JPH09306111A - Swivel actuator manufacturing method - Google Patents

Abstract

The present invention relates to a method of manufacturing a rotary actuator that rotates a magnetic head so as to move the magnetic head with respect to a magnetic disk in order to select a recording track of the magnetic disk. Provided is a method for obtaining a highly accurate and highly rigid actuator that is less affected by thermal expansion even if there is a large change in environmental temperature or a temperature rise due to self-heating. SOLUTION: A plurality of steps 2a, 2 are provided on the outer circumference of a holder 2 made of a metal material having a through hole 3 into which a central axis of rotation is inserted.
b and 2c are formed, and the through holes formed at the other ends of the plurality of arms 1 made of metal to which the magnetic heads are attached are formed at the other ends.
Each of them is press-fitted into the stepped portions 2a, 2b, 2c of the holder 2, and after that, the other end of the arm 1 together with the drive coil 4 is molded and integrated with the holder 2 by the resin material 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a swing type actuator for rotating a magnetic head so as to move a magnetic head to select a recording track on a magnetic disk in a magnetic disk device (International Patent Classification G11B 3/31). )
It is about.

[0002]

2. Description of the Related Art A conventional method for manufacturing a swing type actuator is to install a plurality of arms in a molding die as shown in US Pat. No. 5,382,851.
A manufacturing method is known in which the cores are aligned and fixed with a resin. Hereinafter, a method of manufacturing the conventional rotary actuator will be described.

FIG. 5 is a plan view of a conventional swivel actuator, FIG. 6 is a side sectional view of the swivel actuator, and FIG. 7 is a plan view of an arm used in the swivel actuator.

In the manufacturing method, as shown in FIG. 7, an arc-shaped notch 1a is formed at the other end of an arm 1 made of a metal material having a magnetic head (not shown) mounted at one end. Three arms 1 are arranged in the mold at a predetermined distance, and a drive coil 4 is also arranged in the mold in a predetermined positional relationship with the arm 1. After that, the respective arms 1 and the drive coil 4 are integrally connected by molding with a resin material.

At that time, a holder portion 2 having a through hole 3 is formed of a resin material, and the rotation center shaft is attached to the through hole 3 via a bearing. In addition,
Reference numeral 5 is a grounding pin inserted in a predetermined through hole in each arm 1 and is inserted before resin molding.

[0006]

However, in the above-described conventional manufacturing method, there is a problem that the production efficiency is poor because it is necessary to fit the arms into the molding die one by one, and the molding is performed. Since the coefficient of thermal expansion of the resin member for fixing the arm differs from that of the arm, there is a problem in that the arms are misaligned due to a large change in the environmental temperature or self-heating.

[0007]

In order to solve the above problems, the actuator manufacturing method of the present invention forms a plurality of steps on the outer periphery of a holder made of a metal material having a through hole into which a rotation center axis is inserted. , The other end of each of the plurality of arms made of metal on one end of which the magnetic head is mounted is press-fitted into the stepped portion of the holder, and thereafter, the other end of the arm together with the drive coil is attached to the holder by a resin material It is characterized by being molded and integrated, and it is possible to increase rigidity by press-fitting and fixing the metal arm to the metal holder, mechanically connecting it, and reinforcing it with resin. By pressing the metal arm into the metal holder, it is possible to take the ground at the same time, and more than one arm can be attached at the same time, improving production efficiency. It can be.

Further, even if there is a large change in environmental temperature or a temperature rise due to self-heating of the equipment, since the arm and the holder are both made of metal, the misalignment of the arm due to thermal expansion is minimized. It is possible to provide an actuator capable of performing the above.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) With reference to FIG. 1 and FIG. 2, an example of using three arms will be described below as an embodiment of the present invention according to claim 1 and claim 2 of the present invention. explain. FIG. 1 is a plan view of an embodiment of an actuator manufactured by the method for manufacturing a swing actuator of the present invention, and FIG. 2 is a side sectional view of the embodiment.

Reference numeral 2 denotes a holder made of metal, which has a through hole 3 for mounting a rotation center shaft in the center thereof, and a plurality of cylindrical steps having different diameters with the through hole 3 as a center on the outer periphery thereof. Portions 2a, 2b, 2c are formed. On the other hand, at the other end of the arm 1 made of a metal material, the cylindrical step 2 is provided.
Through holes that are respectively fitted into a, 2b, and 2c are formed, and the through holes of the arms 1 are the stepped portions 2a, 2b, and
2c is press-fitted in the direction of the central axis of rotation, and in that state is arranged at a predetermined position of the molding die together with the drive coil 4,
It is integrally molded with the resin material 6.

In the present invention, since the arm 1 is press-fitted and fixed to the metal holder 2, the arm 1 and the holder 2 are different from the conventional structure of the actuator according to the present invention. Since it is firmly fixed, it has higher rigidity than fixing by resin alone and can minimize misalignment.
Furthermore, even if there is a large change in environmental temperature or a temperature rise due to self-heating of equipment, both the arm and the holder are made of metal, so the misalignment of the arm due to the difference in thermal expansion should be minimized. It is also possible to press-fit the metal arm into the metal holder and simultaneously ground it.

(Embodiment 2) Next, claim 3 of the present invention
Embodiments of the invention described in 1. will be described with reference to FIGS. 3 and 4. FIG. 3 is a plan view of an embodiment of an actuator produced by the method for manufacturing a swing actuator of the present invention, and FIG. 4 is a side sectional view of the embodiment. The same reference numerals are used for the same components as those in the first embodiment described above.

In FIG. 3, a plurality of annular cut grooves 2 d having a constant diameter centered on the through hole 3 are formed at a predetermined interval on the outer peripheral surface of the metal holder 2, and the other end of the arm 1 is formed. A U-shaped notch that fits in the annular cut groove 2d is formed in each of these. That is, the width of the U-shaped notch formed in the other end of the arm 1 is slightly smaller than the diameter of the cut groove 2d and slightly thicker than the width of the cut groove 2d. The U-shaped cutout portion is press-fitted into the annular cut groove 2d from a direction perpendicular to the rotation center axis and fixed, and in that state, the drive coil 4 is placed at a predetermined position of the molding die.
The resin material 6 is integrally molded. The actuator of this embodiment can also obtain the same effects as those of the above-described second embodiment.

[0014]

As described above, according to the method for manufacturing a swing type actuator of the present invention, since the arm and the holder are firmly fixed to press and fix the arm in the metal holder, the resin The rigidity is higher than that of fixing only by itself, and the misalignment can be minimized. Furthermore, even if there is a large change in environmental temperature or a temperature rise due to self-heating of equipment, both the arm and the holder are made of metal, so the misalignment of the arm due to the difference in thermal expansion should be minimized. Is possible and also
The metal arm can be pressed into the metal holder to simultaneously ground.

[Brief description of drawings]

FIG. 1 is a plan view of a swivel actuator manufactured by a swivel actuator manufacturing method according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the swing actuator.

FIG. 3 is a plan view of a swivel actuator manufactured by a swivel actuator manufacturing method according to another embodiment of the present invention.

FIG. 4 is a side sectional view of the swing actuator.

FIG. 5 is a plan view of a conventional rotary actuator.

FIG. 6 is a side sectional view of the conventional rotary actuator.

FIG. 7 is a plan view of an arm used in the conventional rotary actuator.

[Explanation of symbols]

 1 Arm 2 Holder 2a, 2b, 2c Step 2d Cut groove 3 Through hole 4 Drive coil 5 Ground pin 6 Resin

Claims (3)

[Claims] 1. A plurality of steps are formed on the outer periphery of a holder made of a metal material having a through hole into which a central axis of rotation is inserted, and one end of each of a plurality of arms made of metal on which a magnetic head is mounted is formed. A swivel actuator manufacturing method, comprising press-fitting each into a stepped portion of the holder, and after that, molding the other end of the arm together with a drive coil into the holder with a resin material to integrate them. 2. A plurality of steps formed on the outer periphery of the holder are cylindrical steps having different outer diameters about the rotation center axis, and the other ends of the plurality of arms respectively have the cylindrical shape. 2. The swivel actuator according to claim 1, wherein through holes are formed so as to fit into the steps of the holder, and the through holes are press-fitted into the cylindrical steps from the direction of the rotation center axis of the holder. Production method. 3. A plurality of steps formed on the outer periphery of the holder are annular grooves formed concentrically around the rotation center axis, and the other ends of the plurality of arms are respectively provided with the annular grooves. A U-shaped notch that fits is formed,
The swivel actuator manufacturing method according to claim 1, wherein the notches are respectively press-fitted into the annular groove from a direction perpendicular to the rotation center axis.