JPS6171485A - Tape cartridge - Google Patents

Abstract

PURPOSE:To attain sure lock release by specifying the relation of position between a face receiving a projection at lock release start point of time and a press contact face of one connecting side in press contact onto it. CONSTITUTION:When a brake member 30 is placed at the rear lock position, a press contact face 37 pressing into contact onto a face 42 of a moved projection 36 is formed to the inner face of each connecting piece 14 of a front cover 12. The face 42 is placed to the case rear side from a vertical line V through the center of a shaft 15 of the link piece 14. Further, an imaginary operating line L tying a press contact face 37 and the center of the shaft 15 is kept horizontal when the front cover 12 is in the closing attitude. In other words, when the front cover 12 is the open attitude shaken by 90 deg. from the closing attitude, the imaginary operating line L tying a position where the press contact face 37 is in press contact onto the face 42 and the center of the shaft 15 is made coincident with the vertical line V.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tape cartridge characterized by a locking means for preventing rotation of a tape winding hub within a main body case when not in use.

[Conventional technology]

In a Beta system video cassette, a front cover 12 is swingably supported on the front surface of a main body case 1 about a pivot 15 via left and right connecting pieces 14 so that it can be opened and closed.

The opening of the hub 3 is linked to the upward opening movement of the front i12.

A method of releasing the lock is generally known. Also, in Japanese Utility Model Publication No. 53-2594, a method is known in which the hub lock means is unlocked in conjunction with the front FF112.

However, with this type of tape cartridge.

It is desirable to release the hub locking means after the player side drive shaft is securely engaged with the hub.

This is because if the lock is released before the drive shaft engages with the hub, there is a risk of tape sagging, which can lead to tape loading errors or the tape being damaged by the loading pin. .

However, these points are not taken into consideration in the prior art example described above.

For these reasons, the inventors of the present invention have developed the first tape cartridge for digital recording and playback method as shown in Figure 9.
As shown in Fig. 4, when the hub lock means is released in step i12, the release operation starts after the majority of the swinging stroke of the connecting piece 14 and is completed near the end of the swinging stroke. We investigated a prototype with the following settings.

There, a brake member 30 for preventing rotation of the hub 3 is mounted inside the main body case 1 so as to be slidable back and forth between a lock position at the rear and an unlock position at the front.
The operating arm 35 connected to the brake member 30 is guided out facing the front outer surface of the left and right side walls 16 of the main body case 1, and the front end of the operating arm 35 is biased backward by a spring member 31. A passive protrusion 36 is provided. Then, when the front cover 12 swings, for example, about 68 degrees from the closed position, the edge 14a of the connecting piece 14 comes into contact with the receiving surface 42 of the driven protrusion 36 and starts unlocking. It is set so that unlocking is completed when the connecting piece 14 swings to about 85 degrees as shown by the imaginary line.

This type of front lid 12 swings up to 90 degrees from the closed position.

[Problem that the invention seeks to solve]

If the lock release operation is performed in the area after the majority of the swing stroke of the connecting piece 14 in this way, there is a risk that the accumulated error will have a large effect on the release stroke of the brake member 30, leading to a situation where the lock cannot be released reliably. There is. In particular, as shown in FIG. 5, the brake member 30 is mounted inside the main body case 1 so as to be slidable back and forth, the brake member 30 is slidably biased to the rear lock position by the spring member 31, and the rear of the brake member 30 is In the configuration in which the elastic engagement pieces 36 provided on the left and right sides of the hubs 3 contact and engage with the portions 26 and 26 of the hubs 3 from the front to achieve hub locking, backlash at the pivot portion of the front lid 2,
Sliding play of the brake member 30.

When the looseness of each hub 3 on the drive shaft insertion hole 5 is added,
When the brake member 30 is slid forward to the unlocked position, one of the left and right hubs 3 may still remain in the one-handed locked state. In the comparative example shown in FIG. 14, a 5° swing range remains until the front cover 12 is completely opened after unlocking is completed, but even so, it is still insufficient to ensure a reliable unlocking operation. That was enough.

What can I do to resolve this kind of unlock failure? If the comparative example shown in FIG. 14 is examined in detail, it will be noticed that the position of the passive protrusion 36 at the start of unlocking is on the front side of the case from the perpendicular line 3 passing through the center of swing of the connecting piece 14. In this case, the only option is to move the passive protrusion 36 forward of the perpendicular line V while the brake member 30 is in the locked position. This is because, as the receiving surface 42 of the passive protrusion 36 moves away from the perpendicular line {circle over (2)}, the horizontal movement component of the passive protrusion 36 with respect to a constant swing angle of the front cover 12 naturally becomes larger.

However, in the form of the comparative example in which the end edge 14a of the front lid connecting piece 14 comes into contact with the receiving surface 42 of the passive projection 36.

Since there is a restriction that unlocking must be started at the rear of the majority of the swing area of the front cover 12, it is unreasonable to position the passive protrusion 36 at a large distance forward from the perpendicular line V. As will be described later, new problems arise, such as the member P that operates the front lid 12 to open upwardly coming into contact with and interfering with the passive protrusion 36. As described above, in the conventional configuration, there was no degree of freedom in design to obtain a release stroke, and there remained concerns about releasing the hub lock.

From this point of view, the present invention provides a method for moving the brake member 30 from the locking position to the forward unlocking position using the connecting piece 14 of the front cover 12 in conjunction with the upward swinging of the front cover 12. A part of the connecting piece 14 comes into contact with the receiving surface 42 of the passive protrusion 36 of the brake member 30 after the majority of the moving area, thereby retaining the advantage of delaying the start point of unlocking as the front cover 12 swings upward. do. Nevertheless, the object is to ensure a predetermined amount of movement stroke of the brake member 30 from the locked position to the unlocked position, and to make it possible to increase this movement stroke as necessary.

[Means to resolve the problem]

In order to achieve the above object, in the present invention, the lock is released in the area after the majority of the swing stroke of the connecting piece 14 in the front lid 12, and the receiving surface 42 of the passive protrusion 36 at the start of unlocking is connection piece 14 that comes into contact with
The positional relationship with the side contact surface 37 was determined as shown in FIG.

That is, the passive protrusion 36 connected to the brake member 30 is led out to the outer surface of the side wall of the main body case 1, and the contact surface 37 that comes into contact with the receiving surface 42 of the passive protrusion 36 is formed on the inner surface of the connecting piece 14 of the front lid 12. do. and.

When the brake member 30 is in the lock position, the receiving surface 42 is located on the rear side of the case with respect to the perpendicular line V passing through the center of the pivot shaft 15 of the connecting piece 14, and the receiving surface 42 is located in the majority part of the upward swinging area of the connecting piece 14. Thereafter, the contact surface 37 contacts the receiving surface 42, and the center of the pivot shaft 15 is defined as the position where the contact surface 37 contacts the receiving surface 42 when the front cover 12 is fully opened approximately 90 degrees from the closed position. The imaginary line of action connected thereto is located on the rear side of the case from the vicinity of the perpendicular line (2).

[Effect]

The front lid 12 is the ninth lid that closes the front of the case in a vertical position.
The closed position shown in the figure is changed to a position opened approximately 90° upward about the pivot shaft 15 as shown in Fig. 1O. In reality, after inserting and mounting the tape cartridge in a holder on the player side in a horizontal position, for example, when lowering the tape cartridge together with the holder to the loading position below, the member P on the player side comes into contact with the front lid 12. The front lid 12 swings upward.

At this time, after the majority of the top-opening swing area of the front lid 12, when the connecting piece 14 has swung, for example, about 68 degrees from the closed position, similar to the comparative example in FIG. The abutting surface 37 provided on the inner surface abuts the receiving surface 42 of the passive protrusion 36 as shown in FIG. 1, and unlocking begins. Then, just before the front cover 12 finishes opening completely, the hub lock release is completed in a posture in which the front cover 12 is swung by, for example, 85 degrees. S in the figure indicates the release stroke of the brake member 30 from the unlock start point to the unlock completion set point.

When the lock release completion point is set at the time when the front cover 12 swings 85 degrees as described above, the brake member 30 can be slid further forward until the front cover 12 is fully opened 90 degrees. This allows the accumulation errors of each part to be absorbed and unlocking to be performed more safely. Furthermore, when the front cover 12 is fully opened by approximately 90 degrees, the virtual line of action is located on the rear side of the case from the perpendicular line (2). In the example of FIG. 2, both lines L and ■ coincide.

In this way, the hub lock is released just before the tape cartridge held in the holder on the player side is set to the loading position, and at this stage, the drive shaft on the player side is already engaged with the hub 3 from below. In the fully set state, the front lid 12 is also fully opened to an upwardly open position of approximately 90 degrees.

〔Effect of the invention〕

According to the present invention as described above, the connecting piece 1 of the front cover 12
Connecting piece 141 after the majority of the upper opening swing area of 4
Since the abutment surface 37 of the Jt11 abuts against the abutment surface 42 of the passive protrusion 36 connected to the brake member 30, the release of the hub lock is completed after the player's drive shaft engages with the hub 3.

In addition, a contact surface 37 is formed on the inner surface of the connecting piece 14 of the front lid 12 instead of the edge 14a.

When the brake member 30 is in the locked position, the receiving surface 42 of the passive protrusion 36 can be positioned toward the rear of the case from the perpendicular line (3) with considerable design freedom. In other words, it becomes possible to move the receiving surface 42 far away from the perpendicular line (2). As a result, the amount of movement of the passive protrusion 36 (play half member 30) relative to a fixed swing angle of the connecting piece 14, that is, the release stroke S, can be increased, and the greatest advantage is that the hub 3 can be unlocked reliably. has. Receiving surface 4
The degree of contact of the contact surface 37 with respect to the brake member 2 can also be set to a level that does not cause strain or the like, and the movement of the brake member 30 can be performed smoothly.

Furthermore, with respect to the passive protrusion 36 led out to the outer surface of the case side wall 16, an abutting surface 37 to the receiving surface 42 is formed on the inner side of the front lid connecting piece 14 that swings on the outer side thereof. Therefore, unlike the configuration in which the end edge 14a of the connecting piece 14 comes into contact with the receiving surface 42 when the front lid 12 swings upward, the contact surface 37 contacts the receiving surface 42.
The contact action is ensured without causing a butting state. Also, from a two-functional perspective, as shown in FIGS.
Although it may be in a form in which the connecting piece 14 comes into contact with the receiving surface 42, in this case, the presence of the notch portion causes a decrease in the strength of the connecting piece 14, and the notch portion is dented, which is unsightly. Even when the tape end detection hole 41b is not in use, the tape end detection hole 41b (described later) is exposed, allowing dust to enter the case. However, it is also possible to change the shape of the front end of the side wall plate 19 of the shutter 18, which will be described later, to fill the notch when not in use, but this would make the side wall plate 19 too high. It becomes difficult to ensure the sliding properties of this material itself. Also.

When the front lid construction 2 adopts a form in which the end edge 14a of the connecting piece I4 is rested on the upper surface of the front end of the side wall plate 19 to lock the swinging of the front lid 12 in the upward opening direction when not in use, The connecting piece 14 and the side wall plate 19 become complicated in shape, and if they are made possible by force, problems arise in terms of strength. As described above, although the shutter 18 and the tape end detection means are not limited in specific implementation, there are various problems when the notch edge 14b is formed in the connecting piece 14. However.

According to the present invention, since the contact surface 37 is formed on the inner surface of the connecting piece 14, the above-mentioned problem does not occur.

〔Example〕

The drawing shows an example of an audio tape cartridge of a digital recording/playback type, and the overall configuration thereof will be explained.

In FIGS. 4 to 6, 1 is a main body case.

The main body case 1 is made of plastic upper and lower cases 1a and 1b.
are combined into a lid-like shape.

A hub 3 with tape 2 wrapped around the left and right inside of the main body case 1.
It has 3. These hubs 3, 3 are located above the left and right drive shaft insertion holes 5, 5 formed through the bottom wall 4 of the main body case 1, and are rotatable. The main body case 1 has tape guide members 6 on the front left and right sides. The tape 2 is led out from one hub 3 to the front of the case via these guide members 6, 6, and wound around the other hub 3.

The upper wall 7 of the main body case 1 has a transparent window 9 extending approximately between the left and right sides of the rear half. The amount of tape wrapped around each hub 3 can be visually confirmed through the transparent window 9.

A pocket 10 for tape loading is formed in the central front part of the main body case 1 in a recessed manner. The upper surface of this pocket 10 is closed by the case upper wall 7, but the front and lower surfaces are open.

A front cover 12 for protecting the tape is provided on the front of the main body case 1. This front lid 12 is a plastic molded product with a length that closes the front surface of the main body case 1 between the left and right sides, and connecting pieces 14, 14 are extended rearward from both left and right ends, and connecting pieces 14, 1
4, with pivot shafts 15, 15 protruding from the inner surface thereof in opposite directions. With the left and right connecting pieces 14 fitted onto the front ends of the left and right side walls 16 of the main body case 1, the pivots 15 are inserted into the transparent pivot holes on the case side (more specifically, the upper case la). The front lid 12 is then pivoted around the pivot shaft 15 between a posture in which the front surface of the main case 1 is closed and an upwardly opened posture, and is always biased to the closed posture by a spring member (not shown in Figure 1). has been done. If necessary, the pivot hole may be made into an elongated hole, into which the pivot shaft 15 is movably fitted, and the front cover 12 swings and rotates.

In FIG. 6, the main body case 1 has a shutter 18 that closes the bottom opening of the pocket 10 when not in use.

This shutter 18 has a flat plate shape along the case bottom wall 4, and has through holes 19 on the left and right sides of the center portion corresponding to the aforementioned drive shaft insertion holes 5.
・Side wall plate 20 having 19 and extending upwardly from the left and right ends
・20 is the case left and right side walls 16 and 1 as shown in Fig. 12.
6 in a locking manner, and the front end 18a closes the lower surface of the opening of the pocket 10 in a forward advancing position.

It is freely slidable back and forth, including a backward retracting position in which the lower surface of the cover (bokeh) 10 is completely opened.

The shutter 18 is urged to slide forward. As shown in FIG. 4, a spring member 25 is installed between the inner surface member 22 at the front part of the case bottom wall 4 and the spring receiver 23 provided on the inner surface of the front end of the shutter 18, as shown in FIG. The shutter 18 was urged to slide forward by the elastic force of the spring member 25.

Although the spring member 25 in the figure is a linear spring, the type and the way it is hooked can be changed as desired.

The main body case 1 is provided with a locking means for preventing the left and right hubs 3 from rotating when not in use. As this locking means, first, each hub 3 has a retaining part 26 having a smaller diameter above the main body part 3a around which the tape 2 is wound. The circular outer circumferential surface of the engaging portion 26 is made into a friction-retaining surface in which, for example, vertical engaging grooves are formed over the entire circumference.

In FIG. 7, a window 27 forming the transparent window 9 is opened in the upper wall 7 of the case. Plate 2 is attached to the inner surface of the case top wall 7.
Fix 9. The plate 29 is made of transparent plastic and has a window plate portion 29b at the rear of a main body plate portion 29a. The plate 29 is fixed to the case upper wall 7 with the transparent window plate part 29b fitting into the window 27, and a gap g is provided between the case upper wall 7 and the main body plate part 29a. A flat plate-like brake member 30 is positioned in front of both the hubs 3, 3 in this gap g, and is inserted and installed in a horizontal position so as to be slidable back and forth. Legs 30a are vertically disposed from the left and right ends of the brake member 30, and the lower end of each leg 30a is supported by being supported by the inner surface of the case bottom wall 4, and is guided and connected to the inner surfaces of the left and right side walls 16 of the case. I'll let you guess.

A spring member 31 that slides and urges the brake member 30 to the rear brake position between the brake member 30 and the case upper wall 7
Attach. Elastically deformable brake pieces 32 are integrally extended from the left and right rear ends of the brake member 30. Each brake piece 32 projects below the plate 29 through an opening 33 provided in the plate 29, and the tip of each brake piece 32 can abut and engage with the upper end retaining portion 26 of each hub 3.

In order to unlock the brake member 30 against the spring member 31, the operating arm 35 is extended to the front along the inner surfaces of the case left and right side walls 16, continuous with the one leg portion 30a.
Its front end is guided out of the case from the front side of the left and right side walls 16 of the case.

The passive protrusion 36 provided at the front end thereof is positioned at the rear of the majority of the swinging region of the connecting piece 14. Further, as shown in FIG. 3, the connecting piece 14 of the front lid 12 has an operating portion 37 formed in the shape of a projecting wall on the surface facing the case side wall 16, which abuts on the passive projection 36.

The passive protrusion 36 and the operating part 37 come into contact after the player's hub drive shaft is fully engaged with the hub 3 and the hub 3 is securely captured.

Set the position to start unlocking.

Next, the overall movement of each part will be explained. When the tape cartridge is not in use, the front FF 112 is held in a closed position and covers the outside of the front surface of the tape 2. The shutter 18 is slid toward the front edge by a spring member 25, and the fifth
The front end 18 of the shutter 18 as shown in FIG.
a closes the lower surface of the pocket 1O, and the drive shaft insertion holes 5 provided in the case bottom wall 4 are also closed. The upper surfaces of the front ends of the left and right side wall plates I9 and 19 of the shutter 18 are the lower edges 14 of the left and right connecting pieces 14 and 14 of the front lid 12 in the closed position.
a.14a, and this locks the front cover 12 from swinging. Brake member 30
is slid backward by a spring member 31, and each brake piece 3
2 abuts and engages with the upper end engaging portion 26 of each hub 3, and each hub 3
We are trying to stop the rotation.

When a tape cartridge is inserted into a holder on the player side from the front side of the case in a horizontal position, for example, the shutter 18 is first slid rearward against the spring member 25 on the player side, as shown in FIG. in pocket 1
0 is in an open state, and the through holes 19 provided in the shutter 18 are aligned with the drive shaft insertion holes 5, 5, and the drive shaft is in an open state allowing insertion of the drive shaft. Next, when the tape cartridge loaded in the holder is lowered to the loading position, a member on the player side comes into contact with a part of the front lid 12, and the front lid 12 is rotated to open upward.

In parallel with this, the tape loading pin on the player side enters the pocket 10, and the drive shaft enters each hub 3 from below. After the drive shaft is fully fitted into each hub 3,
The brakes of each hub 3 are released in conjunction with the upward rotation of the front cover 12. Namely.

The connecting piece 14 that has rotated from above comes into contact with the passive protrusion 36 of the brake member 30, and this causes the brake member 30 to slide toward the front of the case against the spring member 31, and each brake piece 32 is removed from the engaging portion 26 of each hub 3.

Incidentally, the shutter 18 is locked in sliding at the forward sliding position where the lower surface of the pocket 10 is closed and at the rear sliding position where the lower surface of the pocket 1-10 is opened. As the locking means, lock holes 39 and 40 are formed in the left side of the figure in the figure, and lock pieces 38 that selectively engage with the lock holes 39 and 40 are provided on the case bottom wall 4 side in the vertical direction. It is integrally formed so that it can be elastically deformed. This unlocking is performed by bringing a member on the player side into contact with the locking piece 38.

Note that there are detection holes 41a and 41b at the top and bottom of the front ends of the left and right side walls 16 and 16 of the main body case 1 for detecting the end of the tape.
are formed through each.

Prisms 41c are installed on the left and right sides of the front end inside the main body case 1, and the detection light from the player side is projected into the case from, for example, the lower detection hole 41a, and is emitted outside the case from the lower detection hole 41b via the prism 41c. The light is received by a sensor on the player side. When not in use, these detection holes 41a and 41b are closed by the left and right connecting pieces 14, respectively, and are opened when the front lid 12 is in the upwardly open position. This tape end detection means is just one example.

There is a hole in the center of the front end of the bottom wall 4 of the main body case 1, into which a lamp on the player side enters, and the light from this lamp is received by a sensor on the player side through detection holes provided on the left and right side walls 16 of the case. It may be something that is done.

Basically, in the tape cartridge having the above structure, two parts of the present invention are the front cover 1? It is characterized in that the arrangement relationship between the connecting piece 14 and the passive protrusion 36 connected to the brake member 30 is set as shown in FIG. 1, so that lock release can be performed reliably. Next, an example regarding this point will be described.

[Embodiment 1] FIGS. 1 to 3 show a first embodiment of the present invention, in which the inner surface of each connecting piece 14 of the front cover 12 is A contact surface 37 that comes into contact with the receiving surface 42 of the passive protrusion 36 is formed. The receiving surface 42 is located on the rear side of the case from the perpendicular line (3) passing through the center of the pivot shaft 15 of the connecting piece 14. Thus, lol
Connecting piece 1 when the JAiIJ axis sufficiently captures the hub 3
At the swing position 4 (68 degrees swing from the closed position),
It is set so that the contact surface 37 contacts the receiving surface 42 and unlocking is started. Furthermore, the imaginary line of action connecting the contact surface 37 and the center of the pivot shaft 15 is made horizontal when the front lid 12 is in the closed position. In other words, when the front cover 12 is in the open position, which is swung 90" from the closed position, the contact surface 37
The imaginary line of action connecting the center of the pivot shaft 15 and the point where the bearing surface 42 comes into contact with the receiving surface 42 is set to coincide with the perpendicular line V.

When this is done, the passive protrusion 36 can be moved away from the perpendicular line ■ to the rear of the case as much as necessary, so as shown in Fig. 2 (
It is possible to take a large release stroke S from the lock release start point to the lock release completion set point immediately before the front lid 12 completely opens (a position 85 degrees from the closed position). The member P on the player side is set to contact the protruding base end of the connecting piece 14 of the front lid 12 from below, but in that case, when the member P pushes up the front lid 12 and operates to open it. Since the outer side of the passive protrusion 36 is completely covered by the connecting piece 14 and is located sufficiently away from the front end of the side wall 16 of the main body case 1, the member P and the passive protrusion 36 abut and interfere with each other. Never.

[Example 2] FIG. 13 shows a second embodiment of the invention.

In this case, the case side wall 16 is connected to the connecting piece 14 of the front cover 12.
The contact surface 37 was formed by recessing the inner surface facing the contact surface 37. The rest is substantially the same as the above embodiment.

[Another example]

Although the illustrated example is as described above, the present invention is not limited thereto. For example, when the front lid 12 is in the open position, which is swung 90 degrees from the closed position, the virtual line of action that connects the contact point between the contact surface 37 and the receiving surface 42 and the center of the pivot axis I5 is in the vicinity of the perpendicular line V. It would be better if it was closer to the rear of the case.

In each of the embodiments described above, the passive protrusion 36 is formed into a wedge shape, but the receiving surface 42 thereof may be formed into an arc surface if necessary. Similarly, the operating portion 37 that abuts the receiving surface 42 of the abutting surface 37 may also be formed into an arcuate surface. The passive protrusion 36 may be provided on either the left or right side of the brake member 30 depending on the case.

Furthermore, it goes without saying that the brake members 30 that come into contact with each hub 3 can also be modified into various forms.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, and FIG. 1 is a side view of the main parts in the unlocking start state;
FIG. 2 is a side view of the main parts in the unlocked state, and FIG. 3 is a sectional view taken along the line D in FIG. 2. Figures 4 to 12 illustrate the tape cartridge to which the present invention is applied, with Figure 4 being an external perspective view, Figure 5 being a plan view of the internal structure, and Figure 6 showing the bottom shape of the main body case. FIG. 7 is an exploded perspective view showing the upper case and plate brake member constituting the main body case, FIG. 8 is a perspective view of the main parts showing the unlocked state, Figure 9 is a sectional view taken along the line A-A in Figure 5, Figure 10 is a vertical side view corresponding to Figure 9 with the front lid open, and Figure 11 is a sectional view taken along the line B-B in Figure 5. , FIG. 12 is a sectional view taken along the line CC in FIG. 5. FIG. 13 is a side view of essential parts showing a second embodiment of the present invention. FIG. 14 is a side view of main parts showing a comparative example. 15(a) and 15(b) are side views of the main parts of a comparative example, respectively. FIG. 15(a) is a state where the front lid is in a closed position, and FIG. 15(bl is a state where the front lid is in an open position. ■...Body case. 2...Tape. 3...Hub. 12...Front cover. 14...Front cover connecting piece. 15...Front Pivot of the lid. 30... Brake member. 31... Spring member. 36... Passive protrusion. 37... Contact surface. 42... Receiving surface. ■... Perpendicular line. L...・Virtual line of action.

Claims (1)

[Claims] A brake member 30 for preventing rotation of the hub 3 is placed in the main body case 1 housing the hub 3 around which the tape 2 is wound, and has two positions: a locking position at the rear where the brake member 30 is brought into contact with the hub 3, and a unlocking position at the front where the brake member 30 is disengaged from the hub 3. A front cover 12 that closes the front side of the front cover to the main body case 1 is pivotally supported around a pivot 15 through left and right connecting pieces 14 so that it can be opened and closed. In the tape cartridge in which the brake member 30 is moved to the unlock position by the upward swinging of the connecting piece 14, a passive protrusion 36 connected to the brake member 30 is led out to the outer surface of the side wall of the main body case 1,
A contact surface 37 is formed on the inner surface of the connecting piece 14 of the front lid 12 to contact the receiving surface 42 of the passive protrusion 36, and when the brake member 30 is in the lock position, the receiving surface 4
2 is located on the rear side of the case with respect to the perpendicular line V passing through the center of the pivot shaft 15 of the connecting piece 14, and the contact surface 37 contacts the receiving surface 42 after the majority of the top-opening swing area of the connecting piece 14,
The location where the contact surface 37 contacts the receiving surface 42 when the front lid 12 is fully opened approximately 90 degrees from the closed position and the pivot 1
5. A tape cartridge characterized in that an imaginary line of action L that connects the center of the tape cartridge 5 is located on the rear side of the case from the vicinity of the perpendicular line V.