JPH0538407Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Field of Application] The present invention relates to a floating magnetic head, and more particularly to a floating magnetic head that has an excellent flatness on the air bearing surface. [Prior Art] A floating magnetic head, which is floated by an air flow on the disk surface as the magnetic disk rotates, has been known as a magnetic head for magnetic recording in magnetic disk devices. An example of a conventional floating magnetic head is shown in FIG. The floating magnetic head 1' basically consists of a slider 2' made of ceramic or the like and a magnetic core 3'. Two rails 4' and 5' extending in the longitudinal direction are provided parallel to each other on the surface of the slider 2' facing the magnetic disk. A flat part 6a' and a tapered part 6b' are formed on the surfaces of the rails 4' and 5', and this surface is used as an air bearing surface (hereinafter referred to as an ABS surface) for floating by the airflow generated by the rotation of the magnetic disk. ). Further, the slider 2' is provided with various slots.
That is, a bleed slot 7' for air flow is provided on the surface of the slider 2' facing the magnetic disk, and a large suspension slot 8' is provided on the bottom surface of the slider 2' for attaching a spring load adding device such as a gimbal. A coil widening slot 9' for winding and a core slot 11' for setting a magnetic core 3' are provided on the side surface. On the other hand, the magnetic core 3' is made of a material such as ferrite, and the magnetic gap 1 is formed by joining a pair of bars.
2' is formed. The magnetic core 3' is fixed in the core slot 11' so that the magnetic gap 12' is exposed to the ABS surface. Also,
A coil is wound around the fixed magnetic core 3' using a coil widening slot 9'. Incidentally, in recent years, with the miniaturization and high-density recording of magnetic disk devices, the miniaturization of magnetic heads has progressed, and in particular there has been a strong demand for reducing the flying height of magnetic heads. Therefore, it has become necessary to finish the flatness of the ABS surface of the magnetic head with greater precision and accuracy. [Problems to be solved by the invention] However, since the conventional floating magnetic head shown in FIG. 3 is provided with a plurality of slots as described above, the strength of the slider 2' becomes unstable.
During the final flattening (lap processing) of the ABS surface,
There is a problem that deflection tends to occur and the accuracy of the flatness of the ABS surface is poor. In particular, the thickness between the coil widening slot 9' and the ABS surface is thin.
Moreover, since the strength of the part where the core 3' is set is different from the strength of the other parts, the current situation is that the variation in flatness is particularly large. Further, as the slider itself becomes smaller, the coil widening slot 9' also becomes narrower, so winding the coil takes more time and the number of windings is limited, which limits performance. Furthermore, it takes time to set the magnetic core 3',
There were problems such as low productivity. This invention was developed in view of the above-mentioned problems, and its purpose is to eliminate the deflection of the ABS surface.
To provide a floating magnetic head with improved flatness, easy winding of a coil, excellent bonding strength between the magnetic core itself and the magnetic core and a slider, and excellent manufacturing efficiency. [Means for Solving the Problem] According to the present invention, a plurality of rails having an air bearing surface facing a magnetic recording medium, and a rear end portion of one of the rails in the longitudinal direction, facing each other. A slider comprising a core slot consisting of an inner facing surface and an outer facing surface that match, a magnetic core embedded in the core slot with a magnetic gap exposed on the rail surface, and a coil wound around the magnetic core. In the floating magnetic head, a stepped portion is provided on the side bottom side of the slider so that a part of the inner facing surface of the core slot is exposed, and one main portion of a substantially U-shaped front core having a magnetic gap is provided. The front core is joined to the inner facing surface of the core slot, and a part of the other main surface is joined to the outer facing surface of the core slot, and furthermore, a substantially U-shaped coil is wound around the lower half of the other main surface of the front core. This is a floating magnetic head with a back core joined to one main surface. [Function] As described above, by minimizing the number of slots formed in the slider, it is possible to eliminate the deflection of the slider during lapping processing and improve the flatness of the ABS surface. Also,
A small slider is possible. Furthermore, since one main surface of the back core is surface-bonded to the lower half of the other main surface of the front core constituting the magnetic core, the bonding area can be increased and the bonding strength can be improved. Furthermore, since the coil winding can be applied to the back core before being joined to the front core, space can be provided and manufacturing efficiency can be increased. [Example] Hereinafter, the present invention will be explained in detail with reference to FIGS. 1 and 2. FIG. 1 is an exploded perspective view showing an embodiment of the floating magnetic head of the present invention. In the figure, 1 is a floating magnetic head, 2 is a slider, and 3 is a magnetic core. The slider 2 is provided with two rails 4 and 5 on a surface facing a magnetic recording medium such as a magnetic disk, and a bleed slot 6 is formed between the rails 4 and 5. A core slot 7 having two opposing surfaces 7a and 7b for installing the magnetic core 3 is provided at the rear end of the slot of one of the rails 5. Here, the inner opposing surface of the slider 2 is referred to as an inner opposing surface 7a, and the outer opposing surface of the slider 2 is referred to as an outer opposing surface 7b. The characteristics of slider 2 in this invention are essentially
Various slots that cause deflection during flattening of ABS surfaces are omitted as much as possible. That is, in FIG. 1, the large suspension slot 8' and coil widening slot 9 in the prior art shown in FIG. 3 are omitted. With this configuration, it is possible to improve the strength of the slider 2,
Can prevent deflection when flattening ABS surfaces. According to the present invention, the coil 1 connected to the magnetic core 3
The winding of 0 is performed at the bottom of the slider 2. However, in the present invention, the bottom surface of the side surface of the slider 2 has a depth that reaches the core slot 7 (the outer facing surface 7 constituting the core slot 7).
A step portion 8 (corresponding to the thickness of the slider 2 and the side surface of the slider 2) is provided parallel to the rail of the ABS surface of the slider 2, and a cavity space A is formed. That is, a part of the inner facing surface 7a of the core slot 7 (hereinafter referred to as the extending surface 7c of the inner facing surface) is exposed from this cavity space A. On the other hand, the magnetic core 3 is composed of a roughly U-shaped front core 3a and a roughly U-shaped back 3b, and the front 3a has a magnetic gap 9 formed by joining a pair of bars made of magnetic material. Further, the length l ₁ of the front core 3a is set to be approximately the same as the thickness L of the slider 2. The leg of the bug core 3b is the front core 3.
A ring-shaped magnetic circuit is formed as a whole by joining it to the lower half of the leg of a. The structure and method for attaching the magnetic core 3 to the slider 2 will be explained based on FIG. 2. First, the front core 3a is inserted into the core slot 7 and fixed by adhesive using a desired adhesive means. This adhesion is performed by pouring an adhesive such as glass into the gap between the two opposing surfaces 7a and 7b constituting the core slot 7 of the slider 2 and the front core 3a. As a result, the front core 3
a is joined between the inner facing surface 7a, the outer facing surface 7b, and the extending surface 7c of the inner facing surface exposed to the cavity space A, which sandwich it.
That is, the front core 3a is substantially in front of one main surface of the front core 3a (the surface that joins with the inner facing surface 7a of the core slot 7 and its extension surface 7c) and the other main surface of the front core 3a (the outer facing surface of the core slot 7). A part of the surface (which is joined to the surface 7b) will be joined to the slider 2. Next, when the front core 3a is fixed, the surfaces of the rails 4 and 5 are lap-polished to flatten the ABS surfaces. Thereafter, the back core 3b, on which the coil 10 has been wound in advance, is connected to the slider 2.
The legs of one main surface of the back core 3b are offset and superimposed on the lower half of the legs of the other main surface of the front core 3a, which protrudes from the bottom surface of the front core 3a and is exposed to the cavity space A, and are adhesively fixed thereto. This forms a ring-shaped magnetic closed circuit. Both cores 3 are bonded using adhesive such as epoxy resin.
It is connected to the legs of a and 3b or the inner wall of cavity space A. With this configuration, the front core 3a is held and fixed between the inner facing surface 7a exposed from the cavity space A and the legs of the back core 3b, which contributes to miniaturization and high-density recording of the magnetic head. Accordingly, even if the front core 3a becomes thinner, it can be held firmly and stably. Moreover, by using the U-shaped back core 3b instead of the coil widening slot in the conventional technology, it is possible to freely adjust the winding space by changing the overlapping area of the legs of the front core 3a and the back core 3b. Therefore, even when the number of windings increases as the output of the magnetic head increases, it can be adequately coped with. Furthermore, by performing the coil winding process as a separate process, it can be easily performed and damage to the magnetic core during winding of the coil can be prevented as in the conventional method. Next, the flatness workability of the floating magnetic head of the present invention and the conventional floating magnetic head was investigated.
Calcium titanate is used as the slider material and Mn-Zn ferrite is used as the core material, and each core is glass-attached to the conventional magnetic head shown in Fig. 3 and the magnetic head of the present invention shown in Fig. 1. We performed lap processing on the ABS surface. 100 samples were manufactured with flatness of 5μ, 4μ, and 3μ as standards, and the pass rate was determined. The results are shown in Table 1.

[Effect of idea]

As described in detail above, the floating magnetic head of the present invention forms a cavity space by providing a stepped portion at the bottom of the side surface of the slider that reaches the core slot, and separates the magnetic core from the front core and the back core. By connecting these two in the cavity space, the slider
Since it is possible to prevent the slider from deflecting when flattening the ABS surface, the accuracy of flatness can be improved. Furthermore, since the coil is wound at the bottom of the slider, any restrictions on the winding space are eliminated, making it possible to accommodate various arrangements. Furthermore, alignment when the magnetic core is attached becomes easier, and the strength of the core itself, the strength of its connection with the slider, and mechanical stability can also be achieved.

[Brief explanation of the drawing]

The first is an exploded perspective view showing an embodiment of the floating magnetic head of the present invention, the second is an external view of the floating magnetic head of the present invention as seen from the rear end side, and the third is a conventional floating magnetic head. FIG. 3 is a perspective view of a magnetic head. 1...Floating magnetic head, 2...Slider,
3...Magnetic core, 3a...Front core, 3b...
...Back core, 4, 5...Rail, 7...Core slot, 7a...Inner facing surface, 7b...Outer facing surface, 8...Step, 9...Magnetic gap, 10...
coil.

Claims (1)

[Claims for Utility Model Registration] A plurality of rails having air bearing surfaces facing the magnetic recording medium, and an inner facing surface and an outer facing surface facing each other at the rear end in the longitudinal direction of one of the rails. A floating magnetic head comprising: a slider having a core slot consisting of a surface; a magnetic core embedded in the core slot with a magnetic gap exposed on the rail surface; and a coil wound around the magnetic core. , a step is provided on the side bottom surface of the slider so that a part of the inner facing surface of the core slot is exposed, and one main surface of a substantially U-shaped front core having a magnetic gap is connected to the inner facing surface of the core slot. Then, a part of the other main surface is joined to the outer facing surface of the core slot, respectively, and one main surface of a substantially U-shaped back core having a coil wound thereon is joined to the lower half of the other main surface of the front core. A floating magnetic head characterized by: