IN-PIVOT HYBRID STEPPER MOTOR FOR BALL SCREW CAM ELEVATOR MECHANISM FOR REDUCED-HEAD HARD DISK DRIVE

An approach to a reduced-head hard disk drive (HDD) involves an actuator elevator subsystem that includes a ball screw cam assembly with a hybrid permanent magnet (PM)-variable reluctance (VR) stepper motor disposed therein, to rotate the cam screw, which vertically translates an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack. A suitably configured hybrid stepper motor can provide 200 full steps/rev for a 3.8 mm translation. Thus, to meet or surpass a step resolution of 6 μm/μstep or 0.5625°/μstep, the hybrid stepper motor would only need to be operated at 4 micro-step mode in order to achieve a 0.45°/μstep or 0.00475 mm/μstep, which enables a smoother motion since the available holding torque at the 4micro-step provides sufficient torque margin to overcome load torque, frictional torque, and detent torque. 1. An actuator system for a reduced-head hard disk drive (HDD) , the system comprising:a ball screw cam assembly;a head-stack assembly (HSA) translatably coupled with the cam assembly;a permanent magnet (PM)-variable reluctance (VR) hybrid stepper motor disposed within and affixed to a screw of the cam assembly, and configured to drive rotation of the screw to drive translation of the HSA along an axis of the screw; anda fixed shaft around which the stepper motor is positioned; a plurality of ring-shaped permanent magnets (PMs),', 'a stack of electrical steel lamination rings interposed between each adjacent pair of the PMs,', 'wherein the PMs and the lamination rings are affixed to an inner diameter of the screw and collectively operate as a rotor of the hybrid stepper motor,', 'a stator, disposed within the rotor, comprising a stack of electrical steel laminations configured with a plurality of main poles each having a plurality of teeth, and', 'a coil wound on each of the main poles., 'wherein the hybrid stepper motor is rotatable about the fixed shaft to drive the ...

Axial flux permanent magnet motor for ball screw cam elevator mechanism for reduced-head hard disk drive

An approach to a reduced-head hard disk drive (HDD) involves an actuator elevator subsystem that includes a ball screw cam assembly with an axial flux permanent magnet (AFPM) motor affixed to a cam screw to drive rotation of the screw, which drives translation of an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack.

In-Pivot Stepper Motor For Ball Screw Cam Elevator Mechanism For Cold Storage Data Storage Device

An approach to a reduced-head hard disk drive (HDD) involves an actuator subsystem that includes a ball screw cam assembly wherein the number of starts of a multi-start screw equals the number of balls riding in a corresponding start. A stepper motor may be disposed within the screw, to drive rotation of the screw, which drives translation of an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack. The actuator subsystem may further include a cam locking mechanism for coupling and decoupling the actuator arm with a coil support structure and corresponding voice coil, so that the cam mechanism is able to move under the control of a voice coil motor when input/output operations are performed and is able to move the actuator arm assembly during translation operations. 1. An actuator system for a reduced-head hard disk drive (HDD) , the system comprising:a ball screw cam assembly;a head-stack assembly (HSA) translatably coupled with the cam assembly;a stepper motor disposed within and affixed to a screw of the cam assembly, and configured to drive rotation of the screw to drive translation of the HSA along an axis of the screw.2. The actuator system of claim 1 , wherein the stepper motor comprises a multi-phase claw-pole stepper motor.3. The actuator system of claim 1 , further comprising:a fixed shaft around which the stepper motor is positioned; and a hollow tubular permanent magnet,', 'at least one circular coil disposed within the tubular permanent magnet, and', 'at least one pair of mated claw-pole structures disposed within the tubular permanent magnet and in which at least one coil is disposed., 'wherein the stepper motor is rotatable about the fixed shaft, the stepper motor comprising4. The actuator system of claim 3 , wherein the stepper motor comprises:two circular coils disposed within the tubular permanent magnet in a stacked formation; anda pair of mated claw-pole ...

Piezoelectric-based locking of actuator elevator mechanism for cold storage data storage device

An approach to a reduced-head hard disk drive (HDD) involves an actuator elevator assembly for moving an actuator assembly along at least one support feature to provide a head slider access to at least two different disk media of a disk stack. The HDD includes a piezoelectric-based locking mechanism, including at least one piezoelectric actuator, movably coupled with the support feature, such that actuation of the actuator either locks or unlocks the locking mechanism relative to the support feature. When unlocked, the actuator assembly can be translated along the length of the disk stack via the actuator elevator assembly.

Piezoelectric-based locking of actuator elevator mechanism for cold storage data storage device

An approach to a reduced-head hard disk drive (HDD) involves an actuator elevator assembly for moving an actuator assembly along at least one support feature to provide a head slider access to at least two different disk media of a disk stack. The HDD includes a piezoelectric-based locking mechanism, including at least one piezoelectric actuator, movably coupled with the support feature, such that actuation of the actuator either locks or unlocks the locking mechanism relative to the support feature. When unlocked, the actuator assembly can be translated along the length of the disk stack via the actuator elevator assembly.

Axial flux permanent magnet motor for ball screw cam elevator mechanism for reduced-head hard disk drive

An approach to a reduced-head hard disk drive (HDD) involves an actuator elevator subsystem that includes a ball screw cam assembly with an axial flux permanent magnet (AFPM) motor affixed to a cam screw to drive rotation of the screw, which drives translation of an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack.

In-pivot stepper motor for ball screw cam elevator mechanism for cold storage data storage device

An approach to a reduced-head hard disk drive (HDD) involves an actuator subsystem that includes a ball screw cam assembly wherein the number of starts of a multi-start screw equals the number of balls riding in a corresponding start. A stepper motor may be disposed within the screw, to drive rotation of the screw, which drives translation of an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack. The actuator subsystem may further include a cam locking mechanism for coupling and decoupling the actuator arm with a coil support structure and corresponding voice coil, so that the cam mechanism is able to move under the control of a voice coil motor when input/output operations are performed and is able to move the actuator arm assembly during translation operations.

In-pivot stepper motor for ball screw cam elevator mechanism for cold storage data storage device

In-pivot stepper motor for ball screw cam elevator mechanism for cold storage data storage device

An approach to a reduced-head hard disk drive (HDD) involves an actuator subsystem that includes a ball screw cam assembly wherein the number of starts of a multi-start screw equals the number of balls riding in a corresponding start. A stepper motor may be disposed within the screw, to drive rotation of the screw, which drives translation of an actuator arm assembly so that a corresponding pair of read-write heads can access different magnetic-recording disks of a multiple-disk stack. The actuator subsystem may further include a cam locking mechanism for coupling and decoupling the actuator arm with a coil support structure and corresponding voice coil, so that the cam mechanism is able to move under the control of a voice coil motor when input/output operations are performed and is able to move the actuator arm assembly during translation operations.