Resin Molding with Two-Stage Vacuum Decompression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing high-speed mold-clamping processes for resin molding result in voids within the molded article due to inadequate air removal, leading to poor physical properties and burrs, while conventional hydraulic press machines operate inefficiently, causing slow mold movement and prolonged cooling, which hampers the production of thin plate resin components with improved thermal conductivity.
Innovation Solution
A molding method utilizing a metal mold with a vertical parting line and a decompression circuit system that includes two stages of vacuum degassing, starting before the resin contacts the upper mold and continuing after, to enhance air removal and mold-clamping speed, while maintaining airtightness and controlling mold movement for faster processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If high-speed mold-clamping is used to improve productivity, then molding speed increases, but air removal becomes insufficient causing voids and poor physical properties
Solution Approach 1:
The decompression circuit is activated before the resin material contacts the upper mold to remove air in advance. This preliminary action prevents air entrapment that would occur during high-speed clamping, allowing fast molding speeds without compromising physical properties due to void formation.
Solution Approach 2:
The decompression circuit operates continuously during the mold-clamping process, maintaining air removal throughout the entire molding cycle. This continuous action ensures that even at high clamping speeds, air is constantly being removed from the cavity, preventing void formation and maintaining product quality.
2Object-generated harmful factors
If horizontal parting line is used to improve air removal, then air can escape better, but resin material flows out causing burrs and requiring post-trimming
Solution Approach 1:
Instead of using a horizontal parting line that allows air to escape but causes resin overflow, the invention uses a vertical parting line configuration combined with decompression. This inverted approach removes air through pressure differential rather than gravitational escape, preventing resin flow out and burr formation while maintaining high productivity.
Solution Approach 2:
The decompression circuit uses pneumatic principles to create negative pressure in the mold cavity, actively drawing air out through designated channels. This pneumatic air removal method replaces the passive gravitational escape of horizontal parting lines, enabling precise control without resin overflow and eliminating the need for post-trimming operations.
3Ease of operation
If hydraulic control is used at upside position of press dead point, then machine operation is simple, but mold movement speed decreases causing prolonged cooling
Solution Approach 1:
Air removal is performed in advance before the resin contacts the mold, and decompression continues throughout the process. This preliminary and continuous action eliminates the need for prolonged cooling periods to ensure complete air evacuation, reducing total cycle time while maintaining simple hydraulic control operation.
4Productivity
If mold temperature is lowered to shorten solidification time, then productivity improves, but surface appearance quality deteriorates
Solution Approach 1:
Air is removed in advance through decompression before the resin fully contacts and cools against the mold. This preliminary air removal eliminates the need for extended cooling times, allowing the mold temperature to be kept higher for better surface appearance while still achieving rapid production through efficient air evacuation.
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 approach significantly improves molding speed, prevents burr formation, and enhances the moldability and flowability of thermoplastic resin composites, enabling the production of resin molded members with improved physical properties and reduced cycle time.
Implementation Method 1
decompressing an inside of the metal mold
Data Source
AI summary
A molding method and a molding system for improving a molding speed of a resin molded member. In the method, firstly a thermoplastic resin composite material is filled in a metal mold (i.e., at time T0), and subsequently a mold-clamping process gets started. As the mold-clamping process progresses, a first decompression circuit starts to decompress an inside of a cavity when the cavity is closed by a sealing member provided on the metal mold. Then, as the mold-clamping process further progresses, the thermoplastic resin composite material thus filled in the metal mold contacts an upper mold of the metal mold (i.e., at time T2). After that, a second decompression circuit starts to decompress the inside of the cavity, thereby to complete the mold-clamping process (i.e., at time T3).