JPH07192420A - Magnetic head assembly and magnetic disk device using the magnetic head assembly - Google Patents

Abstract

PURPOSE:To provide a magnetic head assembly capable of limiting deformation of a suspension generated when a mount is calked to be fixed. CONSTITUTION:Of a carriage 23 and a mount 28a to be calkingly fixed provided on one end of a suspension 27a, a thin part 36a is formed on a base around the root of a cylindrical part 35, and when calking and fixing are performed, only the cylindrical part 35 is displaced in the axial direction. Thus, when the mount 28a is calkingly fixed on a carriage 23, only the cylindrical part 35 is shifted in a direction for penetration of a calking steel ball, spreading of this displacement to the base part to which the suspension 27a is attached is limited and deformation of the suspension 27a generated by effect of this displacement is prevented.

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 having a mount connectable to a carriage by caulking and a magnetic disk drive using the magnetic head assembly.

[0002]

2. Description of the Related Art A magnetic disk device has a magnetic head assembly, and a read / write gap of a magnetic head incorporated in the magnetic head assembly
Record data on the set track on the magnetic disk
It is designed to be played.

A structure as shown in FIG. 5 is used for such a magnetic head assembly.

That is, the magnetic head assembly 1 is
The suspension 2 has a spring property and is made of a metal strip. A magnetic head 4 is attached to the tip of the suspension 2 via a gimbal 3, and a mount 5 is attached to the base. Reference numeral 4a represents a lead wire connected to the magnetic head 4 along the edge of the suspension 2.

In the magnetic disk device, as shown in FIGS. 6 and 7, a plurality of arms 7 projecting from the carriage 6 are assembled in such a manner that a magnetic disk (not shown) is sandwiched from both sides to form a magnetic head. The assembly 1 is swingably supported.

To assemble the magnetic head assembly 1 as described above, a through hole 8 is provided in the arm 7 and a mount 5 having a tubular portion 9 which can be inserted into the through hole 8 is used. An assembly is used in which the tubular portion 9 is caulked and fixed.

More specifically, as shown in FIG. 6, the cylindrical portions 9 of the mount 5 are respectively inserted from both sides of the through hole 8 of each arm 7 of the carriage 6, and as shown in FIG. −
The magnetic head assemblies 1 are arranged so as to face inward with respect to each other.

Then, the steel balls 10 for caulking, which are caulking parts, are press-fitted so as to penetrate through the inner cavities of the tubular portion 9 of the mount 5 arranged in series, whereby the mount 5 has a peripheral wall 9a of the tubular portion 9. Due to the deformation to the surroundings, the arm 7 is caulked and fixed.

By the way, the suspension 2 of the magnetic head assembly 1 is mounted by a predetermined amount on the plate surface of the magnetic disk (not shown) by mounting the magnetic head assembly 1 in the magnetic disk device via the carriage 6. It is arranged to bend. Then, due to the bending of the suspension 2 obtained, the magnetic head 4 is pressed against the plate surface of the magnetic disk (not shown) with a predetermined force.

The magnetic disk device utilizes this pressing to satisfactorily record and reproduce data from the magnetic disk.

That is, the magnetic head 4 uses the force of air generated by the rotation of the magnetic disk to suspend the suspension 2.
A small amount (0.05 to 0.1 μ) is levitated from the plate surface of the magnetic disk 4 against the pressing force of the magnetic disk 4 and passes through the read / write gap to the set track on the magnetic disk. The data is recorded / reproduced.

[0012]

By the way, the magnetic head 4 should be set to a load such that the pressing force of the suspension 2 provides a flying height that allows the best recording and reproduction of data.

However, the pressing force of the suspension 2 is
It is suspected that the magnetic head assembly 1 is caulked and fixed to the carriage 6 by a slight deformation.

That is, conventionally, the mount 5 projects the above-mentioned tubular portion 9 having the hole 12 through which the steel ball 10 can be inserted into the opening 11a of the rectangular base 11 having the circular opening 11a in the center. The installed structure is used. The base 11 is fixed to one plate surface portion of the suspension 2 by welding, and the tubular portion 9 penetrates the plate surface portion of the suspension 2 and projects to the other plate surface portion.

The magnetic head assembly 1 is attached to the carriage 6
At the time of assembling, the tubular portion 9 is inserted into the through hole 8 of each arm 7 as described above, and then the steel ball 10 is press-fitted so as to penetrate the inner cavity of the tubular portion 9 and caulked. However, during this caulking, the force acting on the mount 5 in the direction of pushing and expanding the tubular portion 9a as well as the force tending to displace the tubular portion 9a in the insertion direction (axial direction) of the steel ball 10 act.

Then, the base 11 of the mount 5 is bent by being displaced in the displacement direction as shown in FIG.

The base of the suspension 2 is attached to the base 11.

As a result, the suspension 2 is deformed according to the curve of the base 11, and the force for pressing the magnetic head 4 is changed.

However, the change in the pressing force of the magnetic head 4 changes the flying height of the magnetic head 4.

This is a slight deformation of the suspension 2 caused by caulking and fixing it to the mount 5, and the flying height of the magnetic head 4 varies, which influences the variation.
This causes a problem that the normal recording / reproducing of data by the magnetic head 4 is impaired.

The present invention has been made in view of such circumstances, and an object thereof is a magnetic head assembly and a magnetic head assembly capable of suppressing deformation of a suspension when a mount is caulked and fixed. An object is to provide a magnetic head device using the magnetic head assembly.

[0022]

In order to achieve the above object, a magnetic head assembly according to a first aspect of the present invention is such that a cylindrical portion is provided on a base portion around a root portion of the cylindrical portion constituting a mount. The flexible portion is formed so as to be displaceable in the direction.

According to a second aspect of the present invention, there is provided a magnetic disk device including the magnetic head assembly having the flexible portion according to the first aspect, a carriage for supporting the magnetic head assembly by caulking, and data through the magnetic head. And means for recording and reproducing.

[0024]

According to the magnetic head assembly of the first aspect of the present invention, when the carriage and the tubular portion are caulked and fixed, the axial displacement of the tubular portion caused when caulking and fixing the carriage is separated from the flexible portion. It occurs only on the side of the cylindrical portion, and does not spread to the base portion to which the suspension is attached.

That is, the deformation of the suspension at the time of caulking and fixing is avoided.

According to the magnetic disk device of the second aspect, the suspension is prevented from being deformed when the caulking is fixed, so that the magnetic disk device has a stable recording / reproducing performance.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in FIGS.

FIG. 1 shows the structure of, for example, a magnetic disk device to which the present invention is applied. In FIG.

On the right side of the housing 20, for example, three magnetic disks 21 are housed so as to overlap with each other at a predetermined interval in the vertical direction. These magnetic disks 2
The center of 1 is directly connected to a hub 22 of a spindle motor (not shown) mounted on the housing 20.
That is, the magnetic disk 21 is rotated at high speed by the spindle motor.

A rotatable carriage 23 is accommodated on the left side of the housing 20. This carriage 23
At the tip end side of each of the three magnetic disks 21, four strip-shaped arbores extending along the respective recording surfaces set on the front and back surfaces of the three magnetic disks 21 are provided.
A frame 24 is formed. As shown in FIG. 1, the arms 24 are arranged in parallel at predetermined intervals corresponding to the intervals of the magnetic disks 21. A through hole 25 is provided in the plate surface portion of each arm 24 on the tip side.

Each of these arms 24 is shown in FIGS.
As shown in FIG. 3, three downward magnetic head assemblies 26a facing the upper surface of the magnetic disk 21 and three upward magnetic head assemblies 26b facing the lower surface of the magnetic disk 21 are caulked and fixed. They are linked together.

That is, in the downward magnetic head assembly 26a, as shown in FIGS. 2 and 3, an upward mount 28a is provided on the plate surface portion of the base end portion of the strip plate-shaped suspension 27a, and the distal end portion is provided with The magnetic head 30a is supported downward via the gimbal 29a. The reference numeral 31a designates the magnetic head 30a to the suspension 27.
It is a lead wire extending along the right edge of a.

Further, the upward magnetic head assembly 2
6b is provided with a downward mount 28b on the plate surface portion on the proximal end side of the strip-shaped suspension 27b, and supports the magnetic head 30b upward on the distal end side via a gimbal 29b. It has the same structure as 26a. Reference numeral 31b is a lead wire extending from the magnetic head 30a along the right edge of the suspension 27b.

The mounts 28a and 28b each have an opening 32 in a rectangular base 32 having a circular opening 32a in the center.
The hole 3 into which the steel ball 33 as a caulking component can be inserted in a
It has a structure in which a cylindrical portion 35 having 4 is provided in a protruding manner. The base 32 is welded to each suspension 27.
a, 27b is fixed to one plate surface portion, and the tubular portion 35 penetrates the plate surface portions of the suspensions 27a and 27b.
It projects from the other plate surface.

An annular groove 36 is provided along the circumferential direction at the base portion around the root of each tubular portion 35 as shown in the enlarged view of FIG. The thin portion 36a (corresponding to a flexible portion) formed by the annular groove 36 makes the portion where the annular groove 36 is present weaker than the other portions and facilitates bending. As a result, when the steel balls 33 are press-fitted, the mounts 28a and 28b receive a force acting in the insertion direction, where the inner tubular portion 35 with the thin portion 36a as a boundary exists (a part α shown in FIG. 4). )
Only the axial displacement.

Then, each magnetic head assembly 26
a and 26b are similar to those described in the above-mentioned "Prior Art" section, from both sides of the through hole 25 of each arm 24 as shown in FIGS. 2 and 3, respectively. After inserting the tubular portion 35 and arranging the magnetic head assemblies 26a and 26b so as to face each other inward between the arms, the steel balls 33 are moved toward the inner cavities of the tubular portions 35 arranged in series. By the work of penetrating, they are respectively caulked and fixed to the arms 24 and connected to the carriage 23.

Reference numeral 38 is a lead wire 31 of each magnetic head 30a, 30b housed on the left side of the housing 20.
The control board is connected to a and 31b through a flat cable 39.

A voice coil motor 40 for swinging the carriage 23 is accommodated on the left side of the housing 20. The thrust generated by the voice coil motor 40 causes the magnetic heads 30a and 30b to oscillate between the innermost circumference and the outermost circumference of each magnetic disk 21, so that the data is recorded on the recording surface of each magnetic disk 21. -Recording of data and reproduction of the recorded data are possible.

According to the magnetic disk device thus constructed, the minute displacement that occurs when the magnetic head assemblies 26a and 26b are caulked and fixed to the carriage 23 as described in the above-mentioned "Prior Art" is caused. There is concern that it may affect the assemblies 26a and 26b, but this is not the case.

That is, the magnetic head assembly 26
When assembling a and 26b to the carriage 23, as shown in FIGS. 2 and 3, first, the cylindrical portions 35 of the mounts 28a and 28b are inserted from both sides of the through hole 25 of each arm 24, respectively. Then, the magnetic head assemblies 26a and 26b are arranged so as to face inward with respect to each arm.

After that, as shown in FIG. 3, the steel balls 33 for caulking are press-fitted so as to penetrate through the inner cavities of the cylindrical portions 35 arranged in series.

Here, since each tubular portion 35 is displaceable, the peripheral wall 35a of each tubular portion 35 is displaced in the expanding direction, and each tubular portion 35 is caulked to the suspensions 27a and 27b.

That is, since the steel ball 33 has a diameter slightly larger than the inner diameter of the hole portion 34 of each tubular portion 35, the peripheral wall 35a of the tubular portion 35 is inserted through the press fitting of the steel ball 33. The magnetic head assemblies 26a and 26b are deformed in the direction in which they penetrate into the inner surface of the hole 25, and the magnetic head assemblies 26a and 26b are fixed for each arm (caulking fixation).

At this time, a force that is generated when the steel ball 33 is press-fitted into the tubular portion 35 of each of the mounts 28a and 28b acts to shift it in the insertion direction (axial direction) of the steel ball 33, and An attempt is made to bend the base 32 of the mounts 28a and 28b.

Here, in the tubular portion 35, only the tubular portion 35 is axially displaceable by the thin portion 36a provided around the base of the tubular portion 35.

As a result, the axial deviation of each tubular portion 35 that occurs when the steel ball 33 is inserted through the tubular portion 35, as shown in the enlarged view of FIG. Almost only on the side of the shaped portion 35, the deformation due to the same displacement is limited to the portion α surrounded by the thin portion 36a.

That is, the deformation does not propagate to the base portion to which the suspensions 27a and 27b are attached.

As described above, this is the thin portion 36a.
By forming the above, the rigidity strength of the portion around the base of the tubular portion 35 is weakened, and only the tubular portion 35 has the suspension 27.
This is because they can be displaced in the axial direction independently of the base parts attached to a and 27b.

This means that the suspensions 27a, 2b when the mounts 28a, 28b are caulked and fixed.
The deformation of 7b is avoided.

As a result, the magnetic head assembly 26
When a and 26b are assembled in the magnetic disk device,
The magnetic heads 30a and 30b are pressed against the plate surface of the magnetic disk 21 with a stable predetermined pressing force.

Therefore, by adopting the magnetic head assemblies 26a and 26b having the thin portion 36a, variations in the flying height of the magnetic heads 30a and 30b are suppressed,
We can promise to record and reproduce normal data.

Further, such a magnetic head assembly 26
The magnetic disk device in which a and 26b are assembled is stable in the magnetic head 30 because it is not affected by caulking and fixing.
The read / write gaps of a and 30b are secured, and high recording / reproducing performance can be exhibited.

The same applies to crimping such as a method of pressing a pin, in addition to crimping with a steel ball.

Further, in the above-mentioned embodiment, the flexible portion is formed by providing the annular groove, but the invention is not limited to this.
Other structures may be used to displace only the tubular portion in the axial direction.

[0055]

As described above, according to the first aspect of the invention, it is possible to avoid the deformation of the suspension when the mount is caulked and fixed.

Therefore, the magnetic head can be pressed against the plate surface of the magnetic disk with a stable predetermined pressing force.

As a result, variations in the flying height of the magnetic head are suppressed, and normal recording / reproducing of data can be guaranteed.

According to the second aspect of the present invention, it is possible to realize a magnetic disk device capable of exhibiting stable recording / reproducing performance because a stable read / write gap of the magnetic head is secured.

[Brief description of drawings]

FIG. 1 is a perspective view showing a magnetic disk device incorporating a magnetic head assembly according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a magnetic head assembly together with a step of assembling it to a carriage.

FIG. 3 is a cross-sectional view for explaining a case where a magnetic head assembly assembled to the carriage is fixed by crimping with a steel ball for crimping.

FIG. 4 is a cross-sectional view showing the behavior of the magnetic head assembly shown by B in FIG. 3 during caulking and fixing.

FIG. 5 is a perspective view showing the entire magnetic head assembly.

FIG. 6 is a perspective view for explaining a process of assembling the magnetic head assembly to a carriage.

FIG. 7 is a cross-sectional view showing a case where the magnetic head assembly assembled to the carriage is fixed by crimping with a steel ball for crimping.

FIG. 8 is a cross-sectional view showing the behavior of the magnetic head assembly shown by A in FIG. 7 during caulking and fixing.

[Explanation of symbols]

21 ... Magnetic disk 23 ... Carriage 24 ... Arm 25 ... Through hole 26a, 26b ... Magnetic head assembly 27a, 27b ... Suspension 28a, 28b ... Mount 30a, 30b ... Magnetic head 32 ... Base 33 ... Caulking steel ball (Caulking part) 34 ... Hole 35 ... Cylindrical part 36a ... Thin part (flexible part)

Claims (2)

[Claims] 1. A strip-shaped suspension has a mount at one end thereof and a magnetic head at the other end thereof, the mount being a base attached to a plate surface portion of the suspension, A magnetic head assembly comprising: a cylindrical portion, which is provided on the base and penetrates a plate surface portion of the suspension and projects from a plate surface portion on the opposite side, and in which a caulking hole is formed. A magnetic head assembly characterized in that a flexible portion for allowing the tubular portion to be axially displaceable is formed in a base portion around a root portion of the tubular portion. 2. A magnetic disk and a mount at one end of a strip-shaped suspension, and a magnetic head facing the recording surface of the magnetic disk at the other end, and the mount comprises: The suspension has a base attached to a plate surface portion, and a caulking hole provided on the base plate for penetrating the plate surface portion of the suspension and projecting from a plate surface portion on the opposite side. A magnetic head assembly comprising a tubular portion and a flexible portion provided in a base portion around a root portion of the tubular portion and capable of axially displacing the tubular portion, and the magnetic head assembly. A magnetic disk device comprising: a carriage that supports a head assembly by caulking by inserting a caulking component into the cylindrical portion; and means for recording and reproducing data through the magnetic head.