JPH05258454A - Disk driving device - Google Patents

Abstract

PURPOSE:To eliminate the adverse influence of leak magnetic fluxes on the performance of heads by utilizing an ultrasonic motor by utilizing the pressure contact force for bringing a collet into pressurized contact with a spindle for pressure contact of a friction plate and a piezoelectric driving body. CONSTITUTION:The friction plate 64 is fixed to the outer periphery in the upper part of the spindle 28 and the piezoelectric driving body 65 is fixed by means of a screw 66 to a base 10 in the position facing the friction plate 64. The spindle 28 is brought into pressurized contact with this piezoelectric driving body 75 via the friction plate 64. The force that the center cone collet 27 presses a recording medium 5 to the upper surface of the spindle 28 is utilized for this pressurized contact force. The recording medium is rotationally driven according to the spindle 28 by impressing an electric field to piezoelectric ceramics 67 of such ultrasonic motor. Then, the adverse influence of the leak magnetic fluxes of the magnet for driving the motor on the performance of the heads 30, 31 is eliminated without using a DC motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk drive for rotationally driving a 5.25 "floppy disk or the like.

[0002]

2 to 5 show a conventional 5.25 "floppy disk drive (hereinafter referred to as FDD), FIG. 2 is a top view of the FDD, and FIG. 3 shows the inside of the FDD. FIG. 4 is a sectional view, FIG. 4 is a sectional view of a motor for driving the recording medium, and FIG. 5 is a top view showing the recording medium.

A 5.25 floppy disk (hereinafter referred to as FD) 1 shown in FIG. 5 is a disk-shaped recording medium 5 having a circular opening 4, and the FD 1 is a flexible enderobe 2.
The enderobe 2 accommodated therein has a circular opening 3 for exposing the circular opening in the center, a head sliding contact opening 6, and an index signal hole 7 located concentrically with the circular opening. Are formed.

Next, referring to FIG. 2 to FIG.
The FFD mechanism for recording and reproducing information on and from is configured as follows. Each component is mounted on the base 10. The FD is inserted from an insertion opening (not shown) of the front panel 11 shown in FIG. 2 and has a gap with an upper plate (not shown) fixed on the base 10 via a spacing member (not shown). It is inserted further in the back through. Next, the tip of the FD inserted in the back contacts the ejector 13. When the FD is further pushed in, the ejector 13 rotates in the direction of the arrow A against the spring 14 biased in the direction of the arrow B and is latched to allow the eject lever described later to move. As a result, the FD 1 is housed in the predetermined position.

Next, the clamp mechanism will be described. When the operator presses the eject button 15, the eject lever 16 connected to the eject button 15 moves in the arrow X direction against the spring 17 that urges in the Y direction. When the eject lever 16 is moved by a predetermined distance, the eject lever 16 is latched by the latch 18. Further, when the operator presses the eject button 15, the latch 18 is released, and the eject lever 16 is moved in the Y direction by the spring 17, so that the ejector 1
3 is also rotated in the arrow B direction by the spring 14. By the rotation of the ejector 13, the FD 1 moves in the Y direction and is ejected from the insertion port. When the eject lever 16 moves in the X direction, the rollers 19 and 20 rotatably supported by the eject lever 16 move in the X direction in FIG. 2 (that is, in the B direction in FIG. 3), and the load arm 21 moves in the Y direction in FIG. Move in the direction.

The load arm 21 includes a plate 24 fixed to a plate spring 23 fixed to the upper plate 12 with a screw 22, a plate 25 hinged to the plate 24, and a shaft 26 coupled to the plate 25. A center cone collet 27 is rotatably supported on the shaft 26. A cam portion 24a is provided on the upper surface of the plate 24, and a cam portion 25a is also provided on the plate 25.
Is provided. An approximately concave spindle 28 is rotatably provided facing the center cone collet 27.

In the clamping operation, first, the roller 19 rides on the cam portion 24a of the plate 24 by moving the eject lever 16 in the X direction, moves the plate 24 in the Y direction by a predetermined distance, and the center cone collet 27 moves the FD1. Entering into the opening 4 and into the recess a of the spindle 28, centering the FD 1 and then riding on the cam portion 25a of the plate 25, the center cone collet 27
The exposed part of the FD1 recording medium with the jaw of the spindle 28
By pressing on the upper surface of the FD1 and fixing the FD1 on the spindle.

The magnetic heads 30, 3 are attached to the fixed FD 1.
1 is in sliding contact. The magnetic head 30 is fixed to a carriage 32, and a magnetic head 31 facing the magnetic head 30 is provided.
Is fixed to an arm, which is the carriage 32.
It is rotatably supported above and is biased toward the magnetic head 30 by a spring 33. The carriage 32 is supported by a guide bar 34 so as to be movable in XY directions, and a pin 37 is fixed to the carriage, and the pin 37 is fixed to the base by a stepper motor 35.
It engages with the lead groove of the lead screw 36 directly connected to the. Therefore, the carriage 32 is moved in the XY directions by the rotation of the stepper motor 35.

Next, referring to FIG. 4, the spindle 28
The structure of the motor for rotating the motor will be described. A drive coil 51 is fixed to the lower surface of the base 10 via an insulating material 50, and a PCB (printed circuit board) 52 for supplying electricity to the drive coil is fixed to the lower surface of the coil 51. .. On the other hand, a housing 54 holding a bearing 53 is fixed to the base 10, and the bearing 53 rotatably supports the spindle 28. A rotor 56 is fixed to the end of the spindle 28 with a screw 55, and a drive magnet 57 is fixed to the rotor.

[0010]

In the conventional FDD described above, since the head and the motor are arranged closer to each other, the magnetic flux leaking from the drive magnet of the motor easily affects the head. ing. This adversely affects the recording / reproducing function of the head, and the FD
The performance required for D may not be satisfied. One way to avoid this is to shield the head itself with a high magnetic permeability material such as permalloy, to separate the motor from the head, or to shield the motor itself with a high magnetic permeability material such as permalloy. However, any of these methods is not a practical solution because it causes a problem such as an increase in cost or an increase in the entire FDD.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a disk drive device using an ultrasonic motor, which eliminates the drawbacks of using a motor using a magnet, for example, the influence of leakage magnetic flux on the head.

In order to achieve the above object, the present invention provides
In a disk drive device for performing recording and reproduction by holding a recording medium in pressure contact between a collet and a spindle, an annular wear-resistant member fixed to the spindle and arranged opposite to the wear member. A disk drive device is provided which has a piezoelectric drive member and which presses the abradable member and the piezoelectric drive member by utilizing a press contacting force for press-contacting the collet with the spindle.

[0013]

1 is a block diagram of a preferred embodiment of the present invention.
Will be described. In addition, center corn collet 2
The rotation support structure of No. 7 and the arrangement structure of the heads 30 and 31 are the same as those of the conventional example, and therefore the description thereof will be omitted.

A shaft 60 is provided on the base 10 of the disk drive device.
Are fixed, and the shaft 60 is fixed. The shaft 6
A bearing 61 is fitted to the shaft 0, and the bottom surface of the spindle 28 is fixed to the outer ring of the bearing 61. A tension washer 62 is fixed to the shaft 60.
2 and the bearing 61, a spring 63 is interposed,
Preload the bearing 61. A substantially hollow disk-shaped friction plate 64 made of a material having high wear resistance is fixed to the outer periphery of the upper portion of the spindle 28 with an adhesive or the like. In this embodiment, the spindle 28 and the friction plate 64 are formed by separate members, but the spindle 28 itself may be formed by a wear resistant material.

A hollow cylindrical piezoelectric drive body 65 is fixed to the base 10 by screws 66 on a concentric circle centered on the shaft 60 at a position facing the friction plate 64 of the spindle 28. The piezoelectric driver 65 includes a hollow disk-shaped piezoelectric ceramic 67 and a comb-shaped projection 68 whose upper surface has a circumferentially predetermined pitch.
A hollow cylindrical elastic body 69 having
The piezoelectric ceramic 67 is attached to the bottom surface of the. Further, the spindle 28 is pressed against the piezoelectric driving body 65 via a friction plate 64. This pressure contact force is obtained from the pressing force of the center cone collet 27 pressing the recording medium 5 against the upper surface of the spindle 28, the force of the spring 63 to preload the bearing 61, or both of them.

In such an ultrasonic motor, when an electric field is applied to the piezoelectric ceramic 67, a traveling wave of bending vibration is excited in the peripheral direction of the piezoelectric driving body 68, frictional vibration is applied to the spindle 28, and a predetermined vibration is applied. Driven to rotate. Therefore, the recording medium is also driven to rotate.

The detailed principle of the ultrasonic motor is disclosed in Tokukai Sho 62.
-193571, etc. In the structure of the present invention, since the spindle 28 is pressed against the upper surface of the comb-shaped projection 68 of the piezoelectric driving body 65, the bearing on the surface of the spindle 28 on which the medium is mounted has a certain degree of surface accuracy. It can be configured with one bearing by simply pressing it.

As described above, according to the present invention, the pressure contact force of the ultrasonic motor can be generated without using any special mechanism or parts, and the recording of the head by the magnetic flux leakage of the magnet by using the DC motor. It is possible to eliminate the adverse effect on the reproduction performance and to make the disk drive device smaller and thinner.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a disk drive device according to the present invention.

FIG. 2 is a top view of an FDD.

FIG. 3 is a cross-sectional view showing the inside of an FDD.

FIG. 4 is a cross-sectional view of a motor that drives a conventional recording medium.

FIG. 5 is a top view showing a recording medium.

[Explanation of symbols]

 5 FD 10 Base 28 Spindle 60 Shaft 61 Bearing 64 Friction Plate 65 Piezoelectric Drive Body 68 Cone Tooth Protrusion 69 Hollow Cylindrical Elastic Body

Claims (1)

[Claims] 1. A disk drive device for recording and reproducing by holding a recording medium in pressure contact between a collet and a spindle, and an annular wear resistant member fixed to the spindle, and facing the wear member. A disk drive device, wherein the abradable member and the piezoelectric drive member are pressed against each other by using a pressing force for pressing the collet onto the spindle.