1. Field of the Invention
The present invention relates to a storage medium apparatus in which a storage medium for storing data is incorporated, and a method of manufacturing the same.
2. Description of the Related Art
In recent years, there have been rapidly developed, along with development in computer techniques, techniques involving devices incorporated in a computer or peripheral devices connected to a computer from the outside. As one of such techniques, there is known an apparatus such as a magnetic disk that is provided with a planar storage medium and is directed for writing information in the storage medium to store the information.
Some of the apparatuses for storing information using a storage medium make a head section for recording and reproducing information with respect to the storage medium closer to the surface of the storage medium while rotating the storage medium so as to record information into each storage area (track) on the storage medium or to reproduce information from each track. Since a storage medium provided in such an apparatus may be damaged from a member contacting with the storage medium at the time of the rotation of the storage medium, it may be provided at part of the storage medium surface with a protection film in order to avoid such a damage (For example, see Japanese Patent Application Publication No. 61-148686 Publication).
In the field of apparatuses for writing information into a storage medium to store the information, in recent years, there has been increased a demand for apparatuses which are provided with a storage medium having a higher recording density along with rapid development in computer techniques, and there has been increased the recording density of commercially-available storage mediums year after year.
Generally, as the recording density of the storage medium increases, it is required that the distance between the storage medium and the head section is made shorter for precise information recording/reproducing and further that the distance is kept constant at each point on the storage medium. However, when the apparatus is assembled in a state where foreign materials such as dusts are between the storage medium and a fixing member for fixing the storage medium on a rotation shaft, a distortion may occur in the storage medium where foreign materials exist. Since flatness of the storage medium is lost if such a distortion occurs, defect areas where information recording or reproducing is disabled appear near the distortion intensively. The concentration of the defect areas will be described by way of a case where the storage medium is a magnetic disk.
Generally, a magnetic disk is provided with a disk substrate having high intensity and hardness, an under layer for controlling recording characteristics of the magnetic disk and a magnetic layer for recording information are sequentially formed on the substrate and a protection layer for protecting the magnetic layer is further formed on the magnetic layer to serve as the disk surface. The disk substrate is made of a glass substrate having a thickness of 0.8 to 1 mm and the under layer and the magnetic layer are made of an alloy material having a thickness of about 5 to 20 nm. Further, the protection layer is made of a material such as diamond-like carbon (DLC) having a thickness of about 5 to 10 nm. A lubrication layer made of fluorinated lubricant such as perfluoro polyether is formed at a thickness of 1 to 2 nm on the protection layer in order to restrict wear caused by sliding of the head section.
In
The present invention has been made in view of the above circumstances and provides a storage medium apparatus, in which a distortion is prevented from occurring in a storage medium, which is provided with the storage medium such as a drive member for rotating and driving the provided storage medium or a casing in which the rotation drive member provided with the storage medium is accommodated, and a method of manufacturing the same.
The present invention provides a method of manufacturing a storage medium apparatus in which a storage medium which stores data is incorporated according to a first aspect, including the steps of:
disposing the storage medium onto a first unit having an insertion section to be inserted into a through hole of the storage medium and an abutment face made of a soft metal material and spreading around the insertion section, such that the insertion section is inserted into the through hole of the storage medium and the abutment face abuts on a surface of the storage medium;
abutting an abutment face of a second unit on a surface of the storage medium opposite to the surface abutting the abutment face of the first unit, the abutment face of the second unit being made of a soft metal material; and
while holding the storage medium between the first unit and the second unit, fixing the storage medium and at least one of the first unit and the second unit by rotating the storage medium and the one relatively to each other about the through hole.
The “storage medium apparatus” includes not only a finished apparatus which uses a storage medium to perform storage like a magnetic storage apparatus but also a partial apparatus into which the storage medium is incorporated during the step of manufacturing the finished apparatus. This point is applied also in the following.
In the method of manufacturing a storage medium apparatus according to the present invention, the storage medium apparatus is manufactured such that the storage medium is sandwiched to be fixed between the abutment face of the first unit made of a soft metal material and the abutment face of the second unit made of a soft metal material. Thus, even when foreign materials enter between the storage medium and the first unit or between the storage medium and the second unit, the foreign materials dent the soft metal material. Here, since the soft metal is resistant to heat generated when the storage medium apparatus is in an active state and has a small hardness among metals, it is suitable as a material which can be dented by foreign materials. Further, at least one of the first unit and the second unit as well as the storage medium are relatively rotated about the through hole so that the soft metal material can be reliably dented by the foreign materials sandwiched between the storage medium and the soft metal material.
Thus, in the storage medium apparatus manufactured by the method of manufacturing a storage medium apparatus of the present invention, since the storage medium is kept flat even when the foreign materials are present, a distortion hardly occurs in the storage medium, thereby avoiding the concentration of the defect areas.
The present invention also provides a method of manufacturing a storage medium apparatus in which a storage medium which stores data is incorporated according to a second aspect, including:
creating a first abutment face of a first unit, which has an insertion section to be inserted into a though hole of the storage medium and a face opposed to a surface of the storage medium and spreading around the insertion section, by providing a soft metal material at the face of the first unit;
disposing the storage medium onto the insertion section such that the surface of the storage medium abuts on the first abutment face of the first unit;
creating a second abutment face of a second unit, which has a face opposed to a surface of the storage medium opposite to the surface abutting the first abutment face of the first unit, by providing a soft metal material at the face of the second unit; and
fixing the storage medium by abutting the second unit against the surface of the storage medium opposite to the surface abutting the first abutment face of the first unit, and holding the storage medium between the first unit and the second unit.
The storage medium apparatus is manufactured such that the soft metal material suitable for a material of the member which can be dented by foreign materials is provided at the abutment face of the first unit and the abutment face of the second unit so that a distortion hardly occurs, thereby avoiding the concentration of the defect areas.
In the method of manufacturing a storage medium apparatus according to the first aspect of the present invention and the method of manufacturing a storage medium apparatus according to the second aspect of the present invention, it is preferable that “the second unit is either of a penetration type that has a through hole into which the insertion section of the first unit is inserted and is sandwiched between the plural storage mediums while abutting on a surface of each storage medium, and a termination type that is fixed at a tip end of the insertion section of the first unit,
the step of disposing is a step of alternately disposing the storage medium and the second unit of the penetration type onto the first unit, and
the step of fixing is a step of fixing each of the storage mediums by holding the storage medium disposed onto the first unit and the second unit of the penetration type between the first unit and the second unit of the termination type, and clamping the first unit and the second unit of the termination type to each other.”
According to this additional feature, even when manufacturing the storage medium apparatus having plural storage mediums, the storage medium apparatus will be manufactured in which a distortion hardly occurs in each storage medium.
Further, in the method of manufacturing a storage medium apparatus according to the first aspect of the present invention and the method of manufacturing a storage medium apparatus according to the second aspect of the present invention, it is also preferable that “each of the abutment faces of the first unit and the second unit is made of a soft metal material softer than a substrate material forming the storage medium.”
According to this additional feature, since the foreign materials easily dent the soft metal material before a distortion occurs in the storage medium, flatness of the storage medium is kept, and even when the foreign materials are present, they hardly affect information recording/reproducing.
Furthermore, in the method of manufacturing a storage medium apparatus according to the first aspect of the present invention and the method of manufacturing a storage medium apparatus according to the second aspect of the present invention, it is also preferable that “the soft metal material used in the first unit and the second unit has a thickness within a range from 0.02 mm to 1.00 mm in the direction perpendicular to the abutment face.”
The thickness of the abutment face needs to be thicker than a typical size of a foreign material. The height of the storage medium apparatus in the direction perpendicular to the abutment face needs to be restricted to avoid size increase of the storage medium apparatus. When the thickness of the soft metal material ranges between 0.02 mm and 1.00 mm inclusive in the direction perpendicular to the abutment face, such conditions are easily met.
Further, in the method of manufacturing a storage medium apparatus according to the first aspect of the present invention, it is also preferable that “the fixing step is a step where when holding the storage medium between the second unit and the first unit, the storage medium is sandwiched at a pressure of about 0.5 kgf/cm2”.
According to this additional feature, the storage medium can be tightly sandwiched without causing damage to the storage medium.
The present invention also provides a storage medium apparatus in which a storage medium which stores data is incorporated, including:
a first unit which comprises an insertion section inserted into a through hole of the storage medium and an abutment face made of a soft metal material and spreading like a plate around the insertion section while abutting a surface of the storage medium; and
a second unit which comprises an abutment face made of a soft metal material and abutting a surface of the storage medium opposite to the surface abutting the abutment face of the first unit.
The storage medium apparatus according to the present invention employs a soft metal material suitable for a material of the member which can be dented by foreign materials as a material of the abutment face of the first unit and the abutment face of the second unit so that a distortion hardly occurs in the storage medium, thereby preventing the concentration of the defect areas.
According to the present invention, occurrence of a distortion can be prevented.
Hereinafter, an embodiment according to the present invention will be described.
The hard disk drive (HDD) 1 shown in the figures is provided with a disk-shaped magnetic disk 12 having a through hole at its center as shown in
As shown in
The hub 14 can rotate in response to a drive force of a drive motor 13, and the two magnetic disks 12, the clamp 20 and the spacer 21 rotate about the center of the disk-shaped magnetic disk 12 shown in
As shown in
In the HDD 1, information is recorded into the magnetic disk 12 and the information recorded into the magnetic disk 12 is reproduced. When recording and reproducing the information, the carriage arm 17 is first driven by the actuator 19 having a magnetic circuit, and then the floating head sliders 15 are positioned at desired tracks on the rotating magnetic disk 12. The magnetic head is disposed at the tip end of the floating head slider 15 and the magnetic head sequentially approach each 1-bit area arranged in each track of the magnetic disk 12 along with the rotation of the magnetic disk 12. When recording the information, an electric recording signal is input into the magnetic head approaching the magnetic disk 12 in this way. The magnetic head applies a magnetic field to each 1-bit area in response to the input recording signal, and records the information carried by the recording signal as the magnetization direction of each 1-bit area thereof. When reproducing the information, the magnetic head generates an electric reproducing signal according to a magnetic field generated from each magnetization, thereby extracting the information recorded as the magnetization direction of each 1-bit area.
Next, the protrusion absorbing section pressing against the magnetic disk 12 will be described.
As shown in
If the HDD is configured such that the protrusion absorbing section is not present and the magnetic disks, the clamp body, the spacer body and the hub body are made to directly contact the disk surface, when foreign materials enter between the magnetic disk and any of the clamp body, the spacer body and the hub body at the time of assembling the HDD, the foreign materials become slight protrusions that contact the magnetic disk at the pressed face when the magnetic disk is pressed against any member. When the disk is pressed in a state where foreign materials are present, stress occurs in the magnetic disk substrate having a large thickness and hardness so that a distortion occurs in the magnetic disk where the foreign materials exist. As a result, flatness of the storage medium is lost so that defect areas where information recording or reproducing is disabled appear near the distortion intensively (since an under layer, a magnetic layer, a protection layer and the like formed on the disk substrate have the thickness of about several to several tens nm, an affect due to these layers can be ignored).
As shown in
The nature of the protrusion absorbing section is required to be soft enough to easily absorb a protrusion as described above, and further is required to be resistant to heat generated at the time of the rotation of the magnetic disk 12. Thus, the present embodiment employs a soft metal having a small hardness among metals as the material of the first protrusion absorbing section 14b, the second protrusion absorbing section 20b and the third protrusion absorbing section 21b. Such a soft metal includes gold, silver, copper, lead, tin, zinc or the like, for example. A soft metal of the same kind may be employed as the material of the first protrusion absorbing section 14b, the second protrusion absorbing section 20b and the third protrusion absorbing section 21b, or different types of soft metals may be employed.
Further, in the present embodiment, each protrusion absorbing section is made of a soft metal softer than the disk substrate of the magnetic disk 12 such that the protrusion is absorbed in each protrusion absorbing section before protrusive foreign materials cause a distortion in the magnetic disk 12.
The thickness in the vertical direction of each protrusion absorbing section in
The diameters of the clamp 20 and the hub 14 are designed to be smaller than the outer diameter of the magnetic disk 12 in order not to reach each storage area of the magnetic disk 12 where the information is stored. Specifically, in the case of a 2.5-inch magnetic disk (diameter of 65 mm), the diameter of the through hole at the center of the magnetic disk 12 is about 20 mm, and the second protrusion absorbing section 20b of the clamp 20 and the first protrusion absorbing section 14b of the hub 14 are abutted on a ring-shaped area having a width of about 1 to 2 mm around the through hole. By way of explanation using the cross-section view shown in
Hereinafter, the method of manufacturing the HDD 1 will be described focusing on the arrangement of the magnetic disks 12, the clamp 20, the spacer 21 and the hub 14. Although the HDD 1 of
Thin films each made of a soft metal between 5 μm and 20 μm inclusive are laminated and affixed at a part of the hub body 14a shown in
In this way, the hub 14 having the first protrusion absorbing section 14b, the clamp 20 having the second protrusion absorbing section 20b and the spacer 21 having the third protrusion absorbing section 21b are created.
Next, the hub body 14a is inserted into the though hole at the center of the first magnetic disk 12 (corresponding to the lower magnetic disk 12 shown in
Number | Date | Country | Kind |
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2007-024602 | Feb 2007 | JP | national |