JP2000076634A - Contact test device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable contact between a slider and a disk to be evaluated with high precision by taking the signal of a vibration detecting element outside the spindle while the lowering of an S/N is suppressed. SOLUTION: The device is provided with a holding mechanism 2 for holding a disk 1 and integrally rotating it; a slider 4 with a head loaded which performs recording and/or reproducing for the disk; an arm 5 which is moved in a prescribed direction with the slider 4 held; at least one vibration detecting element 101 for detecting contact between the slider 4, which is loaded on the disk 1 or the holding mechanism 2, and the disk 1; a signal amplifying means 200 which amplifies the signal of the vibration detecting element 101 and which is loaded on the holding mechanism 2; and signal transmitting means 11, 12 for transmitting such an output signal of the element 101 as amplified by the signal amplifying means 200. Consequently, a weak signal of the vibration detecting element 101 does not go through the signal transmitting means 11, 12 while a fully amplified signal goes through the signal transmitting means 11, 12, thereby enabling a high precision to be maintained for the contact test.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slider and disk contact inspection apparatus used for evaluating mechanical characteristics and tribological characteristics of a slider and a disk of a disk device.

[0002]

2. Description of the Related Art For example, in a magnetic disk device for magnetically recording and / or reproducing information as a disk device, a slider on which a magnetic head is mounted is floated at substantially constant intervals on a recording / reproducing surface of a magnetic disk. Recording and reproducing information. In the development and manufacture of such magnetic disk devices, various inspection devices are used to guarantee the mechanical characteristics and tribological characteristics of the slider and the magnetic disk. A contact inspection device between a slider and a magnetic disk is one of them.

As a device for inspecting the contact between a slider and a magnetic disk, a technique described in Japanese Patent Application Laid-Open No. Hei 8-297816 is known. FIG. 6 shows an example of a conventionally used contact inspection device between a slider and a magnetic disk. A magnetic disk 1 as a recording medium, a spindle 2 for holding and rotating the magnetic disk 1, a spindle drive circuit 3 as a spindle driving means for driving the spindle 2, and a magnetic head for recording and reproducing on the magnetic disk 1 (not shown) 4), and an arm 5 supporting the slider 4
A voice coil motor 6 as an actuator for moving the arm 5 and moving the slider 4 attached to the arm 5 in the radial direction of the magnetic disk 1, an actuator driving circuit 7 as driving means for the voice coil motor 6, An AE (acoustic elastic wave) sensor 100 as a micro-vibration detecting element mounted on the disk 1, a slip ring 11 and a brush 12 as signal transmission means of an output signal of the AE sensor 100, and an output signal of the AE sensor 100 is amplified. A high-band amplifier 8 as a signal amplifying means, a filter 9 for extracting a frequency component necessary for contact inspection from an output signal of the high-band amplifier 8, and an oscilloscope 10 as a display means for displaying an output signal of the filter 9. It is composed of

The operation will be described below. The magnetic disk 1 is rotated at a high speed of, for example, 5,400 rpm by the spindle 2. The slider 4 has an air bearing surface on the surface facing the recording / reproducing surface of the magnetic disk 1.
Float at substantially constant intervals. Voice coil motor 6
Moves the slider 5 in the radial direction of the magnetic disk 1 by moving the arm 5. As described above, the slider 4 normally floats with respect to the magnetic disk 1. That is, the slider 4 and the magnetic disk 1 are in a non-contact state. However, the slider 4 often comes into contact with the magnetic disk 1 due to the start and stop of the rotation of the magnetic disk 1, the attachment of dust to the slider 4, and the shape defect of the slider 4 and the magnetic disk 1.

In the conventional example shown in FIG. 6, an AE sensor 100 as a micro-vibration detecting element is mounted on the disk 1, and an AE generated by the contact between the slider 4 and the magnetic disk 1, that is, an acoustic elastic wave is detected. I do. The detected output signal from the AE sensor 100 is output to the high-bandwidth amplifier 8.
To an observable level. Further, the noise component is removed by the filter 9 and observed by the oscilloscope 10. A observed with the oscilloscope 10
From the waveform of the output signal of the E sensor 100, the strength of the contact, the duration of the contact, and the like can be evaluated.

[0006]

In the above-described contact inspection apparatus, the AE sensor 100 is mounted on the disk 1, and rotates together with the disk 1. Therefore, it is necessary to transmit a signal from the rotating body to the outside. One example of signal transmission means for realizing this is the slip ring 11.
And the brush 12, the output signal of the AE sensor 100 is very weak, for example, several tens of microvolts, so the S / N decreases when passing through these signal transmission means, and the accuracy of the contact inspection also increases. Had declined.

Accordingly, an object of the present invention is to make it possible to evaluate the contact between the slider and the disk with high accuracy by extracting the signal of the vibration detecting element to the outside of the holding mechanism while suppressing a decrease in S / N. The object of the present invention is to provide a contact inspection device capable of performing the following.

[0008]

According to a first aspect of the present invention, there is provided a contact inspection apparatus, comprising: a holding mechanism for holding a disk and rotating integrally with the disk; and recording and / or reproducing data on and from the disk. A slider mounted with a head for performing the operation, an arm which is moved in a predetermined direction while supporting the slider, at least one vibration detecting element mounted on the disk or the holding mechanism for detecting contact between the slider and the disk, and There is provided a signal amplifying means mounted to amplify a signal of the vibration detecting element, and a signal transmitting means for transmitting an output signal of the vibration detecting element amplified by the signal amplifying means.

As described above, there are provided signal amplifying means mounted on the holding mechanism for amplifying the signal of the vibration detecting element, and signal transmitting means for transmitting the output signal of the vibration detecting element amplified by the signal amplifying means. Therefore, a sufficiently amplified signal passes without passing a weak signal of the vibration detecting element through the signal transmission means. For this reason, it is possible to suppress a decrease in S / N due to signal transmission, and to keep the accuracy of the contact inspection high.

According to a second aspect of the present invention, there is provided a contact inspection apparatus, wherein a holding mechanism for holding a disk and rotating integrally therewith, a slider having a head for recording and / or reproducing data on and from the disk, and a predetermined state with the slider being supported. An arm moved in the direction, at least one vibration detection element mounted on the disk or the holding mechanism for detecting contact between the slider and the disk, and impedance conversion means mounted on the holding mechanism for converting the output impedance of the vibration detection element. Signal transmitting means for transmitting the output signal of the vibration detecting element converted by the impedance converting means.

As described above, there are provided the impedance conversion means mounted on the holding mechanism for converting the output impedance of the vibration detection element, and the signal transmission means for transmitting the output signal of the vibration detection element converted by the impedance conversion means. Therefore, the impedance of the signal transmission means and the output impedance of the vibration detecting element can be matched. For this reason, transmission over a wide frequency range becomes possible, and the accuracy of the contact inspection can be kept high as in the first aspect.

According to a third aspect of the present invention, there is provided a contact inspection apparatus.
(2) In the above (2), the signal transmission means comprises a rotating conductor fixed to the holding mechanism and rotating with the rotation of the holding mechanism, and a contact conductor contacting the rotating conductor with the rotation of the holding mechanism. The power of the detection element and the signal amplifying means or the impedance converting means is transmitted through the contact between the rotating conductor and the contact conductor.

As described above, the power of the vibration detecting element and the signal amplifying means or the impedance converting means is transmitted through the contact between the rotating conductor and the contact conductor.
There is no need to provide a new power supply means, and the cost of the apparatus can be reduced. According to a fourth aspect of the present invention, in the first or second aspect, the signal transmission means is fixed to the holding mechanism, rotates with the rotation of the holding mechanism, and transmits a signal to the air. A signal receiver for receiving the signal converted by the transmitter,
The power of the vibration detecting element and the signal amplifying means or the impedance converting means is transmitted via non-contact transmission and reception between the signal transmitter and the signal receiver. As described above, the power of the vibration detecting element and the power of the signal amplifying means or the impedance converting means are transmitted via the non-contact transmission and reception between the signal transmitter and the signal receiver. Can be

According to a fifth aspect of the present invention, there is provided a contact inspection apparatus.
In or 2, the battery for supplying power to the signal amplifying means or the impedance converting means was mounted on the holding mechanism. As described above, since the battery for supplying power to the signal amplifying means or the impedance converting means is mounted on the holding mechanism, the same effect as in claim 3 can be obtained, and the means for supplying the output signal of the vibration detecting element to power supply As compared with the case where transmission is performed using the same transmission means, power supply noise is not superimposed on the signal.

According to a sixth aspect of the present invention, there is provided a contact inspection apparatus.
In or 2, the field effect transistor is used in the input stage of the signal amplifying means or the impedance converting means.
As described above, since the field effect transistor is used in the input stage of the signal amplifying means or the impedance converting means, it is possible to perform impedance matching with a vibration detecting element having an output impedance as high as 10 kΩ or more.

[0016] The contact inspection apparatus according to claim 7 is the first aspect of the invention.
In (2), the input impedance of the signal amplification means or the impedance conversion means is 10 kΩ or more. As described above, when the input impedance of the signal amplifying means or the impedance converting means is 10 kΩ or more, the same effect as that of the sixth aspect can be obtained.

According to another aspect of the present invention, there is provided a contact inspection device which holds a disk and rotates integrally therewith, a slider having a head for recording and / or reproducing data on and from the disk, and a predetermined state in which the slider is supported. Arm that is moved in the direction, at least one vibration detecting element mounted on the disk or the holding mechanism for detecting contact between the slider and the disk, and a vibration detecting unit of the vibration detecting element biasing the disk or the holding mechanism with a constant force. Elastic body.

As described above, since the elastic body which urges the vibration detecting section of the vibration detecting element against the disk or the holding mechanism with a constant force is provided, the contact state between the disk or the holding mechanism and the vibration detecting section of the vibration detecting element is provided. Is kept constant, it is possible to keep the accuracy of the contact inspection high. A contact inspection device according to a ninth aspect of the present invention provides a contact inspection device that holds a disk and integrally rotates the disk, a slider equipped with a head that performs recording and / or reproduction on the disk, and moves the slider in a predetermined direction while supporting the slider. Arm, at least one vibration detecting element for detecting contact between the slider and the disk, and an acoustic shielding member disposed between the disk and the holding mechanism for shielding vibration from the holding mechanism to the disk.

As described above, since the acoustic shielding member is provided between the disk and the holding mechanism and shields the vibration from the holding mechanism to the disk, the vibration generated by means other than the contact between the slider and the disk is detected by the vibration detecting element. , And the accuracy of the contact inspection between the slider and the disk can be kept high.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a contact inspection device according to a first embodiment of the present invention. In FIG. 1, the same reference numerals are given to portions corresponding to FIG.
In FIG. 1, reference numeral 1 denotes a magnetic disk as a disk serving as a recording medium, 2 denotes a spindle as an example of a holding mechanism for holding and rotating the magnetic disk 1 integrally, 3 denotes spindle driving means for driving the spindle 2, and 4 denotes A slider on which a magnetic head for recording and / or reproducing data on and from the magnetic disk 1 is mounted, 5 is an arm which is moved in a predetermined direction while supporting the slider 4, and 6 is an actuator which moves the slider 4 in a radial direction of the magnetic disk 1. Reference numeral 7 denotes an actuator drive circuit as a driving unit of the voice coil motor 6; 101, an AE sensor mounted on the magnetic disk 1 and serving as a vibration detecting element for detecting contact between the slider 4 and the magnetic disk 1; A
The E sensor 101 is a sensor that can capture very small vibrations made of, for example, PZT.
Reference numeral 200 denotes a high band amplifier (signal amplifying unit) as a unit for amplifying the output signal of the AE sensor 101. This high-band amplifier 200 is mounted on the spindle 2. 20
1 is a power supply for supplying power to the high-band amplifier 200, 9 is a filter for extracting a frequency component necessary for contact inspection from an output signal of the high-band amplifier 200, and 10 is an oscilloscope as a display means for displaying an output signal of the filter. .

Further, there is provided a signal transmitting means for transmitting the output signal of the AE sensor 101 amplified by the high band amplifier 200. The signal transmission means comprises a rotating conductor fixed to the spindle 2 and rotating with the rotation of the spindle 1 and a contact conductor contacting the rotating conductor with the rotation of the spindle 2. The signal and the power of the high band amplifier 200 are transmitted by the power supply 201 through the contact between the rotating conductor and the contact conductor. 11 is a slip ring as an example of a rotating conductor,
Reference numeral 12 denotes a brush as an example of a contact conductor.

More specifically, the magnetic disk 1
Is fixed to the spindle 2 by, for example, screwing. A DC servomotor is used as a motor for the spindle 2, and the magnetic disk 1 can be driven at a constant rotation speed from 0 rpm to 10,000 rpm or more. A fluid bearing is used for a bearing portion of the spindle 2. A slider 4 on which a magnetic head (not shown) is mounted is attached to the arm 5. Slider 4
An air bearing surface is formed on the surface of the magnetic disk 1 facing the recording / reproducing surface by machining or etching. The air bearing surface of the slider 4 is pressed by the arm 5 against the recording / reproducing surface of the magnetic disk 1 with a constant load of, for example, 30 mN. Slider 4
As the magnetic disk 1 rotates, pressure is generated on the air bearing surface and the magnetic disk 1 flies above the magnetic disk 1.
The arm 5 is attached to a voice coil motor 6 as an actuator.
Rotate around the axis. Thus, the slider 4 attached to the arm 5 moves in the radial direction of the magnetic disk 1. On the recording / reproducing surface of the magnetic disk 1, an AE sensor 101 as a micro vibration detecting element is mounted.

Next, the operation of the contact inspection device will be described. When the slider 4 comes into contact with the magnetic disk 1 for some reason, AE, that is, an acoustic elastic wave is generated at the contact point. The AE sensor 101 converts the AE, that is, the acoustic elastic wave into an electric signal. AE sensor 1
The output signal 01 is first amplified to a level sufficient for transmission by the high-bandwidth amplifier 200 mounted on the spindle 2. The power supply 201 of the high-band amplifier is a DC 15 V
Power supply. The output signal of the high-band amplifier 200 is guided to the slip ring 11 and the brush 12 as signal transmission means and taken out. The signal taken out is
Only the frequency to be observed is extracted by the filter 9. The output signal from the AE sensor 101 that has passed through the filter 9 is observed by an oscilloscope 10 as a display unit. From the signal waveform observed by the oscilloscope 10, the strength of the contact between the slider 4 and the magnetic disk 1, the duration of the contact, and the like can be known.

Here, the case where the AE sensor 101 is used as the microvibration detecting element has been described. However, any element capable of detecting microvibration due to contact between the slider 4 and the magnetic disk 1 may be used. It can also be used. Also, the case where only one AE sensor is used has been described, but a plurality of AE sensors may be mounted on the magnetic disk 1. However, in that case, a high-band amplifier is also equipped with a plurality of channels. In this embodiment,
Although the description has been given of the example in which the fluid bearing is used as the bearing portion of the spindle 2, when a contact type bearing such as a ball bearing is used, the vibration is also detected by the AE sensor 101, and the slider 4 is magnetically coupled to the slider 4. S / N of contact detection of disk 1
Is deteriorated. Therefore, the bearing is not limited to the fluid bearing as long as the S / N can be sufficiently secured.

As described above, according to the present embodiment, the weak signal of the AE sensor 101 passes through a sufficiently amplified signal without passing through the slip ring 11 and the brush 12, so that the signal S / N can be suppressed, and the accuracy of the contact inspection can be kept high. A second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram showing a contact inspection device according to a second embodiment of the present invention. A description of the same configuration as in the first embodiment will be omitted.

In the first embodiment, the output signal from the AE sensor 102 mounted on the magnetic disk 1 is extracted to the outside by using the slip ring 11 and the brush 12 as signal transmission means. In the second embodiment, the signal transmission means of the AE sensor 102 mounted on the magnetic disk 1 is fixed to the spindle 2 so as to be able to transmit a signal in a non-contact manner, and is rotated with the rotation of the spindle 2 and transmits the signal. A rotary transformer 13a as an example of a signal transmitter for transmitting in the air, and a fixed transformer 13b as an example of a signal receiver for receiving the signal
And are used.

Further, instead of the high-bandwidth amplifier 200 used in the first embodiment, an impedance converter (impedance conversion means) 202 which converts the output impedance of the AE sensor 102 and is mounted on the spindle 2 is used. . AE sensor 102 and impedance converter 20
2 is supplied from the power supply 210 to the rotary transformer 13.
a and the fixed transformer 13b are transmitted via non-contact transmission / reception. At this time, the power supply 210 is an AC power supply, and a rectifier circuit is provided at a power supply input stage of the impedance converter 202. The frequency characteristics of the rotary transformer 13a and the fixed transformer 13b are closely related to their respective impedances, and the higher the impedance, the more difficult it is for high frequencies to pass. Therefore, the rotary transformer 13a
It is desirable that the impedance of the fixed transformer 13b be reduced. However, when the impedance of the transformer is reduced, the output impedance of the AE sensor 102 as high as several tens of kilohms or more cannot be matched, and the transmission efficiency decreases. Therefore, as shown in the second embodiment, by converting the output impedance of the AE sensor 102 by the impedance converter 202, even if the output is transmitted by the rotary transformer 13a and the fixed transformer 13b, an output sufficient for contact detection is obtained. Can be taken out. In this case, the impedance converter 20
2 is amplified by the high-band amplifier 8. By using the rotating transformer 13a, the fixed transformer 13b, and the impedance converter 202 in this manner, non-contact transmission over a wide frequency range becomes possible, and the accuracy of contact inspection can be kept high. Further, by using a field-effect transistor in the input stage of the impedance converter 202, the output impedance can be as high as 10 kΩ or more.
Impedance matching with the E sensor 102 can be achieved.

In the first embodiment, an impedance converter 202 may be used in place of the high-band amplifier 200, and in the second embodiment, the high-band amplifier 200 may be used instead of the impedance converter 202. You may. A third embodiment of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing a contact inspection device according to a third embodiment of the present invention. The description of the same configuration as the first embodiment and the second embodiment is omitted.

In the first embodiment and the second embodiment, the high-bandwidth amplifier 200 and the impedance converter 20
2, the power is supplied from the power supply 201 or the power supply 210. With such a configuration, for example, the slip ring 11 and the brush 12, the rotary transformer 13a and the fixed transformer 13b Such a means for supplying electric power was required. Further, when the output signal of the AE sensor 103 is transmitted using the same transmission unit, there is a problem that power supply noise is superimposed on the signal.
Therefore, in the third embodiment, the above-described problem can be solved by mounting the battery 203 on the spindle 2 without using an external power supply. Although FIG. 3 shows a state applied to the second embodiment, it may be applied to the first embodiment.

A fourth embodiment of the present invention will be described with reference to FIG. FIG. 4A is a block diagram showing a contact inspection device according to a fourth embodiment of the present invention, and FIG. 4B is an enlarged sectional view of a portion A thereof. Note that, in FIG. 4, the portions corresponding to FIG. 6 are denoted by the same reference numerals. In FIG. 4, reference numeral 1 denotes a magnetic disk as a recording medium disk; 2a, a spindle as an example of a holding mechanism for holding and rotating the magnetic disk 1 integrally; 2b, a clamp member for fixing the magnetic disk 1 to the spindle 2a; Numeral 3 is a spindle driving means for driving a spindle, 4 is a slider on which a magnetic head for recording and / or reproducing data on and from the magnetic disk 1 is mounted, 5 is an arm for supporting the slider 4, and 6 is a slider 4
Voice coil motor as an actuator for moving the magnetic disk 1 in the radial direction of the magnetic disk 1, an actuator driving circuit 7 as a driving means of the voice coil motor, 104
Represents A as a vibration detecting element mounted on the magnetic disk 1.
E sensor. Reference numeral 8 denotes a high-band amplifier as a unit for amplifying the output signal of the AE sensor 104, 9 denotes a filter for extracting a frequency component necessary for contact inspection from the output signal of the high-band amplifier, and 10 denotes a display unit for displaying the output signal of the filter. Oscilloscope.

Numeral 11 is a slip ring as an example of a rotating conductor, 12 is a brush as an example of a contact conductor, 20
Reference numeral 4 denotes a spring as an elastic body that presses the AE sensor 104 against the magnetic disk 1. More specifically, the magnetic disk 1 is fixed to the spindle 2 by the clamp member 2b.
a, for example. Before fixing the magnetic disk 1, the detecting unit 104a of the AE sensor 104
Since 04 is in the natural length state, it is above the upper end surface of the spindle 2a. When the magnetic disk 1 is pressed down by the clamp member 2b to fix the same to the spindle 2a, the spring 204 contracts, and the detection unit 104a of the AE sensor 104 is pressed against the magnetic disk 1 with a constant force.

Since this embodiment is configured as described above, even if the magnetic disk 1 is replaced, A
The contact state between the E sensor 104 and the magnetic disk 1 can be kept constant, and the reproducibility of the contact inspection is improved. Further, since there is no need to use an adhesive or the like, the magnetic disk 1 is not damaged. FIG. 5 shows a fifth embodiment of the present invention.
It will be described based on. FIG. 5 is a block diagram showing a contact inspection device according to a fifth embodiment of the present invention. FIG.
In FIG. 7, the portions corresponding to those in FIG.

In FIG. 5, reference numeral 1 denotes a magnetic disk as a recording medium disk; 2a, a spindle as an example of a holding mechanism for holding and rotating the magnetic disk 1;
Is a clamp member for fixing the magnetic disk 1 to the spindle 2a, 3 is spindle driving means for driving the spindle,
Reference numeral 4 denotes a slider on which a magnetic head for performing recording and / or reproduction on the magnetic disk 1 is mounted. Reference numeral 5 denotes an arm for supporting the slider 4. Reference numeral 6 denotes a voice coil motor as an actuator for moving the slider 4 in the radial direction of the magnetic disk 1. , 7 are an actuator driving circuit as a driving means of the voice coil motor, 105 is an AE sensor as a vibration detecting element mounted on the magnetic disk 1, 8 is a high band amplifier as a means for amplifying an output signal of the AE sensor 105, Reference numeral 9 denotes a filter for extracting a frequency component necessary for contact inspection from an output signal of the high-band amplifier, and reference numeral 10 denotes an oscilloscope as display means for displaying an output signal of the filter.

Numeral 11 is a slip ring as an example of a rotating conductor, 12 is a brush as an example of a contact conductor, 20
Reference numerals 5a and 205b denote silicon rubber as an acoustic shielding member for separating the magnetic disk 1 from the spindle 2a and the clamp member 2b with respect to propagation of vibration. More specifically, the silicone rubber 205a, 205b
If there is no vibration, the vibration generated by the sliding of the slip ring 11 and the brush 12 or the bearing of the spindle 2a is detected by the AE sensor 105 so as to be superimposed on the vibration generated by the contact between the slider 4 and the magnetic disk 1. Therefore, the accuracy of the contact inspection between the slider 4 and the magnetic disk 1 is reduced. Therefore, by adopting the configuration shown in this embodiment, the slip ring 11 and the brush 1
2 is not detected by the AE sensor 105 in a manner superimposed on the vibration generated by the contact between the slider 4 and the magnetic disk 1, and the accuracy of the contact inspection is reduced. Never do. When the magnetic disk 1 is held by the spindle 2a and the clamp member 2b, the silicon rubber 205a,
Since the magnetic disk 205 is provided, the magnetic disk 1 is not damaged. In this embodiment, silicon rubber is used as the sound shielding member. However, any material can be used as long as it can shield sound.

The fourth and fifth embodiments are described in the first to fifth embodiments.
This may be applied to the third embodiment.

[0036]

According to the contact inspection apparatus of the present invention, the signal amplifying means mounted on the holding mechanism for amplifying the signal of the vibration detecting element, and the signal of the vibration detecting element amplified by the signal amplifying means are provided. Since the signal transmission means for transmitting the output signal is provided, a sufficiently amplified signal passes without passing a weak signal of the vibration detecting element through the signal transmission means.
For this reason, it is possible to suppress a decrease in S / N due to signal transmission, and to keep the accuracy of the contact inspection high.

According to the contact inspection apparatus of the second aspect of the present invention, the impedance conversion means mounted on the holding mechanism for converting the output impedance of the vibration detection element, and the output of the vibration detection element converted by the impedance conversion means Signal transmission means for transmitting signals,
The impedance of the signal transmission means and the output impedance of the vibration detection element can be matched. For this reason,
Transmission over a wide frequency range becomes possible, and the accuracy of the contact inspection can be kept high as in the first aspect.

According to the third aspect, the power of the vibration detecting element and the signal amplifying means or the impedance converting means is transmitted through the contact between the rotating conductor and the contact conductor. There is no need to provide
The cost of the device can be reduced. In the fourth aspect, the power of the vibration detecting element and the signal amplifying means or the impedance converting means is transmitted via non-contact transmission / reception between the signal transmitter and the signal receiver. can get.

According to the fifth aspect, a battery for supplying power to the signal amplifying means or the impedance converting means is mounted on the holding mechanism, so that the same effects as those of the third aspect are obtained, and the output signal of the vibration detecting element is supplied to the power supply. The power supply noise is not superimposed on the signal as compared with the case where the transmission is performed using the same transmission means as the means for transmitting. According to the sixth aspect, since the field effect transistor is used in the input stage of the signal amplifying means or the impedance converting means, it is possible to perform impedance matching with a vibration detecting element having an output impedance as high as 10 kΩ or more.

According to the seventh aspect, the same effect as the sixth aspect can be obtained by setting the input impedance of the signal amplifying means or the impedance converting means to 10 kΩ or more. According to the contact inspection device according to the eighth aspect of the present invention, since the vibration detecting unit of the vibration detecting element is provided with the elastic body that urges the disk or the holding mechanism with a constant force,
Since the contact state between the disk or the holding mechanism and the vibration detecting section of the vibration detecting element is always kept constant, it is possible to keep the accuracy of the contact inspection high.

According to the contact inspection apparatus of the ninth aspect of the present invention, the slider and the disk are provided because the sound shielding member is provided between the disk and the holding mechanism and shields the vibration from the holding mechanism to the disk. Vibration generated by means other than the contact of the disk is not detected by the vibration detecting element, so that the accuracy of the contact inspection between the slider and the disk can be kept high.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a contact inspection device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a contact inspection device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a contact inspection device according to a third embodiment of the present invention.

FIG. 4A is a block diagram showing a contact inspection device according to a fourth embodiment of the present invention, and FIG. 4B is an enlarged sectional view of a portion A.

FIG. 5 is a block diagram showing a contact inspection device according to a fifth embodiment of the present invention.

FIG. 6 is a block diagram showing a conventional contact inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic disk 2 Spindle 3 Spindle drive means 4 Slider 5 Arm 6 Actuator 7 Actuator drive means 8 Signal amplifying means 9 Filter 10 Display means 11 Slip ring 12 Brush 13a Rotary transformer 13b Fixed transformer 101-105 AE sensor 200 High band amplifier 201 Power supply 202 Impedance converter 203 Battery 204 Spring 205a, 205b Silicon rubber

Claims (9)

[Claims] 1. A holding mechanism for holding and integrally rotating a disk, a slider having a head for recording and / or reproducing data on and from the disk, and an arm which is moved in a predetermined direction while supporting the slider. At least one vibration detection element mounted on the disk or holding mechanism for detecting contact between the slider and the disk; signal amplification means mounted on the holding mechanism for amplifying a signal of the vibration detection element; A signal transmission unit that transmits an output signal of the vibration detection element amplified by the amplification unit. 2. A holding mechanism for holding a disk and rotating integrally therewith, a slider having a head for recording and / or reproducing data on and from the disk, and an arm which is moved in a predetermined direction while supporting the slider. At least one vibration detection element mounted on the disk or holding mechanism for detecting contact between the slider and the disk, and impedance conversion means mounted on the holding mechanism and converting output impedance of the vibration detection element; A signal transmission unit for transmitting an output signal of the vibration detection element converted by the impedance conversion unit. 3. A rotating conductor which is fixed to a holding mechanism and which rotates with the rotation of the holding mechanism, and a contact conductor which contacts the rotating conductor which rotates with the rotation of the holding mechanism. The contact inspection apparatus according to claim 1, wherein the power of the vibration detection element and the signal amplifying means or the impedance conversion means is transmitted via the contact between the rotating conductor and the contact conductor. 4. A signal transmitter which is fixed to a holding mechanism, rotates with the rotation of the holding mechanism, and transmits a signal in the air, and a signal receiver which receives a signal converted by the signal transmitter. The contact according to claim 1 or 2, wherein the power of the vibration detecting element and the signal amplifying means or the impedance converting means is transmitted through non-contact transmission and reception between the signal transmitter and the signal receiver. Inspection equipment. 5. The contact inspection apparatus according to claim 1, wherein a battery for supplying power to the signal amplification unit or the impedance conversion unit is mounted on the holding mechanism. 6. The contact inspection apparatus according to claim 1, wherein a field effect transistor is used in an input stage of the signal amplification means or the impedance conversion means. 7. The contact inspection apparatus according to claim 1, wherein the input impedance of the signal amplification means or the impedance conversion means is 10 kΩ or more. 8. A holding mechanism for holding and rotating integrally with a disk, a slider having a head for recording and / or reproducing data on and from the disk, and an arm which is moved in a predetermined direction while supporting the slider. And at least one vibration detecting element mounted on the disk or the holding mechanism for detecting contact between the slider and the disk, and biasing the vibration detecting section of the vibration detecting element to the disk or the holding mechanism with a constant force. A contact inspection device having an elastic body. 9. A holding mechanism for holding and rotating integrally with a disk, a slider having a head for recording and / or reproducing data on and from the disk, and an arm which is moved in a predetermined direction while supporting the slider. And at least one vibration detecting element for detecting contact between the slider and the disk, and an acoustic shielding member disposed between the disk and the holding mechanism for shielding vibration from the holding mechanism to the disk. Contact inspection device.