A control coupling of pressurized medium in a delimbingand cutting apparatus, provided for feeding membersand for changing their feeding speed, said controlcoupling comprising at least: a first motor (7) and asecond motor (8) that are coupled in parallel and drive afeeding member (12)； a third motor (9) that is amulticapacity motor comprising a first half-motor (91)and a second half-motor (92) and that is coupled inseries with the first motor (7) and drives a feedingmember (13)； a fourth motor (10) that is coupled inseries with the second motor (8) and drives a feedingmember (14)； first valve members (26) that for thepurpose of free rotation allow the feedback of thepressurized medium exiting the third motor (9) to the firsthalf-motor (91)； and first control members (24, 28, 36,40) that monitor the pressure of a first line (22) andcouple the first valve members (26) to free rotation ifsaid pressure is lower than the set value.
