JPH06274820A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To produce the magnetic head having high dimensional accuracy at a good yield by continuously forming recording and reproducing tracks and erasing tracks on the same magnetic core substrate while changing feed pitches alternately by using the same cutting machine. CONSTITUTION:A winding groove 3 for insertion of a bobbin (not shown in Fig.) to be wound with windings when the head is completed and a glass groove 4 are formed on the main surface of one substrate 1 of a pair of the ferrite substrates 1, 2 over the entire part of the substrate in the longitudinal direction thereof. This winding groove 3 is formed by forming a slope 3a for regulating gap depth on the butt surface of the substrate 1 and a bobbin mounting surface 3b in parallel with the butt surface from the rear end edge thereof. On the other hand, the glass groove 4 is formed as a groove having nearly a 'U'-shape in section on the lower side of the winding groove 3 so as to be parallel with this groove 3. The substrates 1, 2 are set on the same cutting machine and the recording and reproducing tracks TW1 and the erasing tracks TW2, TW3 are continuously and simultaneously formed on the substrates 1, 2 by the same grindstone while the feed pitches are changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magnetic head suitable for writing and / or reproducing information signals on, for example, a floppy disk.

[0002]

2. Description of the Related Art For example, a floppy head for writing and / or reproducing information signals on a floppy disk is manufactured through the following steps. First, as shown in FIG. 7, a plurality of recording / reproducing tracks Tw ₁ for recording / reproducing are formed at a predetermined pitch on the main surfaces of the pair of ferrite substrates 101, 102.

Recording / reproducing track Tw₁In forming
As shown in FIG. 8, the grindstone width W ₁(Record / playback track
(Corresponding to the groove formation regulation groove 112) is set to 151 μm
Pitch P₁Is set to 282 μm and the recording / reproducing track is set.
Ku Tw₁Is adjusted by a cutting machine so that
Work. After that, each of these ferrite substrates 101, 1
The recording / reproducing track Tw formed in 02.₁Align
While abutting and gap joining.

Next, as shown in FIG. 7, a plurality of erasing tracks Tw ₂ and Tw ₃ for erasing are formed on the main surfaces of the pair of ferrite substrates 103 and 104 at a predetermined pitch. When forming the erase tracks Tw ₂ and Tw ₃ , as shown in FIG. 9, the grindstone width W ₂ (the erase track formation restricting groove 11
(Corresponding to 3) is 125 μm, and the feed pitch P ₂ is 1
Setting to 88 μm, erase tracks Tw ₂ and Tw ₃ are 6
It is processed by a cutting machine so as to have a thickness of 3 μm.

After that, each of the ferrite substrates 10
The erase tracks Tw ₂ and Tw ₃ formed on the surfaces ₃ and 104 are abutted with each other while aligning them to form a gap junction.

Next, the gap-bonded block 10 is formed.
Winding grooves 107, 10 for winding the coiled bobbin (not shown) on the side where 5, 106 are combined.
Ferrite substrate 101, 10 on the side where 8 is not formed
4 is thinned so that it has a predetermined size as shown in FIG. Next, these blocks 105 and 106
The recording / reproducing track Tw ₁ and the erasing track Tw ₂ ,
In a state where the relative positions of Tw ₃ are aligned so as to have a predetermined relationship, as shown in FIG.
It is joined and integrated by 09.

And finally, this united block 1
05 and 106 are cut at predetermined positions as shown in FIG. As a result, the recording / reproducing head 110 and the erasing head 1
A floppy head in which 11 is integrated is obtained.

[0008]

In a floppy head in which the recording / reproducing head 110 and the erasing head 111 are integrated, the relative positional relationship between the recording / reproducing track Tw ₁ and the erasing tracks Tw ₂ , Tw ₃ is the recording / reproducing characteristic. Of the recording / reproducing track Tw.
The relative positions of ₁ and the erase tracks Tw ₂ and Tw ₃ are extremely important.

However, as described above, the recording / reproducing head is
In the recording 110 and the erasing head 111, the recording / reproducing track T
w₁And erase track Tw₂, Tw₃Whetstone when forming
Width W ₁, W₂Due to the different cutting machines
Must be grooved. Therefore, each cutting machine
Accuracy, grinding fluid temperature, room temperature changes, etc.
It affects the grooving accuracy of the cutting machine,
Cook Tw₁And erase track Tw₂, Tw₃In place
Track deviation occurs when adjusting the position and size. This
As a result, the preset recording / reproducing track Tw₁And erase
Truck Tw₂, Tw₃The relative position of the
The track position is different for each card, and the manufacturing yield is remarkable.
descend.

Therefore, the present invention has been proposed in order to solve such a conventional problem, and an object of the present invention is to manufacture a highly accurate magnetic head in which there is no positional deviation between a recording / reproducing track and an erasing track with a good yield. .

[0011]

In order to achieve the above-mentioned object, the present invention provides a method of manufacturing a magnetic head in which a recording / reproducing head and an erasing head are integrated, and at least a pair of magnetic core substrates are provided with a main surface. Recording and reproducing tracks and erasing tracks are continuously and alternately formed by changing the feed pitch by the same grindstone, and the grooved magnetic core substrate is gap-bonded so that the recording and reproducing tracks and the erasing tracks are aligned. After creating the head block,
It is characterized in that these head blocks are joined and integrated so that a recording / reproducing track and an erasing track formed in each head block face each other and are cut into chips.

Further, in this manufacturing method, the magnetic head is a floppy head for writing and / or reproducing an information signal on a floppy disk.

[0013]

In the method of the present invention, the same cutting machine is used, the width of the grindstone is the same, the recording / reproducing track and the erasing track are alternated, and the feed pitch is continuously changed to the same magnetic core substrate. Since they are formed, the relative positions of the recording / reproducing track and the erasing track when the head blocks are united can be made highly accurate without affecting the feed error of the cutting machine, the temperature of the grinding fluid, the room temperature, or the like. Therefore, a magnetic head with high dimensional accuracy can be manufactured with high yield.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described below with reference to the drawings. This embodiment is an example applied to a floppy head for writing information signals to a floppy disk, reading information signals recorded on a floppy disk, or both.

In order to manufacture the floppy head of this embodiment, first, as shown in FIG. 1, a pair of ferrite substrates 1,
Prepare 2. Next, a winding groove 3 for inserting a bobbin (not shown) formed by winding a winding when the head is completed, on the main surface of one ferrite substrate 1,
The glass groove 4 is formed in the longitudinal direction over the entire substrate.

The winding groove 3 has an inclined surface 3a for restricting the gap depth on the abutting surface of the ferrite substrate 1, and a bobbin mounting surface 3b parallel to the abutting surface from the rear edge thereof.
It is created by forming and. On the other hand, the glass groove 4
Is formed below the winding groove 3 so as to be parallel to the winding groove 3 as a groove having a substantially U-shaped cross section.

Next, the ferrite substrates 1 and 2 are the same.
Set on the cutting machine. And these ferrites
Feed pitch for substrates 1 and 2 simultaneously with the same grindstone
Recording / playback track Tw while changing₁And erase
Rack Tw₂, Tw ₃To form. That is, as shown in FIG.
First, the feed pitch P₁Is set to 256 μm,
Groove width W with the same grindstone₁To 125 μm
By inserting the cutting groove 5 having a substantially V-shaped surface,
Recording / reproducing track Tw with a width of 131 μm₁To form.
In addition, the cutting groove 5 is directly connected to the winding groove 3 and the glass groove 4.
Form in the intersecting direction.

Then, the feed pitch P ₂ is changed to 188 μm, the cutting groove 5 having a substantially V-shaped cross section is formed by the same grindstone, and the erase track Tw having a track width of 63 μm is formed.
Form ₂ . Subsequently, an erase track Tw ₃ having a track width of 63 μm is formed with the same feed pitch P ₂ . Hereinafter, by repeating the feed pitch P ₁ of 256 μm and the feed pitch P _{2 of} 188 μm twice, the recording / reproducing track Tw ₁ and the two erasing tracks Tw ₂ , T 2 are repeated.
The formation of w ₃ is sequentially repeated.

For grooving, an NC (numerical control) cutting machine capable of continuously varying the feed pitch is used. According to such an NC cutting machine, the feed pitch can be appropriately changed with high accuracy without stopping the machine, and continuous cutting can be performed.

Next, the ferrite substrate 1 having the winding groove 3 formed therein and the ferrite substrate 2 having no winding groove 3 formed therein are butted and joined together as shown in FIG.
At this time, the recording / reproducing track Tw ₁ and the erasing tracks Tw ₂ and Tw ₃ formed on the ferrite substrates 1 and 2 are formed alternately by the same cutting machine with the same grindstone while changing the feed pitch. Tracks can be easily aligned by simply aligning the end faces of the ferrite substrates 1 and 2 without affecting the cumulative feed error of the machine, and as shown in FIG. 4, there is no displacement of each track. . Even if the grinding liquid temperature or the room temperature changes, the ferrite substrates 1 and 2 are simultaneously grooved by the same cutting machine, and therefore the track positions of the recording / reproducing tracks Tw ₁ formed at the opposite positions. Match.

Next, in the gap-bonded head block 6, when the recording / reproducing track portion and the erasing track portion are combined, the ferrite substrate 2 on the combined side is polished to a predetermined size. make it thin. Then, the same head block (not shown) as the head block 6 formed through the above-described steps is formed on the recording / reproducing track Tw ₁ formed on one head block 6 and the other head block. Erase track T
It is arranged in a predetermined positional relationship so that w ₂ and Tw ₃ face each other.

Then, in this state, the head blocks 6 are joined and integrated by a joining member 7 made of glass or the like.

Next, the head block 6 joined and integrated by the joining member 7 is cut into chips, as shown in FIG.
A magnetic head in which the recording / reproducing head 8 and the erasing head 9 shown in FIG. The floppy head shown in FIG. 6 is completed by integrating the pair of guard members 10 and 11 with this.

[0024]

As is clear from the above description, according to the method of the present invention, the same cutting machine is used, the width of the grindstone is made the same, and the recording / reproducing track and the erasing track are alternately fed. Since it is formed continuously on the same magnetic core substrate while changing the pitch, it does not affect the cumulative error of the cutting machine, the temperature of the grinding fluid, the room temperature, etc. The position is highly accurate, and a magnetic head with high dimensional accuracy can be manufactured with high yield. Also, since the same grindstone is used, the width of grindstone differs from the conventional one.
It eliminates the need to create different types of grindstones and improves machine efficiency.

[Brief description of drawings]

FIG. 1 is a perspective view sequentially showing a process of manufacturing a floppy head to which the present invention is applied, showing a process of grooving a ferrite substrate.

FIG. 2 is an enlarged plan view of an essential part of one ferrite substrate shown in FIG. 1, showing the manufacturing steps of a floppy head to which the present invention is applied in sequence.

FIG. 3 is a perspective view showing a gap joining step, which sequentially shows the steps of manufacturing a floppy head to which the present invention is applied.

FIG. 4 is a magnified plan view of an essential part of the head block shown in FIG. 3, showing the manufacturing steps of the floppy head to which the present invention is applied in sequence.

FIG. 5 is a perspective view sequentially showing a process of manufacturing a floppy head to which the present invention is applied, showing a process of joining a guard member to an integrated recording / reproducing head and erasing head.

FIG. 6 is a perspective view sequentially showing a process of manufacturing a floppy head to which the present invention is applied, showing a state in which a guard member is joined to an integrated recording / reproducing head and erasing head.

FIG. 7 is a perspective view showing a step of manufacturing a floppy head by a conventional method in sequence and showing a gap bonding step.

FIG. 8 is an enlarged plan view of an essential part of a ferrite substrate in which only a recording / reproducing track is formed in one block, which sequentially shows steps of manufacturing a floppy head by a conventional method.

FIG. 9 is an enlarged plan view of an essential part of a ferrite substrate in which only erase tracks are formed in the other block, which sequentially shows steps of manufacturing a floppy head by a conventional method.

FIG. 10 is a perspective view showing a step of joining blocks, sequentially showing steps of manufacturing a floppy head by a conventional method.

FIG. 11 is a perspective view showing a chip cutting step, which sequentially shows steps of manufacturing a floppy head by a conventional method.

[Explanation of symbols]

1, 2 ... Ferrite substrate 3 ... Winding groove 4 ... Glass groove 5 ... Cutting groove 6 ... Head block 8 ... Recording / reproducing head 9 ... Erase head 10, 11 ... ..Guard members Tw ₁ ... Recording / reproducing tracks Tw ₂ , Tw ₃ ... Erase tracks

Claims (2)

[Claims] 1. A method of manufacturing a magnetic head in which a recording / reproducing head and an erasing head are integrated, wherein a recording / reproducing track and an erasing track are continuously formed on at least a pair of main surfaces of a magnetic core substrate while changing the feed pitch with the same grindstone. Are alternately formed, and the grooved magnetic core substrate is gap-bonded so that the recording / reproducing tracks and the erasing tracks are aligned with each other to form a head block. A method of manufacturing a magnetic head, characterized in that the formed recording / reproducing track and the erasing track are joined and integrated so as to face each other and the chip is cut. 2. The method of manufacturing a magnetic head according to claim 1, wherein the magnetic head is a floppy head for writing and / or reproducing information signals on a floppy disk.