JPH08203011A - Method for manufacturing magnetic head device - Google Patents

Abstract

PURPOSE: To manufacture a magnetic head device capable of performing excellent recording/reproducing without causing any shifts in the curved surface center of the magnetic recording medium sliding surface of a head chip. CONSTITUTION: A magnetic core block 21 provided with each groove section 33 is set in a specified jig 44 and a supporting block 41 is disposed in both of its side sections. Then, by using a disk-like grinding wheel 42 narrower than a grinding wheel 32, grinding is performed narrower from a grinding surface (a) side to the groove section 33 making it correspond to each groove 33.

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 device mounted on, for example, a VTR (video tape recorder).

[0002]

2. Description of the Related Art Generally, in a rotary type magnetic head device mounted on a VTR, as shown in FIG. 10, for example, a head chip 101 having a predetermined magnetic gap g is adhesively fixed to a head substrate made of brass or the like. Is configured. Here, in the head chip 101, a gap film which is an electrical shielding film made of, for example, SiO ₂ or glass is formed on each abutting surface of a pair of magnetic cores 111 and 112 made of a magnetic material such as ferrite. The abutting surfaces are abutted with each other to form a closed magnetic path, and the fused glass 114 is used for adhesion. At this time, a magnetic gap g is formed on the magnetic recording medium sliding surface a of the head chip 101. A winding groove is formed in the magnetic core 112, and a winding window 113 is formed in abutment with the magnetic core 111. A conductor wire is wound around the winding window 113 to form a coil (not shown).

In order to manufacture the above magnetic head device, first, a pair of magnetic core block halves are butted against each other via the gap film and bonded and integrated with a fused glass 114 to form a magnetic core block 121 having a plurality of magnetic gaps. Create. Next, after performing a cylindrical grinding on the polishing surface a ′ which is the sliding surface a of the magnetic recording medium of the magnetic core block 121 by using a cylindrical grinder, as shown in FIG. The support blocks 122 are arranged on both sides of the tool 123, and the disk-shaped grindstone 124 is used to grind from the polishing surface a side along the broken line S4 in the direction of the arrow K along each magnetic gap g. Give.

Thereafter, the ground portion of the magnetic core block 121 is packed with resin or the like to prevent dispersion, and
As shown in FIG. 3, each head chip 101 is cut into a predetermined chip width by cutting the bottom of the groove 125 formed in a comb shape by the above polishing along the broken line S5. The winding window 11 of the head chip 101
After performing post-processing such as winding on the magnetic head 3, the head chip 101 is placed on the head substrate and adhesively fixed to complete the magnetic head device. The magnetic head devices are mounted, for example, in sets of two on a predetermined rotating drum.

[0005]

By the way, when manufacturing the above magnetic head device, the quality of the positional accuracy of the magnetic gap g in the head chip 101 is an extremely important factor that influences the characteristics of the recording / reproducing signal. Therefore, not only the processing accuracy of the magnetic gap g but also the accuracy when assembling the magnetic head device is essential for improving the recording / reproducing signal characteristics.

However, when the magnetic head device is manufactured by the above-mentioned method, when cutting out each head chip 125 from the magnetic core block 121, due to abrasion or bending of the disk-shaped grindstone 124, as shown in FIG. The back side of each cut out head chip 101 (head chip 1
01 is larger than the chip width on the magnetic recording medium sliding surface a side, that is, as shown in FIG. 14, the head chip 101 has a lateral shape on the sliding surface a side. Therefore, it will be wedge-shaped from the back side.
At this time, the head chip 101 is attached to the head substrate 102.
When the head chip 101 is mounted on the
1a is not parallel to the attachment surface 102a of the head substrate 102, and is inclined by an angle indicated by L1 and L2 in the figure. Therefore, the center of the curved surface of the sliding surface a of the head chip 101 is displaced, and the expected recording / reproducing signal characteristics cannot be obtained.

The present invention has been made in view of the above problems, and an object of the present invention is to achieve extremely good recording / reproducing without causing a deviation in the center of the curved surface of the magnetic recording medium sliding surface of the head chip. It is an object of the present invention to provide a method of manufacturing a magnetic head device capable of performing the above.

[0008]

The object of the present invention is a method of manufacturing a magnetic head device which is constructed by providing a head chip on a head substrate. In the present invention, with respect to a magnetic core block having a plurality of magnetic gaps formed on a polishing surface serving as a sliding surface of a magnetic recording medium, each groove portion from a back side to a midway portion of the magnetic core block at a cutting position of a head chip. And a step of grinding each head chip by grinding until it reaches the groove portion from the polishing surface side with a grindstone narrower than the groove portion corresponding to each groove portion, and installing the head chip on the head substrate The magnetic head device as described above is manufactured by performing the steps described above. Here, the back side is the side opposite to the polishing surface (magnetic recording medium sliding surface).

At this time, when the magnetic head device is viewed from the side surface thereof, the length of the portion of the cut face of the head chip facing the head substrate, which is defined by the groove formed by the grindstone, is defined as the facing face. It is desirable to fabricate the head chip so that the length is less than half the length. By manufacturing in this way, the head chip and the head substrate are arranged in parallel more accurately and surely.

[0010]

In the present invention, after forming each groove portion from the back side to the midway portion of the magnetic core block at the cutting position of the head chip with respect to the magnetic core block, the width is narrower than the groove portion corresponding to each groove portion. Each head chip is cut out by grinding with the grindstone from the polishing surface side until reaching the groove. At this time, in the manufactured head chip, the chip width on the magnetic recording medium sliding surface side is constant, and the back side chip width is smaller than the magnetic recording medium sliding surface side chip width. It will be.

Therefore, when the head chip is adhered and fixed to the head substrate, the surface of the head chip facing the head substrate is parallel to the head substrate in the vicinity of the sliding surface of the magnetic recording medium. The head chip is installed without any inclination between the head chip and the head substrate, and the center of the curved surface of the sliding surface of the magnetic recording medium slides with the magnetic recording medium during recording and reproduction. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method of manufacturing a magnetic head device according to the present invention will be described below with reference to the drawings. The magnetic head device manufactured according to the present embodiment is a rotary type that is mainly mounted on a VTR, and as shown in FIG. 1, a head substrate 1 in which a head chip 1 having a predetermined magnetic gap g is made of brass or the like. It is configured to be adhesively fixed to 2.

In the head chip 1, a pair of magnetic cores 11 and 12 made of a magnetic material such as ferrite is provided with a gap film, which is an electrical shielding film made of, for example, SiO ₂ or glass, on each of the abutting surfaces. The abutting surfaces are abutted with each other to form a closed magnetic circuit, and the fused glass 14 is used for adhesion. At this time, a magnetic gap g is formed on the magnetic recording medium sliding surface a of the head chip 1. A winding groove is formed in the magnetic core 12, and a winding window 13 is formed in abutment with the magnetic core 11. A conductor wire is wound around the winding window 13 to form a coil (not shown).

Here, in the head chip 1, the chip width t1 on the magnetic recording medium sliding surface a side is constant, and the back side chip width t2 indicated by the arrow 15 is on the magnetic recording medium sliding surface. It is smaller than the chip width t1 on the a side. At this time, when the magnetic head device is viewed from the side, the length of the portion of the facing surface of the head chip 1 with respect to the head substrate 2 defined by the groove 33 formed by the grindstone 32 is the length of the facing surface. It is fixedly adhered to the head substrate 2 with an instant adhesive 16 or the like so as to be less than half the length. At this time, the adhesive fixing portion may be reinforced with an ultraviolet curable adhesive or the like.

As shown in FIG. 3, the magnetic head device having the above-described structure is mounted on the rotary drum 3 at a connecting portion 17 formed on each head substrate 2 in pairs, for example. It To manufacture the above magnetic head device,
First, as shown in FIG.
The pair of magnetic core block halves 22 and 23, which have been cut, are butted against each other via the gap film 24, and as shown in FIG. At this time, a plurality of magnetic gaps g having a predetermined gap length are formed at equal intervals.

Next, the arrow 1 of the magnetic core block 21.
A jig (not shown) with the back side indicated by 5 as the upper side
As shown in FIG. 6, a disk-shaped grindstone 32 is used along the broken line S1 in the direction indicated by the arrow M at the cutting position of the head chip 1 with respect to the magnetic core block 21 for each magnetic gap g. Then, each groove 33 having a groove width d1 is formed by grinding the back side to a predetermined depth D. Here, as the grindstone 32, a grindstone having a predetermined width larger than that of the grindstone 42 described later is used.

After that, a cylindrical grinding machine is used to cylindrically grind a polishing surface a'of the magnetic core block 21 which is a sliding surface a of the magnetic recording medium, and then, as shown in FIG. It is installed on a predetermined jig 44 and support blocks 41 are arranged on both sides thereof, and a disc-shaped grindstone 42 narrower than the grindstone 32 is used to correspond to each groove 33 and narrower than the groove 33. To the groove width d2 from the polishing surface a side
Grind until it reaches.

Next, as shown in FIG. 8, the separating portions of the magnetic core block 21 are packed with resin or the like 52 to prevent dispersion, and the bottom portion of the groove portion 33 formed in a comb shape by the above polishing is indicated by an arrow N. By cutting along the broken line S2 in the direction shown by, each head chip 1 having a chip width t1 near the sliding surface a and a back side chip width t2 is cut out. Here, the cutting position is such that, when the formed head chip 1 is mounted on the head substrate 2, the area of the back side of the facing surface to the head substrate 2 is the magnetic recording medium sliding surface a side of the facing surface. It is set to be less than or equal to half the area of the portion fixed to the head substrate 2.

The winding window 13 of the head chip 1
After performing post-processing such as winding on the head chip 1,
Is mounted on the head substrate and fixed by adhesion to complete the magnetic head device. The magnetic head devices are mounted on the rotary drum 3 in pairs, for example. As described above, in the present embodiment, the magnetic core block 21 is ground to the predetermined depth D from the back side for each magnetic gap g to form each groove 33, and then each groove 33 is formed. Corresponding to, the polishing surface a ′ is narrower than the groove 33.
Each head chip 1 is cut out by grinding until it reaches the groove 33 from the side. At this time, in the manufactured head chip 1, the chip width t1 on the magnetic recording medium sliding surface a side is constant, and the back side chip width t2 is smaller than the chip width t1. . This state is shown in FIG.
Shown in Here, line segment ABC shows the shape near the back side of the conventional head chip, and line segment AB-D shows the shape near the back side of head chip 1.

Therefore, when the head chip 1 is bonded and fixed to the head substrate 2, as shown in FIG.
Since the surface of the head chip 1 facing the head substrate 2 is parallel to the head substrate 2 in the vicinity of the magnetic recording medium sliding surface a, the head chip 1 and the head substrate 2 are
The head chip 1 is installed without inclination between the magnetic recording medium and the magnetic recording medium, and the center of the curved surface of the sliding surface a of the magnetic recording medium slides with the magnetic recording medium during recording and reproduction. Therefore, extremely good recording / reproducing can be performed.

Further, in the present embodiment, when the magnetic head device is viewed from the side surface as shown in FIG. 10, the cut surface of the head chip 1 facing the head substrate 2 is formed by the grindstone 32. The head chip is manufactured so that the length k2 of the portion defined by the groove portion 33 is half or less of the length k1 of the facing surface. Therefore, the head chip 1 and the head substrate 2 can be more accurately and surely.
And will be placed in parallel.

[0022]

According to the present invention, it is possible to manufacture a magnetic head device capable of performing extremely good recording / reproducing without causing deviation in the center of the curved surface of the sliding surface of the magnetic recording medium of the head chip. it can.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a magnetic head device of this embodiment.

FIG. 2 is a perspective view schematically showing a head chip that is a component of the magnetic head device.

FIG. 3 is a perspective view schematically showing a state in which a pair of magnetic head devices is provided on a rotary drum.

FIG. 4 is a perspective view schematically showing a pair of magnetic core block halves.

FIG. 5 is a perspective view schematically showing a state in which a pair of magnetic core block halves are butted against each other via a gap film to produce a magnetic core block.

FIG. 6 is a perspective view schematically showing a state in which each groove is cut from the back side of the magnetic core block for each magnetic gap.

FIG. 7 is a side cross-sectional view schematically showing a state in which grinding is performed so as to correspond to each of the above-mentioned groove portions and narrower than the groove portions from the polishing surface side to reach the groove portions.

FIG. 8 is a perspective view schematically showing a state where the bottom of the magnetic core block is cut and cut into each head chip.

FIG. 9 is a side sectional view schematically showing the head chip.

FIG. 10 is a side sectional view schematically showing a bonded portion between the head chip and the head substrate.

FIG. 11 is a perspective view schematically showing a head chip which is a component of a conventional magnetic head device.

FIG. 12 is a perspective view schematically showing how a ground surface of a magnetic core block is ground when a conventional magnetic head device is manufactured.

FIG. 13 is a side sectional view showing an enlarged state of the grinding.

FIG. 14 is a side sectional view schematically showing a bonded portion between a head chip and a head substrate in a conventional magnetic head device.

[Explanation of symbols]

 1 head chip 2 head substrate 3 rotating drum 21 magnetic core block 33 groove

Claims (1)

[Claims] 1. A groove portion extending from a back side to a midway portion of the magnetic core block at a cutting position of a head chip with respect to a magnetic core block having a plurality of magnetic gaps formed on a polishing surface serving as a sliding surface of a magnetic recording medium. And a step of grinding each head chip by grinding until a groove is reached from the polishing surface side with a grindstone narrower than the groove corresponding to each groove, and installing the head chip on the head substrate. A method of manufacturing a magnetic head device, comprising: