JP2827421B2 - Magnetic tape cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The magnetic tape cassette of the present invention will be described in detail according to the following items.

A. Industrial application fields B. Summary of the invention C. Prior art D. Problems to be solved by the invention [FIG. 7] E. Means for solving the problems F. Embodiments [FIGS. 1 to 6] Figures] a. Cassette case [Figs. 1 to 5] b. Front lid [Figs. 1 to 6] c. Rear lid [Figs. 1, 3 to 6] d. Guide groove [ FIGS. 1, 3 to 5] e. Defining the closing position of the rear cover and covering the magnetic tape [1.
Figure (A)] f. Locking of the rear lid and front lid [Fig. 1] g. Opening lid [Fig. 1 (B), Fig. 1 (C)] h. Stopper projection [Fig. 1, Fig. 3 Figures to FIG. 5] G. Effects of the Invention (A. Industrial Application Field) The present invention relates to a novel magnetic tape cassette. Specifically, in a magnetic tape cassette in which the magnetic tape is protected not only by the front lid when not in use but by the front lid and the rear lid so as to surround the magnetic tape from the front and rear, a small force is applied to the front lid. It is an object of the present invention to provide a novel magnetic tape cassette in which the front lid is not deformed at the position where the magnetic tape cassette is placed.

(B. Summary of the Invention) The magnetic tape cassette of the present invention has a front cover which is open at least on the front and lower surfaces of the cassette case and has a rear cover located therein. A stopper projection is provided in contact with the surface portion, whereby when the front lid is likely to be deformed rearward by receiving a force from the outside, particularly from the front, the stopper projection is provided on the rear surface of the front lid. Abuts and prevents rear deformation of the front lid,
The strength of the front lid is improved.

(C. Prior Art) In a tape cassette using a recording medium tape, for example, a magnetic tape, a front cover for protecting the tape wrapped along the front surface of the cassette case from contact with dust and fingers. Is rotatably provided on the cassette case so as to be moved between a closed position for covering the front surface and an open position for opening the front surface.

Such a front lid includes a main portion that covers the front surface of the cassette case, and supported portions protruding from both left and right ends of the portion, and the supported portion is rotatably mounted on the left and right side walls of the cassette case. Many have supported it.

In addition, since the magnetic tape with the increased recording density needs to particularly avoid contact with dust and fingers, a rear lid is provided in addition to the front lid, and when not in use, the magnetic tape is moved back and forth by the front and rear lids. There has been proposed a magnetic tape cassette which is surrounded by and protected from, for example, one disclosed in Japanese Patent Application No. 1-289670.

(D. Problems to be Solved by the Invention) [FIG. 7] In the above-described conventional magnetic tape cassette, both ends of the front cover are rotatably supported by the cassette case. The parts are not specifically supported.
Therefore, there is a problem that it is weak against external force.

As shown in FIG. 7, the above-described magnetic tape cassette a
In this configuration, the guided pin c of the rear lid b is pressed against the front side face f of the initial guide portion e of the guide groove d by the elastic force of the torsion spring g, so that the rear lid b is locked in the closed position. The front lid h is locked by locking the rear lid b in this manner, but when the central portion of the front lid h, that is, the portion corresponding to the concave portion i is pushed from the front as shown by the arrow j. The central portion of the front lid h bends rearward and is pushed by the rear lid b to rotate rearward, so that the guided pin c moves rearward from the initial guide portion e of the guide groove d. (The state shown by the two-dot chain line in FIG. 7), the lock is released, and the front lid h and the rear lid b open.

Therefore, the front lid h is strongly pushed from the front with fingers or the like,
There is a problem that the lock is released and the magnetic tape k is exposed when an impact is applied to the front lid h due to a drop or the like.

Also, even without considering the problem of the lock coming off, the fact that it easily bends when an external force is applied to the front lid is simply a feeling of rigidity and a feeling of unreliability In addition, the front lid comes in contact with the magnetic tape from an unexpected direction, which is inconvenient, and also has a problem in strength against dropping.

(E. Means for Solving the Problems) In order to solve the above-described problems, the magnetic tape cassette of the present invention has a front surface portion of a cassette case, which is opened at least on the front surface and the lower surface, and a rear lid is positioned therein. A stop projection is provided in contact with the rear surface of the front lid in the closed position of the concave portion.

Therefore, in the magnetic tape cassette of the present invention, even when the front lid is likely to be deformed toward the rear side by receiving a force from the outside, particularly from the front, the stopper protrusion contacts the rear surface of the front lid. , The forward deformation of the front lid is prevented,
The rigidity of the front lid is improved, and the strength against falling or the like is also improved.

(F. Embodiment) [FIGS. 1 to 6] Hereinafter, details of the magnetic tape cassette of the present invention will be described in accordance with a first embodiment illustrated.

(A. Cassette Case) [FIGS. 1 to 5] In the figures, reference numeral 2 denotes a cassette case, in which a rectangular shallow dish-shaped upper half 3 and a lower half 4 which are formed of synthetic resin are vertically overlapped. Then, the cassette case 2 in the form of a thin box having a rectangular shape in plan view is formed.

In the cassette case 2, a pair of tape reels 5,
A magnetic tape 7 is wound around the two tape reels 5 and 6.

Numerals 8 and 8 'denote tape outlets formed at both left and right ends of the front surface 2a of the cassette case 2. The magnetic tape 7 extending from one tape reel 5 exits the cassette case 2 from one tape outlet 8, It extends along the portion between the tape outlets 8 and 8 'of the front surface 2a of the cassette case 2 (hereinafter, referred to as "tape withdrawal area") and then enters the cassette case 2 from the other tape outlet 8'. The other tape reel 6 has been reached.

Reference numeral 9 denotes a tape pull-out recess formed in the tape pull-out area of the front surface of the cassette case 2, which is open to the front surface 10, the lower surface 11, and the upper surface 12, and has an opening surface on the upper surface.
The depth of 12 is smaller than the depth of the opening surface 11 on the lower surface, and the depth edge 12a of the opening surface 12 on the upper surface extends straight in the left-right direction.

The other shape and structure of the cassette case 2 will be described later.

(B. Front Cover) [FIGS. 1 to 6] Reference numeral 13 denotes a front cover that covers the entire front surface 2a of the cassette case 2, and is made of synthetic resin.

The front cover 13 has a front portion 14, an upper surface portion 15 protruding rearward from an upper edge of the front portion 14, and side portions 16, 16 'protruding rearward from left and right side edges of the front portion 14 with synthetic resin. It is formed integrally.

Support pins 17, 17 'are protrudingly provided substantially at the center in the vertical direction on the rear side of the inner side faces of the side faces 16, 16', and the support pins 17, 17 'are close to the front end of the side face of the cassette case 2. The front cover 13 is rotatably supported by support holes 18 and 18 'formed in the front portion 14 as shown in FIG.
The cassette is rotated between a closed position for covering the front surface 2a of the cassette case 2 and an open position for opening the front surface 2a above the front surface 2a as shown in FIG. Supported by case 2.

Reference numeral 19 denotes a torsion spring for urging the front lid 13 to rotate in the closing direction. The torsion spring 19 includes a coil portion 19a and two arms 19b and 19c extending from both ends of the coil portion 19a. The portion 19a is fitted externally to a portion of the fulcrum pin 17 of the left side surface portion 16 of the front cover 13 (the left side when the tape cassette 1 is viewed from the front is the left side) located outside the cassette case 2. The tip end of one arm 19b is elastically contacted from above with a spring contact projection 20 projecting from the inner surface of the side surface portion 16 at a position closer to the front portion 14 side than the fulcrum pin 17 and the other arm. 19c is elastically contacted from above with a spring contact projection 21 projecting from the left side surface of the cassette case 2. As a result, the front cover 13 is energized with a turning force in a counterclockwise direction as viewed from the right, that is, a turning force in the closing direction.

The left and right end portions 22a, 22a of the front end of the bottom plate portion 22 of the cassette case 2 project slightly forward from the front surface 2a. 14a, 1
4a are formed, and the upper edges of the notches 14a, 14a abut against the protruding portions 22a, 22a from above so that the front lid 13 is prevented from further rotating in the counterclockwise direction. However, as will be described later, a rear cover described immediately before that prevents the front cover 13 from moving. This position is the lid closing position.

In a state where the front cover 13 is at the closed position (hereinafter, referred to as a “closed position”), the entire front surface 2 a of the cassette housing 2 is covered by the front portion 14 of the front cover 13. The upper surface opening 12 of the tape pull-out recess 9 is covered with the upper surface portion 15 of the front cover 3, and thus the magnetic tape 7 wrapped along the tape pull-out area of the front surface 2 a of the cassette case 2 is moved by the front cover 13. The front side and the upper part will be covered.

23, 23 are support pieces for supporting a rear cover described later, and these support pieces 23, 23 are suspended from the lower surface of the upper surface portion 15 of the front cover 13, and the lower end thereof is located at the center of the front cover 13 in the vertical direction. In the left-right direction, the left and right inner surfaces of the tape pull-out recess 9, that is, the wall 2 located between the tape pull-out recess 9 and the tape outlets 8 and 8 ′.
The inner surfaces 24a, 24a of the fourth and the fourth 24 are opposed to each other. And such support pieces
Circular support holes 23a, 23a are formed at the lower ends of 23, 23, and further, spring abutments 23b, 23b project from the upper part of the front side edge toward each other.

(C. Rear lid) [FIGS. 1, 3 to 6] Reference numeral 25 denotes a rear lid which covers the magnetic tape 7 led out of the cassette case 2 from the rear side and below, and each part thereof is made of synthetic resin. Are formed integrally.

Reference numeral 26 denotes a main portion of the rear cover 25, which has a plate shape long in the left-right direction and has a length substantially equal to the interval between the two support pieces 23 and 23 of the front cover 13; The upper and lower widths of the front portion 14 are slightly smaller than the vertical width of the front portion 14.
26b is formed, and the upper portion of the main portion 26 from the portion where the protruding ridge 26b is formed is slightly rearward from the remaining portion and is bent so as to form a substantially rectangular shape when viewed from the left. .

Notches 26c, 26c are formed in the left and right end surfaces of the main portion 26 at portions corresponding to the protrusions 26b.
Two fulcrum pins 27, 27 coaxial with each other protrude from the side faces 26c, 26c.

Further, a covering ridge 28 extending in the left-right direction is formed at a position close to the lower edge of the front surface of the main portion 26, and further, relatively short arms 29, 29 project rearward from the lower ends of the left and right ends. A small cylindrical guided pin 3 at the tip of the arm 29, 29
0 and 30 protrude toward the side.

Reference numerals 31 and 31 denote pressed portions projecting downward from the left and right end portions of the main portion 26, and the main portion 26 extends from the lower surfaces of the pressed portions 31 and 31.
The space between the upper surface of the front cover 13 and the space between the lower surface of the front surface portion 14 of the front lid 13 and the lower surface of the upper surface portion 15 is slightly smaller.

Then, the fulcrum pins 27, 27 are supported by the support pieces 23, 23 of the front lid 13.
The rear cover 25 is rotatably supported by the front cover 13 behind the front surface portion 14 of the front cover 13, and the guide pin The rear cover 25 is slidably engaged with a guide groove (described later) provided in the cassette case 2 so that the rear cover 25 rotates as shown in FIG. Is moved between the closed position shown in FIG. 1 and the open position shown in FIG. 1 (C).

Reference numerals 32, 32 denote torsion springs for urging the rear lid 25 to rotate in the direction in which the lower end thereof approaches the front lid 13. The torsion springs are provided separately from both ends of the coil parts 32a, 32a and the coil parts 32a, 32a. It has two extended arms 32b, 32b and 32c, 32c,
a, 32a are externally fitted to portions of the fulcrum pins 27, 27 located between the main portion 26 and the support pieces 23, 23, and one arm 32
The tip of b, 32b elastically contacts the spring contact portions 23b, 23b of the support pieces 23, 23 from behind, and the tip of the other arm 32c, 32c is located on the upper surface of the notch 26c, 26c in the front surface of the main portion 26. It is in contact with the continuous position from the front side.

Thus, by the resilience of the springs 32, 32, the rear lid 25 is urged to rotate clockwise as viewed from the right.

(D. Guide Groove) [FIGS. 1, 3 to 5] 33, 33 are used to guide the movement path of the above-mentioned guided pins 30, 30, and to control the attitude of the rear lid 25 with respect to the front lid 13. The guide groove has a function of locking the rear cover 25 in the closed position in addition to the above-described guide function.
4, 24, are formed by providing ridges 33a, 33a on the inner side surfaces 24a, 24a.

The guide grooves 33, 33 are initial guides 34,
34, followed by intermediate portions 35, 35, and further followed by end guides 36, 36. The initial guides 34, 34 are at substantially the same height as the lower edge of the magnetic tape 7 which is stretched along the tape pull-out area on the front surface 2a of the cassette case 2,
Further, it is formed so as to extend substantially along the rotation trajectory of the guided pins 30 of the rear cover 25 when the front cover 13 is at the closed position. Also, the intermediate portions 35, 35 are initial guide portions 34, 34.
Is formed so as to be continuous with the rear end thereof and extend substantially straight upward therefrom, and furthermore, the final guide portions 36, 36 are intermediate portions 35,
The upper end of the wall is formed so as to extend from the right end of the 35 in a clockwise direction as viewed from the right.
Opened at approximately the same height as the upper end surface of 24,24.

The guided pins 30, 30 of the rear cover 25 are slidably engaged with the guide grooves 33, 33, respectively. Therefore, the movement path of the guided pins 30, 30 is the guide groove 33, 33.
Will be guided by

The locking function of the guide grooves 33 with respect to the rear lid 25 will be described later.

(E. Definition of the closing position of the rear lid and covering of the magnetic tape) [FIG. 1 (A)] As described above, the rear lid 25 is provided with a rotational force in the direction in which the lower end approaches the front lid 13. And guide groove 3
Since the initial guide portions 34, 34 of 3, 33 are formed so as to extend substantially along the rotation trajectory of the guided pins 30, 30, of the rear lid 25 in the closed position, the front cover 13 is in the closed position. When it comes, the guided pins 30, 30, as shown in FIG. 1 (A), the front side surfaces substantially perpendicular to the substantially horizontal inner bottom surfaces 34a, 34a of the initial guide portions 34, 34.
It is elastically contacted with 34b, 34b, thereby preventing the rear lid 25 from further rotating in the above direction.

In this state, the position of the rear cover 25 is the closed position. In this state, the main portion 26 faces the front portion 14 of the front cover 13 in a substantially parallel manner with the magnetic tape 7 interposed therebetween. The front end face is located slightly below the lower edge of the magnetic tape 7 and is lightly in contact with or very close to the back surface of the front portion 14 of the front cover 13.

In the closed state, the portion of the magnetic tape 7 that is led out of the cassette case 2 is covered by the front cover 13 from the front side and above, and is covered by the rear cover 25 from the back side and below.

(F. Locking of the rear lid and the front lid) [FIG. 1] Then, in the closed state, the rear lid 25 is prevented from moving to the open position, that is, locked in the closed position. The front cover 13 is locked in the closed position by locking the rear cover 25.

Such a lock is provided by the initial guide portions 34 of the guide grooves 33, 33,
This is performed by the resilience of the springs 32 and 32. Lines L ₁ shown in FIG. 1 (A) is a top 34c of the initial guide portion 34, 34, 34d
An extension of the lock surface (hereinafter referred to as a “lock surface”) and a curve R indicate the lock surfaces 34c and 34c of the outer peripheral surfaces of the guided pins 30 and 30 when the rear cover 25 is rotated in the closed state. rotation locus of points in contact with a straight line l is the line connecting the centers of fulcrum pin 27, 27 of the guide pins 30 and 30 in the closed state also, the straight line L ₂ is the straight line l and times A circumscribed line circumscribing the rotation locus R at a point where the motion locus R intersects;
Locking surface 34c, 34c are formed so as to extend in a direction inclined to稍後filtration closer against external tangents L ₂ (in the drawing is shown in a state tilted about 5 °.).

Therefore, when a force for moving the front lid 13 in the opening direction from the closed state is applied, the force is also applied to the rear lid 25. Since the rear lid 25 is urged to rotate by the springs 32, 32, the guided pins 3 to which a force in the opening direction is applied are applied.
0 and 30 are necessarily pressed against the lock surfaces 34c and 34c in substantially the same direction as the straight line l. And the lock surface 34
Since c and 34c have the inclination described above, the lock surface
34c, the guided pins 30, 30 pressed against the 34c will have a forward moving force, and therefore, the guided pins
30 and 30 are prevented from moving in either direction, thereby preventing the rear cover 25 from moving in the opening direction.
The movement of the front lid 13 in the opening direction is also prevented by preventing the movement of the front lid 25.

Thus, both the rear lid 25 and the front lid 13 are locked in the closed position.

The springs 32 for urging the rear cover 25 to rotate the rotation may be only one of them.
It is also conceivable that it is formed integrally with.

(G. Opening lid) [FIG. 1 (B), FIG. 1 (C)] The movement of the front lid 13 and the rear lid 25 in the opening direction is performed when the tape cassette 1 is mounted on the recording / reproducing apparatus. This is performed by a cover opening means provided in the reproducing apparatus.

That is, notches 14b, 14b are formed in the lower end of the front portion 14 of the front cover 13 at positions corresponding to the pressed portions 31, 31, of the rear cover 25 that is at the closed position, and a tape cassette is formed. When the device 1 is inserted into the cassette insertion portion of the recording / reproducing apparatus, first, the unlocking portion of the lid opening means is relatively inserted into the tape pull-out recess 9 through the cutouts 14b, 14b to move the pressed portions 31, 31 backward. 1, whereby the rear lid 25 is turned counterclockwise as shown in FIG. 1 (B) so as to be in a forwardly inclined position, and the guided pins 30, 30 are brought into the guide grooves 33. , 33 are moved to a position where the initial guide portions 34, 34 and the intermediate portions 35, 35 are continuous, and then a force is applied to the front cover 13 in the opening direction, whereby the front cover 13 is opened. It is turned toward the direction. With this rotation, the position of the rear lid 25 supported by the front lid 13 moves about the fulcrum pins 17 and 17 ′ as the center of rotation, and the movement path of the guided pins 30 and 30 guides the rear lid 25. It moves in the opening direction while being guided by the intermediate portions 35, 35 of the grooves 33, 33 and the final guide portions 36, 36, and reaches the opening position shown in FIG. 1 (C).

Note that while the guided pins 30, 30 are guided in the movement direction by the intermediate portions 35, 35, the front portion 14 of the front cover 13 of the rear cover 25 is provided.
Of the guided pins 30, 30
While the moving direction is being guided by the end guides 36, 36, the inclination becomes smaller, and when reaching the open position, the rear cover 25 is in a posture substantially parallel to the front cover 13.

The operation of moving the front lid 13 and the rear lid 25 in the closing direction is performed in the reverse order of the above-described movement at the time of opening the lid.

As described above, most of the rear lid 25 except for the upper end is largely separated rearward from the magnetic tape 7 before the movement in the opening direction starts, so that the rear lid 25 has static electricity. Even if it does, there is no possibility that the magnetic tape 7 is dragged by the rear lid 25 and moved.

(H. Stopper protrusion) [FIGS. 1, 3 to 5] 37, 37 are stopper protrusions formed on the inner side surfaces 24a, 24a of the walls 24, 24. The ridges 33a, 33a are formed as ridges extending downwardly from the upper end of the front side portion of the front side portion, and slightly in a forward direction in an arc shape, and the front end of the ridge 33a is in the closed position. 13 support pieces 23, 23
And are substantially in contact with the rear surfaces 23c, 23c.

Therefore, even if the intermediate portion of the front lid 13 is pressed from the front as indicated by an arrow 38 in FIG. 1 (A), the rear surfaces 23c, 23c of the support pieces 23, 23 come into contact with the stopper projections 37, 37. Therefore, the intermediate portion of the front lid 13 hardly bends rearward because it cannot be moved rearward, and even if it is bent, the guide pin 30, 30 of the rear lid 25 is hardly bent. It does not move to the position where the lock is released, and the reliability of locking the front lid 13 and the rear lid 25 increases.

(G. Effects of the Invention) As is clear from the above description, the magnetic tape cassette of the present invention has a structure in which a tape reel on which a magnetic tape is wound is rotatably housed except for both ends on the front surface of a cassette case. At least a concave portion opened at the lower surface and the front surface is formed at the portion, and a portion of the magnetic tape drawn out of the cassette case is positioned so as to extend along the front surface of the concave portion, and is rotatably provided at both left and right ends of the cassette case. A front lid is provided that is pivoted between a closed position that is supported and covers the front surface of the cassette case and an open position that opens the front surface of the cassette case, and is rotatably provided on the rear side of the front lid. When the front lid is in the closed position, it is positioned close to the back side of the magnetic tape and covers the magnetic tape in cooperation with the front lid. I'll separate The lid is provided after being characterized in that the stopper projection is provided in contact with the rear surface portion of the front lid in the closed position of the recess of the cassette case.

Therefore, in the magnetic tape cassette of the present invention, even when the front lid is likely to be deformed toward the rear side by receiving a force from the outside, particularly from the front, the stopper protrusion contacts the rear surface of the front lid. , The rearward deformation of the front lid is prevented,
The rigidity of the front lid is improved, and the strength against falling or the like is also improved.

In the above embodiment, the present invention is applied to a magnetic tape cassette in which the rear cover is locked in the closed position, whereby the front cover is also locked. Although the advantage has been shown to be certain, the present invention can be applied to other than such a magnetic tape cassette, whereby at least the rigidity of the front lid is increased and the reliability is improved. Also increases.

In addition, the rear surface of the front lid that comes into contact with the stopper projection is not limited to the rear surface of the support piece, and the specific shapes and structures shown in the above-described embodiments are only a few in implementing the present invention. They are merely examples and do not limit the technical scope of the present invention.

[Brief description of the drawings]

1 to 6 show an embodiment of the magnetic tape cassette of the present invention. FIG. 1 shows the movement of the front lid and the rear lid from the closed position to the open position from (A) to (C). 2) is an enlarged vertical sectional view of a main part shown with time, FIG. 2 is a perspective view of a closed state, FIG. 3 is a perspective view of an opened state, and FIG. 4 is FIG. 1 (A).
5, a partially omitted enlarged cross-sectional view along the line IV-IV, FIG. 5 is a partially exploded perspective view, and FIG. 6 is a partially cut-away view of both ends of the rear cover and a support portion of the front cover. FIG. 7 is an enlarged vertical sectional view of a main part showing a problem of the conventional magnetic tape cassette. DESCRIPTION OF SYMBOLS 1 ... Magnetic tape cassette, 2 ... Cassette case, 2a ... Front, 7 ... Magnetic tape, 9 ... Recess, 13 ... Front lid, 23c ... Rear surface part of front lid, 25 ... Rear lid, 37 ... Stopper protrusion

Claims (1)

(57) [Claims] 1. A cassette case in which a tape reel on which a magnetic tape is wound is rotatably housed, and a recessed portion opened at least on the lower surface and the front surface is formed in a portion excluding both ends of the front surface of the cassette case. The part drawn out is positioned so as to extend along the front surface of the recess, and is rotatably supported by the left and right ends of the cassette case. The lid position that covers the front surface of the cassette case and the front surface of the cassette case are open. A front lid that is pivoted between an open position and a magnetic tape when the front lid is in the closed position. And a rear lid which is positioned so as to cover the magnetic tape in close proximity to the front lid and cooperates with the front lid, and is separated from the magnetic tape when the front lid moves to the open position. Out of the closed position A magnetic tape cassette, wherein a stopper projection is provided in contact with the rear surface of the front cover.