JPS6134579Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a magnetic head device, particularly to a magnetic head device used in a video signal magnetic recording/reproducing device.

In general, magnetic head devices used in video signal magnetic recording and reproducing devices have extremely small magnetic heads, so the magnetic head is attached to a substrate made of a non-magnetic material so as to protrude from the front end surface of the substrate. screwed onto the rotating disk surface. At this time, since the surface of the rotating disk becomes the reference surface for mounting the magnetic head, it is necessary to make the adhesive film between the magnetic head and the substrate as thin as possible, so liquid cyanoacrylate-based instant adhesive is used as the adhesive. hand,
The adhesive film thickness is kept at 4 μm or less.

FIG. 1 is a front view showing a conventional magnetic head device.
FIG. 2 is a cross-sectional view of FIG. 1. In the figure, 1 is a board, 1a is a screw fixing hole provided in the board 1, 2 is a terminal board glued to the board 1, and 3 is a board 1
A magnetic head 3a is bonded to the front end surface 1b of the substrate 1 while protruding from the front end surface 1b.A winding window 3a is provided in the magnetic head 3, and the winding window 3a is located forward of the front end surface 1b of the substrate 1. 4 is an adhesive.

In this magnetic head device, in order to bond the magnetic head 3 to the substrate 1, the magnetic head 3 is first positioned on a positioning jig (not shown), the substrate 1 is placed on the magnetic head 3, and the substrate surface 1c of the substrate 1 is pressed against the magnetic head 3 by a pressing jig (not shown).
Then, a small amount of adhesive 4 is applied to the tip of a thin cotton swab, and the adhesive 4 is dropped onto the front end surface 1b of the substrate 1 pressed against the magnetic head 3. The adhesive 4 then permeates the small gap between the substrate surface 1c and the magnetic head 3 by capillary action, and the magnetic head 3 is adhered to the substrate 1.

However, since the dimensions of the magnetic head 3 are minute, even if a small amount of adhesive 4 is dropped, the adhesive 4 may flow into the winding window 3a and block the winding window 3a, or the adhesive may 4 may flow onto the positioning jig and the magnetic head 3 and the positioning jig may be glued together. Therefore, the workability of this bonding work is poor, and the yield in the bonding work is also poor. Furthermore, when dropping the adhesive 4 onto the front end surface 1b, the adhesive 4 can be dropped only over the width of the magnetic head 3, so the amount of adhesive 4 penetrating between the substrate 1 and the magnetic head 3 is limited. Since the area to which the adhesive 4 adheres is small, the adhesive strength is low.

This idea was made to solve the above-mentioned problems, and the purpose is to provide a magnetic head device that has a high yield in bonding work between the substrate and the magnetic head, and has a high adhesive strength between the substrate and the magnetic head. shall be.

In order to achieve this purpose, in this invention, the front end surface of the part of the board to which the magnetic head is bonded has a cross-sectional area smaller than the bonding area with the magnetic head, and the part of the board that is attached to the magnetic head has a cross-sectional area that is smaller than the bonding area with the magnetic head. Provide a notch that does not extend.

FIG. 3 is a front view showing the magnetic head device according to this invention. In the figure, 1d is an adhesive part of the substrate 1 to which the magnetic head 3 is attached, and 5 is a semicircular notch provided on the front end surface 1b of the adhesive part 1d. The notch 5 does not extend beyond the rear end of the magnetic head 3.

With this structure, if a small amount of adhesive 4 is dropped into the notch 5, the adhesive 4 will accumulate in the notch 5 due to surface tension, so that the adhesive 4 can be applied to the winding window as in the conventional case. The magnetic head 3 can be bonded to the substrate surface 1c of the substrate 1 without leaking onto the substrate 3a or onto the positioning jig. Also, the notch 5
By providing the adhesive 4, the length of the part where the adhesive 4 should penetrate becomes longer, so that the substrate 1 and the magnetic head 3
Since the amount of adhesive 4 that permeates between the two and the adhesive 4 increases and the area to which the adhesive 4 adheres increases, the adhesive strength is high.

Further, since the notch 5 does not extend further back than the rear end of the magnetic head 3, the adhesive 4 flows out from the rear end of the magnetic head 3 onto the positioning jig, and the adhesive 4 flows between the magnetic head 3 and the positioning jig. Since the adhesive part 1d of the substrate 1 is not easily deformed, the adhesive part of the magnetic head 3 and the adhesive part between the adhesive part 1d and the magnetic head 3 will not come off, and the magnetic head 3 will not be damaged.

In the above-described embodiment, the shape of the notch is semicircular, but the same effect can be obtained by changing the shape of the notch to a triangle, a quadrangle, or the like.

As explained above, in the magnetic head device according to the present invention, a notch having a cross-sectional area smaller than the bonding area to the magnetic head is provided on the front end surface of the part of the substrate to which the magnetic head is bonded. It is possible to prevent the wire from flowing into the winding window and onto the positioning jig, improving the yield in bonding work and improving the workability of bonding work. Furthermore, the adhesion area of the adhesive is large, and the adhesive strength between the substrate and the magnetic head is high. In this way, the effects of this invention are remarkable.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a conventional magnetic head device.
FIG. 2 is a cross-sectional view taken from FIG. 1, and FIG. 3 is a front view showing the magnetic head device according to this invention. DESCRIPTION OF SYMBOLS 1... Board, 1b... Front end surface, 1d... Adhesive part, 3... Magnetic head, 3a... Winding window, 4...
Adhesive, 5...notch.

Claims (1)

[Scope of utility model registration request] The magnetic head is placed on top of a non-magnetic substrate with the front end protruding from the front end, and adhesive is dripped onto the front end of the substrate in contact with the magnetic head, allowing the adhesive to penetrate between the magnetic head and the board by capillary action. In a magnetic head device in which a winding window is provided in front of the front end surface of the substrate of the magnetic head, on the front end surface of the portion of the substrate to which the magnetic head is bonded,
A magnetic head device characterized in that a notch is provided which has a cross-sectional area smaller than the adhesive area with the magnetic head and does not extend rearward beyond the rear end of the magnetic head.