JPS59210569A - Oscillation type head positioning mechanism - Google Patents

Abstract

PURPOSE:To change the head arm easily without lowering the rigidity of a bearing by forming an end of a rotation shaft and inside of the inner ring of the bearing to tapered form. CONSTITUTION:A rotation shaft 11 an end of which is formed to tapered shape is interposed between the inner ring of a bearing 4b and a rotation shaft 10, and is a ring having tapered at the inside. The ring 11 and inner ring of the bearing 4b, a housing 5 and the outer ring of the bearing 4b, and the rotation shaft 10 and inner ring of the bearing 4a are fixed tightly by bonding. Pressure is given to the outer ring of the bearing 4a by elastic pressing of springs 9 and 12 in the direction of thrust and radial directions. Bearings 4a, 4b, the rotation shaft 10 and housing 5 are assembled rigidly without play, and bearings of large outer diameter can be used. Accordingly, the arm 2 can be changed simply without lowering resonance frequency of the positioning mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a swing type head positioning mechanism that can be easily assembled and disassembled.

Conventionally, a swing type head positioning mechanism for accurately positioning a magnetic head on a recording track of a magnetic disk, etc.
There was one shown in Figures 1 and 2. FIG. 1 is a front view showing a conventional swing type head positioning mechanism, and FIG. 2 is a sectional view taken along the line A--A of the swing type head positioning mechanism shown in FIG. In each of the above figures, 1 is a magnetic head, 2 is a head arm having the magnetic head 1, and 3 is a head arm 2.
is the rotating shaft to which is screwed, 4a and 4b are the rotating shafts 3
A pair of rings, 5 is a housing, 6 is a linear motor coil, 7 is a permanent magnet, 8 is a magnetic disk, and 9 is a spring. In the above mechanism, the coil 6 of the linear motor is in the magnetic field created by the permanent magnet 7, and when a current is passed through the coil 6, a driving force is generated in the direction of arrow i or i' shown in FIG. The magnetic head 1 is moved in the direction of arrow J or j' shown in FIG. 1 to position the magnetic disk 8 at a target track. Also, the rotating shaft 3 and each bearing 4a.

In order to eliminate play between the pairings 4a and 4b, the inner rings of each of the pairings 4a and 4b are completely bonded to the rotating shaft 3. Furthermore, the outer ring of the bearing 4b and the housing 5 are also bonded together, and only the outer ring of the bearing 4a and the housing 5 are bonded, leaving a slight gap between them. Preload due to elastic compression can be seen. Further, the head arm 2 is fixed to the rotating shaft 3 using a restraining screw.

However, in the conventional mechanism described above, once assembled, it is very difficult to remove the head arm 2, and if the magnetic head 1 is damaged, the entire mechanism has to be replaced. In order to improve this, the system shown in FIG. 3 has been proposed. FIG. 3 is a sectional view showing another modification of the swing type head positioning mechanism shown in FIG. 2. Monoke shown in Figure 3,
The inner ring of each bearing 4a, 4b and the rotating shaft 3
However, the outer ring of each bearing 4a, 4b and the housing 5 are not bonded, and the outer diameter of one of the bearings 4b is made smaller than the diameter of the rotating shaft 3. Ru. Thereby, even after assembly, the rotary shaft 3 can be easily pulled out from the nozzle 5, and the head arm 2 can be easily replaced. However, in this case, since the outer diameter of the bearing 4b is small, its rigidity is reduced, and when the number of head arms 2 is increased, the mechanical resonance frequency of the oscillating head positioning mechanism becomes low. Therefore, there was a drawback that the positioning accuracy of the oscillating head deteriorated. This invention was made to eliminate the drawbacks of the conventional device as described above. A swing type head positioning mechanism in which a head arm having a magnetic head is attached and the head arm swings around the rotation axis by the driving force of a full linear motor,
One end of the rotating ah and the inward side of the inner ring of the bearing are each formed into a tapered shape, and the swinging type allows the head arm to be easily replaced without reducing the rigidity of the bearing. The purpose is to provide a head positioning mechanism.

An embodiment of the present invention will be described below with reference to the drawings. Fourth
The figure is a sectional view showing a swing type head positioning mechanism which is an embodiment of the present invention, and the same parts as in Figs. 2 and 3 are designated by the same reference numerals, and detailed explanation thereof will be omitted. . In the figure, 10 is a rotating shelf with one end formed into a tapered shape, and 11 is a ring interposed between the inner ring of the bearing 4b and the rotating shaft 1o, the inner surface 11 of which is tapered. The ring 11 and the inner ring of the bearing 4b, the housing 5, the outer ring 5 rotating shaft 1o of the bearing 4b, and the inner ring of the bearing 4a are all securely fixed by adhesive. Furthermore, the outer ring of the bearing 4a is preloaded by elastic compression in the thrust direction and the radial direction by a spring 9 and a spring 12, respectively.

The swing type head positioning mechanism of the present invention has the above-described structure, so that each of the bearings 4a, 4b and the rotation 11
110 and the housing 5 are securely attached and assembled without play, and (each bearing 4a
, 4b can also be used with a large outer diameter, so the swing type head positioning mechanism allows the head arm 2 to be easily replaced without lowering the resonance frequency of the swing type head positioning mechanism. configured.

In the above embodiment, the ring 1 is interposed between the inner ring of the bearing 4b and the rotating shaft 10 and has a tapered inner surface.
1 is used, but as shown in another embodiment of the invention shown in FIG. 5, instead of using the ring 11, the inner surface of the inner ring of the bearing 13 is formed into a tapered shape. This embodiment has the same effect as the above embodiment.

As described above, according to the swing type head positioning mechanism according to the present invention, one end of the rotating shaft and the inner surface of the inner ring of the bearing are each formed into a tapered shape, so that the rigidity of the bearing is reduced. This has the excellent effect of making it possible to replace the head arm extremely easily and without any trouble, and further improving the positioning accuracy of the swinging head.

[Brief explanation of drawings]

Fig. 1 is a front view showing a conventional swing type head positioning mechanism, and Fig. 2 is an A-A of the swing type head positioning mechanism shown in Fig. 1.
3 is a cross-sectional view showing another modification of the swing type head positioning mechanism shown in FIG. 2; FIG. FIG. 5 is a sectional view showing a swing type head positioning mechanism according to another embodiment of the present invention. In the figure, 1...Magnetic head, 2...Head arm, 3, 10--Rotating shaft, 4"+4b113-...Bearing, 5...Housing, 6...Coil, 7...
...Permanent magnet, 8...Magnetic disk, 9,12...
Spring, 11... ring. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Agent: Masuo Oiwa June 1980 Don 2: Mr. Commissioner of the Japan Patent Office 1, Indication of the case: Japanese Patent Application No. 58-66112 2, Title of the invention: Oscillating head positioning mechanism 3: Address of the person making the amendment: 2 Marunouchi, Chiyoda-ku, Tokyo 2-35 Chome,
Subject of amendment: 1. Detailed explanation of the invention in the specification and drawings. Day 6. 4th page, lines 8 to 9, ``oscillating head'' is corrected to ``head''. c2) & Correct the accompanying drawings Figures 4 and 5 as shown in the attached sheet. Figure 4 Figure 5

Claims (2)

[Claims] (1) A swing type head positioning mechanism in which a head arm having a magnetic head is attached to a rotating shaft supported by bearings at both ends, and the head arm is swung around the rotating shaft by the driving force of a linear motor, A swing type head positioning mechanism, wherein one end of the rotating shaft and an inner surface of the inner ring of the bearing are each formed into a tapered shape. (2) The tapered shape formed on the inner surface of the inner ring of the bearing is formed by a ring that is interposed between the inner ring of the bearing and the rotating shaft and whose inner surface is tapered. The oscillating head positioning mechanism according to scope 1.