JPH0294183A - Magnetic head positioning device - Google Patents

Abstract

PURPOSE:To prevent deformation of the magnetic circuit and central shaft of the title device by printing a cylindrical sleeve coupled with an upper base plate with screws into contact with the upper end face of the central shaft so as to fill up the gap between the upper base plate and central shaft with the sleeve. CONSTITUTION:A coil 6 provided in a magnetic circuit 7 is fixed to one side of a housing 3 opposite to arms 1 and the coil 6 and arms 1 move in one body. The upper part of a central shaft 5 and lower part of the magnetic circuit 7 are respectively supported by an upper and lower base plates 8a and 8b and a sleeve 9 is coupled with the upper plate 8a with a screw 10 and adjustable in height. Namely, the lower end of the sleeve 9 is brought into contact with the upper end face of the central shaft 5 so as to fill up the gap between the shaft 5 and upper plate 8a by adjusting the fitting height of the sleeve 9 coupled with the upper plate 8a with the screw 10 by moving the sleeve in the vertical direction by rotation. When the central shaft 5 is fixed to the upper base plate 8a by tightening the screw 10 after adjusting the fitting height of the sleeve 9, the shaft 5 and magnetic circuit 7 can be fixed to the plate 8a. Therefore, deformation of the shaft 5 and circuit 7 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head positioning device for a magnetic disk drive.

[Conventional technology]

The magnetic head positioning device of a conventional magnetic disk device is
As illustrated in FIG. 3, the central axis 15 is attached to the lower substrate 18b.
After fixing the lower end of the arm 1, the inner ring of the bearing 14 is attached to the center shaft 15, the inner periphery of the housing 13 is attached to the outer ring of the bearing 14, and the plurality of arms 1 each have a magnetic head 12 held at their tip.
are mounted on the housing 13 at a predetermined interval.

On the other hand, the coil 16 is attached to the housing 1 on the opposite side of the arm 11.
3, so that the arm 11 and the coil 16 rotate integrally. A magnetic circuit 17 having a shape that sandwiches this coil 16 is fixed to a lower substrate 181). Upper substrates 1, 8a are provided to support the central shaft 15 and the magnetic circuit 17 above them.

A gap is created between the upper substrate 18a and the central axis 15 or between the upper substrate 1.8a and the magnetic circuit 17. Therefore, a gap is secured either between the upper substrate 18a and the center shaft 15 or between the upper substrate 18a and the magnetic circuit 17, and the shim 21 is inserted into the secured gap. By fixing the shaft 15 and the magnetic circuit 17 with screws 20, the -F section board 18a is fixed.

[Problem to be solved by the invention]

The magnetic head positioning device of the conventional magnetic tisf device, such as a double series, is difficult to assemble due to the insertion of shims, and the dimensional accuracy of the upper board and the assembly accuracy associated with the assembly of the central axis and magnetic circuit are poor. In this case, the upper substrate, the upper substrate, and the center shaft are fixed in a deformed state, which adversely affects thermal off-track and vibration.

[Means to solve the problem]

A magnetic head positioning device for a magnetic disk drive according to the present invention includes a plurality of arms that identify and support magnetic heads at their tips, a housing on which the plurality of arms are loaded at predetermined intervals, and a housing that rotates the housing. A bearing movably supported, a central shaft supporting an inner ring of the bearing, a coil fixed to the housing and moving integrally with the plurality of arms, and a magnetic circuit disposed above and below the coil. a magnetic head positioning device for a magnetic disk drive, comprising: a lower substrate supporting the central axis and a lower part of the magnetic circuit; and an upper substrate supporting the central axis and the upper part of the magnetic circuit; A sleeve is provided, which has a female threaded portion provided at a portion corresponding to the central axis, and is screwed to the female thread so that its height can be adjusted, and the height of the sleeve is changed so that its lower end surface is aligned with the central axis. The upper substrate and the central axis are screwed and fixed by filling the gap between the upper substrate and the central axis by contacting the upper end surface.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
FIG. 3 is a cross-sectional view showing details of section A in the figure.

In FIGS. 1 and 2, the magnetic head 2 is connected to the arm 1.
It is fixed and supported at the tip of. Multiple arms1.
are mounted on the housing 3 in a stacked manner with a predetermined interval maintained. An outer ring of a bearing 4 is fixed to the inner circumference of the housing 3, and an inner ring of the bearing 4 is attached to an inner ring of the central shaft 5. Therefore, the arm 1 can rotate around the central axis 5. A coil 6 installed in a magnetic circuit 7 is fixed on the opposite side of the housing 3 to the arm 1, and the coil 6 and the arm 1 move together. The center shaft 5 and the magnetic circuit 7 are supported by an upper substrate 8a and a lower substrate 8b at their lower and lower portions, respectively. The sleeve 9 is threadably coupled to the upper substrate 8a so that its height can be adjusted. That is, by rotating the sleeve 9 which is threadedly connected to the upper substrate 8a, the sleeve 9 is moved downward, the height is adjusted, and the lower end is brought into contact with the upper end surface of the central shaft 5, and the sleeve 9 is attached to the upper substrate 8a. Fill the gap between the central shafts 5. In this state, by tightening and fixing the upper substrate 8a and the central shaft 5 with the screws 10, the upper sides of the central shaft 5 and the magnetic circuit 7 are fixed to the upper substrate 8a.

By configuring as described above, it is possible to fix the central shaft 5 and the magnetic circuit 7 without deforming them.

〔Effect of the invention〕

As explained above, the magnetic head positioning device of the present invention can fill the gap between the upper substrate and the central shaft by bringing the cylindrical sleeve threadably coupled to the upper substrate into contact with the two end surfaces of the central shaft. By making it possible,
This has the effect of preventing deformation of the magnetic circuit and central axis, and therefore provides a magnetic disk device with small thermal off-track and low vibration level.

It also has the effect of making assembly work easier.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG.
FIG. 3 is a cross-sectional view showing details of part A in the figure, and FIG. 3 is a cross-sectional view showing an example of a conventional magnetic head positioning device. 1.11...Arm, 2.12...Magnetic head, 3
・13・Housing, 4・14・Bearing, 5・15・・
・Central axis, 6・16... Coil, 717・Magnetic circuit,
8a 18a... Upper board, 8b-18b... Lower board, 9... Sleeve, 10.20... Screw, 21.
...Sim.

Claims (1)

[Claims] A plurality of arms that fix and support magnetic heads at their tips, a housing that loads the plurality of arms at predetermined intervals, a bearing that rotatably supports the housing, and an inner ring of the bearing. a central shaft to support, a coil fixed to the housing and moving in unison with the plurality of arms, a magnetic circuit disposed above and below the coil, and a lower part of the central shaft and the magnetic circuit to be supported. In a magnetic head positioning device for a magnetic disk drive, the upper substrate includes a lower substrate that supports the central axis and an upper portion of the magnetic circuit, wherein the upper substrate has a female screw portion provided at a portion corresponding to the central axis. and a sleeve screwed to the female thread so that its height can be adjusted is provided, and by changing the height of the sleeve and bringing its lower end surface into contact with the upper end surface of the central shaft, the sleeve can be connected to the upper substrate. A magnetic head positioning device characterized in that the upper substrate and the central shaft are fixed with screws by filling a gap between the upper substrate and the central shaft.