JPH03272061A - Magnetic head positioning mechanism of flexible magnetic disk device - Google Patents

Abstract

PURPOSE:To precisely position the magnetic head and to manufacture an FFD of high track density at a low cost by forming a needle of a magnetic head positioning mechanism of a lead screw type to a movable type. CONSTITUTION:A needle 5 is detained by a guide groove 8 on a screw 2, and when the screw 2 rotates by a stepping motor 1, the needle 5 moves forward and backward, and in connection therewith, a carriage 4 moves forward and backward along a guide rail 3, and a magnetic head placed on the carriage 4 is positioned roughly. When the needle 5 is swung by driving a rotary voice coil motor 9, the needle 5 becomes a lever by setting a contact of the needle 5 and the screw 2 as a supporting point, and the supporting point 10 moves minutely. In this case, since the supporting point 10 is fixed to an arm stretched from the carriage 4, the minute motion of the carriage 4 is attained. In such a way, positioning can be executed with high accuracy, and by using a fundamental design and many constitution parts in common, an FDD of high track density is manufactured at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head positioning method for a flexible magnetic disk device that records or reproduces information at high density.

[Conventional technology]

In recent years, in the field of electronics, devices have become smaller and the amount of information has increased, and magnetic storage reproducing devices are also being made smaller and have larger capacities. All to achieve small size and large capacity! Recording density has also improved dramatically, with fixed magnetic disk drives (HDDs) exceeding 2,000 TPI being announced, and flexible magnetic disk drives (FHDDs) exceeding 2,000 TPI.
DD) can also be reduced to 1.0OO by using optical means.
Things that exceed TPI have been announced.

For existing high trunk density FDDs (over 400 TPI), special high-speed positioning devices such as linear voice coil motors or ordinary positioning devices (13
This is dealt with by placing a positioning device for fine movement such as a piezoelectric actuator on top of the movable part (5 TPI or less).

[LIFL TO BE SOLVED BY THE INVENTION] In any of the methods described above, since the positioning mechanism is significantly different from the open-loop control positioning mechanism of a normal FDD, it is necessary to review the basic design of the device itself, and many configurations are required. There was a problem that parts could not be shared with normal FDDs.

Therefore, this invention simplifies the arrangement and configuration of the positioning mechanism for fine movement, and enables high-precision positioning using just a few parts in a normal FDD, thereby sharing the basic design and many of the components. The purpose is to manufacture an FDD with a high trunk density at a relatively low cost.

[Means to solve the problem]

In order to solve the above problems, in the device of the present invention, a small drive unit is disposed within the carriage of the lead screw one-type positioning mechanism, and the needle that presses the groove of the screw is slightly moved.

[Effect]

The angle formed between the needle and screw changes by operating the drive unit for fine needle movement. Due to this change, the positional relationship between the contact point of the needle and the screw and the fulcrum of the needle changes, and as the fulcrum of the needle moves back and forth, the carriage also moves back and forth to perform precise positioning.

Further, since the drive unit for fine needle movement applies the principle of a lever, the required power is relatively small, and a small unit can be used.

In this way, in the present invention, precise positioning of the head can be achieved by simply installing a small drive unit in the positioning mechanism that normally uses 9-way loop control and changing a few parts. It can be manufactured with only slight modifications to the FDD, allowing parts to be shared and development costs to be reduced.

〔Example〕

FIG. 1 shows the configuration of a positioning mechanism using a two-stage actuator according to the present invention, and FIG. 5 is an enlarged sectional view taken along the line X--X in FIG. 1.

FIG. 2 is an enlarged view of the contact point between the needle and the screw, and the presser spring 6 that presses the screw from above is omitted.

The needle 5 is restrained by a guide groove 8 on the screw 2. When the screw 2 is rotated by the stepping motor 1, the needle 5 moves back and forth, and accordingly, the carriage 4 moves back and forth along the guide rail 3, and the carriage 4 moves back and forth along the guide rail 3. A magnetic head placed above is roughly positioned. At this time,
Assume that the position of the needle 5 is as shown in FIG. 3(a). When the rotary voice coil motor 9 is driven and the needle 5 is swung in the direction of arrow C as shown in FIG. moves slightly in the direction of the arrow in the figure. Here, since the fulcrum 10 is fixed to an arm extending from the carriage 4, fine movement of the carriage 4 is achieved.

FIG. 4 shows the restraining portion of the screw 2 and needle 5 as seen from the direction of arrow B in FIG. The guide groove 8 has an elliptical cross section as shown in the figure, and allows the prying action of the needle as shown in FIG. Also, needle 5
is pressed in the direction of the arrow A by the presser spring 7, thereby suppressing the occurrence of wobbling between the guide groove 8 and the guide groove 8.

Normally, the coarse movement due to the loop control positioning mechanism is approximately 18
Since the pitch is 8μrn, the width of slight movement is 1100μm.
is sufficient. The distance between the contact between the needle 5 and the screw 2 and the fulcrum 10 is set to 115 to 1/I O of the distance between the contact and the rotary voice coil motor 9.
The movable width of the rotary voice coil motor 9 is ±1+u
This is sufficient, and because the lever principle requires less power, it is possible to make the device thinner and more compact.

Furthermore, the driving section of the needle 5 is not limited to the rotary voice coil motor as shown in this embodiment, but a piezoelectric actuator or the like may also be used.

Furthermore, by stopping the drive section at a suitable reference point, the actual positioning mechanism becomes equivalent to a positioning mechanism under normal loop control. That is, high 1 rack density F
Although it is a DD, it can easily have read/write compatibility with a normal FDD.

〔Effect of the invention〕

As explained above, according to the present invention, by making the needle of a conventional lead screw type magnetic head positioning mechanism movable, precise positioning of the magnetic head is possible. You can make FDD.

Further, read/write compatibility with normal FDDs can be easily provided.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram for explaining the entire positioning mechanism according to the embodiment of the present invention, FIG. 4
The figure is an explanatory view showing the relationship between the guide groove and the needle, and FIG. 5 is an enlarged sectional view taken along the line XX in FIG. 1. 1... Stepping motor 2... Screw, 3... Guide rail, 4...
Carriage, 5... Needle 6.7... Holder spring, 8... Guide 4S 9... Rotary voice coil motor 10... Fulcrum. Figure 1 Figure 2

Claims (1)

[Claims] A lead screw having a guide groove, a stepping motor that rotates the lead screw, a carriage equipped with a magnetic head and restrained by a guide rail so that it can move in one direction, and converting the rotation of the screw into forward and backward movement of the carriage. In order to do this, in a lead screw type magnetic head positioning mechanism of a flexible magnetic disk device having the guide groove and a needle restrained by the carriage, the carriage is moved back and forth by a minute amount by driving the needle with a small drive unit. A magnetic head positioning mechanism for a flexible magnetic disk device, which is characterized by precisely positioning a magnetic head.