JPS63142503A - Magnetic head - Google Patents

Abstract

PURPOSE:To improve the durability of a recording medium by positioning a magnetic gap on a rear end side from the center of a plane part in the running direction of the recording medium, and also, providing a taper or a step difference on the rear end side of the plane part, so that a magnetic gap can be brought into contact with the recording medium by a small load. CONSTITUTION:A tapered part 17 is formed on a rear end side 17 in the running direction of a magnetic recording medium of a magnetic head plane part 14, and a magnetic gap 15 is formed not in the center of the plane part 14 but in the rear end side in the running direction. Also, a front side edge of the plane part 14 is chamfered so that an air fluid pressure is generated, and the front side of a magnetic head 10 is floated, and the rear side is brought into contact. Accordingly, in a part where the gap 15 is formed, the magnetic head 10 and the magnetic recording medium are brought into contact enough with each other and recording and reproduction can be executed stably, and a load to the medium can be made small, therefore, the durability of the medium can be improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a magnetic head that records and reproduces signals by contacting a magnetic recording medium, and particularly relates to a magnetic head that records and reproduces signals by contacting a magnetic recording medium. This article relates to an improved magnetic head.

(Prior Art) Conventionally, as a magnetic recording and reproducing device for recording and reproducing signals,
Various floppy disk devices are used. 7th
The figure shows a magnetic head used in a general floppy disk device. The magnetic head 70 is composed of two sliders 71 and 72, one of which is the slider 71.
A magnetic core 73 is formed in the magnetic core 73 . Further, the magnetic recording medium facing surface 74 of the magnetic head 70 has a planar shape. The magnetic gap 75 is located approximately at the center of the length of the flat portion of the magnetic core 73 in the direction in which the magnetic recording medium runs.

There are two types of floppy disk drives: single-sided and double-sided. The double-sided type is more advantageous in terms of storage capacity. A double-sided floppy disk device has a magnetic head 70 having the above structure.
As shown in FIG. 8, a magnetic recording medium 80 is sandwiched between the front and back surfaces, and signals are recorded and reproduced in this state. The upper and lower magnetic fields of the RAD slider face each other,
The magnetic cores 73 are positioned so as not to face each other in order to prevent magnetic interference between the upper and lower magnetic heads 70.

Also, the flat parts of the upper and lower magnetic heads 70 are connected to the magnetic recording medium 8.
9, both or either of the magnetic heads 70 are supported as shown in FIG. That is, the magnetic head 70 is attached to a gimbal spring 91, and the gimbal spring 91 is fixed to a carriage 92. The carriage 92 is provided with a pivot 93, which acts on the center of the length of the flat surface of the magnetic head in the direction in which the magnetic recording medium travels, and applies a pressing force to the magnetic head 70 via the gimbal spring 92. It is something to give.

By supporting the magnetic head 70 in this manner, the magnetic head 70 has a degree of freedom of rotation around the point of action of the pivot 93, and the uneven contact caused by mounting errors is prevented, and the flat surface of the magnetic head 70 is easily mounted. magnetic recording medium 80
I try to bring it into contact with.

The magnetic head and magnetic head support structure of a typical double-sided floppy disk drive have been briefly explained above.
In conventional double-sided floppy disk drives, in order to bring the magnetic gap into contact with the magnetic recording medium, the entire surface of the magnetic head facing the magnetic recording medium is brought into contact with the magnetic recording medium.

By the way, the points that must be taken into consideration when designing the magnetic head shape and magnetic head support structure are as follows: 1. Allow for errors in manufacturing and installation, and determine how large a margin the magnetic gap and magnetic recording medium can be brought into contact. Can you do it.

■ How can we reduce the load on magnetic recording media?

There are two points.

As mentioned above, in the case of a conventional double-sided floppy disk drive, in order to satisfy the first point, the surface of the magnetic head facing the magnetic recording medium is made flat, the magnetic head is gimbally supported, and the entire flat surface of the magnetic head is The idea is to bring the magnetic gap into contact with the magnetic recording medium by bringing the magnetic gap into contact with the magnetic recording medium. Further, in order to provide a larger margin, a method is adopted in which the pressing force of the magnetic head is increased or the area of the flat surface of the magnetic head is decreased, that is, the contact surface pressure of the entire surface of the flat surface of the magnetic head is increased. However, increasing the contact pressure on the entire flat surface of the magnetic head goes against the second consideration, which is to reduce the load on the magnetic recording medium. In other words, increasing the contact pressure on the entire flat surface of the magnetic head causes deterioration in the durability of the magnetic recording medium.

On the other hand, with the recent development of information processing technology, demands for higher capacity and reliability of magnetic recording and reproducing devices are increasing. In floppy disk drives, perpendicular magnetic recording media such as Go-Cr and B are used as media capable of high recording density.
Media such as a-Fe are being actively developed. Under these circumstances, in order to make full use of these media, establishing a technology to reduce the load on the magnetic recording medium and to obtain stable contact between the magnetic gap and the magnetic recording medium has become a major research topic.

(Problems to be Solved by the Invention) Conventionally, in order to easily bring the magnetic gap into contact with the magnetic recording medium, it is necessary to increase the contact pressure on the entire surface of the magnetic head facing the magnetic recording medium. However, there is a contradictory problem in that increasing the contact pressure deteriorates the durability of the magnetic recording medium.

The present invention has been made in consideration of the above circumstances, and an object of the present invention is to easily bring a magnetic gap and a magnetic recording medium into contact with each other while the load on the magnetic recording medium is sufficiently small. An object of the present invention is to provide a magnetic head that can contribute to improving the durability of a medium and improving the reliability of a magnetic recording/reproducing device.

[Structure of the Invention] (Means for Solving the Problems) The gist of the present invention is to bring only the vicinity of the magnetic gap into stable contact with the magnetic recording medium, thereby generating signals while minimizing the load on the magnetic recording medium. The objective is to record and play back information.

That is, the present invention has a flat portion facing the magnetic recording medium,
In a magnetic head that records and reproduces signals by bringing a magnetic gap formed in the flat part into contact with the medium, the magnetic gap is arranged on the rear end side of the flat part from the center of the length of the magnetic recording medium in the running direction, Further, a taper or a step is provided on the rear end side of the flat portion in the direction in which the magnetic recording medium runs.

(Function) In the conventional magnetic head and magnetic head support structure, in order to make the contact surface pressure between the magnetic gap part and the magnetic recording medium Pa, the entire surface of the magnetic head part is set to P as shown in FIG. 4(a).
The contact surface pressure will be a. Therefore, magnetic head 1
The plane area of 0 is S, the magnetic head 10 and the magnetic recording medium 3
0, the magnetic recording medium 30 receives a frictional force of Ft=Pa −8·μ from the magnetic head 10. This is the same even when there is a change in contact pressure as shown in FIG. 4(b).

In contrast, in the present invention, for example, by providing a taper so that air fluid is generated from the magnetic recording medium inflow end side of the magnetic head, the front end of the magnetic head 10 automatically flies when the magnetic recording medium runs, and the rear end It is possible to create a state in which only the vicinity of the magnetic gap located on the side is in partial contact with the magnetic recording medium 30. FIG. 5 shows the state of contact between the magnetic head 10 and the magnetic recording medium 30 at this time.

Here, the boundary between the floating part and the contacting part of the magnetic head 10 is taken as the center position of the magnetic head flat part in the magnetic recording medium traveling direction, the magnetic gap is taken as the rearmost end of the magnetic head flat part, and the magnetic gap The contact pressure at the part is P
Let it be a. Assuming the above three points, magnetic recording medium 3
0 will only receive friction from the magnetic head 10 of at most F2=(1/4)Pro・S・μ. Note that the magnetic recording medium 30 also receives frictional force from air fluid, but this value is different from the magnetic head 1.
0 and the magnetic recording medium 30, so it can be ignored. In other words, the more the boundary between the floating part of the magnetic head and the contact part is at the rear end of the magnetic head, the smaller the frictional force can be. Therefore, according to the present invention, the load on the magnetic recording medium can be sufficiently reduced, and the magnetic gap and the magnetic recording medium can easily come into contact.

Incidentally, a magnetic head has a R/W gap and an erase gap as magnetic gaps, and an excitation coil is wound around a magnetic material forming each gap. That is, as shown in FIG. 6, excitation coils 18 and 19 are wound around the magnetic core 13, respectively.
3 is sandwiched between holders 61 and 62.

Here, in order to place the magnetic gap at the rear end of the flat part of the magnetic head, either the diameter of the winding hole L af on the front end side and the diameter Lmf of the winding part magnetic body are increased, or the diameter of the winding hole on the rear end side L ab,
It is necessary to reduce the diameter LIb of the magnetic material in the winding portion. In the former case, the magnetic gap will be relatively located at the rear end of the flat part, but since the area of the flat magnetic head part will be large, the above-mentioned magnetic gap will be located at the rear end of the flat part of the magnetic head. The effect cannot be expected. Furthermore, in the latter case, if the diameter of the winding hole becomes small, it becomes difficult to wind the excitation coil. Furthermore, if the diameter of the magnetic material in the winding portion is made small, there are problems such as the magnetic material being easily damaged, and it is difficult to position the magnetic gap sufficiently at the rear end of the flat surface of the magnetic head.

Therefore, in the present invention, the above problem is solved by providing a taper or a step on the rear end side of the magnetic recording medium traveling direction from the flat part of the magnetic head. That is, in the configuration shown in FIG. 6, if a taper or step is provided on the rear end side in the magnetic recording medium running direction from the flat part of the magnetic head, the area of the flat part of the magnetic head becomes smaller, and the magnetic gap becomes smaller than the flat part of the magnetic head. It will be located on the rear end side. In this case, the winding hole diameter L ab on the rear end side, the winding part magnetic body diameter 1-mb
There is no need to reduce the size of the excitation coil, and it is possible to wind the excitation coil in the same state as before. Therefore, it is possible to set the position of the magnetic gap sufficiently at the rear end of the flat surface of the magnetic head without reducing the diameter of the winding hole or the diameter of the winding portion magnetic material on the rear end side of the magnetic head.

(Example) Hereinafter, details of the present invention will be explained with reference to illustrated embodiments.

FIG. 1 is a schematic configuration diagram showing the configuration of a magnetic head section according to an embodiment of the present invention. The magnetic head 10 is composed of two sliders 11 and 12, one of which has a magnetic core 13 formed therein. A surface 14 of the magnetic head 10 that comes into contact with the magnetic recording medium is machined to be flat, and an edge 16 on the side surface of the magnetic recording medium inflow end of the magnetic head 10 is chamfered so as to generate air fluid pressure.

Furthermore, a tapered portion is formed on the rear end side 17 of the magnetic head flat portion 14 in the magnetic recording medium running direction so as to be lower in height along the magnetic recording medium running direction.

Further, the magnetic gap 15 is formed not at the center of the flat portion 14 but at the rear end side in the running direction of the magnetic recording medium. That is, the length of the magnetic head flat part 14 is calculated from the front end of the magnetic head flat part 14 to the magnetic gap. When closed, the magnetic gap 15 is located at Lo/L=0.9. Note that there are two magnetic gaps 15, the front one being the R/W gap and the rear one being the erase gap. Further, reference numerals 18 and 19 in the figure indicate excitation coils wound around the magnetic core 13.

Note that the magnetic head 10 may be manufactured in the following manner, for example. First, as shown in FIG. 6, the magnetic core 13 and the holders 61, 63 are bonded together, and then this surface is polished to a flat surface in order to eliminate the level difference on the surface facing the magnetic recording medium caused by the bonding.

Next, the rear end side of the flat part 15 is tapered or stepped to position the magnetic gap 15 near the rear end of the flat magnetic head part 14 . after that,
By winding the excitation coils 18 and 19 around the magnetic core 13, the magnetic head 10 is completed. Also,
Instead of the above process, the magnetic core 13 and the holder 61°6, which have a taper or step on the rear end side of the magnetic gap 15, are used.
2, the magnetic core 13 and the holder 61, 62 are bonded together, the magnetic head flat portion 14 is formed, and the excitation coil 18 is bonded.
．． 19 windings may be performed.

The magnetic heads 10 described above are arranged facing each other with the magnetic recording medium in between, as shown in FIG. The magnetic recording medium is supported so as to have a degree of rotational freedom around the running direction. That is, the magnetic head 10 is supported at the center of the gimbal spring 21, and the gimbal spring 21 has its peripheral portion fixed to the carriage 22. Pivot 23 is fixed to carriage 22 = 13
- The tip of this pivot 23 is connected to the gimbal spring 2.
It is in contact with 1. Here, the point at which the robot 23 contacts the gimbal spring 21 is the center of the gimbal spring 21 in the radial direction of the magnetic recording medium, but it is on the rear end side of the center (for example, Lp / L = 0) in the traveling direction of the magnetic recording medium. .4
) is off. This is to more effectively float the front side of the magnetic head 10 and bring the rear side into contact.

With such a configuration, the contact state between the magnetic head and the magnetic recording medium is as shown in FIG. 5, and the magnetic head 1
The contact area with the magnetic recording medium 30 of 0 is small. In this case, since the magnetic head 10 and the magnetic recording medium 30 are in sufficient contact in the portion where the magnetic gap 15 is formed, recording and reproduction of signals can be performed stably. Therefore, the load on the magnetic recording medium 30 can be reduced, and the durability of the magnetic recording medium 3o can be improved. Furthermore, since the contact pressure between the magnetic head 10 and the magnetic recording medium 30 can be made sufficiently large at the magnetic gap position, it is possible to stably record and reproduce signals, thereby increasing the reliability of the magnetic recording and reproducing device. You can make improvements.

Furthermore, since the tapered portion 17 is provided on the rear end side of the magnetic recording medium traveling direction than the magnetic head flat portion 14, there is no need to reduce the diameter of the winding hole or the diameter of the winding portion magnetic material on the rear end side. This allows the magnetic gap 15 to be placed closer to the rear end.

Furthermore, since the load on the magnetic recording medium 30 is reduced, there are also advantages such as the power consumption of the motor for running the magnetic recording medium 30 can be reduced.

The inventors also conducted experiments using the example head and the conventional head, focusing on the output during signal recording and reproduction and the frictional force between the magnetic head and the magnetic recording medium, using the load as a parameter. The experimental results are shown in FIG.

Here, the O mark is the maximum output ratio in the example, the Δ mark is the friction coefficient in the example, the * mark is the maximum output ratio in the conventional example, and the mu mark is the friction coefficient in the conventional example. Further, the maximum output ratio is the ratio of the output value under each load to the output value when the magnetic gap and the magnetic recording medium are in ideal contact.

The maximum output increases as the load increases in both the embodiment and the conventional example, and becomes constant at 1.0 from a certain load onwards. In other words, the magnetic gap and the magnetic recording medium were in ideal contact under this load or more.

In the case of the conventional example, the friction coefficient does not depend on the load and is approximately constant at 0.2. On the other hand, in the example, 0 in the low load region
．． 05 or less, and as the load increases, the coefficient of friction approaches 0.2 in the case of the conventional example. The most noteworthy thing here is that in the example, as can be seen from the load 207 f, the friction coefficient is extremely low, 0.03, which is about 1/7 of the conventional example, and the maximum output ratio is 1. .0, which means that ideal contact between the magnetic gap and the magnetic recording medium was achieved.

Note that the present invention is not limited to the embodiments described above, and can be implemented with various modifications without departing from the gist thereof. For example, the magnetic gap position may be located closer to the rear end than the center of the length of the flat portion of the magnetic head in the running direction of the magnetic recording medium, and can be changed as appropriate depending on specifications. Similarly, the point of action of the pivot is not limited to Lp/L=0.4, but may preferably be on the rear end side of the center of the length of the flat portion of the magnetic head in the running direction of the magnetic recording medium. . In addition, instead of shifting the pivot position toward the rear end, the width of the flat part of the magnetic head is made smaller on the outflow side of the magnetic recording medium than on the inflow side, thereby creating a floating effect on the front side of the magnetic head. It is also possible. Further, instead of supporting one of the magnetic heads with the support mechanism as shown in FIG. 2, it is also possible to apply the present invention to one in which both magnetic heads are supported by the support mechanism.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to stably perform recording and reproduction on a magnetic recording medium while keeping the frictional force between the magnetic head and the magnetic recording medium sufficiently small. Therefore, it is possible to contribute to improving the durability of the magnetic recording medium and also to improving the reliability of the magnetic recording/reproducing device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a schematic configuration of a magnetic magnetic head according to an embodiment of the present invention, FIG. 2 is a diagram showing a schematic configuration of a support mechanism for the magnetic head, and FIG. A characteristic diagram showing the relationship between the maximum output ratio and the friction coefficient with respect to the load, which is used to explain the effects of the above embodiment, and FIGS. 4 to 6 are schematic diagrams for explaining the present invention in detail, and FIG. 9 to 9 are diagrams for explaining the conventional problems. 10...Magnetic head, 11.12...Slider, 1
3... Magnetic core, 14... Plane part, 15... Magnetic gap, 16... Corner part, 17... Taper part,
18.19... Excitation coil, 21... Cymbal spring, 22... Carriage, 23... Pivot, 30...
...Magnetic recording medium.

Claims (3)

[Claims] (1) In a magnetic head that has a flat part facing a magnetic recording medium and records and reproduces signals by bringing a magnetic gap formed in the flat part into contact with the medium, the magnetic head has a flat part facing the magnetic recording medium. What is claimed is: 1. A magnetic head, characterized in that a taper or a step is provided on the rear end side of the length center in the medium running direction, and on the rear end side of the magnetic recording medium running direction from the flat portion. (2) The magnetic recording medium is a double-sided recording/reproducing type flexible magnetic recording medium, and signals are recorded/reproduced by sandwiching the flexible magnetic recording medium from both sides. A magnetic head according to scope 1. (3) The front side of the flat portion in the running direction of the magnetic recording medium is
The magnetic head according to claim 1, characterized in that the magnetic head is chamfered.