Harmonic Drive Diaphragm Venting for Seal and Bearing Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing harmonic drives face challenges in maintaining the service life of consumable parts due to pressure and temperature fluctuations during torque transmission, which can lead to stress on seals and bearings.
Innovation Solution
Incorporation of a diaphragm system that equalizes gas pressure and temperature differences within the harmonic drive, using a diaphragm made of aluminum ceramic with micropores to prevent the ingress or egress of substances and manage thermal stress, while separating the interior from the external environment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the harmonic drive operates under torque transmission, then torque is transmitted through tooth engagement, but pressure and temperature fluctuations occur that stress seals and bearings
Solution Approach 1:
A diaphragm is introduced as an intermediary component between the internal drive environment and the external surroundings. The diaphragm equalizes pressure and temperature fluctuations caused by torque transmission, protecting seals and bearings from stress while allowing controlled thermal and pressure compensation. This mediator absorbs the harmful fluctuations without compromising torque transmission capability.
Solution Approach 2:
The patent employs parameter changes by allowing controlled variations in pressure and temperature within the harmonic drive through the diaphragm mechanism. The diaphragm enables the system to adapt to pressure and temperature changes during operation, transforming rigid constraints into flexible parameters that can equalize fluctuations, thereby reducing stress on consumable parts while maintaining operational effectiveness.
2Reliability
If the interior of the harmonic drive is sealed to protect components, then protection is provided, but pressure and temperature equalization with the surroundings is prevented
Solution Approach 1:
The diaphragm is implemented as a flexible thin film that selectively separates the internal drive environment from external surroundings. This flexible barrier allows pressure and temperature equalization through its material properties while maintaining physical separation that protects internal components from contaminants. The diaphragm's flexibility enables it to accommodate pressure differentials while permitting thermal and pressure equilibrium.
Solution Approach 2:
The diaphragm utilizes porous material structure with controlled micropores that permit gas molecules to pass through for pressure and temperature equalization while blocking larger liquid and solid particles. This porous configuration enables selective permeability - allowing thermal and pressure compensation while maintaining protective sealing against contaminants, thus resolving the contradiction between sealing and equalization.
3Temperature
If a diaphragm with micropores is used to equalize pressure and temperature, then equalization is achieved, but the diaphragm must prevent ingress or egress of substances
Solution Approach 1:
The diaphragm is constructed from porous material with specifically controlled micropore sizes that exploit size-based filtration. The micropores are dimensioned to permit passage of gas molecules necessary for pressure and temperature equalization while being sufficiently small to block larger liquid droplets and solid particulates. This creates a natural filtration mechanism that achieves equalization while preventing harmful substance transfer.
Solution Approach 2:
The diaphragm exhibits local quality through its microporous structure, where different regions at the micro-scale have different permeability characteristics. Gas molecules can pass through the micropores for equalization, while the same structure locally blocks larger substances. This local differentiation in permeability properties allows simultaneous achievement of temperature equalization and substance prevention.
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
Enhances the durability of seals and bearings by managing internal pressure and temperature fluctuations, thereby extending the service life of the harmonic drive components.
Implementation Method 1
a diaphragm (16) arranged at said opening (15) in order to equalize gas pressure between an interior (17) of the harmonic drive (21) and external surroundings (18) of the harmonic drive (21)
Implementation Method 2
a diaphragm (16) arranged at said opening (15) in order to equalize gas pressure and/or temperature differences between an interior (17) of the harmonic drive (21) and external surroundings (18) of the harmonic drive (21)
Implementation Method 3
using a diaphragm made of aluminum ceramic with micropores to prevent the ingress or egress of substances
Data Source
AI summary
A harmonic drive is disclosed that includes a flexible ring element, which can be deformed in a locally radial manner in the circumferential direction by a wave generator with a non-round outer peripheral surface and which includes an outer toothing, and a rigid ring element with an inner toothing. The outer toothing of the flexible ring element at least partly meshes with the inner toothing of the rigid ring element in order to transmit a torque at at least one tooth engagement region, wherein the wave generator has a non-round first inner ring which protrudes at least partly into the flexible ring element and is rotationally fixed to a shaft. The harmonic drive additionally comprises a first bearing element, comprising a second inner ring and at least one first outer ring, said second inner ring being secured to the rigid ring element. Each outer ring is secured to the flexible ring element. Additionally, a drive cover is provided which is secured to a substantially radially extending section of the flexible ring element, and the drive cover is equipped with at least one opening on which a diaphragm is arranged in order to equalize gas pressure and/or temperature differences between the interior of the harmonic drive and the surroundings of the harmonic drive.