JPS593760A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To perform stably centering with high precision, by providing a centering chuck fixed by a spring to a disk holder position arranged to the rotation center part of a magnetic disk recording medium. CONSTITUTION:Disk holders 21 and 22 made of rigid bodies are provided to the rotation center part of the flexible magnetic disk recording medium 11. The centering chuck 24 is provided in an axially movable state at a hole part 22a provided at the rotation center position of the disk holer. The chuck 24 is energized toward the large-diameter opening part of a hole part 24a by a left spring body 25 fixed to the holder 22, and held in contact with the front surface of the disk holder 21. A magnet device 33 is embedded in a flange 32 provided to a rotating shaft on the side of the magnetic disk device body and the holder 21 is fixed to the flange 32 in the state of the chuck 24 is engaged with a center spindle 31.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention provides a highly practical magnetic disk device in which a flexible magnetic disk recording medium can be mounted in a magnetic disk device main body while reliably aligning the center of rotation. Regarding.

[Technical background of the invention and its problems]

In recent years, magnetic disk drives using flexible magnetic disk recording media, so-called floppy disks, which have excellent advantages such as being inexpensive and easy to handle, have become widespread. and,
Recently, the size of disk recording media has been reduced from the initial 8-inch type to 5-inch and 3-inch sizes.

However, in order to achieve the required performance as a recording medium when achieving this miniaturization, it is necessary to have a certain amount of storage capacity. Efforts are being made to increase the signal recording density itself. However, when attempting to increase the density of recording tracks in this manner, the rotational center of the disk recording medium must be accurately aligned to prevent the magnetic head from off-tracking the disk recording medium that is being rotated. It is extremely important to attach it to the main body. However, since the rotational center positioning accuracy in the conventional apparatus is not so good, there is a problem in that the conventional technique cannot be applied as is.

That is, in the conventional apparatus, for example, as shown in FIGS. 1(a) and 1(b), a hole 2 is provided at the center of a flexible magnetic disk recording medium 1, and a pair of disk holders 3, 3 are inserted through this hole 2. By fitting 4, the recording medium 1
At the same time, the recording medium 1 is held between the holders 3 and 4 and mounted. However, since the disk holders 3 and 4 are rigid bodies, there is a problem in that if the recording medium 1 is misaligned, the flexible recording medium 1 may be bent when sandwiched. Moreover, in this case, the accuracy of alignment of the rotational center of the recording medium 1 is influenced by the hole 2 provided in the flexible recording medium 1 itself, and the error is generally said to reach several tens of μm to several hundred μm. There were problems, and therefore, it was not suitable for center alignment for the high track density mentioned above.

Conventionally, for example, as shown in FIG. 2, a rigid holder 5 is provided at the center of the magnetic disk recording medium 1 itself, and two holes 6& are provided in the holder 5 for centering and rotational driving.

It has also been proposed that the rotational center of the recording medium 1 is aligned by fitting protrusions 1ja and 8b provided on the spindle 7 into the spindle 6b, respectively. However, for the plurality of recording media 1, the holes 6a, 6b and the protrusions 8m, 8b
It is extremely difficult to accurately determine the positional relationship between the two. Also, the recording medium 1 is placed on the spindle 7.
When the recording medium 1 is installed, there is a problem in that it is difficult to keep the distance from the spindle 7 to the recording surface of the recording medium 1 constant due to its structure. In other words, even if such a structure is adopted, there are some problems in terms of center positioning accuracy and other points when attempting to miniaturize and increase the density of the recording medium 1 described above. Therefore, in order to reduce the size of the magnetic disk recording medium 1, there has been a strong desire to develop a technique that can precisely align the center of rotation of the recording medium 1 and mount it in the main body of the apparatus.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and its purpose is to stably and reliably align the center of rotation of a flexible magnetic disk recording medium with high precision, thereby improving the performance of a magnetic disk device. It is an object of the present invention to provide a highly practical magnetic disk device with a simple configuration that can be attached to a main body.

[Summary of the invention]

The present invention provides a centering chuck that is provided with a disk holder at the center of rotation of a flexible magnetic disk recording medium, and has a hole in the shape of a funnel at the center of the disk holder so as to be movable in the axial direction. The centering chuck is biased toward the large-diameter opening end of the hole by a spring body fixed to the disk holder, and the magnetic disk drive main body has a center that fits into the hole of the centering chuck. The disc holder is provided with a spindle and a magnetic device which is provided integrally with the spindle and tightly fixes the disc holder by magnetic force.

〔Effect of the invention〕

Therefore, according to the invention, a centering member consisting of a rigid body,
The rotational center of the magnetic disk recording medium can be positioned with high precision and reliability by fitting the spindle with the spindle. In addition, by moving the centering shaft in the axial direction, the disk holder is maintained in a centered position by fitting with the spindle, and the disk holder is positioned relative to the spindle and tightly fixed by magnetic force. be able to. Therefore, it is possible to easily position the magnetic disk recording medium with respect to the main body of the magnetic disk drive with high precision, and it is a great help in increasing the density of the recording track and downsizing the recording medium. A great effect can be achieved.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIGS. 3(a) and 3(b) show the structure of a disk cassette according to an embodiment, in which a flexible magnetic disk recording medium 1 is rotatably housed in a cassette case 12. FIG. The cassette case 12 is provided with a long hole 13 that exposes a rotation axis of the magnetic disk recording medium 11, which will be described later, and also exposes a part of the recording surface of the recording medium 1. This elongated hole portion 13 is selectively opened and closed by a lid 14 movably provided on the case 12, and the lid 14 is connected to the cassette case 12.
A spring body 15 provided between the elongated hole portion 1
3 is biased to a position where it is closed. still,
In the figure, reference numeral 16 denotes a guide groove provided on the upper surface of the case 12 for regulating the movement of the lid 14. In this way, the magnetic disk recording medium 1 is housed in the cassette case 12 in a dust-proof manner.

Note that the lid body 14 is designed so that when the cassette case 12 is loaded into a cassette holder (not shown) of the main body of the apparatus,
It is slid against the spring body 15 by coming into contact with a locking piece provided on the holder. As a result, when the case set case 12 is attached to the main body of the apparatus, the elongated hole portion 13 is opened. A magnetic head (not shown) is opposed to the recording medium 11 through the elongated hole portion 13, and magnetic recording and reproduction of signals is often performed on the recording medium 11 which is rotationally driven.

By the way, the magnetic disk recording medium 1 housed in the cassette case 12 as described above is installed in the main body of the apparatus as follows.

As shown in FIGS. 4(a) and 4(b), the flexible magnetic disk recording medium 11 is provided with a rigid disk holder 21, 22 at its center of rotation.

The disk holders 21 and 22 are integrated with the recording medium 1 by inserting the edges of the center of rotation of the recording medium 11 from both sides and fixed by screws 23. A hole 22m having a slightly larger diameter than the hole 21h of the disk holder 2 is provided at the center of rotation of the disc holder 22, and a centering chuck 24 is provided so as to be movable in the axial direction of the hole 22a. It is being This centering chuck 24 is made of a rigid body, and has a large diameter tapered hole 24m in the direction toward the hole 21m at its center of rotation. The plate spring body 25 fixed to the holder 22 urges the large diameter opening of the hole 24g so that the disc boulder 21 is held in contact with the upper surface of the disc boulder 21. The leaf spring body 25 is, for example, as shown in FIG. Groove 25c
It has been established. The spring force acting on the centering chuck 24 is adjusted by the cut groove 25a. By adjusting the width W of the portion that functions as the tab spring body, the spring force is set appropriately. In addition, 26 in the figure is the entire back side for integrally fixing the leaf spring body 25 to the disk holder 22.

On the other hand, a rotating shaft connected to a disk rotating mechanism is provided on the magnetic disk device main body side. This rotation axis is
A center spindle 31 with a chi-shaped tip is provided at the center of rotation, and a flange 32 is provided at the base of the center spindle 31. A magnet device 33 is embedded in this flange 32 . When the recording medium 11 housed in the cassette case 12 is loaded into the main body of the apparatus, this magnet device 33 magnetically moves the disk holder 21 on the lower side with the centering chuck 24 fitted to the center spindle 31. Pull with force and perform the above 7 lunges 32
It is brought into contact with the top surface of the holder and fixed tightly.

The tapered surface of the center spindle 31 and the flange 32
The distance from the top surface of the magnetic recording medium 11 is set to be slightly longer than the distance between the bottom surface of the disk holder 21 and the tapered surface of the centering chuck 24, so that recording can be performed as shown in FIG. 4(b). When the medium 11 is mounted on the mounting main body, the lower surface of the disk holder 21 is tightly fixed to the upper surface of the flange 32, and the center spindle 31
A centering lever 24 fitted to the tip of the plate spring body 25 is lifted in the axial direction against the leaf spring body 25. In addition, the centering wheel 24 and center spindle 3
It goes without saying that each of the tenor planes of No. 1 is set at the same chi A angle.

According to this apparatus having such a centering mechanism, when the cassette case 12 is loaded into the apparatus main body, the center of rotation of the magnetic disk recording medium 11 is accurately aligned by fitting the centering chuck 24 to the center spindle 31. That will happen. Then, by moving the centering chuck 2 in the axial direction,
Maintain the fitted state with the center spindle 3, and
The lower surface of the disk holder 21 is closely fixed to the upper surface of the seven flange 32 by magnetic force while maintaining the aligned center of rotation, making it possible to determine the mounting position with high precision.

Therefore, it is possible to precisely define the positional relationship of the magnetic disk recording medium 1 with respect to the main body of the recording device and to mount it, and the main body of the recording device always performs magnetic recording and reproduction of signals in a stable state. becomes possible. Therefore, even when the recording medium 11 is made smaller and its recording track density is increased, there is no problem caused by the deviation of the center of rotation as in the prior art. Furthermore, as described above, the configuration is simple, so it is highly versatile and has extremely high practical advantages. Furthermore, since the position of the disk surface as well as the center of rotation can be defined with high precision, effects such as stable and uniform mounting on the main body of the apparatus can be achieved.

As described above, according to the present invention, since it is possible to provide a centering type with a simple structure, it is possible to easily miniaturize the disk recording medium and to make it into a cassette that is housed in the cassette case 12 and has a dust-proof structure. Many practical effects can be achieved, such as improved handling properties.

However, the present invention is not limited to the above embodiments. For example, the centering chuck 24 and the center spindle 3
The shape of the fitting portion with the plate spring 25, that is, the shape of the square, etc., may be determined according to the specifications, and the shape of the leaf spring body 25 is not particularly limited either. Other disk recording media 11
The size etc. of the K may be determined according to the specifications.
It can be applied in the same way. In short, the present invention can be implemented with various modifications without departing from the gist thereof.

[Brief explanation of the drawing]

Figures 1 (a), (b) and 2 are diagrams for explaining the center positioning of a disk recording medium in a conventional device, and Figures 3 (a) and (b) are diagrams for one embodiment of the present invention. A diagram showing the configuration of such a disk cassette, FIG. 4 (aλ(b)
5 is a diagram showing the configuration of main parts of the device of the same embodiment, and FIG. 5 is a diagram showing the shape of the leaf spring body in the same embodiment. 11... Flexible magnetic disk recording medium, 12...
Cassette case, 21.22... Disc holder, 2
3...screw, 24...centering chuck 25.
... Leaf spring body, 31 ... Center spindle, 32.
...Flange, 33... Magnet device. Applicant's Representative Patent Attorney Takehiko Suzue Ward 1 Figure 2 Figure 3

Claims (1)

[Claims] The magnetic disk recording medium consists of a flexible magnetic disk recording medium and a magnetic disk device body to which the magnetic disk recording medium is attached and performs magnetic recording and reproduction of signals.
a disk holder provided at the center of rotation; a centering chuck provided at the center of the disk holder so as to be movable in the axial direction; a spring body that biases the centering chuck toward the large-diameter opening end of the hole; a spindle, a magnet device that is provided integrally with the center spindle and positions the disk holder by magnetic force and fixes it tightly on the center spindle; and a magnet device that is rotationally driven to rotate the magnetic disk recording medium. What is claimed is: 1. A magnetic disk device comprising: a rotation mechanism for rotating a magnetic disk;