Conical Screw Head Agitation for Uniform Resin Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing screw heads in injection stretch blow molding machines lack sufficient agitating performance near the injection position, leading to inefficiencies in plasticizing and kneading molten resin, which affects the production efficiency and temperature uniformity of molded articles.
Innovation Solution
A screw head with a conical shape, protruding agitating blades, and concave grooves is designed to generate a strong swirling flow in the molten resin, enhancing agitating performance near the injection position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional cylindrical screw head with agitating grooves is used, then the structure is simple, but the agitating performance near the injection position is insufficient
Solution Approach 1:
The screw head is changed from a cylindrical shape to a conical shape with a curved surface. This curvature modification enhances the agitating action on the molten resin by creating more effective flow patterns and reducing dead zones, thereby improving agitating performance without significantly increasing structural complexity
Solution Approach 2:
Agitating blades are strategically positioned on the conical surface at specific intervals. This localized arrangement concentrates the agitating action where it is most needed near the injection position, improving productivity while maintaining reasonable structural complexity
2Productivity
If the screw rotation is continued during injection to shorten metering time, then the production efficiency increases, but the temperature uniformity of molten resin deteriorates
Solution Approach 1:
The conical shape of the screw head creates a swirling and turbulent flow pattern in the molten resin during rotation. This mechanical agitation effect enhances mixing and temperature uniformity even during continuous rotation, allowing the screw to maintain both high productivity and temperature uniformity simultaneously
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 enhanced agitating performance improves the efficiency of plasticizing and kneading, reduces temperature unevenness, and shortens the molding cycle, allowing for higher yield and uniformity in molded articles.
Implementation Method 1
the screw head 14 has a conical shape and has a plurality of agitating blades 30 that protrude outward from an axis center of the head 20 in a radial direction
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
Provided are a screw head capable of enhancing agitating performance in the vicinity of an injection position, an injection device, and an injection stretch blow molding machine using the same. The screw head includes a head having a substantially conical shape, a neck portion integrally formed in one axial direction of the head, and a connecting portion integrally formed in one axial direction of the neck portion. In the screw head, the head has a plurality of agitating blades that protrude outward from an axial center of the head in a radial direction and are formed at intervals in a circumferential direction, the agitating blades each have side wall surfaces that extend in the radial direction and a surface that coincides with the circumferential direction, and an acute angle is formed at an intersection of the side wall surface and the surface.