Deformation Prediction for Injection Molded Articles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods fail to accurately predict the deformation of injection molded articles with a base and rib due to shrinkage, especially when filled with anisotropic materials like talc or glass fibers, leading to inaccuracies in dimensional precision and increased development costs.
Innovation Solution
A method and apparatus that identify a support point from the distribution of shrinkage rates to predict deformation, using this point to calculate the bending moment and determine the distribution of shrinkage rates, allowing for precise deformation prediction even in non-freely deforming articles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional prediction methods are used for injection molded articles with base and rib, then the prediction process is simple, but the prediction accuracy of deformation is insufficient
Solution Approach 1:
The prediction method is segmented into distinct functional modules: a support point determination unit that identifies the support point based on shrinkage rate distribution, a bending moment calculation unit that computes bending moments using the support point, and a deformation prediction unit that predicts deformation using the bending moments. This segmentation allows each module to perform its specific function with high accuracy while maintaining overall system clarity and manageability.
Solution Approach 2:
The method performs preliminary determination of the support point based on the distribution of shrinkage rates before calculating bending moments and predicting deformation. By establishing the support point position in advance using the shrinkage rate distribution, the subsequent deformation prediction can be performed with higher accuracy without requiring complex iterative calculations.
2Measurement precision
If free deformation assumption is made, then calculation is simple, but prediction accuracy is insufficient for non-freely deforming articles
Solution Approach 1:
The method applies different treatment to different regions of the molded article by identifying a specific support point location based on the local shrinkage rate distribution. The support point is determined at the position where the shrinkage rate in the rib thickness direction equals the shrinkage rate in the base thickness direction, allowing the calculation to account for local deformation characteristics rather than assuming uniform free deformation throughout.
Solution Approach 2:
The method changes the fundamental parameter from assuming uniform free deformation to calculating actual deformation based on the determined support point position and bending moments. By using the support point position as a key parameter derived from shrinkage rate distribution, the calculation transitions from a simplified assumption to a more accurate model that reflects the actual constrained deformation behavior of non-freely deforming articles.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables simple and accurate prediction of deformation in molded articles, improving dimensional precision and reducing production costs by optimizing design and minimizing prototype iterations.
Implementation Method 1
Such an injection molded article in general shrinks and deforms when the molten state molding material solidifies
Implementation Method 2
an injection molded article is sometimes made to include talc, glass fiber, or another filler having anisotropy so as to improve the strength or add special functions. It is known that if such a filler having anisotropy is included, the anisotropy of the shrinkage rate further increases
Data Source
AI summary
The method of predicting the amount of deformation due to shrinkage of a molded article of the present invention finds a support point P of the bending moment M from a distribution of shrinkage rates of a molding material forming a molded article 10 and uses the support point P to predict the amount of deformation. At that time, it is preferable to use the support point P to find the bending moment M and to use the bending moment M to predict the amount of deformation.