A disk drive assembly having a disk hub having a cylindrical portion; and a disk clamp retaining portion formed on a vertical portion of the cylindrical portion of the disk hub; a disk clamp having: a body portion; and a retained portion which engages the disk clamp retaining portion of the disk hub to secure the disk clamp to the disk hub; and a disk media disposed between the disk clamp and the disk hub, the disk media being secured in place by the disk clamp.

FIELD

The present disclosure relates generally to information storage devices, and in particular to a disk drive having a disk clamp having a non-circular opening and a hub having a non-circular protrusion that is inserted into the non-circular opening.

BACKGROUND

Disk drives typically include a disk clamp that provides a disk clamping force for holding one or more disks to a hub. Thus, disk clamping is becoming more and more important not only for regular hard disk drive (HDD) performance but also under extreme conditions such as operational shock and non-operational shock. A reliable clamping force may maintain the integration of the whole disk pack, preventing the disk from separating or sliding under shock event. A reliable clamping force also helps limit the disk deflection, avoiding the disk contact with other components including arms, cover, base and suspensions under low G shock.

With increasingly thinner HDD design, disk clamping design may become challenging due to limitations of smaller form factors.

Further, in some designs scraping or scratching can occur between the disk clamp, disk hub, and disk media during assembly and such scraping or scratching can cause particles of material to be generated that can interfere with the operation of the HDD.

There is therefore a need for an improved disk clamp design and assembly process.

DETAILED DESCRIPTION

Referring toFIG. 1, a disk drive100is illustrated, according to one embodiment. The disk drive100comprises a hub102, a disk104physically contacting and supported by at least one mounting surface (not labeled inFIG. 1, shown inFIG. 4below) of the hub102, and a head106operable to write to and read from the disk104. In one embodiment, the hub102comprises a substantially cylindrical portion108which define a longitudinal axis L and a mounting surface (not labeled inFIG. 1, shown inFIG. 4below) substantially normal to the longitudinal axis L, the mounting surface (not labeled inFIG. 1, shown inFIG. 4below) extending radially outward.

As illustrated herein, the disk drive100comprises a magnetic disk drive, and the structures and methods described herein will be described in terms of such a disk drive. However, these structures and methods may also be applied to and/or implemented in other disk drives, including, e.g., optical and magneto-optical disk drives.

The disks104may comprise any of a variety of magnetic or optical disk media having a substantially concentric opening114defined there through. Of course, in other embodiments, the disk drive100may include more or fewer disks. For example, the disk drive100may include one disk or it may include two or more disks. The disks104each include a disk surface116, as well as an opposing disk surface not visible inFIG. 1. In one embodiment, the disk surfaces116comprise a plurality of generally concentric tracks for storing data.

As illustrated, the hub102may be coupled to and support the disks104. The hub102may also be rotatably attached to a motor base118of the disk drive100, and may form one component of a motor120(e.g., a spindle motor). The motor120and the hub102may be configured to rotate the disks104about the longitudinal axis L.

Further, a disk clamp140may be coupled to the hub102to provide a downward clamping force to the disks104. Specifically, the disk clamp140may be positioned above the disks104and attached to an upper surface of the hub102. The interaction of the disk clamp140and the hub102to provide the downward clamping force is discussed in more detail below.

The disk drive100may further include a cover122, which, together with the motor base118, may house the disks104and the motor120. The disk drive100may also include a head stack assembly (“HSA”)124rotatably attached to the motor base118. The HSA124may include an actuator126comprising an actuator body128and one or more actuator arms130extending from the actuator body128. The actuator body128may further be configured to rotate about an actuator pivot axis.

One or two head gimbal assemblies (“HGA”)132may be attached to a distal end of each actuator arm130. Each HGA132includes a head106operable to write to and read from a corresponding disk104. The HSA124may further include a coil134through which a changing electrical current is passed during operation. The coil134interacts with one or more magnets136that are attached to the motor base118to form a voice coil motor (“VCM”) for controllably rotating the HSA124.

The head106may comprise any of a variety of heads for writing to and reading from a disk104. In magnetic recording applications, the head106may include an air bearing slider and a magnetic transducer that includes a writer and a read element. The magnetic transducer's writer may be of a longitudinal or perpendicular design, and the read element of the magnetic transducer may be inductive or magneto resistive. In optical and magneto-optical recording applications, the head may include a mirror and an objective lens for focusing laser light on to an adjacent disk surface.

The disk drive100may further include a printed circuit board (“PCB”) (not shown). The PCB may include, inter alia, a disk drive controller for controlling read and write operations and a servo control system for generating servo control signals to position the actuator arms130relative to the disks104.

FIG. 2is a perspective view illustrating a first example embodiment of the disk hub102ofFIG. 1. As illustrated, the hub102comprises a cylindrical portion108and a mounting surface (not labeled inFIG. 2, shown inFIG. 4below) on which a disk104has been mounted inFIG. 2. The cylindrical portion108has a sidewall that forms a vertical surface202.

A notch204is formed in the vertical surface202of the sidewall of the cylindrical portion108. In some embodiments, the notch204may be formed with a semi-circumferential shape formed in the vertical surface202of the sidewall. This notch204engages a retained feature304of a disk clamp140(shown inFIG. 3below). The notch204may include an entry portion206and a retaining portion208. The entry portion206of the notch204forms a region of the cylindrical portion108which has a reduced radius210at the upper most portion of the vertical surface202. Further, the retaining portion208of the notch204forms (1) a region of the cylindrical portion108which has a radius212substantially equal to the average radius of the cylindrical portion108at the uppermost portion of the vertical surface202, and (2) a region having a reduced radius at a portion of the vertical surface202below the uppermost portion. Thus, a retaining lip214is formed above the retaining portion208.

In some embodiments, more than one notch204may be formed in vertical portion202of the cylindrical portion108of the hub102. The number of notches is not particularly limited, to any number. Additionally, two or more notches may be connected by a groove (not shown) provided, such that the two or more notches communicate there between.

FIG. 3is a perspective view illustrating a first example embodiment of the disk clamp140ofFIG. 1. As illustrated, the clamp140includes a body302from which one or more retaining tabs304extend. Additionally, the clamp140includes one or more disk pressure applying portions306, which extend from the body302, and which contacts the disk104to apply a clamping force.

In some embodiments, the body302may have an annular shape, which is inclined in a radial direction. Additionally, on some embodiments, the one or more retaining tabs304extend radially inward from the body portion302. Further, in some embodiments the one or more disk pressure applying portions extend radially outward from the body portion302.

Further, the body302is formed so as to be deformable such that disk pressure applying portion306may be deflected upward (with respect to the retaining tabs304) prior to installation of the disk clamp140on the disk hub102. More specifically, the disk pressure applying portion306may be deflected, and while being maintained in a deflected state, the retaining tabs304of the disk clamp140are aligned with the entry portions206of the notches204of the disk hub102. Once the retaining tabs304of the disk clamp140are aligned with the entry portions206of the notches204of the disk hub102, the disk clamp140and disk hub102are moved toward each other. Then, the disk clamp140and the disk hub102are rotated with respect to each other until at least one of the disk retaining tabs304of the disk clamp140engages a retaining portion208of a notch204of the disk hub102. The deflection and installation are discussed in more detail below.

Further, in some embodiments, one or more notches308may be provided in the one or more disk pressure applying portions306to provide a gripping location for deflection of the disk pressure applying portions306.

FIG. 4is a perspective view illustrating a second example embodiment of a disk hub402similar to the disk hub102ofFIGS. 1 and 2. This second example embodiment of the disk hub402has some features similar to the first example embodiment such that redundant description is omitted.

As illustrated, the hub402comprises a cylindrical portion408(similar to the cylindrical portion108shown inFIGS. 1 and 2) and a mounting surface142on which a disk104has been mounted inFIG. 2. The cylindrical portion408has a sidewall that forms a vertical surface410.

At least one retaining tab412is formed in the vertical surface202of the sidewall of the cylindrical portion408. This retaining tab412engages a retained feature504of a disk clamp540(shown inFIG. 5below).

In some embodiments, more than one retaining tab412extends from the vertical surface410of the disk hub402. The number of retaining tabs412is not particularly limited to any number.

Further, in some embodiments, the tabs412may be regularly spaced around the circumference of the cylindrical portion408of the disk hub402. Further, one or more entry notches414may be formed between adjacent retaining tabs412. The entry notches414form regions of the cylindrical portion408that have a radius418substantially equal to the average radius of the cylindrical portion408at the uppermost portion of the vertical surface410. Further, the retaining tabs412form regions of the cylindrical portion408which have a radius416greater than the radius418of the regions of the cylindrical portion formed by the entry notches414. Thus, a retaining lip420is formed below the retaining tab412.

FIG. 5is a perspective view illustrating a second example embodiment of a disk clamp540similar to the disk clamp140ofFIGS. 1 and 3. This second example embodiment of the disk hub402has some features similar to the first example embodiment such that redundant description may be omitted.

As illustrated, the clamp540includes a body502from which one or more retaining tabs504extend. Additionally, the clamp540includes a disk pressure applying portion506, which extends from the body502, and which contacts the disk104to apply a clamping force.

In some embodiments, the body502may have a flat disk shape, which extends in a radial direction. Additionally, on some embodiments, the one or more retaining tabs504extend radially inward from the body portion502. Further, in some embodiments the disk pressure applying portion extends radially outward from the body portion502. Further, in some embodiments the body502may have an inclined region510disposed radially inward of the disk pressure applying portion506.

Further, the body502is formed so as to be deformable such that disk pressure applying portion506may be deflected upward (with respect to the retaining tabs504) prior to installation of the disk clamp140on the disk hub102. Specifically, the inclined region510may be deformable. More specifically, the disk pressure applying portion506may be deflected, and while being maintained in a deflected state, the retaining tabs504of the disk clamp540are aligned with the entry notches414of the disk hub402. Once the retaining tabs504of the disk clamp540are aligned with the entry notches414of the disk hub402, the disk clamp540and disk hub402are moved toward each other. Then, the disk clamp540and the disk hub402are rotated with respect to each other until at least one of the disk retaining tabs504of the disk clamp540engages a retaining tab412of the disk hub402. After, at least one of the retaining tabs504of the disk clamp504engages a retaining tab412of the disk hub402, the deflection of the disk pressure applying portion506is released, and engages the disk104. The deflection and installation are discussed in more detail below.

Further, in some embodiments, one or more notches512may be provided in the pressure applying portion506to provide a gripping location for deflection of the disk pressure applying portion506.

FIG. 6is a partial section view of the second example embodiment of the disk hub and second example embodiment of the disk clamp in a deflected state. Further,FIG. 7is a partial section view of the second example embodiment of the disk hub and second example embodiment of the disk clamp in a non-deflected state.

As illustrated, inFIGS. 6 and 7, the disk clamp540has been mounted to the disk hub402with the disk104disposed there between. Specifically, as discussed above, to reach the configuration as shown inFIG. 7, the disk pressure applying portion506is deflected as shown inFIG. 6, the retaining tabs504of the disk clamp540are aligned with the entry notches414of the disk hub402, and the disk clamp540and disk hub402are moved toward each other. As shown inFIG. 6, the deflection of the disk pressure applying portion506creates an air gap602between the disk104and the disk pressure applying portion506.

After the disk clamp540and the disk hub402are moved toward each other, the disk clamp540and the disk hub402are rotated with respect to each other until at least one of the disk retaining tabs504of the disk clamp540engages a retaining tab412of the disk hub402as shown inFIGS. 6 and 7. The portion of the disk retaining tab504of the disk clamp540that engages the retaining tab412of the disk hub402is an engaging feature604. In this example embodiment, the engaging feature604extends radially inward in a substantially horizontal direction. However, the engaging feature604is not limited to this configuration as shown below.

As shown inFIG. 6, after the retaining tab504of the disk clamp540engages the retaining tab412of the disk hub402, the deflection of the disk pressure applying portion506is released, and the disk pressure applying portion506engages the disk104. By pre-deflecting the disk pressure applying portion506of the disk clamp540and then rotating the disk clamp540and the disk hub402with respect to each other, friction across the disk104may be reduced, which can reduce the amount of scrub or particles generated during assembly. However, an embodiment need not have a reduction in the amount of scrub or particles generated.

FIG. 8is a partial section view of a third example embodiment of the disk hub and a third example embodiment of the disk clamp in a deflected state. Further,FIG. 9is a partial section view of the third example embodiment of the disk hub and the third example embodiment of the disk clamp in a non-deflected state. The third example embodiment of the disk hub and the third example embodiment of the disk clamp are similar to the second example embodiments of the disk hub and disk clamp discussed above with respect toFIGS. 4-7. Thus, similar reference numerals are used for similar features.

As illustrated, inFIGS. 8 and 9, the disk clamp540has been mounted to the disk hub402with the disk104disposed there between. Specifically, as discussed above, to reach the configuration inFIG. 9, the disk pressure applying portion506is deflected as shown asFIG. 8, the retaining tabs504of the disk clamp540are aligned with the entry notches414of the disk hub402and the entry notches414of the disk hub402, and the disk clamp540and disk hub402are moved toward each other. As shown inFIG. 8, the deflection of the disk pressure applying portion506creates an air gap602between the disk104and the disk pressure applying portion506.

After the disk clamp540and the disk hub402are moved toward each other, the disk clamp540and the disk hub402are rotated with respect to each other until at least one of the disk retaining tabs504of the disk clamp540engages a retaining tab412of the disk hub402as shown inFIGS. 8 and 9. The portion of the disk retaining tab504of the disk clamp540that engages the retaining tab412of the disk hub402is an engaging feature804. In this example embodiment, the engaging feature804extends radially inward at an angle between a substantially horizontal direction and a substantially vertical direction. However, the engaging feature804is not limited to this configuration and may extend in a substantially horizontal direction as discussed above, or may extend in a substantially vertical direction to engage the disk hub402.

As shown inFIG. 9, after the retaining tab504of the disk clamp540engages the retaining tab412of the disk hub402, the deflection of the disk pressure applying portion506is released, and the disk pressure applying portion506engages the disk104. By pre-deflecting the disk pressure applying portion506of the disk clamp540and then rotating the disk clamp540and the disk hub402with respect to each other, friction across the disk104may be reduced, which can reduce the amount of scrub or particles generated during assembly. However, an embodiment need not have a reduction in the amount of scrub or particles generated.

FIG. 10illustrates a flow chart for a method1000of manufacturing a disk drive, according to one illustrated embodiment. This method1000will be discussed in the context of the hub102and the disk clamp140ofFIGS. 1-3. However, the acts disclosed herein may be executed using a variety of different disk hubs and disk clamps, in accordance with the described method. For example, the acts disclosed herein may alternatively be executed using the hub402and the disk clamp540ofFIGS. 4-9.

As described herein, at least some of the acts comprising the method1000may be orchestrated by a processor according to an automatic disk drive manufacturing algorithm, based at least in part on computer-readable instructions stored in computer-readable memory and executable by the processor. A manual implementation of one or more acts of the method1000may also be employed, in other embodiments.

At act1010, a disk hub102, a disk104and a disk clamp140are provided. The hub102may define a mounting surface142and a cylindrical portion108having a vertical surface202. In some embodiments, a notch204may be formed in the vertical surface202of the hub102.

The disk clamp140may define a body302from which one or more retaining tabs304extend radially inward. Further, the disk clamp140may also define one or more disk pressure applying portions306extending radially outward to form a circumferential region of the disk clamp140.

The disk104may define an opening there through having an inner diameter. The disk104may be formed in a variety of ways. In one embodiment, the media of the disk104may be formed, and then the first disk104may be stamped, cast, machined or otherwise formed to define the first opening.

The hub102may also be formed in a variety of ways. In one embodiment, the hub102may be machined to form the mounting surface142, the cylindrical portion108and the vertical surface202. In other embodiments, the hub102may be cast, molded or machined to form the mounting surface142and the vertical surface202. In still other embodiments, other manufacturing techniques may be employed.

Similarly, the manufacturing method of the disk clamp140is not particularly limited and may include machining, casting, molding, or any other methods as would be apparent to a person of ordinary skill in the art.

At act1015, the disk104is positioned against the mounting surface142of the hub102. The cylindrical portion108of the hub102may be inserted through the opening formed in the disk104and the disk104may be positioned in physical contact with the mounting surface142. In some embodiments, a machine vision system may help align the disk104and the mounting surface142of the hub102.

At act1020, the one or more disk pressure applying portions forming a circumferential region of the disk clamp140are deflected above body portion302disposed radially inward of the circumferential region of the disk clamp140. The deflection can be performed by a user manually grasping the disk pressure applying portions306. Alternatively, a machine may grasp the disk pressure applying portions306using one or more notches308formed in the circumferential region of the disk clamp140.

At act1025, while the disk pressure applying portions306are held in a deflected state, the retaining tabs304of the disk clamp140are positioned to engage the notches204formed in the vertical surface of the hub102. Specifically, the retaining tabs304of the disk clamp140are aligned with the entry portions206of the notches204of the disk hub102. Once the retaining tabs304of the disk clamp140are aligned with the entry portions206of the notches204of the disk hub102, the disk clamp140and disk hub102are moved toward each other. Then, the disk clamp140and the disk hub102are rotated with respect to each other until at least one of the disk retaining tabs304of the disk clamp140engages a retaining portion208of a notch204of the disk hub102. In some embodiments, a machine vision system may help align the disk clamp140and the disk hub102. Further, the rotation of the disk clamp140and the disk hub102with respect to each other may be performed manually by a user or may be performed automatically by a machine. The machine is not particularly limited.

At act1030, the deflection of the disk pressure applying portion306is released, and disk pressure applying portion306returns to an un-deformed state so as to engage the disk104.

The foregoing detailed description has set forth various embodiments of the devices and/or processes via the use of block diagrams, schematics, and examples. Insofar as such block diagrams, schematics, and examples contain one or more functions and/or operations, each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one embodiment, the present subject matter may be implemented via Application Specific Integrated Circuits (ASICs). However, the embodiments disclosed herein, in whole or in part, can be equivalently implemented in standard integrated circuits, as one or more programs executed by one or more processors, as one or more programs executed by one or more controllers (e.g., microcontrollers), as firmware, or as virtually any combination thereof.