JP3299947B2 - Hard disk acoustic inspection method, hard disk acoustic inspection device, and program storage medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting a hard disk for scratches (especially, dents and the like in a CSS (contact start / stop) area) on a hard disk.

[0002]

2. Description of the Related Art Power supply OF
In some cases, a CSS area where the head stands by at the time of F is provided on the disk.

[0003] In a hard disk having a CSS area, a head may collide with the CSS area due to vibrations during transportation, and may make a dent.

FIG. 7 is an explanatory view showing the relationship between the dents formed in the CSS area of the hard disk and the height of the head. When the disk 100 is rotated and the head 101 flies, the height is 30 nm to 80 nm from the disk surface 102. On the other hand, the height of the dent 103 is about 15 nm to 50 nm. Such dents cannot be found by ordinary reading and writing inspection. A hard disk with such a dent is liable to cause a failure due to dust or the like generated when the dent 103 and the head 101 collide with each other one to two months after actually starting use.

[0005] Such a dent can be found by opening the hard disk. However, the opened hard disk has no value as a product because dust and the like are mixed therein. Therefore, there has been a demand for a method capable of performing inspection without opening the hard disk.

On the other hand, as a method for inspecting a scratch on a disk in a process of manufacturing a hard disk, there is a technique disclosed in Japanese Patent Application Laid-Open Nos. 4-283421 and 10-206340.

In these techniques, a mechanism for inspecting vibration is attached to an arm to which a head is attached, and the vibration of the arm is directly detected to determine whether there is a flaw caused by the vibration.

[0008]

However, the above-mentioned conventional inspection method requires a mechanism for detecting vibrations in the arm, and thus requires much labor and cost for manufacturing. Also, it cannot be applied to hard disks that are already widely used in the world. Moreover, the conventional inspection method described above
After the hard disk cover is attached, the arm cannot be directly accessed, so it is impossible to inspect the hard disk after commercialization.

The present invention makes it possible to find a scratch (particularly, a dent in a CSS area) on a hard disk without opening the hard disk. Moreover, the present invention makes it possible to apply the present invention to hard disks which are already popular in the world without any trouble and cost in manufacturing the hard disk.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 picks up vibration generated when a head of the hard disk collides with a scratch of the disk from vibration transmitted to the housing of the hard disk. A hard disk acoustic inspection method characterized by inspecting the disk for the presence or absence of a scratch.

[0011] The invention according to claim 2 is the above-described claim 1.
In the invention according to the first aspect, the inspection is performed when the drive of the disk is stopped and the disk is rotating by inertia.

According to a third aspect of the present invention, there is provided a hard disk acoustic inspection apparatus comprising means for picking up vibration generated when a head of the hard disk collides with a scratch on the disk from vibrations transmitted to the housing of the hard disk. is there.

The invention according to claim 4 is the above-described claim 3.
In the invention according to the fifth aspect, the pickup means is a contact microphone.

[0014] The invention according to claim 5 is the above-described claim 3.
In the invention according to the fifth aspect, the pickup means is an optical head.

The invention according to claim 6 is the above-described claim 3.
The present invention according to the invention is characterized by further comprising means for amplifying the vibration picked up by the picking up means as sound and outputting the amplified sound to the outside.

The invention according to claim 7 is the above-described claim 3.
The invention according to the above (1), further comprising a display for displaying a vibration picked up by the pickup means as a waveform.

The invention according to claim 8 is the above-described claim 3.
The invention according to the above aspect further comprises means for converting the vibration picked up by the pickup means into a digital value and storing the digital value.

The invention according to claim 9 is the invention according to claim 8 described above.
The invention according to the fifth aspect is characterized by further comprising means for detecting a sound of collision between a head of the hard disk and a scratch on the disk based on the vibration stored by the storing means.

In a tenth aspect based on the ninth aspect, the detecting means includes a function of controlling a power supply of the hard disk, a function of monitoring a vibration state, and a sound output to the outside. Characterized in that it has a function of changing the amplification factor.

According to an eleventh aspect of the present invention, in the above-mentioned ninth aspect, the detecting means has a function of notifying an observer of a testable timing.

A twelfth aspect of the present invention is characterized in that, in the eighth aspect of the present invention, a means for performing a wavelet conversion of the vibration converted into a digital value is provided.

In a thirteenth aspect of the present invention based on the ninth aspect, the detecting means cuts out an area immediately before the stop of the rotation of the disk based on the vibration stored in the storage unit. It is characterized in that a flaw in the CSS area of the disc is analyzed.

According to a fourteenth aspect of the present invention, in the above-described ninth aspect, the detecting means analyzes the presence or absence of a scratch on the disk by using a ratio of an average level to a peak level of acoustic data. Features.

According to a fifteenth aspect of the present invention, in the ninth aspect of the present invention, the detecting means uses the periodicity of the peak level in the audio data and the deceleration characteristics of the spindle of the hard disk to determine whether the disk is damaged. Is analyzed.

According to a sixteenth aspect of the present invention, in the above-described ninth aspect, the detecting means can store a plurality of types of hard disk parameters, and use a parameter corresponding to the type of hard disk to be inspected. The presence or absence of a flaw is analyzed.

A seventeenth aspect of the present invention is characterized in that, in the third aspect of the present invention, there is provided means for storing acoustic data in a state of an original sound at the time of inspection.

[0027] The invention according to claim 18 analyzes the presence or absence of a scratch on the disk based on the vibration transmitted to the housing of the hard disk, using the ratio of the average level and the peak level of the audio data, or A program medium for storing a program for analyzing the presence or absence of a scratch on a disk using the periodicity of the peak level and the deceleration characteristics of the spindle of the hard disk.

According to a nineteenth aspect of the present invention, in the first aspect of the present invention, the inspection is performed in a reduced pressure chamber.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention detects a vibration generated when a head of a hard disk collides with a scratch on the disk from vibration transmitted to a housing of the hard disk, thereby opening a hard disk cover without opening the cover. It is possible to inspect the presence or absence of flaws in the CSS area of the disc.

In the art, it is completely unexpected that the vibration generated when the head of the hard disk collides with the scratch of the disk is transmitted to the housing of the hard disk. Therefore, for example, Japanese Patent Application Laid-Open No. 4-283421
In JP-A-10-206340 and JP-A-10-206340, the presence or absence of a scratch on the disk cannot be inspected unless a special mechanism for detecting vibration is provided on the arm. On the other hand, the present invention can inspect the disk for scratches without providing such a special mechanism.

Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, each figure is only schematically shown to the extent that the present invention can be understood. Further, in each of the drawings, common elements are denoted by the same reference numerals, and description thereof is omitted.

<First Embodiment> Hereinafter, the present invention will be described in detail by taking, for example, a case in which the presence or absence of a flaw in a CSS area of a disk is inspected.

FIG. 1 is a functional block diagram showing an example of an embodiment of a hard disk acoustic inspection apparatus according to the present invention.

In FIG. 1, reference numeral 1 denotes a contact microphone as a means for picking up the vibration of the hard disk 2. The contact microphone 1 makes contact with the housing of the hard disk 2 to detect vibration transmitted to the housing and generates an analog electric signal. As the contact microphone 1, a vibrator connected to a piezoelectric element and a mechanism (piezoelectric microphone) in which vibration of the vibrator is directly transmitted to the piezoelectric element may be used.

An amplifier 3 amplifies vibration transmitted to the housing of the hard disk 2 picked up by the contact microphone 1. This amplifier 3 has a variable amplification factor.

Reference numeral 3a denotes an A / D converter for A / D converting the output of the contact microphone 1 amplified by the amplifier 3, and 3b denotes a digital signal of the output of the contact microphone 1 amplified by the amplifier 3 by the A / D converter. This is a storage device for storing the converted data.

4 is a contact microphone 1 amplified by the amplifier 3
Is a speaker that outputs the output of the speaker as audio. Note that headphones may be used instead of the speakers.

Reference numeral 5 denotes a control device, which is a start switch (switch) 5a for starting an inspection, a display LED 5b for notifying an observer that an inspection is possible, and ON / OFF control of the power supply of the hard disk 2. A circuit 5c for monitoring the state of the hard disk 2, a circuit 5e for controlling the amplification factor of the amplifier 3, a circuit 5f for determining the presence or absence of noise from the output of the amplifier 3, and storing data in the storage device 3a. A readout circuit 5g and a hard disk power supply unit 5h are provided.

Between the hard disk 2 and the controller 5, power is supplied from the controller 5 to the hard disk 2.
It is connected to a power connector of the hard disk 2 and to a signal interface connector for ON / OFF control and monitoring of the status of the hard disk 2.

The operation of the control device 5 will be briefly described. When the control device 5 detects that the start switch 5a has been pressed, the control device 5 turns on the power supply to the hard disk 2 and monitors a signal from the hard disk 2 to monitor the signal from the hard disk 2. When it is detected that the hard disk 2 has started up in response to the ready signal, the power supply to the hard disk 2 is turned off after a lapse of a predetermined time. Thereby, the hard disk 2
In this case, the motor (not shown) stops and the disk rotates by inertia.

Then, the controller 5 controls the hard disk 2
When the power supply to is turned off, the amplifier 3 is instructed to increase the gain over a predetermined period of time. Amplifier 3
Receives the instruction and increases the output from the contact microphone 1 while increasing the amplification factor to a predetermined value.
-Output to the D converter 3a. At this time, the control device 5
The noise included in the output received from the amplifier 3 is monitored by the circuit 5f. The A / D converter 3a converts the output received from the amplifier 3 into digital data and outputs the digital data to the storage device 3b.

When the amplification factor of the amplifier 3 rises to a predetermined value, the control device 5 turns on the display LED 5b to notify the observer that the test is possible, and also stores the A / D converter in the storage device 3b. The storage of the data output from 3a is started.

Thereafter, rotation of the disk due to inertia is stopped. Then, when the noise becomes equal to or less than the predetermined value, the controller 5 instructs the amplifier 3 to lower the gain. The amplifier 3 receives this instruction and lowers the amplification factor to a predetermined value. Further, the control device 5 controls the display L
The ED 5b is turned off and the observer is notified that the timing at which the inspection is possible has been missed, and the storage in the storage unit 3a is stopped.

FIG. 2 is a perspective view showing an example of the configuration of a hard disk. FIG.
(B) shows a state where the cover is attached.

Reference numeral 6 denotes one or more disks.
It is rotated by a motor (not shown). An arm 7 has a head 8 for reading and writing data from and to the disk 6 at its tip, and a rear end supporting the arm 7 to swing along the surface of the disk 6 by a drive source (not shown). It is rotatably supported by the mechanism.

Reference numeral 9 denotes a base on which the disk 6, a motor (not shown) for rotating the disk 6, a support mechanism and a drive mechanism for the arm 7, a substrate and the like are mounted.

Reference numeral 10 denotes a plurality of mounting portions for supporting the cover 11 on the base 9, 12 denotes screw holes provided in the mounting portion 10, 13 denotes screws for fixing the cover 11 to the base 9, and 14 denotes the hard disk 2. This is a screw hole used when attaching to a computer or the like.

Reference numeral 15 denotes a power supply connector for connecting a power supply, and 16 denotes an interface connector for connecting a signal line.

The outline of the operation of the hard disk 2 will be described below. The hard disk 2 has a CS that is in a standby state with the head 8 in contact with the disk 6 when the power is turned off.
An S area 6b is provided along the innermost circumference of the disk 6.

When the power of the hard disk 2 is turned on, the disk 6 starts rotating. When the disk 6 rotates, the head 8 floats due to the airflow and the CSS area 6a
Take off from. When the head 8 takes off, the arm 7 is rotated to move the head 8 from the CSS area 6a to the read / write area 6b.

When the power is turned off, the arm 7 is rotated to return the head 8 to the CSS area 6a, and the rotation is stopped while rotating the disk 6 by inertia. As the rotation of the disk 6 decreases, the head 8 descends, the rotation of the disk 6 stops, the head 8 lands on the CSS area 6a, and the operation ends.

FIG. 3 is an external perspective view showing an example of the configuration of the hard disk acoustic inspection apparatus of the present invention.

Reference numeral 20 denotes a hard disk acoustic inspection device, 21
Denotes a mounting unit for mounting the hard disk 2 to be inspected.

Reference numeral 5a denotes the start switch described with reference to FIG. 1, 1 denotes a contact microphone, 4 denotes a speaker, and 5b denotes a display LED.
Reference numeral 22 denotes a headphone terminal, which enables sound output to the speaker 4 to be output from headphones (not shown).

Reference numeral 23 denotes a power connector 1 of the hard disk 2
Reference numeral 24 denotes a power connector connected to the hard disk 2 and reference numeral 24 denotes an interface connector connected to the interface connector 16 of the hard disk 2.

FIG. 4 is a schematic sectional view showing an example of the mounting structure of the contact microphone 1 described in FIG. Contact microphone 1
Is mounted on the bottom surface of the mounting portion 21 so as to be pressed by the spring 25 and protrude from the bottom surface. Hard disk 2
Is mounted on the mounting portion 22 such that the cover 11 faces down. When the hard disk 2 is mounted on the mounting unit 21, the contact microphone 1 is pressed by the spring 25 from below and sinks from above, so that the contact microphone 1 comes into close contact with the hard disk 2. Note that the contact microphone 1 has a sharp pointed mechanism for detecting vibration. When the pickup means having such a shape is attached to either the screw 13 or the screw hole 14, the vibration of the hard disk 2 can be detected satisfactorily.

FIG. 5 is an external perspective view showing a modified example of the hard disk acoustic inspection apparatus of the present invention.

Reference numeral 30 denotes a hard disk acoustic inspection device, 5a
Is a start SW described in FIG. 1, 1 is a contact microphone, 4 is a speaker, and 5b is a display LED. A cable 31 connects the contact microphone 1 and the hard disk acoustic inspection device 30. Reference numeral 32 denotes a headphone terminal which enables sound output to the speaker 4 to be output from a headphone (not shown).

33 is a power connector 1 of the hard disk 2
5, a power connector for connecting the power connector 33 and the hard disk acoustic inspection device 30; 35, an interface connector for connecting to the interface connector 16 of the hard disk 2; 36, an interface connector 35; Is a cable that connects

The hard disk acoustic inspection apparatus having the configuration shown in FIG. 5 is configured so that the observer presses the contact microphone 1 against the hard disk 2. Since the contact microphone 1 has a sharp point of a mechanism for detecting vibration, the vibration of the hard disk 2 can be detected satisfactorily when the contact microphone 1 is attached to either the screw 13 or the screw hole 14.

FIG. 6 is a time chart showing the details of the hard disk acoustic inspection method according to the present invention, and the details of the operation will be described below. FIG. 6A is a graph showing the lapse of time and the change in noise with the noise level on the vertical axis and time on the horizontal axis, and FIG. 6B is a start switch sequence showing the state of the start SW 5a. 6C is a power sequence showing the state of power control, FIG. 6D is an interface sequence showing the state of the hard disk 2, and FIG.
(E) is a gain sequence showing the state of the amplifier 3, and FIG.
(F) is a display LED sequence indicating the state of the display LED 5b.

First, the hard disk 2 to be inspected is set in the hard disk acoustic inspection apparatus. Here, when the hard disk acoustic inspection device has a structure as shown in FIG.
The hard disk 2 is mounted on the mounting portion 21 with the cover 11 facing down. At this time, the power connector 15 of the hard disk 2 is connected to the power connector 23 of the hard disk acoustic inspection device 20, and the interface connector 16 of the hard disk 2 is connected to the interface connector 24.

Then, the contact microphone 1 is connected to the hard disk 2
Contact the screw 13 of FIG.

FIG. 5 shows a hard disk acoustic inspection apparatus.
In the case of the structure shown in FIG. 2, the power connector 15 of the hard disk acoustic inspection device 30 is connected to the power connector 15 of the hard disk 2, the interface connector 35 is connected to the interface connector 16 of the hard disk 2, and the contact microphone 1 is connected to the housing of the hard disk 2. The surface of the body 9 is brought into contact. At this time, when the contact microphone 1 is brought into contact with the screw 13 or the screw hole 14 on the side surface of the housing 9, the vibration of the hard disk 2 can be picked up satisfactorily.

By the above operation, the contact microphone 1 can detect the vibration of the hard disk 2, and the control device 5 can drive the hard disk 2 and monitor the signal.

Next, the start switch 5a is pressed.

When the control device 5 detects that the start switch 5a is turned on, the control device 5 turns on the power supply to the hard disk 2 and issues an instruction to start rotation. Thus, the disk 6 of the hard disk 2 starts rotating. When the disk 6 starts rotating, the head 8 is moved in the CSS area 6a by airflow.
Starts takeoff and when the head 8 floats, the arm 7 is rotated to move the head 8 to the read / write area. When the head 8 is moved to a predetermined position as described above, the hard disk 2 outputs that it is in the ready state.
The control device 5 monitors the signal from the hard disk 2 and, upon receiving a notification of the ready state from the hard disk 2 and detects that it has started up, counts a predetermined time t1 by a timer therefrom,
Turn off the power to the. Here, the predetermined time t1
Is the time from the start-up of the hard disk 2 until the head stops operating, and is about 1 second.

When the power supply of the hard disk 2 is turned off, the arm 7 rotates and the head 8 returns to the CSS area 6a. Since the disk 6 is rotating by inertia, the rotation gradually slows down and the head 8 stops landing. Start.

After turning off the power supply to the hard disk 2, the control device 5 sets a predetermined time t 2
And an instruction is issued to gradually increase the amplification factor of the amplifier 3 to a predetermined value, for example, from 0 to 100% during the predetermined time t2. Here, the time t2 is a time until the noise generated when the head 8 returns to the CSS area 6a is attenuated, and is about 2 seconds.

Upon receiving this instruction, the amplifier 3 increases the amplification factor to a predetermined value, and outputs the vibration of the hard disk 2 from the speaker 4 as sound. Further, when the time t2 has elapsed and the amplification factor of the amplifier 3 has increased to a predetermined value, the control device 5 turns on the display LED 5b and notifies the observer that the inspection is possible. Further, the control device 5
When the amplification factor of the amplifier 3 increases to a predetermined value after the elapse of the time t2, the vibration of the hard disk 2 output from the AD converter 3a is converted into digital data and stored in the storage device 3b. .

As described above, after the power to the hard disk 2 is turned on, the power to the hard disk 2 is turned off.
Until the time t2 elapses, the amplification factor of the amplifier 3 is "0%" and no output is made from the speaker 4. Thus, the noise at the time of startup, the rotation sound of the motor, the noise when the head 8 returns to the CSS area 6a, and the like are not heard by the observer, and the observer is not confused by such noise. Then, when the power supply to the hard disk 2 is turned off and the time t2 has elapsed, the amplification factor of the amplifier 3 is set to “100%” so that the output from the speaker 4 is made. When the power supply to the hard disk 2 is turned off and the time t2 has elapsed, the disk 6 is rotating by inertia while the head 8 is in the CSS area 6a, and if there is a dent in the CSS area 6a. The head 8 that has started descending collides with the dent and is vibrated and transmitted to the base 9 and the cover 11. The vibration is output from the speaker 4 as sound, so that the presence or absence of a dent can be determined. For example, if there is a dent at one place, a periodic sound can be heard.

At this time, as described above, since the disk 6 is rotating by inertia, other noises are small, and the sound of collision with the dent of the head 8 is not buried in the noise.

Therefore, the observer can easily determine the presence or absence of a dent from the sound output from the speaker 4.

When the control device 5 receives the output from the contact microphone 1 amplified by the amplifier 3 and determines that the noise has become equal to or less than a predetermined value, the control device 5 instructs the amplifier 3 to reduce the amplification factor and displays the signal. The LED 5b is turned off to notify the end of the inspection. Upon receiving this instruction, the amplifier 3 lowers the amplification rate and eliminates the output from the speaker 4,
Keep unwanted noise from being heard by observers.

Further, when the control device 5 determines that the noise has become equal to or less than the predetermined value, the control device 5 stops storing data in the storage device 3b.

As described above, the vibration of the hard disk 2 from the time when the power supply to the hard disk 2 is turned off to the time when the time t2 has elapsed until the noise becomes equal to or less than the predetermined value is digitized and stored, so that it is necessary for the analysis. Data can be saved.

<Second Embodiment> The first embodiment described above
The observer hears the vibration caused by the collision between the head 101 and the dent 103 in the CSS area and determines whether or not the dent 103 exists. Therefore, in the first embodiment, an erroneous determination may be made due to individual differences between observers or ambient noise at the time of observation. Therefore, in the second embodiment, the head 101 and the CS 101
Vibration caused by the collision of the dents 103 in the S area is displayed on a display as a waveform, so that an observer can visually determine.

FIG. 8 is a diagram showing the configuration of the second embodiment. Reference numeral 201 denotes an inspection apparatus according to the second embodiment. 20
2 receives an output from the contact microphone 1, generates PCM-format digital data from the output, and
Sound device to send to. Reference numeral 203 denotes a buffer that receives PCM data from the sound device 202 and stores the PCM data. 204 is P from buffer 203
A waveform data conversion unit that reads out CM data and generates waveform data based on a predetermined algorithm. 205
Is a display that receives the waveform data generated by the waveform data conversion unit 204 via the buffer 203 and displays it. A control unit 206 controls the entire apparatus. An operation unit 207 receives a viewer's input and sends to the control unit 206 a signal instructing start and end of observation, and a signal instructing a change in display position and display magnification of waveform data.

FIG. 9 is a time chart showing a change in vibration transmitted to the casing 9 from when the hard disk 2 is started to when it is stopped. As shown in the figure, the noise due to the dent 103 has a high noise level such as a rotation sound of a motor (not shown) and a seek sound of the head 8 in a normal operation state (ie, at the time of start-up or idling). It cannot be observed. However, when the power is turned off and the rotation of the motor is stopped, the disk is rotating by inertia for a while. At this time, since the noise level other than the dent 103 is low, the noise due to the dent 103 can be observed. Become like

The second embodiment will be described below with reference to FIGS. 10 and 11.
The operation of this embodiment will be described. FIG. 10 is a flowchart showing the operation of the second embodiment. FIG. 11 is a diagram showing a noise waveform due to a dent displayed on the display. If there is a strong periodic peak, it indicates that there is a dent.

The observer mounts the hard disk 2 on the inspection device 2
01, and the power is turned on by operating the operation unit 207 (step (hereinafter, referred to as S) 1).

The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 has completely started up, operates the operation unit 207 to give an instruction to start inputting (S2). In response to this instruction, the sound device 202 receives an output from the contact microphone 1 and receives P from the output.
The digital data in the CM format is generated and transmitted to the buffer 203 (S3). The buffer 203 receives the PCM data from the sound device 202 and stores it (S4).

The observer operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S5).

After a predetermined time has elapsed since the rotation of the motor was stopped, the observer operates the operation unit 207 to give an instruction to end the input (S6). Thereby, the inspection device 201
Ends the data acquisition.

The waveform data conversion unit 204
The PCM data is read out from No. 3 and waveform data is generated based on the data (S7). Display 205
Receives the waveform data generated by the waveform data conversion unit 204 via the buffer 203 and displays it (S8).

The observer operates the operation unit 207 to adjust the display position and the display magnification of the waveform (S9). Then, the observer determines the presence or absence of a dent by checking the presence or absence of a periodic strong peak as shown in FIG. 11 from the displayed waveform.

Hereinafter, the flow returns to S1 when checking another hard disk, and ends when not checking (S10).

As described above, in the second embodiment, the dent 103
Can be visually determined. Therefore, in the second embodiment, the presence or absence of the dent 103 is less likely to be affected by the individual difference of the observer and the environment at the time of the observation, and the presence or absence of the dent 103 is determined more stably than the case where the presence or absence of the dent 103 is judged audibly. It becomes possible.

<Third Embodiment> In the second embodiment, when the dent 103 is large, that is, when the noise due to the dent 103 is strong, a waveform as shown in FIG. 11 appears. However, when the dent 103 is small, that is, the dent 10
When the noise due to No. 3 is small, the waveform is as shown in FIG. In this case, the noise due to the dent 103 is buried in another noise (for example, noise of a motor (not shown) or the surface of the disk 6), and thus does not periodically show a strong peak. Therefore, when the dent 103 is small, the observer cannot make a determination only by looking at the waveform. Therefore, in the third embodiment, by configuring as follows, even when the dent 103 is small, the noise due to the dent 103 is clearly shown as a waveform. FIG. 14 is a waveform diagram when the dent is small in the second embodiment.

That is, the third embodiment is obtained by adding the wavelet conversion unit 208 to the second embodiment.
FIG. 12 is a diagram showing the configuration of the third embodiment.

In the third embodiment, by utilizing the fact that the noise due to the dents 103 periodically shows a strong peak, the data is subjected to Wavelet conversion so as to exhibit a temporal characteristic. Note that Wavelet conversion is performed, for example, in “Digital Signal Processing Handbook (edited by the Institute of Electronics, Information and Communication Engineers)” (Ohm Co., Ltd., January 31, 1993)
As described in Section 4.6 (Wavelet Transformation), which is a well-known technique, it will not be described in detail here.

The operation of the third embodiment will be described below with reference to FIG. FIG. 13 is a flowchart showing the operation of the third embodiment.

The observer mounts the hard disk 2 on the inspection device 2
The power is turned on by operating the operation unit 207 (S21).

The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 has completely started up, operates the operation unit 207 to give an instruction to start inputting (S22). In response to this instruction, the sound device 202 receives an output from the contact microphone 1, generates PCM-format digital data from the output,
(S23). The buffer 203 receives the PCM data from the sound device 202 and stores it (S24).

The observer operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S25).

After a predetermined time has elapsed since the rotation of the motor was stopped, the observer operates the operation unit 207 to give an instruction to end the input (S26). Thereby, the inspection device 20
1 ends the data acquisition.

Wavelet conversion section 208 reads out the PCM data from buffer 203 and performs Wavelet conversion.
The converted PCM data is generated, transmitted to the buffer 203, and stored in the buffer 203 (S2).
7). The waveform data conversion unit 204 reads out the Wavelet-converted PCM data from the buffer 203 and generates waveform data based on the data (S2).
8). The display 205 includes a waveform data conversion unit 204
Is received via the buffer 203 and displayed (S29).

The observer operates the operation unit 207 to adjust the display position and the display magnification of the waveform (S30). Then, the observer determines the presence or absence of a dent by checking the presence or absence of a periodic strong peak as shown in FIG. 11 from the displayed waveform.

Thereafter, the flow returns to S21 when checking another hard disk, and ends when not checking (S31).

The Wavelet transform, for example, differs from the Fourier transform in which only frequency is decomposed, and can decompose frequency and time simultaneously. On the other hand, dent 1
As a result of the experiment, when the dent 103 was small, a sharp periodic peak was observed around 4 KHz to 8 KHz, and it was found that other noise was relatively small in this frequency band. Therefore, in the third embodiment, the PCM data is read out from the buffer 203, and the
The data is decomposed into a plurality of data for each frequency by t conversion. As a result, the third embodiment, as shown in FIG.
It becomes possible to express a waveform that periodically shows a strong peak around z to 8 KHz. Therefore, observer 103
Can be determined. FIG. 15 is a dent waveform diagram according to the third embodiment, showing a case where the dent is small.

As described above, in the third embodiment, the data is
The time characteristic can be expressed by performing the avelet conversion. Thereby, the third embodiment is, in particular,
Even when the dent 103 is small, that is, even when the noise due to the dent 103 is small, a waveform that periodically exhibits a strong peak can be represented. For this reason, the third embodiment enables more accurate determination than the second embodiment.

<Fourth Embodiment> In the third embodiment, all the fetched data is subjected to Wavelet conversion. However, since the Wavelet transform requires a floating-point operation in an amount proportional to the data length, if a dedicated floating-point operation coprocessor is not implemented,
In order to process data, an enormous memory capacity (about 40 to 50 times the integer operation) and processing time are required. Therefore, in the fourth embodiment, a period in which the characteristics of the dent 103 are strongly exhibited is cut out, and only this period is subjected to Wavelet conversion.

The operation of the fourth embodiment will be described below with reference to FIG. FIG. 16 is a flowchart showing the operation of the fourth embodiment.

The observer operates the operation unit 207 to give an instruction to start inputting (S41). Sound device 202
Receives this instruction, receives an output from the contact microphone 1, generates PCM-format digital data from the output, and transmits it to the buffer 203 (S42). At this time,
The sound device 202 transmits silent data to the buffer 203 until the hard disk 2 starts. The buffer 203 receives the PCM data from the sound device 202 and stores it (S43).

Next, the observer sets the hard disk 2 on the inspection device 201 and operates the operation unit 207 to turn on the power of the hard disk 2 (S44). Thereby, the hard disk 2 starts. The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 completely starts up, operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S45). Thereafter, the disk 6 of the hard disk 2 keeps rotating for a while due to inertia. In the meantime, the inspection device 201 keeps capturing data,
The fetched data is stored in the buffer 203. Thereafter, the disk 6 stops rotating. As a result, the data is silenced. At this point, the inspection apparatus 201 ends the data acquisition.

Thereafter, the waveform data converter 204 of the inspection apparatus 201 reads out the PCM data from the buffer 203, cuts out the area immediately before the rotation of the hard disk 2 is stopped (S46), and stores the PCM data in the cut out area in the buffer 203. To be stored. The details of the extraction will be described later.

After that, the Wavelet conversion unit 208
The PCM data in the area cut out by the waveform data conversion unit 204 is read out from the buffer 203,
Et conversion is performed to generate PCM data (S47).
The Wavelet conversion unit 208 transmits the PCM data that has been subjected to Wavelet conversion to the buffer 203, and stores the PCM data in the buffer 203. Waveform data converter 204
Reads the wavelet-converted PCM data from the buffer 203 and generates waveform data based on the data (S48).

The display 205 stores the waveform data generated by the waveform data conversion unit 204 in the buffer 203.
And displays it (S49).

The observer operates the operation unit 207 to adjust the display position and the display magnification of the waveform (S50). Then, the observer determines the presence or absence of a dent by checking the presence or absence of a periodic strong peak as shown in FIG. 11 from the displayed waveform.

Thereafter, the flow returns to S44 when checking another hard disk, and ends when not checking (S51).

Next, the details of the cutout will be described with reference to FIG. FIG. 17 is a view showing a cutting process.

The inspection apparatus 201 starts taking in data in response to an instruction from the observer to start inputting. The inspection device 201 generates digital data in the PCM format from the captured data and stores the digital data in the buffer 203. At the same time, the inspection apparatus 201 calculates the average value of the noise power from the head of the PCM data accumulated in the buffer 203 by the waveform data conversion unit 204 at regular intervals (for example, about 0.1 second). Judge the state of the data according to.

The data states are A to B, B to C, C
To D. A is a state in which noise is silent, B is a state in which noise is equal to or higher than a predetermined level L1, C is a state in which noise is attenuating, and D is a state in which noise has been attenuated.
The inspection apparatus 201 determines that the state is A during a period from the start of data acquisition to the time when the data exceeds the sound pressure L1 for a certain period of time. Thereafter, when the captured data exceeds the sound pressure L1 for a certain period of time, the inspection apparatus 201 determines that the state is B during the period from that point in time until the data falls below the sound pressure L1. Thereafter, when the captured data falls below the sound pressure L1, the inspection apparatus 201 determines that the state from the time until the data becomes silent is state C. Thereafter, when the captured data becomes silent, the inspection apparatus 201 determines that the state is D. Then, the inspection apparatus 201 terminates the data capture after a lapse of a predetermined time from the time point (time T1) when the state is entered.

After that, the inspection apparatus 201 reads out the data stored in the buffer 203 by the waveform data conversion unit 204, and sets a period of time (approximately 1 second) from the time T1 when the data state becomes D to The dent 103 is cut out as a period in which the presence or absence of the dent 103 should be determined. Then, the inspection device 201 performs Wavelet conversion on the data extracted during the period cut by the Wavelet conversion unit 208.

As described above, in the fourth embodiment, the dent 103
Since the period in which the feature of (1) is strongly exhibited is cut out, the memory capacity required for processing data can be reduced, and the processing time can be shortened. For example, in the fourth embodiment, the data to be processed is about 15 seconds in the third embodiment, while the data to be processed is about 1 second.
Seconds. Therefore, in the fourth embodiment, the memory capacity can be reduced to about 1/15 and the processing time can be reduced to about 1/15 compared to the third embodiment.

<Fifth Embodiment> The first to fourth embodiments are configured so that the observer determines whether or not the dent 103 exists. However, in such a configuration, the judgment may be erroneously made due to individual differences between observers. Therefore, in the fifth embodiment, the inspection device 201 itself automatically
The presence or absence of was analyzed.

The operation of the fifth embodiment will be described below with reference to FIG. FIG. 18 is a flowchart showing the operation of the fifth embodiment.

The observer operates the operation unit 207 to give an input start instruction (S61). Sound device 202
Receives this instruction, receives an output from the contact microphone 1, generates digital data in the PCM format from the output, and transmits it to the buffer 203 (S62). At this time,
The sound device 202 transmits silent data to the buffer 203 until the hard disk 2 starts. The buffer 203 receives the PCM data from the sound device 202 and stores it (S63).

Next, the observer sets the hard disk 2 on the inspection device 201 and operates the operation unit 207 to turn on the power of the hard disk 2 (S64). Thereby, the hard disk 2 starts. The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 completely starts up, operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S65). Thereafter, the disk 6 of the hard disk 2 keeps rotating for a while due to inertia. In the meantime, the inspection device 201 keeps capturing data,
The fetched data is stored in the buffer 203. Thereafter, the disk 6 stops rotating. As a result, the data is silenced. At this point, the inspection apparatus 201 ends the data acquisition.

Thereafter, the waveform data converter 204 of the inspection apparatus 201 reads out the PCM data from the buffer 203, cuts out the area immediately before the stop of the rotation of the hard disk 2 (S66), and transfers the PCM data of the cut out area to the buffer 203. To be stored.

Thereafter, the Wavelet conversion unit 208
The PCM data in the area cut out by the waveform data conversion unit 204 is read out from the buffer 203,
Et conversion is performed to generate PCM data (S67).
The Wavelet conversion unit 208 transmits the PCM data that has been subjected to Wavelet conversion to the buffer 203, and stores the PCM data in the buffer 203. The control unit 206 reads the Wavelet-converted PCM data from the buffer 203 and analyzes the presence or absence of the dent 103 based on the data (S68). The details of the analysis will be described later.

Thereafter, the waveform data conversion unit 204 reads the PCM data subjected to Wavelet conversion from the buffer 203, and generates waveform data based on the data (S69).

The display 205 stores the presence or absence of the dent 103 analyzed by the control unit 206 and the waveform data generated by the waveform data conversion unit 204 in a buffer 203.
And displays them (S70). Thereby, the observer confirms the presence or absence of a dent.

Hereinafter, the flow returns to S64 when checking another hard disk, and ends when not checking (S71).

Next, referring to FIG. 19, FIG. 20, and FIG.
The details of the analysis will be described. 19 is a diagram showing a region cut out according to the fourth embodiment, FIG. 20 is a diagram showing an analysis process, and FIG. 21 is a diagram showing a process A.

The control unit 206 has, for example, 4 kHz and 8 kHz.
Two frequencies like z are selected, and PCM data subjected to Wavelet conversion of the frequencies is read from the buffer 203 (S81). Next, the control unit 206
The processing A shown in FIG. 1 is performed (S82).

That is, the control unit 206 divides the PCM data of two frequencies into a plurality of blocks of about 0.1 seconds each (S91). After that, the control unit 206
Performs an arbitrary operation for each block. For this arbitrary calculation, for example, ((peak level / average level) -3) is preferably used. This is because it is highly possible that a strong noise whose peak level in the block exceeds three times the average level of the block is due to the dent 103. In the fifth embodiment, the square value of ((peak level / average level) -3) is calculated for each block so that the peak level in each block becomes remarkable (S92). . Next, the control unit 206
The sum of each block is calculated (S93). From the above,
Process A ends. Hereinafter, the total value calculated in S93 is referred to as a score.

Thereafter, the control unit 206 sums up the scores for the two frequencies, and, based on the sum, the dent 10
3 is determined (S83). That is, the control unit 20
6 indicates that there is a dent 103 if the total value is larger than a predetermined value, and 10 if the total value is smaller than a predetermined value.
It is determined that 3 does not exist. In the fifth embodiment, the determination may be made based on the correlation between the total value and the waveform, in addition to the determination based on the total value.

As described above, in the fifth embodiment, the inspection apparatus 2
Since 01 itself automatically analyzes the presence or absence of the dent 103, erroneous judgment due to individual differences of observers can be eliminated. Further, since there is no need to display a waveform, the display 205 can be eliminated.
In this case, it is possible to provide a small and lightweight inspection device 201 at low cost.

<Sixth Embodiment> In the above-described fifth embodiment, for example, if the contact microphone moves within the cut-out area, the presence or absence of the dent 103 cannot be determined due to the noise generated thereby. there is a possibility. Therefore, in the sixth embodiment, an analysis is performed by a method different from that of the fifth embodiment, so that a correct determination can be made even in such a case.

The sixth embodiment will be described below with reference to FIGS. 22, 23, and 24. FIG. 22 is a diagram showing a region cut out according to the fourth embodiment, FIG. 23 is a diagram showing an analysis process, and FIG. 24 is a diagram showing a process B process.

The control unit 206 has, for example, 4 kHz and 8 kHz.
Two frequencies like z are selected, and PCM data subjected to Wavelet conversion of the frequencies is read from the buffer 203 (S101). Next, the control unit 206 performs a process B as shown in FIG. 24 (S102).

That is, the control unit 206 calculates a line three times the average level as shown in FIG. 22 for PCM data of two frequencies, and extracts a peak exceeding this line (S111). Thereafter, the control unit 206, for example, defines a function δT using δTx, C, D and E defined below.
The number of peaks having a relationship of x = C (DE) (hereinafter, referred to as a score) is calculated (S112). Note that the above δT
x is the time between any peaks, C is a predetermined constant, D
Is the minus square of X, and E is the minus square of (X-1).

This is because the noise peak due to the dent 103 appears periodically with the rotation of the disk 6 and decelerates due to bearings and air resistance. Therefore, the time between each peak is determined by the function δTx = C (D -E). Therefore, by quantifying the number of consecutive peaks according to this function, the presence or absence of the dent 103 can be determined.

As described above, the process B is completed.

After that, the control unit 206 sums up the scores for the two frequencies, and based on the sum, the dent 1
03 is determined (S93). That is, the control unit 2
06 indicates that there is a dent 103 when the total value is larger than a predetermined value, and the dent 1 when the total value is smaller than a predetermined value.
It is determined that there is no 03. In the sixth embodiment, in addition to the determination based on the total value, the determination may be performed based on the correlation between the total value and the waveform.

As described above, in the sixth embodiment, the dent 103
By using the periodicity of the peak level and the deceleration of the spindle of the hard disk 2,
The presence or absence of the dent 103 can be determined more accurately than the method of the embodiment.

<Seventh Embodiment> The hard disk 2 differs in the material and structure of each part depending on the type. Therefore, the hard disk 2 differs in the intensity of the spindle noise, the manner of attenuating the rotation, the timbre of the noise due to the dent 103, and the like depending on the type. Therefore, in the seventh embodiment, the inspection device 201 holds parameters such as the intensity of spindle noise, the method of attenuating rotation, and the timbre of noise due to the dent 103 according to the type of hard disk. The data was analyzed using parameters according to the type. Thus, in the seventh embodiment, it is possible to determine the presence or absence of the dent 103 on a plurality of types of hard disks.

The seventh embodiment will be described below with reference to FIG. FIG. 25 is a diagram illustrating the configuration of the control unit according to the seventh embodiment.

As shown in the figure, in the seventh embodiment, the control unit 206 is provided with a parameter holding unit 209 for holding parameters used for analysis according to the type of hard disk. The parameters stored in the parameter storage unit 209 include, for example, the intensity of spindle noise for each type of hard disk, the manner of rotation attenuation, the timbre of noise due to the dent 103, the range, position, and calculation of the cutout area. There are a count to be used, a weight for the calculation result, a reference value to be used for determination, and the like.

The operation of the seventh embodiment is almost the same as that of the embodiment shown in FIG. 18, except that the observer specifies the type of the hard disk 2 in S61. Thus, the control unit 206 operates each unit using the parameters stored in the parameter storage unit 209.

As described above, in the seventh embodiment, since the judgment can be made according to the type of the hard disk 2, the accuracy of the analysis can be improved.

<Eighth Embodiment> The first to seventh embodiments are configured so that an observer performs an inspection by the inspection apparatus 201. In such a configuration, for example, when a large number of hard disks 2 are inspected at a factory, every time an observer inspects the hard disks 2, it is necessary to attach a record at that time to a notebook or the like. However, such an approach requires a great deal of effort on the part of the observer. Therefore, in the eighth embodiment, the data of the hard disk 2 inspected by the inspection apparatus 201 is stored so that the observer can arbitrarily output the data. Thus, in the eighth embodiment, it is possible to inspect a large number of hard disks 2 without imposing a great deal of effort on the observer.

The eighth embodiment will be described below with reference to FIGS. 26, 27 and 28. FIG. 26 is a diagram showing the configuration of the control unit of the eighth embodiment, FIG. 27 is a diagram showing an example of data stored in the storage unit, and FIG. 28 is a flowchart showing the operation of the eighth embodiment. is there.

As shown in FIG. 26, in the eighth embodiment,
The control unit 206 includes a storage unit 210 in addition to the parameter holding unit 209 described above.

The operation of the eighth embodiment will be described below.

The observer operates the operation unit 207 to give an instruction to start inputting (S121). Sound device 202
Receives this instruction, receives an output from the contact microphone 1, generates digital data in the PCM format from the output, and transmits it to the buffer 203 (S122). At this time, the sound device 202 transmits silent data to the buffer 203 until the hard disk 2 starts. The buffer 203 includes the sound device 202
PCM data is received from the server and stored (S12).
3).

Next, the observer sets the hard disk 2 on the inspection apparatus 201 and operates the operation unit 207 to turn on the power of the hard disk 2 (S124). Thereby, the hard disk 2 starts. The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 completely starts up, operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S125). Thereafter, the disk 6 of the hard disk 2 keeps rotating for a while due to inertia. In the meantime, the inspection device 201 keeps capturing data,
The fetched data is stored in the buffer 203. Thereafter, the disk 6 stops rotating. As a result, the data is silenced. At this point, the inspection apparatus 201 ends the data acquisition.

Thereafter, the waveform data converter 204 of the inspection apparatus 201 reads out the PCM data from the buffer 203, cuts out the area immediately before the stop of the rotation of the hard disk 2 (S126), and stores the PCM data in the cut out area in the buffer 203. To be stored.

Thereafter, the Wavelet conversion unit 208
The PCM data in the area cut out by the waveform data conversion unit 204 is read out from the buffer 203,
Et conversion is performed to generate PCM data (S12
7). The Wavelet conversion unit 208 outputs the Wavelet
The converted PCM data is transmitted to the buffer 203,
It is stored in the buffer 203. The control unit 206
PCM subjected to Wavelet conversion from buffer 203
The data is read out, and the dent 103 is read based on the data.
Is analyzed (S128).

After that, the waveform data conversion unit 204 reads the Wavelet-converted PCM data from the buffer 203 and generates waveform data based on the data (S129).

The display 205 stores the presence or absence of the dent 103 analyzed by the control unit 206 and the waveform data generated by the waveform data conversion unit 204 in a buffer 203.
And displays them (S130). At this point, the observer may confirm the presence or absence of the dent 103, or may ignore the dent 103 and confirm the presence or absence of the dent 103 in S133 described later.

The control unit 206 checks the hard disk 2
Is stored in the storage unit 210 (S131). The data stored in the storage unit 210 is preferably a combination of a model number, an analysis result, a score, and the like of the hard disk 2, corresponding to the order of inspection (inspection No.), for example, as shown in FIG.

Hereinafter, the flow returns to S124 when checking another hard disk (S132). When the inspection is not performed, the observer operates the operation unit 207 to operate the storage unit 2.
10 is displayed on the display 205 or output to a printing device (not shown) or another terminal (not shown) (S133). As a result, the observer can see the dent 1
Check for 03. Note that the control unit 206 of the inspection device 201 can add a function of processing data. This allows the observer to process the data into any format. It is preferable that the format is a list in the order of inspection.

Thus, the operation is completed.

As described above, in the eighth embodiment, the inspection apparatus 2
01 stores the data of the hard disk 2 inspected, so that the observer can arbitrarily output the data.
A large number of hard disks 2 can be inspected without imposing a great deal of effort on the observer.

<Ninth Embodiment> The ninth embodiment is directed to the sound data (ie, Wavelet) in the original sound state at the time of inspection.
The PCM data (before conversion) is stored in the storage unit 210 so that the observer can later confirm the sound data of the original sound state at the time of the inspection.

The ninth embodiment will be described below with reference to FIGS. 29, 30, and 31. FIG. 29 is a diagram showing the configuration of the ninth embodiment, FIG. 30 is a diagram showing an example of data stored in the storage unit, and FIG. 31 is a flowchart showing the operation of the ninth embodiment.

As shown in FIG. 29, in the ninth embodiment,
A reproducing unit 211 is provided.

The operation of the ninth embodiment will be described below.

The observer operates the operation unit 207 to give an instruction to start inputting (S141). Sound device 202
Receives this instruction, receives an output from the contact microphone 1, generates digital data in the PCM format from the output, and transmits it to the buffer 203 (S142). At this time, the sound device 202 transmits silent data to the buffer 203 until the hard disk 2 starts. The buffer 203 includes the sound device 202
PCM data is received and stored (S14).
3).

Next, the observer sets the hard disk 2 on the inspection device 201 and operates the operation unit 207 to turn on the power of the hard disk 2 (S144). Thereby, the hard disk 2 starts. The observer waits for the hard disk 2 to completely start up, and after the hard disk 2 completely starts up, operates the operation unit 207 to turn off the power of the hard disk 2 and stop the rotation of a motor (not shown) (S145). Thereafter, the disk 6 of the hard disk 2 keeps rotating for a while due to inertia. In the meantime, the inspection device 201 keeps capturing data,
The fetched data is stored in the buffer 203. Thereafter, the disk 6 stops rotating. As a result, the data is silenced. At this point, the inspection apparatus 201 ends the data acquisition.

Thereafter, the waveform data converter 204 of the inspection apparatus 201 reads out the PCM data from the buffer 203, cuts out the area immediately before the rotation stop of the hard disk 2 (S146), and puts the PCM data in the cut out area into the buffer 203. To be stored.

Thereafter, the Wavelet conversion unit 208
The PCM data in the area cut out by the waveform data conversion unit 204 is read out from the buffer 203,
Et conversion is performed to generate PCM data (S14)
7). The Wavelet conversion unit 208 outputs the Wavelet
The converted PCM data is transmitted to the buffer 203,
It is stored in the buffer 203. The control unit 206
PCM subjected to Wavelet conversion from buffer 203
The data is read out, and the dent 103 is read based on the data.
Is analyzed (S148).

After that, the waveform data converter 204 reads the Wavelet-converted PCM data from the buffer 203, and generates waveform data based on the data (S149).

The display 205 stores the presence or absence of the dent 103 analyzed by the control unit 206 and the waveform data generated by the waveform data conversion unit 204 in the buffer 203.
And display them (S150). At this point, the observer may confirm the presence or absence of the dent 103, or may ignore the dent 103 and confirm the presence or absence of the dent 103 in S133 described later.

The control unit 206 checks the hard disk 2
30 (for example, as shown in FIG.
Or a combination of the model number, analysis result, score, etc. of the hard disk 2) and sound (PC before Wavelet conversion)
M data) is stored in the storage unit 210 (S151).

Thereafter, the flow returns to S144 when checking another hard disk (S152). When the inspection is not performed, the observer operates the operation unit 207 to operate the storage unit 2.
10 is displayed on the display 205, output to a printing device (not shown) or another terminal (not shown), and the sound (W
The playback unit 211 plays back the PCM data before the avelet conversion (S153). Thereby, the observer confirms the presence or absence of the dent 103.

Thus, the operation is completed.

As described above, in the ninth embodiment, since the observer can later confirm the sound data of the original sound state at the time of the inspection, the accuracy of the judgment can be improved.

<Tenth Embodiment> In the first to ninth embodiments, the contact microphone 1 is used for detecting the vibration caused by the dent 103.
Is used. However, the contact microphone 1 is expensive. Moreover, the contact microphone 1 may follow the vibration of the hard disk 2 in some cases. In this case, since accurate acoustic data cannot be obtained, careful handling is required. Therefore, here, the 10th inexpensive and careful handling is unnecessary.
Are presented.

In the tenth embodiment, a low-cost optical head, which is widely used in general, is used instead of the contact microphone 1 as the pickup means. And the tenth
In the example, the optical head was attached to the hard disk 2 via a hard rubber that absorbs vibration in the acoustic frequency band of the hard disk 2 (vibration of about 10 Hz or less). Thus, in the tenth embodiment, since the optical head captures the vibration of the hard disk 2 while absorbing the vibration of the hard disk 2 with the hard rubber, the acoustic data of the hard disk 2 can be acquired without following the vibration of the hard disk 2. . Therefore, in the tenth embodiment, it is possible to acquire accurate acoustic data.

The tenth embodiment will be described below with reference to FIGS. 32, 33, and 34. Note that FIG.
33 is a diagram showing a structure of an optical head, and FIG. 34 is a graph showing a gain characteristic of a tenth optical head.

As shown in FIG. 32, in the tenth embodiment, instead of the contact microphone 1, the optical head 1a is attached to the hard disk 2 to detect the vibration caused by the dent 103. Incidentally, such an optical head 1a is generally a CD-
It is used for a ROM reader, a Mini-DISK reader, and the like.

FIG. 33 shows the structure of the optical head 1a. FIG. 33 (a) is a bottom view of the optical head 1a, and FIG. 33 (b) is a side view when FIG. 33 (a) is viewed from the direction of the arrow. In the figure, reference numeral 1b denotes an optical laser pickup unit that irradiates light and detects reflected light thereof.
c is a vertical servo unit for moving the optical laser pickup unit 1b in the vertical direction, 1d is a lens, 1e is vibration in the acoustic frequency band of the hard disk 2 to be inspected (about 10 Hz).
This is a cable for outputting hard rubber that absorbs the following vibrations) and a 1f sound signal to the sound device unit 202 of the inspection apparatus 201. The optical laser pickup unit 1
b has a gain characteristic corresponding to the distance between the lens 1d and the surface of the housing 9. That is, the optical laser pickup unit 1b
In FIG. 34, as shown in FIG. 34, the gain becomes maximum at the time of focusing, and the gain decreases as the focus goes out of focus. Since the optical head 1a desirably supports the entire mechanism with a surface, the optical head 1a is desirably attached to the center of the cover 11 of the hard disk 2.

At the time of the inspection, the observer is required to
a is attached to the hard disk 2 via the hard rubber 1e. Then, the vertical servo 1c is driven so that the gain of the optical laser pickup unit 1b is maximized, and the vertical position of the lens 1d is adjusted. Thus, the optical head 1a can catch the vibration of the surface of the hard disk 2 as a change in gain. Such first
Since the hard rubber 1e compresses the hard rubber 1e to correct the error in the distance between the optical laser pickup unit 1b and the hard disk 2, the embodiment 0 follows the vibration in the acoustic frequency band of the hard disk 2 (vibration of about 10 Hz or less). Disappears. Therefore, in the tenth embodiment, it is possible to acquire accurate acoustic data.

The operation of the tenth embodiment is the same as that of the ninth embodiment.

As described above, in the tenth embodiment, it is possible to acquire accurate acoustic data, and it is possible to eliminate the need for low-cost and careful handling.

<Eleventh Embodiment> The fifth to tenth embodiments will be described.
The program for analyzing the presence or absence of the dent 103 used in the embodiment can be installed on a general computer via a medium. In the eleventh embodiment, a computer in which a program for analyzing the presence or absence of the dent 103 is installed is presented.

The eleventh embodiment will be described below with reference to FIG. FIG. 35 is a diagram showing the configuration of the eleventh embodiment. In the figure, reference numeral 212 denotes a medium (for example, a floppy disk, CD-ROM, DVD, or the like) storing a program for analyzing the presence or absence of the dent 103, and 213 denotes a general computer.

The observer can read the dent 10 through the medium 212.
3 is installed in the computer 213. After that, the observer started the computer 2
13 reads the acoustic data of the hard disk 2 at the time of inspection from the storage device 3b or the storage unit 210. Then, the observer activates a program installed in the computer 213 to automatically analyze the presence or absence of the dent 103 from the acoustic data of the hard disk 2 at the time of the inspection.

As described above, in the eleventh embodiment, the presence or absence of the dent 103 can be automatically analyzed by a general computer.

<Usage Form> In the first to eleventh embodiments, the case where the presence or absence of the dent 103 in the CSS area is particularly described has been described as an example. However, in these embodiments, as shown in FIG. 36, the presence or absence of a flaw can be inspected in areas other than the CSS area by performing the inspection in a known decompression chamber. This is because the air in the chamber is thinned by the decompression chamber, so that the head 101
Is lowered to collide with a scratch on the disk other than the CSS area.

At this time, the observer does not need to perform any special processing on the hard disk 2. This is because the housing 9 of the hard disk 2 is provided with a hole (not shown) for discharging the internal air expanded by the heat during operation to the outside. In addition, this hole is generally a breathing hole (br
The filter is attached to the housing to prevent dust from entering.

The operation will be described below with reference to FIG.
FIG. 36 is a diagram showing an example of a use mode.
0 shows an example in which the embodiment of FIG. In the figure, 2
14 is a decompression chamber, 215 is a vacuum pump, 2
Reference numeral 16 denotes a pipe connecting the vacuum chamber 214 and the vacuum pump 215.

First, the observer mounts the hard disk 2 to be inspected on the inspection device 201 and sets parameters for the inspection using the operation unit 207. Next, the observer puts the inspection device 201 into the vacuum chamber 214 and activates the vacuum pump 215. Thereby, the vacuum pump 2
15 is a pipe 216 and a decompression chamber 214
The air is extracted from the inside, and the operation is stopped when the atmospheric pressure drops to a predetermined value. Next, the observer operates the inspection device 201 by a remote operation unit (not shown). Thereby, the inspection device 201 inspects the hard disk 2 for the presence or absence of a scratch on the disk. When the inspection is completed, the observer moves to the vacuum pump 2
The valve 15 (not shown) is opened, and air is sent into the decompression chamber 214. Thereafter, the observer moves the decompression chamber 21
Then, the inspection apparatus 201 is taken out from Step 4, and the inspection apparatus 201 is set on a computer (not shown). Then, the observer outputs the data stored in the storage unit 210 of the inspection apparatus 201 to a computer, and causes the computer to analyze the presence or absence of a scratch on the disk. At this time, the computer
The presence / absence of a flaw can be inspected for all areas including the SS area, that is, for areas other than the CSS area.

As described above, in the first to eleventh embodiments, the presence or absence of a flaw can be inspected in areas other than the CSS area by performing the inspection in a known decompression chamber.

[0188]

As described above, the present invention detects a flaw (dent) on a CSS area of a disk from vibration transmitted to the housing of the hard disk. Without opening C
A dent made in the SS area can be found.

An inspection apparatus for performing such an inspection amplifies the vibration transmitted to the housing of the hard disk as sound and amplifies the vibration to the outside. Thereby, the observer can easily find a dent made in the CSS area from the sound. Such an inspection device may have a simple configuration because it may include a contact microphone that detects vibration transmitted to the housing by contacting the housing of the hard disk and a control unit that processes a signal from the contact microphone. Can be realized. In particular, the inspection device can reliably detect vibration when the contact microphone is brought into contact with a screw hole provided in the base of the hard disk or a screw tightened in the screw hole.

Further, the inspection apparatus can be configured to include means for converting a signal from the contact microphone into a digital value, and storage means for storing the digitized signal from the contact microphone. This allows the observer to later analyze the signal from the contact microphone.

Further, the inspection apparatus can be configured to include an extracting means for extracting a sound of collision between a head of the hard disk and a dent made in a CSS area of the disk based on a signal from the contact microphone. . This allows the observer to hear only the noise due to the dent, so that the observer is not confused by the noise due to the nick, and thus the dent attached to the CSS area can be more easily found.

Further, the inspection apparatus comprises means for monitoring the status of the hard disk, and turning on or off the power of the hard disk based on the monitored status of the hard disk.
F, means for detecting the presence or absence of noise from the vibration transmitted to the housing of the hard disk, and means for changing the amplification factor of the sound output to the outside based on the state of the power supply of the hard disk and the state of the noise. A configuration can be provided. Thereby, the inspection device can realize the inspection for the presence or absence of a dent with a simple and low-cost configuration.
Further, the inspection apparatus may be configured to include a display unit that notifies an observer of an inspection available timing. This allows the observer to know the testable timing. In particular, the inspection apparatus may be configured to notify that the inspection is possible while the amplification factor is being increased. This allows the inspection apparatus to concentrate on the timing at which the observer should perform the inspection, thereby preventing the observer from missing the inspection timing.

In such an inspection apparatus, when the power of the hard disk is turned on and the state of the hard disk becomes ready, the power of the hard disk is turned off after a predetermined time has elapsed, and after the hard disk has been turned off, it takes a predetermined time. To increase the amplification of the sound output to the outside,
When the noise disappears, the operation can be performed to reduce the amplification factor. Therefore, the inspection apparatus can automatically perform the inspection without making the observer perform a troublesome operation. Further, since the inspection device can operate while monitoring the state of the hard disk,
The hard disk can be surely put into a testable state, and the time required for the test can be minimized.

Further, the inspection apparatus may be provided with a display for displaying vibration transmitted to the housing of the hard disk as a waveform. This allows the observer to visually determine the presence or absence of a dent. For this reason, the observer is less likely to be affected by individual differences between observers and the environment at the time of observation, so that the presence or absence of a dent can be more stably determined.

Further, the inspection apparatus is capable of transmitting the vibrations transmitted to the housing of the hard disk, which have been converted into digital values, into the Wave.
It is possible to adopt a configuration including means for let conversion.
Accordingly, the inspection apparatus performs analysis based on the PCM data subjected to Wavelet transform that represents a temporal characteristic, so that even if noise due to a dent is small, it can represent a waveform having a periodic strong peak. . Therefore, the observer can make a more accurate judgment.

Further, the inspection apparatus can be configured to cut out an area immediately before the stop of the spindle of the disk and analyze a flaw in the CSS area of the disk. Accordingly, the inspection apparatus cuts out and analyzes a period in which the characteristics of the dent are strongly displayed, so that the memory capacity required for processing data can be reduced and the processing time can be reduced. it can.

Further, the inspection apparatus uses the ratio of the average level and the peak level of the acoustic data to calculate the CSS of the disc.
A configuration for analyzing the presence or absence of a flaw in the area can be adopted.
This allows the inspection apparatus to automatically analyze the presence or absence of a dent, thereby eliminating erroneous determination due to individual differences among observers. In addition, since the inspection device does not need to display a waveform, it is possible to eliminate a display. In this case, it is possible to provide a low-cost, small and lightweight inspection device. The inspection apparatus may be configured to analyze the presence or absence of a flaw in the CSS area of the disk by using the periodicity of the peak level in the acoustic data and the deceleration characteristics of the spindle of the hard disk. This allows the inspection device to more accurately determine whether there is a dent.

Further, the inspection apparatus can store a plurality of types of parameters of the hard disk, and can use a parameter corresponding to the type of the hard disk to be inspected to store the CS of the disk.
A configuration for analyzing the presence or absence of a flaw in the S area can be adopted. Accordingly, the inspection apparatus can make a determination according to the type of the hard disk, so that the determination accuracy can be improved.

Further, the inspection apparatus may be configured to store data of a plurality of hard disks and output the data arbitrarily. This allows the observer to inspect a large number of hard disks without much effort.

Further, the inspection apparatus may be provided with means for reproducing acoustic data in the original sound state at the time of the inspection. This allows the observer to later confirm the sound data of the original sound state at the time of the inspection, thereby improving the accuracy of the determination.

Further, the inspection apparatus may be provided with a vibration pickup means for optically detecting vibration transmitted to the housing of the hard disk. This allows
The inspection apparatus can acquire more accurate acoustic data, and can eliminate low-cost and careful handling.

The program to be used for analysis can be installed on a general computer via a medium. Thus, the observer can automatically analyze the presence or absence of a dent with a general computer.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing an example of an embodiment of a hard disk acoustic inspection apparatus according to the present invention.

FIG. 2 is a perspective view showing an example of a configuration of a hard disk.

FIG. 3 is an external perspective view showing an example of a configuration of a hard disk acoustic inspection device of the present invention.

FIG. 4 is a schematic sectional view showing an example of a mounting structure of a contact microphone.

FIG. 5 is an external perspective view showing a modified example of the hard disk acoustic inspection device of the present invention.

FIG. 6 is a time chart showing details of a hard disk acoustic inspection method of the present invention.

FIG. 7 is an explanatory diagram showing a relationship between a dent and the height of a head.

FIG. 8 is a diagram showing a configuration of a second embodiment.

FIG. 9 is a time chart showing a change in vibration.

FIG. 10 is a flowchart showing the operation of the second embodiment.

FIG. 11 is a diagram showing a noise waveform due to a dent.

FIG. 12 is a diagram illustrating a configuration of a third embodiment.

FIG. 13 is a flowchart showing the operation of the third embodiment.

FIG. 14 is a diagram showing a waveform when a dent is small.

FIG. 15 is a waveform chart according to the third embodiment.

FIG. 16 is a flowchart showing the operation of the fourth embodiment.

FIG. 17 is a view showing a step of extracting an area.

FIG. 18 is a flowchart showing the operation of the fifth embodiment.

FIG. 19 is a diagram showing a cut-out area.

FIG. 20 is a diagram showing an analysis process.

FIG. 21 is a diagram showing a process A.

FIG. 22 is a diagram showing an extracted region.

FIG. 23 is a diagram showing an analysis step.

FIG. 24 is a diagram showing a process B.

FIG. 25 is a diagram illustrating a configuration of a control unit according to a seventh embodiment.

FIG. 26 is a diagram illustrating a configuration of a control unit according to an eighth embodiment.

FIG. 27 is a diagram illustrating an example of data stored in a storage unit.

FIG. 28 is a flowchart showing the operation of the eighth embodiment.

FIG. 29 is a diagram showing a configuration of a ninth embodiment.

FIG. 30 is a diagram illustrating an example of data stored in a storage unit.

FIG. 31 is a flowchart showing the operation of the ninth embodiment.

FIG. 32 is a diagram showing a configuration of a tenth embodiment.

FIG. 33 is a diagram showing a structure of an optical head.

FIG. 34 is a graph showing gain characteristics of the optical head.

FIG. 35 is a diagram showing a configuration of an eleventh embodiment.

FIG. 36 is a diagram showing an example of a use mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Contact microphone 2 Hard disk 3 Amplifier 3a A / D converter 3b Storage device 4 Speaker 5 Control device

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-55-12574 (JP, A) JP-A-3-65641 (JP, A) JP-A-9-231502 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) G11B 5/00 G11B 5/84

Claims (19)

(57) [Claims] 1. A hard disk acoustic inspection method comprising: picking up vibration generated when a head of a hard disk collides with a scratch on a disk from vibrations transmitted to a housing of the hard disk to check for a scratch on the disk. . 2. The hard disk acoustic inspection method according to claim 1, wherein the inspection is performed when the drive of the disk is stopped and the disk is rotating by inertia. 3. A hard disk acoustic inspection apparatus comprising means for picking up vibration generated when a head of the hard disk collides with a scratch on the disk from vibrations transmitted to the housing of the hard disk. 4. The hard disk acoustic inspection apparatus according to claim 3, wherein said pickup means is a contact microphone. 5. The hard disk acoustic inspection apparatus according to claim 3, wherein said pickup means is an optical head. 6. The hard disk acoustic inspection apparatus according to claim 3, further comprising: means for amplifying the vibration picked up by the pickup means as sound and outputting the sound to the outside. 7. The hard disk acoustic inspection apparatus according to claim 3, further comprising a display for displaying a vibration picked up by the pickup means as a waveform. 8. The hard disk acoustic inspection apparatus according to claim 3, further comprising means for converting the vibration picked up by the picking up means into a digital value and storing the digital value. 9. The hard disk sound according to claim 8, further comprising means for detecting a sound of collision between the head of the hard disk and a scratch on the disk based on the vibration stored by the storing means. Inspection equipment. 10. The apparatus according to claim 1, wherein said detecting means has a function of controlling a power supply of a hard disk, a function of monitoring a state of vibration, and a function of changing an amplification factor of a sound output to the outside. 10. The hard disk acoustic inspection apparatus according to 9. 11. The hard disk acoustic inspection apparatus according to claim 9, wherein said detecting means has a function of notifying an observer of an inspection available timing. 12. The vibration converted to a digital value is referred to as Wav.
9. The hard disk acoustic inspection apparatus according to claim 8, further comprising: means for performing elet conversion. 13. The disk drive according to claim 1, wherein the detecting unit cuts out a region immediately before the stop of the rotation of the disk based on the vibration stored in the storage unit and analyzes a flaw in a CSS area of the disk. Item 10. A hard disk acoustic inspection device according to item 9. 14. The hard disk acoustic inspection apparatus according to claim 9, wherein said detecting means analyzes presence / absence of a scratch on the disk by using a ratio between an average level and a peak level of the audio data. 15. The hard disk sound according to claim 9, wherein said detection means analyzes presence / absence of a scratch on the disk using a periodicity of a peak level in the audio data and a deceleration characteristic of a spindle of the hard disk. Inspection equipment. 16. The apparatus according to claim 9, wherein said detecting means can store a plurality of types of parameters of the hard disk, and analyze presence / absence of scratches on the disk using parameters corresponding to the type of the hard disk to be inspected. A hard disk acoustic inspection device as described. 17. The hard disk acoustic inspection apparatus according to claim 3, further comprising means for storing acoustic data in a state of an original sound at the time of inspection. 18. Analyzing the presence / absence of a scratch on a disk using a ratio of an average level to a peak level of acoustic data based on vibration transmitted to a housing of a hard disk, or periodicity of a peak level in acoustic data. A program medium for storing a program for analyzing the presence or absence of a scratch on a disk using a deceleration characteristic of a spindle of a hard disk. 19. The hard disk acoustic inspection method according to claim 1, wherein the inspection is performed in a reduced pressure chamber.