JPS60209979A - Magnetic head driver - Google Patents

Abstract

PURPOSE:To improve the positioning accuracy of a magnetic head and to decrease the number of parts together with reduction of the drive power of a stepping motor, by recording and reproducing the tracks ranging from the most inside circumference through the most outside circumference of a magnetic disk at a revolving angle of >=360 deg. of a drive motor and with a driver that converted the revolution of the drive motor into a linear motion of an arm. CONSTITUTION:In a conventional case, a capstan is put into a step motor shaft and a steel band is fixed to the capstan in an a-turn for drive of the capstan. In this example, however, a steel band 20 is wound directly round a step motor shaft 9 in a-turn and then fixed into an attachment hole 21 with a screw 22. The band 20 has a form including the convex and concave shapes combined alternately. The attachment holes 23 at both ends of the band 20 are fixed to a lower arm as conventional. Thus a revolving angle of 360 deg. is obtained with no interference of the band 20 by securing a convex/concave form at an area where the band 20 is fixed to the shaft 9.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head drive device used for recording and reproducing a flexible double-sided magnetic disk.

Conventional Structure and Problems The general structure of a conventional magnetic head drive device will be explained with reference to FIG. Recording and reproduction is performed by sandwiching the magnetic disk 1 between an upper magnetic head 2 from the upper surface of a flexible magnetic disk 1 that rotates at a predetermined rate and a lower magnetic head 3 from the lower surface. The other end of the upper arm 4 is engaged with the lower arm 6 by a hinge 6 with a pressing spring, and is integrally constructed with the lower arm 6 so as to be able to move toward the center of the magnetic disk 1 while holding the magnetic disk 1 therein. There is.

The magnetic heads 2 and 3 move toward the center of the magnetic disk 1 at predetermined distances by sliding the lower arm 6 that is engaged with two parallel guide bars 7 facing toward the center of the magnetic disk. Therefore, recording and reproduction are performed on magnetic disks on rotating concentric circles.

On the other hand, a stepping motor 80 for driving a magnetic head and a rotating shaft 9
The other end of the steel band 11 is passed through the slot part 12 of the steel band 11 as shown in the expanded view in FIG. The capstan 1o and the steel band 11 are integrated. Mounting holes 16 at both ends of the steel band 11.
16 is fixed to the lower arm 5 with a mounting screw 17 as shown in FIG. 1 while applying tension to the steel band 11.

The magnetic head drive device as described above converts the rotational motion of the stepping motor 8 into linear motion using the steel band 11, and the magnetic heads 3 and 2 attached to the lower arm 5 and the upper arm 4 via the guide bar 7 drive the magnetic disk 1. It is designed to slide on both sides. It is well known that the magnetic head of a so-called floppy disk device is driven by the above configuration, and a still band is generally used as an inexpensive means of driving with little backlash.

However, since the steel band 11 is provided with a mounting screw 14, as shown in FIG. Must be used within 00.

For this reason, the accuracy of indexing the step angle of the stepping motor or the dimensional accuracy of the parts of the capstan 10 must be high. On the other hand, floppy disk drives are required to have higher precision in the positioning dimensions of magnetic heads due to higher density recording.

Purpose of the Invention The present invention takes into account the advantages of the conventional steel band described above, and provides an inexpensive magnetic head drive device with good productivity that improves the positioning accuracy of the magnetic head, reduces the number of parts, and reduces the driving force of the stepping motor. It provides:

Structure of the Invention The present invention is a drive device in which both ends of a steel belt wound α around a rotatable drive motor shaft are fixed to an arm provided with a magnetic head, and the rotation of the drive motor is converted into linear motion of the arm. Therefore, the drive motor is configured to record and reproduce tracks from the innermost circumference to the outermost circumference of the magnetic disk with a rotation angle of 360 degrees or more, and since the step motor rotation of 36o0 is obtained, the step angle accuracy of the step motor is At the same time, the driving force of the step motor is halved, and capstan parts are not required, making it possible to position the magnetic head with good productivity and product characteristics.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 4 and 6. FIG. 4 is an explanatory diagram of the operation of the present invention, and FIG. 6 is a developed view of a steel band used in one embodiment of the present invention. Conventionally, a capstan was inserted into the step motor shaft, and a steel band was fixed to the capstan in an α winding to drive the motor, but in this embodiment, the steel band 2o is directly wound around the step motor shaft 9 in an α winding. It was fixed in the mounting hole 21 with a set screw 22. It takes the form of a steel band. First, Figure 4A shows the end state when the band is moved to the left by rotating clockwise as shown by the arrow.
Further, FIG. 4 shows the final state when the step motor shaft is rotated to the left and the steel band 20 is moved to the right.

That is, approximately 3,600 rotation angles are obtained for one rotation by the two openings (A) in FIG. In addition, when attaching both ends of the steel band, the holes 23 are fixed to the lower arm as in the conventional case.

It is possible to obtain a rotation angle of 360° without any interference.

In the embodiment, the diameter of the step motor shaft is 180 degrees with respect to the diameter of the conventional capstan, and in the case of the capstan, the moving distance of the predetermined magnetic head was a rotation angle of 180 degrees, so in the present invention, the rotation angle was 36 degrees. Equivalent head movement distances were obtained.

As described above, according to the present invention, backlash can be reduced by 3.
In order to obtain a step motor rotation of 6o0, the step angle accuracy of the step motor is doubled, and the driving force of the step motor is halved.In addition, the product is highly productive, as no capstan parts are required. A magnetic head positioning structure with good characteristics was obtained.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional magnetic head drive device, Fig. 2 is a developed view of a steel band, Figs. 3a and b are perspective views of a conventional steel band, and Figs. A perspective view of a steel band of a magnetic head drive device in an embodiment,
FIG. 6 is a developed view of the same steel band. 2... Upper magnetic head, 3... Lower magnetic head, 4... Upper arm, 9... Rotating shaft, 20... Steel band. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) Both ends of a steel belt α-wound around a rotatable drive motor shaft are fixed to an arm equipped with a magnetic head.
A magnetic head drive device that converts the rotation of the drive motor into linear motion of an arm, and records and reproduces tracks from the innermost circumference to the outermost circumference of a magnetic disk by rotating the drive motor at a rotation angle of 3,600 degrees or more. Convex (2) A magnetic head drive device according to claim 1, wherein a portion of the steel band is curved.