One-time Injection Molding for Human Bone Model Samples

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing human bone model samples lack the structural integration of cortical and cancellous bone, failing to accurately simulate the mechanical properties and morphology of real human bones.

Innovation Solution

A one-time injection molding preparation method is employed, involving the use of high-density fillers and foaming agents within polymer thermoplastic materials to create samples with bone cortex and cancellous shapes, achieving a more realistic simulation of human bone structure and properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If composite human bone samples are made with polymer materials using different processing techniques for cortical and cancellous bone, then the structural distinction between cortical and cancellous bone is achieved, but interface discontinuities occur and integration effect is lost

Engineering Contradiction:
Improvestructural distinction between cortical and cancellous boneVSAvoidinterface continuity
Core Design Contradiction:
ShapeVSStability of the object's composition

Solution Approach 1:

The patent combines the molding of cortical bone and cancellous bone into a single integrated injection molding process. By designing a unified mold structure with different cavity regions (first cavity for cortical bone, second cavity for cancellous bone) that are connected, the process eliminates interface discontinuities between separate processing steps while maintaining the structural distinction between bone types.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent uses composite polymer materials with different formulations for cortical and cancellous bone regions. The first polymer material has properties matching cortical bone (higher density, greater hardness), while the second polymer material matches cancellous bone (lower density, lesser hardness). This material differentiation enables structural distinction while the single-mold integration ensures interface continuity.

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If solid polymer materials are used for human bone morphology models, then manufacturing simplicity is maintained, but structural distinction between cortical and cancellous bone is lost

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidstructural distinction between cortical and cancellous bone
Core Design Contradiction:
Ease of manufactureVSShape

Solution Approach 1:

The patent segments the mold cavity into distinct regions: a first cavity for cortical bone and a second cavity for cancellous bone. This segmentation allows different polymer materials with appropriate properties to be injected into specific regions, achieving structural distinction while maintaining the simplicity of a single integrated molding process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies local quality by using different polymer materials with specific properties in different regions of the bone model. The first polymer material is formulated to match cortical bone characteristics in the cortical region, while the second polymer material matches cancellous bone characteristics in the cancellous region, achieving anatomical accuracy without complex manufacturing.

Inventive Principle:
Principle #3Local quality

3Stability of the object's composition

If one-time injection molding is used to produce bone samples with cortical and cancellous structures, then structural integration is achieved, but material formulation and process control complexity increases

Engineering Contradiction:
Improveintegration effectVSAvoidmaterial formulation and process conditions
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent employs preliminary action by pre-formulating two distinct polymer materials with properties matched to cortical and cancellous bone before the molding process. The mold is also pre-designed with specific cavity structures and gating systems that automatically direct the appropriate material to the appropriate region. This preliminary preparation simplifies the actual one-time injection process while achieving integrated structural accuracy.

Inventive Principle:
Principle #10Preliminary action

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

The method effectively produces human bone-like samples with mechanical properties and morphology similar to real human bones, including density, hardness, and strength, enhancing their suitability for medical education and simulation purposes.

Implementation Method 1

mixing a foaming agent or other material with lower density than that of the polymer thermoplastic material to achieve the raw materials for the one-time injection molding

Methodology Applied
Scientific EffectFoaming: Foam

Implementation Method 2

granulated by adding a filler with a high density in the polymer thermoplastic material in advance

Methodology Applied
Scientific EffectDensity gradient separation: Density Gradient

Data Source

PatentUS20250050567A1One-time injection molding method for human bone model samples
Publication Date: 2025.02.13 LIU WEIDONG

AI summary

A one-time injection molding preparation method to imitate human bone samples is proposed, and a material database and a bone simulation model library are established that can effectively determine materials and the design process through the finite element method. In the polymer thermoplastic material, the filler with a higher density than the polymer material is first added, After granulation, it is mixed with a foaming agent or a filler with a lower density than the polymer thermoplastic materials. A human bone-like sample is obtained through one-time injection molding technology. This method saves experimental and labor costs and can be produced with traditional processing equipment. The sample is close to the density, hardness, and strength of real human bones, and is more consistent with the morphology and properties of real human bones than samples composed of multiple materials.