Counter-Rotating Disc Mulching Mower Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mulching mower assemblies with single rotating blades face issues such as debris ejection, clogging, and tipping due to the weight and size of the blade, which poses safety risks and operational inefficiencies.
Innovation Solution
A counter-rotating mulching mower assembly with two disc cutters of approximately 30″ in diameter, mounted to rotate in opposite directions, is designed to direct debris internally, featuring cutting teeth on both surfaces and an anvil for further shredding, with arcuate inner walls and a guard fence to prevent ejection and clogging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a single large rotating blade (54" diameter) is used for mulching, then cutting capability is improved, but debris ejection and safety risks increase
Solution Approach 1:
The single large blade is segmented into two smaller counter-rotating blades (30" diameter each). This segmentation maintains cutting capability while reducing debris ejection, as the counter-rotating smaller blades contain debris more effectively than a single large blade
2Productivity
If a single large rotating blade (54" diameter) is used for mulching, then cutting capability is improved, but tipping risk increases due to weight and size
Solution Approach 1:
The single large blade is divided into two smaller counter-rotating blades. This segmentation reduces the weight and size of individual rotating components, thereby reducing the tipping moment and improving stability while maintaining overall cutting capability through the combined action of both blades
3Device complexity
If a single rotating blade is used for mulching, then simplicity of design is maintained, but clogging problems increase
Solution Approach 1:
The single blade design is segmented into two counter-rotating blades with opposite rotation directions. This creates opposing material flow patterns that prevent material accumulation and clogging, while the relatively simple counter-rotating mechanism maintains design feasibility
Solution Approach 2:
The blades rotate in opposite directions, creating inverted material flow patterns between the two blades. This inversion of rotation direction causes material to be pushed in opposite directions, preventing clogging by continuously clearing material from the cutting zone
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 counter-rotating design reduces the risk of debris ejection, minimizes clogging, and prevents tipping, ensuring safer and more efficient mulching operations by directing material internally for effective cutting and shredding.
Implementation Method 1
counter-rotation of the first disc cutter and the second disc cutter urging material at the inlet area to travel between the first and second disc cutters towards the outlet area within the mower housing
Data Source
AI summary
A mower assembly for cutting and mulching material. The mower assembly comprises a mower housing, a first disc cutter, a second disc cutter and an anvil. The first and second disc cutters are orientated such that their outer edges are spaced apart so that counter-rotation of the discs urges material to move between the discs from an inlet area toward an outlet area. Material travelling from the inlet area to the outlet area is subject to cutting and shredding by cutting teeth on the disc cutters. Material moving into the outlet area is subjected to further cutting and shredding through contact with the anvil.