Fishing Reel Gear Mounting Structure Backlash Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing gear mounting structures in fishing reels experience backlash between the gear and worm shaft, leading to deterioration of rotational feel and noise due to a slight gap between the planar portion and slot portion.
Innovation Solution
A gear mounting structure that includes a worm shaft with intersecting spiral grooves and a gear locking portion with a non-circular cross section, combined with an elastic member that abuts the outer surface of the gear and worm shaft, providing resistance to backlash and improving rotational feel and noise reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If slots are formed in the worm shaft engaging a planar portion of the gear boss to connect them, then the gear and worm shaft can be connected, but backlash occurs due to gaps between the slots and planar portion leading to deterioration of rotational feel and noise
Solution Approach 1:
An elastic member is introduced as an intermediary element between the gear boss and worm shaft. This elastic member fills the gap between the slot and planar portion, eliminating backlash while maintaining the connection function. The elastic member deforms to accommodate the engagement while providing continuous contact pressure to prevent gaps.
Solution Approach 2:
The invention changes the physical state of the connection from rigid (slots and planar portions) to include elastic deformation. By introducing the elastic member, the connection parameters change to include continuous pressure and deformation capability, which eliminates the gaps that cause backlash while maintaining structural integrity.
2Object-generated harmful factors
If the gap between slots and planar portion is reduced, then backlash is reduced, but manufacturing precision requirements increase and assembly difficulty increases
Solution Approach 1:
The elastic member serves as a mediator that compensates for manufacturing tolerances. Instead of requiring precise gap control between the slot and planar portion, the elastic member absorbs dimensional variations and maintains consistent contact pressure, significantly reducing the impact of manufacturing precision variations on backlash.
Solution Approach 2:
The invention changes the approach from controlling geometric parameters (gap size) to controlling material properties (elasticity). By selecting appropriate elastic materials and dimensions, the system achieves consistent backlash elimination without requiring ultra-precise manufacturing of the slot and planar portion interfaces.
3Object-generated harmful factors
If an elastic member is added to abut the boss portion and gear locking portion, then backlash is suppressed and rotational feel is improved, but device complexity increases
Solution Approach 1:
The elastic member is designed to be retained within the existing structure rather than being a separate removable component. The elastic member fits into the slot structure and is held in place by the engagement geometry, effectively integrating it into the existing components and minimizing the increase in device complexity.
Solution Approach 2:
The elastic member functions as a flexible element that deforms to accommodate the engagement between the gear boss and worm shaft. This flexible approach replaces the need for complex rigid adjustment mechanisms, simplifying the overall structure while achieving backlash elimination through elastic deformation rather than mechanical adjustment.
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 solution effectively suppresses backlash between the gear and worm shaft, enhancing rotational feel and preventing noise, while maintaining a simple configuration and ensuring concentricity with an O-ring elastic member.
Implementation Method 1
an elastic member that abuts the outer surface of the boss portion of the gear, as well as at least a portion of the gear locking portion other than the engaged portion
Data Source
AI summary
A gear mounting structure includes a worm shaft, a gear, and an elastic member. The worm shaft includes a shaft body, on the outer surface of which is formed intersecting spiral grooves, and a gear locking portion with a non-circular cross section, on at least a portion of the outer surface of which is formed a curved surface portion and a planar portion. The gear includes a gear body, on the outer surface of which are formed teeth, and to which the handle rotation is transmitted, and a boss portion protruding from the gear body and having an engagement portion engaging the gear locking portion. The elastic member is mounted so as to abut the outer surface of the boss portion of the gear, and at least a portion of the curved surface portion of the gear locking portion.