JPS6341658Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The present invention relates to a magnetic disk device that records and reproduces information on a disk-shaped recording medium using a magnetic head, and in particular, a magnetic disk device in which the magnetic head is fixed and a predetermined track of the recording medium is tracked. It relates to an actuator mechanism that is rotated to be selected.

(b) Prior Art and Problems A magnetic disk device rotates a disk-shaped medium by a spindle mechanism, and the magnetic head is moved to a predetermined position of the medium by rotation of an actuator mechanism having a swing arm provided with a magnetic head. It is configured to select a track and perform recording/playback.

Such a magnetic disk device is formed as shown in FIG. FIG. 1 is a side view schematically showing a magnetic disk device.

A plurality of media 4 stacked at predetermined intervals by spacers 5 are mounted on a spindle mechanism 11 fixed to the frame 1, and rotated as shown by arrow A. This spindle mechanism 11 includes a stator 2 fixed to a frame 1, and a shaft 8 rotatably held by the stator 2 via a bearing 3.
The rotor 7 includes a hub 6 fixed to the hub 6, and a rotor 7 fixed to the inner circumferential surface of the hub 6.
The rotor 7 is formed by a magnet,
By energizing the electromagnetic coil 2A provided on the stator 2, the rotor 7 is driven to rotate about the shaft 8 in the direction of arrow A. On the other hand, similarly frame 1
A swing arm 9A and a voice coil motor 9B are provided on the actuator mechanism 9 fixed to the actuator mechanism 9. A magnetic head is fixed to the tip of the swing arm 9A, and the swing arm 9A is rotated by the voice coil motor 9B. As a result, a predetermined track is selected by the magnetic head and recorded and reproduced.

Such an actuator mechanism is constructed as shown in FIG. In FIG. 2, a is a plan view and b is a side view of a conventional actuator mechanism.

The swing arm 9A-1 has a through hole 9A-4 inserted into the rotation shaft 9D, seats 9A-1 and 9A-2 that provide a predetermined distance from each other when multiple pieces are stacked, and a punch hole for reducing mass. 9A-3, 9A-
4, 9A-5 are provided, and furthermore, a magnetic head 9G and a servo head 9H are fixed to the tip via a gimbal 9F. A plurality of swing arms 9A are fixed to each other by screwing screws 9C to locations where seats 9A-1 and 9A-2 of the swing arms 9A are provided, thereby forming an arm assembly 9-1. This arm assembly 9-1 is inserted into the rotation shaft 9D and has a screw hole 9D-2 provided in the rotation shaft 9D.
It is fixed by screwing the screw 9E into the. A flat portion 9D-1 is provided on the surface of the rotating shaft 9D to which the arm assembly 9-1 is fixed, and consideration is given so that the through hole 9A-6 is evenly abutted.

Voice coil motor 9B is arm assembly 9-1
Voice coil 9B-1 and frame 1 fixed to
When the voice coil 9B-1 is energized, the arm rotates around the rotating shaft 9D, which is rotatably held by the frame 1A via the bearing 9I. Rotate the assembly 9-1. Therefore, the magnetic head 9E and servo head 9H are moved along the recording surface of the medium 4 in the direction of arrow B, and a predetermined track is selected for recording and reproduction.

When forming such an arm assembly 9-1, the swing arms 9A are stacked so that the through holes 9A-6 of the swing arms 9A are concentric. However, it is impossible to make the surfaces of the respective through holes 9A-6 the same, and a step occurs in the thickness of the swing arm 9A in the stacking direction. Such a step causes distortion in the arm assembly 9-1 when the screw 9E is tightened.

Electronic devices generally have an allowable operating temperature of 0° to 40°C, and when operated in this temperature range, the aforementioned strain due to expansion and contraction of the swing arm 9A has the drawback of deforming the arm assembly 9-1. was. When the arm assembly 9-1 is deformed in this way, the magnetic head 9G and the servo head 9H fixed to their respective tips are misaligned, which causes an off-track problem when recording and reproducing the medium 4.

(c) Purpose of the invention The purpose of the present invention is to improve the rotation shaft that is inserted into the through hole of the swing arm and fixed thereon, and to provide one that eliminates the above-mentioned problems.

(d) Structure of the invention The purpose of the invention is to provide such an actuator mechanism in which the shaft diameter of the rotating shaft is formed by a large diameter part that fits into the through hole and a small diameter part that has a gap. , and the actuator mechanism is characterized in that the large diameter portion and the small diameter portion are provided at a predetermined pitch.

(e) Example of the invention The present invention will be explained in detail below with reference to FIG.
FIG. 3 shows an embodiment of the actuator mechanism according to the present invention, in which a is a side view and b is a detailed view.

The rotation shaft 9K is provided with a large diameter portion D2 and a small diameter portion D1, and the large diameter portion D2 is fitted into a through hole 9A-6 of a predetermined swing arm 9A to which it is fixed. All have the same configuration as in FIG.

The large diameter portion D2 of the rotating shaft 9K, which is rotatably held by the frame 1A via the bearing 9I, is a flat portion 9 with a smooth outer periphery, as shown in detailed diagram b.
A screw hole 9K-2 is provided at the center of K-1 and its flat portion, and is located at a fixed portion to which the arm assembly 9-1 is fixed. Therefore, when the screw 9E is tightened, the arm assembly 9-1 comes into contact with the large diameter portion D2, and the small diameter portion D1 obtains a gap with the through hole 9A-6 provided in the swing arm 9A. I can do it. When the rotation axis 9K is formed in this way, the contact point with the arm assembly 9-1 is made so that the width T of the large diameter portion D2 is smaller than the thickness of the swing arm 9A, which is the same as in the conventional stacked swing arm 9A. Screw 9 no longer touches the entire surface.
E is brought into contact only with the swing arm 9A to which it is screwed. Therefore, the aforementioned distortion of the arm assembly 9-1 is reduced, and no deformation of the arm assembly 9-1 occurs within the allowable operating temperature range.

(f) Effects of the Invention As explained above, in the present invention, the rotating shaft 9K is formed by providing a large diameter portion D2 and a small diameter portion D1 at a predetermined pitch. As a result, distortion of the arm assembly 9-1 fixed to the rotating shaft 9K can be reduced, deformation of the arm assembly 9-1 due to temperature changes is eliminated, and troubles such as off-track during recording and reproduction can be prevented, resulting in practical effects. is large.

[Brief explanation of the drawing]

Fig. 1 is a side view schematically showing a magnetic disk device, Fig. 2 is a plan view of a conventional actuator mechanism, b is a side view, and Fig. 3 is an embodiment of the actuator mechanism according to the present invention. Side view, b, shows a detailed view of the pivot axis. In the figure, 1 and 1A are frame, 2 is stator, 3 is bearing, 4 is medium, 5 is spacer, 6 is hub, 7 is rotor, 8 is shaft, 9 is actuator mechanism, 9A is swing arm, 9B is 9C and 9E are screws, 9F is a gimbal, 9G is a magnetic head, 9H is a servo head, 9I is a bearing, 9D is a rotating shaft, 9-1 is an arm assembly, and 11 is a spindle mechanism.

Claims (1)

[Scope of utility model registration request] A magnetic head that performs recording and reproduction, a rotating shaft that is rotated, and a swing arm that has a through hole that is inserted into the rotating shaft and to which the magnetic head is fixed, and a plurality of the swing arms are laminated and clamped so that the respective through holes are concentric to form an arm assembly, the rotation shaft is inserted into the through hole, and the arm assembly and the rotation shaft are fixed at a predetermined location. In an actuator mechanism that moves the magnetic head through the arm assembly, the rotation of the rotation shaft is such that the shaft diameter of the rotation shaft is equal to the gap between the large diameter portion fitted into the through hole. 1. An actuator mechanism characterized in that the actuator mechanism is formed by a small diameter part having a diameter, and the large diameter part and the small diameter part are provided at a predetermined pitch.