WO2012157010A1

WO2012157010A1 - Diamonded tool for grinding and/or squaring paving tiles edges

Info

Publication number: WO2012157010A1
Application number: PCT/IT2012/000140
Authority: WO
Inventors: Ruggero Garbin
Original assignee: Premier S.R.L.
Priority date: 2011-05-17
Filing date: 2012-05-15
Publication date: 2012-11-22
Also published as: ITVI20110123A1

Abstract

A diamond tool (1; 100) for grinding and/or squaring the lateral edges of paving tiles comprising a supporting body (2; 101) made of metallic material, an abrasive layer (3; 102) made of diamond abrasive alloy, facing and stably coupled to the supporting body (2; 101), and a plurality of reinforcement inserts (4), preferably made of metallic abrasive alloy and embedded in the abrasive layer (3; 102) and affixed in the supporting body (2; 101) by interlocking means (5).

Description

DIAMONDED TOOL FOR GRINDING AND/OR

SQUARING PAVING TILES EDGES

The present invention relates to a diamond tool (or diamond wheel) for grinding and/or squaring the edges of paving tiles, which are preferably made of porcelain gres or of natural stones .

As known, the processing of some types of paving tiles, especially if they are made of porcelain gres, which are commonly used for floors and/or walls of building rooms but also for furniture shelves, nowadays requires specific steps for grinding or squaring the lateral edges .

On the contrary, the steps of grinding and/or squaring is not generally performed, for example, on consumer paving tiles .

The processing of grinding and/or squaring the paving tiles edges takes place with the aim, on the one hand, to allow a paving tiles laying without leaks, according to specific aesthetic requirements of the final purchaser, and, on the other hand, to make easier and safer the handling of said paving tiles by removing or smoothing the sharp edge .

This processing stage, which is carried out on the lateral edges of the paving tiles and which is performed on a squaring line, generally provides a first heavy roughing operation, possibly divided into several steps, a subsequent pre- finishing operation and finally a finishing operation which precedes a chamfering operation. The heavy roughing operation is performed with diamond tools, better known as "diamond wheels", which, during the paving tiles processing, are rotated by respective motors on which said diamond tools are keyed.

Moreover, the diamond tools are arranged in pairs facing each other and aligned one with another along two longitudinal directions which are mutually parallel and separated of a distance suitable to allow the automatic feed, typically on rotating belts, of the paving tile being processed.

Generally, the diamond tools (and hence the corresponding motors) are thirty-two, equally divided and distributed along said longitudinal directions . Usually, the first eight diamond tools arranged on both longitudinal directions (with an amount of 16 diamond tools) are provided for roughing two first opposite lateral edges of the paving tiles, while the other eight diamond tools of each longitudinal direction are provided for roughing the other two opposite lateral edges of the paving tiles, which are orthogonal to the above mentioned lateral edges.

After roughing the first two lateral edges of the paving tiles and before roughing the other two lateral edges, the paving tiles are suitably rotated by 90°. The diamond tools which are now used for grinding and/or squaring the lateral edges of the paving tiles have different designs.

A first type of known diamond tools comprises a supporting body, typically made of metallic material, such as steel or aluminum, and a layer abrasive binder, coupled to the supporting body by sintering and containing synthetic diamond.

The abrasive layer is made of metal alloy, for example with a basis of copper, iron, tin, cobalt, nickel, molybdenum (depending on the duration and the abrasion capability of the tool) , or is made of a thermosetting resin, usually with a basis of melamine, which is suitably charged with other substances .

The first five/six diamond tools of each longitudinal direction, which are provided for processing two opposite lateral edges of the paving tiles, generally have an abrasive layer, made of a metal alloy, for heavily roughing said lateral edges, while the other three/two diamond tools of each longitudinal direction include an abrasive layer, made of resin, for completely finishing the lateral edges.

The prior art diamond tools that have been briefly described allow an efficient edge processing of special types of paving tiles, such as the paving tiles made of porcelain gres.

However, the known diamond tools still have some drawbacks, which are connected in particular to their typical mode of use during the processing of the paving tiles lateral edges.

In fact, the diamond tools suitable for a heavily roughing of the paving tiles lateral edges, which are, as mentioned above, five/six for each of the two longitudinal directions along which they are arranged in the relative working machine (with an amount of ten/twelve tools), have non-uniform mechanical wear one relative to the other after the continuous operation cycles.

This is due mainly to the fact that these diamond tools include, as mentioned, a metal alloy abrasive layer, which, due also to its position that is along the squaring line, has a different wear depending on the tool .

Furthermore, the diamond tools with metal alloy abrasive layer inevitably have a wear which is rather different from the wear of the tools with a resin abrasive layer.

This situation often forces the operator to manually intervene on diamond tools subject to wear, by adjusting their position, basically acting on each tool: such action consists in bringing the diamond tools one to the other along one or more of the straight directions, orthogonal to said longitudinal directions, which are identified by the various pairs of diamond tools mutually spaced and facing one to the other, in order to compensate the wear of the abrasive layer.

A further drawback of the prior art comes from the fact that the production of diamond tools which include an abrasive layer made with a metal alloy and which, as seen, are mainly used in the squaring lines of the paving tiles, is more complex, this being reflected in higher production costs, the variable "cost of the labour" being equal.

The present invention is directed to overcome the above mentioned drawbacks of the prior art. In particular, it is a first object of the invention to make a diamond tool for grinding and/or squaring the edges of the paving tiles, which have, under normal use conditions, a lower and in any case more uniform, homogeneous and constant wear, with respect to the known relative diamond tools.

Within said first object, it is an aim of the present invention to provide a diamond tool for grinding and/or squaring the edges of paving tiles which makes easier the work of the operator, who, in a typical squaring line, controls the efficiency of the diamond tools roughing, by managing the operation and the mutual positions .

A further object of the present invention is to provide a diamond tool for grinding and/or squaring the edges of paving tiles that, compared to the prior art, improve the efficiency of the roughing to which the paving tiles are subjected in a squaring line.

Another object of the present invention is to indicate a diamond tool for grinding and/or squaring the edges of paving tiles which has a lower manufacturing cost compared to known diamond tools having equal application, functionality and operational efficiency. A further object of the invention is to make a diamond tool for grinding and/or squaring the edges of paving tiles that allows to design and to install squaring lines which are less expensive those belonging to the state of the art.

The above objects are achieved by a diamond tool for grinding and/or squaring the edges of paving tiles according to claim 1 attached, to which reference is made in short .

More technical details and construction of the diamond tool of the invention are set forth in the corresponding dependent claims

Advantageously, the diamond tool (or grinding wheel) which is the object of the invention, under the normal operations for grinding and/or squaring the lateral edges of the paving tiles, has a wear which is the lower and, in any case, more uniform and homogeneous than known diamond tools, typically in a squaring line, while maintaining a performance at least comparable with respect to said known diamond tools .

The invention provides a single diamond tool which has the operative advantages of a tool with a resin abrasive layer, which is suitable for finishing the lateral edges of the paving tiles, but with a longer life, typical of a tool with a metal alloy abrasive layer.

The diamond tool of the invention has one. or more reinforcing inserts, which are drowned preferably both in the supporting body and in the resin abrasive layer of resin and that, in general, give to the tool:

•structural rigidity;

·duration;

•capability to abrade material during the operation. In a classic squaring line, as described above, the diamond tool of the invention may be conveniently installed starting from the position 1-3 (according to an hypothetical numbering of the diamond tools positions) along each of the two parallel longitudinal directions, thus eliminating or at least reducing to one/two the number of diamond tools with a metal alloy- abrasive layer which need for an effective and satisfactory processing.

The above feature implies, equally advantageously with respect to the prior art, a considerable saving of costs in a squaring line, since, thanks to the invention, it is possible to provide much less, with respect to the traditional squaring lines, diamond tools with a metal alloy abrasive layer, which, as known, have higher costs for each square meter of grinded/squared paving tiles.

Still advantageously, the diamond tool of the present invention, thanks to a wear uniformity better than that of diamond tools with a metal alloy abrasive layer, makes easier the activity of the operator carrying out the control and management of the diamond tools installed in the squaring line.

Moreover, besides the advantages just pointed out, the quality of the grinding and/or squaring processing of the lateral edges of paving tiles is still high and at least equal to the quality obtained with the known traditional diamond tools.

The above mentioned objects and advantages, as well as others which will emerge below, will appear to a greater extent from the following description, relating to preferred embodiments of the diamond tool of the invention, which are given for illustrative and explanatory, but not limiting, purposes, with reference to the enclosed drawings, wherein:

- Figure 1 is a longitudinal sectional view of the diamond tool of the invention;

- Figure 2 is a cross-sectional view of the diamond tool of the invention;

- Figure 3 is a perspective view of a technical detail of Figures 1 and 2 ;

- Figure 3a is an enlargement of a technical detail of Figure 3 ;

- Figure 4 is a partial and simplified cross-sectional view of another embodiment of the diamond tool of the invention.

The diamond tool, technically known as diamond wheel, especially a cup-shaped type diamond wheel or a crown- type diamond wheel, which is the object of the invention and which is able to grind and/or to square the edges of paving tiles, is illustrated in Figure 1 where it is generally indicated with the reference number 1: as noted, the diamond tool 1 includes

- a supporting body 2, made of metallic material;

- an abrasive layer 3, made of diamond abrasive alloy, which faces and which is stably coupled to the supporting body 2.

According to the invention, the diamond tool 1 comprises a plurality of reinforcement inserts 4 which are drowned in the abrasive layer 3 to which are stably coupled by interlocking means, which are generally indicated with 5.

The metallic material of the support body 2 includes any of the metals selected from the group consisting of steel, aluminum and similar materials suitable for the intended use of the body.

The diamond abrasive alloy of the abrasive layer 3 contains synthetic diamond and is preferably of a resin type, such as for example a melamine-based thermosetting alloy.

It is understood that in other variants of the diamond tool of the invention the abrasive alloy of the abrasive layer may be metallic.

In a preferred but not binding embodiment, both the supporting body 2 and the abrasive layer 3 have a thickness between 14 mm and 19 mm, and preferably (as shown in the attached figure) of 18 mm.

In particular, the abrasive layer 3 has a structure shaped as a circular crown and is coupled to a peripheral annular portion 6 of the supporting body 2 by means of joining means, generally indicated with 7. Typically, the joining means 7 include the spontaneous adhesion, by means of sintering, of the material included in the abrasive layer 3, which happens during the diamond tool 1 processing: said connecting or joining means 7 are interposed between the inner surface 3a of abrasive layer 3 and the inner face 2a of the supporting body 2, in correspondence with the peripheral annular portion 6, as shown in Figure 2. The reinforcement inserts 4 are preferably embedded in the resin abrasive layer 3 and only partially in the supporting body 2, to which are coupled by means of the interlocking means 5, which have been previously introduced. More specifically, the reinforcement inserts 4 are arranged consecutively one to each other on the peripheral annular portion 6 of the supporting body 2 and protrude from the inner face 2a so that they are partially embedded in the abrasive layer 3.

Figure 1 also shows that the reinforcement inserts 4 are evenly distributed on the peripheral annular portion 6 of the supporting body 2.

In this regard, it is stressed that corresponding points of each of the reinforcement inserts 4 lie along the same two circles inscribed in the abrasive layer 3 and in the supporting body 2.

It should be noted, however, that in other embodiments of the invention, not shown, corresponding points of each of the reinforcing inserts can lie along same circles, inscribed in the abrasive layer and in the supporting body; the number of said circles is other than 2 and could vary, depending on the construction choices, starting from 1.

Preferably, the reinforcement inserts 4 are also made of metal abrasive binder containing synthetic diamond and, as shown in Figure 3, each of them comprises a substantially parallelepiped straight edge 8 which extends mainly along a linear axis Z.

According to the preferred embodiment of the invention described herein, the interlocking means 5 comprise: - a pair of shaped seats 9, 10 formed in the inner face 2a of the supporting body 2, in each of which two internal undercuts 11, 12 are identified, as shown in Figure 2 ; - a pair of longitudinal ribs 13, 14, better visible in Figure 3 and projecting from the lower side edges 4a, 4b, opposite to each other, of each reinforcement insert 4; the longitudinal ribs 13, 14 are snap forced or placed for mechanical interference or precisely- positioned into the respective internal undercut 11, 12.

More in detail, the longitudinal ribs 13, 14 and the internal undercuts 11, 12 have profiles substantially equal to each other so as to mutually join.

Furthermore, the shaped seats 9, 10 are mutually opposite so as to define a dovetail profile for each seat; in turn, the longitudinal ribs 13, 14 are arranged symmetrically with respect to the linear axis Z, also defining, together with the central body 15 of each of the reinforcement inserts 4, a dovetail profile, which is clearly visible in the enlarged detail of Figure 3a.

As shown in Figure 2, the lower portion 16 of the central body 15 of the reinforcing inserts 4 is also received in the upper part of the shaped seats 9, 10. The stable coupling of the reinforcement inserts 4, which are fitted into the support body 2 according to the invention through the interlocking means 5, ensures high stability, thus avoiding, at the same time, any risk of structural damage of the components, which, on the contrary, may be found when a welding cord or welding points are used.

It is understood that other embodiments of the diamond tool of the invention, not illustrated in the enclosed drawings, can provide that the interlocking means comprise a number of shaped seats other than 2, said number varying according to the number of circles inscribed in the abrasive layer and in the supporting body, as previously defined.

Moreover, in further embodiments of the invention, again not shown, the interlocking means may comprise a single longitudinal rib, which protrudes from one of the two lower lateral edges of each reinforcing insert, and consequently one single internal undercut which is identified from the shaped seats.

Figure 4 shows a possible variant embodiment of the invention wherein the diamond tool, now generally indicated with 100, differs from that just described and illustrated in Figures 1-3 mainly by the fact that the joining means, as a whole indicated with 106, include, as an alternative of this case, an intermediate layer 107 made of pure and neutral resin, which is interposed between the inner surface 102a of the abrasive layer 102 and the inner face 101a of the supporting body 101, in correspondence with the peripheral annular portion 105 of said supporting body 101.

This intermediate layer 107 further facilitates the mutual coupling between the supporting body 101 and the abrasive layer 102, also increasing the stability.

It should be also noted that in figure 4 the reinforcement inserts and the consequent interlocking means are not represented purely for declarative convenience, while being understood that, for the purposes of the technical concept expressed by the invention, they are necessarily provided also for the diamond tool 100 shown in said figure 4.

On the basis of the foregoing, it is understood therefore that the diamond tool for grinding and/or squaring the lateral edges of paving tiles of the present invention achieves the objects and realizes the advantages mentioned above.

It is also emphasized, in particular, that the diamond tool of the invention has a metallic or resin alloy abrasive layer, which constitutes an active component that is involved in processing of the lateral edges of the paving tiles to be rectified and/or squared.

Upon implementation, changes may be made to the diamond tool for grinding and/or squaring the lateral edges of paving tiles of the invention, such as for example interlocking means of reinforcing inserts fixed to the supporting body and/or to the abrasive layer having a different design from the one described above.

In addition, in other embodiments of the invention, not shown in the accompanying drawings, the diamond tool may include a number of reinforcement inserts other than what is shown in the enclosed drawings, this number being able to vary according to the constructive choices, starting from 1.

In addition, there may further embodiments of the diamond tool claimed herein, also not shown, in which the interlocking means connect the reinforcement inserts only with the abrasive layer, or not only to the supporting body but also to the abrasive layer, thus not affecting the advantages of the present invention.

Finally, it is clear that numerous other variations may be made to the diamond tool (or wheel) of the invention, without departing from the novelty principles inherent in the inventive idea expressed here, as well as it is also clear that in the practical implementation of the invention, the materials, forms and dimensions of the details illustrated herein may be any according to requirements, and may be replaced with other details that are technically equivalent.

Where the construction features and techniques mentioned in the following claims are followed by reference numerals or signs, those reference signs have been introduced with the sole purpose of increasing the intelligibility of the claims themselves, and, accordingly, they do not have any limiting effect on the interpretation of each element, which is therefore identified, as an example, by said reference signs.

Claims

1. Diamonded tool (1; 100), especially of the cup type, for grinding and/or squaring paving tiles edges comprising:

- a support body (2; 101) made of metallic material;

- an abrasive layer (3; 102), made of diamonded abrasive alloy, facing and firmly coupled with said support body (2; 101) ,

characterized in that it comprises one or more reinforcement inserts (4) drowned in said abrasive layer (3; 102) and/or said support body (2; 101) with which are firmly coupled through joint means (5) .

2. Tool (1; 100) as claim 1 characterized in that said metallic material of said support body (2; 101) include any of the metals selected from the group consisting of steel, aluminium and similar materials.

3. Tool (1; 100) as claim 1 or 2 characterized in that said diamonded abrasive alloy of said abrasive layer (3; 102) contains synthetic diamond and is of metallic or resin-bonded type.

4. Tool (1, 100) as any of the previous claims, characterized in that said abrasive layer (3; 102) presents a structure in the shape of circular rim and is coupled with a peripheral annular portion (6; 105) of said support body (3; 102) through junction means (7; 106) .

5. Tool (1) as claim 4 characterized in that said junction means (7) include the spontaneous adhesion of the material forming said abrasive layer (3) during the production of said diamonded tool (1) , interposed between the inner surface (3a) of said abrasive layer (3) and the inner face (2a) of said support body (2) at said peripheral annular portion (6) .

6. Tool (100) as claim 4 characterized in that said junction means (106) include an intermediate layer

(107) , made of pure and neutral resin, interposed between the inner surface (102a) of said abrasive layer

(102) and the inner face (101a) of the said support body (101) at said peripheral annular portion (105) and suitable to favour the mutual coupling between said abrasive layer (102) and said support body (101) .

7. Tool (1; 100) as any of the previous claims characterized in that said one or more reinforcement inserts (4) are drowned predominantly in said abrasive layer (3; 102) and only partially in said support body (2; 101) with which are coupled through said joint means (5) .

8. Tool (1; 100) as any of the claims from 4 to 7 characterized in that it comprises a plurality of said reinforcement inserts (4) arranged one consecutively the other on said peripheral annular portion (6; 105) of said support body (2; 101) from the inner face (2a; 101a) of which protrude to be partly drowned in said abrasive layer (3; 102).

9. Tool (1; 100) as claim 8 characterized in that said reinforcement inserts (4) are uniformly distributed over said peripheral annular portion (6; 105) of said support body (2; 101) .

10. Tool (1; 100) as the claim 8 or 9 characterized in that corresponding points of each of said reinforcement inserts (4) lie along at least the same circumference inscribed in said abrasive layer (3; 102) and said support body (2; 101) .

11. Tool (1; 100) as any of the previous claims characterized in that said one or more reinforcement inserts (4) are made of metallic abrasive binder containing synthetic diamond.

12. Tool (1; 100) as any of the previous claims, characterized in that each of said reinforcement inserts (4) comprises a substantially parallelepiped straightedge (8) developing mainly along a linear axis (Z) .

13. Tool (1; 100) as any of the previous claim, characterized in that said joint means (5) include:

one or more shaped seats (9, 10) made in the inner face (2a; 101a) of said support body (2; 101), in each of which at least one inner undercut (11, 12) is defined;

at least one longitudinal rib (13, 14) projecting from the bottom side edge (4a, 4b) of each of said reinforcement inserts (4) and forced into said inner undercut (11, 12) .

14. Tool (1; 100) as claim 13 characterized in that said longitudinal rib (13, 14) and said inner undercut (11, 12) present substantially equal each other profiles in such a way as to mutually conjugate.

15. Tool (1; 100) as claim 13 or 14, characterized in that said joint means (5) include two of said shaped seats (9, 10) opposite each other so as to define a dovetail profile for each of said shaped seats (9, 10) and two of said longitudinal ribs (13, 14) arranged symmetrically each other with respect to said linear axis (Z) .

16. Tool (1; 100) as any of the claims from 13 to 15, characterized in that the lower portion (16) of said one or more reinforcement inserts (4) is housed in the upper part of said one or more shaped seats (9, 10) .