U.S. patent application number 09/901935 was filed with the patent office on 2002-02-21 for mechanism to clamp magnetic disk against cartridge shell.
This patent application is currently assigned to Iomega Corporation. Invention is credited to Blum, James, Bracken, Allen T., Krieger, George.
Application Number | 20020021530 09/901935 |
Document ID | / |
Family ID | 22379828 |
Filed Date | 2002-02-21 |
United States Patent
Application |
20020021530 |
Kind Code |
A1 |
Bracken, Allen T. ; et
al. |
February 21, 2002 |
Mechanism to clamp magnetic disk against cartridge shell
Abstract
A data storage cartridge has a recording medium and a door
covering an opening in the shell. The door is opened when the
cartridge is inserted into the drive and closed when the cartridge
is removed from the drive. A movable member rotates in cooperation
with a stationary member by a actuating arm that is coupled to the
door. Preferably, a screw/nut mechanism is operated by the opening
and closing of the door to actuate a clamping mechanism which
clamps the recording against a planar wall of the shell when the
cartridge the is removed the drive
Inventors: |
Bracken, Allen T.; (Layton,
UT) ; Blum, James; (San Jose, CA) ; Krieger,
George; (Carmel, CA) |
Correspondence
Address: |
Woodcock Washburn Kurtz
Mackiewicz & Norris LLP
One Liberty Place - 46th Floor
Philadelphia
PA
19103
US
|
Assignee: |
Iomega Corporation
|
Family ID: |
22379828 |
Appl. No.: |
09/901935 |
Filed: |
July 10, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09901935 |
Jul 10, 2001 |
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09118635 |
Jul 17, 1998 |
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6304417 |
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09118635 |
Jul 17, 1998 |
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08834188 |
Apr 15, 1997 |
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5862026 |
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08834188 |
Apr 15, 1997 |
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08550818 |
Oct 31, 1995 |
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5650899 |
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08550818 |
Oct 31, 1995 |
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08477764 |
Jun 7, 1995 |
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Current U.S.
Class: |
360/133 ;
G9B/23.031; G9B/23.033; G9B/23.036; G9B/23.044 |
Current CPC
Class: |
G11B 23/0312 20130101;
G11B 23/0323 20130101; G11B 23/0308 20130101; G11B 23/0306
20130101 |
Class at
Publication: |
360/133 |
International
Class: |
G11B 023/03 |
Claims
What is claimed:
1. A cartridge for a drive in which read/write heads read/record
data on a recording medium comprising: a shell having a front, a
back and two sides between substantially flat, planar surfaces;
said recording medium being in said shell; said shell having an
opening in the front thereof for access by said read/write to said
recording medium; a door covering said opening when said cartridge
is removed from said drive; a screw having screw threads; a nut
having threads engaging said threads; one of said screw and said
nut being connected to said shell and the other being connected to
said door so that movement of said door between positions covering
said opening and not covering said opening causes relative movement
between said screw and said nut; and clamping means movable by said
relative movement to clamp said medium against a planar surface of
said shell when said door is closed.
2. The cartridge recited in claim 1 wherein said screw is rotatable
on the same axis as said recording medium and said nut is connected
to said shell.
3. The cartridge recited in claim 1 wherein said nut is rotatable
on the same axis as said recording medium and said screw is
connected to said shell.
4. The cartridge recited in either one of claims 1 and 2 wherein
said clamping means is moved axially by said relative movement.
5. The cartridge recited in either one of claims 1 and 2 further
comprising: a hub on which said recording medium is mounted, said
clamping means applying an axial force to said hub to clamp said
medium against a planar wall of said shell.
6. The cartridge recited in claim 5 further comprising a coil
spring disposed on said axis, said spring biasing said clamping
means against said hub to clamp said medium against said planar
wall when said door is closed.
7. The cartridge recited in claim 6 wherein said coil spring is
compressed pulling said claiming means away from said hub as said
door is opened.
8. The cartridge recited in claim 7 wherein said screw is attached
to a planar surface of said nut is rotatable about said screw by
said door.
9. The cartridge recited in claim 8 wherein said nut is attached to
a planar shell and said screw is rotatable about said nut.
10. The cartridge recited in claim 8 wherein said screw is molded
into a planar wall of said shell.
11. The cartridge recited in claim 1 wherein said one of said screw
and said nut is connected to said door by a member rotatable about
the axis of said recording medium.
12. The cartridge recited in claim 11 wherein said spring returns
said door to the closed position when said cartridge is removed
from said drive.
13. A cartridge for a drive in which read/write heads read/record
data on a recording medium, comprising: a shell having a front, a
back and two sides between substantially flat, planar surfaces;
said recording medium being in said shell; said shell having an
opening in the front thereof for access by said read/write to said
recording medium; a door substantially covering said opening when
said cartridge is removed from the drive; an actuating arm having a
first end and an opposing second end that is coupled to the door; a
stationary member rigidly coupled to one of the planar surfaces;
and a movable member coupled to the actuating arm and movably
coupled to the stationary member such that movement of the door
produces axial translation of the movable member, whereby said
axial translation enables clamping of said medium against a planar
surface of said shell when said door is closed.
14. The cartridge of claim 13 wherein said movable member is
coupled to said stationary member such that movement of said door
produces rotation of said movable member relative to said
stationary surface, said movable member coupled to said stationary
member such that rotation of the movable member produces axial
translation of the movable member.
15. The cartridge of claim 14 wherein said translating member has a
sliding surface slidably coupled to a stationary surface disposed
on said stationary member, at least one of said sliding surface and
said stationary service defining an incline for axially translating
the translating surface upon rotation of said movable member.
16. The cartridge of claim 14 wherein the stationary member has a
surface that extends which extends axially as a function of the
circumference of said stationary member when the translating member
is rotated as said door is opened and closed.
17. The cartridge of claim 13 further comprising a spring having
one end coupled to said stationary member and an other end coupled
to said movable member, said spring biasing said movable member
toward an unclamped position.
18. The cartridge of claim 17 wherein the spring is disposed around
an axis of rotation of the recording medium.
19. The cartridge of claim 17 wherein the spring is disposed
proximate the periphery of said movable member.
20. The cartridge of claim 13 wherein the stationary member
comprises a screw rigidly coupled to one of the planar surfaces and
the movable member comprises a nut movably coupled to said
screw.
21. The cartridge of claim 20 wherein the screw has screw threads
disposed thereon, and the nut has nut threads disposed thereon that
are capable of meshing with said screw threads.
22. The cartridge of claim 21 further comprising a spring having
one end coupled to said screw and an other end coupled to said nut,
said spring biasing said nut toward an unclamped position.
23. The cartridge of claim 22 wherein the spring is disposed around
an axis of rotation of the recording medium.
24. The cartridge of claim 13 wherein the stationary member
comprises a nut rigidly coupled to one of the planar surfaces and
the movable member comprises a screw movably coupled to said
nut.
25. The cartridge of claim 24 wherein the screw has screw threads
disposed thereon, and the nut has nut threads disposed thereon that
are capable of meshing with said screw threads.
26. The cartridge of claim 25 wherein said nut has a cut away
portion to provide access to said screw by said recording arm.
27. The cartridge of claim 25 further comprising a spring having
one end coupled to said screw and an other end coupled to said nut,
said spring biasing said screw toward an unclamped position.
28. The cartridge of claim 27 wherein the spring is disposed around
an axis of rotation of the recording medium.
29. The cartridge of claim 13 wherein the stationary member
comprises screw threads coupled to one of the planar surfaces, and
the movable member comprises a nut having nut threads that are
capable of meshing with said screw threads.
30. The cartridge of claim 29 wherein the screw threads are formed
on a rim of the one planar surface proximate a spindle motor
aperture.
31. The cartridge of claim 30 further comprising a spring having
one end coupled to said nut and an other end coupled to said one
planar surface, said spring biasing said nut toward an unclamped
position.
32. The cartridge of claim 13 wherein the screw comprises a
protrusion, and the nut comprises a groove capable of cooperating
with said protrusion to axially translate the nut in response to
rotation of the nut.
33. The cartridge of claim 13 wherein the groove is inclined
relative to at least one of planar surfaces.
34. The cartridge of claim 13 wherein the movable member comprises
a coil and a plate coupled to said coil, said plate capable of
axial translation in response to rotation of said coil.
35. The cartridge of claim 34 wherein the coil comprises a first
end coupled to said actuating arm and a second end coupled to said
plate.
36. The cartridge of claim 34 wherein said stationary member
comprises a post that is rigidly coupled to said shell and that
defines a longitudinal keyway therein, and wherein said plate
comprises a disk having a center cutout and a key projecting into
said center cutout, said key capable of insertion into said keyway
so as to prevent said plate from rotating
37. A cartridge for a drive in which read/write heads read/record
data on a recording medium, comprising: a shell having a front, a
back and two sides between substantially flat, planar surfaces;
said recording medium, being in said shell, having a disk hub that
forms a cavity therein; said shell having an opening in the front
thereof for access by said read/write to said recording medium; a
door substantially covering said opening when said cartridge is
removed from the drive; an actuating arm having a first end and an
opposing second end that is coupled to the door; a clamping
mechanism, at least partially insertable within said cavity.
Description
[0001] Cross Reference to Related Applications: this application is
a continuation-in-part of co-pending U.S. application Ser. No.
08/834,188, filed Apr. 15, 1997, which is incorporated herein by
reference in its entirely, and which is a continuation of U.S.
application Ser. No. 08/550,818, (which issued as U.S. Pat. No.
5,560,899) filed Oct. 31, 1995, which is a continuation-in-part of
U.S. patent application Ser. No. 477,764, filed Jul. 7, 1995, which
is now abandoned.
FIELD OF THE INVENTION
[0002] This invention relates to data storage drives and more
particularly, to a removable cartridge for magnetic disk
drives.
BACKGROUND
[0003] Magnetic disk drives which write and read digital data from
flexible magnetic disks have been extensively used. "Floppy disk
drives" have been extensively used for small, so-called
microcomputer systems, for word-processing applications and the
like. The flexible disk cartridge includes a relatively thin,
flexible jacket which is inserted into the floppy disk drive.
[0004] Rigid disk drives, such as the IBM 3350, usually have a
fixed rigid magnetic media. The magnetic heads do not contact the
magnetic surface, but ride on a thin film of air. Because of this,
and other features, these disk drives are capable of extremely
precise and high speed operation. This type of disk drive is
commonly referred to as a "Winchester" drive. Rigid disks enclosed
in a rigid, removable cartridge, or shell have also been used. U.S.
Pat. No. 4,864,452-Thompson et al is an example of such a
drive.
[0005] "Bernoulli" disk drives having performance characteristics
similar to that of Winchester drives, but with removable
cartridges, have been developed. A flexible magnetic disk is
enclosed in a rigid box which is normally completely closed. U.S.
Pat. No. 4,400,748-Bauck, et al and related patents to the common
assignee show such drives using Bernoulli stabilized flexible
disks. U.S. Pat. No. 4,901,173-Jones et al and related patents to
the common assignee, show improvements which relate to so-called
"half height" drives.
[0006] The cartridges for these drives have a door which closes the
cartridge when it is removed from the drive. This prevents debris
from contaminating the magnetic recording medium when the cartridge
is not in the drive. When the cartridge is inserted into the drive,
this door slides to an open position to provide access for the
magnetic recording heads to engage the recording medium.
[0007] When the cartridge is removed from the drive, it is often
subject to rough handling. During handling, physical contact of the
disk with the shell may damage the disk, particularly if the disk
and cartridge shell are subject to excessive "rattling".
[0008] U.S. Pat. No. 5,444,586, Iftikar, et al. discloses a
mechanism for clamping the cartridge against the cartridge shell
when the cartridge is removed from the drive and releasing the
clamping mechanism when the cartridge is inserted into the drive.
In the Iftikar, et al. patent a nut and screw mechanism is actuated
by a tang which is rotated as the cartridge is inserted into the
drive. Unfortunately, such a design requires added complexity of
the drive because the mechanism to actuate the tang is disposed
within the drive, as distinguished from within the cartridge.
[0009] U.S. Pat. No. 5,650,899 Schick, et al. discloses a cam
mechanism which clamps the hub against the cartridge shell as the
access door of the cartridge is opened and closed when the
cartridge is inserted into or ejected from the drive.
[0010] It is a goal of the present invention to provide an
advantageous clamping mechanism which is actuated by the opening
and closing of the cartridge door as it is inserted into and
ejected from the drive, which optimizes head space, which reduces
the number of moving parts, and which diminishes rattling of the
cartridge while the cartridge is outside of the drive.
SUMMARY OF THE INVENTION
[0011] In accordance with the present invention, a clamping
mechanism in a data storage cartridge includes a movable member and
a stationary member. The mechanism is actuated by the door of the
cartridge which is opened when the cartridge is inserted into the
drive and is closed when the cartridge is removed from the drive.
The mechanism of the present invention restrains the recording
medium to prevent rattling when the cartridge is removed from the
drive, i.e. when the door closed. The clamping mechanism is
disposed on the same axis as the rotatable recording medium.
[0012] When the door is closed the clamping mechanism translates
the motion of the door closing into a surface that clamps the hub
on which the recording medium is mounted against a the rear wall of
the cartridge. Preferably, the clamping mechanism is at least
partially located in a cavity formed in the hub while the clamping
mechanism is in the clamped position. The clamping mechanism
comprises a stationary member and a movable member. The stationary
member is affixed to the planar surface of the cartridge. The
movable is operationally coupled to the door via an actuating arm,
and movably coupled to the stationary member such that as the door
opens and closes, the movable member is rotated on the stationary
member. The door movement, thus, causes axially motion of the
clamping mechanism which is disposed in a cavity in the hub. A
surface of the clamping mechanism bears against the disk hub to
clamp the disk hub against the planar wall of the cartridge.
[0013] Four embodiments of the present invention are provided, each
of which provides an actuating arm that is coupled to the cartridge
door, a stationary member that is rigidly connected to the
cartridge shell, and a movable member that is coupled to the
stationary member. The actuating arm rotates the movable member,
which is coupled to the stationary member such that rotation of the
movable member produces axial translation of the movable member.
The movable member translates toward the recording medium housed
within the cartridge while the cartridge is removed from the drive
so as to clamp the recording medium between a contact surface of
the movable member and the cartridge shell.
[0014] In the first two embodiments, a spring that is coiled around
the axis of rotation provides torsion to the movable member, which
are a nut and a screw, respectively, to bias the movable member
toward the camped position. In the third embodiment, a helical
spring is disposed near the periphery of the movable member, which
is a screw, to bias the movable member toward the clamped position.
The fourth embodiment lacks a spring to bias the movable member,
which is a spiral spring and plate assembly. Therefore, the
clamping mechanism of the fourth embodiment may either be actuated
entirely by the door, or may be biased by a spring coupled to the
actuating arm.
[0015] The present invention produces the advantage that the
mechanism for actuating the clamping mechanism is disposed within
the cartridge shell, preferably within a cavity in the disk hub,
which saves vertical space within the drive and reduces complexity.
Further, providing a clamping mechanism that has only one moving
part (in addition to the door and the actuating arm) within the
cartridge produces less debris, which is an important and growing
consideration with increasing areal density of the magnetic
information.
[0016] The present invention encompasses any clamping mechanism
that is operatively coupled to the cartridge door and that includes
a movable member that is coupled to a stationary member such that
rotation or pivoting of the movable member results in axial
translation. For example, the present invention encompasses a
screw/nut combination regardless of whether the movable member
clamps the recording medium against the top or the bottom of the
cartridge shell, or whether the screw or the nut comprises the
movable member Further, in addition to a nut and screw arrangement,
the present invention encompasses a protrusion (for example, a pin)
that slides within a helical or inclined groove, and also a helix
or helically oriented members that slide within a helical
groove--regardless of whether the grooves are disposed in the
stationary or movable member. Further, the terms "screw" and "nut"
are broadly used herein to comprise threads of any type on either
or both the movable member and stationary member.
[0017] The foregoing and other objects, features and advantages of
the invention will be better understood from the following more
detailed description and appended claims.
SHORT DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1A shows a top view of the cartridge of the present
invention;
[0019] FIG. 1B is a front view of the cartridge;
[0020] FIGS. 3A and 3B are cross sectional views illustrating a
first embodiment of the present invention in an unclamped and
clamped position, respectively;
[0021] FIG. 4 is a view of a portion of the embodiment shown in
FIGS. 3A and 3B;
[0022] FIG. 5 is a portion of the embodiment shown in FIGS. 3A and
3B;
[0023] FIGS. 6A and 6B are cross sectional views illustrating a
second embodiment of the present invention in an unclamped and
clamped position, respectively;
[0024] FIG. 7 is a portion of the embodiment shown in FIGS. 6A and
6B;
[0025] FIGS. 8A and 8B are cross sectional views illustrating a
third embodiment of the present invention in an unclamped and
clamped position, respectively;
[0026] FIG. 9 is a view of a portion of the embodiment shown in
FIGS. 8A and 8B;
[0027] FIG. 10A and 10B are cross sectional views illustrating a
fourth embodiment of the present invention in an unclamped and
clamped position, respectively;
[0028] FIG. 11 is a view of a portion of the embodiment shown in
FIGS. 9A and 9B;
[0029] FIG. 12 shows a view of an actuating arm.
[0030] FIG. 13 is a view of an aspect of the present invention that
may be employed with any of the first three embodiments;
[0031] FIGS. 14 and 15 are perspective views of portions of the
mechanism shown in FIG. 13.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0032] FIGS. 1a and 1B show a cartridge having two half shells 11
and 122 joined together at 13. The cartridges has a front 14, a
back 15, and two sides 16 and 17. Between the two sides are two
substantially flat, planar surfaces: shell first planar surface 18
and shell second planar surface 19, which have four edges that
connect to the front 14, back 15, and sides 16 and 17. An opening
20 in the front of the cartridge provides access by the read/write
heads to the recording medium disposed within the cartridge. A
flexible door 23 covers the opening 20 when the cartridge is
removed or is outside of the drive. Door 23 sides in tracks 28
disposed in the planar surfaces 18 and 19. A spindle motor aperture
21, best shown in FIG. 3A, is disposed in surface 19.
[0033] When a cartridge, such as the cartridge of FIGS. 1A and 1B
is not in use (e.g., outside of a disk drive), it is desirable to
fix the recording medium into place such that it cannot "rattle"
inside of the cartridge shell. The following discussion uses
reference numerals with corresponding letters to refer generally to
parts of the invention. Description of particular embodiments below
use these reference numerals consistently, and add a letter
designation to distinguish embodiments. FIGS. 2A and 2B illustrates
the operation of a clamping mechanism of the invention that
prevents the recording medium from rattling within the cartridge.
The cartridge further comprises a recording medium 70, including a
platter 72 that is fixed to a hub 74, a clamping mechanism 10, and
an arm 58. Clamping mechanism 10 is disposed within a center hollow
77 of hub 74, and arm 58 is coupled between door 23 and clamping
mechanism 10. As a result of the coupling of arm 58 to door 23,
when door 23 moves in the direction indicated by arrow 202, the arm
58 moves concurrently. This movement of door 23 and arm 58 actuates
clamping mechanism 10 between positions A (shown in phantom) to
clamp medium 72 against cartridge shell 12 or B to release
recording medium 72.
[0034] Clamping mechanism 10 generally comprises two members 36,
42--one stationary and another movable. The present invention
contemplates two configurations for clamping mechanism 10. In the
first configuration member 36 is stationary, e.g., fixed to shell
11, and member 42 rotates around stationary member 36.
Alternatively, in another configuration, member 42 is stationary
(e.g., fixed to shell 11) and movable member 42 rotates within
stationary member 36. Exemplary embodiments of these two
configurations, as well as others, are provided herein below. In
either configuration, the movable member is coupled to door 23 via
arm 58. The movable member translates the motion of door 23 into an
rotary motion about the other member so that the movable member is
thereby translated axially. The axial motion provides a force
within hub 74 to clamp against shell 12.
[0035] As shown in the figures, arm 58 (including specific
embodiments 58a,b,c,d) preferably is able to flex so that an end
that is coupled to the movable member may easily move axially with
the movable member. Further, arm 58 is operationally coupled to
door 23, which includes a catch (not shown). The drive engages the
catch as the cartridge enters the drive so as to pull the door
along the side of the cartridge. Preferably the catch is pulled
along the outside of the cartridge. The present invention
encompasses doors having a catch formed integrally thereon and
doors having a catch that are attached thereon as a separate member
or strap, and encompasses doors that travel along the inside wall
of the cartridge and that travel along the outside wall when the
door is proximate its fully open position.
[0036] As will be described fully below, screw 36a, nut 42b, nut
42c, post 108, and stationary member 36a' are provided as examples
of stationary members according to the present invention. Nut 42a,
screw 36b, screw 36c, the assembly comprising coil 96 and plate
102, and movable member 42a' are provided as examples of movable
members according to the present invention. Other embodiments of
stationary and movable members within the scope of the present
invention will be apparent to those generally familiar with
cartridges.
[0037] Referring to FIGS. 3A, 3B, 4 and 5 to illustrate a first
embodiment of the present invention, a clamping mechanism 10a is
actuated as the door 23 is opened and closed. Mechanism 10a, which
is rotatable on the same axis 56 on which a recording medium
rotates, comprises a screw 36a, a nut 42a, and a coil spring 46a,
and is coupled to an actuating arm 58a.
[0038] Screw 36a comprises a post 40a and screw threads 38a.
Preferably, post 40a is rigidly connected to planar surface 18
opposite spindle motor aperture 21 disposed in planar surface 19.
Post 40a may be integrally molded into planar surface 18 in one
piece, or may be formed as a separate piece and connected to
surface 18 by welding or gluing, or by a screw through surface 18
and into post 40. Screw threads 38a, preferably three or four, are
disposed on post 40a, preferably in a helical pattern. Post 40a has
a post slot 52 disposed therein that may be formed as a recess or
slotted hole. FIG. 4 shows screw 36a with exemplary threads 38a and
slot 52a in greater detail.
[0039] Nut 42a, which is preferably shaped as a hollow cylinder
with and open end and a closed, comprises nut threads 44a, a
clamping surface 43a, and a nut slot 54. Nut threads 44a preferably
are disposed on the inside surface of nut 42a. Clamping surface 43a
is disposed on nut 42a proximate the recording medium 70, as will
be described below. FIG. 5 shows an enlarged view of the nut slot
54.
[0040] Actuating arm 58a, which is also shown in FIG. 12, includes
a door end 60a for coupling arm 58a to door 23, and a clamp
mechanism end 62.
[0041] Coil spring 46a is preferably a helical spring, preferably
having several turns, that has a first end 48a and a second end
50a, each of which are bent substantially radially from the coil.
Spring 46a is disposed around post 40a, preferably proximate shell
surface 18. Spring end 48a is disposed in post slot 48a and spring
end 50a is disposed in nut slot 54. Spring 46a provides torsion
(the direction of which depends on the orientation of threads 38a
and 44a) so as to rotate nut 42a in a direction that translates nut
42a away from shell surface 18 and into contact with recording
medium 70.
[0042] FIG. 3A shows the clamping mechanism 10a in a retracted
position corresponding to the cartridge door 23 in an open
position. Nut 42a is threaded onto screw 36a such that nut 42a is
in its fully retracted position, and closest to shell planar
surface 18. Coil spring 46a is urging nut 42a to unscrew from screw
36a, but is unable to produce motion because door 23 is held open
by a mechanism within the drive (not shown). Recording medium 70 is
unencumbered from both clamping mechanism 10a and shell surfaces 18
and 19 so that a drive spindle motor (not shown), which accesses a
disk hub 74 at surface 76b through aperture 21, may spin recording
medium 70.
[0043] When the cartridge is to be removed from the drive, spring
46a urges nut 42a to screw away from planar surface 18 and to clamp
against recording medium 70. Spring 46a may provide sufficient
torsion to drive nut 42a and to drive door 23 from its open to its
closed position, or a mechanism within the drive may help drive the
door closed, and therefore augment the torsion of spring 46a. FIG.
3B shows clamping mechanism 10a in an expanded position
corresponding to cartridge door 23 in a fully closed position. Nut
42a has been fully rotated by door 23 such that nut 42a has
translated axially away from surface 18. Clamping surface 43a urges
against hub contact surface 76a to force hub 74 against shell
surface 19 so as to clamp recording medium 70 against the shell
half 12.
[0044] Referring to FIGS. 6A and 6B to illustrate a second
embodiment of the present invention, a clamping mechanism 10b is
similar to first embodiment clamping mechanism 10a in that there is
one stationary threaded part and one movable threaded part.
Clamping mechanism 10b comprises a screw 36b, a nut 42b, and a coil
spring (which is similar to spring 46a shown in FIGS. 3A and 3B,
but which is omitted from FIGS. 6A and 6B for clarity), and is
coupled to an actuating arm 58b. Unlike mechanism 10a, nut 42b is
stationary and screw 36b rotates and translates on nut 42b.
[0045] Nut 42b comprises nut threads 44b and a door slot 45. Nut
42b is preferably shaped as a hollow, short cylinder with and open
end and another end that is rigidly connected to planar surface 18
opposite spindle motor aperture 21. Nut 42b may be integrally
molded into planar surface 18 in one piece, or may be formed as a
separate piece and connected to surface 18 by welding or gluing, or
by several screws (not shown) through surface 18 and into nut 42b.
Door slot 45 provides an open portion on the side of nut 42b to
provide access to screw 36b by arm 58b. Nut threads 44b preferably
are disposed on the inside surface of nut 42b. FIG. 7 shows an
enlarged view of nut 42b.
[0046] Screw 36b comprises a post 40b, screw threads 38b, and
movable clamping surface 43b. Screw threads 38b, preferably three
or four, are disposed on post 40a, preferably in a helical pattern.
Screw threads 38b are shown schematically in FIG. 6A to illustrate
that the present invention encompasses a groove (generally located
similar to threads 38b) that receives a protruding thread 44b as
shown in FIG. 7. Post 40a has a post slot 52 (not shown for
clarity) disposed therein that may be formed as a recess or slotted
hole. Screw 36b interacts with nut 42b by screwing nut threads 38b
in mesh with threads 44b. Clamping surface 43b is disposed on screw
36b proximate the recording medium 70, as will be described
below.
[0047] Actuating arm 58b, which is also shown in FIG. 12, includes
a door end 60b for coupling arm 58b to door 23, and a clamp
mechanism end 62b. The coil spring (not shown) is disposed
substantially between screw 36b and nut 42b, and provides torsion
to rotate screw 36b away from planar surface 18.
[0048] FIG. 6A shows the clamping mechanism 10b in a retracted
position corresponding to the cartridge door 23 in an open
position. Screw 36b is threaded into nut 42b such that screw 36b is
in its fully retracted position, and closest to shell planar
surface 18. The coil (not shown) is urging screw 36b to unscrew
from nut 42b, but is unable to produce motion because door 23 is
held open by a mechanism within the drive (not shown). Recording
medium 70 is unencumbered in this position and may spin freely, as
described above.
[0049] When the cartridge is to be removed from the drive, the
spring (not shown) urges screw 36b to screw away from planar
surface 18 and to clamp against recording medium 70. The spring
(not shown) may provide sufficient torsion to drive screw 36b and
to drive door 23 from its open to its closed position, or a
mechanism within the drive may help drive the door closed, and
therefore augment the torsion of the spring (not shown). FIG. 6B
shows clamping mechanism 10b in an expanded position corresponding
to cartridge door 23 in a fully closed position. Screw 36b has been
full rotated by door 23 such that screw 36b has translated axially
away from surface 18. Clamping surface 43b urges against hub
contact surface 76a to force hub 74 against shell surface 19 so as
to clamp recording medium 70 against the shell half 12.
[0050] Referring to FIGS. 8A, 8B, and 9 to illustrate a third
embodiment of the present invention, a clamping mechanism 10c
comprises a screw 36c, a nut 42c, and a helical spring 90, and is
coupled to an actuating arm 58c.
[0051] Screw 36c comprises a cylindrical portion 80, an internal
flange 82, a contact shoulder 43c, screw threads 38c, and a screw
spring anchor 86 (shown in FIG. 9). Screw 38c is preferably open at
both ends of cylindrical portion 80, and has an internal flange 82
disposed on the spindle motor side of cylindrical portion 80.
Contact shoulder 43c is formed on the interior upper surface of
flange 82. Threads 38c are sized to mesh with nut threads 44c. The
interior upper corners of flange 82 and the corresponding corners
of disk hub 74 may be beveled (not shown) to provide self-alignment
during clamping. Referring specifically to FIG. 9, spring anchor 86
comprises a radial tab on the exterior portion of cylindrical
portion 80. Alternatively, spring anchor 86 may be formed on arm
58c.
[0052] Nut 44c, which preferably is formed on the rim of second
surface 19 formed by aperture 21, comprises nut threads 44c. The
invention also encompasses providing a shell having a thickened
portion in the rim region in the direction of axis of rotation 56
to provide greater depth for threads 44c. Further, nut threads 44c
may be finer and more numerous than corresponding threads 44a and
44b because of the comparatively lesser depth.
[0053] Helical spring 90 is disposed between an anchor 84 (shown in
FIG. 9), which is fixed to surface 19, and anchor 86, and biases
screw 36c toward the clamped, upward direction. Proximate one point
on the circumference of nut 42c, an arcuate spring retainer 92 is
formed to prevent spring 90 from bowing in the radial direction,
although spring 90 may be designed such that it is under constant
tension. Preferably, retainer 92 comprises an arcuate wall and a
recessed portion 91 of surface 19 that provides a space to house
spring 90. Because spring 90 is partially within recessed portion
91, the retainer 92 is shorter and the vertical dimension of spring
90 over surface 19 is diminished.
[0054] FIG. 8A shows the clamping mechanism 10c in a retracted
position corresponding to the cartridge door 23 in an open
position. Screw 36c is threaded into nut 42c such that nut 42c is
in its fully retracted position, and farthest from shell planar
surface 18. Helical spring 90 biases screw 36c to rotate and
translate toward the clamped position. Spring 90 may provide
sufficient torsion to drive nut 42c and to drive door 23 from its
open to its closed position, or a mechanism within the drive may
help drive the door closed, and therefore augment the torsion of
spring 90.
[0055] FIG. 8B shows clamping mechanism 10c in a clamped position
corresponding to cartridge door 23 in a fully closed position.
Screw 36c has been fully rotated by door 23 such that screw 36c has
translated axially toward recording medium 70. Contact surface 70
urges against hub contact surface 76a to force hub 74 against shell
surface 18 so as to clamp recording medium 70 against the shell
half 11.
[0056] Referring to FIGS. 10A, 10B, and 11 to illustrate a fourth
embodiment of the present invention, clamping mechanism 10d
comprises a helical coil 96, a contact plate 102, and a post 108,
and is coupled to actuating arm 58d. Post 108 is fixed to the
surface 18 concentric with axis 56, and may be integrally molded
into planar surface 18 in one piece, or may be formed as a separate
piece and connected to surface 18 by welding or gluing, or by
several screws (not shown) through surface 18 and into post 108.
Post 108 has a longitudinal keyway 110 formed therein that is
disposed on its end opposite its fixed end.
[0057] Helical coil 96, which is substantially concentrically
disposed around the axis of rotation 56, comprises a first end 98
that is coupled to actuating arm 58d at a central circular potion
61 proximate surface 18, and a second end 100 that is coupled to
plate 102.
[0058] Plate 102 is preferably a circular disk that is rigidly
coupled to the second end 100 of coil 96, and has center cutout
portion 103 and a key portion 106 that protrudes into center cutout
103 and that is insertable into keyway 110 in the post 108. Key 106
may slide freely longitudinally within keyway 110, and plate 102
preferably is perpendicular to axis 56. Plate 102 has a contact
surface 43d disposed on its side facing recording medium 70.
[0059] Actuating arm 58d, which is also shown in FIG. 12, includes
a door end 60d for coupling arm 58d to door 23, a circular portion
disposed substantially concentric with post 108, and a clamp
mechanism end 62d. Arm 58d is movably fixed to shell surface 18 in
a way that enables arm 58d to rotate or pivot, but which keeps arm
58d substantially flat against surface 18. For example, multiple
retainer clamps 63, shown in relief in FIG. 10A may be used at
points around the circumference of the circular portion of arm 58d
to prevent arm 58 from moving away from surface 18 yet enable arm
58 to rotate or pivot around post 108.
[0060] FIG. 10A shows the clamping mechanism 10d in a retracted
position corresponding to the cartridge door 23 in an open
position. Plate 102 is in its closest position to surface 18 with
coil 96 connected between arm 58d and plate 102. Plate 102 is at
rest on top of coil 96 with key 106 disposed in keyway 110.
Recording medium 70 is unencumbered in this position and may spin
freely, as described above.
[0061] When the cartridge is to be removed from the drive, arm 58d
rotates or pivots around axis 56 in response to the door moving in
a closing direction. FIG. 10B shows clamping mechanism 10d in an
expanded position corresponding to cartridge door 23 in a fully
closed position. As door 23 closes, movement of arm 58d results in
rotation of coil 96 in a direction that urges plate 102 to
translate toward recording medium 70 along post 108. Plate 102
translation occurs in response to coil 96 rotation because plate
102 is prevented from rotating by key 106. Plate 102 moves toward
recording medium 70 until contact surface 43d on plate 102 contacts
a hub contact surface 105, which may be disposed on a hollow,
longitudinally protruding portion 107 of hub 74. A shown in FIG.
10A, post 108 may be disposed within the hollow portion of
protruding portion 107 while the cartridge is in the unclamped
position. Therefore, adequate clearance between post 108 and the
interior of protruding portion 107 so as to enable recording medium
70 to rotate freely during drive operation. When the door is in its
fully closed position, contact surface urges against surface 105
and hub contact surface 76b urges against shell surface 19 so as to
clamp recording medium 70. Although clamp mechanism 10d is
illustrated using a disk hub having a protruding portion, clamp
mechanism 10d according to the present invention may also be
employed with disk hubs having a cavity, as shown in the first two
embodiments.
[0062] Although the first three embodiments have been described
using threads on both the stationary and movable members, the
present invention encompasses using other designs to translate the
movable member in response to rotation by the actuating arm. FIGS.
13, 14, and 15 illustrate an alternate assembly that is similar to
the first embodiment shown in FIGS. 3A and 3B, and that may be used
to form the movable and stationary members according to the present
invention Specifically, a clamping mechanism 10a' may be used in
place of screw 36a and nut 42a shown in FIGS. 3A and 3B. Recording
medium 70, spring 46a, and surface 19 have been omitted from FIG.
13 for clarity.
[0063] Clamping mechanism 10a' comprises a stationary member 36a',
a movable member 42a', and is coupled to door 58a. Stationary
member 36a' comprises a post 40a' that is rigidly fixed to surface
18 and plural pins 114 extending substantially radially from post
40a'. Movable member 42a' comprises a hollow cylinder with a
helical groove 116 formed on the inside surface capable of
receiving pins 114.
[0064] In response to movement of door 23, movable member 42a'
rides on pins 114 to translate relative to stationary member 36s',
similar to as described with respect to the first embodiment.
[0065] Nuts 42a,b,c interact with screws 36a,b,c by screwing nut
threads 44a,b,c in mesh with screw threads 38a,b,c with adequate
clearance therebetween such that threads 38a,b,c and 44a,b,c do not
deform. Such a clearance enables nut 42a, screw 36b, and nut 42c to
rotate and translate on screw 36a, nut 42b, and screw 36c with a
minimum amount of rotational force applied thereto.
[0066] Actuating arm 58a,b,c,d may include a telescoping wire 64
disposed in a recess opening 62 in arm 58a,b,c,d, as more fully
described in U.S. Pat. No. 5,560,899-Schick et al. to the present
assignee, which is incorporated herein by reference in its
entirety.
[0067] Although the present invention has been described with
reference to a cartridge in which a flexible door travels along a
radius of curvature that changes by angular position (that is, as
shown in FIG. 1A), the present invention encompasses a cartridge in
which a rigid door travels along an arc of constant radius. In the
latter design, the door may be formed of rigid plastic or metal in
a circular arc that travels in the circular track, and the
actuating arm may span the entire arcuate segment of the door to
form substantially a radial portion of a circle.
[0068] The terms "axial" and "axially" as used herein refer to an
axis of rotation of the recording medium. The term "longitudinal"
when used herein to any part of the clamping mechanism, refers to a
direction or orientation substantially parallel to the axis of
rotation of the recording medium.
[0069] While a particular embodiment has been shown and described
various modifications may be made. The appended claims are,
therefore, intended to cover all such modifications within the true
spirit and scope of the invention.
* * * * *