Patent ID: 7644580

Claim:
A control coupling of pressurized medium in a delimbing and cutting apparatus, provided for feeding members and for changing their feeding speed, said control coupling comprising: a first motor and a second motor coupled in parallel and arranged to drive a first feeding member, the rotational speeds of the motors being bound to each other, a third motor which is a multi-capacity motor comprising a first half-motor and a second half-motor, wherein the second half-motor is coupled in series with the first motor by means of a first line, and arranged to drive a second feeding member, a fourth motor coupled in series with the second motor by means of a second line, and arranged to drive a third feeding member, a first valve member arranged to connect across the first half-motor, to allow free circulation, in a first position, and, in a second position, to couple the first half-motor of the third motor in parallel with the first motor, and a first control member arranged to monitor the pressure in the first line and to let the first valve member move to the first position, when said pressure is lower than a set value.