Máquina de vários fios para cortar blocos de pedra e dispositivo de esticamento de fios

It is a multi-stranded machine for cutting natural or artificial stone blocks comprising: diamond wire rings (2) driven in their cutting motion (m) by a drive drum; a pair of wire guide rollers (5) upstream and downstream of the cutting section (7) to determine in the cutting section the correct position of the single wire in the stone block being processed; a diamond wire ring tensioning device with at least one movable support (18) of a single tensioning element (12) for each diamond wire ring; and which has the tensioning device (9) subdivided into a first tensioning device (10) for large movements, that is, intended for tensioning the diamond wire rings (2) in assembly-maintenance, and a second tensioning device, unique for each wire, for the fine stretching of each diamond wire (2) encased in a ring; both the first and second tensioning devices being oscillated over respective oscillating pins (11, 13, 14) connected to the supporting structure (4); the second tensioning device (12, 18) being alternately subdivided into groups (15, 16), corresponding to the wires they support, even (22) in one group and odd (21) in the other group; finally, the second thin tensor devices being spatially alternated in the groups (15, 16) and those of one group (15, 16) penetrating each other in the space between adjacent tensor devices (12, 18) of the other group (15, 16). 16) and between adjacent diamond strands (21, 22) of the other group, in the various stretching positions that each of the second devices (12, 18) assumes in the stretching.