JPH03224183A - Magnetic tape cassette - Google Patents

Abstract

PURPOSE:To surely perform recording and/or reproducing by individually shakably providing a pair of tape guide members, which guide a recording medium like a tape so that it is helically wound around a head drum, on the inside of an aperture part to which the head drum is inserted. CONSTITUTION:An aperture 5 to which the head drum provided with a rotary head is inserted is provided, and a pair of tape guide members 24 and 25 which guide a recording medium T like a tape to helically wind it around the head drum are arranged individually shakably on the inside of the aperture part 5. Consequently, the pair of tape guide members 24 and 25 are moved in accordance with the head drum even in the case of the difference of a swing angle, an azimuth angle, or the like of the drum when the head drum is inserted to the aperture part 5, and the recording medium T like a tape is accurately slid on the peripheral surface of the head drum. Thus, recording and/or reproducing is surely performed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic tape cassette in which a tape-shaped recording medium is wound and housed. The present invention relates to a magnetic tape cassette which is wound around a magnetic tape and is used for helical scan recording and/or reproduction using a rotary head.

[Summary of the invention]

A magnetic tape cassette according to the present invention has an opening into which a head drum is inserted, and inside this opening, a pair of tape guide members are respectively provided for guiding a tape-shaped recording medium to be wound helically around the head drum. The tape guide member is made to be able to swing and move separately, so that when the head drum is inserted into the opening, both tape guide members come into contact with each other so as to follow the circumferential surface of the insertion portion of the head drum, and the tape-shaped recording medium The recording head is brought into precise sliding contact with the circumferential surface of the head drum to ensure recording and/or reproduction, thereby improving reliability.

[Conventional technology]

Conventionally, in order to make a helical scan type recording/playback device more compact, a part of the head drum with a rotating head was inserted into the front opening of the cassette case, and then wrapped around the circumference of the head drum and stored inside the cassette case. A tape cassette in which a tape-shaped recording medium, that is, a magnetic tape, is brought into sliding contact has been proposed.

Such a tape cassette is provided with a tape guide having a recess on the front side inside the front opening of the cassette case, and this recess receives the head drum.
The magnetic tape is wound helically around the head drum by inclined guides formed on the left and right sides of this concave portion, in which the angles of inclination are opposite to each other. The head now runs diagonally with respect to the magnetic tape, and helical scan type recording and/or reproduction is performed.

In a tape cassette constructed as described above, a tape guide having an inclined guide is molded separately from the cassette case and is incorporated inside the opening of the cassette case, as disclosed in Japanese Patent Application Laid-Open No. 6473584. It is proposed in the official gazette.

[Problem to be solved by the invention]

In such a tape cassette, the tape guide disposed inside the front opening of the cassette case may be molded integrally with the cassette half constituting the cassette case. Even in the tape guide proposed in Japanese Patent No. 73584, which is formed separately, it is attached and fixed to the cassette half.

That is, on the inner surface of the opening side of one cassette half (lower half), the center of this separate tape guide is engaged with the center pin, and the both sides are engaged with the regulating surface or engagement pin. It is incorporated in an immovable state.

Therefore, there is a difficulty in receiving the head drum inserted into the opening of the tape cassette into the tape guide.

In other words, since the tape guide is fixed to the cassette case, if there is a misalignment when loading the tape cassette into the recording/playback device, or if the head drum is slightly tilted, the head drum will not move properly to the cassette case. Even if the magnetic tape is inserted into the opening of the case, it does not come into contact with the tape guide in the normal state, and the sliding contact of the magnetic tape with the circumferential surface of the head drum becomes unstable, causing problems in recording and/or playback. There is a problem.

The present invention has been made in view of this point, and the tape guide member is moved to follow the inclination of the head drum to form an ideal tape path with respect to the head drum, thereby ensuring recording and/or playback. It is an object of the present invention to provide a tape cassette that can be used for various purposes.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an opening in the front side of a cassette case into which a head drum is inserted, and a tape-shaped recording medium wound and stored inside the cassette case is inserted into the opening. In a magnetic tape cassette that is helically wound around a head drum to be inserted and is used for helical scan recording and/or playback by a rotating head equipped with the head drum, the inside of the opening of the cassette case. Furthermore, a pair of tape guide members for guiding a tape-shaped recording medium so as to be wound helically around a head drum are separately arranged to be able to swing and move in the lateral direction.

[Effect]

According to the present invention configured in this manner, when the head drum is inserted into the opening of the cassette case and pressed into contact with the tape guide member, the tape guide member is swingable, so that the head drum is The tape-shaped recording medium is brought into contact along the circumferential surface of the head drum, forming an ideal tape path with respect to the head drum, and the tape-shaped recording medium is brought into precise sliding contact with the head drum, ensuring that recording and/or playback can be performed reliably. .

〔Example〕

Hereinafter, an example of a tape cassette to which the present invention is applied will be described with reference to FIGS. 1 to 10. The tape cassette of this example is constructed to be extremely small.

In FIGS. 1 to 10, (1) generally indicates the case of a tape cassette that stores a magnetic tape for recording and reproducing PCM signals, and this cassette case (1) is connected to the upper half (2). and the lower half (3), and then tighten the screws (
4), tighten and combine both halves (2).

It is constructed by rotatably supporting a lid (6) that opens and closes an opening (5) formed on the front side of (3).

Inside this cassette case (1), that is, the upper and lower halves (2),
(3) In between are the hub drive shaft insertion holes (2a) and (2
b) and (3a).

A pair of both hubs (7) arranged corresponding to (3b), (
8) A pinch roller that also serves as a guide roller is housed with the magnetic tape T wound therebetween, and a portion thereof is placed in the front opening (5), and is rotatably supported on both sides of this opening (5). It is made to be exposed in a stretched state through (9) and (10).

Also, inside this cassette case (1) are both hubs (7),
(8) is equipped with a brake mechanism (11) that operates the brake when not in use, and the cassette case (1
), there is an accidental erasure prevention mechanism (12) located at both rear corners and communicating with both the upper and lower halves (2) and (3).
, (13) are arranged, and positioning reference holes (14) are provided on both sides of the front and rear in the front and back direction of the center and in the rear and lateral directions.
(15), (16), and (17) are provided, and a plurality of required detection holes (1B) and (1
9) is formed, and grip parts (
20) and (21) are formed.

In addition, the lid (6) that opens and closes the front opening (5) of the cassette case (1) has changer retaining parts (23) C (23a), (
23b), (23c).

(23d)) is provided.

In the tape cassette constructed as described above, the magnetic tape T housed in the cassette case (1) is recorded and/or reproduced using a helical scan method using a rotating head.

That is, as shown in FIG. 6, the rotary head (41) is rotated at a predetermined angle with respect to the head drum (42), and the head drum (42) is rotated with respect to the cassette case (1). A magnetic tape T is partially inserted into a front side opening (5) opened by rotating the lid (6) upward or downward, and is stretched across the opening (5). When the rotary head (41) rotates, an inclined track is formed that diagonally crosses the magnetic tape.

At this time, in order to ensure that the magnetic tape T is in helical sliding contact with the head drum (42), in this example, as shown in FIGS. 7, 9, and 10, the cassette case (1) is
A pair of tape guide members (24) and (25), the guide portions of which are inclined in opposite directions, are inserted into the insertion portion of the head drum (42) in the opening (5) of the pinch roller (9).
), (10) are arranged so as to be able to swing and move laterally, facing each other, and by inserting the head drum (42) into the opening (5), the head drum (
The head drum (42) comes into contact with the circumferential surface of the head drum (42).
The magnetic tape T is sandwiched and guided between the magnetic tape T and the circumferential surface of the magnetic tape 2).

In addition, as shown in Figs. 6 and 10, the head drum (
42) have openings (5) for the cassette case (1) on both sides.
Both wing guides (43) and (44) inserted between the pinch rollers (9) and (10) and the tape guide members (24) and (25) are provided on both sides of the Guide (43), (44)
A roller (43a) is attached to the front end of the roller.

(44a) is attached and pressed into contact with the magnetic tape T, and the magnetic tape T is moved to the tape guide member (24).
, (25).

These wing guides (43), (44) have support pieces (26), (27) on the inside of the opening (5) of the cassette case (1), and these support pieces (26),
(27) and a guide protrusion (28) for preventing tape extrusion located between the pinch rollers (9) and (10),
(29).

In the tape cassette constructed as described above, the tape guide members (24) and (25) disposed in the front opening (5) of the cassette case (1) are shown in FIGS. 1 to 4.
This will be explained in more detail with reference to the drawings.

Both tape guide members (24) and (25) are arranged symmetrically on both sides of the front opening (5) of the cassette case (1), and the guide portions are inclined in opposite directions.

That is, the inner surfaces of both tape guide members (24) and (25) have a curved arc shape with a diameter slightly smaller than the diameter of the head drum (42), and are formed as inclined surfaces in opposite directions in the vertical direction. The support edges (24a), (24b) and (2) of the protrusions are arranged at intervals slightly wider than the width of the magnetic tape T.
5a) and (25b) are formed, and guide surfaces (24c) and (25c) are formed between the upper and lower support edges, and the front side continuous with these inclined guide surfaces (24c) and (25c) is They are formed as vertical cylindrical guide surfaces (24d) and (25d). In addition, a supporting edge (24a),
(24b) and (25a).

(25b) has a cylindrical guide surface (24d) and a front end of (25b).
5d) extends slightly forward and receives the receiving edge (24a+)
, (24b+) and (25a I) , (25b r
), and engagement protrusions (24az), (24bz) and (25a2) are formed on the upper and lower opposing surfaces of this receiving edge.
.

(25b,) is formed. Furthermore, receiving edges (24a + ), (24b + ), and (25
Pressing edge (24e) corresponding to aυ, (25b+)
, (24f), (25e) and (25f) are formed, and recesses (24e I) and (24f
+ ), (25e I) and (25r, ) are formed.

The tape guide members (24) and (25) are provided with bearing brackets (24g) and (25g) protruding from the outer surfaces of the guide surfaces (24c) and (25c). The holes (24g+) and (25g,) are formed as horizontally long holes, and the axial holes (24g+) and (25g,)
On the inner circumferential surface of aυ, there is a protruding shaft support edge (
24az) and (25az) are formed.

The tape guide members (24) and (2) configured in this way
5) is a shaft (131) and (132) protruding from both sides of the front opening (5) of the cassette case (1), that is, the front opening forming surface of the lower half (3). Bearing bracket (24g) and (25g) and bearing (24g+) and (25g)
g + ) and insert the lower surface side into the shaft (131).
and a mounting piece (133) formed around the base of (132).
and (134), the tape guide member (
The lower surfaces of 24) and (25) are supported in a floating state at a required interval from the inner surface of the lower half (3), and are connected to the shaft (131) and (
132), and can also tilt in the lateral direction using the contact point between the shaft hole (24g+), the shaft supporting edge (24az) of (25aυ), (25gg), and the shafts (131) and (132) as a fulcrum. , i.e. swinging and horizontally elongated holes (24g+) and (25g+)
horizontal movement is possible.

One end of both tape guide members (24) and (25) is attached to a support portion (1) that is erected on the inner surface of the lower half (3).
springs (135) and (136) supported by
The upper surface sides of the bearing brackets (24g) and (25g) are biased towards the center of the opening (5) by the retaining pieces (137) formed on the inner surface of the upper half (2) and (
138) so that the upper surfaces of both tape guide members are separated from the inner surface of the upper half (2).

In this way, the front side opening (
5) both tape guide members (24) disposed on both sides of the tape guide member (24).

On the front side of (25), a magnetic tape T stretched between pinch rollers (9) and (10) which also serve as guide rollers is slid into contact.

That is, the magnetic tape T has pinch rollers (9), (10)
Support pieces (26), (27) and guide projections (28) in between.

The vertical cylindrical guide surface (24) of both tape guide members (24) and (25) is stretched through the inside of (29).
d) and a supporting edge (24a) in sliding contact with (25d);
(24b) and (25a).

Receiving edge (24a+) of the front extension of (25b), (2
Between 4bυ and (25a+), (25b+), there is an engaging protrusion (24az), (24bz) and (25az),
(25bz) is held in a pinched state.

Therefore, the magnetic tape T is pinch rollers (9) and (10).
) Even if the tape becomes loose between the tape guide members (24) and (25), it will not come off.

Therefore, when the tape cassette containing the magnetic tape T is loaded into a recording/reproducing device for recording or reproducing, the lid (6) of the cassette case (1) is rotated in the opening direction and the opening is opened. (5) is opened, and in this state the head drum (42) is connected to both wind guides (43) and (44).
) and are inserted into the opening (5) in sliding contact with the magnetic tape T, and both wind guides (
The front ends of 43) and (44) are also support pieces (26).

(27) and the guide projections (28) and (29).

The head drum (42) can swing and move laterally within the opening (5) of the cassette case (1).
That is, the support edges (24a) and (2) of both tape guide members (24) and (25) are in a substantially freely movable state.
4b), (25a) and (25b),
Depending on the position and orientation of both tape guide members (24) and (25), the head drum (42) is inserted to a predetermined position by first coming into contact with either the front end surface side or the rear end surface side of the supporting edge. Then, since the one side that came into contact with the tip is pushed, the shafts (131) and (132) rotate around the shaft support, and the other side also comes into contact with the circumferential surface of the head drum (42). Become.

In addition, both tape guide members (24) and (25) have the head drum (42) at the supporting edges (24a) and (24b).
If the upper or lower sides of (25a) and (25b) come into contact with each other first, what is pressed on the other side will cause the shaft support edge (24az) of the bearing brackets (24g) and (25g) to ), (25gg) axis (131),
(132) as a fulcrum, and the other side also comes into contact with the circumferential surface of the head drum (42).

Also, if the distance between the tape guide members (24) and (25) is narrow, the insertion of the head drum (42) will cause the tape guide members (24) and (25) to close together with the spring (135). The shaft (136) resists the elasticity of the shaft (136).
1) and (132) by the horizontally elongated shaft holes (24g, ) and (25g+) of the bearing brackets (24g) and (25g), and the supporting edges (24a), (
24b), (25a), and (25b) are brought into contact with the circumferential surface of the head drum (42).

In this way, both tape guide members (24) and (25) are connected to the head drum (42) at the opening (5) of the cassette case (1).
), supporting edges (24a), (24b) and (25a) are formed on the circumferential surface of the head drum (42).
, (25b) are securely abutted at their front and rear ends.

On the other hand, the front ends of both wing guides (43) and (44), that is, the rollers (43a) and (44a) are connected to the support piece (26).
), (27) and the guide projections (2B), (29), the flange (43b) is brought into rolling contact with the magnetic tape T and pivotally supports the rollers (43a) and (44a). , (43c) and (44b).

(44c) is the pressing edge of both tape guide members (24) and (25) (24e), (24f) and (25e),
(25f), and its concave portions (24e+), (24
ft), (25e+), and (25f +), both tape guide members (24) and (25) are held parallel to the head drum (42) in the front-rear direction.

That is, when the head drum (42) is set in the opening (5) of the cassette case (1), both tape guide members (24) and (25) press the pressing edges (24e) and (24).
f) and (25e).

Both wing guides (43) and (44) come into contact with (25f) to determine the azimuth direction, and the head drum (4
2) are supporting edges (24a), (24b) and (25a)
), (25b) to determine the tilt direction, and in this state the magnetic tape T touches the supporting edge (24
a) between (24b) and (25a).

(25b) is in sliding contact with the vertical cylindrical guide surfaces (24d) and (25d) along the inclined guide surfaces (24c) and (25c), and is set at the ideal tape path position with respect to the head drum (42). be done.

In addition, the magnetic tape T stretched between the pinch rollers (9) and (10) has the receiving edges (24a+), (24b+) and (
There is a locking protrusion (24az) between (25a+) and (25b+).
) , (24bz) and (25az) , (25bz)
The head drum (
42) is inserted into the opening (5), slides into contact with the circumferential surface thereof, and is pushed into the opening (5), whereby the supporting edges (24a) of both tape guide members (24) and (25) ),
(24b) and between (25a) and (25b), the supporting edges (24a) of both tape guide members (24) and (25) will surely follow the inclined guide surfaces (24c) and (25c). , (24b) and (25a).

There is no risk of the magnetic tape T being pinched at the contact portion (25b) against the head drum (42), that is, the chucking portion, and the magnetic tape T runs smoothly along the above-described tape path.

Note that in both tape guide members (24) and (25) that form the tape path as described above, the vertical columnar guide surfaces may be formed by separate columnar bodies and fixed to the cassette case side.

Furthermore, among the upper and lower halves (2) and (3) constituting the cassette case (1) in this example, the upper half (2) extends from the rear wall surface (2c) to both side wall surfaces (2d) and the rear portions (2d) of the upper half (2) and (3). 2dυ and (2a+) are formed at a height approximately half the thickness of the cassette case (1), and both side wall surfaces (2d),
The rear part (2d+) of (2d).

The surfaces except (2a+) are formed at a height approximately equal to the thickness of the cassette case (1), that is, at a height that forms the entire side surface. On the other hand, the lower half (3) extends from the rear wall surface (3C) to the rear wall surface (2d+) on both sides of the upper half (2), the rear wall surfaces (3d) on both sides corresponding to (2d+), and (3a) the cassette case (1). The height is approximately half the thickness of the rear wall on both sides (3d).

No wall surface is formed on both sides except for (3d), and the part excluding the rear part, that is, at least the insertion hole (3a) for the hub drive shaft.
, (3b) is formed into a flat shape that opens in both directions, and both side wall surfaces (2d) of the upper half (2)
), an engaging stepped portion (2dz) at the end edge of (2d),
(2az) is formed, and this locking step (2dz),
(2dz), retaining step portions (3e1) and (3e2) are formed on both side edges of the lower half (3).

Then, connect these upper and lower halves (2) and (3) to the rear wall surface (2).
b) and (3b) and both side walls (2d), rear part of (2d) (2dl), (2dl) and both side rear walls (3d)
, (3d) and both side wall surfaces (2d) of the upper half (2), edge engagement steps (2d+) of (2d), (2d+) and both side edges of the lower half (3). The cassette case (1) is formed by engaging and combining the engaging step portions (3e+) and (3ez).

When assembling the magnetic tape T into the cassette case (1) formed in this manner, the lower half (3) has no side walls and is flat, so the hub (7) around which the magnetic tape T is wound,
(8) into the hub hole (3a) of the lower half (3), (3
b) can be fitted from the lateral direction without any hindrance, resulting in good workability and automatic assembly, which improves mass production.Furthermore, the cassette case (1) itself can be fitted to the upper half (2). Both side walls (2d), (2d) edge retaining stepped portion (2d+
), (2d+) and the engagement steps (
3e1) and (3ez) are engaged with each other to improve airtightness and strength.

Next, the configuration of the brake mechanism (11) in the tape cassette having the above structure will be explained in more detail with reference to FIGS. 9 and 11 to 13.

A substantially rectangular recess (30) is formed at the rear center of the bottom of the lower half (3), and the brake member (31) is positioned within this recess (30) in the front-rear direction, that is, the hub (7).
(8) It is housed and arranged so as to be movable in the direction toward and away from.

This brake member (31) consists of a flat plate part (31a) along the bottom surface of the recessed part (30), and a vertical projecting wall part (31b) erected at the rear of this flat plate part (31a). 31a) has a pair of claw pieces (31a+) and (31az) corresponding to both hubs (7) and (8), respectively.
is formed protrudingly, and as described later, this claw piece (31a+)
The tips of the hubs (31ag) and (31ag) are pressed against the hubs (7) and (8), thereby locking the hubs.

The hubs (7) and (8) have inner hubs (7a) and (8a) into which the hub drive shafts are inserted and engaged, respectively, and inner hubs (7).
It consists of outer hubs (7b) and (8b) that are movable in the axial direction and engaged in the circumferential direction with respect to a) and (8a), and the claw pieces (31a, ) and ( 31
a t ) are adapted to come into pressure contact with the circumferential surfaces of the inner hubs (7a) and (8a) that protrude from the lower surfaces of the outer hubs (7b) and (8b), respectively.

In addition, in the center of the flat plate part (31a), a pair of left and right notch-shaped guide grooves (32a) and (3
2b) is formed, and correspondingly, guide pins (33a) and (33b) are protruded from the bottom of the recess (30), and guide pins (33a) and (33b) are formed along the guide pins (33a) and (33b). The direction of movement of the brake member (31) is defined by being guided by the grooves (32a) and (32b).

Further, the brake member (31) is provided at the rear of the brake member (31).
1) is provided with a leaf spring (34) for urging the main plate (34a) and an arm cut out from the center of the main plate (34a). (34
b), the main plate part (34a) is the lower half (3)
The arm part (34b) is fitted into the spring storage part (35) provided on the inner surface of the rear wall, and the tip of the arm part (34b) is fitted into the recessed part (36) formed on the back side of the vertical protrusion (31b). As a result, the brake member (31) is always urged forward, that is, in the locking direction where the claw pieces (31a+) and (31a-) are pressed against the circumferential surfaces of the inner hubs (7a) and (7b). ing.

And the vertical protruding wall portion (31b) of this brake member (31)
) is formed on the front side of the central portion thereof with a pressing operation portion (37) for operating the brake member (31) to release the hub lock. This pressing operation part (37) has a side cross-sectional shape of a chevron with a high central part, that is, it has inclined cam surfaces (37a) and (37b) which are symmetrically inclined rearward from the central part toward both the upper and lower sides. Both upper and lower halves (2) and (
When this pressing operation part (37) is pressed by the lock release pin inserted through the insertion hole formed in 3), the brake member (31) is moved rearward, and the hub is unlocked. It is done as follows.

In this example, one of the positioning reference holes of the cassette case, that is, the rear reference hole (15) in the front-rear direction in the center, is used as the insertion hole, so that when the tape cassette is loaded into the cassette tape recorder, This reference hole (15)
A positioning pin (50) on the cassette tape recorder side inserted into the hub serves as a lock release pin, that is, the hub lock of the brake member (31) is released by this positioning pin (50).

In addition, a through hole (38) long in the front-rear direction is formed in the center of the flat plate portion (31a) of the brake member (31) in correspondence with the reference hole (insertion hole) (15). ) is a relief for the device fixing pin (lock release pin) (50) formed from the lower half (3) side.

Furthermore, the flat plate part (31a) of the brake member (31) has a pair of left and right protrusions (39a) and (39b) from its rear part.
are symmetrically extended and protruded in the lateral direction. This protrusion (
39a) and (39b) have the required elasticity, and as will be described later, when the brake member (31) is abnormally operated in an inclined manner during the hub lock release operation, the tip of either side protrusion has a circular shape. When the portion (39a,) or (39b,) comes into contact with the rear edge surface (30a) of the recess (30), it is operated to return to the normal hub lock release state.

Also, in this brake mechanism (11), the upper half (2
) A support column (40) is provided to protrude downward from the inner surface of the brake member (31), and its lower end surface is connected to the flat plate portion (31a) of the brake member (31).
), and the brake member (31) is always regulated and held by this support column (40) so that it does not fall out of the recess (30).

As is clear from the above configuration, the brake mechanism (11) in the tape cassette of the present example operates by applying the biasing force of the leaf spring (34) to the claw piece (31a) of the brake member (31) when the tape cassette is not in use. , ) and (31az) are hubs (7) and (8), respectively.
7a) and (8a), thereby locking both hubs (7) and (8) so that they will not rotate under some impact (see FIGS. 9 and 13A).

When the tape cassette is loaded into the cassette tape recorder, the positioning pin (50) on the tape recorder side is inserted into the reference hole (15) (actually, the cassette case (1)
is lowered and the reference hole (15) is fitted with the positioning pin (50)), and the cassette case (1) is positioned, and at the same time, the hub lock release operation of the brake member (31) is performed.

This hub lock release operation is performed for upper half (2), lower half (
3) can be performed from either side; that is, if the cassette tape is loaded into a cassette tape recorder with the upper half (2) side (so-called side A) facing up as shown in Figure 3, the lower half ( 3) side reference hole (15) presses the inclined cam surface (37b) of the press operation section (37) (lower side in the figure), thereby causing the brake member to close. (31) resists the biasing force of the leaf spring (34) and moves backward, that is, the claw pieces (31a+) and (31az).
Of hubs (7) and (8), hubs (7a) and (8a)
(see Figures 2 and 3 B), and conversely, flip the cassette case (1) over so that the lower half (3) side (so-called B side) is facing up. When loaded into a cassette tape recorder, the device fixing pin (50) consisting of the reference hole (15) on the upper half (2) side allows the inclined cam surface (37
a) is pressed, and this causes the brake member (31) to move rearward against the biasing force of the leaf spring (34) in the same manner as described above, thereby causing the hub (7) and (
8) is unlocked, that is, the hubs (7) and (8) are free to rotate.

In addition, in the hub lock release operation of the brake member (31), since the structure is such that the brake member (31) is operated by pressing a point in the center of the brake member (31),
Sometimes, the brake member (31) does not operate in a well-balanced manner on the left and right, and is moved in an inclined manner as shown by the two-dot chain line in Fig. 12, resulting in a so-called one-sided return situation in which the pawl on one side remains in contact with the hub and does not separate. There is a risk that it will become. In such a case, in the tape cassette of this example, the circular tip portion (39b) of the protrusion on either the left or right side (the right protrusion in the example of Fig. 12) (39b) of the brake member (31) is used.
b, ) comes into contact with the rear edge surface (30a) of the recess (30), and the brake member (31
), both claw pieces (31a, ) and (31az) are attached to the hub (7), respectively.
) and (8), and therefore both claw pieces (31a, ) and (31az) are equally spaced apart from the hubs (7) and (8), that is, the brake member (3
1) is prevented from returning on one side, ensuring that both hubs (7) and (8)
) will be unlocked.

In this manner, the hub is rotated by the drive of the hub drive shaft on the cassette tape recorder side, and the tape is run with the hub (force) and lock (8) by the brake member (31) being reliably released. .

As described above, the tape cassette of this example has a cassette case (
1) Since the hub lock release operation of the brake member (31) can be performed from either the upper half (2) side or the lower half (3) side, the cassette case (1) can be reversed and reciprocating recording can be performed. Compatible with playable double-sided tape cassettes.

In addition, by using the positioning reference hole (15) of the cassette case as the insertion hole for the pin that operates the brake member (31), both the upper and lower halves (2) of the cassette case (1)
Since there is no need to form separate insertion holes in (3) and (3), space can be saved in the design of the cassette case, especially for ultra-compact cassettes with limited space, such as in this example. Effective for tape cassettes. Also, on the cassette tape recorder side, there is no need to provide a lock release pin for operating the brake member (31), and the positioning pin (50) for positioning the cassette case can be used to position the cassette case and brake simultaneously. Parts (31
), the hub lock release operation is performed.
The number of parts on the cassette tape recorder side can also be reduced, contributing to the simplification of the mechanism.

Furthermore, when the brake member (31) abnormally operates in an inclined manner during the hub lock release operation and is about to return to one side, the brake member (31) is returned to normal state due to the cushioning action of either the left or right protrusion (39a) or (39b). Since the hub lock is always reliably released, the hub (7) is returned to the state of
) and (8) have various excellent advantages not found in the past, such as no resistance (smooth rotation and stable tape running guaranteed).

Moreover, in the tape cassette configured in this way,
The hub around which the magnetic tape as a tape-shaped recording medium is wound and its arrangement will be described in more detail with reference to FIG. 14. Since the pair of hubs are formed identically, FIG. Only the hub side is illustrated, and the corresponding symbol on the other hub side is written in parentheses.

Both hubs (7) and (8) are outer hubs (7a) and (
8a) and inner hubs (7b) and (8b), the outer hubs (7a) and (8a) are drum-shaped, and the inner peripheries (7aI) and (8a,) have cylindrical inner hubs (7b). ,
(8b) is fitted so as to be slidable in the axial direction and engageable in the circumferential direction, and the outer peripheral surface (7az) of the outer hub (7a), (8a), and the inner peripheral part (7b of (8a2)) ,),
(8bl) is a drive shaft holding hole into which the hub drive shaft is inserted and engaged.

That is, the outer hub (7a) of the hub (7), (8), (
The inner circumferential portions (7a,), (8a,) of 8a) are provided with engagement recesses (7a,) at required intervals in the circumferential direction, which serve as engagement portions only in the circumferential direction.
7az) and (8a,) are formed. On the other hand, the outer diameter of the inner hubs (7b) and (8b) is that of the cassette case (1).
, that is, insertion holes (2a), (3a), (
2b).

(3b), and the height is slightly larger than the vertical inner width of the cassette case (1), that is, the distance a between the inner surfaces of the upper and lower halves (2L (3)). (7
b) , (8b) outer peripheral surface (7b2) , (8b2
) are formed with engaging protrusions (7b:+) and (8bi) that engage with the engaging recesses (7a3) and (8a3) of the aforementioned outer hubs (7a) and (8a), respectively. As a result, the outer hubs (7a), (8a) and the inner hubs (7b), (8b) are connected to the engagement recesses (7az),
(8a3) and the engaging convex portions (7b3), (8b3) engage each other in the circumferential direction and move integrally,
They are slidable relative to each other in the axial direction. In addition, the inner peripheral portions (7b+) of the inner hubs (7b) and (8b), (
sb+) are formed with retaining protrusions (7ha) and (8b4) at required intervals, which are engaged with the engaging claws of the hub drive shaft, and on both end edges of the inner periphery (7bυ, (8b+)). is a tapered guide surface that slopes inward (7bs), (8bS)
is formed.

Then, the hubs (7) and (8) formed in this way are arranged in the cassette case (1), that is, the upper and lower halves (2).
, (3) through holes (2a), (2b), (3
Inner hub (7b) is attached to the inner circumferential surface of a) and (3b).
, a circular concave stepped surface (8b) with a diameter larger than the outer diameter of the mouth end (
2a+), (2b+), (3a+)+ (3b+) are formed, and inner hubs (7b), (8
By making the circular mouth end of b) fit loosely, the inner hubs (7b), (8b) can be connected to the upper and lower halves (2), (
3) so as to be rotatably supported.

In this way, the insertion holes (2) of the upper and lower halves (2) and (3)
a).

(2b), (3a), (3b) and hub (7)
, (8), the hub (7), (8) is formed.
) fits entirely between the upper and lower halves (2) and (3),
It is supposed to be hidden, and the top and bottom halves (2).

You cannot directly touch the surface of (3) with your fingers.
Therefore, careless rotation by an external hand is prevented, and the tape T wound around it is not subjected to unnecessary slack or tension. In addition, the inner hubs (7b) and (8b) that constitute the drive shaft engagement holes of the hubs (7) and (8) have a larger diameter than the inner diameter of the insertion holes of the upper and lower halves (2) and (3), and have concave stepped surfaces (
3a,) (3bl) are loosely fitted, so that when inserting the hub drive shaft, there is no direct butt.
The hubs (7) and (8) will be inserted smoothly while being guided through the insertion holes of the upper and lower halves (2) and (3).
There is no risk of damaging the hub drive shaft, and the airtightness within the cassette case (1) is maintained, preventing dust from entering and the tape T being reliably protected.

In addition, the inner diameter of the drive shaft engagement holes of the hubs (7) and (8) is the same as that of the insertion holes (2a) and (2) of the upper and lower halves (2) and (3).
b), (3a), and (3b) are directly related (as they can be set, design constraints are reduced and manufacturing is facilitated.

In the tape cassette constructed as described above, an erroneous erasure prevention mechanism (12) is provided in the cassette case (1).

(13) will be explained in detail with reference to FIGS. 15 to 17. Since both prefecture erasure prevention mechanisms are configured identically, only one mechanism (12) is illustrated, and the other mechanism ( 13) is omitted from illustration.

These erasure prevention mechanisms (12) and (13) have sliders (231) for detecting accidental erasure prevention on both rear sides of the cassette case (1) in the thickness direction of the cassette case (1). It is configured to be slidably inserted and held in a fitting hole (232) formed to penetrate therethrough.

The slider (231) is molded from an elastically deformable synthetic resin material, etc., and has a length shorter than the length of the insertion hole (232), the middle part (231a) has a substantially square cross section, and both ends The portions (231b) and (231c) are formed to have a circular cross section, and the opposing surface (231b) in one direction of the intermediate portion (231a)
1a, ) and (231az) are formed so that stopper convex surfaces (234a) and (234b) are located at the center thereof and face each other, and opposing surfaces (231a: +) and (231a,) have substantially hemispherical click stopper projections (235a,), respectively.
) and (235b) are provided protrudingly. These click stopper projections (235a) and (235b) are sliders (
231) shifted from each other at predetermined intervals in the length direction,
Moreover, even when the sliders (231) are reversed, they are arranged so that they are in the same position.

And these click stopper projections (235a)
and (235b), the protruding part surface (235a r ) and (23
5b, ) are formed thin so that they can be elastically deformed to some extent. That is, click stopper abutment (2
By forming counterbore holes (235a) and (235b2) of a predetermined depth from the side facing the protruding side surfaces of 35a) and (235b), the above-mentioned protruding portion surfaces are formed thin.

On the other hand, the insertion hole (232) into which the slider (231) configured as described above is inserted is located at the middle part (2) of the slider (231).
31a) is formed across the upper and lower halves (2) and (3), and this insertion hole (
232) facing in one direction, that is, the slider (23
Upper and lower halves (2) of surfaces (232a) and (232b) opposite to stopper convex surfaces (234a) and (234b) of 1)
) and (3), and the stopper concave portions (236a) and (236b) are formed to face each other, and the stopper convex surface is slidably engaged in the longitudinal direction of the insertion hole (232). There is.

The stroke of the slider (231) is regulated by movably engaging the stopper convex surfaces (234a) and (234b) with the stopper concave portions (236a) and (236b).

Then, the inner wall surface facing the other side of this insertion hole (232), that is, the click stopper projection (2) of the slider (231)
35a) and (235b), the surface (232c) and (
Click stopper recesses (237a) and (237b), in which the click stopper protrusions are engaged, are formed facing each other across the joint between the upper and lower halves (2) and (3) of 232d).

A guide groove (237a,) extending toward the upper half (2) is continuously formed in the click stopper concave portion (237a) corresponding to the click stopper protrusion (235a) on one side, and a guide groove (237a,) extending toward the upper half (2) side is continuously formed. 237
A guide groove (237b,) extending toward the lower half (3) is continuously formed in the click stopper recess (237b) corresponding to b). Both guide grooves are each formed shallower than the glue link stopper recess.

Next, there is an erroneous erasure prevention mechanism (12) constituted by the slider (231) and the insertion hole (232) formed in this way.

The operation of (13) will be explained.

First, when the slider (231) is located above the insertion hole (232) in the thickness direction of the cassette case (1), that is, located on the upper half (2) side, as shown in FIG. 17th
As shown by solid lines in the figure, the stopper concave surfaces (234a) and (234b) of this slider (232) are connected to the insertion hole (232).
) are located in the stopper recesses (236a) and (236b) on the A-7 (2) side, and in this state, the other click stopper protrusion (235b) engages with the other click stopper recess (237b). has been done. And both click stopper projections (235a) and (235b)
) are misaligned with each other, so one click stopper protrusion (235a) cannot be engaged with one click stopper concave surface (237a). 237a + ). In this state, the click stomper protrusion (235a) has a guide groove (237a + ) to which it is pressed.
a, ) has a step with the inner wall surface of the insertion hole (232),
In addition, since this protrusion surface (235a, ) is in an elastic deformation state, an appropriate required pressing force is applied,
Due to this pressing force, the other click stopper protrusion (235b) described above is moved to the other click stopper recess (235b).
7b) and the slider (231) is fitted into the insertion hole (2
32) is reliably held in the upper position.

Next, when the slider (231) is located below the insertion hole (232), that is, on the lower half (3) side, the 16th
As shown by the two-dot chain line in the figure and FIG. 17, the convex surfaces (234a) and (234b) of the
6a) and (236b) on the lower half (3) side, and in this state one click stopper projection (2
35a) is the negative click stopper recess (237a)
is engaged with. The other click stopper projection (235b) is connected to the other click stopper recess (235b).
7b) and is pressed into contact with a guide groove (237b I) that continues from this recess to the lower half (3) side.

In this state, one click stopper protrusion (235a) is engaged and pressed into one click stopper recess (237a) by the action of the other, as in the case of the above-mentioned upper position, and the slider (231) is inserted and inserted. The position is reliably held at the lower position of the term (232).

In such a switching operation of the position of the slider (231), the slider (231) moves toward the click stopper projection (235).
a) and (235b) are click stopper recesses (237
Guide groove (237a,) continuous to a) and (237b)
Since the switch is moved in sliding contact with (237b,), a stable and smooth switching operation is performed. In particular, in this example, the click stopper protrusions (235a) and (235b) are elastically deformed in the pressing direction, so that the slider moves more smoothly and is secured against the click stopper recesses (237a) and (237b). will also be carried out more reliably.

In addition, in this operation of switching the position of the slider (231), the slider (231) is pressed more strongly than necessary, and the click stopper projections (235a), (235b) are moved to the click stopper recesses (237a), ( 237b)
When the stopper surfaces (234a) and (234b) cross over the stopper recess (234a) of the insertion hole (232), the stopper surfaces (234a) and (234b)
34a) and (234b) are abutted against the edges of the stopper recesses (236a) and (236b) of the insertion hole (232), thereby preventing the slider (231) from sliding and preventing the insertion. Falling out of the hole (232) is prevented.

As described above, the slider (231) is attached to the cassette case (1
) is changed relative to the insertion hole (232), and the detection switch detects this change in position via a detection bin, etc., and the two states of erasing enabled state and accidental erasing prevention state are detected. It becomes possible to make a reliable determination.

The erroneous erasure prevention mechanisms (12) and (13) of this example enable the same position switching operation, ie, detection operation, as in the case described above, even when the image is upside down.

In addition, in this configuration, the cross-sectional shape of the slider and the inner shape of the insertion hole are not limited to a rectangular shape, but may be a hexagonal shape or the like, with the stopper means on at least two opposing surfaces, and the stopper means on the other opposing two surfaces.
Any shape may be used as long as the click stopper means can be formed from the surface thereof.

In this way, between the slider that is inserted and slides in the thickness direction of the cassette case and the insertion hole into which this slider is inserted, there is a spacer that prevents the slider from coming off. and a positioning click stopper means that locks at a predetermined switching position between an erasable state and an accidental erasure prevention state, and the click stopper means is formed by connecting a stop part and a guide part. The slider switching operation can be performed stably and smoothly, and the erasing enabled state and erasing prevention state can be easily and reliably set, and if the slider is pressed more forcefully than necessary during this switching operation. Alternatively, even if the click stopper means is worn out, it is prevented from falling off and erroneous erasure can be reliably prevented, thereby providing a highly reliable tape cassette.

Since the tape cassettes constructed as described above are formed to be ultra-compact as described above, there is a risk of them being lost if they are used alone, so when not in use, multiple tape cassettes are stored in a cassette/nod magazine (described later) for preservation.

A device for accurately storing tape cassettes in the cassette magazine and for easily taking them out is provided on the lid (6) for opening and closing the opening (5).

That is, the guide groove (22) provided on the front surface of the lid (6)
) is formed laterally from the center of the lid (6) to either the upper or lower side (downward in this example), and as described later, this guide groove (22) allows the tape cassette to be inserted into the cassette magazine. An insertion direction is defined.

On the other hand, the retaining part (2) provided along this guide groove (22)
3) Pulling out the tape cassette from the cassette magazine
In this example, the first grooves are horizontally arranged between both ends of the lid (6) along the guide groove (22).
- Fourth notch recess (23a), (23h), (
23c).

(23d). That is, first and fourth notch recesses (23a) and (2) are provided at both left and right ends of the front surface of the lid (6).
3d) is formed to be open to the side surface of the lid (6), and second and third notch recesses are formed in the center of the front surface of the lid (6) between both large cutout recesses (23a) and (23d). (23b) and (23c) are provided, and these four notch recesses (23a), (23b), (23c) are provided.
) and (23d) are formed at approximately equal intervals.

FIG. 18 shows an example of a cassette magazine, that is, this cassette magazine (331) has a plurality of storage parts (332) into which tape cassettes are inserted and loaded in the horizontal direction,
Each storage section (332) is partitioned by a partition wall (333). An engagement protrusion (334) is formed in the depth direction at the bottom of each storage part (332).
When the tape cassette is inserted, this engagement protrusion (33
4) so that the guide groove (22) of the lid (6) is engaged with the guide groove (22) of the lid (6).

When inserting this tape cassette, the guide groove (22) of the lid (6) is formed to be offset from the center, so if the tape cassette is reversed and the tape cassette is inserted from the opposite side, the guide groove (22) The groove (22) will not correspond exactly to the engagement ridge (334) and reverse insertion of the tape cassette will therefore be prevented.

In addition, an engagement protrusion (334) is provided at the bottom of each storage section (332).
A slot (335) into which a drawer arm of a drawer device to be described later is inserted is formed along the groove.

The plurality of tape cassettes stored in the cassette magazine configured as described above are inserted into a recording/playback machine together with the cassette magazine, and within the recording/playback machine, the tape cassettes are automatically taken out by a cassette changer system and recording/playback is performed. It will be done.

Fig. 19 shows a schematic configuration of this cassette changer system. In Fig. 19, (336) represents the entire recording/playback machine, and a plurality of tape cassettes are housed in this record/playback machine (336). When the cassette magazine (331) is inserted, the cassette magazine (331) is moved by a predetermined moving mechanism, and one tape cassette is pulled out by the drawer device (337) from the designated storage section (332). When the tape cassette is taken out from the cassette magazine (331) in this way, the cassette case (1) is transported to the drive mechanism section (339) by the transfer device (338) and mounted thereon. 339), the above-mentioned rotating head (41)
is inserted into the opening (5) of the cassette case (1), and a predetermined recording or reproducing operation is performed.

In this cassette changer system, the drawer device (337) for taking out the tape force 771- from the cassette magazine is a drawer that is inserted into the slot (335) of the cassette magazine (331) and operates reciprocally, as shown in FIG. The drawer arm (340) has an arm (340).
40) is formed with a ratchet-like engaging claw portion (340a) that engages with the engaging portion (23) of the lint (6) only in the direction in which the tape cassette is pulled out. As this pull-out arm (340) reciprocates, its engaging claw portion (340a) is moved to the engaging portion (340a) of the tape cassette.
23), and the table chain l- is pulled out from the center magazine (331).

In this operation, in this example, the tape cassette is pulled out by reciprocating the pull-out arm (340) multiple times with small strokes. That is, first, 1 of the drawer am (340)
In the second reciprocating operation, the third notch recess (
The retaining claw part (340a) is hooked on the pull-out arm (340) and the tape cassette is pulled out by about 173 cm.
In the second reciprocating operation, the engaging claw part (340a) is hooked on the second notch recess (23b) of the retaining part (23), and the tape cassette is pulled out again by about 173 degrees.

Then, during the third reciprocating operation of the drawer arm (340), the engaging claw part (340a) is hooked on the first notch recess (23a) of the engaging part (23), and the entire tape cassette is thereby pulled out. That will happen.

The tape cassette pulled out from the cassette magazine in this way is transferred to the drive mechanism section (339) by the transfer device (338) of the cassette changer system as described above.
The recording or reproducing operation is performed here.

As described above, the tape cassette of this example has the drawer arm (340) of the cassette changer on the front of the lid (6).
By forming the engaging part (23) on which the
It can be easily taken out from the cassette magazine (331) and is compatible with a cassette changer system.

In addition, in this example, the retaining portion (23) includes a plurality of cutout recesses (23a) arranged in parallel at approximately equal intervals in the lateral direction of the lid (6).
.

(23b), (23c), and (23d), it is possible to shorten the stroke of one reciprocation of the drawer arm (340) and pull out the tape cassette in multiple strokes, thus making the drawer device (337) smaller. This makes it possible to form a cassette changer system, which in turn leads to miniaturization of the entire cassette changer system.

Further, since the engaging portion (23) is formed on the lint (6), there is no need for a major design change to the conventional tape cassette (it can be easily implemented).

That is, if this retaining part (23) is to be provided on the cassette case (1) side, the space of the cassette case (1) is extremely limited, so it will be difficult to arrange the storage space for the magnetic tape and the arrangement of various detection holes, etc. However, in this example, the retaining part (23) is provided in a so-called empty space on the front of the lid (6), so the design is very difficult. It is easy to implement because it does not affect the design and requires only slight processing on the lid (6).

In this way, by forming the retaining part on the front lid of the cassette case to which the drawer member of the cassette changer is hooked, the tape cassette can be easily taken out from the cassette magazine.

Further, since this engaging portion is formed on the lid attached to the front portion of the cassette case, it can be easily implemented without requiring major design changes to existing tape cassettes.

Although the present invention has been described in detail above, the present invention is not limited to this embodiment, and can be modified in various ways without departing from the spirit of the present invention.

For example, the rollers (43a) and (44a) attached to the front ends of the wing guides (43) and (44) provided on the head drum (42) connect the upper and lower flanges to the wing guides (43) and (44). The cylindrical part which is fixed and in contact with the intermediate tape may be configured as a rotatable roller.

It goes without saying that the present invention can be applied not only to ultra-small tape cassettes but also to large-sized tape cassettes.

〔Effect of the invention〕

As described above, the tape cassette according to the present invention has an opening into which a head tram equipped with a rotating head is inserted, and a tape-shaped recording medium is wound helically around the head drum inside this opening. By arranging the pair of guiding tape guide members so that they can swing independently,
When the head drum is inserted into the opening, the pair of tape guide members can follow it even if there are differences in the drum tilt angle, azimuth angle, guide opening angle, or a combination of these angles. .

Further, the distance between both tape guide members is also determined by the wing guide of the head drum. Both tape guide members come into contact with each other so as to follow the circumferential surface of the insertion portion of the head drum, forming an ideal tape path, and the tape-shaped recording medium is accurately slid onto the circumferential surface of the head drum to wrap the tape-shaped recording medium. Since the center of the corner is held correctly, there is no positional shift of the recording pattern on the tape-shaped recording medium, and recording and/or reproduction can be performed reliably and reliability can be improved.

Furthermore, since the cassette case and the tape guide member are separate bodies, it is possible to select the most suitable material for the tape guide member.

and deformation of the cassette half forming the cassette case,
Since the influence of manufacturing variations is small, dimensional accuracy can be relaxed, and as a result, costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view of the main parts of the tape cassette according to the present invention;
Figure 2 is a cross-sectional view taken along line A-A in Figure 1, and Figure 3 is B in Figure 1.
4 is a perspective view of the tape guide member, FIG. 5 is a perspective view of an example of the tape cassette according to the present invention, and FIG. 6 is a perspective view showing the relationship between the tape cassette and the head drum. , FIG. 7 is a front view of the tape cassette with the lid open, and FIG. 8 is a plan view of the inner surface of the upper half.
Figure 9 is a plan view of the lower half side, Figure 10 is a partially omitted plan view of the lower half side with the head drum inserted, Figure 11 is a perspective view of the brake mechanism, and Figure 12. FIG. 13A is a plan view of the same in the unlocked state. B is a sectional view explaining the operation, FIG. 14 is a sectional view of the hub,
Figure 15 is a perspective view of the slider of the accidental erasure prevention mechanism, Figure 16 is a front sectional view of the accidental erasure prevention mechanism, Figure 17 is a sectional view taken along line C-C in Figure 16, and Figure 18 is a cassette. FIG. 19 is a sectional view of the magazine, FIG. 19 is a schematic diagram of the cassette changer system, and FIG. 20 is an explanatory diagram of the tape cassette drawing operation. In the figure, (1) is the cassette case, (5) is the opening, (24
). (25) is a tape guide member, (24a), (24
b), (25a). (25b) is the supporting edge, (24a+), (24bυ,
(25a+), (25b+) are receiving edges, (24c)
, (25c) is an inclined guide surface, (24d). (25d) is a cylindrical guide surface, (41) is a rotating head, (
42) is the hent drum, (131) and (132) are the shafts, and (135) and (136) are the wings. Agent Hidemori Matsukuma's table power "Ini" sound β, #1 of Kyousai! Saimi Pko Figure 4 - Kei 1's Plane Mouth of Saranegi Figure 1 24a (25a) 4J81 Nagi's A-A section (2) Figure 2 Figure 1O's B-Batr+Wry'a movement Io Yoshibon 1g month 0 Fig. 13 2- Lower half 3- Lower half 7...Haf 15--One act quasi-yo 1-(n Iniko L) 31-m-Fushi one kilogram second 31a, 37b・-I 1# Cutting cam surface 5O---Grain determination hole (072M removed shin 1ff 5 7b 1 W'r surface I of 7 cassette cam Fig. 20 31 Cassette changer system Shoulder diagram Figure 19

Claims (1)

[Claims] 1. An opening into which a head drum is inserted is provided on the front side of the cassette case, and a tape-shaped recording medium wound and stored inside the cassette case is inserted into the opening. In the magnetic tape cassette, the magnetic tape cassette is helically wound around a head drum, and the recording and/or reproduction is performed using a helical scan method by a rotary head provided on the head drum, wherein the opening of the cassette case is A magnetic tape cassette characterized in that a pair of tape guide members for guiding the tape-shaped recording medium so as to be wound helically around the head drum are separately provided inside the head drum and are swingable. 2. The magnetic tape cassette according to claim 1, wherein the pair of tape guide members includes an arcuate tape guide surface that matches the circumferential surface of the head drum. 3. The magnetic tape cassette according to claim 2, wherein the arcuate tape guide surfaces of the pair of tape guide members are sloped surfaces in opposite directions. 4. The magnetic tape cassette according to claim 1, characterized in that the pair of tape guide members have supporting edges of protrusions formed above and below the tape guide surface at intervals wider than the width of the magnetic tape. magnetic tape cassette. 5. In the magnetic tape cassette according to claim 4, the pair of tape guides has a receiving edge that is continuous with the supporting edge of the protrusion and guides the head drum toward the front end side of the opening of the cassette case. A magnetic tape cassette characterized by comprising: 6. In the magnetic tape cassette of claim 1, the pair of tape guide members are located on the front end side of the opening of the cassette case, and have vertical cylinders at both left and right end positions for guiding the introduction and ejection of the magnetic tape. A magnetic tape cassette characterized by comprising a guide section. 7. In the magnetic tape cassette according to claim 6, the vertical cylindrical guide part is provided with a receiving edge having a recess at the top and bottom of the guide member on the end side of the opening of the cassette case, and the head A magnetic tape cassette characterized by being positioned by a wing guide provided on the drum side. 8. In the magnetic tape cassette of claim 1, the back side of the guide surface of the tape guide member is provided with a bearing bracket having a shaft hole that fits into a shaft provided upright on the inner surface of the cassette case. A magnetic tape cassette characterized by: 9. In the magnetic tape cassette according to claim 8, the bearing bracket provided on the tape guide member is provided with a shaft hole that is long on the left and right sides when viewed from the front of the opening of the cassette cassette, and A magnetic tape cassette that is fitted with a shaft that stands upright on the inside, allowing freer movement from side to side than from front to back. 10. The magnetic tape cassette according to claim 8, wherein the bearing bracket provided on the tape guide member has a protruding shaft support edge formed approximately at the center of the inner peripheral surface of the shaft hole,
A magnetic tape cassette, characterized in that the tape guide member is fitted with a shaft provided upright on the inner surface of the cassette cassette so as to be swingable. 11. In the magnetic tape cassette according to claim 1, a spring is interposed between a part of the back surface of the tape guide member and a supporting portion erected on the inner surface of the cassette casing, A magnetic tape cassette characterized in that the tape guide member is biased so as to rotate. 12. A magnetic tape cassette according to claims 1 to 11, characterized in that it is used for recording and/or reproducing digital signals.