Machine Learning Device for Injection Molding Shrinkage Prediction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current mold design for injection molding faces challenges in accurately predicting molding shrinkage ratios, particularly due to variations in resin type, additive composition, and molding conditions, leading to increased costs and inefficiencies from repeated trial and error processes.

Innovation Solution

A machine learning device and design support system that acquire input data on molding conditions, including resin type, additive ratio, and mold temperature, and use supervised learning to generate a learned model predicting molding shrinkage ratios in both flow and vertical directions, allowing for precise prediction and optimization of mold design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional trial and error methods are used for mold design, then molding shrinkage ratios can be obtained through actual measurement, but the number of trials increases leading to higher costs and longer development time

Engineering Contradiction:
Improvemolding shrinkage ratioVSAvoiddevelopment time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by performing flow analysis and residual stress analysis during the design phase to predict volume shrinkage and birefringence distribution before actual molding trials. This allows the molding shrinkage ratio to be calculated in advance based on the relationship between degree of birefringence and shrinkage anisotropy, eliminating the need for multiple trial mold manufacturing cycles.

Inventive Principle:
Principle #10Preliminary action

2Measurement precision

If traditional trial and error methods are used for mold design, then accurate molding shrinkage ratios can be obtained, but the number of mold manufacturing trials increases leading to higher costs

Engineering Contradiction:
Improvemolding shrinkage ratioVSAvoidmanufacturing cost
Core Design Contradiction:
Measurement precisionVSLoss of energy

Solution Approach 1:

The patent replaces the mechanical trial-and-error system with a computational system. Flow analysis and residual stress analysis are used to calculate volume shrinkage and predict birefringence distribution, which then allows calculation of molding shrinkage ratios through the established relationship with shrinkage anisotropy. This substitutes physical mold manufacturing trials with computational predictions.

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

3Adaptability or versatility

If molding conditions are set without advance prediction, then flexibility in design is maintained, but experience is required and multiple trials are needed to determine optimal conditions

Engineering Contradiction:
Improvedesign flexibilityVSAvoidmolding shrinkage prediction accuracy
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent implements feedback by using the calculated volume shrinkage and predicted birefringence distribution to determine the molding shrinkage ratio through the relationship with shrinkage anisotropy. This feedback loop allows accurate prediction of molding shrinkage based on flow analysis and residual stress analysis results, enabling precise mold design without requiring operator experience or multiple trials.

Inventive Principle:
Principle #23Feedback

Data Source

PatentUS11602876B2Machine learning device and design support device
Publication Date: 2023.03.14 FANUC LTD
  • US11602876B2 patent drawing
  • US11602876B2 patent drawing
  • US11602876B2 patent drawing

AI summary

A molding shrinkage ratio is predicted according to molding conditions set in advance in designing a mold. A machine learning device includes an input data acquiring unit that acquires input data including any molding condition including a type of resin, a type of additive, a blending ratio of the additive, a surface temperature of a mold, and a product of a holding pressure and a holding pressure time for any article molded by any injection molding machine, a label acquiring unit that acquires label data indicating a molding shrinkage ratio in a flow direction and a molding shrinkage ratio in a vertical direction perpendicular to the flow direction of a resin measured of the article molded at the molding condition, and a learning unit that executes supervised learning using the input data and the label data, and generates a learned model.