Inflatable Bladder Apparatus for Composite Part Forming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for forming composite parts, such as hot drape forming and male-female die techniques, are limited in forming complex-contoured surfaces, particularly concave surfaces, and often result in fiber distortion and wrinkling, which affect the quality of the finished part.
Innovation Solution
A material forming apparatus comprising an inflatable bladder and a support structure, where the bladder is sealed to the support structure to form a hollow space, and a pressure regulator and actuator are used to apply pressure and move the bladder against a forming tool with complex contours, allowing for precise shaping and minimizing fiber distortion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If hot drape forming is used to form composite parts, then the process is simple and cost-effective, but it is limited to forming parts on tools containing convex surfaces and cannot form parts on tools containing tight concave surfaces
Solution Approach 1:
The patent inverts the traditional forming approach by using a male forming tool with protrusions that press into the composite material, rather than using a female mold with cavities. This inversion allows the forming tool to create both convex and concave surfaces on the composite part, overcoming the limitation of hot drape forming being restricted to convex surfaces only.
Solution Approach 2:
The patent employs a flexible bladder that can be inflated to apply uniform pressure during the forming process. This flexible membrane allows the composite material to conform to complex contours including tight concave surfaces while maintaining process simplicity and avoiding the need for expensive matched male-female die sets.
2Manufacturing precision
If male and female die method is used to form composite parts, then parts with complex contours can be formed, but the method is prone to inducing fiber distortion and wrinkling in the composite material
Solution Approach 1:
The patent changes the pressure application method by using gradual inflation of the bladder rather than immediate mechanical pressing. This controlled parameter change allows the composite material to slowly conform to the forming tool's contours, reducing fiber distortion and wrinkling while still achieving complex shape formation.
Solution Approach 2:
The patent uses pneumatic pressure through an inflatable bladder to apply forming force, replacing direct mechanical contact between male-female dies. This pneumatic approach distributes pressure more evenly and allows the composite material to flow smoothly into complex contours without the localized high-stress points that cause fiber distortion and wrinkling.
3Manufacturing precision
If matching male and female dies are used to form composite parts, then complex contours can be formed, but the dies are costly to make and are not usable for any other parts having different sizes or configurations
Solution Approach 1:
The patent creates a universal forming system where a single male forming tool with protrusions can form multiple different composite part configurations. By changing the bladder size and inflation parameters, the same forming tool can produce parts of different sizes and contours, eliminating the need for expensive matched die sets for each part variant.
Solution Approach 2:
The patent introduces dynamic adjustability through the inflatable bladder system, allowing the forming process to adapt to different part requirements. The bladder can be inflated to different pressures and volumes to accommodate various part sizes and complexities, making the forming tool versatile without requiring multiple fixed die sets.
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 apparatus effectively forms composite parts on complex-contoured surfaces, including concave surfaces, by controlling pressure and movement, reducing fiber distortion and wrinkling, and enabling the use of the same tool for various part configurations.
Implementation Method 1
a pressure regulator and actuator are used to apply pressure and move the bladder against a forming tool
Implementation Method 2
an actuator for moving the support structure and bladder toward a material to be formed
Data Source
AI summary
A material forming apparatus and method for shaping a material to a forming tool having complex contours. The material forming apparatus may comprise a bladder sealed to a support structure, cooperatively forming a hollow space therebetween into which air or another gas may be pumped to inflate the bladder. The forming tool may comprise a protrusion of any shape to which the material may conform. The material may be placed between the bladder and the protrusion and the support structure may be actuated toward the forming tool. As the support structure progresses toward the forming tool, an area of material pressed against the protrusion by the bladder increases in an outward direction. A pressure regulator may regulate an amount of pressure applied to the material by the bladder as the bladder presses the material against the forming tool.