JPH06176336A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To make track density higher by enabling the parallel transfer of data, the realization of high-speed data transfer and the enhancement of positioning accuracy as servo is applied to each of respective recording and reproducing elements. CONSTITUTION:Rail members 201 constituting a slider are connected by piezoelectric elements 202 and are made variable in inter-rail intervals. The multielements/sliders are realized by arraying plural pieces of such constitution. One element to one recording and reproducing circuits are provided within the device and recording and reproducing are simultaneously executed. The dealing with the variable track density is enabled by controlling the piezoelectric elements 202 between the rail members 201.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a magnetic head for recording / reproducing magnetic information, a servo system for positioning the magnetic head, and parallel recording for high-speed data transfer. Regarding the playback method.

[0002]

2. Description of the Related Art Conventionally used magnetic disk devices convert data sent from a host machine as parallel data into serial data and further add an error correction code to make a recording code suitable for magnetic recording. After the modulation, the information was recorded by the magnetic head. Further, when reproducing information, the magnetization information recorded on the recording medium was converted into an electric signal by the magnetic head and the recorded code was reproduced. After that, the data is demodulated into serial data, error correction is performed, and then serial / parallel conversion is performed to output parallel data to a higher-level device. Further, when recording / reproducing information, a magnetic head for recording / reproducing is selected by a head select signal, and recording / reproducing is performed by the magnetic head. Therefore, the information transfer speed at the input / output end of the magnetic head becomes slower than the data transfer speed with the host machine, which is a bottleneck for improving the performance of the magnetic disk device.

One of the means for improving the transfer rate is
It is disclosed in JP-A-2-39226. In this conventional example, parallel data is directly divided into bits, and data is recorded in byte units, and data is simultaneously recorded in byte units on a corresponding medium surface by a magnetic head corresponding to each bit position. According to this method, since there is no parallel / serial conversion, the data transfer rate per head is 1/8 that of the conventional device. In other words, the data transfer rate capability of the disk device can be increased to eight times that of the conventional one. In Japanese Patent Laid-Open No. 1-282703, parallel data is recorded on a corresponding medium surface by a recording-only magnetic head corresponding to each bit position, and the recorded information is read-only on the same slider. The head can read and verify at almost the same time.

[0004]

According to the publicly known examples disclosed above, a method is used in which a magnetic head corresponding to each bit is used to simultaneously record on the corresponding recording medium surface in byte units. However, all of these methods require heads for the number of bits, and since recording is performed on the medium surface corresponding to each bit, the following problems remain.

First, the same number of heads as the number of bits are mounted on one actuator, and recording and reproduction are performed at the same time.
Since servoing cannot be performed for each head, only the servo surface servo method can be used as the servo method. Therefore, there is a problem in that it is not possible to deal with the mechanical tilt of the actuator and the offset for positioning for each head due to temperature. Therefore, there is a problem in increasing the track density from the viewpoint of protecting adjacent tracks.

According to the present invention, the above problems, that is, the mechanical tilt of the actuator and the offset with respect to the positioning for each head due to temperature, are dealt with, the number of sliders and the number of media are reduced, and the apparatus is miniaturized. Is to raise.

[0007]

In order to solve the above problems, a plurality of recording / reproducing elements are mounted on one slider, and recording / reproducing is performed by one slider as a plurality of bits of information as parallel data. Also, each slider is treated as independent data. As a result, the servo method is used as the data surface servo so that the servo can be applied to each head, and two movable portions for positioning are further provided. On the other hand, to reduce the size of the device, the number of sliders is reduced by mounting one slider and a plurality of elements as described above. However, in a swing-type actuator used in a small device, the track interval becomes narrow as the yaw angle increases, so that the influence of adjacent tracks appears. Therefore, the influence of the adjacent track can be reduced by providing means for varying the distance between the respective elements.

[0008]

With the servo system being the data surface servo system, the positioning accuracy can be improved for each head by providing two movable parts for positioning for each head.
Further, in the head having a plurality of sliders mounted with one element, the distance between the respective elements can be made variable, so that the influence of adjacent tracks can be reduced.

Since the rail interval can be controlled, simultaneous tracking of multiple elements using the data surface servo system can be performed, and simultaneous recording / reproduction can also be performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus configuration of an embodiment of the present invention will be described with reference to FIGS. Magnetic disk drive 1 in the present embodiment
00 is at least one magnetic recording medium 101,
At least one or more magnetic heads 102 for recording and reproducing information on a recording medium, a recording / reproducing circuit 103 for performing recording / reproducing by the magnetic heads, and an interface circuit (I / I / I) serving as a gateway for information with a host machine F) 104
A servo control 105 for positioning the magnetic head on a target track and a voice coil motor 106 as a drive unit thereof, and a spindle 1 for mounting a recording medium.
07 and spindle motor 108 for rotating it
And a control circuit 109 for controlling each of them, and is a device for recording and reproducing information from the host machine 110.

Of these embodiments, FIG. 3 shows a more detailed overall structure of a necessary part in the case of parallel information recording / reading and transfer from the magnetic head. The main part for recording / reproducing parallel information is a plurality of recording / reproducing elements 1.
A magnetic head 102 composed of 12 (hereinafter referred to as a slider to distinguish it from a magnetic head having one element)
And a recording / reproducing circuit 103 corresponding to each recording / reproducing element,
A byte data separation / combination circuit 111 for separating and combining the information reproduced in parallel into byte data.

Next, the plural elements 112 used in the embodiment of the present apparatus
FIG. 1 shows a three-dimensional view of an embodiment of a slider 102 on which is mounted. For comparison, a conventional slider (magnetic head) is shown in FIG. In the configuration of the present embodiment, only the rail portion 301 of the conventional slider is taken out to form the rail member 201 of the embodiment. Further, one recording / reproducing element 112 is mounted on the rail member 201. In the conventional slider, the portion 302 connecting the rail portions and the rail portion 30 are connected.
1 has an integrated structure, the rail members 201 are connected by the piezoelectric element 202 in this embodiment. That is, by laminating the rail member 201 via the piezoelectric element, the magnetic head 102 having one slider and a plurality of elements is formed. Further, the slider 102 is bonded to the gimbal 113 and mounted on the device.

Next, regarding the number of piezoelectric elements 202 to which the rail member 201 is connected, it is sufficient to simply connect one or more. However, in order to have the function described later, it is necessary to expand and contract the piezoelectric element 202. In order to suppress the rolling deformation of the rail member 201 due to the expansion and contraction, the piezoelectric element 202 should be set to about three as shown in FIG. Is good. Further, a length measuring sensor 203 is provided to monitor the amount of expansion and contraction of the rail member 201 so that the rail member 201 moves in parallel.

Next, the reason why the rail member 201 is connected by a piezoelectric element will be described.

First, in the conventional disk device, since recording / reproducing is performed at a constant clock frequency, the recording density becomes low on the outer peripheral side, and the device has a large margin with respect to the device specifications. Therefore, on the outer peripheral side, the recording density is increased so that the device has an equal margin at any radial position of the device,
At the same time, means for increasing the storage capacity have been invented. However, with this means, the recording frequency becomes higher toward the outer circumference, and the deterioration of the magnetic characteristics of the magnetic head has a large effect, so that the margin potential on the outer circumference side cannot be effectively used. Therefore, as shown in FIG. 6, the track density is increased toward the outer circumference, and the margin potential is effectively converted into the recording density. Here, the track density is increased, that is, the track pitch is narrowed.

On the other hand, since it is premised that parallel recording / reproducing is performed from the magnetic head 102, that is, a plurality of recording / reproducing elements simultaneously perform recording / reproducing, simultaneous recording is performed at a constant distance from an adjacent element. It is not possible to improve the track density in the reproduction mode. Therefore, the above condition can be satisfied by providing a mechanism for varying the rail member interval.

Another reason is that when a plurality of sliders having a plurality of elements are simultaneously recorded and reproduced, the slider shown in FIG.
As shown in FIG. 5, a position shift (hereinafter referred to as a temperature offset) 115 occurs due to expansion and contraction of the load arm 114 due to temperature change for each actuator. A method for removing this temperature offset will be described here using a slider having three rail members 201 as an example.

Here, the rail members 201 constituting the slider are assigned to 1, 2, 3 and 4, 5, 6. Further, the load arm 114 is connected to the rail members 2 and 5 of the slider 102 via a gimbal 113. now,
When the load arms have different expansion and contraction amounts due to temperature fluctuations, a temperature offset 115 is generated between the rail members 2 and 5. The temperature offset 115 also affects between the rails 1 and 4 and between the rails 3 and 6, but by using the slider structure of this embodiment, the temperature offset can be eliminated by the following procedure example.

Step 1: Positioning is performed on a target track with the rail 2 of the uppermost slider as a reference. Step 2: Adjust the distance between the rail 2 of the uppermost slider and the rail 1 or the rail 2 of the slider mounted on the same load arm by the number of tracks set. In that case, the interval is confirmed while reading the servo information on both the rails 1 and 2. Step 3; Since the positional offset distance between the rail 2 of the slider attached to the load arm different from the load arm to which the uppermost slider is attached and the rail 2 of the uppermost slider is the temperature offset 115, the magnitude thereof is set. The temperature offset can be eliminated by taking into consideration the setting of the distance between the rails 4, 5, 5 and 6. Furthermore, rails 4, 6
Both read servo information and follow the same tracks as rails 1 and 3, respectively. Step 4; Following action is rails 1, 3, 4, 6
In each of the above, the VCM 106 and the piezoelectric element 202 are controlled by the data surface servo.

The above is the case of the three-rail slider,
A multi-rail slider can be constructed by stacking rail members, and in that case, positioning control may be performed in the same manner as described above.

Next, the relationship between the recording / reproducing elements attached to each rail and the servo information at that time will be described with reference to FIGS. 8, 9 and 1.
0, which will be described with reference to FIG.

FIG. 8 shows all the recording / reproducing elements arranged in parallel, and FIG. 9 shows the servo information at that time. The configuration divides one round into sector units, and further divides one sector into a servo information area and a data area. The servo information area is composed of a head mark 401 indicating the head of a sector, address information indicating the track number of each track, and finally offset information for evaluating the amount of displacement from the track.

The problem here is the recording / reproducing element 11.
It is possible to align the two gap positions. The part considering the problem is the installation of the expansion / contraction control piezoelectric element 204 in the rail direction shown in FIG. Thereby, the gap positions on both sides can be aligned with each other with the gap position of the rail member adhered to the gimbal 113 as a reference. The procedure is shown below. Here, the rail members are numbered 1, 2 and 3 as described above.

Step 1; recording / reproducing element 11 of rail member 2
2 and the recording / reproducing element 112 other than the recording / reproducing element of the rail member 2 reproduces the servo information. Step 2: Evaluate the phase difference between the servo information reproduced by the recording / reproducing element of the rail member 2 and the servo information reproduced by the recording / reproducing element other than the rail member 2, and expand / contract the piezoelectric element 204 by a distance corresponding to the phase difference. Let

The positioning method using the servo information of FIG. 9 is performed as follows. First, while the servo information is reproduced by the recording / reproducing element 112 of the rail member 2, the target track, for example, # 100 track is sought. Next, considering the set number of tracks of the rail members 1, 2, 2, and 3, for example, if rail 1 is -10 tracks and rail 3 is +10 tracks, rail 1 is # 90 tracks,
The rail 3 follows the position of the # 110 track.

FIG. 10 shows the recording / reproducing element 112 having an azimuth angle. The servo information in this structure is shown in FIG.
It is shown in FIG. In this case, the recording / reproducing element of the rail member 2 can reproduce the information recorded by the recording / reproducing element of the rail 1, but cannot reproduce the information recorded by the recording / reproducing element of the rail 3. Further, the azimuth loss is large between the recording / reproducing elements on the rails 1 and 3, so that mutual information cannot be reproduced.

The format of the servo information in this case will be compared with FIG. 9 and only different points will be described. First, one track is divided into even-numbered and odd-numbered tracks. Next, the offset information is divided into even-numbered areas and odd-numbered areas. The head mark area and the address information area are shared areas.

The positioning method using the servo information shown in FIG. 11 is performed as follows. First, it is determined that the recording / reproducing element on the rail 1 records / reproduces the odd-numbered tracks, and the recording / reproducing element on the rail 3 records / reproduces the even-numbered tracks. Thus, if the target track is, for example, the # 100 track, the rail 2 is first sought to the target track # 100 track. Next, considering the set number of tracks for rails 1 and 3, for example, if rail 1 is an odd-numbered track of -5 tracks and rail 3 is an even-numbered track of +5 tracks, rail 1 is an odd-numbered track of # 95,
The rail 3 follows the position of the even-numbered track of # 105.

Next, the medium facing surface of the rail member (rail surface)
The processing will be described with reference to FIG. Future magnetic heads will continue to have higher peripheral speeds and lower flying heights and lower loads. Therefore, in order to suppress the levitation force at the medium facing surface at high speed, the rail width 2
05 is narrowed and is provided on both sides to ensure stability against rolling. Further, the rail length is set from the inflow end to the outflow end in order to secure stability against pitching. However, since the piezoelectric element 204 for adjusting the gap position of the recording / reproducing element is on the way, the rail is interrupted at that portion. Further, the inflow end has a tapered flat shape in order to stably hold air.

[0030]

According to the present invention, since simultaneous tracking of multiple elements can be performed and simultaneous recording / reproduction can be performed, high-speed data transfer becomes possible. In addition, the slider rail interval can be made variable, and servo can be applied to each head. That is, the data surface servo system can be used. Therefore, the positioning accuracy can be increased, and as a result, the track density can be increased. Due to this effect,
The capacity of the device can be increased.

On the other hand, since data can be transferred in parallel and recording / reproduction can be performed by a multi-element head, it is possible to reduce the number of recording media even when recording bit-divided byte data, and downsizing the apparatus. Can be done.

Further, since the rail interval of the slider can be made variable, the track density can be increased in the outer peripheral portion of the magnetic disk device. As a result, the capacity of the device can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic head slider of the present invention.

FIG. 2 is a block diagram of a magnetic disk device.

FIG. 3 is a block diagram of a magnetic disk device using the magnetic head slider of the present invention.

FIG. 4 is a perspective view of a conventional magnetic head slider.

FIG. 5 is an explanatory diagram of a magnetic head slider of the present invention.

FIG. 6 is an explanatory diagram of an embodiment of increasing the track density using the magnetic head slider of the present invention.

FIG. 7 is an explanatory diagram of a temperature offset removing method.

FIG. 8 is an explanatory diagram of a first embodiment of a recording / reproducing element arrangement.

9 is an explanatory diagram of a servo information format in the case of the recording / reproducing element arrangement of FIG.

FIG. 10 is an explanatory diagram of a second embodiment of the recording / reproducing element arrangement.

11 is an explanatory diagram of a servo information format in the case of the recording / reproducing element arrangement of FIG.

FIG. 12 is an explanatory diagram of an example of a medium facing surface shape.

[Explanation of symbols]

112 ... Recording / reproducing element, 113 ... Gimbal, 201 ... Rail member, 202 ... Piezoelectric element, 203 ... Length measuring sensor, 2
04 ... Piezoelectric element.

Claims (12)

[Claims] 1. A magnetic recording medium for recording information as a change in magnetization, a magnetic head for making a change in magnetization, a servo system for positioning the magnetic head, and a signal processing circuit system for recording / reproducing information. In a magnetic recording / reproducing apparatus including, a magnetic head comprising a rail member, a flexible member for changing a distance between the rail members, and a recording / reproducing element provided at an air outflow end of a medium facing surface of the rail is mounted. A magnetic recording / reproducing apparatus characterized by the above. 2. The magnetic head as claimed in claim 1, wherein a plurality of rail members per slider, at least one flexible member and at least one per rail.
A magnetic recording / reproducing apparatus having at least one recording / reproducing element. 3. The recording / reproducing element according to claim 1,
A magnetic recording / reproducing device which is an element having a recording or reproducing function or both functions. 4. The magnetic recording / reproducing apparatus according to claim 1, wherein a piezoelectric element is used as a member connecting the rails. 5. A magnetic recording / reproducing apparatus according to claim 1, wherein the recording / reproducing element mounted on each rail has the azimuth angle between adjacent rails. 6. A magnetic recording device comprising, as movable parts for performing positioning control, two types of actuators, that is, an actuator that operates the entire slider and a piezoelectric actuator that changes a rail interval based on one rail fixed to a gimbal arm. Playback device. 7. The magnetic recording / reproducing apparatus according to claim 6, wherein the piezoelectric actuator between the rails operates so as to hold an arbitrarily set number of tracks between the rails. 8. A magnetic recording / reproducing apparatus wherein the track density is changed for each radius. 9. A magnetic recording / reproducing apparatus according to claim 1, wherein a plurality of elements record / reproduce simultaneously. 10. In a magnetic head having an even number of recording / reproducing elements mounted on one slider, a rail fixed to a gimbal arm accesses only even tracks, and an outer rail adjacent to the fixed rail has only odd tracks. A magnetic recording / reproducing apparatus having a positioning mechanism for accessing a magnetic disk. 11. The magnetic recording / reproducing apparatus according to claim 10, wherein tracks accessed by a rail fixed to the gimbal arm are assigned to even-numbered tracks or odd-numbered tracks. 12. A contact detection function for detecting a contact by detecting an electromotive force of a piezoelectric element between the rails due to vibration when the rail comes into contact with a magnetic recording medium, and detecting the electromotive force. A magnetic recording / reproducing apparatus characterized by being provided.