JPH0630127B2 - Magnetic head manufacturing method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a magnetic head, and more particularly to a method for manufacturing a magnetic head which is suitable for use in obtaining a double azimuth head.

2. Description of the Related Art There are some video tape recorders in which still reproduction is performed by so-called field still to obtain a reproduced image without noise. As shown in FIG. 1, a video tape recorder using this field still has a rotating body (1) rotating in the direction of arrow a, for example, 180 ° from each other.
The magnetic head H _A and the magnetic head H _B are arranged at an angular interval of, and one of the magnetic heads H _A has a magnetic gap g _A of, for example, as shown in its schematic front view in FIG. The magnetic head H _B has a structure in which a predetermined angle α / 2 is tilted clockwise with respect to a vertical plane including the rotation center axis (hereinafter, the tilt in this direction is referred to as plus azimuth).
As shown in the schematic front view of the figure, the first magnetic gap g _B1 and the positive azimuth + α / having two first and second magnetic gaps having negative inclinations, that is, minus azimuth −α / 2. A double azimuth head configuration with a magnetic gap g _B2 with ₂ . During normal recording / playback, the recording / playback is performed by the magnetic head g _A of plus azimuth of both magnetic heads H _A and H _B and the first magnetic gap g _B1 of minus azimuth, but at the time of still playback. Used by the combination of the magnetic gap g _A by plus azimuth and the second magnetic gap g _{B2 in} the respective magnetic gaps H _A and H _B , the signal is taken out only from the magnetic tracks having the same azimuth, so-called field still. By doing so, noise generation due to the difference in azimuth between the reproducing head and the recording track is avoided.

A double azimuth head H _B having a magnetic gap of plus azimuth and minus azimuth used in a video tape recorder having such a field still function is
Its magnetic core _{c 1} and _c 1 of the first and second magnetic gaps g _B1 and g _B2 are each pair of first and second head elements constituted by butted a ', _{c 2} and _{c 2' h 1} , H ₂ are mounted on a common base.
The work of mounting the two head elements h ₁ and h ₂ on the head base by performing azimuth adjustment, height adjustment, etc. in a predetermined positional relationship with each other is extremely troublesome, and not only hinders mass productivity but also has a drawback of low reliability. is there.

SUMMARY OF THE INVENTION The present invention relates to a magnetic head manufacturing method suitable for obtaining a double azimuth head used in a video tape recorder having a field still function as described above, and solves the above-mentioned drawbacks. It is a thing.

SUMMARY OF THE INVENTION A step of producing a joined body by joining a first core block having a first magnetic gap formed therein and a second core block having a second magnetic gap formed therein, and from the joined body And a head chip cutting step of cutting out the head chip having the first and second magnetic gaps.

And the first core block has the first magnetic gap
A magnetic gap having no azimuth angle parallel to the joint surfaces of the first and second core blocks forming the joined body is used, and the second core block has the second magnetic gap formed by the joined body. It is a magnetic gap having a required azimuth angle α with respect to the joint surfaces of the first and second core blocks that constitute it.

Then, the first and second magnetic gaps of the head chip cut out from the bonded body are formed with the required azimuth angle α.

Embodiment In the present invention, as described above, the first head core block forming the magnetic gap without azimuth and the second head core block forming the magnetic gap having a predetermined azimuth are provided. First, the first head core block will be described. This core block is composed of a pair of core block halves (1c ₁ ) made of a magnetic material, for example, magnetic ferrite, as shown in the perspective view of FIG.
And (1c ₂ ) are provided. One of the block halves (1c ₁ ) is composed of, for example, a rectangular parallelepiped block having a relatively large thickness, while the other block halves (1c ₂ ) is composed of a relatively thin plate-shaped magnetic body. The core block halves (1c ₁ ) and (1c ₂ ) are joined together at one side surface thereof to form the first head core block (1), as shown in FIG. But these core halves (1
c ₁ ) and (1c ₂ ) at least one butt joint surface of each other, but in the illustrated example, both core halves (1c ₁ ) and (1c ₂ ) are shown in FIG. 4 on their respective joint surfaces. In this way, a plurality of track width regulating grooves (2) extending in one direction to regulate the track width are formed at a predetermined interval. Then, as shown in the perspective view of FIG. 5, both block halves (1c ₁ ) and (1c ₂ ) are filled with glass (16) in the track width regulating grooves (2) (2c). 1c ₁ ) and (1c ₂ ) are joined and joined together, and in this joined state, the respective track width regulating grooves (2) are made to face each other to form, for example, a cylindrical groove, and between the adjacent grooves (2) _First core gaps (1c ₁ ) and (1c ₂ ) are butted to form a _first magnetic gap g ₁ in a straight line. Then, in the first core block (1), for example, the outer surface of the plate-shaped block half body (1c ₂ ) is mirror-finished to be flat, and this is joined to the other second core block described later. (1a) is formed. In addition, here, the arrangement surface of each magnetic gap g ₁ of the first core block (1), that is, the joint surface between both block halves (1c ₁ ) and (1c ₂ ) is the first block (1). 1)
Of the second head core block is parallel to the joint surface (1a) with the other second head core block.

At least one core half (1c ₁ ) of the core block (1) regulates the depth of the magnetic gap g ₁ and finally the winding groove (8) in which the head winding is inserted and wound. ) Is formed to extend in the direction crossing the groove (2).

On the other hand, in the present invention, the second head core block having the second magnetic gap having the predetermined azimuth α is formed. The second head core block can be formed by a predetermined method, and can be configured by a core chip portion forming a magnetic gap having azimuth α and a supporting portion thereof. An example in this case will be described. In this case, as shown in its exploded perspective view in FIG. 6, it has a side surface (3a) corresponding to the side surface (1a) of the core block (1) described in FIG. A rectangular parallelepiped support part (3) is provided. This support part (3) has a core chip part, respectively.
A plurality of chip insertion grooves (5) for inserting (4) and supporting the same at predetermined positions are formed in parallel while maintaining a predetermined interval. The core chip section (4) is composed of a pair of core chip halves (4
c ₁ ) and (4c ₂ ) are joined together so as to face each other, and a second magnetic gap g ₂ is formed between the abutting surfaces of both. (6) is the magnetic gap g ₂ of each core chip (4)
In this case also, the glass (16) is filled in the groove (6) with the track width restricting groove for restricting the track width. (7) is a winding groove that regulates the depth of the magnetic gap g ₂ and is finally used for winding the head winding, for example, a direction crossing the groove (6) in one core chip half (4c ₂ ). The core chip portion (4) formed by extension can be prepared by preparing a core block having the same structure as described with reference to FIG. 5 and cutting it out obliquely.

As shown in the perspective view of FIG. 7, these core chip portions (4) are inserted into and joined to the respective chip insertion grooves (5) of the supporting portion (3) to form the second head block (9). Composed. The core chip portion (4) and the supporting portion (3) can be joined by fusion of low melting point glass between the core chip portion (4) and the supporting portion (3) so as not to block the winding groove (7).

Here, the core chip portion (4) is made of a magnetic material such as ferrite, and the support portion (3) has a coefficient of thermal expansion of the core chip portion (4).
It is composed of a material similar to that of, for example, magnetic ferrite of the same material as the chip portion (4) or non-magnetic ferrite of the same quality.

Then, the joint surface (9a) of the second head block (9) with the first core block (1) is mirror-finished to be flat, and both core blocks (1) and ( 9) on each side (1
In a) and (9b), the blocks (1) and (9) are joined to each other via a non-magnetic spacer (10) having a required thickness, for example, a glass spacer (10) to form a joined body (11). obtain. This glass spacer (10) is coated with glass paste on both sides in advance, and in a state in which both blocks (1) and (9) are pressed against each other with the glass spacer (10) sandwiched between them, the glass paste is heated. , The block (1), the spacer (10) and the block (9) are joined together.

As described above, according to the present invention, the first head core block (1) and the second head core block (9) are joined together. The extending direction of the gap g ₂ , that is, the track width direction, is the joint surface (9a) with the first head core block (1).
On the other hand, as shown in FIG. 9, it is formed so as to have a predetermined azimuth α. First, in the core chip portion (4) itself, the gap g ₂ is formed so as to have an angle α / 2 of 1/2 of a predetermined azimuth α with respect to the thickness direction. Further, the extending direction of the groove (5) into which the tip portion (4) of the support portion (3) is inserted is selected so as to form an angle of α / 2 with respect to the normal to the surface (9a). By inserting the core chip part (4) having a gap g ₂ with α / 2 azimuth into the groove (5), the magnetic gap g ₂ of the chip part (4) is changed to the surface (9a).
, That is, the magnetic gap g ₁ has a predetermined azimuth α. In this case, the azimuth of the gap g ₂ can be reduced in the core chip portion (4) itself, which facilitates its manufacture and improves the accuracy. Furthermore, this core chip part (4)
It is possible to avoid damage due to sharp edges of the abutting surfaces of the core chip halves (4c ₁ ) and (4c ₂ ) constituting the.

Next, from the thus obtained joint body (11), as shown by chain lines in FIGS. 8 and 9, both blocks (1) and (9)
Of the first block (1) formed with no azimuth in the above-mentioned first block (1) by cutting out at a required angle with respect to a plane perpendicular to the joining surface of A head chip (12) cut out so that the magnetic gap g ₁ has an azimuth of −α / 2 is obtained. When cutting out the head chip (12), the support portion (3) is cut off. 10 and 11 are an enlarged perspective view and a front view, respectively, of the head chip (12). Winding grooves (13) are cut on both side surfaces of the head chip (12).

Then, the front surface of the head chip (12) thus obtained is polished to form a contact surface (14) with the magnetic medium as shown in the enlarged perspective view of the twelfth, and Wire groove (8) and
Head winding across the winding hole by (7) and each winding groove (13)
The target magnetic head can be obtained by winding (15).

The magnetic head thus obtained has the first and second magnetic heads.
Magnetic gaps g ₁ and g ₂ of −α / 2 and α / 2, respectively.
With azimuth.

In the above-mentioned example, the arrangement of the grooves (5) of the support portion (3) of the second block (9) is such that the interlocking of the comb teeth formed between them faces the gap g ₂ . These grooves are formed when they are connected to each other on the surface opposite to the surface.
In the shape of (5), the comb teeth between them are connected on the side opposite to the side surface (3a), that is, the groove (5) is formed on the side surface (3a).
Various modifications and changes can be made such that the surface adjacent to the gap g _{1 in} a) and the opposite side surface can be formed.

As described above, according to the present invention, in a magnetic head having a double azimuth, a so-called double azimuth type in which magnetic heads are integrated in respective block bodies and then cut to have opposite azimuths Since the magnetic head of FIG. 2 is configured, the positional relationship between the two is further adjusted as compared with the conventional configuration in which head chips each having a magnetic gap are joined to each other to form a double azimuth type magnetic head. Since it is possible to avoid handling of a fine head chip for joining the both, it is possible to obtain a highly reliable magnetic head which has high mass productivity and avoids breakage during handling.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a rotary magnetic head device used for explaining the present invention, FIGS. 2 and 3 are schematic surface views of the head portion, and FIGS. 4 to 12 are diagrams according to the present invention. FIG. 7 is a process chart showing an example of a method of manufacturing a magnetic head. g ₁ and g ₂ are first and second magnetic gaps having mutually opposite azimuths, (1) and (9) are first and second core blocks, and (11) is these first and second magnetic blocks. The bonded body of core blocks, (12) is a head chip.

Claims (1)

[Claims] 1. A step of producing a joined body by joining a first core block having a first magnetic gap and a second core block having a second magnetic gap, and the joining. A head chip cutting step of cutting a head chip having the first and second magnetic gaps from a body, wherein the first core block has the first magnetic gap forming the bonded body. The first and second core blocks are magnetic gaps that are parallel to the joint surface and have no azimuth angle, and the second core block has the second magnetic gap that constitutes the joint body. And a magnetic gap having a required azimuth angle α with respect to the joint surface of the second core block, and in the head chip cut out from the joint, the first and second magnetic gaps are Method of manufacturing a magnetic head, characterized in that it has to be formed with the desired azimuth angle α to.