JPS5823663B2 - Jixito Souchi - Google Patents

Description

[Detailed description of the invention] The present invention relates to a magnetic sheet device.

A typical magnetic sheet device rotates a flexible magnetic sheet stably along a back plate, and forms an air flow between the magnetic head that protrudes from the back plate toward the magnetic sheet. The specific structure is as described below.

That is, FIG. 1 is a sectional view of an embodiment of a conventional magnetic sheet device viewed from the side. In the figure, 12 is a motor fixed to the lower case 7, and 10 is a motor of the motor. A seat fixture fixed to the shaft 11, 9 a flexible magnetic sheet attached to the seat fixture 10, and 4 a back plate fixed to the upper surface of the lower case 7 to include the magnetic sheet. The back plate 6 and the lower case 7 form a magnetic sheet 90 and a rotating space 1.
7.

The magnetic head is fixed to the back plate 6, and the spherical part 8-1 facing the magnetic sheet 9 of the head protrudes from the surface of the back plate on the side of the magnetic sheet toward the rotation space 17. The surrounding area is sealed with adhesive or the like.

A lower filter frame 2 is fixed to the center of the back plate 6 as shown in the figure, and the upper filter frame 1 is arranged between the lower filter frame 2 and the filter 3 and the filter 4.
, a filter 5 is sandwiched therebetween and fixed to the lower filter frame 2 to form a filter unit.

Filters 3 and 5 are narrow-mesh filters that essentially serve as filters, and are used to remove dirt, dust, etc. from the air flowing in from the direction of the arrow in the figure, and filter 4 is a coarse-mesh filter. It forms an air flow path rather than an actual filter.

Further, the lower end filter frame 2 is provided with an inlet 2-1 for keeping the air flow rate constant.

Reference numeral 15 designates a printed board which is sandwiched and fixed between pillars 14, 14' fixed to the case 16 and pillars 13, 13' fixed to the lower plate I.

FIG. 2 is a schematic top view showing the structure of the lower case 7 in FIG. 1.

In the figure, 7-1 is 12 radial grooves formed equally,
7-2 is an outer circumferential groove connecting the outermost ends of the radial groove 7-1 with the outer periphery, and the radial groove 7-1 is further provided at the bottom of the outer circumferential groove 7-2.
A through hole 7-3 is provided at a location that is not in contact with the back plate 6, so that the air that has flowed in through the filter unit in the center of the back plate 6 flows out of the lower plate as shown by the arrow in the figure. It has a structure that

The surface 7-4 divided by the radial groove 7-1 is the sheet 9
In order to prevent cracking due to static electricity or the like, the surface is roughened by honing or the like to have a relatively finely uneven surface.

FIG. 3 shows in detail the state of the magnetic head and magnetic sheet 9 shown in the A-A sectional view shown in FIG. 1, and shows the center part of the slider 8-1 made of glass or ceramic. A head core 8-2 having a head gap 8-4 is embedded in a rectangular hole 8-1' drilled in the rectangular hole 8-1', and the head core 8-2 is attached to the slider 8-2 with an adhesive 8-3.
It is held at 1.

Furthermore, the surfaces of the slider 8-1 and the head core 8-2 that face the magnetic sheet 9 are polished into the same curved surface to form the head spherical portion 8.
-5 is formed (・ru.

When the magnetic sheet 9 is rotated by the motor 12 in the device described above, the gas near the magnetic sheet 9 is attracted to the magnetic sheet 9 due to its viscosity.

The magnetic sheet is rotated by centrifugal force and flows in the direction of the circumference of the magnetic sheet.

In other words, the airflow caused by 90 rotations of the magnetic sheet is the first
As shown by the arrows in FIG.

Flows outward between the seat 9 and the back plate 60,
It enters the outer circumferential groove 7-2 of the lower case I, and a portion flows out through the hole 7-3.

On the other hand, the air near the bottom of the magnetic sheet 9 similarly flows outward due to the rotation of the magnetic sheet 9.

It flows into the circumferential groove 7-2 and further enters the radial groove 7-1 and returns along the groove to near the center of the magnetic sheet.

The air flows between the magnetic sheet 9 and the lower case surface 7-4 and flows again along the magnetic sheet surface toward the outer periphery of the magnetic sheet.

In this way, the air circulates in the above embodiment, but the air near the magnetic sheet flows in a spiral in the same direction as the rotational direction of the magnetic sheet, as shown in FIG.

By the way, as mentioned above, the air flow between the back plate 6 and the magnetic sheet 90 caused by the rotation of the magnetic sheet 90 flows in the direction of the arrow shown in FIG. Since it hits the front half of the air, the air pressure in this area increases.

For this reason, the magnetic sheet 9 is pushed down along the magnetic head spherical portion 8-5.

Furthermore, on the rear surface of the magnetic head spherical portion 8-5 on the downstream side of the air flow, negative pressure is created due to the inertia of the air flow, so that the magnetic sheet 9
is drawn toward the back plate 6 along the magnetic head spherical portion 8-5.

The magnetic sheet 9 approaches the magnetic head 8 with a floating amount d on the downstream side of the air flow from the apex of the magnetic head spherical portion 8-5, so if the gap portion 8-4 of the magnetic head 8 is set at this position, the magnetic Needless to say, this is the most preferable method for recording and reproducing.

In such a magnetic sheet device, in order to perform high-density magnetic recording on the magnetic sheet 9, the floating amount d of the magnetic sheet 9 and the magnetic head 8 shown in FIG. 3 must be kept small and constant during the rotation of the sheet. However, as a method of reducing the floating amount d of the magnetic sheet 9, attempts have been made to make the magnetic head 8 further protrude from the magnetic sheet 9; As a result, the floating amount d hardly decreased, and instead caused the magnetic sheet 9 to vibrate.

Also, attempts have been made to reduce the floating amount d of the magnetic sheet 9 by reducing the radius of curvature R of the spherical portion 8-5 of the magnetic head, but this method makes it easier for the magnetic sheet 9 to come into contact with the magnetic head 8. This has the disadvantage of accelerating the wear of the magnetic sheet 9, but this is obvious from the fact that if the curvature of the spherical portion 8-5 of the magnetic head is extremely small, for example, in the shape of a needle, the magnetic sheet 9 will be immediately scratched and worn out. Will.

In view of the above-mentioned points, the present invention aims to provide a magnetic sheet device that makes it possible to reduce the floating amount d of the magnetic sheet 9, which was previously impossible, and to keep it constant while the sheet rotates. , Hereinafter, the present invention will be explained according to the drawings.

FIG. 4 is a sectional view of one embodiment of the magnetic sheet device according to the present invention, and its structure is almost the same as that in FIG.
What is different from the figure, and which is also an important part of the present invention, is that the flexible auxiliary sheet r is approximately similar in outer diameter, thickness, and flexibility to the magnetic sheet indicated by ``g'' as shown in Figure 4. The floating amount of the magnetic sheet 9' can be increased without changing the structure of the conventional magnetic sheet device shown in FIGS. 1 to 3. The purpose is to reduce d and keep it constant.

FIG. 5 is a sectional view taken along the line BB in FIG. 4, and is a detailed view showing the state of the magnetic sheet 9', the auxiliary sheet 9'', and the magnetic head l.

Embodiments of the present invention will be explained below with reference to FIGS. 4 and 5.

I will clarify.

In Fig. 4, the magnetic sheet 9' has a flexible auxiliary sheet 9'' superimposed on its lower side.Other than this, the structure and operation are similar to those of the conventional magnetic sheet shown in Figs. Since it is the same as the device, the explanation will be omitted.

The arrows shown in FIG. 5 indicate the air flow between the magnetic head 8 and the magnetic sheet 91, and the dotted line indicates the flow of air between the magnetic head 8 and the magnetic sheet 91, and the dotted line indicates the flow of air between the magnetic head 8 and the magnetic sheet 91, and the dotted line indicates the flow of air between the magnetic head 8 and the magnetic sheet 91. This is the floating shape of the magnetic sheet.

The magnetic sheet 9' shown in the embodiment of the present invention as shown in FIG. 5 overlaps with the flexible auxiliary sheet 9'' and rotates together, and the inertial force and centrifugal force of both sheets are combined to produce the same effect as in the case of a single magnetic sheet. Greater than inertial force and centrifugal force.

Therefore, when the airflow pushes up the magnetic sheet 9' in the direction away from the spherical part of the magnetic head on the front surface of the magnetic head on the upstream side of the airflow with respect to the OO' axis, a component of the sheet tension that tries to push it toward the magnetic head side conversely occurs. is larger, and compared to the conventional magnetic sheet device, the magnetic sheet 9' is closer to the magnetic head 8 on the front side of the magnetic head, and only the magnetic sheet γ is released from the auxiliary sheet 9'' due to negative pressure on the rear side of the magnetic head. and is attracted to the magnetic head side.

As a result, the floating amount d' of the magnetic sheet q from the magnetic head shown in FIG. 5 is greater than the conventional floating amount d.

This makes it possible to perform high-density magnetic recording and reproduction.

In addition, since the flexible sheets are stacked, the flexibility of the magnetic sheet is not impaired compared to simply making the magnetic sheet thicker. Even if the position of the magnetic sheet 9' moves slightly, the floating amount of the magnetic sheet 9' changes little and does not have any practical effect on high-density magnetic recording and reproduction.

Further, in the examples, the explanation was made using a single auxiliary sheet, but according to the inventor's experiments, it was found that the effects of the present invention can be sufficiently exhibited even when several auxiliary sheets are stacked one on top of the other. .

Note that FIG. 6 shows the state of the magnetic sheet 9' and the magnetic head when the auxiliary sheet 9'', which is less flexible than the magnetic strip, is superimposed, and as is clear from this figure, It can be seen that the magnetic sheet 9' pressed by the auxiliary sheet Cl//, which has little flexibility, has the disadvantage that it comes into contact with the apex of the spherical portion 8-5 of the magnetic head, accelerating wear.

As described above, the present invention enables high-density magnetic recording and reproduction by reducing and stabilizing the floating amount d of the magnetic sheet by simply superimposing a flexible auxiliary sheet on the magnetic sheet.

Note that by using a magnetic sheet that has become defective due to dropouts or the like as the auxiliary sheet, the present invention can be implemented without increasing the cost of the magnetic sheet device.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of an embodiment of a conventional magnetic sheet device as seen from the side, Fig. 2 is a top view of the carrier shown in Fig. 1, showing the structure of the lower case, and Fig. 3 is FIG. 1 is a state diagram showing the state of the magnetic head and magnetic sheet shown in the AA sectional view, FIG. 4 is a sectional view of one embodiment of the magnetic sheet device according to the present invention, and FIG. The state diagram of the magnetic head and magnetic sheet shown in the BB sectional view in the figure, Figure 6 is the state of the magnetic sheet and magnetic head when the auxiliary sheet with less flexibility is overlapped in Figure 5. It is a diagram. 1... Upper filter frame, 2... Lower filter frame, 3, 4, 5... Filter, 6...
...Back plate, 7...Lower case, 7-1...Radial groove, 7-2...
Outer circumferential groove, 7-3...through hole, 7-4...
Dividing surface, dan...Magnetic head, 8-1...
・Slider, 8-11... Hole, 8-2...
... Head core, 8-3 ... Adhesive, 8-4
...Head gap, 8-5...Head spherical part, 92g...Magnetic sheet, 9", 9"
'... - Auxiliary seat, 10... Seat mounting tool, 11... Motor shaft, 12...
...Motor, 13, 13', 14, 14'...
...Column, 15...Printed board, 16...
・Case, 17... Rotating space □ space.

Claims (1)

[Scope of Claims] 1. A flexible magnetic sheet arranged in isolation, a driving means for rotatably holding and driving the magnetic sheet, and a bag provided along the magnetic sheet. In a magnetic sheet device comprising a plate, a magnetic head approaches the magnetic sheet from the back plate side, and an air flow of a predetermined thickness is formed between the head and the sheet to perform magnetic recording and reproduction while making noise. . A magnetic sheet device, characterized in that a flexible auxiliary sheet having an outer diameter, thickness, and flexibility similar to that of the magnetic sheet is used by overlapping it on the surface of the magnetic sheet opposite to the head.