This invention is based on a large hollow brick, this not being a limitation of sizes because the solution provided by the invention is applicable to smaller sizes or traditional sizes provided that the conditions of the cavity so allow, taking into account that the aim is to provide said hollow bricks with the option of opening up the chasings necessary for installing service conduits, pipes, tubing, cable troughs or others without damaging or unduly weakening the construction piece.

As is known, in walls, partitions, faces or the like built with ceramic materials, specifically with double cavity bricks, which is most customary and general practice in construction today, it is necessary to open up chasings in certain parts of the brick, which advisably must coincide with one of the grooves of the brick, leaving the space necessary for installing the aforementioned service conduits.

However in practice, the breaking of the brick or the opening up of the chasing has some drawbacks, such as the fact that the space of the cavity or width of the groove, resulting from its standardized 7 cm thickness, is not enough for the correct or complete housing of said installations, forcing the central rib of said brick to be broken, implying undue and highly unadvisable weakening of the brick which at this point would be joined only at the rib opposite side to the chasing.

Another drawback is that the location of the grooved part of the brick where the chasing must be made, generally in the central groove of small or large bricks, must be done by approximately calculating the area, which does not always give the right result, though the outside of bricks today indicate the horizontal intersection ribs with a section that is wider than the common ribbing of the brick.

The invention has as its purpose adapting bricks in a simple manner so as to not alter their structure and not complicate the manufacturing process, such that they adapt to the need for the chasing without weakening their structure, even facilitating locating the groove corresponding with this adaptation. Nor is it necessary to weaken the area "to be chased" because most bricks must be used with full strength, although it could be an optional or exceptional alternative.

In reference to the state of the art, the invention is carried out on common double cavity bricks with a regular format of 25 x 12 x 9 cm and also for double cavity ceramic plates such as those disclosed in K 158712-1-2 "HOLLOW BRICK", in which double cavities are alternatively arranged in a combined version of different widths in which their distribution is calculated for better performance under the working stresses of said brick according to plate measurements. Document DE 201 05 370 U1 describes a refractory or "stock" type brick having axially aligned round holes for electric installations and other alternating, scalable holes for similar functions and, as the case may be, the holes are provided with a row of flanged grooves on their sides having a smaller section, which are accessible through the side surface breaking the outer wall.

A brick according to the preamble of claim 1 is disclosed in ES-A2-2 081 737.

The invention consists of providing the brick with one or more grooves or cavities having a section with a width that is greater than the adjacent one, the latter being reduced in the same proportion by which the first one has been increased such that the central separation vertical rib between them is eccentric with respect to the central rib of the remaining symmetrical grooves of the brick.

Another detail of the invention is that the groove of the hollow brick chosen for extension is preferably the central groove. Said extension is provided so as to obtain sufficient space for the housing and passage of the installation of the service conduits once the chasing is opened up in said groove, assuring the structural reliability of the brick given that the central vertical rib or separation rib of this cavity and the adjacent one, now with a smaller section, would not be weakened by the chasing.

The invention likewise foresees providing the brick with external means for identifying from the outside the place where the chasing must be made with absolute certainty, which indication may be an arrow introduced on the lower rib of the groove pointing out the space to be chased, and even a legend engraved on the clay with an expression such as "make chasing here", or similar instructions, marking the space to be chased between said rib and the top portion of the groove prepared for being opened up with no confusion.

The chasing is opened up traditionally, leaving a continuous chasing open longitudinally throughout the bricks of the same tier which, according to the measurements of the prepared cavity, shall be enough so as to prevent the intermediate rib from breaking and completely housing the standard conduits for receiving the wall.

A broader idea of the features of the invention will be given below in reference to the sheets of drawings attached to this specification which, in a somewhat schematic manner and only by way of example, show the preferred details of the invention.

• Figure 1 shows a foreshortened perspective view of a double cavity (3) in the plate (1) from one end thereof with a groove (4) prepared for chasing.
• Figure 2 shows a view equal to the previous one from the opposite end of said plate (1).
• Figure 3 shows a front elevational view of the plate (1) with the cavity (4) for the conduits (12).
• Figure 4 shows a view similar to the previous one with the cavity (4) open (13) at the chasing (7).
• Figure 5 shows a side elevational view of said cavity (4) cut away, open at the chasing (7).
• Figure 6 shows a front elevational view with the sizes proportion of the cavities (3) and (4).

A preferred embodiment of the invention is determined by the example shown in said drawings, representing a hollow plate (1) of the ribbed type (2) and symmetrical double cavities (3) in pairs, essentially one of them being a cavity or groove (4) with a larger section or width in the same proportion by which the adjacent cavity (5) is of a lesser section or width, the vertical intersection partition (6) between the cavities (4) and (5) being proportionally eccentric with respect to the symmetrical vertical partitions (6A) of the remaining symmetrical cavities (3).

A cavity (4) for chasing is externally demarcated by the space or area (7) comprised between the longitudinal ribs (8) below and (9) above, the first one or any of the two externally provided with an engraved message (10) indicating the place where the chasing must be made, and even an inscription (11) engraved in the clay, such as "make chasing here", so as to unmistakably indicate the place where the cut for the chasing must be made.

As can be seen in Figure 4, the chasing (13) internally houses the tubing (12) for installing the conduits (14) such that said tubing (12) does not overflow the space of the surface (7), having the required size inside the cavity (4) for the purpose of preventing any alteration or projection on the outer side of the brick (1) for the corresponding treatment of the wall when the layer of mortar is spread.

Having sufficiently described the nature of the invention, it is hereby stated for all intents and purposes that said invention is not limited to the exact details of this specification, rather on the contrary, those modifications considered appropriate shall be introduced provided that they do not alter the essential features of the appended claims.