JPH03171488A - Tape cassette - Google Patents

Abstract

PURPOSE:To reduce cost, to eliminate the need for surface finishing which is highly difficult to apply technically, and to facilitate the inspection of products by forming a tape guide by using specific extremely high molecular weight polyethylene resin and PPS resin. CONSTITUTION:The tape guide is formed by using the extremely high molecular weight polyethylene resin whose molecular weight is 500,000 - 1,000,000, PPS resin, and carbon black. The molecular weight of the extremely high molecular weight polyethylene resin is preferably 500,000 - 1,000,000; when the molecular weight is <=500,000, damage to a tape is large and the friction coefficient tends to increase, but when >=1,000,000, the fluidity of the resin itself becomes inferior and molding becomes difficult. Characteristics become stable when 5 - 40wt.% PPS resin and 1 - 15wt.% carbon black are mixed and the surface resistivity is 10<2> - 10<12>OMEGA. Consequently, the cost is reduced, surface finishing which is highly difficult to apply technically is not necessary, and the inspection of products is facilitated.

Description

[Detailed Description of the Invention] [Field of Application of Sangyo Kita] The present invention relates to a tape force 7 pin I, and in particular to an identification type tape guy 1 for a casseno 1 oop.

[Summary of the Invention] This invention is an inexpensive, technically difficult or highly surface finished product by forming a tape guide using an ultra-high separation star polyethylene resin with a molecular weight of 500,000 to 1,000,000 and PPS resin. L
It is possible to obtain a tape cassette with a tape guide that eliminates the need for injury and simplifies product inspection.

[Prior Art] For example, tape cassettes used in video decks, etc. have fixed type tape guides that come into contact with the magnetic tape to stabilize tape running, that is, guides at both ends of the tape when passing the tape over the front of the tape cassette. A table guide is used. FIG. 4 shows an example of this. In FIG. 4, (1) is the main body case, which is usually made of ABS resin. Inside this is a pair of left and right tape reels (
2) is rotatably installed inside, and the magnetic tape (3) is fed out from one tape rill (2), suspended and guided by the tape guide (4), and then led out to the outside of the front of the main case (1), and the other tape is fed out. It is designed to be wound onto a reel (2).

As mentioned above, the tape guy 1ζ installed in the tape force set 1 is installed so as to be in contact with the back side of the tape (Heath side). (Unexamined Japanese Patent Publication No. 61-11
0388) or metallic ones.

(Problem that the invention attempts to solve) By the way, conventional fixed tape guides for cassette tapes have often been made of metal in terms of friction and wear with the tape and durability, but due to the nature of the material, It was necessary to rely on the method of finishing the end face or cylindrical surface of the guide by machining.This resulted in firstly high costs and secondly the need for technology to improve the accuracy of the surface finish, which caused problems with surface roughness. If the surface is too fine, the tape will tend to stick; if it is too rough, the tape will be easily damaged by friction. Thirdly, if a convex scratch occurs on the surface, the material will be hard. There were drawbacks such as the fact that it caused major damage to the tape, which meant that product inspection was important.

The present invention provides a tape cassette which can eliminate the above-mentioned drawbacks.

[Means to solve the problem]

The tape cassette according to this invention has a molecular weight of 500,000 to 1
The tape guide is formed using 1,000,000 ultra-high molecular weight polyethylene resin and PPS resin.

[Effect]

With this structure, the present invention is inexpensive in terms of cost, eliminates the need for surface finishing which is technically difficult, and simplifies product inspection.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. The most effective means for solving the above-mentioned first drawback of the conventional method is to change the material from metal to resin and create a large-sized Larb guide. However, although various tests have been conducted using various types of tape guides made of tC resin, due to the handicap of fixed tape guides, there is severe friction and wear with the tape, and it has not been possible to obtain an appropriate A material. However, as a result of repeated tests, it has been found that good friction characteristics and quality can be maintained by combining ultra-high molecular weight polyethylene resin, PPS (polyphenylsulfite) resin, and Carhon Brasok.

In this case, the molecular weight of the ultra-high molecular weight polyethylene resin is 5.
A value in the range of 00,000 to 1,000,000 is good, and if it is less than 500,000, the damage to the tape will be large and the coefficient of friction will tend to increase as shown in FIG. On the other hand, if it is more than 1,000,000, the fluidity of the resin itself deteriorates, making it difficult to form the mold, which is not preferable. Here, the blending ratio of PPS resin is 5
-40% by weight Carbon blank blending ratio is 1-15% by weight Surface electrical resistance is 102-10 2Ω
It was found that the range of is characteristically stable.

As an ultra-high molecular weight polyethylene resin, studies have shown that, for example, LUBMER (trade name) manufactured by Mitsui Petrochemical Industries (■) has the best effect. As can be seen in Figure 2, PPS resin is used because it overcomes the problem of ultra-high molecular weight polyethylene resins, which are too soft and have slightly inferior shape accuracy, and has the advantage of being able to be constructed without impairing sliding properties. This is what I did.

Conventionally, polyacecool (polyoxymethylene-POM) has been often used as a sliding resin material, but polyacecool causes large damage to the tape due to friction with the tape and tends to increase dropouts, level fluctuations, etc. In addition, in the case of Boli-Secur, there is a drawback that depending on the material of the tape heath, the coefficient of friction increases rapidly with the number of runs, leading to the tape stopping as shown in FIG. On the other hand, if an ultra-high molecular weight polyethylene resin, a PPS resin, and a carbon blank are combined, the friction coefficient with respect to the number of runs becomes as shown in FIG. 3, and the above-mentioned drawbacks can be overcome.

Even in view of the second and third drawbacks of the conventional guides mentioned above, by using a resin guide, the finish is good, the variation in surface condition is reduced, and product inspection can be simplified. Furthermore, even if there is a convex scratch on the tape guide surface, the damage to the tape can be minimized because the material is soft.

[Effect of the invention] As mentioned above, according to this invention, the molecular weight is 500,000 to 100,000.
Since the tape guide is formed using ultra-high molecular weight polyethylene resin and PPS resin, the cost can be reduced, and surface finishing, which is technically difficult, is not required, and the product quality can be improved. Inspection can be simplified.

[Brief explanation of the drawing]

1 to 3 are diagrams for explaining the present invention, and FIG. 4 is a diagram for explaining the tape guide. (1) is a case body, (2) is a tape reel, (3) is a magnetic tape, and (4) is a tape guide. Agent Hidemori Matsukuma J#: Takuwei

Claims (1)

[Claims] A tape cassette having a tape guide formed using an ultra-high molecular weight polyethylene resin with a molecular weight of 500,000 to 1,000,000 and PPS resin.