Abstract:
A cassette system for disks to be manufactured into hard disks for computer memory storage includes a pair of end portions and a pair of side wall portions spanning between the end portions, defining a disk receiving region. The side wall portions together define a plurality of axially aligned slots for holding the disks. At least one of the end portions includes a test disk receiver, which may be a slot or pocket.

Description:
RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. Provisional Patent Application No. 60/556,848, entitled DISK CASSETTE SYSTEM and filed on Mar. 26, 2004, hereby fully incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to disk carriers, and more specifically, to cassettes for processing and packaging computer hard drive disk substrates.  
       BACKGROUND OF THE INVENTION  
       [0003]     Substrate carriers configured for holding multiple hard disk substrates during fabrication and shipping are well known in the data storage device industry. Examples of such prior art carriers are described in U.S. Pat. Nos. 5,921,397; 5,704,494; 4,669,612; and 5,348,151, each of which is hereby fully incorporated herein by reference.  
         [0004]     During processing of hard disks using known prior art carriers, a typical quality control practice involves designating one of the disks as a “test disk” for quality control inspection and lot identification. Testing may require the compromise or destruction of the test disk under examination. As a result, the yield of finished hard disks per batch is reduced at least by one disk, and the complexity of disk processing is increased due to post-processing tracking and handling of the designated test disk.  
         [0005]     Also, disk processing often involves the baking of the disks at temperatures of up to 300° C. or higher. Consequently, handling of the disk carrier during processing is generally automated. A relatively high degree of precision in carrier positioning is desirable to minimize disk damage and particulate generation from improper indexing of the robotic tooling. Prior art carriers, while offering a generally workable degree of precision in positioning, are still sometimes mispositioned, resulting in disk damage or excessive particulates in the processing environment.  
         [0006]     What is needed in the industry is a disk carrier that addresses the above-identified deficiencies in the prior art carriers.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention addresses the need in the industry for a disk carrier that enables simpler processing of test disks and improved accuracy in automated positioning. According to an embodiment of the invention, a cassette system for disks to be manufactured into hard disks for computer memory storage includes a pair of end portions and a pair of side wall portions spanning between the end portions, defining a disk receiving region. The side wall portions together define a plurality of axially aligned slots for holding the disks. At least one of the end portions includes a test disk receiver, which may be a slot or pocket.  
         [0008]     A further embodiment of the invention features a serrated flange on each of the side wall portions. These flanges may serve as a locating means for robotic or otherwise automated handling systems. The flanges are preferably configured asymmetrically to allow for the positive position sensing of the first disk.  
         [0009]     A feature of an embodiment of the invention is the inclusion of a test disk receiver in one or both of the end frames for the insertion of a test specimen. The test disk receiver, which may be a pocket or slot, is preferably dimensioned to fit within the constraints of the cassette end portion.  
         [0010]     An advantage of the end portion with test disk receiver according to the invention is that the test specimen eliminates the need for the designation of a processed hard disk for testing.  
         [0011]     An additional feature of an embodiment of the invention is that the test disk may be of any configuration or geometry, thus readily discernable from the disks in process.  
         [0012]     A further embodiment provides for the insertion of a test disk inserted in both of the cassette end portions. By providing two test disks, the confidence of the quality assessment can be improved by conducting tests on two samples if desired, without destroying otherwise valuable product.  
         [0013]     An additional feature and advantage of the present invention is that the overall dimensions of the disk carrier remains unchanged, so that the number of disks processed in an industry standard base footprint remains the same.  
         [0014]     Other objects and advantages of the present invention will be apparent to those skilled in the art upon reviewing the description, drawings and claims herein. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a top perspective view of a disk carrier according to an embodiment of the invention;  
         [0016]      FIG. 2  is a top plan view of the disk carrier of  FIG. 1 ;  
         [0017]      FIG. 3  is a top perspective view of an alternative embodiment of a disk carrier according to the invention;  
         [0018]      FIG. 4  is a front view of a test disk according to an embodiment of the invention;  
         [0019]      FIG. 4A  is an edgewise view of the test disk of  FIG. 4 ;  
         [0020]      FIG. 5  is a front view of a test disk according to an alternative embodiment of the invention;  
         [0021]      FIG. 5A  is an edgewise view of the test disk of  FIG. 5 ;  
         [0022]      FIG. 6  is a bottom perspective view of a disk carrier according to an embodiment of the invention;  
         [0023]      FIG. 7  is cross-sectional view of the disk carrier of  FIG. 2  taken at section  7 - 7 ;  
         [0024]      FIG. 8  is a bottom plan view of an embodiment of a disk carrier according to the invention;  
         [0025]      FIG. 9  is a side elevation view of the disk carrier of  FIG. 8 ; and  
         [0026]      FIG. 10  is an end elevation view of the disk carrier of  FIG. 8 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]     As depicted in  FIGS. 1-3 , a disk carrier  10  according to an embodiment of the invention generally includes end structures  12 ,  14 , and sidewalls  16 ,  18 , which are arranged to define a generally rectangular disk receiving region  20  with an open bottom  21  to enable processing fluids to readily circulate around disks disposed in disk receiving region  20 . Each of sidewalls  16 ,  18 , has a plurality of ribs  22  oriented facing inwardly into disk receiving region  20  and arranged to form a plurality of slots  24 . Each slot  24  is dimensioned to receive a single hard disk (not depicted), so that multiple hard disks may be held in disk carrier  10  in a spaced apart, axially aligned arrangement. Each sidewall  16 ,  18 , may further include a lower stand-off skirt portion  26  presenting a depth dimension annotated “D” in the drawings. Depth dimension D may be selected so as to be sufficient to enable hard disks received in slots  24  to remain in position when bottom edge  28  of disk carrier  10  is set on a surface. Further, lower stand-off skirt portion  26  may include centering notch  30  to enable positive positioning of the disk carrier  10 .  
         [0028]     Referring to  FIGS. 2 and 3 , in an embodiment of the invention, outer edges  32 ,  34 , of upper flanges  36 ,  38 , of sidewalls  16 ,  18 , may include multiple laterally projecting serrations  40 , which may function as an indexing and locating means during automated handling of disk carrier  10 . Preferably, serrations  40  extend the full length of outer edges  32 ,  34 , between end structures  12 ,  14 , to enable positive automated location and identification of the first slot  24  adjacent each end structure  12 ,  14 .  
         [0029]     End structures  12 ,  14 , are spaced apart and positioned at opposing ends of sidewalls  16 ,  18 . One or more apertures  42  may be provided in top surface  44  of each end structure  12 ,  14 , for receiving a carrying device (not depicted) to enable robotic transport of disk carrier  10 . Index structures  46 , which may be apertures or holes, are provided on end structure  14  to enable automated differentiation of end structures  12 ,  14 . Each end structure  12 ,  14 , may have a radiused cutout  48 , with an outwardly facing relieved portion  50  for receiving a cover (not depicted). Disk carrier  10  may be fitted with both a top cover and a bottom cover, as described in U.S. Pat. No. 4,557,382, hereby fully incorporated by reference herein.  
         [0030]     According to an embodiment of the invention, at least end structure  12  includes a test disk receiver  52 , which may be configured as a slot or pocket  54 . It will be appreciated that the geometry and dimensions of pocket  54  may be selected so as to accommodate any desired shape or size of test disk, which need not be of the same dimensions or geometry as the disks under process in slots  24 . Slot or pocket  54  may be integral with end structure  12  as depicted in  FIG. 1 , or may be defined as a recess in end structure  12  covered with a separate cover piece (not depicted). In another alternative embodiment, slot or pocket  54  may be defined in an entirely separate structure, which is then affixed to end structure  12  using any means of sufficient strength and durability to withstand the processing environment of the hard disks. In a still further alternative embodiment, slots or pockets  54  may be provided in both end structures  12 ,  14 , using any of the described configurations.  
         [0031]     Disk carrier  10  may be made from any material or combination of materials suitable for the processing environment. The preferred material is aluminum, which is forged or machined to the desired dimensions and tolerances, but alternatively, other metals may be used, as well as polymers or thermoplastics such as polyetheretherketone (PEEK) as temperatures permit.  
         [0032]     An exemplary configuration of a test disk  56  for use with an embodiment of disk carrier  10  is depicted in  FIGS. 4 and 4 A. Test disk  56  generally includes a planar body  57  having an upper portion  58 , a lower portion  60  and presenting a periphery  62 . Periphery  62  is generally arcuate in shape, with upper portion  58  having a first radius dimension annotated in  FIG. 4  as “A”, and with lower portion  60  having a relatively smaller radius dimension, annotated in  FIG. 4  as “B.” At the intersection of upper portion  58  and lower portion  60 , the difference in radius defines a pair of shoulders  64 ,  66 . A linear portion  68  running generally parallel to a horizontal disk axis C-C through the centers of radii A and B is preferably defined in periphery  62  at each of shoulders  64 ,  66 .  
         [0033]     In use, lower portion  60  of test disk  56  is inserted in pocket  54  of disk carrier  10 . Pocket  54  is dimensioned so that linear portions  68  contact top surface  44  of end portion  12 . Test disk  56  is thereby supported in pocket  54  on shoulders  64 ,  66 , with upper portion  58  extending upwardly from top surface  44  so as to be readily exposed to the processing fluids.  
         [0034]     An alternative embodiment of a test disk  70  is depicted in  FIGS. 5 and 5 A. Test disk  70  generally includes a planar body  72  having an upper portion  74 , a lower portion  76  and presenting a periphery  78 . Periphery  78  is again generally arcuate in shape, however, in this embodiment, upper portion  74  is configured as a disk with a first radius dimension annotated in  FIG. 5  as “B”, and lower portion  76  is configured as a tab extending from upper portion  74  and with a relatively larger radius dimension, annotated in  FIG. 5  as “A.” Lower portion  76  has a pair of opposing sides  80 ,  82 , which may be defined as generally parallel to a vertical axis of symmetry through test disk  70 .  
         [0035]     In use, lower portion  76  is inserted in pocket  54  of end portion  12 . In this embodiment, pocket  54  is dimensioned so that the radiused bottom edge  84  of lower portion  76  rests on the bottom of pocket  54 , thereby supporting the disk in place. As before, at least a portion of upper portion  74  extends upwardly from top surface  44  so as to be readily exposed to processing fluids.  
         [0036]     Although the depicted embodiments each include a test disk with a dual radiused periphery, any other configuration or geometric shape of test disk may be used within the scope of the present invention. In this regard, pocket  54  and/or the test disk may be made to conform each with the other in any desired shape, size or configuration.  
         [0037]     While only certain embodiments have been set forth in detail in the detailed description, other alternative embodiments and modifications within the scope of the present invention will be evident therefrom to those of skill in the art. Accordingly, the scope of the invention is not limited to the particular embodiments described, but only by the claims included herein.