Disk Drive Suspension Load Beam with Constraint Layer Gap
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current disk drive suspensions face challenges in improving dynamics, particularly with stiff suspensions where dampers provide modest improvements, leading to increased settling times and potential off-track write errors due to resonant frequency excitation.
Innovation Solution
A disk drive suspension design incorporating a load beam with a constraint layer and adhesive layers, where the constraint layer acts as a damping layer to reduce vibrations, and the geometry of the load beam is optimized to tune resonant frequencies and damping effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a damper is applied to a stiff suspension, then suspension dynamics are improved, but the improvement is only modest and settling time increases
Solution Approach 1:
The patent applies local quality by creating a compliant region (gap) at a specific location in the suspension structure where the constraint layer is discontinuous. This localized compliance allows the suspension to flex more easily at the gap location, improving dynamics and reducing settle time without compromising the overall stiffness of the suspension structure.
Solution Approach 2:
The suspension uses a composite structure combining a rigid load beam with a compliant constraint layer made of viscoelastic material. This composite approach allows the rigid load beam to provide structural strength while the viscoelastic constraint layer provides damping and compliance, achieving both stiffness and improved dynamics simultaneously.
2Reliability
If a damper is applied to a stiff suspension, then suspension dynamics are improved, but off-track write errors may occur due to resonant frequency excitation
Solution Approach 1:
The patent changes the physical parameters of the suspension by introducing a gap in the constraint layer, which alters the resonant frequency characteristics and damping properties. This parameter change allows the suspension to avoid resonant excitation at critical frequencies, preventing off-track write errors while maintaining improved dynamics.
Solution Approach 2:
The patent converts the potentially harmful effect of resonant frequency excitation into a benefit by strategically positioning the gap to shift resonant frequencies away from problematic ranges. The gap structure transforms the suspension's natural resonance into a beneficial damping characteristic that prevents off-track errors.
3Manufacturing precision
If the suspension is made stiffer to improve structural integrity, then manufacturing precision is maintained, but settling time increases and dynamics worsen
Solution Approach 1:
The suspension structure maintains high stiffness in the load beam for structural integrity while introducing a localized gap in the constraint layer to provide compliance. This local quality differentiation allows the majority of the structure to remain stiff for precision manufacturing while the gap provides the necessary flexibility to reduce settling time.
Solution Approach 2:
The constraint layer is segmented into discrete sections with a gap between them, rather than being continuous. This segmentation allows the suspension to have rigid sections for structural integrity while the gap provides compliance, achieving both manufacturing precision and improved dynamics.
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 optimized suspension design enhances disk drive dynamics, reducing settling times and minimizing off-track errors by effectively damping vibrations and improving servo bandwidth.
Implementation Method 1
the constraint layer acts as a damping layer to reduce vibrations
Implementation Method 2
the constraint layer acts as a damping layer to reduce vibrations
Implementation Method 3
adhesive layers, where the constraint layer acts as a damping layer
Data Source
AI summary
A method of manufacturing a suspension for a disk drive includes providing and assembling an actuator coupling plate, a bend region, a load beam, and a head receiving gimbal. The load beam has a first end and a second end and defines a longitudinal axis that bisects the first end and the second end. The load beam is coupled to the gimbal proximate the first end and includes a base region proximate the second end, the base region having a first lateral section to one side of the longitudinal axis and a second lateral section to another side of the longitudinal axis. The first and the second lateral sections define a gap therebetween, and the base region has a bridge extending across the gap. A constraint layer overlays the gap and the bridge.