JPS6327345Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a tape cassette for a VTR or the like, and more specifically, the invention is provided with a tape reel having a center pin, and this center pin is actuated by a biasing means provided in the cassette. This invention relates to improvements in tape cassettes configured to receive thrust loads.

Background Art and Problems In the tape reel having the center pin described above, the center pin rotates under thrust load, so the center pin is made of a material such as POM (polyoxymethylene), which is hard and has a low coefficient of friction, and is not worn out. It is necessary to mold it with a hard-wearing resin material. For this reason, conventionally, this center pin was molded integrally with the upper flange of the reel, or the material cost was high, so to avoid this, only the center pin was molded.
The method used was to mold it with POM resin and insert it into the upper flange of the reel to fix it.

However, in the method of integrally molding the center pin with the upper flange of the reel, the cost of the resin material is high as described above, resulting in an overall high cost. In addition, POM resin has a high molding shrinkage rate, so it has the disadvantage of low productivity even in terms of maintaining dimensional accuracy.

Furthermore, the method of molding only the center pin as a single item increases the number of parts, and therefore does not necessarily result in cost reduction. In addition, since this center pin is extremely small and lightweight, it is easy for automatic machines to make assembly errors, which reduces productivity. Moreover, since the automatic machine itself has to handle very small parts, it becomes mechanically complex, which is one of the causes of increased costs.

Purpose of the invention This invention was made to eliminate the above-mentioned drawbacks.The purpose is to minimize the use of expensive resin materials such as POM resin, reduce the number of parts, and improve productivity. To provide a tape cassette equipped with a tape reel having a shape.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a tape cassette comprising a tape reel having a center pin and configured such that the center pin receives a thrust load from a biasing means provided within the cassette. The center pin and tape crank part were integrally molded.

By configuring as described above, high-cost resin materials such as POM resin can be used only for the center pin and tape crank part, and the number of parts is reduced, and errors in assembling the center pin do not occur, increasing productivity. This will result in significant cost reductions.

Embodiment An embodiment in which the present invention is applied to a tape cassette for a VTR will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a cassette 1 houses a supply reel 3 and a take-up reel 4 on which a tape 2 is wound.
A center pin 5 is provided respectively. The center pin 5 comes into contact with a reel presser spring 6 provided in the cassette 1, and receives a thrust load from the reel presser spring 6 and is urged downward. Shaking is prevented. When the cassette 1 is installed on the reel stands 7 and 8, both reels 3 and 4 are lifted up slightly against the reel presser spring 6, and both reels are crimped onto the center pin 5 and further onto the reel presser spring 6. The reels 3 and 4 are rotationally driven. Reference numeral 9 denotes a cassette opening/closing lid, which rotates and opens automatically when the cassette 1 is inserted into the VTR.

Next, as shown in FIGS. 3 to 5, each of the reels 3 and 4 is composed of a lower flange 11, an upper flange 12, and a tape clamp piece 13 of integral construction. The lower flange 11 is integral with the hub 14,
ABS (acrylonitrile-butadiene-styrene) or HIP-PS (high impact)
Molded from polystyrene resin. A brake pawl 15 is formed on the outer periphery of the lower flange. Further, a vertical clamp groove 16 into which the tape clamp piece 13 is inserted is formed in a part of the outer periphery of the hub 14, and lock grooves 16a for locking are provided on both sides of the inner surface of this clamp groove. There is. Further, on the upper surface of the hub 14, a horizontal guide groove 17 is formed which is continuous with the vertical clamp groove 16 and faces toward the center of rotation of the hub 14, and a plurality of positioning protrusions 18 are protruded. It is set up.

The upper flange 12 is molded from SAN (styrene-acrylonitrile copolymer) or colorless and transparent GP-PS (general purpose polystyrene) resin, and has multiple through holes for positioning at predetermined positions in the center. 19 and an insertion window 20 into which the integrated tape clamp piece 13 is inserted. Then, insert the protrusion 18 provided on the hub 14 of the lower flange into this through hole 19,
By welding this protrusion 18, the upper flange 12 is fixed to the lower flange 11.

The tape clamp piece 13 is a tape clamp portion 2 that is fitted into the clamp groove 16 of the hub 14.
1 and a connecting piece 22 extending from the upper surface of the tape clamp part 21 in a direction substantially perpendicular thereto, and a center pin 5 having a spherical upper part is provided at a predetermined position at the tip of the connecting piece 22. It is being These are integrally molded from the POM resin, and lock claws 21a are provided protruding from both sides of the clamp portion.

Next, in order to fix the tape 2 to the hub 14 using this tape clamp piece 13, the end of the tape 2 is placed near the clamp groove 16 so as to cover the clamp groove 16 of the hub 14. Then, with this tape 2 sandwiched between the clamp groove 16, the tape clamp piece 13 is inserted in the V direction from the insertion window 20 of the upper clamp 12, and placed between the upper and lower flanges. When pushed in the direction of arrow H, the lock pawl 21a is elastically deformed and this portion is locked into the lock groove 16a.
By engaging with the tape clamp piece 1
3 is locked to the hub 14 together with the tape 2. In this locked state, the center pin 5 is placed approximately at the rotation center of the reel, and the reel pressing spring 6 applies a thrust load to the tape reel 5.
will be configured to receive.

Note that by forming a portion of the guide groove 17 (for example, the tip portion) into a tapered wedge shape, it is possible to prevent the center pin portion from shaking in the vertical direction. Furthermore, the elastic force of the connecting piece 22 can be used to prevent the connecting piece 22 from wobbling by making the connecting piece 22 thinner and slightly inclined downward, or by giving it a curvature.

Effects of the invention As explained above, according to the invention, the center pin and tape clamp part are integrally molded, so the use of expensive resin such as POM resin is only required for the center pin and tape clamp part. Most of the reels are made of low-cost ABS.
Since it can be replaced with resins such as SAN, costs can be significantly reduced.

In addition, since the center pin and tape clamp part are integrally molded, the number of parts is reduced, and there are no problems such as assembly errors of the center pin as in the past, which improves productivity and further improves productivity. Cost reduction can be achieved.

[Brief explanation of the drawing]

The figures show an embodiment in which the present invention is applied to a tape cassette for a VTR.
3 is an exploded perspective view of the tape reel, 4 is an assembled perspective view of the tape reel, and 5
The figure is a view taken along the - line in FIG. 4. In addition, in the symbols used in the drawings, 1... cassette, 3, 4... reel, 5... center pin, 6... reel pressing spring (biasing means), 13...
... Tape clamp piece, 21 ... Tape clamp section.

Claims (1)

[Scope of utility model registration request] In a tape cassette that includes a tape reel having a center pin and is configured such that the center pin receives a thrust load from a biasing means provided within the cassette, the center pin and the tape crank portion are integrally molded. Features a tape cassette.