JPS6338409Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a magnetic head device.

In magnetic head devices for audio etc.
Generally, a structure is adopted in which a pair of core halves are brought together between a pair of core holders so as to form a magnetic gap between their front ends, and housed in this state in a shield case.

On the other hand, when the core material is made of a conductive magnetic material such as permalloy or sendust, each core half is made of a laminated type in which thin core half pieces are laminated to reduce eddy current loss. The core is half. In this case, it is necessary to mechanically integrate the core halves while stacking them together, but normally, the integration of the laminated core halves and their fixation within the core holder are done using resin. Adhesive and spring press methods are used. However, with this method, external force is applied to the core due to volumetric contraction of the resin, causing deterioration of magnetic properties such as a decrease in magnetic permeability. Also, the integration between the core holder halves is usually
This is done by screwing, etc., but in this case, the operating magnetic gap between the core holder halves, and therefore between the front ends of the core halves, may be misaligned, resulting in deterioration of the magnetic properties or Becomes unstable. Further, the fixation between the holder and the shield case is usually done by casting resin, but even in this case, the shrinkage of the resin affects the characteristics as described above.

The present invention makes it possible to avoid the above-mentioned drawbacks. In particular, the present invention requires the integration of the laminated core pieces of each core half, which have a great influence on the magnetic properties, and the integration of these core halves. The present invention provides a magnetic head device which adopts a special configuration to prevent deterioration and stabilize characteristics when integrated with a core holder half.

An example of a magnetic head device according to the present invention will be described in detail with reference to FIGS. 1 to 9.

In the figure, numeral 1 shows the magnetic head device according to the present invention as a whole.

Also in the present invention, a pair of core holder halves 3a and 3b are placed inside the shield case 2 as usual.
are abutted and combined, a pair of core halves 4a and 4b are abutted between both core holder halves 3a and 3b, and an operating magnetic gap g is formed between the front ends of both core halves 4a and 4b. It is made to be formed.

The holder halves 3a and 3b are made of zinc die-casting, for example, as shown in FIG.
A jetty 7 is provided with a flat abutting surface 6 formed on the front edge and the upper and lower side edges sandwiching the front edge so as to form a recess 5 on the opposing surfaces. Grooves 8 are provided across the front end of the jetty 7 and into the recess 5, into which the core halves 4a and 4b are inserted and whose positions are regulated.

The core halves 4a and 4b are each made of a magnetic thin plate such as Permalloy or Sendust, and core halves punched in a U-shape are laminated, and the laminated core halves 4a and 4b are further sandwiched between them. So-called non-magnetic dummy core pieces 9a ₁ , 9a ₂ and 9 formed of elastic metal plates such as phosphor bronze are used.
b ₁ and 9b ₂ are arranged in a stacked manner. Each core half 4a
and 4b, that is, the dummy cores (9a ₂ and 9b ₂ in the illustrated example), have their rear ends bent so as to spread outward, and their free ends connect to the core holder halves 3a and 3b. The core halves 4a and 4b are elastically abutted against the inner surface of the jetty 7 to push the core halves 4a and 4b to one side of the groove 8, respectively.
b is held within the groove 8. Further, a protrusion 10 is formed on each of the core halves 4a and 4b, that is, on a laminate of core half pieces made of magnetic thin plates constituting these halves 4a and 4b and a dummy core made of a non-magnetic thin plate. do. This protrusion 10 itself has two core halves 4a and 4b.
The magnetic head is located outside the main closed magnetic path of the magnetic head formed by the butt of the magnetic head, and is provided so as to protrude outward from this magnetic path. In this example, in the middle part of the U-shaped core halves 4a and 4b,
They are provided so as to protrude on the side opposite to the sides that are brought into contact with each other.

On the other hand, the protrusions 10 of the husband's core halves 4a and 4b are inserted into the core holder halves 3a and 3b, and a window 11 is provided to expose the outer end surface of each protrusion 10 to the outside.

These, the protrusion 10 and the window 1 into which it is inserted.
In No. 1, the arrangement position and orientation of the protrusion 10 are selected so that the outer end surface of the protrusion 10 can pass through to the outside other than the abutment surface of the core halves.

Note that 12 indicates at least one core half 4a, 4b.
This is the head winding wound on top.

In this way, each core half body 4a and 4b is inserted into each core holder half body 3a and 3b into its groove 8, and with each protrusion 10 inserted into the window part 11, each window On the outer end surface of each protrusion 10 exposed to the outside through the portion 11, each core piece in each core half body 4a and 4b and a non-magnetic dummy core plate are surrounded by a chain line marked with a symbol a in FIG. 9a and 9b, and furthermore, the window portion 11
Welding is performed by laser beam irradiation or electron beam irradiation across the core holder halves 3a and 3b around the core holder halves 4a and 4.
In b, the laminate is integrated, and each core half body 4a and 4b and its core holder half body 3 are integrated.
a and 3b are connected and integrated. In this case, if the welded parts protrude from the outer surface of each core holder half body 3a and 3b, it will interfere with insertion into the shield case 2, so a recessed part 11a is provided on the outside of the window part 11 so that this welded part protrudes from the outer surface of the holder half body 3a. And it can be made so that it does not protrude from the outer surface of 3b.

The core holder halves 3a and 3b to which these laminated and integrated core halves 4a and 4b are attached, respectively, are attached to each other.
b are butted together, and both core halves 4a and 4
For example, connect each jetty 7 via a non-magnetic gear spacer so that the front ends of
are abutted so that their end surfaces abut, and in this state, the above-mentioned Similarly, the core holder halves 3a and 3b are welded together by laser beam irradiation or electron beam irradiation, for example, to join them together. Furthermore, both core holder halves 3a
A mask 12 is applied to the front surface of and 3b,
The mask 12 is attached to the holder halves 3a and 3b at its periphery by welding by laser beam or electron beam irradiation, as shown surrounded by the chain line marked c in FIG. The mask 12 is made of a material that has the same coefficient of friction between the core halves 4a and 4b and the magnetic medium brought into contact with them, as well as wear resistance and the like as much as possible. For example, if the core halves 4a and 4b are made of sendust, the mask 1
2 is made of sendust, and when the core halves 4a and 4b are made of permalloy, they are made of Fe-Ni based material. This mask 12 has a magnetic gap g of the core.
The mask 12 forms an opposing surface with the same magnetic medium, but the provision of this mask 12 has the additional benefit of reinforcing that the two core holder halves 3a and 3b can be more firmly joined together. It's also effective.

These combined core holder halves 3a and 3
b is inserted into the shield case 2, and both core halves 4 are inserted through the window 13 provided in the front plate part of the shield case 2.
The front surfaces of the actuating magnetic gaps g of a and 4b and the front surface of the mask 12, that is, the surface in contact with the magnetic medium, are exposed to the outside.

The shield case 2 and the core holder halves 3a and 3b are, as shown in FIG.
As shown by the chain line marked with d along the edge of the window 12, the case 2, the mask 12, and the core half 4a
and 4b are mechanically combined by welding with laser light irradiation and electron beam irradiation. Furthermore, if necessary, protrusions 14 are provided on the side surfaces of both holder halves 3a and 3b, and on the other hand, notches 15 are provided in the shield case 2 into which these protrusions 14 are inserted, and the fitting edges of both are marked with a symbol e. Welding can also be performed by a method similar to that described above, as shown by the dashed line.

As described above, according to the configuration of the present invention, in particular, the laminated combination of the core halves 4a and 4b, these core halves 4a and 4b, and the core holder halves 3a and 3
By making the connection with b by welding and avoiding resin adhesion and filling, it is possible to avoid characteristic deterioration and instability due to resin shrinkage as described at the beginning.

In the present configuration, the protrusions 10 are provided on the core halves 4a and 4b, and these are welded through the windows 11 of the core holder halves 3a and 3b at a position away from the magnetic path. , it is possible to avoid an increase in eddy current loss due to this welding.

In the above example, the protrusion 10 and the window 11 are provided at the intermediate portion of the core halves 4a and 4b, but in some cases, as shown in FIG. Core half 4 with or without protrusion 10 and window 11 in the intermediate part
A protrusion 10 is provided at the rear ends of a and 4b other than the portion forming the magnetic path, and this protrusion 10 and the inner surfaces of the core holder halves 3a and 3b are on the same plane, which is indicated by a chain line with the symbol f. Such welding can also be performed by a method similar to that described above.

In addition to welding the protrusion 10 and the edge of the window 11, the core half 4a is welded together with the welded portion as necessary to prevent a current path loop from forming.
It is also possible to perform similar welding to combine the laminates at other parts than the mutual abutting surfaces of and 4b.

Furthermore, in the illustrated example, the present invention is applied to a single-element magnetic head device. The present invention can also be applied to a multi-element magnetic head device. In this case, a shield plate is inserted between each element.

[Brief explanation of the drawing]

Fig. 1 is an enlarged top view with a part of the shield case of an example of the magnetic head device according to the present invention cut away, Fig. 2 is an enlarged front view thereof, and Fig. 3 is a similar part of the shield case. An enlarged cutaway side view, Fig. 4 is an enlarged top view with the shield case removed, Fig. 5 is an enlarged front view,
Figure 6 is an enlarged side view, and Figure 7 is A- of Figure 6.
8 is an enlarged sectional view taken along line A--A in FIG. 5, and FIG. 9 shows a state in which the core half of an example of the magnetic head device according to the present invention is placed in the core holder half. FIG. 10 is a similar enlarged perspective view of another example of the magnetic head device according to the present invention. 1 is a magnetic head device according to the present invention, 2 is a shield case, 3a and 3b are core holder halves, 4
a and 4b are core halves, 10 is a protrusion, and 11 is a window.

Claims (1)

[Scope of utility model registration request] In a magnetic head device in which a pair of core halves are brought together and held by a pair of core holder halves, the pair of core halves are formed by laminating a plurality of core half pieces. A protrusion protruding outward is provided in a portion of each of the laminated core halves other than the portion constituting the main magnetic path, and the protrusion of each of the core halves is inserted into each of the core holder halves. A window is provided that extends beyond the abutting surfaces of the core halves, and the core half piece and the holder half are welded together at the protrusion inserted into the window, and the core halves are welded together. A magnetic head device comprising core holder halves having the above-mentioned core halves, which are integrated with each other with a required gap between the front abutting surfaces of the core halves.