Dual-bearing reel coupling member weight reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dual-bearing reel coupling members struggle to balance weight reduction with maintaining sufficient strength, as increasing the diameter or number of through holes for weight reduction often compromises structural integrity.
Innovation Solution
A reel unit design featuring a thinned part with a box-like recessed shape on the inner surface of the coupling member, where the fishing rod attachment leg is fixed, and a cover member made of synthetic resin to further reduce weight and prevent galvanic corrosion, while maintaining strength through a thicker edge and pin-member passing holes for lightweight pin members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If through holes are increased in diameter or number for weight reduction, then weight of coupling member is reduced, but strength of coupling member deteriorates
Solution Approach 1:
The coupling member employs a thinned part with a recessed shape that creates a porous-like structure, reducing material density while maintaining structural integrity. This allows weight reduction without compromising strength, as the recessed design preserves critical load-bearing pathways while removing unnecessary material.
Solution Approach 2:
The coupling member features a thinned part located at a specific region where material can be removed without affecting overall strength. By applying local quality modification rather than uniform thinning, the design achieves weight reduction in non-critical areas while maintaining sufficient strength in load-bearing regions.
2Strength
If metal coupling member is used for strength, then strength is achieved, but weight increases and galvanic corrosion risk increases
Solution Approach 1:
The coupling member combines metal and synthetic resin materials to create a composite structure. The metal portions provide necessary strength and rigidity, while the synthetic resin portions reduce overall weight and prevent galvanic corrosion by acting as an electrical insulator between dissimilar metals.
Solution Approach 2:
The synthetic resin thinned part serves as a protective layer that can be replaced if needed, while the main metal structure retains its strength. This approach allows using lighter, corrosion-resistant material in non-critical areas.
3Weight of moving object
If through holes are bored for weight reduction, then weight is reduced, but bending strength degrades
Solution Approach 1:
The thinned part with recessed shape creates a controlled porous structure that reduces weight while maintaining bending strength. Unlike through holes that create stress concentration points, the recessed design maintains continuous material pathways that resist bending forces.
Solution Approach 2:
Instead of removing material in one dimension (through holes), the design uses a recessed shape that removes material in multiple dimensions, creating a three-dimensional weight reduction strategy that preserves structural integrity and bending strength.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present reel unit (1) is a reel unit for a dual-bearing reel (100) supporting a spool (12) in a rotatable state. The reel unit (1) includes a frame (5), a fishing rod attachment leg (10) and a thinned part (11). The frame (5) includes a first side plate (8), a second side plate (9) disposed in opposition to the first side plate (8) to enable the spool (12) to be disposed between the first side plate (8) and the second side plate (9), and a plurality of coupling members (14) integrally formed with the first side plate (8) and the second side plate (9) to couple the first side plate (8) and the second side plate (9). The fishing rod attachment leg (10) is fixed to an outer surface (15b) of one of the plurality of coupling members (14). The thinned part (11) has a box-like recessed shape and is formed on an inner surface (15a), faced to the spool (12), of the coupling member (14) to which the fishing rod attachment leg (10) is fixed. Furthermore, a dual-bearing reel comprising such a reel unit (1) and a method of manufacturing the such a reel unit (1) are also disclosed.