GB2058718A

GB2058718A - Magnetic Tape Cassette

Info

Publication number: GB2058718A
Application number: GB8029055A
Authority: GB
Original assignee: TDK Corp
Current assignee: TDK Corp
Priority date: 1979-09-09
Filing date: 1980-09-09
Publication date: 1981-04-15
Also published as: NL8004825A; JPS593422Y2; DE3033882A1; JPS5641883U

Abstract

A magnetic tape cassette (1) comprising a guide pole (8) directly contacting a magnetic tape (3) and a guide pole (7) onto which a guide roll (6) directly contacting said magnetic tape (3) is rotatably fitted, at least one of said guide poles (7) and (8) being colored so as to distinguish between the different guide poles. <IMAGE>

Description

SPECIFICATION Magnetic Tape Cassette The present invention relates to a magnetic tape cassette, a particular application being as a video tape cassette.

As shown in Figure 1 of the accompanying drawings, a conventional video tape cassette comprises a casing formed by an upper half case (1) and a lower half case (2) enclosing reels (4) and (5), onto which a magnetic tape (3) is wound, a guide roll (6) which is rotatably fitted onto a guide pole (7) and which is brought into contact with the magnetic tape (3), and a guide pole (8) which is brought into contact with the magnetic tape (3), the guide poles (7) and (8) being placed in the passage of the magnetic tape (3) between the reels (4) and (5).

The magnetic tape (3) is run in contact with the guide roll (6) and the guide pole (8) sequentially.

A tape pad (9) is placed so as to guide the magnetic tape (3) on to the reel (5), bearing against the tape with a predetermined force. The guide poles (7) and (8) are the same size and project from the half cases (1) or (2), one end of each pole being fitted into each of holes (10) or (11) formed on the half case, and the guide roll (6) is rotatably fitted onto the guide pole (7) as shown in Figure 2.

The magnetic tape (3) directly contacts the surface of guide pole (8). It is necessary to process the surface of guide pole (8) as smoothly as possible so as to prevent friction damage of the magnetic tape (3). The guide pole (7) is covered by the guide roll (6), the latter having a suitably smooth surface, with which the magnetic tape (3) is brought into contact. Therefore, guide pole (7) may have a roughly processed surface since guide roll (6) can be smoothly rotated on it. The guide poles (7) and (8) being of substantially the same size, are difficult to distinguish visually. There is therefore a possibility of using a guide pole which should be used as guide pole (7), as guide pole (8) thereby causing damage of the magnetic tape (3).

In order to prevent such an error occurring, guide pole (7) can be processed to provide the smooth surface required for guide pole (8), even though guide pole (7) need not have such a highly smooth surface. This increases the cost remarkably.

It is an objective of the present invention to provide a magnetic tape cassette which is prepared at low cost by achieving a reduction in the cost of guide pole (7) and simultaneously to prevent friction damage of the magnetic tape (3).

The present invention provides a magnetic tape cassette comprising a first guide pole directly contacting a magnetic tape and a second guide pole onto which a guide roll directly contacting with said magnetic tape is rotatably fitted, wherein at least one of said guide poles is colored so as to distinguish between the different guide poles.

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings wherein: Figure 1 is a partially sectioned plan view of a magnetic tape cassette; and Figure 2 is a view illustrating the positioning of the guide poles and guide role within the half case of the magnetic tape cassette.

Referring to Figures 1 and 2, the casing comprises upper half case (1) and lower half case (2). The guide poles (7) and (8) are fitted into the holes (10) and (11) respectively in the half case (2), so as to project from the half case (2). The guide roll (6) is rotatably fitted onto the guide pole (7). The magnetic tape (3) is wound onto the reels (4) and (5) and is guided by a tape pad (9) and brought into contact with the guide roll (6) and the guide pole (8) the latter having a highly processed smooth surface.

At least one of the guide poles (7) and (8), for example, the guide pole (7), is colored so as to distinguish it from guide pole (8). The guide poles (7) and (8) can then be easily distinguished visually, so preventing an error in the assembly, that is, preventing an inadvertent swopping of guide poles (7) and (8).

When such an error in the assembly can be completely prevented, the surface of the guide pole (7) can be relatively rough compared to that of guide pole (8). The cost of processing can hence be remarkably reduced.

Concerning the coloring, all the surface or a part of the surface, such as an end surface, of the guide poles (7) and (8) can be colored in any desired manner, for example, by using a coating of colored paint on the surface of the guide pole (7) or by using a synethetic resin colored with a pigment in the case where the guide poles (7) and (8) are made of a synthetic resin.

As described above, the magnetic tape cassette of the present invention comprises a guide pole (8) directly contacting the magnetic tape (3) and a guide pole (7) onto which a guide roll (6) is rotatably fitted, at least one of the guide poles being colored so as to be easily distinguishable thereby preventing possible friction damage of the magnetic tape (3) caused by an error in the assembly, that is, the inadvertent swapping of the two kinds of guide poles. The reliablility of the magnetic tape cassette can be remarkably increased in this way.

As the accuracy of the surface processing of guide pole (7), which is covered by the guide roll (6) can now be reduced, the cost of processing is reduced accordingly.

Claims

1. A magnetic tape cassette comprising a first guide pole directly contacting a magnetic tape and a second guide pole onto which a guide roll directly contacting with said magnetic tape is rotatably fitted, wherein at least one of said guide poles is colored so as to distinguish between the different guide poles.

2. A magnetic tape cassette according to claim 1 wherein said first guide pole is of substantially the same size as the second guide pole on which

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Magnetic Tape Cassette The present invention relates to a magnetic tape cassette, a particular application being as a video tape cassette. As shown in Figure 1 of the accompanying drawings, a conventional video tape cassette comprises a casing formed by an upper half case (1) and a lower half case (2) enclosing reels (4) and (5), onto which a magnetic tape (3) is wound, a guide roll (6) which is rotatably fitted onto a guide pole (7) and which is brought into contact with the magnetic tape (3), and a guide pole (8) which is brought into contact with the magnetic tape (3), the guide poles (7) and (8) being placed in the passage of the magnetic tape (3) between the reels (4) and (5). The magnetic tape (3) is run in contact with the guide roll (6) and the guide pole (8) sequentially. A tape pad (9) is placed so as to guide the magnetic tape (3) on to the reel (5), bearing against the tape with a predetermined force. The guide poles (7) and (8) are the same size and project from the half cases (1) or (2), one end of each pole being fitted into each of holes (10) or (11) formed on the half case, and the guide roll (6) is rotatably fitted onto the guide pole (7) as shown in Figure 2. The magnetic tape (3) directly contacts the surface of guide pole (8). It is necessary to process the surface of guide pole (8) as smoothly as possible so as to prevent friction damage of the magnetic tape (3). The guide pole (7) is covered by the guide roll (6), the latter having a suitably smooth surface, with which the magnetic tape (3) is brought into contact. Therefore, guide pole (7) may have a roughly processed surface since guide roll (6) can be smoothly rotated on it. The guide poles (7) and (8) being of substantially the same size, are difficult to distinguish visually. There is therefore a possibility of using a guide pole which should be used as guide pole (7), as guide pole (8) thereby causing damage of the magnetic tape (3). In order to prevent such an error occurring, guide pole (7) can be processed to provide the smooth surface required for guide pole (8), even though guide pole (7) need not have such a highly smooth surface. This increases the cost remarkably. It is an objective of the present invention to provide a magnetic tape cassette which is prepared at low cost by achieving a reduction in the cost of guide pole (7) and simultaneously to prevent friction damage of the magnetic tape (3). The present invention provides a magnetic tape cassette comprising a first guide pole directly contacting a magnetic tape and a second guide pole onto which a guide roll directly contacting with said magnetic tape is rotatably fitted, wherein at least one of said guide poles is colored so as to distinguish between the different guide poles. A preferred embodiment of the present invention will now be described with reference to the accompanying drawings wherein: Figure 1 is a partially sectioned plan view of a magnetic tape cassette; and Figure 2 is a view illustrating the positioning of the guide poles and guide role within the half case of the magnetic tape cassette. Referring to Figures 1 and 2, the casing comprises upper half case (1) and lower half case (2). The guide poles (7) and (8) are fitted into the holes (10) and (11) respectively in the half case (2), so as to project from the half case (2). The guide roll (6) is rotatably fitted onto the guide pole (7). The magnetic tape (3) is wound onto the reels (4) and (5) and is guided by a tape pad (9) and brought into contact with the guide roll (6) and the guide pole (8) the latter having a highly processed smooth surface. At least one of the guide poles (7) and (8), for example, the guide pole (7), is colored so as to distinguish it from guide pole (8). The guide poles (7) and (8) can then be easily distinguished visually, so preventing an error in the assembly, that is, preventing an inadvertent swopping of guide poles (7) and (8). When such an error in the assembly can be completely prevented, the surface of the guide pole (7) can be relatively rough compared to that of guide pole (8). The cost of processing can hence be remarkably reduced. Concerning the coloring, all the surface or a part of the surface, such as an end surface, of the guide poles (7) and (8) can be colored in any desired manner, for example, by using a coating of colored paint on the surface of the guide pole (7) or by using a synethetic resin colored with a pigment in the case where the guide poles (7) and (8) are made of a synthetic resin. As described above, the magnetic tape cassette of the present invention comprises a guide pole (8) directly contacting the magnetic tape (3) and a guide pole (7) onto which a guide roll (6) is rotatably fitted, at least one of the guide poles being colored so as to be easily distinguishable thereby preventing possible friction damage of the magnetic tape (3) caused by an error in the assembly, that is, the inadvertent swapping of the two kinds of guide poles. The reliablility of the magnetic tape cassette can be remarkably increased in this way. As the accuracy of the surface processing of guide pole (7), which is covered by the guide roll (6) can now be reduced, the cost of processing is reduced accordingly. Claims

2. A magnetic tape cassette according to claim 1 wherein said first guide pole is of substantially the same size as the second guide pole on which said guide roll is rotatably fitted.

3. A magnetic tape cassette according to claim 1 or claim 2 wherein said guide poles are respectively fitted into holes formed in a half case of the cassette sp as to project inwardly from said half case.

4. A magnetic tape cassette according to claim 1 substantially as herein described with reference to the accompanying drawings.