JPH07169212A - Carriage driving voice-coil motor and magnetic disk device using the same - Google Patents

Abstract

PURPOSE:To prevent positional deviation of a stopper due to a mutual fitting error of magnetic yokes by connecting the magnetic yokes firm with a supporting rod between them in the carriage driving voice-coil motor. CONSTITUTION:Thrust required for oscillating a carriage is generated by the voice-coil motor 40 due to interaction of magnetic flux generated from a coil 22 and magnetic flux from a magnet 24 when the coil is energized by electricity. The stopper 42 for regulating a magnetic head in position possesses a tube 43 made of a synthetic resin and a fixing screw 44 as the supporting rod inserted into the tube 43. The fixing screw 44 has a head part larger than the outer diameter of the tube 43 and a screw shaft longer than the total length of the tube 43. Both end parts of the screw 44 are fixed to the side of the top magnet yoke 23 and the side of the bottom magnet yoke 29 respectively with screw stoppers. The whole tube is positioned and fixed between the yokes, connecting firm a part between the magnet yokes to be mounted with the stopper 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voice coil motor for driving a carriage and a magnetic disk device using the voice coil motor.

[0002]

2. Description of the Related Art In a magnetic disk device, a magnetic head moves relative to a recording surface of a magnetic disk to write data on a track set on the recording surface or read data recorded on the track. I am trying to do it.

To move the magnetic head, as shown in the internal view of the magnetic disk drive shown in FIG. 10 and the main portion shown in FIG. 11, a rotary carriage a is used to move the magnetic head. The magnetic head assembly c is mounted on the inner bottom surface of the housing d so as to be swingable.
Is used by a voice coil motor e incorporated in the housing d together with the carriage a.

In the figure, f is a magnetic disk installed in a housing d and rotated at high speed by a spindle motor (not shown), g is a magnetic head assembly c, and a magnetic head b is attached to the tip. It shows the suspension.

Such a boil coil motor e is shown in FIG.
And at the rear of the carriage a as shown in FIG.
It has a flat fan-shaped coil i which is supported so as to project using support rods h and h. On both sides of this coil i, a pair of pre-presses are placed so as to sandwich the coil i from above and below.
A toe-shaped top magnet yoke j and a bottom magnet yoke j are provided. The magnet yokes j, j are connected to each other. For example, top magnet yo
A fan-shaped magnet k that follows the movement trajectory of the coil i is provided on the inner surface of the groove j.

That is, in the boil coil motor e, when a current is applied to the coil i, a thrust force required to rotate the carriage a is generated. By the way, the voice coil motor e is usually provided with a stopper m for preventing the magnetic head b from coming off the outer peripheral edge of the magnetic disk f.
Is installed.

The stopper m has a structure in which a small-diameter soft tube tube n is used as a stopper part, and the tube tube n is mounted between the magnet yokes j and j. There is.

As shown in FIG. 12 and FIG. 13, this structure has the outermost position of the magnetic disk c in the turning locus of the carriage a among the plate surface portions of the magnet yokes j, j facing each other. Through holes o and o into which the tube tube n can be inserted, and the carriage a and the respective magnet yokes j and j are installed in the housing d, and then the top magnet yoke j is inserted. By pressing the tube tube n from the hole o into the through hole o of the other bottom magnet yoke j, the entire tube tube is magnet-yoke j, j.
It is installed between them.

By the way, conventionally, the magnet yoke is
As shown in FIGS. 12 and 13, the members j and j are joined together by fitting the concave and convex fitting portions p and q on the left and right sides.
After the magnets are positioned at predetermined positions, the magnet yokes j, j are connected by a screw r and assembled.

Specifically, the concave-convex fitting portion p on the left side is provided with a U-shaped concave portion s at the outer peripheral end of the top magnet yoke j.
At the outer peripheral edge of the bottom magnet yoke j corresponding to this,
It has a structure in which a bent leg u having a convex portion t at its tip is erected, and the yokes are positioned by mutual fitting (concave portion s and convex portion t).

The concavo-convex fitting portion q on the right side is provided with a truncated cone-shaped projection v on the inner surface of the top magnet yoke j and extends toward the projection v on the inner surface of the bottom magnet yoke j. A strut x having a truncated cone-shaped receiving portion w is provided at the tip end so that the yokes can be positioned by fitting each other (the protruding portion v and the receiving portion w). .

The entire projection v and the tip of the column x are hollow, and the screw r is screwed into the column x from the outside of the top magnet yoke j, whereby the "concave s and the protrusion" are formed. The magnet yokes j, j positioned by the section "t" and the "projection v and the receiving section x" are fixed.

At the left end of the bottom magnet yoke j, a mounting leg y for screwing the yoke j is projected, and a housing d serving as a yoke mounting portion is provided from the mounting leg y. The bottom magnet yoke j is fixed to the housing d by screwing a screw z into the inner bottom surface of the housing.

[0014]

By the way, as is known, the magnet yokes j, j have the entire outer shape including the concave and convex fitting portions p, q formed by press working. The stopper-m installed for this pressing
Have the possibility of misalignment.

That is, when the magnet yoke j is processed by press working, there is a limit to the high accuracy of the processing. High accuracy cannot be expected even in the concave portion s, the convex portion t, the protruding portion v, and the receiving portion w.

Due to this displacement, the gap between the concave portion s and the convex portion t and the gap between the protruding portion v and the receiving portion w are left, and the two magnet yokes j and j are not displaced. Due to being fixed.

For this reason, the position of the stopper-m which should be positioned at a regular position is affected by the displacement (the size of the gap) between the yokes that occurs when the yokes are fixed to each other.
There is a risk of misalignment.

Moreover, the position of the stopper m is a deviation between the yokes caused by external force such as vibration or shock from the outside even after the magnet yokes j, j are installed on the honing d. There is also a risk of misalignment.

Therefore, conventionally, in the magnetic disk f, the data area is designed in consideration of such an error in the mounting position of the stopper m. However, although this certainly prevents the influence of the positional deviation between the yokes,
The outermost circumference of the data area must be set in the area inside the magnetic disk f by the amount of the error in the mounting position of the stopper m.

Therefore, there is a problem that the data area of the magnetic disk f becomes small. Moreover, even if the stopper position is taken into consideration, in order to secure a data area as large as possible, when the positional displacement becomes worst due to external force such as vibration or shock, the outermost peripheral data of the magnetic disk f is
There is a problem that you cannot read or write data.

The present invention has been made in view of the above circumstances, and an object thereof is a voice coil motor for driving a carriage, which prevents displacement of a stopper, and a magnet using the voice coil motor. To provide a disk device.

[0022]

In order to achieve the above object, a voice coil motor for driving a carriage according to claim 1 is provided with a stopper for regulating the carriage position.
With a support rod having a tube-shaped stopper component installed on the exterior, and this support rod is inserted between the yokes in the direction in which the magnet yokes overlap, and one end of this support rod is inserted. Positioning and fixing to one side of the magnet yoke, positioning and fixing the other end to the other side of the magnet yoke, and
This is because the parts were placed between the magnet yokes.

In a voice coil motor for driving a carriage according to a second aspect of the present invention, the support rod according to the first aspect of the present invention is passed through one magnet yoke to the other magnet yoke so that the fixing work is easy. It consists of a fixing screw that is screwed into the installation part.

A magnetic disk drive according to a third aspect is
In order to provide a magnetic disk device in which the problem due to the stopper displacement is eliminated, the magnetic disk device is provided with the boil coil motor having the stopper described in claim 1.

According to a fourth aspect of the present invention, there is provided a voice coil motor for driving a carriage, wherein a stopper for restricting a carriage position is fixed to one magnet yoke and rises from the inner surface of the magnet yoke, and a tip portion of the other magnet is used. It consists of a rod-shaped stopper part that extends from the yoke to the evacuation point.

In a voice coil motor for driving a carriage according to a fifth aspect of the present invention, the stopper component according to the fourth aspect of the present invention is provided with one end protruding from the inner surface of one magnet yoke so that the fixing work is simple. The structure was fixed by pressing into the part.

A magnetic disk drive according to a sixth aspect of the present invention is
In order to provide a magnetic disk device in which the problem due to the stopper displacement is solved, a magnetic disk device provided with a boil coil motor having a stopper according to claim 4 is provided.

[0028]

According to the voice coil motor for driving a carriage described in claim 1, the rigidity of the support rod allows the magnet yoke to move.
Suppress the positional displacement of the stopper due to mutual mounting error.

Therefore, when setting the data area of the magnetic disk, the mounting error of the magnet yoke to be taken into consideration can be considerably reduced. Moreover, since the support bar firmly connects the magnet yokes to which the stoppers are attached, the displacement of the stoppers due to an external force can also be prevented.

According to the voice coil motor for driving a carriage of claim 2, the fixing screw is simply screwed from one magnet yoke through the other magnet yoke toward the yoke installation portion. -Bump-shaped stopper-
It is possible to fix the parts to each other.

According to the magnetic disk drive of the third aspect, since the problem due to the displacement of the stopper is solved as described in the first aspect of the invention, the magnetic disk in which the data area of the magnetic disk is increased accordingly. It is possible to provide a disk device.

Moreover, it also serves as a magnetic disk device having excellent impact resistance. According to the voice coil motor for driving a carriage described in claim 4, since the stopper component is fixed to only one of the pair of magnet yokes, the influence of the mounting error generated between the magnet yokes is prevented.
It will not appear as a misregistration.

As a result, similarly to the first aspect, when setting the data area of the magnetic disk, it is not necessary to consider the positional deviation of the stopper component due to the mounting error of the magnet yoke, and the voice coil motor Even if an external force such as vibration or shock is applied from the outside, the position shift will not occur.

According to the voice coil motor for driving a carriage described in claim 5, it is possible to take measures against the positional displacement only by press-fitting one end portion of the stopper component into the support portion of one magnet yoke.

According to the magnetic disk drive of the sixth aspect, the problem due to the displacement of the stopper as described in the fourth aspect is solved, and accordingly, the magnetic area of the magnetic disk in which the data area is increased accordingly. It is possible to provide a disk device. Moreover, it also serves as a magnetic disk device having excellent impact resistance.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the first embodiment shown in FIGS. FIG. 1 shows the configuration of, for example, a magnetic disk device to which the present invention is applied, in which 1 is a protective case.

The protective case 1 comprises a housing 2 whose upper surface is open and a top cover 3 which closes the opening of the housing 2. The housing 2 and the top cover-3 are fixed by a fixing screw 4.

On the left side of the housing 2, a plurality of sheets,
For example, three magnetic disks 5 are housed so as to overlap with each other at a predetermined interval in the vertical direction. The centers of these magnetic disks 5 are directly connected to a hub 6 of a spindle motor (not shown) mounted on the housing 2.
That is, the magnetic disk 5 is rotated at a high speed by the spindle motor.

A rotatable carriage 7 is housed on the right side of the housing 2. As shown in FIG. 2, the carriage 7 has a cylindrical main body portion 8 rotatably supported on the inner bottom surface of the housing 2.

That is, a bearing portion (not shown) is built in the main body portion 8, and the carriage 5 is rotatably supported with the pivot 9 as a fulcrum. The pivot 9 is rotatably supported by a screw 10a (only shown in FIG. 3) screwed from below the housing 2 and a screw 10b screwed through the top cover-3.

On the tip side of the carriage 5, the main body 8
From this, four strip-plate-shaped arms 11 extending along the respective recording surfaces set on the front and back surfaces of each of the three magnetic disks 5 are formed. The arms 11 are arranged in parallel at predetermined intervals corresponding to the intervals of the magnetic disks 5.

As shown in FIG. 2, each of the arms 11 faces the upper surface of the magnetic disk 5, three downward magnetic head assemblies 12a, and three magnetic head assemblies 12a facing the lower surface of the magnetic disk 5. And the magnetic head assembly 12b for upward facing are respectively connected by caulking and fixing.

Downward magnetic head assembly 12a
Is provided with an upward mount 14a, which is caulked and fixed to the lower surface of the arm, on the plate surface portion of the base end portion of the strip plate-shaped suspension 13a, and at the tip end portion through a gimbal 15a,
The magnetic head 16a is supported downward.

Upward magnetic head assembly 12b
Is provided with a downward mount 14b which is caulked and fixed to the upper surface of the arm on the plate surface portion on the base end side of the strip plate-shaped suspension 13b, and on the tip end side via a gimbal 15b,
The magnetic head 16b is supported upward.

Lead wires (not shown) extending from the magnetic heads 11a and 11b are connected via a flat cable 17 to a control circuit board 18 housed on the right side of the housing 2.

On the right side of the housing 2, a voice coil motor 21 for swinging the carriage 7 is housed. 3 and 4 show the detailed structure of the voice coil motor 21.

Explaining the voice coil motor 21, reference numeral 22 is a flat coil wound in a fan shape. The coil 22 includes a pair of left and right support rods 19, 19 protruding rearward from the main body 8 of the carriage 7.
Supported by. The coil 22 is held in parallel with the bottom wall 2 a of the housing 2 by being supported by the support rods 19, 19. That is, the coil 22 is swingably displaced about the pivot 9 of the carriage 7.

A plate-shaped top magnet yoke 23 is arranged close to the coil 22 on the side of the top cover 3 which sandwiches the coil 22. The top magnet yoke 23 extends in a substantially fan shape, following the swing range of the coil 22. A fan-shaped magnet 24 (permanent magnet) is attached to the inner surface of the top magnet yoke 23 along the swing range of the coil 22.

At the left end of the fan-shaped top magnet yoke 23, a projecting piece 26 having a U-shaped recess 25 at its tip is projected. A small through hole 27 is formed in a yoke portion corresponding to the outermost disk position of the carriage 7 on the rear side of the protruding piece portion 26.

On the inner surface of the right side portion of the top magnet yoke 23, a hollow truncated cone-shaped projection 28 is provided. On the bottom wall 2a side of the housing 2 with the coil 22 sandwiched therebetween, a plate-shaped bottom magnet yoke 29 that is paired with the top magnet yoke 23 is arranged. This bottom magnet yoke 29 also extends in a substantially fan shape, following the swing range of the coil 22.

At the left end of the bottom magnet yoke 29 corresponding to the projecting piece 26, a substantially L-shaped bent leg 30 that rises toward the tip of the projecting piece 26 is formed. The bent leg 30 is in the shape of a strip plate, and a convex portion 31 that can be fitted into the concave portion 25 is formed at the tip.

The concave portion 25 and the convex portion 31 form a concave and convex fitting portion 32 on one side for positioning the yokes.
Further, on the left side of the bottom magnet yoke 29, a mounting leg 33 projects from a position adjacent to the bending leg 30.
A through hole 34 for mounting is formed in the mounting leg 33.

From this through hole 34, a mounting screw 35 is screwed into a screw hole 36 provided on the inner bottom surface of the housing 2, and the bottom magnet yoke 29 serves as a yoke installation portion of the housing 2. Fix it on the bottom.

At the yoke portion corresponding to the through hole 27,
A through hole 37 having the same size as the through hole 27 is formed. Further, the top magnet yoke 23 corresponding to the above-mentioned protrusion 28
On the inner surface portion on the right side of the columnar columnar column 38 is projected. A frusto-conical receiving portion 39 capable of fitting with the protrusion 28 is formed at the tip of the column 38.

The receiving portion 39 and the projecting portion 28 form a concave-convex fitting portion 40 on the other side for positioning the yokes relative to each other. That is, the fitting between the concave portion 25 and the convex portion 31, the protrusion 28
The top magnet yoke 23 and the bottom magnet yoke 29 can be positioned relative to each other by fitting of the bottom magnet yoke 29 and the receiving portion 39.

Further, the screw hole 3 is provided at the center of the tip of the column 38.
8a is formed, and by screwing a screw 41 from the outside of the top magnet yoke 23 through the inner cavity of the protrusion 29 toward the screw hole 38a of the support column 38,
The magnet yokes 23 and 29 positioned by the "recessed portion 25 and the convex portion 31" and the "protruded portion 28 and the receiving portion 39" are fixed.

These assembled top magnet yokes 2
3, a magnetic circuit is formed around the coil 20 by the bottom magnet yoke 29, the protruding piece portion 26 serving as the side yoke, the bent leg 30, the protruding portion 28, and the support column 38.

That is, in the voice coil motor 40, when the coil 22 is energized, the interaction between the magnetic flux generated from the coil 22 and the magnetic flux from the magnet 24 generates the thrust required to swing the carriage 7. It has become.

As a result, the magnetic head 1 is
6a and 16b swing between the innermost circumference and the outermost circumference of each magnetic disk 5, and through the magnetic heads 16a and 16b,
It becomes possible to record data on the recording surface of each magnetic disk 5 and reproduce the recorded data.

Further, a stopper 42 for restricting the outermost peripheral positions of the magnetic heads 16a and 16b is mounted between the through hole 27 and the through hole 37 which face each other. The stopper-42 will be described.
Is a small diameter soft (synthetic resin) as a stopper part having an outer diameter that can be inserted into the through holes 27 and 37 and having a length corresponding to the distance between the through holes 27 and 37. It has a tube tube 43 and a fixing screw 44 as a support rod inserted into the tube tube 43.

The fixing screw 44 has a head portion 44a larger than the outer diameter of the tube pipe 43 and a screw shaft 44b longer than the entire length of the tube pipe 43. A fixing screw 44 having the tube tube 43 as an exterior is screwed into the screw hole 2b provided on the inner bottom surface of the housing 2 which is the yoke installation portion from the upper through hole 27 through the lower through hole 37. Has been done. Specifically, the head 44a of the fixing screw 44 is the top magnet yoke 2
It is screwed in until it comes into contact with the upper surface of 3.

By this screwing, both ends of the fixing screw 44 extending along the yoke are fixed to the top magnet yoke 23 side and the top magnet yoke 29, respectively, and the entire tube tube is fixed. Yaw including through holes 27 and 37
At the same time as positioning and fixing between the
The parts between the two magnet yokes are firmly connected.

The assembled tube tube 43 regulates the outermost peripheral position of the disk of the carriage 7. The column 38 serves as a stopper that regulates the innermost disc position of the carriage 7, and the swing range of the carriage 7 is regulated by both stoppers.

Reference numeral 45 is a circuit board for controlling the operation of the magnetic head assemblies 12a and 12b installed on the lower surface of the housing 2. When installing the voice coil motor 21 in such a magnetic disk device, the bottom magnet yoke 29 is first placed at a predetermined position on the inner bottom surface of the housing 2 in which the magnetic disk 5 has been assembled.
Screw on.

Next, the magnetic head assembly 12a,
The carriage 7 with the coil 12b and the coil 22 is rotatably installed at a predetermined position on the adduction surface of the housing 2 by using the screw 10a. Then, the tip (magnetic head 16a, 16b) of each magnetic head assembly 12a, 12b is placed on the recording surface of each magnetic disk 5 using a jig (not shown).

By this work, the coil 22 is connected to the through hole 3
It is arranged in the yoke portion between 7 and the column 38. After that, the top magnet yoke 23 is assembled into the bottom magnet yoke 29.

This is because the concave portion 25 is fitted into the convex portion 31,
This is done by assembling the top magnet yoke 23 with the bottom magnet yoke 29 while fitting the protrusion 28 into the receiving portion 39.

At this time, the top magnet yoke 23,
Both of the bottom magnet yokes 29 are formed by press work that is difficult to ensure accuracy, and the top magnet yoke 23 is attracted by the attached magnet 24. They are positioned relative to each other in a state in which a shift easily occurs.

After that, the screw 41 is screwed from above into the screw hole 38a of the support column 38. As a result, one side of the magnetic circuit is fixed. Further, the fixing screw 44 into which the tube pipe 43 has been inserted is screwed from the through hole 27 toward the screw hole 2a on the inner bottom surface of the housing 2. This screw insertion
The head 44a of the fixing screw 44 is the top magnet yoke 2
When it is carried out until it abuts the upper surface of 3, the upper and lower ends of the fixing screw 44 are fixed between the yokes, respectively, and the mounting of the stopper 42 is completed.

As a result, as shown in FIG.
The entire tube 43 is positioned between the top magnet yoke 23 and the bottom magnet yoke 29. With the fixing screw 44 of the voice coil motor 23 thus configured, the mounting error between the yokes at the portion where the stopper 42 is mounted is prevented.

That is, the top magnet yoke 23 and the bottom magnet yoke 29 assembled as described above are both formed by press working that is difficult to ensure accuracy, and further, the top magnet yoke. Since the attached magnet 24 gives an attractive force to the magnet 23, there is a possibility that the stopper 23 may be fixed while being displaced in the position where the stopper 42 is attached.

As a countermeasure against this, the portions of the yokes to which the stoppers 42 are attached are positioned and fixed by the fixing screws 44 penetrating the yokes as described above. This is due to the rigidity of the fixing screw 44.
The parts where the yokes are mounted are fixed to each other at predetermined positions so that there is no displacement.

Therefore, the mounting error at the same portion is reduced by the fixing screw 44, and the shift of the stopper position due to the mounting error between the magnet yokes is significantly suppressed.

Therefore, when setting the data area of the magnetic disk 5, the magnet yokes 23 and 2 to be taken into consideration.
Installation error of 9 is quite small. This contributes to an increase in the data area of the magnetic disk 5 and brings about an effect that a magnetic disk device having a large storage capacity can be provided.

Moreover, the fixing screw 44 is fixed to the stopper-42.
Since the magnet yokes attached to are firmly connected to each other, displacement is unlikely to occur even if external force such as vibration or shock is applied. That is, displacement of the stopper 42 due to external force is also prevented.

This brings about an effect that a magnetic disk drive having high impact resistance can be provided. 5 to 7
Shows a second embodiment of the present invention.

In the second embodiment, the rigidity of the fixing screw 44 in the first embodiment regulates the yokes so as not to cause a positional deviation, whereas in the second embodiment, the mounting error caused by the yokes is suppressed. The position shift of the stopper 42 is eliminated by not affecting the position of the stopper 42.

That is, in this embodiment, the stopper 42 is fixed to only one side of the magnet yoke 23, 29. Specifically, as a mounting structure of the stopper 42, as shown in FIGS. 5 to 7, instead of the through hole 37 of the bottom magnet yoke 29, a tube tube is provided on the inner surface of the yoke 29. A bottomed cylindrical support portion 50 into which 43 can be press-fitted
To project. In addition, a tube tube 43 that serves as a stopper part
Is the bottom length of the support 50 and the top magnet yo
A tube tube is used that is shorter than the distance between the tube 23 and the inner surface thereof.

The tube tube 43 is a bottom magnet yo-yo.
After installing the yoke 29, one end is press-fitted into the inner cavity of the support portion 50 to rise from the inner surface of the bottom magnet yoke 29, and then the top magnet yoke 23 is placed on the bottom magnet yoke 29. It is placed between the yokes by incorporating it.

As a result, the tube tube 43 is fixed to the inner surface of the bottom magnet yoke 29 with its tip extending only to the point where it is retracted from the inner surface of the top magnet yoke 23.

In this stopper structure, since the tube tube 43 is fixed to only one of the magnet yokes 23 and 29, the effect of mounting error between the yokes is affected by the position of the stopper 42. Does not appear as a gap.

This means that when the data area of the magnetic disk 5 is set, it is not necessary to consider the positional deviation of the stopper 42 due to the mounting error of the magnet yoke, and the vibration and shock from the outside of the voice coil motor 21. Even if an external force such as is applied, the position shift will not occur,
The same effect as the first embodiment is obtained.

In the second embodiment, the structure of the magnetic disk device is the same as that of the magnetic disk device of FIG. 1 described in the first embodiment except for the voice coil motor 21, which is the main part. The drawings showing the configuration and the description thereof are omitted.

FIG. 8 shows a third embodiment of the present invention. This embodiment is a modification of the second embodiment described above, and is not press-fitted,
The tube tube 43 is fixed to only one of the magnet yokes 23 and 29 by using a fixing screw 57.

Specifically, the structure is not a support portion 50 having a hole for press-fitting but a support portion 56 having a screw hole 55, and the tube pipe 43 is provided in the screw hole 55 of the support portion 56. The tube pipe 43 is positioned and fixed between the yokes by screwing a fixing screw 57, which has an overall length shortened in accordance with the tube pipe 43, which is externally mounted.

Even in this case, the same effect can be obtained.
In the above-mentioned second and third embodiments, the bottom magnet yoke 29 was installed, and then the tube tube 43 was press-fitted and fixed by screwing. However, as shown in FIG. A cutout portion 23a is provided at a position of the top magnet yoke 29 corresponding to the position, the top magnet yoke 29 is assembled to the bottom magnet yoke 29, and then the tube pipe 43 is cut from the cutout portion 23a. The support 55
Alternatively, the tube tube 43 may be positioned and fixed between the yokes by press-fitting it toward the base plate or by screwing the fixing screw 57 into the support portion 56.

By doing so, the assemblability of the voice coil motor is improved. In this case, the tube tube 43 may have a length such that one end thereof projects above the top magnet yoke 29. That is, since the top magnet yoke 29 is provided with the notch 23a, the top magnet yoke 29 and the notch 23a do not come into contact with each other. Therefore, the displacement of the top magnet yoke 29 does not affect the tube tube 32. Further, the same effect can be obtained by providing the top magnet yoke 29 with a through hole instead of the notch 23a. In this case, it is necessary that the diameter of the through hole is sufficiently larger than the diameter of the tube tube 43.

In the second and third embodiments,
Although the tube tube 43 is installed on the bottom magnet yoke 29 side, it may be installed on the top magnet yoke 23 side.

[0089]

As described above, the first and fourth aspects are provided.
According to the invention described in (1), the carriage driving voice coil model is capable of preventing the stopper from being displaced due to an external force such as displacement of the stopper, vibration, impact, etc. caused by mutual mounting error of the magnet yokes. -It can be realized.

According to the second and fifth aspects of the present invention, in addition to the above, it is possible to realize a voice coil motor for driving a carriage in which fixing work of the stopper is simple. According to the invention described in claims 3 and 6, the stopper-
By preventing the displacement of the magnetic disk, it is possible to realize a magnetic disk device having a high storage capacity and a high impact resistance.

[Brief description of drawings]

FIG. 1 is a perspective view showing a voice coil motor for driving a carriage according to a first embodiment of the present invention together with a magnetic disk device incorporating the voice coil motor.

FIG. 2 is an enlarged perspective view showing a voice coil motor for driving the carriage.

FIG. 3 is an exploded perspective view of the same voice coil motor for driving the carriage.

4 is a sectional view of the voice coil motor taken along the line AA in FIG.

FIG. 5 is a perspective view showing a voice coil motor for driving a carriage according to a second embodiment of the present invention.

FIG. 6 is an exploded perspective view of the voice coil motor for driving the carriage.

7 is a sectional view of the voice coil motor taken along the line AA in FIG.

FIG. 8 is a sectional view showing an essential part of a voice coil motor for driving a carriage according to a third embodiment of the present invention.

FIG. 9 is a perspective view showing a modification of the second embodiment.

FIG. 10 is a perspective view showing an internal configuration of a magnetic disk device.

FIG. 11 is an enlarged perspective view showing a voice coil motor for driving the carriage.

FIG. 12 is an exploded perspective view of the same voice coil motor for driving the carriage.

FIG. 13 is a voice coil motor along line CC in FIG.
FIG.

[Explanation of symbols]

5 ... Magnetic disk 7 ... Carriage 12a, 12b ... Magnetic head assembly 21 ... Voice coil motor 22 ... Coil 23, 29 ... Magnet yoke 24 ... Magnet 32, 40 ... Concavo-convex fitting part 42 ... Stopper 43 ... Tube Pipes 44, 57 ... Fixing screws (supporting rods) 50, 56 ... Supporting parts

Claims (6)

[Claims] 1. A pair of plate-shaped magnet yokes are assembled and positioned by a concave-convex fitting at predetermined positions sandwiching a coil attached to a rotary carriage, and between the magnet yokes. In a boil coil motor equipped with a stopper for restricting the magnetic head from coming off from the outer peripheral edge of the magnetic disk, the stopper has a support rod on which a tube-shaped stopper component is mounted, The support rod is inserted between the yokes in the direction in which the magnet yokes overlap, one end of the support shaft is positioned and fixed to one side of the magnet yoke, and the other end of the support shaft is attached to the magnet yoke. A carriage driving boil coil mower characterized in that it is positioned and fixed to the other side and the stopper part is arranged between the magnet yokes.
Ta. 2. The carriage drive according to claim 1, wherein the support bar is a fixing screw that is screwed from one magnet yoke through the other magnet yoke into the yoke mounting portion. Boil coil motor for. 3. A magnetic disk and a magnetic head assembly for recording and reproducing data from the magnetic disk,
A carriage with a coil for supporting the magnetic head assembly and a voice coil motor for driving the carriage are provided, and the voice coil motor is assembled by concave-convex fitting so as to sandwich the coil of the carriage at a predetermined position. It has a pair of plate-shaped magnet yokes positioned at the center and a support rod provided between these magnet yokes and fitted with a tube-shaped stopper component. The magnet yokes are inserted between the yokes in the overlapping direction so that one end of the support rod is positioned and fixed on one side of the magnet yoke, and the other end is positioned and fixed on the other side of the magnet yoke. And a stopper formed by disposing the stopper component between the magnet yokes. 4. A pair of plate-shaped magnet yokes are assembled and positioned by a concavo-convex fitting at predetermined positions sandwiching a coil attached to a rotary carriage, and between the magnet yokes. In a boil coil motor equipped with a stopper for restricting the magnetic head from coming off the outer peripheral edge of the magnetic disk, the stopper is fixed to the one magnet yoke and rises from the inner surface of the magnet yoke. A carriage driving boil coil motor characterized in that a portion thereof comprises a rod-shaped stopper component extending from the other magnet yoke to a retracted position. 5. The rod-shaped stopper component according to claim 4, wherein one end portion is press-fitted and fixed to a support portion projecting on an inner surface of one of the magnet yokes. Boil coil motor for driving carriage. 6. A magnetic disk and a magnetic head assembly for recording and reproducing data from the magnetic disk,
A carriage with a coil for supporting the magnetic head assembly and a voice coil motor for driving the carriage are provided, and the voice coil motor is assembled by concave-convex fitting so as to sandwich the coil of the carriage at a predetermined position. A pair of plate-shaped magnet yokes that are positioned in the vertical direction, and fixed to the one magnet yoke provided between the magnet yokes and rising from the inner surface thereof, and the tip portion of the other magnet yoke. -A magnetic disk drive comprising: a rod-shaped stopper extending from the recess to a retreat point; and a stopper made of a component.