JPH0140429B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic tape cassette having a rotatable reel hub on which a magnetic tape can be wound.

In recent years, there has been remarkable technological development in making magnetic tape devices such as cassette-type video tape recorders thinner and lower in cost, and there are also increasing demands from the market for devices to be smaller and lighter. . In view of these points, the present invention provides a magnetic tape cassette which has a very simple structure and which makes it possible to reduce the thickness and cost of a magnetic tape device such as a video tape recorder.

FIG. 1 shows a side sectional view of the main parts of a conventional example. In the figure, a reel stand 14 is rotatably fitted loosely into a shaft 12 embedded in a substrate 10 of the magnetic tape device main body, and a hook 16 formed on the upper part of the reel stand 14 is connected to a circle formed on a magnetic tape cassette 18. Through the hole 19, it can be engaged with a pawl 26 of a recess 24 provided in the center of a reel hub 22 located inside the cassette and around which the magnetic tape 20 is wound. A roller 28 for rotationally driving the reel stand 14 is located between the substrate 10 and the magnetic tape cassette 18, is rotatably supported by a shaft 32 installed in a lever 30, and rolls into contact with the outer periphery of the reel stand 14. It is arranged like this. The roller 28 is connected to the relay belt 34 and the board 10
It is rotated by a motor 42 via a relay pulley 38 and a motor belt 40, which are loosely and rotatably fitted onto a shaft 36 installed in the shaft 36. The motor 42 is held on a mounting plate 44 and fixed to the base plate 10 with screws 46 and 48.

In the above configuration, the rotation of the motor 42 is performed by the motor belt 40, the relay pulley 38, and the relay belt 3.
4 to the roller 28. Therefore, the reel stand 14 on which the roller 28 is in rolling contact is rotated. Since the hook 16 of the reel stand 14 and the claw part 26 provided on the reel hub 22 are engaged, the reel stand 14 and the reel hub 22 are connected to the shaft 12.
The magnetic tape 20 is rotated integrally around the reel hub 22 to wind the magnetic tape 20 onto the reel hub 22.

In the structure of the conventional magnetic tape cassette and magnetic tape device as described above, in order to rotationally drive the reel hub 22 within the magnetic tape 18, the hook 1 is
It is necessary to engage the reel base 14 having the reel base 14 with the claw part 26 of the recess 24 of the reel hub 22, and then drive the reel base 14 to rotate the reel hub 22, and the reel base 14 is essential. It was becoming. Therefore, magnetic tape cassette 1
The reel stand 14, roller 28, etc. for rotationally driving the reel hub 22 must be disposed below the magnetic tape device 8, and therefore the thickness h of the magnetic tape device inevitably becomes large.

In addition to the conventional example described above, we have also proposed a structure in which a reel hub driving roller, a relay roller, etc. are provided inside the magnetic tape cassette, and the reel hub is rotatably fitted onto a shaft embedded in the cassette and is rotationally driven via a belt. However, this has resulted in the problem that the structure of the magnetic tape cassette itself is complicated and expensive, and the running cost of the magnetic tape drive system is high.

The present invention aims to solve the above-mentioned conventional drawbacks and provide a magnetic tape cassette that is inexpensive and has a simple structure.Thereby, a magnetic tape device that does not require a reel stand can be made thinner, smaller, and lighter. This has made it possible to achieve this goal. Hereinafter, a detailed explanation will be given based on the embodiment of the present invention shown in FIG.

In FIG. 2, a substrate 5 of a magnetic tape device main body capable of recording signals on a magnetic tape such as a tape recorder or reproducing signals recorded on a magnetic tape is shown.
A drive pulley 56 is rotatably fitted loosely onto a shaft 54 implanted in the shaft 54.
Drive rotary body (drive gear) having teeth 58 on the outer periphery
60 are integrally formed. Further, a pulley 64 on which a belt 62 is hung is also provided above the driving pulley 56. Furthermore, a motor 68 held by a mounting bracket 66 is attached to the board 52 with screws 70 and 72.
It is fixed by. Rotating shaft 74 of motor 68
is provided with a pulley 76 that rotates integrally with the pulley 76, and the pulley 76 and the aforementioned pulley 6 are connected to each other.
4, a belt 62 is hung between the two.

The magnetic tape cassette according to the present invention has the following structure. That is, the magnetic tape 8 is attached to the shaft 78 installed between one main flat plate part 50a and the other main flat plate part 50b of the magnetic tape cassette 50.
A reel hub 82 for winding 0 is loosely fitted in a rotatable manner. Here, among the reel flanges 83 and 84 formed integrally with the reel hub 82, the teeth 86 provided on the outer periphery of the reel flanges 84 have the teeth 58 of the driving rotor 60 attached to the edges of the magnetic tape cassette 50, Specifically, the notch 8 is formed between the side surface portion 50c facing the tooth portion 86 and the main flat plate portion 50b following the side surface portion 50c.
It is designed so that it can be engaged through 8.

As shown in FIG. 2, this notch 88 allows the magnetic tape cassette 50 to be moved in a direction perpendicular to the surface of the main flat plate portion 50b, that is, in a direction perpendicular to the surface of the main flat plate portion 50b, that is, as shown in FIG.
When transferring in the direction from the zero side to the substrate 52, the reel flange 8, in which the drive rotary body 60 having the teeth 58 is disposed inside the outer wall surface of the cassette 50,
It has the minimum necessary size and shape that can mesh with the teeth 86 of No. 4. The notch 88 also allows the magnetic tape cassette 50 to be moved from the right direction to the left direction in FIG. 2 parallel to the surface of the main flat plate portion 50b.
Even when transferring 0, the teeth 5 of the drive rotating body 60
8 and the teeth 86 of the reel flange 84. As described above, since the notch 88 is formed across the side surface 50c facing the teeth 86 and the main flat plate 50b following this, the degree of freedom regarding the transfer direction is increased when the magnetic tape cassette 50 is installed in the apparatus. It is large, and the structure of the cassette transfer means (not shown) is also easy. In addition, since the reel flange 84 and the driving rotary body 60 are coupled by gears, there is no need to press them against each other using elastic force or the like, and no lateral pressure is applied to the shaft 78 via the reel flange 84, so the magnetic tape There is no problem of deforming the cassette 50 or causing uneven rotation. Further, the reel flange 84 is attached to the magnetic tape cassette 5.
Since the reel flange 84 is located inside the magnetic tape cassette 50 rather than the outer wall surface of the reel cassette 50, the user cannot easily turn the reel flange 84 from the outside, so the magnetic tape 80 becomes slack inside the magnetic tape cassette 50. There's no danger of it getting pinched or cut.

Moreover, since the size of the notch 88 is kept to the minimum necessary size, the strength of the magnetic tape cassette 50 is insufficient, and even a weak external force can cause the magnetic tape cassette 5 to
There is no fear that 0 will be destroyed.

Further, since the shape of the notch 88 is simple, the structure of the mold used when molding the magnetic tape cassette 50 with resin, for example, may be extremely simple.

Furthermore, the tooth thickness of the tooth portion 86 of the reel flange 84 is made smaller than the tooth thickness of the tooth portion 58 of the disk 60, so that positioning errors in the gear thickness direction when the cassette is installed and errors in the thickness of the gear itself can be avoided. Since the reel flange 84 is configured to mesh reliably, that is, the tooth thickness of the gear portion 86 of the reel flange 84 is configured to mesh with the gear portion 58, the driving force can be transmitted with high reliability.

Next, the operation of this embodiment will be explained. When the motor 68 rotates in the illustrated state in which the magnetic tape cassette 50 is mounted at a predetermined location on the magnetic tape apparatus main body so that the teeth 86 of the reel flange 84 mesh with the teeth 58 of the drive rotor 60, The rotational force of the motor 68 is transmitted through the pulley 76 and the belt 6.
2. It is transmitted to the drive pulley 56 via the pulley 64. When the drive pulley 56 rotates, the drive rotary body 60 having teeth 58 rotates around the drive pulley 56.
The teeth 58 of the drive rotor 60 mesh with the teeth 86 of the reel flange 84 inside the magnetic tape cassette 50 through the notches 88 of the magnetic tape cassette 50. The rotation of the drive rotary body 60 is transmitted to the reel hub 82 at a reduced speed, and the magnetic tape 80 is wound up. It goes without saying that the above can be implemented not only on the take-up side but also on the reel on the supply side.

As described above, the present invention has a flat plate portion that rotatably supports a reel hub with a reel flange around which a magnetic tape is wound inside the outer wall surface of a cassette.
A toothed portion is formed on the outer periphery of the reel flange of the reel hub, and a notch is provided in a side portion of the cassette that can face the toothed portion and a portion of the flat plate portion continuing therefrom, and the notch is , when the magnetic tape is mounted at a predetermined position of a magnetic tape device for recording signals on the magnetic tape or reproducing signals recorded on the magnetic tape, a drive gear for driving a reel provided on the magnetic tape device is attached to the reel flange. Size that allows meshing with the teeth to transmit rotation,
The reel stand 14 used in a conventional magnetic tape device
(see FIG. 1), and there is no need to incorporate a mechanism for driving the reel hub 82 between the magnetic tape cassette 50 and the substrate 52, so the thickness H of the device can be reduced to h in FIG. It can be significantly smaller compared to
Since a lightweight magnetic tape device can be realized at low cost and the structure of the magnetic tape cassette itself is extremely simple, magnetic tape cassettes can also be supplied at low cost, reducing system running costs. There is no risk of the user inadvertently rotating the reel flange and damaging the magnetic tape, and the rotation can be reliably transmitted to the reel flange without deforming the cassette, etc., and the notch In addition, there is no fear that the strength will be lowered due to this, and the shape of the notch can be simplified and molding is easy, which is an excellent effect.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of the main part of a magnetic tape device using a conventional magnetic tape cassette, and FIG. 2 is a side sectional view of the main part of a magnetic tape device using a magnetic tape cassette according to an embodiment of the present invention. be. 50... Magnetic tape cassette, 50b... Main flat plate part, 50c... Side part, 80... Magnetic tape,
82... Reel hub, 84... Reel flange,
86...teeth part, 88...notch part.

Claims (1)

[Scope of Claims] 1. A flat plate portion rotatably supporting a reel hub with a reel flange around which a magnetic tape is wound inside the outer wall surface of the cassette, and a tooth portion is provided on the outer periphery of the reel flange of the reel hub. At the same time, a notch is provided in a side surface of the cassette that can face the tooth portion and a part of the flat plate portion following the side surface of the cassette,
The notch allows the cassette to be placed in a direction approximately perpendicular to the plane of the flat plate in order to be installed in a predetermined position of a magnetic tape device that records signals on the magnetic tape or reproduces signals recorded on the magnetic tape. A magnetic tape cassette having a size and shape that allows a reel drive drive gear provided on the magnetic tape device to mesh with the teeth of the reel flange to transmit rotation when the magnetic tape cassette is transported. 2. The notch is configured so that when the cassette is transferred in a direction substantially parallel to the surface of the flat plate part, a drive gear for driving the reel provided in the magnetic tape device meshes with the teeth of the reel flange to transmit rotation. 2. A magnetic tape cassette according to claim 1, which has a size and shape that allows for.