JPS5919210A - Magnetic head - Google Patents

Abstract

PURPOSE:To obtain a magnetic head which is suited for recording and reproducing of high frequency signals with improvement of mechanical strength, by providing a thin epoxy resin layer between a main body core and a reinforcing core and forming a resin sink linked to the epoxy resin layer of the reinforcing core. CONSTITUTION:Cores 10 and 30 are unified with epoxy resin, and a coupling part 40 having thin and thick parts is formed between both cores. The epoxy resin having its viscosity reduced by a diluent is coated with <=10mu thickness between the core 10 and cores 30 and 30 to apply the pressure between both cores 30. As a result, an adhesive layer 41 has >=2mu thickness after hardening. When the pressure is applied, the excessive resin produced between counter faces of cores 10 and 30 flows out to notched parts 34, a winding hole 13 and pierced holes 32 to form resin sinks 42 linked to the layer 41. The sufficient mechanical strength is not obtained between both cores by the layer 41 since the thickness of the layer 41 is small. However, the sinks 42 function to increase said mechanical strength. Furthermore the small thickness of the layer 41 gives no deterioration to improvement of the reproduction output characteristics due to the cores 30.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head suitable for recording and reproducing high frequency signals.

Conventional alloy magnetic materials have a large saturation magnetic flux density and are suitable as core materials for magnetic heads used in combination with magnetic tapes with high coercive force, such as metal tapes. It was thought that it would be best to obtain the expected reproduction output characteristics by using a thin current tank for those containing the following. Thin enough to be unaffected by the current bath that thins the core [for example, 30. This is because if the magnetic field is set to s or less), the magnetic resistance in the rear magnetic path increases, and the reproduction output decreases accordingly. Therefore, the present inventors placed reinforcing bodies on both sides of the thin main body core to compensate for mechanical strength, and made the part of this reinforcing body corresponding to the rear magnetic path with a ferromagnetic material such as ferrite. A magnetic head has already been developed in which the magnetic resistance in the rear magnetic path is reduced by increasing the magnetic field to 4% l, thereby exhibiting reproduction output characteristics suitable for practical use. FIG. 1 shows a perspective view of the structure.

In the figure, P) is a main body core made of alloy magnetic material (for example, sendust, amorphous base metal, etc.) θ1 et al., +Ql is a reinforcing core with substantially the same configuration that sandwiches this main body core from both sides. Front gap) facing ゛T
A non-magnetic material (for example, glass) part (Ql) and a magnetic material (for example, ferrite) part (Q2) facing the rear magnetic path are provided. By the way, in this conventional example, the main body core [P
In order to reduce the magnetic resistance by bonding the reinforcing core tQI as closely as possible, we used an anoethyl acrylate resin (commonly known as
Instant adhesive (glue) is infiltrated between both cores to bond them.

By utilizing the low viscosity of this resin (1 to 2 (lp8)), it is possible to obtain a relatively thin adhesive layer (less than a few doors).
Even so, there are some areas where the resin does not reach,
It has been found that if this unfinished portion were to face the tape contact surface, magnetic powder would penetrate into it, and the wedge effect of this penetrating magnetic powder would cause chipping in the main body core.

On the other hand, attempts have been made to interpose an r-boxy resin layer between both cores to bond and integrate them, but the layer thickness must be made sufficiently small (for example, 1
If the layer thickness is increased (for example, 10 or more) to obtain the necessary strength, the effect of reducing magnetic resistance cannot be fully brought out.A
Being tolerated.

Note that Evokin resin generally has high viscosity (30Qp81j
J, above), it is difficult to fill between both cores using the infiltration method.In this case, filling is done by disposing this resin between the oriented cores and applying pressure to spread it, but in this case, the resin is filled from between the two cores. Even if the main body core is surrounded by the bathed resin, sufficient mechanical strength cannot be obtained because the total thickness of the main body core is extremely thin, that is, the attachment M@ of the resin to the main body core f2 is small.

Problem of the Invention It is an object of the invention to provide a magnetic head suitable for recording and reproducing high-frequency signals such as TV signals on a high-resistance catheter, which improves both its mechanical and magnetic properties. It is something.

Key Points of the Invention A thin layer of evoquin resin (for example, 2 tones or less) is interposed between the main body core made of an alloy magnetic material and the reinforcing core to which it is attached, and the magnetic resistance is increased based on this resin layer. In addition to preventing deterioration of playback output characteristics, the reinforcing core prevents resin accumulation (
This is intended to ensure the bonding strength between the two cores and, in turn, the mechanical strength of the magnetic head.

Embodiment of the invention FIG. 2 is a perspective view of the configuration of one embodiment of the invention, and FIG.
FIG. 4 is a cross-sectional view taken along line 1-1 in FIG. 2, and FIG. , No. 5- is an exploded perspective view showing processing 11 of the tape contact surfaces of the main body core and the reinforcing core and before joining.

A magnetic head ([) is a main body core opening O] made of an alloy magnetic material such as Sendust (or amorphous alloy).

A set of reinforcing cores (30
) and a coil (1 shown and 1 omitted), and this magnetic head has extremely small external dimensions (the height and [() are approximately 2
．． 8, and the thickness is about 230 mm, so when it is fixed to the head base (not shown), for example, V 'I'h's /
A rotary disk or a rotating disk (which can be used in two different ways).

The main body core opening α is lf with the core half ulJoz together.
At least one of the core halves has a front gap U41 on the opposite side and a back gap +151 on the lower side.5th
Broken line q in the figure ((1 is used to define the depth 0 on the tape contact surface that will be used when processing the tape contact surface in the future.Both core halves) (12 is the abutment between the two The C is integrated by the bonding material (wax wax) placed in plural spots between the surfaces.The total thickness of this main body core (19
corresponds to the 11 tracks of the magnetic head (selected by the officer, but is limited by the number of recording/reproducing signal frequencies, thin current loss, etc.), and is limited to about 26 in this embodiment.

The reinforcing core group is equipped with a non-6H magnetic body 6v arranged in two pairs with a front gap of 0, a through hole facing the first winding hole 031, and a magnetic part (to), and a frontage in the periphery. The reinforcing core has a plurality of cutouts (six in the example) with a depth of about 250/''.The thickness fj of this reinforcing core is mainly limited by the size of the slit for protruding the head of the VTR cylinder. Therefore, in this embodiment, the city J1007 is selected as -C.

The non-magnetic part 6υ is made of a lath material which has a higher abrasion resistance against the running tape than Sendust, which is the material of the main body core, while the magnetic part ω is made of ferrite which has a higher specific resistance than Sendust. Ru. The two may be joined by interposing a suitable bonding material, but in this embodiment, the above-mentioned glass material is fused. - These two cores are integrated with epoxy resin, and there is a joint part (g) between the two cores that has a thin part and a thick part.
form. Next, in C2, this joint will be explained.

Between the main core +1 (l) and the reinforcing core c, B, use a diluent to lower the viscosity (for example, if the viscosity at the curing temperature is 1, Q O
The L-boxy resin having a coating thickness of 10.0 mm or less) is placed so that the average coating thickness is 10. Make sure that 14D is 2 voices or less. When applying this pressure, both cores tlU
The excess resin between IFIJi1 and IFIJi1 of I C1 (11) overflows into the notch (A and winding hole 031. Since the thickness of the adhesive layer D is small, the mechanical strength of this adhesive layer on both cores is not sufficient as described above. However, the resin 1 (f: Since a thick layer (more than 10 units) is installed between the inner wall surface and the main body core surface exposed by this notch, this resin pool acts to sufficiently increase the mechanical strength between the two cores (IOl (301)). Separately from this embodiment, a needle through hole frill (see Fig. 3) facing the notch (2) is provided in the main body core 00), and the resin reservoirs of one set of reinforcing cores are connected through this through hole. Also, the notches should not be provided on the four sides of the magnetic material part as shown in the figure, but only on the two sides on the left and right.
A resin may be added therein.

Effects of the Invention Since the adhesive layer between the main body core and the reinforcing core is thinned, the effect of improving the reproduction output characteristics by the reinforcing core is not impaired, and a resin reservoir is provided in the notch of the reinforcing core. The mechanical strength can be increased because the thickness of the resin at the part is set to a size that allows sufficient bonding strength.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the configuration of a conventional magnetic head; Fig. 2-
FIG. 4 shows one embodiment of the present invention, FIG. 2 is a perspective view of the structure, and FIG. 3 is a sectional view taken along line I-I [1] in FIG. 2. be. Fig. 5 is an exploded perspective view of an intermediate product of the magnetic head of the present invention. Explanation of main figure numbers 0I... Main body core, ■... Reinforcement core, [Yes].
...Notch decoy...Joining part, 14D...Thin wall part,
02...Thick interior 53-

Claims (1)

[Claims] tl+ A main body core made of a metal magnetic material having a front gap extending from the tape contact surface toward the winding hole, and a side surface (two pairs) of the H main body core adjacent to the tape contact surface. a reinforcing core arranged between the two cores and having a non-magnetic part with a tension of 1 mT relative to the front gap, an elbow through hole facing the winding hole, and a magnetic part; and a reinforcing core arranged between the two cores and integrating the two cores. The magnetic head is characterized in that the joint portion includes a thin portion disposed between opposing surfaces of the two cores and a thick interior portion disposed between adjacent surfaces of the two cores. (21) The reinforcing core is characterized in that a plurality of notches are provided in the outer/i!i1 part, and a thick inner part that is carried to the thin part is provided in the notches. Claim No. (
1) The magnetic head described in item 1). (3) The bonded portion has a viscosity of 100p8 during hardening treatment.
A magnetic head according to claim 11, characterized in that it is made of the following epoxy resin. 7