JP2527455B2 - Magnetic head - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a magnetic head for magnetically recording or reproducing information on a magnetic recording medium, and more particularly to a magnetic head formed by joining a pair of magnetic core halves via a magnetic gap. The present invention relates to a magnetic head that performs magnetic recording / reproduction of information by sliding a core on a magnetic recording medium.

[Prior Art] Conventionally, in a magnetic head for a magnetic card reader which is required to have particularly high wear resistance in this type of magnetic head, a high hardness sendust is used as a material of a magnetic core in order to improve wear resistance. Further, in order to prevent uneven wear of the magnetic core, a structure in which a block called a dummy core made of sendust of the same material as the magnetic core is provided on the sliding surface of the magnetic recording medium is adopted.

FIGS. 4 and 5 explain the structure of a conventional magnetic head provided with such a dummy core. FIG. 4 shows the overall appearance of the magnetic head, and FIG. The magnetic core incorporated in the head is shown. However, the magnetic core in FIG. 5 shows a state before the assembling and after the assembling, the magnetic recording sliding portion is not subjected to the cylindrical grinding.

In both figures, reference numerals 1 and 2 respectively denote magnetic core halves, which are formed from sendust in this case in a U-shape, and are abutted and joined via a magnetic gap 5 to form a magnetic core. A non-magnetic gap spacer (not shown) is bitten by the magnetic gap 5. Also, a coil bobbin 3 in which a coil 3a is wound around a magnetic core composed of both core halves 1 and 2.
Are fitted at the time of joining both core halves 1 and 2 through a hole 3b formed in the bobbin. The magnetic core fitted with the coil bobbin 3 is fitted and fixed to the case 4 together with other magnetic head constituent members (not shown). The tip portion of the magnetic core provided with the magnetic gap 5 is exposed to the medium sliding surface 7 of the magnetic head which slides on a magnetic recording medium (not shown), and the tip surface is ground into a cylindrical shape together with the medium sliding surface 7. . In FIG. 4, reference numeral 8 is a connection terminal to which the coil terminal wound around the coil bobbin 3 is connected.

In addition to such a structure, dummy cores 6 and 6 are provided on the sliding surface 7 in order to prevent uneven wear of the magnetic core composed of the magnetic core halves 1 and 2 and improve wear resistance of the magnetic head. . The dummy cores 6, 6 are formed in a block shape from sendust, which is the same material as the magnetic core halves 1, 2, are embedded so as to be exposed on the medium sliding surface 7, and are ground together with the medium sliding surface 7 into a cylindrical shape. The dummy cores 6, 6 are provided adjacent to both sides of the magnetic core in the track width direction (vertical direction in FIG. 4).

The dummy cores 6, 6 are slid together with the magnetic core halves 1, 2 on a magnetic recording medium (not shown) that slides in the direction of arrow a in FIG. 4 when the magnetic recording medium slides. The same material as the bodies 1 and 2 and the same wear resistance prevents uneven wear of both ends of the magnetic core halves 1 and 2 in the track width direction.

[Problems to be Solved by the Invention] However, in the above-described conventional structure, since the dummy core is provided, the manufacturing cost of the head is extremely high from the following points.

That is, first, it is necessary to separately form two dummy cores for each magnetic head from sendust, which has poor workability, separately from the magnetic core half body.

Also, to provide a dummy core, the main body of the magnetic head is once subjected to cylindrical grinding on the medium sliding surface, then the dummy core installation part on the medium sliding surface is shaved, the dummy core is bonded to the same part, and then the medium sliding surface is re-attached. The number of man-hours will be significantly increased due to the cylindrical grinding.

Therefore, an object of the present invention is to provide a magnetic head which can be manufactured inexpensively with a small number of parts and a simple process, and which has excellent wear resistance.

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a magnetic core formed by joining a pair of magnetic core halves via a magnetic gap is slid on a magnetic recording medium to transfer information. In a magnetic head for magnetic recording or reproduction, the dimension in the track width direction of the magnetic recording medium sliding portion of one magnetic core half body and the dimension in the magnetic recording medium sliding direction are set to the medium sliding portion of the other magnetic core half body. A structure is adopted in which the magnetic core half body is formed to be much larger, and the one magnetic core half also functions as a dummy core for preventing uneven wear of the magnetic core.

[Operation] With such a structure, uneven wear of the magnetic core is prevented through the one magnetic core half that also serves as the dummy core, and the wear resistance of the magnetic head is improved. Further, since the magnetic core half serves also as the dummy core, the number of parts of the magnetic head is reduced, the manufacturing process is simplified and the cost is reduced.

[Examples] Hereinafter, details of examples of the present invention will be described with reference to the drawings.

1 to 3 are diagrams for explaining the structure of a magnetic head for a magnetic card reader according to an embodiment of the present invention.
The figure shows the appearance of the entire magnetic head, and FIGS. 2 and 3 are an exploded perspective view and a perspective view of the assembled state showing the structures of the magnetic core and the coil bobbin, respectively. However, the magnetic core shown in FIGS. 2 and 3 is in a state before being incorporated into the magnetic head main body and has not been subjected to finish grinding of the sliding portion. In these figures, the parts common or corresponding to those in FIGS. 4 and 5 of the above-mentioned conventional example are designated by the same reference numerals, and the description of the common parts will be omitted.

In the structure of the head of this embodiment shown in FIGS. 1 to 3, the magnetic core halves 1 and 2 constituting the magnetic core are made of a magnetic material having excellent wear resistance as in the conventional example, such as sendust. Although it is formed, the shape structure is different from the conventional example as follows.

That is, first, one magnetic core half body 1 is formed in a rectangular flat thick plate shape as shown in FIG. 2, and the magnetic gap 5 in FIG. 1 is formed on the end face on the right front side in the drawing. A groove 1c for forming is formed. The traveled portion on the upper side of the groove 1c in the figure is removed at the same time when the upper surface side of the magnetic core half body 1 in FIG. 2 is ground later in the grinding of the medium sliding surface 7 of the magnetic head.

Next, the other magnetic core half 2 is formed into a substantially U-shaped rectangular rod shape, and one side portion 2a of the U-shape is the other side portion.
It is formed longer than 2b.

The magnetic core halves 1 and 2 are then assembled as shown in FIG. That is, one side portion 2b of the magnetic core half body 2 is fitted with the coil bobbin 3 around which the coil 3a is wound through the hole 3b, and the other magnetic core half body 1 is further stacked on the side portion 2b. Groove for body 1 to form a magnetic gap
The other side portion 2a of the magnetic core half body 2 is butted and joined via 1c.

The assembly of the magnetic core consisting of the magnetic core halves 1 and 2 and the coil bobbin 3 thus joined together is fitted and fixed in the case 4 of the magnetic head shown in FIG. The front portion of the magnetic core half body 1 and the tips of the side portions 2a of the magnetic core half body 2 are exposed on the medium sliding surface 7 of the magnetic head and are ground into a cylindrical shape as a whole. A magnetic gap 5 is formed through the groove 1c portion of the magnetic core half body 1.

As shown in FIG. 1, the dimensions of the front portion of the magnetic core half 1 and the tip of the magnetic core half 2 exposed on the medium sliding surface 7 are the track width direction of the magnetic gap 5 (vertical direction in the figure). As for the magnetic core half body 1, the magnetic core half body 1 is formed to be significantly larger than the other magnetic core half body 2 in the a direction of the medium sliding direction.

The structure of the magnetic head of this embodiment other than the above is the same as that of the conventional example described above, and the description thereof is omitted.

According to the structure of the magnetic head of the present embodiment as described above, the dimensional relationship of the medium sliding portion exposed on the medium sliding surface 7 of the magnetic core halves 1 and 2 is set large as described above. The magnetic core half body 1 has the same function as the above-described dummy core of the conventional example, and also serves as the dummy core of the magnetic core half body 1.

That is, a magnetic recording medium (not shown) slides on the medium sliding surface 7 in the direction a in FIG. 1 and slides on the medium sliding portions of the magnetic core halves 1 and 2, whereby the magnetic core half 1 For both the end portions 1a and 1b protruding from the effective track width of the magnetic gap 5 when viewed in the track width direction are worn due to unevenness, the inner portion, that is, the intermediate portion corresponding to the effective track width of the magnetic gap 5 is formed. The parts near both sides are both ends 1a, 1
Due to the presence of b, it does not locally receive a strong sliding force, is less likely to be worn, and uneven wear is prevented. The tip of the magnetic core 2 facing the intermediate portion of the magnetic core half 1 through the magnetic gap 5 is also guarded by the presence of both ends 1a and 1b of the magnetic core half 1 and is less likely to wear. Wear is prevented.

As described above, according to this embodiment, one magnetic core half 1 also serves as a dummy core, so that the magnetic core half 1 has an intermediate portion corresponding to the effective track width of the magnetic gap 5 and the other magnetic core half 2 is biased. Wear is prevented and the wear resistance of the magnetic core can be improved.

Further, according to the present embodiment, since the magnetic core half body 1 also serves as a dummy core, a conventional independent dummy core is not used. Therefore, the number of parts is reduced by that much, and the dummy core machining process and the magnetic core manufacturing process are performed in the magnetic head manufacturing process. The step of providing the head can be omitted, the manufacturing process can be greatly simplified, and the cost can be significantly reduced.

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, magnetic recording of information is performed by sliding a magnetic core formed by joining a pair of magnetic core halves with a magnetic gap on a magnetic recording medium. Alternatively, in the reproducing magnetic head, the dimension in the track width direction of the magnetic recording medium sliding portion of one magnetic core half body and the dimension in the magnetic recording medium sliding direction are made larger than those of the other magnetic core half body. The one half of the magnetic core has a structure that doubles as a dummy core to prevent uneven wear of the magnetic core.Therefore, uneven wear of the portion of the magnetic core corresponding to the effective track width of the magnetic gap is adopted. And the wear resistance of the magnetic core can be improved, and the number of parts can be reduced, the manufacturing process can be greatly simplified, and a significant cost reduction can be achieved.

[Brief description of drawings]

1 is a perspective view showing the overall appearance of a magnetic head according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view showing the structure of a magnetic core and a coil bobbin incorporated in the magnetic head of FIG.
FIG. 3 is a perspective view of the magnetic core and the coil bobbin assembled, FIG. 4 is a perspective view showing an overall appearance of a conventional magnetic head, and FIG. 5 is a structure of the magnetic core and the coil bobbin incorporated in the conventional head. FIG. 1,2 ...... magnetic core half, 3 ... coil bobbin 4 ... case, 5 ... magnetic gap 7 ... medium sliding surface, 8 ... connection terminal

Claims (1)

(57) [Claims] 1. A magnetic head for magnetically recording or reproducing information by sliding a magnetic core formed by joining a pair of magnetic core halves with a magnetic gap on a magnetic recording medium. The dimension in the track width direction of the sliding portion of the magnetic recording medium and the dimension in the sliding direction of the magnetic recording medium are made significantly larger than the medium sliding portion of the other magnetic core half, and one of the magnetic core halves is magnetic. A magnetic head characterized by also functioning as a dummy core for preventing uneven wear of the core.