JPS6017105Y2 - Tape removal prevention device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tape detachment prevention device, and more specifically, a core is integrally formed in the center between upper and lower discs (generally referred to as collars), and a magnetic tape is wound around this core. To prevent a tape reel from falling off from the collar of a tape reel when the magnetic tape at a portion wound or about to be wound on the tape reel becomes loose. This invention also relates to a tape removal prevention device that is easy to assemble.

In fact, when a tape wound on such a tape reel loosens, the loosened tape has equal elasticity over the entire circumference, so the tape is The tape bulges out in a circular shape toward the outer periphery of the tape reel, and the tape that bulges out in a circular shape larger than the outer periphery of the tape reel bulges out in a circular shape from the outer periphery of the reel and falls downward, and when the reel is driven, the tape bulges out in a circular shape that is larger than the outer periphery of the tape reel. When it falls into the gap, frictional force is generated due to the thickness of the brim, which can cause the lower edge of the tape to get caught, causing streaks on the tape, stretching it to one side, or wrinkles the tape, which may cause the tape to get stuck to the video head. The touch is bad, there are streaks on the screen,
Not only does it have the disadvantage of not being able to run, getting caught or entangled with some kind of equipment or parts, or in the worst case, the tape being damaged or cut, but it also requires great care and a long time to assemble. However, the disadvantage was that the cost was high due to the increase in the number of parts and man-hours.

The present invention was devised to eliminate such drawbacks, and is capable of preventing the magnetic tape from falling off the periphery of the tape reel, and also assembling the tape reel to a predetermined part of the magnetic tape cassette. At the time, the tape is brought into contact with the tape at a predetermined position between the upper and lower discs of the tape reel by simply aligning the notch of the lower disc of the tape reel with the tape contact part of the upper end of the tape stopper provided on the cassette body side. The object of the present invention is to provide a tape removal prevention device that allows the tape to be easily inserted into the tape stopper and prevents the tape stopper from shifting its position due to vibration or the like.

Therefore, in the present invention, a core is integrally formed in the center between the upper and lower discs, a tape reel is provided to wrap the tape around the core, and the tape reel is placed inside the cassette body. The tape reel is rotatably supported on the cassette main body at multiple locations around the tape reel, and a tape stopper piece is provided integrally with the main body, and the upper and lower discs of the tape reel are attached to the upper end of the tape stopper piece. A plurality of notches are formed in the outer periphery of the lower disc in the tape reel to introduce a plurality of the contact parts simultaneously between the discs. By doing so, the plurality of points on the circumference of the tape that are about to expand circularly toward the outer periphery of the tape reel are restricted by the abutting portion at a position slightly inward of the periphery of the reel, and thus the magnetic tape To provide a tape fall prevention device which prevents the tape from falling off the periphery of the tape reel, which is easy to assemble and takes a short time to assemble, and which prevents the tape fall prevention piece from shifting due to vibration or the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, using an example in which the present invention is applied to a VTR magnetic tape cassette for long-term recording and playback.

FIG. 1 is a schematic cross-sectional view of a VTR magnetic tape cassette for long-term recording and playback equipped with a tape detachment prevention device according to the present invention, and FIG. 2 is a cross-sectional view taken along the line ■-■. 1
2 is a cassette body, and as shown in FIG. 2, this cassette body 1 is made up of a small lower case 2 of a size corresponding to the cassette mounting part of a VTR, and a large upper case 3, which are integrated into one body. A lid 3a is attached to the upper opening of 3.

An opening 7 for pulling out the magnetic tape 6 toward the loading side of the VTR is formed between the pair of guide rolls 4.5 erected in the lower case 2, and a stepped horizontal partition 8 between the lower case 2 and the upper case 3. , 9, the lower horizontal partition 8 has a VT
A pair of rotation mechanisms 10, 11 are provided which fit and bear the drive reel shafts (not shown) of R.

Further, a pair of tape reels 12 and 13 are disposed inside the upper case 3 and are respectively interlocked with the rotation mechanisms 10 and 11.
A large amount of tape 6 is wound around the tape reel 12, 13.

Each tape reel 12, 13 has a driven gear 14, 15.
are integrally formed, and the tape reel 12 and 13 are integrally formed.
is rotatably supported on a bearing 16 at a fixed position in the cassette body 1, that is, in the horizontal partition 8.

The magnetic tape 6 wound around the pair of tape reels 12 and 13 in the upper case 3 is guided to the pair of guide rolls 4 and 5 in the opening part 7 of the lower case 2 by guide members 17 and 18. 19
．． 20.21. 22.23. 24.

A total of four guide members 18, 19, 22, 23 among the guide members 17 to 24 are disposed perpendicularly to the slope of the inclined table 25, and the magnetic tape 6 is attached to the guide member 18 disposed in an inclined manner. , 19, 22, and 23, it is guided between the upper and lower cases 3 and 2.

The rotation mechanism 10.11 also includes the driven gear 14.11.
A driving gear 26, 27 that meshes with VT
The rotation of the rotation mechanism 10.11 by the drive reel shaft R is transmitted from the driving gears 26, 27 to the driven gears 14, 15 to rotate the tape reel 12.13 inside the upper case 3.

The tape reel 12.13 has upper disks 12a, 13a and lower disks 12b, 13 as shown in FIGS. 3 and 4.
A core portion 12c is located in the center between the core portion 12c and the portion b.

13c is integrally formed, and the tape 6 is wound around the core portions 12c and 13C.

Further, the tape reel 12.13 is connected to the lid 3a and the bearing 1.
It is rotatably provided on reel shafts 28 and 29 that stand between the reel shafts 6 and 6.

On the other hand, each of the lower disks 12b and 13 in the upper case 3
As shown in FIGS. 3 and 4, a horizontal support plate 30 extending from the inner wall surface of the case 3 to the vicinity of the disks 12b and 13b is integrally formed with the upper case 3 at a portion approximately at the same height as the upper case 3. ,
A gap 31,32 is formed between the support plate 30 and each lower disk 12b, 13b.

The horizontal support plate 30 is held horizontally by an appropriate number of poles 33 erected on the upper horizontal partition 9.

As clearly shown in FIG. 3, the cassette body 1 at multiple locations around each tape reel 12.13 is provided with tape stopper pieces 34 integrally attached to the tape reel 12.13. Four of each are erected at regular intervals.

That is, a tape stopper piece 34 is integrally formed on the horizontal partition plate 8 and the horizontal support plate 30 around each tape reel 12, 13, and the upper end of each tape stopper piece 34... A tape abutting portion 34a is integrally formed between the upper and lower discs, that is, between the discs 12a and 12b and between the discs 13a and 13b, which extends slightly inward from the outer periphery.

The tape stopper pieces 34 can be molded in one step at the same time as the cassette main body 1.

On the other hand, the lower disk 1 in the tape reel 12.13
A plurality of abutting portions 34a and 2b and 13b have a plurality of abutting portions 34a and
A plurality of notches 35 are formed for simultaneously introducing .

In the case of a 90 degree arrangement, it is sufficient to have 4 locations on each side, for a total of 8 locations, but in Figure 3, there are 4 times as many locations, 16 locations on each side, for a total of 32 locations.
The adjustment time in the circumferential direction is set to 174.

In this embodiment, notches 35, which are slightly larger than the tape contact portion 34a, are formed at equal intervals throughout the outer periphery of each of the lower discs 12b, 13b.

Thus, the tape contact portion 34a and the tape reel 1
The correlation with 2.13 and the notch 35 is set as follows.

That is, as shown in FIGS. 5 and 6, the tape contact portion 3
The height h of the tape reel 4a is smaller than the inner height of the tape reel 12.13 (distance between the lower surface of the upper reels 12a, 13a and the upper surface of the lower reels 13b, 13b) H, and the width 1 of the tape contact portion 34a is a notch. 35, and the penetration distance d of the tape contact portion 34a between the discs is smaller than the depth D of the notch 35, so that the following three relational expressions hold true: .

H>h, L>1. D>d With this configuration, when the tape reels 12 and 13 are assembled and attached to a predetermined portion of the cassette body 1, the tape abutting portion 34a of the plurality of tape stopper pieces 34 that are integrally attached to the cassette body 1, Lower disk 12b of tape reel 12.13.

Align the notches 35 in 13b and remove the tape reel 1.
2. When 13 is moved downward, the abutting portion 34a becomes the notch 35.
Said disks 12a, 12b via.

13a and 13b, and only the portion shown by d in FIG. 6 is the disk 12at and 12b, 13a.

It enters inward from the outer peripheral edge between 13b.

Next, the operation of the tape detachment prevention device constructed as described above will be described.

Now, if the magnetic tape 6 wound around the tape reel 12.13 becomes loose or is about to loosen, the magnetic tape 6 that is about to expand in a circular shape outward from the tape reel 12.13 will become loose in a plurality of circles. At a point on the circumference and slightly inward from the periphery of the reel 12.13, the tape stopper piece 3
4, the abutted portion is prevented from moving in the outer radial direction, and at the same time, the portion not in contact with each tape abutment portion 34a moves radially outward, Moreover, since the tape 6 is connected, it swells in a non-circular manner, and the swollen part has a circular arc shape smaller than the outer periphery of the tape reel 12.13, that is, it protrudes not parallel to the outer periphery of the tape reel 12.13 but at an angle, so as to cross the gap 31.32. This can prevent the tape 6 from falling from the periphery of the lower discs 12b, 13b of the tape reel 12.13 into the gap 31.32.

In particular, in the above embodiment, the tape reel 12.1
Since notches 35 are formed at equal intervals around the entire circumference of the lower disks 12b and 13b of No. 3, when the tape reel 12.13 is attached, the reel 12.13 is slightly bent at a maximum angle of less than 22.5 degrees. Since the notches 35 can be aligned with the tape retaining pieces 34 by a simple operation of rotating the tape by 25 degrees, assembly is extremely quick and easy.

Note that this also applies when the tape reel is removed for repair, although this is less frequent.

However, it goes without saying that only eight cutouts 35 in total may be formed in the lower discs 12b and 13b in accordance with the number and arrangement angle of the tape stopper pieces 34.

As described in detail above, the present invention provides the upper and lower discs 12a, 1
A tape reel 12 in which a core part 12c is integrally formed in the center between 2b and a tape 6 is wound around the core part 12c.
The tape reel 12 is rotatably supported within the cassette body 1, and tape stopper pieces 34 are integrally provided with the cassette body 1 at multiple locations around the tape reel 12. A tape abutting part 34a is formed at the upper end of the tape stopper piece 34, and the tape abutting part 34a slightly enters the outer peripheral edge between the upper and lower discs 12a, 12b of the tape reel 12, while the lower disc 12b of the tape reel 12
A plurality of contact portions 34a are provided on the outer peripheral portion of the disk 12a,
Since a plurality of notches 35 are formed to be introduced simultaneously between the tape reels 12 and 12b, the core parts 12c of the tape reels 12 and 13,
The tape is wound on the reel 13c when the reel 12 or 13 is rotated in the direction of loosening due to the shock during transportation, or when no brake is applied due to tape withdrawal, during each winding and rewinding operation, and when the reel 12 or 13 is rotated in the direction of loosening due to impact during transportation. , when the magnetic tape 6 becomes loose, the tape reel 12.13 has a plurality of tape stopper pieces that allow the magnetic tape 6, which tends to expand outward from the tape reel 12.13, to enter slightly inward from the outer periphery of the reel 12.13. The tape contact portion 34a of the tape 6 can prevent the tape 6 from bulging into a circular shape, thereby preventing the following inconvenience from occurring.

That is, the magnetic tape 6 comes off from the periphery of the reels 12, 13 and the gaps 31, 3 at the side periphery of the lower part of the reel 12.13.
2, the tape 6 is pulled, and the lower edge of the tape 6 is stopped by the frictional force with the side circumference of the brim, causing the tape 6 to be streaked, pushed to one side, or Tape 6 may become wrinkled, or tape 6 may become loose on reel 12.
．． This has the effect of preventing the tape 6 from being caught or entangled with devices or parts, etc. below the tape 13, or from being damaged or cut.

Moreover, since the tape stopper piece 34 is integrally formed with the cassette body 1, there is no need to provide a special part to prevent the tape from falling off, and the number of parts can be reduced. In addition to being able to reduce costs, the tape stopper piece 34 is integrated with the cassette body 1, so even if vibrations or shocks are applied during transportation or handling of the cassette, the tape stopper piece 34 is integrated with the cassette body 1, so there is no possibility of any displacement. As a result, the tape detachment prevention function can be maintained well even during such vibrations and shocks.

Moreover, the lower disc 1 on the tape reel 12.13
The tape reel 12, 13 can be attached to a predetermined part of the cassette body 1 by a simple operation of aligning the notches 35 of 2b and 13b with the tape contact part 34a.
It has various excellent effects such as being extremely easy to assemble, reducing assembly man-hours, and permitting manufacturing errors and assembly errors in parts within a wide range.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view of a VTR magnetic tape cassette for long-term recording and playback equipped with a tape detachment prevention device according to the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3. is the first
A sectional view taken along the line ■-■ in the figure, Figure 4 is IV-IV in Figure 3.
FIG. 5 is a cross-sectional view of a main part taken along the line ■--■ in FIG. 3, and FIG. 6 is a view taken along the line VI-Vl in FIG. 1...Cassette body, 6...Tape,
12, 13... Tape reel, 12a, 13a
...... Upper disk, 12 b, 13 b ---
---Lower disc, 12c, 13C...core, 3
4...Tape stopper piece, 34a...
Tape contact portion, 35...notch.

Claims (1)

[Scope of utility model registration request] A core part 12c is integrally formed in the center between the upper and lower discs 12a and 12b, and a tape reel 12 is provided to wind the tape 6 around the core part 12c.
is rotatably supported in the cassette body 1, and tape drop prevention pieces 34 are integrally provided on the cassette body 1 at multiple locations around the tape reel 12, and the tape drop prevention pieces 34 A tape abutting portion 34a is formed at the upper end of the tape reel 12, and the tape contact portion 34a slightly enters the outer peripheral edge between the upper and lower discs 12a, 12b of the tape reel 12.
A plurality of contact portions 3 are provided on the outer peripheral portion of the lower disk 12b in
4a is simultaneously introduced between the disks 12a and 12b.