Weighted Bag Handle Assembly Stress Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic, shape-changing weightlifting devices experience unpredictable forces and non-uniform loading due to their flexible nature, and the coupling of handles to these devices often leads to deterioration, such as tears and rips, particularly at the stitching or joining areas.
Innovation Solution
A weighted bag design featuring a cylindrical shell with a circular cross-section, an inner bag, and a filling mechanism that includes a flexible funnel for easy filling and secure closure, along with a handle assembly that distributes forces evenly through strap configurations to reduce stress concentrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a handle is coupled to a flexible weightlifting bag, then the bag can be manipulated and lifted, but stress concentrations occur at the joining areas causing deterioration, tears and rips
Solution Approach 1:
The handle assembly is segmented into multiple components: the handle itself, strap portions that wrap around the bag, and a retention structure with channels. This segmentation distributes the coupling function across multiple elements rather than concentrating stress at a single joining point, thereby reducing stress concentrations on the stitching.
Solution Approach 2:
The coupling mechanism transitions from a two-dimensional stitched attachment to a three-dimensional wraparound configuration. The strap portions extend around the bag in circumferential directions and are retained by a retention structure, creating a volumetric distribution of forces that reduces stress on any single point of the bag material.
2Adaptability or versatility
If flexible material is used for the weightlifting bag, then the bag can change shape and be manipulated dynamically, but unpredictable forces and non-uniform loading occur
Solution Approach 1:
The bag is designed with a substantially cylindrical shape featuring curved surfaces. This geometric configuration naturally distributes applied forces more uniformly around the structure compared to angular shapes, reducing stress concentrations while maintaining the flexible, shape-changing properties of the material.
Solution Approach 2:
The bag utilizes a flexible shell construction that maintains its cylindrical form while allowing dynamic shape changes. The shell structure provides inherent force distribution characteristics that reduce unpredictable loading, even as the bag deforms during manipulation and exercise activities.
3Strength
If multiple strap portions are used to secure the handle, then force distribution is improved, but the device complexity increases
Solution Approach 1:
The retention structure serves multiple functions simultaneously: it retains the strap portions in position, provides channels for strap routing, and distributes forces across the bag surface. This multi-functionality reduces the need for separate components, thereby managing complexity while achieving improved force distribution.
Solution Approach 2:
Multiple functional elements are merged into integrated components. The retention structure combines strap retention, routing guidance, and force distribution functions. The strap portions themselves serve both as structural elements and as force-distributing members, reducing the overall component count despite the enhanced functionality.
Data Source
AI summary
A weighted bag having an outer shell and a handle assembly. The outer shell has a plurality of panels and at least one of one of a pair of slots and a first end loop assembly and a second end loop assembly spaced apart from the first end loop assembly coupled to the plurality of panels. The handle assembly has a handle grasping member and a strapping assembly, the strapping assembly extending from the handle grasping member and interfacing with at least one of the pair of slots and the first and second end loop assemblies so as to couple the handle assembly to the outer shell.