Dynamic magnetic information storage or retrieval – Head mounting – For moving head into/out of transducing position
Reexamination Certificate
2001-10-10
2004-02-10
Nguyen, Hoa T. (Department: 2652)
Dynamic magnetic information storage or retrieval
Head mounting
For moving head into/out of transducing position
Reexamination Certificate
active
06690548
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a ramp mechanism for holding a suspension arm which holds a head for reading and writing of information from and to an information recording disk rotating at a high speed in an information recording disk apparatus in such a state as spaced from the disk when the disk is in its inoperable mode.
Among information recording apparatuses for use with an information processing apparatus such as a computer, a hard disk drive unit as an information recording disk apparatus, which uses a magnetic recording disk rotating at a high speed as a recording medium, rotates a plurality of magnetic recording disks (which will be referred merely to as recording disks, hereinafter) at a high speed, writes or reads information to or from each recording disk by means of magnetic heads provided as associated with upper and lower surfaces of each disk.
The magnetic head for use with the hard disk drive apparatus, which is supported to a suspension arm or the like driven by an actuator, moves on the recording disk at a high speed. Further, the magnetic head and recording disk are not contacted with each other, and the action of an airflow generated by rotation of the recording disk causes the magnetic head to float the recording disk over with a very small gap therebetween.
When the recording disk is not rotated with respect to the magnetic head, it is required for the magnetic head not to be brought into contact with the recording disk. This is because a long-time contact of the magnetic head with the recording disk not being rotated may undesirably result in the fact that the head to stick to the surface of the disk. In such a case, start of the rotation of the recording disk causes the head-stuck surface of the disk to peel off, thus resulting in a damage of the surface of the disk.
Even when the surface contact time between the magnetic head and recording disk is too short to cause such a sticking phenomenon as mentioned above, it is required that the head not be contacted with the disk. This is for the purpose of avoid such a situation as will be explained below. That is, for example, after the magnetic head came into contact with the recording disk being stopped in rotation, if the disk starts its rotation and reaches to a predetermined rotational speed, then a contact friction between the head and disk during that contact period may cause the surface of the disk to be scraped. In order that the magnetic head flies over the surface of the recording disk, it is generally required that the disk reach a predetermined rotational speed.
As mentioned above, so long as the recording disk does not reach the predetermined rotational speed, the head must be spaced from the disk. To realize this, there has been known in these years a mechanism for holding a magnetic head called a ramp which holds a magnetic head and a suspension arm relative to a recording disk with a gap spaced therefrom when the rotational speed of the recording disk is below the predetermined level.
In a recent hard disk drive apparatus, there is provided a ramp as a magnetic-head retraction location where the head is held as spaced from a recording disk when the disk stops its rotation or while it is rotating at a low speed. In such a hard disk drive apparatus, when the rotational speed of the recording disk is decreased to such a level that the head cannot float the disk over, the apparatus unloads the head; whereas, when the rotational speed is increased to such a level as to enough to float the head over, the apparatus loads the head onto the disk. Such a system of unloading and loading the head to and from the ramp as mentioned above is known as a ramp loading system.
The ramp is made of polymeric material, molded and manufactured. The ramp is fixed to a housing of the hard disk apparatus by means of screw, and is subjected to a stress in a compression direction when the ramp is pushed against the housing by a tightening torque of the screw. Accordingly after passage of a long period of time, the ramp made of the polymeric material is susceptible to a creep deformation as a plastic deformation.
Further, for the purpose of rotating the recording disk at a high speed, a motor, a driver circuit therefor, and so on are built in the information recording disk apparatus. Heat evolution of the motor, driver circuits, etc. will cause the internal temperature of the disk apparatus to inevitably increase. Thus even the ambient temperature of the ramp increases during the high-speed rotation of the disk, and decreases therefrom during rotation stoppage of the disk and approaches normal temperature. In other words, the ramp is used in a environment of temperature cycling. In this case, the creep deformation takes place more easily with time passage, as will be clear from the fact that, in a reliability test field for example, time is accelerated with temperature cycle.
FIG.
11
(
a
) is a perspective view of a conventional ramp when all parts of the ramp are made of polymeric material containing polytetrafluoroethylene (PTFE) and are integrally molded. FIG.
11
(
b
) is a enlarged perspective view of a front end edge part of a guide section for guiding a suspension arm in the ramp of FIG.
11
(
a
). In FIGS.
11
(
a
) and
11
(
b
), the ramp is of a type wherein the suspension arms are held when three stages of recording disks for both side use are stacked.
As shown in FIG.
11
(
a
), a conventional ramp
20
includes a mount
21
having a screw pit
25
therein for fixing of the ramp
20
to a housing of an information recording disk apparatus with a screw, and also includes an arm holder
22
. The arm holder
22
has accommodation zones
27
in which a slider having a magnetic head mounted thereto for writing or reading to or from a recording disk is held as spaced from the associated one of the recording disks, and also has guiding parts
28
for facilitating access of the suspension arm to the accommodation zones
27
by sliding associated lifting projection.
The mount
21
and arm holder
22
are integrally molded by once injection molding operation with use of polymeric material containing the PTFE. A metal sleeve
30
, which is inserted into the screw pit
25
and then molded, acts to less transmit a stress accumulated in the vicinity of the screw pit
25
at the time of tightening the screw to the polymeric material part.
The mount
21
is made up of the screw pit
25
, the metal sleeve
30
, and a bracket
23
provided therearound.
The arm holder
22
is supported by the accommodation zones
27
for storage of the lifting projections of the suspension arm associated with upper and lower surfaces of each recording disk, the guiding parts
28
, and a support
24
so that the accommodation zones
27
and guiding parts
28
are aligned in a disk stacking direction.
The accommodation zones
27
and guiding parts
28
are provided not only at upper surface sides shown in FIG.
11
(
a
) but also even at lower sides of horizontally-symmetrical surfaces of each disk. A part of a peripheral edge of each disk is entered into associated one of openings
26
. In other words, a front end edge
29
of each guiding part
28
and each disk within the openings
26
have a positional relationship that the edge and disk are located within the opening in a non-contact condition. The ramp
20
is fixed to the housing by means of a screw so as to satisfy the above positional relationship. As an actuator assembly is rotated in a direction away from the recording disk, the lifting projection mounted to the suspension arm is raised in the vicinity of the front end edge
29
of the associated guiding part
28
, so that the arm is slid along the guiding parts
28
and stored into the associated accommodation zone
27
. Further, as the actuator assembly is rotated in a direction opposed to the above direction, the lifting projection comes out of the accommodation zone
27
, slides along the guiding part
28
, and then released from the front end edge
29
of the guiding part
28
onto the disk.
In the
Ishikawa Tetsuo
Kobayashi Yuhji
Koyanagi Ichiroh
Wu Tsai-Wei
Akin Gump Strauss Hauer & Feld, LLP.
Nguyen Hoa T.
Watko Julie Anne
LandOfFree
Ramp for use in information recording disk apparatus, and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ramp for use in information recording disk apparatus, and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ramp for use in information recording disk apparatus, and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3329314