JPH0454619Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a tape cartridge characterized by the shape of the tape reel that is installed within the main body case.

[Conventional technology]

FIG. 7 shows a standard specification VHS type video tape cartridge, which has tape reels 4, 4 with flanges on both sides of the inside of the main body case 1, on which the tape 3 is wound.

Conventionally, this type of tape reel 4 has a hub 12 and a lower flange 11 integrally formed as shown in FIG. 8, and it is known that a transparent upper flange 10 is welded and fixed to the upper end surface of the hub 12. There is. This type of tape reel 4 has an inner and outer double wall structure having an inner cylinder wall 15 surrounding the hub hole 14 and an outer cylinder wall 16 around which the tape 3 is wound. It is also known to connect the inner and outer cylindrical walls 15 and 16 with radial ribs 28 for the purpose of improving molding accuracy (as disclosed by Jitsukasho).
Publication No. 59-71248, Publication No. 58-14477, Publication No. 57
-28313 Publication, 59-23259 Publication). To form the rib 28, the mold is attached to the lower flange 1.
It is molded by punching in the opposite direction to step 1.

[Problem that the invention attempts to solve]

However, in the conventional hub structure, the strength of the outer cylinder wall 16 on the lower flange 11 side is sufficient, but the fact that the vertical length of the rib 28 is set shorter than the inner and outer cylinder walls 15 and 16 also has an effect. and upper flange 1
The strength on the 0 side was insufficient, and the cylindricity of the outer cylinder wall 16 deteriorated under the tape winding force, which tended to cause tape deformation and uneven tape winding. In addition, generally, a forming gate is set at the center of the inner wall of the inner end of the hub hole 14, that is, the upper end of the inner cylinder wall 15, but in such a case, in the conventional structure, the outer cylinder wall 16 is formed higher than other parts. There was a disadvantage that it could not be formed accurately.

The present invention focuses on this fact and provides a highly rigid hub 12 that is resistant to deformation and eliminates the strength difference between the upper and lower edges of the outer cylinder wall 16 around which the tape is wound.
The purpose is to prevent tape deformation and uneven tape winding.

Another object of the present invention is to connect the inner cylinder wall 15 to the outer cylinder wall 1.
The objective is to substantially equalize the resin flow rate to the upper and lower edges of the outer cylinder wall 16, and improve the molding accuracy of the outer cylinder wall 16 from this point as well.

[Means to resolve the problem]

In particular, the present invention has a tape reel 4 installed in the main body case 1 as shown in FIGS. 1 and 2.
is composed of a lower flange 11 and a hub 12 integrally molded with plastic on the upper surface of the lower flange 11. The hub 12 has an annular inner cylinder wall 15 surrounding the hub hole 14 and an annular outer cylinder wall around which the tape 3 is wound. 16
On the outer periphery of the inner cylinder wall 15, a square intermediate wall 2 whose center of each side connects to the inner cylinder wall 15 at four places in total.
2 is integrally erected from the lower flange 11, and between the intermediate wall 22 and the outer cylinder wall 16, there is an upper hole 24 with a bottom that opens upward and a lower hole 24 with a bottom that opens downward. The holes 25 are formed alternately in the circumferential direction, and the upper holes 24 connect the flesh wall of the lower flange 11 to the bottom wall 26.
The bottom hole 25 has a ceiling wall 2 that covers the upper end of the hole 25.
7, each hole 24, 25 has an intermediate wall 22 and an outer cylinder wall 1.
It is required that ribs 28 and 29 are formed, respectively, to directly connect the two parts.

[Effect of idea]

According to the present invention, the square intermediate wall 22 is integrally erected from the lower flange 11 to the outer periphery of the inner cylinder wall 15, and the center of each side of the intermediate wall 22 is attached to the inner cylinder wall 15. Connect at 4 locations in total. Furthermore, by providing upper punch holes 24 and lower punch holes 25 alternately in the circumferential direction between the intermediate wall 22 and the outer cylinder wall 16, a wall that stands in the vertical direction of each punch hole 24, 25, The outer cylinder wall 16 is simultaneously supported by the radial walls of the bottom wall 26 and the ceiling wall 27, and each of the holes 24, 2
5, the intermediate wall 22 and the outer cylinder wall 16 are connected by ribs 2.
8 and 29 were connected directly. Therefore, together with the presence of the intermediate wall 22, the strength of the outer cylindrical wall 6 around which the tape 3 is wound can be reliably increased between the upper and lower portions, and a tape reel 4 without tape deformation or tape winding irregularities can be obtained. can.

Furthermore, in the conventional example shown in FIG. 8 in which the inner cylinder wall 15 and the outer cylinder wall 16 are directly connected by ribs 28, when the rotational balance of the tape reel 4 is taken into account, the ribs 28 are necessarily radial, and the ribs 28 are radially shaped. Since the radial length of the rib 28 also increases, the rib 2 on the outer cylinder wall 16
The circumferential connection interval between the ribs 28 and the ribs 8 inevitably becomes large, and the reinforcing function of the ribs 28 becomes insufficient. In contrast, in the present invention, a square intermediate wall 22 is interposed, and the ribs 28 and 29 are formed between the intermediate wall 22 and the outer cylinder wall 16. Since it is not necessary to make the ribs 28 and 29 radial, and the radial length is shortened, the ribs 28 and 29 on the outer cylinder wall 16 have a good rotational balance of the tape reel 4 as a whole.
The connection interval in the circumferential direction can be set as small as desired, and in this respect as well, the outer cylinder wall 16 can be fully reinforced.

Furthermore, the upper hole 24 has a bottom wall 26 which is the flesh wall of the lower flange 11, and the wall that closes the upper end of the lower hole 25 has a ceiling wall 27. A wall 26 and a ceiling wall 27 are continuous with the outer peripheral wall 16. Therefore, even if a gate is set on the inner cylinder wall 15 side as usual, the inner cylinder wall 1
5 toward the outer cylinder wall 16.
The upper and lower edges of the outer cylinder wall 16 can be made almost equal.
This also means that the molding accuracy can be improved.

〔Example〕

FIG. 8 shows the schematic structure of a VHS video tape cartridge.

In the figure, 1 is the main body case. Tape reels 4, 4 on which tape 3 is wound are rotatably disposed on the left and right sides inside the main body case 1, and are positioned over drive shaft insertion holes 2, 2 formed through the bottom wall of the case.
The tape 3 is unwound from the tape reel 4 on the right side, crosses tape loading pockets 5, 5 provided on the front surface of the case, and then is wound onto the tape reel 4 on the left side. 6 is the reel brake,
7 indicates a front lid, and 8 indicates a tape guide.

The present invention is characterized by the shape of the tape reel 4 in such a tape cartridge. Next, a specific example will be described.

[Embodiment 1] FIGS. 1 to 5 show a first embodiment of the present invention, in which each tape reel 4 has upper and lower flanges 10 and 11, and a hub 12 that connects both flanges 10 and 11. It consists of. The lower flange 11 and the hub 12 are integrally formed by injection molding, and only the upper flange 10 is formed separately from a transparent plastic material and later joined together.

The hub 12 protrudes from the upper surface of the lower flange 11 and has an annular inner cylinder wall 15 surrounding the hub hole 14 at its center, and an outer cylinder wall 16 around which the tape 3 is wound around the inner cylinder wall 15 in the radial direction. are formed concentrically. The hub hole 14 opens downward, and the player's drive shaft engages with its inner surface. The hub hole 14 has an annular boss 18 on its outer periphery that is fitted into the drive shaft insertion hole 2 and restricts the radial movement of the tape reel 4 to a certain amount. A plurality of protrusions 19 for ultrasonically welding the upper flange 10 are protruded from the outer surface of the upper end wall of the inner cylinder wall 15. Reference numeral 17 on the lower flange 11 is an engagement tooth for a reel brake.

In the illustrated tape reel 4, the diameter of the outer cylinder wall 16 is set to be about four times the diameter of the inner cylinder wall 15. The outer peripheral surface of the outer cylinder wall 16 is formed into a perfect circle for winding the tape 3, and a clamp groove 21 is provided at one location on the peripheral surface into which a clamp piece 20 that locks and connects the end of the tape 3 is fitted. .

The hub 12 is provided with a structure mainly for compensating the strength of the outer cylinder wall 16 in a region between the inner cylinder wall 15 and the outer cylinder wall 16. First, a square intermediate wall 22 is formed to surround the inner cylinder wall 15.
These intermediate walls 22 are integrated with the inner cylinder wall 15 via a total of four connecting portions 23 connected to the center of each side thereof and the wall of the lower flange 11.
Each side of the intermediate wall 22 and the outer cylinder wall 16 opposite thereto
A total of four bottomed upper holes 24 that open upward are formed between the two. In addition, a fan-shaped bottomed bottom hole 2 that opens downward while being sandwiched between each top hole 24 is provided.
form 5. In other words, the upper extraction hole 24 and the lower extraction hole 25
and are alternately formed in the circumferential direction as shown in FIG.

Specifically, as shown in FIG. 2, in the case of the upper hole 24, the flesh wall of the lower flange 11 is used as the bottom wall 26,
Further, in the case of the lower hole 25, the wall that closes the upper end thereof is used as a ceiling wall 27, and each hole is formed into a bottomed hole. As a result, the upper and lower edges of the outer cylinder wall 16 are alternately connected to a bottom wall 26 and a ceiling wall 27 that extend in the radial direction.

Further, each of the upper and lower holes 24 and 25 has an intermediate wall 2.
Ribs 28 and 29 that directly connect 2 and the outer cylinder wall 16
Form each. Each upper hole 24 is provided with two ribs 28 that equally divide it into three parts, and each lower hole 25 is provided with one rib 29 that equally divides the inside of the hole into two parts. Both ribs 28 and 29 are formed integrally with the bottom wall 26 and the ceiling wall 27, and the vertical length thereof is set to be the same length as the outer cylinder wall 16.

When the hub structure is as described above, the outer cylinder wall 16
is integrated with the wall that partitions the upper and lower holes 24 and 25 and the radial wall of the ceiling wall 27, and maintains high strength that is difficult to deform.

The upper flange 10 is welded and fixed to the hub 12 while being positioned by the projections 19. Incidentally, with the upper flange 10 fixed to the hub 12, the hub 12
There was a maximum gap of 0.5 mm between the upper end surface and the lower surface of the upper flange 10.

[Embodiment 2] Fig. 6 shows a second embodiment of the present invention, in which the number of upper punch holes 24 and lower punch holes 25 is increased, and in particular, the adjacent interval between the bottom wall 26 and the ceiling wall 27 is narrowed. This embodiment differs from the first embodiment in that it is configured as follows.

As described above, the planar shape of the upper and lower holes 24 and 25 can be arbitrarily modified depending on the diameter of the outer cylinder wall 16, the distance from the inner cylinder wall 15, and the like. Preferably, the vertical walls are radially connected to the outer cylinder wall 16, and the radial walls have a high repetition density, which is advantageous for ensuring strength.

Further, the tape reel 4 may be of a single flange type, and in these cases, the flange and the hub 1
2 may be formed separately and then integrally joined by ultrasonic welding, welding, or the like. Of course, the upper flange 10 and the hub 12 may be integrally molded.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is a partially cutaway plan view of a tape reel, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 3 is an exploded perspective view of the tape reel, FIG. 4 is a perspective view of the tape reel in an inverted state, and FIG. 5 is a sectional view taken along the line B--B in FIG. 1. FIG. 6 is a plan view of a hub showing a second embodiment of the present invention. FIG. 7 is a schematic plan view of a tape cartridge to which the present invention is applied. FIG. 8 is a partially cutaway plan view showing a conventional tape reel. 1... Cartridge case, 3... Tape, 4
...Tape reel, 10...Top flange, 11...
...lower flange, 12...hub, 14...hub hole,
15...Inner cylinder wall, 16...Outer cylinder wall, 22...Intermediate wall, 24...Upper hole, 25...Lower hole, 28,2
9...Reinforcement rib.

Claims (1)

[Scope of claim for utility model registration] Tape reel 4 installed inside main body case 1
is composed of a lower flange 11 and a hub 12 integrally molded with plastic on the upper surface of the lower flange 11. The hub 12 has an annular inner cylinder wall 15 surrounding the hub hole 14 and an annular outer cylinder wall 16 around which the tape 3 is wound.
and a square-shaped intermediate wall 2 on the outer periphery of the inner cylinder wall 15, the center of each side of which connects to the inner cylinder wall 15 at four locations in total.
2 is integrally erected from the lower flange 11, and between the intermediate wall 22 and the outer cylinder wall 16, there is an upper hole 24 with a bottom that opens upward and a lower hole 24 with a bottom that opens downward. 25 are formed alternately in the circumferential direction, and the upper hole 24 connects the flesh wall of the lower flange 11 to the bottom wall 26.
The bottom hole 25 has a ceiling wall 2 that covers the upper end of the hole 25.
7, and each hole 24, 25 has an intermediate wall 22 and an outer cylinder wall 1.
6. A tape cartridge characterized in that ribs 28 and 29 are respectively formed to directly connect the tape cartridge.