JPH0652562B2 - Magnetic head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, and more specifically, in an induction type magnetic head for recording, reproducing or erasing information by sliding contact with a magnetic recording medium, a coil winding. The present invention relates to a magnetic head having a bobbin that is wound around and fitted to a magnetic core.

[Prior Art] A conventional structure of a full width erasing head used in a video tape recorder as an example of this type of magnetic head is as shown in FIGS. 3 and 4.

In both figures, reference numeral 1 is a magnetic core, and the magnetic spacer 6 is flush with the tip surface of the core body 1a via the magnetic gaps 7 in the groove 1b of the core body 1a having a U-shaped cross section. It is configured by fitting and fixing.

Reference numeral 2 is a winding bobbin, around which a coil winding 4 is wound, the end of this coil winding is connected and the terminal 3 is planted at the rear end, and a hole (not shown) is 4 is formed so as to penetrate vertically.

Then, the winding bobbin 2 fitted and fixed to one of the core bodies 1a of the magnetic core 1 through the holes is fitted in the case 5, and the tip end surface (magnetic field) of the magnetic core 1 having the magnetic gaps 7, 7 is The tape sliding surface) is exposed from an opening 5a formed in the front surface of the case 5 and fixed to form a magnetic head.

[Problems to be Solved by the Invention] In the structure of the full width erasing head described above, as shown in FIG. There is a case where a portion contacts the magnetic core 1 and the coil winding 4 and the magnetic core 1 are short-circuited, and as a result, the function as the magnetic head cannot be satisfied. Particularly, in the full width erasing head, the track width T shown in FIG. 3 is required to be wider than the magnetic tape width, so that the winding bobbin 2 becomes elongated,
Since the coil winding 4 is largely lifted and overhang due to slack and looseness, the above-mentioned contact and short circuit easily occur.

In order to prevent this short circuit, a method of pasting an insulating tape to the coil winding 4 or the magnetic core 1 has been conventionally used, but the number of expanded parts and the number of assembling steps increase.

This problem is not limited to the full-width erasing head, but is common to magnetic heads having similar bobbins.

[Means for Solving the Problems] In order to solve the above-mentioned problems, according to the present invention, one protrusion of the magnetic core formed in a substantially U shape by having two protrusions, In a magnetic head in which a bobbin around which a coil winding is wound is fitted, an insulating member that regulates the height of the coil winding from the winding surface is provided on the other protruding portion of the magnetic core of the bobbin. A structure is provided that is integrally provided on the winding surface side that faces the coil winding and that prevents the coil winding from contacting the other protruding portion of the magnetic core.

[Operation] According to the above structure, due to the regulation of the above-mentioned insulating member, the floating from the winding surface of the coil winding, the contact with the magnetic core due to the overhang, and the short circuit are surely prevented. Therefore, the conventional insulating tape becomes unnecessary, and the number of parts and the number of assembling steps can be reduced accordingly.

Embodiments Embodiments of the present invention will be described in detail below with reference to FIGS. 1 and 2. Here, the above-described full-width erasing head is used as an example, and the same or corresponding parts in FIGS. 1 and 2 as those in FIGS. 3 and 4 are designated by the same reference numerals.

FIG. 1 is an exploded perspective view of a core body and a winding bobbin of a magnetic core of a head according to this embodiment.

As shown in the figure, the core body 1a has a groove 1b as in the conventional case, and is formed of a high magnetic permeability material such as ferrite, permalloy or sendust in a block shape having a U-shaped cross section.

On the other hand, the winding bobbin 2 has flange portions 2a and 2b for restricting the winding width of the coil winding 4 wound around the winding bobbin 2 and has an insulating material such as plastic in a rectangular tube shape having a hole 2c penetrating therethrough. Are formed from. And the flange portion 2 on the rear end side
Terminals 3, 3 to which the ends of the coil winding 4 are connected are planted on the rear end faces of both ends bent in a U shape in b.

The structure of the winding bobbin 2 in the portion described above is the same as the conventional one, but in the present embodiment, in addition to this, the flange portion 2 on the rear end side is added.
An elongated rectangular plate-shaped convex portion 2d is integrally provided on the flange portion 2b at a central portion of a side edge thereof facing the core body 1a of b. The convex portion 2d has an insulating property and elasticity that can be easily bent, depending on the material of the bobbin, and has a length slightly longer than the distance between the flange portions 2a and 2b. Further, a groove 2e is formed at a position of the flange portion 2a on the tip end side corresponding to the convex portion 2d on the side edge facing the core body 1a. The groove 2e is a relief that fits when the convex portion 2d is bent as described later, and has a width and a predetermined depth slightly larger than the convex portion 2d.

Based on this structure, the winding bobbin 2 is provided through the hole 2c on one side of the core body 1a as shown by the one-dot chain line in FIG.
Are fitted and fixed. As shown in FIG. 2, the magnetic spacer 6 is fitted and fixed in the groove 1b of the core body 1a so as to be flush with the tip end surface (magnetic tape sliding surface) of the core body 1a via the magnetic gaps 7,7. . The magnetic spacer 6 is the core body 1
It is made of a high magnetic permeability material similar to that of a.

Further, as shown in FIG. 2, the assembly of the magnetic core 1 and the winding bobbin 2 is fitted and fixed in the same manner as in the case of the conventional example described above in the case 5 formed by molding of plastic or the like, and the full width erasing head. Is configured.

When the winding bobbin 2 is fitted into the core body 1a as described above, the convex portion 2d of the winding bobbin 2 is in contact with the inner surface of the groove 1b of the core body 1a as shown in FIG. , 2
It is bent so as to bridge b and is interposed between the winding surface of the coil winding 4 of the winding bobbin 2 and the inner surface of the groove 1 a of the magnetic core 1. The tip of the convex portion 2d is fitted into the groove 2e as described above. Then, as shown in FIG.
The height from the winding surface of the
Since it is regulated below the right end of a and 2b in the figure, contact and short circuit with the magnetic core 1 due to the floating and overhanging of the coil winding 4 can be reliably prevented.

As described above, according to the structure of this embodiment, the convex portion 2d can surely prevent the coil winding 4 and the magnetic core 1 from coming into contact with each other and short-circuiting. Therefore, the conventional insulating tape is not necessary. Since the convex portion 2d is formed integrally with the winding bobbin 2, the number of parts is not increased by that amount, and no special process is required for bending the winding bobbin 2. And the number of assembly steps can be reduced by the amount of the attaching step.

In the structure of this embodiment described above, the number of convex portions 2d is one.
Of course, the number is not limited to one, and a plurality may be provided, and in that case, the position to be provided is not limited to the central portion. Further, the width may be increased and the shape structure is not limited to the rectangular plate shape.

Furthermore, it goes without saying that such a structure in which the convex portion 2d is provided can be applied not only to the full width erasing head but also to all magnetic heads having a winding bobbin.

[Effect] As is apparent from the above description, according to the present invention, the coil winding is wound around one of the protrusions of the magnetic core which is formed in a substantially U shape by having two protrusions. In a magnetic head in which a wound bobbin is fitted, an insulating member that regulates the height from the winding surface of the coil winding is wound so as to face the other protruding portion of the magnetic core of the bobbin. Since the structure is provided integrally on the surface side to prevent contact between the coil winding and the other protruding portion of the magnetic core, contact with the magnetic core due to slack or looseness of the coil winding, and short-circuiting are surely performed. In addition to being able to prevent it, it is possible to obtain an excellent effect that the cost can be reduced by reducing the number of parts and the number of assembling steps.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a main body of a magnetic core and a winding bobbin of a full width erase head according to an embodiment of the present invention, FIG. 2 is a sectional view showing the entire structure of the head, and FIGS. 3 and 4 are respectively. It is the front view and sectional drawing which show the structure of the conventional full width erasing head. 1 ... Magnetic core, 2 ... Winding bobbin 2d ... Convex portion, 2e ... Groove 3 ... Terminal, 4 ... Coil winding 5 ... Case, 6 ... Magnetic spacer 7 ... Magnetic gap

Claims (1)

[Claims] 1. A magnetic head in which a bobbin around which a coil winding is wound is fitted to one of the protrusions of a magnetic core formed in a substantially U shape by having two protrusions. An insulating member that regulates the height of the coil winding from the winding surface is integrally provided on the winding surface side of the bobbin facing the other protruding portion of the magnetic core, and the coil winding and the magnetic A magnetic head characterized by preventing contact with the other protruding portion of the core.