JPH0412549B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> This invention relates to improvements in magnetic disk cartridges.

<Prior art> The conventional structure of a magnetic disk cartridge is
As shown in the figure, a magnetic disk 2 is rotatably housed in a plastic cartridge case 1, and the center of rotation of the magnetic disk 2 is fixed and protrudes from an opening 1a formed on the bottom of the case 1. A disk hub 3 that also serves as an armature, and a rear end pressed against the inner bottom surface of the case 1 by a leaf spring 4,
It consists of at least a pair of latching levers 5 whose tips are pressed into contact with a flange portion formed on the periphery of the disk hub 3 to fix the disk hub 3 to the inner bottom surface of the case 1.

When the magnetic disk cartridge is not in use (as shown on the left side in the figure), the disk bub 3 is held and fixed in the case 1 together with the magnetic disk 2 by the spring elasticity of the latching lever 5. When the cartridge case 1 is loaded into the magnetic disk driver, the holding pin 5a of the latching lever 5 is pushed up by a release pin provided inside the driver, releasing the pressure on the disk hub 3. At the same time, a magnetic clutch provided at the tip of the spindle motor 7 engages with the lower end surface of the hub 3, and the magnetic disk 2 becomes rotatable.

However, with this cartridge configuration, the parts for clamping the magnetic disk 2 are large, and the assembly and
Adjustment takes a lot of time and costs are high.

In addition, since the spring 4 and the latching lever 5 are laminated in the thickness direction of the magnetic disk 2, the case 1 must be sufficiently thick, and the overall thickness must be kept thin considering the thickness of the magnetic disk 2. I couldn't convert it.

Furthermore, in this type of magnetic disk, the difference in dimension between the inner diameter of the opening 1a and the outer diameter of the disk hub 3 is large, so a large gap is formed between the two.
Although the magnetic disk 2 and disk hub 3 are fixed to the inner bottom of the case 1 by spring force, if handled roughly or shaken strongly, the disk hub 3 will wobble, and this wobbling can cause contamination due to wear. This may cause contamination such as dust or dirt to occur inside the case 1 due to the occurrence of contamination or the opening of gaps between the joints.

In this kind of magnetic disk cartridge,
Occurrence of contamination is a major problem.

In other words, when a magnetic disk is driven to rotate at high speed, the magnetic head floats with a gap of approximately 0.3 μm to 0.5 μm between itself and the magnetic disk due to its dynamic pressure, so fine dust particles are removed from the magnetic disk. If it enters the storage case, it may cause record destruction, head crash, or access error.

<<Object of the Invention>> The object of the present invention is to reduce the number of parts and achieve thinning, and also to eliminate looseness between the disk hub and the opening of the case, thereby preventing the occurrence of contamination.

<<Structure of the Invention>> In order to achieve the above object, the present invention provides a sleeve that is provided at the center of the upper surface of the case and has an engagement hole that expands at the top, and that engages with the sleeve in a tapered shape. A shaft is inserted through a mounting hole formed through the center of the disk hub, and the shaft is inserted between the lower end of this shaft and the upper end of the mounting hole, and the disk hub is urged upward to move the disk hub to the periphery of the bottom opening of the case. It is characterized by the provision of an elastic material for pressing.

<<Example>> FIG. 2 shows the overall structure of a magnetic disk cartridge according to the present invention, and FIGS. 3a and 3b show the structure of its main parts.

In the figure, 10 is a shallow container-shaped lower case made of synthetic resin, and 11 is an upper case that airtightly covers the upper opening of the lower case 10.

Disposed within the case are a disk hub 12 and a magnetic disk 13 whose center portion is fixed to the disk hub 12 via a mounting plate 14. Also,
A fixing plate 15 which also serves as an armature is integrally provided on the lower surface of the disk hub 12.

The fixing plate 15 has a flange 1 that comes into contact with the outer periphery of the opening 10a formed at the center of the lower case 10.
5a is formed. In other words, contrary to the conventional
When the disk hub 12 is lowered in the case, it is in a free state, and when it is raised, the flange 15a
has a structure in which it is fixed in contact with the lower surface of the lower case 10.

Further, a sleeve 16 is integrally provided in the center of the upper case 11 and has an engagement hole 16a that is enlarged at the top. A shaft 17 is inserted through the sleeve 16, and its head 17a is engaged in a tapered shape within the engagement hole 16a. The lower part of the shaft 17 is inserted into a mounting hole 12a passing through the center of the disk hub 12. Further, a flange 18 is integrated into the lower end of the shaft 17 and slides into contact with the inner circumference of the mounting hole 12a. A compression coil spring 19 is arranged on the outer periphery of the shaft 17 between the flange 18 and the upper part of the mounting hole 12a.

Due to the spring force of this spring 19, when the cartridge shown on the left side in FIG. 2 and as shown in FIG. 3 a is not in use,
The disk hub 12 is urged upward, and as a result, the peripheral flange portion 15a of the fixing plate 15 is forced into the opening 10.
The disk hub 12 and the magnetic disk 13 are fixed to the center of the case.

Note that 20 in the figure is a lid that covers the upper opening of the engagement hole 16a.

When the cartridge configured as described above is loaded into the magnetic disk drive as shown on the right side of FIG. 2 and FIG. It protrudes to press the lower end of the shaft 17 and raise it as shown by the arrow.

On the other hand, the magnetic clutch 22 provided on the periphery of the reference shaft 21 attracts the fixing plate 15 downward as shown by the arrow, and as a result, the flange portion 15a is attached to the lower case 1.
away from the bottom of the In this state, magnetic disk 13
can be rotated.

Note that the shaft 17 is located approximately at the center of the case before it is loaded into the magnetic disk driver.
Since the disc hub 12 is engaged with the outer periphery, the center of the disc hub 12 is almost perfectly centered, and when the reference shaft 21 engages with the mounting hole 12a of the disc hub 12, the center Positioning is performed with high precision and no loading errors occur.

《Effect of the invention》 This invention provides that when the cartridge is not in use,
The center of the disk hub is pressed upwards and fixed precisely in the center of the case, so there is no looseness caused by rough handling or strong shaking, and the positioning accuracy during loading is improved. can be increased.

Further, the present invention does not require complicated parts to fix the magnetic disk unlike conventional cartridges, and also eliminates the need for a release mechanism on the magnetic disk driver side. Therefore, the cartridge and driver mechanism can be extremely simplified, and since components are not stacked in multiple stages along the thickness direction, both the cartridge and driver can be made thinner.

[Brief explanation of drawings]

Fig. 1 is an explanatory cross-sectional view showing a conventional magnetic disk cartridge, Fig. 2 is an explanatory cross-sectional view of a magnetic disk cartridge according to the present invention, and Figs. 3a and b are cross-sectional views showing enlarged main parts. be. 10...Lower case, 11...Upper case, 1
2...Disk hub, 13...Magnetic disk, 1
6...Sleeve, 17...Shaft, 17a...Tapered head, 19...Compression coil spring.

Claims (1)

[Claims] 1 A magnetic disk rotatably housed in a cartridge case, a disk hub that fixes the center of rotation of the magnetic disk and protrudes from an opening formed in the bottom of the case, and a disk hub that engages and disengages from the disk hub. In the magnetic disk cartridge, the magnetic disk cartridge is provided with a clamp mechanism for fixing the disk hub to the cartridge case by engaging the magnetic disk hub, and the clamp mechanism is provided at the center of the upper surface of the case and forms an engagement hole that expands at the top. a sleeve; a shaft that tapers into engagement with the sleeve and is inserted through a mounting hole formed through the center of the disk hub;
A magnetic disk cartridge characterized in that an elastic member is provided between the lower end of the shaft and the upper end of the mounting hole to urge the disk hub upwardly and press the disk hub against the periphery of the bottom opening of the case.