JP2771815B2 - Magnetic head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, and more particularly to a magnetic head that performs magnetic recording or reproduction of information by sliding a magnetic core fitted with a coil bobbin on a magnetic recording medium. The present invention relates to a magnetic head in which a plurality of magnetic cores are arranged in parallel in a track width direction and a shielding plate for a magnetic shield is provided between the magnetic cores.

[Prior Art] FIGS. 3 (A) and 3 (B) illustrate a conventional method of manufacturing a magnetic head of this type. In the process of manufacturing a magnetic head, a process of assembling a magnetic core, a coil bobbin and a blocking plate is described. It is to explain.

In both figures, reference numerals 2 and 2 'denote magnetic core halves (hereinafter abbreviated as core halves) constituting a magnetic core, which are formed from a high-permeability magnetic material into a bent shape as shown in the figure.
Reference numerals 3 and 3 ′ denote core halves 2 and 2 ′ and a shielding plate described later, respectively.
It is a support that supports 7,7 '. Reference numeral 4 denotes a coil bobbin around which a coil winding 4a is wound and a hole 4 for fitting the coil bobbin 4 to the core halves 2, 2 'as shown in FIG.
b is formed. Reference numeral 5 denotes a shim made of a non-magnetic material as a spacer constituting the magnetic gap of the magnetic core.

Further, reference numerals 7, 7 'denote blocking plates for performing magnetic shielding between the magnetic cores. The blocking plates 7, 7 'are formed in a shape as shown in FIG. 4, and the core half shown in FIG.
The core halves 2, 2 'are formed in a shape that shields the entire core halves 2, 2', including the regions inside the respective concave portions 2a, 2a '. The sectional structure of the blocking plates 7, 7 'is as shown in FIG. 5, and the non-magnetic spacing plates 8, 7 are provided on both sides of the magnetic plate 9.
8 has a three-layer structure.

In the assembling process of these members, first, the core half 2 and the blocking plate 7 are alternately arranged and fixed at predetermined intervals in the track width direction of the core half 2 as shown in FIG. I do. Similarly, the core half 2 'and the blocking plate 7' are fixed to the support 3 '.

Next, the coil bobbin 4 is fitted to the rear end of the core halves 2, 2 '(the lower end in the middle of FIG. 3A), and the shim 5 is sandwiched between the front ends of the core halves 2, 2'. Assembly of the core half 2, the support 3, and the blocking plate 7 and the core half 2 ', the support 3',
The assembly of the blocking plate 7 'is butted and joined as shown by the arrow A in FIG. 3 (B). A pair of joined core halves
2, 2 'constitute a magnetic core, and a shim 5 forms a magnetic gap in this magnetic core.

The assembly of the magnetic core, supports 3, 3 ', coil bobbin 4, and blocking plates 7, 7' obtained in this way is fitted and fixed to a magnetic head case (not shown) to form a magnetic head. Is done.

[Problems to be Solved by the Invention] However, according to the conventional method of manufacturing a magnetic head as described above, the number of turns of the coil winding 4a is increased or the coil winding 4a is disconnected due to the design of the magnetic head. When the diameter of the coil winding 4a is increased for prevention, when the winding diameter of the coil winding 4a is increased, the coil bobbin 4 is moved by the blocking plate 7,
There is a problem in that a collision cannot be made due to hitting 7 '. In addition, there is a problem that it is difficult to reduce the size of the entire magnetic head in order to secure the space for the coil winding 4a so as to avoid contact with the blocking plates 7, 7 '.

Therefore, as a countermeasure against such a problem, as shown in FIG. 6, the non-magnetic spacing plates 8 and 8 are not provided on the rear end side near the coil bobbin 4 as a structure of the blocking plates 7 and 7 '. A single-layer structure of only the plate 9 is employed. As is clear from the comparison between FIG. 5 and FIG. 6, it can be seen that the use of the blocking plate 7 of FIG.

However, even when the blocking plate shown in FIG. 6 is used, there is a case where the coil bobbin does not hit the blocking plate at the time of abutting due to the positional displacement of the blocking plate or the core half.

Therefore, an object of the present invention is to reduce the size of a magnetic head in the above-described type of magnetic head while taking into account the magnetic shielding effect of the shielding plate as much as possible, and to improve the assemblability while satisfying the size reduction. It is to provide a configuration.

Means for Solving the Problems According to the present invention, there is provided a structure in which a plurality of magnetic core halves and a shield plate for magnetic shield are alternately arranged in a track width direction by a support member and supported. A coil bobbin is fitted into each of the magnetic core halves, and two sets of this structure are abutted and joined together, and a cutout portion is provided in a region near the coil bobbin of the blocking plate. In the magnetic head having a supplementary blocking plate in a shape to make up the portion, the blocking plate provided with the cutout portion is formed so that both sides of the magnetic plate are laminated with a nonmagnetic plate, and the supplementary blocking plate is provided. Is formed only by a magnetic plate, and the thickness thereof is smaller than the thickness of the blocking plate provided with the cutout portion.

[Operation] According to such a configuration, a coil bobbin is fitted to each magnetic core half of the above-mentioned structure, and two sets of the structures are butt-joined to each other. On the other hand, if a supplementary shield plate is fitted, it is possible to prevent the coil bobbin from hitting the shield plate when two sets of structures are abutted. In addition, the thickness of the supplementary blocking plate is thinner than that of the blocking plate provided with the notch, so that the space for the coil bobbin can be secured, the size of the magnetic head can be reduced, and two sets of the structures incorporating the coil bobbin are joined together. Even if a supplementary blocking plate is installed later, it is easy to arrange the supplementary blocking plate within the thickness of the blocking plate provided with the cutout portion, and the assemblability of the magnetic head can be improved. further,
The arrangement of the supplementary blocking plate can satisfy the magnetic shielding effect.

Example An example of the present invention will be described below in detail with reference to the drawings.

1 (A), 1 (B) and 2 illustrate an embodiment of a magnetic head according to the present invention, and FIGS. 1 (A) and 1 (B) illustrate a core described above in a magnetic head manufacturing process. FIG. 2 shows an assembling process of an assembly including a half body, a coil bobbin, a blocking plate and a support, and FIG. 2 shows a structure of the blocking plate. In these figures, the same reference numerals are given to the same members as those in FIGS. 3A and 3B and the following drawings for explaining the conventional method, and the description thereof will be omitted.

The conventional blocking plate was configured as a set of two sheets,
In this embodiment, as shown in FIGS. 1 (A) and 2,
It is assumed that the blocking plates 1, 1 ', and 6, which are different from the conventional one, are used as one set.

First, a cut-off plate denoted by reference numerals 1 and 1 'is a main cut-off plate, which is a notch in which a rear inner portion near the coil bobbin 4 is cut away from an outer shape for shielding the entire core halves 2 and 2'. It is formed in a shape having portions 1a and 1a '. The sectional structure of the blocking plates 1 and 1 'may be a three-layer structure in which the non-magnetic spacing plates 8 and 8 are laminated on both sides of the magnetic plate 9 in the structure of FIG. Coil bobbin 4 with structure
The rear end side may have a structure in which only the magnetic plate 9 is provided.

By the way, since the blocking plates 1 and 1 'have the cutout portions 1a and 1a', the magnetic flux blocking effect is deteriorated only by the blocking plates 1 and 1 '. To compensate for this, a supplementary blocking plate 6 is used. The blocking plate 6 has a shape that just fills the continuous cutouts 1a and 1a 'when the blocking plates 1 and 1' are abutted.
That is, it is formed in a shape and size corresponding to the combination of the cutout portions 1a and 1a '. The cross-sectional structure of the blocking plate 6 is preferably a single-layer structure composed of only a magnetic plate.

The core halves 2, 2 ', the supports 3, 3', the coil bobbin 4, and the shim 5 other than the blocking plates 1, 1 'and 6 are the same as those of the conventional example described above.

Next, an assembling process of the assembly of each member of FIG. 1A in this embodiment will be described.

In the assembling process, first, the blocking plates 1 and the core halves 2 are alternately arranged and fixed at predetermined intervals in the track width direction of the core halves 2 with respect to the support 3 as shown in FIG. The blocking plate 1 'and the core half 2' are also fixed to the support 3 '.

Next, the coil bobbins 4 are fitted to the rear ends of the core halves 2, 2 ', respectively, and the shim 5 is sandwiched between the tip ends of the core halves 2, 2'. The assembly of the support 3 and the assembly of the blocking plate 1 ', the core half 2', and the support 3 'are butt-joined as shown by an arrow A in FIG. 1 (B).

Next, after the adhesive is applied to the peripheral portion of the supplementary blocking plate 6, the blocking plate 6 is inserted between the adjacent coil bobbins 4 as shown by an arrow B in FIG.
It fits into the notches 1a, 1a 'of 1' and is fixed by bonding. The cut-out portions 6a and 1a 'of the cut-off plates 1 and 1' are filled with the cut-off plate 6 to compensate for the lack of the magnetic flux blocking effect of the cut-off plates 1 and 1 '.

The assembly thus obtained is fitted and fixed to a magnetic head case (not shown) to form a magnetic head.

According to this embodiment, at the time of the above-mentioned abutting, the cut-off plates 1 and 1 'have the notches 1a and 1a', so that the coil bobbin 4 does not hit the cut-off plates 1 and 1 '. Further, when the supplementary blocking plate 6 is inserted between the coil bobbins 4 later and fitted and fixed to the cutout portions 1a, 1a 'of the blocking plates 1, 1', the coil winding 4a is wound around the coil bobbin 4. Since the corners of the portions are rounded, the blocking plate 6 can be inserted smoothly without being caught. Further, even if the mounting positions of the blocking plates 1, 1 'or the core halves 2, 2' with respect to the supports 3, 3 'are slightly shifted, if there is a gap between the coil bobbins 4 according to the thickness of the blocking plate 6, the blocking is performed. The plate 6 can be inserted and assembled.

Therefore, according to the present embodiment, the winding space of the coil winding 4a can be made larger than before, and the winding diameter of the coil winding 4a can be increased. Therefore, the sensitivity of the magnetic head can be improved by increasing the number of turns of the coil winding 4a. Alternatively, disconnection of the coil winding can be prevented by using a thick coil winding without changing the number of turns, and the reliability of the magnetic head can be improved.

Further, according to the present embodiment, a space for the coil winding can be secured with a margin compared with the conventional case, so that the size of the magnetic head can be reduced by saving the margin.

[Effects of the Invention] As is clear from the above description, according to the present invention, each of the structures in which the plurality of magnetic core halves and the shield plate for the magnetic shield are alternately supported in the track width direction by the support member and supported. A coil bobbin is fitted to the magnetic core half, and two sets of this structure are abutted and joined together, and a cutout portion is provided in a region near the coil bobbin of the blocking plate, and the cutout portion of the blocking plate is provided. In the magnetic head having a supplementary shielding plate having a shape to be compensated for, the shielding plate provided with the cutout portion is formed so that both sides of the magnetic plate are laminated with a non-magnetic plate, and the supplementary shielding plate is It is formed only by a magnetic plate, and its thickness is smaller than the thickness of the cut-off plate provided with the notch, so that the magnetic shield effect by the cut-off plate is considered as much as possible. An excellent effect of reducing the size of the above magnetic head and improving the assemblability while satisfying the size reduction can be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are top and rear views, respectively, of an embodiment of a magnetic head according to the present invention, illustrating an assembling process of an assembly comprising a core half, a blocking plate, a coil bobbin and a support. FIGS. 1A and 1B are top views showing the shape of the blocking plate in FIGS. 1A and 1B, and FIGS. 3A and 3B are top and rear views, respectively, for explaining an assembling process by a conventional method. FIG. 4 is a top view showing the shape of the blocking plate in FIGS. 3A and 3B, and FIGS. 5 and 6 are cross-sectional views of different conventional blocking plates and coil bobbins, respectively. 1,1 '... interrupting plate, 2,2' ... core half 3,3 '... support 4, ... coil bobbin 4a ... coil winding, 5 ... shim 6 ... supplementary insulating plate

Claims (1)

(57) [Claims] A coil bobbin is fitted to each magnetic core half of a structure in which a plurality of magnetic core halves and magnetic shield blocking plates are alternately arranged and supported in a track width direction by a support member. A magnetic head having a supplementary shielding plate in a shape in which a notch is provided in a region near the coil bobbin of the shielding plate and the notch of the shielding plate is filled. The cut-off plate provided with the cutout portion is formed so that both sides of the magnetic plate are laminated with a non-magnetic plate, and the supplementary cut-off plate is formed only of the magnetic plate, and the thickness thereof is A magnetic head characterized in that it is thinner than a thickness of a blocking plate provided with a notch.