JPH01217711A - Magnetic head - Google Patents

Abstract

PURPOSE:To improve the wear resistance of a magnetic core and to lower the cost of the title device by forming the track width directional dimension and the magnetic recording medium sliding directional dimension of one magnetic core half body larger than that of the other magnetic core half body and giving the former magnetic core half body the function of a dummy core. CONSTITUTION:One magnetic core half body 1 is formed into a rectangular flat thick plate shape, and a groove 1c for forming a magnetic gap 5 is formed on the body 1. The other magnetic core half body 2 is formed into an approximately U-shaped square bar shape, and one side part 2a of its U-shape is formed longer than the other side part 2b. Further, the magnetic core half body 1 to expose to a medium to a medium sliding surface 7 is formed widely larger in both the track width direction (vertical direction) of the magnetic gap 5 and an (a) direction of a medium sliding direction than the other magnetic core half body 2. Consequently, the larger magnetic core half body 1 performs the same function as that of the dummy core, and the intermediate part of the magnetic core half body 1 according to the effective track width of the magnetic gap 5 and its neighboring parts on both sides never receive strong sliding force locally and are hardly abraded. Thus, the wear resistance of the magnetic core can be improved, and the cost of the device can be lowered.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic head for magnetically recording or reproducing information on a magnetic recording medium, and particularly relates to a magnetic head formed by joining a pair of magnetic core halves through a magnetic gap. The present invention relates to a magnetic head that magnetically records and reproduces information by sliding a core on a magnetic recording medium.

[Prior Art] Conventionally, magnetic heads for magnetic card readers, which require particularly high abrasion resistance in this type of magnetic head, have used Sendust, which has a high hardness, as the material of the magnetic core in order to improve the abrasion resistance. Furthermore, in order to prevent uneven wear of the magnetic core, a structure is adopted in which a so-called dummy core, a block made of Sendust, which is the same material as the magnetic core, is provided on the sliding surface of the magnetic recording medium.

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. 5 shows the structure of the magnetic head shown in FIG. 4. It shows the magnetic core incorporated into the head. However, the magnetic core in FIG. 5 is shown before being assembled, and after being assembled, the magnetic recording sliding portion has not been subjected to cylindrical grinding.

In both figures, the reference numerals 1.2 indicate magnetic core halves, which are formed from Sendust into a U-shape in this case, and are butted and joined through a magnetic gap 5 to form the magnetic core. A non-magnetic gap spacer (not shown) is inserted into the magnetic gap 5 . Also both core halves 1.2
A coil bobbin 3 having a coil 3a wound thereon is fitted into the magnetic core through a hole 3b formed in the bobbin when the two core halves 1.2 are joined. The magnetic core fitted with the coil bobbin 3 is fitted and fixed in the case 4 together with other magnetic head constituent members (not shown). The tip of the magnetic core provided with the magnetic gap 5 is exposed to a medium sliding surface 7 that slides on a magnetic recording medium (not shown) of the magnetic head, and the tip surface is ground into a cylindrical shape together with the medium sliding surface 7. . Furthermore, the fourth
In the figure, reference numeral 8 denotes a connection terminal to which the end of the coil wound around the coil bobbin 3 is connected.

In addition to this structure, a dummy core designated by reference numeral 6.6 is provided on the sliding surface 7 in order to prevent uneven wear of the magnetic core consisting of the magnetic core halves 1.2 and improve the wear resistance of the magnetic head. . The dummy core 6.6 is made of Sendust, which is the same material as the magnetic core half 1.2, and is formed into a block shape, buried so as to be exposed in the medium sliding surface 7, and ground into a cylindrical shape together with the medium sliding surface 7. . The dummy cores 6.6 are provided adjacent to the magnetic core on both sides in the track width direction (vertical direction in FIG. 4).

The dummy core 6.6 is slid together with the magnetic core half 1.2 on a magnetic recording medium (not shown) that slides in the vertical direction in FIG. 4 when the magnetic recording medium slides. Since it is made of the same material as 1.2 and has the same wear resistance, uneven wear of both ends of the magnetic core half 1.2 in the track width direction is prevented.

[Problems to be Solved by the Invention] However, the conventional structure described above has the disadvantage that the provision of a dummy core increases the manufacturing cost in the head manufacturing process due to the following points.

That is, first, it is necessary to cut out two dummy cores for each magnetic head from sendust, which is difficult to work with, and shape them separately from the magnetic core halves.

In addition, in order to provide a dummy core, the medium sliding surface of the main body of the magnetic head is subjected to cylindrical grinding, the portion of the medium sliding surface where the dummy core is installed is ground, the dummy core is glued to the same portion, and then the medium sliding surface is re-grinded. cylindrical grinding, etc., resulting in a significant increase in man-hours.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a magnetic head that can be manufactured at low cost using a small number of parts and a simple process, and 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 through a magnetic gap is slid onto a magnetic recording medium to record information. In a magnetic head that performs magnetic recording or reproduction, the dimension in the track width direction of the magnetic recording medium sliding portion of one magnetic core half and the dimension in the magnetic recording medium sliding direction are calculated as follows: A structure is adopted in which the one half of the magnetic core doubles as a dummy core to prevent uneven wear of the magnetic core.

[Function] According to such a structure, uneven wear of the magnetic core is prevented through one half of the magnetic core which also serves as a dummy core, and the wear resistance of the magnetic head is improved. Furthermore, since the magnetic core halves also serve as dummy cores, the number of components of the magnetic head is reduced, the manufacturing process is simplified, and costs can be reduced.

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

1 to 3 illustrate the structure of a magnetic head for a magnetic card reader according to an embodiment of the present invention. FIG. 1 shows the appearance of the entire magnetic head, and FIGS. They are an exploded perspective view and an assembled perspective view showing the structure of a magnetic core and a coil bobbin, respectively. However, the magnetic core shown in FIGS. 2 and 3 is before being assembled into the magnetic head main body, and the sliding portion has not been subjected to finishing grinding. In these figures, parts common or corresponding to those in FIGS. 4 and 5 of the conventional example described above are given the same reference numerals, and explanations 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 1.2 constituting the magnetic core are made of a magnetic material with excellent wear resistance, such as Sendust, as in the conventional example. However, its shape and structure differ from the conventional example as follows.

That is, first, one magnetic core half 1 is formed into 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 front right side in the figure. A groove IC is formed for this purpose. The protruding portion of the groove 10 on the upper side in the figure will later be used as a half of the magnetic core during the grinding process of the medium sliding surface 7 of the magnetic head! When the upper surface side in FIG. 2 is ground into a cylindrical shape, it is removed at the same time.

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

The magnetic core halves 1.2 are then assembled as shown in FIG. That is, one side portion 2b of the magnetic core half 2
A coil pobbin 3 with a coil 3a wound thereon is fitted through the hole 3b, and the other magnetic core half 1 is placed on the side portion 2b.
are overlapped, and the magnetic core half 1 is connected to the other side portion 2a of the magnetic core half 2 via the groove 1c for forming a magnetic gap.
are butted and joined.

The assembly of the magnetic core and coil bobbin 3 made up of the magnetic core halves 1.2 thus joined is fitted and fixed in the case 4 of the magnetic head shown in FIG. 1. li1! The tips of the magnetic core half 1 and the side portion 2a of the magnetic core half 2 are exposed to 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 10 portion of the magnetic core half 1.

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

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

According to the structure of the magnetic head of this embodiment, by setting the dimensional relationship of the medium sliding portion exposed to the medium sliding surface 7 of the magnetic core half 1.2 as described above, a large The other magnetic core half 1 performs the same function as the dummy core of the conventional example described above, and the magnetic core half 1 also serves as a dummy core.

That is, a magnetic recording medium (not shown) moves on the medium sliding surface 7 in the first direction.
By sliding in the direction a in the figure and sliding the medium sliding part of the magnetic core half 1°2, the magnetic core half 1 is moved out of the effective track width of the magnetic gap 5 when viewed in the track width direction. Even if both ends la and lb wear unevenly, the inner part, that is, the middle part corresponding to the effective track width of the magnetic gap 5 and the parts near both sides thereof, are locally strengthened by the existence of both ends la and lb. Since it is not subjected to sliding force, it is less prone to wear and uneven wear is prevented. Similarly, the tip of the magnetic core 12 facing the intermediate portion of the magnetic core half 1 through the magnetic gap 5 is also a magnetic core half! The presence of both ends 1a and 1b protects the material from wear and prevents uneven wear.

In this way, according to this embodiment, one magnetic core half 1 also serves as a dummy core, so that the middle part of the magnetic core half 1 and the other magnetic core half 2 can be biased according to the effective track width of the magnetic gap 5 of the magnetic core half 1. Wear is prevented and the wear resistance of the magnetic core can be improved.

Further, according to this embodiment, since the magnetic core half 1 also serves as a dummy core, a conventional independent dummy core is not used, and the number of parts is reduced accordingly. The process for providing the head can be omitted, the manufacturing process is greatly simplified, and costs can be significantly reduced.

[Effects of the Invention] As is clear from the above description, according to the present invention, a magnetic core formed by joining a pair of magnetic core halves through a magnetic gap is slid onto a magnetic recording medium to magnetically record information. Or, in a magnetic head that performs reproduction, the dimensions of the magnetic recording medium sliding part of one magnetic core half in the track width direction and the dimensions in the sliding direction of the magnetic recording medium are larger than those of the other magnetic core half. Since we have adopted a structure in which one of the magnetic core halves doubles as a dummy core to prevent uneven wear of the magnetic core, uneven wear of the portion corresponding to the effective track width of the magnetic gap of the magnetic core is prevented. It is possible to improve the wear resistance of the magnetic core by preventing this, and it also has the excellent effect of reducing the number of parts and greatly simplifying the manufacturing process, resulting in a significant cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the overall appearance of a magnetic head according to an embodiment of the present invention, 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.
Figure 3 is a perspective view of the assembled magnetic core and coil bobbin, Figure 4 is a perspective view showing the overall appearance of the conventional magnetic head, and Figure 5 is the structure of the magnetic core and coil bobbin incorporated into the conventional head. FIG. 1.2...Magnetic core half 3...Coil bobbin 4.
...Case, 5...Magnetic gap 7...
・Medium sliding surface 8... Connection terminal tH, 4, y-
Figure 1 2 Maki Hefu Ryo's beginnings Heh, F's Drunken Sakaki Chronicles Part 4

Claims (1)

[Claims] 1) In a magnetic head that magnetically records or reproduces information by sliding a magnetic core formed by joining a pair of magnetic core halves onto a magnetic recording medium, the magnetic recording medium of one magnetic core half The dimensions of the sliding portion in the track width direction and the dimension in the sliding direction of the magnetic recording medium are formed to be significantly larger than the medium sliding portion of the other magnetic core half. A magnetic head characterized by serving as a dummy core to prevent wear.