Abstract:
Various apparatus and methods are provided for positioning and handling hard memory disks. A disk carrier is provided with adjustably positionable side wall inserts. The inserts or panels may be moved between a plurality of positions to accommodate disks of different diameters. The inserts may also be substituted to accommodate disks of different thickness or different orientations, such as pairs of disks in gap merge orientation or contact merge orientation.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]    Priority is claimed from U.S. Provisional Patent Application Serial No. 60/417,630 filed Oct. 10, 2002, which is incorporated by reference herein in its entirety.  
         [0002]    The subject matter of the present application is related to the following applications, each of which has a filing date of May 9, 2003: Attorney Docket No. 3123-479 entitled Single-Sided Sputtered Magnetic Recording Disks to Clasara et al.; Attorney Docket No. 3123-480 entitled Dual Disk Transport Mechanism Processing Two Disks Tilted Toward Each Other to Grow et al.; Attorney Docket No. 3123-481 entitled Information-Storage Media With Dissimilar Outer Diameter and/or Inner Diameter Chamfer Designs On Two Sides to Clasara et al.; Attorney Docket No. 3123-483 entitled Method of Merging Two Disks Concentrically Without Gap Between Disks to Buitron; Attorney Docket No. 3123-484 entitled Apparatus for Combining or Separating Disk Pairs Simultaneously to Buitron et al.; Attorney Docket No. 3123-485 entitled Method of Simultaneous Two-Disk Processing of Single-Sided Magnetic Recording Disks to Buitron et al.; Attorney Docket No. 3123-487 entitled W-Patterned Tools for Transporting/Handling Pairs of Disks to Buitron et al.; Attorney Docket No. 3123-491 entitled Method for Servo Pattern Application on Single-Side Processed Disks in a Merged State to Valeri; Attorney Docket No.3123-518 entitled Method for Simultaneous Two-Disk Texturing to Buitron et al.; Attorney Docket No. 3123-521 entitled Automated Merge Nest for Pairs of Magnetic Storage Disks to Crofton et al.; Attorney Docket No. 3123-522 entitled Apparatus for Simultaneous Two-Disk Scrubbing and Washing to Crofton et al.; Attorney Docket No. 3123-523 entitled Cassette Apparatus for Holding 25 Pairs of Disks for Manufacturing Process to Buitron et al.; and Attorney Docket No. 3123-524 entitled Method of Lubricating Multiple Magnetic Storage Disks in Close Proximity to Buitron et al. Each of these applications is incorporated by reference in its entirety as if stated herein. 
     
    
     
       FIELD OF THE INVENTION  
         [0003]    The present invention relates to a method and apparatus for handling disks. More specifically, the present invention relates to a modular cassette which is changeable to handle different disk form factors.  
         BACKGROUND OF THE INVENTION  
         [0004]    Hard disk drives are an efficient and cost effective solution for data storage. Depending upon the requirements of the particular application, a disk drive may include anywhere from one to eight hard disks and data may be stored on one or both surfaces of each disk. While hard disk drives are traditionally thought of as a component of a personal computer or as a network server, usage has expanded to include other storage applications such as set top boxes for recording and time shifting of television programs, personal digital assistants, cameras, music players and other consumer electronic devices, each having differing information storage capacity requirements.  
           [0005]    Typically, hard memory disks are produced with functional magnetic recording capabilities on both sides or surfaces of the disk. In conventional practice, these hard disks are produced by subjecting both sides of a raw material substrate disk, such as glass, aluminum or some other suitable material, to numerous manufacturing processes. Active materials are deposited on both sides of the substrate disk and both sides of the disk are subject to full processing such that both sides of the disk may be referred to as active or functional from a memory storage stand point. The end result is that both sides of the finished disk have the necessary materials and characteristics required to effect magnetic recording and provide data storage. These are generally referred to as double-sided process disks. Assuming both surfaces pass certification testing and have no defects, both sides of the disk may be referred to as active or functional for memory storage purposes. These disks are referred as double-sided test pass disks. Double-sided test pass disks may be used in a disk drive for double-sided recording.  
           [0006]    Conventional double-sided processing of hard memory disks involves a number of discrete steps. Typically, twenty-five substrate disks are placed in a plastic cassette, axially aligned in a single row. Because the disk manufacturing processes are conducted at different locations using different equipment, the cassettes are moved from work station to work station. For most processes, the substrate disks are individually removed from the cassette by automated equipment, both sides or surfaces of each disk are subjected to the particular process, and the processed disk is returned to the cassette. Once each disk has been fully processed and returned to the cassette, the cassette is transferred to the next work station for further processing of the disks.  
           [0007]    More particularly, in a conventional double-sided disk manufacturing process, the substrate disks are initially subjected to data zone texturing. Texturing prepares the surfaces of the substrate disks to receive layers of materials which will provide the active or memory storage capabilities on each disk surface. Texturing may typically be accomplished in two ways: fixed abrasive texturing or free abrasive texturing. Fixed abrasive texturing is analogous to sanding, in which a fine grade sand paper or fabric is pressed against both sides of a spinning substrate disk to roughen or texturize both surfaces. Free abrasive texturing involves applying a rough woven fabric against the disk surfaces in the presence of a slurry. The slurry typically contains diamond particles, which perform the texturing, a coolant to reduce heat generated in the texturing process and deionized water as the base solution. Texturing is typically followed by washing to remove particulate generated during texturing. Washing is a multi-stage process and usually includes scrubbing of the disk surfaces. The textured substrate disks are then subjected to a drying process. Drying is performed on an entire cassette of disk drives at a time. Following drying, the textured substrate disks are subjected to laser zone texturing. Laser zone texturing does not involve physically contacting and applying pressure against the substrate disk surfaces like data zone texturing. Rather, a laser beam is focused on and interacts with discrete portions of the disk surface, primarily to create an array of bumps for the head and slider assembly to land on and take off from. Laser zone texturing is performed one disk at a time. The disks are then washed again. Following a drying step, the disks are individually subjected to a process which adds layers of material to both surfaces for purposes of creating data storage capabilities. This can be accomplished by sputtering, deposition or by other techniques known to persons of skill in the art. Following the addition of layers of material to each surface, a lubricant layer typically is applied. The lubrication process can be accomplished by subjecting an entire cassette of disks to a liquid lubricant; it does not need to be done one disk at a time. Following lubrication, the disks are individually subjected to surface burnishing to remove asperities, enhance bonding of the lubricant to the disk surface and otherwise provide a generally uniform finish to the disk surface. Following burnishing, the disks are subjected to various types of testing. Examples of testing include glide testing to find and remove disks with asperities that could affect flying at the head/slider assembly and certification testing which is writing to and reading from the disk surfaces. Certification testing is also used to locate and remove disks with defects that make the surface unuseable for data storage. The finished disks can then be subjected to a servo-writing process and placed in disk drives, or placed in disk drives then subjected to servo-writing. The data zone texturing, laser zone texturing, scrubbing, sputtering, burnishing and testing processes are done one disk at a time, with each surface of a single disk being processed simultaneously.  
           [0008]    Although the active materials and manufacturing processes, by their nature, are difficult and expensive to employ, over the years, the technology used to manufacture hard memory disks has rapidly progressed. As a result, the density of information that can be stored on a disk surface is remarkable. Indeed, double-sided test pass disks used in personal computers have much greater storage capacity than most consumers require during the useful life of the computer. Consumers thus are forced to pay substantial amounts for excess storage capacity and the components to access the excess storage capacity. This has caused some disk drive manufacturers, in some current applications, to manufacture and sell disk drives which utilize only one side of a double-sided test pass disk for storage purposes or which use the good side of a double-sided process disk where one surface passed certification testing and the second surface failed. In either case, the second surface, despite being fully processed, is unused. However, the disk drive manufacturer reduces its cost by eliminating the mechanical and electrical components needed to access the unused disk surface. These disk drives are referred to as single-side drives and are typically used in low-end or economy disk drives to appeal to the low cost end of the marketplace. Although this approach may reduce some cost, it does not reduce the wasted cost of manufacturing the unused storage surface of each disk. Thus, substantial savings can be achieved by not only manufacturing disks with a single active or functional side, but doing so in a cost-effective manner.  
           [0009]    In contrast to a double-sided disk, a single-sided disk has only one functional memory surface with active recording materials. It is not a double-sided process disk where one side is not accessed or where one side has failed testing. Rather, manufacturing processes are applied in a controlled manner only to one side of the disk using unique single-sided processing techniques. In contrast to conventional double-sided disks, active recording materials are only applied to, and full processing is only conducted on, one side of the disk. Thus, substantial savings are achieved by eliminating processing the second side of each disk.  
           [0010]    Additionally, the present invention achieves advantages by utilizing conventional double-sided disk manufacturing equipment and processes, with limited modification. The present invention enables simultaneous processing of two substrate disks through the same equipment and processes used to manufacture double-sided disks. Simultaneously processing two substrate disks results in the production of two single-sided disks in the same time and using essentially the same equipment as currently is used in the production of one double-sided disk. However, each single-sided disk has only a single active or functional surface. For illustrative purposes FIG. 1 shows a side-by-side schematic representation of the processing of one double-sided disk D d , depicted on the left side of FIG. 1, versus the simultaneous processing of two single-sided disks D s , depicted on the right side of FIG. 1. In each case, the double-sided disk or the two single-sided disks are subjected to the same process steps  1  through N, but the single-sided disk processing produces two disks in the same time the double-sided disk processing produces one disk.  
           [0011]    A benefit provided by simultaneous single-sided processing of disks is a substantial cost savings achieved by eliminating the application of materials to and processing of one side of each disk. A further, and potentially significant cost savings can be achieved by utilizing existing double-sided disk processing equipment, with limited modification, to process pairs of single-sided disks. A still further benefit is a substantial increase in production (or reduction in processing time depending upon perspective). By utilizing existing double-sided disk processing equipment, approximately twice the productivity of a conventional double-sided production process is achieved (on the basis of numbers of disks produced) in the production of single-sided disks. Moreover, these increased productivity levels are achieved at approximately the same material cost, excepting the substrate disk, as producing half as many double-sided disks.  
           [0012]    The simultaneous processing is achieved by combining two substrate disks together into a substrate disk pair or disk pair. A disk pair is two substrate disks that are oriented in a back-to-back relationship with the back-to-back surfaces either in direct physical contact or closely adjacent with a slight separation. The separation can be achieved with or without an intervening spacer. The substrate disk pair progresses through each process step in much the same way as one double-sided disk, but with only the outwardly facing surface of each disk in the pair being subjected to the full process. Thus, the outwardly facing surface of each pair becomes the active or functional surface and the inwardly facing surface of each pair remain inactive or non-functional.  
           [0013]    For convenience and understanding, the following terms will have the definitions set forth:  
           [0014]    a) “R-side” and “L-side” refer to the active side and inactive side of a disk, respectively. R-side is the side that does or will have active recording materials and memory capability. The R-side may also be referred to as the active or functional side. The L-side is the side that has little or no active recording materials or memory capabilities; it is non-functional or inactive from a data storage stand point.  
           [0015]    b) “Merge” means to bring two disks closer together to form a pair of disks, a disk pair or a substrate pair.  
           [0016]    c) “Demerge,” conversely, means that a merged pair of disks is separated from each other.  
           [0017]    d) “Disk” means a finished memory disk and all predecessor configurations during the manufacturing process starting with a substrate disk and progressing to a finished memory disk, depending upon the context of the sentence in which it is used.  
           [0018]    e) “Disk pair” or “substrate pair” means two disks positioned in contact merge, gap merge or spacer merge orientation.  
           [0019]    f) “Double-sided disk” means a single disk which has been subjected to double-sided processing, whether or not both sides of the disk have passed testing or only one side has passed testing.  
           [0020]    g) “Gap merge” means a pair of disks that have been merged, but a space is maintained between the two merged disks. One or more spacers may or may not be used to maintain the gap or space. Gap merge includes both concentric and non-concentric merge. It should be understood that there is no precise dimension or limit to the space between the disks that causes them to be gap merged. Gap merge also includes the situation where the gap between the disks gradually decreases from one perimeter edge to the opposite perimeter edge of the disks when the two disks are angled toward each other. An example is when the bottom perimeter edges of the disks are spaced apart and the upper perimeter edges are in contact.  
           [0021]    h) “Single-sided disks” means a single disk which has been subjected to single-side processing, where only one surface of the disk is fully processed.  
           [0022]    i) “Spacer merge” means a spacer body is used to create spacing between two gap-merged disks.  
           [0023]    j) “Contact merge” means a merged pair of disks where the inside surface of each disk is in contact with the inside surface of the other disk. Contact merge includes concentric and non-concentric merge.  
           [0024]    k) “Concentric merge” means that two merged disks have the same axis and, assuming the two disks have the same outside diameter and inside diameter (as defined by the center aperture), their outer and inner perimeter edges are aligned.  
           [0025]    l) “Concentric contact merge” means a pair of disks that are oriented in both a contact merge and a concentric merge.  
           [0026]    m) “Non-concentric merge” or “off-centered merge” means the two merged disks are not concentric to each other or their perimeter edges are not aligned.  
           [0027]    n) “Non-concentric contact merge” means the two contact merged disks are not concentric to each other or their perimeter edges are not aligned.  
           [0028]    Referring to FIG. 2, a cross-section of a pair of gap-merged disks is shown. The R-side (active or functional side) is the outwardly facing surface R of each disk within the pair. The L-side (inactive or nonfunctional side) is the inwardly facing surface L of each disk within the pair. In comparison, a cross-section of a pair of concentric contact merged disks is shown in FIG. 3. The relative orientation of the R-side and L-side of each disk remains the same, however, the L-side of each disk of the pair are in contact and the outer and inner perimeter P of each disk is aligned with the outer and inner perimeter P of the other disk.  
           [0029]    A conventional double-sided disk is shown in FIG. 4. The left side surface is referred to as the “A” side and the right side surface is referred to as the “B” side. Both the A and B sides are subjected to processing, including the addition of active or magnetic materials. In contrast, with reference to FIGS. 2 and 3, the R-side of each disk in a pair of disks is oriented on the outside of the pair and is subjected to processing in the same fashion as the A and B sides of a double-sided disk. Conversely, the L-side of each disk in a pair of disks is oriented on the inside of the pair and is not subjected to full processing in the same fashion as the A and B sides of a double-sided disk.  
         SUMMARY OF THE INVENTION  
         [0030]    The present invention is a modular cassette with two primary parts. The first part is a main body and the second part is a pair of side wall inserts. The side wall inserts are those portions of the cassette which contact disks. The inserts may be positioned at different locations relative to the main body to accommodate a range of disk form factors. They are removable from the cassette and adjustable within the cassette. For manufacturability, the inserts are also preferably identical, such that an insert may simply be rotated 180 degrees and attach to the opposite side of the cassette. Preferably, this universal or modular cassette will be made from plastic. A combination of different plastics may be used for different purposes, such as different manufacturing processes in which the cassette is exposed to different environments. Stainless steel rods or other metal reinforcing members may be embedded within the inserts and other component pieces to provide rigidity to the structure to prevent bending, bowing and/or warping. Alternatively, the component pieces can be machined from metal parts. In one embodiment, the modular or universal cassette is configured to handle disk outside diameters ranging from 65 millimeters to 95 millimeters. Similarly, different inserts can be utilized for different disk orientations, such as equally spaced disks, gap merge disks or contact merge disks, simply by replacing or substituting differently configured inserts. Also, the inserts can be configured to hold different numbers of disks within the same cassette main body. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0031]    [0031]FIG. 1 is a schematic of a double-sided disk manufacturing process, showing process steps  1  through N on the left side of the illustration, and showing a single-sided disk manufacturing process of process steps  1  through N on the right side.  
         [0032]    [0032]FIG. 2 is a cross-section of a gap merge pair of disks.  
         [0033]    [0033]FIG. 3 is a cross-section of a concentric contact merge pair of disks.  
         [0034]    [0034]FIG. 4 is a cross-section of a double-sided process disk.  
         [0035]    [0035]FIG. 5 is a perspective view of one embodiment of the modular cassette of the present invention.  
         [0036]    [0036]FIG. 6 is a top plan view of the embodiment of FIG. 5.  
         [0037]    [0037]FIG. 7 is an exploded perspective view of the embodiment of FIG. 5.  
         [0038]    [0038]FIG. 8 is an exploded end view of the embodiment of FIG. 7.  
         [0039]    [0039]FIG. 9 is a side elevation view of the embodiment of FIG. 5.  
         [0040]    [0040]FIG. 10 is a schematic end view of the embodiment of FIG. 5 in a first configuration.  
         [0041]    [0041]FIG. 11 is a schematic end view of the embodiment of FIG. 5 in a second configuration.  
         [0042]    [0042]FIG. 12 is a schematic end view of the embodiment of FIG. 5 in a third configuration.  
         [0043]    [0043]FIG. 13 is an end view of a side wall insert.  
         [0044]    [0044]FIG. 14 is a partial top plan view of a side wall insert with ribs configured in a contact merge orientation.  
         [0045]    [0045]FIG. 15 is a partial top plan view of a side wall insert member with ribs configured in a gap merge orientation. 
     
    
       [0046]    It should be understood that the drawings are not necessarily to scale. In certain instances, details which are not necessary for an understanding of the invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0047]    Turning to FIG. 5, a first embodiment of the universal cassette or caddy  10  of the present invention is shown. The cassette comprises a main body  12  and a pair of removable or adjustable side wall inserts  14  and  16 . The cassette has an open top  18 , open bottom  20  and U-shaped openings  22  in the end walls  24 . The U-shaped opening allows access to the central aperture of the disks. The open top and open bottom also provide access to the disks. A disk D is shown seated in the cassette. The main body further includes two integral side walls  26 ,  28  which extend between end walls. A plurality of slots or holes  30  are formed in the integral side walls  26 ,  28  and in the inserts. The slots allow process fluids to be drained from the cassette and disks during processing. While the side walls  26 ,  28  are illustrated as integrally formed with the end walls  24 , they may be separate pieces secured between the end walls. Similarly, a pair of base members  30  extend between the two end walls along the bottom of the cassette. The base members also provide rigidity to the cassette and form a support structure upon which the cassette rests (FIG. 8). The base members maybe integrally formed with the end walls, or may be formed as separate pieces secured to the end walls through appropriate fasteners.  
         [0048]    The side wall inserts  14 ,  16  are generally shown in FIGS. 5, 7,  8  and  14 . In general terms, the inserts preferably comprise a vertical wall portion  34  and a second wall portion  36  forming an obtuse angle with the vertical wall portion and angled inwardly toward the open inside of the cassette. The inside surfaces of both the vertical and second wall portions  34 ,  36 , shown in FIGS.  5 - 7 , include a row of ribs  38 , which define a row of disk receiving grooves or channels  40 . The relative size and spacing of the ribs is determined based upon the form factor of the disk to be utilized. In addition, slots  30  are also formed between the ribs, along both the vertical wall portion  34  and second wall portion  36 , to allow process fluids to enter into and escape from the cassette.  
         [0049]    As best shown in FIGS. 5 and 7, horizontal support members  42 ,  44  extend along the length of each insert. The support members provide structural rigidity to the inserts  14 ,  16  to prevent bending, warpage or breakage. The support members may be hollow, may be solid, or may contain a strengthening rod made of metal or other suitable material for the environment. In addition, each end of the support members is provided with a securement area  46  which correspond to similar securement areas  48 ,  50  and  52  formed in the end walls of the cassette. When aligned, appropriate fasteners  54  can be positioned through securement areas  48 ,  50  or  52  and into securement area  46  to secure the inserts  14 ,  16  to the end walls at various positions.  
         [0050]    As seen in FIGS.  10 - 12 , the inserts may be secured at various positions relative to the end walls by the predetermined pattern of the securement areas  48 ,  50 ,  52  to accommodate disks of different diameter. Thus, inventory issues and cost issues are reduced by allowing a single universal cassette to be utilized which is reconfigurable by repositioning the inserts to accommodate different diameter of disks. For example, using securement areas  48 , the inserts are positioned as shown in FIG. 10 to accommodate a large diameter disk. Using securement areas  50 , the inserts are positioned as shown in FIG. 11 to accommodate a slightly smaller diameter disk. Using securement areas  52 , the inserts are positioned as shown in FIG.  12  to accommodate an even smaller disk. Thus, the cassette as illustrated can be reconfigured to hold disks having at least three different diameters, perhaps 95, 84 and 65 millimeter diameters. It should be appreciated that a cassette may have two or more predetermined positions and is not limited to three predetermined positions.  
         [0051]    In addition, and/or alternatively, substituting different inserts having differently configured or sized ribs  38  will allow the cassette to accommodate different thicknesses of disks or to accommodate pairs of disks in different orientations. For example, if the cassette is to be used during processing of single-sided disks, the ribs  38  could be configured as shown in FIG. 14 or  15  to accommodate gap merge disk pairs or contact merge disk pairs, respectively.  
         [0052]    For most processing applications, a cassette made from polybutylene terephthalate (PBT) plastic will be satisfactory. However, PBT plastic will not withstand the high temperatures associated with the sputtering process where temperatures can reach 350 degrees Celsius. In high temperature areas like this, polyesteresterketone (PEEK) will provide acceptable results, as will an entirely metal cassette. It may also be desirable to utilize an abrasion resistive plastic due to the constant movement of disks into and out of the cassette. Such a plastic is PEEK. Alternatively, an abrasion resistive plastic, such as teflon, may be added as an outer layer over a core material, such as stainless steel or aluminum alloys, providing the advantages of each material.  
         [0053]    Although the invention has been described with respect to specific embodiments, the details thereof should not be construed as limitations. It will be apparent that various different embodiments, changes and/or modifications may be resorted to without departing from the spirit and scope of the invention. For example, the exact number of securement areas on each end wall may vary. While the drawings illustrate three, there may be as few as two or as many as will fit on the end wall of the cassette. Also, the number of disks within a cassette may vary by varying the exterior size of the cassette. Moreover, as previously noted, it may be desirable in certain circumstances to make the cassette from metal, such as stainless steel or aluminum alloys. Thus, it should be understood that such variations and other equivalent embodiments are intended to be included within the scope of this invention.  
         [0054]    The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. Thismethod ofdisclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention.  
         [0055]    Moreover, though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g. as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.