JP3082338B2 - Tape cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel tape cassette. More specifically, in a tape cassette provided with a front lid that covers the front side of the magnetic tape, the space required for rotating the lid and opening the lid can be reduced by devising the fulcrum structure of the front lid. It is another object of the present invention to smoothly rotate the lid.

[0002]

2. Description of the Related Art With the recent increase in recording density, magnetic tapes have become increasingly disliked by dust, and a front lid for covering the front surface of the magnetic tape has been provided so that the magnetic tape is not exposed when not in use. It is.

FIGS. 10 to 12 show an example a of such a conventional tape cassette.

[0004] Reference numeral b denotes a cassette case, which has a flat box shape that is oblong and rectangular when viewed from above. Two tape reels (not shown) are rotatably accommodated in the cassette case b, and a part of the magnetic tape c having both ends fixed to the two tape reels respectively is a cassette case b.
Are drawn out of the cassette case b from unillustrated tape outlets formed at both left and right ends of the front surface of the cassette case b and are located along the front surface of the cassette case b.

[0005] Reference numeral d denotes a mouth portion formed between two tape outlets on the front surface of the cassette case b and opened forward and vertically.

Reference numeral e denotes a front lid for opening and closing the front surface of the cassette case b. The front lid f corresponds to the front surface of the cassette case b, an upper surface portion g projecting rearward from the upper edge of the front surface portion f, and a front portion. Side portions h, h (only one is shown in the drawing) projecting rearward from both left and right ends of f are integrally formed, and pin portions i, i projecting from the side portions h, h are formed. (Only one of them is shown in the drawings.) Is rotatably supported by support holes formed in the left and right side surfaces of the front end of the cassette case b.

The front lid e is closed by a spring (not shown), that is, as shown in FIG. 10, the front face f is located at the front side of the portion of the magnetic tape c located outside the cassette case b. That is, the turning power is biased toward the lid closing position.

Further, at positions slightly inward from the left and right sides of the upper surface portion g of the front lid e, that is, at portions corresponding to both ends of the mouse portion, support pieces j, j (one of which is shown in FIG. Only shown).

Reference numeral k denotes a back lid which covers the back surface of the magnetic tape c in the mouse portion d. The shafts l and l (only one of them is shown in the drawing) are approximately at the center of the left and right end surfaces in the vertical direction. The shafts l, l are rotatably supported by the lower ends of the support pieces j, j of the front lid e.

Guide pins m, m (only one of them is shown in the drawing) project from the lower ends of the left and right ends of the back lid k, and the guide pins m, m are cassette cases. Guide pins m, m of the back lid k are slidably engaged in guide grooves n, n (only one of them is shown in the drawing) formed on both left and right sides of the mouth portion d of b. I have.

An upper lid o extending horizontally is integrally formed at the upper end of the back lid k.

FIG. 10 shows that the front lid e and the back lid k cover the portion where the front lid f is located outside the cassette case b of the magnetic tape c from the front side. Is located at the position covering the magnetic tape c from the rear side in the mouse part d. In this state, the front half of the upper end of the mouse part d is formed by the upper surface part g of the front lid e, and the rear half is formed by the upper lid o. , Each is covered.

When the entire upper end of the mouse d is covered by the upper surface of the front lid, the pivot point of the front lid is one point, and the front lid is positioned above the back lid when the lid is opened. Therefore, the amount of protrusion of the front lid upward when the lid is opened is too large. Therefore, a portion covering the upper end of the mouse d is divided into an upper surface portion g of the front lid e and an upper lid o, and the upper lid o is located rearward of the upper surface portion g of the front lid e when the lid is opened. The upward projection of the lid e is prevented from increasing.

When the tape cassette a is held by a cassette holder (not shown) and lowered toward the cassette mounting portion of the video tape recorder, first,
A lid opener p provided on the video tape recorder contacts the lower edge of one side surface h of the front lid e (see FIG. 10).

When the cassette holder further descends, the lid opener p relatively rises, so that the front lid e is opened against the turning force toward the closed position biased by the front lid e. It is rotated toward the lid position (see FIG. 11), and finally reaches the lid opening position shown in FIG. During this time, the back lid k moves its posture toward the opening position while being controlled by the rotation fulcrum (axis l, l) and the change in the position of the guided pins m, m guided by the guide grooves n, n. To reach the lid opening position at the same time as the front lid e reaches the lid opening position.

[0016]

In the above-mentioned tape cassette a, since the fulcrum structure of the front lid e is a single fulcrum, the space required for the opening operation and the upward movement of the opening position are required. The protrusion amount becomes large.

In particular, if an upper surface portion for closing the upper opening of the mouth portion d is provided on the front lid, the upward projection amount when the lid is opened becomes extremely large.
The front lid e is provided with only an upper surface portion g that covers substantially the front half of the upper opening of the mouse portion d, and the rear half is covered with an upper lid o provided on the back lid k. Is not too large.

As a result, there are problems that the structure becomes complicated and the strength of the front lid decreases.

[0019]

In order to solve the above-mentioned problems, the tape cassette of the present invention comprises a magnetic tape having both ends secured to a tape reel rotatably housed in a cassette case. Mouth portions that are led out from the tape outlets at both ends of the front surface of the cassette case and are positioned along the front surface of the cassette case and that are opened forward and vertically at the portion between the two tape outlets in the front surface portion of the cassette case A front lid that opens and closes the front of the cassette case is rotatably supported at the front end of the cassette case,
The front lid is integrally formed with a front portion that covers the front surface of the cassette case and side portions protruding rearward from left and right side edges of the front portion, and the two side portions of the front lid have different positions from each other. Two fulcrum pins and two arc grooves respectively guiding the two fulcrum pins are rotatably supported by the cassette case, and each of the two arc grooves is formed in an arc shape centered on one end of the other groove. A lid return spring for urging the front lid to rotate in a direction to close the front surface of the cassette case is inserted between the one side surface of the front lid and the cassette case, and the lid return spring is not inserted. The width of one of the arc grooves connecting the side of the side and the cassette case is compared with that of the side where the lid return spring is inserted, and the other arc forms a pair. Wider formed farther from, during rotation of the front lid the two pivot pins are above 2
The two arc grooves are sequentially moved.

[0020]

Therefore, in the tape cassette of the present invention, the front lid is rotated by the two fulcrum pins and the two arc grooves so that the two fulcrum pins sequentially move in the two arc grooves when the front lid is rotated. Since the front lid is supported by the cassette case, the front lid can be prevented from greatly projecting above the cassette case when the lid is opened.

In addition, the turning force of the lid return spring is applied to only one side of the front lid, and the front lid is twisted, and the fulcrum pin cuts into the edge of the arc groove on the other side and cannot move. However, in the tape cassette of the present invention, one of the arc grooves on the other side is formed wide, so that even if the front lid is twisted, the fulcrum pin is located at the edge of the arc groove. Engagement can be avoided, thereby ensuring smooth rotation of the front lid.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the tape cassette of the present invention will be described below with reference to the first embodiment shown in the accompanying drawings. In the illustrated embodiment, the present invention is applied to a tape cassette for 8 mm video.

Reference numeral 2 denotes a cassette case, which is formed in a flat box shape having a horizontally-long rectangular shape when viewed from above, and in which two tape reels 3, 3 are rotatably housed. Both ends of the magnetic tape 4 are fixed to and wound around the reels 3, 3, respectively.

Tape outlets 5 and 5 are formed at both left and right ends of the front surface of the cassette case 2, and guides 6 and 6 in the cassette are integrally formed at ends of the tape outlets 5 and 5 which are closer to each other. ing.

A part of the magnetic tape 4 is connected to the tape outlet 5,
5 is drawn out of the cassette case 2, and both ends of the drawn-out portion are positioned along the front surface of the cassette case 2 in a state of being wound around the guides 6 in the cassette.

Reference numeral 7 denotes a mouth portion formed between the tape outlets 5 in the front portion of the cassette case 2, and is open to the front and up and down.

At the front ends of the side walls 8, 8 of the cassette case 2, arc grooves 9, 10, and 9 ', 10' are formed. The lower circular arc grooves 9, 9 'are formed in a slightly upward direction, and the upper circular grooves 10, 10' are formed in a direction in which the upper end is displaced slightly rearward from the upright posture. The front ends 9a, 9'a of 9, 9 'are circular arc grooves 10, 10'.
Are located substantially directly below the rear ends 10b, 10'b, and the rear ends 9b, 9'b of the arc-shaped grooves 9, 9 'are substantially immediately behind the front ends 10a, 10'a of the arc-shaped grooves 10, 10'. positioned.

Also, the arc grooves 10, 10 'are formed in the arc grooves 9, 9 respectively.
′ Are formed in an arc shape centered on the rear end portions 9b and 9′b, and the arc grooves 9 and 9 ′ are formed on the rear end portions 10 of the arc grooves 10 and 10 ′.
b and 10'b.

Further, the lower edge 9'c of the lower arc groove 9 'on one side is smaller than the lower edge 9c of the arc groove 9 on the opposite side.
Displaced downwardly toward 'a, so that the width of the arc-shaped groove 9' becomes wider toward the front end.

Numeral 11 denotes a spring hooking portion projecting slightly behind and slightly above the rear end 9b of the lower arc groove 9 of the side surface of the cassette case 2.

Reference numerals 12 and 12 denote guide grooves formed on both right and left sides of the mouse portion 7 so as to extend substantially vertically.
The portion near the upper end has a substantially “U” shape slightly rearward.

A front lid 13 covers the front of the cassette case 2, an upper surface 15 protruding rearward from an upper edge of the front portion 14 and covering the upper end opening of the mouse portion 7, and a front portion 14 Side portions 16, 16 projecting rearward from the left and right side edges of the upper surface portion and having an upper edge continuous with the side edge of the upper surface portion 15.
And 'are integrally formed.

Two fulcrum pins 17, 18 and 17 ', 18' are provided on the inner surfaces of the side surfaces 16 and 16 ', respectively. And these fulcrum pins 17, 17 'and 1
8 and 18 ', the distance between the arc grooves 9, 9' and 1
The radius of curvature of 0, 10 ', that is, the interval from the rear ends 9b, 9'b of the arc grooves 9, 9' to the respective portions of the arc grooves 10, 10 'and the rear ends 10b of the arc grooves 10, 10', The distance from 10'b to each part of the arc grooves 9, 9 'is the same.

Reference numeral 19 denotes a fulcrum pin 1 of the inner surface of the side surface portion 16.
7 is a spring hook portion protruding at a position slightly behind the lower part of FIG.

The fulcrum pins 17 and 17 'are separately provided in the lower arc grooves 9 and 9', respectively, and the fulcrum pins 18 and 18 'are provided.
Are separately slidably engaged with the upper arc grooves 10, 10 ', whereby the front lid 13 is rotatably supported by the front end of the cassette case 2.

Numeral 20 denotes a lid return spring, which is formed by bending a linear spring material into a circular shape.
a and 20b project in the radial direction, and the upper supported piece 20
a is supported so as to elastically contact the spring hooking portion 11 of the cassette case 2 from above, and the lower supported piece 20b is supported so as to elastically contact the spring hooking portion 19 of the front lid 13 from below. Thus, the lid return spring 20
Is mounted between the cassette case 2 and the front lid 13 in a state where the elastic force in the direction in which the ring is opened is stored, and in a state where the ring surrounds the fulcrum pins 17 and 18.

In this manner, the resiliency of the lid return spring 20 acts to move the fulcrum pins 17 and 18 substantially along the arc grooves 9 and 10.

Therefore, when the front lid 13 is in the closed position shown in FIG. 4, the resilience of the lid return spring 20 causes the fulcrum pin 17 to move to the rear end 9b of the arc groove 9 and the fulcrum pin 18 to move. Acts on the front end 10a of the arc groove 10, whereby the front lid 13 is held in the closed position.

While the tape cassette 1 is held by a cassette holder (not shown) of the video tape recorder and is lowered toward the cassette mounting portion, the lid opener 21 provided on the video tape recorder is operated by the front lid 13. When the lid opener 21 relatively presses the lower edge of the side portion 16 upward, the front lid 13 is provided with a turning power upward.

In the closed position, the fulcrum pins 17 and 17 'of the front lid 13 are located at the rear ends 9b and 9'b of the circular arc grooves 9 and 9', and the fulcrum pins 18 and 18 'are circular arc grooves 10 and 9'. Since it is located at the front end 10a, 10'a of 10 ', only the fulcrum pins 18, 18' are circular arc grooves 10, 10 '.
First, the fulcrum pins 18 and 18 ′ are moved in the arc grooves 10 and 10 ′, respectively.
The fulcrum pins 17, 17 'at the rear end 9b, 9'b of 9'
Arc groove 10, 10 'on the arc centered on the rear end 10
b, 10'b.

Then, the fulcrum pins 18 and 18 ′ are
When it reaches the rear end portions 10b and 10'b of 0, 10 '(FIG. 5
), And the fulcrum pins 17 and 17 'are now in the circular arc grooves 9 and 9'.
Fulcrum pin 1
7, 17 'extend in the circular arc grooves 9, 9' in the circular arcs around the fulcrum pins 18, 18 'at the rear ends 10b, 10'b of the circular arc grooves 10, 10'. Front end 9a, 9 '
Move toward a.

The position where the fulcrum pins 17 and 17 'reach the front ends 9a and 9'a of the arc grooves 9 and 9' is the open position of the front lid 13 (see FIG. 6).

As described above, the front lid 13 pivots about the fulcrum pins 17 and 17 'until it reaches a position halfway toward the opening position, and thereafter pivots about the fulcrum pins 18 and 18'. The amount of protrusion from the upper surface of the cassette case 2 at the open position can be reduced.

In this open position, the fulcrum pins 17 and 17 ′ are moved to the front lid 13 by the lid return spring 20 so that the fulcrum pins 17 and 17 ′ pass through the arc-shaped grooves 9 and 9 ′ at the rear end 9.
The turning power in the direction of moving toward b, 9'b is urged. In this state, the fulcrum pins 18 and 18 'cannot move in the circular arc grooves 10 and 10', but the fulcrum pins 17 and 17 'move in the circular arc grooves 9 and 9'. Can be done.

When the tape cassette 1 is moved upward from the cassette mounting portion of the video tape recorder, the lid opener 21 relatively escapes downward, so that the front lid 13 is provided by the lid return spring 20. The cover is rotated toward the closed position by the rotating force.

That is, first, the fulcrum pins 17, 17 ′ move inside the arc grooves 9, 9 ′ at the rear ends 10 b, 1 ′ of the arc grooves 10, 10 ′.
It moves toward the rear ends 9b, 9'b of the arc grooves 9, 9 'on an arc centered on the fulcrum pins 18, 18' at 0'b.

At this time, since the lid return spring 20 is erected only on one side,
The resilience of the lid return spring 20 is applied to the fulcrum pin 17 in the circular groove 9.
In the rear end portion 9b, but only a rotational force acts on the side surface portion 16 '. Should the torsion occur in the lid 13 and the fulcrum pin 18 'moves toward the front end 10'a of the arc groove 10', the fulcrum pin 17 'turns to the arc of the arc groove 9'.
The trajectories do not match, and the fulcrum pins 17 'and 18' are stretched so as to bite into the edges of the arc grooves 9 'and 10' on the far side, and the fulcrum pins 17 'and 18' cannot move. By the front lid 13
May not be able to move to the closed position.

However, in the tape cassette 1, as described above, the arc groove 9 'is formed slightly wider on the lower edge 9'c side, so that the fulcrum pin 17' is connected to the arc groove 9 '. Without sticking to the edge of ´
The front lid 13 can rotate toward the closed position.

When the fulcrum pins 17, 17 'reach the rear ends 9b, 9'b of the arc grooves 9, 9', the fulcrum pins 1
8, 18 'are formed in the arc grooves 10, 10' in arcs around the fulcrum pins 17, 17 'at the rear ends 9b, 9'b of the arc grooves 9, 9'. Front end 10a, 1
Move toward 0'a.

Then, the fulcrum pins 18 and 18 'are
The position where the front ends 10a and 10'a of the front lids 0 and 10 'are reached is the closed position of the front lid 13.

On the lower surface of the upper surface portion 15 of the front lid 13, a rear surface portion 22 suspended in the mouth portion 7 is integrally formed. The back portion 22 has a length corresponding to the mouse portion 7.
It has a plate shape that is almost the same as the length. Supporting pieces 23, 23 protruding rearward and downward are integrally provided at both left and right ends of the back face, and support pins 23a protruding toward each other are provided on opposing surfaces of the supporting pieces 23, 23. , 23
a is protrudingly provided.

As described above, since the front lid 13 is formed in a substantially U-shaped groove shape by the front surface portion 14, the upper surface portion 15, and the rear surface portion 22, the overall rigidity is increased, and even if the front lid 13 is pressed with a somewhat strong force. There is no bending.

Reference numeral 24 denotes a back lid having a narrow plate shape, and the length thereof is formed to be substantially the same as the length of the mouse unit 7 in the left-right direction. Notches 25, 25 are formed at the left and right ends of the upper end of the back lid 24.
Receiving portions 26, 26 protruding substantially upward and rearward are protrudingly provided at the ends closer to each other, and receiving holes 26a, 26a are formed in the receiving portions 26, 26.

Projections 27, 27 project rearward from both ends of the back lid 24.
Guide pins 2 protruding on opposite sides of each other
7a and 27a are protrudingly provided.

The receiving portion 2 of the back lid 24
The front lid 13 is inserted into the receiving holes 26a, 26a.
Of the front lid 13 is rotatably connected to the lower end of the rear portion 22 of the front lid 13.
Is substantially in contact with the upper end of the back lid 24.

The guided pin 27 of the back lid 24
a, 27a are slidably engaged with guide grooves 12, 12 formed on both side surfaces of the mouth portion 7 of the cassette case 2.

With the front lid 13 in the closed position, the front portion covers the front side of the portion of the magnetic tape 4 exposed outside the cassette case 2, and the rear portion 22
Covers most of the back side of the magnetic tape 4 in the mouse 7, and the lower end of the back lid 24 is in contact with the back side of the front part 14 of the front lid 13, and the lower end of the back side of the magnetic tape 4 in the mouse 7 And the lower portion of the magnetic tape 4.

While the front lid 13 moves toward the opening position as described above, the back lid 2
4 indicates that the guided pins 27a, 27a
The posture is controlled by being guided by the guide grooves 12, 12 so that the magnetic tape 4 does not come into contact with the posture.

[0059]

As is apparent from the above description, the tape cassette of the present invention has a magnetic tape whose both ends are fixed to a tape reel rotatably housed in a cassette case. A mouth portion is formed along the front surface of the cassette case, which is led out from the tape outlets at both ends of the front surface, and is formed with a mouth portion opened forward and vertically in a portion between the two tape outlets in the front portion of the cassette case. A front lid for opening and closing the front of the cassette case is rotatably supported at the front end of the case. The front lid covers a front of the cassette case, and side portions protruding rearward from right and left side edges of the front. Are formed integrally, and the two side portions of the front lid guide the two fulcrum pins and the two fulcrum pins which are different from each other. The two arc-shaped grooves are rotatably supported by the cassette case. The two arc-shaped grooves are each formed in an arc shape centered on one end of the other groove, and are formed between one side surface of the front lid and the cassette case. Insert the lid return spring between the front lid and the front lid that urges the turning power in the direction to close the front of the cassette case, and connect the side of the side where the lid return spring is not inserted with the cassette case. The width of one of the arc grooves is larger than that of the other side where the lid return spring is inserted, and is formed to be wider on the side farther from the other arc groove. The present invention is characterized in that one fulcrum pin sequentially moves through the two arc grooves.

Therefore, in the tape cassette of the present invention, the front lid is rotated by the two fulcrum pins and the two arc grooves so that the two fulcrum pins sequentially move in the two arc grooves when the front lid is rotated. Since the front lid is supported by the cassette case, the front lid can be prevented from greatly projecting above the cassette case when the lid is opened.

Further, the turning force by the lid return spring is applied only to one side of the front lid, and the front lid is twisted, and the fulcrum pin cuts into the edge of the circular arc groove on the other side and cannot move. However, in the tape cassette of the present invention, one of the arc grooves on the other side is formed wide, so that even if the front lid is twisted, the fulcrum pin is located at the edge of the arc groove. Engagement can be avoided, thereby ensuring smooth rotation of the front lid.

It should be noted that the specific shapes and structures shown in the above embodiments are merely examples for embodying the present invention, and the technical scope of the present invention is limitedly interpreted. It is not what is done. In particular, in the above embodiment, the fulcrum pin is formed on the front lid and the arc groove is formed on the cassette case. However, an arc groove may be formed on the front lid and the fulcrum pin may be formed on the cassette case.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of a tape cassette of the present invention.

FIG. 2 is a perspective view.

FIG. 3 is a horizontal sectional view.

FIG. 4 is a side view showing the lid opening operation together with FIG. 5 and FIG. 6, and showing an initial state with a part cut away.

FIG. 5 is a side view showing a state in the middle of the lid opening operation with a part cut away.

FIG. 6 is a side view showing a state where the lid has reached a lid opening position, with a part thereof being cut away.

FIG. 7 is an enlarged side view of a main part of the cassette case showing details of an arc groove;

FIG. 8 is an exploded perspective view showing main parts of a front lid and a back lid in an exploded manner.

FIG. 9 is an enlarged perspective view showing an arc groove forming portion of the cassette case.

FIG. 10 is a sectional view of a main part showing an example of a conventional tape cassette in a closed state.

FIG. 11 is a cross-sectional view showing an example of a conventional tape cassette in a state in the middle of a cover opening operation.

FIG. 12 is a cross-sectional view showing an example of a conventional tape cassette in an open state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tape cassette 2 Cassette case 3 Tape reel 4 Magnetic tape 5 Tape exit 7 Mouse part 9, 9 'Arc groove 9' Widened arc groove 10, 10 'Arc groove 13 Front lid 14 Front part 16, 16' Side part 17, 17 'fulcrum pin 18, 18' fulcrum pin 20 lid return spring

Claims (1)

(57) [Claims] 1. A part of a magnetic tape having both ends fastened to a tape reel rotatably housed in a cassette case is led out from tape outlets at both ends of a front surface of the cassette case and extends along the front surface of the cassette case. A mouth part is formed between the two tape outlets in the front part of the cassette case and is opened forward and vertically, and a front lid for opening and closing the front of the cassette case is rotated at the front end of the cassette case. Freely supported, the front lid is formed by integrally forming a front portion covering the front surface of the cassette case and side portions protruding rearward from left and right side edges of the front portion,
The two side portions of the front lid are rotatably supported by the cassette case by two fulcrum pins at different positions and two arc grooves for guiding the two fulcrum pins separately. The two arc grooves are respectively A lid return formed in an arc shape with one end of the other groove as a center, and for urging the front lid between the one side part of the front lid and the cassette case in a direction to close the front surface of the cassette case to the front lid. Insert the spring and change the width of one of the arc grooves connecting the side of the side where the lid return spring is not inserted and the cassette case to the side where the lid return spring is inserted. The front lid is formed wider on the side farther from the other pair of arc grooves, and the two fulcrum pins sequentially move through the two arc grooves when the front lid rotates. Tape cassette according to claim.