Abstract:
Disclosed is a magnetic storage cartridge adapted to be removably received by a drive base. The magnetic storage cartridge comprises a housing that includes at least one magnetic disk rotatable about an axis, and an actuator arrangement pivotal about an axis. The actuator arrangement includes at least one read/write head for reading and writing information to and from the at least one magnetic disk. The housing also includes a first engagement feature positioned on the housing at the rotational axis of the magnetic disk and a second engagement feature positioned on the housing at the pivot axis of the actuator arrangement. The housing of the storage cartridge also includes a third engagement feature that is spaced from the first and second engagement features. The first, second and third engagement features adapted to be engaged by a corresponding first, second and third engagement features of the disk drive base to secure the magnetic storage cartridge to the disk drive base and substantially minimize performance degrading vibrations during operation of the magnetic storage cartridge.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This Non-Provisional Utility Patent Application claims the benefit of the filing date of U.S. Provisional Application Serial No. 60/212,040, filed Jun. 16, 2000, entitled “DISK DRIVE SYSTEM WITH ENCLOSED REMOVABLE CARTRIDGE OF VOICE COIL/HAD/DISK ASSEMBLY.” 
    
    
     TECHNICAL FIELD 
     This invention relates generally to disk drive storage systems. In particular, the present invention is a disk drive system with a removable and exchangeable cartridge incorporating magnetic media, head and voice coil assemblies. The disk drive system includes a plurality of mechanical engagement features arranged in a triangular pattern for engaging the removable cartridge and preventing movement of the cartridge during operation of the disk drive system. The mechanical engagement features supporting adaptive magnetic and electrical engagement features which enable operation of the disk drive system. 
     BACKGROUND OF THE INVENTION 
     Disk drive systems of the “Winchester” type are well known in the industry. A disk drive system of this type typically includes a head disk assembly and a printed circuit board (PCB) assembly for controlling operation of various components of the head disk assembly. The head disk assembly generally includes an enclosure which houses a magnetic disk arrangement, a magnetic transducer arrangement, a rotary actuator arrangement and a spindle motor arrangement. The magnetic disk arrangement is defined by one or more rigid disks coated with a magnetizable medium for storage of digital information in a plurality of circular, concentric data tracks. The disks are driven (i.e., rotated) by the spindle motor arrangement to spin, and thereby cause the surfaces of the disks to pass under respective read and write transducers of the magnetic transducer arrangement. The read and write transducers write information to and read information from the concentric data tracks in the disk surfaces of the rigid disks. There is typically one read and write transducer for each recording surface of each rigid disk. 
     The rotary actuator arrangement moves the read and write transducers from track to track cross the surfaces of the rigid disks under control of circuitry. The rotary actuator arrangement typically includes a permanent-magnet arrangement, a pivot bearing cartridge and a head stack assembly. The pivot bearing cartridge includes a stationary shaft secured to the enclosure to define an axis of rotation for the head stack assembly. The head stack assembly, often referred to as an “E-block” includes a flex circuit assembly, a voice coil and track accessing arms. Each one of the read and write transducers is secured to a respective one of the track accessing arms. During use, circuitry causes current to conduct through the voice coil, and because the voice coil lies in the magnetic field provided by the permanent-magnet arrangement, a torque is applied to the head stack assembly. The amount and direction of that torque is subject to control by a servo system that controls the rotary position of the read and write transducers relative to tracks on the respective recording surfaces of the rigid disks. Track accessing is limited to a certain range of disk tracks from an inner radius to an outer radius of the rigid disks by limiting the pivotal movement of the head stack assembly via a set of crash stop assemblies. 
     In a standard “Winchester” disk drive system, all the major sub-components, including the PCB assembly, rigid disks, the head stack assembly, the read and write transducers, the permanent magnets, the spindle motor, and crash stop assemblies are all mounted onto a drive base and cover that defines the enclosure. This enclosure is sealed to provide a relatively contaminant-free interior for these sub-components. Because of the need to maintain this contaminant free environment within the enclosure, these sub-components, particularly the disks, are not readily removable from the disk drive system enclosure. 
     The disk drive system, which includes the enclosure and sub-components, is typically rigidly mounted to a computer system housing so as not to be removable from the computer housing and therefore, so as not to be exchangeable with other disk drive systems, even of the same type. However, there are some disk drive systems that are meant to be readily removable and exchangeable. In either case during operation it is necessary that for the disk drive system to be rigidly mounted to the computer housing in a fixed position so as to prevent any “play” (i.e., movement) of the disk drive system. This “play”, whether side-to-side or up-and-down, is caused by vibration as a result of operation of other systems within the computer housing and/or operation of the sub-components within the disk drive system itself. This vibration can be due to or cause undesirable imbalances in the magnetic disk arrangement because of the high rotational speeds of the rigid disks. In addition, this vibration can be due to or cause undesirable imbalances in the rotary actuator arrangement which can cause actuator tracking problems that can result in the actuator arrangement taking longer to find the desired track on a rigid disk. As such, vibration causing “play” can degrade the overall performance of the disk drive assembly. Hence, for proper operation of the disk drive system, it is necessary to rigidly mount the disk drive system to prevent unwanted “play”. Moreover, in the case where the disk drive system is designed to be readily removable and exchangeable, it is exceedingly necessary to rigidly secure the readily removable and exchangeable portion of the disk drive system against unwanted movement (i.e., “play”) during operation of the disk drive system. 
     One non-readily removable and non-readily exchangeable “Winchester” disk drive system as described above is disclosed in U.S. Pat. No. 4,317,146 to Gervais et al. In Gervais et al., in contrast to what is described above, a stepper motor rather than a voice coil is used to actuate the track accessing arms of the head stack assembly. 
     The U.S. Pat. No. 5,235,481 to Kamo et al., discloses a readily removable and exchangeable disk drive system. In Kamo et al., a separate cartridge, which houses a disk/hub assembly, a head/arm assembly with a pivot, and a polarized magnet assembly, is readily removable from its drive and exchangeable with other drives. However, in Kamo et al., the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance. 
     The U.S. Pat. No. 4,359,762 to Stollorz discloses a readily removable and exchangeable disk drive system. In Stollorz, a separate storage module, which houses a disk/hub assembly and a head/arm assembly, is readily removable from its drive module so as to be exchangeable with other like drive modules. In Stollorz an external linear screw translation system drives and controls the head arm assembly. However, in Stollorz, like Kamo et al., the separate storage module is not adequately rigidly secured within the drive module so as to prevent vibration causing degradation in disk drive performance. 
     The U.S. Pat. No. 5,214,550 to Chan discloses a readily removable and exchangeable disk drive system similar to Kamo et al. As such, like Kamo et al. and Stollorz, the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance. 
     The U.S. Pat. Nos. 4,974,103; 4,965,691; and 5,175,657 to Iftikar discloses a readily removable and exchangeable disk drive system. In Iftikar a separate cartridge encloses transducer heads, a disk and its spindle translator, and one or more of actuators, either voice coil or magnets. The edges of the separate cartridge are locked in position via a pair of tracks in the drive housing&#39;s interior with the separate cartridge&#39;s middle portion suspended in the air. The rotation of the disk spindle inside the cartridge is actuated by a rotating magnetic field generated by a fixed coil assembly distanced from the cartridge&#39;s disk spindle. Such a rotating magnetic field not only would induce the rotation of the disk spindle, but also unwanted vertical and horizontal vibrations of the separate cartridge. These vibrations can lead to many technical problems such as recording track mis-registration, modulation and noise which are critical to high density, high performance recording. Also, a connector connecting the electronic components inside the removable cartridge to the drive base system lack essential features for preventing static electrical charges which can be very damaging to the read/write heads and the pre-amplifier chip. 
     The U.S. Pat. No. 5,694,267 to Morehouse et al. discloses a readily removable and exchangeable disk drive system. In Morehouse et al., a separate cartridge, which houses a disk/hub assembly, a head/arm assembly is readily removable from its drive and exchangeable with other drives. While the disk media, when not used, are mechanically enclosed inside the cartridge via a shutter system similar to a floppy disk, cartridge shuttering during loading and unloading of the cartridge can generate particles and thereby contaminate the cartridge and the head/disk interfaces. As such, when the drive operates, the disk assembly, along with the heads, are exposed to the drive environment and airflow inside the cartridge is not properly shrouded so as to prevent turbulence which can negatively affect the seeking and tracking performance of the transducer heads. In addition, the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance. 
     There is a need for improved disk drive systems. In particular, there is a need for a disk drive system that includes a readily removable and exchangeable magnetic disk drive cartridge, housing a disk/hub assembly and a head/arm assembly, with the disk drive cartridge being adequately rigidly secured within the drive housing so as to prevent vibration causing degradation of disk drive performance. Moreover, the disk drive cartridge should be adequately sealed to prevent contamination by particles and other contaminants that can adversely affect performance. In addition, the disk drive cartridge should prevent air turbulence which can negatively affect the seeking and tracking performance of the transducer heads. 
     SUMMARY OF THE INVENTION 
     The present invention is a magnetic storage cartridge adapted to be removably received by a disk drive assembly. The magnetic storage cartridge comprises a housing that includes at least one magnetic disk rotatable about a first axis, and an actuator arrangement pivotal about a second axis. The actuator arrangement includes at least one read/write head for reading and writing information to and from the at least one magnetic disk. The housing also includes a first engagement feature positioned on the housing at a vibration source. The first engagement feature adapted to be engaged by a first corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge. 
     In one aspect of the present invention, the housing further includes a second engagement feature positioned on the housing at a further vibration source. The second engagement feature is adapted to be engaged by a second corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge. The first engagement feature is coincident with the first axis and the second engagement feature is coincident with the second axis. In a further aspect of the present invention, the housing further includes a third engagement feature. The third engagement feature is adapted to be engaged by a third corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge. This third engagement feature is spaced from the first and second axes. In this further aspect of the present invention, the first, second and third engagement features are arranged in a triangle. 
     In another embodiment, the present invention provides a magnetic storage cartridge adapted to be removably received by a disk drive assembly. The magnetic storage cartridge comprises a housing that includes at least one magnetic disk and an actuator arrangement. The magnetic disk includes information critical to operation of the magnetic storage cartridge. The actuator arrangement includes at least one read/write head for reading and writing information to and from the at least one magnetic disk. The at least one read/write head upon insertion of the magnetic storage cartridge into the disk drive assembly accesses the information critical to operation of the magnetic storage cartridge to insure proper operation of the magnetic storage cartridge. 
     In a further embodiment, the present invention provides a disk drive assembly for removably receiving a magnetic storage cartridge having a first major surface and an opposite second major surface. The disk drive assembly comprises a housing configured for receiving the magnetic storage cartridge. The housing includes a first member, and a second member movable relative to the first member. The first and second members have an undocked state, wherein the second member is spaced from the first member by a first distance and the magnetic storage cartridge can be inserted to and removed from the housing, and a docked state, wherein the second member has been moved towards the first member so as to be spaced from the first member by a second distance less than the first distance, and wherein the first and second members engage the first and second major surfaces of the magnetic storage cartridge to secure the magnetic storage cartridge within the housing to permit operation of the magnetic storage cartridge. 
     In one aspect of this further embodiment, both the first and second members are movable. These first and second members are movable linearly in a direction substantially perpendicular to the first and second major surfaces of the magnetic storage cartridge. In a further aspect of this further embodiment, the first member is linearly movable in a first direction and the second member is linearly movable in a second direction substantially perpendicular to the first direction. In still a further aspect of the present invention, the first and second members are pivotally movable. 
     By engaging and securing the magnetic storage cartridge at its primary sources of vibration, the readily removable and exchangeable magnetic storage cartridge is rigidly secured within the base drive housing so as to substantially minimize vibrations that may cause a degradation in disk drive performance. In particular, the upper and lower plates of the base drive engage the magnetic storage cartridge at the rotational axes of the magnetic disk and the actuator arrangement as well as a third point to ensure a stable and secure mounting arrangement for the readily removable and exchangeable magnetic storage cartridge. Moreover, this mounting arrangement helps reduce the noise level of the magnetic storage cartridge, and helps absorb undesirable heat due to the rotation of the magnetic disk by conducting this heat out of the cartridge and to the upper and lower plate members. This mounting arrangement also allows the magnetic storage cartridge to be adequately sealed to prevent contamination by particles and other contaminants that can adversely affect performance. In addition, sealing of the magnetic storage cartridge substantially minimizes air turbulence which can negatively affect the seeking and tracking performance of transducer heads. Lastly, by pre-writing operational information related to the magnetic storage cartridge to the magnetic disk, or an enclosed semiconductor memory chip, this pre-written operational information can be accessed to achieve the optimal read/write and error-rate performance particular to the magnetic storage cartridge accepted by the base drive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate the embodiments of the present invention and together with the description serve to explain the principals of the invention. Other embodiments of the present invention and many of the intended advantages of the present invention will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof, and wherein: 
     FIG. 1 is a perspective of a complete disk drive system with a readily removable and exchangeable magnetic storage cartridge, enclosing a voice coil/head/disk assembly, being translated into a drive base by way of a loading mechanism in accordance with a preferred embodiment of the present invention. 
     FIG. 1 a  is a perspective view similar to FIG. 1 of a further embodiment of the loading mechanism for translating the magnetic storage cartridge into and out of the drive base in accordance with the present invention. 
     FIG. 1 b  is a perspective view similar to FIG. 1 a  of another embodiment of the loading mechanism for translating the magnetic storage cartridge into and out of the drive base in accordance with the present invention. 
     FIG. 1 c  is a perspective view of still another embodiment of the loading mechanism for translating the magnetic storage cartridge into and out of the drive base in accordance with the present invention. 
     FIG. 2 is perspective view of the embodiments of FIGS. 1,  1   a ,  1   b  and  1   c  illustrating the disk drive system with the magnetic storage cartridge fully engaged with the drive base in a desired engagement configuration for magnetic recording/retrieving operation in accordance with the present invention. 
     FIG. 2 a  is an exploded perspective view of the disk drive system illustrated in FIG.  2 . 
     FIG. 3 is a perspective view of the magnetic storage cartridge, with its cover and base detached, in accordance with the present invention. 
     FIG. 4 a  is a top plan view of the magnetic storage cartridge of the present invention with its cover partially cut off and removed. 
     FIG. 4 b  is a top plan view of the magnetic storage cartridge of the present invention cartridge with its cover removed illustrating the read/write heads flying above the disk surfaces. 
     FIG. 4 c  is a top plan view of the magnetic storage cartridge of the present invention with its cover removed illustrating the read/write heads unloaded and locked onto a set of load/unload ramps. 
     FIG. 4 d  is a top plan view of the magnetic storage cartridge with the cover removed illustrating an alternative system with the read/write heads parked on the disk surfaces at an inner radius at a contact-stop-start mechanism. 
     FIG. 4 e  is a top plan view of the base member of the magnetic storage cartridge of the present invention with the voice coil/head/disk assembly removed. 
     FIG. 4 f  is a bottom plan view of the base member of the magnetic storage cartridge with the cover and voice coil/head/disk assembly removed showing a shield shutter for an electrical connector. 
     FIG. 4 g  is an enlarged partial view of the shield shutter shown in FIG. 4 f.    
     FIG. 4 h  is a partial cross sectional view taken along line B—B in FIG. 4 g  illustrating the shield shutter and connector arrangement in accordance with the present invention. 
     FIG. 5 is a top plan view of the cover of the magnetic storage cartridge in accordance with the present invention. 
     FIG. 6 is a partial cross sectional view of a disk spindle assembly inside the magnetic storage cartridge and a motor spindle engaging system mounted to drive base in accordance with the present invention. 
     FIG. 6 a  is a partial plan view of the disk spindle assembly and the motor spindle engaging system shown in FIG.  6 . 
     FIG. 6 b  is a partial cross sectional view similar to FIG. 6 illustrating engagement features of the loading mechanism engaged with the magnetic storage cartridge at the rotational axis of the magnetic disk. 
     FIG. 6 c  is a partial cross sectional view illustrating engagement features of the loading mechanism engaged with the magnetic storage cartridge at the pivot axis of the actuator arrangement. 
     FIG. 7 is a partial cross sectional view of the magnetic storage cartridge and upper and lower plates of the loading mechanism shown through the axis of disk spindle, the spindle-translation interface, and the motor spindle. 
     FIG. 7 a  is a partial cross sectional view of magnetic engagement of a rounded corner of the magnetic storage cartridge with the external polarized magnets of the drive base, showing the relative configuration of the voice coil, the metal corner frame and the pivot assembly of the actuator arrangement. 
     FIG. 8 is a schematic representation of the electrical circuits inside the disk drive system. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A preferred embodiment of a disk drive system  999  including a drive base  990  and a readily removable and exchangeable magnetic storage cartridge  100  in accordance with the present invention is illustrated generally in FIG.  1 . The drive base  990  includes a housing  992  (shown in dashed lines for clarity) that encloses a permanent magnet rack assembly  400 , a print circuit board assembly (PCBA)  900 , and a cartridge loading/unloading assembly  700 . The cartridge loading/unloading assembly  700  is defined by an upper plate  500 , a lower plate  300 , and a translation mechanism  750 . 
     As seen in FIG. 2 a , in several embodiments of the present invention illustrated in FIGS. 1,  1   a ,  1   b  and  1   c , the permanent magnet rack assembly  400  is defined by an upper rack member  400   a  and a lower rack member  400   b . The upper and lower rack members  400   a  and  400   b  are secured together by a plurality of threaded fasteners  410  so as to define a single unitary structure. As seen in FIG. 1, the unitary rack assembly  400 , formed by the upper and lower rack members  400   a ,  400   b  defines a first wide slot  402  and a second narrow slot  404  for receipt and support of first and second end edges  102  and  104  of the magnetic storage cartridge  100 . The difference in the size of the first and second slots  402  and  404  insures that the magnetic storage cartridge  100  is insert into the rack assembly  400  in the correct orientation. As seen in FIG. 2 a , each rack member  400   a ,  400   b  includes a polarized magnet  420  whose purpose will be made clear below. In an alternative embodiment of the invention, only a single magnet  420  is mounted on either one of the rack members  400   a ,  400   b . In the preferred embodiment, the storage cartridge  100  is inserted to and removed from the rack assembly  400  manually by a user. Alternatively, the storage cartridge  100  is inserted to and removed from the rack assembly  400  by an electric-mechanical linear translation mechanism  720  (shown in dashed lines). In one preferred embodiment the upper and lower rack members  400   a ,  400   b  are made of metal, such as aluminum or steel. 
     In the preferred embodiment illustrated in FIG. 1, the upper plate  500  is linearly movable in the direction of double headed arrow  502 , and the lower plate  300  is linearly movable in the direction of double headed arrow  504  via operation of the translation mechanism  750 . The translation mechanism  750  in one preferred embodiment includes a plurality of stepper motors  752  that power drive screws  754  that engage brackets  756  secured to the upper and lower plates  500 ,  300  to move the plates  500 ,  300  between an undocked state, wherein the lower plate  300  is spaced from the upper plate  500  by a first distance (see FIG. 1) and the magnetic storage cartridge  100  can be inserted to and removed from the rack assembly  400 , and a docked state, wherein the upper and lower plates  500 ,  300  have been moved towards one another so that the upper and lower plates  500 ,  300  are spaced from one another by a second distance (see FIG. 2) less than the first distance, and wherein the upper and lower plates  500 ,  300  engage first and second major surfaces  106  and  108  of the magnetic storage cartridge  100  to secure the magnetic storage cartridge  100  within the rack assembly  400  to permit operation of the magnetic storage cartridge  100 . In particular, to engage the cartridge  100 , the upper plate  500  is moved downwards and the lower plate  300  is moved upwards. To disengage the cartridge  100 , the above process is simply reversed. Alternatively, the upper and lower plates  500 ,  300  can be moved manually by a user to completely engage and disengage the cartridge  100  placed within the rack assembly  400 . Other embodiments of the present invention include any modification or extension from the aforementioned. One of such modification is that the cartridge  100  can be inserted to and removed from the rack assembly  400  from an end or the back side of the housing  952  of and the drive base  990 , instead of from the side as illustrated in FIG.  1 . 
     FIG. 1 a  illustrates an alternative embodiment translation mechanism  750   a  for loading and unloading the cartridge  100  to and from the rack assembly  400 . In this alternative translation mechanism  750   a  the cartridge  100  is first engaged with the upper plate  300 , and is then linearly translated together with the upper plate  300  into the drive base rack assembly  400  and then the bottom of the cartridge  100  is engaged by the drive base lower plate  500  as the lower plate  500  is moved upwards. 
     FIG. 1 b  illustrates a further alternative embodiment translation mechanism  750   b  for loading and unloading the cartridge  100  to and from the rack assembly  400 . In this further alternative translation mechanism  750   b , the cartridge  100  is first engaged with the lower plate  500 , and is then linearly translated together with the lower plate  500  into the drive base rack assembly  400  and then the top of the cartridge  100  is engaged by the drive base upper plate  300  as the upper plate  300  is moved downwards. 
     FIG. 1 c  illustrates another alternative embodiment translation mechanism  750   c  for loading and unloading the cartridge  100  to and from the rack assembly  400 . In this another alternative translation mechanism  750   c , the cartridge  100  is first placed into the rack assembly  400  of the drive base  990 . Then the lower plate  500  and upper plate  300  plate of the drive base  990  are rotated, centered at two separated axes but in parallel, to engage with the cartridge  100 . 
     As seen in FIG. 2 a , the cartridge  100  is placed into the rack assembly  400  with its rounded corner  101  sandwiched by the pair of polarized magnets  420  mounted to the magnet rack assembly  400 . The drive upper plate  500  and the lower plate  300  together sandwich the cartridge  100  on its top (i.e., first major surface  106 ) and bottom (i.e., second major surface  108 ). To substantially prevent movement of the cartridge  100  relative to the upper and lower plates  500 ,  300  and the rack assembly  400 , the upper plate  500  and the lower plate  300  each include a plurality of engagement features. As seen in FIG. 2 a , the upper plate  500  includes a first engagement feature or pin  525 , a second engagement feature or pin  562  and a third engagement feature or pin  563  which are arranged to define a triangle. The first engagement feature  525  is adapted to engage a first corresponding engagement feature or aperture  230  in the cover  200  (see FIG. 3) of the cartridge  100  (see FIG.  6 ). The first corresponding engagement feature  230 , and thereby the first engagement feature  525 , is coincident with the axis of rotation of the disk spindle  118  of the spindle assembly  140  of the magnetic disk  170  and a primary source of vibration of the cartridge  100 . The second engagement feature  562  is adapted to engage a second corresponding engagement feature or aperture  250  in the cover  200  (see FIG. 3) of the cartridge  100  (see FIG. 6 b ). As seen best in FIG. 3, the second corresponding engagement feature  250 , and thereby the second engagement feature  562 , is coincident with the pivot axis  158  of the voice coil/head/disk assembly  150  and a further source of vibration of the cartridge  100 . Lastly, the third engagement feature  563  is adapted to engage a third corresponding engagement feature or aperture  240  in the cover  200  (see FIG. 3) of the cartridge  100  (see FIG. 6 c ). The third corresponding engagement feature  240 , and thereby the third engagement feature  563 , is positioned outside of the surface area of the magnetic disk  170 . 
     As seen in FIG. 2 a , the lower plate  300  includes a spindle motor  321  having a spindle translator  320  emerging from the top surface of the lower plate  300 . The spindle translator  320  is releasably engageable with the spindle  118  of the spindle assembly  140  of the magnetic disk  170  of the cartridge  100 . A first engagement feature or spindle-docking device  325  of the lower plate  300  is concentric to the spindle translator  320  on the lower plate  300 . This spindle-docking device  325  (i.e., first engagement feature of the lower plate  300 ) is adapted to engage a first corresponding engagement feature or aperture  130  in the base  110  (see FIG. 4 f ) of the cartridge  100  (see FIG.  6 ). The first corresponding engagement feature  130 , and thereby the first engagement feature  325 , is coincident with the axis of rotation of the disk spindle  118  of the magnetic disk  170  and a primary source of vibration of the cartridge  100 . When the cartridge  100  is engaged by the upper and lower plates  500 ,  300  the disk spindle  140  of the cartridge  100  is firmly docked and connected mechanically with the spindle translator  320  which can transfer the rotational motion of the spindle motor  321  mounted onto the lower plate  300  of the drive base  990  to the magnetic disk  170 . The lower plate  300  also includes a second engagement feature or pin  362  and a third engagement feature or pin  363 . The second engagement feature  362  is adapted to engage a second corresponding engagement feature or aperture  150  in the base  110  (see FIG. 4 f ) of the cartridge  100  (see FIG. 6 b ). The second corresponding engagement feature  150 , and thereby the second engagement feature  362 , is coincident with the pivot axis  158  of the voice coil/head/disk assembly  150  and a further source of vibration of the cartridge  100 . Lastly, the third engagement feature  363  is adapted to engage a third corresponding engagement feature or aperture  140  in the base  110  (see FIG. 4 f ) of the cartridge  100  (see FIG. 6 c ). The third corresponding engagement feature  140 , and thereby the third engagement feature  363 , is positioned outside of the surface area of the magnetic disk  170 . When the upper and lower plates  500 ,  300  are engaged with the cartridge  100 , the first, second and third engagement features  525 ,  562 ,  563  of the upper plate  500  are coincident with the first, second and third engagement features  325 ,  362 ,  363  of the lower plate  300 . As can be seen in FIG. 2 a , the first, second and third engagement features  525 ,  562 ,  563  of the upper plate  500 , and the first, second and third engagement features  325 ,  362 ,  363  of the lower plate  300  are arranged in a triangle to secure the cartridge  100  to the drive base  990  in a stable and rigid manner. 
     Additional embodiments of this invention envision a reverse configuration in which the spindle translator  320 , the spindle motor  321  and the spindle-docking device  325  are built into the upper plate  500  of the drive base  990 . Correspondingly, the counterparts,  525 ,  562  and  563  are switched to the lower plate  300 . 
     As seen in FIGS. 2 a ,  4   g  and  4   h , a mother connection pad  380  on top of the lower plate  300  is engaged in electrical connection with an outlet interconnect pad  180  at the bottom of the cartridge  100 . The outlet interconnect pad  180  is covered and protected by a shielding shutter  280  prior to the cartridge-to-drive engagement and when the cartridge  100  is removed from the drive base  990 . Via the outlet interconnect pad  180 , direct electrical current can occur from the PCBA  900  to the voice coil  155  enclosed at the corner  101  of the cartridge  100 . Thus, the induced current originating from the magnet pair  420  can actuate the voice coil  155  for pivotal movement centered at the pivot  158  with the help of magnetic flux penetrating through the cover faces  202  over the voice coil  155  at the rounded corner  101  of the cartridge  100 . 
     FIG. 3 is a perspective view of the cartridge  100 , with its cover  200  and bottom case  110  detached, according to this invention. The bottom case  110  hosts the magnetic disk  170  mounted onto the disk spindle assembly  118 , the voice coil/head stack assembly  150  mounted at its pivot  158 . The cartridge cover  200  is mounted onto the bottom case  110  via three main mounting screw assemblies at the disk spindle  230 / 118 , the pivot  250 / 158  and the third engagement point  240  as well as a set of secondary screws  220 . 
     The corner part  202  at the rounded corner  101  of the cover  200  is either recessed so as to step down closer to the voice coil  155  or made flat with the rest of the top cover  200 . This corner part  202 , consisting of no ferromagnetic materials, directly interfaces with the magnets  420  of the rack assembly  400 . At the center of the corner part  102  includes a thin high magnetic permeable piece  202   a , shaped in accordance with the magnets  420  and to interface with the rest of the corner  102 . This thin piece  202   a  has differentially higher magnetic permeability than the rest of the corner part  202  and even the rest of cartridge  100  so as to allow high density magnetic flux from the magnets  420  to penetrate through the thin piece  202   a  so that the magnetic flux can interact with the voice coil  155  inside the cartridge  100 . The round corner  101  of the bottom case  110  is preferably framed with a stiff metal frame  110   a  made of non-ferromagnetic metal/alloy such as Aluminum, to increase the stiffness of the round corner  101 . 
     As seen in FIG. 3, alternatively, a central piece  215  can be molded/bonded to the surrounding piece  216  of the cover  200 . The central piece  215  is preferably made of special metal sheet that can shield both electrical discharge/interference and magnetic flux from encroaching on the interior cavities of the cartridge where the disk and the heads are hosted. The surrounding piece  216  is preferably made of carbon-filled plastic, which can shield electrical discharge in this embodiment. 
     FIG. 4 a  is a top plan view of the cartridge with its cover  200  partially cut off illustrating the cartridge  100  in operation inside the drive base  990 . Inside the cartridge  100 , a magnetic disk  170  is mounted onto the disk spindle  118 . Both the magnetic disk  170  and the spindle  118  rotate steadily relative to the cartridge  100  as the disk spindle  118  is engaged and powered by the spindle translation interface  325  and the spindle motor  321 . A pair of magnetic read/write heads  160  are loaded onto and are flying above the top and bottom surfaces of the disk  170 . On the disk surfaces, analog magnetic data can be written in and read out, through a set of conducting wires  164  bounded to a set of suspension beams  162  mounted onto swage-plates  163   a  of a set of load arms  163  of the voice coil/head stack assembly  150 . At the other end of the assembly  150 , a voice coil  155  is bonded firmly with its pair of wires  156  connected to a flexible printed circuit board or FPCB  146 , on which a pre-amplifier chip  145  is assembled. The conducting wires  164  from the head  160  carry read/write signals to the pre-amplifier  145 . A mini flex cable  141  of the cartridge transports both the read/write signals between the pre-amplifier chip  145  and the outlet interconnection pad  180 , and the direct currents between the voice coil  155  and the outlet interconnection pad  180  via its wires  156 . Another set of wires  136   a , bonded onto the bottom case  110 , transport direct current from the outlet interconnection pad  180  to a magnetic crash stop  136  which magnetically holds one side of metal arm  154  of the voice coil  155 . Another crash stop  137  together with the magnetic crash stop  136  at another end of a voice coil cavity  120  of the bottom case  110  restrains the movement of the voice coil  155  within a defined angle of rotation around the pivot  158  of the voice coil assembly  155 . Covering the top side of the outlet interconnect pad  180  is a desiccant-house assembly  185 . The desiccant-house assembly  185  hosts a desiccant  186  which absorbs moisture and organic solvent, and thus, controls the interior environment of the cartridge  100  once it is enclosed and in operation for its life time. Near the third location  240  of mechanical engagement with the upper and lower plates  500 ,  300  is a head load/unload ramp assembly  190  mounted via two screws  191 , 192  onto the bottom case  110  inside the cartridge  100 . The ramp  190  is for unloading and holding the read/write heads  160  during non-operation of the cartridge  100  and loading of the read/write heads  160  for commencement of operation of the cartridge  100 . On the far corner of the cartridge  100  opposite the outlet interconnection pad  180 , an air flow channel  187  is engraved on the bottom case  110  so that air flow passing the channel  187  is filtered by a re-circulation filter  188 . 
     FIG. 4 b  is top plan view of the cartridge  100  with its cover  200  removed with the cartridge  100  in operation inside the drive base  990  in accordance with the present invention. On the surfaces of the rotating disk  170 , there are two cylindrical regions where magnetic data can be written and retrieved. A narrow region  172  is particularly reserved for storing critical data on the cartridge itself, preferably near the most inner radius that the read/write heads  160  can access on the surfaces of the disk  170 . The other much bigger region  173  is available for storing and retrieving user-defined data. The critical data stored in the reserved region  172  are pre-written in when the cartridge  100  is assembled and tested prior to final enclosure and shipment for user application. The critical data can include, but is not limited to, an optimal set of read and/or write currents for each of the two head/disk surface combinations of one cartridge, a list of defects on each of the disk surfaces associated with their heads, and/or mechanical resonance frequencies of the voice coil/head stack/disk spindle assembly. This critical data insures optimal performance of the cartridge  100  and the drive base  990 . This critical data can be encoded to prevent access to the information by unauthorized users and/or to prevent use copying. An open circular cavity is engraved in the bottom case  110  of the cartridge to create a shrouding  175  for the disk  170  so that airflow adjacent to the disk  170  is stabilized and drag force/torque of the airflow is reduced. 
     FIG. 4 c  is a top plan view of the cartridge with its cover removed wherein the cartridge  100  has been removed from the drive base  990  and the read/write heads  160  are unloaded and locked onto a set of load/unload ramps  190 . When the drive  999  is ready to stop operating the hosted cartridge  100 , the voice coil  155  is moved to a far side of the voice coil cavity  120  such that the heads  160  are outside of the outer radius of the disk  170 . Meanwhile, a set of lifting tips  161  are ramped onto the load/unload ramps  190  so that the heads  160  are lifted off from the surfaces of the disk  170  and moved further away to the position where voice coil/head stack assembly  150  is locked by the crash stop  136 . Next, the motor spindle  321  ceases rotation to full stop, stopping rotation of the disk  170 , thereby allowing the cartridge  100  can be removed from the drive base  990 . 
     FIG. 4 d  is a top plan view of a cartridge  100  employing an alternative drive system. In FIG. 4 d , the cartridge  100  has been removed from the drive base  990  and the read/write heads  160  are parked on the disk surfaces at an inner radius of the disk  170  using a contact-stop-start mechanism, in accordance with the present invention. Instead of unloading the read/write heads  160  off from the surfaces of the disk  170 , the heads  160  are allowed to land on a dedicated region, or landing zone  171 , at the most inner radius the heads  160  can reach when the disk  170  spins down to full stop. The crash stop  136  can hold and lock the voice coil/head stack assembly  150  and thus, the keep the heads  160  steady when the cartridge is in a non-operating mode. 
     FIG. 4 e  is a top plan view of the cartridge base  110  with the voice coil/head/disk assembly  155  removed. Here, only the load/unload ramp assembly  190  is left inside the cartridge base  110 . In an alternative embodiment of this invention, a central piece  115  is molded/bonded to the surrounding piece  116  of the cartridge base  110 , which corresponding to the central piece  215  in FIG.  3 . The central piece  115  is preferably made of special metal sheet that can shield both electrical discharge/interference and magnetic flux from inferring with the interior cavities of the cartridge  100  where the disk  170  and the heads  160  are housed. The surrounding piece  116  is made of carbon-filled plastic, which can shield electrical discharge. On the opposite side of the cartridge base  110 , a mounting hole  180   a  is made for mounting the outlet interconnection pad  180  (see FIG. 4 d ) onto the base  110 . 
     FIG. 4 f  is a bottom plan view of the cartridge base  110  with the cover  200  and voice coil/head/disk assembly  150  removed for clarity. Here, the outlet interconnection pad  180  within the bottom case  110  is shield-covered by a metal shield shutter  280  which can shield the outlet interconnection pad  180  from external electrical-magnetic inference (EMI) and electrostatic discharge (ESD). When the cartridge  100  is translated into the drive base  990 , the metal shield shutter  280  is slidably opened by the drive along the shutter&#39;s sliding tracks  285 , so that the outlet interconnection pad  180  is exposed for contact connection. A rectangular-shaped recess  112  on the end  104  of the cartridge  100  together with end  102  of the cartridge  100  cooperate with the slots  402  and  404  to guide the sliding of the cartridge  100  into the drive base  990  as shown in FIGS. 1,  1   a ,  1   b , and  1   c , in only one direction and one configuration as illustrated in FIG.  2 . For example, the cartridge, if flipped upside down, cannot slide fully into the drive. 
     FIG. 4 g  is an enlarged view of the metal shield shutter  280  on top of the outlet interconnects pad  180 , while FIG. 4 h  is the cross-section of the shutter  280  and the interconnect pad  180 . When the cartridge  100  is not engaged with the drive, the shutter  280 , is pulled by the shutter pull-back spring  281  in the direction  281   a , which maintains the cover in a closed position covering and shielding the outlet interconnect pad  180  and the mounting hole  180   a . As the cartridge  100  is properly placed into the drive between the upper and lower plates, a shutter opener  390  of the lower plate  300  is driven into a shutter push-lock window  282  in the direction  391 . This action unlocks the shutter  280  from a shutter locker  283 , and drags (i.e., slides) the shutter  280  on the sliding tracks  285 , thus opening the mounting hole  180   a  to reveal the outlet interconnect pad  180 . 
     A preferred embodiment for engaging the mother connection pad  380  of the drive&#39;s lower plate  300  to the outlet interconnect pad  180  is illustrated in FIG. 4 h . As the shutter  280  is unlocked and dragged away from covering and shielding the mounting hole  180   a  and the outlet interconnect pad  180 , the mother connection pad  380  is driven along the trajectory  385  to clip or clamp connect with the outlet interconnect pad  180  of the cartridge from the cartridge&#39;s bottom. Here, the lips  181   a  of the metal pins  181  of the mother connection pad  180  are clamped or clipped onto the tongues  181   a  of the metal pins  181  of the outlet interconnect pad  180 . Thus, the mother connection pad  380  is in firm contact and good electrical connections with the outlet interconnect pad  180  are formed. As they are being disengaged, the mother connection pad  380  is moved in the reverse path of the trajectory  385  till they are properly disengaged. Once the shutter opener  390  is withdrawn in the reverse of the direction  391  and disengaged with the shutter lock window  282 , the shutter pull-back spring  281  pulls back the shutter  280  in the direction  281   a  to close the mounting hole  180   a  and to cover and shield the outlet interconnect pad  180 . The shutter locker  283  then locks the shutter  280  in place to cover and shield the mounting hole  180   a  and the outlet interconnect pad  180 . 
     FIG. 5 is a top view of the cartridge&#39;s cover  200  according to this invention. The surrounding piece  116  of the cover  200  has a corresponding recess  202  mirroring the recess  102  on the bottom of the bottom case  110 . However, it preferably does not have a rectangular-shaped recess similar to the recess  112  of the base; thus, a flipped cartridge can not slide fully into the drive. The figure also shows the preferable configuration of the three preferred docking locations, the disk spindle/docking hole  230 , the docking location/mounting screw at pivot  250 , and the third docking location  240 . 
     FIG. 6 is a cross-section side view of the disk spindle assembly  118  and spindle translator  320 . The disk spindle  43  is locked in position via the engagement feature  525  of the upper plate of the drive base  990  and the motor spindle interface  325  and the spindle  320 . The disk  170  is clamped by two spacers  46  and the disk clamp  47  onto the disk spindle  43  which can translate rotation of the motor spindle interface  325  and the spindle  320  to the clamped disk  170  at the same rotation speed. The bearing  42  can separate such rotation from the disk spindle top mount  41 , the mounting screw  49 , and the mounted cover  48 / 215  with the disk spindle, as well as the bottom case  45 / 115 ; thus, the cartridge remains steady while the disk  170  is rotating inside. 
     Another embodiment of this invention is any modification or variation of the above configuration of the motor-to-disk spindle engagement, such as one illustrated in FIG. 6 a . Such modification is made so the motor spindle interface  325  engages the disk spindle  43  inside the inner cylinder of the disk spindle  43 . Thus, the rest of the spindle translation interface, non-rotating part,  325 , can be firmly pressed onto the central metal piece  45 ( 115 ) of the cartridge&#39;s bottom case, thereby clamping the cartridge at the disk spindle  43  location with the engagement feature  525  (at the spindle) of the upper plate. This will help translate rotational motion smoothly from the drive&#39;s motor to the disk spindle  43 , and mechanically constrain undesired relative vertical and horizontal motions between the cartridge  100  and the drive base  990 . 
     FIG. 6 b  is a sectional view illustrating the second engagement features  562  and  362  of the upper and lower plates  500 ,  300  engaging the cartridge  100  at the pivot  158  of the voice coil/head stack assembly  150  as previously described. 
     FIG. 6 c  is a sectional view illustrating the third engagement features  563  and  363  of the upper and lower plates  500 ,  300  engaging the cartridge  100  at the corresponding engagement features  240 ,  140  as previously described. A compression seal ring  109  position between the base  110  and the cover  200  of the cartridge  100  seals the interior of the cartridge  100  from contaminants. 
     FIG. 7 is a cross-section view of the cartridge  100 , the upper and lower plates  500 ,  300  of the drive base  990  in operation mode through the vertically merged axis of disk spindle  118 , the spindle-translation interface  325 , and the motor spindle  320  according to this invention. The cross-section is taken in reference to FIGS. 2 and 4 a . As the upper plate  500  and the lower plate  300  engage with the cartridge  100 , the engaging feature  525  locks the cartridge at the spindle with the motor spindle interface  325  which also engages the disk spindle  43  upwards. Layers  505  and  305  are attached to the upper and lower plates  500  and  300 . These layers  505 ,  305 , are preferably made of vibration/noise absorbing/damping and/or heat absorbing materials, and firmly contact the cover  200 / 215  and the bottom case  110 / 115  of the cartridge. Thus, the level of vibration and noise generated inside the cartridge is reduced. 
     FIG. 7 a  is a cross-section view of magnetic engagement of the round corner  101  of the cartridge  100 , as shown in FIG. 2, with the external magnets  420  mounted to rack assembly  400  of the drive base  990 . This illustrates the relative configuration of the voice coil  155 , the metal corner frame  101   a  and the pivot assembly and docking as shown in FIG. 6 b , with the magnets  420  and a mounting frame  421  of the rack assembly  400 . The magnets  420  are in proximity engagement with the round corner  101  and emit magnetic flux which passes through the permeable, but non-ferromagnetic piece  202   a  with minimum loss of magnetic flux. This magnetic flux interacts with the voice coil  155  to induce an electric current. The magnets  420  are firmly mounted onto their respective mounting frame  421 , which also provides prevents residual magnetic flux from the magnet  420  from flowing in other directions than through the voice coil  155 . A non-ferromagnetic metal corner frame  101   a  is shown molded with the high permeable piece  102   a , stiffening the round corner  101  mechanically. 
     FIG. 8 is the schematic of the core embodiment in the electrical integration of the whole drive system  999  with the removable (memory) cartridge  100 . The PCBA  900  electrically engages the cartridge  100  via the cartridge&#39;s outlet interconnect pad  180  and the mother board connection pad  380  of the PCBA  900 . Thus, the voice coil  155  is connected with the servo controller of the drive  999  via the voice coil wires  156  and the mini flex cable  141 . In addition, the magnetic heads  160  and the preamplifier chip  145  and the ROM chip  145   a  are connected to the read/write channel of the drive  900 , via the conducting wires (cables)  164  and the mini flex cable  141 . Under the electro-mechanical control of the drive&#39;s SPM/Engage controller, the disk  170  and its spindle  140  are mechanically engaged with drive&#39;s spindle motor  325 / 320 . The drive&#39;s SPM/Engage controller also controls and coordinates all the other mechanical engagements of the drive  999  and its subsystems with the cartridge  100 . These include, locking the cartridge  100  firmly between the plates  500 ,  300  inside the drive base  990 , opening the metal shield shutter  280  (not shown in FIG. 8) and engaging the cartridge&#39;s outlet interconnect pad  180  and the mother board connection pad  380 . 
     Although specific embodiments have been illustrated and described herein for purposes of description of the preferred embodiment, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations calculated to achieve the same purposes may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. Those with skill in the chemical, mechanical, electro-mechanical, electrical, and computer arts will readily appreciate that the present invention may be implemented in a very wide variety of embodiments. For example, the dimensions of the circular disk, i.e. the inner and outer diameters as well as the thickness, are not limited to any particular standard dimensions, such as 3-½ inch diameter and 31 mil thick. Thus, the dimensions of all the other components of the drive and the cartridge are not limited to particular standards. The substrate of the disk is not limited to any particular type, such as Aluminum, glass or plastic. A head load/unload mechanism can also be employed at the inner diameter side of the disk inside the cartridge. Lastly but not least, a single magnet, rather than a pair of two facing magnets, can be employed and mounted onto one of the rack members of the drive base. This application is intended to cover any adaptations or variations of the preferred embodiments discussed therein. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.