Injection Molding System for Fiber-Reinforced Plastic Parts
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Solution Overview
Problem
Existing injection molding systems for producing fiber-reinforced plastic parts face challenges in adjusting fiber content and length, leading to inflexibility and complexity in production.
Innovation Solution
An injection molding system with a feeding device that allows for easy and flexible adjustment of fiber content and length by directly metering cut fibers into the injection molding machine, featuring a cutting device to customize fiber length and a multi-shaft worm machine with a filter system to prevent clogging, ensuring reliable and homogeneous fiber-plastic mixing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If endless fibers are fed through intake nozzles into the injection molding machine and broken up in a mixing zone, then fiber-reinforced plastic parts can be produced, but the fiber content and fiber length are difficult to adjust
Solution Approach 1:
The system segments the fiber processing into distinct functional modules: a cutting device that separates endless fibers into predetermined lengths, a feeding device that meters cut fibers, and an injection molding device that processes the fiber-plastic mixture. This segmentation enables independent adjustment of fiber length and content while simplifying control of each subsystem.
Solution Approach 2:
The cutting device performs preliminary action by cutting endless fibers into predetermined lengths before they enter the injection molding machine. The feeding device then meters these pre-cut fibers into the plastic material. This preliminary processing enables precise control over fiber length and content without requiring complex in-machine adjustment mechanisms.
2Adaptability or versatility
If a feeding device meters cut fibers directly into the injection molding device, then production flexibility is enhanced, but the risk of fiber clogging in the feeding mechanism increases
Solution Approach 1:
The feeding device acts as an intermediary between the cut fibers and the injection molding device. It includes a hopper that receives cut fibers, a metering mechanism that controls fiber quantity, and a discharge opening that feeds fibers into the plastic material. This intermediary structure enables flexible metering while preventing direct contact between the cutting mechanism and the injection system, reducing clogging risks.
Solution Approach 2:
The feeding device allows independent adjustment of fiber-related parameters including fiber length (determined by the cutting device), fiber content (controlled by the metering mechanism), and feeding rate. By enabling parameter adjustment without changing the fundamental feeding structure, the system maintains reliability while achieving flexibility.
3Ease of operation
If the worm shaft is arranged concentrically in the housing bore and can be displaced along the axis of rotation, then the plastic material and fibers can be discharged into the mold, but the structure becomes more complex compared to a fixed arrangement
Solution Approach 1:
The worm shaft is designed with dynamic capability, allowing it to be displaced along its axis of rotation during the injection process. This displacement enables the worm shaft to effectively discharge the plastic material-fiber mixture into the mold cavity. The dynamic arrangement is controlled through the injection molding device's drive mechanism, providing operational flexibility without requiring complex external discharge 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
Enables the production of fiber-reinforced plastic parts with defined fiber lengths and variable fiber content, enhancing production flexibility and simplicity while maintaining a high level of reliability and quality.
Implementation Method 1
The sucked-in fibers are filtered out of the air flow by the filter device
Implementation Method 2
The sucked-in fibers are filtered out of the air flow by the filter device
Implementation Method 3
the feed screw shafts can strip the filtered-out fibers from the filter device and take them with them
Implementation Method 4
An injection molding worm shaft (12) is arranged concentrically in the housing bore (7) and can be driven in rotation about a first axis of rotation (14) and displaced along the first axis of rotation (14) by means of a conventional drive and lifting device (13) for melting and injecting the plastic material (3) into the mold (9)
Implementation Method 5
in the subsequent homogenization zone (19), the injection molding screw shaft (12) is designed in such a way that the supplied fibers (5) can be mixed into the melted plastic material (3) or the plastic melt
Data Source
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AI summary
An injection molding system (1) for producing fiber-reinforced plastic parts has an injection molding device (2) that includes a housing (6) and a housing bore (7) in the housing. A screw shaft (12) which is driven to rotate about an axis of rotation (14) and can move along said axis of rotation (14) is arranged in the housing bore (7) in order to melt and introduce plastic material (3) into a mold (9). In order to feed fibers (5), the injection molding system (1) further has a feeding device (4) which is designed in such a way that cut fibers (5) can be fed directly into the housing bore (7) through a feed opening (21). The injection molding system (1) of the invention allows for the simple and flexible production of fiber-reinforced plastic parts.