Machine and method for labeling containers

A machine for labeling containers, comprising a transfer drum which can move rotatably, about an axis, with a given peripheral speed and is fed by an unwinding assembly for unwinding a labeling ribbon along an extension of which a plurality of labels are printed continuously, said transfer drum being provided with cutting means, which are mutually angularly spaced apart around said axis and are configured to be activated on command by respective actuation means, in order to carry out a cutting of said labeling ribbon at a separation zone between two consecutive labels, said transfer drum being adapted to transfer, in a rotary motion thereof about said axis, the individual labels, separated after cutting, in contact with corresponding containers which are moved by a conveyor, said unwinding assembly being drivable by a controller configured to command, during the rotation of said transfer drum about said axis, at least one variation of a feeding speed of said labeling ribbon to said transfer drum by said unwinding assembly, with respect to a peripheral speed of said transfer drum, wherein said controller is configured to (i) command an initial slowing of the feeding speed of said labeling ribbon to said transfer drum to less than the peripheral speed of said transfer drum in order to bring said cutting means into alignment with said separation zone, (ii) after the initial slowing, bring the feeding speed of said labeling ribbon to substantially the same as the peripheral speed of said transfer drum and (iii) immediately after beginning of an activation of said actuation means of said cutting means, command another slowing of the feeding speed of said labeling ribbon to said transfer drum to less than the peripheral speed of said transfer drum such that the another slowing occurs during activation of said cutting means to cut said labeling ribbon.