JPH0538446Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Table of contents] - Overview - Industrial application field - Conventional technology (Fig. 2) - Problems that the invention aims to solve - Means for solving the problems - Actions - Examples (Fig. 1) - Effects of the invention [Summary] This is a stacked actuator arm structure for a magnetic disk device, and is intended to eliminate residual stress and distortion such as torsional stress generated by screw tightening of the arm stack 12. , by placing clamp plates 12c on both outer surfaces of the arm laminate 12, and tightening the arm laminate 12 through the clamp plates 12c to form an integrated structure, each arm 12a, 1
It is possible to prevent the generation of residual stress and distortion in the arms 12b and to prevent relative positional deviation between the arms 12a and 12b due to temperature changes.

[Industrial application field]

The present invention relates to a stacked actuator arm structure for a magnetic disk device. A stacked actuator arm is formed by stacking a plurality of arms each having a magnetic head mounted thereon, and tightening the stacked bodies to integrate them.

In recent years, in magnetic disk devices, due to higher recording densities and expansion of operating temperature environments, the allowable amount of off-track due to temperature changes has become smaller. Therefore, if the residual stress inside the arm due to the tightening force when stacking the arms becomes a kind of release state due to a change in environmental temperature, etc., it will easily be related to off-track, and it is necessary to prevent this.

[Conventional technology]

FIG. 2 is a diagram showing a conventional stacked actuator arm. In the figure, reference numeral 1 indicates a laminated actuator arm, and 3 indicates a bobbin coupled to this arm to constitute a voice coil motor. The actuator arm 1 is arranged to be swingable and rotatable around the rotational center axis α (in the direction of arrows A and B). The actuator arm 1 is formed by stacking a plurality of arms 2a each having a magnetic head 2-1 mounted on its tip to form an arm stack 2, and has tightening bolts 4 (three in this case) passing through it. The arms 2a are integrally formed by pressing and fixing the laminated surfaces of the arms 2a to each other. Reference numeral 5 indicates a stopper pin fixed to the lower surface of the lowermost arm 2a, and reference numeral 6 indicates a fixing portion having a pair of receiving wall surfaces 6a and 6b, which are arranged facing each other at a predetermined interval and for receiving and stopping the stopper pin 5. The swing angle (for example, 20°) of the actuator arm 1 is regulated by the pair of receiving wall surfaces 6a and 6b.

In this way, this conventional example has a structure in which the arm laminate 2 is directly tightened with the tightening bolt 4 and integrated.

[Problem that the invention attempts to solve]

In the above conventional example, the arm 2a of the arm stacked body 2
Since the structure is such that the bolts 4 are directly tightened, residual stress such as torsional stress or distortion occurs in each arm 2a of the arm stack 2 due to the tightening of the bolts 4. Therefore, when the stress becomes a kind of release state (when the tightening force of the arm laminate 2 changes) due to temperature changes and differences in linear expansion coefficients between the arms 2a and the bolts 4, each arm 2a becomes irregular. deformed,
There is a problem in that a relative positional deviation occurs between the arms 2a, and as a result, a relative positional deviation occurs between the data head (data arm) with respect to the servo head (servo arm), and off-track is likely to occur.

The present invention was created in view of these problems, and it is a magnetic disk that can prevent relative positional deviation between the servo head (servo arm) and data head (data arm) even if the environmental temperature changes. The object is to provide a stacked actuator arm structure for the device.

[Means for solving problems]

As a means to solve the above-mentioned problems, in the present invention, in a stacked actuator arm structure of a magnetic disk device in which magnetic heads are mounted and are arranged so as to be swingable and rotatable, each magnetic head 12-1 is A plurality of mounted arms 12a and 12b are stacked to form an arm stack 12, and the arm stack 12 is sandwiched from both sides on the outer surface of each arm stacked on the outermost side of the arm stack 12. Clamp plates 12c are arranged respectively, and the arm laminate 12 is tightened via the clamp plates 12c by tightening members 14 such as tightening bolts arranged at a plurality of places to form an integrated structure. A stacked actuator arm structure for a magnetic disk device is provided.

[Effect]

Since the arm laminate 12 is clamped via the clamp plate 12c, the clamp plate 14 absorbs residual stress and distortion such as torsional stress when the clamp member 14 is tightened, and each arm 12, 12b is The internal stress (in the direction perpendicular to the surface) can be applied almost evenly, and the generation of residual stress and distortion can be prevented. Therefore, even if the tightening force on the arm laminate 12 changes due to environmental temperature changes, differences in linear expansion coefficients between the arm laminate 12 and the tightening member 14, etc. (even if it becomes a kind of stress release state) , irregular deformation of each arm 12a, 12b can be prevented, and generation of relative positional deviation between each arm 12a, 12b can be prevented.

〔Example〕

1A and 1B are views showing an embodiment of the present invention, in which a is a plan view and b is a side view taken in the direction of arrow C of a.
In the figure, reference numeral 11 denotes a laminated actuator arm, and 13 denotes a fixing screw 13a to this arm 11.
1 and 2 show bobbins coupled together to form a voice coil motor (not shown). The actuator arm 11 is arranged so as to be swingable and rotatable around the rotation center axis α (in the direction of arrows A and B) via a rotation shaft 15 and bearings 16A and 16B that support the shaft. The actuator arm 11 is
A plurality of data arms 12a (six in this case) each having a magnetic head 12-1 mounted on its tip.
and one servo arm 12b are stacked as shown in the figure to form an arm stack 12, and each arm 12a on the outermost side of this stack 12 [each arm 12a at the top and bottom ends in Figure B] is The clamp plates 12c are arranged, and both of these clamp plates 12c
The arms 12a and 12b are tightened with tightening bolts (three bolts in this case) 14 through each clamp plate 12c while holding the arm stack 12 between the arms 12a and 12b.
It is integrally formed by pressing and fixing the laminated surfaces of the two together. The clamp plate 12c is connected to the arm 12a,
It is made of the same material as 12b.
Reference numeral 17 denotes a through space provided parallel to the axis α at the joint between the actuator arm 11 and the bobbin 13, and 18 a stopper shaft fixedly provided on the end surface of the bobbin 13 located within the space 17. A receiving member 19 having between receiving walls 18a and 18b
1A and 1B respectively show a stopper shaft which is arranged parallel to the axis α between the receiving wall surfaces 18a and 18b and whose both ends are fixed to the apparatus frame 20 side. The receiving wall surfaces 18a, 18b and the stopper shaft 19 restrict the swing angle (for example, 20 degrees) of the actuator arm 11.

In this example, as described above, the clamp plate 12 is placed on each outermost arm 12a of the arm stack 12.
The structure is such that the arm laminate 12 is indirectly tightened with a tightening bolt 14 via the bolt 14. With this configuration, residual stress such as torsional stress and distortion generated when tightening the bolt 4 can be absorbed by the clamp plate 12c, and each arm 12
A uniform pressing force can be applied only in the stacking direction to a and 12b.

[Effect of idea]

As explained above, according to the present invention, the arm laminate 12 is integrated by being tightened with the tightening bolt 14 via the clamp plate 12c, so that residual torsional stress etc. when tightening the bolt 14 is eliminated. The stress and strain are absorbed by the clamp plate 12c,
Since a uniform pressing force (internal stress) can be applied to each arm 12a, 12b only in the stacking direction (direction perpendicular to the stacking surface), environmental temperature changes and the line between the arms 12a, 12b and the tightening bolt 14 can be applied to each arm 12a, 12b. Even if the internal stress is slightly released due to a difference in expansion factor, etc. (even if the tightening force of the arm stack 12 changes), relative positional deviation between the arms 12a and 12b is prevented from occurring. In other words, it is possible to prevent relative positional deviation of each data head (data arm 12a) with respect to the servo head (servo arm 12b), and as a result, the occurrence of off-track can be prevented.

[Brief explanation of the drawing]

Figures 1a and b are diagrams showing an embodiment of the present invention;
The figure shows a conventional example. In FIG. 1, 11 is a laminated actuator arm, 12 is an arm laminate, 12-1 is a magnetic head, 12a is a data arm, 12b is a servo arm, 12c is a clamp plate, 13 is a bobbin, 13
a is a fixing screw, 14 is a tightening bolt (tightening member),
15 is a rotating shaft, 16A, 16B are bearings, 1
7 is a through space, 18 is a receiving member, 18a, 1
8b is a stopper shaft receiving wall surface, 19 is a stopper shaft, 20 is a device frame, and α is a rotation center axis.

Claims (1)

[Claims for Utility Model Registration] In a stacked actuator arm structure of a magnetic disk device in which a magnetic head is mounted and is arranged to be swingable and rotatable, a plurality of arms 12a each having a magnetic head 12-1 mounted therein. , 12b are laminated to form an arm laminate 12, and clamp plates 12c are arranged on the outer surface of each arm laminated on the outermost side of the arm laminate 12 so as to clamp the arm laminate 12 from both sides. , a stacked actuator for a magnetic disk device, characterized in that the arm stack 12 is integrally formed by tightening the arm stack 12 via the clamp plate 12c with tightening members 14 such as tightening bolts arranged at a plurality of locations. Yueta arm structure.