DSA Suspension Microactuators Flexible Connectors Gimbal

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Dual stage actuator (DSA) suspensions in disk drives face challenges with low servo bandwidth due to resonances, increased mass affecting dynamic performance, and manufacturing issues in existing designs, particularly when microactuators are located on the gimbal or require complex routing and additional components.

Innovation Solution

The DSA suspension design features piezoelectric (PZT) microactuators extending from a non-gimbaled load beam to a gimbaled portion via flexible stainless steel connectors, allowing for pitch and roll movement without interfering with gimbal action, and using single-layer bulk PZTs for increased stroke length and shock resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If microactuators are located on the gimbal or require complex routing, then fine control of the slider is improved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:

Improvefine control of sliderVSAvoidcomplex routing and additional components

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The microactuators are extracted from the gimbal region and relocated to the load beam, separating the fine control function from the gimbal assembly. This reduces device complexity while maintaining fine control capability through the flexible connector linkage.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

A flexible connector is introduced as an intermediary element between the microactuator on the load beam and the gimbal assembly. This mediator transmits the fine control forces while accommodating the gimbal's pitch and roll movements, enabling fine control without direct microactuator mounting on the gimbal.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Force

If rigid connectors are used to connect microactuators to the gimbal, then force transmission is improved, but gimbal freedom of movement is restricted

Engineering Contradiction:

Improveforce transmissionVSAvoidgimbal freedom of movement

Core Design Contradiction:

ForceVSEase of operation

Solution Approach 1:

A flexible connector with ribbon-like geometry is used to connect the microactuator to the gimbal assembly. This flexible structure provides sufficient force transmission while accommodating the pitch and roll movements of the gimbal, maintaining both force transmission and operational freedom.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The connector transitions from a rigid static structure to a flexible dynamic structure that can adapt its configuration. The flexible connector dynamically adjusts to the gimbal's movements while maintaining force transmission, enabling both strong coupling and freedom of movement.

Inventive Principle:

Principle #15Dynamics

3Manufacturing precision

If multi-layer or thin-film PZTs are used, then manufacturing precision is improved, but cost and device complexity increase

Engineering Contradiction:

ImprovePZT fabrication accuracyVSAvoidPZT structure complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent employs simple single-layer bulk PZT materials rather than complex multi-layer or thin-film PZT structures. This approach uses readily available, easier-to-manufacture materials that achieve the required performance without the complexity and cost of advanced PZT fabrication techniques.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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 design achieves high servo bandwidth, improved shock susceptibility, and reduced fretting wear by allowing the gimbal to pitch and roll freely while maintaining efficient push/pull movement, using less expensive single-layer bulk PZTs and minimizing transverse forces on the slider tongue.

Implementation Method 1

at least one piezoelectric (PZT) microactuator extending from a non-gimbaled load beam to a gimbaled portion

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

flexible connectors that are strong enough in compression so as to not significantly buckle... and that are flexible enough so as to not significantly interfere with the gimballing action

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS9129624B1DSA suspension with microactuators extending to gimbal through flexible connectors

Publication Date: 2015.09.08 MAGNECOMP CORP

AI summary

A dual stage actuated (DSA) suspension includes two PZT microactuators that are attached at their first ends to a non-gimbaled portion of the suspension such as the portion of the flexure that is rigidly attached to the load beam, and are attached at their second ends to the gimbaled portion of the suspension such as the gimbal tongue through flexible connectors that can be formed integrally with the suspension's flexure. The flexible connectors are flexible enough so as not to interfere with the suspension's gimballing action. The flexible connectors transmit force from the PZTs to the gimbal as the PZTs expand and contract in order to rotate the gimbal and thus effect fine movements of the head slider.