Parallel Damper System for Orthopedic Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current damper systems for orthopedic devices, particularly for joint devices of the lower extremities, lack the ability to adapt damping behavior effectively to different use scenarios and ensure high reliability, with speed-dependent hysteresis behavior and potential failure points in hydraulic or pneumatic systems.
Innovation Solution
A damper system featuring a second, speed-independent damper device acting in parallel with the primary damper, providing adjustable damping properties through a structural or elastomeric damper with a tubular design, which can surround the primary damper for enhanced reliability and safety, and a switching mechanism to alter damping effects based on movement direction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a hydraulic or pneumatic damper device is used to influence relative movements, then damping control is achieved through fluid transport, but the system exhibits speed-dependent hysteresis behavior and has potential failure points
Solution Approach 1:
The damper system is divided into two independent damper devices: a first hydraulic/pneumatic damper and a second structural/elastomeric damper. Each damper can function independently, so if one fails, the other continues to provide damping. This segmentation increases reliability while maintaining adaptability through the combination of different damping mechanisms.
Solution Approach 2:
The system combines two different types of damping materials/mechanisms: hydraulic/pneumatic fluid damping and structural/elastomeric material damping. This composite approach allows the system to leverage the advantages of both: the adjustability of fluid damping and the speed-independent behavior of elastomeric damping, while improving overall reliability.
2Adaptability or versatility
If a single damper device is used, then the device complexity is low, but the adaptability to different movement phases and damping characteristics is limited
Solution Approach 1:
Two different damper devices are merged into a single damper system that operates in parallel. The first hydraulic/pneumatic damper and the second structural/elastomeric damper work together to provide a comprehensive damping solution with adjustable characteristics, achieving high adaptability while keeping the overall structure relatively compact.
Solution Approach 2:
The combined damper system serves multiple functions: it provides speed-dependent damping control through the hydraulic/pneumatic damper, speed-independent damping through the structural/elastomeric damper, and can be configured for different movement phases. This multi-functionality achieves high adaptability without requiring multiple separate systems.
3Adaptability or versatility
If hydraulic or pneumatic damping is used with adjustable flow cross-section, then damping range is wide and adaptable, but the probability of failure increases due to moving components
Solution Approach 1:
The second structural/elastomeric damper acts as a backup damping mechanism that is always ready to function. If the hydraulic/pneumatic damper fails due to component issues, the elastomeric damper immediately provides the necessary damping without requiring any active control or additional components. This beforehand cushioning ensures continuous reliable operation.
Solution Approach 2:
The structural/elastomeric damper can be designed as a simpler, more reliable component with fewer moving parts compared to the hydraulic/pneumatic damper. While individual elastomeric dampers may have limited service life, their simplicity and reliability make them ideal backup components that can be easily replaced if needed, reducing the overall failure probability of the system.
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
Enables adaptable damping behavior for different movement phases, ensures reliable operation even if the primary damper fails, and provides a compact, efficient design with adjustable damping characteristics, enhancing the safety and effectiveness of orthopedic devices.
Implementation Method 1
Hydraulic or pneumatic damping is typically achieved through controlled fluid transport from a flexion or extension chamber
Implementation Method 2
In pneumatic systems, damping can be achieved through compression and/or controlled release from the respective chamber
Implementation Method 3
The second damper device can be designed as a speed-independent damper, in particular as a friction damper
Implementation Method 4
The second damper device is designed as a structural damper made of an elastomer
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Damper system for orthopaedic devices, with a proximal fastening device (10) and a distal fastening device (20) which are coupled to each other in such a way as to be displaceable relative to each other, with a first hydraulic or pneumatic damper device (30), which is arranged between the fastening devices (10, 20) and has a flexion chamber (31) and an extension chamber (32) separated from each other by a movable piston (33) and connected fluidically to each other by at least one overflow line (34), wherein a second damper device (40) with a parallel action, and with a velocity-independent hysteresis behaviour, is arranged between the fastening devices (10, 20) and is configured as a tube structure damper.