Robot Joint Structure Dual Seal Pressure Differential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing joint structures in robots and mechanical components face challenges in maintaining a sealed state against external pressures and preventing the ingress of dust and water droplets, leading to potential damage and leakage of lubricants.
Innovation Solution
A joint structure featuring two seal members with a pressure-applying mechanism that increases air pressure between them, where the outer seal member has lower pressure resistance than the inner seal member, and optionally includes a protection wall and cut portions for enhanced sealing and ease of replacement, effectively preventing foreign matter entry and maintaining the integrity of mechanical components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single seal member is used to seal the gap between joint members, then the structure is simple, but the sealing performance against external pressure is insufficient
Solution Approach 1:
The seal member is divided into two distinct parts: an inner seal member with high pressure resistance for sealing the lubricant storing part, and an outer seal member with lower pressure resistance for sealing the space between joint members. This segmentation allows each seal member to be optimized for its specific function, improving overall sealing performance while maintaining reasonable structural complexity.
Solution Approach 2:
Different regions of the sealing system are assigned different properties: the inner seal member is designed with high pressure resistance to withstand lubricant pressure, while the outer seal member is designed with lower pressure resistance and elastic material properties to effectively seal against external pressure and allow easy replacement. This local differentiation of properties optimizes the sealing performance for each specific requirement.
2Adaptability or versatility
If the outer seal member is made of elastic material with cut portions, then the sealing adaptability is improved, but the structural strength is reduced
Solution Approach 1:
The outer seal member is constructed from elastic material that can flexibly adapt to the gap between joint members, providing effective sealing even when the gap varies. The material's elasticity allows it to conform to surface irregularities and maintain sealing contact under varying operating conditions.
Solution Approach 2:
The outer seal member is divided by cut portions into multiple arc-shaped segments. This segmentation reduces the overall structural strength requirement while maintaining sealing effectiveness, as each segment can independently deform to seal the gap. The cut portions also facilitate easy installation and replacement of the seal member.
3Reliability
If the outer seal member has lower pressure resistance than the inner seal member, then the sealed state is better protected, but the pressure resistance of the outer seal is reduced
Solution Approach 1:
The pressure resistance property is locally differentiated between the two seal members. The inner seal member is designed with high pressure resistance to contain the lubricant storing part, while the outer seal member is designed with lower pressure resistance to effectively seal against external pressure without requiring excessive strength. This local property differentiation optimizes the overall system performance.
Solution Approach 2:
The outer seal member acts as a protective barrier that absorbs and cushions external pressure and foreign matter before they can reach the inner seal member. By positioning the lower pressure resistance seal member on the outer side, it provides beforehand protection to the more critical inner sealing interface, preventing direct exposure to harsh external conditions.
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 significantly enhances sealing performance against external pressures, reliably maintains the sealed state, and allows for easy detection of seal deterioration through gas flow rate measurements, ensuring the longevity and reliability of mechanical components.
Implementation Method 1
a pressure-applying means that makes the air pressure in a space provided between the two seal members higher than the pressure of the outside air
Implementation Method 2
the seal member on the outer side may be formed of an elastic material and may have a cut portion at at least one circumferential position
Data Source
AI summary
An object is to exhibit a higher sealing performance against an external pressure, to more reliably prevent breakage of a sealed state established by an inner seal member, and to maintain the soundness of inner mechanical components. Provided is a joint structure including two joint members, a driving mechanism that rotationally drives the two joint members about a predetermined axis relative to each other, two seal members forming a seal between the joint members at positions doubly surrounding the outside of a lubricant storing part in the driving mechanism, and a pressure-applying means that makes the air pressure in a space provided between the two seal members, higher than the pressure of the outside air.