JPH0363910A - Magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To prevent the generation of noises and the flawing of a tape by inclining both sides of the edges of an inner chip symmetrically and nonparallel with gap parts and forming flat parts of a narrow width on the front ends. CONSTITUTION:Grooves 17 for winding windows and grooves 16 for glass welding are formed in parallel on the nonmagnetic film side of a magnetic wafer 9. Grooves 18 for working track widths are then formed in parallel so as to intersect orthogonally with the grooves 17 for winding windows on the nonmagnetic side of the wafers 8, 9 and both substrates are press welded to each other. Ruggedness of a triangular peak is worked at the pitch of the gap parts 3 on the outside surface of the wafer 8 and slopes 5, 5 on both sides are inclined with the gap parts 3. The flat surfaces 6 of the narrow width are made to remain on the front ends thereof. The magnetic head produced by cutting the press-welded body of the wafers is inclined on both sides of the edges 5 of the inner chip 2 symmetrically and nonparallel with the gap parts 3 and is formed with the flat parts 6 of the narrow width at the front end. The generation of noises and the flawing of the tape are prevented in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a magnetic head and a beam used in a VTR or the like.

(Prior Art) Conventionally, in the case of a double azimuth head in a magnetic head used in a VTR or the like, two magnetic head chips are arranged close to each other on a chip base. The magnetic tape moves closely across the sliding surfaces of the two magnetic heads, and at this time the inner edge of the magnetic head comes into strong contact with the tape, so this is a part that should not normally be involved in recording and playback. Nevertheless, it acts as a kind of pseudo gap, picking up signals from the same azimuth head and generating vertical striped color noise on the screen. To prevent this, Fig. 22,
As shown in FIG. 23, the inner edge of the sliding surface is cut.

In the example shown in FIG. 22, when the magnetic wafer is in a block state, the edges of the block are subjected to a series of grinding processes. Since this is a manufacturing method in which processing is performed in the block state, manufacturing is simple and has the advantage that it can be applied to a plurality of magnetic heads at once. However, the edge after processing (
13) is formed parallel to the azimuth angle of the gap portion (3), so the noise prevention effect cannot be said to be sufficient.

In the example shown in Fig. 23, a pair of head chips (1), (2), and (la), (2a) are first produced in an unprocessed state from a magnetic wafer, and then fixed onto a head base to complete the process. 28) is applied to the inner edge of the head chip and moved parallel to the chip base, thereby forming a cut edge (13) that is not parallel to the gap portion (3).

In this embodiment, the cut edge (13) is the gap part (3).
Since they are non-parallel, the noise prevention effect is high and a magnetic head with high performance can be manufactured. However, this cannot be carried out at the block state stage in the middle of the manufacturing process, and is carried out as the final stage after the head chip is completed and fixed to the head base, which is time-consuming and has low production efficiency.

Furthermore, since the cut edge (13) is perpendicular to the sliding direction of the tape, there is a problem in that dirt tends to adhere to the cut edge (13).

24 aSbSc
An example of the magnetic head shown in FIG. The example in Figure 24a shows the inner edge (13) of the inner head tip (2).
was provided non-parallel to the gap portion (3) in order to reduce noise.

In the example shown in FIG. 24, both sides of the inner head chip (2) are symmetrically inclined and are non-parallel to the gap portion (3).

The magnetic head in Figure 24C has an inner head chip (2).
is made as thin as the width of the gap portion (3), and the inner edge (13) is made non-parallel to the gap portion (3).

As for the magnetic head shown in FIG. 24 aSbSc, the manufacturing method thereof is not disclosed, and furthermore, since the inner edge (13) of the head portion shown in FIG. When sliding in contact with the contact surface, there is a problem in that the tip of the inner edge easily damages the tape.

In the magnetic head shown in FIG. 24C, the inner head chip (2) is cut to a narrow width comparable to the track width, which reduces its strength and makes it prone to wear.

(Problems to be Solved) An object of the present invention is to prevent the edge of the inner head chip from causing noise and damaging the magnetic tape when it comes into sliding contact with the magnetic tape in a double azimuth head type magnetic head. The purpose of this paper is to clarify the manufacturing method of the magnetic head.

(Means for Solving the Problem 1) A first example of the magnetic head of the present invention (FIG. 1) has a tape-sliding surface of the head chip (2) tapered inward from both sides of the inner edge toward the center. It is inclined non-parallel to the gap portion (3) and has a flat surface (6) at the tip of the inner edge (5).

The above magnetic head is manufactured by forming the non-magnetic film (14) on the surfaces of the magnetic wafers (8) and (9) (Fig. 4), and then applying the , a winding window groove (17) and a glass welding groove (16) are formed in parallel (FIG. 5).

Next, track width grooves (18) are left on the non-magnetic film side surfaces of the two wafers (8) (9) in a direction perpendicular to the winding window groove (17). ) are formed parallel to each other (Fig. 6). 2 magnetic wafers (8)
(9) are placed on top of each other with the surfaces of the non-magnetic film (14), positioned so that the track width stripes (20) coincide with each other, and pressure and heat are applied to bond them together (FIG. 7).

Of the two wafers crimped together, the gap portion (
3) Process the unevenness of the triangular ridge at the pitch (Fig. 8),
The sloped surfaces (5) (5) on both sides are sloped with respect to the gap (3), and the tips of the sloped surfaces (5) (5) are not sharp, leaving a narrow flat surface (6).

The crimped wafer body is cut (24) at the pitch of the winding window grooves (17) and perpendicular to the unevenness of the triangular ridges to obtain a rod-shaped block body as shown in FIG. After the sliding surface is curved (h), the magnetic head is cut at the pitch of the gap portion (3) and at a predetermined azimuth angle α (26).One magnetic head shown in FIG. 1 is manufactured.

Figure 2 shows the glass melting part (4) in the magnetic head shown in Figure 1.
), and when the magnetic head is viewed from the front, the width of the glass melting part (4) gradually decreases from the tape sliding contact surface to the winding window groove (17) side, making it a flat surface. The figure is Figure 1a
It is similar to

(Operation and Effect of Means 1) In the magnetic head, both sides of the edge (5) of the inner chip (2) are inclined symmetrically and non-parallel to the gap part (3), and the tip has a narrow width (approximately the track width). 1/3) of the flat part (6
), even if the magnetic tape moves on the sliding surface, the inner edge has a flat tip (6), so the tape will not be damaged, and the head will not be damaged by magnetic powder adhering to the head. Can prevent dirt.

(Means for Solving 2) In a second example (FIG. 10) of the magnetic head of the present invention, the inner edge (30) of the inner head chip (2) is formed in a parabolic or elliptical shape, and the edge (30) is formed in a parabolic or elliptical shape. ) is characterized by a magnetic head whose height is lower than the sliding surface.

The manufacturing of the magnetic head described above is the same as that of the first example of the magnetic head of the present invention. Two wafers (8) (
In addition to forming a non-magnetic film on 9), one wafer surface is processed with a gear part, and the other wafer surface is processed with a gear part and a groove for a winding window and a groove for molten glass,
The protrusions of the two wafers are positioned and crimped to form a crimped body (FIG. 7). No grooves are formed on the surface of the crimped body,
It is then sliced at the pitch of the winding window groove to obtain a bar-shaped block (Fig. 11). After applying a curved surface to the tape sliding contact surface of the rod-shaped block, cut grooves (32) are formed diagonally at the pitch of the gap portion (3) in a portion corresponding to the inside edge (30) of the inside tip (8). , protrusions (34) having a slightly wider width than the gap portion (3) are formed at the same regular intervals as the gap portion (3) (FIG. 12).

The polishing tape (36) is applied diagonally to the protrusion (34) and the tape is moved so as to cover the sliding surface, tip, and both edges of the protrusion (34) (FIG. 13).

When each protrusion was formed by cutting, it had a rectangular and angular shape, but by polishing with the polishing tape (36), the sliding contact surface of each protrusion (34) was polished. The height decreases and the edges on both sides and the top edge become parabolic or elliptical curved surfaces.

(Effect of Means 2) Since the sliding contact surface of the convex strip (34) on the inner chip of the magnetic head is polished and its height is reduced, the magnetic tape passing through the sliding contact surface of the magnetic head is placed on the inner edge (30). do not come into contact with each other, so the magnetic tape will not be scratched or magnetic powder will stick to it. Moreover, since the edge (30) of the inner chip has a parabolic or elliptical shape, it is non-parallel to the edge part (3), and the noise prevention effect can be enhanced.

(Means for Solving 3) In the third example (FIG. 15) of the magnetic head of the present invention, the tip edge (36) of the inner head chip (2) is connected to the gap portion (3).
It is formed at a reverse azimuth angle. According to the method of the present invention, the edge portion (36) is formed with respect to the edge straight line A at the opposite azimuth angle with respect to the inclination of the azimuth angle of the gap portion (3), or with respect to the edge C parallel to the gap portion (3) or the chip base. It can be formed at any angle like a vertical straight line B. If the edge (36) is a straight line C, the second
It corresponds to the shape in Figure 2a. The straight line B corresponds to the shape shown in FIG. 23a.

The manufacturing method of the magnetic head described above is the same as the manufacturing method in the first example of the present invention up to the step shown in FIG. 7 in which two wafers (8) and (9) are bonded together. After that, the gap part (3) is formed on the outer surface of the wafer on the side where the winding window groove (17) is not formed.
Serrated grooves (38) are formed at a pitch of (Fig. 17).

Next, the crimped wafer is sliced at the pitch of the winding window grooves to obtain bar-shaped blocks (FIG. 18). This is the gap part (3
) and slice it at a predetermined azimuth angle to form a sawtooth groove (38).
The etching tip shown in FIG. 15 is obtained, with the slope of the tip as the tip edge. As shown in FIGS. 19'a and 19'b, the head chip has a sawtooth groove slope (38) formed at an angle of the tip edge (36) over the entire vertical height.

Figures 20 and 21 show a modification of the third example, in which sawtooth grooves (40) are applied only to the portion of the wafer crimped body that corresponds to the tip edge of the inner wafer (8). It is something. This is sliced to form a rod-shaped block and further cut to obtain the magnetic head piece shown in FIG. 21aSb. The tip edge (36) of the inner head chip (2) of the magnetic head is a slope of a sawtooth groove up to a step (42) in the middle, but the thickness below is the thickness of the head chip (2).

(Operation and Effect of the Third Means) The manufacturing method of the third example of the present invention is such that the tip edge of the magnetic head chip is formed by setting the slope of the sawtooth groove (38) formed on the outer surface of the wafer crimped body to an appropriate desired angle. The angle can be changed freely.

For example, as shown in FIG.
As shown in Figure 3, the shape cannot be processed by polishing with a diamond grinder (28), but with the present invention, the wafer can be processed while it is in a block state during the manufacturing process, so a large number of magnetic head chips can be processed at once. Done,
Production efficiency improves.

(Example) Since the details of the present application are clear from the description of the first to eighth means, a new description of the example will be omitted.

The material of the magnetic wafers (8) and (9) is ferrite, and the non-magnetic film formed on the surface of the magnetic wafers (8) and (9) is made of silicon dioxide (Sing) by sputtering deposition or the like.

Also, the side surfaces (lO
)(12) is a reference plane for processing the track width processing groove (18), the winding window groove (17), and the winding window groove (17) at right angles to the nonmagnetic film processing surface. It has a mirror finish.

Since the dimensions of the magnetic head of the present invention are not significantly different from those of conventional magnetic heads of this type, specific dimensions will also be omitted.

Furthermore, as shown in FIG. 7, two wafers (8) (9)
When the surfaces of the non-magnetic films of
8) If the thicknesses of (9) are the same, polish the wafer (8) on the side that does not have the winding window groove to obtain the desired block width l as shown in FIG. This also applies to the second and third means.

Note that the drawings and the above description are provided for understanding the present invention, and should not be used to narrowly interpret the scope of the claims.

[Brief explanation of drawings]

1aSb is a front view and a plan view of the magnetic head of the first example of the present invention, FIG. 2 is a plan view of another embodiment of the glass melting part (4) in the magnetic head of FIG. 3 to 9 are explanatory diagrams of the manufacturing method, FIG. 10 a1b is a front view and a plan view of a second example of the magnetic head according to the present invention, FIGS. 11 to 14 are explanatory diagrams showing the manufacturing method, and FIG. 15 16 is a front view of a product obtained by implementing the third example of the method of the present invention, FIGS. 17 to 19 are explanatory views showing the manufacturing method, and FIGS. 20 and 21 are front views of a product obtained by implementing the third example of the method of the present invention. The explanatory diagrams of other embodiments, FIG. 22 a1b to FIG. 24 a, b, and c, are front and plan views of conventionally known magnetic heads. (8) (9) ... Magnetic wafer (16) ... Glass welding groove (18) ... Track width processing (32) ... Cut groove (36) ... Polishing tape (14) ...Nonmagnetic film (17)...Window window groove (30)...Tip edge (34)...Protrusion (38)...Sawtooth groove

Claims (1)

[Claims] [1] The inner and outer head chips (1) and (2) are connected to the gap portion (3).
) In a double azimuth magnetic head in which a pair of magnetic head pieces formed by butting and crimping are arranged close to each other on the same line, the inner edge (5) of the inner magnetic head piece of each magnetic head piece (5) ) is tapered from both sides toward the center and provided obliquely and non-parallel to the gap portion (3), and is provided with a tapered and narrow flat portion (6). [2] Non-magnetic film (1) on the surface of magnetic wafer (8) (9)
4) Forming a winding window groove (17) and a glass welding groove (16) in parallel on the non-magnetic film side surface of one wafer (9), and forming the winding window groove ( Step 17) of forming track width grooves (18) leaving track width grooves (20) in the direction orthogonal to wafer 17); similar track width processing on the non-magnetic film side surface of the other wafer (8); a step of overlapping the surfaces of the nonmagnetic films of the two wafers (8) and (9), positioning and pressing so that the track width ridges (20) coincide with each other; Of the two crimped wafers, the outer surface of the wafer (8) that does not have the winding window groove is processed to have triangular peaks at the pitch of the gap (3), and the slopes on both sides of each peak are formed. (5
) (5) is inclined with respect to the gap part (3) and the inclined surface (5) The tip of (5) is not sharp but a narrow flat surface (6)
A step of cutting the wafer crimped body at the pitch of the winding window groove (17) and perpendicular to the unevenness of the triangular crest to form a bar-shaped block body, including a gap part (3) of the bar-shaped block body. A method for manufacturing a magnetic head, comprising the steps of: applying a curved surface to the tape sliding surface on the end face; and cutting a rod-shaped block body at the pitch of the gap portion (3) and at a predetermined azimuth angle to form a magnetic head piece. [3] Connect the inner and outer head chips (1) and (2) to the gap part (3
) In a double azimuth magnetic head in which magnetic head pieces are butted and crimped to form a sliding contact surface of the magnetic tape including a gap portion (3) and arranged close to each other on the same line, the inner side of each magnetic head piece is A magnetic head characterized in that the inner edge (30) of the magnetic head piece is formed into a radial or elliptical curved surface, and the height of the edge (30) is lower than the sliding surface. [4] Non-magnetic film (1) on the surface of the magnetic wafer (8) (9)
4) Forming a winding window groove (17) and a glass welding groove (16) in parallel on the non-magnetic film side surface of one wafer (9), and forming the winding window groove ( Step 17) of forming track width grooves (18) leaving track width grooves (20) in the direction orthogonal to wafer 17); similar track width processing on the non-magnetic film side surface of the other wafer (8); a step of overlapping the surfaces of the nonmagnetic films of the two wafers (8) and (9), positioning and pressing so that the track width ridges (20) coincide with each other; Of the two wafers that have been crimped together, on the edge of the wafer (8) that does not have the winding window groove, the pitch is the same as that of the gap section (3), and the depth is deeper on the gap section (3) side. A step of forming diagonal cut grooves (32) and forming protrusions (34) between the grooves (32) corresponding to the gap portions (3), each protrusion (3)
4) is polished by applying an elastic abrasive material (36) to lower the upper surface of the protruding strip (34) than the sliding surface, and to lower the upper surface of the protruding strip (34).
) and the tip edge (30) are formed into curved surfaces. [5] Non-magnetic film (1) on the surface of the magnetic wafer (8) (9)
4) Forming a winding window groove (17) and a glass welding groove (16) in parallel on the non-magnetic film side surface of one wafer (9), and forming the winding window groove ( Step 17) of forming track width grooves (18) leaving track width grooves (20) in the direction orthogonal to wafer 17); similar track width processing on the non-magnetic film side surface of the other wafer (8); a step of overlapping the nonmagnetic film surfaces of the two wafers (8) and (9), positioning and pressing so that the track width ridges (20) coincide with each other; Of the two crimped wafers, on the outer surface of the wafer (8) on the side that does not have the winding window groove, a predetermined groove is placed at the pitch of the gap part (3) and in a direction orthogonal to the direction of the winding window groove. A step of forming an inclined sawtooth groove (38), A step of cutting the crimp body of the wafer at the pitch of the winding window groove (17) and perpendicular to the sawtooth groove (38) to form a bar-shaped block body. A process of applying a curved tape sliding surface to the end face including the gap part (3) of the block body. A process of cutting the rod-shaped block body at the pitch of the gap part (3) and at a predetermined azimuth angle to form a magnetic head piece. A method for manufacturing a magnetic head characterized by the following.