JP2002042437A - Tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tape cassette which can prevent the flawing of a magnetic tape while smoothly sliding a tape winding body. SOLUTION: This tape cassette has a cassette case which has an upper case and a lower case, the tape winding body which is wound with a magnetic tape on a pair of hubs and an upper sheet and lower sheet 5a which are formed with a pair of holes for insertion respectively insertable with a pair of drive shafts on the right and left and are respectively arranged above and below the magnetic tape. Thick wall parts 25a to 25d for blocking the contact of the outer peripheral wall of the cassette case and the magnetic tape are erected in a part at the outer edge of at least either of the upper sheet and the lower sheet 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette in which sheets are provided between an inner surface of a cassette case and a magnetic tape.

[0002]

2. Description of the Related Art As a tape cassette of this type, there is a tape cassette disclosed in Japanese Utility Model Laid-Open No. 2-12782. The tape cassette includes a magnetic tape (3) wound around a hub (2, 2), a cassette case for accommodating the hub (2, 2) and the magnetic tape (3), and a magnetic tape (3). A lubricating sheet (1, 1) housed in a cassette case to smoothly slide the magnetic tape (3). In this case, the slip sheet (1, 1) has a drive shaft insertion hole (1A, 1A, 1) through which a drive shaft (a shaft for rotating a tape wound body) of a reproducing device that engages with the hub (2, 2) can be inserted. 1A, a shaft insertion hole). Further, the lubricating sheet (1, 1) has a convex portion (1B, 1B, 1B) for reducing the area in contact with the magnetic tape (3) to reduce the frictional force with the magnetic tape (3).
1B) is formed. This convex part (1B, 1B)
Are peripheral convex portions (1C, 1C) formed around the drive shaft insertion holes (1A, 1A) and peripheral convex portions (1C, 1C).
Four radially convex portions (1D, 1D.) Formed radially from C) to positions beyond the maximum winding diameter of the magnetic tape (3).
・).

[0003]

However, this tape cassette has the following problems. That is, in recent years,
For example, in a tape cassette used as a backup medium, it is necessary to increase the recording capacity as the amount of data to be backed up increases. For this reason, in today's large-capacity tape cassettes, the recording capacity is increased by forming the magnetic tape itself thin and increasing the maximum winding diameter. Therefore, since the magnetic tape in the tape cassette having a large recording capacity is formed to be thin, even if the magnetic tape slightly contacts the left and right side walls and the rear wall of the cassette case and the outer edge of the slippery sheet (1, 1). It may be damaged. On the other hand, in the case of a tape cassette with a large recording capacity, it is necessary to maintain compatibility in terms of shape with the existing tape cassette.When the maximum winding diameter of the magnetic tape is increased, the outermost peripheral portion of the magnetic tape is Get close to the outer wall. Generally, in this type of tape cassette, the hub is held in a cassette case so as to be able to move slightly forward, backward, left and right in order to rotate the hub smoothly. Therefore, the magnetic tape wound around the hub to the maximum diameter moves together with the hub in the cassette case back and forth, right and left, and the magnetic tape at the outermost periphery may come into contact with each side wall of the cassette case and be damaged. The problem exists.

Further, in this type of tape cassette, a hub brake for preventing rotation of the hub in a state where the magnetic tape is taken out of the recording / reproducing apparatus is provided in the cassette case, so that the magnetic tape in the cassette case can be used. There is also a type configured to prevent loosening. In this type of tape cassette, the hub brake is biased by a spring toward the rear wall of the cassette case, and the hub brake brake pawl is engaged with a gear formed on the peripheral surface of the hub to engage the hub brake. Rotation is blocked. Accordingly, the magnetic tape is moved toward the rear wall of the cassette case together with the hub by the urging force. As a result, the outermost magnetic tape (3) easily comes into contact with the rear wall of the cassette case. However, there is also a problem that it may be damaged.

In a tape cassette having a large recording capacity,
Since it is necessary to store various other components in the tape cassette, the shape of the sheet must be complicated. However, when the shape of the sheet is complicated, of the corners in the sheet surface, the corners protruding in the direction outside the sheet surface are easily turned up and easily come into contact with the magnetic tape. Therefore, the radial convex portions (1D, 1D...) Are formed on the peripheral convex portions (1C, 1C).
The conventional tape cassette in which the tapes are simply connected to each other has a problem in that the corners of the slippery sheet (1, 1) protruding out of the sheet surface come into contact with and damage the tape edge of the magnetic tape (3). Not only is there a point, but in the worst case, the lubricating sheet (1, 1) in contact with the tape edge is entangled in the tape wrapping body and the wrapped lubricating sheet (1, 1) wraps the tape. There is a very serious problem in that the rotation of the body is hindered and the magnetic tape (3) is cut off.

Further, in the conventional tape cassette, the two convex portions (1B, 1B) are formed separately or independently, or are merely connected to each other by a narrow convex portion. ing. Therefore, since the slippery sheet (1, 1) has a structure which is easily bent in the longitudinal direction (left-right direction), the left and right outer edges of the slippery sheet (1, 1) are tape edges of the magnetic tape (3). Makes it easier to contact.
For this reason, there is also a problem that the tape edge of the magnetic tape (3) is more easily damaged. On the other hand, 6-770
No. 76 discloses a technique in which a convex portion is formed between the left and right outer edges of a sliding sheet (slippery sheet) to reduce the deflection itself. However, this technique has a problem that the outer edge of the convex portion formed up to the end of the sliding sheet is always in contact with the magnetic tape, so that the tape edge is surely damaged.

[0007] The present invention has been made in view of such a problem, and while smoothly sliding a tape wound body,
A main object of the present invention is to provide a tape cassette capable of preventing a magnetic tape from being damaged. Another object of the present invention is to provide a tape cassette capable of preventing sheet entanglement.

[0008]

In order to achieve the above object, a tape cassette according to the present invention comprises a cassette case having an upper case and a lower case, and a tape winding body having a pair of hubs around which a magnetic tape is wound. A tape cassette comprising an upper sheet and a lower sheet, wherein a pair of insertion holes into which a pair of drive shafts can be inserted are formed on the left and right, and which are disposed above and below the magnetic tape, respectively. A thin wall portion for preventing contact between the outer peripheral wall of the cassette case and the magnetic tape is provided upright at a part of the outer edge of at least one of the lower sheets.

In this case, it is preferable that the wall portion is provided upright on the outer edge portion near the side wall and the rear wall of the cassette case. Further, it is more preferable to form the wall portion by bending the outer edge portion of the at least one sheet, and when such a configuration is adopted,
Production of the sheet becomes easy.

[0010] Further, a convex portion protruding toward the tape winding body and capable of elastically contacting the tape edge of the magnetic tape is formed on each of the two sheets, and the convex portion is at least a left end portion of the sheet. It includes the insertion hole from the vicinity to the vicinity of the right end, and has a rectangular area wider than the diameter of the insertion hole and protrudes in a direction outside the sheet surface among the corners in the sheet surface. It is preferable that the region is formed from the vicinity of the corner to the region communicating with the rectangular region.

Further, the two sheets are preferably formed symmetrically with respect to each other. If such a configuration is adopted, the sheets can be manufactured at low cost.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a tape cassette according to the present invention will be described below with reference to the accompanying drawings.

First, the configuration of the tape cassette 1 will be described with reference to the drawings.

The tape cassette 1 is a magnetic tape cassette (DDS) used as a backup medium for backing up various data recorded in a recording device in a computer, for example, as shown in FIG.
A cassette case 2, a tape winding body T around which a magnetic tape 4 is wound, sheet members 5a and 5b, a hub brake 6, a slider 7, and a semiconductor memory substrate M are provided. In this case, the semiconductor memory substrate M includes a substrate 31, a semiconductor memory 32 mounted on one surface of the substrate 31, and an antenna 33 formed on the other surface of the substrate 31, and has a total thickness of 1.3 mm. It is formed in a thin plate shape. The semiconductor memory substrate M is fixed at a predetermined position in the cassette case 2, and various data such as recorded information of recorded data and type information of a tape cassette are read and written by a recording / reproducing device (not shown) in a non-contact manner. .

The cassette case 2 includes, as shown in FIG.
Upper case 11 and lower case 1 that can be fitted together
2, a tape-wrapped body T, a sheet member 5
a, 5b, the hub brake 6, and the like. As shown in FIG. 2, a rectangular window hole 11 a is formed in the upper case 11, and the winding amount of the magnetic tape 4 in the tape wrapping body T can be reduced through the window hole 11 a. It can be seen from the outside. As shown in FIG. 1, a window member 15 formed of a transparent resin into a flat plate shape is fitted into the window hole 11a from the inside. The window member 15 is formed with a guide piece (not shown) for holding the hubs 3 and 3 rotatably in cooperation with the lower case 12. Further, when the tape cassette 1 is removed from a recording / reproducing apparatus (not shown), the magnetic tape 4 pulled out to the front of the cassette case 2 is provided in the upper case 11.
A cover member 16 for covering and protecting the recording surface is rotatably attached. In this case, the lid member 16 is urged toward a closing position that covers the magnetic tape 4 by a spring S1 disposed between the lid member 16 and the upper case 11. FIG.
As shown in the figure, a rib 11 is provided at the center of the rear wall 11b of the upper case 11 to press the semiconductor memory substrate M against the lower case 12 by contacting the upper end of the semiconductor memory substrate M.
c, 11c, 11c are formed. Furthermore, back wall 1
1b and the front wall 11d, in order to be able to store the tape winding body T having the maximum winding diameter increased by winding the longer magnetic tape 4 in the radial direction of the tape winding body T. Are formed in the shape of a circular arc.

As shown in FIG. 3, the lower case 12 is formed with shaft insertion holes 12a, 12a for inserting a shaft for rotating a tape winding body in the recording / reproducing apparatus, and the shaft insertion holes 12a, 12a. Are formed around the periphery of the housing 3 for holding the hubs 3 and 3 rotatably. In the vicinity of the center of the rear wall 12b on the bottom surface of the lower case 12, the upper surface of the rear wall 1b serves as holding means for holding the semiconductor memory substrate M together with the rear wall 12b.
A pair of holding members 12c, 12c each having an L-shape in sectional view formed at a height protruding above the upper surface of the semiconductor memory substrate 2b; and a columnar member 12d for limiting the bending of the semiconductor memory substrate M in a mounted state to a predetermined amount or less. Is erected. In this case, the holding members 12c function as a positioning member for positioning the semiconductor memory substrate M in the front-rear direction and a positioning member for positioning in the left-right direction. The columnar member 12d is
It stands upright at a position corresponding to the thickness of the semiconductor memory substrate M with respect to the rear wall 12b. Also, back wall 1
2b has a concave portion 1 having a concave inner wall surface in order to prevent the antenna 33 of the semiconductor memory substrate M from being damaged.
2e is formed. Further, the rear wall 12b and the front wall 12
f and the left and right side walls 12g, 12g are formed with concave portions 12h, 12h, etc., which are recessed in an arc shape with respect to the radial direction of the tape winding body T so that the tape winding body T can be stored. ing. Further, a part of the inner surface of the front wall 12f of the lower case 12 is formed in an arc shape so as to be able to face the outermost magnetic tape 4 in the tape winding body T having the largest winding diameter with a small separation distance. .

As shown in FIG. 1, the tape wrapping body T includes a hub 3, 3 and a magnetic tape 4 wound around the hub 3, 3.
And is housed in the cassette case 2 while being sandwiched by the sheet members 5a and 5b. in this case,
The magnetic tape 4 has a thickness of, for example, about 9 μm to 5 μm and a length of about 90 m to 170 m according to the storage capacity. The hubs 3 and 3 are held by the window member 15 and the lower case 12 so as to be slightly movable in the front, rear, left and right directions in the cassette case 2 in order to smoothly rotate the tape winding body T. Sheet members 5a, 5b
Correspond to the lower sheet and the upper sheet in the present invention, respectively, and smoothly slide the tape winding body T while preventing the magnetic tape 4 from being damaged. Further, the sheet members 5a,
5b is formed of ultra-high molecular weight polyethylene having a thickness of about 30 to 50 μm or polyethylene terephthalate (PET) provided with a silicon layer for reducing contact resistance on the contact surface side with the tape winding body T. . The sheet members 5a and 5b are formed transparent so that the amount of the magnetic tape 4 wound up through the window member 15 can be visually checked. In this case, the sheet members 5a and 5b are formed symmetrically with each other by embossing in a thickness direction with a mold having a predetermined shape.

Specifically, as shown in FIG. 4, the sheet member 5a has a hub insertion hole into which the hubs 3 and 3 of the tape winding body T and the tape winding shaft of the recording / reproducing apparatus can be inserted. 21 and 21 are convex portions 22 which elastically contact with the magnetic tape 4 while reducing the contact resistance to the magnetic tape 4 to prevent winding disturbance.
And walls 25a to 25d for preventing contact between the magnetic tape 4 and the inner wall of the cassette case 2. The protrusion 22 is formed around the hub insertion holes 21 and 21 by, for example, 0.2 mm.
It is formed so as to protrude convexly at a height of about mm. Also, as shown in FIG.
a is a region extending from the vicinity of the left end portion to the vicinity of the right end portion of a, and includes the hub insertion hole 21 and is formed in a rectangular region wider and wider than the diameter of the hub insertion hole 21.
And a projection 24 extending from the vicinity of a corner of the sheet member 5a protruding in a direction outside the sheet surface among the respective corners in the sheet surface.
23a respectively formed in the region communicating with the region
To 23h. In this case, FIG.
As shown in the figure, the projections 23c to 23h and the ends 24a and 24b of the projection 24 are within the region of the maximum winding diameter of the tape winding body T and do not reach the outer edge of the sheet member 5a. Formed in the area. Further, the convex portions 23a and 23b are formed in regions where a part thereof is outside the region of the maximum winding diameter of the tape winding body T and does not reach the outer edge of the sheet member 5a.

On the other hand, the wall portions 25a to 25d are, as shown in FIG.
2b and the left and right side walls 12g are formed by bending a part of the vicinity of the side walls 12g. In addition, wall part 2
5a to 25d are formed at a height slightly lower than the rear wall 12b of the lower case 12, and are bent substantially at right angles to the sheet surface of the sheet member 5a. The wall 25
When the bending angle of a to 25d is slightly smaller than the right angle, the mounting operation of the tape winding body T at the time of assembling the tape cassette 1 becomes easy.

As shown in FIG. 1, the hub brake 6 includes brake claws 6a, 6a and arm portions 6b, 6b, and the direction in which the brake claws 6a, 6a engage with gears formed on the hubs 3, 3. Urged by a spring S3.
Therefore, in this state, since the rotation of the hubs 3 is prevented, the magnetic tape 4 in the cassette case 2 is prevented from loosening. On the other hand, when the arm portions 6b, 6b are pulled forward with the rotation of the lid member 16, the engagement of the brake claws 6a, 6a with the hubs 3, 3 is released. Rotation is allowed. The slider 7 is formed in a U-shape as a whole, and is slidably fitted to the lower case 12. The slider 7 is provided with a shaft insertion hole 12 of the lower case 12 while preventing rotation of the lid member 16.
a and 12a are urged by a spring S2 toward the position to close. Further, when the tape cassette 1 is loaded in the recording apparatus, the slider 7 engages with a predetermined portion in the recording apparatus and slides with respect to the lower case 12, thereby allowing the rotation of the lid member 16. I do. At this time, the shaft insertion holes 7a, 7a of the slider 7 and the shaft insertion holes 12a, 12a of the lower case 12 communicate with each other in the up-down direction, and the shaft for rotating the tape winding body can be inserted. On the other hand, when the tape cassette 1 is ejected from the recording apparatus, the tape cassette 1 moves to the open position of the
, And the shaft insertion holes 12a, 12a of the lower case 12 are closed to prevent dust from entering.

In the tape cassette 1, as shown in FIG. 6, the tape edge of the magnetic tape 4 is
The projections 23a to 23h and the projections 24 of the a and 5b are in contact with each other. In this case, the respective protrusions 22 of the sheet members 5a and 5b are brought into elastic contact with the magnetic tape 4 so that FIG.
As shown in, for example, in the vicinity of the convex portions 23h, 23h,
The outer edges 26 of the sheet members 5a, 5b are separated from the magnetic tape 4, respectively. Therefore, each outer edge 2
6, 26 and the magnetic tape 4 can be prevented from being in contact with each other.
6, 26 can be prevented from being wound around the tape winding body T. Further, each of the convex portions 23a to 23h is
Since each of the corners a and 5b is formed toward a corner protruding in a direction outside the sheet surface, the sheet members 5a and 5b at each corner are reliably prevented from being turned up. Further, by forming the rectangular projections 24 on the sheet members 5a and 5b, the sheet members 5a and 5b
As a result, it is possible to prevent the outer peripheral portion in the left-right direction and the magnetic tape 4 from contacting each other.

Further, in the tape cassette 1, the hubs 3, 3 are urged rearward by the hub brake 6. Therefore, since the tape winding body T is moved toward the rear walls 11b and 12b of the upper case 11 and the lower case 12, the outermost magnetic tape 4 is moved to the rear walls 11b and 12b.
It approaches to the very vicinity of 12b. In this case, as shown in FIG. 9, the wall portions 25b, 25b of the sheet members 5a, 5b
(Or 25a, 25a) is located between the rear walls 11b, 12b and the magnetic tape 4, so that the magnetic tape 4 moved to the rear walls 11b, 12b side hits the walls 25b, 25b (or 25a, 25a). Touch Therefore, direct contact between the magnetic tape 4 and the rear walls 11b, 12b can be prevented, so that damage to the magnetic tape 4 can be avoided, thereby improving the reliability of the tape cassette 1. . Further, the tape winding body T abutting against the walls 25b, 25b is moved by the repulsive force of the walls 25b, 25b.
Since the hubs 3 and 3 are pushed back to the side of 1d and 12f, the hub brake 6 can be more reliably engaged.
In addition, the repulsive force pushes the central portion of the tape winding T back toward the central portion of the shaft insertion hole 12a, so that the tape winding rotating shaft of the recording / reproducing apparatus is smoothly moved to the hubs 3, 3. It can also be inserted.

On the other hand, when mounted on a recording / reproducing apparatus, FIG.
As shown in (1), the magnetic tape 4a pulled out from the tape winding body T and the magnetic tape 4b to be wound pass while the tape edges are in contact with the convex portions 23b, 23a. For this reason, the magnetic tapes 4a and 4b can be positioned at predetermined positions in the height direction. Therefore, it is possible to prevent the magnetic tapes 4a and 4b from being damaged or disturbed due to the contact with the cassette case 2. When the magnetic tape 4 is wound by a predetermined amount from the sending-side hub 3 to the winding-side hub 3, as shown in FIG. 8, contact between the outermost peripheral magnetic tape 4 and the outer edge 26 is reduced. Since it is avoided, damage due to contact with the outer edge portion 26 can also be prevented.

When an external force is applied to the tape cassette 1 and the tape cassette 1 vibrates in a state where the tape cassette 1 is detached from the recording / reproducing apparatus, the tape winding body T may move in the cassette case 2 in the left-right direction. In such a case, even if the magnetic tape 4 is wound around any one of the hubs 3 and 3, any one of the walls 25a to 25d is connected to the side walls 12g, 12g of the cassette case 2 and the magnetic tape 4. Prevents contact with Therefore, both side walls 12 of the cassette case 2
g, 12g can be prevented from being damaged. As described above, in the tape cassette 1, it is possible to prevent the magnetic tape 4 from being damaged even if the tape winding body T moves in any direction.

It should be noted that the present invention is not limited to the above-described embodiment of the invention, but can be appropriately modified. For example, the number of formed wall portions and the formation position in the present invention are determined by the tape cassette 1.
However, the present invention is not limited to the configuration example, and may be formed at a part of the outer edge portion between the front wall 12f of the cassette case 2 and the tape winding body T in the sheet members 5a and 5b. On the other hand, in the sheet members 5 a and 5 b of the tape cassette 1, a wall portion is unnecessary for a portion where the magnetic tape 4 and the cassette case 2 are not likely to come into contact with each other or a portion where the magnetic tape 4 is not damaged even if it comes into contact. Manufacture of the sheet members 5a and 5b becomes easy. Further, in the embodiment of the present invention, the example in which the wall portions are formed by bending the outer edges of the sheet members 5a and 5b has been described.
A thin separate member may be provided upright on the outer edge portion. Further, in the embodiment of the present invention, the example in which the wall portions 25a to 25d are formed on both the sheet members 5a and 5b has been described.
For example, the walls 25a to 25d are formed on only one of the sheet members 5a and 5b, or the walls 25a and 25b are formed on the sheet member 5a, and the wall 25 is formed on the sheet member 5b.
The locations where the wall portions are formed can be changed as appropriate, for example, by forming c and 25d.

Further, in the embodiment of the present invention, the projections 23a to 23a are connected to the areas communicating with the outer periphery of the hub insertion hole 21 from the vicinity of the outwardly protruding corners of the sheet members 5a and 5b.
Although the example in which 23h is formed has been described, the present invention is not limited to this. In addition to the protrusions 23a to 23h, a portion where the sheet members 5a and 5b are easily bent (that is, the outer edge portion contacts the magnetic tape 4). A protruding portion reaching the vicinity of the (easy portion) can be appropriately added. In the embodiment of the present invention, the magnetic tape 4 pulled out from the tape winding body T is used.
a, and the magnetic tape 4 wound around the tape winding body T
The example in which the protrusions 23a and 23b are formed so as to be able to abut on the protrusion 23b is described, but the present invention is not limited to this.
The protrusions a and 23b may be formed to have the same length as the protrusions 23c to 23h, and the protrusions that can contact the magnetic tapes 4a and 4b may be formed separately from the protrusions 22.

Further, in the embodiment of the present invention, an example has been described in which the semiconductor memory substrate M on which data is read and written in a non-contact manner by the recording / reproducing apparatus is provided in the cassette case 2, but the present invention is not limited to this. However, this type of tape cassette does not have a semiconductor memory substrate, and a tape that has a semiconductor memory substrate that has data input / output electrodes and that can read and write data while electrically connected to a recording / reproducing device. The present invention can be suitably applied to a cassette. Further, the tape cassette in the present invention is not limited to the DDS shown in the embodiment of the present invention, and the present invention can be suitably applied to various tape cassettes including various video tapes such as DVC and audio tapes. .

[0028]

As described above, according to the tape cassette of the present invention, at least a part of the outer edge of at least one of the upper sheet and the lower sheet prevents contact between the outer peripheral wall of the cassette case and the magnetic tape. Since the thin wall portion is erected, direct contact between the magnetic tape and the outer peripheral wall of the cassette case can be avoided even if the tape winding body moves within the cassette case. It is possible to prevent the magnetic tape from being damaged while smoothly sliding the body.

According to the tape cassette of the present invention, the wall is erected on the outer edge near the side wall and the rear wall of the cassette case, so that the wall is erected on the entire outer peripheral wall. Compared to the configuration, while effectively avoiding damage to the magnetic tape by the outer peripheral wall that is likely to contact,
An increase in sheet manufacturing cost can be suppressed.

Further, since the wall portion is formed by bending the outer edge portion of the sheet, the sheet including the wall portion can be manufactured at low cost.

According to the tape cassette of the third aspect, since the convex portions are formed on both sheets, the tape winding body is smoothly slid, and the corner portions of both sheets are turned up by the convex portions. Can be avoided. Therefore, it is possible to avoid contact between the corner and the magnetic tape, thereby reliably preventing the magnetic tape from being damaged and the corner of the lower sheet from being wound into the tape winding body.

Further, according to the tape cassette of the fifth aspect, since both sheets are formed symmetrically with respect to each other, the tape cassette can be manufactured using one type of mold, so that both sheets can be manufactured at low cost. .

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a tape cassette 1 according to an embodiment of the present invention.

FIG. 2 is a plan view of an upper case 11 of the cassette case 2 in the tape cassette 1 as viewed from inside.

FIG. 3 is a plan view of the lower case 12 of the cassette case 2 in the tape cassette 1 as viewed from the inside.

FIG. 4 is an external perspective view of a sheet member 5a.

FIG. 5 is a plan view of the sheet members 5a and 5b.

FIG. 6 is a transparent view showing an arrangement of a cassette case 2, a tape winding body T, and sheet members 5a and 5b.

FIG. 7 shows outer edge portions 26, 2 of sheet members 5a, 5b.
6 is a side view showing the vicinity of FIG.

FIG. 8 is an outer edge portion 26, 2 of the sheet member 5a, 5b.
6 is another side view showing the vicinity of FIG.

FIG. 9 shows wall portions 25b, 2 of sheet members 5a, 5b.
5b, and rear walls 11b,
It is a side view which shows the vicinity of 12b.

[Explanation of symbols]

 Reference Signs List 1 tape cassette 2 cassette case 3 hub 4, 4a, 4b magnetic tape 5a, 5b sheet member 11 upper case 11b rear wall 11d front wall 12 lower case 12b rear wall 12g side wall 12f front wall 21 hub insertion hole 22 convex portion 23a to 23h Projection 24 Projection 24a, 24b End 25a-25d Wall 26 Outer edge T Tape wrapping

Claims (5)

[Claims] 1. A cassette case having an upper case and a lower case, a tape winding body in which a magnetic tape is wound around a pair of hubs, and a pair of insertion holes into which a pair of drive shafts can be inserted, respectively. A tape cassette comprising an upper sheet and a lower sheet formed and arranged respectively above and below the magnetic tape, wherein a part of an outer edge portion of at least one of the upper sheet and the lower sheet includes a cassette case. A tape cassette, wherein a thin wall portion for preventing contact between an outer peripheral wall and the magnetic tape is provided upright. 2. The tape cassette according to claim 1, wherein said wall portion stands upright on said outer edge portion adjacent to a side wall and a rear wall of said cassette case. 3. The tape cassette according to claim 1, wherein the wall is formed by bending the outer edge of the at least one sheet. 4. The two sheets are each formed with a convex portion projecting toward the tape winding body and capable of elastically contacting a tape edge of the magnetic tape, and the convex portion is formed at least in the sheet. From the vicinity of the left end to the vicinity of the right end, the hole includes the insertion hole, and is wider than the diameter of the insertion hole and has a rectangular area. The tape cassette according to any one of claims 1 to 3, wherein the tape cassette is formed from a vicinity of the protruding corner to a region communicating with the rectangular region. 5. The tape cassette according to claim 1, wherein the two sheets are formed symmetrically with respect to each other.