JP2000149216A - Magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the positional precision and relative azimuth precision between a magnetic head part for a high capacitance and a magnetic head part for a low capacitance and to maintain the reduction of gap loss in a magnetic circuit of the magnetic head part for a low capacitance. SOLUTION: In this magnetic head 50, a magnetic head part 52 for a low capacitance is connected to a magnetic head part 51 for a high capacitance via a slider 53, and writing/reading to/from a magnetic recording medium are executed. In such a case, in the lower end of core members 52a, 52b, 52c of the magnetic head part 52 for a low capacitance, a back bar 60 which connects a magnetic circuit is connected to the surface different from the side facing the slider 53, a connecting surface 52e between the magnetic head part 52 for a low capacitance and the back bar 60 is also lapped, and a connecting surface between the magnetic head part 52 for a low capacitance and the slider 53 is polished.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite magnetic head provided with a low-capacity magnetic head and a high-capacity magnetic head.

[0002]

2. Description of the Related Art Conventionally, a floppy disk drive which has been used as one of the basic information recording devices of a personal computer has a storage capacity of 720 k of the floppy itself.
Since B is as small as about 1.44 MB and the information reading speed is slow, various attempts have been made to develop a high capacity drive other than a floppy disk drive. Against this background, in recent years, the development of a magnetic recording device that has compatibility with floppy disks and allows the use of disks with much higher capacities than floppy disks, and that can read and write information at high speed. Is being promoted.

The magnetic head device shown in FIGS. 11 to 14 is an example of a magnetic head device for a high-capacity drive of this type which is compatible with a floppy drive. A triangular plate-shaped load beam 2 is connected to a fixed mount 1 connected to a drive drive mechanism of the apparatus, and a mounting mount 3 is provided at the tip of the load beam 2. A gimbal suspension member 4 mounted on the mounting mount 3 , The magnetic head slider 5 is mounted. As shown in FIGS. 12 to 14, a composite magnetic head in which a high-capacity magnetic head portion H1 and a low-capacity magnetic head portion H2 are integrated, as shown in FIGS. Is incorporated.

FIGS. 12 to 14 show a high-capacity magnetic head H1 and a low-capacity magnetic head H2. The high-capacity magnetic head H1 and the low-capacity magnetic head H2 are connected to each other. Are connected by a nonmagnetic slider H3. The slider H3 has an air bearing portion H31 for holding a head portion H1 for high capacity, and an air bearing portion H31.
And a connection portion H32 that protrudes from the connection portion and holds a low-capacity magnetic head portion H2. Here, the low-capacity magnetic head portion H2 is assembled to a substantially E-shaped core by combining the center I-shaped bar H22 and the L-shaped bars H21 and H23 on both sides, and is attached to the I-shaped bar H22 and the L-shaped bar. Bar H21, H2
Gaps G1 and G2 are formed at the joints with
A back bar H4, which bridges the I-shaped bar H22 and the L-shaped bars H21, H23, is provided on the side of the bar member H21, H22, H23 that constitutes the lower portion of each bar member, facing the slider H3. A magnetic circuit having a magnetic gap G1 is formed by the I-type bar H22, the one L-type bar H21, and the back bar H4, and the magnetic gap G2 is formed by the I-type bar H22, the other L-type bar H23, and the back bar H4. Having a magnetic circuit.

Here, an allowable range of a position setting error in connection between the high-capacity magnetic head H1 and the low-capacity magnetic head H2 is set based on the information writing density of a high-capacity disk. The allowable range of the position setting is ± 10 μm to ± 20 μm or less, and the parallel state of the two heads is defined by a standard of an error range of 20 minutes or less. The operational reliability of this type of composite magnetic head device is determined by the positions of these two heads. Therefore, when connecting the slider H3 to the low-capacity magnetic head H2, the accuracy must be satisfied. . When connecting the low-capacity magnetic head H2 and the back bar H4,
In this connection surface, there is a possibility that a gap loss which reduces the magnetic efficiency in the above-described magnetic circuit may occur. Conventionally, in order to reduce the gap loss in this magnetic circuit, these connection surfaces are wrapped by a lap device. Lapping was used to reduce the roughness of the connection surface.

[0006] Here, the polishing is a process in which a grindstone or a grinding wheel having abrasive grains formed into a predetermined shape by a binder is moved with respect to a processing surface to be processed, and the processing surface is polished. It is a processing method and the surface roughness remains,
The thickness deviation of the processed surface is a high processing method. In addition, lapping is a process in which a lapping material composed of abrasive grains and a working fluid is injected between a soft tool called a lap formed into an ideal finished shape of the surface of a workpiece to be machined and a workpiece, and a pressure is applied. This is a precise surface finishing method in which the surface of the workpiece is sharpened into the shape of a lap by relative motion while sliding them mutually with each other.

[0007]

However, the connection surface H5 of the low-capacity magnetic head portion H2 with the back bar H4 is lapped, but the lapping is more effective than the polishing. Although the particle size of the material is small and the surface roughness of the treated surface is low and the mirror surface treatment is possible, the lapping process accumulates when the wrap material enters between the wrap and the treated surface,
As the peripheral edge of the processing surface is further polished, the peripheral edge of the processing surface may be curved, and as described above, the peripheral edge of the connection surface H5 may be curved as shown by R in FIG. When the slider H3 is connected to the low-capacity magnetic head H2, the accuracy of setting these positions may be reduced. Therefore, there is a problem that the positional accuracy and the relative azimuth accuracy of the high-capacity magnetic head unit H1 and the low-capacity magnetic head unit H2 decrease, and the product yield of the magnetic head device decreases.

The present invention has been made in view of the above circumstances, and has an object to achieve the following objects. To improve the positional accuracy and relative azimuth accuracy of the high-capacity magnetic head and the low-capacity magnetic head. To reduce gap loss in a magnetic circuit of a low-capacity magnetic head unit.

[0009]

SUMMARY OF THE INVENTION The present invention comprises a first magnetic head and a second magnetic head, wherein the magnetic heads are connected via a slider to write data on a magnetic recording medium. / Reading, and at least one of a connection surface of the slider connected to the first magnetic head portion and a connection surface of the first magnetic head portion connected to the slider. The above problem was solved by making the surface a polished surface. By polishing the connecting surface between the first magnetic head portion and the slider, it is possible to prevent the peripheral portion of the connecting surface from being curved. Therefore, the position setting at the time of joining the first magnetic head unit and the slider, that is, the positional accuracy and relative azimuth accuracy between the first magnetic head unit and the second magnetic head unit via the slider are improved. be able to.

Here, the connection surface of the slider connected to the first magnetic head portion and the connection surface of the first magnetic head portion connected to the slider are polished surfaces. More preferred. By making these two connection surfaces a polished surface and connecting these polished surfaces,
The positional accuracy and relative azimuth accuracy of the first magnetic head and the second magnetic head can be further improved.

In the present invention, the first magnetic head portion is provided with a core on which a plurality of bars are assembled, and a back bar bridging the bars, and the back bar connected to the core is provided. And a connection surface of at least one of the connection surfaces of the core connected to the back bar may be employed. Further, in the present invention, the first magnetic head portion is assembled to a substantially E-shaped core by combining a central I-shaped bar and L-shaped bars on both sides, and the I-shaped bar and the L-shaped bar are combined. A gap is formed at each joint portion of the back bar, a back bar bridging the I-bar and the L-bar is provided, and a connection surface of the back bar connected to the core; It is also possible to employ means in which at least one of the connection surfaces of the core portion connected to the core portion is a lapping surface. The first
In the magnetic head portion, the connection surface between the back bar and the core is lapped to reduce the roughness of this connection surface without reducing the thickness deviation of the connection surface connecting the slider, and the back bar and the core In the core of the first magnetic head portion, the magnetic loss formed in the magnetic circuit formed by the I-type bar, the L-type bar, and the back bar is reduced by improving the close contact state of the connection surface of the first magnetic head portion. be able to.

Further, in the present invention, it is preferable that the back bar is connected to a surface of the core of the first magnetic head portion which is different from one surface of the core facing the slider. In the core of the first magnetic head portion, the back bar is connected to a surface different from the side facing the slider, so that the connection surface for connecting the slider can be a polished surface, and the slider is connected. It is not necessary to lap the surface to be connected, so the connection surface between the back bar and the first magnetic head portion is wrapped without reducing the thickness deviation of the connection surface to which the slider is connected, and Roughness can be reduced.

Further, in the present invention, a first magnetic head unit and a second magnetic head unit are provided, and the magnetic head units are connected to each other via a slider to perform writing / reading on a magnetic recording medium. In the first magnetic head portion, a central I-shaped bar and L-shaped bars on both sides are combined and assembled into a substantially E-shaped core, and each of the I-shaped bar and the L-shaped bar is provided. Gaps are formed at the joining portions of the I-shaped bar and the L-shaped bar,
A back bar bridging these is connected to a surface different from the side facing the slider, and a connection surface of the back bar connected to the core and a connection surface of the core connected to the back bar are included. Alternatively, a means in which at least one connection surface is a lapping surface may be employed. In the first magnetic head portion, the back bar is connected to a surface different from the side facing the slider, so that the connection surface for connecting the slider can be a polished surface and is connected to the back bar. The connection surface of the first magnetic head portion is lapped to reduce the thickness deviation of the connection surface of the first magnetic head portion connected to the slider. The roughness of the connection surface of the core of the magnetic head portion is reduced, and more preferably, the connection surface of the back bar connected to the first magnetic head portion is lapped to form a connection surface of the back bar. By connecting the lapping surfaces to each other, the first
Gap loss in the magnetic circuit of the magnetic head unit can be further reduced.

[0014] More preferably, a means may be employed in which the connection surface of the back bar connected to the core and the connection surface of the core connected to the back bar are lapping surfaces. By making both connection surfaces of the core and the back bar lapping surfaces, a connection surface between the back bar and the first magnetic head portion is wrapped to further reduce the roughness of the connection surface. can do. Here, it is possible that the first magnetic head is a magnetic head for low capacity and the second magnetic head is a magnetic head for high capacity.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a magnetic head according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a state in which the magnetic head of the present invention is mounted on a magnetic head device, and FIG. 2 is a plan view showing a state in which the magnetic head shown in FIG. 1 is mounted on the magnetic head device. 1 and 2, reference numeral 31 denotes a magnetic head unit, and reference numeral 50 denotes a magnetic head.

The magnetic head of this embodiment is mounted on a magnetic head device shown in FIG. 1. The magnetic head device includes a magnetic head unit 31 and an elongated triangular plate-shaped load beam 32 for supporting the magnetic head unit 31. The base plate 3 provided on the base end side of the load beam 32
3 and is configured such that the magnetic head unit 31 can be moved with respect to the magnetic recording medium by attaching the base plate 33 to a drive device for the magnetic recording medium. The magnetic head device of this embodiment incorporates a high-capacity magnetic head unit and a low-capacity magnetic head unit, which will be described later. The low-capacity magnetic head unit has a capacity of 1 MB to 2 MB. The floppy disk is used as a magnetic recording medium and slides with respect to the floppy disk.The high-capacity magnetic head has a higher capacity than the floppy disk in a case of approximately the same size as the floppy disk. (Eg 1
A magnetic recording medium containing a 20 MB or 200 MB disk is used to record and reproduce magnetic information while sliding or floating on the magnetic recording medium.

As shown in FIGS. 1 and 2, the magnetic head unit 31 has a hollow rectangular frame-shaped mounting mount 35.
And a plate-shaped gimbal member 3 attached to the opening.
6 and a magnetic head 50 attached to the center of the gimbal member 36 on the bottom side.

As shown in FIGS. 1 and 2, the gimbal member 36 has a single plate shape, and includes an outer frame body 40 on the outer periphery thereof and an inner frame body 41 disposed inside thereof. , And an inner plate 42 arranged inside the plate. In the gimbal member 36, the inner frame 41 is supported via outer bridges 43, 43 formed at coaxial positions on one side and the other side of the inner peripheral portion of the outer frame 40. Inner bridges 45, 45 are formed at coaxial positions substantially orthogonal to the positions where the outer bridges 43, 43 are formed.
5, the inner plate 42 is supported inside the inner frame 41. Here, the four corners of the outer frame body 40 are fixed to the corners of the frame-shaped mounting mount 35, and the inner plate 42 is connected to the outer bridges 43, 43 inside the opening of the mounting mount 35. Bridge 4
5 and 45 are suspended.

FIG. 3 is a perspective view showing the magnetic head of this embodiment, FIG. 4 is a plan view thereof, FIG. 5 is a side view thereof, FIG. 6 is a front view thereof, and FIG. 7 is a side view thereof. The magnetic head 50
As shown in FIGS. 2 to 7, a high-capacity magnetic head unit (second magnetic head unit) 5 provided on one side in the width direction.
1; a low-capacity magnetic head (first magnetic head) 52 provided on the other side in parallel with the high-capacity magnetic head 51; and a slider 53 connecting these. . A slider 53 made of a non-magnetic material such as Al ₂ O ₃ .TiC (aluminum titanium carbide) and Ca.TiO ₂ (calcium titanate) holds a high-capacity magnetic head 51 facing a magnetic medium. It has an air bearing portion 53a and a connection portion 53b for connecting the air bearing portion 53a and the magnetic head portion 51 for high capacity and the magnetic head portion 52 for low capacity. The medium facing surfaces of the magnetic heads 52 and 53 also function as medium sliding surfaces or air bearing surfaces. The slider 53 and the low-capacity magnetic head 52 are connected to a connection surface 53d of the slider 53 polished by polishing and a connection surface 52d of the low-capacity magnetic head 52, which will be described later, with an adhesive glass or the like. Is glued through.

As shown in FIGS. 2 to 6, the high-capacity magnetic head 51 is made of a core member 51 made of a magnetic material.
a and 51b are joined via a gap material to form a magnetic gap G3, and grooves 51c and 51c filled with a non-magnetic material are provided on both sides of the magnetic gap G3 to regulate a track width. A winding hole 51d is provided on the side wall surface of 53a, and is embedded in the air bearing portion 53a. The core members 51a and 51b are
A magnetic circuit having a magnetic gap G3 is formed in a substantially ring shape so as to surround the winding hole 51d.

As shown in FIGS. 2 to 7, the low-capacity magnetic head 52 is an I-shaped core member (bar) at the center.
L-shaped core members (bars) 52b, 52c on both sides of 52a
Are assembled to a substantially E-shaped core through magnetic gaps G1 and G2 between the core members 52a and 52a, respectively.
As shown in FIG. 2, a through hole 54A through which the b and 52c can be inserted is formed at the center of the inner plate 42 of the gimbal member 36, and the core member 52 is inserted through the through hole 54A.
The magnetic heads 51 and 52 are attached to the gimbal member 36 by inserting the a, 52b, and 52c into the inside of the mounting mount 35 and fixing the connecting portion 53b to the internal plate 42 by a fixing means such as an adhesive. . Further, the high-capacity magnetic head portion 51 has the lower portions of the core members 51a and 51b and the lower portion of the air bearing portion 53a inserted into the through holes 54B formed in the inner plate 42, and then the high-capacity magnetic head portion 51 has been inserted. It is attached to the inner plate 42 together with the connection portion 53b.

In the low-capacity magnetic head section 52, the distal ends of the core members 52a, 52b, and 52c penetrating the internal plate 42 and inserted into the inside of the mounting mount 35 are formed so as to bridge them. I type back bar 60
As shown in FIGS. 3 to 7, a connecting surface 52 connected to a high-capacity magnetic head 51 via a slider 53 is provided.
It is provided on the connection surface 52e on the opposite side to d. In the low-capacity magnetic head unit 52 of this embodiment, a connection surface 52d for connecting the high-capacity magnetic head unit 51 via the slider 53 is a polished surface.
The connection surface 52e on the side opposite to d is a lapping surface. FIG. 8 is a front view showing the mounted state of the magnetic head 50 and the back bar 60. As shown in FIGS. 7 and 8, the connecting surface of the back bar 60 is pressed against the core members 52a, 52b, and 52c by an elastic clip member 62 in order to reduce a gap loss of a magnetic circuit described later. I have. The central portion of the back bar 60 is divided by an insulator 61, and the insulator 61 and the core member 52a,
A magnetic circuit having a magnetic gap G1 between the core members 52a and 52b is formed.
2 is formed. In the back bar 60, a connection surface 60e connected to the low-capacity magnetic head unit 52 is a lapping surface. here,
The back bar 60 includes core members 52a, 52 shown in FIG.
It is also possible to connect to the end face 52f on the lower end side of b, 52c. At this time, the back face 60 is connected by lapping the end face 52f.

As shown in FIG. 7, in the low-capacity magnetic head section 52, a rectangular cylindrical bobbin 63 inserted through the core members 52b, 52c is provided at the tip end side of the core members 52b, 52c. , 63 are provided, and the bobbins 63, 63 are wound with coils to form coils. Next, in the high-capacity magnetic head section 51, similarly to the low-capacity magnetic head section 52, the core members 51a,
A coil winding is applied to a winding hole 51d formed at a boundary portion of 51b to form a coil. The windings of these coils are drawn out as a plurality of connection wirings,
As shown in (1), these connection wirings are gathered and pulled out as stranded lead wires 90 and 91.

Next, the magnetic head 50 according to the present embodiment will be described.
Will be described. 9 and 10 are manufacturing process diagrams of the magnetic head 50 according to the present embodiment. In the magnetic head 50, a high-capacity magnetic head unit 51 and a low-capacity magnetic head unit 52 are manufactured and connected.

The L-shaped core members 52b and 52c are joined to the I-shaped core member 52a, and then cut and cut to have substantially the same shape as the low-capacity magnetic head 52. Head core.

Thereafter, as shown in FIG. 9, in the head core having substantially the same shape as the low-capacity magnetic head 52, a connection surface 52d for connecting to the high-capacity magnetic head 51 via the slider 53 is provided. Is subjected to a surface treatment by polishing, and as shown in FIG. 10, a connection surface 52e for connecting to the back bar 60 is subjected to a surface treatment by lapping to manufacture a magnetic head portion 52 for low capacity.

Next, as shown in FIG. 9, the low-capacity magnetic head 52 and the high-capacity magnetic head 51 integrally formed with the slider 53 are connected to the connecting surface 53d of the slider 53 and the low-capacity magnetic head. To the connection surface 52d of the magnetic head 52 for use with an adhesive glass or the like. Along with this, FIG.
As shown in FIG. 0, after the back bar 60 is subjected to a lapping process as a surface treatment on a connection surface 60e for connecting to the connection surface 52e, the back bar 60 is attached to a low-capacity magnetic head unit. 52, and is connected to the connection surface 52e and clipped. Thereafter, a predetermined coil winding or the like is performed to complete the magnetic head 50.

According to the magnetic head 50 of this embodiment, when the back bar 60 is connected to the low-capacity magnetic head 52, the connection surface 52e of the low-capacity magnetic head 52 and the back bar 60 are connected. After lapping the surface 60e with a lapping surface, the low-capacity magnetic head 52 is moved to the high-capacity magnetic head 51 via the slider 53.
Surface 52d of low-capacity magnetic head 52 for connecting
The connection surface 60e of the back bar 60 is connected to a different surface, more preferably, the connection surface 52e. Therefore, the adhesion between the back bar 60 and the low-capacity magnetic head 52 is improved through the connection surfaces 52e and 60e, which have been lapped to reduce the roughness of the surface to reduce the roughness. The occurrence of gap loss can be prevented. In addition, the connection surface 52d of the low-capacity magnetic head unit 52 for connecting the high-capacity magnetic head unit 51 and the connection surface 53d of the slider 53 are polished to improve plate thickness deviation. The periphery of the connection surface 52d can be prevented from becoming curved.

Here, an example of a comparison between a surface that has been surface-treated by polishing and a surface that has been surface-treated by lapping will be described below. Lapping is a process in which diamond abrasive grains and a lubricant having a particle size of about 1 μm to 2 μm are supplied to the upper surface of a rotating lapping surface plate and one surface of a block made of ferrite is pressed against the lapping surface plate. Table 1 shows numerical values obtained by measuring the surface roughness and plate thickness deviation of the processed surface. In the polishing process, a ferrite block is fixed on a rotating table, and is ground by a diamond wheel (grain size # 400 to # 1000) rotating from above, and the surface roughness and thickness deviation of the processed surface are determined. Table 1 shows the measurement results.

[0030]

[Table 1]

As described above, the connection surface 52d of the low-capacity magnetic head 52, which connects the high-capacity magnetic head 51 via the slider 53, is subjected to a surface treatment by polishing with a thickness deviation of 2 μm or less. This prevents the peripheral portion of the connection surface 52d from being curved. Accordingly, the connection between the high-capacity magnetic head 51 and the low-capacity magnetic head 52 via the slider 53 is ± 10 μm.
An allowable range of the position setting error of ± 20 μm or less, and two magnetic heads 51 and 52 of 20 minutes or less.
Can be connected satisfying the error range of the parallel state of
The effect that the operation reliability of the magnetic head device can be ensured can be achieved.

The connecting surface 52e of the low-capacity magnetic head 52 for connecting the back bar 60 is
By performing mirror finishing by lapping of about mRa, the core members 52a, 52a,
Adhesion between the back bars 60 and 52b, 52c can be improved. Thereby, the I-shaped core members 52a, L
In the magnetic circuit having the magnetic gap G2 formed by the mold core member 52b and the back bar 60, the occurrence of gap loss can be reduced, and the I-shaped core member 52a, the L-shaped core member 52c, and the back bar 60 can be reduced. In the magnetic circuit having the magnetic gap G1 formed as described above, the occurrence of gap loss can be reduced, and the magnetic efficiency in the magnetic circuit can be prevented from being reduced. Therefore, the size of the magnetic head can be increased. Therefore, the output of the magnetic head can be increased.

[0033]

According to the magnetic head of the present invention, the following effects can be obtained. (1) First magnetic head (magnetic head for low capacity)
By polishing the connecting surfaces of the slider and the slider, the peripheral edges of these connecting surfaces are prevented from being curved, and the position setting at the time of joining the low-capacity magnetic head unit and the slider is performed, that is, Thus, the positional accuracy and relative azimuth accuracy of the high-capacity magnetic head unit and the low-capacity magnetic head unit via the slider can be improved. (2) First magnetic head (magnetic head for low capacity)
In the above, the back bar is connected to the surface of the core different from the side to which the slider is connected, so that the back bar and the magnetic head for low capacity are formed by lapping without reducing the thickness deviation of the connecting surface to which the slider is connected. It is possible to reduce the roughness of the connection surface with the unit, and reduce the gap loss in the magnetic circuit of the low-capacity magnetic head unit.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a magnetic head device according to an embodiment of the present invention when mounted on a magnetic head device.

FIG. 2 is a plan view showing a state where the magnetic head shown in FIG. 1 is mounted on a magnetic head device.

FIG. 3 is a perspective view showing the magnetic head shown in FIG. 1;

FIG. 4 is a plan view showing the magnetic head shown in FIG. 3;

FIG. 5 is a side view showing the magnetic head shown in FIG. 3;

FIG. 6 is a front view showing the magnetic head shown in FIG. 3;

FIG. 7 is a side view showing the magnetic head shown in FIG. 3;

8 is a front view showing a state in which the magnetic head shown in FIG. 3 is mounted on the magnetic head device and a state in which the back bar is mounted.

FIG. 9 is a manufacturing process diagram of the magnetic head according to the embodiment.

FIG. 10 is a manufacturing process diagram of the magnetic head according to the embodiment.

FIG. 11 is a perspective view showing a state in which a conventional magnetic head is mounted on a magnetic head device.

FIG. 12 is a perspective view showing a conventional magnetic head.

FIG. 13 is a plan view showing a conventional magnetic head.

FIG. 14 is a front view showing a conventional magnetic head.

[Explanation of symbols]

Reference numeral 50: magnetic head, 51: second magnetic head (high-capacity magnetic head), 52: first magnetic head (low-capacity magnetic head), 53: slider, 53a
Air bearing part, 53b ... connection part, 51a, 51b
... Core members (bars), G1, G2, G3 ... magnetic gaps, 51c ... grooves, 51d ... winding holes, 52a, 52
b, 52c: core member, 52d, 52e, 53d, 6
0e: connection surface, 54A: through-hole, 60: back bar, 6
1. Insulator 62. Clip member

Claims (8)

[Claims] A first magnetic head unit; and a second magnetic head unit, wherein the magnetic head units are connected to each other via a slider, and perform writing / reading on / from a magnetic recording medium. At least one of the connection surface of the slider connected to the first magnetic head portion and the connection surface of the first magnetic head portion connected to the slider is a polished surface. A magnetic head, characterized in that: 2. The polishing machine according to claim 1, wherein a connection surface of said slider connected to said first magnetic head portion and a connection surface of said first magnetic head portion connected to said slider are polished surfaces. The magnetic head according to claim 1, wherein 3. The first magnetic head portion includes a core on which a plurality of bars are assembled, and a back bar bridging the bars, and a connection of the back bar connected to the core. The magnetic head according to claim 1, wherein at least one of a surface and a connection surface of the core connected to the back bar is a lapping surface. 4. The first magnetic head section has a central I
The mold bar and the L-shaped bars on both sides are combined and assembled into a substantially E-shaped core, and a gap is formed at each joint between the I-shaped bar and the L-shaped bar. A back bar that bridges them is provided, and a connection surface of the back bar connected to the core, and a connection surface of the core portion connected to the back bar,
3. The magnetic head according to claim 1, wherein at least one connection surface is a lapping surface. 5. The magnetic head according to claim 3, wherein the back bar is connected to a surface of the core of the first magnetic head portion, the surface being different from one surface of the core facing the slider. 6. A system comprising a first magnetic head unit and a second magnetic head unit, wherein the magnetic head units are connected to each other via a slider, and perform writing / reading to / from a magnetic recording medium. In the first magnetic head portion, a central I-shaped bar and L-shaped bars on both sides are combined and assembled into a substantially E-shaped core, and a joint portion between each of the I-shaped bar and the L-shaped bar is provided. At the lower end of each of the I-shaped bar and the L-shaped bar, a back bar bridging them is connected to a surface different from the side facing the slider, and the back bar connected to the core is formed. And a connection surface of the core connected to the back bar is a lapping surface. 7. The lapping surface of a connection surface of the back bar connected to the core and a connection surface of the core connected to the back bar.
6. The magnetic head according to any one of items 1 to 5. 8. The apparatus according to claim 1, wherein said first magnetic head section is a low-capacity magnetic head section, and said second magnetic head section is a high-capacity magnetic head section. 8. The magnetic head according to any one of 7.