Boat Propeller With Dampers For Impact Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional propellers face challenges in achieving easy assembly and disassembly while effectively buffering impact forces from obstacles, as the fitting accuracy between the hub and screw blades is difficult to determine to satisfy all conditions of easy maintenance and impact force reduction.
Innovation Solution
A propeller design featuring a shaft sleeve with individually supported blade components and dampers positioned between them, allowing for easy assembly and disassembly, and effective absorption of impact forces through the use of vibration-proof rubber dampers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high fitting accuracy is achieved between the hub and screw blades, then impact force buffering is improved, but assembly and disassembly become difficult
Solution Approach 1:
The propeller is divided into separable components: a hub and multiple screw blades that can be independently assembled and disassembled. The fitting portions are designed with specific geometric features (concave-convex structures, positioning protrusions) that enable easy connection and separation while maintaining reliable impact buffering when assembled.
Solution Approach 2:
Fitting portions with concave-convex structures and positioning protrusions act as intermediaries between the hub and screw blades. These intermediary structures provide precise alignment and secure connection during operation for impact buffering, while allowing straightforward insertion and removal during assembly and disassembly.
2Ease of operation
If easy assembly and disassembly are achieved, then maintainability is improved, but impact force buffering becomes unreliable
Solution Approach 1:
The fitting structure incorporates dynamic characteristics through clearance fits and positioning mechanisms that allow controlled movement during impact events. The screw blades can slightly shift relative to the hub during impact, absorbing shock while maintaining secure connection during normal operation, thus providing reliable buffering without compromising assembly ease.
Solution Approach 2:
The fitting portions are designed with specific dimensional parameters including clearance fits, positioning protrusion sizes, and concave-convex geometry ratios. These parameter optimizations enable the structure to transition between easy assembly mode and reliable impact buffering mode, achieving both objectives simultaneously.
3Reliability
If precise fitting accuracy is maintained, then impact force transmission to the hub is reduced, but assembly complexity increases
Solution Approach 1:
The fitting system is segmented into modular components with standardized interfaces. The hub contains multiple fitting portions with identical or similar geometric features, and each screw blade has corresponding fitting portions, creating a modular assembly system that reduces complexity while maintaining reliable impact force reduction.
Solution Approach 2:
The fitting portions are designed with universal geometric features (concave-convex structures, positioning protrusions) that serve multiple functions: alignment, connection, and impact force distribution. This multi-functionality reduces the need for complex specialized features while achieving reliable impact force reduction.
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 design enhances maintainability, reduces impact forces transmitted to the hub and output shaft, and ensures reliable performance even with less precise fitting accuracy, while maintaining high assembly and disassembly ease.
Implementation Method 1
a plurality of dampers disposed in a manner that each of the plurality of dampers is disposed between adjacent two of the plurality of blade components
Implementation Method 2
vibration-proof rubber dampers
Data Source
AI summary
To provide a propeller for a boat propulsion apparatus, which propeller is excellent in maintainability including easy assembly and easy disassembly and reliably reduces the impact force caused by colliding with an obstacle and transmitted to the hub and the output shaft of the boat propulsion apparatus. The propeller includes: a shaft sleeve insertably and removably fixed to an output shaft of the boat propulsion apparatus; a plurality of blade components that are individually supported by the shaft sleeve and are arranged at intervals in a rotation direction of the output shaft; and a plurality of dampers disposed in such a manner that each of the plurality of dampers is disposed between adjacent two of the plurality of blade components.