Seagate Technology Incorporated

Other

Michael John Raffetto

Frederick Frank Kazmierczak

Klaus Dieter Kloeppel

John C Dunfield

Michael A Maiers

Robert Michael Pelstring

Donald J MacLeod

Michael Kenneth Andrews

Clifford T Jue

Andrew John Hudson

Roy Lynn Wood

Bradley David Kelemen

Chul Soo Kim

Fredrick Frank Kazmierczak

A disc mounting system for mounting the discs of a disc drive in a fixed radial relationship to the hub of a spindle motor. The disc mounting system includes curved spring elements, having a substantially C-shaped cross section, which are curved on a radius greater than the radius of the central opening of the discs. One or more spring elements are utilized with each disc, and assembly tooling is used to bend the spring elements so that the discs, with the opening of the C-shaped springs engaging the inner diameter of the discs, can fit over the hub of the spindle motor. The assembly tooling is then removed to allow the spring elements to partially straighten, firmly engaging the discs relative to the spindle motor hub in the radial direction. In a first embodiment of the invention, alternative mechanisms are disclosed for establishing the axial positions of the discs. In a second embodiment, a plurality of annular grooves are provided in the spindle motor hub and the spring elements engage both the discs and annular grooves in the spindle motor hub to fixedly locate the discs relative to the spindle motor hub in both the radial and axial directions. Fabrication of the spring elements from a shape-memory alloy is also disclosed.

Radially loaded disc mounting system for a disc drive

The present invention provides a compressive spring sleeve to reduce disc slippage in a disc drive resulting from non-operational mechanical shock, the disc drive having data storage discs in the form of a disc stack supported on the cylindrical hub of a spindle motor which spins the disc stack at a very high rotational speed. An annular space is provided between the inner diameters of the bores of the discs and the spacers and the outer diameter of the spindle motor hub, and the compressive spring sleeve is disposed in the annular space. The compressive spring sleeve has a spring body portion having radially extending and spaced apart peaks disposed about the circumference of the spring body portion to press against the discs at their inner diameters and thereby exert a restraining radial force against the discs so that the discs are maintained in a fixed concentric relationship relative to the spindle motor hub when a non-operational shock is exerted on the disc drive.

Compressive spring sleeve for reducing disc slippage

Method for the removable sealing of a component housing, and apparatus to practice the method using an elastic or conformable sealing band. The present invention teaches a sealing band, preferably elastic, to apply a horizontal seal to the horizontal seam defined by vertically assembled component case elements. The seal is maintained in position over the seam by an alignment element disposed on at least one of the seal and the case. The sealing band is rendered electrically conductive by admixing therewith a conductive material, or by plating thereon a conductive coating. A retaining element may be further added to at least one of the sealing band and the case to minimize tampering with the sealing band once installed.

Component sealing system

Differing gram loads and actuator arm resonances are compensated for through the method and apparatus of positioning z-height of outer actuator arm at an optimal height. Specifically, an actuator arm driven by a closed loop servo motor system for a disc drive system is configured so that the outer upper and lower actuator arms are positioned at an optimum distance, called optimum z-height, from the disc surface. At the optimum z-height position, the gram load of the outer actuator arms are shifted as near as possible to the gram load of the inner actuator arms. At the optimum z-height, the resonances on the head gimbal assemblies of the inner and outer actuator arms are closest.

Disc drive actuator arm assembly with outer arm z-height less than inner arm z-height

A disc mounting system for mounting the discs of a disc drive in a fixed radial relationship to the hub of a spindle motor. The disc mounting system includes curved spring elements, having a substantially C-shaped axial cross section, which are curved on a radius greater than the radius of the central opening of the discs. One or more spring elements are utilized with each disc, and assembly tooling is used to bend the spring elements so that the discs, with the opening of the C-shaped springs engaging the inner diameter of the discs, can fit over the hub of the spindle motor. The assembly tooling is then removed to allow the spring elements to partially straighten, firmly engaging the discs relative to the spindle motor hub in the radial direction. In a first embodiment of the invention, alternative mechanisms are disclosed for establishing the axial positions of the discs. In a second embodiment, a plurality of annular grooves are provided in the spindle motor hub and the spring elements engage both the discs and annular grooves in the spindle motor hub to fixedly locate the discs relative to the spindle motor hub in both the radial and axial directions. Fabrication of the spring elements from a shape-memory alloy is also disclosed.

The present invention includes a data disc support assembly for supporting a data disc relative to a head so data on a surface of the disc is accessible by the head. The support assembly includes a hub which has first and second axial ends and a flange extending from the second axial end. The flange supports the data disc. A clamp is connected to the hub to rigidly connect the data disc to the hub. The clamp has a first generally annular portion contacting the data disc and a second generally annular portion extending axially away from the hub beyond the first annular portion. The second annular portion is spaced from the data disc by a distance greater than the height of the head.

Disc clamp with head clearance

A disc mounting system for mounting the discs of a disc drive in a fixed radial relationship to the hub of a spindle motor. The disc mounting system includes one or more axially-extending tubular members inserted radially between the outer diameter of the spindle motor hub and the inner diameter of the discs. Various mechanisms for ensuring a tight radial connection between the spindle motor hub and the discs are disclosed.

A disc mounting system for mounting the discs of a disc drive in a fixed radial relationship to the hub of a spindle motor. The disc mounting system includes a disc mounting ring associated with each disc in the disc stack. The disc mounting ring includes at least one axially extending finger against which a portion of the inner diameter of the disc is brought to bear in an interference fit. In a first embodiment of the invention, the disc mounting ring includes a single finger and that portion of the inner diameter of the disc radially opposite the finger directly contacts the spindle motor hub. In other embodiments of the invention, the disc mounting ring includes a plurality of fingers spaced circumferentially about the ring and the inner diameter of the disc bears on all fingers and has no direct contact with the spindle motor hub. In all embodiments, it is envisioned that sufficient axial force will be applied to the discs at the time of manufacture to produce some cold-flowing of the disc mounting ring material of the fingers. Mechanisms for controlling the axial location of the discs relative to the spindle motor hub are also disclosed.

A disc drive for storing and retrieving data from at least one memory storage disc includes a drive base and a spindle motor. The spindle motor includes a rotor hub, a shaft, a bearing unit. The bearing unit rotatably supports the rotor hub about an axis. A controlled resistance electrical pathway is established from the rotor hub to ground to control disc potential and to prevent excess static charge buildup. In one embodiment, the spindle motor includes structural elements made of a conducting plastic having a controlled resistance to establish a controlled resistance electrical pathway from the rotor hub to ground. In a second embodiment, the shaft of the spindle motor includes a conductive contact button electrically connected to the shaft and operatively coupled with a contact shield electrically grounded by an electrical conductor having a controlled resistance. In another embodiment, the spindle motor includes a rod made of conductive material extending from an electrically grounded contact shield and received within the shaft. An electrical pathway between the shaft and the rod is established by a conducting fluid between the rod and the shaft. Alternatively, the electrical pathway from the shaft to the rod is established by a conducting unit. The conducting unit includes a seal, a magnetic conductive material, and a ferro-fluid. The seal is positioned within the shaft. The magnetic conductive material is coupled to the rod. The ferro-fluid is supported between the seal and the magnetic conductive material.

Disc drive spindle motor with controlled resistance pathway from disc to

Disc drive spindle motor with rotor isolation and controlled resistance

A reduced-height structure for a voice coil motor which forms a portion of the actuator in a disc drive data storage device includes a through opening in the base member of the disc drive housing within which the lower pole piece of the voice coil motor is mounted. A top pole piece of the Voice coil motor is mounted directly to the top cover of the disc drive housing and proper spacing between the top pole piece and the voice coil motor components mounted to the base a member is determined and maintained by a precisely machined surface in the base member. The lower pole piece is preferably mounted to the base member with cold-flowed brass rivets.

Voice coil motor for a disc drive

A disc drive for storing and retrieving data from at least one memory storage disc includes a drive base and a spindle motor. The spindle motor includes a rotor hub, a shaft, a bearing sleeve, and a bearing unit. The bearing unit is operably coupled to the rotor hub and includes an inner race secured to the shaft, an outer race secured to the bearing sleeve, and bearing balls fitted between the inner race and the outer race. The bearing balls rotatably support the rotor hub about an axis. At least one structural element of the spindle motor has a high resistivity so as to electrically isolate the hub from the base. In another embodiment, the drive base has an interface surface for coupling with the spindle motor. The interface surface includes a layer of high resistivity material. In another embodiment, the bearing ball is made of ceramic or ruby material to improve performance characteristics. In yet another embodiment, an insert is inserted between the bearing sleeve and the shaft to improve performance characteristics.

High resistivity bearing balls for spindle motor isolation

Method and apparatus for compensating for different gram loads and actuator arm resonances by positioning z-height of outer actuator arm at an optimum height. Specifically, an actuator arm driven by a closed loop servo motor system for a disc drive system is configured so that the outer upper and lower actuator arms are positioned at an optimum distance, called optimum z-height, from the disc surface. At the optimum z-height position, the resonances of the outer actuator arms are shifted as near as possible to the resonances of the inner actuator arms. At the optimum z-height, the gram loads on the head gimbal assemblies of the inner and outer actuator arms are closest for all z-heights measured. Accordingly, degradation of the performance of the servo motor system will be reduced.

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Scotts Valley, CA, United States of America

Michael John Raffetto