WO2014029734A1

WO2014029734A1 - Diamond bead for cutting stone-like material

Info

Publication number: WO2014029734A1
Application number: PCT/EP2013/067239
Authority: WO
Inventors: Alessandro Cappeller; Giovanni Marchetti
Original assignee: Mollificio Cappeller S.P.A.; Mondial Stampi S.R.L.
Priority date: 2012-08-24
Filing date: 2013-08-19
Publication date: 2014-02-27
Also published as: ITPD20120249A1

Abstract

A diamond bead (10) for cutting stone-like material, comprising a central supporting element (11), provided with a through opening (12), and a diamond annular cutting body (13), which is fixed so as to surround the central supporting element (11). The central supporting element (11) is constituted by a wire (14) made of metallic material which is shaped according to a helical geometry and externally to which the annular cutting body (13) is fixed.

Description

DIAMOND BEAD FOR CUTTING STONE-LIKE MATERIAL

The present invention relates to a diamond bead for cutting stone-like material.

Diamond wires are widely used for cutting stone-like material in quarries, both in quarry-cutting and for the squaring of blocks.

Such diamond wires, of which a portion is shown for the purposes of example in Figure 1 , are generally constituted by a steel cable A, indicated by a dotted line in the figure, on which between thirty and forty diamond beads B and C are normally inserted per meter, such diamond beads constituting the cutting edge of the diamond wire D.

The diamond beads are borne by the wire together with other components, such as spacers E or other similar elements, which are interposed between two consecutive beads.

The most common diamond beads known today are constituted by: - a central supporting element, which has a through hole for joining, in the direction of the axis of the hole, with a spacer, which in turn is perforated for the passage of the steel cable,

- a diamond annular cutting body, which is fixed so as to surround the central supporting element; such annular cutting body is generally provided by sintering around the central support, which is subsequently brazen for joining with it.

Nowadays the central supporting element is constituted by an internally threaded bushing, where the inner threading enables the grip of the plastic material with which the spacers are made, by overmolding between two consecutive diamond beads.

Such internally threaded bushing is obtained from a solid bar in a relatively expensive manner by way of numerous mechanical processing steps with removal of material with machine tools, and with the use of dedicated machines.

The provision of such internally threaded bushings thus involves both an upstream investment in terms of machines, and a considerable waste of raw material, owing to mechanical processing.

The aim of the present invention is to provide a diamond bead for cutting stone-like material, which is capable of overcoming the above- mentioned drawbacks of conventional beads.

Within this aim, an object of the invention is to provide a diamond bead that can be provided without costly processing using machine tools and without waste of raw materials.

Another object of the invention is to provide a diamond bead with performance levels that are at least equal to those of conventional beads.

Another object of the invention is to provide a diamond bead that can be used to provide diamond wires using the same apparatuses and the same methods with which diamond wires comprising conventional diamond beads are made.

Another object of the invention is to provide a diamond bead for cutting stone-like material, which can be made using conventional systems and technologies, at a much lower cost than conventional diamond beads.

This aim and these and other objects which will become more evident hereinafter are achieved by a diamond bead for cutting stone-like material, which comprises

- a central supporting element, provided with a through opening,

- and a diamond annular cutting body, which is fixed so as to surround the central supporting element, characterized in that said central supporting element is constituted by a wire made of metallic material which is shaped according to a helical geometry and externally to which said annular cutting body is fixed.

Further characteristics and advantages of the invention will become more apparent from the description of a preferred, but not exclusive, embodiment of the diamond bead according to the invention, which is illustrated by way of non-limiting example in the accompanying drawings wherein:

Figure 1 is a sectional side view of two conventional diamond beads with a spacer interposed;

Figure 2 is a sectional side view of a diamond bead according to the invention;

Figure 3 is a side view of a detail of a diamond bead according to the invention;

Figure 4 is a sectional side view of two diamond beads according to the invention diamond beads with a spacer interposed.

With reference to the figures, a diamond bead for cutting stone-like material, according to the invention, is generally designated with the reference numeral 10 and comprises:

- a central supporting element 11 , provided with a through opening

12,

- and a diamond annular cutting body 13, which is fixed so as to surround the central supporting element 11.

The central supporting element 11 is constituted by a wire made of metallic material 14, clearly visible in Figure 3, which is shaped according to a helical geometry and externally to which the annular cutting body 13 is fixed.

Such metallic wire shaped according to a helical geometry 14 has a cross-section such that the inner 14a and outer 14b surfaces have undercuts 30 and 31 which are adapted to facilitate the grip, internally of the spacers 18 which are overmolded in plastic material, and externally of the filler material 22 for fixing by brazing to the annular cutting body 13, as described in more detail below.

Such metallic wire is understood to have a cross-section with a profile that is circular, or rounded, or polygonal with rounded corners, or a different similar and equivalent profile, according to necessity and technical requirements. Such metallic wire with helical geometry 14 can be provided in the manner of a helical spring.

The central turns, for example the turns 15, 16 and 17 in Figure 3, of the central supporting element 11 are mutually spaced in order to facilitate the grip of the plastic material of the spacers 18, as in Figure 4, which are interposed between two consecutive diamond beads, for example 10 and 10a, also in Figure 4, of a diamond wire 19 during the molding of the spacers 18 between the diamond beads 10 and 10a.

The central supporting element 11 and the annular cutting body 13 are mutually fixed, for example, by way of brazing.

Between the turns of the metallic wire 14 that forms the central supporting element 11, and the inner surface 20 of the annular cutting body 13, spaces 21 are defined for the filler material 22 of the brazing.

The invention also relates to a diamond wire 19 which is provided with diamond beads 10 and 10a as described above.

In particular, the invention also relates to a diamond wire 19 that comprises a wire, for example made of steel, represented by the dotted line 23, which is inserted in a series of diamond beads 10 and 10a, spacers 18 or other similar elements interposed between two consecutive such beads, characterized in that it has diamond beads 10 and 10a, as described above.

In Figure 4 it is clearly shown that the spacer 18, which is of a conventional type, and molded in a way that is known per se, is formed by molding with its binding portion 24 inside a corresponding diamond bead 10 to which it is coupled, the plastic material of such binding portion 24 being inserted deeply between the central turns, for example 16 and 17, of the central element 11.

In practice it has been found that the diamond bead according to the invention fully achieves the intended aim and objects.

In particular, with the invention a diamond bead has been devised which can be provided without costly processing using machine tools and without waste of raw materials, thanks to the central supporting element made of wire and shaped according to a helical geometry, which can easily be provided in the manner of a helical spring.

Furthermore, with the invention a diamond bead has been devised with performance levels that are at least as high as those of conventional beads, since the annular cutting body 13 is understood as being of a conventional type.

Furthermore, with the invention a diamond bead has been devised which can be used to provide diamond wires using the same apparatuses and the same methods with which diamond wires comprising conventional diamond beads are made, for example by joining the two parts by brazing.

Last but not least, with the invention a diamond bead for cutting stone-like material has been devised which can be made using conventional systems and technologies, at a much lower cost than conventional diamond beads.

The invention, thus conceived, is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. Moreover, all the details may be substituted by other, technically equivalent elements.

In practice the materials employed, provided they are compatible with the specific use, and the contingent dimensions and shapes, may be any according to requirements and to the state of the art.

The disclosures in Italian Patent Application No. PD2012A000249 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, such reference signs have been inserted for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A diamond bead (10) for cutting stone-like material, comprising - a central supporting element (11), provided with a through opening

(12),

- and a diamond annular cutting body (13), which is fixed so as to surround the central supporting element (11), characterized in that said central supporting element (11) is constituted by a wire (14) made of metallic material which is shaped according to a helical geometry and externally to which said annular cutting body (13) is fixed.

2. The diamond bead according to claim 1 , characterized in that said metallic wire shaped according to a helical geometry (14) has a cross- section such that at least one of the inner (14a) and outer (14b) surfaces has undercuts (30, 31).

3. The diamond bead according to claim 1 , characterized in that said metallic wire has a cross-section with a profile that is circular or rounded or polygonal with rounded corners, or a different similar and equivalent profile, said undercuts (30, 31) being defined between the turns.

4. The diamond bead according to the preceding claims, characterized in that the central turns of said central supporting element are mutually spaced in order to facilitate the grip of the plastic material of the spacers interposed between two consecutive diamond beads of a diamond wire during the molding of said spacers between said diamond beads.

5. The diamond bead according to one or more of the preceding claims, characterized in that said central supporting element and said annular cutting body are mutually fixed by brazing.

6. The diamond bead according to one or more of the preceding claims, characterized in that spaces for the brazing filler material are defined between the turns of said central supporting element and the inner surface of said annular cutting body.

7. A diamond wire, comprising a wire inserted in a series of diamond beads, spacers or other similar elements being interposed between two consecutive ones of said beads, characterized in that it is provided with diamond beads according to claims 1 to 6.