JPH10340437A - Magnetic head and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To reduce the size while maintaining the head characteristics and mechanical strength. A disk sliding surface (4) in contact with a main surface of a magnetic disk (D) has at least an area (2) where a magnetic gap (21) is formed.
5 is formed as a convex curved surface. The core member 10 includes a magnetic disk D in a region 25 where the magnetic gap 21 is formed.
A projection 27 having a width substantially the same as that of the recording track is projected, and a nonmagnetic material 29 is filled in a recess 28 formed by the projection 27. The surface of the projection 27 and the surface of the non-magnetic material 29 constitute the disk sliding surface 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information signal such as a data signal, an audio signal, and an image signal or a control signal (hereinafter, referred to as a "magnetic disk") for a flexible magnetic disk such as a floppy disk. More specifically, the present invention relates to a magnetic head for recording and / or reproducing (hereinafter, simply referred to as recording / reproducing) and a method for manufacturing the same, and more particularly, to a high-density recording magnetic disk on which information signals and the like are recorded at a high density. And a method for manufacturing the same.

[0002]

2. Description of the Related Art A floppy disk drive generally drives a magnetic disk to rotate at a relatively low speed, and records and reproduces information signals and the like in a state where the disk sliding surface of a magnetic head is in contact with the main surface. It has a basic configuration and is characterized by low cost and high reliability.
A standard floppy disk drive using a 3.5-inch magnetic disk, which has a very high penetration rate, is one of the magnetic disk drives.
The storage capacity of information signals per sheet is 1.44 Mbytes,
The linear recording density (kBPI) is 17.4, and the track density (k
TPI) is 135, and the transfer rate of information signals and the like is 2
The basic specifications are requirements such as 50 Kb / s (or 500 Kb / s) and a drive speed of the magnetic disk of 300 rpm. This standard floppy disk drive is generally provided with a magnetic head composed of a ferrite head.

[0003] By the way, in personal computers and the like, the number of applications and applications have been remarkably expanded on the background of cost reduction and simplification of operability or maintenance and enhancement of a network. Under such circumstances, personal computers, etc. handle a wide range of information signals, such as information signals handled mainly from conventional document data signals, and multi-data such as image information signals and graphics data signals as in large computers. Etc. are to be handled. In order to cope with such a situation, a personal computer is provided with a disk exchange type external storage device as a standard equipment, and the use of a floppy disk device is being studied.

The standard type floppy disk drive is not suitable for handling large-capacity information signals for handling multimedia data due to the above-mentioned specifications such as storage capacity and driving speed. When applied as a replaceable external storage device, there is a problem that the storage capacity is insufficient. Therefore, in a floppy disk drive, there is a need to develop a large-capacity storage device that enables high-density recording of information signals and the like on a magnetic disk and rotates the magnetic disk at a high speed to improve a data transfer rate. Is underway. In addition,
In this specification, the specification for increasing the capacity is referred to as an upper specification, and the standard specification is referred to as a lower specification.

The floppy disk device has a storage capacity of 100 Mbytes for information signals and the like and a linear recording density (kBPI) of 43.
3. A higher specification floppy disk device is provided which uses a higher specification 3.5 inch magnetic disk having a track density (kTPI) of 2118 and rotates the higher specification magnetic disk at a high speed of 1200 to 3600 rpm. ing. The upper specification floppy disk device is generally provided with a metal-in-gap head as a magnetic head device. The use of, for example, a thin-film magnetic head or an MR head as a magnetic head device in a higher-specification floppy disk device is also being studied.

[0006]

By the way, in the magnetic head, the impedance of the core member and the coil can be reduced by enlarging the cross-sectional area of the core member or increasing the winding diameter of the coil. By increasing the number of turns, the head output is improved and the head characteristics are improved. On the other hand, in the magnetic head, as a measure to increase the density of the above-mentioned floppy disk drive, this magnetic flux is efficiently applied to the magnetic disk having a narrow track pitch through a magnetic gap. The magnetic gap must be narrowed to make it smaller, in other words, its size must be reduced.

However, the magnetic head causes a problem that the head characteristics are degraded by reducing the size of the magnetic head in response to the increase in density. That is, when a magnetic head uses a miniaturized core member having a small cross-sectional area, the head impedance becomes large, and it becomes difficult to maintain a sufficient number of turns of the coil. The problem arises that the temperature decreases.
In addition, when the number of turns is ensured by using a small-diameter winding for a downsized core member, the impedance of the winding increases, and the head impedance as a whole decreases. The problem that it becomes large arises. Further, the magnetic head has a problem that the mechanical strength is reduced by using the downsized core member, and the life of the head is shortened.

In the magnetic head, as the track pitch of the magnetic disk becomes narrower, the magnetic effect between the recording tracks, that is, the cross talk phenomenon increases. Therefore, the magnetic head has a recording / reproducing characteristic of an information signal or the like, that is, a track miss registration (T
(MR) is deteriorated. Further, when the magnetic disk is rotated at a high speed, the magnetic head causes a flying phenomenon due to an air flow generated between the disk sliding surface and the main surface of the magnetic disk. The magnetic disk has a problem in that the recording / reproducing characteristics of information signals and the like are deteriorated.

SUMMARY OF THE INVENTION Therefore, the present invention has been proposed to provide a magnetic head and a method of manufacturing the same, in which the head characteristics are improved by achieving substantial miniaturization while maintaining mechanical strength. It is.

[0010]

According to the present invention, there is provided a magnetic head according to the present invention, wherein a disk sliding surface held in a pseudo contact state with a main surface of a magnetic disk includes at least a magnetic gap forming region. The portion is formed as a convex curved surface, and the disk sliding surface of the core member is constituted by the upper end surface of the convex portion having substantially the same width as the recording track of the magnetic disk. And is filled with a non-magnetic material so as to constitute substantially the same surface as the above.

According to the magnetic head of the present invention configured as described above, the range of action of the magnetic field from the core member on the magnetic disk is narrowed down to the range of the recording track, thereby achieving a magnetic miniaturization. The magnetic efficiency with respect to the magnetic disk is improved, and the rise in head impedance is suppressed. Further, the magnetic head aims to improve the recording / reproducing characteristics of information signals and the like by reducing crosstalk even on a magnetic disk on which high-density recording has been achieved by narrowing the track pitch. Further, the magnetic head can provide a high head output because the coil can be formed by winding the core member with a sufficient number of turns or using a winding having a large diameter.

In the method of manufacturing a magnetic head according to the present invention, which achieves the above-mentioned object, a magnetic gap forming region is formed on the upper end surface of the core member so as to have substantially the same width as the recording track. A step of shaving the remaining area as a concave part and a step of filling a non-magnetic material so as to form a substantially same surface as the upper end face of the magnetic gap forming area convex part in the cut part, Grinding the surface formed by the convex portion of the magnetic gap forming region and the non-magnetic material to make the disk sliding surface a convex curved surface.

According to the method of manufacturing a magnetic head according to the present invention, the magnetic head having a magnetically miniaturized magnetic head achieved by narrowing the range of action of the magnetic field from the core member on the magnetic disk to the range of the recording track is extremely simple. It is manufactured in. The magnetic disk has improved magnetic efficiency with respect to the magnetic disk, suppresses an increase in the head impedance, and reduces the crosstalk even with a magnetic disk that has achieved high-density recording by narrowing the track pitch. Performs high-precision recording and reproduction.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. A pair of magnetic heads 1 shown in the drawings as an embodiment of the present invention are opposed to each other across a main surface of a magnetic disk D supported and rotated by a disk support mechanism (not shown). It is provided in a so-called double-sided floppy disk drive which records and reproduces information signals and the like from the main surface. The magnetic head 1 has, for example, a disk diameter of 3.5.
The lower specification magnetic disk DL which is inch and is driven to rotate at 300 rpm, and the upper specification magnetic disk DU which records information signals and the like at a high density and is driven to rotate at a high speed of, for example, 1200 to 3600 rpm can be used interchangeably. This is a composite magnetic head mounted on a dual-purpose floppy disk drive.

The dual-purpose floppy disk drive performs a recording / reproducing operation of an information signal or the like while holding the composite magnetic head 1 in a state of being substantially in contact with both main surfaces of the magnetic disk D. The dual-purpose floppy disk drive has a composite magnetic head 1
When a lower specification magnetic disk DL is loaded, non-tracking servo is performed, and when a higher specification magnetic disk DU is loaded, tracking servo is performed to read / write information signals and the like from these magnetic disks D. I do.

The composite magnetic head 1 includes a lower specification magnetic head unit 2 for recording and reproducing information signals and the like from the lower specification magnetic disk DL and an upper specification magnetic head unit 3 for recording and reproducing information signals and the like from the higher specification disk DU. Are integrally provided. The composite magnetic head 1 is mounted on a head support mechanism (not shown) having a gimbal spring or the like, for example. The composite magnetic head 1 is held substantially in contact with the main surface of the magnetic disk D rotating and running from left to right as shown by an arrow A in FIG.

The disk sliding surface 4 of the composite magnetic head 1 is centered on a head center line HL through a groove 5 described later provided in parallel with the disk rotation direction A as shown in FIGS. And is divided into a first area 6 and a second area 7 in the width direction. In the composite magnetic head 1, the disk sliding surface 4 is formed as a composite convex curved surface having a different radius of curvature R, as will be described in detail later.

The composite magnetic head 1 has a lower specification magnetic head 2 and a higher specification magnetic head 3 disposed in a first area 6. The lower specification magnetic head unit 2 is configured as a tunnel erase type bulk type head similar to a magnetic head device mounted on a conventional lower specification floppy disk device. As will be described in detail later, the upper specification magnetic head unit 3 is constituted by a metal-in-gap head in which a magnetic metal film is formed on a groove wall of a gap groove by a sputtering method.

The composite magnetic head 1 has a first core member 8 formed by joining a pair of core halves constituting the lower specification magnetic head portion 2, and a second core formed by joining a pair of core halves. And a member 9. The composite magnetic head 1 has a third core member 10 formed by joining a pair of core halves 10a and 10b constituting a higher-specification magnetic head portion 3, which will be described in detail later.
And a pair of reinforcing members 12 (12a, 12b). The composite magnetic head 1 includes a spacer member 13 for magnetically separating the lower specification magnetic head unit 2 and the higher specification magnetic head unit 3, and a first slider member 14 forming one side surface of the lower specification magnetic head unit 2. And a second slider member 15 forming the second region 7.

The composite magnetic head 1 includes a read / write coil (not shown) combined with a first core member 8 constituting the lower specification magnetic head portion 2 and a lower end portion of a core half of the first core member 8. Are joined together to form a closed magnetic circuit, and an erase coil (not shown) combined with the second core member 9. The composite magnetic head 1 includes a pair of read / write coils 16 (1) combined with the core halves 10 a and 10 b of the third core member 10 that constitutes the upper specification magnetic head unit 3.
6a, 16b) and a back core member 17 that joins the lower ends of the core halves 10a, 10b to form a closed magnetic circuit.

The first core member 8 constituting the lower specification magnetic head portion 2 is formed of a ferrite block material as a thin rectangular block having a long side in the disk rotation direction A, and is formed through a gap groove. Disk rotation direction A
Is divided into a pair of front and rear core halves. The first core member 8 is formed by filling a gap glass with molten glass and joining the core halves to form a read / write gap 18 at this joint.

The second core member 9 is also made of a ferrite block material and has a rectangular block shape substantially the same as that of the first core member 8, and is formed in the disk rotation direction A via a gap groove. It is divided into a pair of front and rear core halves. An erase gap 19 is formed in the second core member 9 by filling the gap groove with molten glass and joining the core halves together.
Note that this erase gap 19 is
In order to make both sides of the recording track a silent region, a pair is formed apart from each other in the width direction of the second core member 9.

The first core member 8 configured as described above
The second core member 9 and the second core member 9 are joined in series to each other by a glass welding portion 20 in the disk rotation direction A. In the first core member 8, a read / write coil is attached to one core half, and a back core member is joined. The second core member 9 has an erase coil attached to one core half and a back core member joined thereto. The first core member 8 and the second core member 9 are thereby connected to the lower specification magnetic head 2.
Is configured.

In the lower specification magnetic head section 2, a read / write gap 18 formed in the first core member 8 reproduces information signals or the like recorded on a rotationally driven lower specification magnetic disk DL or lowers. Information signals and the like are recorded on the magnetic disk DL. The lower specification magnetic head 2 is shown in FIG.
The read / write gap 18 is formed slightly forward of the center O in the disk running direction A as shown in FIG. In the lower specification magnetic head section 2, a pair of erase gaps 19 formed in the second core member 9 constitute a non-recording section for information signals or the like on both sides of each recording track. The lower specification magnetic head unit 2 holds a guard band between recording tracks so that an information signal or the like is recorded at a fixed width on a recording track of the lower specification magnetic disk DL.

The lower specification magnetic head 2 described above
Is constituted by a tunnel erase type bulk type head, but by other appropriate magnetic heads such as a laminate type head or a straddle erase head used in a conventional floppy disk drive. Of course, it may be constituted.

The third core member 10 constituting the upper specification magnetic head 3 is made of a ferrite block material having a long side in the disk rotation direction A, and as shown in FIG. Are divided into a core half 10a and a core half 10b. The third core member 10 has a metal-in-gap 21 formed by forming a magnetic metal film 24 on the groove wall of the gap forming groove 22 and filling the molten glass 20 with the groove as described later.
As shown in FIGS. 1 and 2, the third core member 10 has a thickness and a height corresponding to the upper specification magnetic disk DU having a narrow track pitch. The first core member 8 and the second core member 9 are smaller than the thickness dimension and the height dimension.

Core Half 1 Constituting Third Core Member 10
As shown in FIG. 3 and FIG. 4, the gap forming grooves 22 (22a, 22b) forming the metal-in-gap 21 are formed on the inner surface of the core half 10a and the core half 10b. The read / write coil 16 is provided on each of the legs 23 (23a, 23b). The gap forming groove 22 defines the depth of the metal-in-gap 21, and the angle θ1 of the groove wall is 45 ° to 5 °.
It is set to 5 °.

The core halves 10a and 10b are abutted against each other in the disk rotation direction A in series with each other, and are filled with the molten glass 20. As shown in FIG. 3 and FIG. A third core member 10 is provided. The third core member 10 includes the core half 1
A metal-in-gap 21 is formed by forming a magnetic metal film 24 made of sendust or the like on the groove wall of the gap forming groove 22 of 0b by a sputtering method.

As shown in FIGS. 3 to 5, the third core member 10 has a gap constituting part 25 (25a, 25a, 25a) constituting the metal-in-gap 21 of the core halves 10a, 10b.
25b) is configured such that the cross-sectional area of the leg portion 22 is reduced. That is, the core halves 10a, 10a
b is an inclined surface 26 (26a, 2a) whose upper end is inclined so that the width in the disk rotation direction A gradually decreases from the leg portion 22 toward the disk sliding surface 4 side.
6b). The angle θ of the inclined surface 26
2 are each set to 15 ° to 60 °.

As described above, the core halves 10a and 10b
Is configured such that the groove wall of the gap forming groove 22 has an inclined angle θ1 with respect to the inclined wall. Therefore,
In the third core member 10, the width of the gap forming portion 25 constituting the disk sliding surface 4 on which the metal-in-gap 21 is formed is reduced by shaving both side portions in the disk rotation direction A. Then, the metal-in-gap 21 is narrowed down.

On the other hand, as shown in FIGS. 5 and 6, the third core member 10 has a recording track width TRW of the upper specification magnetic disk DU in a gap forming portion 25 on the upper end surface constituting the disk sliding surface 4. Convex portion 2 having a width dimension substantially equal to
Reference numeral 7 protrudes integrally over the entire area in the disk rotation direction A. The third core member 10 has a disk sliding surface formed in a wide track width similar to that of a conventional magnetic head in a manufacturing process described later in detail, and then has a track width formed by a convex portion 27 formed in a subsequent process. Is formed. Although the third core member 10 is formed using a ferrite block material as described later, it is difficult to form the side edges with high dimensional accuracy. Therefore, in order to maintain the accuracy of the width dimension, the convex portion 27 is formed to be located slightly inside from one side surface of the third core member 10 as shown in FIG.

The third core member 10 has the above-described protrusion 2
The non-magnetic material, for example, the molten glass 2
9 are filled. The molten glass 29 has the same surface as the upper end surface of the convex portion 27, thereby constituting the disk sliding surface 4 of the third core member 10 as a whole. Therefore, the third core member 10 is
The range of action of the magnetic field on the upper specification magnetic disk DU defined by the above is narrowed down to the range of the recording track.

As described above, the third core member 10 is configured such that the cross-sectional area of the gap constituting portion 25 is made smaller than that of the base end portion, and the action range of the magnetic field is narrowed to the range of the recording track. However, the overall size is substantially the same as the core member of the conventional magnetic head. Therefore, the third core member 10 is suppressed from having a high head impedance as a whole. Further, the third core member 10 has a read / write coil 16 having a sufficient number of turns or a large-diameter winding on its leg 23.
Can be provided, and the output of the head can be improved. Further, the third core member 10 suppresses crosstalk between recording tracks on the upper specification magnetic disk DU having a narrow track pitch.

The third core member 10 is a core half 1
When the half angle of the inclination angle θ1 provided to the groove walls of the gap configuration grooves 22 of 0a and 10b and the angle θ2 of the inclined surface 26 are substantially the same, the sectional area of the gap configuration portion 25 is Configured uniformly. By adopting such a configuration, the third core member 10 suppresses the occurrence of magnetic saturation in the gap-constituting portion 25 and improves the magnetic efficiency.

In the third core member 10, the gap forming grooves 22 of the core halves 10a, 10b having the inclined surfaces 26 are formed.
Reinforcing members 12 are bonded to each side surface of the upper surface with water glass or low melting point glass, thereby forming the upper specification magnetic head portion 3. The reinforcing member 12 is formed of a non-magnetic ceramic material having excellent wear resistance, sliding resistance, and mechanical properties such as calcium titanate. The reinforcing member 12 is connected to the third core member 10.
As shown in FIG. 3, butting protruding edges 30 (30a, 30b) each having a substantially triangular cross-section are integrally provided on the butting surface.

The angles of the slopes of these butted protruding edges 30 are substantially the same as the angle θ2 of the inclined surfaces 26 of the core halves 10a and 10b. The reinforcing member 12 is configured to convert the slopes of the butt projections 30 into the slopes 26 of the core halves 10a and 10b.
By joining them together, they are combined in a state orthogonal to the third core member 10. The upper surface of the reinforcing member 12 constitutes the disk sliding surface 4 together with the upper surface of the gap constituting portion 25 of the third core member 10.

Further, the reinforcing member 12 is formed by the third core member 1.
In the state where the lower specification magnetic head portion 2 is joined to the lower specification magnetic head portion 2, the upper specification magnetic head portion 3 has the same length as the lower specification magnetic head portion 2 in the disk rotation direction A as shown in FIG. . Therefore, the higher specification magnetic head unit 3 is configured such that the metal-in-gap 21 is formed in the disk rotation direction A by joining the third core member 10 and the reinforcing member 12.
Is formed substantially at the center. The upper specification magnetic head portion 3 joins the reinforcing member 12 to the third core member 10 in which both sides of the metal-in gap 21 are cut and the gap constituting portion 25 is reduced in size. Since the mechanical strength of the core member 10 is maintained, the life of the head does not decrease.

The upper specification magnetic head portion 3 is configured such that the third core member 10 is reduced in size with respect to the first core member 8 and the second core member 9 by the above-described configuration.
The magnetic influence on the lower specification magnetic head unit 2 is suppressed, and the crosstalk between the magnetic tracks of the higher specification magnetic disk DU is suppressed. In addition, the upper specification magnetic head 3
Since the gap component 25 is substantially reduced in size and a magnetic field is efficiently applied to the magnetic disk D via the metal-in gap 21, the magnetic efficiency is improved. The upper specification magnetic head unit 3 reproduces an information signal or the like recorded on the upper specification magnetic disk DU whose metal-in-gap 21 is rotationally driven, or records an information signal or the like on the upper specification magnetic disk DU. Since the magnetic efficiency of the metal-in-gap 21 is improved, the higher-order specification magnetic head unit 3 can accurately output information signals and the like even when a high-frequency recording wavelength is used to achieve higher-density recording. Recording and reproduction.

The spacer member 13 is made of a non-magnetic ceramic material having excellent wear resistance, sliding resistance and mechanical properties, such as calcium titanate, as shown in FIG. For the lower specification magnetic head 2
It is formed as a thin rectangular block having substantially the same length as. The spacer member 13 is interposed between the lower specification magnetic head portion 2 and the higher specification magnetic head portion 3 over the entire area in the disk rotation direction A and is joined by molten glass. The spacer member 13 magnetically separates the lower specification magnetic head 2 and the higher specification magnetic head 3 from each other.

The first slider member 14 is also made of a non-magnetic ceramic material, such as calcium titanate, which is excellent in abrasion resistance, sliding resistance and mechanical properties. As shown in FIG. Lower specification magnetic head 2 for direction A
It is formed as a rectangular block having substantially the same length as. As shown in FIGS. 1 and 2, the first slider member 14 is disposed on the side facing the joining surface of the spacer member 13 with respect to the lower specification magnetic head 2 in the disk rotation direction A.
Are joined by the molten glass over the entire area of. Therefore, the first slider member 14 mechanically protects the lower specification magnetic head portion 2 by forming one side surface portion parallel to the disk rotation direction A of the composite magnetic head 1.

The second slider member 15 is also made of a non-magnetic ceramic material such as calcium titanate which is excellent in abrasion resistance, sliding resistance and mechanical properties, as shown in FIGS. 1 and 2. The upper surface specification magnetic head portion 3 is joined to the side surface opposite to the joining surface of the spacer member 13 by molten glass over the entire area in the disk rotation direction A. In the second slider member 15, a groove 5 is formed on the main surface of the disk sliding surface 4 over the entire area in the disk rotation direction. As shown in FIG. 1, the groove 5 is recessed at a central region in the width direction of the composite magnetic head 1.

By the way, in the composite magnetic head 1,
From the above-described configuration, the center line CL of the third core member 10 configuring the upper specification magnetic head unit 3 is eccentrically positioned laterally with respect to the head center line HL. As shown in FIG. 5, the upper specification magnetic disk DU has its center line TRL of the recording track positioned on the center line CL side of the higher specification magnetic head unit 3 with respect to the head center line HL. Therefore, the composite magnetic head 1 is provided with a higher specification magnetic disk DU.
In contrast to this, the recording / reproducing of an information signal or the like is performed while maintaining the pseudo contact state on the recording track in a state where the upper specification magnetic head unit 3 is more stable.

The composite magnetic head 1 has the first core member 8 and the second core member 9, the third core member 10 and the reinforcing member 12, the spacer member 13, and the first slider member configured as described above. The second slider member 15 and the second slider member 15 are joined to each other in the thickness direction through a manufacturing process described later. As shown in FIG. 1, the composite magnetic head 1 has a disk sliding surface 4 having a generally rectangular surface having a groove 5 formed along the head center line HL and parallel to the disk rotation direction A. Is done. Disk sliding surface 4
Is composed of an inner peripheral curved surface region 31 having a radius R1 around the center O of the head, an outer convex curved surface region 32 and an outer peripheral region 33 having a radius R2. The disk sliding surface 4 is configured such that the inner peripheral convex curved surface region 31 is a convex curved surface with a radius of curvature R3, and the outer peripheral region 33 is a convex curved surface with a radius of curvature R4.

The composite magnetic head 1 has an inner peripheral curved surface area 3
1, a read / write gap 18 and an erase gap 19 of the lower specification magnetic head unit 2 and a metal-in gap 21 of the higher specification magnetic head unit 3 are located. The composite magnetic head 1 is formed into an inclined convex curved surface which is gradually and gradually inclined from the outer peripheral curved surface region 32 toward the outer peripheral edge by performing the blending process on the outer peripheral region 33. The composite magnetic head 1 has an arc-shaped chamfer 34 on the outer peripheral edge.

The composite magnetic head 1 has a disk rotation direction A
Has an external specification in which the length dimension L is 3.0 mm, the width dimension W is 2.8 mm, and the height dimension H is 2.7 mm. In the composite magnetic head 1, the radius R1 of the inner-circumferential curved surface area 31 is set to be equal to or smaller than 0. 1 so that the read / write gap 18 and the erase gap 19 correspond to the track pitch of the lower specification magnetic disk DL. It is set to 9 mm. In the composite magnetic head 1, the inner peripheral convex curved surface region 31 has a radius of curvature R3 of 1000 mm or more, specifically 9 mm.
000 mm.

The composite magnetic head 1 has an outer peripheral curved surface area 3
2 has a radius R2 of 1.25 mm and a curvature radius R4 of 50 mm or more and less than 1000 mm, specifically 1
It is configured as a convex curved surface of 00 mm. The composite magnetic head 1 is configured such that the outer peripheral region 33 has an inclination angle of 15 ° to 20 °. The composite magnetic head 1 includes:
The groove width of the groove 5 is set to 0.4 mm.

Since the composite magnetic head 1 has the disk sliding surface 4 formed as a composite convex surface as described above, even when the upper specification magnetic disk DU is driven to rotate at a high speed, the floating phenomenon from the main surface thereof occurs. Is suppressed.
The composite magnetic head 1 has a range of 0.4 mm before and after the center O of the head with respect to the disk rotation direction A and 0.45 mm left and right with respect to the width direction (0.8 mm × 0.9 in total).
mm) constitutes a pseudo contact region with an interval of 10 nm or less.

Therefore, in the composite magnetic head 1, the higher specification magnetic head unit 3 maintains a pseudo contact state with the higher specification magnetic disk DU, and performs recording and reproduction of information signals and the like with high accuracy. Further, the composite magnetic head 1 has an outer peripheral region 33.
The surface of the magnetic disk D is moved away from its main surface in accordance with the rotation of the magnetic disk D during recording and reproduction of information signals and the like by performing a blending process to form a gentle inclined surface and performing an arc-shaped chamfer 34. In this case, the magnetic disk D is not damaged. In the composite magnetic head 1, since the metal-in-gap 21 of the higher-specification magnetic head portion 3 is formed at the center in the longitudinal direction, tilt loss at the time of recording and reproducing information signals and the like is suppressed, High-precision recording / reproduction is performed.

The composite magnetic head 1 configured as described above
As shown in FIG. 7, is manufactured through a manufacturing process of the lower specification magnetic head unit 2, a manufacturing process of the upper specification magnetic head unit 3, a joining process of the constituent members, a cutting process, and the like. The manufacturing process of the lower specification magnetic head unit 2 includes a manufacturing process of the first core member 8 and a manufacturing process of the second core member 9, and the first core member 8 and the second The lower specification magnetic head portion 2 is manufactured through a process of integrally joining the second core member 9 with the second core member 9. First core member 8
Is a block forming step S-1 for forming a ferrite block material as a raw material into a predetermined block shape as a first step. The ferrite block material has a size that allows a large number of first core members 8 to be cut out.

In the ferrite block material, in the groove forming step S-2 of the second step, the read / write gap 18 is divided into a first core half and a second core half.
Are formed over the entire length of one main surface. In the ferrite block material, the glass fusion step S-3 of the third step is performed.
The first and second core halves are joined by molten glass to form a read / write gap 18.
Is configured.

Further, the ferrite block material is the fourth material.
In the side surface processing step S-4 of the above step, the outer dimensions are set in the disk rotation direction A and finished with a predetermined surface accuracy. The ferrite block material is cut into a predetermined shape, so that one side surface in the longitudinal direction constitutes a tip surface in the disk rotation direction A,
The other side surface in the longitudinal direction forms a joint surface with the second core member 9.

The second core member 9 is manufactured through substantially the same process as the manufacturing process of the first core member 8 described above, and is subjected to a block forming step S for forming a ferrite block material as a material into a predetermined block shape. -5 is defined as a first step. This ferrite block material has a size that allows a large number of second core members 9 to be cut out. In the ferrite block material, in the groove forming step S-6 of the second step, a gap forming groove for forming the erase gap 19 by being divided into a first core half and a second core half. And a track groove are formed over the entire length of the one main surface.

In the ferrite block material, the first core half and the second core half are joined by molten glass in the glass fusing step S-7 of the third step, so that an erase gap 19 is formed. Be composed. In addition, ferrite
The block material is formed in the fourth step of the side surface processing / groove forming step S-
At 8, the external dimensions are set to a predetermined value in the disk rotation direction A, and the surface is finished with a predetermined surface accuracy. In the ferrite block material, one side surface in the longitudinal direction forms a rear end surface in the disk rotation direction A, and the other side surface in the longitudinal direction forms a joint surface with the first core member 8.

The first core member 8 and the second core member 9 manufactured through the above-described steps have their end faces facing each other in the glass fusing step S-9, in other words, in the disk rotation direction. A is butt-connected in series and joined together by molten glass. The molten glass filled in this joint is, as described above, the first core member 4
And the second core member 6 are magnetically isolated. A concave portion forming step S-10 for forming a concave portion constituting an assembly space of the read / write coil and the erase coil 16 in the bottom surface of the manufactured bonded ferrite block body.
Then, a spacer joining step S-11 of joining the spacer member 13 to the side surface is performed. The bonded ferrite block body is cut into a predetermined size in the cutting step S-12 to form a core chip constituting the lower-specification magnetic head unit 2.

The first step in the manufacturing process of the upper specification magnetic head unit 2 is a block forming step S-13 for forming a ferrite block material into a predetermined block shape.
The ferrite block material 30 has such a size that a large number of third core members 10 can be cut out. In the groove forming step S-14 of the second step, the ferrite block material 30 is divided into a first core half 30a and a second core half 30b as shown in FIG. As a result, a gap forming groove 31 for forming the metal-in-gap 21 is formed over the entire length.

In the ferrite block material 30, in the magnetic metal film forming step S-15 of the third step, the gap which is the abutting part of the first core half 30a and the second core half 30b is formed. The magnetic metal film 24 is formed on the groove walls of the constituent grooves 31 by the sputtering method. The metal-in-gap 21 is formed in the ferrite block material 30 by filling the gap forming groove with molten glass in the fourth glass fusion step S-16. The molten glass filled in this joint constitutes the glass weld 20 of the metal-in-gap 21.

In the ferrite block material 30 having undergone the above steps, the outer peripheral side face is finished with a predetermined shape and surface accuracy in the fifth step on both side working steps S-17, and FIG. As shown in B), the inclined surfaces 32 are respectively formed on the upper end portions of the outer surfaces corresponding to the gap constituting portions 25 of the first core half portion 30a and the second core half portion 30b.
a, 32b are formed over the entire area in the length direction. In the both-side processing step S-17, a track groove corresponding to a recording track is formed on the upper end surface of the ferrite block material 30. This track groove is formed wider than the recording track pitch of the upper specification magnetic disk DU.

In the track width processing step S-18 of the sixth step, the ferrite block material 30 is subjected to precision grinding on the upper end surface of the ferrite block material 30.
As shown in FIG. 9, concave grooves 34 forming a large number of convex portions 33 having a width substantially equal to the recording track pitch of the upper specification magnetic disk DU are formed. Each of the protrusions 33 is provided in the magnetic gap component 2 of the upper specification magnetic disk unit 3 described above.
5 constitute the convex portion 27. In the ferrite block material 30, the glass filling step S-19 of the seventh step is performed.
, The molten glass 29 is filled in each of the cut grooves 34. The molten glass 29 is filled in each groove 34 so as to form substantially the same surface as the upper end surface of the projection 33.

In the reinforcing member joining step S-20 of the eighth step, the ferrite block material 30 is formed as shown in FIG.
As shown in (2), a reinforcing block member 35 constituting the reinforcing member 12 is covered and joined to the upper end portion where the convex portion 33 is formed. As shown in FIG.
On the bottom surface side, a fitting groove 35a having a groove wall having an inclination substantially equal to the inclined surface 32 formed on both side surfaces of the ferrite block material 30 is formed. Reinforcement block material 35
Is made of water glass or low melting glass
It is joined to the block material 30. The ferrite block material 30 is filled in the glass filling step S-19 as described above.
In the above, the molten glass 29 is filled in the concave groove 34, but a low-melting glass for joining the reinforcing block material 35 may be used as the molten glass 29 for filling the concave groove 34.

The ferrite block material 30 is shown in FIG.
(D) As shown in FIG.
5 has a substantially T-shape protruded integrally in a horizontal state. After the ferrite block material 30 is subjected to the ninth groove forming step S-21 of forming a concave portion forming the assembly space of the read / write coil 16 on the bottom surface portion,
Is cut into a predetermined shape in the cutting step S-22 in the step (b), whereby the upper specification magnetic head portion 3 is cut.
Is formed.

The core chip forming the lower specification magnetic head 2 and the core chip forming the higher specification magnetic head 3 manufactured through the above-described steps S-1 to S-22 are combined with a glass welding step S-23. In the spacer member 13
Opposite side surfaces are joined by a molten glass through the glass and integrated. The block body of the lower specification magnetic head 2 and the upper specification magnetic head 3 is subjected to a cutting step S-2.
In 4, the sheet is cut into a predetermined outer shape in the track width direction including the spacer member 13.

A slider joining step S-2 is applied to the block body of the lower specification magnetic head 2 and the upper specification magnetic head 3.
5, a first slider member 14 and a second slider member 15 are provided on both side surfaces thereof in the disk rotation direction A, respectively.
To form a magnetic head intermediate. The magnetic head intermediate is formed in a groove groove forming step S-26.
The disk sliding surface 4 of the second slider member 15
A groove 5 having a predetermined width is formed in parallel with the disk rotation direction A. Further, in the sliding surface processing step S-27, the magnetic head intermediate body is subjected to a process of setting the disk sliding surface 4 to have the above-described composite convex curved surface. The intermediate surface of the magnetic head forms the disk sliding surface 4 by grinding the surface of the reinforcing block material 35 and exposing the upper end surface of the convex portion 33 and the molten glass 29 in the sliding surface processing step S-27. The magnetic head intermediate body is further subjected to a blending step S-28 for chamfering the outer peripheral edge portion 33 and the like, thereby completing the composite magnetic head 1, in other words, the magnetic head chip.

The composite magnetic head 1 manufactured through the above steps is mounted on a dual-purpose floppy disk drive which is compatible with a lower specification magnetic disk DL and a higher specification magnetic disk DU in combination with a head support mechanism. You. The composite magnetic head 1 is configured such that the disk sliding surface 4 is formed as a composite convex curved surface even when the upper specification magnetic disk DU is loaded and rotated at a high speed of, for example, 3600 rpm. And the recording and reproduction of information signals and the like are performed with high accuracy while maintaining the pseudo contact state.

In the composite magnetic head 1, the magnetic efficiency is improved and the crosstalk is reduced by configuring the upper specification magnetic head section 3 as described above. In the composite magnetic head 1, the magnetic gap constituting portion 25 of the core member 10 of the upper specification magnetic head portion 3 is reduced in size. However, by combining the core member 10 with the reinforcing member 12, the occurrence of uneven wear is suppressed, and High mechanical strength is maintained. Therefore, the head life of the composite magnetic head 1 does not decrease. Further, in the composite magnetic head 1, the third core member 10 is large as a whole, and the number of turns of the coil constituting the read / write coil 16 is increased or the diameter of the third core member 10 is increased. Therefore, it is possible to improve the magnetic efficiency and obtain a high head output.

In the above-described embodiment, the lower specification magnetic head unit 2 and the higher specification magnetic head unit 3 are provided, and the dual-purpose floppy disk enables the lower specification magnetic disk DL and the higher specification magnetic disk DU to be used interchangeably. Although the composite magnetic head 1 mounted on the disk device has been described, the present invention is not limited to such a composite magnetic head 1, and the magnetic disk mounted on a dedicated floppy disk device in which only the upper specification magnetic disk DU is loaded. Of course, a head may be used. Further, the upper specification magnetic head unit 3 is configured by a MIG head in which the magnetic gap 21 is a metal-in-gap, but may be another high density magnetic head, for example, an MR head or a thin film magnetic head. Furthermore, it goes without saying that the shape, dimensions, and the like of each part are not limited to the above-described configuration.

[0066]

As described above in detail, according to the magnetic head of the present invention, the magnetic field generating portion is formed to have substantially the same width as the recording track width of the magnetic disk. Works efficiently, suppresses the rise in head impedance, reduces crosstalk even on magnetic disks that have achieved high-density recording by narrowing track pitch, and provides high-precision information signals. Record and play back.

Further, according to the method of manufacturing a magnetic head of the present invention, the generated magnetic field is efficiently applied to the recording tracks of the magnetic disk, the rise of the head impedance is suppressed, and the track pitch is reduced. Even for a magnetic disk for which high-density recording has been achieved, a magnetic head that records and reproduces information signals and the like with high accuracy by reducing crosstalk can be manufactured with high accuracy by a simple process.

[Brief description of the drawings]

FIG. 1 is a plan view of a composite magnetic head shown as an embodiment of a magnetic head according to the present invention.

FIG. 2 is a side view of a main part of the composite magnetic head.

FIG. 3 is a main part longitudinal sectional view for explaining a configuration of a higher specification magnetic head portion constituting the composite magnetic head, and is a diagram in which a magnetic gap portion is sectioned.

FIG. 4 is a longitudinal sectional view of an essential part for explaining a configuration of the magnetic head unit having the higher specification, and is a sectional view of a recess.

FIG. 5 is a main part plan view for explaining the configuration of the magnetic head unit having the higher specification.

FIG. 6 is a vertical sectional view of a main part for explaining the configuration of the magnetic head unit having the higher specification.

FIG. 7 is a block diagram illustrating a manufacturing process of the composite magnetic head.

FIG. 8 is an explanatory diagram showing a shape of an intermediate in each step of the manufacturing process.

FIG. 9 is a perspective view of a main part of a ferrite block material constituting a material of a core member in the same manufacturing process, showing a state where a convex portion is formed on an upper end surface thereof.

[Explanation of symbols]

1 composite magnetic head, lower specification magnetic head part, 3
Upper specification magnetic head, 4 disk sliding surface, 5 groove, 8 first core member, 9 second core member, 1
0 third core member, 12 reinforcing member, 13 spacer member, 14, 15 slider member, 16 read / write coil, 18 read / write gap, 19
Erase gap, 21 metal in gap,
22 gap forming groove, 23 leg, 24 magnetic metal film, 25 gap forming portion, 26 inclined surface, 27 convex portion, 28 concave portion, 29 molten glass, 31 inner peripheral convex curved surface region portion, 32 outer peripheral convex curved surface region portion, 33 Outer peripheral area,
34 Chamfer, A magnetic disk rotation direction, D magnetic disk, DL lower specification magnetic disk, DU higher specification magnetic disk, O head center, HL head center line, CL third core member center line, TRL upper magnetic disk Center line of recording track, width of recording track of TRW upper magnetic disk, radius of R1 inner convex curved surface area portion, radius of R2 outer convex curved surface region portion, R3 radius of curvature of inner peripheral convex curved surface region portion, R4 outer peripheral convex curved surface Radius of curvature of area

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G11B 5/31 G11B 5/31 E

Claims (8)

[Claims] 1. A magnetic head for recording / reproducing an information signal or the like by holding a magnetic gap formed in a core member in a pseudo contact state with respect to a main surface of a rotationally driven magnetic disk. The disk sliding surface that contacts the main surface of
At least a portion including the magnetic gap formation region is configured as a convex curved surface, and the core member is provided with a protrusion having a width substantially equal to a recording track of the magnetic disk in the magnetic gap formation region. At the same time, the concave portion formed by the convex portion is filled with a non-magnetic material so as to form substantially the same surface as the upper end surface, and the disk sliding surface is formed by the upper end surface of the convex portion and the surface of the non-magnetic material. A magnetic head characterized by comprising: 2. The core member is formed such that a disk sliding surface in the disk rotation direction across the magnetic gap is narrow, and an upper end surface on both side surfaces of the core member is flush with the disk sliding surface. 2. The magnetic head according to claim 1, wherein the reinforcing members formed of the nonmagnetic material are joined to each other. 3. The magnetic head according to claim 1, wherein the magnetic gap forms a metal-in-gap by forming a metal film on a constituent wall thereof. 4. A second core member having a second magnetic gap formed on one side surface thereof through a non-magnetic member, is joined to the core member having the metal-in-gap. 4. The magnetic head according to claim 3, wherein recording / reproduction of an information signal or the like to / from a second magnetic disk having a different recording density of an information signal or the like is performed by the second magnetic gap. 5. The core member according to claim 1, wherein a center of the core member is laterally eccentric with respect to a head center, and a recording track of the magnetic disk is positioned closer to a center of the core member than a head center. The magnetic disk according to claim 1, wherein: 6. The disk sliding surface has a radius L from a head center including at least the magnetic gap forming region.
And a composite convex portion comprising an inner peripheral curved surface portion formed of a convex curved surface having a radius of curvature R1 and an outer peripheral region formed of a convex curved surface having a radius of curvature of R2 which is an outer peripheral region of the inner peripheral curved surface portion. 2. The magnetic head according to claim 1, wherein the magnetic head has a curved surface, and a radius of curvature R1 of the inner curved surface portion and a radius of curvature R2 of the outer curved surface portion satisfy R1> R2. 7. A method of manufacturing a magnetic head for recording / reproducing an information signal or the like while maintaining a magnetic gap formed in a core member in a pseudo contact state with respect to a main surface of a magnetic disk driven to rotate, On the core member, on the upper end surface forming the disk sliding surface, leaving the area where the magnetic gap is formed as a convex part having substantially the same width as the recording track, and cutting the other area as a concave part; A step of filling the cut recess with a nonmagnetic material so as to form substantially the same surface as the upper end face of the magnetic gap forming region convex portion; and a process comprising filling the magnetic gap forming region convex portion and the nonmagnetic material. Grinding the surface to make the disk sliding surface a convex curved surface. 8. A step of forming a narrow disk sliding surface in the disk rotation direction sandwiching the magnetic gap with respect to the core member, and forming an upper end surface on both side surfaces of the core member in the disk rotation direction. 8. A method for manufacturing a magnetic disk according to claim 7, wherein a step of joining reinforcing members formed of a nonmagnetic material forming the same surface as the disk sliding surface is performed.