Cutting Unit Status Monitoring via Resistance Time Profile Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for monitoring the status of cutting units in food packaging machines lack reliability and fail to detect additional fault conditions, leading to potential production standstills and quality issues due to premature or late replacement of cutting blades.

Innovation Solution

A method that involves obtaining a time sequence of cutting resistance measurement values, processing them to generate a resistance time profile, detecting predefined features, determining phase values, and assessing the cutting unit's status based on these phase values and other input parameters, enabling more robust monitoring and detection of faults such as wear, timing issues, and increased friction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If knives are replaced based on running hours, then production standstill is avoided, but unnecessary replacement occurs leading to loss of time

Engineering Contradiction:
Improvecutting unit status monitoring reliabilityVSAvoidproduction standstill time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces the conventional time-based replacement system with a sensor-based monitoring system that measures cutting resistance in real-time. Pressure sensors detect the actual cutting conditions and feed this data to a processing unit that determines when the cutting blade actually needs replacement, substituting mechanical time-based scheduling with electronic condition-based monitoring.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The system implements continuous feedback by measuring cutting resistance through pressure sensors during operation, processing this data to generate resistance time profiles, and using this information to dynamically determine replacement timing. This closed-loop feedback system allows the cutting unit status to be monitored and responded to in real-time rather than following a predetermined schedule.

Inventive Principle:
Principle #23Feedback

2Measurement precision

If cutting resistance monitoring is implemented, then knife wear detection is improved, but additional fault conditions cannot be identified

Engineering Contradiction:
Improvecutting resistance measurement precisionVSAvoidfault condition detection capability
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent segments the cutting process into distinct phases by analyzing features in the resistance time profile, such as the initial penetration phase, the cutting through phase, and the completion phase. By identifying and analyzing specific features within the overall cutting cycle, the system can detect not only wear but also timing issues, friction problems, and other fault conditions affecting different stages of the cutting process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system transitions from scalar resistance measurement to temporal profile analysis by examining resistance values over the entire cutting cycle. This dimensional expansion from a single resistance value to a time-based profile enables detection of multiple fault types by analyzing the shape, features, and characteristics of the resistance curve throughout the cutting process.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Reliability

If prior art monitoring techniques are used, then knife replacement can be detected, but reliability is insufficient for production environment

Engineering Contradiction:
Improvemonitoring technique reliabilityVSAvoidmonitoring system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent creates a universal monitoring system that can detect multiple types of faults (wear, timing issues, friction problems) using a single integrated platform. The pressure sensors, processing unit, and analysis algorithms work together to provide multi-functional monitoring capability, making the system adaptable to various fault conditions without requiring separate dedicated systems for each type of detection.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3974131B1Status monitoring of a cutting unit in a food packaging apparatus
Publication Date: 2024.07.10 TETRA LAVAL HOLDINGS & FINANCE SA
  • EP3974131B1 patent drawingFigure 1A~1C
  • EP3974131B1 patent drawingFigure 2A~3A
  • EP3974131B1 patent drawingFigure 3B~3C

AI summary

The status of a cutting unit (165a, 165b) in an apparatus for producing packages of liquid food is monitored based on a time sequence of measurement values from a sensor (30), e.g., a pressure transducer, which is arranged to measure cutting resistance for a cutting blade (166a, 166b) in the cutting unit when actuated to perform a cut to sever food-containing packages (106) from each other. The monitoring comprises generating a resistance time profile for the measurement values, detecting at least one predefined feature in the resistance time profile, determining a respective phase value for the predefined feature(s), and determining the status of the cutting unit (165a, 165b) as a function of a set of input values comprising the respective phase value. The status may represent the degree of wear of the cutting blade (166a, 166b).