Hard Drive Disc Pack Couple Imbalance Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hard drives experience performance issues due to couple imbalance caused by disc pack positioning and biasing, leading to noise, vibration, and misalignment errors during data reading and writing, which existing technologies have not adequately addressed.
Innovation Solution
The discs in a hard disk drive are strategically biased in alternating directions to minimize couple imbalance by modifying the disc biasing pattern, using a combination of discs biased in one direction and others in a second direction, thereby optimizing the disc pack's configuration to reduce overall imbalance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If discs are biased in a single direction on the hub, then the disc pack structure is simple and easy to manufacture, but couple imbalance occurs causing noise, vibration, and misalignment errors
Solution Approach 1:
The patent applies asymmetry by biasing discs in alternating directions (first direction and second direction) rather than uniform single-direction biasing. This asymmetric arrangement of biasing forces creates balance in the alternating pattern, reducing couple imbalance while maintaining manufacturing feasibility through systematic alternation of biasing directions across multiple discs
Solution Approach 2:
The patent uses counterweight principles by introducing discs biased in the opposite direction to counterbalance the imbalance generated by discs biased in the first direction. Each disc biased in one direction creates an imbalance that is compensated by subsequent discs biased in the opposite direction, effectively canceling out the harmful couple imbalance forces
2Object-generated harmful factors
If discs are biased in alternating directions to reduce couple imbalance, then noise and vibration are reduced, but the disc pack configuration becomes more complex
Solution Approach 1:
The patent segments the disc pack into groups of discs with alternating biasing directions. Rather than treating the disc pack as a uniform structure, it divides the discs into sequential segments where each segment alternates biasing direction, creating a modular pattern that reduces complexity compared to customizing each disc individually while achieving the balance needed to reduce noise and vibration
3Ease of manufacture
If traditional disc biasing is used, then manufacturing is straightforward, but misalignment errors occur during data reading and writing
Solution Approach 1:
The patent implements periodic action through the alternating pattern of disc biasing directions. This periodic alternation creates a regular, repeating sequence of force directions that maintains consistent spacing and alignment across all discs, reducing misalignment errors during operation while preserving manufacturing simplicity through the systematic periodic pattern
Data Source
AI summary
In certain embodiments, an apparatus includes a basedeck; a motor coupled to the basedeck and having a rotatable hub; and first, second, third, fourth, and fifth discs coupled to the hub. Three of the five discs are biased against the hub in a first direction and two of the five discs are biased against the hub in a second direction. In certain embodiments, a method includes biasing at least three discs against a hub in a first direction and biasing at least two discs against the hub in a second direction.