JPS5992415A - Magnetic head - Google Patents

Abstract

PURPOSE:To prevent tape squeak and at the same time to improve the environmental stability for a magnetic head by using a resin containing an organic lubricant to fix only the area near a magnetic gap at the side of the sliding surface of a magnetic recording medium of a magnetic core which is loaded into a shielding case. CONSTITUTION:Magnetic core halves 3 and 3 supported by a core support 2 are stored within a shielding case 1. These core halves are butted to each other via a magnetic gap 4, and the side of the gap 4 is turned to an opening part 1a formed at the sliding surface side of a magnetic recording medium 5 of the case 1. Then the area at the sliding surface side of the magnetic recording medium of the magnetic core and near the gap 4 is fixed with resin 7 containing an organic lubricant. While other aeas are fixed with resin 6 containing no organic lubricant. The resin of a fixing material uses the thermosetting resin like rubber, spoxy, urethane, unsaturated polyester resin, etc. While the organic lubricant contains all organic materials which are recognized as lubricants in various fields and in a solid, liquid or semi-solid state.

Description

TECHNICAL FIELD The present invention relates to a magnetic head, and more particularly to a magnetic head having a structure in which a magnetic core, a core support, and a magnetic core are housed in a shield case and fixed with resin.

Prior Art The structure of a conventional magnetic head of this type is shown in FIGS. 1 and 2.

In FIGS. 1 and 2, reference numeral 1 denotes a shield case, and inside this shield case 1, a magnetic core half-hole 3.3 is accommodated while being supported by a core support 2.

The magnetic core halves 3.3 are butted against each other through a magnetic gap 4, and the resin is placed with the magnetic gap 4 side facing the opening 】a formed on the sliding surface side of the magnetic recording medium 5 of the shield case 1. 6 is filled and fixed integrally.

An example of a resin used as this fixing material is as follows: 40 g of epoxy resin, 16 g of aromatic amine curing agent and 1 g of additive are added to CaC03 (heavy filler 6 (1)) and mixed thoroughly. It is used after stirring.

With this structure, when a magnetic recording medium is run and brought into contact with a magnetic head for recording and reproduction, frictional resistance increases due to magnetic pressure due to the frictional heat or static electricity generated during the running, and the magnetic recording medium and resin 6 and delicate close contact,
By repeating peeling, the dynamic friction between the magnetic head and the magnetic recording medium changes. This results in a magnetic core with a magnetic cap.

The closed magnetic path formed by the magnetic recording medium changes, and electromagnetic noise is generated during recording and reproduction.

When such a phenomenon occurs to magnetic tape.

The sliding sound can now be heard directly. This is a phenomenon called tape squeal.

When a resin like the one described above is used as a fixing material (this tape squeal phenomenon cannot be avoided).

Therefore, in order to prevent this tape squealing phenomenon, a structure has been proposed that significantly reduces the tape squealing phenomenon by using a resin 7 containing an organic lubricant added to the resin as a fixing material, as shown in Figure 3. has been done.

That is, the resin used as the fixing material is, for example, a com type resin.

Thermosetting resins such as epoxy, urethane, and unsaturated polyester resins are used, and examples of hardening agents include polyamides,
Amine-based, acid anhydride-based, imidazole-based, etc. are used.

In addition, the organic lubricant contains all the solid substances recognized as lubricants in various fields, and is in solid form.

The lubricant may be either liquid or semi-solid.

In addition, these organic lubricants may be classified from the viewpoint of raw materials: petroleum-based, synthetic-based, or fatty oil-based.

Among these organic lubricants, those that can be preferably used can be roughly divided into metal soaps, fatty acid esters, shoulder strap alcohols, and amines.

Silicone oils, fatty acid amides, olefin polymers, polyalkylene glycols, halogenated hydrocarbon oils, various petroleum-based lubricants or mixed lubricants, and lubricating oils mixed with specified thickening agents. I can list many things.

Incidentally, in addition to the above-mentioned organic lubricant, an inorganic fine powder can be added at the same time, thereby increasing the effect of reducing tape squeal. An example is Al2O3.

CaCO3, Cr2O3, 5L02, α-Fb20
3, Cu, Mo, W, Cr.

A/! There are also graphite, talc, fluorocarbon, etc.

MoS2, boron nitride, etc. are also preferred.

In the case of an organic lubricant, the appropriate amount of these additives is 0° to 30% by weight, and in the case of an inorganic fine powder, the appropriate amount is 10 to 80% by weight.

However, among these, especially when a liquid specific lubricant is added, the function of the resin as a fixing material may be weakened. That is, since the adhesive strength depends on the curing reaction of the resin, a liquid organic lubricant that does not take part in the curing process weakens the adhesive strength. Furthermore, after curing, the liquid substance is dispersed and dissolved in the solid, which may increase the coefficient of linear expansion.

As described above, due to a decrease in adhesive strength, an increase in the coefficient of linear expansion, and a decrease in heat resistance, it becomes difficult to maintain the magnetic recording, reproducing, and erasing characteristics of the magnetic head, such as resistance to high temperatures, high humidity, and thermal shock. There is a risk that this may occur.

Therefore, examples of fixing materials that do not contain liquid organic lubricants are as follows. In other words, an example of a resin used as a fixing material is epoxy resin "+';'I" as mentioned above.
To 40 g of fat and 36 g of CaCO, 16.7 g of an aromatic amine curing agent and 1 g of an additive are added and thoroughly mixed and stirred. On the other hand, in order to provide an effect of preventing tape squeal, an organic lubricant is added to the epoxy resin in an amount of about 0.1 to 30% by weight. Q: What are some specific examples of organic lubricants?

Metal salts of higher fatty acids such as steering acid and palmitic acid (Na, Ca, Mg, Ba, Li, Al, Zn, F
g, Cu-.

So-called metal soap C (Pb, Sn salt, etc.)
I(-COO)nM], higher alcohols such as ethyl oleate and ethyl nutearate [)L-OH'), and t-butylamine.

Amines [R-NH2) such as amylpropionic acid and cyclohexamine nitrite, methylpolysiloxane.

Silicone oils such as phenylmethyl silicone compounds and methyl silicone compounds, and oleic acid amide.

Fatty acid amides such as stearinamide [R-CONI (
2) − etc.

Adding one or more of these organic lubricants (
・Can provide tape squeal prevention effect.

In addition, other examples of fixing materials having tape squeal prevention effects include epoxy resin 409, which is similar to the one mentioned above.
CaC03b O9, aromatic amine curing agent] The same effect can be obtained by adding 5q of an organic lubricant containing 50% each of ethyl oleate and Ca atearate to 6C and additive 19, and mixing and stirring. The effect of this can be obtained.

However, even with the use of a fixing material that has the effect of preventing tape squeal, it has been found that it is difficult to maintain the reproduction, recording, and erasing characteristics of the completed magnetic head before and after environmental resistance tests.

Purpose The present invention has been accomplished in order to eliminate the above-mentioned drawbacks of the conventional technology, and provides stable recording, playback, and erasing characteristics without large fluctuations in environmentally accelerated tests such as heat resistance, moisture resistance, and thermal shock resistance. The purpose of the present invention is to provide a magnetic head that exhibits the following characteristics.

The present invention aims to achieve the above objectives.

A structure was adopted in which only the vicinity of the magnetic gap on the side of the magnetic recording medium oil moving surface of the magnetic core was fixed with a resin containing an organic lubricant.

The present invention will be described in detail below based on an embodiment shown in one drawing.

Figure 4 is for explaining one embodiment of the present invention.
Components that are the same as those in FIGS.

The explanation will be omitted.

In the original embodiment, as is clear from FIG. 4, the magnetic recording sliding surface side of the magnetic core and the vicinity of the magnetic gap are fixed with resin 7 containing an organic lubricant.

The other parts are fixed with a resin 6 that does not contain an organic lubricant.

This is how to fix the magnetic core.

The following methods can be considered.

(1) With the magnetic recording sliding surface side of the magnetic head facing down, resin 7 containing an organic lubricant as a fixing material is first poured and hardened near the magnetic gap, and then a resin 7 containing an organic lubricant is poured into the magnetic head. A method of fixing by pouring resin 6 as a fixing material.

(2) With the magnetic recording medium finger side facing up, resin 6 that does not contain an organic lubricant is poured from the opening 1a side and cured, and then resin 7 containing an organic lubricant is poured and cured. Method.

(3) Magnetic recording sliding surface side down? A method of impregnating a stationary phase containing an organic lubricant through the opening]a, and then pouring a fixing material containing no organic lubricant from the opening at the rear end of the shield cane J and curing it.

Several methods can be considered as described above, but in any case, the resin 7 containing an organic lubricant is used on the sliding surface side of the magnetic recording medium.
．． It is filled with.

In this way, if a fixing material containing an organic lubricant that has an effect of preventing tape squeal is used only on the magnetic recording sliding surface side, the role of the tape squeal preventing effect will be completely diminished, and the other parts will be The environmental stability of the fixing material containing an organic lubricant can be significantly reduced.

Therefore, it is sufficient to fill the parts other than the resin 7 containing organic lubricants with resin 6 that does not contain these.

An environmental test was conducted to compare the magnetic head having the structure shown in FIG. 4 with other conventional magnetic heads.

First, there is a magnetic head having a magnetic core fixed with a resin 6 containing no organic lubricant as shown in FIGS. 1 and 2, and a magnetic head fixed with a resin 7 containing an organic lubricant as shown in FIG. 20 fixed magnetic heads and 20 magnetic heads according to the present invention as shown in FIG. 4 were prepared. Then, a thermal shock test was selected as the environmental test condition, and changes in reproduction frequency characteristics before and after the test were investigated.

The thermal shock test was carried out at -40'C to +80° as shown in Figure 5.
Eight cycles were carried out in which the temperature was maintained at 65% C for 2 hours each.

A 4-channel cassette playback head was used as the magnetic head, and measurements were made using a normal position tape.

The results of this thermal shock test are shown in Table 1.

In Table 1, ±3σ indicates variation.

As is clear from Table 1, it was found that the magnetic head according to the present invention had good changes and variations in reproduction frequency characteristics and was excellent in environmental stability.

Effects As is clear from the above explanation, according to the present invention, the magnetic core installed in the shield case is fixed near the magnetic gap on the side of the magnetic recording medium sliding direction of the magnetic core with a resin containing an organic lubricant. Since the other parts are filled with resin that does not contain organic lubricants, a magnetic head that not only prevents tape squeal but also has excellent environmental stability can be obtained.

[Brief explanation of the drawing]

1 and 2 are a front view and a cross-sectional plan view explaining a conventional structure, FIG. 3 is a cross-sectional plan view showing another example of a conventional structure, and FIG. 4 is a cross-sectional plan view explaining an embodiment of the present invention. Plan view,
Figure 5 is an explanatory diagram showing the environmental test method. 1... Shield case la-opening 3... Magnetic core half 4... Magnetic gap 5... Magnetic recording medium 6... Resin not containing organic lubricant 7... Organic lubrication resin containing agent

Claims (1)

[Claims] The magnetic core is installed inside the shield case, and the magnetic core is fixed with a fixing material mainly made of resin, with the magnetic gap part of the magnetic core facing the opening formed on the magnetic recording medium sliding surface side of the shield case. 1. A magnetic head, characterized in that the vicinity of the magnetic gap is fixed using a resin containing an organic lubricant, and the other parts are filled with a resin that does not contain the Arishimori lubricant.