Two-Stage Flow Through Seal Pin for Contamination-Free Blow Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional blow molding processes for plastic containers separate the molding and filling steps, and introduce contamination risks when using the final product as the molding medium, especially with viscous liquids, as they require complex clean-in-place systems to prevent contamination.
Innovation Solution
A two-stage nozzle system for hydraulic blow molding that uses a liquid vector to initiate axial stretching and subsequent radial expansion of the preform, eliminating the need for a traditional stretch rod and allowing the end product to be used as both the molding medium and the content of the container, with a central bore and lateral passageways for controlled flow and a flow straightener to ensure directed injection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the final product is used as the molding medium in hydraulic blow molding, then the container can be formed and filled in a single integrated process, but contamination risks increase especially with viscous liquids
Solution Approach 1:
The nozzle is divided into multiple functional zones: a central bore for primary molding medium injection, lateral passageways for additional medium delivery, and a seal pin mechanism with valve seat for flow control. This segmentation allows different stages of the molding process to be controlled through separate flow paths, enabling integrated molding and filling while maintaining product integrity through precise flow management.
Solution Approach 2:
The seal pin acts as an intermediary mechanism between the molding medium source and the preform. By controlling the seal pin's position relative to the valve seat, the system can regulate when and how the product flows into the preform, enabling the integrated process while preventing contamination through controlled intermediate flow management.
2Shape
If a traditional stretch rod is used in blow molding, then longitudinal stretching of the preform can be initiated, but the system becomes more complex and requires additional components
Solution Approach 1:
The invention extracts and eliminates the traditional stretch rod component by integrating the stretching function directly into the nozzle structure. The central bore and lateral passageways of the nozzle itself perform the stretching function through controlled hydraulic pressure, removing the need for a separate stretch rod and simplifying the overall system.
Solution Approach 2:
The nozzle is designed to combine multiple functions: it serves as both the molding medium delivery system and the stretching mechanism. The central bore and lateral passageways work together to deliver hydraulic pressure that simultaneously forms and stretches the preform, merging what were traditionally separate functions into a single integrated component.
3Object-affected harmful factors
If complex clean-in-place systems are implemented to prevent contamination, then product integrity can be maintained, but the system complexity and cost increase
Solution Approach 1:
The nozzle design enables self-cleaning capabilities through its internal flow paths. The central bore and lateral passageways are configured to allow molding medium flow that naturally flushes and cleans the internal surfaces, maintaining product integrity without requiring complex external clean-in-place systems.
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
This system effectively forms and fills containers without contamination, reducing the need for complex clean-in-place systems and ensuring efficient production by using the end product as both the molding medium and the content, while maintaining product integrity and quality.
Implementation Method 1
the molding medium flowing through the central bore and being ejected from the exit orifice
Implementation Method 2
injecting the molding medium through a central bore of the nozzle into the preform during a first molding stage
Implementation Method 3
a plurality of lateral passageways, the lateral passageways extending laterally from the central portion and each defining a part of the entrance orifice
Data Source
Figure 1A~1C
Figure 2A~2C
Figure 3A~3C
AI summary
A nozzle and system for hydraulic blow molding of a plastic container from a preform. The nozzle includes a nozzle body having a main bore extending therethrough and a seal pin received in the main bore and moveable between a closed position and an opened position. The seal pin include a central bore extending from an entrance orifice to an exit orifice, with the entrance orifice opening into the main bore of the nozzle body.