JPH048843B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a track processing method for a magnetic recording head for a video tape recorder.

BACKGROUND ART As shown in FIG. 7, a conventional method for manufacturing a magnetic head for a video tape recorder is to apply a magnetic material 11 having a higher saturation magnetic flux density than that of the ferrite to the side surface of a ferrite block 10a, and then to As shown in FIG. 8, a predetermined number of cutting grooves 12 are formed in parallel on the side surface of the ferrite block 10a coated with the magnetic material using a diamond grindstone.
Next, as shown in FIG. 9, the two ferrite blocks 10a and 10b are joined together with their cut grooves 12 aligned using an ultrathin glass film (not shown) made of non-magnetic material, and used for recording and reproduction. A gapped bar 13 is formed. The upper surface of the cast bar 13 is precision machined, and the hole for forming the track is filled with glass. Next, as shown by the cutting line 14 in FIG. 10, cutting is performed at the cutting groove 12 portion, and the side surfaces are precisely finished to obtain the magnetic recording head shown in FIG. 11.

Problems to be Solved by the Invention However, the above configuration has the following problems.

(1) When forming the cutting groove, the ferrite block 1
The magnetic material 11 having a higher saturation magnetic flux density than ferrite is partially peeled off from 0a and 10b, resulting in deterioration of magnetic properties.

(2) Two ferrite blocks 10a and 10b
When bonding through thin film glass, if the relative positions of the cutting grooves shift, as shown in Figure 12,
The track width is reduced by the amount of discrepancy d, and the magnetic properties are degraded.

The present invention solves the above-mentioned problems and provides a method for processing a magnetic head that does not cause peeling of the magnetic material with high saturation magnetic flux density and also does not cause discrepancies in track width.

Means for Solving the Problems In order to solve the above problems, the method for processing a magnetic head of the present invention involves using a pair of ferrites, each of which has a magnetic layer having a higher saturation magnetic flux density than ferrite, on its side surface. The magnetic layers are opposed to each other, and a non-magnetic material is interposed between the opposed magnetic layers and bonded to form a gapped bar for recording and reproduction, and then a hole for forming a track is formed using a laser beam.

Effects The present invention has the above-described structure, and instead of forming track forming holes by machining using a conventional diamond grindstone, heat removal processing using a laser beam is used. This solves the problem of highly magnetic material peeling off during processing, and also solves the problem of discrepancies in track widths caused by forming holes for track formation after forming a capped bar for recording and reproducing. .

Embodiment An embodiment of the present invention will be described below based on the drawings. FIG. 2 shows a pair of magnetic materials 3a and 3b each made of high magnetic permeability ferrite, and one of the magnetic materials 3a has a winding groove 4 formed thereon. As shown in FIG. 3, these magnetic materials 3a and 3b are bonded together via a non-magnetic material (not shown) after a magnetic material 5 having a higher saturation magnetic flux density than ferrite is deposited on the side surface. , a gapped bar 6 for recording and reproduction is formed. After the upper surface of the recording/reproducing gapped bar 6 has been finished to be a smooth surface, a hole for forming a track is formed in the joint portion of the gapped bar 6 using a laser beam 1 across both magnetic materials 3a and 3b, as shown in FIG. 2 is formed. As the device for generating the laser beam 1, it is preferable to use a neodymium laser device, but the device is not limited thereto. Next, as shown in FIG. 4, after filling the track forming hole 2 with glass 7, the upper surface 9 is precisely machined, and the glass 7 is cut across the track forming hole 2 as shown by the cutting line 8 in FIG. After cutting and dividing, the cut surfaces are precisely finished to form the recording/reproducing magnetic head shown in FIG. 6.

The present invention can be configured in various ways other than those shown in the above embodiments. For example, in the above embodiment, the hole for forming the track is circular, but the present invention using a laser beam makes it possible to relatively freely define the shape of the hole, such as an ellipse or a rectangle. .

Effects of the Invention As described above, the present invention can achieve the following effects with the above configuration.

(1) Since the track forming holes are formed using a laser beam after the recording/reproducing gapped bar is formed, it is possible to eliminate the variation in effective track width that was a problem in the conventional example, and as a result, the magnetic head can improve the magnetic properties of

(2) When forming holes for track formation, the peeling of the magnetic material, which has a higher saturation magnetic flux density than ferrite, which was a problem with conventional processing using a diamond grinding wheel, was resolved by using laser beam processing. As a result, a high quality product is obtained.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a hole for track formation being processed with a laser beam, Fig. 2 is a perspective view of a ferrite block constituting the magnetic head of the present invention, and Fig. 3 is a diagram showing a ferrite block being machined with a non-magnetic material interposed therebetween. Figure 4 is a perspective view of the gapped bar formed by joining, Figure 4 is a diagram showing glass being filled into the track forming hole formed, Figure 5 is a diagram showing cutting of the gapped bar, and Figure 6 is a perspective view of the magnetic head. 7 to 11 are diagrams showing the manufacturing process of a conventional magnetic recording head, and FIG. 12 is a diagram showing the loss d in effective track width due to track misalignment. 1... Laser beam, 2... Hole for track formation,
3a, 3b...Ferrite block, 5...Magnetic material with higher saturation magnetic flux density than ferrite, 6...
Gap do bar.

Claims (1)

[Claims] 1 A magnetic layer having a higher saturation magnetic flux density than that of the ferrite is formed on the side surface of a ferrite block made of high magnetic permeability ferrite.
A gapped bar for recording and reproducing is formed by joining the pair with magnetic layers having a higher saturation magnetic flux density than ferrite facing each other, and interposing a non-magnetic material between the opposed magnetic layers having a high saturation magnetic flux density, A track processing method for a magnetic head that then uses a laser beam to form holes for track formation.