JPH0240573Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a floating magnetic head used in magnetic disk drives and the like.

[Background of the idea]

A magnetic head is connected to a magnetic recording medium (magnetic disk, etc.)
Various floating magnetic heads, which are used by floating at a height of about 0.3 to 0.5 μm from the surface of the magnetic head, have been known in the past.

FIG. 3 is an external view showing an example of such a conventional floating magnetic head. In the figure, 1 is the entire floating magnetic head, 2 is a core holder made of a non-magnetic material such as ceramic, 3 is a pair of rails provided on the core holder 2, and 4 is a notch for inserting the magnetic core. 5 is a concave winding groove orthogonal to the notch 4, and 6 is a notch, to which a load applying device (not shown) is attached. Here, the core holder 2 has a surface on which the rail 3 is provided,
That is, the upper surface in FIG. 3 becomes the surface facing the magnetic recording medium. 7 is a magnetic core made of a magnetic material and whose appearance is shown in FIG. 4; 8 is a gap of the magnetic core 7;
D is the gap depth of the gap 8 (hereinafter referred to as gap depth), and the magnetic core 7 is inserted into the notch 4 so that the gap 8 faces the rail 3 side.
After being inserted into the core holder 2, it is fixed to the core holder 2 by glass melting or the like. In order to prevent the magnetic recording medium from being damaged by the magnetic core 7, after the magnetic core 7 is fixed to the core holder 2, the gap surface of the magnetic core 7 and the rail 3 are made to be on the same flat surface. Polished. Reference numeral 9 denotes a coil, and the coil 9 has a winding groove 5 attached to the magnetic core 7 in a portion facing into the winding groove 5.
It is wound using a predetermined number of turns of about 15 to 30.

By the way, the gap depth D of the magnetic core 7 is related to the sensitivity as well as the gap length, and it is said that the shallower the gap depth D, the better the sensitivity tends to be. As described above, the gap depth D has a large effect on the sensitivity of the magnetic head, so when examining the reliability of the magnetic head, it is necessary to accurately measure the gap depth in the finished magnetic head shown in FIG. 3. However, the gear depth is hidden inside the notch 4 in the completed state of the magnetic head, so after inserting the magnetic core 7 into the notch 4 and polishing the gear surface together with the rail 3, it is difficult to remove the gear from the outside. It is difficult to accurately measure the gear depth of the gear. Of course, it is also possible to measure the gear depth D in advance before inserting the magnetic core 7 into the notch 4, and to determine the approximate dimensions of the gear depth in the completed state after polishing from this measured value D. When fixing the core 7 to the core holder 2, the relative positions of the two vary;
Due to such variations, the amount of polishing required to flatten the gap surfaces of the rail 3 and the magnetic core 7 is not constant, so that the obtained gap depth after processing lacks accuracy.

[Purpose of invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a floating magnetic head which eliminates the above-mentioned drawbacks of the prior art and allows the gap depth to be easily measured after the magnetic core is assembled into the core holder.

[Summary of the idea]

To achieve this objective, the present invention forms a reference plane parallel to the gap plane at the bottom of the winding window of the magnetic core, and exposes the reference plane in the winding groove of the core holder. It is characterized by a magnetic core fixed to the notch.

[Example of idea]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of the floating magnetic head according to the present invention, FIG. 2 is a side view of the magnetic core before being inserted into the floating magnetic head shown in FIG. 1, and FIG.
Portions corresponding to those in FIG. 4 are given the same reference numerals.

The magnetic core 7 shown in FIG. 2 has basically the same structure as the conventional magnetic core described above (see FIG. 4), but the bottom part of the winding window 10, that is, the part parallel to the gap surface. is defined as reference plane A. In the magnetic core 7, the dimension _l1 between the reference plane A and the bottom of the gear depth D is measured in advance.

The magnetic core 7 is inserted into the notch 4 of the core holder 2 and fixed by glass welding or the like, as in the conventional example described above, but at this time, as shown in FIG. is made to protrude from the bottom of the winding groove 5. Thereafter, the rail 3 of the core holder 2 and the gap surface of the magnetic core 7 are polished so that both become flat surfaces, and the magnetic core 7 is polished using the winding groove 5.
A coil (not shown) is wound around the magnetic head, and the completed magnetic head is assembled. In addition, as shown in Figure 1
D ₁ indicates the gear depth in the finished product of the magnetic head;
Due to the polishing process, _D1 becomes somewhat shorter than the gear depth D before assembly (see Figure 2), so it is no longer possible to directly measure the gear depth _D1 from the outside. Therefore, we measured the dimension l ₂ from the reference plane A of the magnetic core 7 visible through the winding groove 5 to the rail 3 after polishing (this is the same plane as the gap surface), and measured from this l ₂ first. Subtract l ₁ and find the gear depth D ₁ as D ₁ = l ₂ - l ₁ .

Gear depth calculated in this way
The dimension of D ₁ is extremely accurate since both l ₁ and l ₂ are measurable values, and therefore the dimensional accuracy of the gap depth in the magnetic head can be improved.

[Effect of idea]

As explained above, according to the present invention, even in the completed state of the magnetic head in which the magnetic core is assembled into the core holder and the gap surface is polished, the dimension of the gap depth can be calculated by calculating the actually measurable measurement value. It is possible to accurately determine the gap depth, thereby increasing the dimensional accuracy of the gear depth and improving the reliability of the magnetic head.

[Brief explanation of the drawing]

Fig. 1 is a side view of the floating magnetic head according to the present invention, Fig. 2 is a side view of the magnetic core before being inserted into the floating magnetic head shown in Fig. 1, and Fig. 3 is a side view of a conventional floating magnetic head. 4 is an external view of the magnetic core before it is inserted into the floating magnetic head shown in FIG. 3. FIG. 2... Core holder, 3... Rail, 4... Notch, 5... Winding groove, 7... Magnetic core, 8... Gap, 9... Coil, 10... Window, A... Reference Surface, D, D ₁ ...Gear depth.

Claims (1)

[Scope of utility model registration request] A core holder is provided with a notch and a winding groove that crosses the notch, a magnetic core having a winding window and a gap is inserted into the notch, and the magnetic core faces into the winding groove of the magnetic core. In a floating magnetic head in which a coil is wound around the window, a reference plane parallel to the gap plane is formed at the bottom of the window of the magnetic core, and the magnetic head is arranged such that the reference plane is exposed in the winding groove. A floating magnetic head characterized in that a core is fixed to the notch.