Ball Joint Mounting Device for Grass Mower Cutting Units
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cutting unit mounting devices for grass mowing machines are expensive, complex, and time-consuming to assemble, with high parts counts, and they do not effectively minimize turf damage during mowing and transition between mowing and service positions.
Innovation Solution
A simplified cutting unit mounting device featuring a yoke with a pivotable ball joint and releasable lock pin that allows limited pivoting for mowing and restricted pivoting for service positions, reducing parts count and assembly time, and incorporating a strap with a lost motion slot to ensure the rear of the cutting unit hangs lower than the front during transport.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a traditional ball joint with tubular element is used, then the cutting unit can pivot on multiple axes, but the manufacturing complexity and assembly time increase significantly
Solution Approach 1:
The ball joint is divided into two separate parts: a spherical ball component and a spherical receptacle component. This segmentation eliminates the need for complex tubular element bending and welding operations, while still allowing the cutting unit to pivot on multiple axes through the ball-and-receptacle interface.
Solution Approach 2:
The spherical ball and receptacle are designed to fit together as a unified pivoting mechanism, combining the functions of multiple axes rotation and structural support into a single integrated assembly that reduces overall complexity compared to traditional tubular ball joints.
2Strength
If traditional ball joint manufacturing process is used, then the ball joint provides structural integrity, but the production time and cost increase
Solution Approach 1:
The spherical ball and receptacle are pre-formed as separate components with built-in alignment features and attachment mechanisms, eliminating the need for time-consuming on-site assembly operations such as drilling, pin insertion, and alignment adjustments.
Solution Approach 2:
The ball and receptacle components are designed with self-aligning features and self-securing mechanisms that automatically ensure proper positioning and structural integrity during assembly, eliminating the need for complex alignment procedures and specialized assembly tools.
3Ease of operation
If the cutting unit is raised to transport position, then the cutting unit can be transported, but turf damage may occur during lowering
Solution Approach 1:
The cutting unit mounting system incorporates dynamic control features that allow the cutting unit to be lowered in a controlled manner, maintaining contact with the ground surface and preventing damage during the transition from transport position to mowing position.
4Device complexity
If a simplified mounting device is used, then the cost and parts count are reduced, but the ability to secure cutting unit in service position may be compromised
Solution Approach 1:
The locking mechanism is extracted as a separate, simple component that can be independently engaged to secure the cutting unit in the service position, allowing the main mounting device to remain simple while adding reliability through the dedicated locking feature.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A cutting unit mounting device (10), comprising a lift arm (14), a cutting unit (12) attached to the lift arm (14) by means of a yoke (38), a ball (50) mounted to the yoke (38) and the ball (50) being pivotably mounted in a ball housing (53, 54) attached to the lift arm (14).