JP2000123332A - Tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tape cassette incapable of being used after the cassette is loaded by specific times or above on a video recording/reproducing device. SOLUTION: A disk 14b at the upper side of a reel 14 is freely rotatable around a rotary shaft 14a. A movable member 24 is turned by loading the cassette on the recording/reproducing device and returned to the initial state by unloading the cassette. Thereby the disk 14b is rotated by the specific angle by a pin 48 of a driving arm 40. The reverse rotation is prevented by a reverse rotation preventing arm 50. The leader part of the tape 15 at the side of the reel 14 is arranged to be longer so as to reach on the optical path of a tape detecting light 32 at the side of a reel 12 at most under the state pulled out from the reel 14. When the cassette is loaded by specific times or above, a light shielding plate 54 on the disk 14b erected facing to a disk 14c comes to the position of a sign 54b to shield the tape detecting light 34. The tape is pulled out at most from the reel 14 by the rewinding of the tape 15. As the result, the tape detecting light 32 is transmitted through the leader part under the state when the tape is taken up to the reel 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette, and more particularly, to a tape cassette containing a video tape as a recording medium of a video tape recorder or a cleaning tape for cleaning a magnetic head thereof. Regarding cassettes.

[0002]

2. Description of the Related Art As a means for easily cleaning a magnetic head of a video tape recorder, a cleaning cassette in which a cleaning tape is housed in a cassette instead of a video tape capable of recording video and audio is known. I have. A video tape having a certain unevenness on the surface of the video tape itself is used as a cleaning tape, and a video tape on which a certain image such as a description of a cleaning operation is recorded has been commercialized. There are wet and dry cleaning methods.

[0003]

The cleaning cassette removes dirt from the magnetic head by transferring dirt adhering to the magnetic head to the side of the cleaning tape.・ It is clear that cassettes should not be used. As means for confirming this, in the conventional example, a large number of check boxes are provided on the label outside the cassette, and the user is required to check one check box each time the user uses or a predetermined number of uses. If the box is checked, it is recommended that the cleaning cassette be discarded.

[0004] However, such a method is troublesome, and generally no check box is used. In the conventional example in which the video tape itself is a cleaning tape, when the cleaning effect is not apparent on the playback screen,
The cleaning cassette is discarded.

Therefore, even if the cleaning cassette is discarded even though the cleaning tape is still sufficiently usable, or if the cleaning tape itself has already been considerably contaminated so as to contaminate the magnetic head, it is not noticed. May be used. In the former case, it is useless, and in the latter case, the magnetic head is contaminated. Neither is preferred, and it is desirable that after a certain number of uses, it becomes unusable.

When the recording and / or reproduction reaches a certain number of times,
Disabling subsequent recording or playback may also be desired with conventional video cassettes.

Accordingly, an object of the present invention is to present a tape cassette which cannot be used after a certain number of loadings into a video recording / reproducing apparatus.

[0008]

According to the present invention, the counting means counts the number of times of loading / unloading to / from the recording / reproducing apparatus, and after counting a predetermined number of times, the light shielding means sets the tape main body near the first reel. The first optical path of the first tape detection light for detecting the light is blocked. Further, of the tape-shaped medium,
The length of the leader portion on the first reel side is set to the optical path of the second tape detection light for detecting the tape main body on the second reel side in a state where the tape-shaped medium is unreeled from the first reel to the maximum. Keep it long enough to reach.

Thus, when the tape-shaped medium is wound around the second reel after being used a predetermined number of times, all the leader portions of the tape-shaped medium on the first reel side are fed out from the first reel. , And reaches the optical path of the second tape detection light. As a result, even though the tape-shaped medium is on the second reel side, the second tape detection light passes through the leader section, so that the tape traveling device may misunderstand that the tape-shaped medium is on the first reel side. become. As a result, it is physically impossible to run the tape-shaped medium from the first reel to the second reel, and the tape running in the reverse direction cannot be selected. Traveling by the traveling device becomes impossible.

For example, the light shielding means is a means which moves in conjunction with the counting means. The counting means may have a rotating member that rotates in accordance with loading and unloading to and from the tape traveling device, and the light shielding means may be a means that moves in conjunction with the rotation of the rotating member. The rotating member is rotatably mounted on, for example, one rotating shaft of the first reel and the second reel. It is easiest to fix the light blocking means to its rotating member.

The light-shielding means opens the optical path of the first tape detection light by loading / unloading the tape traveling apparatus more than a predetermined number of times, so that the first tape detection light and the second tape detection light are released.
Both the tape detection light passes through the leader section, and the tape traveling device recognizes the cassette as a tapeless cassette. As a result, even if the tape is loaded into the tape traveling device, it is immediately discharged.

By using the first reel as a take-up reel and the second reel as a supply reel, the leader unit on the first reel side is forced to rewind at the end of the reproducing operation.
It is paid out to the reel side. In the forced rewind, the head of the tape traveling device does not come into contact with the tape-shaped medium, so that even if there is a step at the boundary between the tape body and the leader portion on the first reel side, the head of the tape traveling device may be damaged. There is no.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view of one embodiment of the present invention, and FIG.
Shows a plan view thereof. This embodiment is for a video tape recorder of the VHS system.

In the cassette housing 10, two reels 1 are provided.
2 and 14, and a tape (video tape or cleaning tape) 15 is wound between the reels 12 and 14. Generally, the reel 12 is a supply reel of the tape 15, and the reel 14 is a take-up reel. Each reel 1
On both sides of the rotary shafts 12a and 14a, a tape 1
Disks 12b and 12c for preventing lateral displacement of 5; 14b and 14c
Is attached. In the present embodiment, the disks 12b, 1
2c is fixed to the rotating shaft 12a, and the disk 14b is
4a is rotatable with respect to the rotary shaft 1a.
4a. The rotating shafts 12a and 14a are driven to rotate in a predetermined direction by a video tape recorder loaded with the cassette.

The discs 12b and 14b arranged on the upper side are usually transparent so that it is possible to see from the outside how much tape is on which reel 12 or 14. The disks 12c and 14c arranged on the lower side have a large number of rectangular irregularities formed on the peripheral surface. The discs 12c and 14c are locked by a reel lock mechanism to be described later so as not to rotate when being taken out of the video tape recorder, and become free when properly loaded into the video tape recorder. .

The reel lock mechanism includes the posts 16, 1
8, V-shaped angles 20, 22, movable member 24, spring 2
6,28. That is, the rotating shaft 1 of the reels 12 and 14
Two posts 16 and 18 are erected at positions shifted laterally from a line connecting 2a and 14a. Each post 16, 18
, V-shaped angles 20, 22 are rotatably mounted. One arm 20 of the V-shaped angles 20 and 22
a, 22a are sharpened, and the disks 12c, 1
4c. The other arms 20b and 22b of the V-shaped angles 20 and 22 extend toward the center and face each other.

A movable member 24 rotatable around a line parallel to a line connecting the reels 12 and 14 is attached to the housing 10 near the ends of the arms 20b and 22b. The movable member 24 has an L-shape in which a vertically rising standing plate and a horizontally extending horizontal plate are connected to a rotating shaft serving as a rotation center, and the ends of the arms 20b and 22b substantially contact the side surfaces of the rising plate. .

The V-shaped angle 20 is urged counterclockwise (FIG. 2) by a coil spring 26,
2 is urged clockwise (FIG. 2) by a coil spring 28. When these springs 26 and 28 are detached from the video tape recorder, one of the arms 20 a and 22 a of the V-shaped angles 20 and 22 is connected to the disk 1.
The reels 2 and 14 enter the recesses 2c and 14c so that the reels 12 and 14 do not easily rotate.

When loaded into a video tape recorder (not shown), the pins in the video tape recorder push up the horizontal plate of the movable member 24 to move the movable member 2 about the rotation axis.
Rotate 4. Thereby, in FIG.
The upright plate 4 rotates the arm 20b of the V-shaped angle 20 clockwise and the arm 22b of the V-shaped angle 22 counterclockwise. As a result, the tips of the arms 20a and 22a of the V-shaped angles 20 and 22 come off the recesses of the disks 12c and 14c, and the reels 12 and 14 can freely rotate. Of course, at that time, the drive shaft of the video tape recorder is firmly engaged with the rotating shafts 12a, 14a of the reels 12, 14.

The reel lock mechanism having such a structure is usually provided as a video cassette, and has a known structure.

The tape 15 contained therein generally has transparent leader portions at both ends of the tape so that the video tape recorder can detect that the tape has been supplied or wound up to the end of the tape. Then, the cassette housing 10
Is provided with an opening 30 in the center of the bottom for inserting a reader part detecting optical component (such as a light emitting diode or a light bulb) from the video tape recorder side, and on its side surface, the reader part detecting optical component. (Tape detection light) 32, 34 (FIG. 2) transmitted through the aperture 36, 38 are provided. The tape 1 in which the tape detection lights 32 and 34 are always wound on the reels 12 and 14, respectively.
5, the positions of the openings 36 and 38 are determined.

When the tape detecting lights 32 and 34 are incident on the leader portion of the tape 15, the tape detecting lights 32 and 34 are emitted to the outside from the openings 36 and 38, respectively. 36,38
It is possible to detect whether or not the tape 15 reaches the end based on the intensity or the presence or absence of the light emitted from the tape 15.
5 is checked, and the winding speed on the reels 12 and 14 is controlled. For example, when the tape detection lights 32 and 34 are emitted from both the openings 36 and 38, the video tape recorder determines that no tape is stored in the loaded cassette and ejects the cassette. When the tape detection light 32 is emitted only from the opening 36, the video tape
The recorder determines that the tape 15 has reached the end on the reel 12 side, and prohibits or stops further feeding from the reel 12. Conversely, when the tape detection light 34 is emitted only from the opening 38, the video tape recorder determines that the tape 15 has reached the end on the reel 14 side, and further advances the reel 15 from the reel 14. Prohibit or stop.

The configuration of the characteristic portion of this embodiment will be described. In this embodiment, as clearly shown in FIG.
A large number of saw teeth are formed on the periphery of the disk 4b, and each time the disk drive mechanism described later loads the cassette housing 10 into the video tape recorder, the disk 14b is rotated clockwise by one saw tooth (FIG. 2). It is designed to rotate. The disk drive mechanism also includes a mechanism for preventing the disk 14b from rotating in the reverse direction.

The disk drive mechanism basically includes a drive arm 40 for rotating the disk 14b clockwise (FIG. 2) in accordance with loading on the video tape recorder, and a reverse rotation preventing arm 50 for preventing the disk 14b from rotating in the reverse direction. Consists of

The drive arm 40 has a V
Base arm 4 integrated with the angle 22
2 and a rotating arm 46 rotatably held on a rotating shaft 44 at the tip of the base arm 42. At the tip of the rotating arm 46, a pin 48 is erected. The rotation arm 46 presses the pin 42 against the side surface of the disk 14b around a rotation shaft 44 by a spring (not shown) suspended between the pin 48 and the arm 22a of the V-shaped angle 22. Direction is always energized.

The reverse rotation preventing arm 50 is formed such that one end thereof is rotatably supported by the post 18 and the other end thereof is inserted between the saw teeth of the disk 14b. The reverse rotation prevention arm 50 is free from both the V-shaped angle 22 and the drive arm 40. The anti-reverse arm 50 also
The tip is lightly urged in the direction toward the peripheral surface of the disk 14b by a spring (not shown) suspended between the post 18 and the post 52 adjacent to the post 18. The force of the spring does not hinder the rotation of the disk 14b by the drive arm 40. As shown in FIG. 2, by disposing the oblique side of the sawtooth of the disk 14 b on the front side of the clockwise rotation, the anti-reverse arm 50
Can prevent the disk 14b from reversing even with a light spring biasing force.

On the lower surface of the disk 14b, that is, on the surface facing the disk 14c, there is provided a light shielding plate 54 which can shield the tape detecting light 34 depending on the rotational position of the disk 14c. FIG.
Reference numeral 54a denotes the position of the light-shielding plate 54 at the start of use, reference numeral 54b denotes the position of the light-shielding plate 54 that shields the tape detection light 34, and reference numeral 54c denotes a light shield that has been further rotated and no longer shields the tape detection light 34. The position of the plate 54 is shown. At first, the light shielding plate 54 is, as shown by reference numeral 54a in FIG.
When the disk 14c is rotated at a position where the tape detection light 34 is not blocked and the disc 14c is rotated by a certain number of times of loading into the video tape recorder, the tape detection light 34 is moved to a position where the tape detection light 34 is blocked as indicated by reference numeral 54b. ,video tape·
When the recorder is loaded a predetermined number of times, it moves to a position where the tape detection light 34 is not shielded, as indicated by reference numeral 54c.

In the tape 15 of this embodiment, the leader portion on the reel 14 side is made longer than usual. FIG. 3 shows the tape 1
5 is a development view. 60 is a leader section on the reel 12 side,
62 is a magnetic medium portion (in the case of a cleaning tape,
A cleaner section 64 is a leader section on the reel 14 side.
In the present embodiment, when the tape 15 is loaded onto the video tape recorder and the tape 15 is wound around the rotating drum, and the tape 15 is unreeled from the reel 14 to the maximum extent, the leader portion 64 almost moves to the reel 12. , That is, the length of the leader portion 64 is increased such that the tape detection light 32 passes through the leader portion 64. Reel 12
The leader section 60 on the side may have a normal length. It is preferable that no step is provided at the boundary between the reader section 64 and the magnetic medium section 62. This is because if there is a step, the magnetic head may be damaged depending on its size.

The operation of this embodiment will be described. At the beginning of use, the tape 15 has the magnetic medium portion 62 and the tape detection light 3.
2 is shielded, and the tape detection light 34 is in a state of being transmitted through the reader unit 64.

When loaded into a video tape recorder (not shown), the reel lock mechanism releases the rotating shafts 12a and 14a of the reels 12 and 14, as described above. That is, the pins in the video tape recorder push up the horizontal plate of the movable member 24 to rotate the movable member 24 about its rotation axis. 2, the upright plate of the movable member 24 rotates the arm 20b of the V-shaped angle 20 clockwise about the post 16 and the arm 22b of the V-shaped angle 22 about the post 18. Rotate counterclockwise. As a result, the V-shaped angle 20,
The tips of the arms 20a, 22a of the 22 are disks 12c, 14
As a result, the reels 12 and 14 can rotate freely. Of course, at that time, the drive shaft of the video tape recorder is the rotation shaft 12a, 1 of the reels 12, 14.
4a is firmly engaged.

The V-shaped angle 22, especially its arm 22
In conjunction with the counterclockwise rotation of a, the base arm 42 of the drive arm 40 also rotates counterclockwise about the post 18. Since the rotating arm 46 of the driving arm 40 is urged in the direction of the disk 14b by a spring (not shown), the pin 48 of the rotating arm 46 is in a state of being inserted between the saw teeth of the disk 14b. Thereby, the pin 48 of the rotating arm 46 is moved in accordance with the counterclockwise rotation of the base arm 42.
The disk 14b is rotated clockwise by a predetermined angle. The reverse rotation preventing arm 50 is spring-biased so that its tip enters between the saw teeth of the disk 14b. However, the spring force is not strong enough to prevent the rotation of the disk 14b by the pin 48. Is over the sawtooth on the peripheral surface of the disk 14b.

At this time, the video tape recorder can be operated in the reproduction mode (or the recording mode) in the same manner as a normal tape cassette. Play (or record)
Upon completion, or by stopping during playback (or recording) and instructing rewinding, the tape 15
Is wound up. When the leader section 64 reaches the optical path of the tape detection light 34, the rewinding stops.

The movable member 24 returns to its original position when it is taken out from a video tape recorder (not shown).
Accordingly, the V-shaped angles 20 and 22 fix the rotating shafts 12a and 14a of the reels 12 and 14, respectively. At the same time, the arm 22a of the V-shaped angle 22 rotates clockwise, and accordingly, the base arm 42 of the drive arm 40 also rotates clockwise. The pin 48 of the rotating arm 46 moves counterclockwise along the peripheral surface of the disk 14b, and at this time, gets over the sawtooth on the peripheral surface of the disk 14b. Since the rotation preventing arm 50 prevents the disk 14b from rotating counterclockwise, the disk 14b does not rotate even when the pin 48 gets over the sawtooth of the disk 14b. The spring urging force of the rotary arm 46 is set such that the pin 48 can easily pass over the sawtooth of the disk 14b.

In this manner, the loading and unloading of the video tape recorder causes the disk 14b to rotate clockwise by a certain angle. The light shielding plate 54 is initially unrelated to the tape detection light 34 for detecting the end of the tape 15,
Although it was at the position indicated by reference numeral 54a in FIG. 2, if the loading (and unloading) to the video tape recorder was repeated a certain number of times (for example, 50 times), the light shielding plate 54 was moved to the position indicated by reference numeral 54b in FIG. To block the tape detection light 34.

When the video tape recorder is operated in the reproduction mode in a state where the tape detection light 34 is shielded by the light shielding plate 54, the reels 12 to 14
Is sent to the tape 15. When the magnetic medium portion 62 of the tape 15 is completely removed from the reel 12 and the tape detection light 32 passes through the reader portion 60, the video tape recorder outputs the magnetic medium portion by the output of the light receiving device of the tape detection light 32. 62, the reproduction mode is stopped, and the tape 15 is moved from the reel 14 to the reel 12.
Rewind at high speed. At the time of rewinding, the video tape recorder checks whether or not the rewinding to the reel 12 can be terminated based on the output of the light receiving device of the tape detection light 34. Since the tape detection light 34 is shielded by the light shielding plate 54, even if the magnetic medium unit 62 is completely taken out of the reel 14 and the tape detection light 34 enters the reader unit 64, the video tape recorder may be used. Cannot detect this, and continues rewinding from reel 12 to reel 14. Finally, the tape 15 is completely
When the video tape recorder is taken out from the reel 4, the video tape recorder stops winding on the reel 12 due to the load due to the end of the tape 15 being fixed to the reel 14. At this point, the reader section 64 has reached the optical path of the tape detection light 32. At the time of rewinding, since the tape 15 is not in close contact with the rotary head (although it is completely separated from the rotary head in the old model), there is a slight step at the boundary between the magnetic medium section 62 and the reader section 64. However, it does not damage the rotating head.

In this state, the cassette housing 10 is
When the disk 14b is taken out of the tape recorder and loaded for reproduction, as described above, the disk 14b rotates by a predetermined angle, and the light shielding plate 54 also moves clockwise. At this time, the light shielding plate 54
May be either a position where the tape detection light 34 is blocked or a position where the tape detection light 34 is not blocked. In the former case, the light-shielding plate 54 moves to a position where the tape detection light 34 is not shielded by repeating the removal and loading from the video tape recorder.

When the tape detection light 34 is shielded by the light shielding plate 54, the tape detection light 32 passes through the leader portion 64 of the tape 15, so that the video tape recorder uses the magnetic medium portion 62 of the tape 15 It is determined that it is on the reel 14 side. In this state, the playback mode (reel 12
From the reel 14 to the reel 14) cannot be selected, and only rewinding (the tape 15 from the reel 14 to the reel 12) can be selected. But actually, tape 1
Since 5 has reached the end on the reel 14 side, rewinding is impossible. Therefore, the video tape recorder immediately stops the rewinding operation in response to the user's rewinding operation. That is, the feed of the tape 15 cannot be substantially operated.

In a state where the tape detection light 34 is not shielded by the light shielding plate 54, both of the tape detection lights 32 and 34 pass through the reader unit 64 and enter the corresponding light receiver, so that the video tape recorder has: It is determined that no tape exists in the loaded cassette, and the cassette is ejected as it is. That is, it cannot be used.

As described above, in this embodiment, the video
After loading and unloading to and from the tape recorder have been repeated a predetermined number of times, the tape recorder becomes substantially unusable. For example, by applying the present invention to a cleaning cassette for cleaning a magnetic head, it is not necessary for the user to separately count or store the number of times of use, and the operability is significantly improved.
Of course, a general tape cassette can also be applied to applications in which the number of uses is to be limited.

In this embodiment, on the winding lease 14 side,
Although the tape detection light 34 is shielded, it is apparent that a similar member may be provided on the supply reel 12 side. However, in that case, in a state where the tape detection light 32 is shielded,
The playback mode continues until the end of the tape 15, and if there is a step at the boundary between the reader unit 60 and the magnetic medium unit 62, the step may damage the magnetic head. Therefore, it is preferable to provide the light shielding plate 54 on the take-up reel 14 side as in the above embodiment.

When loading and unloading to and from the video tape recorder are performed in a state where the disk 14b becomes unusable, the disk 14b rotates each time. The light-shielding plate 54 may eventually contact the tape 15 and attempt to cross the tape 15 and damage the tape 15. For this purpose, the light-shielding plate 54 may be easily tilted in a direction in which the light-shielding plate 54 is in close contact with the disk 14b due to an obstacle. However, since no further use is assumed, there is no problem even if the tape 15 is damaged.

Next, another configuration example of the light-blocking member that moves in conjunction with the disk 14b to block the tape detection light 34 will be described. 4, 5 and 6 are partial plan views of FIG.
Shows a perspective view corresponding to FIG. The same components as those in the embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals. FIG.
Here, the tape 15 is omitted.

The post 70 is located near the side wall of the cassette housing 10.
And the arm 72 is disposed so as to be rotatable about the post 70. At the tip of the arm 72, a pin 74 that comes into contact with the peripheral surface of the disk 14b is set up. The arm 72 includes a spring 76
As a result, the pin 74 is always urged in the direction in which it comes into contact with the peripheral surface of the disk 14b. A second arm 80 is rotatably mounted on a rotation shaft 78 in the middle of the arm 72. Arm 8
The leading end of the “0” is curved so as to be movable along a partition wall 82 that reinforces a corner portion including the opening 38 of the cassette housing 10. The arm 80 is urged by a spring 84 so that the tip of the arm 80 is always pressed against the partition wall 82.

The disk 14b has a slit 86 for guiding the pin 74 of the arm 72. The slit 86
Initially, it is formed so as to approach the center of the disk 14b and then move away from the center. Instead of forming the slit 86, a notch obtained by cutting the outer portion from the disk 14b may be used.

FIG. 4 shows that at the beginning of use, the disk 14b and the arms 72 and 80 have the positional relationship shown in FIG. In this state, the pin 74 is in contact with the peripheral surface of the disk 14b, and the tip of the arm 80 is at a position away from the tape detection light 34.

When loading and unloading to and from the video tape recorder is repeated a predetermined number of times, the disk 14b rotates and the slit 86 rotates to the position of the pin 74 as described above. Then, the pin 74 enters the slit 86,
The arm 72 rotates clockwise around the post 70, and the tip of the arm 80 approaches the position where the tape detection light 34 is shielded by the partition wall 82, and finally, as shown in FIGS. It reaches the position where the tape detection light 34 is shielded.

When loading and unloading to and from the video tape recorder are repeated, the disk 14b further rotates.
At this stage, since the slit 86 is formed so as to move away from the center of the disk 14b, the arm 72 rotates clockwise about the post 70, and as a result, the arm 80 rotates.
Returns to a position where the tape detection light 34 is not shielded, as shown in FIG.

When loading and unloading to and from the video tape recorder are repeated a predetermined number of times in the same manner as in the first embodiment, the tape detection light 34 is blocked, and further, loading to the video tape recorder is performed. Is repeated a predetermined number of times, the tape detection light 34 enters a transmitting state. Therefore, similarly to the first embodiment, the tape cassette of this embodiment can be disabled after a predetermined number of uses.

When loading and unloading to and from the video tape recorder in a state where the disk 14b becomes unusable, the disk 14b rotates each time. Pin 74 is slit 8
When the disk 14b reaches the end of 6, the disk 14b cannot physically rotate. If the driving force of the driving arm 40 is weakened, the rotation by the driving arm 40 only idles, and there is no particular obstacle.

In each of the above embodiments, the disk 14b is
4a is freely rotatable, but like the existing one,
That is, a disk (with a smaller radius) similar to the disk 12b of the other reel 12 is fixed to the rotating shaft 14a,
On top of that, a rotating shaft 14
a may be rotatably mounted.

[0052]

As can be easily understood from the above description, according to the present invention, the tape cannot be run after a certain number of loadings on the video tape recorder, and as a result, the tape cannot be used. become. So, for example, in the case of a cleaning cassette,
Use can be reliably stopped, and usability is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of the present invention.

FIG. 2 is a plan view of the present embodiment.

FIG. 3 is a development view of the tape 15;

FIG. 4 is a plan view of a modified portion of the second embodiment of the present invention.

FIG. 5 is a plan view during the operation of the second embodiment.

FIG. 6 is a plan view at the end of operation of the second embodiment.

FIG. 7 is a perspective view corresponding to FIG.

[Explanation of symbols]

 10: Cassette housing 12, 14: Reel 12a, 14a: Rotating shaft 12b, 14b: Disk 12c, 14c: Disk 15: Tape 16, 18: Post 20, 22: V-shaped angle 20a, 20b: Arm 22a, 22b : Arm 24: movable material 26, 28: coil spring 30: opening 32, 34: tape detection light 36, 38: opening 40: drive arm 42: base arm 44: rotating shaft 46: rotating arm 48: pin 50 : Reverse prevention arm 52: Posts 54, 54 a, 54 b, 54 c: Light shielding plate 60: Leader 62: Magnetic medium (or cleaner) 64: Leader 70: Post 72: Arm 74: Pin 76: Spring 78: Rotation Shaft 80: Arm 82: Partition wall 84: Spring 86: Slit

Claims (6)

[Claims] 1. A tape-shaped medium having transparent leader portions on both sides of an opaque tape main body, and the first and second leader portions at both ends of the tape-shaped medium are fixed and the tape-shaped medium is wound.
A reel and a second reel; counting means for counting the number of times of loading / unloading to / from a tape traveling device for running the tape-shaped medium; when the counting means has counted a predetermined number of times, the tape main body near the first reel And a light-shielding means for shielding the optical path of the first tape detection light for detecting the length of the tape-shaped medium. In the extended state,
A tape cassette characterized in that it is long enough to reach an optical path of a second tape detection light for detecting the tape main body on the second reel side. 2. The tape cassette according to claim 1, wherein said light shielding means is means for moving in conjunction with said counting means. 3. The apparatus according to claim 1, wherein said counting means has a rotating member which rotates in accordance with loading / unloading of said tape traveling device, and said light shielding means moves in conjunction with rotation of said rotating member.
The tape cassette according to the above. 4. The tape cassette according to claim 3, wherein the rotating member is rotatably mounted on one of the rotation shafts of the first reel and the second reel. 5. The tape according to claim 1, wherein the light-shielding means opens the optical path of the first tape detection light by loading / discharging the tape traveling device more than the predetermined number of times. ·cassette. 6. The tape cassette according to claim 1, wherein the first reel is a take-up reel, and the second reel is a supply reel.