JPS6341647Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a magnetic disk device in which a drive pin is engaged with an engagement hole formed in a magnetic disk to rotationally drive the disk.

(Prior art) A drive pin is provided on a spindle hub that is rotationally driven by a motor, and the drive pin is engaged with an engagement hole formed at a position eccentric to the center of a magnetic disk (hereinafter referred to as "disk"). A magnetic disk device is known in which the disk is rotated by the rotation of the magnetic disk.

5 to 9 show conventional examples of magnetic disk devices. 5 and 6, a ring-shaped magnet 7 is fitted into a bottomed cylindrical spindle hub 6 that is fitted and fixed to the spindle 4, and the magnet 7 connects the disk hub made of a magnetic material. 5 and holds the disk hub 5 on a chucking head consisting of a spindle hub 6 or the like. The disk hub 5 integrally has a magnetic disk as a recording medium on its outer peripheral edge, but the magnetic disk is not shown. The spindle 4 is rotatably driven by a motor (not shown). Reference numeral 8 is a yoke that forms a path for the magnetic flux generated by the magnet 7.

Positioning of the disk hub 5 is performed by the drive pin 3. The drive pin 3 is supported by a leaf spring 2 fixed to the back surface of the spindle hub 6, and can swing in the axial direction, circumferential direction, and radial direction of the spindle hub 6 by the elasticity of the leaf spring 2. There is. As shown in FIG. 7, the disk hub 5 has a square hole 5a at the center and an engagement hole 5b at a position offset from the center, and the spindle 4 is fitted into the square hole 5a at the center. The drive pin 3 is inserted into the engagement hole 5b.
are now engaged. When the disk hub 5 is placed on the spindle hub 6, the drive pin 3 is pushed by the disk hub 5 and moves onto the spindle hub 6.
radially inward. When the spindle hub 6 rotates and the drive pin 3 reaches below the engagement hole 5b, the drive pin 3 is moved by the radially outward positioning force (biasing force) I of the spindle hub 6 based on the elasticity of the leaf spring 2. While pushing the disc hub 5 radially outward of the spindle hub 6, press the engagement hole 5b.
engages in the normal engagement position. This positioning force I causes two points on two sides a and b of the square hole 5a to come into contact with the spindle 4, thereby positioning the disk. Thereafter, when the spindle hub 6 is rotationally driven, the disk hub 5 is rotationally driven by the drive pin 3.

(Problems to be Solved by the Invention) According to the above-mentioned conventional magnetic disk device, as shown in FIGS. 8 and 9, when the disk hub 5 is placed on the spindle hub 6, The engagement hole 5b of the disk hub 5 is placed on the drive pin 3.
If the edge of the disc rides on the edge of the engagement hole 5b, the drive pin 3 may become hooked on the edge of the engagement hole 5b while being tilted outward in the radial direction of the disk, resulting in the disk being rotated with incomplete chucking. In this state, the positioning of the disk is incomplete, and the drive pin 3 may come off from the engagement hole 5b during rotation of the disk.

The purpose of the present invention is to prevent the edge of the engagement hole of the disk from getting caught when the drive pin is tilted, and to achieve stable chucking of the disk and reliable positioning of the disk in a magnetic disk device. Our goal is to provide the following.

(Means for Solving the Problems) The magnetic disk device of the present invention has a drive pin attached to a leaf spring, and the drive pin is arranged so that the front side is tilted downward with respect to the rotation direction of the disk. Features.

(Function) When the disk is placed on the spindle hub,
When the edge of the engagement hole of the disk hub rides on the drive pin, the plate spring that supports the drive pin bends and tilts. The drive pin is placed on the leaf spring with the front side tilted downward relative to the rotation direction of the disk, so the edge of the engagement hole of the disk hub rests on the drive pin as shown above. When the spindle hub is rotationally driven, the drive pin that is rotationally driven together with the spindle hub slips under the disk hub from the front side, and the drive pin rotates while riding on the edge of the engagement hole of the disk hub. Never. The spindle hub is approximately 1
When rotated, the drive pin advances into the engagement hole of the disk hub by the elasticity of the leaf spring, engages in the proper position of the engagement hole, and positions the disk hub by a predetermined positioning force.

(Embodiment) In FIGS. 1 and 2, a spindle hub 15 in the shape of a cylinder with a bottom is fitted and fixed to the spindle 10, and a ring-shaped magnet 20 is fitted into the spindle hub 15. A disk hub 19 made of a magnetic material is placed on the spindle hub 15, and this disk hub 19 is connected to the magnet 2.
0 is attracted to hold the disk hub 19 on the chucking surface 18 of the chucking head made of the spindle hub 15 or the like. A leaf spring 11 is attached to the lower surface of the spindle hub 15 with attachment screws 14, 14. Leaf spring 1
1 is made in an asymmetrical shape and has a part with a large spring constant and a part with a small spring constant.The part with a large spring constant is attached to the spindle hub 15 by the mounting screws 14, A shaft 13 is fixedly planted on the tongue portion 11a. axis 1
3 stands up through an escape hole 15a formed at the bottom of the spindle hub 15, and a drive pin 12 is attached to the upper end of the shaft 13. Drive pin 1
The upper end surface of 2 is located above the chucking surface 18 of the disk hub 19. Drive pin 1
2 can be formed, for example, by a ball bearing, in which case the inner ring of the ball bearing is connected to the shaft 13.
The outer ring of the ball bearing is engaged with the engagement hole of the disk hub 19.

A spacer 16 is interposed between the spindle hub 15 and the portion of the leaf spring 11 where the spring constant is small, and the leaf spring 11 is tilted.
The drive pin 12 is tilted by an angle θ so that the front side of the drive pin 12 is lowered with respect to the rotational direction of the disk indicated by an arrow in the figure. A stopper 1 is provided beside the drive pin 12 from the inner bottom of the spindle hub 15 on the rear side of the drive pin 12 with respect to the rotational direction of the disk.
7 is rising.

Now, disk hub 1 is placed on the tracking surface 18.
Let's say you put 9 on it. At this time, even if the edge of the engagement hole of the disk hub 19 happens to ride on the drive pin 12, the support shaft of the drive pin 12 is tilted by an angle θ and the drive pin 12 is placed in front of the drive pin 12 with respect to the rotation direction of the disk. Since the side is lowered, when the drive pin 12 rotates together with the spindle hub 15, the drive pin 12 slips under the disk hub 19. Therefore, there is no possibility that the disk hub 19 will rotate while being caught by the edge of the engagement hole of the disk hub 19 on the drive pin 12. When the drive pin 12 rotates and comes to the position of the engagement hole of the disk hub 19, the drive pin 12 is pushed into the disk hub 1 by the biasing force of the leaf spring 11.
9, the drive pin 12 attempts to swing outward in the radial direction of the disk based on the elasticity of the leaf spring 11, and this becomes a positioning force to position the disk.

Note that since the shaft 13 of the drive pin 12 is tilted by the angle θ, an angle θ is created between the shaft 13 and the stopper 17.
Since the inclination of disk hub 19 is given,
Contact between the drive pin 12 and the stopper 17 can be prevented in the chuck state. If the drive pin 12 and the stopper are in contact with each other, a frictional force will be generated between them and the positioning force will be reduced by that amount. Therefore, the elasticity of the leaf spring can be strengthened to obtain a larger positioning force. It is necessary to make it possible to do so. However, if the positioning force is too large, the disk hub may be rotated without the drive pin engaging with the proper engagement position of the engagement hole of the disk hub, or with the disk hub not resting on the specified chucking surface. There is. In this respect, according to the embodiment of the present invention, since no frictional force is generated between the drive pin 12 and the stopper 17, the disk can be reliably positioned with a relatively weak positioning force.

In addition, as described above, the drive pin 12 and the stopper 1
The fact that it is difficult for the drive pin 12 to come into contact with the drive pin 7 means that the distance between the two can be made very small. The amount of displacement can be limited to a very limited range by the stopper 17, and thus the amount of variation in the index position of the disk can be limited to a very small range.

In the embodiment shown in FIG. 3, a bent portion 21a is formed at the end of the leaf spring 21 that supports the shaft 13 of the drive pin 12, and this bent portion 21a is pressed against the lower surface of the spindle hub 15, so that the leaf spring 21 Tilt and hold
The driving pin 12 is inclined by an angle θ. Further, a stopper 23 that stands up on the side of the drive pin 12 is bent into an L-shape, and its base is attached to the lower surface of the spindle hub 15 together with the leaf spring 21 by a mounting screw 24. The other configurations and operations are the same as those in the previous embodiment, so their explanation will be omitted.

As shown in FIG. 4, as a configuration for supporting the drive pin 12 by the leaf spring while tilting the drive pin 12 by the angle θ, a bent portion 26 is provided at the intermediate portion of the leaf spring 26.
A is formed, and the inclination angle of this bent portion 26a is θ, and by supporting the shaft 13 of the drive pin 12 at this bent portion, the drive pin 12 is angled so that the front side is lowered with respect to the rotation direction of the disk. It may be tilted by θ.

(Effects of the invention) According to the invention, the drive pin is attached to the spring and is tilted so that the front side is lowered with respect to the rotation direction of the disk, so that the disk can be placed on the spindle hub. Even if the edge of the engagement hole of the disk happens to ride on the drive pin, when the drive pin rotates together with the spindle hub, the drive pin will slip under the disk,
It is possible to prevent the drive pin from rotating while being caught on the edge of the engagement hole of the disk. This allows stable tracking of the disk and reliable positioning of the disk.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of a drive pin portion showing one embodiment of the present invention, Fig. 2 is a bottom view of the above embodiment, and Fig. 3 is a longitudinal sectional view of a drive pin portion showing another embodiment of the present invention. FIG. 4 is a longitudinal sectional view of a drive pin portion showing still another embodiment of the present invention, FIG. 5 is a bottom view showing an example of a conventional magnetic disk device, and FIG. 6 is the above-mentioned conventional example. 7 is a plan view showing the disk positioning operation of the conventional example, and FIG. 8 is a perspective view of the driving pin for explaining the problems of the conventional example. FIG. 9 is a partially sectional front view of the same as above. 7b... Engagement hole, 11... Leaf spring, 12... Drive pin, 21... Leaf spring, 26... Leaf spring.

Claims (1)

[Scope of utility model registration request] In a magnetic disk device in which the disk is rotationally driven by engaging a drive pin with an engagement hole formed at an eccentric position with respect to the center of rotation of the magnetic disk, the drive pin is attached to a leaf spring, and the drive pin is attached to a leaf spring. A magnetic disk device characterized in that the drive pin is arranged so that the front side thereof is tilted downward with respect to the rotational direction of the disk.