TILE LEVELLING DEVICE

Abstract

 A tile levelling device (10) configured for the mutual levelling of two or more tiles (P) already laid on a fresh or not fully hardened glue, wherein a joint is defined between the at least two adjacent laying tiles, wherein the device comprises:
- a monolithic tie rod (20) comprising:
at least one transverse element (21) elongated along at least one longitudinal axis and defining a rest plane for at least two adjacent laying tiles;
at least one longitudinal stem (22) protruding from the transverse element (21) with a central axis squared with the rest plane of the transverse element (21) and having a first end (221) joined to the transverse element (21), wherein a maximum width of the transverse element (21) is equal to or lower than a width of the joint defined between the at least two adjacent laying tiles and the stem (22) has a height greater than the maximum thickness of the adjacent laying tiles to be levelled, wherein the stem (22) has a transverse overall dimension equal to or less than the width of said joint; and
at least one abutment body (23) joined to a second end (222) of the longitudinal stem;
the device (10) further comprising:
- a presser (30) adapted to cooperate with the abutment body (23) of the tie rod (20) and configured to exert pressure on the side-by-side tiles.

Description

TECHNICAL FIELD

[0001] The present invention relates to a tile levelling (spacer) device, preferably an auxiliary (spacer and) levelling device for the mutual levelling of two or more tiles already laid on not fully hardened glue, wherein a joint, i.e. a space to be filled with a filling plaster, is defined between the at least two adjacent laying tiles (i.e. laid on the glue placed on the surface to be coated).

PRIOR ART

[0002] As known, the laying of tiles on a surface to be coated provides a series of passages, including spreading a glue on the surface to be coated, laying the tiles on top of it so that they are equally-distant from each other (defining a joint of a constant width between adjacent tiles) and as coplanar and levelled as possible, i.e. with the visible (or upper) surface coplanar and levelled.

[0003] In order to achieve the objective of having even and constant joint widths and a high degree of levelling, the use of levelling spacers of various types, e.g. "screw" or "wedge" or "ratchet" spacers, is known.

[0004] These known-type levelling devices are provided with a wide rest base and a separating element rising from the base.

[0005] The base must be fitted under the tiles so that the separating element slips into the joint between them and holds them at the desired distance (equal to the thickness of the separating element) and a presser element cooperates with the upper portion of the separating element emerging above the tiles to level them.

[0006] The use of such levelling spacers provides that they must be placed on the glue while the tiles are being laid on the glue itself (or immediately before). In detail, it is provided to insert the base underneath a tile already laid on the glue before the additional adjacent tile is laid and then the additional tile is placed adjacent to the first tile on top of the free base portion.

[0007] Once the presser element has been actuated and the glue has hardened, the separating element (and the presser element) is removed, triggering a fracture of the separating element (or a prevailing portion thereof) relative to the base.

[0008] It has been observed, however, that sometimes some levelling devices fail to meet their purpose, e.g. they break before the tiles have been levelled (and the glue has not yet fully hardened).

[0009] In such circumstances, the tiler must remove the already laid tile, clean and re-lay the glue on the surface to be coated (and on the tile laying surface) and repeat the laying operations with a new levelling spacing device.

[0010] Another typical case is that of realising that, after the levelling spacer devices have been applied, the tiles have been laid and the levelling spacer devices have been actuated, small differences in height, so-called "teeth", remain between the tiles. This mainly occurs in case the laid tiles have flatness defects. Also in this circumstance, the tiler, in order to remedy, must remove the uneven tile and apply additional levelling spacer devices in the area where the tooth was created.

[0011] A further existing technique is the use of levelling devices that are completely "recoverable", they are applied with already laid tiles and with glue that is still fresh. Their use depends on the fact that the levelling device must be removed when the glue has not completely hardened but has nevertheless set on the tiles in order to hold them in place. Each individual recoverable levelling device must therefore be removed manually before the glue has fully hardened. During the removal of the "recoverable" levelling device, glue residues then appear in the joint, which will have to be removed before grouting, and more glue must then be removed from the recovered levelling device before it can be used again. Furthermore, the step of inserting into the joint and removing from the joint the levelling device involves the risk of chipping the tile border, e.g. in surface-glazed tiles.

DISCLOSURE OF THE INVENTION

[0012] An object of the present invention is to overcome the mentioned drawbacks of the prior art, within the context of a simple, rational and cost-effective solution.

[0013] In particular, an object of the present invention is to make it possible to level (and equally-space) two (or more) adjacent tiles after these tiles have already been laid on the glue (not yet fully hardened or, better said, "fresh" glue).

[0014] A fresh or not fully hardened glue is understood herein to be a glue in a fluid (pasty) or liquid/semi-liquid state that can be spread (setting) on a surface to be coated, e.g. with the manual mechanical action of a trowel, and/or in the first few minutes of its application. Within the scope of this object, the present invention is such as to allow the use of a levelling (auxiliary) spacer device adapted to allow the levelling (and spacing) of two adjacent tiles already laid on the glue (not yet fully hardened or "fresh") by correcting and/or compensating for the possible failure of a (conventional) levelling spacer device and/or by correcting an area that was not properly levelled from the beginning.

[0015] A further object is to make this correction operation possible safely, robustly, easily and quickly for the tiler, as well as without damaging the tiles, allowing the tiler to act promptly and effectively without having to remove the tiles already laid or interfere with the rest of the work already done.

[0016] Furthermore, an object of the present invention is to enable the tiler to achieve the aforementioned objects with a device that is entirely similar, e.g. in terms of type and method of removal (after the object has been performed and the glue has fully hardened), to other "traditional" levelling devices used for laying the (same) floor and/or the (same) wall tiles, e.g. without damaging the laid tiles.

[0017] These objects are achieved by the features of the invention set forth in the independent claim. The dependent claims outline preferred and/or particularly advantageous aspects of the invention.

[0018] The invention, in particular, makes available a tile levelling (spacer) device (preferably or predominantly for use in the mutual levelling of two or more tiles already laid on a glue that is not fully hardened or "fresh"), in which a joint is defined between at least two adjacent tiles being laid, wherein the device comprises:

• a monolithic tie rod (made of a plastic material) comprising:

  at least one transverse element elongated along at least one longitudinal axis and defining a rest plane for at least two adjacent laying tiles;

  at least one longitudinal (non-threaded) stem protruding from the transverse element with a central axis squared with the rest plane of the transverse element and having a first end joined to the transverse element, wherein a maximum width of the transverse element is equal to or less than a (minimum) width of the joint defined between the at least two adjacent laying tiles and the stem has a height greater than the maximum thickness of the adjacent laying tiles to be levelled, wherein the stem has a transverse overall dimension equal to or less than the width of said joint, preferably (but without limitation) contained within the width of the transverse element; and

  at least one abutment body joined to a second end of the longitudinal stem;

  the device further comprising:

  • a presser (made of a plastic material) adapted to cooperate with the abutment body of the tie rod and configured to exert pressure on the side-by-side tiles.

[0019] Thanks to this solution, the transverse element can be inserted into the joint between already laid tiles and pushed to a lower height than the (lower) laying surface of the adjacent tiles (within the glue). At this point, the device can be rotated, e.g. by 90°or at least 45°, thus bringing the rest surface portions (opposite to the stem) of the transverse element below a respective tile of the two or more adjacent tiles and, by means of the action of the presser, levelling them off (while keeping them at the correct distance from each other by means of the stem).

[0020] As is clear, this advantage is even more relevant when the use of such a levelling (auxiliary) spacer device occurs after the adjacent tiles to be levelled have already been laid on the glue, e.g. when a "traditional" levelling device has failed its purpose and/or cannot be used.

[0021] An aspect of the invention could provide that the first end of the stem is joined to the transverse element in a frangible manner, preferably by forming with it an edge (internal, preferably 90° or substantially sharp, with a connection radius lower than 1 mm , i.e. between 0 and 1 mm, wherein the edge, for example, extends for the entire perimeter of the first end of the stem or for one or more sections of the perimeter of the first end of the stem with a lower extension than the entire perimeter of the stem) which acts as a fracture trigger line at the stem-transverse element interface (fracture that propagates throughout the thickness of the stem separating the entire stem from the transverse element).

[0022] Further, the stem may have a constant cross-section for the entire height thereof (without cross-section restrictions), wherein, for example, the cross-section of the stem is constant or unrestricted for an axial section of the stem from its first end, wherein it joins the transverse element, to a height at least equal to the height of the (maximum) visible surface of the tiles it is intended to level or for a prevailing section of the stem - i.e. greater than half of its overall length - which includes (and starts at) its first end joining the transverse element.

[0023] Advantageously, the stem may have any cross-section, whether circular, polygonal or having an elongated shape, preferably elliptical, wherein a major diameter is orthogonal to the longitudinal axis of the transverse element (and a minor diameter is parallel to the longitudinal axis of the transverse element).

[0024] Further, the stem may have a predetermined torsional elasticity (defining a torsion bar), so as to allow a rotation of the transverse element joined to the first end of the stem, around the longitudinal axis of the stem, of at least 90° (preferably between 90° and 180°) with respect to the second end, starting from an unperturbed starting position, without plastic yielding of the stem, and the elastic return of the transverse element to the starting position (wherein preferably the torsional elastic rigidity of the stem, i.e. the torque defined by the elastic response of the stem, is configured so as to allow a rotation of the transverse element immersed in a viscous fluid - such as the fresh or not yet fully hardened glue - so as to be able to move the glue insisting on the side of the transverse element). According to an embodiment of the invention, the abutment body may comprise a threaded pin provided with a thread having a parallel screwing axis coinciding with the central axis of the stem and the presser may comprise a knob provided with a screw nut that can be screwed on the threaded pin.

[0025] In such an embodiment, the tie rod may comprise a (prismatic) handle element protruding from the abutment body (i.e. placed at the free end of the threaded pin) and configured to be able to rotate - manually - the tie rod (and with it the transverse element) around the central axis of the stem. The handle element is also configured to be gripped with the fingers to rotate the tie rod and, for example, to be held in place after rotation within the joint, during actuation (screwing or sliding) of the presser.

[0026] Advantageously, the handle element may have a maximum width that is less than the diameter (of the bottom of the thread) of the threaded pin, this allows the presser to be inserted from above (as will better appear later) once the tie rod is fitted into the joint.

[0027] In addition, the stem may have a smaller transverse dimension than the diameter (of the bottom of the thread) of the threaded pin.

[0028] According to a further embodiment of the invention, the abutment body may comprise a serrated strap and the presser may comprise a (sliding) knob provided with at least one tooth configured to engage the serrated strap in a pop-up manner.

[0029] Also in this case - although not strictly necessary - it is possible to provide that the tie rod may comprise a (prismatic) handle element protruding from the abutment body (i.e. placed at the free end of the serrated strap), for example defined by a non-serrated section of the same serrated strap, and configured to be able to rotate - manually - the tie rod (and with it the transverse element) around the central axis of the stem.

[0030] According to a further embodiment of the invention, the presser may comprise a wedge and the tie rod may comprise a pair of stems spaced apart from each other by a through opening adapted to be at least partially crossed by the wedge and delimited at the top by a crosspiece joining the second end of the stems, wherein the first end of each stem is joined to a respective transverse element (separated from each other), wherein the longitudinal axis of each transverse element is orthogonal to a longitudinal axis of the crosspiece, each stem preferably having a predetermined torsional elasticity (defining as such a torsion bar), so as to allow a rotation of the respective transverse element joined to the first end of the stem, around the longitudinal axis of the same stem, of at least 90° (preferably between 90° and 180°) with respect to the second end, starting from an unperturbed starting position, without plastic yielding of the rod, and the elastic return of the transverse element to the starting position.

[0031] According to an advantageous aspect of the invention, the tie rod - in general - can be made of a (single) plastic material, preferably with an inorganic reinforcing filler (where preferably the inorganic filler is glass).

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Further features and advantages of the invention will be more apparent after reading the following description provided by way of a non-limiting example, with the aid of the figures illustrated in the accompanying tables.

Figure 1 is an axonometric view of a first embodiment of a levelling spacer device according to the invention.

Figure 2 is a front view of a tie rod of the first embodiment of the device in Figure 1.

Figure 3 is a side view of Figure 2.

Figure 4 is a sectional view along the trace of section IV-IV of Figure 2.

Figure 5 is a sectional view along the trace of section V-V of Figure 2.

Figure 6 is an axonometric view of a first step of a working sequence of the device of Figure 1.

Figure 7 is a side (partially sectioned) view of Figure 6.

Figure 8 is an axonometric view of a second step of the working sequence of the device of Figure 1.

Figure 9 is a side (partially sectioned) view of Figure 8.

Figure 10 is an axonometric view of a third step of the working sequence of the device of Figure 1.

Figure 11 is a side (partially sectioned) view of Figure 10.

Figure 12 is an axonometric view of a fourth step of the working sequence of the device of Figure 1.

Figure 13 is a side (partially sectioned) view of Figure 12.

Figure 14 is an axonometric view of a fifth step of the working sequence of the device of Figure 1.

Figure 15 is a side (partially sectioned) view of Figure 14.

Figure 16 is an axonometric view of a sixth (and final) step of the working sequence of the device of Figure 1.

Figure 17 is an axonometric view of a second embodiment of a levelling spacer device, according to the invention.

Figure 18 is a front view of a tie rod of the second embodiment of Figure 17.

Figure 19 is a side view of Figure 18.

Figure 20 is a plan view (from above) of Figure 18.

Figure 21 is an axonometric view of a first step of a working sequence of the device of Figure 17.

Figure 22 is an axonometric view of a second step of a working sequence of the device of Figure 17.

Figure 23 is an axonometric view of a third step of a working sequence of the device of Figure 17.

Figure 24 is an axonometric view of a fourth and fifth step of a working sequence of the device of Figure 17.

Figure 25 is an axonometric view of a third embodiment of a levelling spacer device, according to the invention.

Figure 26 is a front view of a tie rod from the third embodiment of the device of Figure 25.

Figure 27 is a side view of Figure 26.

Figure 28 is an axonometric view of a first step of a working sequence of the device of Figure 25.

Figure 29 is an axonometric view of a second step of a working sequence of the device of Figure 25.

Figure 30 is an axonometric view of a third step of a working sequence of the device of Figure 25.

Figure 31 is an axonometric view of a possible "four-lobed" embodiment of a tie rod of the device according to the first embodiment.

Figure 32 is an axonometric view of a further possible "tri-lobed" embodiment of a tie rod of the device according to the first embodiment.

BEST MODE TO IMPLEMENT THE INVENTION

[0033] With particular reference to these figures, 10 globally denotes a (spacer and) levelling device cooperating in the laying of slab-shaped products, hereinafter referred to generically as tiles P (without thereby excluding the possibility of using it for the laying of slabs in general, for example of natural stone or other material, for coating surfaces, i.e. floorings, walls, ceilings and the like), on an glue, wherein the device 10 is, in particular, configured for the mutual levelling of two or more tiles already laid on glue that has not fully hardened (i.e. still in a fluid/pasty state).

[0034] The device 10, for example, is preferably intended as an auxiliary device to be used, as necessary, in combination with (or as a partial replacement for) levelling spacers (having a wide tile rest base) of a known type, e.g. when one or more of these fails to meet its purpose (or breaks prematurely) and the adjoining tiles P are already laid on the glue. Each tile P, adapted to be laid to coat a surface (masonry), has a wide laying surface P2, for example lower, and an opposite wide visible surface P1, for example upper, preferably of homologous shape (for example polygonal, preferably quadrangular) with respect to the laying surface P2.

[0035] Each tile P then comprises a plurality of lateral sides P3, generally squared with the laying surface P2 and the visible surface P1, which laterally delimit the tile itself.

[0036] Two or more tiles P are placed as mutually resting (and partially gripped) on an glue, in a fluid/pasty state, which has been previously spread on the surface to be coated with the tiles P.

[0037] In detail, between two adjoining tiles P, a so-called joint is defined, i.e. a separating interspace, delimited by two lateral sides P3, for example parallel, of the two adjoining tiles. Traditionally, the joint has a width substantially of 0.5 mm, 1 mm, 1.5 mm, 2 mm, 3 mm, 4.8 mm or more (for tiles having thicknesses ranging from a few mm to about 20 mm or more).

[0038] The device 10 comprises (or consists of) a tie rod 20, also known as a "baseplate", and a presser 30 (made in a separate body from the tie rod 20).

[0039] The tie rod 20 is configured to level (and keep spaced) two side-by-side tiles P (already laid on "fresh" or not fully hardened glue) and spaced by a joint, following a suitable levelling action exerted by the presser 30, as will be better described below.

[0040] The presser 30 is configured to co-operate with the tie rod 20, as will be described, and exert pressure on the visible surfaces P1 of the side-by-side tiles P, in order to level them. Preferably, the tie rod 20 is defined by a monolithic body, i.e. made of a single piece (mono-material or multi-material).

[0041] The tie-rod 20 comprises at least one transverse element 21, e.g. elongated along at least one longitudinal (straight) axis.

[0042] The transverse element 21 is configured to be fitted (with the short side) inside the (predefined) joint between two side-by-side tiles P (and laid on the still "fresh" or not completely hardened glue) and, when it is at a level lower than the laying surface P2 of (both) tiles P - following a rotation imposed thereon - to position itself at the back of the laying surface P2 of (both) tiles P, for example so that the tiles P are superimposed (in plan view) on the transverse element 21 itself.

[0043] In any case, the transverse element 21 comprises a lower surface 210, for example plane or "V"-shaped, adapted to be arranged distal from the laying surface P2 of the tiles P in operation (i.e., when it is fitted in the joint below the level of the tiles P), and an opposite upper surface 211, for example continuously plane or defining reliefs that are coplanar to each other, adapted to be arranged proximal to the laying surface P2 of the tiles P and, for example, in contact therewith.

[0044] The upper surface 211 of the transverse element 21 (or at least a portion thereof) is in practice intended to support a portion of the laying surface P2 of these two tiles P (placed side-by-side to and spaced apart from each other by a pre-formed joint).

[0045] In practice, the upper surface 211 (in its entirety or at least a portion thereof, e.g. the top of two or more separate reliefs) defines a rest plane for at least two adjacent (and separated by a pre-formed joint) laying tiles P.

[0046] The transverse element 21 is adapted to be immersed in (the layer of) glue placed on a screed that is (already) coated by the tiles P defining the aforesaid joint, with the lower surface 210 facing the screed itself and the upper surface 211 facing the overlying tiles P.

[0047] The transverse element 21 has - preferably - an elongated shape (along a longitudinal axis) and has two opposite axial ends.

[0048] Furthermore, the transverse element 21 comprises two opposite lateral sides 212 that are, for example, parallel to each other and squared with the aforementioned rest plane defined by the upper surface 211.

[0049] For example, the (maximum) thickness of the transverse element 21 is given by the (maximum) distance between the upper surface 211 and the lower surface 210; the (maximum) width of the transverse element 21 is given by the (maximum) distance between the two sides 212; and the (maximum) length of the transverse element 21 is given by the (maximum) distance between the two axial ends thereof (and is greater than the width and height thereof).

[0050] Preferably, the (maximum) width of the transverse element 21 is equal to or (slightly) lower than the (minimum) width of the joint defined between at least two adjacent laying tiles (i.e. already laid on the glue), so that the transverse element 21 can be fitted into the joint (with a small clearance) with its longitudinal axis parallel to the direction of the joint (and the lower surface 210 facing the screed).

[0051] In detail, the (maximum) width of the transverse element 21 can be substantially of 0.5 mm, 1 mm, 1.5 mm, 2 mm, 3 mm and 4.8 mm or greater, preferably substantially of 1.5 mm (for insertion in joints greater than or equal to 1.5 mm, which are those in which statistically the greatest number of cases of failure of traditional levelling spacers is observed).

[0052] The transverse element 21, preferably but not limitedly, has a shape that is symmetrical to a central (or median) plane orthogonal to the rest plane defined by the upper surface 211 and the longitudinal axis of the transverse element 21.

[0053] Preferably, the transverse element 21 has a bi-lobed shape, wherein, for example, each lobe is symmetrical to the other with respect to the aforesaid median plane orthogonal to the rest plane and the longitudinal axis of the transverse element 21.

[0054] Each lobe is joined to the other at a central area of the transverse element 21 and ends at a respective free axial end of the transverse element.

[0055] Preferably, the transverse element 21 is symmetrical to both the median planes orthogonal to each other and orthogonal to the rest plane defined by the transverse element 21. The transverse element 21 can have, for example, a thickness at the central plane (with symmetry orthogonal to the longitudinal axis thereof) which is greater than a thickness thereof at the axial (opposite) ends and, for example is decreasing from the central plane towards the ends.

[0056] In practice, such a thickness gradient of the transverse element 21 facilitates the insertion of the transverse element 21 into the joint and/or the glue and the rotation of the transverse element itself within the glue (not yet fully hardened or "fresh") below the laying surface P2 of the tiles P when they are already resting on the glue layer.

[0057] The tie-rod 20 further comprises a longitudinal stem 22 protruding from the transverse element 21 (i.e. from its upper surface 211) with a longitudinal centre axis squared with the rest plane defined by the upper surface 211 of the transverse element itself.

[0058] The stem 22 is configured to define a separating element, which is adapted, in use, to be fitted (and interposed) between facing lateral sides P3 of said adjoining tiles P (and placed side by side along a flanking direction) and, eventually, to contact them (and/or to define an abutment for them) by defining/maintaining the joint width between the adjoining tiles P.

[0059] The stem 22 has a first (lower) end 221 bound (and joined) to the transverse element 21 and an opposite second (upper) end 222.

[0060] In practice, the stem 22 develops longitudinally from the first end 221 to the second end 222.

[0061] The first end 221 is joined (joins) to the transverse element 21, i.e. to the upper surface 211 thereof, for example to a central area of the transverse element 21 (i.e. of its upper surface 211) which subdivides the transverse element 21 into two lobes (opposite to the stem itself).

[0062] Preferably, but not limitedly, the stem 22 (i.e. its first end 221) is centred on the transverse element 21, i.e. its central axis belongs to the median plane orthogonal to the rest plane and to the longitudinal axis of the transverse element 21, even more preferably it coincides with the intersection of the median planes of the transverse element 21 orthogonal to the rest plane.

[0063] It is not excluded, however, that the stem 22 may be (slightly) off-centred with respect to the transverse element 21, i.e. its central axis may be parallel and eccentric with respect to the intersection of the median planes of the transverse element 21 orthogonal to the rest plane.

[0064] The first end 221 is, preferably, (substantially) coplanar to the upper surface 211 of the transverse element 21, i.e., to the rest plane defined by it.

[0065] The first end 221 preferably joins to the transverse element 21, i.e. to its upper surface 211, in a frangible manner, preferably forming with it an edge configured to act as a (brittle) fracture trigger line at the stem-transverse element interface.

[0066] In practice, the edge is configured to allow and trigger a (brittle) fracture of the (entire) stem 22 with respect to the transverse element 21, when (the transverse element 21 is bound in the hardened glue and) an (impulsive) tensile and/or bending and/or torsional force is applied to the stem 22.

[0067] The aforementioned (inner) edge is, for example, substantially sharp, i.e. between the outer surface (one or more directrixes of the same) of the stem 22 and the upper surface 211 of the transverse element 21 an angle is formed preferably of 90° and/or with a connection radius lower than 1 mm, i.e. between 0 mm and 1 mm.

[0068] Advantageously, once the fracture of the stem 22 with respect to the transverse element 21 is triggered at the first end 221 of the stem 22 (starting from the aforementioned edge), the (brittle) fracture propagates throughout the thickness of the stem 22 (at the first end itself) separating the entire stem 22 from the transverse element 21.

[0069] The stem 22 preferably has a cross-section (defined orthogonally to its central axis, i.e. parallel to the rest plane defined by the transverse element 21) which is constant for its entire height (without sectional restrictions or points of lightening), wherein, for example, the cross-section of the stem 22 is constant or without sectional restrictions or points of lightening for an axial section of the stem 22 running/starting from the first end 221, wherein it joins the transverse element 21, up to an elevation at least equal to the elevation of the (maximum) visible surface P1 of the tiles P which it is intended to level or, in any case, for a prevailing section of the stem 22 - i.e. greater than half of its overall length - which includes (and starts from) its first end 221 joining the transverse element 21.

[0070] In other words, the minimum section of the stem 22 substantially coincides with the section/area of its first end 221 (minus the aforesaid connection radius).

[0071] The stem 22 can have a (any) cross-section of any shape.

[0072] In the example, the stem 22 has a (any) cross-section with a substantially circular shape, e.g. perfectly circular, or as shown, elliptical (or having a small ellipticity, e.g. of 0.2 mm). In such a case, the stem 20 is substantially cylindrical (with a circular or elliptical base), fully developed, with its base anchored to the upper surface 211 of the transverse element 21.

[0073] In such an illustrated configuration, the (any) cross-section of the stem 22 has an elongated, preferably elliptical shape, wherein a major diameter is orthogonal to the longitudinal axis of the transverse element 21 and a lower diameter is parallel to the longitudinal axis of the transverse element 21.

[0074] This maximises the strength of the stem 22 (with the same dimension across the width of the transverse element 21 and purpose, i.e. maximising the rest surface with the lateral sidewalls P3 of the tiles P).

[0075] It is not excluded, however, that the stem 22 may have a (any) cross-section of a substantially polygonal shape, such as square, rectangular (i.e. elongated and arranged - e.g. like the elliptical shape described above), rhomboidal or other, or any other shape (pentagonal, hexagonal, etc., depending on construction requirements).

[0076] In such a case, the stem 22 is substantially a parallelepiped (with a polygonal base), fully developed, with its base anchored to the upper surface 211 of the transverse element 21. In any case, the stem 22 has substantially smooth outer surfaces (not serrated, not threaded or not engrailed).

[0077] The stem 22, i.e. its axial section starting from the first end 221 and having a constant cross-section, has a transverse dimension which (like the transverse element 21) is equal to or smaller than the minimum width of the joint within which it is intended to be fitted and, preferably, is contained within the width of the transverse element 21 (i.e. is lower than or equal to that width). In practice, the first end 221 of the stem 22 is inscribed within the upper surface 211 of the transverse element 21, i.e. laterally between the two sidewalls 212 (and does not protrude from it/them).

[0078] Preferably, but not limitedly, the first end 221 of the stem 22 is tangent to the border edge defined between the upper surface 211 and each sidewall 212 of the transverse element 21 (at the largest diameter of the elliptical cross section of the stem).

[0079] Thus, the edge (which triggers the fracture of the stem 22 with respect to the transverse element 21) between the stem 22, at its first end 221, and the upper surface 211 of the transverse element 21, extends for example along the entire perimeter of the first end 221 of the stem 22 or (as in the case shown) along one or more sections (in the example, two in number) of the perimeter of the first end 221 of the stem 22 with an extension lower than the entire perimeter thereof (in practice excluding the two points/arcs of tangency between the first end 221 and the border edge of the upper surface 211).

[0080] It is not excluded, however, that the transverse dimension of the stem 22 may be greater than the width of the transverse element 21 (while remaining equal to or lower than the minimum width of the joint within which it is to be fitted).

[0081] Preferably, the stem 22 - as a whole - has a height greater than the maximum thickness of the adjacent laying tiles P to be levelled (and thus intended to rest on the rest plane defined by the upper surface 211 of the transverse element 21).

[0082] For example, the height of the stem 22 is greater than (or not lower than) the length of the transverse element 21.

[0083] Preferably, the height of the stem 22 is greater than 15 mm, preferably between 15 mm and 20 mm (even more preferably equal to 20 ± 1 mm), e.g. for the use of tiles P with a thickness lower than 20 mm, and/or equal to or greater than 30 ± 1 mm, e.g. for the use of tiles P with a thickness lower than 30 mm or 35 mm thick).

[0084] Further, the stem 22, preferably but not limitedly, may have a predetermined torsional elasticity (actually defining a torsion bar itself).

[0085] In practice, the stem 22 (elastically twisting around its own central axis) is configured to allow a rotation of the transverse element 21 joined to the first end 221 of the stem 22, around the central axis of the stem itself, of at least 90° (preferably of an arc between 90° and 180°) with respect to the second end 222, starting from an unperturbed starting position, without plastic yielding of the stem 22, and - furthermore - to allow the elastic return of the transverse element 21 to the unperturbed starting position.

[0086] Preferably, the torsional elastic rigidity of the stem 22, i.e. the torque defined by the elastic response of the stem 22 (upon release of the perturbation), is configured in such a way as to allow a rotation of the transverse element 21 immersed in a viscous fluid equivalent to the tile-laying glue while still fresh - i.e. in the first minutes after the application (by trowel) thereof on the (wall) surface to be coated with the tiles - , so as to be able to move the not yet hardened or fresh glue insisting on the sidewall 212 (at the front in the direction of rotation back towards the starting position) of the transverse element 21.

[0087] The tie rod 20 further comprises an abutment body 23 joined to a second end 222 of the rod 22, the function of which is to interact with the presser 30 to transfer a pulling action on the transverse element 21 by means of the stem 22.

[0088] In practice, the presser member 30 cooperates with the abutment body 23 of the tie rod 20 and is configured to exert a pressure on the visible surface P1 of the side-by-side tiles P as opposed to a counter-pressure exerted by the transverse element 21 on the laying surface P2 of the same tiles P.

[0089] In practice, the tiles P are levelled by the device 10 being compressed between the presser 30, which acts on the abutment body 23 of the tie rod 20, and the transverse element 21.

[0090] The abutment body 23 has a lower end joined to the second end 222 of the stem 22 and an opposite free upper end.

[0091] The abutment body 23 is made in a single (monolithic) body with (the tie rod 20, i.e. with) the stem 22 (and the transverse element 21).

[0092] For example, the tie rod 20, as a whole, is made of a (single) plastic material, e.g. obtained by injection moulding.

[0093] Preferably, the plastic material of which the tie rod 200 is made is a composite material, preferably comprising a plastic matrix and an inorganic (dispersed) reinforcing filler (where preferably the inorganic filler is made of glass).

[0094] Three embodiments of the invention are described below, which substantially differ (exclusively) from each other only in the type/shape/mode of operation of the abutment body 23 and presser 30.

[0095] In a preferred embodiment shown in Figures 1-16, the device 10 is of the "screw" type.

[0096] In such a first embodiment, the abutment body 23 comprises (or consists of) a threaded pin 231 provided with a thread (i.e. a male thread, e.g. defined by a continuous helix, preferably with a plurality of turns) having a screwing axis parallel to and coincident with the central axis of the stem 22, i.e. orthogonal to the rest plane defined by the upper surface 211 of the transverse element 21.

[0097] The threaded pin 231 axially extends (the second end 222 of) the stem 22.

[0098] In practice, the threaded pin 231 has a lower end joined (directly or indirectly) to the second end 222 of the stem 22 and an opposite free upper end.

[0099] For example, the threaded pin 231 has an axial length equal to or greater than (preferably greater, e.g. substantially double) the axial length of the stem 22.

[0100] The thread of the threaded pin 231 extends, for example, substantially over a prevailing section (or substantially over the entire length) of the threaded pin 231 and, for example, has a constant pitch.

[0101] Preferably, the diameter (of the bottom of the thread) of the threaded pin 231 is larger than the transverse dimension (diameter or larger diameter) of the stem 22.

[0102] In such a case, the lower end of the threaded pin 231 is joined to the second end 222 of the stem 22 by means of a connection section 2310, e.g. (inverted) truncated-cone, which acts as a reinforcement.

[0103] Furthermore, in such a first embodiment, the tie rod 20 preferably comprises a handle element 24 protruding from the abutment body 23, i.e. protruding from the free upper end of the threaded pin 231, which is configured to be gripped (with two fingers of one hand) to rotate - manually - the tie rod 20 (and with it the transverse element 21) about the central axis of the stem 22.

[0104] The handle element 24 is substantially prismatic in shape, for example it is defined by a parallelepiped, in the example with a rectangular base (or any polygonal shape), having a lower end joined (directly) to the upper end of the threaded pin 231 and a free upper end.

[0105] The handle element 24 advantageously has a maximum width that is smaller than the diameter (of the thread bottom) of the threaded pin 231, i.e. its axial projection is inscribed in the diameter (of the thread bottom) of the threaded pin 231.

[0106] The handle element 24 has a height substantially equal to or greater than (or at least comparable to) the length of a phalanx of a finger of a hand.

[0107] In addition, in this first embodiment, the presser 30 includes a knob 31 provided with a screw nut 310 that can be screwed onto the threaded pin 231 of the tie rod 20.

[0108] The knob 31 has an overall cup or inverted cup shape, i.e. a concave shape (with concavity facing the tiles P in operation).

[0109] The knob 31 develops, for example, around a central (revolution) axis, adapted to be placed coaxial with the threaded stem 231 when the presser 30 is screwed onto it, as will be better described below.

[0110] The knob 31 has, in the example, a substantially truncated-cone or dome shape, that is, it has an enlarged (lower) end and an opposite tapered top end.

[0111] It is not excluded that the knob 31 may have any other shape, such as for example cylindrical, like a butterfly, a handle, or other suitable shape suitable for being gripped by a hand of a person in charge of the installation for screwing it.

[0112] In the example, the enlarged (lower) end of the knob 31 defines an inlet mouth or cavity, for example substantially circular (coaxial with the central axis of the knob).

[0113] The inlet cavity has, for example, an inner diameter greater than the outer diameter of the thread of the threaded pin 231, so that the latter can be axially fitted with abundant radial clearance into the inlet cavity of the knob 31.

[0114] In the example shown, the knob 31 comprises a substantially smooth inner shell and a shaped outer shell.

[0115] The outer shell of the knob 31, for example, comprises reliefs (or ridges), for example in number of 4, to facilitate the gripping and actuation in rotation for screwing the knob itself. Each relief has, for example, a substantially triangular shape.

[0116] Furthermore, the knob 31 can have one or more windows, for example through or transparent windows, made at the wall which joins the enlarged (lower) end of the knob 31 with its tapered top.

[0117] For example, each window is made at an interspace (or recess) between two adjacent reliefs.

[0118] The knob 31, moreover, has a planar end adapted to be turned towards the transverse element 21 (parallel to the rest plane defined by it) when the presser 30 is screwed onto the threaded pin 231 and perpendicular to the central axis of the knob 31.

[0119] The planar end actually delimits (with full development) the inlet cavity of the knob 31. The planar end is for example substantially shaped like a circular crown, preferably defined by the base of a cylindrical shank coaxial with the central axis and deriving at the bottom from the (truncated-cone) cap portion of the knob 31.

[0120] In practice, the planar end is adapted to be turned in use towards the transverse element 21 (or towards the tiles P resting thereon) and defines a perfectly planar annular surface perpendicular to the central axis of the knob 31 (and parallel to the rest plane).

[0121] The knob 31 may comprise, for example at or near the planar end, an annular step protruding radially towards the outside of the knob, for example of the external shell thereof and (also) of the reliefs.

[0122] The annular step, for example, has a substantially circular shape (at least its outer perimeter) and is coaxial with the central axis (and with the inlet cavity).

[0123] As mentioned, the screw nut 310 (female thread) of the knob 31 is configured to couple (with a helical coupling) with the thread of threaded pin 231.

[0124] The screw nut 310 has, for example, a screwing axis coinciding with the central axis of the knob 31.

[0125] The screw nut 310 is, for example, made at (or near) the tapered top of the knob 31. For example, the screw nut 310 is defined at an upper shank which projects from the top of the knob 31, for example having a substantially truncated-cone (or cylindrical or prismatic) shape.

[0126] The screw nut 310 passes axially from side to side that upper shank and, for example, at its internal end (i.e. the one that opens up into the internal shell of the knob 31) is provided with a lead-in taper to facilitate the axial insertion and the alignment of the threaded stem 231 with the screw nut 310.

[0127] The screw nut 310 is, advantageously, defined by a continuous helix, preferably with a plurality of turns.

[0128] The possibility that the screw nut is formed of a discontinuous helix or one or more discontinuous turns (e.g. which can be opened if necessary) cannot be ruled out.

[0129] The knob 31 in the example shown is defined, as a whole, by a monolithic body (separate from the tie rod 20), e.g. made of a plastic material (obtained by injection moulding).

[0130] In such a first embodiment, it is possible to provide that the device 10 optionally comprises a ring nut or protective washer, illustrated only schematically in hatches in Figure 1 as it is of a known type, (made in a separate body from the presser 30 and the tie rod 20), which is adapted to be axially interposed - in operation - between the transverse element 21 and the presser 30, i.e. between the presser and the visible surface P1 of the tiles P resting on the transverse element 21.

[0131] The protective ring or washer is of a known type, e.g. of the type described and shown in Patent no. EP3298213 and no. EP3567183 on behalf of the same Applicant.

[0132] In a second embodiment shown in Figures 17-24, the device 10 is of the "wedge" type. In this second embodiment, the tie rod 20 may comprise a pair of (identical) stems 22 spaced (by a non-zero distance) and parallel to each other.

[0133] Each of the stems 22 has the characteristics described above.

[0134] A respective transverse element 21 is attached to the first end 221 of each stem 22, wherein the transverse elements 21 are (identical to each other and) parallel to each other (i.e., have parallel longitudinal axes) and coplanar, i.e., the rest planes defined by the upper surface 211 of each of them are coplanar.

[0135] In practice, the transverse elements 21 are arranged with their longitudinal axes parallel (and coplanar) and are placed side by side with each other, at a non-zero distance, with respect to a flanking direction orthogonal to the longitudinal axes thereof (and parallel to the rest plane defined by them).

[0136] Each of the transverse elements 21 individually has the characteristics described above. The transverse elements 21 are separated from each other (i.e. spaced by a non-zero distance and substantially independent).

[0137] Particularly in this second embodiment, each stem 22 has (individually) a predetermined torsional elasticity (defining, as such, a torsion bar itself).

[0138] In practice, each stem 22 (elastically twisting around its own central axis) is configured to allow a rotation of the transverse element 21 joined to the first end 221 of the stem 22, around the central axis of the stem itself, of at least 90° (preferably of an arc between 90° and 180°) with respect to the respective second end 222, starting from an unperturbed starting position, without plastic yielding of the stem 22, and - furthermore - to allow the elastic return of the transverse element 21 to the unperturbed starting position. Preferably, the torsional elastic rigidity of each stem 22, i.e. the torque defined by the elastic response of the stem 22 (upon release of the perturbation), is configured to allow a rotation of the transverse element 21 immersed in a resistant viscous fluid - such as the tile-laying glue that has not yet fully hardened or "fresh" - so as to be able to move the not-yet-hardened glue insisting on the sidewall 212 (at the front in the direction of rotation back towards the starting position) of the transverse element 21.

[0139] In this second embodiment, the abutment body 23 comprises (or consists of) a crosspiece 232 which joins the second top ends 222 of the two stems 22 (and is arranged with its longitudinal axis parallel to the flanking direction, as well as parallel to and at a distance from the rest plane defined by the upper surface 211 of each transverse element 21).

[0140] The crosspiece 232 is made in a single (monolithic) body with the stems 22.

[0141] For example, the median plane orthogonal to the longitudinal axis of each transverse element 21 is, preferably, also a median plane of the crosspiece 232 on which its longitudinal axis lies.

[0142] The crosspiece 232, which - as said - extends longitudinally with its own longitudinal axis parallel to the flanking direction of the transverse elements 21 and stems 22, comprises a transverse section (with respect to a plane orthogonal to the median plane and orthogonal to this flanking direction) defining a thicker area in an area proximal to the second end 222 of the stems 22 and with entire longitudinal development.

[0143] The crosspiece 232, in general, has a predetermined torsional and/or flexural strength, e.g. greater than or equal to the torsional strength of the stems 22 and/or greater than or equal to the tensile strength of the stems 22 themselves.

[0144] Preferably, such torsional and/or flexural strength is such that it prevents or severely limits torsion and/or flexion of the crosspiece 232 under the action of the usual pressures and/or forces involved during operations of levelling the laying tiles P.

[0145] This thicker zone defines a reinforcing beam for the crosspiece 232.

[0146] This thicker area is overlapped at the top by a thinner grip portion, which defines the handle element 24 of the device 10, and is connected to each rod 22 by means of a respective connection section 2320, e.g. (inverted) truncated-cone, which acts as a reinforcement.

[0147] The crosspiece 232, i.e. the reinforcing beam, has an intermediate area interposed between the stems 22, which is aligned in plan, i.e. is superimposed with respect to a direction orthogonal to the rest plane defined by the upper surface 211 of each transverse element 21, to at least one empty interspace interposed between the two transverse elements 21.

[0148] The reinforcing beam, in the said intermediate area interposed between the stems 22, ends at the bottom with a shaped border, e.g. "V" shaped.

[0149] The distance of the shaped border from the rest plane defined by the upper surface 211 of each transverse element 12 is (abundantly) greater than the thickness of the tiles P to be levelled.

[0150] In addition, the crossbeam 32 may have lightening openings, e.g. blind or pass-through, defined above the reinforcing beam, e.g. In the handle element 24.

[0151] The tie rod 20, in this second embodiment, comprises or defines as a whole a through opening, with the through axis substantially orthogonal to the median plane (of the transverse elements 21 and orthogonal to their longitudinal axes thereof).

[0152] In practice, the tie rod 20 (formed by the two transverse elements 21, the two stems 22 and the crosspiece 232) defines an overall portal/bridge shape that delimits the through opening.

[0153] The through opening is delimited peripherally (at the top) by the crosspiece 232 and (at the sides) by the stems 22 and is open at the bottom (i.e. on the opposite side of the crosspiece 232) at the empty interspace between the two transverse elements 21.

[0154] In more detail, the through opening is delimited at the top by the shaped border of the reinforcing beam of the crosspiece 232, at the bottom it is open and at the sides by the internal facing directrixes of the stems 22.

[0155] In particular, when the device 10 is a "wedge" levelling (spacer) device, the overall through-opening has a substantially rectangular shape to allow the introduction, substantially to size, of such a wedge as a presser.

[0156] In this second embodiment, the presser 30 is then defined by a presser wedge 32 (e.g. separated or joined in some way to the tie rod).

[0157] The presser wedge 32 is a rectangular wedge, e.g. it is provided with a planar end defined by a plane lower surface adapted to be directed, in use, towards the rest plane defined by the transverse elements 21 (i.e. towards the tiles P) and an upper surface inclined with respect to the lower surface and provided with, for example, abutment elements such as teeth or knurls.

[0158] The presser wedge 32 has a variable (and steadily growing) thickness along its longitudinal axis from a tapered end towards the opposite widened end.

[0159] The presser wedge 32 is configured to be axially fitted with a clearance through the through opening defined by the tie rod 20 along an insertion direction orthogonal to the longitudinal axis of the crosspiece 232 and parallel to the rest plane defined by the transverse elements 21.

[0160] For example, the maximum height of the presser wedge 32 is lower than the height of the through opening (i.e. the distance of the shaped border of the crosspiece 322 from the aforesaid rest plane).

[0161] The shaped border of the crosspiece 232 is adapted to engage the teeth of the substantially pop-up presser wedge 32 during the axial insertion of the presser wedge within the through opening along the insertion direction.

[0162] The presser wedge 32 is adapted to be fitted into the through opening by means of a direct axial thrust parallel to the insertion direction from the side of maximum height of the presser wedge 32.

[0163] During such insertion, the upper surface of the presser wedge 32 comes into forced contact with the shaped border of the crosspiece 232 exerting a tensile action on the stems 22 (and their respective transverse elements 21).

[0164] In a third embodiment shown in Figures 25-30, the device 10 is of the "strap" or "ratchet" type.

[0165] In this third embodiment, the abutment body 23 comprises (or consists of) a serrated strap 233 (e.g. on both faces or on one of the two faces) having a longitudinal central axis parallel to and coinciding with the central axis of the stem 22, i.e. orthogonal to the rest plane defined by the upper surface 211 of the transverse element 21.

[0166] The serrated strap 233 axially extends (the second end 222 of) the stem 22.

[0167] In practice, the serrated strap 233 has a lower end joined (directly or indirectly) to the second end 222 of the stem 22 and an opposite free upper end.

[0168] For example, the serrated strap 233 has an axial length equal to or greater (preferably greater, e.g. substantially double) than the axial length of the stem 22.

[0169] The serration of the serrated strap 233 extends, for example, substantially along a prevailing section (or substantially along the entire length) of the serrated strap 233 and, for example, has a constant pitch.

[0170] Preferably, the width of the serrated strap 233 is greater than the transverse dimension (diameter or larger diameter) of the stem 22.

[0171] In such a case, the lower end of the serrated strap 233 is joined to the second end 222 of the stem 22 by means of a connection section 2330, e.g. (inverted) truncated-cone and flattened, which acts as a reinforcement.

[0172] Furthermore, in such third embodiment, the tie rod 20 may comprise - although not strictly necessary - a handle element 24 protruding from the abutment body 23, or protruding from the free upper end of the serrated strap 233, which is configured to be gripped (with two fingers of one hand) to rotate - manually - the tie rod 30 (and with it the transverse element 21) about the central axis of the stem 22.

[0173] For example, the handle element 24 is shaped like the one described above for the first embodiment.

[0174] In addition, in this third embodiment, the presser 30 is configured to slide along the serrated strap 233, engaging it in a pop-up manner.

[0175] Preferably, the pop-up connection is unidirectional, so that the presser element 30 can slide on the serrated strap 233 only when approaching the stem 22 and the transverse element 21.

[0176] The presser 30 comprises a knob or cap 33 having an overall cup or inverted cup shape, e.g. truncated-cone, or a concave shape (with concavity facing the transverse element 21 and/or the tiles P in operation).

[0177] It is not excluded that the cap 33 may have any other shape, such as for example truncated-cone, cylindrical or other suitable shape adapted to be gripped by a hand of a person in charge of the installation for sliding it.

[0178] The cap 33, moreover, has a planar end (and/or coplanar lower feet) facing the transverse element 21 (parallel to the rest plane defined by the upper surface 211 thereof) when the presser 30 is slidably associated on the serrated strap 233 and perpendicular to the longitudinal axis of the serrated strap itself.

[0179] In practice, the planar end is adapted to be turned in use towards the transverse element 21 (or towards the tiles P resting on it) and defines a perfectly planar surface perpendicular to the central axis of the stem 22.

[0180] The presser 30 comprises, in particular, an insertion slot (of the serrated strap 233) provided with at least one tooth 330 configured to couple (with a pop-up coupling) with the teeth of the serrated strap 233.

[0181] For example, the slot with the tooth 330 is defined at a top wall of the cap 33.

[0182] The slot with the tooth 330 passes axially this top wall of the cap from side to side and, for example, at an internal end thereof it may be provided with a lead-in taper to facilitate the axial insertion and the alignment of the serrated strap 233 in the cap 33. Furthermore, in addition to those described above, it is possible to envisage that the device 10 may be of a different type, such as for example a "ring nut" device or other. Finally, it is not excluded that, with the same principle illustrated above for the various embodiments, in which each transverse element 21 is "bi-lobed", the transverse element 21 may be "tri-lobed", to be fitted inside a "T" intersection of two joints (between three adjoining tiles P), and then rotated (by 45°/60°) so that each of the three lobes is placed under the laying surface P2 of each of the three adjoining tiles P.

[0183] In such a case, as shown in Figure 32 (in relation to the first embodiment, since it may however also be envisaged for any other embodiment described above), the transverse element 21 has a first main body (equal to the transverse element 21 of the bi-lobed embodiment described above) and a second auxiliary body branching laterally from the central area of the first main body, along a further longitudinal axis orthogonal to the longitudinal axis of the first main body.

[0184] This second auxiliary body is, in practice, equal to one of the two lobes of the first main body but it is oriented at right angles to them around the central axis of the stem 22.

[0185] Furthermore, it is not excluded that the transverse element 21 may be "four-lobed", to be fitted inside an intersection "X" of two joints (between four adjoining tiles), and then rotated (by 45°) so that each of the lobes is placed under the laying surface P2 of each of the four adjoining tiles P.

[0186] In such a case, as shown in Figure 31 (in relation to the first embodiment, since it may however also be provided for any other embodiment described above), the transverse element 21 has a first main body (equal to the transverse element 21 of the bi-lobed embodiment described above) and a second auxiliary body equal to the first main body, which intersects with the first main body at the respective central zone and develops axially along a further longitudinal axis orthogonal to the longitudinal axis of the first main body.

[0187] This second auxiliary body, in practice, defines two further lobes in relation to the two lobes defined by the first main body, which are oriented at right angles to the lobes of the first main body around the central axis of the stem 22

[0188] In light of the above, the operation of the device 10 is as follows.

[0189] When, during the laying of the P tiles, an unevenness in the levelling of one or more tiles P already laid on the glue is detected (for example an unevenness due to premature or unexpected failure of one or more traditional levelling spacers) and the glue under the tiles P is still fresh or not completely hardened, it is possible to act to level the tiles P by using one or more auxiliary spacers 10 as described below.

[0190] For example, with a device 10, according to the first or third embodiment described above, it is possible to have available a tie rod 20 (or more tie rods 20) and to fit the transverse element 21 thereof into the joint (already formed) between two tiles P placed side by side and arranged on the glue.

[0191] For example, it is possible to fit more than one tie rod 20 into the same joint, preferably at a predetermined distance from each other.

[0192] In practice, as shown in Figures 6-9 and 28, the transverse element 21, with its longitudinal axis parallel to the joint, is inserted into the joint by embedding it in the glue until its rest plane is at a height lower than the laying surface P2 of the tiles P.

[0193] At this point, as shown in Figures 10-11 and 29, for example by gripping the handle member 24, a rotation (of 90°) is applied to the tie rod 20 about the central axis of the stem 22, thereby rotating the transverse element 21 by a corresponding angle (of 90°) about that central axis, and - then - the upper surface 211 of the transverse element 21 is brought below (and in contact with) the laying surface P2 of the tiles P (so that each of the tiles P is superimposed in plan on a respective lobe of the transverse element 21). With the tie rod 20 in this position, the presser 30 is then applied, i.e. the knob 31 is screwed onto the threaded pin 231 (see Figures 12-14 of the first embodiment) or the cap 33 is slid onto the serrated strap 233 (see Figure 30 of the third embodiment), so that it gradually exerts its pulling action on the tie rod 20 until the tiles P are completely levelled. When the glue has finally hardened and is setting on the laying surface P2 of the tiles P, it will be possible to break, e.g. by applying an impulsive force (due to a hammer, kick or similar), the tie rod 20 at the first end 221 of the stem 20 (which is the area where the fracture is triggered due to the geometric - and/or physical - characteristics of the stem-transverse element junction).

[0194] Therefore, the stem 22 (together with the abutment body 23 and the handle element 24) is removed, possibly with the presser 30 associated thereto, in order to be able to proceed with grouting the joints between the lateral sides P3 of the tiles P without the transverse element 21 remaining embedded in the glue being visible on the finished surface.

[0195] The presser 30 can then be reused.

[0196] For example, with a device 10 according to the second embodiment described above, it is possible to have available a tie rod 20 and to fit each transverse element 21 thereof within the joint (already formed) between two tiles P placed side by side and arranged on the glue, it is possible to previously rotate (with the fingers) each transverse element 21 (as shown in Figure 21), for example by 90° with respect to the unperturbed starting position around the central axis of the respective stem 22.

[0197] In practice, as shown in Figures 21 and 22, each transverse element 21, with its longitudinal axis parallel to the joint, is inserted into the joint by embedding it in the glue until its rest plane is at a height lower than the laying surface P2 of the tiles P.

[0198] At this point, as shown in Figure 23, the torsional elasticity of each stem 22 causes each transverse element 21 to rotate (automatically, by elastic response) by 90° around the central axis of the respective stem 22 (in the opposite direction to that previously imposed manually), so that the upper surface 211 of each transverse element 21 is brought below (and in contact with) the laying surface P2 of the tiles P (so that each of the tiles P is superimposed in plan on a respective lobe of the transverse element 21).

[0199] With the tie rod 20 in this position, the presser 30 is then applied, i.e. the presser wedge 32 is inserted into the through opening (delimited at the top by the crosspiece 232 and at the bottom by the visible surface P1 of the tiles P), as shown in Figure 24, so that it gradually exerts its pulling action on the tie rod 20 until the tiles P are completely levelled. When the glue has finally hardened and is setting on the laying surface P2 of the tiles P, it will be possible to break, e.g. by applying an impulsive force (due to a hammer, kick or similar), the tie rod 20 at the first end 221 of each stem 20 (which is the area where the fracture is triggered due to the physical characteristics of the stem-transverse element junction).

[0200] Therefore, the stems 22 (together with the abutment body 23 and the handle element defined by the crosspiece 232) are removed, possibly with the presser wedge 32 still fitted in the through opening, in order to be able to proceed with grouting the joints between the lateral sides P3 of the tiles P without the transverse elements 21 embedded in the glue being visible on the finished surface.

[0201] The presser 30 can then be reused.

[0202] The invention thus conceived is susceptible to many modifications and variants, all falling within the same inventive concept.

[0203] Moreover, all the details may be replaced by other technically equivalent elements.

[0204] In practice, the materials used, as well as the contingent shapes and sizes, may be whatever according to the requirements without for this reason departing from the scope of protection of the following claims.

Claims

1. A tile levelling device configured for the mutual levelling of two or more tiles already laid on a fresh or not fully hardened glue, wherein a joint is defined between the at least two adjacent laying tiles, wherein the device comprises:

- a monolithic tie rod comprising:

at least one transverse element elongated along at least one longitudinal axis and defining a rest plane for at least two adjacent laying tiles;

at least one longitudinal stem protruding from the transverse element with a central axis squared with the rest plane of the transverse element and having a first end joined to the transverse element, wherein a maximum width of the transverse element is equal to or less than a width of the joint defined between the at least two adjacent laying tiles and the stem has a height greater than the maximum thickness of the adjacent laying tiles to be levelled, wherein the stem has a transverse overall dimension equal to or less than the width of said joint; and

at least one abutment body joined to a second end of the longitudinal stem;

the device further comprising:

- a presser adapted to cooperate with the abutment body of the tie rod and configured to exert pressure on the side-by-side tiles.

2. The device according to claim 1, wherein the first end of the stem is joined to the transverse element in a frangible manner.

3. The device according to claim 2, wherein the first end of the stem forms with the transverse element an edge that acts as a fracture trigger line at the stem-transverse element interface.

4. The device according to claim 1, wherein the stem has a constant cross-section over the entire height thereof.

5. The device according to claim 1 or 4, wherein the stem has a cross section having an elongated, preferably elliptical shape, wherein a larger diameter is orthogonal to the longitudinal axis of the transverse element.

6. The device according to claim 1, wherein the stem has a predetermined torsional elasticity, so as to allow a rotation of the transverse element joined to the first end of the stem, around the longitudinal axis of the stem, by at least 90° with respect to the second end, starting from an unperturbed starting position, without plastic yielding of the stem, and the elastic return of the transverse element to the starting position.

7. The device according to claim 1, wherein the abutment body comprises a threaded pin provided with a thread having a parallel screwing axis coinciding with the central axis of the stem and the presser comprises a knob provided with a screw nut that can be screwed on the threaded pin.

8. The device according to claim 1 or 7, the tie rod comprises a handle element protruding from the abutment body and configured to be able to rotate the tie rod about the central axis of the stem.

9. The device according to claim 1, wherein the abutment body comprises a serrated strap and the presser comprises a knob provided with at least one tooth configured to engage the serrated strap in a pop-up manner.

10. The device according to claim 1, wherein the presser comprises a wedge and the tie rod comprises a pair of stems spaced apart from each other by a through opening adapted to be crossed at least partially by the wedge and delimited at the top by a crosspiece that acts as an abutment element and that unites the second end of the stems, wherein a respective transverse element is joined to the first end of each stem, wherein the longitudinal axis of each transverse element is orthogonal to a longitudinal axis of the crosspiece, each stem preferably having a predetermined torsional elasticity, so as to allow a rotation of the respective transverse element joined to the first end of the stem, around the longitudinal axis of the same stem, by at least 90° with respect to the second end, starting from an unperturbed starting position, without plastic yielding of the stem, and the return of the transverse element to the starting position.

11. The device according to claim 1, wherein the tie rod is made of a plastic material.

Drawing