JPH05250820A - Disk device - Google Patents

Abstract

PURPOSE:To stabilize the intermesh between a pinion for driving a head carriage and a rack. CONSTITUTION:The head carriage 12 and a rack part 13 are provided integrally, and the pinion 17 to be driven by a motor 14 is meshed with the rack 19. A leaf spring 18 is fitted to a motor holding part 21 for holding the motor 14, and the leaf spring 18 is fitted into a spring groove 13b of the rack part 13 so as to press the rack part 13 in the direction of Y1. The operating direction of pressing force of the leaf spring 18 is coincident with a shaft center of the pinion 17, so that the intermeshing state of the pinion 17 and the rack 19 is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device, and more particularly to a disk device for recording and / or reproducing data on a disk as a recording medium.

[0002]

2. Description of the Related Art FIG. 7 is a perspective view of a head carriage drive mechanism of a conventional flexible magnetic disk device (hereinafter simply referred to as "disk device"). The head carriage drive mechanism shown in the figure is disclosed in Japanese Patent Laid-Open No. 62-104272. In the figure, reference numeral 1 is a head, which is driven in the X direction (the same direction as the radial direction of the disc (not shown) of the recording medium) to access all the recording tracks of the disc to perform recording on the disc. / Play. The head 1 is fixed on the head carriage 2.

The head carriage 2 is made of a magnetic material and is fixed to a casing of the disk device.
Is movably supported in the X direction. Further, on the side opposite to the side where the guide shaft 3 of the head carriage 2 is supported, a rack member 5 having a rack 4 provided with sawtooth-shaped teeth downward in the drawing is fixed. ..
Further, a preload magnet 6 is provided near the lower part of the rack member 5 in FIG. The mutual attraction between the head carriage 2 made of a magnetic material and the preload magnet 6 urges the rack member 5 of the head carriage 2 and the rack 4 downward in the drawing, whereby the rack 4 and the pinion 7 move. The mutual engagement is ensured, and the backlash phenomenon that occurs in this portion (the idling phenomenon that occurs in the gap portion of the engagement portion between the rack and the pinion) is prevented.

The pinion 7 is provided at the tip of the drive shaft 8a of the step motor 8 fixed to the housing of the disk device. When the step motor 8 is rotationally driven, this rotational driving force is generated by the pinion 7. It is converted into a linear driving force in the X direction of the head carriage 2 via a well-known power transmission mechanism including the rack 4.

[0005]

FIG. 8 shows the relationship between the rack 4 and the pinion 7 of the head carriage drive mechanism of FIG. 7 and the relationship between them and the step motor 8. As described above, the rack 4 is urged downward in FIG. 8 by the preload magnet 6 for preventing the backlash phenomenon. In such a configuration, rotation of the step motor 8 causes the pinion 7 to rotate.
When is driven to rotate, microscopically, the teeth of the pinion 7 collide with the teeth of the rack 4. When the driving force for moving the rack 4 upward due to the product of the impact (gravitational acceleration) and the mass of the head carriage 2 at this time exceeds the attraction force of the preload magnet 6, the rack 4 moves. The rack 4 and the pinion 7 are moved away from each other as shown in FIG. After the rack 4 and the pinion 7 are separated from each other in this way, when the rack 4 comes into contact with the pinion 7 again, the rack 4 and the pinion 7 collide with each other, and the impact at this time shortens the life of both. Also, this impact causes rack 4
If the meshing parts of the pinion 7 and the pinion 7 are damaged, the meshing of the two becomes unreliable, and therefore the positioning accuracy of the head carriage 2 deteriorates and the performance of the disk device deteriorates.

Further, in this structure, as described above, the rack,
It is necessary to provide the preload magnet 6 to prevent the backlash phenomenon between the pinions and to make the head carriage 2 made of a magnetic material. Therefore, synthetic resin or the like, which is suitable for mass production and is lightweight, cannot be applied to the head carriage 2.
Therefore, the weight of the head carriage 2 becomes relatively large,
In order to drive the head carriage 2, a step motor 8 having a correspondingly large capacity is required. If the capacity of the step motor 8 is large, it is necessary to increase the driving torque accordingly, and thus it is necessary to increase the driving current, the voltage, and the like. Therefore, there is a problem that it becomes a barrier to downsizing, weight saving and power saving of the disk device.

Further, in order to attract the heavy head carriage 2, a powerful preload magnet 6 is required. Since such a preload magnet 6 generates a strong magnetic force, magnetic leakage occurs when an aluminum housing is used to reduce the weight of the disk device, which causes noise and reduces the performance of the disk device. was there.

Further, in FIG. 8B, the rack 4 is pressed against the pinion 7 by the preload magnet 6, so that the drive shaft 8 is placed on the lower portion of the bearing 8b of the step motor 8 in FIG.
a is pressed. Therefore, the wear speed of this portion becomes relatively high, and the drive shaft 8a is inclined due to this wear. When the drive shaft 8a is tilted, the tip of the drive shaft 8a is displaced downward in FIG. 7, and the rack member 5 of the head carriage 2 is displaced downward in FIG. When the rack member 5 of the head carriage 2 is displaced downward in this way, the head carriage 2 is tilted about the guide shaft 3. Therefore, the head 1 is tilted, and the contact pressure with which the head 1 contacts the disk of the recording medium is biased depending on the position on the contact surface, and normal recording / reproduction cannot be performed on the disk by the head 1.

In order to solve the above problems, the drive shaft of the motor is made parallel to the rotary shaft of the disk, and a spring member provided on the carriage 2 side is used instead of the preload magnet 6 to mount the rack 4 on the rack 4. Pressing on the pinion 7 is considered.

However, in the structure in which the rack 4 is pressed by the spring member, the meshing position of the pinion 7 with respect to the rack 4 moves relative to the movement of the head carriage 2,
The pressing direction of the spring member often does not coincide with the meshing position of the pinion 7, and for example, when the pinion 7 meshes with the end of the rack 4, the rack 4 easily tilts, and the pinion 7 meshes with the center of the rack 4. Compared to the case, the pressing force from the rack 4 on the pinion 7 changes. Therefore, when the head carriage 2 is moved, there are problems such as deterioration of tracking accuracy and noise generation.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a disk device capable of improving the movement accuracy of the head carriage.

[0012]

According to the present invention, there is provided a head carriage which supports a magnetic head slidably contacting a magnetic disk and is slidably provided in a disk radial direction, and a rack which is integrally provided on the head carriage. In a disk device having a pinion that meshes with the rack and is provided on an output shaft of a motor and a motor base that supports the motor, an elastic member that presses the rack toward the pinion has a pressing direction of the pinion. It is characterized in that it is provided on the motor base side so as to coincide with the axis.

[0013]

Since the shaft center of the pinion and the pressing direction of the elastic member are always the same regardless of the moving position of the head carriage, the pressing force (preload) of the rack against the pinion becomes constant, improving tracking accuracy and preventing noise generation. ..

[0014]

1 to 5 show an embodiment of a disk device according to the present invention.

In each drawing, 11 is a head carriage mechanism of a flexible magnetic disk device (hereinafter simply referred to as "disk device"), which is generally a head carriage 12, a rack portion 13 provided on a side surface of the head carriage 12, and a head. A step motor (hereinafter simply referred to as "motor") 14 that drives the carriage 12 in the disk radial direction (X direction).
And consists of.

The head carriage 12 is a lower head 15a.
Has a lower arm 15 for supporting the upper head 16a and an upper arm 16 for supporting the upper head 16a, and is provided slidably in the radial direction (X direction) of the magnetic disk (not shown).

A rack portion 13 is integrally provided on the side surface of the lower arm 15. This rack portion 13 is a pinion 1
Rack groove 13a into which 7 is inserted, and leaf spring (elastic member)
A spring groove 13b into which 18 is inserted is formed parallel to the X direction. A rack 19 that meshes with the pinion 17 is formed on the side wall of the rack groove 13a. Since the leaf spring 18 presses the spring groove 13b in the Y ₁ direction, the rack 19
Is pressed toward the pinion 17 side by the spring force of the leaf spring 18 and meshes with the pinion 17 in a playless state. Incidentally, the pinion 17 is, as shown in FIG.
It is provided directly on a. The motor 14 is mounted on a motor base 20 fixed to a chassis (not shown),
It is fixed by the motor holding member 21. An annular mounting base 22 is mounted on the lower end of the motor 14, and the mounting base 22 is an arc-shaped hole 2 concentric with the drive shaft 14a.
2a and 22b are provided at intervals of 180 degrees. Arcuate hole 22
The a and 22b are fitted to the guide pins 23a and 23b standing upright from the motor base 20, and the meshing position of the pinion 17 with respect to the rack 19 can be adjusted.

The motor holding member 21 is fixed to a column 24 standing upright on the motor base 20 with screws 25, and presses and holds the mounting base 22 on the motor base 20. Figure 6
As shown in (A) to (C), the motor holding member 21 includes a flat plate portion 21a fixed to the column 24, and first and second bent portions extending in the longitudinal direction (X direction) on both sides of the flat plate portion 21a. It has 2nd arm part 21b, 21c and the contact part 21d bent from the rear part side of the flat plate part 21a. A hole 21e, into which the screw 25 is inserted, is formed substantially at the center of the flat plate portion 21a.

A T-shaped leaf spring 18 is fixed to the side surface of one arm 21b by caulking or the like. The leaf spring 18 has a pressing piece 18a extending downward and inclined laterally (Y ₁ direction). A hemispherical projection 18b is formed at the tip of the pressing piece 18a by half punching.

The arm portion 21b has a motor base 20 at the tip.
To the motor base 20. The other arm 21c also has a semicircular contact portion 21g that contacts the motor base 20.

In the motor 14, when the motor holding member 21 is fixed to the column 24 on the motor base 20 by tightening the screw 25, the abutting portions 21f and 21 of the arm portions 21b and 21c.
g contacts the mounting base 22, and the mounting base 22 is sandwiched between the motor base 20 and the mounting base 22. The leaf spring 18 is attached at a position where the pressing piece 18a coincides with the axis of the upper pinion 17 in the Y ₁ and Y ₂ directions, and is inclined in the Y ₁ direction.

Therefore, when the pressing piece 18a penetrates the arc-shaped hole 22a of the mounting base 22 and is fitted into the spring groove 13b of the rack portion 13 by mounting the motor holding member 21, the pressing piece 18a of the leaf spring 18 is elastic. It deforms and presses the side wall of the spring groove 13b in the Y ₁ direction. The pressing piece 18a
A hemispherical projection 18b is projected on the
b contacts the side wall of the spring groove 13b, the pressing piece 18a
Even if is inclined, the pressing force (preload) by the leaf spring 18 is Y
Acts in _one direction.

Since the rack portion 13 is pressed in the Y ₁ direction by the pressing force of the leaf spring 18, the rack 19 is urged toward the pinion 17 side. Therefore, the rack 19 and the pinion 17 mesh without rattling.

When the pinion 17 is rotationally driven by the rotational driving force of the motor 14, the rack portion 13 moves in the X direction together with the head carriage 12, and the magnetic head 15 moves.
The seek operation of a and 16a is performed.

When the rack portion 13 slides in the X direction in this manner, the pressing piece 18a of the plate spring 18 provided on the motor holding member 21 relatively slides in the spring groove 13b of the rack portion 13. However, the leaf spring 18 is fixed to the fixed side, that is, the motor base 20 side, and is provided so that the pressing force of the pressing force 18a acts on the center line O (see FIG. 4) that coincides with the axis of the pinion 17. There is. Therefore, the rack unit 1
Even if 3 slides, the rack 19 does not tilt due to the spring force, and the pressing force of the rack 19 against the pinion 17 is kept constant. Therefore, the pinion 17 and the rack 19 maintain a stable meshing state, and the rotational force of the pinion 17 causes the rack 1 to rotate.
9 is reliably transmitted.

Therefore, the magnetic head 15 associated with the seek operation
Track deviations of a and 16a are prevented, the tracking accuracy can be further improved, and the pressing force of the rack 19 against the pinion 17 is constant regardless of the track position, so that noise during seek operation is also reduced.

Although the leaf spring 18 is attached to the motor holding member 21 in the above embodiment, the present invention is not limited to this, and the point is that it is provided on the fixed side of the motor base 20 or the like.

[0028]

As described above, in the disk device according to the present invention, since the shaft center of the pinion and the pressing direction of the elastic member are the same regardless of the moving position of the head carriage, the pressing force of the rack on the pinion becomes constant. Since the rack can be driven stably and the rack is prevented from tilting, tracking accuracy can be improved. Further, since the rack is driven in a stable meshed state by the rotation of the pinion, there is a feature that noise during a seek operation can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of a disk device according to the present invention.

FIG. 2 is a vertical sectional view showing a mechanism for pressing a rack portion.

FIG. 3 is a perspective view showing a motor and a motor holding member.

FIG. 4 is a plan view showing a main part of the present invention.

FIG. 5 is a side view showing a main part of the present invention.

FIG. 6 is a diagram showing a motor holding member.

FIG. 7 is a perspective view showing a main part of a conventional disk device.

FIG. 8 is a diagram showing a meshed state of a rack and a pinion.

[Explanation of symbols]

 11 Head Carriage Mechanism 12 Head Carriage 13 Rack 13a Rack Groove 13b Spring Groove 14 Motor 15 Lower Arm 16 Upper Arm 17 Pinion 18 Leaf Spring 19 Rack 20 Motor Base 21 Motor Holding Member 22 Mounting Base

Claims (1)

[Claims] 1. A head carriage that supports a magnetic head slidably contacting a magnetic disk and is slidable in the disk radial direction; a rack integrally provided on the head carriage; In a disk device having a pinion provided on the output shaft of the motor and a motor base supporting the motor, the motor so that the pressing direction of the elastic member pressing the rack toward the pinion side coincides with the axis of the pinion. A disk device, which is provided on the base side.