JPH0261806A - Magnetic head device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [First aspect of the invention] (Industrial application field) The present invention relates to a magnetic head device used in a magnetic recording/reproducing device, such as a video tape recorder, and particularly relates to a magnetic head device used in a magnetic recording/reproducing device, such as a video tape recorder. 150 is applied to a magnetic head device that prevents unnecessary filling of bonding adhesive into the winding groove when bonding the wires.

(Prior art) Magnetic recording and reproducing devices (hereinafter referred to as VT) such as video tape recorders
FIG. 9 shows a conventional electric head used in a conventional electric head (referred to as R).

The air head 1 shown in FIG. 9 has a pair of core halves la, 1.
It is constructed by joining b. The curved surface on the 1111 side polished in an arc shape (σl) is the sliding surface with the recording medium, and a gap 5 having a predetermined track width TW is formed in the center. half body 1a
, lb track width regulation hi 3
J: is determined for a, 3 Fl and 3b, 3b.

3a, 3b, track width regulation)
When the core halves 1a' and 1b' in the locked state are abutted against each other, an abutment opening 3 is formed (see No. 10), and a gap 5 is formed between these openings 3. The track width regulating grooves 3a and 3b are tapered in the depth h direction of the gear 1/tube 5, and are filled with an inorganic adhesive 4 that joins the core halves 1a and 1b. ing.

As the inorganic adhesive 4, for example, a glass material is used. FIG. 10 is a perspective view illustrating the filling operation (A). The butted core halves 1a and lb have a groove 7, indicated by a dotted line, formed on the side that will become the sliding surface, in which the glass rod 4' is housed, and the glass rod 4' is placed in this groove 7 and heated. . by this,
Molten glass enters through the opening 3 and the insides of the track width regulating grooves 3a and 3b are clogged with the inorganic adhesive 4.

On the other hand, a winding groove 2 is formed in at least one of the core halves 1a and Ib. This winding groove 2 is formed at the tapered end portion of the track width regulating groove 3b, and after filling the track width regulating grooves 3a and 3b with the adhesive 4, the winding 6
is adapted to be passed through the winding groove 2.

However, before this filling, as shown in FIG. 11, the abutment is adjusted by 1 ls by the magnifying means of the optical microscope so that the track width regulations H63a and 3b match the track edges 10. (Track alignment).

In this way, the track width TW and the width I of the butt opening 3 are
A magnetic head is formed by slicing the magnetic head at equal intervals, where n is a constant bit interval -+l (W).

Incidentally, in recent years, with the development of magnetic recording technology, there has been a demand for heads with high conversion efficiency even in high bands. An improvement measure for such high frequency characteristics is to make the shortest magnetic path length of 10 fluxes Φ circulating around the winding surface 2 as short as possible, as shown in FIG. For this reason, the first
Shown in Figure 2! ,: Ratio between the cross-sectional area 8M of the winding groove 2 and the area STW of the butt opening 3 shown in FIG. 11<38/5TW
) is approximately 1 or less, ie, equal to or smaller than SHh<SrW, which is considered to be a good surface structure.

Here, SN, old Sr...■ S1'W = (KW - ds) + (K oath・dD)
...It can be determined by ■. Furthermore, the 12th
In the figure, KWH is the length of the long side of the trapezoid formed by the winding groove 2, KWB is the length of the short side, dH is the height, and ds is the track width regulating groove 3. In the track width regulating grooves a and 3b, dD represents the depth of the bottom tapered from the track edge.

However, if the winding) 14 area 8M and the butt opening area ST- are in the above relationship, when the adhesive 4 is filled from the groove 7, the adhesive 4 will be 1 to rack width regulating grooves 3a, 3bJ.
: It is also transmitted to the winding groove 2 side.

If the winding groove 2 is filled with the contacting material 4 unnecessarily, it becomes difficult to process the winding to remove the encroachment.

Further, in the conventional magnetic head, as the core half body 1a1b,
Since ferrite is used, the reflectance of light from a microscope is low, making it difficult to confirm track edges. This is the track width regulating groove 3a.

3b is tapered and light cannot be applied from the rear of the core half (sliding surface and half body side), and tIiS7
This is made more difficult by the fact that it is formed by grinding. FIG. 13 shows the bonded state when the track edges do not match. As shown in the circle with the arrow, the ]-rarak foot becomes inconsistent, making it impossible to accurately determine the track width T-.

(Problem to be Solved by the Invention) As explained above, the conventional magnetic head has two windings:
When trying to improve head efficiency suitable for high bands by reducing the IS, the contact @4 for joining the core halves is also within the line i+'i'+2 from the rack width regulation grooves 3a and 3b. Unnecessary filling will occur. (2) Due to the optical properties of the ferrite surface, there were problems such as difficulty in confirming the uniformity of ]-Rarac elas.

It is an object of the present invention to provide a magnetic head device which eliminates the above-mentioned problems, has good alignment accuracy between track width regulating grooves, and achieves magnetic conversion efficiency suitable for a high frequency band.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides an opening J formed by combining track width regulating grooves formed in each of the core halves, and filling both core halves with an adhesive. A magnetic head comprising two core halves that are joined together, a gap defining a predetermined track width is formed before joining without forming a track width regulating groove, and a winding wire is passed through a winding groove formed in at least one of the two core halves. The apparatus is characterized in that a metal film is formed on the wall surface of the winding groove to prevent the adhesive from moving from the track width control 4 to the winding groove.

(Function) According to this development, the metal film formed on the wall surface of the winding groove reduces the wettability of ferrite with the contacting material, so it regulates the fluidity of the adhesive. Prevents the collar material from moving 1J into the winding groove. Further, the metal film has a higher light reflectance than ferrite, and the light from the microscope is reflected by this metal film and transmitted through the track width ruler 1111 groove. Therefore, the track edges become clear.

(Example) The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 is a perspective view of an embodiment of a magnetic head device according to the present invention. In FIG. 1, reference numeral 11 indicates a magnetic head according to an embodiment of the present invention. This magnetic head 11 is made by joining core halves 11a and 11b together, as in the conventional case.
As for the material of each core body 11a, 11b, single-crystal or polycrystalline ferrite 1 to core is used as before.

In the 11712 bodies 11a and 11b, a gap 15 having a predetermined track width TW is formed at approximately medium temperature on the sliding surface.

On both sides of the grip 15, an abutment gap [A13] is formed by slicing the AY body in the block state and dividing it into halves.

The butt opening I 13 is tapered in the depth direction of the gap 15 from 1 to rack width regulation i, '/113.
a.

13b, and these track width regulating grooves 138°1. It is filled with an inorganic adhesive 14 such as a glass material that joins the L, 117 halves 11a and 11b together. Incidentally, in order to obtain the necessary depth Q, the gap 17 is filled with oxides such as 5102 (silicon oxide) and Zr02 (zirconium oxide) using a vacuum thin film forming technique.

On the other hand, at least one of the core halves 11a and 11b 1
11], a winding groove 12 is formed. This winding 11
412 is formed at the tapered end portion of the track width regulating groove 13b, as in the prior art. However, the difference from the configuration in FIG. 9 is that the wall surface forming the short side of the trapezoid, 111,
Sabe o Nari? A metal film 19 is formed on the J wall surface using the same vacuum thin film forming technique as the oxide film of the gap 15 described above.

Next, the magnetic head 11 having the above configuration was installed as 1JI81.
Explain the manufacturing process.

FIGS. 2 and 3 show a pre-process before joining.

First, referring to FIG. 2a, 21a and 21b are cores cut out at the crystal horn position, and in this figure, the upper surface is This becomes the abutting facing surface 20. The core half blocks 21a and 21b in this state are subjected to double-sided lapping processing so that the abutting and opposing surfaces 20 match in thickness TO.

Next, as shown in FIG. 2, the core half block 21a
, 21b, a lower winding groove 22 is formed at a predetermined depth on the abutting and opposing surface 20. This lower 11'' 422 is formed by, for example, grinding.Furthermore, the abutting opposing surface 20 on which the lower groove 22 is formed
A metal film 29 is formed on the body by a vacuum thin film forming technique such as sputtering. As this metal, for example, shiny copper, titanium, etc. are used. The standard film thickness tspr is 2 [μm] or less in consideration of distortion caused by film formation.

Next, as shown in FIG. 2, the metal film 2 other than the lower groove 22 is
The portion 9 is removed by double-sided lapping or mirror polishing. The thickness at this time is referred to as T1.

Historically, as shown in FIG. 2d, each core half block 21a
, 27a and 27b are formed on the part 1 and the moving surface of 21b, which are to be filled with glass A33.

Further, one surface of the lower 1t22 is made into a 1-pa shape. With this depth 22', the depth end of the gap 15 is determined.

Next, as shown in FIG.
, 23b. In this case, track width regulation 1g
23a and 23b are set at a predetermined angle θ along the depth direction.
■ becomes shallow. In addition, track width TW is determined by one pitch.
is determined. Next, the core half block 21a,
After cleaning 21b, a vacuum thin film is formed on at least one abutting and opposing surface 20 to form a retaining film such as 5i02 that retains the gap thickness q.

However, the retaining film has track width regulating grooves 23a and 23b.
form around.

FIG. 4 shows the core half blocks 21a and 21b of FIG. 3.
The Uk state is shown by comparing the values. In this state, optical microscope m 1
Perform track alignment according to 1. If there is a deviation in the track edge 30, move one of the core blocks to correct it. At this time, since the metal film 29 is formed in the lower groove 22 of the winding groove, when observed from the moving side 18, the illumination light is reflected on the surface of the metal film, and the track width regulating groove 23a,
It is transmitted through the abutting opening 23 by 23b. Therefore, the track edge 30 can be captured reliably, and highly accurate track alignment is possible.

Then, in this observation state, the glass rod 24' (see dotted line) is placed so as to span the grooves 27a and 27b, and heated in a predetermined atmosphere. As a result, as shown in FIG. 5, the glass rod 24' melts and becomes the adhesive 24, and the glass rod 24' is moved from the butt opening 23 to meet the rack width regulation 23a.

23b. At this time, a temperature condition is set where the glass flow stops at the depth end. Even when the glass flow is large, the effect of the metal film 29 formed in advance can prevent the glass from flowing into the lower ii+722 for the winding groove. This is because the wettability of the glass is ferrite and metal film 2.
Since there is a difference in darkness of 97, C, if you replace it, metal film 29
This is because the contact angle of glass on the surface of ferrite is larger than that of ferrite.

Contact angle is illustrated as shown in FIG. That is, it is one thinning angle θG of the glass 101 with respect to the sample substrate 102 at a predetermined temperature. This contact angle θG is 3 in the case of ferrite.
For example, in the case of copper, the angle is 40 to 120 degrees. The larger the contact angle θG is, the smaller the consistency is, and the fluidity of Glass 1 (N) is smaller.

This (111!I!) prevents the adhesive 24 from flowing into the lower groove 22, leaving a hole sufficient for the winding 16 to pass through. By polishing, adhesive 2
4 is removed, and the sliding surface has a predetermined curvature. As a result, the gap depth D (see Figure 5)
is set. Then, the block in FIG. 7 is further sliced along the dotted line.

This completes the core depth 31 as shown in FIG. At this time, the slice pitch PS is such that the azimuth angle is 0.
°, Ps = Pr may be sufficient. Further, when the azimuth angle is θ, Ps=PTcosθ is set.

Next, the winding 16 is wound around the adip 31 shown in FIG. 8 to form a coil, and the magnetic head 11 is completed.

In this manner, in the magnetic head of the embodiment, the area of the winding groove 12 is made smaller than the area of the abutment opening 13 (23) filled with glass, and a magnetic head with high band characteristics can be obtained. Further, when the area of the winding grooves is made small in this manner, the glass material flows and moves from the track width ruler 1+II grooves 23a and 23b, but this movement is prevented by the metal film 19. Therefore, it is easy to install the winding F1116, making it suitable for mass production. Furthermore, since track deviations can be observed accurately, it becomes easy to correct l/rack deviations.

[Advantageous Effects of the Invention 1] As explained above, according to the present invention, it is possible to mass-produce magnetic heads that are suitable for high band characteristics and have good conversion efficiency.

[Brief explanation of the drawing]

FIG. 1 is a perspective view, FIG. 2, FIG. 3, and FIG. 4 showing an embodiment of a magnetic head device according to the present invention. Figures 5, 7, and 8 are process diagrams for manufacturing the magnetic head shown in Figure 1. Figure 6 is an explanatory diagram explaining the fluidity of the glass material, and Figure 9 is a conventional Fig. 10 is a perspective view illustrating the structure of a conventional magnetic head, Fig. 11 is an explanatory drawing illustrating track alignment, and Fig. 12 shows a magnetic head with a high frequency band. FIG. 13 is an explanatory diagram illustrating a method for determining track deviation. 11... Magnetic head, 12 (22)... Winding groove, 1
3a. 13b (23a, 23b) -- Track width regulating groove, 14 (24) -- Stone contact material, 15 -- V-shaped groove, 16 -- Valley line, 19 (29) -- Metal film. Figure 2~'w -t 7'' Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 10 Figure 1 Figure 12 Figure 13

Claims (1)

[Scope of Claims] Both core halves are joined by filling an adhesive through an opening formed by aligning track width regulating grooves drilled in each of the core halves, and a joint surface where the track width regulating grooves are not formed. In a magnetic head device in which a gap having a predetermined track width is formed in the core half, and a winding wire is passed through a winding groove formed in at least one of the core halves, a wall surface of the winding groove is provided with a gap having a predetermined track width. A magnetic head device characterized in that a metal film is formed to dam the adhesive material moving into the winding groove.