JP2004055020A - Hard disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means to surely block an unauthorized user from retrieving contents recorded in a magnetic recording medium when the hard disk drive is unsealed. <P>SOLUTION: A hard disk drive is provided with an enclosure which contain a magnetic recording medium, an magnetic head, and an encryption/decryption circuit which performs encryption/decryption at least to signals for writing and reproducing to the magnetic recording medium and maintains inside pressure at a prescribed level; a sensor to detect unsealing of the enclosure; a first destructive means disposed facing a recording surface of the magnetic recording medium and destructs the recording surface of the magnetic recording medium in accordance with the unsealing of the enclosure; and a second destructive means for destructing the encryption/decryption circuit based on the detection result of the sensor. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hard disk device that cannot read content information recorded on a magnetic recording medium of a hard disk device so that the content information cannot be used when the housing is opened to obtain the information by illegal means. .
[0002]
[Prior art]
In current terminal devices such as personal computers, various contents are pre-installed on the hard disk drive, or the contents required by the user are downloaded to the hard disk drive via the Internet or the like to obtain them. It is becoming easier to use. Thus, with the widespread use of such content, it is required to reliably prevent unauthorized use of the content.
[0003]
Conventionally, in order to prevent unauthorized use, ID numbers and passwords have been set so that only the contractor can use the ID numbers and passwords. In some cases, the abuse was abused. For this reason, as a new countermeasure, an ID is embedded in each recording medium, for example, a content key necessary for using the content is created based on the ID, thereby granting the right to use the content. A system for encrypting the content has been proposed. In this way, unless the ID or the encryption / decryption chip embedded in the medium is stolen, unauthorized use of contents by not only amateurs but also manias can be completely prevented.
[0004]
[Problems to be solved by the invention]
However, even if the above-described measures for preventing fraud are taken, a person having specialized knowledge disassembles the hard disk device, reads the recording state of the recording surface of the recording medium using a magnetic head, and performs encryption / decryption. If the content of the signal processing in the chemical IC is decoded, it is possible in principle to steal the content, the content key, the ID, and the like.
[0005]
For this reason, a method has been proposed in which the magnetic recording medium is housed in a sealed housing, and when the housing is disassembled, the recording surface of the recording medium is deformed or melted so that it cannot be read by a magnetic head. Have been. However, it is difficult to achieve complete protection by using only this method, and thus it is necessary to use another destruction method in combination.
[0006]
The present invention has been made in view of the above problems, and provides a means for reliably preventing a content recorded on a magnetic recording medium from being taken out when an unauthorized user opens a hard disk device.
[0007]
[Means for Solving the Problems]
A hard disk drive according to the present invention that satisfies the above-described requirements contains a magnetic recording medium, a magnetic head, and at least an encryption / decryption circuit that encrypts / decrypts a signal that performs writing and reproduction on the magnetic recording medium. A housing maintained at a predetermined internal pressure, a sensor for detecting opening of the housing, and a sensor disposed to face a recording surface of the magnetic recording medium, and recording the magnetic recording medium with the opening of the housing. A first destruction means for destructing a surface and a second destruction means for destructing the encryption / decryption circuit based on a detection result of the sensor are provided.
[0008]
Here, the sensor may be a limit switch that is activated by a pressure difference between the inside of the housing and the outside of the housing when the housing is opened.
[0009]
Further, the first destruction means may be a rigid plate having a projection, and may contact the recording surface by a pressure difference between the inside of the housing and the outside of the housing to mechanically break the recording surface.
[0010]
Further, the first destruction means may be a permanent magnet plate, which may be close to the recording surface due to a pressure difference between the inside of the housing and the outside of the housing to magnetically destroy the recording surface.
[0011]
Further, the first destruction means may be a heater plate, which may be close to the recording surface due to a pressure difference between the inside of the housing and the outside of the housing, and thermally destroy the recording surface.
[0012]
Further, the second breaking means may break the circuit by applying an overcurrent to the circuit.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0014]
First, FIG. 1 shows a sectional structure of a hard disk drive 100 according to a first embodiment of the present invention.
[0015]
Currently, in a commercially available hard disk drive, a magnetic recording medium on which servo information, contents, a content key, etc. are recorded, a spindle motor for rotating the magnetic recording medium at a constant rotation speed, and writing / reading to / from a magnetic recording medium A surface provided with a magnetic head gimbal assembly, a voice coil motor for sliding the position of the magnetic head gimbal assembly, a signal processing circuit for writing / reading with the magnetic head, and a magnetic head gimbal assembly The surface on which the servo circuit for controlling the position is provided is disposed on the front and back through a partition in the middle of the housing.
[0016]
In the hard disk device 100 of the present invention, the housing of the device has a closed structure, and the magnetic system, the drive system, and the circuit system are arranged in one closed room in the housing. An object of the present invention is to prevent an unauthorized user from easily taking out both a magnetic recording medium on which content is recorded and a circuit for encrypting / decrypting the content.
[0017]
The hard disk drive 100 of the present invention has a closed two-chamber structure, and a housing 110 of the hard disk drive includes an inner sealed chamber 140 including a fixed frame 120 and a movable part 130, and an outer sealed chamber 150. Is constituted by a space between the housing 110 and the fixed frame 120 and the movable portion 130. The inside of the inner sealed chamber 140 is maintained at a predetermined pressure, and has a hard disk 160 as a magnetic recording medium, a head arm 162, a magnetic head 164, a spindle motor 166 for driving the hard disk 160, and a cipher for encrypting / decrypting contents. The circuit board 170 including the decoding circuit is arranged. The movable portion 130 is formed in a bellows shape made of a material such as rubber in order to increase a displacement amount due to a pressure difference between the inner sealed chamber 140 and the outer sealed chamber 150 and obtain a stable displacement amount. 160 are disposed at positions facing the recording surface 161.
[0018]
Next, FIG. 2 shows an outline of writing and reading of data on a recording medium by encryption / decryption.
[0019]
Each of the content and the content key is encrypted and stored in the magnetic recording medium in order to protect copyright against unauthorized use. In order to use the content, the content is decrypted, the content key is collated, and the content is used. Similarly, when a content and a content key are obtained from a content distributor and recorded on a magnetic recording medium, it is necessary to encrypt the content and the content key. When using the content, not only the content key but also, for example, a serial number embedded in the recording medium at the time of manufacturing may be used together.
[0020]
As described above, the content recorded on the magnetic recording medium cannot be used unless the magnetic recording medium is stolen in a normal state unless it can be decrypted. Therefore, when the closed chamber is opened, it is important to break not only the magnetic recording medium but also the encryption / decryption circuit.
[0021]
FIG. 3 shows a configuration in which the above-described magnetic recording medium and the encryption / decryption circuit are destroyed when the closed chamber is opened. At the center of the movable portion 130, as a first destruction means, a destruction means 180 having substantially the same size as the magnetic recording medium 160 is provided as opposed to a recording surface 161 including a magnetic layer of a hard disk 160 as a magnetic recording medium. It is fixed via a support member 182. A guide hole 182a is formed at the center of the support member 182, and a shaft 168 of the spindle motor 166 is fitted therein. As the destruction means 180, for example, a flaw generating plate which is a rigid plate having a protruding portion which is pressed against the surface of the medium to generate a damage, or a strong external magnetic field is generated by pressing against the surface of the medium, and the direction of magnetization is reduced. Examples include a permanent magnet plate that is aligned in the direction, a heater plate that heats the surface of the medium to the Curie temperature at which data recorded on the medium disappears in magnetization.
[0022]
The fixed frame 120 is provided with a limit switch 190 for detecting the movement of the movable part 130 by contact with a detection bar 132 provided at the tip of the movable part 130. In order to properly set the pressure between the sealed chamber 140 and the outer sealed chamber 150, a one-way valve 200 as shown in FIG. 5 is mounted. The one-way valve 200 has a structure in which the inner sealed chamber 140 flows out when the pressure is higher than the outer sealed chamber 150, and conversely, when the pressure is lower, the inflow is prevented. That is, the one-way valve 200 includes a ball 204 having a predetermined diameter movably mounted on the central enlarged portion 202, and first and second seat portions 206 and 208 are formed on both sides of the enlarged portion 202. Have been. As shown in FIGS. 5A and 5B, the first seat portion 206 located on the outer sealed chamber 150 side is sealed by the seating of the ball 204, whereas the first seat portion 206 is sealed on the inner sealed chamber 140 side. Is set so that a gap is formed even when the ball 204 is seated. Further, a pressure release port 122 is provided in the housing 110 of the hard disk device 100. Reference numeral 170 denotes a circuit board on which circuits for controlling the hard disk device 100 and the like are arranged, and the arrangement position may be any position.
[0023]
In the hard disk device configured as described above, the limit switch 190, which is a sensor for detecting opening, provided on the fixed frame 120 is operated in accordance with the movement of the movable portion 130, and as shown in FIG. By applying a voltage from the primary or secondary battery 302 capable of supplying a voltage higher than the voltage that normally operates to the encryption / decryption circuit 300 to the overcurrent, the circuit generates heat and burns. To prevent normal operation. At present, the encryption / decryption circuit is formed into an IC by an integrated technique, and the range of influence of the above-mentioned burnout extends to the entire encryption / decryption IC 300. Further, even when the voltage from the primary or secondary battery 302 is the same as the voltage 304 that normally operates, for example, an overcurrent can be made to flow by directly applying the voltage to the input / output unit of the circuit.
[0024]
Next, the assembly of the hard disk device having such a configuration will be described.
1) Assemble and wire all parts of the hard disk.
2) The joining surfaces of the housings are welded and joined by an ultrasonic welding device to form an airtight structure.
3) The posture of the hard disk drive is set so that the ball of the one-way valve moves toward the housing, and the pressure is reduced by a true chamber pump through a pressure release port provided in the housing.
4) When the pressure reaches a predetermined value, the evacuation is stopped, the attitude of the hard disk drive is rotated by 180 degrees, and the ball of the one-way valve is moved to the inside of the closed chamber. In this state, if the pressure on the housing side is slightly increased, the ball of the one-way valve is pushed against the side surface of the valve due to the pressure difference, and the inner sealed chamber is sealed.
5) Seal the pressure release port of the housing using a means such as heat welding.
[0025]
A gas having a low content in air such as Ar or a gas not contained in air such as He is sealed in the housing, and a change in the concentration of the gas can be detected instead of the limit sensor. An opening detection sensor may be used.
[0026]
When the hard disk drive thus configured is opened, the pressure in the housing becomes equivalent to 1 atm, and a large pressure difference is generated between the inside of the enclosure and the inner closed chamber. The movable part is deformed and moved to a position where it is balanced. As a result, the recording surface is destroyed by the medium destruction mechanism provided at the tip of the movable part, and data cannot be normally obtained from the magnetic recording medium. In addition, the limit switch provided on the fixed frame operates in accordance with the movement of the movable part, and burns out the encryption / decryption circuit. In this way, the copyright can be protected against plagiarism of the content by an unauthorized user.
[0027]
【The invention's effect】
As described above, according to the present invention, the magnetic recording medium and the encryption / decryption circuit are housed in a sealed casing, and when the casing is disassembled, the recording surface of the recording medium is removed. The recording state can be more reliably determined by destructing the two parts by taking measures to make the recording state unreadable by the magnetic head and to make the encryption / decryption IC unusable even if it is read. Can be prevented, and the copyright of the content provider can be more completely protected.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an embodiment of a hard disk drive according to the present invention.
FIG. 2 is a diagram showing an outline of writing and reading of data on a recording medium by encryption / decryption.
FIG. 3 is a diagram showing a configuration of a destruction unit in one embodiment of the hard disk device according to the present invention.
FIG. 4 is a diagram showing a circuit configuration for destroying an encryption / decryption circuit according to the present invention.
5A and 5B are cross-sectional views showing a structure of a one-way valve according to the present invention, in which FIG. 5A is a front view, FIG. 5B is a side view, and FIGS. (C) shows a sealed state.
[Explanation of symbols]
REFERENCE SIGNS LIST 100 hard disk drive 110 housing 120 fixed frame 122 pressure release port 130 movable section 132 detection bar 140 inner sealed chamber 150 outer sealed chamber 160 magnetic recording medium 161 recording surface 162 head arm 164 magnetic head 166 spindle motor 168 shaft 170 circuit board 180 destruction Means 182 Support member 190 Limit switch 200 One-way valve 202 Large diameter portion 204 Ball 206 Seat portion 300 Encryption / decryption IC
302 Primary / secondary battery 304 Power supply during normal operation

Claims (6)

A housing housing a magnetic recording medium, a magnetic head, and at least an encryption / decryption circuit for encrypting / decrypting a signal for writing / reproducing to / from the magnetic recording medium, and maintained at a predetermined internal pressure;
A sensor for detecting opening of the housing,
A first destruction means disposed to face the recording surface of the magnetic recording medium, and with opening of the housing, destroying the recording surface of the magnetic recording medium,
A hard disk drive, comprising: a second destruction unit that destroys the encryption / decryption circuit based on a detection result of the sensor. 2. The hard disk drive according to claim 1, wherein the sensor is a limit switch that is activated by a pressure difference between the inside and outside of the housing when the housing is opened. The said 1st destruction means is a rigid board which has a projection, It contacts the said recording surface by the pressure difference of the inside of the said housing | casing, and the outside of a housing | casing, The said recording surface is mechanically destroyed, The Claims characterized by the above-mentioned. 3. The hard disk device according to 1 or 2. 2. The method according to claim 1, wherein the first destruction unit is a permanent magnet plate, closes to the recording surface by a pressure difference between the inside of the housing and the outside of the housing, and magnetically destroys the recording surface. 3. 3. The hard disk device according to 2. 3. The recording medium according to claim 1, wherein the first destruction unit is a heater plate, which is close to the recording surface due to a pressure difference between the inside of the housing and the outside of the housing, and thermally destroys the recording surface. 4. The hard disk device according to 1. 6. The hard disk drive according to claim 1, wherein the second destruction unit destroys the circuit by applying an overcurrent to the circuit.

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