JPH0475561B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a magnetic head, and more particularly to a magnetic head having a mounting member and a magnetic shielding member.

[Prior art]

A magnetic head for VTR audio is known as this type of magnetic head, and this magnetic head includes a mounting member for attaching the magnetic head to the main body of the VTR device, and a shield, which is a magnetic shield member for shielding externally induced noise. A cap is provided.

Figure 1 explains the structure of a conventional magnetic head for VTR audio.The magnetic head 1 is constructed as a composite head in which a recording/reproducing head 1A and an erasing head 1B are integrally provided in parallel. Both heads are provided with sliding surfaces 1a and 1b facing a magnetic core (not shown) that slides into contact with the magnetic tape for recording, reproducing, or erasing.
The above-mentioned shield cap 2 is fixed to the upper surface of the magnetic head 1 in the figure adjacent to the sliding surfaces 1a and 1b by adhesive or spot welding. The shield cap 2 is formed into a plate shape from a material such as permalloy, and has a bent portion 2a bent toward the upper end of the sliding surface 1a, and bent portions 2b, 2b (one of which is free) that holds the magnetic head 1 from both sides. ). The mounting plate 3, which is the above-mentioned mounting member, is further placed on top of the shield cap 2.
It is fixed on the magnetic head 1 by screws 4,4.
This mounting plate 3 is formed into a quadrilateral shape and has holes 3a at its four corners. By fixing the mounting plate 3 to the VTR device main body with screws etc. through these holes 3a, the magnetic head 1 can be attached to the VTR device. mounted on.

In addition to the above-mentioned method of fixing the shield cap 2 and mounting plate 3 to the magnetic head 1, as a fixing method, the shield cap 2 and the mounting plate 3 are overlapped and attached to the magnetic head 1 using screws 4 at the same time. There is a way to fix it with screws.

However, in the above structure, the former method of fixing the shield cap 2 and the mounting plate 3 requires a separate process of first fixing the shield cap 2 and then fixing the mounting plate 3 with screws. In the latter method, it is difficult to position the shield cap 2 with respect to the magnetic head 1, resulting in a low yield of finished products and high costs. It was hot.

The above drawbacks are not limited to the magnetic head for VTR audio described above, but are common to magnetic heads having mounting members and magnetic shielding members similar to those described above.

〔the purpose〕

The present invention has been made to eliminate the above-mentioned conventional drawbacks, and an object of the present invention is to provide an inexpensive magnetic head that is easy to assemble and has a high yield.

〔Example〕

Hereinafter, an embodiment in which the present invention is applied to the above-mentioned VTR audio magnetic head will be described in detail with reference to FIG. 2 and subsequent figures. In each figure, the same reference numerals are given to the same or corresponding members as in FIG. 1, and explanations of the same members will be omitted.

[First Embodiment] FIGS. 2 and 3 illustrate a first embodiment of the present invention. As shown in both figures, in this embodiment, the shield cap described above is not provided, and a mounting plate 3 is attached to the top surface of the magnetic head 1 with screws 4,
It is directly fixed by 4.

The mounting plate 3 is made of a magnetic material and is formed into a quadrilateral shape with holes 3a at four corners, similar to the conventional example.

The mounting plate 3 is also formed with a protrusion 3b cut and raised by a press so as to face the sliding surface 1a on the near side of the sliding surface 1a.

According to the above structure, the magnetic head 1 is magnetically shielded by the mounting plate 3 made of a magnetic material. In particular, the recording/reproducing head 1A is shielded via the projection 3b.

By the way, when the material of the mounting plate 3 was made of permalloy, which is used in ordinary shield caps, the amount of externally induced noise was reduced by about 5 to 8 dB compared to when no shield member was attached.

Furthermore, even when iron (JIS standard SPCC material), which is commonly used as the material for conventional mounting plates, was used, the amount of externally induced noise was reduced by more than 2 dB.

Furthermore, according to this embodiment, the conventional fixing process for the shield cap can be omitted in the assembly process, and the number of parts can be reduced accordingly. Also, the protruding piece 3b
The positional accuracy of the magnetic head 1 with respect to the magnetic head 1 can be achieved with high accuracy by the positional accuracy when forming the not-shown screw holes for the projections 3b and the screws 4, and the position is adjusted when the mounting plate 3 is fixed. There's no need.

[Second Embodiment] FIG. 4 illustrates a second embodiment of the present invention, in which the mounting plate 3 is fixed to the magnetic head 1 by spot welding at the welded portion 3c. There is.

According to this method, the screw 4 of the first embodiment described above
This eliminates the need for screw holes, which further reduces the number of parts and simplifies the structure.

Note that the projecting piece 3b of the mounting plate 3 may be provided by other methods such as integrally molding by casting instead of cutting and bending.

Further, the structure of the present invention is of course applicable not only to the VTR audio magnetic head of the embodiment but also to other magnetic heads having a mounting member and a magnetic shielding member.

〔effect〕

As is clear from the above description, the magnetic head of the present invention has a magnetic head on which a sliding surface is formed, and a mounting member for mounting the magnetic head on the main body of the apparatus, and the mounting member is made of a magnetic material. A structure is adopted in which a protruding piece for magnetic shielding is cut and raised in a part of the magnetic head, and the protruding piece is placed in front of the sliding surface of the magnetic head to fix the mounting member to the magnetic head. Therefore, the magnetic head can be magnetically shielded by the mounting member made of magnetic material, and in particular, the protruding piece of the mounting member placed in front of the sliding surface of the magnetic head prevents the most influence of the inflow from the front of the sliding surface of the magnetic head. It is possible to effectively shield against high-frequency noise. In addition, the number of parts is reduced, the assembly process is simplified, and the positional accuracy of the magnetic shield part can be improved.
Since the yield is improved, it has the effect of significantly reducing costs.

[Brief explanation of the drawing]

1 is a perspective view of a conventional magnetic head, FIG. 2 is a perspective view of a magnetic head according to a first embodiment of the present invention, and FIG. 3 is a partially cutaway side view of the magnetic head shown in FIG. FIG. 4 is a perspective view of a magnetic head according to a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Magnetic head, 1a, 1b... Sliding surface, 3... Mounting plate, 3a... Hole, 3b... Projection piece, 3c... Welding part,
4...Screw.

Claims (1)

[Claims] 1 It has a magnetic head with a sliding surface formed thereon and a mounting member for mounting the magnetic head on the main body of the device, and this mounting member is made of a magnetic material, and a protruding piece for magnetic shielding is cut into a part of the mounting member. 1. A magnetic head, characterized in that the mounting member is fixed to the magnetic head by raising the protruding piece in front of the sliding surface of the magnetic head.