JPH0887859A - Tape cartridge - Google Patents

Abstract

PURPOSE: To lessen the load in the rotation while enhancing the smoothness by projecting a roller receiver integrally from the inner face of a cartridge case and forming a protrusion, coming into point contact with the roller receiving face of the roller base, on the end face of a tape guide roller. CONSTITUTION: A roller receiving base 5 is projected integrally from the inner face of a plastic cartridge case 1 in the way of tape running path and a shaft 6 is stood in the center of the flat roller receiving face 5a of the receiving base 5. A tape guide roller 4 is a plastic tube into which the shaft 6 is inserted rotatably to form a protrusion 4b of 0.5-3mm high over the entire circumference of the end face 4a. A shorter protrusion causes adverse effect of the flow and weld mark at the end 4a and a higher protrusion shortens the effective length of tape guide face to cause trouble in the running of tape. This structure reduces frictional resistance between the roller 4 and the receiving base 5 and prevents generation of noise from the tape and powdering thereof through smooth rotation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cartridge provided with a tape guide roller, and more particularly to a tape guide roller provided with measures for improving the rotation performance.

[0002]

2. Description of the Related Art For example, in a beta type tape cartridge shown in FIG. 3, a pair of left and right reels 2 and 2 are housed in a cartridge case 1, and a tape 3 wound on one reel 2 is attached to the cartridge case 1. The tape guide rollers 4 are arranged at several points in the course of running the tape, which are taken out to the front side of the reel and wound on the other reel 2.

There, as shown in FIG. 1, a roller receiving stand 5 is integrally formed on the inner surface of the cartridge case 1, and a shaft 6 made of metal or plastic is erected on the roller receiving surface 5a of the roller receiving stand 5. The tape guide roller 4 is rotatably inserted and supported on the shaft 6 with a slight clearance. This type of roller 4 rotates while the tape 3 is in contact with the outer peripheral surface of the roller 4, and the tape running path is changed without damaging the tape 3 or applying extra tension.

[0004]

Tape guide roller 4
In most cases, they are integrally formed by injection molding.
There is an unavoidable problem that flow marks and weld marks are generated in La4. In the tape cartridge shown in FIG. 3, the roller surface on which the tape 3 is slidably contacted is avoided and the end surface 4a of the roller 4 which does not contribute to tape running has a flow mark or There is a tendency to shift the position where the weld mark is generated. In this case, the problem of tape damage due to the generation of flow marks and weld marks on the tape running surface can be solved, but on the other hand, on the other hand, the end surface 4a which is the rotating surface of the guide roller 4 is solved. Accuracy will deteriorate, and the problem that uniform end surface accuracy cannot be obtained occurs.
The rolling smoothness of the roller is reduced. In particular, the tape guide roller, which requires high rotational accuracy and high-speed rotation, has insufficient accuracy, which causes an increase in the dropout of the tape cartridge.

An object of the present invention is to improve the smoothness of rotation in a tape cartridge provided with a tape guide roller that can be received on a roller pedestal, by providing an improvement between the end surface of the tape guide roller and the roller receiving surface. There is a point to try.

[0006]

A tape cartridge, which is a premise of the present invention, has a roller holder 5 projectingly formed on the inner surface of a cartridge case 1 and a flat roller holder of the roller holder 5 as shown in the figure. The shaft 6 is erected on the surface 5a,
The tape guide roller 4 is rotatably inserted through the shaft 6, and the axial end surface 4a of the tape guide roller 4 is received on the roller receiving surface 5a.

In addition, a protrusion 4b is formed on one of the roller receiving surface 5a and the axial end surface 4a of the tape guide roller 4 so as to make a point contact. The protrusion height of the protrusion is 0.5 to 3 mm.

[0008]

[Function] The protrusion is the axial end surface 4a of the tape guide roller 4.
It works to reduce the frictional resistance on the contact surface between the roller support 5 and the roller support 5.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure of the target tape cartridge is the same as that of the conventional example shown in FIG. In FIG. 1, a roller holder 5 is integrally formed on the inner surface of a plastic cartridge case 1 along the tape running path, and a metal shaft 6 is formed at the center of a flat roller receiving surface 5a of the roller holder 5. Is set up. The shaft 6 may be made of plastic which is integrally erected from the roller pedestal 5.

The tape guide roller 4 is formed of plastic in a cylindrical shape, and is rotatably inserted and supported by the shaft 6 with a slight clearance.

A projection 4b is formed on the end surface 4a of the tape guide roller 4 over the entire circumference of the roller end surface.
The height of this protrusion is 0.5 to 3 mm. This is because when the protrusion height is 0.5 mm or less, the influence of flow mark or weld mark generated on the end surface 4a of the tape guide roller 4 cannot be eliminated, while when it is 3 mm or more, −
This is based on the reason that the effective length of the tape guide roller surface serving as the guide surface of the tape 3 is shortened, which hinders stable tape traveling. Further, in this embodiment, the projections 4b are formed above and below the end surface 4a of the guide roller 4. According to this, when the cartridge is assembled, the directionality of the guide roller 4 is eliminated, so that there is an advantage that the assemblability of the cartridge is improved.

The end surface 4a of the tape guide roller 4 in the axial direction is formed into a smooth surface as usual, and the roller receiving surface 5 of the roller receiving base 5 is formed.
A may be formed with a protrusion that makes point contact with the end surface 4a of the tape card roller 4.

The shape of the protrusion 4b can be arbitrarily changed as long as the object of the present invention can be achieved.

Needless to say, the target tape cartridge is not limited to the illustrated example, but may be similarly applied to, for example, a VHS tape cartridge.

[0015]

According to the present invention, the protrusion 4b is formed so as to make point contact with either the roller receiving surface 5a or the axial end surface 4a of the tape guide roller 4. Therefore, since the frictional resistance at the contact surface between the tape guide roller 4 and the roller pedestal 5 can be reduced, a roller guide with a light load can be realized, and the roller 4 can be provided with smooth rotatability. It is also possible to improve the followability of the tape to the roller 4,
The dropout increase can be reduced. In addition, tape slipping can be prevented, which is also effective in preventing noise and dust during running of the tape.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a plan view of the inside of the tape cartridge.

[Explanation of symbols]

 1 Cartridge Case 4 Tape Guide Roller 4a End Face 4b Projection 5 Roller Holder 5a Roller Bearing Surface 6 Shaft

Claims (2)

[Claims] 1. A roller pedestal 5 is formed so as to project from the inner surface of a cartridge case 1, and a shaft 6 is erected on a flat roller receiving surface 5a of the roller pedestal 5, and a tape guide is provided on the shaft 6. In a tape cartridge in which the roller 4 is rotatably inserted and the axial end surface 4a of the tape guide roller 4 is received on the roller receiving surface 5a, either the roller receiving surface 5a or the axial end surface 4a of the tape guide roller 4 is provided. On the other hand, a tape cartridge characterized in that a protrusion 4b is formed so as to form a point contact. 2. The tape cartridge according to claim 1, wherein the protrusion 4b has a protrusion height of 0.5 to 3 mm.