JPH0831142A - Tape cassette - Google Patents

Abstract

PURPOSE:To surely engage and hold a lid in the manner of increasing the spring force of an arm to pressurize a lid lock and reducing the force for moving the lid lock by providing a spring fulcrum brought in contact part between a turning center of the arm of the spring and the contact part of the lid lock. CONSTITUTION:The spring 25 provided with two arms 25a, 25b is interposed- between a cassette easing 1 consisting of a pair of upper half 1a and lower half 1b, wherein an information recording tape is housed, and the lid 12 for covering a part of the tape exposed to a mouth part 3 of the casing 1 so as capable of opening and closing. The lid 12 is pressed by one arm 25a of the spring 25 and also the lid lock 26 is pressed by another arm 25b to engage and hold the lid 12 by the lock 26 when the lid 12 is closed. The fulcrum D is provided for supporting the another arm 25b by bringing in contact between the turning center A of the another arm 25b of the spring 25 and the contact part C of the lock 26. Since the fulcrum for supporting the arm 25b is moved from the turning center A to the fulcrum D as the result that a rib 29 is arranged, the force exerted to the lock 26 from the arm 25b is increased, then the lid 12 is surely engaged and held.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention applies the spring force of one spring having two arms to a lid and a lid lock, and the spring force of one arm closes the lid to form an information recording tape. The present invention relates to a tape cassette that wraps and protects it, and presses a lid lock by the spring force of the other arm to engage and hold the lid in a closed state. is there.

[0002]

2. Description of the Related Art Conventionally, as a tape cassette provided with a spring having two arms of this type, for example,
There is one as shown in FIGS. 9 and 10. 9 and 10 show an 8 mm video tape cassette, in which 1 is a cassette housing and 2 is a lid which covers the mouse portion 3 on the front surface of the cassette housing 1 in an openable and closable manner. The cassette housing 1 is composed of two members, an upper half 1a and a lower half 1b, and the lid 2 is composed of two members, a front lid 2a and a back lid (not shown).

The front lid 2a has side plates 4 and 4 at both left and right ends thereof, and a rotating shaft 5 is provided on the inner surface of each side plate 4, and the rotating shafts 5 and 5 form the front lid 2a. It is rotatably supported by the upper half 1a. Then, as shown in FIGS. 9 and 10, the coil portion 6c of the torsion coil spring 6 having the two arms 6a and 6b is loosely fitted to the one rotating shaft 5, and the one arm 6a is The arm 6b is locked to the front lid 2a, and the other arm 6b is locked to the lid lock 7.

Due to the spring force of the torsion coil spring 6,
As shown in FIG. 9, when the lid 2 is closed, the lock claw 7a of the lid lock 7 engages with the stopper 8 of the front lid 2a, whereby the lid 2 is locked in the closed state. When releasing the closed state of the lid 2, the lid lock 7 is rotated by a release pin provided in the cassette in the 8 mm video camera to disengage the lock claw 7a from the stopper 8. Done by. As a result, the lid 2 is unlocked by the lid lock 7, and the front lid 2a is lifted against the spring force of the torsion coil spring 6 to open the lid 2 as shown in FIG.

It should be noted that α ₀ shown in FIG. 9 indicates a torsion angle when the torsion coil spring 6 is assembled. This torsion angle α ₀
Is set to about 50 °, and the arm 6b is elastically deformed and attached from the state of the broken line showing the free state of the arm 6b to the set state shown by the solid line. Further, α ₁ shown in FIG. 10 indicates a twist angle when the lid 2 is fully opened, and the twist angle α ₁ can be expanded to about 145 °.

[0006]

However, in the conventional tape cassette as described above, when the lid 2 is locked, one arm 6a of the torsion coil spring 6 having the two arms 6a and 6b is used for the front. Lid 2a
The lid 2 to close the lid 2 and the other arm 6b.
Since the lid lock 7 is urged to engage and hold the front lid 2a, the following problems have been considered.

That is, due to the action of one torsion coil spring 6, a torque having the same magnitude as the torque for closing the lid 2 is also applied to the contact portion with the lid lock 7 on the opposite side. Since the spring force of the spring 6 increases or decreases in proportion to the magnitude of the torsion angle α, the torsion angle α
In the open state of the lid 2 in which the angle is increased, the force applied to the lid lock 7 increases as the angle increases. Therefore, in the conventional example of FIGS. 9 and 10, the twist angle α _{0 in} the closed state is 50 °, whereas the twist angle α _{1 in the} open state is 145 °, so the force applied to the lid lock 7 is It is almost tripled. Therefore, the release force of the lid lock 7 increases almost three times as the spring force of the torsion coil spring 6 increases, but when this lock release force is large, the release mechanism also becomes large, which is not preferable.

On the other hand, when the set position of the lid lock 7 is away from the pivot shaft 5 of the lid 2, the pushing force of the lid lock 7 decreases in inverse proportion to the length of the arm.
In this case, the force for locking the lid 2 in the closed state cannot be secured. Further, in some three-lid tape cassettes having three lids for opening and closing the mouse portion, a large movable space around the lid lock 7 cannot be secured. In this case, the lid lock is used. Since the length of the arm from the rotation center of 7 to the contact portion of the arm 6b is limited, the required lid lock 7
There is a problem that it becomes impossible to obtain the releasing force of.

The present invention has been made in view of the above conventional problems, and the force for moving the lid lock is increased by increasing the spring force of the arm that presses the lid lock without changing the strength of the spring. An object of the present invention is to provide a tape cassette that can securely hold and hold the lid while keeping it small.

[0010]

In order to solve the above-mentioned problems and the like and to achieve the above-mentioned objects, the present invention accommodates an information recording tape, for example, as shown in FIGS. A cassette housing 1 including a pair of upper and lower halves 1a and 1b, and a mouse portion 3 of the cassette housing 1.
Lid 12 that wraps part of the tape exposed on the back
A spring 25 having two arms 25a and 25b between
And the lid 12 is urged by one arm 25a and the lid lock 26 is urged by the other arm 25b so that the lid 12 is engaged and held by the lid lock 26 when the lid 12 is closed. In the tape cassette, the rotation center A of the other arm 25b of the spring 25
And a contact portion C of the lid lock 26, a spring fulcrum D for supporting the other arm 25b is provided.

Further, the spring fulcrum D of the tape cassette of the present invention is, for example, as shown in FIGS. 3 to 8, the upper half 1a.
It is good that it is the rib 29 extended from.

[0012]

The present invention has the above-mentioned configuration,
Assuming that the magnitude of the torque applied by the spring 25 does not change, the fulcrum that supports the other arm 25b moves from the rotation center A to the spring fulcrum D by providing the rib 29, so that the other arm 25b does not move. Lid lock 2
The force applied to 6 is increased by the length of the arm. Therefore, the force of the arm 25b pushing the lid lock 26 can be increased without changing the strength of the entire spring 25, and the lid 12 can be securely engaged and held.

A rib 2 extending from the upper half 1a
By setting 9 as the spring fulcrum D, the spring force of the arm 25b can be increased by only slightly changing the shape of the upper half 1a.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show an embodiment of the present invention and are views of a tape cassette used in electronic equipment such as a video camera. In addition, in FIGS. 1 to 8, FIG.
Also, the same parts as those in FIG.

In FIG. 1, reference numeral 1 denotes a cassette housing made of a synthetic resin having an appropriate rigidity. The cassette housing 1 includes a pair of upper and lower halves 1a and 1b which are superposed on each other. It consists of In the cassette housing 1, the supply side reel 10 and the winding side reel 1
1 is rotatably accommodated, and the information recording tape T pulled out from the supply reel 10 has one opening 3
0a, the tape guide 31a guides the mouse unit 3 on the front surface of the cassette housing 1, and the other opening 3
The tape is wound around the take-up reel 11 by being guided by the tape guide 31b provided on the winding reel 0b. The lid 1 is attached to the mouth portion 3 and the openings 30a and 30b of the cassette housing 1.
2 is supported so that it can be opened and closed, and the lid 12 is in a closed state.
Allows the tape T that crosses the front surface of the cassette housing 1 to
Protects.

The lid 12 is composed of three lids, that is, a front lid 13, a top lid 14, and a back lid 1.
And 5. The front lid 13 is arranged so as to cover the front surfaces of the mouth portion 3 and the openings 30a and 30b, and side plates 16 are provided at both ends in the left-right direction. Rotation shafts 17 projecting inward are formed on the inner surfaces of the side plates 16, 16 so as to face each other. The rotation shafts 17, 17 are rotatably supported by the lower half 1b. The front lid 13 rotates about the rotating shafts 17 and 17 to open and close.

The top lid 14 is arranged so as to cover the upper surfaces of the mouth portion 3 and the openings 30a and 30b, and bearings 14a and 14a are provided on both sides of the front end thereof. The fulcrum shafts 13a and 13a provided on both sides of the upper end of the front lid 13 are rotatably fitted to these bearings 14a and 14a, respectively, whereby the top lid 14
Is rotatably connected to the front lid 13. Side plates 18, 18 are provided on both sides of the top lid 14, respectively, and first cam bosses 20, 20 projecting inward so as to face each other are provided on inner surfaces of rear end portions of the side plates 18, 18, respectively. Has been formed. The first cam bosses 20 and 20 are movably engaged with the first cam grooves 21 and 21 provided on both side surfaces of the upper half 1a.

Further, the back lid 15 is obliquely arranged in the mouth portion 3 on the back side of the front lid 13 and the top lid 14, and the shaft pins 15 are provided at both upper end portions thereof.
a are formed respectively. These shaft pins 15a,
15a is a bearing 14 provided at the lower rear end of the top lid 14.
The back lid 15 and the top lid 14 are rotatably connected to the b and 4b, respectively. Side plates 2 are provided on both sides of the back lid 15.
2, 22 are provided respectively, and these side plates 22, 22 are provided.
Second cam bosses 23, 23 are formed on both sides of the lower end of the boss. Then, these second cam bosses 23,
23 is the second cam groove 2 formed on the inner surface of the lower half 1b.
4 and 24 are movably engaged with each other.

As shown in FIGS. 1 to 7, the first cam groove 21 rises in a convex arc shape from the front side on both side surfaces of the upper half 1a and changes linearly from the middle to the rear. It is formed so as to extend. By the first cam groove 21 guiding the first cam boss 20 in such a shape, the top lid 14 moves in the front-rear direction while maintaining a substantially horizontal posture.

Further, the second cam groove 24 is formed in
As shown in FIG. 3, the lower half 1b is formed so as to rise in a concave arc shape from the front side of the lower end on both inner surfaces of the front portion and change from the middle portion to rise upward. By the second cam groove 24 guiding the second cam boss 23 in such a shape, the back lid 15 is raised while rotating from the initial inclined state and becomes substantially horizontal above the cassette housing 1. To move.

Such three lids 13, 14, 15
The lid 12 is opened and closed by the movement of, and the exposed portion of the mouth portion 3 and the openings 30a and 30b of the tape T is protected. A force for closing the lid 12 is applied between the cassette housing 1 and the front lid 13 in association with the movement of the lid 12 and the lid 1 closed.
A torsion coil spring 25, which is a specific example of a spring that applies a force for holding the device 2 in a closed state, is interposed.

This torsion coil spring 25 is used for the lid 12
Arm 2 for urging front lid 13 to close
5a and an arm 25b for urging the lid lock 26 toward the front lid 13 side, and these arms 25a, 25b extend in the directions away from each other from both ends of the central coil portion 25c. ing. The coil portion 25c of the torsion coil spring 25 has the front lid 13
Is loosely fitted to one of the pair of rotating shafts 17 provided in the. Then, one arm 2 of the torsion coil spring 25
5a is locked from above by a locking piece 27 formed on the inner surface of one side surface plate 16 of the front lid 13, thereby biasing the front lid 13 to the closing side. The other arm 25b of the torsion coil spring 25 is pressed against the lid lock 26 swingably supported by the lower half 1b from above, thereby urging the lid lock 26 toward the front lid 13. .

The lid lock 26 includes a rotating shaft 26a rotatably fitted to a bearing provided on the lower half 1b, and a lock pressure receiving portion 26b to which the other arm 25b of the torsion coil spring 25 is pressed. The front lid 13 includes a lock claw 26c that is engaged with a stopper 13b provided on the inner surface of the front lid 13, and a lock release portion 26d that is pressed by a release pin 28 provided in a recording / reproducing apparatus or the like in which the present cassette tape is mounted. ing. Both ends of the rotating shaft 26a are supported by the bearings of the lower half 1b, and a lock pressure receiving portion 26b is formed on the upper portion on the back side thereof. Further, a lock releasing portion 26d is extended below the rotating shaft 26a, and a lock claw 26c is formed to project on the opposite side of the lock pressure receiving portion 26b in the middle thereof.

Further, the upper half 1a is provided with a rib 29 which comes into contact with a middle portion of the other arm 25b of the torsion coil spring 25, that is, a portion between the base portion of the arm 25b and the lock pressure receiving portion 26b. There is. The rib 29 extends forward and downward along the first cam groove 21,
The middle part of the arm 25b is pressed downward with an appropriate force to increase the force applied from the torsion coil spring 25 to the lid lock 26. The tip of the rib 29, which presses the middle portion of the arm 25b, serves as a spring fulcrum D.

The opening / closing operation of the lid 12 of the tape cassette having such a structure is performed as follows, for example. First, the case of opening the lid 12 will be described.
In this case, when the tape cassette is attached to a predetermined electronic device such as a video camera, the state shown in FIGS.
As shown in FIG. 5, the unlock pin 28 of the cassette computer built in the video camera or the like is used as the unlock portion 2 of the lid lock 26.
Abut on 6d and push it back. As a result, the lid lock 26 rotates clockwise about the rotation shaft 26a. As a result, the lock claw 26c is pulled out, the engagement with the stopper 13b is released, and the three lids 13, 1 are released.
4,15 movements are possible. At this time, a push-up member (not shown) for pushing up the front lid 13 is arranged at a lower edge of a part of the front lid 13.

Next, relative movement of the tape cassette in the vertical direction with respect to the cassette occurs, whereby the front lid 13 is pushed up by the push-up member against the spring force of the torsion coil spring 25, and its rotating shaft 17 is moved. As a center, the front lid 13 rotates counterclockwise in FIG. As a result, as shown in FIGS. 6 and 7, the top lid 14 is guided by the first cam groove 21 to move obliquely rearward and upward as described above, and the back lid 15 is moved.
Also, as described above, the guide 12 is guided by the second cam groove 24 to move diagonally upward and rearward, and thereby the lid 12 that has closed the mouth portion 3 and the openings 30a and 30b is opened.

On the other hand, when the lid 12 is closed to eject the tape cassette, the operation opposite to the opening operation is performed. That is, when the ejecting operation of the tape cassette is started by pressing the eject button of the cassette computer, the push-up member retracts, so that the rotation shaft 1 of the front lid 13 is moved.
The front lid 13 is pushed down by the spring force of the torsion coil spring 25 in which the coil portion 25c is loosely fitted in the coil 7. As a result, three lids 13, 14, 1
5 changes from the state shown in FIGS. 6 and 7 to the state shown in FIG. 5, whereby the lid 12 is closed so as to wrap the tape T.

Now, the rotation center, which is the common base end of the two arms 25a and 25b, is the fulcrum A on the rotation shaft side, and the locking piece 2 of the front lid 13 that supports the tip of one arm 25a.
The support center of 7 is the action point B on the lid side, and the other arm 25b
Lock pressure receiving portion 26 in which the tip of the spring contacts the lid lock 26
The contact portion of b is the lock side action point C, and the contact portion of the other arm 25b where the rib 29 abuts as described above is the spring fulcrum D, and from the rotation axis side fulcrum A to the lid side action point B. The length is x, the length from the rotary shaft side fulcrum A to the lock side action point C is y, and the length from the lock side action point C to the lid lock 26.
Is z, the length from the lock side action point C to the spring fulcrum D is s, and the length from the spring fulcrum D to the rotary shaft side fulcrum A is t. .

Then, the pressing force exerted on the lid side action point B by the spring force of one arm 25a is FF, the pushing force exerted on the lock side action point C by the spring force of the other arm 25b is FR, and the spring support point D from the other. If the force acting on the arm 25b of F is F1, then FF × x = FR × s (1) from the balance of the moments acting on the torsion coil spring 25. At this time, if the torsional force generated at the lock side action point C by simply twisting the torsion coil spring 25 is F0, the force F1 acting on the spring fulcrum D is the other arm 25b.
To press the lid lock 26 against the lid lock 26, the pressing force FR is the twisting force F0 plus the force F1, that is, FR = F0 + F1 (2). Compared with the case of the conventional tape cassette, in the conventional case in which the spring fulcrum D by the rib 29 is not provided, the force acting from the other arm 6b to the lock side action point is
Only the torsional force F0 generated by twisting the torsion coil spring 25 is used. However, when the rib 29 is provided and the spring fulcrum D is provided in the middle of the other arm 25b as in the present embodiment, the spring fulcrum D is provided. F1 and torsional force F acting on
It becomes the force FR which added 0.

Therefore, according to this embodiment, the force F1 and the twisting force F0 are applied to the lock side action point C of the lid lock 26.
The pressing force FR added with and can be applied, and the rib 2
By merely providing the spring fulcrum D by 9, the force FR pushing the lid lock 26 can be increased by the force F1 as compared with the conventional case. As a result, the force F that pushes the lid lock 26
Assuming that R is constant, according to the present embodiment, the arm length z of the lid lock 26 can be made shorter than that of the conventional one. Since the arm of the lid lock 26 is rotationally displaced as shown in FIG. 8, the space may be small and the electronic device such as a video camera can be downsized by the length z of the arm. be able to.

Further, the torque acting on the lid side action point B from one arm 25a is FF × x, whereas the torque acting on the lock side action point C from the other arm 25b is F.
Since it is R × s, the length s of the other arm 25b can be made close to the length x of the one arm 25a and can be made equal in some cases. Therefore, the pressing force FR of the lid lock 26 can be made close to the pressing force of the front lid 13 and can be made equal in some cases, and these forces FF and FR can be obtained.
Can be reduced or eliminated.

As described above, the present invention is not limited to the above embodiment. For example, in the above embodiment, the rib 29 is extended from the upper half 1a and the spring fulcrum D is formed.
Although the example of providing the upper half 1a or the lower half 1 has been described, a member such as the rib 29 is provided as a separate member.
It can be configured to be fixed to b with a screw or the like. Furthermore,
In the above-described embodiment, the example in which the torsion coil spring 25 is applied as the spring has been described. However, in addition to this, for example, a spring member in which a ring is fixed to the middle part of the leaf spring can be applied.

Furthermore, the present invention can be applied not only to an 8 mm video cassette, but also to this, for example, V
It can be used as a tape cassette for TR or a tape cassette for other electronic devices. As described above, the present invention can be variously modified without departing from the spirit thereof.

[0034]

As described above, according to the present invention,
Since the spring fulcrum that makes contact is provided between the rotation center of the arm of the spring and the contact portion of the lid lock, the force with which the arm pushes the lid lock can be increased without changing the strength of the entire spring. Therefore, if the force pushing the lid lock is constant, the length of the arm of the lid lock can be shortened in the present invention as compared with the conventional one, whereby the accommodation space of the lid lock is small. As a result, the size of the electronic device such as a video camera can be reduced by the length of the arm.
Furthermore, the length of the arm contacting the lid lock can be made close to, and in some cases equal to, the length of the arm that urges the lid, and therefore the pressing force of the lid lock can be made close to the pressing force of the front lid. In some cases, the effect that they can be equalized is obtained.

By using the rib extending from the upper half as a spring fulcrum, the spring force of the arm can be made larger than that of the conventional one by only slightly changing the shape of the upper half.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is an external perspective view with a lid closed.

FIG. 2 is an external perspective view showing a state in which the lid is fully opened.

FIG. 3 is a side view showing an enlarged main part of the tape cassette of FIG.

FIG. 4 is a side view showing a part of FIG. 2 in section.

FIG. 5 is a side view showing a state in which the lid lock is rotated by the release pin.

FIG. 6 is a side view showing a state in which the lid is fully opened.

FIG. 7 is an explanatory view showing a cross section of three lids of the same.

FIG. 8 is an explanatory diagram showing a relationship between a spring and a lid lock.

FIG. 9 is an explanatory view showing a cross section of a main part of a conventional tape cassette with a lid closed.

FIG. 10 is an explanatory view showing a cross section of a main part of the same with the lid open.

[Explanation of symbols]

 1 Cassette Housing 1a Upper Half 1b Lower Half 3 Mouse Part 12 Lid 13 Front Lid 13b Stopper 14 Top Lid 15 Back Lid 17 Rotating Shaft 20 First Cam Boss 21 First Cam Groove 23 Second Cam Boss 24 Second Cam groove 25 Torsion coil spring (spring) 25a, 25b Arm 26 Lid lock 26a Rotating shaft 26b Lock pressure receiving portion 26c Lock claw 26d Lock releasing portion 28 Release pin 29 Rib A Rotating shaft side fulcrum (rotating center) B lid side Point of action C Point of action on lock side D Spring fulcrum T Tape

Claims (2)

[Claims] 1. A cassette housing composed of a pair of upper and lower halves containing an information recording tape and a part of the tape exposed in the mouse portion of the cassette housing, which is openably and closably wrapped. A spring having two arms is interposed between the lid and one of the arms, one arm biases the lid and the other arm biases the lid lock, and when the lid is closed, the lid lock engages the lid. In the tape cassette adapted to hold together, a spring fulcrum that supports the other arm of the spring by contacting between the rotation center of the other arm and the contact portion of the lid lock is provided. Characteristic tape cassette. 2. The tape cassette according to claim 1, wherein the spring fulcrum is a rib extending from the upper half.