JPS626608Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an actuator for driving a magnetic head in a magnetic disk device, and particularly to the structure of a rotary voice coil motor.

In conventional head actuators, the laminated structure of the arm that supports the magnetic head and the pivot bearing section that supports the pivot shaft are constructed separately, which not only makes the structure of the head actuator complex but also causes resonance. In order to ensure sufficient rigidity in consideration of such factors, the entire actuator has become large, which inevitably increases heat generation and power consumption. In addition, the work of attaching and detaching the arm was extremely troublesome.

In particular, the present invention simplifies the structure of the pivot shaft portion of the laminated arm so that the laminated arm can be easily attached and removed, and also integrates the laminated structure of the arm and the pivot bearing portion to achieve the above-mentioned effect. The aim is to eliminate all such inconveniences.

In order to achieve this object, the present invention provides an actuator for driving a magnetic head in which a plurality of laminated arms supporting a magnetic head are rotationally driven by a coil held in a magnetic field.
comprising a pair of opposing supports forming an actuator main body, and a pivot shaft having bearings at both ends and to which each of the arms is removably fixed;
A pivot shaft is rotatably supported by the opposing support via the bearing, and the outer diameter of one of the bearings is larger and the outer diameter of the other bearing is smaller than the outer diameter of the pivot shaft. It is characterized by

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

A coil 5 wound around a bobbin (not shown) is placed within the magnetic field of a magnet 7 supported by a yoke 9 surrounding it, and by energizing the coil 5, the coil 5 moves left and right along with the bobbin in FIG. Move. An arm 11 is fixed to the bobbin and rotates integrally with the bobbin. The arms 11 have a laminated structure with a number (five stages in the figure) corresponding to the number of magnetic disks (not shown), and each of these arms is fixed to a common pivot shaft 19 with a screw 30 and integrated. The pivot shaft 30 is connected to a pair of plates constituting the actuator main body, that is, the substrate 1.
and the support plate 3, respectively.
It is rotatably supported via 1 and 23. The magnetic head 15 is supported by a head support 13 attached to the tip of each arm 11. One of these read/write heads 15, usually the lowest head, is used as a servo head for reading track position information on the magnetic disk.
Note that 17 is a coil lead wire. As described above, in the present invention, each arm 11 is directly fixed and laminated to the pivot shaft 19 rotatably supported between the substrate 1 and the support plate 3 using the screws 30, etc., so that the laminated structure is extremely simple.

Furthermore, according to the present invention, as shown in _FIG .
The outer diameters d ₁ and d ₃ of No. 3 have the following relationship. That is,
d ₁ > d ₂ > d ₃ . By doing so, when it becomes necessary to remove the arm 11, it can be easily removed. That is, by simply removing the screw 31 fixing the shoulder portion 21A of the bearing 21 to the support plate 3 via the holding plate 41, the pivot shaft 19 can be inserted into the insertion hole 3 of the bearing 21 together with the bearings 21 and 23.
Since it can be easily pulled out from 3, only the laminated arm 11 remains between the substrate 1 and the support plate 3.
The arm can therefore be removed. Of course, in this case, it is necessary to remove the screw 30 that fixes the arm 11 to the pivot shaft 19. Further, it is equal to the inner diameter d ₁ of the insertion hole 33 of the bearing 21 formed in the support plate 3 . The bearing 23 is supported by a holding plate 40 fixed to the back surface of the substrate 1 with screws 35 so as not to slip out from the substrate 1. The bearing 23 is fitted into an insertion hole 37 formed in the substrate 1. Therefore, the inner diameter of the insertion hole 37 is approximately equal to _d3 .

Conversely, when attaching an arm between both plates 1 and 3, the operation is the reverse of the above, that is, the pivot shaft holes of each arm are aligned and stacked, and the pivot shaft 19 and bearing 23 are installed in these holes from above. , then insert the bearing 21 into the pivot shaft 1.
9 and then fix it with the screw 31.

As described above, according to the present invention, the laminated structure of the arm and the structure of the pivot bearing part are simplified, so the structure of the actuator as a whole becomes extremely simple, and the arm can be installed and removed very easily. It is effective.

[Brief explanation of the drawing]

1 is a plan view of a head actuator according to the present invention, FIG. 2 is a left side view of FIG. 1, and FIG. 3 is a sectional view taken along the line -- in FIG. 1...Substrate, 3...Support plate, 5...Coil, 7
...Magnet, 9...Yoke, 11...Arm, 13
... Head support, 15 ... Head, 17 ... Coil leader line, 19 ... Pivot shaft, 21, 23 ...
…bearing.

Claims (1)

[Claims for Utility Model Registration] In an actuator for driving a magnetic head in which a plurality of laminated arms 11 supporting a magnetic head 15 are rotationally driven by a coil 5 held in a magnetic field, a pair of laminated arms 11 forming an actuator main body are provided. A pivot shaft 19 having bearings 21 and 23 at both ends and to which each of the arms 11 is removably fixed is provided. The pivot shaft 19 is rotatably supported through the pivot shafts 21 and 23, and the outer diameter of one of the bearings 21 is larger than the outer diameter of the pivot shaft 19.
An actuator for driving a magnetic head, which has a smaller outer diameter.