Abstract: The machine comprises a pair of risers and a head comprising a plurality of operating roller units with rollers supported on the top and between the risers. According to the invention, the machine comprises a cover pivotally mounted by a pin with respect to the risers and over the head so to at least cover the gap on the top and on the front between the risers, in which the operating units are arranged in its closed position. Cams are functionally associated to the cover and cam trackers are functionally associated to a micro switch. The micro switch is electrically connected to the electrical power circuit of an electrical geared motor of the machine so that the micro switch electrically closes the electrical circuit only when the cover is correctly and completely closed and consequently the electrical geared motor of the machine can be turned along with the operating unit rollers only in this condition.

Abstract: The machine comprises a pair of risers (12) and a head (13) comprising a plurality of operating roller units (15.1, 15.2, 15.3) with roller supported on the top and between said risers. According to the invention, said machine comprises a cover (14) pivotally mounted by means of a pin (14.1) with respect to said risers (12) and over said head (13) so to at least cover the gap on the top and on the front between the risers (12), in which said operating units are arranged, in its closed position. Cam means (16, 16.1) are functionally associated to said cover (14) and cam tracker means (17, 17.1) are functionally associated to a micro switch (18).