Rotary Damper Seal Rings Mitigating Shaft Misalignment Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dampers for viscous fluids face issues with fluid leakage due to misalignment of the resistance generating member, which causes unstable seal tightness and potential fluid leakage.
Innovation Solution
The use of annular elastic members with specific width profiles for the inner and outer peripheral surfaces between the fluid holding chamber and the resistance generating member, reducing contact area changes and enhancing seal stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an O-ring made of elastic body is arranged between the fluid holding chamber and the resistance generating member to prevent leakage, then the seal function is improved, but the external force deforms the O-ring elastically causing shaft misalignment and unstable seal tightness
Solution Approach 1:
The seal member is divided into multiple segments (first seal member and second seal member) that can independently deform and adapt to misalignment, preventing the entire seal from failing due to shaft deviation while maintaining sealing effectiveness
Solution Approach 2:
The seal member's cross-sectional shape is changed from circular to a shape with different width in axial and radial directions, allowing differential deformation characteristics that accommodate shaft misalignment while maintaining stable seal tightness
2Device complexity
If a circular cross-section O-ring is used for sealing, then the seal structure is simple, but the contact area changes with radial deformation causing unstable seal tightness
Solution Approach 1:
The seal member has different width dimensions in different directions (wider in axial direction, narrower in radial direction) to provide different contact characteristics and deformation behaviors in different orientations, improving seal stability under misalignment conditions
Solution Approach 2:
The seal member's cross-section is designed with asymmetric width distribution, creating different contact areas with the fluid holding chamber and resistance generating member that remain stable even when radial deformation occurs due to misalignment
3Adaptability or versatility
If the O-ring deforms elastically in radial direction due to misalignment, then the seal adapts to the gap, but the contact area changes causing unstable seal tightness and potential leakage
Solution Approach 1:
The seal member is designed to dynamically adjust its contact area distribution through controlled deformation in different directions, maintaining stable sealing pressure even when adapting to gaps caused by shaft misalignment
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
This configuration significantly reduces the likelihood of fluid leakage by maintaining stable seal tightness and allowing smooth sliding, thereby extending the life cycle of the seal rings.
Implementation Method 1
even if misalignment of the resistance generating member happens to deform the elastic member elastically in a radial direction, it is possible to reduce any changes in a contact area between the elastic member and each of the fluid holding chamber and the resistance generating member
Implementation Method 2
the viscous fluid in this area passes through the flow path formed on the fixed vane and moves to the area located downstream in the rotor rotation direction from the fixed vane of the inner chamber. At this time, the damping torque generates depending on a resistance by the motion of the viscous fluid
Data Source
Figure 1(A)~1(C)
Figure 2(A)~2(B)
Figure 3(A)~3(B)
AI summary
Provided is a damper wherein viscous fluid which fills a circular cylinder chamber is more reliably prevented from leaking. A rotary damper (1) includes: a first seal ring (8a) of an elastic body, arranged between a through-hole (23) of a circular cylinder chamber (21) in a case (2) and a lower end of a rotor body of a rotor (3); and a second seal ring (8b) of an elastic body, arranged between a through-hole (60) in a lid (6) and an upper end of the rotor body. The first seal ring (8a) has: an outer peripheral surface with a width in a direction of a center axis of the circular cylinder chamber (21), which is pressed against an inner peripheral surface of the through-hole (23); and an inner peripheral surface with a width in the direction of the center axis of the circular cylinder chamber (21), which is pressed against an outer peripheral surface of the lower end of the rotor body, and also a second seal ring (8b) has: an outer peripheral surface with a width in the direction of the center axis of the circular cylinder chamber (21), which is pressed against an inner peripheral surface of the through-hole (60); and an inner peripheral surface with a width in the direction of the center axis of the circular cylinder chamber (21), which pressed against an outer peripheral surface of the upper end of the rotor body.