Machine for producing cardboard

An upgrade braking control system for a machine for producing cardboard or corrugated cardboard, having, or in which at least one braking system has been installed, comprising a motor-generator device and a pneumatic mechanical brake device, said system comprising:

• a command and control unit;
• a pressure transducer configured to read a pressure Pm of air along a line coming from the machine for producing cardboard, the pressure being indicative of total torque CL required by the machine, and to translate the total torque CL into an electrical signal to be sent to the command and control unit;
• an electro-pneumatic converter integrated into said upgrade braking control system and operatively connected to said command and control unit, the electro-pneumatic converter of the upgrade braking control system being configured to adjust pressure of the air at a delivery pressure P2 and being connected at the input to an air line at a fixed pressure P1, which is greater than the delivery pressure P2, and, at the output, to an output line;
• a user interface operatively connected to the command and control unit;
• a solenoid valve or a manual two-way valve pneumatically connected:
• i) at the input, to said output line of the electro-pneumatic converter and at a derivation of the air line to the pressure Pm coming from the machine for producing cardboard, and ii) at the output, to a delivery line for delivering air at a braking pressure P3, wherein said delivery line connects the solenoid valve or the manual two-way valve to a mechanical brake device, and wherein said pressure P3 is equal to said pressure Pm when the system is in the deactivated state, or when the system is activated, P3=P2, wherein P2 comprises between 0 and Pm;
• wherein said command and control unit:
• correlates the Pm value received from the pressure transducer with a preset CL value which depends on the pneumatic brake installed on the machine;
• receives a number of revolutions of the motor-generator device and correlates the number of revolutions with a torque CM provided by the motor-generator device;
• calculates the torque CF of the pneumatic brake device;
• commands the electro-pneumatic converter to deliver a pressure P2 corresponding to the torque CF based on calculation of a splitting of the preset braking torque CL to be supplied between a braking torque CF of the mechanical brake device and a braking torque CM of the motor-generator device, wherein, when the torque CM of the motor-generator device is equal or greater than CL, the torque CF of the pneumatic brake device is zero.