JPH056567Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a magnetic head installed in a magnetic disk drive device, and particularly to a so-called double-sided magnetic disk drive that performs recording and reproduction on both sides of a magnetic disk. This relates to the magnetic head mounted on the device.

[Summary of the idea]

The present invention provides a magnetic head that combines a recording/reproducing head portion having a recording/reproducing gap and around which a recording/reproducing coil is wound, and an erasing head portion having an erasing gap and around which an erasing coil is wound. ,
By interposing a metal shield member between the sliding surface of the magnetic recording medium and each of the coils, magnetic coupling between the magnetic heads installed opposite each other in a double-sided magnetic disk drive device is achieved. The aim is to improve the magnetic characteristics, including reducing the output level of the magnetic head, by eliminating the crosstalk caused by the magnetic head.

[Conventional technology]

For example, magnetic disks such as floppy disks are relatively easy to handle and can record large amounts of signals, so they are increasingly used as external storage devices for various computers, word processors, and the like.

There are two types of floppy disks: single-sided disks that can record information signals on only one side of the disk, and double-sided disks that can record information signals on both sides of the disk.For example, recording and playback can be performed on double-sided disks. As shown in FIG. 4, the magnetic disk drive device includes a carriage portion 4 fixed to a guide bar or the like of the main body of the magnetic disk drive device (not shown).
1, and a movable arm part 42 which is rotatably fixed to the carriage part 41 in the direction of arrow X in FIG.
A device is known in which recording and reproduction are performed on both sides of a floppy disk 45 using magnetic heads 43 and 44 provided on each side.

The magnetic heads 43 and 44 built into such a magnetic disk drive device are designed to protect the magnetic core 51 around which the coil 49 is wound and the magnetic core 51, as well as to ensure contact of the sliding surface with the magnetic recording medium. It consists of a slider 50 provided at.

Incidentally, as the magnetic heads 43 and 44, a type in which the core 51 has a long leg and a coil 49 is installed outside the slider 50 is conventionally known. Since the length of the magnetic path to the surface becomes long and the electromagnetic conversion characteristics deteriorate, a magnetic head has been proposed in which the magnetic path is shortened and the coil is placed inside the slider. When such a magnetic head is attached to a magnetic disk drive device, as shown in FIG. 5, the coil does not protrude into the carriage portion 41 and movable arm portion 42 of the magnetic disk drive device, making it possible to downsize the device. The electromagnetic conversion efficiency is also good.

[Problem that the invention attempts to solve]

However, when the magnetic head in which the coil 49 is installed in the slider 50 as described above is attached to a double-sided magnetic disk drive device, the magnetic heads installed above and below so as to face each other with the floppy disk 45 in between are installed. The coils 49 of the heads 43 and 44 are very close to each other, and the coil 49 is attached to the slider 5.
Crosstalk occurs due to magnetic coupling, which would not be a problem with the magnetic heads 43 and 44 that protruded outside the head.

That is, by passing a write current through one of the magnetic heads 43, magnetic flux is generated in the coil within that magnetic head 43. Most of the generated magnetic flux flows through the head core and performs writing, but some of the magnetic flux leaks outside the core and reaches the coil of the other magnetic head 44. Then, a back electromotive force is generated in the coil, and a current flows to the head core, resulting in a write current, which causes writing to be performed on the opposite side to the side on which writing is being performed. As a result, various problems occur after writing, such as a decrease in the output level on the side opposite to the side on which writing was performed, a deterioration in the S/N ratio, and an increase in reading errors due to waveform distortion.

Therefore, the present invention was proposed to solve the above-mentioned problems, and is based on magnetic coupling between the magnetic heads of double-sided magnetic disk drive devices that face each other with a floppy disk in between. The purpose of this invention is to provide a high-performance magnetic head by eliminating the crosstalk caused by the magnetic head and improving various magnetic characteristics including the output level of the magnetic head.

[Means for solving problems]

In order to achieve the above object, the present invention provides a recording/reproducing head portion having a recording/reproducing gap and having a recording/reproducing coil wound thereon, and an erasing head portion having an erasing gap and having an erasing coil wound thereon. In a magnetic head in which a magnetic head element is sandwiched between sliders on a sliding surface with a magnetic recording medium, a shield member is inserted into the recording/reproducing head section and the erasing head section on the back side of the slider. The recording/reproducing coil and the erasing coil are fitted into the recording/reproducing head section and the erasing head section via the shield member.

[Effect]

In this way, the magnetic head of the present invention has a shielding member made of metal interposed between the sliding surface of the magnetic recording medium and each coil. A part of the leakage magnetic flux of the magnetic flux generated by the magnetic head is absorbed or repelled by the shield member, and can be prevented from leaking to the outside of the magnetic head. In other words, the magnetic coupling that occurs when the vertically opposing magnetic heads of a double-sided magnetic disk drive device are close to each other across the floppy disk is prevented, and crosstalk is eliminated, so the output level of the magnetic head and other Each magnetic property can be improved.

〔Example〕

An embodiment of a magnetic head to which the present invention is applied will be described below with reference to the drawings.

This embodiment is applied to a magnetic head mounted on a so-called double-sided magnetic disk drive device that performs recording and reproduction on both sides of a floppy disk.

As shown in FIGS. 1 and 2, the magnetic head of this embodiment has recording/reproducing core sections 1 on both sides of a center core section 3 which is magnetically separated via a non-magnetic material 3a.
and the erasing core part 2 on the front gap side, respectively, and the recording/reproducing gap _G1 and the erasing gap.
It consists of a front core 4 forming a _G2 and a back core 7 having a substantially E-shape, and is configured to form a closed magnetic path independently for each head section.

The erasing gap _G2 is configured to erase both ends of the recording track recorded in the recording/reproducing gap _G1 , and a so-called guard band is formed between each recording track recorded on the floppy disk. This makes it possible to obtain good recording and reproducing characteristics even if there is a slight off-track condition.

On the other hand, the back core 7 has approximately U-shaped core members 7a and 7b joined on the side surface via a non-magnetic material 7c, corresponding to the core shapes of the recording/reproducing head section and the erasing head section of the front core 4. The shape is approximately E-shaped. back core 7
By forming the front core 4 into a substantially E-shape, a bonding area between the cores can be secured without increasing the length of the front core 4 in the depth direction, and electromagnetic conversion characteristics can be improved. It also has many advantages in terms of component costs.

In addition, the recording/reproducing core section 1 and the erasing core section 2
A recording/reproducing coil 12 and an erasing coil 13 are wound around the legs 1a and 2a, respectively. The front core 4 and the back core 7 are overlapped in a so-called stacked state in the through hole 5a of the bobbin 5 of each of the coils 12 and 13, and are mechanically pressed by a pressing spring 8 to achieve magnetic coupling. It is being

Furthermore, in order to protect the front core 4 and ensure contact with the magnetic recording medium,
A pair of sliders 10 and 11 are arranged on both sides of the front core 4. A shield member 9 is interposed in the gap between the sliding surface of the magnetic recording medium of the slider 10, 11 and each of the coils 12, 13 to prevent magnetic coupling between the opposing magnetic heads with the floppy disk interposed therebetween.

As the shield member 9, for example, a non-magnetic metal material such as stainless steel, phosphor bronze, beryllium copper, aluminum, or nickel silver, or a soft magnetic metal material such as permalloy or sendust is used. When the above non-magnetic metal material is used, the magnetic flux is repelled by the shield member 9, and when a soft magnetic metal material is used, the magnetic flux is repelled by the shield member 9.
The magnetic flux is absorbed by the shield member 9 to prevent leakage of the magnetic flux.

Further, the shield member 9 has a size approximately equal to the inner side of the sliders 10 and 11 that sandwich the front core 4, and has a central portion so that it can be inserted into the front core 4 that is sandwiched between the sliders 10 and 11. It is composed of a thin plate with a long insertion groove 14 cut out in the vicinity.

The above-mentioned shield member 9 may be manufactured by a method such as press-cutting with a mold or forming an insertion groove 14 by etching. This increases the effect of preventing crosstalk due to coupling. However, if the thickness is too large, it becomes necessary to change the structure of the magnetic head and the shape of the members, which is not preferable. Therefore, the necessary and sufficient thickness is such that it fits in the gap between the sliding surface of the magnetic recording medium of the slider 10, 11 and each coil 12, 13 (in this embodiment, it is approximately 0.05 mm). If it is, there will be no practical problem and the full effect can be obtained.

The shield member 9 as described above exhibits its effect when inserted into the magnetic core consisting of the front core 4 and the back core 7 that constitute a magnetic path.
As shown in the figure, it is preferable that the shield member 9 be inserted in the middle of the magnetic path so as to be orthogonal to the magnetic path.

To assemble the magnetic head section, first insert the shield member 9 from the upper part of the front core 4 held between the sliders 10 and 11, and then insert the recording/reproducing coil 12 and the erasing coil 13 wound with coils. They are inserted into the reproducing core section 1 and the erasing core section 2, respectively. Next, add back core 7 to each coil 1
The rear presser spring 8 inserted into the bobbin 5 of 2 and 13
Just insert it from the top and fix it.

As described above, when inserting the shield member 9, no special operation is required, the operation is extremely easy, and the assembly process can be fully automated.

In the magnetic head of this embodiment, the shield member 9 prevents the magnetic flux generated in the coils 12 and 13 from leaking to the side facing the magnetic recording medium. Therefore, even if it is installed in a double-sided magnetic disk drive device as shown in FIG. 5, no magnetic coupling will occur between the opposing magnetic heads.

Although one embodiment of the present invention has been described above, the present invention is not limited to this. For example, a magnetic material may be applied to the surface of the bobbin 5 by coating, vapor deposition, plating, etc. It is also possible to integrally mold the shield member 9 with the shield member 9 to prevent leakage of magnetic flux. Further, a magnetic material may be applied to a part or all of the inner surfaces of the sliders 10 and 11 by coating, vapor deposition, plating, or the like to prevent leakage of magnetic flux. Further, the magnetic head to which the present invention is applied can be of various types, such as a pre-erase type, a straddle type, and a laminate type.

[Effect of idea]

As is clear from the above explanation, the magnetic head of the present invention has a shield member made of metal interposed between the sliding surface of the magnetic recording medium and each coil, so that it can be used in a double-sided magnetic disk drive. It is possible to prevent magnetic coupling that occurs between opposing magnetic heads, thereby eliminating crosstalk, improving the magnetic characteristics such as the output level of the magnetic head, and making it possible to create a high-performance magnetic head. .

In addition, the shield member is easily manufactured without the need for special processing, and the shield member can be loaded into the magnetic head without changing the structure of the magnetic head or the shape of the member, so it can be easily assembled in an automatic assembly process. It is also possible to respond.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a magnetic head showing an embodiment of the present invention, FIG. 2 is a cross-sectional view of essential parts of a magnetic head showing an embodiment of the present invention, and FIG. FIG. 3 is a perspective view showing the positional relationship between the shield member and the magnetic core inserted into the applied magnetic head. 4 and 5 are schematic side views of a double-sided magnetic disk drive device, respectively. DESCRIPTION OF SYMBOLS 1... Recording/reproducing head (core) part, 2... Erasing head (core) part, 9... Shield member, 12...
...recording/reproducing coil, 13...erasing coil, G ₁ ...
...Record/playback gap, G ₂ ...Erase gap.

Claims (1)

[Scope of Claim for Utility Model Registration] A recording/reproducing head portion having a recording/reproducing gap and having a recording/reproducing coil wound thereon, and an erasing head portion having an erasing gap and having an erasing coil wound therein are combined. In a magnetic head in which a magnetic head element consisting of a magnetic head element is held between a slider on a sliding surface with a magnetic recording medium, a shield member is disposed on the back side of the slider so as to be inserted through the recording/reproducing head section and the erasing head section, A magnetic head characterized in that a recording/reproducing coil and an erasing coil are fitted into a recording/reproducing head section and an erasing head section via the shield member.