Overmolded Liftgate Reinforcement Bracket for Lightweight Rigidity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liftgates, whether made of stamped sheet metal or polymer materials, face issues with weight, cost, and structural rigidity, particularly in stress areas like hinge points and latching points, necessitating additional reinforcements.
Innovation Solution
A liftgate formed with a thermoplastic overmolded around preselected reinforcements, incorporating a pair of separate reinforcement plates and a 3D reinforcement plate connected between them, with additional connections to enhance stiffness, using existing connection points for ball joint and hinge brackets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If stamped sheet metal assemblies are used for liftgates, then strength and robustness are improved, but weight and cost increase due to heavy materials and complex hinges
Solution Approach 1:
The liftgate employs a composite construction combining thermoplastic polymer material with embedded steel reinforcement plates at stress points. This composite approach provides the strength of metal where needed while maintaining the weight advantages of polymer materials in non-critical areas, resolving the contradiction between strength and weight.
Solution Approach 2:
Steel reinforcement plates are strategically placed only at critical stress areas such as hinge points, latching points, and corner areas rather than throughout the entire liftgate structure. This localized reinforcement provides necessary strength at critical points while minimizing overall weight compared to full metal construction.
2Weight of moving object
If strictly polymer materials are used for liftgates, then weight and cost are reduced, but strength and rigidity decrease leading to flexing issues
Solution Approach 1:
The liftgate employs a composite construction combining thermoplastic polymer material with embedded steel reinforcement plates at stress points. This composite approach provides the strength of metal where needed while maintaining the weight advantages of polymer materials in non-critical areas, resolving the contradiction between strength and weight.
Solution Approach 2:
Steel reinforcement plates are strategically placed only at critical stress areas such as hinge points, latching points, and corner areas rather than throughout the entire liftgate structure. This localized reinforcement provides necessary strength at critical points while minimizing overall weight compared to full metal construction.
3Strength
If steel reinforcements are added at stress areas, then strength is improved, but device complexity and part count increase
Solution Approach 1:
Multiple reinforcement functions are merged into integrated reinforcement plates that simultaneously strengthen hinge points, latching points, and corner areas. The thermoplastic overmolding process also merges the reinforcement plates with the surrounding structure, creating a unified component that reduces overall part count while maintaining necessary strength.
Solution Approach 2:
The thermoplastic overmolding process creates a composite structure where the polymer material bonds to the steel reinforcement plates, forming an integrated assembly that functions as a single unit. This reduces complexity compared to separate mounted reinforcements while providing comprehensive strength at stress points.
4Strength
If more reinforcements are added to improve rigidity, then stiffness is improved, but weight and material usage increase
Solution Approach 1:
Steel reinforcement plates are strategically placed only at critical stress areas such as hinge points, latching points, and corner areas rather than throughout the entire liftgate structure. This localized reinforcement provides necessary strength at critical points while minimizing overall weight compared to full metal construction.
Solution Approach 2:
The liftgate employs a composite construction combining thermoplastic polymer material with embedded steel reinforcement plates at stress points. This composite approach provides the strength of metal where needed while maintaining the weight advantages of polymer materials in non-critical areas, resolving the contradiction between strength and weight.
Data Source
AI summary
A liftgate formed with a thermoplastic which is overmolded around preselected reinforcements at stress points, such as a corner area, which includes a pair of separate reinforcement plates and wherein a 3-dimensional reinforcement plate is connected between the pair of separate reinforcements. Preferably the 3-dimensional reinforcement plate is connected to three reinforcements.