Injection Molding Pressurizing Piston Gas Ingress Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing injection molding apparatuses face issues with gas entering the barrel during the injection process due to volume discrepancies, leading to contamination of molten resin and reduced workpiece quality.
Innovation Solution
The introduction of a pressurizing piston that slides within the torpedo piston, with an energizing mechanism to control volume changes, ensuring that the increase in volume on one side of the cylinder is equal to or less than the decrease on the other side, preventing gas ingress and maintaining resin quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the torpedo is moved in the barrel to a side opposite to the outlet side, then the resin material can be plasticized to molten resin, but the volume increase in the outlet-side space causes gas to flow into the space and mix with the molten resin, reducing workpiece quality
Solution Approach 1:
A pressurizing piston is introduced as an intermediary component between the torpedo piston and the molten resin. This pressurizing piston actively controls the pressure and volume changes in the outlet-side space, preventing gas from flowing into and mixing with the molten resin during the torpedo's movement.
Solution Approach 2:
The system changes the pressure parameter by introducing a pressurizing piston that can adjust and maintain appropriate pressure levels in the outlet-side space. This pressure control prevents gas ingress while allowing the torpedo to move and plasticize the resin material effectively.
2Ease of operation
If the rod is arranged in the first space during plasticization, then the torpedo can be moved to plasticize the resin, but the volume discrepancy between the two spaces causes gas to enter the second space
Solution Approach 1:
The pressurizing piston serves as a mediator that decouples the torpedo movement operation from the gas ingress problem. It allows the torpedo to move freely for plasticization while independently controlling the pressure environment in the outlet-side space to prevent gas entry.
Solution Approach 2:
The internal space of the barrel is segmented into two independently controlled zones: the first space where the torpedo moves for plasticization, and the second space where the pressurizing piston controls pressure to prevent gas entry. This segmentation allows each zone to be optimized for its specific function.
3Productivity
If the plunger is fixed to the rod and moved toward the outlet, then the supply hole can be closed and resin can be injected, but the rod arrangement creates volume imbalance that allows gas flow
Solution Approach 1:
The pressurizing piston acts as an intermediary that maintains pressure control during high-speed injection operations. It prevents gas contamination even when the plunger moves quickly toward the outlet, allowing high productivity without compromising resin quality.
Solution Approach 2:
The pressurizing piston is positioned and activated in advance to establish proper pressure conditions in the outlet-side space before the plunger completes its movement. This preliminary pressure control prevents gas from entering during the subsequent high-speed injection phase.
Data Source
AI summary
An injection molding machine that contributes to improving the quality of a workpiece is provided. An injection molding machine configured to causes torpedo pistons to be slid in one way to thereby plasticize a resin material supplied to a first space of a cylinder, and causes a molten resin to flow into a second space of the cylinder and causes the torpedo pistons to be slid in the other way to thereby inject the molten resin. The injection molding machine includes pressurizing pistons inserted into the torpedo pistons so that the pressurizing pistons can be slid in such a way that an amount of protrusion of the cylinder into the second space of the cylinder with respect to the torpedo pistons is changed, and energizing means for energizing the pressurizing pistons toward the second space of the cylinder.