U.S. patent application number 10/810145 was filed with the patent office on 2004-09-16 for magnetic head device and recording/reproducing apparatus.
This patent application is currently assigned to Maisushita Electric Industrial Co., Ltd.. Invention is credited to Enshu, Hisayuki, Mizuno, Osamu, Murakami, Yutaka.
Application Number | 20040179434 10/810145 |
Document ID | / |
Family ID | 27292969 |
Filed Date | 2004-09-16 |
United States Patent
Application |
20040179434 |
Kind Code |
A1 |
Murakami, Yutaka ; et
al. |
September 16, 2004 |
Magnetic head device and recording/reproducing apparatus
Abstract
A head main body (12) is supported at a free end of a
cantilevered suspension (14). The head main body (12) has a first
holding portion (5) that is substantially in parallel to an
information recording medium (1), and the suspension (14) has a
second holding portion (6) that is substantially in parallel to the
information recording medium (1) and is located near the free end
of the suspension (14). When a magnetic head device is not used,
the head main body (12) is spaced away from the information
recording medium (1). At this time, when an external shock is
applied, the first holding portion (5) and the second holding
portion (6) contact each other, thereby preventing a permanent
deformation of the suspension (14). It is possible to reduce a
displacement amount against a shock when the head main body (12) is
spaced away from the information recording medium (1).
Consequently, a spacing amount of the magnetic head main body (12)
can be reduced. As a result, it becomes possible to make a thinner
optomagnetic recording/reproducing apparatus.
Inventors: |
Murakami, Yutaka;
(Hirakata-shi, JP) ; Mizuno, Osamu; (Osaka-shi,
JP) ; Enshu, Hisayuki; (Jouyou-shi, JP) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Maisushita Electric Industrial Co.,
Ltd.
Kadoma-shi
JP
|
Family ID: |
27292969 |
Appl. No.: |
10/810145 |
Filed: |
March 26, 2004 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10810145 |
Mar 26, 2004 |
|
|
|
09673919 |
Oct 23, 2000 |
|
|
|
09673919 |
Oct 23, 2000 |
|
|
|
PCT/JP00/00986 |
Feb 21, 2000 |
|
|
|
Current U.S.
Class: |
369/13.2 ;
G9B/11.032; G9B/11.036; G9B/21.027; G9B/5.181; G9B/5.193;
G9B/5.198; G9B/5.216 |
Current CPC
Class: |
G11B 5/54 20130101; G11B
11/1055 20130101; G11B 5/5552 20130101; G11B 11/10558 20130101;
G11B 11/1058 20130101; G11B 5/5582 20130101; G11B 21/22 20130101;
G11B 5/596 20130101 |
Class at
Publication: |
369/013.2 |
International
Class: |
G11B 011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 25, 1999 |
JP |
11-047410 |
Mar 26, 1999 |
JP |
11-083313 |
Dec 17, 1999 |
JP |
11-359724 |
Claims
1. A magnetic head device comprising: a suspension that is
cantilevered and provided with an elastic portion; and a head main
body that glides in contact over or floats while keeping a
substantially constant distance from an information recording
medium, and is supported at a free end of the suspension; wherein a
first holding portion protruding substantially in parallel to a
recording surface of the information recording medium is provided
on the head main body, a second holding portion protruding
substantially in parallel to the recording surface of the
information recording medium is provided near the free end of the
suspension, and the first holding portion and the second holding
portion are able to contact each other when the head main body is
displaced in at least one direction because of an elastic
deformation of the suspension.
2. The magnetic head device according to claim 1, wherein the
second holding portion is provided closer to the information
recording medium than the first holding portion is.
3. The magnetic head device according to claim 1, wherein a
plurality of ones selected from the first holding portion and the
second holding portion are placed sequentially in a direction
substantially perpendicular to the recording surface of the
information recording medium, and the other is placed
therebetween.
4. The magnetic head according to claim 1, wherein the first
holding portion and the second holding portion both have a flat
plate shape.
5. The magnetic head device according to claim 1, wherein one of
the first holding portion and the second holding portion has a
convex portion, the other has a through hole, and the convex
portion is inserted in the through hole when the head main body is
displaced in at least one direction.
6. The magnetic head device according to claim 1, wherein one of
the first holding portion and the second holding portion has a
through hole, the other has a first convex portion that passes
through the through hole with clearance and a second convex portion
that is formed at a front end of the first convex portion, and the
second convex portion contacts the one holding portion when the
head main body is displaced in at least one direction.
7. The magnetic head device according to claim 1, wherein the
second holding portion is made of a same material as the suspension
and formed integrally with the suspension.
8. The magnetic head device according to claim 1, wherein the
suspension comprises; a first elastic portion that is supported by
a fastened end, an intermediary portion that is supported by the
first elastic portion and has a rigid body portion made of resin,
and a second elastic portion that is supported by the intermediary
portion, wherein the second holding portion and the rigid body
portion are formed in one piece by molding resin.
9. The magnetic head device according to claim 1, wherein the
second holding portion is made of resin and integrated with the
suspension.
10. The magnetic head device according to claim 1, wherein the
first holding portion and the magnetic head main body are formed in
one piece.
11. A magnetic head device comprising: a fastening member having a
cantilevered arm portion; a head main body for applying a magnetic
field to an information recording medium; and a suspension that is
cantilevered by the fastening member, provided with a supporting
portion for connecting and supporting the head main body on a side
of a free end and has an elastic portion; wherein the arm portion
comprises a contacting portion, and the contacting portion contacts
the elastic portion so that the elastic portion is deformed
elastically when the head main body is located away from the
information recording medium.
12. A magnetic head device comprising: a fastening member having a
cantilevered arm portion; a head main body for applying a magnetic
field to an information recording medium; and a suspension that is
cantilevered by the fastening member, provided with a supporting
portion for connecting and supporting the head main body on a side
of a free end and has a first elastic portion on a side of a
fastened end and a second elastic portion on a side of the free
end; wherein the arm portion comprises a first contacting portion,
and the first contacting portion contacts the first elastic portion
so that the first elastic portion is deformed elastically when the
head main body is located away from the information recording
medium.
13. The magnetic head device according to claim 12, wherein the arm
portion further comprises a second contacting portion, and the
second contacting portion contacts the second elastic portion or
the head main body so that the second elastic portion is deformed
elastically when the head main body is located away from the
information recording medium.
14. The magnetic head device according to claim 13, wherein the
second contacting portion contacts the second elastic portion or
the head main body on the side of the free end of the suspension
with respect to the supporting portion when the head main body is
located away from the information recording medium.
15. The magnetic head device according to any of claims 11 to 13,
wherein the head main body does not protrude beyond the fastening
member on an opposite side of the information recording medium when
the head main body is located away from the information recording
medium.
16. The magnetic head device according to claim 13, wherein the arm
portion further comprises a third contacting portion, and the third
contacting portion contacts the head main body on the side of the
fastened end of the suspension with respect to the supporting
portion when the head main body is located away from the
information recording medium.
17. The magnetic head device according to claim 13 or 16, wherein
the head main body comprises a magnetic pole core, and a surface of
the magnetic pole core opposing a recording surface of the
information recording medium is substantially parallel to the
recording surface when the head main body is located away from the
information recording medium.
18. A recording/reproducing apparatus comprising: a converter for
recording information on and/or reproducing information from an
information recording medium; a suspension system for keeping the
converter at a desired distance and orientation with respect to the
information recording medium; a suspension system supporting member
for supporting the suspension system; and a fixed structure that is
not displaced substantially with respect to an outer case; wherein
the fixed structure is arranged substantially in opposition to the
information recording medium, and at least a part of the suspension
system supporting member is arranged between the fixed structure
and the information recording medium; and the part of the
suspension system supporting member contacts the fixed structure
when the converter is spaced away from the information recording
medium.
19. A recording/reproducing apparatus comprising: a converter for
recording information on and/or reproducing information from an
information recording medium; a suspension system for keeping the
converter at a desired distance and orientation with respect to the
information recording medium; and a suspension system supporting
member for supporting the suspension system; wherein a plurality of
contacting regions are formed integrally with the converter so as
to be substantially rigid; and the contacting regions of the
converter contact the suspension system supporting member when the
converter is spaced away from the information recording medium.
20. A recording/reproducing apparatus comprising: a converter for
recording information on and/or reproducing information from an
information recording medium; a suspension system for keeping the
converter at a desired distance and orientation with respect to the
information recording medium; a suspension system supporting member
for supporting the suspension system; and a fixed structure that is
not displaced substantially with respect to an outer case; wherein
the fixed structure is arranged substantially in opposition to the
information recording medium, and at least a part of the suspension
system supporting member is arranged between the fixed structure
and the information recording medium; a plurality of contacting
regions are formed integrally with the converter so as to be
substantially rigid; and the part of the suspension system
supporting member contacts the fixed structure and the contacting
regions of the converter contact the suspension system supporting
member when the converter is spaced away from the information
recording medium.
21. The recording/reproducing apparatus according to claim 19 or
20, wherein a surface of the converter opposing the information
recording medium is substantially in parallel to the information
recording meidum when the converter is spaced away from the
information recording medium so that the contacting regions contact
the suspension system supporting member.
22. The recording/reproducing apparatus according to claim 18 or
20, wherein a contacting portion of the suspension system
supporting member that contacts the fixed structure is formed to
have a convex surface.
23. The recording/reproducing apparatus according to claim 18 or
20, wherein a region of the fixed structure that contacts the
suspension system supporting member is formed to have a convex
surface.
24. The recording/reproducing apparatus according to claim 23,
wherein a contacting portion of the suspension system supporting
member that contacts the fixed structure is formed to have a
substantially cylindrical surface, and a generating line of the
substantially cylindrical surface is substantially in parallel to
the information recording medium and substantially in perpendicular
to a longitudinal direction of the convex surface formed on the
fixed structure.
25. The recording/reproducing apparatus according to claim 18 or
20, wherein the suspension system supporting member and the fixed
structure are substantially in point contact with each other.
26. The recording/reproducing apparatus according to claim 18 or
20, comprising a vibration absorbing mechanism for damping an
external vibration, wherein the fixed structure is held on a
structure that is supported by the vibration absorbing mechanism.
Description
TECHNICAL FIELD
[0001] [The Invention I]
[0002] The present invention I relates to a magnetic head device
for applying a magnetic field to an information recording medium in
a recording/reproducing apparatus for optomagnetic disks such as
mini disks (referred to as "MD"s in the following) or optomagnetic
data filing systems.
[0003] [The Invention II]
[0004] The present invention II relates to a magnetic head device
for applying a magnetic field to an information recording medium in
a recording/reproducing apparatus for optomagnetic disks such as
mini disks (referred to as "MD"s in the following) or optomagnetic
data filing systems.
[0005] [The Invention III]
[0006] The present invention III relates to a structure of a
recording/reproducing apparatus for recording information on an
information recording medium or reproducing information recorded
thereon by interactions mainly with the information recording
medium, more specifically effects such as optical, thermal and
magnetic field effects. In particular, the present invention III
relates to a structure for loading/unloading a converter for
performing the interactions with the information recording medium
(for example, a magnetic head main body).
BACKGROUND ART
[0007] [The Invention I]
[0008] In a conventional optomagnetic recording/reproducing
apparatus, an optical head device that emits a light beam for
irradiating an optomagnetic recording layer opposes one side of an
optomagnetic disk, which serves as an information recording medium,
that is rotated by a driving mechanism. A magnetic head device that
applies an external magnetic field to the optomagnetic recording
layer opposes the other side of the optomagnetic disk.
[0009] The optomagnetic recording/reproducing apparatus applies a
magnetic field to the optomagnetic recording layer of the rotating
optomagnetic disk by letting the magnetic head device modulate the
direction of the magnetic field in accordance with the information
signal to be recorded, while a light beam from the optical head
device is focused and irradiated on the optomagnetic recording
layer.
[0010] This light beam irradiation heats a portion of the
optomagnetic recording layer to a temperature above the curie
temperature, so that this portion loses its coercive force. After
this portion has been magnetized in the direction of the magnetic
field applied by the magnetic head device, the optomagnetic disk is
moved by rotation relative to the light beam, so that this portion
is cooled below the curie temperature and the magnetization
direction is fixed. Thus, an information signal is recorded in the
optomagnetic recording layer.
[0011] Since there is a possibility that the rotation causes
surface vibration of the optomagnetic disk, an optomagnetic
recording/reproducing apparatus provided with a sliding magnetic
head device that records an information signal while sliding a
magnetic head main body of the magnetic head device (hereinafter,
simply referred to as a "head main body" in the invention I) is
used, for example, for the MDs.
[0012] However, with respect to a resilient force that forces the
head main body against the optomagnetic disk, a force is sufficient
if it causes the head main body to glide on the optomagnetic disk
with a constant sliding pressure and without separating too much
from the main surface of the optomagnetic disk that is rotated.
When the resilient force is too large, the sliding friction between
the head main body and the optomagnetic disk increases, and may
result in considerable wear of the head main body and the
optomagnetic disk.
[0013] Therefore, a suspension for applying the resilient force to
the head main body is formed as a plate spring of thin phosphor
bronze, BeCu or SUS304 or the like, which do not have too much
elasticity and mechanical strength. The head main body is supported
on the side of the free end of such a cantilevered suspension.
[0014] When a shock is applied to the magnetic head device as
described above, the load on the head main body can surpass the
elastic limit of the suspension, so that the suspension is deformed
easily. Accordingly, it becomes necessary to provide a stopper for
restricting the displacement of the head main body so as not to
surpass the elastic deformation limit of the suspension.
[0015] JP 6-60585 A suggests an example of such a magnetic head
device having the stopper.
[0016] The following is a description of the conventional magnetic
head device, with reference to FIGS. 23 to 27.
[0017] FIG. 23 is a plan view of an example of the conventional
magnetic head device. FIG. 24 is a side view of the magnetic head
device shown in FIG. 23 in use. FIG. 25 is a side view of the
magnetic head device shown in FIG. 23 not in use. FIG. 26 is a
perspective view of a head main body of the magnetic head device
shown in FIG. 23. FIG. 27 is an exploded perspective view of the
head main body of the magnetic head device shown in FIG. 23.
[0018] The conventional magnetic head device includes a head main
body 12, a suspension 14 formed as a thin plate spring for pressing
a sliding portion 13 of the head main body 12 against the surface
of an optomagnetic disk 1, and a fastening member 15 to which one
end of the suspension 14 is attached. The head main body 12 is
attached to a gimbal 16 on the side of the free end of the
suspension 14, while the other end of the suspension 14 is attached
to the fastening member 15.
[0019] The head main body 12 is formed as shown in FIGS. 26 and 27.
That is, a bobbin 19 around which a coil 18 is wound is fixed to a
central magnetic pole core 17a of an E-shaped ferrite magnetic pole
core 17 including the central magnetic pole core 17a and side
magnetic pole cores 17b so as to form a magnetic head element 20.
This magnetic head element 20 is attached integrally to one side of
the sliding portion 13 that glides directly in contact over the
optomagnetic disk 1 and is included in a slider 21 made of resin
with excellent sliding characteristics, for example, polyphenylene
sulfide or liquid crystal polymer, thereby forming the head main
body 12.
[0020] A holding portion 27 having a height h for positional
stabilization is disposed on the upper surface of the slider
21.
[0021] The suspension 14 is formed with a thin plate made of a
material such as SUS304 or BeCu. The suspension 14 has an attaching
portion 31 to be attached to the fastening member 15, a first
elastic portion 32 that is extended from the attaching portion 31
and provided for following surface vibration of the optomagnetic
disk 1 and applying an entire load, an intermediary portion 33 that
is extended from the first elastic portion 32 with being inclined
at a predetermined angle so as not to interfere with a cartridge 2
and formed to be a rigid body by being provided with ribs 37 bent
at a right angle on both sides in the width direction, a second
elastic portion 34 that is extended from the intermediary portion
33 and provided for following the surface shape of the optomagnetic
disk 1, and the gimbal 16 that is disposed at the free end of the
second elastic portion 34. The suspension 14 is configured by
forming these in one piece.
[0022] The fastening member 15 is made of a metal plate of such as
iron or SUS. The fastening member 15 has a supporting portion 43
for fastening the attaching portion 31 of the suspension 14, an arm
portion 45 that is extended like an arm from one side of the
supporting portion 43, and a stopper portion 47 that is provided at
the front end of the arm portion 45 by being bent at a right angle
so as to oppose the supporting portion 43. The fastening member 15
is configured by forming these in one piece.
[0023] When the magnetic head device is used (in recording),
namely, in the condition that the sliding portion 13 is gliding in
contact over the optomagnetic disk 1 as shown in FIG. 24, the head
main body 12 moves freely in the vertical direction according to
the surface vibration of the optomagnetic disk 1. Since the
distance h between the upper surface of the head main body 12 and
the holding portion 27 that is bent at a right angle is at least a
surface vibration tolerance of the optomagnetic disk 1, the head
main body 12 can follow the surface vibration of the optomagnetic
disk 1 sufficiently. The distance h needs to be about 1 mm in MDs,
for example.
[0024] When the magnetic head device is not used (in reproducing),
as shown in FIG. 25, it is necessary to consider preventing the
sliding portion 13 from not only contacting the optomagnetic disk 1
but also interfering with a cartridge used exclusively for
reproducing that is not provided with a hole 2a which the head main
body 12 goes into. Accordingly, in order to prevent the sliding
portion 13 from contacting the cartridge 2, a lifter, which is not
shown in the figure, contacts the portion indicated by an arrow 51,
so that the fastening member 15 is rotated around a rotating joint,
which is not shown in the figure, and lifted away from the
optomagnetic disk 1 (in the direction Z). The stroke is about 3 mm.
The holding portion 27 contacts the stopper portion 47 here,
thereby preventing the head main body 12 from hanging down.
[0025] However, in the structure of the conventional magnetic head
device described above, when the front end of the arm portion 45 is
lifted, the lifted stroke of the arm portion 45 needs to be a
distance necessary for letting the sliding portion 13 get out of
the hole 2a of the cartridge 2 completely. In other words, it is
necessary for the arm portion 45 to be lifted by at least the sum
of the distance between the surface of the optomagnetic disk 1 and
the upper surface of the cartridge 2 and the gap between the upper
surface of the stopper portion 47 and the holding portion 27 in
recording (the condition shown in FIG. 24) (that is, about half of
h). Consequently, there has been a problem in that the optomagnetic
recording/reproducing apparatus cannot be made thinner.
[0026] [The Invention II]
[0027] In a conventional optomagnetic recording/reproducing
apparatus, an optical head device that emits a light beam for
irradiating an optomagnetic recording layer opposes one side of an
optomagnetic disk, which serves as an information recording medium
that is rotated by a driving mechanism. A magnetic head device that
applies an external magnetic field to the optomagnetic recording
layer opposes the other side of the optomagnetic disk.
[0028] The optomagnetic recording/reproducing apparatus applies a
magnetic field to the optomagnetic recording layer of the rotating
optomagnetic disk by letting the magnetic head device modulate the
direction of the magnetic field in accordance with the information
signal to be recorded, while a light beam from the optical head
device is focused and irradiated on the optomagnetic recording
layer.
[0029] This light beam irradiation heats a portion of the
optomagnetic recording layer to a temperature above the curie
temperature, so that this portion loses its coercive force. After
this portion has been magnetized in the direction of the magnetic
field applied by the magnetic head device, the optomagnetic disk is
moved by rotation relative to the light beam, so that this portion
is cooled below the curie temperature and the magnetization
direction is fixed. Thus, an information signal is recorded in the
optomagnetic recording layer.
[0030] Since there is a possibility that the rotation causes
surface vibration of the optomagnetic disk, an optomagnetic
recording/reproducing apparatus provided with a sliding magnetic
head device that records an information signal while sliding a head
main body of the magnetic head device (hereinafter, simply referred
to as a "head main body" in the invention II) is used, for example,
for the MDs.
[0031] The following is a description of the conventional magnetic
head device, with reference to FIGS. 42 to 45.
[0032] FIG. 42 is a plan view of an example of the conventional
magnetic head device. FIG. 43 is a side view of the magnetic head
device shown in FIG. 42 in use. FIG. 44 is a side view of the
magnetic head device shown in FIG. 42 not in use. FIG. 45 is a
sectional side view of a head main body of the magnetic head device
shown in FIG. 42.
[0033] The conventional magnetic head device includes a head main
body 12, a suspension 14 formed as a thin plate spring for pressing
a sliding portion 13 of the head main body 12 against the surface
of an optomagnetic disk 1, and a fastening member 15 to which one
end of the suspension 14 is attached. A joining portion 22 of the
sliding portion 21 of the head main body 12 is joined with a gimbal
16 on the side of the free end of the suspension 14 by gluing or
welding, while the other end of the suspension 14 is attached to
the fastening member 15.
[0034] The head main body 12 is formed as in FIG. 45. That is, a
wound coil 18 is fixed to a central magnetic pole core 17a of an
E-shaped ferrite magnetic pole core 17 including the central
magnetic pole core 17a and side magnetic pole cores 17b so as to
form a magnetic head element 20. This magnetic head element 20 is
attached integrally to one side of the sliding portion 13 that
glides directly in contact over the optomagnetic disk 1 and is
included in a slider 21 made of resin with excellent sliding
characteristics, for example, polyphenylene sulfide or liquid
crystal polymer, thereby forming the head main body 12.
[0035] The suspension 14 is formed with a thin plate made of such
as SUS304 or BeCu. The suspension 14 has an attaching portion 31 to
be attached to the fastening member 15, a first elastic portion 32
that is extended from the attaching portion 31 and provided for
following surface vibration of the optomagnetic disk 1 and applying
an entire load, an intermediary portion 33 that is extended from
the first elastic portion 32 with being inclined at a predetermined
angle so as not to interfere with a cartridge 2 and formed to be a
rigid body by being provided with draw ribs 137 formed on both
sides in the width direction by draw forming, a second elastic
portion 34 that is extended from the intermediary portion 33 and
provided for following the surface shape of the optomagnetic disk
1, and the gimbal 16 that is disposed at the free end of the second
elastic portion 34. The suspension 14 is configured by forming
these in one piece.
[0036] Numeral 30 denotes a flexible printed board. One end thereof
is adhered to the head main body 12, while the other end is adhered
to the attaching portion 31 of the suspension 14. One end of the
flexible printed board 30 is soldered to both ends of a lead wire
of the coil 18, while the other end is connected to a driving
circuit of the magnetic head device, which is not shown in the
figure.
[0037] The fastening member 15 is made of a metal plate of such as
iron or SUS. The fastening member 15 has a supporting portion 43
for fastening the attaching portion 31 of the suspension 14, an arm
portion 45 that is extended like an arm from one side of the
supporting portion 43, and a stopper portion 47 that is provided at
the front end of the arm portion 45 by being bent at a right angle
so as to oppose the supporting portion 43. The fastening member 15
is configured by forming these in one piece.
[0038] When the magnetic head device is used (in recording),
namely, in the condition that the sliding portion 13 is gliding in
contact over the optomagnetic disk 1 as shown in FIG. 43, the
sliding portion 13 follows the surface vibration and change in the
surface shape of the optomagnetic disk 1 so as to glide in contact
thereover constantly, by means of the first elastic portion 32, the
second elastic portion 34 and the gimbal 16 (see FIG. 45).
[0039] When the magnetic head device is not used (in reproducing),
as shown in FIG. 44, it is necessary to consider preventing the
sliding portion 13 from not only contacting the optomagnetic disk 1
but also interfering with a cartridge used exclusively for
reproducing that is not provided with a hole 2a into which the head
main body 12 goes. Accordingly, a lifter 101 lifts the intermediary
portion 33, so that the head main body 12 is spaced away from the
cartridge 2 by a gap H2, thereby preventing the sliding portion 13
from contacting the cartridge 2. The upper surface of the head main
body 12 is in contact with the stopper portion 47 here, thus
preventing the head main body 12 from protruding upward.
[0040] Accompanying the recent popularization of small-size
portable appliances, thinner and thinner devices have been
developed. However, in the structure of the conventional magnetic
head device described above, a part of the intermediary portion 33
protruded upward beyond the arm portion 45 when the magnetic head
device is not used. Accordingly, the thickness H3 of the magnetic
head device not in use (see FIG. 44) was larger than the thickness
H1 of the magnetic head device in use (see FIG. 43). Consequently,
there had been a problem in that the optomagnetic
recording/reproducing apparatus cannot be made thinner.
[0041] [The Invention III]
[0042] One example of conventional recording/reproducing apparatus
is mini disks (referred to as "MD"s in the following). A
prerequisite for MDs is the use of a sliding magnetic head main
body (a slider) for optomagnetic overwriting using a modulated
magnetic field.
[0043] There are a recording disk and a reproducing disk in MDs,
and each of them is contained in a predetermined cartridge. Since
the cartridge for containing the reproducing disk does not have an
access hole for the magnetic head main body of the magnetic head
device, it is necessary that the apparatus be operated while the
magnetic head main body is in an unloading state. Also, in portable
recording appliances, even when the recording disk is used, the
magnetic head main body is usually in the unloading state in
reproducing, in order to reduce the friction work of the sliding
magnetic head main body.
[0044] The following is a description of the loading/unloading
forms of the magnetic head device for MDs in particular, as the
conventional recording/reproducing apparatus.
[0045] FIG. 50(a) is a plan view showing the entire structure of
the conventional magnetic head device for MDs, and FIG. 50(b) is a
sectional view showing a main portion of the conventional
recording/reproducing apparatus for MDs when the recording disk is
installed. A rectangular coordinate system is defined in the
directions shown in the figure. For convenience, the positive side
of the z-axis is called the upper side, the opposite side thereof
is called the lower side, and the length in the direction parallel
to the z-axis is called height.
[0046] A recording disk 301 serving as an information recording
medium having an optomagnetic recording film is contained in a
recording cartridge 302. An access hole 302a for an optical head
for recording/reproducing is provided on the lower side of the
recording cartridge 302, while an access hole 302b for the magnetic
head is provided on the upper side thereof, so that both converters
can interact with the recording disk 301 through these access
holes.
[0047] A magnetic head main body 351 has a magnetic head element
including a magnetic core and a coil therein (not shown in the
figure), and slides on the upper surface of the recording disk 301
in the loading state.
[0048] A suspension 352 as a suspension system is formed by
connecting a second elastic portion 352a including a gimbal, an
intermediary portion 352b, a first elastic portion 352c and an
attaching portion 352d in this order. It is preferable that a
spring material such as stainless material or phosphor bronze is
used as their material.
[0049] The magnetic head main body 351 is connected to the gimbal
of the second elastic portion 352a. An elastic deformation of the
second elastic portion 352a gives the degree of free rotatability
around the x-axis and y-axis to the magnetic head main body 351.
The intermediary portion 352b can be regarded substantially as a
rigid body because a cross-sectional rigidity has been improved by
bending. An elastic restoring force of the first elastic portion
352c presses the magnetic head main body 351 substantially only in
the negative direction of the z-axis.
[0050] A fastening member 353 as a suspension system supporting
member has an arm portion that is extended in the x-axis direction,
and the attaching portion 352d of the suspension 352 is connected
to the root of the arm portion. The fastening member 53 usually is
configured with a stainless plate or the like. A stopper portion
353a is formed at the front end of the arm portion. The stopper
portion 353a restricts the range that the suspension 352 is
deformed by an inertial force of a shock caused by such as a
dropping of the recording/reproducing apparatus, thereby preventing
a plastic deformation of the suspension 352.
[0051] The magnetic head device and an optical head device (not
shown in the figure) for the MD are joined with each other by an
angle member 354. A shaft 355 connects the angle member 354 and the
fastening member 353 in such a manner that the fastening member 353
can rotate freely around the y-axis.
[0052] A coil spring 356 is attached to the shaft 355. The coil
spring 356 gives the fastening member 353 a rotating force in the
direction of an arrow R around the shaft 355 and a pressing force
in the negative direction of the y-axis. A fastening member backing
portion 354a is fastened to the angle member 354. The fastening
member backing portion 354a contacts a protruding portion 353b of
the fastening member 353 that is subjected to the rotating force
given by the coil spring 356, and restricts the rotation of the
fastening member 353.
[0053] The angle member 354 is joined with the optical head device,
which is not shown in the figure, in its lower part. When the
optical head device moves in the y-axis direction, which is the
radial direction of the recording disk 301, the magnetic head main
body 351 is linked with the optical head device so as to move to a
certain position in the radial direction of the recording disk
301.
[0054] A substantially plate-like lifter 357 is disposed so as to
rotate freely around a rotating pin 358. FIG. 50(b) shows the
loading state, and when rotating the lifter 357 clockwise around
the rotating pin 358, a cylindrical contacting portion 357a that is
formed at the front end of the lifter 357 lifts upward the
intermediary portion 352b while contacting its lower surface. This
spaces the magnetic head main body 351 away from the recording disk
301, that is, creates the unloading state. The lifter 357 is
fastened to a so-called cartridge holder (not shown in the figure)
or the like that holds the recording cartridge 302 in a freely
rotatable manner via the rotating pin 358, and driven rotatably by
a driving means or the like, which is not shown in the figure.
[0055] The elements described above are installed in an outer case
359 of the recording/reproducing apparatus. Metal such as aluminum
or magnesium usually is used as the material of the outer case 359
so as to make the outer case 359 thinner.
[0056] When a modulation current is passed through the coil
installed in the magnetic head main body 351 in the state of FIG.
50(b) (the loading state), a modulated magnetic field is applied to
the recording disk 301. While rotating the recording disk 301, a
laser beam heats the recording film of the recording disk 301
through the access hole 302a for the optical head, and then the
modulated magnetic field is recorded thereon.
[0057] The magnetic head main body 351 is pressed against and
slides on the recording disk 301 by the elastic restoring force of
the first elastic portion 352c of the suspension 352. Thus, even
when the recording disk 301 is displaced in the z-axis direction
because of the surface vibration, the magnetic head main body 351
maintains its sliding state on the recording disk 301 owing to the
elastic deformation of the first elastic portion 352c.
[0058] In addition, when the surface of the recording disk 301
becomes inclined, the second elastic portion 352a functions so that
the magnetic head main body 351 inclines so as to follow the
surface of the recording disk 301.
[0059] FIG. 51(a) is a sectional view showing a main portion of the
conventional recording/reproducing apparatus for MDs when a
reproducing cartridge 304 is installed. A pre-mastered reproducing
disk 303 is contained in the reproducing cartridge 304, and a
so-called label that shows contents of a contained information is
affixed onto the upper surface of the reproducing cartridge 304. An
access hole 304a for the optical head is provided in the lower side
of the reproducing cartridge 304, while no access hole for the
magnetic head is provided. Thus, the magnetic head main body 351 is
in the unloading state by a function of the lifter 357.
[0060] The lifter 357 lifts the intermediary portion 352b with its
contacting portion 357a so that the first elastic portion 352c is
deformed elastically. Thus, the magnetic head main body 351 is
lifted via the second elastic portion 352a, thereby unload the
magnetic head main body 351. At the same time, the lifter 357 lifts
the fastening member 353 with the contacting portion 357a against
the rotating force of the coil spring 356, thereby spacing the
protruding portion 353b away from the fastening member backing
portion 354a.
[0061] The fastening member 353 is now being spaced away from the
inner surface of the outer case 359 by a distance h1, and the
magnetic head main body 351 is being spaced away from the
reproducing cartridge 304 by a distance h2. These values of
distances h1 and h2 are determined by considering errors and
vibration amplitudes of all elements, and set so as not to be zero
basically, that is, so that the members above do not contact each
other.
[0062] A recording/reproducing apparatus with the configuration
described above is disclosed by, for example, JP 5-128616 A.
[0063] When the fastening member 353 contacts the outer case 359,
large friction and noise are generated because both of them are
usually metal. This hinders the optical head device and the
magnetic head device from moving in the y-axis direction in terms
of an electric power and grade. Also, when the magnetic head main
body 351 glides in contact over the reproducing cartridge 304,
traces of slide and wear are left on a label surface, thereby
deteriorating the grade.
[0064] However, the conventional recording/reproducing apparatus
described above had the following problems.
[0065] When considering the development of small-size devices, the
values of distances h1 and h2 mentioned above are desired to be as
small as possible because they affect the thickness of the
recording/reproducing apparatus directly. However, the conventional
structure described above cannot reduce the values of distances h1
and h2 because of the large variation of the fastening member 353
and the magnetic head main body 351 in the z-axis direction.
[0066] In other words, since the arm tip of the fastening member
353 and the magnetic head main body 351 are located in the farthest
position from the shaft 355 serving as a rotating axis, so-called
the front end, such position amplifies the mechanical error near
the rotating axis. Many factors such as a rotating angle of the
lifter 357 in the unloading position, a relative position of the
contacting portion 357a at the front end of the lifter 357 to the
shaft 355, an error of an deflection curve of the suspension 352
and an error of the angle member 354 are accumulated and also
amplified.
[0067] As a result, positions of the fastening member 353 and the
magnetic head main body 351 in the unloading state vary in the
z-axis direction depending on particular appliances, as shown in a
double-dashed line in the FIG. 51(b). Thus, it was difficult to
reduce the value of the distances h1 and h2 because of its design,
resulting in the larger apparatus. In fact, the designed values of
the distances h1 and h2 are both about 1 to 1.5 mm. In addition,
thinner apparatus were produced by means of improving the
mechanical accuracy, leading to a cost increase.
DISCLOSURE OF INVENTION
[0068] [The Invention I]
[0069] It is an object of the present invention I to solve these
problems of the prior art and to provide a magnetic head device
that maintains a structure with excellent shock resistance and
achieves a thinner optomagnetic recording/reproducing
apparatus.
[0070] In order to achieve the above-described object, the present
invention I has the following structure.
[0071] That is, a magnetic head device of the present invention I
includes a suspension that is cantilevered and provided with an
elastic portion, and a head main body that glides in contact over
or floats keeping a substantially constant distance from an
information recording medium, and is supported at a free end of the
suspension. A first holding portion protruding substantially in
parallel to a recording surface of the information recording medium
is provided on the head main body, a second holding portion
protruding substantially in parallel to the recording surface of
the information recording medium is provided near the free end of
the suspension, and the first holding portion and the second
holding portion are able to contact each other when the head main
body is displaced in at least one direction because of an elastic
deformation of the suspension.
[0072] With the above structure, by providing the first holding
portion to the head main body and the second holding portion to the
suspension, it is possible to reduce the gap between the first and
the second holding portions. Since this reduces the displacement
amount of the head main body due to external shock when the
magnetic head device is not used, it is possible to reduce the
lifting amount when the magnetic head device is not used, thereby
achieving a thinner optomagnetic recording/reproducing
apparatus.
[0073] In the above structure, it is preferable that the second
holding portion is provided closer to the information recording
medium than the first holding portion is. With this preferable
structure, even when a shock giving a downward inertial force is
applied to the magnetic head device not in use, the first and the
second holding portions contact each other, thus preventing a
permanent deformation of the elastic suspension portion.
[0074] Also, in the above structure, it is preferable that a
plurality of ones of the first holding portion and the second
holding portion are placed sequentially in a direction
substantially perpendicular to the recording surface of the
information recording medium, and the other is placed therebetween.
This preferable structure can improve the shock resistance
characteristics in the direction parallel to the recording surface
of the information recording medium.
[0075] Also, in the above structure, it is preferable that the
first holding portion and the second holding portion both have a
flat plate shape. With this preferable structure, the first and the
second holding portions can contact each other more reliably when
the head main body is displaced. Also, it is possible to form or
attach the holding portions easily.
[0076] Also, in the above structure, it is preferable that one of
the first holding portion and the second holding portion has a
convex portion, the other has a through hole, and the convex
portion is inserted in the through hole when the head main body is
displaced in at least one direction. With this preferable
structure, when a shock is applied, the convex portion is inserted
in the through hole so that both holding portions are engaged,
thereby preventing the first holding portion from getting over the
second holding portion. In this manner, still better shock
resistance characteristics can be obtained.
[0077] Also, in the above structure, it is preferable that one of
the first holding portion and the second holding portion has a
through hole, the other has a first convex portion that passes
through the through hole with clearance and a second convex portion
that is formed at a front end of the first convex portion, and the
second convex portion contacts the one holding portion when the
head main body is displaced in at least one direction. With this
preferable structure, the first convex portion constantly is
inserted in the through hole, thereby achieving still better shock
resistance characteristics.
[0078] Also, in the above structure, it is preferable that the
second holding portion is made of a same material as the suspension
and formed integrally with the suspension. With this preferable
structure, a number of components and steps can be reduced, leading
to lower costs.
[0079] Also, in the above structure, it is preferable that the
suspension includes a first elastic portion that is supported by a
fastened end, an intermediary portion that is supported by the
first elastic portion and has a rigid body portion made of resin,
and a second elastic portion that is supported by the intermediary
portion. The second holding portion and the rigid body portion are
formed in one piece by molding resin. With this preferable
structure, it is possible to give rigidity to the intermediary
portion without machining, thereby improving a bending accuracy of
the suspension. Accordingly, it is possible to reduce variation of
pressing load of the head against the information recording medium.
In this manner, the pressing load of the head can be designed to be
small, thus reducing load to the spindle motor, cutting the power
consumption of the optomagnetic recording/reproducing
apparatus.
[0080] Also, in the above structure, the second holding portion may
be made of resin and integrated with the suspension. With this
structure, forming efficiency and accuracy of the second holding
portion can be improved.
[0081] Also, in the above structure, it is preferable that the
first holding portion and the magnetic head main body are formed in
one piece. With this preferable structure, a number of components
and steps can be reduced, lowering cost.
[0082] [The Invention II]
[0083] It is an object of the present invention II to solve these
problems of the prior art and to provide a magnetic head device
that achieves a thinner optomagnetic recording/reproducing
apparatus.
[0084] In order to achieve the above-described object, the present
invention II has the following structure.
[0085] That is, a magnetic head device of a first structure of the
present invention II includes a fastening member having a
cantilevered arm portion, a head main body for applying a magnetic
field to an information recording medium, and a suspension that is
cantilevered by the fastening member, provided with a supporting
portion for connecting and supporting the head main body on a side
of a free end and has an elastic portion. The arm portion includes
a contacting portion, and the contacting portion contacts the
elastic portion so that the elastic portion is deformed elastically
when the head main body is located away from the information
recording medium.
[0086] Also, a magnetic head device of a second structure of the
present invention II includes a fastening member having a
cantilevered arm portion, a head main body for applying a magnetic
field to an information recording medium, and a suspension that is
cantilevered by the fastening member, provided with a supporting
portion for connecting and supporting the head main body on a side
of a free end and has a first elastic portion on a side of a
fastened end and a second elastic portion on a side of the free
end. The arm portion includes a first contacting portion, and the
first contacting portion contacts the first elastic portion so that
the first elastic portion is deformed elastically when the head
main body is located away from the information recording
medium.
[0087] With the above structures, since (the first) elastic portion
is deformed elastically by means of (the first) contacting portion,
the center of rotation at the time of lifting the head main body is
moved from the fastened end of (the first) elastic portion to the
contacting portion with (the first) contacting portion. This makes
the intermediary portion angled nearly horizontally when the head
main body is lifted by a predetermined amount, thereby reducing the
distance that the intermediary portion extends in the direction
perpendicular to the recording surface of the information recording
medium when the magnetic head device is not used. Accordingly, when
the magnetic head device is not used, the intermediary portion does
not protrude beyond the arm portion on the side opposite to the
information recording medium. As a result, the height of the
magnetic head device can be reduced, thereby making a thinner
optomagnetic recording/reproducing apparatus.
[0088] In the above second structure, it is preferable that the arm
portion further includes a second contacting portion, and the
second contacting portion contacts the second elastic portion or
the head main body so that the second elastic portion is deformed
elastically when the head main body is located away from the
information recording medium. With this preferable structure, when
the head main body is located away from the information recording
medium, the head main body can be made substantially parallel to
the recording surface of the information recording medium. Thus, it
is possible to further reduce the height of the magnetic head
device not in use, achieving a still thinner optomagnetic
recording/reproducing apparatus.
[0089] Also, in the above structure, it is preferable that the
second contacting portion contacts the second elastic portion or
the head main body on the side of the free end of the suspension
with respect to the supporting portion when the head main body is
located away from the information recording medium. With this
preferable structure, when the head main body is located away from
the information recording medium, the head main body can be made
substantially parallel to the recording surface of the information
recording medium in a more reliable manner.
[0090] Also, in the above structure, it is preferable that the head
main body does not protrude beyond the fastening member on an
opposite side of the information recording medium when the head
main body is located away from the information recording medium.
With this preferable structure, a still thinner magnetic head
device can be achieved. This can be achieved, for example, in the
following manner. When the head main body is located away from the
information recording medium, it is preferable that the part of the
head main body that is located farthest from the information
recording medium and the part of the second elastic portion or the
head main body that contacts the second contacting portion have a
difference in level, and the difference in level substantially
equals the distance in the perpendicular direction from the part of
the second contacting portion that contacts the second elastic
portion or the head main body to the part of the fastening member
that is located farthest from the information recording medium.
[0091] Also, in the above structure, it is preferable that the arm
portion further includes a third contacting portion, and the third
contacting portion contacts the head main body on the side of the
fastened end of the suspension with respect to the supporting,
portion when the head main body is located away from the
information recording medium. With this preferable structure, when
a shock is applied, the behavior of the head main body away from
the information recording medium can be prevented, thereby
improving shock resistance characteristics.
[0092] Also, in the above structure, it is preferable that the head
main body includes a magnetic pole core, and a surface of the
magnetic pole core opposing a recording surface of the information
recording medium is substantially parallel to the recording surface
when the head main body is located away from the information
recording medium. In other words, it is preferable that, when the
head main body is located away from the information recording
medium, the head main body is in parallel to the recording surface
of the information recording medium, or the length that the head
main body extends in the direction perpendicular to the recording
surface (height) is the smallest. With this preferable structure, a
still thinner magnetic head device can be achieved.
[0093] [The Invention III]
[0094] It is an object of the present invention III to solve these
problems of the prior art and to provide a recording/reproducing
apparatus that can achieve a thinner apparatus with easy and
low-cost means.
[0095] In order to achieve the above-described object, the present
invention III has the following structure.
[0096] A recording/reproducing apparatus in accordance with the
first structure of the present invention III includes a converter
for recording information on and/or reproducing information from an
information recording medium, a suspension system for keeping the
converter at a desired distance and orientation with respect to the
information recording medium, a suspension system supporting member
for supporting the suspension system, and a fixed structure that is
not displaced substantially with respect to an outer case. The
fixed structure is arranged substantially in opposition to the
information recording medium, and at least a part of the suspension
system supporting member is arranged between the fixed structure
and the information recording medium. The part of the suspension
system supporting member contacts the fixed structure when the
converter is spaced away from the information recording medium.
[0097] Also, a recording/reproducing apparatus in accordance with
the second structure of the present invention III includes a
converter for recording information on and/or reproducing
information from an information recording medium, a suspension
system for keeping the converter at a desired distance and
orientation with respect to the information recording medium, and a
suspension system supporting member for supporting the suspension
system. A plurality of contacting regions are formed integrally
with the converter so as to be substantially rigid. The contacting
regions of the converter contact the suspension system supporting
member when the converter is spaced away from the information
recording medium.
[0098] Also, a recording/reproducing apparatus in accordance with
the third structure of the present invention III includes a
converter for recording information on and/or reproducing
information from an information recording medium, a suspension
system for keeping the converter at a desired distance and
orientation with respect to the information recording medium, a
suspension system supporting member for supporting the suspension
system, and a fixed structure that is not displaced substantially
with respect to an outer case. The fixed structure is arranged
substantially in opposition to the information recording medium,
and at least a part of the suspension system supporting member is
arranged between the fixed structure and the information recording
medium. A plurality of contacting regions are formed integrally
with the converter so as to be substantially rigid. The part of the
suspension system supporting member contacts the fixed structure
and, the contacting regions of the converter contact the suspension
system supporting member when the converter is spaced away from the
information recording medium.
[0099] With the first to the third structures described above, it
is possible to provide a recording/reproducing apparatus having
excellent effects as follows. Clearance that was conventionally
necessary for preventing a contact can be reduced, thus achieving a
thinner and smaller recording/reproducing apparatus. At the same
time, since high accuracy mechanism is not necessary, it is
possible to achieve lower cost.
BRIEF DESCRIPTION OF DRAWINGS
[0100] FIG. 1 is a plan view of a magnetic head device of an
embodiment I-1 of the present invention I.
[0101] FIG. 2 is a side view of the magnetic head device of the
embodiment I-1 of the present invention I.
[0102] FIG. 3 is a sectional side view of a main portion of a head
main body of the magnetic head device of the embodiment I-1 of the
present invention I.
[0103] FIG. 4 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-1 of the present invention I.
[0104] FIG. 5 is a side view showing a state of the magnetic head
device of the embodiment I-1 of the present invention I not in
use.
[0105] FIG. 6 is a side view showing a reaction when a shock is
applied to the magnetic head device of the embodiment I-1 of the
present invention I not in use.
[0106] FIG. 7 is a plan view of a magnetic head device of an
embodiment I-2 of the present invention I.
[0107] FIG. 8 is a side view of the magnetic head device of the
embodiment I-2 of the present invention I.
[0108] FIG. 9 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-2 of the present invention I.
[0109] FIG. 10 is a side view showing a reaction when a shock is
applied to the magnetic head device of the embodiment I-2 of the
present invention I not in use.
[0110] FIG. 11 is a plan view of a magnetic head device of an
embodiment I-3 of the present invention I.
[0111] FIG. 12 is a side view of the magnetic head device of the
embodiment I-3 of the present invention I.
[0112] FIG. 13 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-3 of the present invention I.
[0113] FIG. 14 is a plan view of a magnetic head device of an
embodiment I-4 of the present invention I.
[0114] FIG. 15 is a side view of the magnetic head device of the
embodiment I-4 of the present invention I.
[0115] FIG. 16 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-4 of the present invention I.
[0116] FIG. 17 is a plan view of a magnetic head device of an
embodiment I-5 of the present invention I.
[0117] FIG. 18 is a side view of the magnetic head device of the
embodiment I-5 of the present invention I.
[0118] FIG. 19 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-5 of the present invention I.
[0119] FIG. 20 is a plan view of a magnetic head device of an
embodiment I-6 of the present invention I.
[0120] FIG. 21 is a side view of the magnetic head device of the
embodiment I-6 of the present invention I.
[0121] FIG. 22 is an enlarged perspective view of a first holding
portion and a second holding portion of the magnetic head device of
the embodiment I-6 of the present invention I.
[0122] FIG. 23 is a plan view of a conventional magnetic head
device.
[0123] FIG. 24 is a side view of the conventional magnetic head
device in use.
[0124] FIG. 25 is a side view of the conventional magnetic head
device not in use.
[0125] FIG. 26 is a perspective view of a head main body of the
conventional magnetic head device.
[0126] FIG. 27 is an exploded perspective view of the head main
body of the conventional magnetic head device.
[0127] FIG. 28 is a plan view of a magnetic head device of an
embodiment II-1 of the present invention II.
[0128] FIG. 29 is a side view of the magnetic head device of the
embodiment II-1 of the present invention II in use.
[0129] FIG. 30 is a side view of the magnetic head device of the
embodiment II-1 of the present invention II not in use.
[0130] FIG. 31 is a sectional side view of a head main body of the
magnetic head device of the embodiment II-1 of the present
invention II.
[0131] FIG. 32 is a plan view of a suspension of the magnetic head
device of the embodiment II-1 of the present invention II.
[0132] FIG. 33 is a plan view of a fastening member of the magnetic
head device of the embodiment II-1 of the present invention II.
[0133] FIG. 34 is a plan view of a magnetic head device of an
embodiment II-2 of the present invention II.
[0134] FIG. 35 is a side view of the magnetic head device of the
embodiment II-2 of the present invention II in use.
[0135] FIG. 36 is a side view of the magnetic head device of the
embodiment II-2 of the present invention II not in use.
[0136] FIG. 37 is a plan view of a fastening member of the magnetic
head device of the embodiment II-2 of the present invention II.
[0137] FIG. 38 is a plan view of a magnetic head device of an
embodiment II-3 of the present invention II.
[0138] FIG. 39 is a side view of the magnetic head device of the
embodiment II-3 of the present invention II in use.
[0139] FIG. 40 is a side view of the magnetic head device of the
embodiment II-3 of the present invention II not in use.
[0140] FIG. 41 is a plan view of a fastening member of the magnetic
head device of the embodiment II-3 of the present invention II.
[0141] FIG. 42 is a plan view of a conventional magnetic head
device.
[0142] FIG. 43 is a side view of the conventional magnetic head
device in use.
[0143] FIG. 44 is a side view of the conventional magnetic head
device not in use.
[0144] FIG. 45 is a sectional side view of a head main body of the
conventional magnetic head device.
[0145] FIG. 46(a) is a plan view showing an entire structure of a
magnetic head device of an embodiment III-1 of the present
invention III, and FIG. 46(b) is a sectional view showing a main
portion of a recording/reproducing apparatus of the embodiment
III-1 when a reproducing disk is installed.
[0146] FIG. 47 is a sectional view showing a main portion of a
recording/reproducing apparatus of an embodiment III-2 of the
present invention III when a reproducing disk is installed.
[0147] FIG. 48 is a sectional view showing a main portion of a
recording/reproducing apparatus of an embodiment III-3 of the
present invention III when a reproducing disk is installed.
[0148] FIG. 49(a) is a plan view showing an entire structure of a
magnetic head device of an embodiment III-4 of the present
invention III, and FIG. 49(b) is a sectional view showing a main
portion of a recording/reproducing apparatus of the embodiment
III-4 when a reproducing disk is installed.
[0149] FIG. 50(a) is a plan view showing an entire structure of a
conventional magnetic head device, and FIG. 50(b) is a sectional
view showing a main portion of a conventional recording/reproducing
apparatus when a recording disk is installed.
[0150] FIG. 51(a) is a sectional view showing a main portion of a
conventional recording/reproducing apparatus when a reproducing
disk is installed, and FIG. 51(b) is a sectional view for
describing a problem in this apparatus.
BEST MODE FOR CARRYING OUT THE INVENTION
[0151] [The Invention I]
[0152] The following is a description of embodiments of the present
invention I, with reference to accompanying drawings.
[0153] (Embodiment I-1)
[0154] FIG. 1 is a plan view of a magnetic head device of an
embodiment I-1 of the present invention I, FIG. 2 is a side view of
the magnetic head device shown in FIG. 1, FIG. 3 is a sectional
side view of a main portion of a head main body of the magnetic
head device shown in FIG. 1, FIG. 4 is an enlarged perspective view
of a first holding portion and a second holding portion of the
magnetic head device shown in FIG. 1, FIG. 5 is a side view showing
a state of the magnetic head device shown in FIG. 1 not in use, and
FIG. 6 is a side view showing a reaction when a shock is applied to
the magnetic head device not in use.
[0155] The same reference numerals are given to components having
the same functions as in the conventional examples shown in FIGS.
23 to 27, and detailed descriptions thereof are omitted here.
[0156] In FIGS. 1 to 6, numeral 14 denotes a suspension, which is
made of a thin spring material such as SUS304 or BeCu. The
suspension 14 has a planar attaching portion 31 at one end, a first
elastic portion 32 that is extended from one end of the attaching
portion 31, provided with a slit in the center and provided for
following surface vibration of an optomagnetic disk 1 and applying
an entire load, an intermediary portion 33 that is extended from
the first elastic portion 32 while being inclined at a
predetermined angle so as not to interfere with a cartridge 2 and
formed to be a rigid body by being provided with draw ribs 137
formed by draw forming, a second elastic portion 34 that is
extended from the intermediary portion 33 while being inclined at a
predetermined angle with respect to the intermediary portion 33 and
provided for following the surface shape of the optomagnetic disk
1, and a gimbal 16 that is disposed at the free end of the second
elastic portion 34. The suspension 14 is configured by forming
these in one piece.
[0157] Numeral 15 denotes a fastening member made of a metal plate
of such as iron or SUS. The fastening member 15 has a supporting
portion 43 for fastening the attaching portion 31 of the suspension
14, an arm portion 45 that is extended like an arm from one side of
the supporting portion 43, and a stopper portion 147 that is
provided at the front end of the arm portion 45 by being bent at a
right angle so as to oppose the supporting portion 43. The
fastening member 15 is configured by forming these in one
piece.
[0158] Numeral 12 denotes a head main body. A wound coil 18 is
fixed to a central magnetic pole core 17a of an E-shaped ferrite
magnetic pole core 17 including the central magnetic pole core 17a
and side magnetic pole cores 17b so as to form a magnetic head
element 20. This magnetic head element 20 is attached integrally to
a slider 21 made of resin with excellent sliding characteristics,
for example, polyphenylene sulfide or liquid crystal polymer, so
that an open end of the E-shaped magnetic pole core 17 opposes the
optomagnetic disk 1, thereby forming the head main body 12.
[0159] Numeral 13 denotes a sliding portion, which is formed
integrally on a surface of the slider 21 opposing the optomagnetic
disk 1 so as to have a circular arc section, thereby gliding
constantly in point contact over the optomagnetic disk 1 in a
smooth manner.
[0160] Numeral 5 denotes a first holding portion having a flat
plate shape, which is made of SUS, iron or resin such as
polyphenylene sulfide or liquid crystal polymer and fastened to the
upper part of the head main body 12 by glue of epoxy resin or
fusing. The first holding portion 5 also may be provided by being
formed in one piece with the slider 21. By forming them in one
piece, it is possible to reduce components and steps and to lower
costs. Numeral 6 denotes a second holding portion having a flat
plate shape, which is made of SUS, iron or resin such as
polyphenylene sulfide or liquid crystal polymer and fastened close
to a connected end of the second elastic portion 34 to the
intermediary portion 33 (simply referred to as "a connected end" in
the following) by glue of epoxy resin or fusing. The first holding
portion 5 and the second holding portion 6 are both positioned so
as to protrude toward and in opposition to each other substantially
in parallel to the surface of the optomagnetic disk 1.
[0161] The head main body 12 is fastened to the gimbal 16 of the
suspension 14 by fusing or gluing. The attaching portion 31 of the
suspension 14 is fastened to the supporting portion 43 of the
fastening member 15 by laser spot welding.
[0162] When the magnetic head device is used (in recording), the
first holding portion 5 and the second holding portion 6 are
arranged with a gap j therebetween as shown in FIG. 2. The first
elastic portion 32 follows surface vibration of the optomagnetic
disk 1 here. As a result, while the head main body 12 is following
the surface vibration of the optomagnetic disk 1, the first holding
portion 5 and the second holding portion 6 moves in the same phase,
thus hardly changing the gap j. Consequently, it is possible to
reduce the gap j to the amount equal to or smaller than the surface
vibration amount of the optomagnetic disk 1.
[0163] Next, when the magnetic head device is not used, a lifter,
which is not shown in the figure, lifts, for example, the
intermediary portion 33 in the portion indicated by an arrow 51 so
that the head main body 12 does not contact the cartridge 2, as
shown in FIG. 5. Since the fastening member 15 is arranged so as to
be spaced away from the cartridge 2 here, it is unnecessary to lift
the fastening member 15.
[0164] The following is a description of a reaction when a shock is
applied to the magnetic head device, with reference to FIGS. 5 and
6.
[0165] When, for example, the shock is applied to the magnetic head
device not in use shown in FIG. 5, a downward inertial force is
applied to the head main body 12, and the gimbal 16 serves as a
rotation center so that the head main body 12 is displaced
downward, because the center of gravity of the head main body 12 is
located near the magnetic head element 20. Since the first holding
portion 5 is in contact with the second holding portion 6 as shown
in FIG. 6, the displacement of the head main body 12 is restricted
within the elastic deformation range of the gimbal 16 and the
second elastic portion 34. In addition, since the intermediary
portion 33 is in contact with the lifter, which is not shown in the
figure, there is substantially no displacement in the first elastic
portion 32.
[0166] When a similar shock is applied to the magnetic head device
in use, no problem arises because the head main body 12 is in
contact with the optomagnetic disk 1.
[0167] Next, when an upward inertial force due to a shock is
applied to the magnetic head device, a stopper portion 147 and the
head main body 12 contact each other, thereby restricting the
displacement of the head main body 12. Thus, the deformation of the
first elastic portion 32 and the second elastic portion 34 is
controlled within the elastic deformation range.
[0168] As is described above, in accordance with the magnetic head
device of the embodiment I-1 of the present invention I, since the
first holding portion 5 is disposed in the head main body 12 and
the second holding portion 6 is disposed close to the connected end
of the second elastic portion 34 of the suspension, the gap j
between the first holding portion 5 and the second holding portion
6 can be restricted to be equal to or smaller than the surface
vibration amount of the optomagnetic disk 1. Reducing the gap j can
reduce the displacement amount of the head main body 12 due to
shock when the magnetic head device is not used. As a result, it is
possible to reduce the lifting amount when the magnetic head device
is not used, thereby achieving a thinner optomagnetic
recording/reproducing apparatus. At the same time, a permanent
deformation of the gimbal 16 and the second elastic portion 34 can
be prevented with respect to a shock in the vertical direction.
[0169] (Embodiment I-2)
[0170] The following is a description of a magnetic head device in
accordance with the embodiment I-2, with reference to FIGS. 7 to
10.
[0171] FIG. 7 is a plan view of the magnetic head device of the
embodiment I-2 of the present invention I, FIG. 8 is a side view of
the magnetic head device shown in FIG. 7, FIG. 9 is an enlarged
perspective view of first holding portions and a second holding
portion of the magnetic head device shown in FIG. 7, and FIG. 10 is
a side view showing a reaction when a shock is applied to the
magnetic head device not in use.
[0172] The magnetic head device of the embodiment I-2 is different
from that of the embodiment I-1 in that two first holding portions
7 are disposed in a head main body 12, so as to be spaced away from
each other with a predetermined distance in the vertical direction
(the direction perpendicular to the surface of an optomagnetic disk
1), and a second holding portion 6 that is disposed on the side of
the connected end of the second elastic portion 34 is arranged
between the upper and lower first holding portions 7.
[0173] The first holding portions 7 are made of SUS, iron or resin
such as polyphenylene sulfide or liquid crystal polymer, and
fastened to the upper and lower parts of the head main body 12 by
gluing with epoxy resin or welding. The first holding portions 7
also may be provided by being formed in one piece with a slider
21.
[0174] As shown in FIG. 8, the upper first holding portion 7 and
the second holding portion 6 are spaced away from each other by a
gap j, as are the lower first holding portion 7 and the second
holding portion 6. This gap j may be equal to or smaller than the
surface vibration amount of the optomagnetic disk 1, as described
in the embodiment I-1.
[0175] Next, the following is a description of the case where a
shock from sides (in the direction Y) is applied to the magnetic
head device, with reference to FIG. 10.
[0176] As in the embodiment I-1, when the magnetic head device is
not used, a lifter, which is not shown in the figure, lifts the
portion indicated by an arrow 51 so that the head main body 12 does
not contact the cartridge 2. If the shock in the direction Y is
applied here, the head main body 12 attempts to move in the
direction Y. However, since the second elastic portion 34 is wide
in the direction Y, the second elastic portion 34 has a high
rigidity in the direction Y. Therefore, the second elastic portion
34 is displaced in the vertical direction (the direction Z) that
has the lowest rigidity. For example, behaviors are shown such that
the portion near the magnetic head element 20 of the head main body
12 moves upward relative to the second elastic portion 34, and the
portion near the free end of the second elastic portion 34 moves
downward.
[0177] As shown in FIG. 10, the lower first holding portion 7
contacts the second holding portion 6, thereby restricting the
displacement of the head main body 12 with respect to the second
elastic portion 34. Thus, the deformation of the second elastic
portion 34 is controlled within the elastic deformation range.
[0178] When the shock in the vertical direction is applied to the
magnetic head device not in use, the reaction is similar to that
shown in the embodiment I-1, so the description thereof is omitted
here.
[0179] When a similar shock is applied to the magnetic head device
in use, no problem arises because the head main body 12 is in
contact with the optomagnetic disk 1.
[0180] As is described above, in accordance with the magnetic head
device of the embodiment I-2, in addition to the effects of the
embodiment I-1, since the first holding portions 7 are disposed in
the upper and lower parts of the head main body 12 and the second
holding portion 6 is disposed on the side of the connected end of
the second elastic portion 34 so that the second holding portion 6
is arranged between the upper and lower first holding portions 7, a
permanent deformation of the second elastic portion 34 also can be
prevented with respect to a shock in the side direction of the
magnetic head device.
[0181] Instead of the above embodiment, the second holding portion
that is disposed on the side of the connected end of the second
elastic portion 34 may be formed into a substantially U-shape
having upper and lower two holding portions, and only one first
holding portion as in the embodiment I-1 may be disposed in the
head main body 12, so that the first holding portion is arranged
between the upper and lower two holding portions of the second
holding portion.
[0182] (Embodiment I-3)
[0183] The following is a description of a magnetic head device in
accordance with the embodiment I-3, with reference to FIGS. 11 to
13.
[0184] FIG. 11 is a plan view of the magnetic head device of the
embodiment I-3 of the present invention I, FIG. 12 is a side view
of the magnetic head device shown in FIG. 11, and FIG. 13 is an
enlarged perspective view of first holding portions and a second
holding portion of the magnetic head device shown in FIG. 11.
[0185] The magnetic head device of the embodiment I-3 is different
from that of the embodiment I-2 in the following points. That is,
first holding portions 8 are disposed in the upper and lower parts
of a head main body 12, and convex portions 8a protruding toward
the direction perpendicular to a recording surface of an
optomagnetic disk 1 are disposed on the opposing sides of the upper
and lower holding portions 8. On the side of the connected end of
the second elastic portion 34, a second holding portion 9 having a
through hole 9a is disposed between the first holding portions 8.
The through hole 9a is arranged on an extension of the central
lines of the convex portions 8a. Preferably, the convex portions 8a
are inserted in the through hole 9a with clearance.
[0186] The first holding portions 8 and the convex portions 8a are
made of SUS, iron or resin such as polyphenylene sulfide or liquid
crystal polymer, and fastened to the upper and lower parts of the
head main body 12 by glue of epoxy resin or fusing. Also, they may
be provided by being formed in one piece with a slider 21.
[0187] The second holding portion 9 is made of SUS, iron or resin
such as polyphenylene sulfide or liquid crystal polymer, and
fastened close to the connected end of the second elastic portion
34 by gluing with epoxy resin or welding.
[0188] As shown in FIG. 12, the upper first holding portion 8 and
the second holding portion 9 are spaced away from each other by a
gap j, as are the lower first holding portion 8 and the second
holding portion 9. This gap j may be equal to or smaller than the
surface vibration amount of the optomagnetic disk 1, as described
in the embodiment I-1.
[0189] For example, when a shock is applied to the magnetic head
device, causing the reaction similar to that in FIG. 6 or 10, the
convex portions 8a are inserted in the through hole 9a so as to be
engaged. When the shock is large, the sides of the free end of the
first holding portions 8 and the second holding portion 9 may be
deformed elastically in the direction Z. However, by maintaining
the engagement state of the convex portions 8a and the through hole
9a even in such a situation, the present embodiment can prevent the
first holding portions 8 from getting over the second holding
portion 9. Thus, the deformation of the second elastic portion 34
is controlled within the elastic deformation range reliably.
[0190] As is described above, in accordance with the magnetic head
device of the embodiment I-3, the convex portions 8a protruding in
the direction perpendicular to the recording surface of the
optomagnetic disk 1 are disposed respectively on the opposing sides
of the upper and lower first holding portions 8 of the head main
body 12, the second holding portion 9 having the through hole 9a is
disposed on the side of the connected end of the second elastic
portion 34, and the second holding portion 9 is arranged between
the two first holding portions 8 so that the convex portions 8a can
be inserted in the through hole 9a, thus further improving shock
resistance characteristics, in addition to the effects of the
embodiments I-1 and I-2.
[0191] Also, instead of the above embodiment, the second holding
portion on the side of the connected end of the second elastic
portion 34 may be formed into upper and lower two holding portions,
the convex portions protruding toward the direction perpendicular
to the recording surface of the optomagnetic disk 1 may be disposed
on the opposing sides of the second holding portions, and the first
holding portion having a through hole may be provided in the head
main body 12, so that the first holding portion is arranged between
the two second holding portions.
[0192] (Embodiment I-4)
[0193] The following is a description of a magnetic head device in
accordance with the embodiment I-4, with reference to FIGS. 14 to
16.
[0194] FIG. 14 is a plan view of the magnetic head device of the
embodiment I-4 of the present invention I, FIG. 15 is a side view
of the magnetic head device shown in FIG. 14, and FIG. 16 is an
enlarged perspective view of a first holding portion and a second
holding portion of the magnetic head device shown in FIG. 14.
[0195] The magnetic head device of the embodiment I-4 is different
from that of the embodiment I-3 in the following points. That is, a
first holding portion 10 protruding toward the direction parallel
to a recording surface of an optomagnetic disk 1 (in the direction
X) is disposed in the upper part of a head main body 12, and a
first convex portion 10a protruding in the direction perpendicular
to the recording surface of the optomagnetic disk 1 (in the
direction Z) and a second convex portion 10b protruding toward the
direction X from the lower end of the first convex portion 10a are
disposed in this order on the lower surface (the surface on the
side of the optomagnetic disk 1) of the first holding portion 10.
On the side of the connected end of the second elastic portion 34,
a flat plate-shaped second holding portion 11 having a through hole
11a is disposed in the direction substantially parallel to the
recording surface of the optomagnetic disk 1. The first convex
portion 10a passes through the through hole 11a with clearance.
[0196] The first holding portion 10 and the convex portions 10a and
10b are made of SUS, iron or resin such as polyphenylene sulfide or
liquid crystal polymer, and fastened to the upper part of the head
main body 12 by gluing with epoxy resin or welding. Also, they may
be provided by being formed in one piece with a slider 21.
[0197] The second holding portion 11 is made of SUS, iron or resin
such as polyphenylene sulfide or liquid crystal polymer. For
example, the first holding portion 10, the convex portions 10a and
10b are provided in the head main body 12, then the second convex
portion 10b and the first convex portion 10a are inserted in the
through hole 11a of the second holding portion. Subsequently, the
second holding portion 11 is fastened close to the connected end of
the second elastic portion 34 by gluing with epoxy resin or
welding.
[0198] After the assembly, the first holding portion 10 and the
second holding portion 11 can be spaced away from each other by a
gap j, so can the second convex portion 10b and the second holding
portion 11.
[0199] Even if a shock is applied to the magnetic head device,
positional restrictions can be performed. On the one hand,
concerning the displacement in the Z-axis direction, the first
holding portion 10 and the second convex portion 10b contact the
second holding portion 11, thereby restricting the position of the
head main body 12 with respect to the second elastic portion 34. On
the other hand, concerning the displacement in the Y-axis
direction, the first convex portion 10a contacts the inner wall of
the through hole 11a of the second holding portion 11, thereby
restricting the position of the head main body 12 with respect to
the second elastic portion 34. As a result, the deformation of the
second elastic portion 34 is controlled within the elastic
deformation range reliably.
[0200] As is described above, the magnetic head device of the
embodiment I-4 is configured so that the first convex portion 10a
is inserted constantly in the through hole 11a of the second
holding portion 11 and the first holding portion 10 and the convex
portions 10a and 10b contact the second holding portion 11. As a
result, the first holding portion 10 including the convex portions
10a and 10b engages the second holding portion 11 more reliably,
thus further improving shock resistance characteristics, in
addition to the effects of the embodiments I-1 to I-3.
[0201] Instead of the above structure, the first holding portion 10
may be disposed on the lower side (on the side of the optomagnetic
disk 1) of the head main body 12, and the convex portions 10a and
10b may be disposed on the upper surface of the first holding
portion 10.
[0202] Also, a second holding portion having a first convex portion
and a second convex portion that are formed into a L-shape may be
formed on the side of the connected end of the second elastic
portion 34, and a first holding portion having a through hole may
be provided in the head main body 12.
[0203] (Embodiment I-5)
[0204] The following is a description of a magnetic head device in
accordance with the embodiment I-5, with reference to FIGS. 17 to
19.
[0205] FIG. 17 is a plan view of the magnetic head device of the
embodiment I-5 of the present invention I, FIG. 18 is a side view
of the magnetic head device shown in FIG. 17, and FIG. 19 is an
enlarged perspective view of first holding portions and a second
holding portion of the magnetic head device shown in FIG. 17.
[0206] The magnetic head device of the embodiment I-5 is different
from that of the embodiment I-3 in that a second holding portion 23
is formed close to the side of the connected end of the second
elastic portion 34 integrally with and with the same material as a
suspension 14, and a through hole 23a is provided in this second
holding portion 23. First holding portions 8 and convex portions 8a
provided therewith are the same as those in the embodiment I-3.
[0207] When a shock is applied to the magnetic head, the behavior
of the head main body 12 is similar to that in the embodiment I-3,
so the description thereof is omitted here.
[0208] As is described above, in accordance with the magnetic head
device of the embodiment I-5, in addition to the effects of the
embodiments I-1 to I-3, it becomes unnecessary to fasten the second
holding portion as a separate component, thereby reducing
components and steps, leading to lower costs.
[0209] Although the above description used the embodiment I-3 as an
example, the other embodiments also make it possible to form the
second holding portion close to the connected end of the second
elastic portion 34 integrally with and with the same material as
the suspension 14.
[0210] (Embodiment I-6)
[0211] The following is a description of a magnetic head device in
accordance with the embodiment I-6, with reference to FIGS. 20 to
22.
[0212] FIG. 20 is a plan view of the magnetic head device of the
embodiment I-6 of the present invention I, FIG. 21 is a side view
of the magnetic head device shown in FIG. 20, and FIG. 22 is an
enlarged perspective view of first holding portions and a second
holding portion of the magnetic head device shown in FIG. 20.
[0213] The magnetic head device of the embodiment I-6 is different
from that of the embodiment I-5 in that a rigid body portion 25 is
formed in one piece with an intermediary portion 133 of a
suspension 14 by composite molding (insert molding, outsert molding
or the like), and a second holding portion 24 also is formed in one
piece with the rigid body portion 25 by the above-mentioned
composite molding.
[0214] Since the rigid body portion 25 is formed entirely in the
longitudinal direction of the intermediary portion 133 (the
direction Y) by composite molding, it is possible to make the
intermediary portion 133 into a rigid body by keeping it in a flat
plate shape. This eliminates the need for a draw rib 137, thus
improving the accuracy of a bending angle of the suspension 14.
[0215] As is described above, in accordance with the magnetic head
device of the embodiment I-6, since the draw rib 137 is not
necessary, the accuracy of the bending angle of the suspension 14
is improved, thereby further stabilizing a pressing load of the
head main body 12 against the optomagnetic disk 1, in addition to
the effects of the embodiment I-5.
[0216] Accordingly, by reducing a load margin that has been set
considering a variation of the pressing load at the time of
designing, the pressing load of the head main body 12 against the
optomagnetic disk 1 is reduced, thereby lowering a load to a
spindle motor due to the decrease of the sliding friction. As a
result, power consumption of the optomagnetic recording/reproducing
apparatus can be reduced.
[0217] In the above embodiment I-6, the rigid body portion 25 is
provided in the intermediary portion 133 by composite molding, and
the second holding portion 24 also is formed in one piece with the
rigid body portion 25 by the composite molding. However, the
present invention I is not limited to such a structure. For
example, the intermediary portion may be an intermediary portion 33
provided with the draw rib 137 as in the embodiments I-1 to I-5,
and only the second holding portion 24 may be formed in one piece
in a predetermined position of the second elastic portion 34 by
composite molding.
[0218] In the above embodiments I-1 to I-6, the magnetic head
device provided with the head main body gliding in contact over the
information recording medium was discussed as examples. However,
the present invention I is not limited to such magnetic head
devices. For example, the present invention I can be applied to a
magnetic head device in which, by the rotation of the information
recording medium, the head main body floats while maintaining
substantially a constant distance therefrom.
[0219] Also, the information recording medium of the present
invention I includes various kinds of recording media that need a
magnetic head for recording, reproducing or erasing information,
and may be the one adopting, for example, a magnetic recording
system or the like instead of the optomagnetic recording
system.
[0220] [The Invention II]
[0221] The following is a description of embodiments of the present
invention II, with reference to accompanying drawings.
[0222] (Embodiment II-1)
[0223] FIG. 28 is a plan view of a magnetic head device of an
embodiment II-1 of the present invention II, FIG. 29 is a side view
showing a state of the magnetic head device shown in FIG. 28 in
use, FIG. 30 is a side view showing a state of the magnetic head
device shown in FIG. 28 not in use, FIG. 31 is a sectional side
view of a head main body of the magnetic head device shown in FIG.
28, FIG. 32 is a plan view of a suspension of the magnetic head
device shown in FIG. 28, and FIG. 33 is a plan view of a fastening
member of the magnetic head device shown in FIG. 28.
[0224] The same reference numerals are given to components having
the same functions as in the conventional examples shown in FIGS.
42 to 45, and detailed descriptions thereof are omitted here.
[0225] In FIGS. 28 to 33, numeral 14 denotes a suspension, which is
made of a thin spring material such as SUS304 or BeCu. The
suspension 14 has a planar attaching portion 31 at one end, a first
elastic portion 32 that is extended from one end of the attaching
portion 31, provided with a slit in the center and provided for
following surface vibration of an optomagnetic disk 1 and applying
an entire load, an intermediary portion 33 that is extended from
the first elastic portion 32 while being inclined at a
predetermined angle so as not to interfere with a cartridge 2 and
formed to be a rigid body by being provided with draw ribs 137
formed by draw forming, a second elastic portion 34 that is
extended from the intermediary portion 33 while being inclined at a
predetermined angle with respect to the intermediary portion 33 and
provided for following the surface shape of the optomagnetic disk
1, and a gimbal 16 that is disposed at the free end of the second
elastic portion 34. The suspension 14 is configured by forming
these in one piece.
[0226] Numeral 15 denotes a fastening member made of a metal plate
of such as iron or SUS. The fastening member 15 has a supporting
portion 43 for fastening the attaching portion 31 of the suspension
14, an arm portion 45 that is extended like an arm from one side of
the supporting portion 43, a first contacting portion 205
protruding from the arm portion 45 at a right angle so as to oppose
the supporting portion 43 and a stopper portion 147 that is
provided at the front end of the arm portion 45 by being bent at a
right angle so as to oppose the supporting portion 43. The
fastening member 15 is configured by forming these in one piece.
The first contacting portion 205 is located above the first elastic
portion 32, and formed like a step by being bent so as to protrude
from the surface of the arm portion 45 toward the side of the
optomagnetic disk 1.
[0227] Numeral 12 denotes a head main body. A wound coil 18 is
fixed to a central magnetic pole core 17a of an E-shaped ferrite
magnetic pole core 17 including the central magnetic pole core 17a
and side magnetic pole cores 17b so as to form a magnetic head
element 20. This magnetic head element 20 is attached integrally to
a slider 21 made of resin with excellent sliding characteristics,
for example, polyphenylene sulfide or liquid crystal polymer, such
that an open end of the E-shaped magnetic pole core 17 opposes the
optomagnetic disk 1, thereby forming the head main body 12.
[0228] Numeral 13 denotes a sliding portion, which is formed
integrally on a surface of the slider 21 opposing the optomagnetic
disk 1 so as to have a circular arc section, thereby gliding
constantly in point contact over the optomagnetic disk 1 in a
smooth manner.
[0229] Numeral 30 denotes a flexible printed board. One end thereof
is adhered to the head main body 12, while the other end is adhered
to the attaching portion 31 of the suspension 14. One end of the
flexible printed board 30 is soldered to both ends of a lead wire
of the coil 18, while the other end is connected to a driving
circuit of the magnetic head device, which is not shown in the
figure.
[0230] The head main body 12 is fastened by inserting its joining
portion 22 into a supporting hole (supporting portion) 209 of the
suspension 14 and adhering them by welding or gluing. The attaching
portion 31 of the suspension 14 is fastened to the supporting
portion 43 of the fastening member 15 by laser spot welding.
[0231] Numeral 101 denotes a lifter, which is made of, for example,
stainless steel, iron or resin. The lifter 101 rotates around a
rotating joint, which is not shown in the figure, and contacts the
intermediary portion 33 when the magnetic head device is not
used.
[0232] When the magnetic head device is used (in recording), the
first contacting portion 205 and the first elastic portion 32 are
arranged with a gap therebetween as shown in FIG. 29. Also, the
lifter 101 is arranged so as to be spaced away from the magnetic
head device.
[0233] When the magnetic head device is used, the fastening member
15 protrudes the most beyond the upper surface of the cartridge 2.
The thickness of the magnetic head device is defined by a height H1
that is a distance from the upper surface of the cartridge 2 to the
upper surface of the fastening member 15.
[0234] Next, when the magnetic head device is not used, the lifter
101 lifts the intermediary portion 33 such that the head main body
12 does not contact the cartridge 2 by maintaining a gap H2, as
shown in FIG. 30.
[0235] The lifter 101 rotates around the rotating joint, which is
not shown in the figure, and contacts the intermediary portion 33.
At this time, a fastened end (a portion connected to the attaching
portion 31) of the first elastic portion 32 serves as the center of
rotation, so that the head main body 12 is lifted by the lifter
101. When the first elastic portion 32 contacts the first
contacting portion 205, the first elastic portion 32 is deformed
elastically, so that the head main body 12 is rotated around the
contacting portion of the first elastic portion 32 and the first
contacting portion 205 so as to be further lifted. Thus, if the
lifting amount of the head main body 12 equals that in the
conventional example, namely, H2, the intermediary portion 33 is
further rotated. In other words, when the head main body 12 is
lifted to the position that can maintain the gap H2 between the
head main body 12 and the cartridge 2, the angle of inclination of
the intermediary portion 33 becomes close to parallel to the
recording surface of the optomagnetic disk 1. Consequently, the
intermediary portion 33 does not protrude beyond the fastening
member 15 toward the side opposite to the optomagnetic disk 1 (the
upper surface side).
[0236] Since the fastening member 15 is arranged so as to be spaced
away from the cartridge 2 here, it does not have to be lifted by
the lifter 101.
[0237] Also, the upper surface of the head main body 12 contacts a
stopper portion 147 as in the conventional example. This prevents
the head main body 12 from protruding upward beyond the fastening
member 15.
[0238] Thus, the thickness H3 of the magnetic head device not in
use can be made equal to the thickness H1 of the magnetic head
device in use.
[0239] In the present embodiment II-1, the first contacting portion
205 protruded from the arm portion 45 by being bent toward the side
of the optomagnetic disk 1, but it may be formed so as to protrude
partially by draw forming. Also, the first contacting portion 205
may be made of resin and formed by integral molding or gluing.
[0240] In addition, a similar effect can be achieved by forming the
first contacting portion 205 in the same plane as the arm portion
45 and forming a protruding portion made of resin by integral
molding or gluing on the first elastic portion 32 on the side
opposite to the optomagnetic disk 1 in the position to be in
contact with the first contacting portion 205.
[0241] As described above, in accordance with the magnetic head
device of the embodiment II-1 of the present invention II, the
first contacting portion 205 is disposed on the arm portion 45.
When the magnetic head device is not used, the first contacting
portion 205 contacts the first elastic portion 32 so that the first
elastic portion 32 is deformed elastically. Consequently, the
thickness H3 of the magnetic head device not in use can be made
equal to the thickness H1 of the magnetic head device in use,
thereby achieving a thinner optomagnetic recording/reproducing
apparatus.
[0242] (Embodiment II-2)
[0243] The following is a description of a magnetic head device
according to an embodiment II-2, with reference to FIGS. 34 to 37.
FIG. 34 is a plan view of the magnetic head device of the
embodiment II-2 of the present invention II, FIG. 35 is a side view
of the magnetic head device shown in FIG. 34 in use, FIG. 36 is a
side view of the magnetic head device shown in FIG. 34 not in use,
and FIG. 37 is a plan view of a fastening member of the magnetic
head device shown in FIG. 34.
[0244] The magnetic head device of the embodiment II-2 is different
from that of the embodiment II-1 in that, instead of a stopper
portion 147, a second contacting portion 206 is provided in a front
end of an arm portion 45 by being bent at a right angle so as to
oppose a supporting portion 43. The second contacting portion 206
is present on the side of a free end of the suspension 14 with
respect to a joining portion of the suspension 14 with a head main
body 12 (a supporting hole 209 of the suspension 14).
[0245] It is preferable that a convex portion 208 is formed at the
free end of a second elastic portion 34 on the side opposite to an
optomagnetic disk 1 so as to contact the second contacting portion
206. The convex portion 208 can be formed by bending the free end
of the second elastic portion 34 or by draw forming. Also, the
convex portion 208 may be formed by integral molding or gluing of
resin.
[0246] In addition, a protrusion may be provided on the second
contacting portion 206 on the side of the optomagnetic disk 1 by
bending or draw forming. Also, a protrusion may be provided on the
second contacting portion 206 on the side of the optomagnetic disk
1 by integral molding or gluing of resin.
[0247] As shown in FIG. 35, when the magnetic head device is used,
the second contacting portion 206 is arranged so as to be spaced
away from the head main body 12.
[0248] As shown in FIG. 36, when the magnetic head device is not
used, a lifter 101 lifts an intermediary portion 33. At this time,
a first elastic portion 32 contacts a first contacting portion 205
as in the embodiment II-1, while the free end of the second elastic
portion 34 contacts the second contacting portion 206. Accordingly,
the second elastic portion 34 is deformed elastically, so that the
head main body 12 becomes substantially parallel to a recording
surface of the optomagnetic disk 1 (i.e., a surface of a magnetic
pole core 17 opposing the recording surface of the optomagnetic
disk 1 is substantially parallel to the recording surface). In
other words, the distance in the direction perpendicular to the
recording surface (the thickness) of the head main body 12 becomes
substantially minimal. As a result, even when maintaining a gap H2
between a cartridge 2 and the head main body 12, it is possible to
shorten the distance from the cartridge 2 to the upper surface of
the head main body 12 in the direction perpendicular to the
recording surface of the optomagnetic disk 1. Thus, the thicknesses
H1 and H3 of the magnetic head device can be further reduced.
[0249] Also, when the magnetic head device is not used, it is
preferable that the distance between the upper surface of the head
main body 12 and the upper surface of the second elastic portion 34
that is in contact with the second contacting portion 206 in the
normal direction of the recording surface of the optomagnetic disk
1 equals the distance from the surface of the second contacting
portion 206 in contact with the second elastic portion 34 to the
upper surface of a fastening member 15. It is preferable that the
height of the convex portion 208 of the second elastic portion 34
and the protruding amount of the second contacting portion 206 in
the direction of the optomagnetic disk 1 are determined so as to
meet the above condition.
[0250] Such preferable examples can prevent the head main body 12
from protruding beyond the upper surface of the fastening member
15. In addition, the upper surface of the head main body 12
substantially matches the upper surface of the fastening member 15.
As a result, the distance H3 consists only of the thickness of the
head main body 12 and the gap H2 between the cartridge 2 and the
head main body 12, thereby achieving a still thinner magnetic head
device.
[0251] As described above, in accordance with the magnetic head
device of the embodiment II-2, the second contacting portion 206
that is formed in the front end of the arm portion 45 by being bent
at a right angle so as to oppose the supporting portion 43 is
provided on the side of a free end of the suspension 14 with
respect to the joining portion of the suspension 14 with the head
main body 12. Thus, in addition to the effects of the embodiment
II-1, it is possible to make the magnetic head device still
thinner, achieving still thinner optomagnetic recording/reproducing
apparatus.
[0252] In the above examples, when the magnetic head device is not
used, the contacting portion 206 was in contact with the free end
of the second elastic portion 34, but can be in contact with the
head main body 12 (preferably, the front end portion of the head
main body 12) instead. In this case also, it is preferable that the
head main body 12 in contact with the second contacting portion 206
does not protrude upward beyond the fastening member 15 (more
preferably, the upper surfaces of them substantially match) and is
substantially parallel to the optomagnetic disk 1. In order to
achieve this, it is possible that the second contacting portion 206
protrudes on the side of the optomagnetic disk 1, or that a convex
portion with a predetermined height is disposed on the contacting
portion of the head main body 12.
[0253] (Embodiment II-3)
[0254] The following is a description of a magnetic head device
according to an embodiment II-3, with reference to FIGS. 38 to 41.
FIG. 38 is a plan view of the magnetic head device of the
embodiment II-3 of the present invention II, FIG. 39 is a side view
of the magnetic head device shown in FIG. 38 in use, FIG. 40 is a
side view of the magnetic head device shown in FIG. 38 not in use,
and FIG. 41 is a plan view of a fastening member of the magnetic
head device shown in FIG. 38.
[0255] The magnetic head device of the embodiment II-3 is different
from that of the embodiment II-2 in that a third contacting portion
207 is provided in an arm portion 45 so as to oppose a second
contacting portion 206. The third contacting portion 206 is present
on the opposite side of the second contacting portion 206 with
respect to a joining portion of a suspension 14 with a head main
body 12 (a supporting hole 209 of the suspension 14) (between the
supporting hole 209 and a fastened end of the suspension 14).
[0256] It is preferable that a concave portion 210 is provided in
the head main body 12, so that the concave portion 210 contacts the
third contacting portion 207.
[0257] Also, it is preferable that, when the head main body 12 is
placed horizontally with respect to a recording surface of an
optomagnetic disk 1, the distance from the upper surface of the
head main body 12 to the concave portion 210 equals the thickness
of the third contacting portion 207.
[0258] One end of a flexible printed board 30 is adhered to the
concave portion 210, while the other end is adhered to an attaching
portion 31.
[0259] As shown in FIG. 39, when the magnetic head device is used,
the third contacting portion 207 is arranged so as to be spaced
away from the head main body 12.
[0260] As shown in FIG. 40, when the magnetic head device is not
used, a lifter 101 lifts an intermediary portion 33. At this time,
a first elastic portion 32 contacts a first contacting portion 205
and the free end of the second elastic portion 34 contacts the
second contacting portion 206 as in the embodiment II-2, while the
concave portion 210 provided in the head main body 12 contacts the
third contacting portion 207. In this case, the head main body 12
becomes substantially parallel to a recording surface of the
optomagnetic disk 1.
[0261] As shown in FIG. 31, the center of gravity of the head main
body 12 does not match a joining portion 22 because the part in
which a magnetic head element 20 is installed is heavy. Therefore,
when a shock in the direction perpendicular to the optomagnetic
disk 1 is applied to the magnetic head device not in use, the head
main body 12 will be rotated around the joining portion 22 so as to
be inclined. For example, when a shock in the direction away from
the optomagnetic disk 1 is applied, a part of the head main body 12
near the concave portion 210 attempts to rotate in the direction
away from the optomagnetic disk 1. However, the third contacting
portion 207 functions as a stopper so as to prevent the rotation.
As a result, the deformation of the second elastic portion 34 can
be controlled within the elastic deformation range.
[0262] As described above, in accordance with the magnetic head
device of the embodiment II-3, the third contacting portion 207 is
provided with the arm portion 45 on the opposite side of the second
contacting portion 206 with respect to the joining portion of the
head main body 12 with the suspension 14, thereby improving shock
resistance characteristics, in addition to the effects of the
embodiments II-1 and II-2.
[0263] [The Invention III]
[0264] The following is a description of embodiments of the present
invention III, with reference to FIGS. 46 to 49. In every
embodiment, a recording/reproducing apparatus for MDs is used as an
example, and a magnetic head main body is in an unloading state
when a reproducing cartridge is used.
[0265] (Embodiment III-1)
[0266] FIGS. 46(a) and (b) show a recording/reproducing apparatus
in an embodiment III-1 of the present invention III. FIG. 46(a) is
a plan view showing an entire structure of a magnetic head device,
and FIG. 46(b) is a sectional view showing a main portion of the
recording/reproducing apparatus when the reproducing disk is
installed. As in FIGS. 50 and 51 showing a conventional example, a
rectangular coordinate system is defined in the directions shown in
the figure, and the positive side of the z-axis is called the upper
side, the negative side thereof is called the lower side, and the
length in the direction parallel to the z-axis is called the
height.
[0267] A reproducing disk 303 and a reproducing cartridge 304 are
the same as those in the FIG. 51. A magnetic head main body (a
slider) 311, a suspension 312, a fastening member 313, an angle
member 314, a shaft 315, a coil spring 316, a lifter 317 and a
rotating pin 318 correspond to a magnetic head main body 351, a
suspension 352, a fastening member 353, an angle member 354, a
shaft 355, a coil spring 356, a lifter 357 and a rotating pin 358
in the conventional example of FIGS. 50 and 51 including details
shown in subscripts of a, b, c, . . . respectively (for example,
the contacting portion 317a of the lifter 317 corresponds to the
contacting portion 357a of the lifter 357), and basic structures
also are identical. Numeral 319 denotes an outer case as a fixed
structure and corresponds to an outer case 359 in the conventional
example.
[0268] In the present embodiment III-1, a sliding member 370 that
contacts the inner surface of the outer case 319 and functions as a
contacting portion is formed on the upper surface of a stopper
portion 313a of the fastening member 313. The sliding member 370 is
a substantially spherical member, and made of resin material,
preferably, types having sliding characteristics. For example, it
is preferable that the sliding member 370 is made of liquid crystal
polymer or the like in which fluorocarbon materials or appropriate
whiskers are added for improving sliding characteristics.
[0269] The following is a description of the operation in the
embodiment III-1 configured as above.
[0270] The basic operation of the present embodiment III-1 is
similar to that in the conventional example. However, in the
unloading state, the contacting portion 317a of the lifter 317
presses the fastening member 313 upward until the sliding member
370 formed on the upper surface of the stopper portion 313a
contacts the inner surface of the outer case 319, as shown in FIG.
46(b). The lifter 317 lifts the fastening member 313 with a
predetermined force such that the sliding member 370 is held so as
to press the inner surface of the outer case 319 with a
predetermined load.
[0271] As a result, a distance h1 between the inner surface of the
outer case 319 and the fastening member 313 substantially equals
the thickness of the sliding member 370 and does not change.
Therefore, the value of h1 here can be made considerably smaller
than the distance h1 of the conventional example. In the
conventional example, about 1 to 1.5 mm was required for the
distance h1, but, in the present embodiment III-1, about 0.2 mm is
sufficient.
[0272] Also, since there is no change in the position of the
fastening member 313 in the z-axis direction, the positional change
of the lower surface of the magnetic head main body 311 also is
reduced, thereby considerably shortening the distance h2 between
the magnetic head main body 311 and the reproducing cartridge 304.
Thus, it is possible to reduce the dimension of the apparatus in
the part above the reproducing cartridge 304, achieving thinner and
smaller recording/reproducing apparatus.
[0273] In addition, even when there is a mechanical error, the
value of h1 is determined by the thickness of the sliding member
370 after all. Therefore, it is not necessary that the lifter 317,
the angle member 314 and the suspension 312 etc. have high accuracy
equivalent to that in the conventional example. Consequently, it is
possible to lower the cost of the recording/reproducing
apparatus.
[0274] As in the conventional example, the entire magnetic head
device including the magnetic head main body 311 moves in
conjunction with the move of the angle member 314 in the y-axis
direction. In this case, although the sliding member 370 remains in
contact with the inner surface of the outer case 319, the sliding
member 370 does not impose load against the move, nor does it
generate noise because of its excellent sliding characteristics.
Thus, the sliding member 370 can achieve thinner and lower cost
recording/reproducing apparatus without causing any problem.
[0275] The sliding member 370 is attached to the stopper portion
313a of the fastening member 313 easily, and so hardly increases
cost. There are some cases where the sliding member 370 can be made
of the same material as that of the magnetic head main body 311. In
this case, it is also possible to lower cost and increase accuracy
by forming the entire magnetic head device in one piece at the same
time by outsert molding or the like.
[0276] Also, in the present embodiment III-1, the sliding member
370 was substantially spherical, but the present invention III is
not limited to this shape. For example, an elliptic surface or the
like is also possible. However, the spherical surface seems to be
sufficient as long as it causes no problem. In any case, when the
sliding member 370 is substantially in point contact with the inner
surface of the outer case 319, it is possible to stabilize the
contact state and to reduce friction or noise during sliding.
[0277] Furthermore, by arranging a plurality of the sliding members
370 on the stopper portion 313a so as to make two or more points in
contact with the outer case 319, for example, it also may be
possible to stabilize the inclination of the fastening member 313
when contacting the inner surface of the outer case 319. Also, the
sliding member 370 also can be formed as one component that is
provided with many protrusions.
[0278] In addition, similar effects can be achieved by arranging
the sliding member 370 on the part of the fastening member 313
other than the stopper portion 313a.
[0279] (Embodiment III-2)
[0280] FIG. 47 is a sectional view showing a main portion of a
recording/reproducing apparatus in an embodiment III-2 of the
present invention III. A rectangular coordinate system is defined
in the directions shown in the figure, and the positive side of the
z-axis is called the upper side, the negative side thereof is
called the lower side, and the length in the direction parallel to
the z-axis is called the height.
[0281] In FIG. 47, a reproducing disk 303, a reproducing cartridge
304, a magnetic head main body 311, a suspension 312, a fastening
member 313, an angle member 314, a shaft 315, a lifter 317, a
rotating pin 318 and an outer case 319 are the same as those in the
embodiment III-1.
[0282] In the present embodiment III-2, a sliding member 371 is
disposed on the inner surface of the outer case 319. The sliding
member 371 is a substantially cylindrical member having a length
covering a moving amount of the magnetic head main body 311 in a
radial direction, and is disposed in parallel to a moving direction
of the magnetic head main body 311. The sliding member 371 is made
of resin material or the like having sliding characteristics, like
the sliding member 370 in the embodiment III-1. As in the
embodiment III-1, when the magnetic head main body 311 is in an
unloading state, the lifter 317 lifts the fastening member 313. At
this time, the stopper portion 313a of the fastening member 313 is
in contact with the sliding member 371 formed on the inner surface
of the outer case 319. In the present embodiment III-2, therefore,
the stopper portion 313a corresponds to the contacting portion in
the present invention III.
[0283] Wherever in the radial direction of the reproducing disk 303
the magnetic head main body 311 moves, the contacting state does
not change and change in sliding friction is slight in the
unloading state, because the sliding member 371 has a length
covering the moving amount of the magnetic head main body 311.
[0284] In accordance with the present embodiment III-2, it is
possible to achieve thinner and lower-cost recording/reproducing
apparatus as in the embodiment III-1. When the magnetic head device
is too fragile in the step of providing the sliding member 370 with
the magnetic head device as in the embodiment III-1, the present
embodiment III-2 is more appropriate.
[0285] The sliding member 371 was arranged in the position in
contact with the stopper portion 313a in the present embodiment
III-2, but also can be arranged in the position in contact with the
other part of the fastening member 313 or a member connected to the
fastening member 313.
[0286] In addition, a shape maintaining an appropriate contacting
relationship with the sliding member 371 also may be formed on the
upper surface of the stopper portion 313a. For example, a
cylindrical surface having a generating line parallel to the x-axis
is formed integrally on the upper surface of the stopper portion
313a, or a member that is formed in a separate step and has such a
cylindrical surface is attached thereto. Then, it becomes
substantially in point contact with the sliding member 371 formed
to have a cylindrical surface having a generating line parallel to
the y-axis, thereby stabilizing the contact state. In addition, a
shape that is provided with raised portions at the both ends of the
cylindrical surface in the generating line direction may be given
to each of the sliding member 371 and the stopper portion 313a that
are formed to have cylindrical surfaces as above. This is effective
in preventing the sliding member 371 and the stopper portion 313a
from being disengaged from each other.
[0287] In the above example, the sliding member 371 had the
cylindrical surface. However, in the case where, for example, it is
possible to form a contacting portion having a spherical or
elliptic surface as in the embodiment III-1 in a portion on the
upper surface of the fastening member 313, the sliding member 371
also can be formed to have a flat plate shape, namely a tape-like
shape because the sliding member 371 still will be substantially in
point contact with the contacting portion.
[0288] (Embodiment III-3)
[0289] FIG. 48 is a sectional view showing a main portion of a
recording/reproducing apparatus in an embodiment III-3 of the
present invention III. A rectangular coordinate system is defined
in the directions shown in the figure, and the positive side of the
z-axis is called the upper side, the negative side thereof is
called the lower side, and the length in the direction parallel to
the z-axis is called the height.
[0290] In FIG. 48, a reproducing disk 303, a reproducing cartridge
304, a magnetic head main body 311, a suspension 312, a fastening
member 313, an angle member 314, a shaft 315, a lifter 317, a
rotating pin 318 and a sliding member 370 are the same as those in
the embodiment III-1. An outer case 320 functions in the same
manner as an outer case 319 of the embodiment III-1.
[0291] Numeral 321 denotes a cartridge holder, which is a part of a
mechanism holding the reproducing cartridge 304, and only a
plate-like structure above the reproducing cartridge 34 is shown
here. The cartridge holder 321 is provided with an opening 321a for
arranging the magnetic head main body 311 therein, so that a
recording disk also can be mounted into the cartridge holder
321.
[0292] A magnetic head main body cover 322 as a fixed structure
that is formed by bending a plate-like member is fastened to the
upper surface of the cartridge holder 321. A part of the magnetic
head main body cover 322 is located between the outer case 320 and
the fastening member 313, and above the magnetic head main body
311. The magnetic head main body cover 322 has a length in the
y-axis direction that can cover at least a moving range of the
magnetic head device in the y-axis direction.
[0293] The following is a description of the operation in the
embodiment III-3 configured as above.
[0294] As in the embodiment III-1, when the magnetic head main body
311 comes to an unloading state because of the rotating force of
the lifter 317, the sliding member 370 that is arranged on the
upper surface of a stopper portion 313a of the fastening member 313
contacts the lower surface of the magnetic head main body cover
322. Under this state, when the magnetic head main body 311 moves
in a radial direction, the sliding member 370 slides on the lower
surface of the magnetic head main body cover 322. However, the
sliding member 370 does not impose load against the move, nor does
it generate noise, as mentioned in the embodiment III-1.
[0295] In the embodiments III-1 and III-2, since the fastening
member 313 was in direct contact with the inner surface of the
outer case 319 via the sliding member 370 etc., a mechanical
disturbance to the outer case 319 was transmitted to the fastening
member 313 directly. On the other hand, in the present embodiment
III-3, the fastening member 313 and the outer case 320 are not in
direct contact with each other, thus achieving a form more
resistant to the disturbance.
[0296] Although the magnetic head main body cover 322 was connected
to the cartridge holder 321 in the present embodiment III-3, it may
be connected to anywhere as long as it does not contact the outer
case directly. For example, it also may be possible to fasten the
magnetic head main body cover 322 to a so-called chassis (a
structure that supports an optomagnetic head device and a spindle
motor for supporting and rotating a disk).
[0297] In a usual design of equipment that is subjected to an
external vibration, a vibration absorbing mechanism such as a
damper is placed between the outer case and an internal structure
such as a chassis, thereby reducing the mechanical disturbance to
the internal structure. In such apparatus, the magnetic head main
body cover 322 can be fastened to an internal system that is
supported by the vibration absorbing mechanism, thereby achieving a
structure in which the influences of the disturbance are unlikely
to be transmitted to the fastening member 313. It is especially
preferable that the magnetic head main body cover 322 is arranged
where it is possible to maintain the highest accuracy within such a
range.
[0298] (Embodiment III-4)
[0299] FIGS. 49(a) and (b) show a recording/reproducing apparatus
in an embodiment III-4 of the present invention III. FIG. 49(a) is
a plan view showing an entire structure of a magnetic head device,
and FIG. 49(b) is a sectional view showing a main portion of the
recording/reproducing apparatus when the reproducing disk is
installed. A rectangular coordinate system is defined in the
directions shown in the figure, and the positive side of the z-axis
is called the upper side, the negative side thereof is called the
lower side, and the length in the direction parallel to the z-axis
is called the height. FIG. 49(a) shows the state in which a part of
a stopper portion 333a is cut out so that a structure of a magnetic
head main body 331 hidden under the stopper portion 333a can be
indicated.
[0300] In FIGS. 49(a) and (b), a reproducing disk 303, a
reproducing cartridge 304, a suspension 312, an angle member 314, a
shaft 315, a coil spring 316, a lifter 317, a rotating pin 318 and
a sliding member 370 are the same as those in the embodiment III-1.
An outer case 323 functions in the same manner as an outer case 319
of the embodiment III-1.
[0301] A fastening member 333 has substantially the same form
including the stopper portion 333a as that of the fastening member
313 of the embodiment III-1, but is different from the fastening
member 313 of the embodiment III-1 in that a magnetic head main
body contacting portion 333b is formed. The magnetic head main body
contacting portion 333b is formed in the mid-way position of an
arm-like portion of the fastening member 333 so as to protrude in
the y-axis direction.
[0302] The magnetic head main body 331 has substantially the same
function and shape as those of the magnetic head main body 311 of
the embodiment III-1, but is different from the magnetic head main
body 311 of the embodiment III-1 in that the magnetic head main
body 331 here has a first protrusion 331a protruding in a positive
direction of the z-axis near the end portion of a negative
direction of the x-axis and a second protrusion 331b protruding in
a positive direction of the x-axis at the end portion of a positive
direction of the x-axis. These protrusions function as contacting
regions that contact the fastening member 333.
[0303] The upper surfaces of the first protrusion 331a and the
second protrusion 331b are formed in a position lower than the
highest part of the magnetic head main body 331 by the thickness of
the fastening member 333 when the surface of the magnetic head main
body 331 opposing to the disk is placed along the horizontal
direction. When the magnetic head main body 331 is in an unloading
state, the first protrusion 331a and the second protrusion 331b
contact the lower surface of the stopper portion 333a and the lower
surface of the magnetic head main body contacting portion 333b
respectively.
[0304] A sliding tape 372 is attached to the position of the inner
surface of the outer case 323 that contacts the sliding portion 370
when the magnetic head main body is in the unloading state. The
sliding tape 372 is, for example, a belt-like tape that is coated
with fluorocarbon material or the like on its surface, and slides
well on the sliding member 370. The sliding tape 372 has a length
covering a moving amount of the magnetic head main body 331 in a
radial direction, and is arranged parallel to the moving direction
of the magnetic head main body 331.
[0305] The following is a description of the operation in the
embodiment III-4 configured as above.
[0306] As in the embodiment III-1, when the magnetic head device
331 comes to an unloading state because of the rotating force of
the lifter 317, the sliding member 370 that is arranged on the
upper surface of the stopper portion 333a of the fastening member
333 contacts the sliding tape 372 attached to the inner surface of
the outer case 323. Under this state, when the magnetic head main
body 331 moves in the radial direction, the sliding member 370
slides on the sliding tape 372. Therefore, the frictional force
becomes still smaller than that in the embodiment III-1.
[0307] Also, since the sliding tape 372 is very thin, a distance h1
between the fastening member 333 and the inner surface of the outer
case 323 substantially equals that in the embodiment III-1, and can
be shortened considerably compared with the conventional
example.
[0308] In addition, the magnetic head main body 331 is lifted via
the suspension 312 by the rotating force of the lifter 317 in the
unloading state, so that the suspension 312 is deformed
elastically. Then, the upper surfaces of the first protrusion 331a
and the second protrusion 331b of the magnetic head main body 331
are pressed against the lower surfaces of the stopper portion 333a
and the magnetic head main body contacting portion 333b of the
fastening member 333 respectively. Since the upper surfaces of the
first protrusion 331a and the second protrusion 331b are located in
the position lower than the highest part of the magnetic head main
body 331 by the thickness of the fastening member 333, the surface
of the magnetic head main body 331 opposing to the disk 303 is held
substantially parallel to the disk surface. As a result, in the
unloading state, the magnetic head main body 331 is held pressed
against the fastening member 333 in such a way that the thickness
of the magnetic head main body 331 in the z-axis direction measured
from the fastening member 333 is substantially the shortest.
[0309] Accordingly, the distance in the z-axis direction that the
magnetic head main body 331 extends can be made shorter than that
of the conventional example. Also, there is substantially no
positional change of the magnetic head main body 331 in the z-axis
direction, thereby reducing a distance h2 between the reproducing
cartridge 304 and the magnetic head main body 331 considerably.
Specifically, the value of the distance h2 that was about 1 to 1.5
mm conventionally can be made about 0.3 to 0.5 mm.
[0310] In the embodiment III-4, mechanical accuracy is required in
the parts such as the thickness of the sliding member 370, the
thickness of the sliding tape 372, the heights of the first
protrusion 331a and the second protrusion 331b and the thickness of
the fastening member 333. It is very easy to maintain and control
the accuracy of these parts. Consequently, the cost can be lowered
considerably compared with the conventional maintenance and control
of the mechanical accuracy.
[0311] In the present embodiment III-4, a coating can be applied
directly to the outer case 323 instead of providing the sliding
tape 372. Furthermore, by using the magnetic head main body cover
322 described in the embodiment III-3, it is possible to improve
the stability against disturbance.
[0312] Also, the two protrusions 331a and 331b were disposed on the
magnetic head main body 331 as contacting regions with the
fastening member 333. However, for example, three protrusions may
be disposed so that the magnetic head main body 331 can be fastened
to the fastening member 333 in a more stable manner, thereby
further reducing the distance h2.
[0313] In addition, the two protrusions 331a and 331b were disposed
such that the surface of the magnetic head main body 331 opposing
to the disk is substantially in parallel to the reproducing disk
303. However, the protrusions 331a and 331b may be disposed so that
the magnetic head main body 331 in the unloading state is held
inclined with respect to the disk surface, when the stress applied
to the suspension 312 for maintaining the parallel state is too
large. In this case, although the reducing amount of the distance
in the z-axis direction that the magnetic head main body 331
extends and the distance h2 is a little smaller, it is possible to
obtain a certain effect of maintaining the positional stability of
the magnetic head main body 331.
[0314] In the above embodiments III-1 to III-4, MDs were discussed
as an example of recording/reproducing apparatus, but the present
invention III is not limited to those and can be applied to all the
recording/reproducing apparatus that necessitates the operation in
the unloading state of the converter.
[0315] The inventions I to III may be embodied in other specific
forms without departing from the spirit or essential
characteristics thereof. The embodiments disclosed in this
application are to be considered in all respects as illustrative
and not restrictive, the scopes of the inventions I to III being
indicated by the appended claims rather than by the foregoing
description, all changes that come within the meaning and range of
equivalency of the claims are intended to be embraced therein.
* * * * *