JPS6163977A - Tape cassette - Google Patents

Abstract

PURPOSE:To position a cassette with high accuracy even though distortions, etc. are produced in a molding mode, by securing the prescribed conditions between a reference hole of a cassette main body and a reference shaft at the device side to set both the reference hole and and the reference shaft to each other. CONSTITUTION:When a cassette main body is positioned, the cassette is pressed to a reference shaft 20 at the device side or a shaft 30. For instance, the rear sides of a pair of shafts 30 have no contact with a contact face 36a' of a lower half 3 and so with the right side when the back-forth positioning is carried out by means of a pair of shafts 20. For the right and left direction, the width alpha'of a left reference hole 16 is sset smaller than that of a right reference hole. Therefore, the degree of freedom is restricted so that only the left contact faces 16c' and 16b' touch the shafts 20. This secures the cassette positioning with high accuracy despite some distortions, etc. produced in a molding mode.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an improved double-sided audio tape cassette with a lid, which is simple and inexpensive to construct.

Conventional Structure and Problems In recent years, magnetic recording using tape cassettes has become more sophisticated and denser, and it has become necessary to prevent dirt, dust, fingerprints, etc. from getting on the tape. Tape cassettes with lids have already been used as video tape cassettes, but these are mainly used on one side. The audio tape cassette used for both A and B cannot be used up to the first type, and a compact and simple structure tape cassette with a lid is in demand. In addition, the lid does not open inadvertently during use, and when inserted into a shallow type, the automatic opening and closing mechanism is simple and stable. There is a demand for something that can be implemented at a low cost and that satisfies conditions such as something that does not cause discomfort even when the product is used.

The tape cassettes proposed by the present inventors so far will be described below. Figure 1 is a perspective view showing the closed state of the tape cassette proposed in Japanese Patent Application No. 69-12339, where 1 is the cassette body, 2 is the upper half of the cassette, 3 is the lower cassette), and 4 is U-shaped. The lid body, 5 is a U-shaped side part of the lid body, 16 is a so-called reference hole for cassette positioning, and is a hole into which a member for positioning a cassette that has been moved to a predetermined playing position is inserted. The rear end of the side 5 of the shape difference body 4 projects into this hole. A protection plate 17 extends from the side surface of the cassette body 1 so as to cover the U-shaped side portion 5 of the cassette body.

FIG. 2 is a perspective view showing the open state of the lid, in which 9° 1Q is a partition bar forming an opening on the front surface of the cassette body; 11.
12. 13 is an opening, 15 is a tape, and 18 is a protruding edge provided at the upper and lower edges of the cassette opening, between which the U-shaped lid 4 is fitted to prevent rotation of the U-shaped lid 4. do. 19
is a protrusion and a concave portion formed by the ink 18.

FIG. 3 is a partial top view showing the inside of the U-shaped lid 4, where 6 is a pivot shaft of the U-shaped lid 4, and 7 is a leaf spring that is integrally formed with the pivot shaft 6. It is attached to the rear of the cassette. Reference numeral 8 denotes a fitting hole for the rotation support shaft 6, which is formed on the side surface of the cassette body 1 in a substantially triangular shape that tapers toward the rear. It guides and positions the shaft 6.

Fig. 4 is a sectional view of the main part showing the engagement relationship of the U-shaped lid 4, and Fig. 5 is a full view of the main part showing the correspondence relationship between the device and II because it opens automatically. A cassette positioning reference shaft provided on the side corresponds to the cassette positioning reference hole 16. 21 is a contact member for opening the U-shaped lid body 4;
It is installed on the equipment side.

The operation of the tape cassette constructed as described above will be explained below. First, in order to open the lid of the tape cassette in the closed state shown in Figure 1, it is necessary to pull the U-shaped lid 4 away from the opening surface and release the locking relationship that prevents rotation as shown in Figure 4. be. However, since the protective plate 1 covers the side part 5 of the U-shaped lid 4, the U-shaped lid 4 cannot be easily pulled out, and this becomes possible only after the device is completely damaged.

Now, as the cassette in the closed state is moved in the direction of arrow A as shown in FIG. The rear end of the side portion 5 of the U-shaped lid body is pushed forward by the positioning reference shaft 20, and the U-shaped lid body 4 is
It moves in the direction of arrow B shown in the figure, and the locking relationship between the U-shaped lid 4 and the four parts 19 on the opening surface of the cassette main body is released.

After this, as the cassette continues to move in the direction of arrow A,
The abutment member 21 abuts the lower end of the U-shaped lid 4, pushes up the U-shaped lid 4 in the direction of arrow C, and rotates it.

When the U-shaped lid 4 rotates more than about 45 degrees, it automatically rotates by the force of the barb 70, and is self-maintained in the open position where it can be rotated 90 degrees. Further, these operations are performed in exactly the same way in both A and B.

However, the tape cassette configured as above,
The cassette rear wall surface of the positioning reference hole 16 is pressed along the positioning reference shaft 2Q implanted in the device I11, and the predetermined position of the cassette body 1 is determined.
There are variations in the flatness accuracy of the cassette rear side wall surface of the reference hole 16 consisting of the lower...-), and the difference between the reference axis 2o and the reference hole 1
6. Gap between the cassette body and the cassette body due to horizontal play, etc.
There were some difficulties in ensuring the accuracy of positioning the cassette body 1 at a predetermined position. In particular, tape cassettes for P, C, and U system magnetic recording and reproducing systems, which perform narrow track, short wavelength magnetic recording and reproducing, have a higher relative positional accuracy between the magnetic tape and the magnetic head than conventional analog system so-called compact cassettes. Coupled with the fact that it is required to be much higher than the previous one, further improvement was needed in terms of the positioning reproducibility of the cathode body 1.

OBJECTS OF THE INVENTION The present invention improves the above tape cassette,
The objective is to provide a tape cassette with excellent positioning reproducibility with respect to the reference axis implanted from the f-shallow mold side, which is convenient both in terms of mold construction and mass production.

Structure of the Invention The present invention comprises a cassette body having an opening at one end, and at least a pair of substantially square reference holes for positioning the cassette body, which are located within the cassette body. The rear side wall surface is brought into contact with at least one pair of reference shafts installed on the device side to determine its longitudinal position, and the lateral dimension of the cassette body of only one of the pair of reference holes is determined. By making the other reference hole smaller than the lateral dimension of the cassette body, the gap between the other reference hole and the reference shaft installed from the equipment side is reduced, and the reference hole determines the lateral position of the cassette body. By configuring the reference hole to be limited to the section where the reference shaft can come into contact with the inner wall surface of the reference hole, the contact wall surface within the reference hole is limited only to the vicinity of the upper and lower surfaces in the thickness direction of the cassette body. A tape cassette with a simple configuration and low cost that is easy to purchase molds and mass-produce, and that provides high precision and repeatable positioning of the cassette body with respect to the reference axis installed on the equipment side. It is.

DESCRIPTION OF THE EMBODIMENT FIGS. 6(a) and 6(b) are plan views showing details of the vicinity of the reference hole on the lower half of the tape cassette according to an embodiment of the present invention, and FIG. 6(a) is the left side of the tape cassette. Please provide a detailed diagram of the vicinity of the standard. In Figure 6 (-), 3 is below...-
5 is a U-shaped lid side part, 15 is a magnetic tape, 16 is a left reference hole, and 17 is a protection extending from the side of the cassette lower nozzle 3 so as to cover the U-shaped lid side part 5. It is a plate whose width is the same as the U-shaped lid side part 5, and the lower half 3
This is provided only on the left side III 9f11.

Reference numeral 36 is a hole provided at a position to sandwich the magnetic tape 15 with respect to the reference hole 16, into which the shaft 30 with the optical detection device inserted penetrates. Determine the end. 21 and 2 degrees are recesses provided in the upper half -72 and the lower half 3 to allow light to pass through, and by combining the upper and lower halves, the base r.
, (forms a circular or rectangular hole that optically connects the hole 16 and the hole 36 when the magnetic tape 15 is transparent. Bunjin 3
6 sometimes uses a vehicle 30 incorporating a photodetector Ft,
The reflection of light on the magnetic tape 15 is also utilized in a structure for determining the beginning and end of the tape, in which case only the recess 22 is used.

Figure 6(b) is a detailed view of the vicinity of the right standard scale, and 3 is the bottom...
-F, 5 is a U-shaped lid (ll1 part, 15 is a magnetic tape,
116 is a reference hole on the right side, 17 is a protection plate extending from upper)--F 2, and when the upper and lower...-F are combined, the 6th
Although it is located at the location shown in FIG. 3B, it is not formed near the right reference hole 116 on the lower half 3. 126 is the 6th
This hole has the same function as the hole 36 shown in FIG. 11. β2 is also a concave portion formed for the same purpose as in FIG. 6(,).

In FIGS. 6(a) and 6(b), a pair of reference shafts 20,
Alternatively, the left and right shafts 30 are formed to have the same outermost diameter, and the position of the cassette body 1 in the front and back direction is determined by pressing the cassette body 1 against the rear of a pair of left and right standards 1 (I120 or shafts 3o). An explanation will be added regarding the case where the cassette main body 1 is positioned using the base/Hayabusa shaft 20. In this case, the left and right pair of 4M+ 30 are as shown in Fig. 6(a).
, Φ) is formed slightly smaller than the outer diameter shown in the reference shaft 20.
The rear side is the contact surface 16a' of the lower half 3.

116a' to determine the longitudinal position of the lower half 3, the rear of the pair of shafts 30 is the contact surface 36 of the lower half 3
It is configured so as not to come into contact with a', 126j. Also, the left-hand reference hole 1 is used to position the cassette body 1 in the left-right direction.
6, and the width a' of the left (1t+1) reference hole 160 is formed approximately equal to the reference axis 20, thereby positioning the cassette body 1 in the left-right direction.On the other hand, the width β1 of the cloth full reference hole 116 is α1<β1. Therefore, with respect to the left and right reference shafts 2o of -χ·1 having the same outer diameter, the lower cassette -73 is the abutment wall surface 16d of the left reference hole 16 in the left and right direction of the cassette.

The cassette body 1 contacts the reference shaft 2o only at the point 16d.
This will restrict the degree of freedom in the left and right direction.

Although the case where the cassette main body 1 is positioned using the left and right pair of reference shafts 2o has been described above, the same can be said about the case where the cassette rear 1 is positioned using the left and right pair of shafts 30.

In this case, the outermost diameter of the pair of left and right reference shafts 20 is -
), it is natural that it is formed slightly smaller than that shown in (b). In other words, the rear of the pair of shafts 3o is the cassette 1.
When abutting against the abutting wall surfaces 36a', 126a' of the lower half 3 and determining its position in the front-rear direction, the rear side of the pair of left and right reference shafts 20 is the abutting wall surface 16a' of the lower half 3.

116a'. Also, the left reference hole 16
The width α of the left hole 36 is in the relationship α1=α2, and the width β1 of the right reference hole 1160 and the width β1 of the right hole 1
The width β of 26 is formed in the relationship β1=β2.

As a result, with respect to the pair of left and right shafts 3o having the same outer diameter, the lower half 3 contacts the shaft 3o only at the contact wall surfaces 36b' and 36C' of the left hole 36 in the left and right direction of the cassette (& in the left and right direction of the cassette main body 1). It has a configuration that restricts the degree of freedom.

In the tape cassette according to this embodiment, the protection plate 17, the reference holes 16, 116, and the holes 36, 126 are formed in the lower half 3 and the upper half 2 in exactly the same shape.
, bottom) - Reference hole 16° 116, including hole 3, hole 36.1
The 26 cassette transverse cross-sections and ten-direction cross-sections are, respectively,
Figure 6), left and right reference holes 16, 1 shown in (b)
16, and in hole 35.126 (a).

(b) Obtained by inverting the other side of the figure and overlapping it. The situation is shown in FIGS. 7 to 1o.

In Figure 7, the lower part -73 indicated by the solid line is shown in Figure 6 (-).
The A1-A21 plane shown by is shown, and the portion of the upper half 2 shown by the dashed dotted line shows the El-F2 cross section shown in FIG. 6(b). Also, in Figure 8, the lower part -73 indicated by the solid line is the 6th part.
The C1-02 cross section shown in the figure (,) is represented, and the portion of the upper half 2 shown by the dashed line represents the G1-02 cross section shown in FIG. 6(b). In FIG. 9, the lower half 3 section indicated by the solid line represents the B1-B2 cross section of FIG. 6(a), and the upper half 3 section indicated by the dashed line represents the Fl-F2 section of FIG. 6(b).
It represents a cross section. Furthermore, in Fig. 1, the portion of the lower half 3 indicated by the solid line represents the Dl-B2 cross section of Fig. 6 (-),
The upper -72 part indicated by the dashed line is H in Fig. 6(b).
It represents the l-H2 cross section.

Regarding the left reference hole 16, in FIG. 6 (-) and the cross-sectional view shown at bottom -73 in FIG. The abutment wall surface 16a' is limited to the vicinity of the lower surface of the lower half 3 in the thickness direction of the cassette by the removed portion 16a. The deleted portion 16a is formed in an arc shape only near the contact point between the cylindrical reference shaft 20 and the contact wall surface of the left reference hole 16 shown in FIG. 6(a). Also, in FIG. 6(a), the contact wall surface 16) II on which the cylindrical reference φ [120 abuts in the lateral direction of the cassette is shown below in FIG. 7...-73
As shown in the cross-sectional view shown in FIG. 1, the deleted portion 16b is formed in an arc shape only in the vicinity of the abutting point that is offset toward the rear of the cassette from the center of the left reference hole 16, and the abutting wall surface 16b'
is limited to the vicinity of the bottom surface of the bottom no.-73 with respect to the thickness direction of the cassette. Further, the abutting wall surface 16d in the lateral direction of the cassette on the opposite side is formed so that only the abutting wall surface is convex on the protection plate 17.
The same effect is obtained by limiting the contact portion to the vicinity of the bottom surface of the cassette.

Regarding the right reference hole 116, as shown by the dashed line indicated by -72 in FIG. 6(b) and FIG. The contact wall surface 116a' of the left reference hole 116 is limited to the vicinity of the lower surface of the lower half 3 in the thickness direction of the cassette by the removed portion 116a. Moreover, the deleted portion 116a is the contact wall surface 11 of the cylindrical reference axis 2° and the right reference hole 116 shown in FIG. 6(b).
It is formed in an arc shape only near the point of contact with 6a'. In addition, as shown in FIGS. 6(b) and 72 by the dashed dotted line, the reference hole 116 on the right side is aligned with the base shaft 20 in the left-right direction of the cassette lower knob 3. There is no abutting wall surface that determines the position.

Regarding the left side hole 36, as shown in FIG. 6 (-) and the lower half 3 shown in solid lines in FIGS.
The abutting wall surface 36j of the left hole 36 of the lower half 3, which the rear of the cassette Q abuts, is limited to the vicinity of the lower surface of the lower half 3 in the thickness direction of the cassette by the removed portion 36a. What about the deleted section 36a? Cylindrical shaft 30 and left side hole 36 shown in Figure 46 (,)
It is formed in an arc shape only near the point of contact with the contact wall surface 36a'.

Furthermore, as shown by the lower half 3 shown in solid lines in FIG. 6(-) and FIG. Each of the deleted portions 36b and 36c is formed in an arcuate shape only in the vicinity of the contact point offset toward the rear of the cassette from the center of the left hole 3e, and the contact wall surface 3eb'.

360' is limited to the vicinity of the lower surface of the lower half 3 in the thickness direction of the cassette.

Regarding the right side hole 126, as shown in FIG. ' is limited to the vicinity of the lower surface of the lower half 3 in the thickness direction of the cassette by the deleted portion 126a.

Further, the deleted portion 126a is formed in an arc shape only in the vicinity of the contact point between the circular node @30 and the contact wall surface 126a' of the right hole 126 shown in FIG. 6(b). Also, Fig. 6(b), g
As illustrated by the dashed-dotted line shown in the upper half 2 of Figure 8,
Regarding the right hole 126, there is no abutting wall surface for determining the position of the cassette lower half 3 in the left-right direction by the shaft 30.

As described above, according to this embodiment, the reference axis 2o or the axis 30
Reference holes 16, 116 abut against, abutting wall surfaces 16a', 1s'ki, 116&' within the hole 36°126.

36 a', 36 b', 36 c', 126a
'Deletion section 16a on top.

1 eb, 116a, 36a, 36b, 36c
, 126a only in the vicinity of the contact point, the reference shaft 20 or the shaft 3o and the contact wall surface 16a',
16 b'+116a', 36 a', 36 k/, 3
It becomes possible to limit the contact points with 6c' and 126a' to the vicinity of the bottom surface of the cassette body, thereby avoiding the effects of warping or distortion of the upper half 2 or lower half 3 during molding, and preventing the upper and lower nozzles from being affected. It has a great effect on ensuring the repeatability of the positioning of the reference shaft 20 or shaft 30 installed on the equipment side and the tape sheath, such as being able to avoid variations in misalignment when combining 7, etc., and has the following effects. may also be added. Between the reference holes 16, 116 and the hole 3e, it is necessary to provide as wide a space as possible through which the magnetic tape 16 can pass in order to determine the beginning and end of the tape, and to prevent dust and dirt from entering, it is necessary to ensure a space that is shielded from the outside. In addition, in order to incorporate the photodetector, the reference shafts 2Q and 30 must be made as thick as possible, and the reference holes 16, 116 and 30 must be made as thick as possible to ensure repeatable positioning accuracy of the cassette. 36.126 and reference axis 2o, axis 3o
Point contact is desirable for the abutment part, and it is desirable that the reference holes 16, 116 and the holes 36, 126 have a shape close to a square, which is widely used in so-called compact cassettes with a proven track record. It was necessary to ensure that the maximum amount of tape that could be used to draw seats could be secured as much as possible. The present invention satisfies such conditions and then provides the reference hole 16.
, 116 and holes 36 and 126, and for the reference hole 16, the 11th part shown in No. 61'J(a), and for the reference hole 116, the r2 part shown in FIG. 6(G)), Regarding the hole 36, the part 81 shown in Fig. 6 (-), tl
82 parts as shown in FIG. 6(b) for the hole 126,
It is possible to ensure the wall thickness of each of the 12 parts to a level that does not cause problems in mass production molding, making it easy to mass produce.

This has a very large effect on ensuring product quality. Also, the deletion parts 16a, 1eb, 116a.

360' can be ensured for a long time, and the thickness of the adjacent wall surface can be maximized to ensure that dirt is not lifted up, which is effective in ensuring the strength and precision of the product.

Also, reference holes 16, 116 and holes 36, 126 are LX 1”
u 2 (β is formed in a relationship of 82, but the one with the larger width, that is, the right reference hole 116° shown in FIG. 6(b) and the hole 126 are generally formed in a square shape, and a cassette half with such a configuration In this case, the reference hole 16 and hole 36 shown in FIG. 6(a) determine the lateral position of the cassette body.
width α1. α2 is the contact wall surface 1ek/.

A method of forming the squares narrower by 16c', 36b', and 36c' than each side of the square has also been adopted in the conventional compact case, /). Reference hole 16 and hole 3 with this shape
6 and 11, and the center of the shaft used for positioning the cassette is deviated to the rear of the center of the cassette front and back direction of the reference hole 16 and hole 36, so the reference hole 16 shown in FIG. 6(a) is used. The hole 36 becomes the p point, and the hole 36 becomes the q point.

Naturally, the reference shaft 16, the shaft 30, and the contact wall surface 1e
s b', 36 b'.

Since the point of contact with 36C' is also offset to the rear of the cassette, the centers of the removed portions 1eb, 36b, and 36c are also offset to the rear, so that the contact wall surfaces 1s1% and 3eW.

36C' is arranged equally in the front and back direction of the cassette with respect to the contact point design value, and the reference shaft 16 and shaft 30
The effect can be seen in improving the flexibility of responding to changes in the shaft diameter.

In this embodiment, the reference nl+ 16 and the shaft 30 are described as being cylindrical, but the same effect can be obtained even if the reference shaft 16 and the shaft 3o are approximately square, which are chamfered or rounded. Things don't wait for words.

In this embodiment, the deletion units 16a, 16b, and 116a.

3.6a, 36b, and 3ec were deleted in an arc shape, but WJ11 Fig. 1saa, 16bb.

It may be formed into a rectangular shape as shown in 36aa, 36bb, and 36cc. Furthermore, in this case, a significant effect can be obtained in manufacturing the mold for the removed portion.

Effects of the Invention The present invention comprises a cassette body having an opening at one end, and at least a pair of substantially square reference holes for positioning the cassette body disposed within the cassette body, and the cassette body is located behind the reference hole of the cassette. The 11111 wall surface is brought into contact with at least one pair of reference 111+ installed on the device side to determine its longitudinal position, and the lateral dimension of the cassette body of only one of the pair of reference holes is determined by By making the reference hole smaller than the lateral dimension of the cassette body, the gap between the reference shaft and the reference shaft installed from the equipment side is reduced, and the reference hole determines the lateral position of the cassette body. This occurs during molding because the reference hole is limited to the section where the reference shaft can come into contact with the inner wall surface of the reference hole, and the contact wall surface within the reference hole is limited to the vicinity of the top and bottom surfaces in the thickness direction of the cassette body. It is possible to suppress variations in the positioning reference part of the cassette body due to distortion and warpage of the upper and lower halves, and to suppress variations in the positioning reference part of the cassette body due to assembly errors of the upper and lower halves.
As a tape cassette for high-density short-wavelength recording in tape recorders and the like, it has excellent positioning reproducibility, can reasonably guarantee compatibility of the tape cassette in mass production, and has the following effects. It is a tape cassette with an external shape that is almost the same as a so-called compact cassette, and it has a function that allows optical detection of the beginning and end of the tape without sacrificing the maximum capacity of the tape that can fit inside the cassette. -In addition to providing a protective wall to prevent dirt and dust from entering the lid, each part has a reasonable wall thickness for molding, and has a lid that is strong enough to withstand accuracy. It is possible to realize a tape cassette. In addition, by deleting a part of the wall inside the reference hole in an arc shape to form a contact wall surface with the reference shaft installed on the side, the contact wall surface can be improved. In addition to ensuring a long effective contact area, it also maximizes the thickness of the wall near the contact area, ensuring that there is no mud during molding, ensuring product strength and precision, and ensuring high mass productivity. A tape cassette can be realized.

Furthermore, by having a reference hole formed such that the center of the wall surface that contacts the reference shaft installed on the equipment side is offset to the rear of the cassette than the center of the inner wall of the reference hole, the reference shaft installed on the equipment side can be easily adjusted. It is possible to realize a tape cassette with a number of features, such as an increased degree of freedom in changing the shaft diameter, and the ability to diversify equipment and reduce equipment costs by sharing nine parts.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the tape cassette already proposed by the present inventors in a closed state, Fig. 2 is a perspective view showing the same in an open state, Fig. 3 is a partial top view showing the inside, and Fig. 4 is a perspective view showing the tape cassette in the closed state. 5 is a side sectional view of the main part showing the correspondence with the equipment side; FIG. 6(a) is a detailed view showing the inside of the tape cassette in the vicinity of the left reference hole according to an embodiment of the present invention; FIG. 6(b) is a detailed view showing the inside near the right standard scale, FIGS. 7 to 10 are cross-sectional views of the reference hole and the light detection hole, respectively, and FIG. 11 is another example. FIG. 1...Cassette body, 2...Cassette upper half, 3...Cassette lower half, 4...U-shaped lid, 16°116...Reference hole, 36 .126
...hole, 20 ... reference axis, 30 ... mark
Axis, 1ea', 16b', 116a'. 36 a', 36 b', 36 c', 126a
'...-=Abutting wall surface, 16a, 16b, 116a, 36
a, 36b, 36c. 126a...Deletion section. Name of agent: Patent attorney Toshio Nakao and 1 other person
1 Figure) -ゝ傌771 ・-shi 3 Figure No. 9
Figure Figure 10/6M 3
36t,” 2z

Claims (3)

[Claims] (1) Consisting of a cassette body with an opening at one end, and at least a pair of substantially square reference holes for positioning the cassette body located within the cassette body, the cassette body having a rear side wall surface of the cassette of the reference holes. At least one pair of reference holes is brought into contact with the reference shaft installed on the equipment side to determine its longitudinal position, and the lateral dimension of the cassette body of only one of the pair of reference holes is set to that of the other reference hole. By making the width smaller than the lateral dimension of the cassette body, the gap with the reference shaft installed from the equipment side is reduced, and the reference hole determines the lateral position of the cassette body. A tape cassette characterized in that the tape cassette has a reference hole in which the abutting wall surface within the reference hole is limited to only the vicinity of the upper and lower surfaces in the thickness direction of the cassette body, and the contact wall surface within the reference hole is limited to the section where the reference hole can come into contact with the inner wall surface of the reference hole. (2) The reference hole has a wall surface formed by removing a part of the wall surface in an arc shape to form a contact wall surface with a reference shaft installed on the equipment side. The tape cassette described in item 1. (3) Claim 1 characterized in that the reference hole is formed such that the center of the wall surface that contacts the reference shaft installed on the equipment side is offset to the rear of the cassette than the center of the inner wall of the reference hole.
The tape cassette according to item 1 or 2.