U.S. patent number RE41,401 [Application Number 10/631,993] was granted by the patent office on 2010-06-29 for magnetic head suspension assembly fabricated with integral load beam and flexure.
This patent grant is currently assigned to Western Digital (Fremont), LLC. Invention is credited to Michael R. Hatch, Chak M. Leung.
United States Patent |
RE41,401 |
Hatch , et al. |
June 29, 2010 |
Magnetic head suspension assembly fabricated with integral load
beam and flexure
Abstract
A magnetic head suspension assembly is fabricated with an
integral piece which includes a load beam section, a flexure
section, a rear mount section and a leaf spring section between the
load beam and rear mount. A tongue extends from the load beam to
the flexure and has a down-facing load dimple which contacts the
non-air bearing surface of an attached air bearing slider. The
flexure includes narrow thin legs adjacent to a cutout that
delineates the load beam tongue. The head suspension is
characterized by a high first bending mode frequency and low pitch
and roll stiffness.
Inventors: |
Hatch; Michael R. (Mountain
View, CA), Leung; Chak M. (Palo Alto, CA) |
Assignee: |
Western Digital (Fremont), LLC
(Fremont, CA)
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Family
ID: |
26719766 |
Appl.
No.: |
10/631,993 |
Filed: |
July 30, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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08521786 |
Aug 31, 1995 |
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07958516 |
Oct 7, 1992 |
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Reissue of: |
08042906 |
Apr 5, 1993 |
05282103 |
Jan 25, 1994 |
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Current U.S.
Class: |
360/245;
360/245.5; 360/245.8; 360/244.5; 360/244.2; 360/244.3 |
Current CPC
Class: |
G11B
5/4833 (20130101) |
Current International
Class: |
G11B
5/48 (20060101) |
Field of
Search: |
;360/245,244.2,244.3,244.5,245.5,245.8 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Klimowicz; William J
Parent Case Text
This application is a continuation-in-part of application Ser. No.
07/958,516, filed Oct. 7, 1992, now abandoned.
Claims
What is claimed is:
1. A .[.magnetic.]. head suspension assembly .[.including.].
.Iadd.comprising:.Iaddend. an air bearing slider .[.and.].
.Iadd.having .Iaddend.at least one transducer .[.disposed on said
slider.]. .Iadd.mounted thereon .Iaddend.for transducing data that
is recorded and read out from a surface of a rotating magnetic
.[.disk drive comprising:.]. .Iadd.disc;.Iaddend. a single
.[.integral planar.]. piece .[.of a specified thickness.]. .Iadd.of
material .Iaddend.comprising.[.,.]. .Iadd.:.Iaddend. a load beam
section formed with a narrowed end; a flexure section .[.formed
with.]. .Iadd.having a shaped opening which defines .Iaddend.two
.[.spaced narrow legs defining a cutout portion therebetween, said
legs extending.]. .Iadd.flexure beams that extend in a longitudinal
direction .Iaddend.from said narrowed end of said load beam
section, .[.and a lateral ear spaced.]. .Iadd.said flexure section
further including a transverse section spaced in said longitudinal
direction .Iaddend.from said load beam section.Iadd., said
transverse section .Iaddend.connecting said .[.legs.].
.Iadd.flexure beams.Iaddend.; a .Iadd.load point .Iaddend.tongue
extending from said .Iadd.narrowed .Iaddend.end of said
.[.narrowed.]. load beam section .Iadd.into said shaped opening
such that said flexure beams and load point tongue lie
substantially in the same plane.Iaddend., said .Iadd.load point
.Iaddend.tongue being disposed .Iadd.substantially .Iaddend.between
said .[.legs of said.]. flexure .[.section, said tongue.].
.Iadd.beams and .Iaddend.having a free end within said .[.flexure
section,.]. .Iadd.shaped opening, .Iaddend.said .Iadd.load point
.Iaddend.tongue .[.being formed with.]. .Iadd.having .Iaddend.a
load .[.dimple.]. .Iadd.supporting protrusion.Iaddend.; said air
bearing slider being bended to said .[.lateral ear.].
.Iadd.transverse section .Iaddend.and in contact with said load
.[.dimple; whereby load transfer is effectively separated from the
gimballing action of said slider so that pitch and roll stiffness
is effectively reduced.]. .Iadd.supporting protrusion.Iaddend..
2. An assembly as in claim 1, wherein said .[.head.]. .Iadd.air
bearing .Iaddend.slider has a top non-air bearing surface attached
to said .[.flexure section.]. .Iadd.transverse
section.Iaddend..
.[.3. An assembly as in claim 2, including means formed with said
lateral ear for supporting said attached head slider..].
.[.4. An assembly as in claim 3, wherein said supporting means
comprises outriggers or a split tongue..].
.[.5. An assembly as in claim 3, wherein said supporting means
comprises said lateral ear that connects said narrow legs..].
6. An assembly as in claim 2, wherein said .Iadd.air bearing
.Iaddend.slider is about 0.0110 inch high, 0.0400 inch long and
0.0200-0.0260 inch wide.
7. An assembly as in claim 2, wherein said top non-air bearing
surface .[.of said slider.]. is formed with a platform and .Iadd.a
.Iaddend.step adjacent to said platform.
8. An assembly as in claim 7, wherein said platform .[.of said
slider.]. is about 0.0336 inch long and said step is about 0.0015
inch high.
9. An assembly as in claim .[.2, including a load dimple formed in
said tongue.]. .Iadd.1, wherein said beam section and said
transverse section have a first thickness.Iaddend..
10. An assembly as in claim 9, wherein said load .[.dimple.].
.Iadd.supporting protrusion .Iaddend.is hemispherical in shape
.[.and faces down into contact with said top surface of said
slider.]. .
11. An assembly as in claim .[.1, wherein said single integral
planar piece including said tongue is about 0.0012 to 0.0015 inch
thick and said narrow legs are about 0.0010 inch thick.]. .Iadd.9,
wherein said flexure beams have a second thickness which is thinner
than said first thickness.Iaddend..
12. An assembly as in claim 1, wherein said .[.load beam section is
shaped as a truncated triangle.]. .Iadd.flexure beams are
substantially parallel to said longitudinal direction so that said
opening is substantially U-shaped.Iaddend..
13. An assembly as in .[.claim 1,.]. .Iadd.claims 1, 2, 6, 7, 8, 9,
10, 11 or 12, wherein said load beam section has a rear end
opposite said narrowed end, and further including: a leaf spring
section attached at a first end to said rear end of said load beam
section, said leaf spring section providing a load force to said
air bearing slider through said load supporting protrusion;
and.Iaddend. .[.including.]. a mount section .[.at the rear end of
said load beam.]. .Iadd.attached to a second end of said leaf
spring .Iaddend.section for .[.enabling mounting said suspension.].
.Iadd.attachment .Iaddend.to an actuator arm.Iadd...Iaddend..[.;
and a leaf spring section between said rear mount section and said
load beam section for providing flexibility to said
suspension..].
14. An assembly as in claim .[.13.]. .Iadd.1.Iaddend.,
.Iadd.wherein said load beam section has a rear end opposite said
narrowed end and further .Iaddend.including.Iadd.: a leaf spring
section attached at a first end to said rear end of said load beam
section, said leaf spring section providing a load force to said
air bearing slider through said load supporting protrusion; a mount
section attached to a second end of said leaf spring section for
attachment to an actuator arm; and .Iaddend. a swage plate joined
to said mount section for .[.providing rigidity to said rear end of
said suspension assembly.]. .Iadd.attachment to said actuator
arm.Iaddend..
15. An assembly as in claim .[.13, including front flanges formed
along the edges of said load beam section and rear flanges formed
along the edges of said rear mount section with a hiatus between
said front and rear flanges.]. .Iadd.1, wherein said load beam
section has first and second sides, at least one of said sides
having a flange integral therewith.Iaddend..
16. An assembly as in claim 15, wherein .[.said front flanges are
formed with shallow U-shaped channels, and electrical wiring
without tubing is positioned within said channels.]. .Iadd.said
flange comprises a channel which accommodates an electrical
wire.Iaddend..
17. An assembly as in claim .[.13, including a cutout in.].
.Iadd.1, wherein said load beam section has a rear end opposite
said narrowed end and further including: a leaf spring section
attached at a first end to said rear end of said load beam section,
said leaf spring section providing a load force to said air bearing
slider through said load supporting protrusion, wherein
.Iaddend.said leaf spring section .[.for providing flexibility to
said suspension.]. .Iadd.includes a trapezoidal-like opening; and a
mount section attached to a second end of said leaf spring section
for attachment to an actuator arm.Iaddend..
18. An assembly as in claim 1, .[.further including an apertured
extension formed at the rear end of said suspension assembly for
enabling attachment to an actuator of a disk drive without a
separate head arm to enable pivoting of said suspension assembly.].
.Iadd.wherein said load supporting protrusion is located along a
centerline of said air bearing slider.Iaddend..
19. An assembly as in .[.claim 1,.]. .Iadd.claims 1, 2, 6, 7, 8, 9,
10, 11 or 12, further .Iaddend.including a damping .[.material
on.]. .Iadd.element attached to .Iaddend.said load beam
.Iadd.section.Iaddend..
20. An assembly as in claim .[.1.]. .Iadd.15.Iaddend.,
.Iadd.further .Iaddend.including at least one load/unload tab
formed .[.at the sides of said.]. .Iadd.on at least one of said
sides of said .Iaddend.load beam section.
21. An assembly as in claim 2, wherein said top non-air bearing
surface is substantially flat.
22. An assembly as in claim 21, wherein said .[.lateral ear.].
.Iadd.transverse section .Iaddend.includes bent sections for
.[.contacting with said top surface of said slider.].
.Iadd.attachment to said air bearing slider.Iaddend..
.Iadd.23. An assembly as in claim 1 wherein said load point
protrusion is offset a distance from a centerline extending between
said flexure beams..Iaddend.
.Iadd.24. An assembly as in claim 23 wherein said distance is
greater than zero inches, but less than or equal to 0.006
inches..Iaddend.
Description
CROSS-REFERENCE TO COPENDING APPLICATION
.[.Copending.]. U.S. patent application Ser. No. 07/926,033 filed
Aug. 5, 1992.Iadd., now U.S. Pat. No. 5,299,081 issued on Mar. 29,
1994, .Iaddend.is directed to a head suspension assembly
particularly useful with nanosliders, which are about 50% of the
size of the standard full size air bearing sliders. The present
application.Iadd., which is a continuation application of reissue
application Ser. No. 08/521,786 filed Aug. 31, 1995, now abandoned,
which is a reissue of application Ser. No. 08/042,906 filed Apr. 5,
1993, which issued as U.S. Pat. No. 5,282,103 on Jan. 25, 1994,
.Iaddend.which is a continuation-in-part of .[.copending.].
application Ser. No. 07/958,516, now abandoned, discloses a
modified and improved head suspension assembly especially useful
with femtosliders, which are about 25% of the size of the standard
full size sliders. .Iadd.The present application is related to
reissue application Ser. No. 08/662,528, filed Jun. 13, 1996, which
reissued as U.S. Reissued Pat. No. RE39,478 on Jan. 23, 2007, to
reissue application Ser. No. 08/662,531, filed Jun. 13, 1996, now
abandoned, and to reissue application Ser. No. 08/662,885, filed
Jun. 13, 1996, which reissued as U.S. Reissued Pat. No. RE40,203 on
Apr. 1, 2008. .Iaddend.The subject matter of .[.the aforementioned
copending application.]. .Iadd.U.S. Pat. No. 5,299,081 .Iaddend.is
incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a magnetic head suspension assembly that
accommodates air bearing femtosliders which are used in compact
disk drives.
DESCRIPTION OF THE PRIOR ART
Presently known disk drives, such as used in laptop or notebook
computers, include at least one rotatable magnetic disk, at least
one magnetic head assembly for transducing data recorded on the
disk, and a rotary head actuator for transporting the magnetic head
to selected data tracks on the rotating disk. The magnetic head
assembly comprises a head suspension fabricated with a rigid load
beam element and a gimbaling flexure. A typical head suspension
includes a load beam element and a flexure which are fabricated at
separate parts and are then joined during assembly of the head
suspension. Special tooling to implement accurate alignment and
assembly of the load beam and flexure is required. After joinder of
the load beam element and flexure, an air bearing slider is mounted
at the end of the flexure. The slider supports a thin film magnetic
transducer which coacts with the magnetic disk for recording or
reading data signals.
During operation of the disk drive, the rotating magnetic disk
provides an aerodynamic lift force to the slider, while an opposing
gram load force is applied to the slider through the flexure. The
resultant of the two opposing forces determines the flying height
of the slider and its transducer relative to the disk surface. In
its operating flying mode, the slider gimbals about a .[.load
dimple.]. .Iadd.protrusion, commonly known as a load dimple,
.Iaddend.formed in the flexure.
In known prior art head suspension and flexure designs, the load
force transfer and gimbaling action are separate to provide high
first bending frequency with low pitch and low stiffness. The
flexure participates slightly in the load transfer with the load
beam while primarily providing the low pitch and roll stiffness
gimbaling action and providing high stiffness for lateral motion.
These suspensions are characterized by weak pitch, roll and bending
stiffness when the head is flying over the disk surface. For
optimum functioning, however, the suspension structure should
provide a high first bending mode resonant frequency so that the
slider can follow variations in the topography of the rotating disk
surface while providing low pitch and roll stiffness.
Another objective in the design of compact disk drives which are
used in laptop or notebook computers is to minimize the size and
mass of the drive components. A reduction in Z-height (vertical
height) of the suspension and slider assembly results in a
corresponding reduction in the Z-height of the compact disk drive
incorporating the assembly. A standard full size slider is about
0.160 inch long, 0.125 inch wide and 0.0345 inch high. Presently
known disk drives employ nanosliders that measure approximately
0.080 inch long, 0.063 inch wide and 0.017 inch high, which size is
about 50% of the size of a standard slider. The novel suspension
and slider design disclosed herein is particularly useful for
femtosliders, which measure about 0.040 inch long, 0.020-0.026 inch
wide and 0.0110 inch in overall height, which size is about 25% of
the size of a standard full size slider. It should be understood
that the novel design may be used with other size sliders as
well.
SUMMARY OF THE INVENTION
An object of this invention is to provide a head suspension and
slider assembly having significantly reduced Z-height.
Another object of this invention is to provide a head suspension
assembly characterized by low pitch and roll stiffness.
Another object is to provide a head suspension assembly
characterized by low bending stiffness with decreased gram load
tolerance effects.
Another object is to provide a head suspension assembly
characterized by a relatively high first bending mode, first
torsion mode, and first lateral mode resonant frequencies.
A further object is to provide a head suspension design that
affords significant savings and advantages in manufacture and mass
production.
According to this invention, a magnetic head suspension assembly is
formed from an integral planar piece comprising a load beam section
and flexure section. The load beam is configured preferably as a
truncated conical section having flanges along its sides and an
extending tongue at its narrow end. The side flanges are formed
with U-shaped channels and provide rigidity and stiffness to the
load beam section. The load beam tongue extends .[.into the flexure
section and is formed with a hemispherical load dimple which faces
down to the non-air bearing surface of a head slider. A U-shaped
cutout portion that is formed in the flexure section adjacent to
the load beam tongue delineates the shape of the tongue. In one
embodiment of the invention, the flexure section includes two
narrow etched legs that extend from the load beam and are disposed
adjacent to the cutout portion. The narrow legs are connected by a
lateral ear at the end of the flexure.]. .Iadd.from the narrow end
of the load beam section into a shaped opening of the flexure
section. The load beam tongue is formed with a load supporting
protrusion or dimple that extends downward to contact a non-air
bearing surface of a head slider. The shaped opening defines two
flexure beams that extend in a longitudinal direction of the load
beam. The flexure beams are connected by a transverse section at
the end of the flexure section opposite the narrow end of the load
beam section.Iaddend.. In this implementation, the head slider is
bonded to the bottom surface of the .[.lateral ear.].
.Iadd.transverse section.Iaddend.. In an alternative embodiment,
the flexure section includes outriggers configured as a split
tongue to which the slider is bonded.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in greater detail with reference to
the drawings in which:
FIG. 1A is a top plan view of a head suspension and slider
assembly, made in accordance with this invention;
FIG. 1B is a front elevational view of the head suspension of FIG.
1;
FIG. 2 is a side elevation view of the assembly of FIG. 1, showing
a head slider attached to the end of the flexure, in a loaded
position and in phantom in an unloaded position;
FIG. 3 is a bottom view of the head suspension of FIG. 1;
FIG. 4 is a side elevation view of the assembly of FIG. 3, showing
the load dimple without an attached slider;
FIG. 5A is an enlarged view of a portion of the head suspension of
FIG. 3;
FIG. 5B is a front elevation view of the head suspension of FIG.
5A;
FIG. 6A is an enlarged view of a portion of a head suspension and
flexure incorporating an alternative design;
FIG. 6B is a front elevation view of the head suspension portion of
FIG. 6A;
FIG. 6C is a representational front view showing the overhang of
the outriggers of FIG. 6A relative to a slider;
FIG. 7 is a side elevation view of a portion of the head suspension
shown in FIG. 6A;
FIG. 8 is a plan sectional representation of a paddle board or fret
illustrating three of a multiplicity of head suspension bodies
stamped from a piece of stainless steel;
FIG. 8A is a side elevation view of the paddle board of FIG. 8;
FIG. 9 is a top plan view of a nanoslider suspension, such as
disclosed in the aforementioned copending application;
FIG. 10 is a top plan view of a femtoslider suspension, with an
extended part to enable handling during production;
FIG. 11 is a top plan view of the femtoslider suspension of FIG. 10
with a skewed configuration relative to the extension;
FIG. 12 shows the femtoslider suspension without the extension for
the purpose of illustrating the relative sizes of the nanoslider
suspension and the femtoslider suspension;
FIG. 13 is a top plan view of a femtoslider suspension, partly
broken away, including load/unload side tabs;
FIG. 13A is a section A--A taken through FIG. 13;
FIG. 14A is a top view of the flexure of the suspension, partly
broken away, showing a stepped flexure;
FIG. 14B is a side view of the flexure of FIG. 14A;
FIG. 14C is a front view of the flexure of FIG. 14A. Similar
numerals refer to similar elements in the drawing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 1A-5B, a magnetic head suspension assembly
includes a load beam section 10, a flexure section 12, a leaf
spring section 56 and a rear mount section 42. The suspension is
formed from an integral flat piece of nonmagnetic material,
preferably a 300 Series type stainless steel having a thickness of
about 0.0012 to 0.0015 inch. As a result of using an integral
piece, the load beam section 10 and flexure section 12, as well as
the leaf spring section 56 and rear mount section 42, are disposed
substantially in a single plane. No separate forming of individual
load beam and flexure parts is required. Therefore, no assembly
steps of joining and welding are needed for attaching the flexure
to the load beam.
The load beam section 10 is preferably made in a truncated conical
or triangular shape. The load beam section has a short tapered
tongue 14 extending from .[.its relatively narrow end into the
flexure section 12. The tongue 14 is delineated by a U-shaped
cutout 16 in the flexure section.]. .Iadd.the relatively narrow end
of the load beam section into a shaped opening 16 of flexure
section 12. The tongue 14 delineates the U-shape of the opening
16.Iaddend.. The load beam tongue 14 provides low deflections in
the direction orthogonal to the plane of the load beam section and
flexure section by virtue of its short length and low gram load
force.
A constrained layer damping element 19 made of elastomer 10A about
0.002 inch thick and an overlay 10B of about 0.002 inch thick
stainless steel is laid down on the top surface of the major
section of the load beam to minimize undesirable resonances of the
suspension, as shown in FIG. 1. Alternatively, a similar damping
element 21 may be deposited on the bottom surface of the load beam
without interfering with the flexure 12, as shown in FIG. 3.
The flexure section 12 includes .[.narrow legs 32 that are located
adjacent to the sides of the U-shaped cutout 16. The flexure legs
32.]. .Iadd.flexure beams 32 defined by shaped opening 16. The
flexure beams 32 .Iaddend.are chemically etched to a thickness of
about 0.0010 inch for increased flexibility. The .[.narrow legs 32
are.]. .Iadd.flexure beams 32 are narrow, .Iaddend.thin and
relatively weak to allow the desired gimbaling action about the
load dimple 18 and also to allow the suspension to have low roll
and pitch stiffness. A lateral connecting part or .[.ear.].
.Iadd.transverse section .Iaddend.38 is formed with the integral
flat load beam and flexure to connect ends of the .[.narrow legs.].
.Iadd.flexure beams .Iaddend.32.
In this implementation of the invention, a slider 22 is bonded to
the lateral connecting part 38. A hemispherical load dimple 18 is
formed on the load beam tongue 14 and is in contact with the top
non-air bearing surface of an air bearing slider 22 that is bonded
to the lateral part or .[.ear.]. .Iadd.transverse section
.Iaddend.38. The load dimple 18 is formed so that the hemisphere of
the dimple faces down to the slider. The dimple 18 may be offset,
0-0.006 inch for example, from the centerline of the slider in
order to control flying height characteristics.
U-shaped flanges 24 extend along the sides of the load beam section
and are truncated before reaching the flexure section 12. The
flanges 24 contribute to the stiffness of the load beam section and
localize.[.s.]. the bending action to the spring section 56,
thereby minimizing the pitch attitude changes due to arm/disk
vertical tolerances. Head circuitry wiring 92 without the
conventional tubing is located within the channels of the flanges
24. The absence of tubing allows the U-shaped channels of the
flanges 24 to be relatively shallow thereby contributing to the
reduction of the Z-height of the head suspension assembly. Adhesive
material 90 is used to maintain the wiring 92 fixed in place.
Adhesive fillets 91 are provided adjacent to the .[.ear.].
.Iadd.transverse section .Iaddend.38 and the slider 22. The fillets
91 are exposed and thus can be cured easily by application of
ultraviolet radiation.
In a disk drive using this head suspension and slider assembly,
flexing occurs between the load beam tongue 14 and the flexure legs
32. With this design, the load force is transferred through the
tongue 14 to the truncated conical section of the load beam. This
integral load beam/flexure configuration allows the separation of
the applied load transfer force from the gimbal action so that the
structure may be made stiff at the load beam for proper bending and
relatively weak about the load dimple to allow proper pitch and
roll of the slider.
A feature of the head suspension and slider assembly disclosed
herein is that the slider 22 is configured with a step 28, which is
formed by cutting a recessed portion or platform 30 on the non-air
bearing top surface of the slider 22. The Z-height of the step 28
is substantially the same as the Z-height of the hemisphere load
dimple 18. Sufficient spacing is provided between the load beam
tongue 14 and the top slider surface to allow free gimbaling action
of the slider 22 with no interference from the load beam. The
slider step 28 is sufficiently high so that the slider end at the
trailing edge can accommodate a thin film magnetic transducer
including its coil turns.
The leaf spring 56 between the load beam section 10 and the rear
mount section 42 is formed with a trapezoidal-like .[.cutout.].
.Iadd.opening .Iaddend.60 to provide flexibility. The flexible
section 56 is formed to provide a desired load force that
counteracts the aerodynamic lift force generated by the rotating
disk during operation of the disk drive. The load force arises from
bending the suspension from the phantom position, shown in FIG. 2,
to the raised position as indicated by the arrow.
The rear mount section 42 of the load beam 10 has a hole 48 to
allow connection of a swage plate 46 to the suspension by means of
a boss 48 and by laser welding. The swage plate 46 provides
stiffness to the rear mount section 42. Rear flanges 54 provide
wire routing channels to protect the wires during handling.
The head suspension and slider assembly described herein
incorporates a stiff load beam and a relatively long and narrow
flexure which includes thin weak flexure legs and connecting
lateral part. With this design, low bending stiffness and high
lateral and longitudinal stiffness with low roll and pitch
stiffness are realized. The load beam tongue has a high vertical or
perpendicular stiffness so that there is minimal bending of the
load beam tongue up or down relative to the plane of the
suspension. The first bending mode resonant frequency or vibration
is substantially higher than known prior art suspension designs of
comparable size.
In an actual implementation of this invention, the overall height
of the slider is about 0.0110 inch, its length about 0.0400 inch,
and its width about 0.020 inch. The height of the step 28 is about
0.0015 inch above the recessed portion 30 which is 0.0336 inch
long. The surface area of the top of the step 28 is preferably
minimized in size to reduce the effects of bending or warping at
the surface of the slider step which may occur due to the
difference in the thermal coefficients of expansion of the ceramic
slider 22 and the stainless steel .[.ear.]. .Iadd.transverse
section .Iaddend.38. Such bending would affect the flying
characteristics of the head adversely.
In an alternative embodiment of the head suspension, illustrated in
part in FIGS. 6A-7, the flexure section 62 is formed with a tongue
64 and a .[.cutout.]. .Iadd.shaped opening .Iaddend.66. A
down-facing load dimple 76 is provided on the tongue 64. .[.Narrow
etched legs.]. .Iadd.Narrow, thinly etched flexure beams
.Iaddend.68 that extend from the load beam 10 are connected by a
transverse part 70. The .[.legs.]. .Iadd.flexure beams .Iaddend.68
are chemically etched to be thinner than the integral flat piece
used to form the load beam and flexure sections. Outriggers 72
forming a split tongue are provided at the sides of the flexure 62
and are separated from the thin .[.legs.]. .Iadd.flexure beams
.Iaddend.68 by .[.cutouts.]. .Iadd.spaces .Iaddend.74. The
outriggers 72 overhang the sides of the slider 22 and the slider is
fastened to the outriggers by .[.an.]. adhesive fillet.Iadd.s
.Iaddend..[.90.]. .Iadd.61.Iaddend.. In this implementation, the
top non-air bearing surface 20 of the slider 22 is bonded to the
outriggers 72 by adhesive fillets .[.which provide bond strength at
the cutout 16,.]. .Iadd.61 which provide bond strength .Iaddend.as
shown in FIG. 6C. The slider 22 is mounted to the outriggers 72 so
that the center of the slider is aligned with the load dimple 76,
and the slider projects beyond the end of the transverse part 70.
There is no offset of the load dimple 76 relative to the centerline
of the slider. With this implementation, a lower vertical height
(Z-height) is realized. Also the slider bonding areas of the
outriggers 72 are larger than the bonding area of the lateral
connecting part 38 of flexure 12 of FIG. 1. In this implementation,
there is little room to move the slider toward the leading edge
relative to the load dimple, which may be necessary to obtain
optimal flying attitude. Also, additional forming is required in
order to bend the two outrigger legs 72 down to the bend 20, which
increases the tolerances during production.
FIG. 8 shows a paddleboard or fret 80 formed from a stainless steel
piece that has been stamped with a number of head suspensions 82,
each of which was formed with the design shown in FIG. 1. Tooling
holes 84 and support legs 86 are provided for further handling.
FIG. 8A shows the paddleboard 80 with support legs 86 bent to
enable working on the extremely small femtoslider suspensions.
FIG. 9 shows a nanoslider suspension such as disclosed in copending
application Ser. No. 07/926,033. The nanoslider includes a load
beam 94, flexure 96, load beam tongue 98, spring section 100, rear
mount section 102 and slider 104.
FIGS. 10 and 11 illustrate the femtoslider suspension of this
invention with the load beam 10, flexure 12, spring section 56 and
a rear section having a tooling hole 106. The tooling hole section
106 is attached to an extension 108 formed with an apertured swage
110 that allows attachment to a rotary actuator. In effect for
extremely small drives, such as 1.3 inch and smaller, the extension
108 serves as an arm pivot and precludes the need for a separate
arm structure, as used in the prior art. The extension 108 also
allows the assembly to match the overall length of other industry
standard "70%" microslider suspensions, thereby making it easy to
use existing tooling.
FIG. 11 shows the suspension skewed with relation to the extension
108 to compensate for skew experienced as the head moves between
the outer diameter and the inner diameter of the disk during
accessing. The extension may include apertures 112 for weight
reduction, as shown in FIGS. 10 and 11. The apertures 112 serve to
adjust for resonant conditions and/or to adjust for total actuator
balance about the pivot.
FIG. 12 illustrates the femtoslider suspension without the
extension and shows the large difference in size between the
nanoslider and femtoslider suspensions. In an implementation of the
femtoslider, the length was about 0.395 inch and the greatest width
was about 0.056 inch.
With reference to FIGS. 13 and 13A, a head slider suspension
includes flat side tabs 120 which protrude to enable loading and
unloading of the head suspension assembly relative to the surface
of a magnetic disk in a disk drive. The side tabs may be present on
one or both sides of the load beam. The side tabs 120 are moved by
means of a tool for lifting or lowering the suspension assembly.
The addition of the flat side tabs which are in the same plane as
the load beam does not add to the vertical Z-height of the
suspension assembly.
FIGS. 14A-C depict a partial suspension assembly having a slider
122 and a thin film transducer 124 at a slider end. The slider 122
has a flat top surface 126 on which the load dimple 76 is seated.
The slider 122 is not formed with a step 78, as shown in the slider
design of FIG. 7. The flat surface 126 extends across the entire
top of the slider. However, the front end of the flexure 120 is
bent at sections 130 and 132, as shown in FIG. 14B to allow the
flexure to come down by a distance substantially equivalent to the
height of the load dimple 76. In this way, the flexure 128 contacts
the flat top surface 126 of the slider 122. The slider is bonded to
the bent sections 130 and 132 by adhesive fillets 134 and 136. The
flat contact surfaces of flexure 128 and flat surface 126 at the
top of the slider are also bonded together by adhesive. By using a
flat surface slider, the slider requires less machining, thus
realizing a savings in time and labor costs as well as a reduction
in possible breakage and error during production.
By virtue of this invention, a single integral piece is formed with
a load beam and flexure, thereby realizing a significant savings in
material and labor. Alignment of the load beam and flexure and
welding of the separate parts are eliminated. Certain critical
tolerances that were required in former load beam/flexure
assemblies are no longer needed thereby enhancing the assembly
process. The design allows the separation of the load transfer
function from the gimbaling action which eliminates the weak
bending characteristic found with prior art suspensions. It should
be understood that the parameters, dimensions and materials, among
other things, may be modified within the scope of the invention.
For example, the slider design with the step and platform
configuration disclosed herein can be used with a "50" nanoslider
suspension or other size suspensions.
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