JPH0384703A - Head for magnetic disk device - Google Patents

Abstract

PURPOSE:To reduce the influence of noise from an adjacent track and to attain high density magnetic recording by providing a 1st element applying data read/ write to/from an even numbered track and a 2nd element applying data read/ write to/from an odd numbered track with a magnetic gap not in parallel with the magnetic gap of the 1st element. CONSTITUTION:A 1st electromagnetic conversion element 21 applying data read/write to/from the even numbered track of a disk and a 2nd electromagnetic conversion element 22 applying data read/write to/from the odd numbered track of the disk having a magnetic gap 22a not in parallel with the magnetic gap 21a of the 1st electromagnetic conversion element 21 are provided. That is, the magnetizing direction of the 1st electromagnetic conversion element 21 and the magnetizing direction of the 2nd electromagnetic conversion element 22 are made different. Thus, the influence of noise from adjacent tracks is less and the head capable of high density magnetic recording is obtained.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a head for a magnetic disk drive, more specifically, relates to a head for a magnetic disk drive in which a slider is provided with two electromagnetic transducer elements, which is less affected by noise from adjacent tracks and has high performance. A first electromagnetic transducer element that reads/writes data to even-numbered tracks of a disk; A second electromagnetic transducer is provided, which has a magnetic gap that is not parallel to the magnetic gap of the first electromagnetic transducer, and reads/writes data to/from odd-numbered tracks of the disk.

[Industrial Field of Application] The present invention relates to a head for a magnetic disk device, and more particularly to a head for a magnetic disk device in which a slider is provided with two electromagnetic transducer elements.

In recent years, as the speed and capacity of magnetic disk devices have increased (high-density magnetic recording), it has become difficult to ensure a high signal-to-noise ratio.

Therefore, there is a need for a magnetic disk device that can obtain a sufficient signal-to-noise ratio to ensure the reliability of recorded data.

[Prior Art j Next, a conventional example will be explained using the drawings. FIG. 9 is a configuration diagram of the main parts of a conventional magnetic disk drive, FIG. 10 is a configuration diagram of the main parts of the actuator in FIG. 9, and FIG. 11 is an explanatory diagram of the magnetic disk facing surface of the head in FIG. 9. be.

In these figures, 1 is a base, and 2 is a spindle attached to a spindle motor (not shown) provided on the base 1. The spindle 2 has a magnetic disk 3
A plurality of magnetic disks (three in this figure) are attached, and the magnetic disk 3 is driven by a spindle motor to rotate at a constant speed (for example, 3600 rpm). A head 4 is provided facing each disk surface of each magnetic disk 3 and reads/writes data to/from the magnetic disk 3. The head 4 includes a first electromagnetic transducer 4a that reads/writes data to even-numbered tracks of the magnetic disk 3, and a second electromagnetic conversion element 4a that reads/writes data to odd-numbered tracks of the magnetic disk 3. An electromagnetic conversion element 4b is provided. The magnetic gap of the first electromagnetic transducer 4a and the magnetic gap of the second electromagnetic transducer 4b are provided in parallel.

However, in general, only one of the two electromagnetic transducers performs reading/writing, and the other does not.

Reference numeral 5 denotes an actuator that causes each head 4 to seek to a target track on the magnetic disk 3.

The head 4 is attached to the tip of a gimbal spring 6, and the base end of the gimbal spring 6 is screwed to the head arm 8 using a screw 7.

The head arm 8 is stacked with a spacer 9 in between, and the screw 1
0 and the nut 11, it is magnetized.

A driving coil 12 is attached to the head arm 8 magnetized in this manner.

A yoke 13 is provided on the base 1 and has an inner yoke 13a and an outer yoke 13b. A magnet 14 magnetized in the vertical direction in FIG. 9 is fixed to the inner wall surface of the outer yoke 13b, and the coil 12 is located within the magnetic gap between the magnet 14 and the inner yoke 13a. This forms a moving coil type force motor, which serves as a drive source for the seek system. The seek of the head 4 is performed by a control circuit (not shown) passing current through the coil 12 and moving the actuator 5 in the direction of the arrow in FIG.

[Problems to be Solved by the Invention] In the conventional example with the above configuration, reading/writing data to/from the disk surface of each magnetic disk 3 is performed by the head 4.
Since the magnetization is performed using the first or second electromagnetic transducer elements 4a and 4b provided in the tracks, the magnetization direction is the same in each track.

Therefore, as shown in FIG. 12, when a phenomenon such as offset write due to off-track or seek-related vibration occurs, the noise voltage from the adjacent track increases. and,
As shown in Fig. 13, when off-track occurs, the SN
There are problems in that the ratio deteriorates, the off-track margin (OTM; the lower limit of the S/N ratio required to guarantee errors) is small, and read errors occur.

Furthermore, if the S/N ratio is poor and read errors occur, there is also the problem that high-density magnetic recording cannot be performed.

The present invention has been made in view of the above problems, and its purpose is to provide a head for a magnetic disk device that is less affected by noise from adjacent tracks, can obtain a high S/N ratio, and is capable of high-density magnetic recording. It is about providing.

[Means for Solving the Problems] FIG. 1 is a diagram showing the principle of the present invention. In the figure, 20 is the head of the present invention. Reference numeral 21 denotes a first electromagnetic transducer that is provided in the head 20 and reads/writes data to even-numbered tracks on the disk;
0, has a magnetic gap 22g that is not parallel to the magnetic gap 21a of the first electromagnetic transducer 21, and is a second electromagnetic transducer that reads/writes data to odd-numbered tracks of the disk.

[Function] In the head 20 of the magnetic disk device shown in FIG.
The magnetic gap 21a of the first electromagnetic transducer 21 reads/writes data to even-numbered tracks of the disk. Furthermore, the magnetic gap 22 of the second electromagnetic transducer 22
a is for reading data from odd-numbered tracks on the disk.
Do light.

At this time, the magnetization direction of the first electromagnetic transducer 21 and the magnetization direction of the second electromagnetic transducer 22 are different.

[Example] Next, an example of the present invention will be described with reference to the drawings. 2 is an explanatory diagram of the head in FIG. 3, which is a configuration diagram of the main parts of a magnetic disk device according to an embodiment of the present invention; FIG. 4 is a configuration diagram of the main parts of the actuator in FIG. 3, and FIG. 5 is an explanatory diagram of the magnetization direction of each track of the magnetic disk when data is read/written by the head in FIG. 2.
6 is a diagram illustrating the relationship between θ in FIG. 2 and the noise voltage from the adjacent track, FIG. 7 is a diagram illustrating the relationship between the off-track amount and the noise voltage from the adjacent track in this embodiment, FIG. 8 is a diagram illustrating the relationship between the off-track amount and the SN ratio in this embodiment.

First, the configuration of this embodiment will be explained using FIGS. 2 to 4. In these figures, 31 is a base, and 32 is a spindle attached to a spindle motor (not shown) provided on the base 31. The spindle 32 has
A plurality of magnetic disks 33 (three in this figure) are attached, and the magnetic disks 33 are driven by a spindle motor to rotate at a constant speed (for example, 3600 rpm). A head 34 is provided facing each disk surface of each magnetic disk 33 and reads/writes data to/from the magnetic disk 33 . The head 34 includes a first electromagnetic transducer 34a that reads/writes data to even-numbered tracks of the magnetic disk 33, and a second electromagnetic transducer 34a that reads/writes data to odd-numbered tracks of the magnetic disk 33. Electromagnetic conversion element 34b
and is provided. An angle θ is provided between the magnetic gap 34c of the first electromagnetic transducer 34a and the magnetic gap 34d of the second electromagnetic transducer 34b (see FIG. 2).

35 is an actuator that causes each head 34 to seek to a target track on the magnetic disk 33. head 3
4 is attached to the tip of the gimbal spring 36, and the proximal end of the gimbal spring 36 is further screwed to the head arm 38 using a screw 37. head arm 38
are laminated with a spacer 39 in between, and a screw 40 and a nut 4
1 and is magnetized.

A driving coil 42 is attached to the head arm 38 magnetized in this manner.

A yoke 43 is provided on the base 31 and has an inner yoke 43a and an outer yoke 43b. A magnet 44 magnetized in the vertical direction in FIG. 3 is fixed to the inner wall surface of the outer yoke 43b, and the coil 42 is located within the magnetic gap between the magnet 44 and the inner yoke 43a. This forms a moving coil-type force smoke, which serves as a drive source for the seek system. The seek of the head 34 is performed by a control circuit (not shown) passing current through the coil 42 and moving the actuator 35 in the direction of the arrow in FIG. 3.

When data is recorded on the magnetic disk 33 by a magnetic disk device having such a configuration, the magnetization directions of adjacent tracks differ by an angle of θ, as shown in FIG.

Here, FIG. 6 shows the relationship between θ and the noise voltage from adjacent tracks. As can be seen from this figure, the larger θ becomes, the smaller the noise voltage from adjacent tracks becomes.

Therefore, when a phenomenon such as an offset write due to off-track or seek-related vibration occurs, the noise voltage from the adjacent track is reduced compared to the conventional example, as shown in FIG. As shown in Figure 8, even if off-track occurs, the S/N ratio changes little and can be maintained at a high level, resulting in an off-track margin (OTM, the lower limit of the S/N ratio required to guarantee errors). is larger, making read errors less likely to occur.

When the S/N ratio is improved in this way and read errors are less likely to occur, high-density magnetic recording can be easily performed.

[Effects of the Invention] As explained above, according to the present invention, a first electromagnetic transducer that reads/writes data to even-numbered tracks of a disk, and a magnetic transducer parallel to the magnetic gap of the first electromagnetic transducer By providing a second electromagnetic transducer that reads/writes data to odd-numbered tracks of the disk, the influence of noise from adjacent tracks is reduced and a high S/N ratio is achieved. Therefore, a head for a magnetic disk device capable of high-density magnetic recording can be realized.

[Brief explanation of drawings]

FIG. 1 is a diagram of the principle of the present invention. FIG. 2 is an explanatory diagram of the head in FIG. Figure 4 is a configuration diagram of the main parts of the disk drive, Figure 4 is a diagram of the main parts of the actuator in Figure 3, and Figure 5 is a diagram of each track on the magnetic disk when data is read/written using the head in Figure 2. Figure 6 is a diagram explaining the relationship between θ in Figure 2 and noise voltage from adjacent tracks. Figure 7 is a diagram explaining the relationship between off-track amount and noise voltage from adjacent tracks in this example. FIG. 8 is a diagram explaining the relationship between the off-track amount and the SN ratio of this embodiment. FIG. 9 is a configuration diagram of the main parts of a conventional magnetic disk device. 11 is an explanatory diagram of the magnetic disk facing surface of the head in FIG. 9. FIG. 12 shows the relationship between the off-track amount and the noise voltage from adjacent tracks in a conventional head. An explanatory diagram, Fig. 13, shows the off-track amount and SN in a conventional head.
It is a figure explaining the relationship with a ratio. 1 to 5, 20.34 is a magnetic head, 21.34a is a first electromagnetic conversion element, 21a, 22a, 34c, and 34d are magnetic gaps, 22
．． 34b is a second electromagnetic conversion element.

Claims (1)

[Claims] A first electromagnetic transducer (21) that reads/writes data to even-numbered tracks of the disk, and a magnetic gap (22a) that is not parallel to the magnetic gap (21a) of the first electromagnetic transducer (21). A head for a magnetic disk device, characterized in that the head is provided with a second electromagnetic transducer (22) that reads/writes data to odd-numbered tracks of the disk.