelling.
The assembly is finally secured with a third nut-and-washer set (11-12) which acts on the step formed by the two different-sized sectors of the grooves (2-3) so that this set (11-12) is housed in the larger sector (3) where it will eventually be concealed as shown on the left of figure 1 by filling this housing with a small amount of plaster (13) once the excess length of threaded rod (4) has been cut off.
Said bottom washer (12) can be circular as shown in figure 3, so that the sector (3) of the grooves on the plaster slabs (1) will also be semi-circular: or said washer (12) may be rectangular and considerably lengthened, as in figures 4 and 5, with sharp corners as in figure 5 or with rounded ends as in figure 4: moreover, its longer axis may be set across or along the connecting line (14) between the slabs, as also seen in figures 4 and 5. At all events, said bottom washer (12) has teeth (15) on the side resting on the slabs, to prevent unwanted sideways movement by the slabs.
An assembly system is thus attained which is simple, which can be employed by any operator, without special professional qualification, without rubble and a plaster mass: the resulting gap formed by the false ceiling is easily accessible, requiring only the removal of the filler (13) used to conceal the slab fitting metal and to form the surface continuity of the false ceiling.
It is not felt necessary to further extend this description in order for any expert in the field to grasp its scope and the benefits arising herefrom.
The materials, shape, size and arrangement of the elements may be varied provided that this does not involve an alteration to the essence of the invention.
The terms of these specifications must be taken at all times in the broad sense, without limitation.

Claims

A system for the fitting of plaster slabs, specifically for the formation of false ceilings wherein, essentially, between the edges of the plaster slabs (1) forming the false ceiling and the frame (5) to which they are to be secured, there is a number of securing points, appropriately distributed, for preference on at least two opposite sides of each slab. In line with each said securing point, said slabs incorporate a small groove on the edge, in which two sectors (2) and (3) are formed, of different diameters, and forming an intermediate step. It is a particular feature that the grooves (2-3) of one side of a plaster slab (1) are aligned with those on the adjacent slab, forming openings with the latter which have a stepped widened section at the mid-point. Said openings are intended to house a securing iron for said slabs (1) to the frame (5), in the form of a threaded rod (4) topped by a rocker arm (6) for insertion and securing on the frame (5). On said threaded rod there are three sets of nuts and washers, one at the top (7-8) which adapts to the underside of the frame (5) and to hold the threaded rod (4) in place in the vertical position, an intermediate set (9-10) forming a positioning stop for the plaster slabs (1) for their correct levelling, and a third set, at the bottom (11-12) which fits inside the bottom wider sector (3) of the grooves on the edges of the slabs, and which forms the real fixing element, on the intermediate steps in said grooves.
A system for the fitting of plaster slabs as set forth in claim 1, wherein said bottom securing washer (12) may be circular or stretched, of the size and shape for the bottom sector (3) of each groove in the slabs and, in any case, on the side adapted to said slabs, with teeth for locking onto said slabs to prevent sideways displacements between them.
A system for the fitting of plaster slabs as set forth in previous claims, wherein the housing for the nut-and-washer set (11-12) is, following the tightening of these elements and the removal of the excess part of the threaded rod (4), filled (13) with plaster flushed with the underside of the slabs (1) and concealing the securing metal.