JPH08147656A - Magnetic head assembly - Google Patents

Abstract

PURPOSE: To reduce production costs and thin an FD apparatus by reducing a count of members. CONSTITUTION: A shielding material A2 is arranged as an electromagnetic shield at a mounting part of an FPC 1 to a slider assembly in order to shut, external noises. The FPC 1 transmits electric signals from a head assembly recording/reproducing data to an FD medium. The shielding material is obtained by layering magnetic bodies, conductive bodies or, both magnetic bodies and conductive bodies. The magnetic bodies or conductive bodies may be of the same material or magnetic bodies of different materials may be layered. A gimbals is formed by slits 3a, 3b in place of a conventional gimbals, whereby a count of members is decreased. A count of members is reduced and a count of assembling steps is decreased, so that an inexpensive compact, magnetic head assembly is provided. As a result, an FD apparatus is easily thinned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head assembly used in a flexible disk device, and more particularly to a shield structure for the magnetic head assembly.

[0002]

2. Description of the Related Art A conventional magnetic head assembly will be described with reference to the drawings.

FIG. 5 is an exploded perspective view for explaining a conventional method of assembling a general magnetic head assembly. As shown in FIG. 5, the magnetic head of this conventional example has a read / write coil 18a, an erase coil 18b, and a read / write coil 18a for writing / reading information to / from a flexible disk medium (not shown, hereinafter referred to as FD medium). Terminal 19
A magnetic core 14 including a slider A15 and a slider B1.
A slider assembly 17 held by 6 is provided. Further, since the slider assembly 17 freely follows displacements such as waviness and vibration during rotation of the FD medium, the surface opposite to the contact surface where the slider assembly 17 contacts the FD medium (back surface of the slider assembly 17). Includes a thin plate-shaped elastic member (for example,
A gimbal 26 made of stainless alloy is attached.

The gimbal 26 is provided with a slit 28 for freely following the displacement of the FD medium during rotation, so that the slider assembly 17 can move in the pitch direction (arrow C).
Can freely behave in the roll direction) and the roll direction (direction of arrow D). Also, on the back of the gimbal 26,
A flexible print circuit (hereinafter, referred to as FPC) 29 for transmitting a signal obtained via the terminal 19 to a recording / reproducing circuit (not shown) is attached. Further, in order to shield external noise, a shield material C25 is arranged around the slider assembly 17 as an electromagnetic shield member for shielding external noise. Generally, the assembly in this state is called a flexure assembly.

In the flexure assembly, the positioning boss 24 provided on the resin-molded holder 23 is used to move the FD medium up and down when it is inserted and ejected.
A positioning hole 27 provided in the gimbal 26 is attached to and bonded to the gimbal 26. Therefore, this magnetic head assembly is composed of five members (slider assembly, gimbal, FPC, electromagnetic shield member and holder), which are assembled by adhesion.

FIG. 6 is a sectional view showing a section taken along the line D-D 'of the FPC 29 of FIG. 5, and FIG. 6A shows a circuit pattern 6a, 6b, 6c bonded on the base film 5 to be assembled. It is a thing. Further, in FIG. 6B, the circuit patterns 6a, 6b, 6c are adhered on the base film 5, and the cover film 7 is provided in a space other than the circuit patterns 6a, 6b, 6c.

Next, another conventional magnetic head assembly will be described.

FIG. 7 is a view showing a known example disclosed in Japanese Utility Model Laid-Open No. Sho 63-168618, and FIG.
FIG. 7 (b) is a developed perspective view showing the magnetic head assembly.
FIG. 8 is a perspective view seen from the back surface of FIG.

In FIGS. 7A and 7B, in this magnetic head assembly, the slider assembly 71 has a magnetic head support plate 7 having a head mounting portion 74a and a lead portion 74b.
4 is directly glued and fixed. This head mounting portion 74a
Is provided with a positioning hole 73 for adjusting the position when the magnetic head assembly is fixed to a carriage (not shown), and a coil 72 of the slider assembly 71 is connected to the circuit pattern 75 at the center. An opening 76 is provided.

Although not shown, in order to avoid an adverse effect due to external noise, the periphery of the slider assembly 71,
Alternatively, a shield material is arranged on the opposite surface of the carriage to which the magnetic head is attached, or with the slider assembly 71 as a base. Therefore, this known example is composed of at least four members.

[0011]

The above-described conventional magnetic head assembly has a structure in which at least four members are bonded and fixed, so that the number of the constituent members is large and the number of assembling steps is large, which is expensive. There are drawbacks.

An object of the present invention is to solve the above problems, to reduce the number of members and the number of assembling steps, to provide an inexpensive magnetic head assembly, and also to downsize the magnetic head assembly to realize an FD device. The purpose is to enable thinning.

[0013]

SUMMARY OF THE INVENTION According to the present invention, a magnetic head having a magnetic core for recording / reproducing on / from a recording medium, and the magnetic head disposed at a mounting portion provided at one end to transmit an electric signal. In a magnetic head assembly including a flexible printed circuit, the mounting portion of the flexible printed circuit is formed by laminating an electromagnetic shield member made of a magnetic material or a conductor.

A gimbal formed by a slit is formed in the mounting portion of the flexible printed circuit so that the magnetic head can follow the displacement of the recording medium.

The electromagnetic shield member may be a magnetic body or a conductor only, or a laminated body of a magnetic body and a conductor, and the magnetic body and the conductor are magnetic materials made of the same material or different materials. May be laminated.

[0016]

Next, the present invention will be described with reference to the drawings.

FIG. 3 is a view showing details of the flexure assembly constituting the magnetic head assembly of the present invention.
FIG. 3A is a side view, and FIG. 3B is a view on arrow C in FIG. 3A and 3B, the flexure assembly 13 includes a read / write coil 18a and an erase coil 1 for a slider assembly 17 in which a magnetic core 14 is sandwiched between a slider A15 and a slider B16.
8b is inserted into the magnetic core 14, and an assembly in which the side surface of the magnetic core 14 is adhered and fixed by the magnetic body 20 is formed into a base film 5, a circuit pattern 6, and a cover film F.
It has a structure in which it is fixed to the PC 1 with an adhesive 21. The terminals 19 provided on the read / write coil 18a and the erase coil 18b are connected to the FPC by solder 22.
1 is electrically connected to the circuit pattern 6.

FIG. 4 is a developed perspective view for explaining the method of assembling the magnetic head assembly of the present invention.

Referring to FIG. 4, first, slider assembly 17
Is bonded to a predetermined position of the FPC 1 and the terminals of the slider assembly 17 are connected to form the flexure assembly 13. Subsequently, the flexure assembly 13 is bonded and fixed to the resin-molded holder 23. Here, the positioning boss 2 provided on the holder 23 is used for positioning at the time of bonding.
4 are inserted into the positioning holes 4a and 4b provided in the FPC 1 for positioning.

Since the magnetic head assembly of the present invention freely follows the undulations and vibrations generated when the FD medium rotates,
For the operation in the pitch direction, the slits 3a and 3b are provided around the attachment portion of the slider assembly 17 of the FPC 1 and the arrow A
The movement in the roll direction is configured to follow the direction of arrow B by twisting the convex portion of the FPC 1 for providing the positioning holes 4a and 4b.

When the gimbal 26 is used, the slider assembly 17 may be attached to the FPC 1 via the gimbal 26. In this case, since the gimbal 26 has a shield effect against external noise, it is not necessary to dispose a shield material around the slider assembly 17.

Next, FIG. 1 is a diagram showing the configuration of an embodiment of the present invention.

Here, FIG. 1A is a perspective view showing an FPC which is a main part of the magnetic head assembly.
2 shows the slider mounting portion as seen from the back surface opposite to the surface to which the slider assembly is attached. A circuit pattern 6 for electrically connecting the slider assembly and the recording / reproducing circuit is arranged on the slider mounting portion. Further, a shield material A2 is arranged as an electromagnetic shield member for shielding external noise at a portion where the circuit pattern 6 is absent. The opening 11 is an opening for connecting the circuit pattern 6 and a terminal of a slider assembly (not shown) by soldering.

As described with reference to FIG. 5, the slits 3a and 3b allow the FD medium to follow the displacement in the pitch direction with respect to displacements such as waviness and vibrations caused by the rotation of the FD medium, and the positioning hole 4a. , 4b is made to follow in the roll direction by the twisting motion of the convex portion.
Further, the followability is also improved by providing the portion 12 without the cover file and reducing the rigidity.

FIG. 1B is a sectional view showing a section taken along the line AA 'in FIG. 1A, showing the details of the movable portion of the FPC 1. As shown in FIG. 1B, the movable portion of the FPC 1 serves as a circuit turn 6 that is electrically connected to the terminals of the slider assembly and transmits various signals.
The circuit turns 6a, 6b, 6c, 6d, 6e are arranged on the top, and they are covered with the cover film 7.

Next, FIGS. 2 (a) to 2 (d) are sectional views showing a cross section taken along the line BB 'of FIG. 1 (a).
Each embodiment is shown when the FPC configuration is different.

First, in the FPC shown in FIG. 2A, a circuit pattern 6 for transmitting an electromagnetically converted signal is arranged on the base film 5. An example of the circuit pattern 6 is copper foil. Further, the shield material A2 is arranged at a position at the same height where it does not conduct with the circuit pattern 6 (a portion shown by hatching in FIG. 1). The material of this shield material A2 is copper foil, Fe-Ni
It is made of alloy or the like and is covered with a cover film 7 on its upper surface. However, the cover film 7 is cut at a place where the terminals 19 of the read / write coil 18a and the erase coil 18b are electrically connected to the circuit pattern 6 and in the vicinity thereof.

As a result, it is possible to reduce the influence of external noise on the slider assembly 17, which is the electromagnetic converter. 3a and 3b are slit cross sections, and 4
Reference numerals a and 4b show cross sections of the positioning holes.

Next, in the case of FIG. 2B, a shield material B8 is further arranged on the shield material A2 shown in FIG. 2A to obtain a shield effect by lamination. The material of the shield material B8 is copper foil, Fe-Ni alloy, or the like. Further, in the case of FIG. 2C, the insulating sheet 10 on the circuit pattern 6 is arranged, and the shield material A is attached on the entire surface thereof, and the cover film 7 is arranged. It should be noted that the cover film 7,
The shield material A2 and the insulating sheet 10 are cut. As a result, the shield material A can be arranged in a wide range, and the shield effect is increased. Furthermore, FIG.
In the case of (d), the shield material B8 and the cover film 7 are arranged on the upper surface of the shield material A2 shown in FIG. 2 (c). As a result, FIG. 2 (b) and FIG. 2 (c)
It is possible to obtain the same shielding effect as that of the FPC shown in FIG.

Regarding the combination of the shield material A2 and the shield material B8, for example, only a magnetic body or a conductor, a laminated body of a magnetic body or a conductor, a laminated body of a magnetic body or a conductor of a different material, and a magnetic body And a conductor are laminated, and a good shield effect can be obtained with any combination of these.

[0031]

As described above, in the magnetic head assembly of the present invention, the shield material is arranged around the slider assembly mounting portion on the FPC as an electromagnetic shield member for shielding external noise, and the slit is formed by the slit. By forming the gimbal, the number of members and the number of assembling steps can be reduced, an inexpensive and small magnetic head assembly can be provided, and the FD device can be thinned.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a cross section taken along the line BB ′ of FIG.

FIG. 3 is a diagram showing a flexure assembly that constitutes a magnetic head assembly of the present invention.

FIG. 4 is a developed perspective view for explaining assembly of a magnetic head assembly according to the present invention.

FIG. 5 is an exploded perspective view illustrating a conventional method of assembling a magnetic head assembly.

FIG. 6 is a cross-sectional view showing a cross section taken along the line DD ′ of FIG. 1.

FIG. 7 is a perspective view showing another conventional magnetic head assembly.

[Explanation of symbols]

 1,29 FPC 2 Shield material A 3a, 3b, 28 Slit 4a, 4b, 27, 73 Positioning hole 5 Base film 6, 6a-6e, 75 Circuit pattern 7 Cover film 8 Shield material B 9 Adhesive part 10 Insulating sheet 11 , 76 opening 12 part without cover film 13 flexure assembly 14 magnetic core 15 slider A 16 slider B 17,71 slider assembly 18a read / write coil 18b erase coil 19 terminal 20 magnetic material 21 adhesive 22 solder 23 holder 24 positioning boss 25 shield material C 26 gimbal 72 coil 74 magnetic head support plate 74a head mounting portion 74b lead portion

Claims (6)

[Claims] 1. A magnetic head having a magnetic core for recording / reproducing on / from a recording medium, and a flexible printed circuit for arranging the magnetic head at a mounting portion provided at one end to transmit an electric signal. In the magnetic head assembly, the mounting portion of the flexible printed circuit is formed by laminating an electromagnetic shield member made of a magnetic material or a conductor. 2. The magnetic head assembly according to claim 1, wherein a gimbal formed by a slit is formed in the mounting portion of the flexible printed circuit so that the magnetic head can follow the displacement of the recording medium. Three-dimensional. 3. The magnetic head assembly according to claim 1, wherein the electromagnetic shield member is made of a magnetic material or a conductor. 4. The magnetic head assembly according to claim 1, wherein the electromagnetic shield member is formed by laminating a magnetic body and a conductor. 5. The magnetic head assembly according to claim 3, wherein the magnetic body is formed by laminating magnetic bodies made of the same material or different materials. 6. The magnetic head assembly according to claim 3, wherein the conductors are formed by laminating conductors made of the same material or different materials.