Status monitoring of a cutting unit in a food packaging apparatus

A monitoring device, comprising a signal interface for connection to a sensor which is arranged to measure and output a time sequence of measurement values indicative of a cutting resistance for a cutting blade in an apparatus for producing packages of liquid food during a cut performed by the cutting blade to cut a seal formed in a tube filled with liquid food, and logic configured to control the monitoring device to cause the monitoring device to:

• obtain, from the sensor, the time sequence of the measurement values;
• generate a resistance time profile of the cut based on the time sequence of measurement values;
• detect at least one predefined feature in the resistance time profile;
• determine a phase value for the at least one predefined feature within the resistance time profile, wherein the phase value is a time of occurrence of the at least one predefined feature on the resistance time profile relative to a known reference time point on the resistance time profile;
• determine a status of the cutting blade based at least in part on the phase value;
• generate, based on the status of the cutting blade, output data indicating the status of the cutting blade;
• transmit the output data to a module of the apparatus, wherein the output data causes the module to display the status of the cutting blade.

An apparatus for producing packages of liquid food, said apparatus comprising a cutting unit and being configured to vertically seal a web of packaging material in the form of a tube, fill the tube with liquid food, form transverse seals in the tube, and cut the transverse seals with a cutting blade in the cutting unit to sever food-containing packages from each other,

• said apparatus further comprising:
• a sensor which is arranged to measure and output a time sequence of measurement values that represent cutting resistance for the cutting blade when actuated to cut a transverse seal;
• and
• a monitoring device configured to:
• obtain, from the sensor, the time sequence of the measurement values;
• generate a resistance time profile of the cut based on the time sequence of measurement values;
• detect at least one predefined feature in the resistance time profile;
• determine a phase value for the at least one predefined feature within the resistance time profile, wherein the phase value is a time of occurrence of the at least one predefined feature on the resistance time profile relative to a known reference time point on the resistance time profile;
• determine a status of the cutting unit based at least in part on the phase value;
• generate, based on the status of the cutting unit, output data indicating the status of the cutting blade;
• transmit the output data to a module of the apparatus, wherein the output data causes the module to display the status of the cutting unit.