The present invention relates to a device for the support, drive and/or transmission of motion to a diamond wire on machines for cutting natural or agglomerate stones, or rather a device for the support or also transmission of cutting motion to a diamond wire on machines provided with rings in diamond wire, which cut blocks of stone in slabs with pre-determined thicknesses and sizes that are equal to that of the starting block. Embodiments for single wires or multiple wires in combination are included.
The prior art already includes, on machines with rings in diamond wire, transmission of motion carried out by starting with motorised pulleys or drums provided with grooves coated in soft material for the housing of the single diamond wire. Also the return pulleys and drums need the grooves to be coated in the said soft material in order to reduce the contact wear and tear of the diamond wire and the groove of the drum or pulley.
Diamond wire is comprised of a steel wire with several strands on which inserts in diamond material with a greater diameter are anchored at pre-determined distances. The diamond wire actually carries out the cutting of the natural or agglomerate stone by the diamond material rubbing and then cutting inside the stone, which is often very hard, whereas the steel wire only has the functions of support, motion and tightening.
Therefore, the cross-section of the wire is not constant and in wrapping the wire around the grooves of the pulleys, wheels and/or drums represents irregular contact as the inserts and sections of wire between them cannot be in contact with it at the same time. To solve this problem, the prior art uses various types of groove in the pulleys or drums coated in soft material so as to minimise the effect of the irregularity due to the different diameters of the wire and diamond inserts. All the solutions proposed include the assembly of soft coating material, to compose the grooves themselves or also to only coat the grooves, which is fixed to the winding pulley or drum.
In the prior art it is known that with use, the diamond inserts act on the groove coating material, damaging it and requiring it to be replaced before the harder material of the pulley or drum, which is usually metal, is damaged, causing considerable problems to the tightening of the diamond wire and regularity in cutting by the wire itself in the stone block being worked upon. Therefore, the groove coating material must remain in contact with the wheel, drum or pulley on which it is mounted and the prior art includes the vulcanization of the material, when rubber-based. In this way, the material is placed around the wheel, drum or pulley and hardened when in position by vulcanization in the specific curve required so as to make it adhere firmly onto it.
After it has been used for some time, the soft material is gradually worn down and its replacement becomes necessary, as mentioned above, so after removal and replacement it must be vulcanized again. This operation is difficult to carry out, as it must be done on the assembled wheel, drum or pulley. If, as is often the case, the machine is not near the workshop where the vulcanization is carried out, there may be considerable transport costs for the pulley, wheel or drum to be included in the replacement of this soft coating material.
In the specific prior art for drums for multiple diamond wires the Italian patent IT 1309685 is known, which describes a way to make the said soft drum groove coating material easily replaceable. The coating of the grooves is actually achieved with an annular band inserted into the metal grooves of the drum so as to be placed between the diamond wire and the groove in order to avoid direct contact. The replacement of the annular bands can be done with the drum assembled on the block cutting machine with rings in diamond wire.
However, this solution requires the construction of the metal grooves of the drum at pre-determined distances, but which are necessary and sufficient to keep the metal parts between a groove and its adjoining ones, limiting the minimum thickness of the slabs that can be obtained by cutting with two adjoining diamond wires to high values or limiting the cutting to only multiples of the said distance.
Finally, the solution of the technical problem presented in the previous patent is limited to a particular type of machine with diamond wires, which is the one with four drums at the top of the ring that is held during cutting, whereas experience recommends using the drums at the maximum diameter possible in order to prolong the duration of the steel part of the wire. Indeed, drums with a small diameter, from 1.0 to 1.3 metres, stress the wire considerably when it is curved, whereas drums with a large diameter stress it less and, from experience, it has been noted that much longer duration can be achieved if diameters greater than 2 metres are used. The work required of large diameter drums does not allow easy the manufacture and inexpensive transport of drums that are provided with grooves with the said annular bands.
This prior art is subject to considerable improvement with regard to the possibility of producing a device for the support, drive and/or transmission of motion to a diamond wire that overcomes the said drawbacks and permits the greatest possibility for housing the diamond wires at the required gauge.
Therefore, the technical aim that this invention is based on is to embody a way to support, guide and/or transmit rotation motion to the diamond wire rings, in a simple, effective and inexpensive way, given that the prior art indicates that in the wear of the support, drive and/or transmission grooves for the diamond wire there is also considerable wear of the machine parts. Furthermore, as it will be required to be more practical in terms of maintenance, the said device will also allow the user to carry out replacement more inexpensively with respect to the operations that must currently be carried out with the prior art.
Even if not less important, a further technical problem is to be found in the possibility of placing the diamond wires at the required gauge to allow the slabs to be cut to the required thickness, at the same time maintaining the cost-effectiveness of the maintenance operation mentioned above.
This invention solves the above-mentioned technical problem, with a device for the support, drive and/or transmission for diamond wires on machines for cutting natural or agglomerate stones, comprising: at least one pulley, wheel or drum for support and/or drive, provided with at least one groove for holding at least one diamond wire for cutting; soft material placed between the diamond wire and the winding groove of the said wire; characterised by the fact that the soft material is wrapped around the pulley, wheel or drum but not fixed and is interposed in the winding of the diamond wire on it, along the winding arch, and is closed in a ring, similarly to a belt, with the winding of the said ring or belt also on a tightening wheel; furthermore, this tightening is achieved by using adjustment means for the tightening wheel to increase the wheelbase of the pulley, wheel or drum for the support and/or drive of the diamond wire in question.
In a further and advantageous embodiment, the pulley, wheel or drum also carries out the function of transmission of the cutting motion to the diamond wire wound around it.
Furthermore, in another improved embodiment the soft material wrapped in a ring comprises two portions or layers where the inner one, in contact with the pulley, wheel or drum, has functions of tightening and reinforcement with special reinforcing wires embedded in it; the outer layer has the function of compensating for the irregularity in the contact between the diamond wire and the winding groove.
Further still, in a specific embodiment, the ring of soft material is in the shape of a moulded belt provided with a groove on the external surface which is designed to couple with a special groove cut into the said pulley, wheel or drum.
Furthermore, in another specific embodiment, the moulded belt has inclined sides so as to provide a transversal section that resembles a trapezoid.
Further still, in a specific and preferred embodiment, the ring of soft material is in the shape of an annular tape, on the outer layer of which there are equidistant grooves, for housing two or more diamond wires at a distance of at least what is necessary for cutting one or more slabs at the minimum thickness provided for by the machine.
Furthermore, in another specific embodiment the equidistant grooves are placed at a distance which is part of the distance between the diamond cutting wires of the minimum thickness slab provided for by the machine.
Further still, in a specific embodiment, the ring of soft material is in the shape of an annular tape on the outer layer of which there are equidistant grooves, for housing at least two diamond wires at a distance of at least what is necessary for cutting one or more slabs at the minimum thickness provided for by the machine; on the tape there are grooves for housing all the diamond wires for rings provided for on the machine.
Furthermore, in another embodiment, the wheel or drum has wide grooves to house several annular bands alongside each other so as to provide at least the distance necessary between two grooves of adjoining bands for cutting slabs to the minimum thickness provided for by the machine.
Further still, in a specific embodiment, on its internal surface the annular tape has longitudinal profiles for coupling on corresponding circumferential grooves present on the wheel or drum and in the tightening wheel in order to maintain its lateral position.
Finally, in a further embodiment, the annular bands are tightened by at least two tightening wheels which can in turn be adjusted on the relevant support using different adjustment means.
Further characteristics and advantages of this invention, in the production of a device for the support, drive and/or transmission of motion to diamond wires on machines for cutting stone shall be made clearer by the description below of an example of en embodiment provided as a non-limiting example with reference to the four enclosed drawings.
Therefore, in cutting the slab between the diamond wires, held between two grooves 15 of the ends of annular bands 16 which are different but alongside each other, the thickness can be the minimum referred to by the distance P between the diamond wires. However, by using the annular tape 4 with grooves 5 shown in
This embodiment can also be used on pulleys with a single groove 24, or rather for single diamond wires, which is not shown. The tightening of the belt 22 can be obtained by using a special tightening pulley or by tightening the belt between two adjoining pulleys, with either both of them driven or just one of them driving.
When using many annular bands 16 in double the number with respect to the previous figures, as shown in
On completion of the solutions proposed here, in the case of many annular bands 16, in accordance with the invention, a single idler pin is made which supports a single wheel similarly to the wheel 19, which is not shown in the Figures, but in turn is supported on both ends on a single adjustable support on the said slide 28. This solution, with respect to the one shown in
The devices for the support, drive and/or transmission of motion to diamond wires on machines for cutting natural or agglomerate stones described here work as indicated below.
The device for support, drive and transmission in the third embodiment shown in
The rubber used in the manufacture of the belts 23 can easily be vulcanized during production, as the overall dimensions and transport of the belts are similar to that of regular trapezoidal belts. This means that they are very easy to manufacture, transport and maintain.
Further still, the device for the support, drive and transmission 14 of the second embodiment shown in
On the other hand, with an annular band 16 composed of an inner reinforcement layer 20 and an outer layer 21, for the grooves for housing the diamond wires, it is easy to check the wear of the grooves 15 for the diamond wires that is taking place. Indeed, by making the layer with reinforcement wires 20 out of lighter material, which is made easier by the presence of the reinforcement wires, and the outer layer 21 in black vulcanized rubber, the gradual wear in the grooves is highlighted very well by the wear of the outer layer 21 at the bottom of the grooves, where the lighter material, and in particular the reinforcement wires, is visible, so it is immediately easy to see which are the belts with grooves which require service. This differentiation of the layers is possible to achieve also on the single belt and on the annular tape for a multiplicity of diamond wires. Furthermore, in the contact between the diamond wires and the outer layer 21 the wear is greater whereas there is less wear to the reinforcement wires of the inner layer 20, due to the greater resistance to wear provided by the said reinforcement wires and the material of the layer.
Similarly to the belt with a single groove, maintenance is facilitated, with respect to the prior art, as it is not necessary to carry out vulcanization treatments on the drum or pulley, but the annular band, like the belt, can be easily rolled up and sent to anywhere in the world very inexpensively.
Finally, the first embodiment of the device for the support, drive and transmission 1 of motion to the rings in diamond wire 2 as shown in
The maintenance of machines in distant locations can therefore be easily carried out as it is not necessary to modify or operate on the pulleys, wheels or drums described above. The grooves 5, 15 or 22, which are worn and/or damaged by contact with the diamond inserts of the rings of the wire 2, are not applied to the surface of the part inside: pulley, wheel or drum, but on the belt 23, annular band 16 or annular tape 4, which are easy to fold and collapse, unlike the pulley, wheel or drum which can advantageously be manufactured in a single piece and delivered whole even if manufactured with a diameter that may even be over 2.5 metres. Therefore, during maintenance, it is sufficient to send one or more new belts, annular bands or annular tapes and assemble them. These may be manufactured using specific technology, that is, with vulcanization of the rubber that they are advantageously made of, so as to avoid the same operation on the pulley, wheel or drum for the vulcanization of the coatings for the grooves in rubber, which are currently known in the prior art.
Therefore, the advantages of this invention can be summarised as: considerable manufacturing simplification as it is no longer necessary to produce pulleys, wheels or drums with coating in soft vulcanized material to make the duration of their use with the diamond wires known in the prior art sufficiently long. Furthermore, the part where the contact wear between the wheel, pulley or drum for the support, drive and/or transmission is concentrated is the belt with groove, annular band with groove or annular tape with groove which houses the diamond wire(s) and concentrates the contact wear. Further still, the maintenance of the pulleys, wheels or drums included in the invention is greatly facilitated by just being able to change and replace the belt, annular band or annular tape of the invention extremely easily, that is, like a regular trapezoidal or flat transmission belt known in the prior art. This ease of maintenance leads to further economy in the maintenance of the machine, as it is possible to transport just the said belts, annular bands or annular tapes of the invention to be able to carry out the maintenance. As mentioned in the description, the belts, annular bands or annular tapes can be folded, collected and rolled up in the way known in the prior art for the transport of transmission belts so as to considerably reduce the dimensions of the material that is transported for maintenance.
What has been described above enables considerable simplification of the manufacture and management of machines for cutting blocks of natural or agglomerate stone with a multitude of diamond wires, so as to allow large scale economy in manufacture and maintenance, even if pulleys, wheels or drums with large diameters are used, and achieve long-term use of the diamond wires of the rings.
Naturally, many modifications may be made to the device for the support, drive and/or transmission of motion to diamond wire on machine for cutting natural stone described above by technicians that are specialised in the field, in order to comply with specific and contingent needs, all of which, however, are included within the scope of protection of the present invention as defined by the following claims.
Besides, even if less advantageously, the invention as described above may be applied to a pulley, wheel or drum to be used just for the return of the diamond wire, or rather, the belts, the annular bands or the annular tape are used as a mobile coating for the driven pulleys, wheels or drums and not motors or motorised, for the support and drive of one or more diamond wires.
Therefore in a further variation of the invention, even if less advantageously than what has been described, the motorisation of the rings in diamond wire is carried out with the rotating motion generated by an electric motor that transfers it to the wheel for the return and tightening of the belt, annular band or tape, so the said drive transfers the motion to the diamond wire/wires that is/are wound around the pulley, wheel or drum around which the said belt, annular band or tape is wound.
Number | Date | Country | Kind |
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PCT/IT2007/000683 | Sep 2007 | IT | national |
MO2008A000039 | Feb 2008 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IT2008/000618 | 9/26/2008 | WO | 00 | 5/12/2010 |