Finned Injection Nozzle Tip for Molten Plastic Mixing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injection molding nozzles face issues with color streaks and stress-related defects in molded parts due to inadequate mixing of molten plastic and uneven flow paths, leading to discoloration and structural integrity concerns.
Innovation Solution
A novel inner insert with a finned profile and flow channels that break up and remerge the molten plastic flow, creating a serpentine path with staggered and offset fins/channels to enhance mixing and reduce stress, used in two-piece or three-piece nozzle tips.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional smooth-bore nozzles are used, then the structure is simple, but color streaks and stress-related defects occur due to inadequate mixing of molten plastic
Solution Approach 1:
The nozzle internal bore is segmented into multiple flow channels by adding fins, dividing the single flow path into several parallel channels that merge at the exit. This segmentation creates multiple flow streams that mix upon convergence, improving color blending while maintaining a relatively simple overall nozzle structure.
Solution Approach 2:
The fins extend radially outward from the central axis into the flow path, adding a radial dimension to the otherwise axial flow. This dimensional change creates the serpentine flow pattern and enhances mixing without requiring complex multi-component assemblies.
2Reliability
If single flow path nozzles are used, then the flow path is direct, but stress-related defects occur due to uneven flow distribution
Solution Approach 1:
The flow path is divided into multiple segmented channels by the fins, creating several parallel flow paths that distribute the molten plastic more evenly. This segmentation prevents localized stress concentrations and improves the structural integrity of the molded parts.
Solution Approach 2:
The fins are arranged to create a serpentine (curved) flow path rather than a straight line, causing the molten plastic to follow a winding route through the nozzle. This curved path promotes better mixing and more uniform flow distribution, reducing stress-related defects.
3Manufacturing precision
If fins are added to create flow channels, then mixing of molten plastic is improved, but the nozzle manufacturing complexity increases
Solution Approach 1:
The fin structure segments the flow path into multiple channels, creating effective mixing through flow separation and recombination. This segmentation approach achieves good mixing quality while maintaining manufacturability through relatively simple machining operations.
Solution Approach 2:
The number, position, and orientation of the fins can be adjusted as design parameters to optimize mixing performance. By varying these parameters, different mixing intensities and flow patterns can be achieved without fundamentally changing the manufacturing process.
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 solution improves color blending and reduces stress within molded parts, eliminating streaks and preventing cracks at the gate area, while maintaining structural integrity by providing additional flow paths for molten plastic.
Implementation Method 1
The finned profile and its associated flow channels cause the flow of molten plastic in the nozzle to go through a breakup into the flow channels before it is merged at the nozzle flow exit. This breaking up of the molten plastic flow and its merging insures a better mixing of the molten plastic
Data Source
AI summary
A series of injection molding nozzle tips having a novel inner insert. The novel inner insert in accordance with the embodiments of the present invention includes a finned profile having flow channels between the finned sections. The finned profile and its associated flow channels cause the flow of molten plastic in the nozzle to go through a breakup into the flow channels before it is merged at the nozzle flow exit. This breaking up of the molten plastic flow and its merging insures a better mixing of the molten plastic and also reduces stresses within the molded part.