JPH0263272B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a floppy disk drive (hereinafter referred to as
FDD), the magnetic head is located on the outermost track 0, 0 of the magnetic disk (hereinafter referred to as TRO).
The present invention relates to an alignment adjustment method for properly positioning and adjusting the head carriage, and more specifically, relates to an alignment adjustment method for a type of FDD in which the head carriage is transferred by the forward and backward movement of a screw shaft that is screwed to the rotor of a step motor for moving the head carriage. .

[Background of the invention]

Generally, in an FDD, it is necessary to perform alignment adjustment so that the magnetic head is accurately positioned at the outermost TRO of the magnetic disk, but this adjustment is extremely complicated and requires skill and time.

For example, when the rotation of a step motor is transmitted to a head carriage via a steel belt or screw shaft, the step motor is excited with a phase holding voltage so that the rotor of the step motor is in a stopped state. In this situation, the entire step motor is rotated slightly to position the magnetic head above the TRO, but it is difficult to rotate the entire step motor slightly.
Furthermore, when the screws were tightened after adjustment, the position of the magnetic head was slightly changed by, for example, about 10 μm due to the tightening force of the screws.

For this reason, even after tightening the screws, the adjustment must be made several times to ensure that the magnetic head is in the correct position, resulting in extremely poor workability. Also,
As the density of magnetic disks increases, adjustment becomes even more troublesome, and it has been difficult to perform reliable alignment adjustment using the above-mentioned adjustment methods.

[Purpose of the invention]

Therefore, an object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide a method for easily and accurately adjusting alignment.

[Summary of the invention]

The above-mentioned object of the present invention is to provide a type of FDD in which a head carriage is transferred by a screw shaft screwed onto the rotor of a step motor, in which the screw shaft is first rotated in a certain phase relative to the fixed rotor. The magnetic head is moved forward and backward by a minute amount, and the magnetic head is positioned at TRO. In this state, the screw shaft is fixed with a set screw so that it cannot rotate. After that, the position of the magnetic head displaced by the tightening force of this set screw is determined. This is accomplished by adjusting an adjustment screw that tilts the step motor by a small amount, the details of which will become clear from the following examples.

[Embodiments of the invention]

The drawings all show an FDD according to an embodiment of the present invention, and FIG. 1 is a perspective view showing the main parts of the step motor and head carriage, and FIG. 2 is a partially cutaway plan view of the main parts to explain the adjustment method. be.

As shown in FIG. 1, in the FDD of this embodiment, the head carriage 1 is mounted along a guide rod 3 so that the magnetic head 2 mounted on the head carriage 1 can be moved along the radial direction of a magnetic disk (not shown). It is installed so that it can be moved in a straight line.

A step motor 4 is provided on the radially outward side of the magnetic disk from the head carriage 1.
In this step motor 4, when a rotor (rotating body) 5 rotates without moving in the axial direction, a screw shaft 6 screwed onto the central axis of the rotor 5 protrudes or retreats.

The screw shaft 6 extends parallel to the guide rod 3, and a locking member 8 is inserted into a groove 7 formed in the head carriage 1 and prevents rotation of the screw shaft 6 at its tip. The tip is fixed to a receiving plate 9 fixed to the head carriage 1.

The head carriage 1 is urged outward in the radial direction of the magnetic disk by a tension spring 10, so that the step motor 4 (rotor 5) rotates in a direction to project the screw shaft 6 toward the head carriage 1. Then, the receiving plate 9 is pushed by the tip of the screw shaft 6, and the carriage 1 moves linearly inward in the radial direction of the magnetic disk, and when the step motor 4 (rotor 5) rotates in the opposite direction, it is retracted. The receiving plate 9 is attached to the tension spring 1 against the tip of the screw shaft 6.
The head carriage 1 is adapted to move linearly outward in the radial direction of the magnetic disk by following the magnetic disk while remaining in contact with it due to an urging force of zero.

Reference numeral 12 denotes a mounting plate fixed to the bottom plate of the casing 13 of the step motor 4, and has both wing parts 14 and 15, and holes 16 and 12 are formed in the wing parts 14 and 15, respectively.
17 and 23 are bored.

In FIG. 2, 18 is a chassis of the FDD main body, and the mounting plate 12 is attached to the chassis 18. That is, as shown in the figure, one wing portion 15 of the mounting plate 12 is tightly fixed to the chassis 18 by suitable fixing means such as fixing screws 19. Further, a retaining screw 20 is loosely fitted and inserted into the hole 16 of the other wing portion 14 of the mounting plate 12, and the tip of the retaining screw 20 is screwed into the chassis 18.
A compression spring (spring means) 21 is interposed between the head of the 0 and the mounting plate 12, and presses the mounting plate 12 in a direction in which it comes into close contact with the chassis 18. 24
is an adjustment screw which is screwed into the hole 23 of the wing portion 14 and has its tip abutted against the chassis 18. Therefore, in FIG. 2, the chassis 18 and the mounting plate 12 are shown to be completely in close contact and parallel to each other, but by rotating the adjusting screw 24, the wing portion 14 can be adjusted around the fixing screw 19 side. The mounting plate 12 can be tilted in a direction in which the side is slightly spaced apart from the chassis 18, and the degree of inclination of the mounting plate 12 to be substantially parallel to the chassis 18 can be varied.

Next, the effect of the above configuration will be explained.

During alignment adjustment, the transfer of the head carriage 1 is stopped with the magnetic head 2 positioned near the TRO of the magnetic disk. Next, the rotor 5 of the step motor 4 is excited and
In the fixed state, loosen the setscrew 11 and rotate the rear end of the screw shaft 6 with a screwdriver 22 or the like to move the screw shaft 6 forward or backward, and position the magnetic head 2 on the TRO. In this state, tighten the set screw 11 and tighten the screw shaft 6.
is made unrotatable. The position of the magnetic head 2 often shifts by about 10 μm due to the tightening force of the set screw 11, but this shift is corrected in the next adjustment process.

That is, by rotating the adjustment screw 24 after the first rough alignment adjustment, the mounting plate 12, that is, the entire step motor 4 is slightly tilted relative to the chassis 18, as described above.
As a result, the head carriage 1 connected to the screw shaft 6 of the step motor 4 moves back and forth by a very small amount, and the deviation of the magnetic head 2 from the TRO of about 10 μm described above can be easily reduced to a range of several μm or less. The finer the thread pitch of the adjustment screw 24, the more fine the adjustment can be made.

In order to make this adjustment even easier, the mounting plate 12 is kept in close contact with the chassis 18, and when adjusting by rotating the screw shaft 6, the magnetic head 2 is moved about 10 μm inward of the magnetic disk from the TRO. If the adjustment is made by shifting the mounting plate 12 to
The adjustment is made in the direction of separating and tilting the adjustment screw 24 from 8, and the rotation direction of the adjustment screw 24 is always constant, making the adjustment easy.

After that, the step motor 4 is driven to move the rotor 5.
When the screw shaft 6 is rotated clockwise or counterclockwise, the screw shaft 6 moves forward and backward, and the head carriage 1 moves in a straight line following this movement.Thereby, the magnetic head 2 is accurately aligned with the desired track on the magnetic disk and the data can be read. Read/write is performed.

〔Effect of the invention〕

As described in detail above, the present invention consists of the first adjustment step of rotating the screw shaft and the second adjustment step of slightly tilting the step motor using the adjustment screw. The first adjustment process only requires adjustment within a certain range, and there is no need to retry as many times as in the past, and the second adjustment process allows for minute adjustments, which are as simple as simply turning an adjustment screw. Since the magnetic head is finely adjusted and positioned by operation, accurate alignment adjustment can be performed extremely efficiently and without requiring any skill, and it can easily accommodate higher track densities, so its value is enormous. .

[Brief explanation of the drawing]

The drawings all relate to embodiments of the present invention; FIG. 1 is a perspective view of the main part, and FIG. 2 is a plan view of the main part for explaining the adjustment method. 1...Head carriage, 2...Magnetic head,
3... Guide rod, 4... Step motor, 5
...Rotor, 6...Screw shaft, 7...
Groove, 8... Rotating member, 9... Receiving plate, 10...
... tension spring, 11 ... set screw, 12 ... mounting plate, 13 ... casing, 14, 15 ... wing section,
16, 17, 23...hole, 18...sash, 1
9... Fixing screw (fixing means), 20... Holding screw,
21... Compression spring, 22... Driver, 24...
…Adjustment screw.

Claims (1)

[Scope of Claims] 1. A screw shaft screwed onto the rotor of a step motor, a rotation preventing member for preventing rotation of the screw shaft, and a stop for fixing the screw shaft to the rotation prevention member. a screw, a head carriage that is always in contact with the tip of the screw shaft by the tension of a tension spring and that is equipped with a magnetic head and moves in the forward and backward directions of the screw shaft; and a mounting plate that is fixed to the casing of the step motor. , a fixing means for fixing one end of the mounting plate to the chassis of the drive device main body; an adjustment screw screwed onto the mounting plate at the other end of the mounting plate and having its tip abutted against the mounting plate; and the adjustment screw. and a spring means for pressing the mounting plate toward the chassis side on the side where the step motor is provided, and the screw shaft is rotated with the set screw loosened and the rotor of the step motor being energized and held so as not to rotate. move the magnetic head forward and backward, and move the magnetic head approximately on tracks 0 and 0 of the magnetic disk.
a first adjustment step in which the step motor is moved by a minute amount by rotating the adjustment screw to slightly change the degree of inclination of the casing that is substantially parallel to the chassis after tightening the set screw; 1. A method for adjusting alignment of a floppy disk drive, which further comprises a second adjustment step of finely adjusting the position of the magnetic head.