Patent Application
20090279211
(1) Technical Field
The present invention relates generally to hard disk drives (HDD), and more particularly to an improved device for mounting a pivot bearing to an actuator arm of a HDD.
(2) Description of the Prior Art
For the past several years, data storage methods have followed a tendency of escalating storage capacity while also shrinking the physical size occupied by its storage capacities. Introduction of ever more powerful computer hardware and software has contributed to increasing market pressures for less expensive, larger capacity and smaller packaging in disk drives. Storage device manufacturers make every effort to achieve any possible incremental cost savings that can be reasonably achieved without loss of technical performance and reliability.
A head disk assembly for a hard disk drive employs a rotary actuator apparatus including a pivot shaft that defines an actuator axis of rotation. The HDD is a device manufactured with a high degree of precision. Several fastening methods for holding the parts together are used. Generally, fasteners such as screws were used to enable the completed product to be serviced when defective. As anticipated, however, the inclination within the industry was to merely reject defective assemblies rather than rework them that led to a different fastening method using adhesives. This led to a new set of processing problems involving adhesives that are still being evaluated. Outgassing and long term effects on materials within the hard disk drive, connective strength of the adhesive, curing time and adhesive fatigue are a few of such concerns.
Briefly, single head designs for hard disk drives are typically “de-populated multi-head designs.
A single head de-populated design is illustrated in
The present invention allows an actuator to be made with fewer parts while reducing the total manufacturing cost by simplifying the assembly operation. Moreover, the present invention reduces tolerances in the actuator assembly while improving drive reliability and robustness. The parts and assembly costs for a magnetic disk drive represents a significant portion of the total cost of the drive apparatus.
It is an object of the invention to provide an improved method for the manufacture of a hard disk drive.
It is another object of the invention is to provide a hard disk drive with fewer and less expensive parts while reducing overall manufacturing cost and increasing performance.
It is still another object of the invention to simplify the overall assembly operation of the hard disk drive.
It is still another object of the invention to reduce manufacturing tolerances yet improving drive reliability and robustness.
It is yet another object of the invention is to provide a hard disk drive that does not add mass to the drive system thereby achieving reduction in the access time of the magnetic head to selected data tracks of the rotating disk.
It is still another object of the invention not to introduce foreign material into the disk drive. It will not outgas, corrode, wear, or fall off the suspension.
A novel application of geometries and kinematics design principles are at the center of the present invention. Applying these principles while integrating parts serve the assembly and improves reliability of the pivoting actuator. The design principles provide the full natural tolerance and constraint for the assembly of parts. Parts produced are easier to make, also, function much better as an assembly with zero-stress location.
The foregoing, together with other objects features and advantages of this invention, can be better appreciated with reference to the following specification, claims, and the accompanying drawings.
a, 2b, 2c and 2d illustrate various prior art methods for attaching a bearing to the actuator arm.
a is a cut-away top perspective view of an outer bearing sleeve of the invention.
b is a cut-away top perspective view of an outer bearing sleeve assembly of the invention.
a is an exploded top view of an outer bearing sleeve, of the invention, as applied to a conventional assembly utilizing a nut fastener.
b is an assembled bottom view of the outer bearing sleeve shown in
A head disk assembly for a hard disk drive employs a rotary actuator apparatus including a pivot shaft that defines an actuator axis of rotation. In the hard disk drive, a head suspension assembly positions a head slider over a magnetic disk to facilitate reading and writing of information to the disk. Across the spectrum from network servers to personal computers and desktop workstations to notebook systems, the capacity demands placed on hard disk drives are increasing faster than ever before. Because lower costs per megabyte are also desired, the conventional method of adding disks and heads is less and less appropriate. Instead, the primary engineering challenge is to continue to improve drive reliability, cost and useful life.
An improved pivot bearing assembly 20 is described. With reference to
Referring now to
In
Referring now to
In summary, a bearing assembly that is joined to an actuator suspension arm of a hard disk drive includes an actuator suspension arm that is stamped from a metal having a top and bottom surface and a threaded bore means defining an actuator axis of rotation. A bearing cartridge includes a reduced mass outer sleeve, the outer sleeve having an upper cylindrical member with a flanged lower member, the upper cylindrical member is threaded to engage with the threaded bore means of the suspension arm. The reduced mass outer sleeve has an internal spacer member to separate the outer races of conventional duplex bearings.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.
