U.S. patent application number 08/968223 was filed with the patent office on 2001-09-13 for low-profile miniature disk cartridge.
Invention is credited to BRAKEN, ALLEN T., MUSE, JAY A., SCHICK, BRIAN, THOMAS, FRED III.
Application Number | 20010021083 08/968223 |
Document ID | / |
Family ID | 25444640 |
Filed Date | 2001-09-13 |
United States Patent
Application |
20010021083 |
Kind Code |
A1 |
BRAKEN, ALLEN T. ; et
al. |
September 13, 2001 |
LOW-PROFILE MINIATURE DISK CARTRIDGE
Abstract
A disk cartridge for use in a miniature drive. The drive is
usable in a variety of small computer devices. As such it is
constrained in both height, width and length. Preferably, the drive
is of a PCMCIA size, preferably type II. The cartridge for use
therein is less than about {fraction (1/10)} inches high and less
than about 2 inches wide.
Inventors: |
BRAKEN, ALLEN T.; (LAYTON,
UT) ; MUSE, JAY A.; (CLEARFIELD, UT) ; SCHICK,
BRIAN; (EDEN, UT) ; THOMAS, FRED III; (OGDEN,
UT) |
Correspondence
Address: |
MICHAEL J. SWOPE
WOODCOCK WASHBURN KURTZ MACKIEWICZ
ONE LIBERTY PLACE
46TH FLOOR
PHILADELPHIA
PA
19103
|
Family ID: |
25444640 |
Appl. No.: |
08/968223 |
Filed: |
November 12, 1997 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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08968223 |
Nov 12, 1997 |
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08920932 |
Aug 29, 1997 |
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6134081 |
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08920932 |
Aug 29, 1997 |
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08746096 |
Nov 6, 1996 |
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Current U.S.
Class: |
360/133 ;
G9B/17.006; G9B/19.028; G9B/23.036; G9B/23.039 |
Current CPC
Class: |
G11B 17/028 20130101;
G11B 17/047 20130101; G11B 17/0282 20130101; G11B 19/2009 20130101;
G11B 17/0438 20130101; G11B 23/0316 20130101; G11B 17/0436
20130101; G11B 23/0035 20130101; G11B 23/0312 20130101 |
Class at
Publication: |
360/133 |
International
Class: |
G11B 005/82 |
Claims
What is claimed is:
1. A disk cartridge for use in a removable media disk drive, said
cartridge comprising: an outer shell having a driving access
opening and a head access opening, said outer shell having a
thickness less than about 0.10 inches and a width less than about 2
inches; a flexible media adapted for rotation within said drive; a
hub fixed to said media proximate the center thereof, said hub
being disposed in said driving access opening.
2. The disk cartridge as recited in claim 1, further comprising a
shutter for selective movement over said head access opening,
wherein said outer shell comprises sheet steel and wherein said
shutter comprises aluminum.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to a cartridge based data storage
system in which a flexible magnetic disk is disposed within a
cartridge shell. More particularly, the invention relates to a
low-profile miniature disk cartridge.
[0002] Microprocessors and supporting computer technologies are
rapidly increasing in speed and computing power while decreasing in
cost and size. These factors have led to the broad application of
microprocessors to an array of electronic products, such as
hand-held computers, digital cameras, cellular phones and the like.
All of these devices have, in effect, become computers with
particular application-specific attributes. For this new breed of
computer products, enormous flexibility is gained by the ability to
exchange data files and store computer software.
[0003] A variety of proprietary storage devices have been used in
computer products. For example, hand-held computers have used
integrated circuit memory cards ("memory cards") as the primary
information storage media. Memory cards include memory storage
elements, such as static random access memory (SRAM), or
programmable and erasable non-volatile memory, such as "flash"
memory. Memory cards each are typically the size of a conventional
credit card and are used in portable computers in place of hard
disk drives and floppy disk drives. Furthermore, memory cards
enhance the significant advantages of the size, weight, and battery
lifetime attributes of the portable computer and increase
portability of the storage media. However, because of the limited
memory density attainable in each memory card and the high cost of
the specialized memory chips, using memory cards in hand-held
computers imposes limitations not encountered in less portable
computers, which typically use more power-consuming and heavier
hard and floppy disk drives as their primary storage media.
[0004] Other of these computer products, such as the digital
camera, have employed miniature video disks as the storage media.
For example, U.S. Pat. No. 4,553,175 issued Nov. 12, 1985 to
Baumeister discloses a digital camera configured to store
information on a magnetic disk. In Baumeister, a signal processor
receives signals representative of a picture from a photo sensor.
Those signals are recorded on a magnetic disk for later processing.
Unfortunately, the video disk storage product provides limited
storage capacity. For that and other reasons (e.g., power
consumption and cost), the video disk has not been used in other
computer products. As a result, interchanging data from one of
these digital cameras with other computer products, such as a
hand-held computer, is not readily achieved.
[0005] Miniature hard disk drives have also been suggested for use
in portable computer products. For example, U.S. Pat. No. 5,469,314
issued Nov. 21, 1995 to Morehouse et al. discloses a miniature hard
drive for use in portable computer applications. In Morehouse, a
hard disk drive is described that is approximately 50 mm in
diameter. While addressing many of the problems presented by
storage requirements in portable computers, the obvious problem of
removability of the storage media is still present.
[0006] Similar to a standard size cartridge, the miniature
cartridge contains a flexible magnetic disk disposed within a hard
outer shell. Such a standard size cartridge is disclosed in U.S.
Pat. No. 4,445,157 (Takahashi). The Takahashi patent is generally
directed to a disk cassette that contains a flexible magnetic disk
having a center core (i.e., a hub) and an apparatus for reading and
recording information on the flexible magnetic disk. The disk
cassette comprises a flexible disk attached to a hub. The disk and
hub assembly are sandwiched between an upper cover and a lower
cover.
[0007] Thus, there is a need for an miniature disk cartridge for
use with portable devices.
SUMMARY OF THE INVENTION
[0008] In accordance with the present invention a mini-cartridge is
provided for mini drives in a plurality of hand-held devices which
generate signals representing different functions performed by
different classes of the devices. For example, the devices include
digital cameras, electronic books, global positioning systems,
personal digital systems, portable games and cellular phones. Each
of these devices has a mini drive for writing signals and reading
signals representing the functions to and from a magnetic medium in
the mini-cartridge. In this way, signals representing the diverse
functions performed by the different classes of devices are
recorded on the mini-cartridge. The hand-held devices incorporating
the present invention provide and create a single means of
capturing, moving and storing information across multiple
products.
[0009] The present invention is directed to a miniature data
storage device and disk cartridge for use in a drive. The drive is
usable in a variety of small computer devices. As such it is
constrained in both height, width and length. Preferably, the drive
is of a PCMCIA size, preferably type II. The cartridge for use with
the drive comprises an outer shell having a spindle access opening
and a head access opening. A substantially flexible medium is
rotatably disposed within the outer shell, and a hub is connected
to the medium proximate the center. The outer shell has a thickness
less than about 0.10 inches and a width less than about 2
inches.
[0010] The disk cartridge further comprising a shutter for
selective movement over the head access opening, The outer shell
comprises sheet steel and the shutter comprises aluminum.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing summary, as well as the following detailed
description of the preferred embodiments, is better understood when
read in conjunction with the appended drawings. For the purpose of
illustrating the invention, there is shown in the drawings an
embodiment that is presently preferred, it being understood,
however, that the invention is not limited to the specific methods
and instrumentalities disclosed. In the drawings:
[0012] FIG. 1 is a diagram of the interchangeable mini-cartridge of
the present invention, including a plurality of devices each having
a mini disk drive, and including a caddy to adapt the
mini-cartridge to a full-size drive of a host computer;
[0013] FIG. 2 is a top plan view of a disk drive according to the
present invention;
[0014] FIG. 3 is an isometric view of a cartridge for use with the
drive of FIG. 1;
[0015] FIG. 4 is a top plan view of the cartridge of FIG. 2;
[0016] FIG. 5 is a bottom plan view of the cartridge of FIG. 2;
[0017] FIG. 6 is a side elevation view of the cartridge of FIG.
2;
[0018] FIG. 7 is an exploded view of the cartridge of FIG. 2;
[0019] FIG. 8 is a partially exploded view of the cartridge of FIG.
2 showing an internal shutter shell subsystem;
[0020] FIG. 9 is a top plan view of the cartridge of FIG. 2 with
the upper shell half removed to reveal the operation of the shutter
shell;
[0021] FIG. 10 is another top plan view of the cartridge of FIG. 2
with the upper shell half removed to reveal the operation of the
shutter shell;
[0022] FIG. 11A-11E are illustration of the operation of shutter
shell 16 in conjunction with the drive of FIG. 2;
[0023] FIG. 12 is a bottom isometric view of the cartridge of FIG.
2 showing the lateral freedom of movement of the hub;
[0024] FIG. 13 is a cross section of the disk of FIG. 12 along the
lines 13-13;
[0025] FIGS. 14A-14D show cross sections of the cartridge and drive
of FIGS. 11A-11D along the lines 14-14 in various stages of
insertion the cartridge into a disk drive;
[0026] FIG. 15A shows an isometric view of the load ramp of the
present invention;
[0027] FIG. 15B shows the arms opened during media insertion to
prevent damage to the media;
[0028] FIG. 15C shows the arms closed after media is fully inserted
into the drive;
[0029] FIG. 15E shows the heads loaded onto the load ramp and
compressing a bias spring;
[0030] FIG. 16 is an isometric view of the interior of a shutter
shell and liner assembly showing the relative location of a media
distortion neutralizer.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0031] The present invention provides a data storage cartridge for
use with a removable media type of disk drive. Throughout the
description, a preferred embodiment of the invention is described
in connection with a particular sized and shaped disk cartridge.
However, the disk cartridge dimensions and shape are presented for
exemplary purposes only. Accordingly, the mechanism should not be
limited to the particular cartridge embodiment shown as the
invention contemplates the application to other cartridge and drive
types and configurations.
[0032] FIG. 1 shows a plurality of devices 100 which generate
signals representing different functions performed by different
classes of the devices. For example, the global positioning system
100a can generate signals representing navigational position.
Electronic book 100b, digital camera 100c, personal digital
assistant (PDA/Palmtop) 100d, portable game 100e, cellular phone
100f, and laptop computer 100g each generate signals representing
the function performed by that particular device. Each of these
devices has a miniature disk drive 50 for writing the signals and
reading the signals from a magnetic recording medium so that
diverse functions performed by different classes are recorded on
the devices, i.e. a drive 50a for global positioning system 100a, a
drive 50b for electronic book 100b, a drive 50c for digital camera
100c, a drive 50d for PDA/palmtop 100d, a drive 50e for portable
game 100e, a drive 50f for cellular phone 100f, and a drive 50g for
laptop computer 100g.
[0033] A mini-cartridge 10 has a magnetic recording medium on which
the signals from the devices are recorded. Mini-cartridge 10 is
compatible with the mini drives 50. Standard file formats maintain
compatibility between devices 100. In the preferred embodiment,
drives 50 are sized to fit within a PCMCIA form factor, preferably
PCMCIA type II or type III, more preferably type II. These form
factors is commonly used in portable personal computers. For
example, PCMCIA type II form factor is commonly used for a modem
connection of a notebook computer. PCMCIA type II form factor is
quite small so that miniature drive 50 readily fits into all of the
portable, hand-held devices shown in FIG. 1. The miniature drive 50
is insertable into and removable from the device just as the PCMCIA
modem is insertable into and removable from the PCMCIA slot of a
notebook computer. Alternatively, the drive 50 could be hard wired,
i.e., built-in, to the device. In both cases, the device generates
a digital function signal which is connected to the magnetic heads
of the drive so that the digital function signal can be written on
the magnetic medium of miniature cartridge 10. As an example, a
digital function signal representing a picture taken in a digital
camera 100c is recorded on a cartridge 10. This digital function
signal can then be read by other classes of devices when the
cartridge 10 is inserted into the respective other device.
[0034] FIG. 2 is a top view of a disk drive 50 with its top cover
removed for clarity. Drive 50 accepts a removable disk cartridge 10
(shown in phantom) for reading and storing digital information.
Drive 50 comprises a chassis 57, an actuator 56 (preferably a
rotary actuator), including an opposing pair of load beams 44
having a read/write head 54 disposed at the end of each load beam,
a load ramp 47, a spindle motor 53 and a spindle 40, and a shutter
opening arm (not shown). The operation of disk mounting to spindle
40 is described more fully below. A disk cartridge 10 can be
inserted into the front of the drive in the direction indicated by
the arrow. During insertion, cartridge 10 slides linearly along the
top surface of chassis 57 and spindle motor 53 for engagement with
the read/write heads 46.
[0035] FIGS. 3-6 are isometric, top plan, bottom plan, and side
elevation views of a miniature disk cartridge 10 that embodies
aspects of the present invention. Miniature disk cartridge 10 has a
number of differences from a full-size cartridges, such as the
well-known 1.44 megabyte 3.5" floppy disk cartridge and the
well-known ZIP disk cartridge) that prevent the miniature disk
cartridge 10 from operating directly in a full-size drive. Perhaps,
the most obvious of these differences is size. Disk cartridge 10
has a much smaller form factor than a full-size drive cartridge.
Whereas a full size drive cartridge is about 4" square and 1/4"
high, a mini-cartridge less than about 2" wide square and about
{fraction (1/10 )}" high. In particular, disk cartridge 10 has a
width w preferably in a range of about 49 (1.9") to 51 mm (2"),
most preferably about 50.1 mm, a length l about 50 to 52.5 mm long,
preferably about 51.8 mm, and a thickness h less than about 2 mm
(about {fraction (1/10)}") thick, most preferably 1.95 mm. A large
wedged shaped disk access opening 418 is disposed in the front
portion of disk cartridge 10 to provide selective access to the
media of cartridge 10. Disk cartridge 10 comprises a flexible
magnetic disk 14 (partially shown in FIG. 5) and a disk media hub
12. A driving access hole 218 provides an opening in cartridge 10
for drive spindle 40 (see FIG. 2) to engage hub 12 and drive
flexible disk 14 past opposing read write heads 54 (also shown in
FIG. 2). Hub 12 is sized slightly smaller than driving hole 218b,
and as best shown in FIG. 4, hub 12 projects downwardly from
cartridge 10. Cartridge 10 also has a side cut-out 34 and abutment
surface 35. As explained more fully below, cut-out 34 and abutment
surface 35 engage a sliding lever during cartridge insertion and
ejection. Cut-out 34 functions to retain cartridge 10 in drive 50
and ensure proper cartridge insertion while abutment surface 35
provides a flat surface for engagement and spring loading of
sliding lever.
[0036] Referring also to FIG. 7, an exploded view of cartridge 10
is provided to more clearly show cartridge 10 interior components.
Cartridge 10 comprises top and bottom cartridge shell halves 18a
and 18b, respectively, a rotary shutter shell having upper and
lower halves 16a and 16b, respectively, upper and lower shutter
shell liners 15a and 15b, respectively, a shutter pivot post 20, a
shutter spring mechanism 22, and a shell stabilizer 24.
[0037] Cartridge 10 is about half the thickness of the well-known
3.5 inch floppy disk. As a result convention removable cartridge
shell materials cannot be used to construct cartridge 10. Plastics,
such as those used in the well-known 3.5 inch floppy disk, would
either be too thick or not strong enough if manufactured with the
desired thickness. To manufacture a thin cartridge, such as
cartridge 10, all of the component materials must be as thin as
possible while providing structural support that will withstand the
rigors of everyday use. For example, cartridge shell halves 18a and
18b are formed from a thin sheet material preferably about 0.1854
mm thick. To provide the structural support, the shell is
preferably made from a sheet metal. Preferably the metal is sheet
steel, more preferably stainless steel, and most preferably series
300 stainless steel. Cartridge shell halves 18a and 18b are
preferably cut from a sheet of steel in a stamping operation which
forms the turned edge portions 118a and 118b, provides the cutouts
such as the driving hole 218b in the bottom cartridge shell half
18b, post hole 218a in the top cartridge shell half 18a, media
access openings 418a, 418b, and so on.
[0038] Shutter shell halves also must meet strict thickness
requirements. As such, shutter shell 16a and 16b are formed from a
thin sheet material. The sheet material is preferably a sheet
metal. The sheet metal is preferably thin sheet aluminum,
preferably 5052 aluminum, more preferably in a half-hard condition.
The sheet aluminum is preferably about 0.1854 mm thick. Shutter
shell halves are also preferably cut from a sheet of aluminum in a
stamping operation which forms upstanding rim 116a in top shutter
shell half 16a, upstanding rim 116b in the bottom shutter shell
half 16b, and cuts driving hole 316b in the bottom of shutter shell
half 16b, pivot hole 316a in the top shutter shell half 16a, and
media access openings 416a, 416b in shutter shell halves 16a and
16b.
[0039] Upper shutter shell half 16a has a media distortion
neutralizer 11 disposed on the inner surface 216a of shutter shell
half 16a. Distortion neutralizer 11 is located proximate the apex
region of wedge shaped opening 416a. As described in further detail
below, distortion neutralizer aids the planarity of media 14 as it
approaches head load ramps during disk cartridge 10 insertion into
drive 50. Distortion neutralizer provides a raised surface on upper
shutter half 16a. Preferably the distortion neutralizer is formed
directly on the surface of shutter half 16a, but could also be
formed as a separate piece and attached by glue, welding, or the
like.
[0040] Liners 15a and 15b are attached to shutter shell halves 16a
and 16b. Liner 15a is attached to inside surface 216a of shutter
shell half 16a; whereas liner 15b is attached to inside surface
216b of shutter shell half 16b. As described in detail below, disk
media 14 rotates within the shutter shell and not the cartridge
shell. Accordingly, unlike other known cartridges wherein the
liners are typically attached to the inside of the cartridge shell,
liners 15a, 15b are attached to the inside surface of shutter
shells 16a, 16b.
[0041] Liners 15a and 15b are preferably attached via an adhesive,
more preferably a pressure sensitive adhesive. Liners 15a and 15b
are cut to the shape of the surface to which they will be attached
(i.e., 216a, 216b) from a sheet of liner material. The liner
material is preferably 100% polyester, more preferably Veratec
141-620 available from Data Resources Group in Walpole Mass. The
liner material has a thickness preferably in the range of about
3.35 mils to about 3.8 mils, more preferably about 3.35 mils.
[0042] Stabilizer 24 is a substantially U-shaped spacer positioned
in the rear portion of cartridge 10 and between upper and lower
cartridge shell halves 18a and 18b. Rear cartridge shell tabs 318a
and 318b extend rearwardly from upper and lower shell halves 18a
and 18b and wrap around stabilizer 24. Therefore, when cartridge 10
is assembled, a portion of stabilizer 24 extends into and between
the shell halves 118a and 18b and portions of stabilizer 24
protrude from joined upper and lower shell halves 18a and 18b. The
protruding portions of stabilizer 24 form portions of the outer
contours of cartridge 10. In particular, stabilizer 24 forms
cartridge rear corners 24a and 24b and forms rear portion 24c.
[0043] Stabilizer 24 is formed of a lightweight rigid material such
as plastic. More preferably, stabilizer 24 is formed of high impact
polystyrene. It is formed from any one of the well-known plastic
forming processes, such as injection molding. Stabilizer 24
provides dimensional stability and rigidity to cartridge 10,
thereby minimizing cartridge deformation during mishandling,
twisting, and so on.
[0044] Shutter spring mechanism 22 comprises a guide wire 23 and a
round helical compression spring 21 that is slid over guidewire 23.
Shutter spring mechanism 22 is fixed to stabilizer 24 at the ends
of guide wire 23. The ends seat in channels 124a and 124b that are
formed into the ends of U-shaped stabilizer 24. The operational
details of shutter spring mechanism 24 are described in further
detail below in connection with the description of cartridge
opening and closing.
[0045] Flexible magnetic disk 14 is formed of a thin polymer film,
such as MYLAR, and has a thin magnetic layer uniformly dispersed on
the top and bottom surfaces thereof. The magnetic layer makes the
flexible disk 14 susceptible to magnetic flux and enables the
storage of digital data when the disk surface is brought into
magnetic communication with a magnetic transducer of the type
commonly found in disk drives. Disk 14 is generally circular with a
circular hole proximate the center of disk 14. Disk 14 has a radius
r in a range of about 20 to 25 mm, and preferably about 23.25 mm.
Disk 114 has concentric tracks 114 that provide the formatting of
disk 14 to store digital information. Disk 14 contains a high
density of tracks per inch (TPI), preferably in a range of about
2900 to about 3100 TPI, more preferably disk 14 contains about 3050
TPI. This high track density, which incidentally is much high that
the common 1.44 megabyte floppy TPI of about 10 TPI, allows the
relatively small disk 14 to store at least 40 megabytes of digital
data.
[0046] Media hub 12 is essentially donut shaped and comprises a
ferrous material such as steel, preferably stainless steel. The
surface finish is about 8 micro inches to reduce sliding function.
Hub 12 comprises a bore or hole 12a proximate the center,
peripheral outer edge 12b and inner ring surface 12c. Inner ring
12c has an outer angled edge and a substantially flat bottom
surface. Outer peripheral edge 12b is also angled. Media hub 12 is
firmly secured to disk 14 such that the center of hub 12 is aligned
proximate the center of disk 14. Media hub 12 is preferably
attached to disk 14 via a well-known adhesive process. The disk and
hub assembly are rotatably disposed between upper and lower
cartridge shutter shell halves 16a, 16b. Hub 12 is disposed in
spindle access hole 316b of spindle access opening 316c of lower
shutter shell 16b and spindle access hole 218b of lower cartridge
shell 18b. As described in further detail below, the protrusion of
hub 12 from shutter shell 16 and an cartridge shell 18 enhances
coupling to a rotational power source, such as that provided by a
drive spindle, when cartridge 10 is within drive 50 and acts a
restraint on lateral movement of disk 14 when the cartridge is
removed drive 50.
[0047] As shown by FIGS. 7 and 8, shutter halves 16a and 16b snap
together to form shutter shell 16, which houses media 14 and
shutter liners 15a and 15b (not shown in FIG. 5) which are attached
to the inner surfaces of shutter shells 16a and 16b respectively.
The complete shutter assembly 28 is pivotally attached to top shell
18. Hub 12 is attached to media 14 and protrudes through drive
access hole 316b in shutter shell 16b. Accordingly, when cartridge
10 is inserted and operating in drive 50, media 14 rotates within
shutter shell 16. As best appreciated from Figure unlike other disk
cartridges which do not rotate within the shutter but which rotate
within cartridge shell 18. Pivot post 20 attaches shutter assembly
28 to upper shell half 18a by attaching the top portion 20 to pivot
hole 218b via shutter pivot hole 316. Pivot post 20 is fixedly
attached to top shell cartridge 18a while leaving an offset space
between and around post portion 20a and shutter pivot hole
316a.
[0048] The use of an internal shutter shell provides several
advantages over other internal shutter designs. Among the
advantages are improved cartridge 10 rigidity, improved disk 14
aerodynamics, and improved shutter control. The improved rigidity
results from cartridge 10 having two layers of shell material
(shutter 16 and shell 18) to guard against mishandling. The
improved disk 14 aerodynamics result from the fact that space
within which disk 14 rotates is completely controlled and free of
disturbances caused by other internal mechanical features. For
example, in other internal shutter designs, the retracted shutter
only covers a portion of the spinning disk thereby increasing the
likelihood of air flow disturbances. The final example of the
benefits of shutter 16 of the present invention is improved shutter
opening control. Shutters typically have a biasing mechanism to
close the shutter. In the present shutter design, a spring 21
provides such a bias. Here, spring 21 can be located in the rear of
the cartridge 10 and still control the operation of shutter 16.
[0049] When shutter assembly 28 is complete, media 14 is exposed at
media access opening 416. However, and as described more fully
below, media 14 within cartridge 10 is only accessible from outside
of cartridge 10 when shutter access opening 416 aligns with
cartridge shell access opening 418. In such an alignment, shutter
shell 16 moves to a first position so that the openings 416, 418
completely overlap thereby "opening" cartridge 10. When the
cartridge shell access opening 416 and cartridge shell access
opening 418 are misaligned, shutter shell 16 moves to a second
position such that the openings 416, 418 do not over lap thereby
"closing" cartridge 10, shielding media 14 from ambient
contaminants.
[0050] FIGS. 9 and 10 illustrate the "opening" and "closing"
operation of shutter shell 16 with spring mechanism 22. FIG. 6 is a
top plan view of cartridge 10 in the closed position with upper
cartridge shell 18a removed for clarity. FIG. 7 is a top plan view
of cartridge 10 in the open also with upper cartridge shell 18a
removed for clarity. The motive force for biasing shutter 16 toward
the closed position is provided by compression spring 23 in an
arcuate path. As noted above, compression spring 21 is slid over
arcuate guidewire 23, which is attached to the ends of U-shaped
stabilizer 24 in slots 124a and 124b. After attachment of
compression spring 23 onto guidewire 21, spring 23 follows the
arcuate path established by guidewire 21. Other structures are
possible for forming an arcuate spring path. For example, an
arcuate channel cut into the stabilizer 24 would also provide an
arcuate path for spring 23. However, the use of guidewire 23 is
preferred because it facilitates construction of cartridge 10 by
improving the handling of spring 21. That is, spring 21 easily
conform to the shape of wire 23 which is then attached to
stabilizer 24.
[0051] Shutter shell 16 has an extending tab 17 that couples an
translates a force between shutter 16 and spring 21. Tab 17 is
preferably formed into shutter 16 but could alternately be attached
to shutter shell 16 as a separate part such as by welding. Tab 17
extends outwardly from shutter shell 16 so as to extend into the
spring path, overlapping guide wire 23. When cartridge 10 is in the
closed position, compression spring 21 engages tab 17 biasing
shutter 16 toward the closed position. To open cartridge 10, a
counterclockwise rotational force is applied to shutter shell 16
(from the perspective of FIGS. 6 and 7) against the bias of spring
21, thereby compressing spring 21. When the rotational force is
removed from shutter shell 16, spring 21 biases shutter shell 16
back to the closed position.
[0052] Cartridge 10 has several features (best described with
respect to FIGS. 9 and 10) that cooperate in the operation of
shutter 16 in conjunction with drive 50. These features include,
catch feature 516, flat nose portion 518, and retraction slot 618
(see FIG. 5 for an alternate view of retraction slot 618).
[0053] Shutter catch feature 516 protrudes outwardly from the
radius of shell 16. Catch feature 516 provides two significant
functions in the operation of shutter 16: first, it provides a stop
when spring 21 biases shutter 16 toward the closed position; and
second, it provides a mechanism for coupling with drive 50 so that
shutter 16 can be opened during insertion into drive 50. The stop
function of catch 16 operates when shutter 16 rotates toward the
clockwise direction. When rotated to the closed position, catch 516
engages the cartridge shell edge and thereby stops the rotation of
shell 16.
[0054] Referring to FIGS. 11A-11E, the operation of shutter shell
16 with drive 50 is further illustrated. Referring to FIG. 11A,
cartridge shell 18 also has a flat nose portion 518 which is
adjacent to catch feature 516 when shutter shell 16 is in the
closed position. Upper cartridge shell 18a has an overhang 718,
proximate flat nose portion 518, that shields catch 516 when the
cartridge is not in drive 50. Shutter 16 is opened by shutter lever
48. Shutter lever 48 has a hook like portion 48a on its proximal
end. Hook like portion 48a has an upstanding tab portion 148 that
is adapted to engage shutter shell 16. When a cartridge 10 is
inserted into drive 50, upstanding tab 148 engages flat nose
portion 518. The relatively flat and wide upstanding tab 148 and
flat nose portion 518 provide sufficient area to ensure that lever
48 properly and reliably engages shutter 16. Additionally, flat
nose portion 518 enhances the pressure angle to more easily begin
the rotation of shutter 16. When properly engaged, an edge of
upstanding tab 516 mates with catch 516.
[0055] A retraction slot 618 is cut into the lower cartridge shell
18b. Retraction slot 618 permits the upstanding tab to retract,
along with catch 516, into cartridge shell 18 and move out of the
way of the other drive 50 components. This ability to retract the
shutter opening mechanism and catch 516 results in a larger disk
access opening. FIG. 11E illustrates cartridge 10 loaded fully into
drive 50 with lever 48 and shutter shell 16 fully retracted.
[0056] Shutter lever 48 is pivotally mounted at its distal end 48b
to drive chassis 57 proximate the front portion of drive 50.
Shutter lever 48 is biased by a spring (not shown) in a clockwise
direction (as viewed in FIGS. 11B-11E). As a result of the bias,
lever 48 pivots to a positioned proximately as shown in FIG. 11B
when a cartridge 10 is absent from drive 11.
[0057] As best illustrated in FIG. 11C, when cartridge 10 is
inserted into drive 50, the nose 518 of cartridge 10 engages
shutter lever 48. At the point of engagement, hook end 48 of
shutter lever 48 mates with catch 516. After the shutter lever 48
has engaged shutter catch 416, the force of insertion (supplied by
the user) of cartridge 10 further into drive 50 will cause shutter
16 to rotate in tandem with lever 48 in the counterclockwise
direction. The rotation of lever 48 against the clockwise spring
bias loads the spring of lever 48. Similarly, the rotation of
shutter 16 against the bias of spring 21 loads shutter spring 21.
Accordingly, when cartridge 10 ejects from drive 50, spring 21
causes shutter 16 to snap shut and lever 48 to return to a position
proximate the position shown in FIG. 11B. FIG. 11D shows the first
stages of shutter 16 rotation as cartridge 10 moves further into
drive 50. FIG. 11E shows the complete insertion of cartridge
10.
[0058] Shutter 16 and lever 48 disengage in essentially the reverse
sequence from that described above in connection with FIGS.
11A-11E. However, the ejection of cartridge 10 from drive 11 is
aided by spring 21 of cartridge 11. In particular, as cartridge 10
ejects from drive 50, the force of spring 21 rotates shutter 16 in
the clockwise direction. The force of spring 21 causes catch 516 to
impinge upon upstanding tab 148. This force also causes cartridge
10 to move outwardly from drive 10. Of course, this force to move
the cartridge outwardly diminishes as the shutter lever moves
clockwise toward its pre-loaded position. Further details of a disk
drive insertion and ejection mechanism are described in co-pending
patent application Ser. No. ______ (Attorney Docket No. IOM-9720)
entitled "METHOD AND APPARATUS FOR CARTRIDGE EJECTION AND OVERWRITE
PROTECTION" filed Nov. 13, 1997, which is hereby incorporated by
reference in its entirety.
[0059] FIG. 12 shows an isometric view of the underside of
cartridge 10. Hub 12 is disposed in spindle access hole 18d of
cartridge 10. Hub 12 comprises a substantially flat bottom surface
12e, and an inner ring 12c, and an outer peripheral edge 12b. Also
shown in FIG. 12, bottom shell half 18b has a rounded edge 218c
around drive access hole 218b. Hub 12 and rounded edge 218c
interact to restrain lateral movement of disk 14 within cartridge
shell 18.
[0060] Unconstrained lateral movement of disk 14 within cartridge
10 could cause the edges of disk 14 to impinge upon the inner
circumference of shutter 16. Such impingement could damage disk 14
causing data loss or worse. Referring also to FIG. 13 (a cross
section of FIG. 12 along the line 13-13), hub 12 and attached disk
14 are free to move laterally (in the x and y plane) within
cartridge 10 by the distance indicated by line 112. However, hub 12
projects outwardly from drive access hole 218b (see also FIG. 6).
This projection of hub 12 is much more pronounced than with
conventional floppy disk cartridges. The projection is so
pronounced that even if hub 12 is pushed up ( in the z direction)
into cartridge 10, hub 12 still projects out from drive access hole
218b. The overall effect of the hub projection is to prevent disk
14 from moving laterally so that its edges contact the inner
circumference of shutter 16.
[0061] During insertion of cartridge 10 into drive 50, spindle 40
remains fixed and cartridge 10 slides in a fixed plane relative to
spindle 40. In other words, unlike typical cartridge insertion
mechanisms used in other disk drive systems, in present drive 50
and cartridge 10 there is no translation of either cartridge 10 or
spindle 40 in the z-axis. Accordingly, to mount hub 12 to spindle
40, hub 12 undergoes z-axis translation as it slides along the top
surface of spindle motor 53 and over spindle 40. This z-axis
translation of hub 12 is best illustrated with reference to FIGS.
14A-14C, which present cut-away side views of cartridge 10 and
drive 50 that loosely correspond in relative position to cartridge
10 and drive 50 in FIGS. 11, along lines 14-14.
[0062] Peripheral edge 12b preferably forms angled outer surface
that is adapted to engage with a rounded edge of the spindle access
opening during upward translation into shell 18. The preferred
angle .alpha. for the outer edge is about 45 degrees. More
preferably peripheral outer edge 12b substantially forms a ring
around the circumference of hub 12. However, other configurations
could accomplish a similar function, such as spoke-like or fingers
of angled surfaces rather than a solid annular surface depicted in
the figure. Similarly, inner ring surface 12c, preferably
substantially ring shaped, could also comprises a different form,
for example a series of fingers. Inner ring surface 12c also has a
preferred angle, .beta., of about 45 degrees.
[0063] As shown by the cut-away side views, hub 12 has a stepped
side profile. Disk 14 is attached to the hub along a topmost
surface 12h of hub 12. A step down from top surface 12h is a
surface 12j, which forms the top of peripheral outer edge 12b. The
step provides a gap 13 between the hub 12 and disk 14. As is
described more fully below, gap 13 provides additional flexibility
for vertical translation of hub 12 within cartridge 10.
[0064] Spindle motor 40 has several features that are adapted to
interact with hub 12. In particular, spindle 40 includes the "z"
datum 40a (provided by a raised ring), a round boss surface 40b and
a conical lead-in groove 40c. All of these features cooperate to
enable engagement and disengagement of hub 12 from spindle 40. In
addition, the top of spindle 40 is magnetically sensitized to
attract and magnetically couple hub 12 to spindle 40.
[0065] Significantly, hub 12 engagement and disengagement from
spindle 40 occurs without translating the plane of cartridge 10
vertically (i.e. in the z-axis direction) relative to the plane of
the drive or without translating the spindle motor. Consequently,
the height of drive 10 can be thinner than is possible in either a
spindle or cartridge translation method. Instead of translating
either the spindle or the cartridge, hub 12 and media 14 are
translated along the z-axis within shell 18 as the cartridge is
translated linearly (i.e., along a plane substantially parallel to
the x-axis) into and out of drive 50. No additional space is
required within cartridge shell 18 to accommodate the z-axis
translation of hub 12, other than space which is already available
to allow disk 14 to spin freely within shell 18. The present
invention can even function properly with less interior cartridge
space than that provided in a common 3.5 inch disk cartridge.
[0066] During insertion of cartridge 10 into drive 50, as depicted
in FIG. 4A, hub 12 slides on inner ring surface 12c over the
relatively planar profile of the bottom of chassis 57 and over the
top of spindle 40. The ring surface provided by inner ring 12c
provides a relatively large surface area for hub 12 to slide upon
during insertion into drive 50. This large surface area ensures
that the hub slides smoothly into drive 50. Downwardly projecting
pin 20 is coupled proximate the center of cartridge 10 to top shell
portion 18a. The downwardly projecting pin 20, engages sidewall 12a
of hub 20 urging it into chassis 57.
[0067] A force applied to cartridge 10 during insertion causes pin
20 to push against the sidewall of bore 12a. This pushing provides
a force to overcome the friction between inner ring surface 12c and
chassis 57 and top of spindle 40. As cartridge 10 reaches far
enough into drive 50, inner ring surface 12c aligns with conical
lead-in groove 40c. At that point, the magnetic force provided by
spindle 40 attracts and pulls hub 12 into engagement with spindle
40, resulting in inner ring surface 12c extending into conical
lead-in groove 40c. As best shown in FIG. 4B, the angles of lead-in
groove 40c and inner ring surface 12c, preferably proximately 45
degrees, are such that hub 12 properly aligns on center with
spindle 40 as hub 12 is pulled into a seated position. In
particular, inner ring 12c forms a cone-like male surface that
corresponds with the cone-like female opening of lead-in groove
40c. As the two cone-like surfaces engage, inner ring 12c is guided
by conical lead-in groove 40c. Moreover, the relatively large
diameter of inner ring surface 12c (as measured across hub 12) and
conical lead-in groove 40c ensures a highly accurate alignment of
hub 12 to spindle 40.
[0068] As cartridge 10 ejects from drive 50, hub 12 disengages from
spindle 40, again, without vertical translation of cartridge 10
with respect to drive 50 (only hub 12 and media 14 translate in the
z-axis). As best shown in FIG. 4C, when cartridge 10 starts
ejection from drive 50, cartridge shell 18 moves outwardly from
drive 50. During this outward movement of cartridge shell 18, hub
12 initially remains seated on spindle 40. A force is required to
cause disengagement of hub 12. The required force is provided by
the movement of cartridge shell 18 relative to hub 12. Cartridge
shell 18 has downwardly projecting pin 20 and rounded edge 18c that
cooperate with hub 12 to facilitate disengagement.
[0069] Disengagement begins when pin 20 impinges on the sidewall of
bore 12a. Substantially simultaneously, rounded edge portion 18c
contacts the angled peripheral outer edge 12b. As shell 18
continues to move outwardly, rounded edge 18c slides against angled
peripheral edge 12b. The horizontal movement (along the x-axis) of
rounded edge 18c relative to angled edge peripheral edge 12b urges
a lifting hub 12. The combined impingement of pin 20 and lifting of
shell 18b cause hub 12 to tilt about datum 40a. As hub 12 tilts,
inner ring surface 12c also tilts. When the bottom surface 12f of
inner ring 12c clears the top 40d of spindle 40 hub 12 can also
move begin moving outwardly with cartridge 10. As hub 12 moves
outwardly, angled inner ring surface 12g engages angled spindle
lead-in groove surface 40c. Because both surface are angled, hub 12
slides up the side of lead-in groove surface 40c.
[0070] As best shown in FIG. 14D, when bottom surface 12f of inner
ring 12c clear datum 40a of spindle 40, hub 12 is free to move with
cartridge 10. Thereafter, pin 20 urges hub 12 to travel in tandem
with cartridge shell 18. The force of pin 20 continues to drag hub
12 over the surface of spindle motor 53 and chassis 57 until
cartridge 10 has ejected from drive 50.
[0071] The stepped profile of hub 12 allows for additional headroom
as hub 12 tilts within cartridge 10. That is, without a stepped
hub, the tilting could cause the top of hub 12 to impinge upon the
inner top surface of shell 18a and interfere with the disengagement
of hub 12 from spindle 40. Moreover, the stepped hub allows the
disk 14 to flex as hub 12 is tilted during disengagement.
[0072] A best illustrated in 14A, hub 12 is translated in the
z-axis direction during cartridge 10 insertion into drive 50. As a
result, disk 14 is push upward to the inner surface of upper
shutter shell 16a an against liner 15a (not shown in this Figure
for clarity). This upward translation of hub 12 allows it to clear
the top of spindle 40. However, as a side effect of the upward
location of disk 14, the edge of disk 14 must be adjusted
downwardly to thread the head loading ramps 47 as described more
fully below.
[0073] FIG. 15A shows an isometric view of the load ramp in
accordance with the present invention. Load ramp 47 comprises a
base 67, head guard 61, pivoting arms 60a and 60b, abutments 66a
and 66b, pivot pin 65, and compression spring 69. Each arms 60
comprises a ramped end portion 64 and a tail portion 63. Pivoting
arms 60a and 60b are arranged to pivot about pivot pin 65 in
opposing fashion between an open position, in which the ramped ends
pivot away from each other, and a closed position in which the
ramped ends pivot toward each other. Spring 69 is disposed between
the arms 60a and 60b such that the arms 60a and 60b are biased
toward the closed position. Tail portions 63a and 63b of arms 60a
and 60b, respectively, engage the corresponding abutments 66a and
66b to restrain the rotational travel of arms 60a and 60b when they
are biased toward the closed position. Base 67 also comprises a
hole 70 for attachment to the drive chassis 57 by means of a screw
or other common attachment means. Head guard 61 extends out from
the base 67 and provides opposing surfaces 61a and 61b. Each
surface 61a and 61b has a ramped front portion 62a and 62b,
respectively. Each of these surfaces 61a and 61b provides a surface
for heads 46 to rest when the actuator 49 is in the parked
position.
[0074] Referring now to FIGS. 15B and 15C, side views of load ramp
47 are shown. In FIG. 15B, pivot arms 60a and 60b are in the open
position, with spring 69 compressed (by load beams 44, which are
not shown for clarity). Accordingly, the distance between ramped
end portions 64a and 64b is maximized. With the distance thus
maximized, media 14 entering between the end portions 64a and 64b
has sufficient space to fluctuate during loading without a
collision between media 14 and load ramp 47. In FIG. 15C, the pivot
arms 60a and 60b are in the closed position. Once the media is
fully inserted into drive 50, pivoting arms 60a and 60b can safely
close over media 14 without damage to media 14. With arms 60a and
60b in the closed position, heads 46 can safely move between media
14 and load ramps 47.
[0075] Because hub 12 and disk 14 are translated upwardly from hub
12 sliding over chassis 57. When hub 12 is compressed into liner
15a, disk 14 is forced out of plane. Forcing disk 14 out of plane
in this way causes a large distortion at outer peripheral edges of
disk 14. The edge distortion, in turn, could cause disk 14 to
travel over the top of load ramp end portions 64 rather than
properly threading between end portions 64a, 64b. An adjustment to
the disk 14 at the disk access opening is necessary to ensure that
disk 14 properly threads between load ramps end portions 64a and
64b.
[0076] Accordingly, referring now to FIG. 16, a isometric bottom
view of upper shutter shell half 16a with attached liner 15a is
shown. Liner 15a is attached to the inner surface 216a of shutter
half 16a. Liner 15a is cut around post hole 316a exposing a portion
of inner surface 216a (about the size of drive access hole 316b).
Distortion neutralizer 11 is disposed on surface 216a of shutter
half 216a proximate the apex of wedge-shaped disk access opening
416a. (See also FIG. 7). Media distortion neutralizer 11 comprises
a raised surface on inner surface 216a. The raised surface can be
formed by attaching material to surface 216a. The thickness of the
distortion neutralizer is at least one thickness of liner 15a and
no thicker than about half the thickness of the space between
shutter shell halves 16. Most preferably, it is about 0.2 mm thick.
The width of distortion neutralizer 11 is limited by the relatively
small size of the present cartridge 10. That said, it is further
limited by the distance between the edge of disk access opening
416a and hub 12. Accordingly, the width is between about 1 and 2
mm, preferably about 1.5 mm. Preferably, the raised surface is
formed by stamping the distortion neutralizer directly into upper
shell half 216a. Moreover, shell liner 15a is preferably attached
over the top of the raised surface to protect disk 14 from direct
metal contact on media distortion neutralizer 11. Media distortion
neutralizer 11 is preferably arced, more preferably the arc is a
portion of a circle so as to be concentric with disk 14; however,
it could also be substantially straight. Thus, when cartridge 10 is
assembled, media distortion neutralizer provides a ridge of
material projecting downwardly from an upper surface of cartridge
10. This projecting surface ensures that disk 14 is forced
downwardly toward the a plane proximately more centered between
upper and lower cartridge halves 18a, 18b. The more centered disk
14, therefore, more reliably threads between head load ramp ends 64
during cartridge insertion into drive 50.
[0077] The above description of preferred embodiments is not
intended to impliedly limit the scope of protection of the
following claims. Thus, for example, except where they are
expressly so limited, the following claims are not limited to
applications involving cartridges for disk drive systems.
* * * * *