JPH11339434A - Magnetic tape cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic tape cartridge having a smoothly turnable lid at a low cost. SOLUTION: The magnetic tape cartridge 1 is composed of a lid lock member 40 which is pressed by a lid lock spring 16 to a lower cartridge 2b to couple with a recess of the lower cartridge 2b to lock a lid 30 from releasing and pressed to an upper cartridge by a release lever to release from the recess, thus releasing the lid 30 from locking at opening of the lid and lid spring 15 composed of a coil spring mounted on a support shaft 14 of the upper cartridge 2a to press the lid 30 in a closing direction, and the lid spring 15 has a coil composed of a compression spring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lid for opening and closing an opening for drawing out a magnetic tape, and a magnetic tape cartridge having a lid spring for urging the lid in a closing direction.

[0002]

2. Description of the Related Art Conventionally, as a magnetic tape cartridge used as a recording medium for a computer or the like, a magnetic tape is wound around one reel, and this reel is rotatable inside a cartridge case composed of an upper cartridge and a lower cartridge. There is a magnetic tape cartridge housed in the company.

In use, the magnetic tape cartridge is used such that the magnetic tape is pulled out from the opening of the cartridge case. When not in use, with the magnetic tape completely wound on the reel, a leader tape (an engaging means for a device such as a computer to introduce the magnetic tape into the tape path) attached to the end of the tape is used. Along with being locked to the end face portion of the cartridge case, the reel is locked by a locking means such as a reel lock so as to prevent unexpected rotation.
The opening is closed by a lid that can be freely opened and closed.

Next, a conventional lid and its locking structure will be described. Inside the aforementioned cartridge case,
The magnetic tape is wound around a reel appropriately mounted rotatably, and the leader tape at the tip is located at the opening,
A lid is provided to close this opening. The reel is composed of an upper reel and a lower reel each having a gear portion formed on the outer periphery.

FIG. 7 shows a basic mounting structure of the lid.
As shown in FIG. 7, the lid 60 is mounted on the support shaft 14 of the upper cartridge 2a, and is urged by a lid spring 65 in the closing direction (the direction of arrow A). The coil spring 65c of the lid spring 65 is mounted on the support shaft 14, and one leg 65b is connected to the frame 2d of the upper cartridge 2a.
And the other leg 65 a is supported by the concave portion 67 of the lid 60.

[0006] A lid lock member 70 for locking the lid opening and closing movement is provided near the support shaft 14. The lid lock member 70 is mounted so as to be incorporated in the lid 60 so as to be slidable in the thickness direction of the cartridge. And the lid lock member 70 is
The lid 60 is urged upward (in the direction of arrow U) in FIG. 7 by a lid lock spring 16, and its upper end is engaged with the concave portion of the lower cartridge to lock the lid 60 so as not to open.

The lid 60 and the cartridge case are made of a composite material of polycarbonate and glass fiber in order to realize accuracy and flame retardancy. In addition, the lid lock member 70 has a POM to reduce friction.
(Polyacetal) and other materials with excellent slipperiness. Further, the support shaft 14 is integrally formed as a part of the upper cartridge 2a from the viewpoint of accuracy and cost, and is provided in the lid 60, and the shaft hole 63 through which the support shaft 14 passes also has the same reason. It is formed integrally with the lid 60.

[0008]

By the way, materials which can realize accuracy and flame retardance represented by the above-mentioned polycarbonate and the like have a large friction coefficient as a synthetic resin (friction coefficient μ = 0.4 to less). 0.6). Therefore, the lid 60 may stop during the rotation operation due to the rotational resistance between the support shaft 14 and the shaft hole 63. In addition, there is a problem that a load on a drive of a device such as a computer increases when the lid is rotated.

Further, when the lid 60 is opened, the lid lock member 70 operates while being pushed by the door opening lever of the drive toward the upper cartridge 2a, so that the thrust friction between the lid 60 and the upper cartridge 2a increases, Not only the opening operation becomes heavy, but also wear powder is generated.
On the other hand, when the lid 60 is closed, by the force of the lid spring 65,
It must overcome the reaction force of the leader tape that contacts the inner surface of the lid 60. In addition, when the lid 60 is closed, the lid lock member 70 pushes the lower cartridge, so that friction between the lid lock member 70 and the lower cartridge occurs, and the reaction force when the lid lock member 70 pushes the lower cartridge causes the lid 60 to move upward. A thrust load is applied between the cartridges 2a, and friction occurs at this portion. This frictional force is a large frictional force between both members, such as polycarbonate, so that not only the frictional force is large and a closing failure occurs but also a failure such as dropout due to abrasion powder or the like may occur.

If the urging force of the lid spring itself is simply increased, not only does the force required to open the lid increase, but also the abrasion increases, and if the size of the lid spring itself is increased, it is necessary to store the lid spring. Space also increases. Further, after performing the lid opening / closing operation many times, abrasion powder is generated, and a failure such as dropout may occur.

Here, by changing the material of the support shaft 14 and the shaft hole 63 to a material having good slidability such as polyacetal, the above-mentioned trouble can be solved. However, in order to prevent the flame retardancy and the accuracy of the cartridge and the lid from deteriorating, the cartridge 2a and the support shaft 14, and the lid 60 and the shaft hole 63 are formed by a separate structure or two-color molding. And cost disadvantages.

Accordingly, the present invention has been made based on the above background, and an object of the present invention is to provide a magnetic tape cartridge capable of smoothly rotating a lid at a low cost.

[0013]

SUMMARY OF THE INVENTION The object of the present invention is to provide a magnetic tape reel which is housed in upper and lower cartridges and has a magnetic tape wound thereon, and an opening provided for drawing out the magnetic tape. A lid rotatably mounted on the provided support shaft, and a lid lock spring that urges the lower cartridge side to lock the opening of the lid by engaging with a concave portion of the lower cartridge;
When the lid is opened, the lid is pressed against the upper cartridge side by an opening lever to disengage the recess and release the locked state of the lid, and a lid lock member attached to a spindle of the upper cartridge, And a lid spring formed of a torsion coil spring for urging the spring in the closing direction, wherein the coil portion of the lid spring is formed of a compression spring.

According to the present invention, when the lid is opened,
By the compression of the coil portion formed by the compression spring, a reaction force opposing the pressing force of the release lever acts, and the friction loss between the lid and the upper cartridge is reduced. On the other hand, when the lid is closed, the lid lock member pushes the lower cartridge, so that a slight friction occurs between the lid lock member made of a material having good slidability and the lower cartridge. The force opposing the reaction force when the cartridge is pushed also acts by the compression of the coil portion, and the friction loss between the lid and the upper cartridge is reduced. Therefore, the lid can be smoothly rotated without the lid being stopped in the middle of the rotation operation due to the rotational resistance. Further, since the coil portion of the lid spring is merely made of a compression spring, the cost is not significantly increased.

Here, the compression spring is similar to a general torsion coil spring in appearance, but is a spring whose coil portion has compressibility.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an exploded perspective view of a magnetic tape cartridge according to one embodiment of the present invention. In a magnetic tape cartridge 1 shown in FIG. 1, a magnetic tape 20 is wound around one reel 3 in which an upper reel 4 and a lower reel 5 are, for example, ultrasonically welded, and the reel 3 is connected to an upper cartridge 2a and a lower cartridge 2b. Are rotatably housed in a cartridge case fastened by screws 19.

In the reel 3, the upper reel 4 has an upper flange 4a, and a concave portion is provided at a center portion thereof. A gear 4b is formed on the outer periphery of the upper flange 4a. A ring-shaped bearing 6 is press-fitted and fixed in a circular rib formed in the concave portion, and a spring plug 7 is press-fitted and fixed in a hole at the center of the bearing. Then, a reel spring 8 is attached to the spring plug 7.
Is attached, and presses the reel 3 downward and holds the reel 3 rotatably.

When the cartridge is not used, the reel 3 is locked by the reel locks 50 and 51 appropriately urged by the reel lock spring 12 so as not to rotate unexpectedly. Further, the magnetic tape cartridge 1
When the magnetic tape 20 is not used, the leader tape 21 attached to the end of the magnetic tape (when a device such as a computer connects the magnetic tape 20 to the tape path) in a state where the magnetic tape 20 is completely wound around the reel 3. (Introduction means) is locked at the tip of a hook 18 incorporated near the side of the cartridge.

An opening 26 for drawing out the magnetic tape 20
Has a lid 30 that can be opened and closed in the cartridge plane direction.
Are attached by being urged appropriately by a lid spring 15 for urging the lid. When the cartridge is not used, the lid 30 is locked so as not to be opened by a lid lock member 40 appropriately urged toward the lower half 2b by the lid lock spring 16. Further, a leader tape 21 which engages with an engaging means for introducing the magnetic tape 20 into the tape path of the recording / reproducing apparatus is connected to the magnetic tape 20 by, for example, a splice.

FIG. 2 shows a basic mounting structure of the lid according to one embodiment of the present invention. As shown in FIG. 2, the lid 30 is mounted on the support shaft 14 and is urged by a lid spring 15 in the closing direction (the direction of arrow A). The lid spring 15 is a compression spring whose coil portion 15c is formed by a gap winding. And the lid spring 15
The coil part 15c is mounted on the support shaft 14, one leg 15a is supported by the frame 2d of the cartridge case 2a, and the other leg 15b is
7 supported. Since the coil portion 15c of the lid spring 15 is merely a compression spring as compared with the related art, the cost is not significantly increased.

FIG. 3 shows a state where the lid spring 15 and the lid 30 are assembled to the support shaft 14. As shown in FIG.
The boss 40 a of the lid lock member 40 is inserted into the lid lock spring 16, and the lid lock member 40 is assembled to the lid lock spring 16.
0 is upward in the figure by the lid lock spring 16 (arrow U
Direction), the upper end portion 40b of the lid lock member 40 projects from the hole 31 of the lid 30. When the protruding upper end portion 40b engages with the concave portion of the lower cartridge 2b, the lid 30 cannot rotate.

When the lid 30 is opened, as shown in FIG. 4, a pressing force is applied in the direction of arrow L, that is, in the direction of the upper cartridge 2a, by the release lever of the drive.
Must be opened in the direction of arrow B. Here, a force is applied in the L direction by the release lever, but since the coil portion 15c of the lid spring 15 is a compression spring, the coil portion 15c itself can obtain a reaction force opposing the L direction by being compressed. Therefore, friction loss due to contact between the lid 30 and the upper cartridge 2a can be reduced.

Further, when the lid is closed, a force for urging the lid lock member 40 toward the lower cartridge 2b by the lid lock spring 16 acts, and the lid lock member 40 abuts on the lower cartridge 2b. The lid 30 is urged toward the upper cartridge 2a by the force of the lock member 40. However, also in this case, since the coil portion 15c of the lid spring 15 can be compressed, a reaction force against the force applied from the lid lock member 40 is obtained, and both the lid 30 and the lid 30 made of a material having a large friction coefficient such as polycarbonate are used. Friction loss with the upper cartridge 2a can be reduced. Therefore, since the friction between the lid 30 and the upper cartridge 2a can be reduced, the lid does not stop in the middle of the rotation operation due to the rotational resistance, the problem of poor closing does not occur, and the rotation of the lid can be smoothly performed. I can do it. Here, the lid lock member 4
No. 0 does not pose a problem because a friction material having good slidability and a small frictional force, such as POM, is not generated even when it comes into contact with the lower cartridge 2b and the frictional force is small.

The compression force of the coil portion 15c is preferably equal to or more than the non-compression force of the lid lock spring 16 for biasing the lid lock member 40, more preferably 1.2 to 1.5 times. Is preferable. As described above, since the lid lock member 40 is made of POM or the like having excellent slipperiness, the friction coefficient is smaller than that of the lid 30 and the friction caused by the contact between the lid lock member 40 and the lower cartridge 2b does not cause much problem. This is because it is better to float the upper cartridge 2a so that it does not contact the upper cartridge 30. In addition, this is to ensure that the lid 30 is locked. However, it is necessary to make appropriate adjustments within the movable range of the lid lock member 40.

Next, a second embodiment of the present invention will be described in detail with reference to FIGS. As shown in FIG. 5, the configuration of the lid 30 is the same as that of the first embodiment,
The inner diameter of the coil portion 25c of the lid spring 25 is at least 1.5 times the outer diameter of the support shaft 14 of the upper cartridge 2a.

That is, the coil portion 2 of the lid spring 25
The inner diameter of 5c is larger than that of the conventional lid spring. And a lid spring 2 composed of a torsion coil spring.
5, one leg 25a is supported by the frame 2d of the cartridge case 2a, and the other leg 25b is supported by the concave portion 37 of the lid 30, so that the coil 25c itself is inclined.

As shown in FIG. 6, when the coil portion 25c is tilted, an upward component force Fv is generated in the figure. With this component force Fv, friction loss due to contact between the lid 30 and the upper cartridge 2a can be reduced. In order to surely obtain the component force Fv, a notch or a step which can securely hold the leg 25 b of the lid spring 25 is formed with a concave portion 37 of the lid 30.
And the inner diameter of the lid spring 25 is preferably 1.7 to 3 times the outer diameter of the support shaft 14.

[0028]

As described above, according to the present invention, since the coil portion of the lid spring is formed of a compression spring, when the lid is opened, the reaction force opposing the pressing force of the release lever compresses and operates. Friction loss between the lid and the upper cartridge can be reduced, and when the lid is closed, the reaction force opposing the force applied from the lid lock member works by compressing the coil part as well, reducing the friction loss between the lid and the upper cartridge it can. Therefore, the lid can be smoothly rotated without the lid being stopped in the middle of the rotation operation due to the rotational resistance. Further, since the coil portion of the lid spring is merely made of a compression spring, the cost is not significantly increased.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a magnetic tape cartridge according to a first embodiment of the present invention.

FIG. 2 is a basic mounting structure of the lid according to the first embodiment of the present invention.

FIG. 3 shows a state in which the lid spring and the lid are assembled to a support shaft.

FIG. 4 is a partially enlarged view of the assembled state of the magnetic tape cartridge.

FIG. 5 shows a basic mounting structure of a lid according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a force relationship when a lid spring according to a second embodiment of the present invention is attached to a spindle of an upper cartridge.

FIG. 7 shows a basic mounting structure of a conventional lid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic tape cartridge 2a Upper cartridge 2b Lower cartridge 2d Frame 3 Reel 14 Support shaft 15 Lid spring 15a, 15b Leg 15c Coil part 16 Lid lock spring 26 Opening 30 Lid 33 Projection 40 Lid lock member

Claims (1)

[Claims] 1. A magnetic tape reel which is housed in an upper and lower cartridge and has a magnetic tape wound thereon, and is provided at an opening for drawing out the magnetic tape, and is rotatably mounted on a spindle provided on the upper cartridge. The lid is urged toward the lower cartridge by a lid lock spring, and locks the opening of the lid by engaging with the concave portion of the lower cartridge. When the lid is opened, the lid is pressed toward the upper cartridge by an opening lever. A lid lock member which is disengaged from the concave portion to release the locked state of the lid, and a lid comprising a torsion coil spring mounted on a spindle of the upper cartridge and biasing the lid in a closing direction. A magnetic tape cartridge provided with a spring, wherein the coil portion of the lid spring is formed of a compression spring. Magnetic tape cartridge.