JPH10106181A - Rotary head device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize balance adjustment related to a turning type head device without complicating constitution and remarkably raising cost. SOLUTION: This rotary head device is provided with a head for reproducing and/or recording for a disk like recording medium and a positioning member 4 supporting the head and positioning the head for the recording medium by rotating it around a prescribed axis. For adjusting the balance of the positioning member 4, a massive substance 9 (e.g. ultraviolet rays curing type resin, etc.,) is stuck to the prescribed part (recessed part, etc.,) of the positioning member 4, or the massive substance is fixed to the positioning member 4 after a prescribed directional position is adjusted and the massive substance is selected in the positioning member 4. Thus, the centroid of the positioning member 4 is almost matched with the rotational center.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head device for reproducing and / or recording data on a disk-shaped recording medium and a method of manufacturing the same, such as a magnetic disk and an optical disk. It is an object of the present invention to improve the impact resistance of a positioning mechanism including a head in an apparatus using a rotating disk.

[0002]

2. Description of the Related Art In a disk storage device (for example, represented by a hard disk drive) using a disk-shaped recording medium, information is read from and written to a rotating means of the recording medium and the recording medium. And a positioning mechanism including a positioning member for positioning the recording medium by rotating the head about a predetermined axis. At the time of recording / reproducing on the recording medium, a predetermined rotating force (for example, an electromagnetic force generated by using a coil, a magnet, or the like) is applied to the positioning member, whereby the head is moved in a predetermined rotation range. It is configured to be moved.

[0003]

As for the rotational movement of the positioning member, it is ideally desirable that the center of rotation and the center of gravity coincide with each other. There is a problem that it is difficult to realize such an ideal state.

Therefore, a mechanism for adjusting the position of the rotation center axis is provided for the positioning member, and the center of gravity of the positioning member is positioned on or near the axis by moving the rotation center axis. A method of adjusting the balance of the positioning member in such a manner can be considered.

[0005] However, in such a method, there is a possibility that the configuration of the positioning mechanism is complicated or the cost is increased.

SUMMARY OF THE INVENTION It is an object of the present invention to achieve balance adjustment of a positioning member in a rotary head device without complicating the configuration of a head positioning mechanism and significantly increasing costs.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a positioning member is fixed to a predetermined portion or a mass object fixed after adjusting the position or selecting a mass is positioned on the positioning member. And the center of gravity of the positioning member substantially coincides with the center of rotation of the positioning member.

Therefore, according to the present invention, by fixing the mass to a predetermined position or adjusting the position or fixing after selecting the mass,
The balance of the positioning member can be adjusted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary head device 1 according to the present invention.
As shown in FIG. 1, a head 3 for reproducing and / or recording on a disk-shaped recording medium 2 is supported, and the head 3 is supported and rotated around a predetermined axis. And a positioning member 4 for positioning the head with respect to the recording medium.

The recording medium 2 is rotated by a rotating means 5 and includes a medium used for reading and / or writing recorded information, and includes, for example, a magnetic disk and a magneto-optical disk. And the like.

The positioning member 4 constitutes a part of the positioning mechanism 6. In the present invention, a mass fixed to a predetermined portion of the positioning member or fixed after position adjustment or mass selection is used for balance adjustment of the positioning member 4. It is provided for.

FIG. 2 is a diagram for explaining the definition of various quantities relating to the positioning member.

In FIG. 1, the center axis of rotation of the positioning member 4 is selected as the Z axis, and the axis extending in the longitudinal direction through the center of rotation of the positioning member 4 is defined as the X axis. When a three-dimensional orthogonal coordinate system with the Y axis is set, the “unbalance amount” of the positioning member 4 is defined as the distance between the center of gravity of the positioning member and the center of rotation and the mass of the positioning member (referred to as “m”). ), And is defined as a vector amount obtained by multiplying the position vector of the center of gravity with respect to the rotation center of the positioning member by the mass m.

A point G in the figure indicates the center of gravity of the positioning member 4, and its position coordinate value is (rx, ry), the position vector of the center of gravity G is rg = (rx, ry), and the unbalance amount is a vector. When “ub” is set, ub is expressed as “ub = m ·
rg = (m · rx, m · ry) ”(hereinafter, m
Rx = mrx, m · ry = mry. ).

The rotation angle of the positioning member 4 about the Z axis is “θ”, the moment of inertia of the positioning member 4 about the Z axis is “Izz”, and the acceleration given to the positioning member 4 is a vector “a = (ax, ay) ”, from the equation of motion for the rotational movement of the positioning member 4,“ θ ⁽²⁾
= (Ax · mry−ay · mrx) / Izz ”is obtained. Note that “θ ⁽²⁾ ” is the second derivative of the rotation angle θ with time,
In other words, it indicates the angular acceleration (hereinafter, “ ⁽ⁿ⁾ ” attached to the right shoulder of the variable indicates the n-th derivative with respect to time.) The left side of the above equation is obtained by calculating the moment of force by the cross product Is divided by the moment of inertia.

Therefore, when the angular acceleration and the acceleration are known, it is possible to determine the inertia moment Izz and determine the components mrx and mry of the unbalance amount ub.
For example, if a = (ax, 0), mry = Izz ·
mry is determined from θ ⁽²⁾ / ax, and ry is determined because the mass m is known. Similarly, a =
If (0, ay), mrx = −Izz · θ ⁽²⁾ / a
mrx is determined from y, and since the mass m is known, r
x will be obtained.

If the angular acceleration applied to the positioning member 4 becomes large, there is a possibility that the recorded information and the reproduced information may be adversely affected. For example, there is a high possibility that erroneous recording on an adjacent track or a read error is caused. Therefore, in order to prevent such an inconvenience, the above-described unbalance amount of the positioning member 4 is made close to zero, the positioning member 4 is made insensitive to disturbance acceleration, and the impact resistance is improved. There is a need.

As a method of adjusting the balance of the positioning member 4, a method of adjusting the mass of the positioning member to bring the amount of unbalance close to zero can be mentioned. In this method, the amount of unbalance is defined by the position of the center of gravity and the mass. This is a method of moving the position of the center of gravity by changing the mass distribution of the positioning member, and has an advantage that the balance of the positioning member can be adjusted with a relatively simple configuration.

The present invention adopts a structure in which a mass fixed to a predetermined portion of the positioning member or fixed after position adjustment and / or mass selection is provided for balance adjustment of the positioning member. The method is included below.

(A) A method for increasing or decreasing the mass of the positioning member. (B) A method for adjusting the position of a mass constituting the positioning member.

The method (a) includes a method of adjusting the balance by increasing the mass of the positioning member, and a method of adjusting the balance by decreasing the mass of the positioning member. Since the former method is more preferable in this respect, the former method is also used in the present invention, and the following method can be further mentioned.

(A-1) A method of fixing a mass that can be weighed and taken out arbitrarily to a positioning member. (A-2) An optimum one from a plurality of weights prepared in advance. A method of selecting and fixing to a positioning member.

First, as a method (a-1), a concave portion is formed at a predetermined position of the positioning member, and a curable fluid or a gel-like substance is injected into the concave portion in an amount corresponding to the imbalance amount. Examples of the method include drying (natural drying or forced drying) or curing by a predetermined external stimulus (for example, ultraviolet rays, X-rays, heat rays, or chemical substances).
According to this method, since a mass can be arbitrarily measured and fixed to the positioning member, high-precision balance adjustment is possible.

FIG. 3 conceptually shows the adjustment method. A quantity corresponding to the amount of unbalance is measured from the fluid or gel-like material 8 in the container 7 and is measured by the positioning member 4.
Is adhered by dropping to a concave portion 9 formed in advance, and this is fixed to the positioning member 4 by subsequent curing.
When the fluid or the gel-like material 8 is a self-curing resin, it may be left alone, but when it is necessary to positively cure the fluid or the gel-like material 8, a predetermined curing means is required. .

In the method (a-2), a weight or a combination of weights that minimizes the unbalance amount is selected from a plurality of weights prepared in advance to be added to the positioning member. Is fixed to the positioning member.

That is, as conceptually shown in FIG. 4, one or a plurality of weights which minimize the amount of unbalance is selected from the plurality of weights 10, 10,. In place. Note that this method has a limited selection range of mass and can perform only a stepwise balance adjustment as compared with the above method (a-1). However, it is necessary to suppress the variation in the manufacturing of the positioning member to a certain extent. When the adjustment range can be narrowed down by the adjustment, it is effective in simplifying the adjustment work and shortening the adjustment time.
In addition, as a method of fixing the weight 10, in addition to a method of providing a fixing mechanism using a screw or a holding member on the positioning member, when fixing the screw 10 itself as in the case of screwing when the screw 10 itself is used for the weight 10. A method that does not increase the mass is preferable, but various forms such as a method of externally supplying and fixing a resin, an adhesive, or the like are possible within an allowable range.

Next, in the above method (b), a mass member whose distance from the center of rotation of the positioning member is adjustable is attached to the positioning member, and the mass is displaced according to the unbalance amount. This is a method of moving at and then fixing at an optimal position.

That is, as conceptually shown in FIG. 5, the mass 11 attached to the positioning member 4 is moved in a predetermined direction to define its position.
1 is immobilized.

In this method, since the mass of the positioning member is not changed, there is no influence on the positioning performance due to the increase and decrease of the mass, and the balance adjustment is easier than the method (a). There are advantages. In addition, as a method of fixing the mass 11, a method in which the mass does not increase at the time of fixing such as a method in which a fixing mechanism using a screw or a holding member is provided on the positioning member is preferable, but if it is within an allowable range. A method of fixing by supplying adhesive etc. from the outside,
Various forms are possible.

With respect to the balance adjustment of the positioning member 4 described above, the recess 9 is used in the method (a-1).
Are arranged so that the centers of these recesses are located on two axes (for example, X axis and Y axis) orthogonal to each other on the XY plane when viewed from the Z axis direction. By injecting an appropriate amount of fluid or gel, the center of gravity of the positioning member can be moved in the XY plane.

Similarly, in the above method (a-2), two weights are prepared, and the weights are placed on the positioning member so that two axes passing through the center of gravity of each weight and the center of rotation of the positioning member are orthogonal to each other. Or method (b)
By providing two masses on the positioning member and defining the adjustment directions to be orthogonal to each other, the center of gravity of the positioning member can be moved in the XY plane.

It is also possible to adjust the balance of the positioning member only in one direction. For example, there is a method of adjusting only the axis (X-axis) extending in the longitudinal direction of the positioning member. Although this focuses on one component mrx of the unbalance amount of the positioning member and brings it closer to zero, this method obtains a certain degree of validity only because the components of the positioning member are substantially in the longitudinal direction. Since the positioning member is arranged along the direction, the displacement of the center of gravity in the width direction (Y-axis direction) of the positioning member is small, and the influence of an impact applied to the positioning member is mainly large in the longitudinal direction. Therefore, it is more important to reduce the value of mrx. In other words, this method is effective in terms of speeding up the calculation time, simplifying the device configuration, and shortening the adjustment time because the main part of the unbalance amount is adjusted by adjusting mrx to be close to zero. is there.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, first to fourth embodiments of the present invention will be described. In each embodiment, since the present invention is applied to a rotary head in a hard disk drive, first, a configuration of a hard disk drive and a head positioning mechanism will be briefly described with reference to FIGS.

FIG. 6 shows the structure of the hard disk drive device 12, in which a rotary actuator 14, a disk 15 as a recording medium and a rotating mechanism 16 thereof (including a spindle motor and a disk hub) are provided on a chassis 13 thereof. Is included). These are sealed by covering the chassis 13 with the cover 17.

FIG. 7 shows a rotary actuator 14, in which a positioner 18 for positioning a magnetic head (not shown) with respect to the disk 15 is rotated by a rotary support shaft 19 so that its center axis (in the figure). (Shown by the Z-Z axis).

The positioner 18 corresponds to the positioning member 4 described above, and the positioner 18
Suspension members 21, 21, head portions 22, 22,
A flexible board 24 for supplying power and transmitting signals is connected to the coil 23.

The arm portion 20 is formed of a metal material or the like. One end of the arm portion 20 in the longitudinal direction is formed by projecting so that the cross-sectional shape of a cut surface in a plane including the ZZ axis has a U-shape. Parts 20a, 20a are formed,
Suspension members 21 and 21 are separately fixed to a and 20a.

The suspension members 21, 21 are formed of a material having spring elasticity such as a leaf spring, and gradually taper toward the end opposite to the portion attached to the projections 20a, 20a. Head portions 22, 22 are fixed to the portions, respectively. Note that the suspension members 21 and 21 are
Is pressed against the disk 15 with a predetermined load.

At the end of the arm 20 opposite to the side to which the suspension members 21 are fixed, a coil 23 projecting in a C shape when viewed from the ZZ axis direction. Mounting portions 20b, 20b are provided,
The coils 23 wound in a substantially annular shape are attached to the mounting portions 20b and 20.
b and is attached to the arm unit 20 in a state of being sandwiched therebetween.

Lower yoke 25 fixed on chassis 13
A magnet 26 having a substantially fan shape is mounted on the chassis 13, and an upper yoke 27 is mounted on the chassis 13 in a state where the magnet 26 faces the magnet 26.

The coil 23 is located between the magnet 26 and the upper yoke 27. A magnetic circuit is formed by the lower yoke 25, the upper yoke 27, and the magnet 26. A force is generated in the direction indicated by. With this force, the positioner 18 is moved ZZ
By rotating about the axis, moving the head unit 22 to a desired position on the disk 15 and positioning the head with respect to an arbitrary track on the disk, it is possible to read and write signals. I have.

FIG. 8 shows a first embodiment of the present invention, and the above-mentioned method (a-1) is used as a balance adjusting method.
Is used, and as a mass material, an ultraviolet curable resin (hereinafter, referred to as
It is called "UV resin". ) Is used, an appropriate amount of UV resin is measured in accordance with the amount of imbalance, and then adhered to a predetermined portion of a positioner, and the resin is cured by irradiating ultraviolet rays.

As in FIG. 2, the center axis of rotation of the positioner 28 is selected as the Z axis, and the axis extending in the longitudinal direction through the center of rotation of the positioner 28 is defined as the X axis, and the axis is orthogonal to both axes. When a three-dimensional rectangular coordinate system with Y as the Y axis is set, the rotation support shaft 1 of the arm 20 of the positioner 28 is
Two concave portions 29x and 29y are formed at a position closer to 9 at an angular interval of 90 degrees around the Z axis, and the UV resin is fixed to these concave portions. That is, one concave portion 29x is provided to reduce one component mrx of the unbalance amount ub, and the center of the concave portion 29x is located on the X axis when viewed from the Z axis direction. The other concave portion 29y is provided to reduce the other component mry of the unbalance amount ub.
When viewed from the axial direction, the center of the concave portion 29y is located on the Y axis.

When the positioner 28 is divided into two parts on the YZ plane, the mass of the portion closer to the coil 23 is designed to be slightly smaller than the mass of the portion on the head portion 22 side. Is located closer to the head portion 22 than the YZ plane, and the center of gravity of the coil 2 is adjusted by injecting and curing UV resin in the recesses 29x and 29y.
It can be adjusted so as to be shifted closer to 3 or closer to the Y axis.

Since the X coordinate value and the Y coordinate value of the concave portions 29x and 29y are determined in advance, the concave portions 29x and 29y
It is possible to calculate how much amount of the UV resin is injected into each of the y positions so that the center of gravity of the positioner 18 can be positioned on or near the Z-axis. UV resin is supplied to the concave portions 29x and 29y by supply means (not shown).

FIG. 9 shows a second embodiment of the present invention, in which the X-axis direction component mrx of the unbalance amount of the positioner is obtained, and only the balance adjustment in the X-axis direction is performed. Note that the second embodiment differs from the first embodiment in many parts.
Therefore, the same parts as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and the description thereof will be omitted. It is to be noted that the method of assigning such reference numerals and omitting the description are the same in each embodiment described below.

In the second embodiment, since only the balance adjustment in the X-axis direction is performed by focusing on the fact that the displacement of the center of gravity of the positioner 28A in the Y-axis direction is relatively small, as shown in FIG. Only the concave portion 29x for adjusting the balance in the axial direction is provided, and an appropriate amount of UV resin is supplied only to the concave portion 29x.

Therefore, in this embodiment, the configuration can be simplified and the adjustment time can be shortened as compared with the first embodiment.

FIG. 10 shows a third embodiment, and employs the above-mentioned method (b) as a balance adjusting method.

That is, the resin material 3 is inserted into the coil hole 23a formed in the inner peripheral surface of the coil 23 in the positioner 28B.
0, and a long hole 31 extending along the X-axis direction is formed at the center of the resin material 30 as shown in the great circle of the figure, and the weight 32 is moved along the long hole 31 along the X-axis. It is engaged with the long hole 31 so as to be movable in the direction.

That is, in the present embodiment, only the balance adjustment of the positioner 28B in the X-axis direction is performed similarly to the second embodiment, and the weight 32 is moved along the X-axis to adjust the weight at the optimum position. By fixing, the adjustment is performed so that the X-axis direction component mrx of the unbalance amount becomes the minimum value. Note that the coil holes 23 are used as mounting spaces for the weights 32.
By using a, the space can be effectively used.

FIG. 11 shows a fourth embodiment, in which the above-mentioned method (a-2) is adopted as the balance adjusting method.

That is, the resin material 3 is inserted into the coil hole 23a formed in the inner peripheral surface of the coil 23 in the positioner 28C.
. Are arranged along the X-axis direction in the resin material 33, and a plurality of screw members 35, 35,. Screw together.

That is, in this embodiment, only the balance adjustment of the positioner in the X-axis direction is performed as in the second and third embodiments, and the screw members 35, 35,.
Is used as a weight, and the adjustment is performed by the combination of the screw member 35 and the screw hole 34 so that the X-axis direction component mrx of the unbalance amount becomes the minimum value. In addition, by filling the resin into the coil hole 23a and forming the screw hole 34 therein, the space can be effectively used.

[0055]

As is apparent from the above description, according to the first to third aspects of the present invention, the positioning of the mass by fixing the mass to a predetermined location or by adjusting the position or fixing after selecting the mass is performed. Since the balance of the members can be adjusted, the structure of the mechanism including the positioning member is not complicated, and the cost is not significantly increased.

According to the fourth aspect of the present invention, the balance is adjusted by injecting a curable fluid or a gel-like material into a predetermined portion of the positioning member in an amount corresponding to the unbalance amount. A high-precision balance adjustment is possible by arbitrarily weighing and fixing the gel-like material to the positioning member.

According to the fifth aspect of the invention, the mass whose distance from the center of rotation of the positioning member can be adjusted is
Since the mass is fixed after being moved by the displacement amount corresponding to the unbalance amount of the positioning member, the mass of the positioning member does not change, and therefore, the positioning performance due to the increase or decrease of the mass is reduced. There is no influence.

According to the sixth aspect of the present invention, the weight which can select the distance from the center of rotation of the positioning member in a stepwise manner is fixed to the positioning member, thereby simplifying the balance adjustment and reducing the adjustment time. Shortening can be achieved.

According to the seventh to ninth aspects of the present invention, the accuracy of adjustment can be improved by performing balance adjustment in a plane orthogonal to the rotation center axis of the positioning member.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a rotary head device.

FIG. 2 is an explanatory diagram of definitions of various quantities in a positioning member.

FIG. 3 is an explanatory diagram of a balance adjustment method using a mass capable of measuring an arbitrary mass.

FIG. 4 is an explanatory diagram of a balance adjustment method for selecting an optimum weight from a plurality of weights.

FIG. 5 is an explanatory diagram of a balance adjustment method for defining a position of a movable mass provided on a positioning member.

FIG. 6 is a diagram for explaining an embodiment of the present invention, together with FIGS. 7 to 11, and is a diagram showing a configuration of a hard disk drive device.

FIG. 7 is a diagram illustrating a configuration example of a positioning mechanism including a positioner.

FIG. 8 is a diagram showing a positioner according to the first embodiment.

FIG. 9 is a view showing a positioner according to a second embodiment.

FIG. 10 is a diagram showing a positioner according to a third embodiment.

FIG. 11 is a view showing a positioner according to a fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating head device, 2 ... Recording medium, 3 ... Head, 4
... Positioning member, 8 ... Fluid or gel, 9 ... Recess, 10 ... Weight, 11 ... Mass

Claims (9)

[Claims] 1. A head for playing back and / or recording on a disk-shaped recording medium, and supporting the head and rotating the head about a predetermined axis to rotate the head. A rotary head device having a positioning member for positioning with respect to a recording medium, wherein a mass object fixed to a predetermined portion of the positioning member, or a mass object fixed to the positioning member after position adjustment and / or mass selection. Wherein the center of gravity of the positioning member substantially coincides with the center of rotation of the positioning member. 2. A head for reproducing and / or recording on a disk-shaped recording medium, and supporting the head and rotating the head about a predetermined axis to thereby control the head. In a method for manufacturing a rotary head device having a positioning member for positioning with respect to a recording medium, a mass is fixed to a predetermined portion of the positioning member so that a center of gravity of the positioning member and a rotation center of the positioning member are substantially aligned. A method of manufacturing a rotary head device, wherein the rotation type head device is made coincident. 3. A head for performing reproduction and / or recording on a disk-shaped recording medium, and supporting the head and rotating the head about a predetermined axis to form the recording medium. In a method of manufacturing a rotary head device having a positioning member for positioning with respect to a recording medium, a positioning member is adjusted by adjusting a fixed position of a mass added to the positioning member and / or selecting a mass. The center of gravity of the positioning member and the center of rotation of the positioning member are fixed to a predetermined position of the positioning member so that the center of rotation of the positioning member substantially coincides with the center of rotation of the positioning member. A method of manufacturing a rotary head device. 4. The rotary head device according to claim 1, wherein the mass is a curable fluid or gel, and the fluid or gel is cured in a concave portion formed in the positioning member. A rotary head device, wherein the rotary head device is fixed. 5. The rotary head device according to claim 1, wherein the mass is attached to the positioning member in a state where a distance between the mass and a rotation center of the positioning member is adjustable. A rotary head device wherein the position of the mass is fixed so that the center of gravity of the positioning member substantially coincides with the center of rotation of the positioning member. 6. The rotary head device according to claim 1, wherein the mass is a weight capable of selecting a distance from a rotation center of the positioning member in a stepwise manner, and the position of the weight is fixed. The rotation type head device wherein the center of gravity of the positioning member and the center of rotation of the positioning member substantially coincide with each other. 7. The rotary type head device according to claim 4, wherein two concave portions are formed in the positioning member, and two axes respectively connecting the center of these concave portions and the rotation center of the positioning member are orthogonal to each other. A rotary head device. 8. The rotary head device according to claim 5, wherein two masses are provided on the positioning member, and their adjustment directions are orthogonal to each other. 9. The rotary head device according to claim 6, wherein two weights or weight groups are provided on the positioning member, and the weight or the center of gravity of the weight group is connected to the rotation center of the positioning member. A rotary head device, wherein axes are orthogonal to each other.