JPS6334120Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a tape guiding device used in a device such as a video tape recorder that guides a tape in an inclined direction.

[Technical background of the invention]

Video tape recorder (hereinafter referred to as VTR)
In the helical scan method, the first
As shown in FIGS. 2 and 2, the tape 12 drawn out from the cassette 13 must be run around a substantially semicircular circumference of the cylinder 11. cylinder 1
A rotary disk supporting a rotary video head at its circumferential end is coaxially disposed inside the cylinder 1, and as this rotary disk rotates, the rotary video head exposed from between the circumferences of the cylinder is rotated. The tape is scanned diagonally in the width direction of the tape. The tape 12 is placed in a cassette 13
It is pulled out from the cylinder 11 and guided to the tape receiving side of the cylinder 11 by guide poles 14 and 15, and is guided from the cylinder 11 side via a guide pole 16 to a leading pole 17 for return. An erasing head 18 is disposed between the guide poles 14 and 15. tension pole 19
is attached to the top of the tip of the tension arm 20 in an upright manner, and can rotate about the fulcrum 21 in the direction of the arrow A←→B in the figure.
When the tension pole 18 moves in the direction of arrow A in the figure, it tensions the tape 12 and presses the tape against the guide poles 14 and 15 on the cylinder entrance side. Guide poles 22, 23, and 24 forming the return path of the tape running path are provided upright on the ring-shaped loading disk 10. Note that 13a and 13b are guide poles inside the cassette 13.

[Problems with background technology]

By the way, in the case of a VTR, the running path is not formed by the tape being drawn out from the cassette maintaining its horizontal state, but by the tape being pulled out from the cassette, as shown in FIG. It is the lowest in the world. In FIG. 3, the center locus in the width direction of the tape is shown by a chain double-dashed line H.

When such a tape running path is formed,
Especially in the direction changing part of the tape, asymmetrical internal stress occurs in the width direction of the tape with respect to the center of the tape due to twisting, and the entire tape is not in an equilibrium state, causing the tape to shift in the width direction and causing scratches or deformation on the edges of the tape. Something happened. This is particularly dangerous when using thin tape.

[Purpose of invention]

This idea was made in view of the above circumstances, and even if the tape forms a running path that deviates in the width direction, the tape is guided so that internal stress that is asymmetrical in the width direction with respect to the center of the tape does not occur. The purpose of the present invention is to provide a tape guiding device that provides a tape guiding device.

[Summary of the idea]

In this invention, for example, as shown in FIG. 4, in order to set the inclination of the guide post 31 of the tape 12, an intersection line 34 between a plane 32 perpendicular to the tape part 12A and a plane 33 perpendicular to the tape part 12B is used. , the axis of the guide post 31 is set so that it is parallel to the axis of the guide post 31.

[Example of idea]

Examples of this invention will be described below with reference to the drawings. That is, in this invention, as shown in Figure 4,
Guide post 3 at the direction changing part of the tape 12
The slope of 1 with respect to the tape running path is selected as follows. That is, the tape direction changing section 30
, the first surface 32 whose center locus is perpendicular to the tape portion 12A viewed in one direction K.
Set. Next, the tape section 1 seen in the other direction L
A second surface 33 whose center locus is perpendicular to 2B is set. First and second surfaces 32, 33
intersect with each other to form a crossing line 34, and this crossing line 34 and the axis of the guide post 31 are set parallel to each other. By setting the inclination of the guide post 31 in this way, the tape parts 12A, 12
Even if the direction of B is changed and shifted in the width direction, the direction of the tape can be smoothly changed three-dimensionally without creating an asymmetrical internal stress in the width direction with respect to the center of the tape. be able to.

As shown in FIG. 4 described above, the axes of each tape direction changing section are set, and the inclinations of the leading pole 17, guide poles 22, 23, 24, etc. as explained in FIG. 1 are selected. In this case, it is natural to determine the inclination of each axis after loading is completed and the tape is pulled out.

[Effect of idea]

With conventional tape guide devices, the twisting of the tape creates asymmetrical internal stress in the tape width direction with respect to the tape center, which can cause the tape to shift in the width direction while the tape is running. The shift phenomenon occurs with strong stress because the smaller the diameter of the loading ring is, the narrower the tape direction change angle becomes.

Therefore, while the conventional method has imposed restrictions on the miniaturization of devices, the present invention is more effective in miniaturizing devices because the asymmetric internal stress described above does not occur in the tape. Furthermore, conventionally,
The guide posts 22, 23, 24, etc. are simply one pin body, and the provision of rollers has been avoided. This is because conventionally, the asymmetrical internal stress described above was generated in the tape at the tape direction conversion part, which tended to cause the tape to shift in the width direction, so providing a roller would only aggravate the phenomenon of misalignment. This is because it will damage the edges of the tape.
Furthermore, as the size becomes smaller, the tape load increases accordingly. However, if the present invention is used, the tape will not shift in the width direction, so the load on the tape can be further reduced by using rollers, and power savings and equipment downsizing can be easily achieved.

[Brief explanation of the drawing]

1 and 2 are a plan view and a perspective view showing a tape guide device of a video tape recorder, FIG. 3 is an explanatory diagram for explaining the tape running path, and FIG.
The figure is a configuration diagram showing an embodiment of this invention. 12... Tape, 30... Tape direction conversion unit,
31... Guide post, 32, 33... First and second surfaces.

Claims (1)

[Scope of utility model registration request] In a tape guide device that changes the direction of a tape in a direction that shifts the tape in the tape width direction, a first surface that is perpendicular to the width center locus of the tape section when viewed in one direction from the tape direction conversion section is set, and the tape A second surface is set perpendicular to the width center locus of the tape portion when viewed in the other direction, and
A tape guide device having a tape guide shaft having a central axis parallel to a line of intersection formed by the surfaces of the tape guide shaft.