Robotic Lawnmower Bellows Assembly for Sealed Shell Suspension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Robotic lawnmowers face challenges with complex and expensive suspension arrangements that are not weatherproof, which complicates assembly and increases the risk of errors and dirt/moisture resistance issues.
Innovation Solution
A robotic lawnmower with a shell suspension arrangement featuring a flexible bellows element integrally formed with a mounting substrate of different materials, using thermoplastic vulcanizate and thermoplastic, which facilitates assembly, reduces error risk, and enhances dirt and moisture resistance, while incorporating a collision and/or lift sensing arrangement for movement detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a complex suspension arrangement is used to enable movement detection between the outer shell and chassis, then the robotic lawnmower can detect collision and lift events, but the assembly process becomes more complex and error-prone
Solution Approach 1:
The patent combines the bellows element and mounting substrate into a single integrally formed component. The bellows element is molded directly onto the mounting substrate in a two-shot injection molding process, eliminating separate assembly steps and reducing the risk of assembly errors while maintaining the suspension arrangement's movement detection functionality
Solution Approach 2:
The integrally formed bellows element serves multiple functions simultaneously: it provides sealing between the outer shell and chassis, allows for relative movement detection, and integrates the mounting substrate for secure attachment. This multi-functionality reduces the need for separate components and simplifies the overall assembly process
2Reliability
If traditional suspension arrangements are used, then the robotic lawnmower can achieve basic suspension functionality, but the sealing performance against dirt and moisture is insufficient
Solution Approach 1:
The patent employs a flexible bellows element made of thermoplastic elastomer that acts as a sealing barrier between the outer shell and chassis. This flexible membrane allows relative movement while maintaining effective sealing against dirt and moisture, protecting the internal components from environmental contaminants
Solution Approach 2:
The bellows element is constructed using composite materials - specifically thermoplastic elastomer for the flexible sealing portion and thermoplastic for the rigid mounting substrate. This material combination provides both the necessary flexibility for sealing and movement, and the structural integrity for durable attachment to the chassis
3Ease of manufacture
If separate bellows element and mounting substrate are used, then component manufacturing is simplified, but assembly time increases and assembly errors may occur
Solution Approach 1:
The bellows element and mounting substrate are merged into a single integrally formed component through two-shot injection molding. This eliminates the need for separate assembly of these parts, reducing assembly time and eliminating potential assembly errors while maintaining the manufacturing advantages of molded components
4Reliability
If the bellows element is made of soft material for sealing, then sealing performance improves, but the structural strength and durability decrease
Solution Approach 1:
The patent uses composite materials to resolve the strength-sealing contradiction. The thermoplastic elastomer portion provides soft sealing contact with high sealing performance, while the thermoplastic mounting substrate provides structural strength and rigidity for durable attachment. The integral formation ensures strong bonding between the two materials
Solution Approach 2:
Different regions of the bellows element have different material properties optimized for their specific functions. The bellows portion is made of soft thermoplastic elastomer for sealing, while the mounting substrate is made of hard thermoplastic for structural support. This local differentiation of material quality allows each region to perform its intended function optimally
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 provides a robust, durable, and weatherproof suspension system with improved assembly ease and resistance to dirt and moisture, enabling effective movement detection and extended lifespan through high sealing performance and elastic recovery.
Implementation Method 1
a flexible bellows of a first, relatively softer material integrally formed with a mounting substrate of a second, relatively harder material
Implementation Method 2
the thermoplastic elastomer may be thermoplastic vulcanizate. Thereby, a high sealing performance, in combination with a high elastic recovery and a high degree of resistance against flex fatigue, may be obtained
Data Source
Figure 1~2
Figure 3A~3B
Figure 4
AI summary
A robotic lawnmower comprises a chassis, an outer shell defining an exterior face of the robotic lawnmower, and a shell suspension arrangement movably connecting the outer shell to the chassis, the shell suspension arrangement comprising at least one shell support lever assembly comprising a shell support lever movably arranged relative to the chassis, and a bellows element (34) sealing between the shell support lever and the chassis. The bellows element (34) comprises a flexible bellows (36) of thermoplastic vulcanizate integrally formed with a rigid mounting substrate (38) of thermoplastic.