JPH05135322A - Composite type magnetic head - Google Patents

Abstract

PURPOSE:To constitute a small-sized and lightweight magnetic head for driving a floppy disk with ease of assembly. CONSTITUTION:A composite magnetic core 10 combined with a recording and reproducing core 11 and an erasing core 12 is fixed to a slider 20. A recording and reproducing coil assembly 50 and an erasing assembly 51 are built cooperatively with the above-mentioned composite magnetic core 50 in this slider 20. Back cores 40, 41 are fixed to the open end of the composite magnetic core 60 in tight contact therewith. The slider 20 is obtd. by injection molding of ceramics and has nearly a box shape in order to house the core and coil assemblies. The slider 20 further includes both side walls and an end wall lower in height than these walls. Noses 24, 25 expanding toward a core slit 21 are provided on these two side walls and further, housing part for housing back cores 40, 41 are provided in a part of these noses 24, 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite type magnetic head, and more particularly to a slider structure of a magnetic head in which a recording / reproducing and erasing head used in a floppy disk drive is combined.

[0002]

2. Description of the Related Art In order to perform recording / reproduction of a magnetic recording medium, for example, a floppy disk, a composite type magnetic head in which a recording / reproducing head and an erasing head are combined is used, and with the miniaturization of a floppy disk drive, This magnetic head is also required to have a compact and precise structure.

A magnetic head generally known as a bulk type head includes a ceramic slider that is in sliding contact with the recording surface of a magnetic recording medium and a gimbal spring that supports the slider on a carriage arm. The slider has a recording / reproducing gap and an erasing gap. A composite magnetic core for forming, a recording / reproducing coil assembly attached to the magnetic core, an erasing coil assembly, and a back core magnetically closing an open end of the magnetic core are incorporated.

In such a composite type magnetic head, a manufacturing error of the head itself causes variations in dynamic characteristics during recording and reproduction, which impairs compatibility with other devices.
It must be manufactured with a high degree of precision and easily, and the mass of the head itself must be small in order to move following the recording surface of the floppy disk and to have sufficient strength against external impacts. Since the floppy disk is mounted on the portable computer, there is a demand that magnetic efficiency must be increased in order to reduce the current consumption.

Conventionally, in order to meet such various demands, various improvements have been made to this type of composite magnetic head.

An example of such a conventional apparatus is Japanese Patent Laid-Open No. 62-62
-214511 and JP-A-62-217413,
Disclosed as an integrated magnetic head suitable for a floppy disk drive, the magnetic head includes a casing slider made of non-magnetic ceramics having a substantially rectangular parallelepiped outer shape, and a read / write core and an erase core are integrally formed in a recess of the casing slider. A magnetic head core that is specially provided is inserted, and the tip of this magnetic head core penetrates an insertion opening provided in the slider and is exposed to the magnetic recording medium side.

Therefore, according to this conventional apparatus, it is possible to obtain a lightweight magnetic head having a small number of parts and easy to assemble.

Further, the inventor of the present invention has disclosed in Japanese Patent Laid-Open No. 3-212810.
As a result, a composite magnetic head was proposed, and with this magnetic head, a structure capable of positioning and fixing the core at a correct position with respect to the slider was disclosed. According to this conventional device, the core chip holding hole provided in the slider is provided with a plurality of protrusions, and when the composite core chip is bonded in the core chip holding hole, the plurality of protrusions reliably guide the core chip. Can be fulfilled.

Further, as described above, in order to improve the magnetic efficiency of the magnetic head, the open end of the composite core needs to be magnetically closed by the back core.
Several proposals have been made to bring the composite core and the back core into close contact with each other.

As such a conventional technique, for example, Japanese Patent Laid-Open No. 61-165811 or Japanese Utility Model Publication No. 3-16092 is known. In both cases, a coil bobbin is provided with a pressing portion or a claw portion, and a composite core and these pressing portions are provided. Alternatively, the back core is sandwiched between the claws.

Therefore, according to such a conventional device, the adhesion between the composite core and the back core can be improved, the magnetic resistance can be reduced, and the magnetic efficiency at the time of recording / reproducing or erasing can be improved to increase the current consumption. Can be reduced.

[0012]

However, in these conventional devices, it is not possible to obtain a highly precise head, and particularly when the slider is formed by injection molding, distortion occurs in each part of the slider, Alternatively, it may be deformed, and there is a problem that the yield of the product is reduced, which is difficult to realize.

In particular, the above-mentioned JP-A-62-214511.
In the conventional apparatus disclosed in Japanese Patent Laid-Open No. 62-217413 and Japanese Patent Laid-Open No. 62-217413, the core and coil assembly must be housed in a substantially rectangular parallelepiped slider, which results in a large head size. However, it was difficult to put it into practical use as a slider for an actual composite magnetic head.

Further, the conventional Japanese Patent Laid-Open No. 3-2 by the present inventor.
No. 12810 has a drawback that the strength of the slider may not be sufficient and that it takes time to bond the gimbal spring or the composite core and the back core.

The present invention has been made in view of the above conventional problems, and an object thereof is to provide a composite magnetic head having a small number of parts, a small size and a light weight, excellent assembling property, and good magnetic efficiency. ..

[0016]

In order to achieve the above object, the present invention provides a composite magnetic core comprising a recording / reproducing core and an erasing core, and the composite magnetic core fixedly supported and slidably contacting a magnetic recording medium. A recording / reproducing coil assembly having an integral slider, a recording / reproducing coil through which the core leg of the recording / reproducing core penetrates, and a bobbin holding the recording / reproducing coil, and an erasing coil through which the core leg of the erasing core penetrates,
A composite magnetic head comprising: an erase coil assembly having a bobbin holding the erase coil; a back core magnetically closing an open end of the composite magnetic core; and a gimbal spring to which the slider is adhesively fixed. The slider has a core slit for exposing and fixing the composite magnetic core to the magnetic recording medium side, a side wall along the longitudinal direction, and a narrow first side wall that is adhesively fixed to a gimbal spring. A second side wall, first and second end walls which are ends along the lateral direction and which are lower in height than the side walls and can accommodate a part of the bobbin on the walls; and the first side wall. A first nose extending from substantially the center in the core slit direction to prevent the composite magnetic core from collapsing, and a second nose extending from the center of the second side wall to the core slit direction to prevent the composite magnetic core from collapsing. And a back core accommodating portion provided on each of the noses, and a meat removing portion provided on both sides of the first nose of the first side wall for equalizing shrinkage during injection molding between both side walls. It is characterized in that it is formed by injection molding of ceramics.

Further, according to the present invention, the slider has a main sliding contact surface provided on the sliding contact surface with the magnetic recording medium around the core slit, and an auxiliary sliding contact provided symmetrically with the main sliding contact surface. And a sliding contact surface facing each other and having a plateau shape that forms an elongated half-moon shape.

[0018]

Therefore, according to the present invention, the slider of the composite magnetic head can be manufactured by injection molding of ceramics,
Moreover, by precisely making this slider, it becomes possible to provide a magnetic head having a high recording density and excellent magnetic efficiency.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of a composite magnetic head according to the present invention, in which the gimbal spring is omitted. The head assembly state of FIG. 1 is further shown in FIG. 2, and FIG. 3 shows a state in which the inside thereof is partially seen through. Further, FIG. 4 shows a perspective view as seen from the gimbal side in the assembled state. FIG. 5 is a plan view seen from the back side of the slider.

In this embodiment, the composite magnetic core 10 provides an integrated composite magnetic core consisting of a recording / reproducing core 11 and an erasing core 12. The both cores 11 and 12 include outer cores 13 and 14 penetrating the coils and inner cores 15 and 16 for closing magnetic flux.
As well known, 5 and 16 are integrally fixed by a glass adhesive. Of course, although not shown in detail in FIG. 1, the recording / reproducing gap 18 and the erasing gap 19 of both cores 11 and 12 allow a magnetic recording medium such as a floppy disk to perform a desired recording / reproducing action. Such a core 11,
12 is preferably formed from a highly magnetically permeable material such as ferrite in the examples.

In the present invention, an integral slider 20 is provided in order to firmly fix and hold the composite magnetic core 10. This integral slider 20 is formed by injection molding ceramics such as calcium titanate in the embodiment. Are configured. The slider 20 is provided with a core slit 21 for exposing the gaps 18 and 19 of the composite magnetic core 10 to the sliding contact surface of the slider 20.
On the side surface in the longitudinal direction of the slider 20, there are provided a wide first side wall 22 and a narrow second side wall 23 parallel to the core slit 21, and the back ends of these side walls 22, 23, that is, FIG. By securely fixing the upper end of the slider to the gimbal spring 42 shown in FIG. 6, a reliable connection between the slider 20 and the gimbal spring 42 can be obtained.
The core slit 21 is formed at the center of both side walls 22 and 23.
When the composite magnetic core 10 is fixed to the slider 20, these noses 24 and 25 prevent the core 10 from collapsing and the core 10 is correctly positioned and fixed to the slider 20. can do. As is well known, the core 10 is fixed to the core slit 21 by using sealing glass or the like, and the noses 24 and 25 firmly position the core 10 with respect to the slider 20 at a predetermined position when the glass is melted. Is useful for doing.

As shown in FIGS. 1 and 6, the back ends of both the noses 24 and 25 are back core storage portions 26 and 2, respectively.
A step is provided as 7. Therefore, as will be described later, the back cores are stored in the storage portions 26 and 27, and the core 10 and the coil assembly and the back core described later can be sufficiently stored in the slider 20.

Surfaces 28 and 29 slightly recessed from the rear end surfaces of the first side wall 22 and the second side wall 23 are formed on the further rear end sides of the noses 24 and 25, respectively.
8 and 29 form a paste gap of silver paste as required, and in the embodiment, the concave surface 28 on the first side wall 22 side.
Apply silver paste to the gimbal spring 4 as described below.
2 and the slider 20 are directly adhered and fixed, whereby the vibration or squeal phenomenon occurring between the gimbal spring and the slider 20 is surely prevented.

On the other hand, the second side wall 2 forming the nose 25 on the side of the second side wall 23 and the back core housing portion 27 connected to the nose 25.
The protrusion protruding from 3 toward the core slit 21 side reliably prevents the sliders 20 from being entangled with each other when the slider 20 is barrel processed from the injection-molded blank state. That is, a plurality of injection-molded blank sliders 20 are inserted into barrels and barrel processed. At this time, the first or second sliders 20 of the sliders 20 are inserted into the gaps existing between the side walls 22 and 23 of the sliders 20. Side wall 2
In order to prevent such a situation, in this embodiment, the back core housing 27 provided on the upper surface of the nose 25 is purposely provided with the core slit 21 in order to prevent such a situation. Overhanging to the side prevents entanglement of the slider 20 during barrel processing.

On the other hand, the short side wall 30 of the slider 20,
Reference numeral 31 has a height shorter than that of the first side wall 22 and the second side wall 23, and as will be apparent from the description below, the terminal receiving portion provided on the bobbin of the coil assembly is escaped on this wall to reduce the size of the device. The weight can be reduced. However, in the conventional structure in which the end walls 30 and 31 on the short side are completely removed, cracks may occur during assembly of the slider 20 or during heat treatment, and as a result, the slider 2
I had to increase the thickness of the sliding contact surface of 0,
In the present invention, by giving a relatively large height to the short side end walls 30 and 31, the strength of the slider 20 is taken over by the short side end walls 30 and 31, and cracks and the like as in the conventional case occur. It was possible to construct a small and lightweight slider 20 which has a thin sliding contact surface thickness.

In this embodiment, the slider 20 is used as a double-sided head capable of recording and reproducing on both sides of the floppy disk, and as a result, the core slit 21 is biased to one side in the lateral direction of the slider 20. It is placed in the raised position. As is well known, when the floppy disk is sandwiched by the magnetic heads from both sides, the recording / reproducing gap or the erasing gap does not face each other on the upper and lower surfaces. Usually, the amount of deviation between the two is set to 8 tracks.

Therefore, in such a slider 20, since the core slit 21 is displaced and arranged on one side in the lateral direction, the side walls 22 and 23 have different wall thicknesses.

When the side walls 22 and 23 having such different thicknesses are formed by integral injection molding of ceramics, a large shrinkage occurs on the side wall 22 side having a large thickness, and the side walls 22 and As a result of the different heights of 23, when the slider 20 is incorporated in the gimbal spring, the sliding contact surface with the recording surface is inclined.

In the present invention, in order to prevent such shrinkage of the thick side wall 22, the large nose 24 is formed on both sides of the nose 24 as shown by reference numerals 32 and 33 in the figure. As a result, the heights of the side walls 22 and 23 can be kept substantially the same during the injection molding process.

On the other hand, on the side wall 23 side, since the wall thickness is thin, injection molding may be performed, and in particular, there is a case where the side wall 23 is collapsed and deformed under the influence of internal stress during cooling or thereafter.
Therefore, in the embodiment, the nose 25 described above,
The back core storage portion 27 connected to this reliably prevents such a fall.

Furthermore, as shown in FIG. 5, the inner surface of the core slit 21 has at least 2 in its longitudinal direction.
And at least one core retainer 34 to 39 is integrally provided in the lateral direction, and the composite magnetic core 10
Can be correctly positioned in the core slit 21. Therefore, when the core 10 is glass-molded into the core slit 21, the core 1 is pressed by the plurality of core retainers 34 to 39.
Since a uniform gap is formed between 0 and the core slit 21, the molten glass can easily flow into this uniform gap, and secure fixation and smooth airtight shield can be performed. In FIG. 6, the slider 20 is combined with the magnetic core 10
Is shown and the back cores 40, 41 are shown at their open ends. The slider 20 is cut at a position approximately in the center in the longitudinal direction. In FIG.
Although the detailed structure of the recording / reproducing coil assembly is omitted, only the terminal group projecting above the gimbal spring 42 when the slider 20 is adhesively fixed to the gimbal spring 42 by its side wall is shown. FIG. 7 is a sectional view of the slider 20 in an assembled state along the longitudinal direction.

As shown in FIGS. 2, 3, 4, 6 and 7, the magnetic head is assembled in the order described in detail later. As is apparent from FIG. 6, in this embodiment, the recording surface of the magnetic disk is The sliding contact surface of the slider 20 which is in sliding contact with the main sliding contact surface 43 which includes the composite magnetic core 10 and performs recording / reproducing and erasing operations, and an auxiliary sliding member which is several tracks away from the main sliding contact surface and is arranged in parallel in the track direction. The contact surface 44 and an escape reference surface 45 which is slightly recessed from the sliding contact surfaces 43, 44. That is, both sliding contact surfaces 43 and 44 have a plateau shape slightly raised from the escape reference surface 45, and as is well known, these sliding contact surfaces 4 are formed.
3 and 44 are opposed to the auxiliary sliding contact surface and the main sliding contact surface of the magnetic head on the opposite side via the floppy disk. In this embodiment, the escape reference surface 45 forms an escape surface that does not contact the recording surface of the floppy disk, and
A reference surface is formed for each part of the slider 20, and a reference position is always provided for the dimensions of each part. As a result, the relief reference surface 45 is provided when the slider 20 is cut, polished, or assembled. The slider 20 is positioned by abutting against a predetermined substrate, and as a result, both sliding contact surfaces 43, 44 are required to have a smoothness on the surface for sliding contact with the recording surface.
Has the advantage of not being damaged during such processing and assembly. In the embodiment, the gap between the sliding contact surfaces 43, 44 and the clearance reference surface 45 is set to 0.05 to 0.35 mm.

In this embodiment, the main sliding contact surface 43 and the auxiliary sliding contact surface 44 are shown in plan view in FIG.
As shown in the figure, both sliding contact surfaces 43 and 44 have symmetrical shapes, but both have an elongated half-moon shape curved outward. Therefore, when the slider 20 actually makes sliding contact on the recording surface of the floppy disk by such a pair of opposed elongated half-moon shapes, the air flow at the sliding contact portion is as shown in FIG. Airflows f ₂ and f ₃ that go around the outsides of both sliding contact surfaces 43 and 44 with respect to the airflow f ₁ that passes through the narrow passage formed by the escape reference surface 45 between the contact surfaces 43 and 44.
Is large and the flow speed is high, and as a result, the slider 20 can stabilize its position. Of course, the slider 20 must move its position by following the recording surface of the floppy disk. In the conventional case, however, the slider itself may vibrate in addition to such a follow-up change, so that the entire surface of the conventional slider cannot be moved. The dynamic slider cannot reliably prevent such vibrations, so it was necessary to improve the gimbal spring and take other vibration prevention measures.
Such measures are not preferable because they generally lead to an increase in size and weight of the device. In the present embodiment, in order to prevent such a conventional defect, the sliding contact surfaces 43 and 44 are made sufficiently smaller than the entire surface of the slider 20 to be the minimum necessary surface, and the main sliding contact surface 43 and By arranging the auxiliary sliding contact surfaces 44 symmetrically to stabilize the two, and by taking an elongated half-moon shape oppositely arranged, vibrations generated in the slider 20 by mechanically utilizing the air flow are prevented. It became possible to prevent it certainly.

Further, in the present invention, in order to easily obtain the above-mentioned shapes of the sliding contact surfaces 43 and 44, the blank itself when injection molding the slider 20 is provided with such a pair of opposed elongated half-moon shapes. There is.

FIGS. 9, 10 and 11 show an example of such a blank in plan, front and side views, respectively.
In the front and side views of FIGS. 10 and 11, the main sliding contact surface 4
3. The plate shape of the auxiliary sliding contact surface 44 is prepared for simultaneous cutting when the composite magnetic core is attached with a sufficient height in advance, but as apparent from the plan view of FIG. It is understood that the blank itself is already almost finished.

Therefore, as shown by the chain lines in FIGS. 10 and 11, after the both sliding contact surfaces 43 and 44 have been ground, the slider 20 is subjected to barrel polishing and brush processing, and the final step as shown in FIG. It is possible to obtain the shape.

Returning to FIG. 8, both sliding contact surfaces 43, 44 have slightly curved planes, and in the figure such curvature is shown by dashed contour lines 43a, 43b and 44a,
It is represented by 44b. Therefore, it is understood from FIG. 8 that the main sliding contact surface 43 has a curved shape with the recording / reproducing and erasing gap of the composite magnetic core 10 as the apex and forming a slightly sloping inclined surface around the gap. The auxiliary sliding contact surface 44 is also provided with a symmetrical shape. In this manner, the slender half-moon shaped sliding contact surfaces 43 and 44 having a slight curvature make sure contact with the recording surface of the floppy disk at the recording / reproducing gap and the erasing gap, and the parallelism between them is small. Even if it shifts to, there is an advantage that recording / reproduction is continued without deteriorating the contact in the gap portion.

In the present invention, the slider 20 is obtained by injection molding as described above, and the injection-molded calcium titanate ceramics-based slider blank is subjected to predetermined grinding and polishing steps and then to the predetermined slider 2.
The composite magnetic core 10 is securely fixed and positioned on the slider 20 with molten glass, and the sliding contact surface is completed.

Returning to FIG. 1, a recording / reproducing coil assembly 50 and an erasing coil assembly 51 are incorporated in the composite magnetic core 10 fixed to the slider 20 described above.
These coil assemblies 50 and 51 have the same bobbin shape, and this bobbin is made of, for example, polyphenylene sulfite (PPS) or polyethylene terephthalate (PE).
T), polybutylene terephthalate (PBT), and the like, made of a plastic in which glass fibers are mixed. The recording / reproducing bobbin 52 is insert-molded with three terminals 53, 54, 55, and the recording coil 5 wound around the bobbin 52.
6, each coil end of the reproducing coil 57 has terminals 53, 54,
It is connected to 55. On the other hand, erase coil bobbin 5
An erasing coil 59 is wound around 8, and both ends of the erasing coil 59 are entwined and connected to two terminals selected from terminals 60, 61 and 62, in the embodiment, terminals 60 and 62. ..

Openings 63 and 64 are provided in the coil cores of both bobbins 52 and 58, and these openings 63 and 64 are provided.
The recording / reproducing side outer core leg 13 and the erasing core side outer core leg 14 of the composite magnetic core 10 are inserted into the respective parts.

On the upper surfaces of both bobbins 52 and 58, rising walls 65, 66 and 6 for accommodating the back cores 40 and 41 are provided.
7, 68 are provided, and these rising walls 65-6
8 are inward projections 65a, 66a, 6 respectively.
7a and 68a are provided, and these projections perform a positioning action when the back cores 40 and 41 are inserted. Further, openings 69, 70, 71, 7 are formed between the protrusions 65a, 66a, 67a, 68a and the upper surfaces of the bobbins 52, 58.
Providing 2 provides a certain degree of elasticity to each of the protrusions, and when the back cores 40 and 41 come into contact with these protrusions, a slight pressing force is applied to the back cores 40 and 41 to ensure their retention. Is effective for.

With such elasticity, the pressing force applied to the back cores 40 and 41 becomes too large, and the composite magnetic core 1 fixed to the slider 20 at the time of assembly.
It is important to prevent a large value that would damage or break 0. As described above, when both coil assemblies 50, 51 are mounted on the composite magnetic core 10 fixed to the slider 20, the back cores 40, 41 are brought into close contact with the open ends of the composite magnetic core 10 in this state. Incorporated. At this time, the coil assembly 5
As described above, the protrusions 65a, 66a, 67a, 68a of 0, 51 are used to determine the temporary positions of the back cores 40, 41.

In the present embodiment, unlike the prior art, the open end of the composite magnetic core 10 is provided with the back cores 40,
41 is fixedly attached, and thus a pair of back cores 4
By using 0 and 41, it is possible to provide a stable back core having a small magnetic resistance. In particular, in the past, most of the conventional structures were such that one back core was forcibly press-fitted between the composite magnetic core and the coil bobbin. Therefore, when inserting the back core between the bobbin and the magnetic core with poor dimensional accuracy, In some cases, the magnetic core may be damaged due to undue stress on the core, and in such a case, the magnetic head assembled with great care must be discarded, which significantly reduces the production yield of the magnetic head. However, according to the present embodiment, the pair of back cores 4
0 and 41 are incorporated into the open end of the composite magnetic core 20 so as to be sandwiched from both sides, and the coil assembly 5 at this time
The back cores 40, 41 are held only temporarily by 0, 51, and both back cores 40, 41 and the composite magnetic core 10 are held.
Since the adhesion resistance to and is surely performed with the silver paste, there is an advantage that a large force as described above that damages the composite magnetic core is not applied, and the μ (permeability) of It also prevents deterioration.

FIG. 4 shows the back cores 40, 4 in this way.
1 is incorporated, and the planar shape at this time is shown in FIG. As is clear from the figure, the pair of back cores according to the present invention, the composite magnetic core 1
By reducing the back magnetic gap between 0 and the back cores 40, 41 to reduce the leakage of magnetic flux and improve the magnetic efficiency, it is possible to provide a magnetic head capable of reliable recording / reproducing with low current consumption.

Further, by improving the magnetic efficiency as described above, it can be sufficiently used for a high density recording magnetic head in recent years, and further, the height of the back cores 40 and 41 can be reduced to make the magnetic head thinner. There is an advantage that you can.

FIG. 13 shows FIG. 12 viewed from the back side.
The state of the silver paste according to the present embodiment when fixing the gimbal spring 42 to the head of No. 3 is shown, and the reference numeral 73 shows the silver paste. As is clear from the figure, this silver paste 73 is combined with both back cores 40 and 41. Each leg 1 of the magnetic core 10
It is applied over the joints with 3, 14, 15, and 16.

Therefore, as described above, the back core 4
It is possible to remarkably reduce the magnetic resistance between the two, without the pressure contact of 0 and 41 with the composite magnetic core as in the conventional case, with the aid of the silver paste 73.

As shown in FIG. 6, after the silver paste 73 is applied, the gimbal spring 42 is fixed to the slider 20 by applying an adhesive around the slider 20, and the silver paste 73 is fixed as shown in the figure. It is pressed by the gimbal spring 42.

Further, according to the present invention, the silver paste 73 is also applied by being connected to the recessed surface 28 provided on the nose 24 on the side wall 22 side, and the gimbal spring 42 and the nose 24 on the thick side wall 22 side. And can be securely fixed.

Therefore, the silver paste 73 first electrically connects the composite magnetic core 10 and the gimbal spring 42 to each other, and as a result, the static electricity applied to the slider 20 can be surely released to the ground side.

Further, as described above, the silver paste 73
Firmly fixes the concave surface 28 connected to the nose 24 of the thick side wall 22 and the gimbal spring 42 integrally, so that vibration, chatter, or squeal phenomenon of the slider 20 that occurs when the slider 20 comes into contact with the floppy disk is effectively suppressed. Therefore, there is an advantage that stable recording and reproduction are possible.

[0053]

As described above, according to the present invention,
By devising the structure of the slider, it is possible to provide a magnetic head that is small and lightweight and has excellent assemblability.

It is possible to improve the magnetic efficiency of the magnetic head to reduce the current consumption or to achieve a high density magnetic head.

Further, according to the present invention, it greatly contributes to reduction in size and thickness of the device. Since the composite magnetic core and the slider body can be firmly fixed and held to the gimbal spring, there is an advantage that the countermeasure against static electricity and the countermeasure against vibration can be achieved with a simple structure.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of essential parts showing a preferred embodiment of a composite magnetic head according to the present invention.

FIG. 2 is an external perspective view of the assembled state of this embodiment when viewed from the front side.

FIG. 3 is a partially transparent perspective view of the assembled state seen from the front side as in FIG.

FIG. 4 is a perspective view when seen from the back side in the assembled state of the present embodiment.

FIG. 5 is a plan view seen from the back side of the slider in the present embodiment.

FIG. 6 is a cross-sectional view of a main part of the composite magnetic head according to the present embodiment, the main part being broken at the center in the longitudinal direction.

FIG. 7 is a cross-sectional view of essential parts of the magnetic head in the assembled state according to the present embodiment.

FIG. 8 is a plan view seen from the front side of the magnetic head in this embodiment.

FIG. 9 is a plan view seen from the front side of the slider blank in this embodiment.

FIG. 10 is a front view of a slider blank according to this embodiment.

FIG. 11 is a side view of the slider blank in this embodiment.

FIG. 12 is a plan view of the assembled magnetic head before the gimbal spring is mounted, as seen from the back side according to the present embodiment.

13 is a plan view showing a state in which the magnetic head of FIG. 12 is coated with a silver paste before being fixed to a gimbal spring.

[Explanation of symbols]

 10 Composite Magnetic Core 11 Recording / Reproducing Core 12 Erase Core 20 Slider 21 Core Slit 22 Thick Wall Side Wall 23 Thin Wall Side Wall 24, 25 Nose 26, 27 Back Core Housing 28, 29 Recessed Surface 30, 31 Short Side End Wall 32 , 33 Meat removing part 40, 41 Back core 42 Gimbal spring 43 Main sliding contact surface 44 Auxiliary sliding contact surface 45 Escape reference surface 50 Recording / reproducing coil assembly 51 Erase coil assembly 52, 58 Bobbin 73 Silver paste

Claims (2)

[Claims] 1. A composite magnetic core consisting of a recording / reproducing core and an erasing core, an integral slider for fixedly supporting the composite magnetic core and in sliding contact with a magnetic recording medium, and a recording through which a core leg of the recording / reproducing core penetrates. A recording / reproducing coil assembly having a reproducing coil and a bobbin holding the recording / reproducing coil, an erasing coil assembly having an erasing coil through which a core leg of the erasing core penetrates, and a bobbin holding the erasing coil, A composite magnetic head comprising: a back core that magnetically closes an open end of the composite magnetic core; and a gimbal spring to which the slider is adhesively fixed, wherein the slider exposes the composite magnetic core to a magnetic recording medium side. A core slit for fixing and a side wall along the longitudinal direction, which has a wide width and a first side wall which is adhesively fixed to the gimbal spring. A second side wall, first and second end walls which are ends along the lateral direction and which are lower in height than the side walls and can accommodate a part of the bobbin on the walls; First nose extending from substantially the center in the core slit direction to prevent the composite magnetic core from collapsing, and a second nose extending from the center of the second side wall to the core slit direction to prevent the composite magnetic core from collapsing. And a back core accommodating portion provided on each of the noses, and a meat removing portion provided on both sides of the first nose of the first side wall for equalizing shrinkage during cooling after injection molding between both side walls. And a composite magnetic head formed by injection molding of ceramics. 2. A composite magnetic head according to claim 1, wherein said slider has a main sliding contact surface provided around said core slit on a sliding contact surface with said magnetic recording medium and symmetrical with this sliding contact surface. And an auxiliary sliding contact surface provided on the sliding contact surface, the sliding contact surfaces being opposed to each other to form an elongated half-moon shape.