WO2015181707A1

WO2015181707A1 - Method for recovering waste tyres and elastomeric elongated element obtained with said method

Info

Publication number: WO2015181707A1
Application number: PCT/IB2015/053906
Authority: WO
Inventors: Domenico ZANELLI; Luca CHIECCHIO
Original assignee: Officine Meccaniche Carpenterie Monregalesi - O.M.C.M. Di C. Chiecchio & C. S.N.C.
Priority date: 2014-05-30
Filing date: 2015-05-26
Publication date: 2015-12-03

Abstract

An elongated elastomeric element (1) is obtained from a waste tyre (2) by making on the tread (4) of the waste tyre (2) at least one pair of first cuts (C) and at least one pair of second cuts (E) intersecting the first cuts (C) thus forming a plurality of mutually adjacent blocks (7); the blocks (7) being maintained mutually connected by relative mobility flexible elements (6B) constituting part of the tread (4).

Description

"METHOD FOR RECOVERING WASTE TYRES AND ELASTOMERIC ELONGATED ELEMENT OBTAINED WITH SAID METHOD"

TECHNICAL FIELD

The present invention concerns a method for recovering a waste tyre .

BACKGROUND ART

To recover a waste tyre, it is known, for example from the patent EP 2 113 356, that the sidewalls of the tyre are preliminarily separated from the tread by making two circumferential through cuts, the tubular tread thus obtained is cut crosswise and the tread is flatly disposed forming an elongated element.

In order to facilitate/improve flattening of the tread, it is known from patent EP 6 316 069 Bl that a succession of partial cuts are made on both sides of the tread, extending from a greater side of the elongated element over a predefined length.

Regardless or otherwise of the presence of the cited partial cuts, after the various flattened treads have been spread out, they are arranged side by side to form bands or belts or overlapped to form beams or three-dimensional structural elements .

Even if used, the elongated elements of the type defined above are unsatisfactory for various reasons. Firstly, the elongated element, even in the presence of the above-mentioned partial cuts, continues, in the absence of external pressing loads, to present a residual shape memory both when isolated and, often, also when arranged side by side and connected to the adjacent flattened elements. This limits the field of use of the cited bands and belts due to their poor planarity and heterogeneity in terms of shape. In addition to this, both the elongated elements and the derived bands/belts are difficult to bend or flex, for example, to follow or adapt to curved supporting or reference surfaces . Lastly, the elongated element is almost impermeable, with the exception of the cited sidewalls when provided with the above- mentioned partial cuts, therefore they cannot be applied in stratified structures and, in general, when it is necessary to provide or guarantee passage openings distributed in the elongated element.

Lastly, the through cuts made involve significant difficulty, times and costs since cutting tools have to be used able to cut, on the one hand, the elastomeric material and, on the other, simultaneously the steel mesh embedded in the elastomeric material, taking precautions to maintain a healthy working environment for the operators and avoid environmental pollution . DISCLOSURE OF INVENTION

The object of the present invention is to provide a method for recovering waste tyres, which simply and inexpensively solves the above problems . According to the present invention, a method is provided for the production of an elongated elastomeric element from a waste tyre, the method comprising the steps of making on the tread of said waste tyre at least one pair of first cuts and at least one pair of second cuts intersecting said first cuts, producing a plurality of blocks; and maintaining said blocks mutually connected by flexible relative mobility elements constituting part of said tread. The present invention furthermore concerns an elongated element obtained from a waste tyre.

According to the present invention, an elongated element is produced, as claimed in claim 7.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting implementation example thereof, in which:

figure 1 illustrates, in plan view, a preferred embodiment of an elongated and flattened elastomeric element produced according to the teachings of the present invention;

figure 2 is a section, on an enlarged scale, according to the line II-II of figure 1;

figure 3 is a section, on an enlarged scale, according to the line III-III of figure 1; and

figure 4 illustrates a succession of steps for obtaining the elastomeric element of figure 1; and

figure 5 illustrates, schematically in lateral elevation and substantially in blocks, a preferred embodiment of a machine for producing the elastomeric element of figure 1 from a waste tyre .

BEST MODE FOR CARRYING OUT THE INVENTION

In figure 1, the number 1 indicates an elastically deformable plate element obtained from a waste tyre 2 (figures 4 and 5) comprising two sidewalls 3 and a tread 4. The tread 4 is delimited by two opposite extended surfaces 5,5A of which the surface 5 is a rolling surface. A mesh 6, known per se, of at least partly metallic reinforcing wires 6A is embedded in the elastomeric material of the tread 4 (fig.2) .

The elongated element 1 is obtained by machining the tread 4, as described in detail below, and has two mutually opposite extended greater side surfaces defined by the surfaces 5 and 5A and comprises a plurality of portions or blocks 7 mutually delimiting a plurality of longitudinal passages 8 extending parallel to one long side L of the element 1 and through both the surfaces 5 and 5A. The blocks 7 furthermore delimit a plurality of further transverse passages 9, also extending through both the surfaces 5 and 5A and intersecting the passages 8. In the particular example described, the passages 8,9 are rectilinear and mutually orthogonal. Alternatively, the passages 8,9 mutually form angles different from 90° and/or have at least partly curvilinear paths. The passages 8,9 present respective widths B measured parallel to the surfaces 5,5A mutually equal or different and are crossed by respective sections 6B of the wires 6A which constitute the mesh 6. The sections 6B define respective relative mobility hinges allowing the relative blocks 7 to mutually rotate about at least two instantaneous hinge axes mutually forming angles different from zero. Expediently, the passages 8,9 have widths varying between 0.5 and 5 millimetres, expediently 1 millimetre. The width of the passages 8,9 is, in any case, determined to give the element 1 a desired compliance and/or to guarantee openings crossing the surfaces 5,5A of predefined dimensions or widths.

Expediently, the elongated element 1 is formed using a liquid jet cutting machine 12 which, with reference to figure 5, comprises a fixed base 13, and a motorised rotary table 14 coupled to the base 13 to rotate about a fixed axis 15, in this specific case vertical. According to a variation not illustrated, the axis 14 is horizontal. In any case, the table 14 carries a device 16 for fitting and retention of the tyre 2, known per se and not described in detail .

The machine 12 comprises a robot unit 20, known per se and not described in detail, comprising a jointed arm for moving a liquid cutting head 21 having a nozzle 22 for delivery of a jet of pressurised liquid with or without the addition of abrasive particles. The machine 12 further comprises a collecting tank 24 for collecting the liquid and the parts of elastomeric material removed from the tyre 2 by the liquid jet.

Again with reference to figure 5, the tyre 2 is coupled to the table 14 coaxially to the axis 15 by means of the device 16 and rotated about the axis 15.

During the rotation, by means of the head 21, firstly a plurality of circumferential through cuts C (fig. 4B) are made on the tread 4, the passages 8 are created and, subsequently, a plurality of axial cuts E (fig. 4C) are made to create the passages 9 and delimit the plurality of blocks 7. Obviously the above-mentioned cutting operations can be inverted or alternated according to a predefined cutting program.

Once cutting of the tread 4 has been completed, the sections 6B of the wires 6A crossing one of the passages 9 and those crossing the first two circumferential passages 8 each arranged adjacent to the respective sidewall 3 are cut using a normal cutting disc (not illustrated) . In this way, the sidewalls 3 are separated and spaced from the tread 4 and the same tread 4 is opened, as can be seen in figure 4E . At this point, the cut tread 4 is flatly disposed until it forms the elongated element 1. The flat configuration of the tread 4 occurs practically spontaneously since the tread 4 is practically derived of its shape memory and is able to assume a perfectly flat configuration also in the absence of external actions and/or a predefined curvature.

In addition to this, the cuts C,E and therefore the corresponding passages 8 and 9 define respective crossings of the flattened tread 4 in a plurality of points and along predefined paths which can be chosen at the cutting stage, allowing easy, immediate and stable connection of the element 1 to an underlying support or between two overlapped elements 1 by means of simple application of gluing material or connection in the cited passages.

Lastly, since the sections 6B of the mesh 6 of reinforcing wires 6A are not cut, the element 1 described has greater resistance with respect to the known solutions. Again, the method described for producing the element 1 allows all the cutting operations to be performed up to the stage of flatly disposing the tread 4 without manipulations, i.e. without the need to uncouple the tyre 2 from the supporting table 14.

The use of pressurised fluid as a cutting medium allows the reinforcing wires 6 to be preserved and maintained intact and elastomeric shavings to be obtained in the form of simple spheres which can be easily recovered by the cutting liquid in the tank 24 and can be easily disposed of or re-used. From the above it is evident that the element 1 described can have blocks 7 different from those described in terms of number, geometry and dimensions and, for example, according to the dimensions and orientation of the cuts.

From the above it is also evident that the cuts C,E may not be through cuts or not all be through cuts, i.e. extending through both the surfaces 5, 5A, but blind cuts or grooves made through one single extended surface of the tread. In said case, in addition to the reinforcing wires which may or may not cross the cuts 8,9, also a corresponding elastomeric part of the tread 4 contributes to defining the elastic relative mobility element interposed between the various blocks 7.

Lastly, it is evident that cutting devices different from those indicated could be used for cutting the tread 4.

Claims

1. Method for making an elastomeric elongated element from a waste tyre, the method comprising the steps of executing, on the tread of said waste tyre, at least one pair of first cuts and at least one pair of second cuts intersecting said first cuts thus making a plurality of blocks; and maintaining said blocks connected to each other by mobility flexible elements thereof constituting part of said tread.

2. A method according to claim 1, characterized in that said blocks are kept connected to each other by removing at least part of the elastomeric material during the execution of said first and second cuts and leaving at least part of the reinforcement wires of said tread unchanged.

3. A method according to claim 2, characterized in that said cuts are through cuts and in that during the cut, the metallic wires extending between one block and the adjacent one are left unchanged.

4. A method according to any one of the preceding claims, characterized in that said cuts are carried out using a jet of pressurized liquid.

5. A method according to any one of the preceding claims, characterized in that said cuts are carried out before separating said tread from the sidewalls of the waste tyre.

6. A method according to claim 5, characterized in that the cuts are carried out without uncoupling said tyre from a fixed or rotating supporting table.

7. An elongated elastomeric material element made according to the method of claim 1, the element having two mutually opposite greater side surfaces and a reinforcement mesh of said elastomeric material and extending between said greater side surfaces, characterized in that it comprises a plurality of blocks mutually side-by-side and mutually delimiting passages extending through at least one of said greater side surfaces; relative mobility means being interposed between said blocks and constituting part of said tread.

8. An element according to claim 7, characterized in that said relative mobility means comprise at least part of said reinforcement mesh.

9. An element according to claim 7 or 8, characterized in that said passages are through passages and extend through both said surfaces and in that said relative mobility means extend through said passages.

10. An element according to claim 9, characterized in that said part of said reinforcement mesh is a metallic mesh.