SWITCHES AND TAPS HOUSING BOX WITH COVER

Technical field

The present application for a patent concerns a box to be embedded into the wall that houses switches and current taps and which is equipped with a cover.

Background Art

As everybody knows, switches and wall-tipe taps are always assembled inside an usually molded tank, which has to be previously embedded and fastened to the wall.

These tanks are usually parallelepipedes and their sidewalls are provided with one or more sectors of reduced thickness. The sectors can be easily pierced to obtain suitable holes where the trailing section of the hoses con- taing electric cables can be passed through.

In order to appreciate the advantages of our box.it is deemed it necessary to mention the modalities of installation of switches and taps to be embedded.

First of all the wall is dug by using stone chisel and hammer, in order to obtain some cavities corresponding to the already chosen points for the dislocation for every room. Next these cavities are interconnected by executing some chases in the wall, using stone chisel and hammer or some special milling machine, called jig borer. When the above mentioned operations are finished, the installation continues with the laying of the boxes correspondent to the cavities and the hoses along the

chases; are temporarily immobilized into their respective housing by using gypsum mortar. The operation of assembling switches and taps inside boxes and of threading electric cables through hoses, are executed when all the walls have already been plastered and sometimes even white washed.

The most frequent disadvantage an electrician has to face when assembling switches and taps is that the respective housing boxes are stained and inner encrusted by the parging spray and the necessary cleaning, takes time.

At the present, bricklayers are accustomed to stuff boxes with paper in order to prevent plaster from entering inside and consolidating. Even if these paper paddings can partially stopper, they are no remedy for another incon- venience that happens mostly when plastering is executed by special plaster sprayers, instead of being carried out by hand.

In such a case, it often happens that the box is completely submersed under the superficial layer of plastering, which is automatically sprayed from the machine to the whole wall. When this inconvenience occurs, the box is no lon¬ ger visible and to find it causes a certain loss of time; the box research usually consists in knocking gently with hammer on the zone where the box is thought to be, the knocking is repeated until the wall sounds void because of the presence of paper under plaster layer instead of bricks.

Disclousure of invention

The purpose of the present invention is to make up above mentioned inconveniences. This purpose is attained thanks to the cover that our box is provided with; the cover infact pads frontally and protects the inner room of the box from the moment of the embedding up to the moment of the electrical system laying. On its internal face, the cover has two couples of flexible crooked teeth that are able to hook two metal strips with an elastic release, these strips are placed at the transversal sides of the box mouthpiece and they are meant to support the terminal board which wires will be connected to.

The foresaid cover can be easily removed by exerting a traction strong enough to spread teeth elastically.

Moreover, the cover is inside the mouthpiece and lined up it; the box is embedded into the wall so that its edges protrude for a tract as long as the thickness of the layer of plaster the wall is to be covered with. Once the wall has been plastered, the cover will be perfectly coplanar to the plaster surface and it will run no risk of being submersed and becoming invisible because of the plaster sprayed by the spraying machine.

Brief description of drawings

From now on the description of our invention refers to the included drawings that have illustrative value:

- fig. 1 shows an axonometric representation of the box with the ^" cover lifted;

- fig. 2 is a cross section of the box with a transversal

plane passing by one of the crookd teeth couple;

- fig. 3 is a cross section of the box with the longitudinal midplane.

Making reference to these figures, the model consists of an open box (1); substantially it has the shape of a parallelepiped with the four sides slightly slanting towards the external. The box is a plastic molded enbloc. A metal insert (2) is applied at the centre of the shortest opposed sides (la). The insert consists of a brass lamination, bent so that it shows a profile resembling an upside-down "L". In this way its horizontal wing (2a) is placed at the box mouthpiece (1), turned towards the internal.

The cover (3) consists of a rectangular, plastic molded plate, whose dimensions exactly fit the internal of the box mouthpiece (1).

At the centre of the short sides of this cover two couples of crooked teeth are obtained, while molding-, said teeth overhang from the internal face in order to be able to hook the wings below (2a). Both wings are provided with a central hole (2) where the . clamping screw of the terminal board to the box is to be screwed. The clasping of the cover to the wings is obtained by a simple pressure and likewise the relative unhooking can be determined by forcing, with the help of a screw- driver passed trough one of the slots (3a). These slots are purposely obtained transversally on the cover (3) at the centre of each couple of teeth (4).

As illustrated in fig. 2 and fig.3, the cover (3)

has such dimensions as to fit exactly the box mouthpiece, once the cover has been hooked to the metal insert (2). The mouthpiece is equipped with an external flange (lb).

The flange will remain submersed under the plaster layer, whose outer surface will line up the sides of the said mouthpiece.