JPH02257482A - Magnetic sheet pack and magnetic sheet recording and reproducing device - Google Patents

Abstract

PURPOSE:To make a head touch excellent by providing a slanting surface inside a peripheral part of a window part of a protection case and generating a positive pressure or a negative pressure between a rotating magnetic sheet and this slanting surface. CONSTITUTION:When the slanting surfaces 12a and 12b opposite to a natural surface of the magnetic sheet 15 are provided to members to be elastically supported inside or from the peripheral part of at least one of the window parts 20 and 21 of the protection cases 12 and 13, the positive pressure or the negative pressure is generated between the rotating magnetic sheet 15 and these slanting surfaces 12a and 12b in accordance with the rotating direction. Thus, by utilizing these positive pressure and negative pressure, the magnetic sheet 15 is sucked up to be pressed against a magnetic head 24 so that the excellent head touch is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Public Expenses for Industrial Use> The present invention relates to a magnetic sheet pack and a magnetic rate recording/reproducing apparatus that can perform high-density magnetic recording and reproducing on one or both sides of a magnetic rate.

<Prior art> In recent years, imaging devices such as solid-state image sensors and image pickup tubes have been combined with recording devices that use magnetic sheets, which are inexpensive and have a relatively large storage capacity, as a recording medium, to take still images of subjects and store still image information. An electronic still camera system has been developed that records images on a rotating magnetic sheet and reproduces the images using a television recording system, printer, etc. The magnetic sheet used in this system is made by coating a magnetic material on a thin disc-shaped base material made of synthetic resin, so it is flexible and weak against mechanical deformation forces, and the surface is free from dust and dirt. If it adheres, it will interfere with the accuracy of recording and reproduction, so it is usually used in the form of a magnetic sheet pack housed in a protective case that cannot be easily deformed.

FIG. 12 is a partially cutaway perspective view of the front side of the magnetic rate pack, and FIG. 13 is a cross-sectional view taken along the line XI--XI. As shown in these drawings, the magnetic sheet pack 11 includes a protective case 14 consisting of an upper case 12 and a lower case 13 made of synthetic resin, and a flexible disk rotatably housed within the protective case 14. It is composed of a magnetic sheet 15 having a shape, a metal shutter 16 slidably attached to one side of the protective case 14, and the like. A center core 17 as a reinforcing member is provided in the center of the magnetic sheet 15.
This center core 117 is provided with a mounting hole 18 into which a rotational drive shaft of a recording/reproducing device is inserted.
The upper and lower surfaces of 7 are the openings 19 in the center of the upper and lower cases 12 and 13.
exposed to the outside. Further, a window 20 is opened in the upper case 12 into which a regulating plate 22 of a recording/reproducing device is inserted, and a window 21 into which a magnetic head 23 is inserted is opened at a corresponding position on the back side thereof. FIG. 13 shows these configurations in a sectional view taken along the line xi-xi in FIG. 12. Furthermore, a stainless steel shutter 16 having a U-shaped cross section is slidably mounted to open and close these window portions 20 and 21.

<Problem that the invention seeks to solve> A magnetic sheet pack with such a configuration has dimensions.

Unified standards have been established for accuracy, etc., making it possible to use magnetic sheet recording and reproducing devices of various companies with compatibility.

However, there is no unified standard for magnetic sheet recording and reproducing devices, and each company has its own configuration.

Therefore, the shape and dimensions of the regulating plate 23 can be freely designed, and in place of the regulating plate 23,
As shown in Japanese Patent No. 9868, negative pressure may be used to perform head touch. That is, as shown in FIG. 14(a), inclined control members 25 and 26 are installed on the upstream and downstream sides of the magnetic head 24 to control the rotating magnetic rate 27.
Negative pressure is created between the two. When a negative pressure is generated, the magnetic sheet 27 is attracted to the control members 25 and 26 and comes into stable contact with the magnetic head 24, as shown in FIG. 14(b).

Since the regulation plate 23 or the control members 25, 26, etc. are used to obtain a head contact with the magnetic head, the quality of the head touch is determined by the selection of the means or its design, and this is due to the fact that the magnetic sheet This had a negative impact on pack compatibility. Recently, attempts have been made to increase the frequency band of electronic still cameras, and in this case, reliable head touch is required.

On the other hand, there is an increasing demand for double-sided recording for magnetic sheet packs as well. However, because magnetic sheet packs have different circumstances from 3.5-inch and 5.25-inch floppy disks, the double-sided recording technology for these floppy disks could not be applied. That is, as shown in Table 1, the magnetic sheet pack has a thinner medium and a smaller radius than 3.5-inch and 5.25-inch floppy disks, but the rotation speed is higher.

Furthermore, the area of sliding contact of the magnetic head used is also small. This means that the magnetic sheet used in magnetic sheet packs is much more flexible than that of floppy disks, so simply pressing the magnetic head against both the front and back sides of the magnetic sheet will not provide stable sliding contact. It means that. In addition, the area of sliding contact of the head - 1 *: Depends on the current standard, but since it is small, in a method such as double-sided recording on a floppy disk, in which the magnetic head is constantly in contact with the same location on the medium from both the front and back sides via a gimbal spring, The pressure per unit area becomes too high, which tends to cause wear and damage to the magnetic sheet.

Furthermore, as in the magnetic sheet recording and reproducing apparatus shown in FIG. 15 (Japanese Patent Application Laid-Open No. 62-1168, FIG. 1), magnetic heads 222 and 223 face each other with a small gap between them with a rotating magnetic sheet 221 in between. and pad 224 or 225
By pressing on the front or back side of the magnetic sheet 221,
There is also a method of sequentially contacting the magnetic head 222 or 223. However, this method has problems in that the mechanism for moving the pads 224, 225 is complicated and the sliding contact between the pads 224, 225 tends to cause wear.

The present invention has been made in view of the above-mentioned circumstances, and provides a magnetic sheet pack equipped with a means for obtaining a good head touch by cooperating with either a regulation plate or a control member, etc. It is something to do. Another object of the present invention is to provide a magnetic sheet pack that does not require a regulating plate or a control member, and is equipped with a means for obtaining a good head touch by itself. On the other hand, a third object is to provide a magnetic sheet recording/reproducing device which can perform double-sided recording/reproducing even on a magnetic sheet pack and has good head touch.

Means for Solving the Problems> The structure of the magnetic sheet pack of the present invention that achieves the above object is to rotatably store a flexible disk-shaped magnetic sheet in a protective case, and also to accommodate the protective case. In a magnetic sheet pack that performs magnetic recording and reproduction by opening windows at respective positions, and inserting a magnetic head through one of the windows and slidingly contacting the rotating magnetic sheet, the magnetic head is The present invention is characterized in that an inclined surface is formed on the inner side of the edge of the other window portion that is not inserted, which biases the rotating magnetic sheet against the magnetic head by positive pressure. Here, the sloped surface refers to a surface that is inclined with respect to a natural surface in a state where the magnetic sheet does not rotate and no external force acts on it, and between the surface that approaches the magnetic sheet as it moves downstream in the direction of rotation. A positive pressure is generated between the magnetic sheet and the magnetic sheet, and a negative pressure is generated between the magnetic sheet and the magnetic sheet as it moves downstream in the rotational direction.

The flexible magnetic sheet is urged and attracted to the magnetic head by such positive pressure and negative pressure, so that it makes good sliding contact with the magnetic head.

On the other hand, the magnetic sheet recording/reproducing device of the present invention which achieves the above object is provided with a flexible disc-shaped magnetic sheet mounted on a spindle motor that can freely rotate forward and backward, and with the magnetic sheet sandwiched between the spindle motors and the magnetic sheets separated by a small gap. A first magnetic head and a second magnetic head are disposed on both sides of the first magnetic head, and when the magnetic sheet rotates in one direction, negative pressure is generated on both sides of the first magnetic head in the circumferential direction, and the magnetic sheet a control member having an inclined surface that attracts the magnetic sheet toward the first magnetic head and generates a positive pressure when the magnetic sheet rotates in the other direction to push the magnetic sheet toward the second magnetic head. It is characterized by

Effect> If a surface inclined with respect to the natural surface of the magnetic sheet is provided on the inside of at least one edge of the window of the protective case, or on a member elastically supported from this, the rotating magnetic sheet and this Since positive pressure or negative pressure is generated between the magnetic sheet and the inclined surface depending on the direction of rotation, if this positive pressure or negative pressure is used, the magnetic sheet is attracted to the magnetic head and pressed against it, resulting in a good head touch. Similarly, in a magnetic sheet recording/reproducing device, the head touch is similarly stabilized by providing a control member that is inserted into the window of the magnetic sheet pack together with the magnetic head with a surface that is inclined with respect to the natural surface of the magnetic sheet. It happens.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. The embodiment shown in the figure relates to a magnetic sheet pack that urges the magnetic sheet 15 by positive pressure, and FIG. 1 is similar to XI in FIG.
This corresponds to the -XlI line cross section. That is, on the inside edge of the window 20 opened in the upper case 12, on the upstream and downstream sides of the magnetic head 24, there are inclined surfaces 12m and 12m, respectively.
2b is formed. Both of these inclined surfaces 12a and 12b approach the natural surface N (hereinafter referred to as free rotation surface N) when the magnetic sheet 15 does not rotate and is not subjected to any external force as it goes downstream. It is inclined. Which inclined surface θ1. There is no particular restriction on θ2, but it can be set to, for example, 0.5° to 5°. Also, its width W1. For W2, 2 to 4 words may be used. The inclined surfaces 12a and 12b generate positive pressure against the rotating magnetic sheet 15, but the range thereof is very narrow, so the inclined surfaces 12a and 12b are used as much as possible.

It is necessary to bring the terminal end of 12b close to the magnetic sheet 15,
Usually, the thickness is set to several tens of microns or less. However, it is fine as long as it comes into contact with the magnetic sheet 15, but if the pressure is applied more strongly than that, the magnetic sheet 15 will be plastically deformed, which is not preferable.

Incidentally, since the window portion 20 of the upper cover 12 complies with the standard in which a regulating plate is intended to be inserted, it is relatively large and the above-mentioned inclined surface 12a.

There is a possibility that the positive pressure generated by 12b will not be sufficient. Therefore, in this embodiment, the upstream side of the magnetic head 24,
Control members 25 and 26 are arranged on the downstream side, and these control members 25 and 26 are connected to the lower case 1 together with the magnetic head 24.
It was decided to insert it through the window 21 of No. 3. Therefore, the negative pressure due to the control member 25, 26 and the inclined surface 12a.

The magnetic sheet 15 is urged toward the magnetic head 24 and attracted by the positive pressure of the magnetic head 12b.

In the above embodiment, the inclined surfaces 12a and 12b are formed on the upper case 12.
Although it was formed integrally with the above, it may be formed as a separate piece. For example, as shown in FIG.
It may be attached to the inner side of the edge of 0. In addition, as a modification example, as shown in FIG. 2(e), the inclined surface 12
A coating material 30, 31 having abrasion resistance and low abrasion properties may be applied to the surfaces of m and 12b. Further, in the above embodiment, the inclined surfaces were provided on the upstream and downstream sides of the magnetic head 24, but the inclined surfaces may be provided on either the upstream side or the downstream side.

Next, a second embodiment will be described with reference to FIG. This embodiment utilizes negative pressure. That is, among the inside edges of the window portion 21 opened in the lower case 13, there are inclined surfaces 13 on the upstream side and the downstream side with respect to the magnetic head 24.
α.

13b is formed. This inclined surface 13a.

13b are all inclined so that they become farther downstream from the free rotation surface N of the magnetic sheet 15. These angles of inclination.

The width and the like may be the same as in the above embodiment. Control members 25 and 26 are inserted into the window portion 21 together with the magnetic head 24, and these control members 25 and 26, the inclined surface 13a,
The magnetic sheet 15 is attracted to the magnetic head 24 by the cooperation of the negative pressure generated by the magnetic sheet 13b. In this embodiment, as shown in FIGS. 2(a) and 2(b), wear-resistant and low-wear inclined members are installed in place of the inclined surfaces 13a and 13b. Similar properties may be imparted by coating.Furthermore,
In the above embodiment, the inclined surfaces 13a and 13b were provided on the upstream and downstream sides of the magnetic head 24, but if unnecessary,
Either one may be omitted.

Next, a third embodiment will be described with reference to FIGS. 4 and 5. This embodiment is adapted to support double-sided recording. That is, a flexible disk-shaped magnetic sheet 34 is housed between the upper case 32 and the lower case 33, and the upper case 32. Windows 35 and 36 are opened at corresponding positions in the lower case 33, respectively. Each window part 35, 36
A first magnetic head 37 and a second magnetic head 38 are inserted from the magnetic heads 37 and 38, respectively, and are opposed to each other with the magnetic sheet 34 interposed therebetween. Among the inside edges of the window portion 35 into which the magnetic head 37 is pushed, there are inclined surfaces 32 on the right and left sides of the drawing with respect to the magnetic head 37.
a, 32b are formed. Both of the inclined surfaces 32a and 32b are inclined so as to approach the free rotation surface N of the magnetic sheet 34 toward the left in the figure. In addition, there are inclined surfaces 33a on the right side and left side in the drawing with respect to the magnetic head 38 on the inner side of the edge of the window portion 36 into which the magnetic head 38 is inserted.

33b is formed. Both of the inclined surfaces 33a and 33b are inclined so as to move away from the free rotation surface N of the magnetic sheet 34 toward the left in the figure. Therefore, as shown in FIG. 4, when the magnetic sheet 34 is rotated so as to flow from the right to the left in the figure, the inclined surfaces 32a, 32b
At the same time, positive pressure is generated between the inclined surfaces 33m and 33m.
A negative pressure is generated between the Therefore, the magnetic sheet 34 is urged by positive pressure and attracted by negative pressure,
This results in stable sliding contact with the second magnetic head 38.

Conversely, as shown in FIG. 5, when the magnetic sheet 34 is rotated so as to flow from the left to the right in the figure, the inclined surface 3
2m and 32b, and at the same time, positive pressure is generated between the inclined surfaces 33m and 33b. Therefore, the magnetic sheet 34 is urged by the positive pressure and attracted by the negative pressure, and comes into stable sliding contact with the first magnetic head 37.

In this embodiment, in order to perform magnetic recording on both sides of the magnetic sheet 34, it is necessary to rotate the magnetic sheet 340 in the forward and reverse directions. This has the advantage that it is not necessary.

In the above embodiment, double-sided recording is also possible, but one of the magnetic heads may be omitted to perform single-sided recording. Of course, in this case as well, stable head touch can be obtained without the need for a regulating plate or the like.

Next, regarding the magnetic sheet recording and reproducing device of the present invention, the sixth
This will be explained with reference to the conceptual explanatory diagram shown in the figure. As shown in the figure, magnetic heads 127 and 128 are positioned on both sides of the magnetic sheet 126 with a slight gap between them, and on both sides in the circumferential direction with respect to one magnetic head 127 (circumferential direction with respect to the magnetic sheet 126). are provided with control members 129 and 130, respectively. These control members 129,
The surface of 130 facing the magnetic sheet 126 is an inclined surface 129
a.

It is 130a. The slanted surface here refers to a surface that is not parallel to but inclined to the free rotation surface N, which is assumed that no external force acts on the magnetic sheet 126. Both slanted surfaces 129a and 130a are shown in the figure. The slope approaches the free rotation surface N toward the right.

Now, when recording and reproducing are performed using the magnetic head 127 located below the magnetic sheet 126 in FIG. 6, the magnetic sheet 126 is rotated in the direction shown by the solid line arrow in the figure. Then, the inclined surfaces 129a and 130a are magnetic sheets 126''
The magnetic sheet 126 moves away from the magnetic sheet 126 as it moves in the direction of rotation, so negative pressure is generated between the two, and the magnetic sheet 126 bends as shown by the solid line in the figure, causing the magnetic head 1 to move away from the magnetic sheet 126.
It is attracted to the 27 side and comes into sliding contact with the magnetic head 127. On the other hand, when recording and reproducing are performed using the magnetic head 28 located above the magnetic sheet 126, the magnetic sheet 126 is rotated in the opposite direction to that described above, as shown by the dashed arrow in the figure. In this case, the inclined surfaces 129m and 130a approach the magnetic sheet 126 as they advance in the rotation direction of the magnetic sheet 126, so the inclined surfaces 129a.

A positive pressure is generated between the magnetic sheet 130a and the magnetic sheet 126, and the magnetic sheet 126 is bent as shown by the broken line in the figure, pushed toward the magnetic head 128, and comes into sliding contact with the magnetic head 128.

As shown in Part B, in the magnetic sheet recording/reproducing device of the present invention, by reversing the rotation direction of the magnetic sheet 126, the magnetic sheet 126 can be brought into sliding contact with either of the magnetic heads 127° 128, and thereby the magnetic sheet 126 Recording and reproduction can be performed on both sides of the sheet 126.

Next, specific embodiments of the magnetic sheet recording and reproducing apparatus are shown in FIGS. 7 to 11. As is clear from the above description, in the magnetic sheet recording and reproducing apparatus of the present invention, it is sufficient to provide a control member on at least one magnetic head side, but in the following embodiments, a control member is provided corresponding to both magnetic heads. A control member is provided to ensure head touch.

7 to 9 show an embodiment of a magnetic sheet recording/reproducing device, and as shown in the figure, a flexible disk-shaped magnetic sheet 131 is attached to a protective case 134 consisting of an upper case 132 and a lower case 133. It is rotatably stored in a magnetic sheet pack and is used in the form of a so-called magnetic sheet pack. In this magnetic seat back, the windows 132a and 133a into which the magnetic heads 135 and 136 are inserted are located in the upper case 132. This window 5132m, 13 is provided in the lower case 133.
A shutter 137 for opening and closing 3a is slidably attached. The magnetic heads 135 and 136 are inserted through these window portions 132m and 133a and are opposed to each other with a gap in between. Direction) 1 slit on each side
Control members 138, 139, 140, 141 are elastically supported via 32b, 132c, 133b, 133c, respectively. Here, the sleeves 132b, 132
The shapes of c, 133b, and 133c may be such that they cantilever support the control members 138 and 139 as shown in FIG. It may also be shaped like a letter-shaped support.

The control members 138, 139, 140, 141 are all attached to the upper case 132. It is integrally molded with the lower case 133. Each of these control members 138 to 141 is formed with an inclined surface having a shape as shown in FIG. 7. That is, the control members 138 located on both sides of the magnetic head 135
, 139 are respectively formed with inclined surfaces 138m and 139a that approach the free rotation surface N as they go leftward in the figure, and control members 140 and 141 located on both sides of the magnetic head 136 are respectively formed as shown in FIG. Sloped surfaces 140m and 141 that move away from the free rotation surface N toward the center left
m is formed.

Slope 138a, 139m, 140m, 1
The inclination angle of 41a may be different on the upstream side and downstream side, or may be different on the opposing side. The same applies to the length of the inclined surface.

However, for example, it is appropriate for the range of the inclination angle to be 7 degrees or less, and for the length of the slope to be from 1 earthquake to about 71 degrees. Control member 1
38, 139, 140° 141 are all brought close to the magnetic sheet 131 by control pins 142, 143, 144, and 145, as shown in FIG. biased in the direction.

In this state, each control member 138° 139, 140, 141
The closest distance between the magnetic sheet 131 and the free rotation surface N of the magnetic sheet 131 is set to several hundred μm or less. Control members 138, 13
Effective positive pressure between the inclined plane of 9°140.141.

This is to generate negative pressure to attract or push the magnetic sheet toward either of the magnetic heads 135, 136 as shown by solid lines or broken lines in FIG. Note that the free rotating surface N of the magnetic sheet 131 is the area that the magnetic sheet 131 follows when it rotates without the presence of a magnetic head or control member, and has a thickness of about 100 μm due to waviness and slight vibration of the magnetic sheet.

Further, when the magnetic sheet pack is removed from the magnetic sheet recording/reproducing apparatus of this embodiment and the control bins 142 to 145 are released from the control members 138 to 141, the control members 138 to 141 are elastically magnetically It is displaced away from the sheet 131. As a result, when transporting or storing the magnetic sheet pack, the magnetic sheet 131 and the control member 138
Contact with ~141 is avoided.

In addition to the magnetic heads 135, 136 and the control pins 142 to 145, a magnetic sheet recording and reproducing device that is equipped with such a magnetic sheet pack and records and reproduces data on both sides includes a magnetic sheet 131 as shown in FIG. A spindle motor and its control circuit are used for forward and reverse rotation. That is, a magnetic sheet 1 rotatably stored in a magnetic sheet pack.
Spindle motor 1 equipped with 31 center cores 146
47 is attached with a drive circuit, and this drive circuit is connected to the control circuit 1.
48. The control circuit 148 controls the magnetic heads 135 and 135 in accordance with the rotational direction of the spindle motor 147.
136 is performed. For example, when magnetic recording is performed on the lower surface of the magnetic sheet in FIG. 7 by the magnetic head 136, as shown in FIG. , to the magnetic head 136, and controls the rotation of the spindle motor 147 to rotate it as shown by the solid line arrow in FIG. Along with this rotation, negative pressure is generated between the magnetic sheet 131 and the inclined surfaces 140a and 141a, which move away from the free rotation surface N of the magnetic sheet from the upstream side to the downstream side, and the magnetic sheet 131 is bent, and the magnetic sheet 131 is bent downward in the figure. is attracted to. At the same time, the inclined surfaces 138a, 1 approach the free rotating surface N of the magnetic sheet from the upstream side to the downstream side.
A positive pressure is generated between 39a and the magnetic sheet 131, and the magnetic sheet 131 is bent and pushed downward in the figure. As a result, the outer magnetic sheet 131 is displaced as shown by the solid line in FIG. 7 and comes into sliding contact with the magnetic head 136, thereby performing magnetic recording. Further, when the switches 150 and 152 are switched to the reproduction side, the signal reproduced from the magnetic sheet 131 can be sent to the video reproduction circuit 154.

Further, when magnetic recording is performed on the upper surface of the magnetic sheet in FIG. 7 by the magnetic head 135, the signal from the video recording circuit 149 is set to the recording side with switches 150 and 152 turned on, and switches 155 and 156 are turned on. At the same time, the magnetic head 135 is sent to the magnetic head 135, and the spindle motor 147 is controlled to rotate as shown by the broken line arrow in FIG. Along with this rotation, the inclined surfaces 138g and 139a and the magnetic sheet 1 move away from the free rotation surface N of the magnetic sheet from the upstream side to the downstream side.
A negative pressure is generated between the magnetic sheet 131 and the magnetic sheet 131, and the magnetic sheet 131 is bent and attracted upward in the figure. At the same time, the inclined surface 1 approaches the free rotation surface N of the magnetic sheet as it goes from the upstream side to the downstream side.
Positive pressure is generated between 40a, 141a and the magnetic sheet 131, and the magnetic sheet 131 is bent and pushed upward in the figure. As a result, the magnetic sheet 131 is displaced as shown by the broken line in FIG. 7 and comes into sliding contact with the magnetic head 135, thereby performing magnetic recording. In addition, switch 150. 152 to the reproduction side, the signal reproduced from the magnetic sheet 131 can also be sent to the video reproduction diagram $154.

By reversing the direction of rotation of the magnetic sheet in this manner, it is possible to sequentially contact either magnetic head 135 or 136 to perform recording and reproduction on both sides. Therefore, compared to the case where both magnetic heads 135 and 136 are always in contact with the magnetic sheet 131, wear and damage to the magnetic heads can be prevented. This is especially important for magnetic sheet packs, which have thinner media than 3.5-inch and 5.25-inch floppy disks, have high rotational speeds, and use small-area magnetic heads. Pressure.

Since the magnetic sheet is not in contact with anything other than the magnetic head due to the negative pressure, wear of the magnetic sheet can also be prevented.

Incidentally, the present invention provides control members 138 to 14 as in the above embodiment.
1 is not limited to being supported elastically. For example, as in another embodiment of the present invention shown in FIG.
7b, and this window portion 157a.

Control members 160, 161, 162° 163 may be integrally formed on both circumferential sides of the magnetic heads 158, 159 of 157b. An inclined surface 160m formed at 163 to the control member 160.

The relationship between 161 a, 162 a, 163 a and the free rotating surface N of the magnetic sheet is the same as in the embodiment described above. In such a relationship, as in the embodiment described above, when the magnetic sheet is rotated as shown by the solid arrow in the figure, a positive pressure is generated between the magnetic sheet and the inclined surfaces 160a and 161a, and a positive pressure is generated between the inclined surface 162a and the magnetic sheet. , 163a, the magnetic sheet is bent and displaced as shown by the solid line in the figure, and comes into contact with the magnetic head 159. Conversely, when the magnetic sheet is rotated in the direction of the arrow shown by the broken line in FIG. 10, the magnetic sheet is displaced and comes into contact with the magnetic head 158 as shown by the broken line in the figure.

Furthermore, the control member is not limited to being provided in the protective case, but may be provided in the magnetic sheet recording/reproducing device to which the magnetic sheet pack is attached. For example, as in another embodiment of the present invention shown in FIG. 11, a magnetic head 165.
6 and the window 164 into which the control member 167, 168 is inserted.
m, 164b, and the control members 167, 168 are connected to the window part 1.
64m, 164b into the protective case 164 at the same time as the magnetic head 165, 166, the inclined surface 167a of the control member 167, 168.

The relationship between the magnetic sheet 168a and the free rotation surface N of the magnetic sheet may be the same as in the embodiment described above. With such a configuration, the same effects as those of the above-described embodiment can be achieved.

<Effects of the Invention> As described above in detail based on the examples, the magnetic seat back of the present invention has an inclined surface provided inside the edge of the window of the protective case, and the magnetic seat back rotates between the magnetic seat back and the rotating magnetic sheet. By generating positive or negative pressure, the magnetic sheet is urged or attracted to the magnetic head, resulting in a good head touch. Therefore, since the conventional adjustment plate, control member, etc. are not necessarily required, the recording and reproducing apparatus can be simplified, and the compatibility of the magnetic seat back can be improved.

On the other hand, the magnetic sheet recording and reproducing device of the present invention uses a magnetic sheet that has a relatively thin medium thickness, a small radius, and is rotated at high speed, and recording and reproducing is performed by a magnetic head with a small contact area. However, the positive and negative pressure generated by the rotation of the magnetic sheet is used to bring the magnetic plate into sliding contact with either magnetic head, so just by rotating the magnetic sheet in the forward or reverse direction. It is possible to record and play back both sides.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention, and FIG.
a) is a sectional view showing a modification of the first embodiment; FIG. 2(b) is a sectional view showing a modification of the first embodiment;
) is a view taken along line bb in FIG. 4 and 5 are cross-sectional views of the third embodiment of the present invention, FIG. 6 is an explanatory diagram conceptually showing the structure of the present invention, and FIG. 7 is a cross-sectional view of the third embodiment of the present invention. FIG. 8(a) is a sectional view showing one embodiment (bl is a partial front view of the magnetic sheet pack shown in FIG. 7, FIG. 9 is a configuration diagram showing a control circuit for double-sided recording and reproduction, Fig. 11 is a sectional view showing other embodiments of the present invention, Fig. 12 is a partially cutaway perspective view of the magnetic sheet pack, and Fig. 13 is the X[-Xm line in Fig. 12. Cross section, 1st
Figure 4 (al (b)) is an explanatory diagram of a control member that attracts a magnetic sheet by negative pressure according to the prior art;
The figure is a sectional view of a conventional magnetic sheet recording/reproducing device. In the drawings, 12 is an upper case, 12a and 12b are inclined surfaces, 13 is a lower case, 13a and 13b are inclined surfaces, 15 is a magnetic sheet, 20.21 is a window, 24 is a magnetic head, and 25.26 is a control member. , 131 is a magnetic sheet, 132 is an upper case, 133 is a lower case, 134.157, 164 is a protective case, 127.128
, 135, 136, 158° 159. 165, 166 is a magnetic head, 129. 130, 138, 139, 140
゜141.160, 161, 162, 163゜167.
168 is a control member, 129 m, 130 a, 138 a, 139
a. 140m, 141a, 160a, 161a. 162 a, 163 a, 167 a, 168
m is an inclined surface; 142, 143, 144, and 145 are control bins; 147 is a spindle motor; 148 is a control circuit; 149 is a video recording circuit; 154 is a video playback circuit; N is a free rotation surface. (a) (b) Figure (a) (b) +38 Figure

Claims (2)

[Claims] (1) A flexible disk-shaped magnetic sheet is rotatably stored in a protective case, and windows are opened at corresponding positions in the protective case, and the magnetic head is opened from either of the windows. In a magnetic sheet pack that performs magnetic recording and reproduction by inserting and slidingly contacting the rotating magnetic sheet, the rotating magnetic sheet is placed inside the edge of the other window into which the magnetic head is not inserted. A magnetic sheet pack characterized by forming an inclined surface that biases a head with positive pressure. (2) A flexible disk-shaped magnetic sheet is attached to a spindle motor that can be rotated forward and backward, and first magnetic sheets are placed on both sides of the spindle motor with a slight gap between them.
A second magnetic head is disposed on both circumferential sides of the first magnetic head, and when the magnetic sheets rotate in one direction, negative pressure is generated to attract the magnetic rate to the first magnetic head. and a control member having an inclined surface that generates positive pressure when the magnetic sheet rotates in the other direction to push the magnetic sheet toward the second magnetic head. .