Method of controlling and regulating the traveling speed of a continuous cigarette rod on a cigarette manufacturing machine

A method of controlling and regulating the traveling speed of a continuous cigarette rod (4) on a cigarette manufacturing machine (1), whereby a continuous strip of paper (5) is fed, through a tobacco loading station (9) and along a continuous rod forming beam (13), to a transverse cutting device (14) by means of a conveyor belt (8) engaging a number of guide pulleys (16, 17, 20, 21) and a drive pulley (18) fitted to a drive shaft (19);

• characterized by the fact that it comprises stages consisting in continuously determining the diameter of the drive pulley (18), for obtaining a first control signal as a function of the surface speed of the drive pulley (18) and, consequently, as a function of the speed of the conveyor belt (8);
• and in comparing said first control signal with a second control signal as a function of the desired surface speed of the drive pulley (18), for obtaining an error signal for controlling the angular speed of said drive shaft (19).