JPH0261852A - Helical scanning magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To miniaturize the device and to obtain a tape traveling path which does not cause any damage on tape edges even when the tape travels at high speed by disposing only widthwise regulating guides on the inlet side and outlet side of a cylinder, providing slant guides in distant positions from the cylinder and arranging moreover other guides in numbers in intermediate positions between the guides. CONSTITUTION:The step difference correction is not carried out in the vicinity of the cylinder, but is gently performed using the whole widthwise traveling path. In other words, a slant guide is not provided on the inlet and outlet sides of the cylinder respectively, and only requirement is that the incoming tape to the cylinder and the outgoing tape from there are turned at about 90 deg. in direction respectively, so as to form the traveling path extending from the cylinder on the inlet and outlet sides, and the whole path is inclined to make the step difference at both ends approximately zero. To put it concretely, the tape 2 outgoing from a supply reel 3 in a cassette 1 is allowed to reach the slant guide 10 without changing its height, where the tape 2 wound helically around the guide is raised gradually in the traveling direction to reach a guide 9, and at this time, this guide 9 is inclined to come into contact with the tape 2 at right angle to suit its tortion. Afterward, the tape 2 wound around the widthwise regulating guide 8 at about 90 deg. is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tape running path for a helical scan magnetic recording/reproducing device.

[Conventional technology]

Traditionally, National, Technical, and Report voQ25N are used as tape running paths for home-use helical scan VTRs.
A so-called M-shaped tape running path has been widely used, as described as "Tape running system of VH3 system VTR" on page 61-69 of 01'79. In this tape running path, adjacent to the entry and exit sides of the cylinder, there are inclined guides around which the tape is wound in a spiral manner.

A width regulating guide is arranged to adjust the tape height and run the tape along the lead of the cylinder.

[Problem to be solved by the invention]

This M-shaped travel path is a compact travel path and is effective for downsizing the entire device, but since the inclined guide and width regulation guide are placed close to each other, the tape edge can be prevented during high-speed scanning of the tape. It may cause damage.

An object of the present invention is to provide a tape running path that is compact and does not cause damage to the tape even during high-speed tape running.

[Means to solve the problem]

In the present invention, only width regulating guides are arranged on the entrance and exit sides of the cylinder, the inclined guide is arranged at a position away from the cylinder, and other guides are arranged between the inclined guide and the width regulating guide. It is characterized by

[For production]

As a result, since the width regulating guide and the inclined guide are close to each other, the possibility of damage to the tape due to the width regulating guide flange due to unstable running on the inclined guide during high-speed tape running is reduced. Further, in the present invention, since another guide is disposed between the two guides, this guide serves as a buffer for tape running, thereby promoting the above-mentioned effect.

[Embodiments of the invention]

FIG. 2 shows an overall view of a tape running system according to an embodiment of the present invention, and FIG. 1 shows an enlarged view of a portion to which the present invention is applied. In FIG. 2, 1 is a cassette, and 2 is a magnetic tape (hereinafter simply referred to as tape), which comes out from a supply reel 3 in the cassette 1, travels in the direction of the arrow, and is wound onto a take-up reel 4. 5
A cylinder (rotary magnetic head device) has a rotary magnetic head (not shown) that rotates at a constant rotation speed to scan the tape 2. As shown in the figure, the tape 2 is attached to the cylinder 5.
It travels by winding in a spiral shape of 80 degrees.

8 is a width regulating guide arranged on the cylinder entry side, 2° is an impedance roller, and 10 is an inclined guide. 12 is a width regulating guide, 21 is a fixed head, and 14 is an inclined guide. The tape is driven by a capstan 6 and a pinch roller 7. Reference numerals 11 and 15 are roller guides, 17 and 19 are fixed guides on the cassette exit and entry sides, 16 is a fixed guide, and 18 is a tension pin. The tape 2 travels along a travel path as shown in the figure.

As is clear from FIG. 2, the tension pin 18, the entrance roller guide 11, the entrance width regulation guide 8, the exit width regulation guide 12. The exit roller guide 15 and the pinch roller 7 are movable, and these guides are located in the cassette before loading the tape into the cylinder, and are moved during loading to reach the position shown in the figure. , completes the tape running path.

FIG. 1 shows the arrangement of tape guides around a cylinder to which the present invention is applied. The present invention will be explained below with reference to FIG. Since the tape 2 is spirally wound around the cylinder 5, there is a difference in height between the entrance and exit sides of the cylinder.

Since there is no difference in tape height between the input and output sides of the cassette, it is necessary to eliminate this height difference. The problem with the tape running path of a helical scan magnetic recording/reproducing apparatus using a parallel two-reel cassette is to eliminate this level difference and correct the twist. There are two types of torsion; one is that the tape running direction is not parallel to the chassis surface (cassette reference surface), and the other is that the tape surface is not perpendicular to the chassis surface.

In the conventional M-shaped tape running path, the cylinder is tilted in the direction connecting the tape entrance and exit sides until this level difference is corrected, and each inclined guide provided just before and after the cylinder is used to correct the difference in level. Corrects the twist. Here, the slanted guide refers to a tape guide in which the tape is wound diagonally in a spiral shape. Near the exit side, the tape height is regulated in order to make the tape follow the spiral guide (lead). Because it is necessary to arrange width regulating guides close to each other, in the 1M type tape running path, width regulating guides are arranged immediately before and immediately after the inclined guide. As mentioned above, this configuration
This may cause damage to the tape during high-speed running.

The feature of the present invention is that the above-mentioned level difference correction is not performed only in the vicinity of the cylinder, but is performed gently using the entire width direction of the traveling path. In other words, we do not place an inclined guide near the exit side of the cylinder, but simply change the direction of the tape entering the cylinder and the tape exiting the cylinder by approximately 90°, and we A tape running path is formed that extends in the direction (direction), and the entire running path is tilted so that the difference in level at both ends thereof is approximately zero. Since the horizontal length (span) of this running path is long, the overall angle of inclination may be small, and tape twist correction can be performed at both ends of this span, so an inclination guide is provided at a position away from the cylinder. be able to. This will now be explained based on FIG. FIG. 3 is a front view of the running path seen from the cassette side. The broken line is the state before the whole is tilted, and the solid line is the state after it is tilted. Assuming the cylinder is upright on the chassis, the tape exiting the cylinder,
The tape surface of the tape entering the cylinder is perpendicular to the chassis surface. Therefore, if guides are arranged perpendicular to the tape running direction on the inlet and outlet sides of the cylinder and a tape is wrapped around them for about 90 inches, the tape entering the guide or the tape exiting the guide will have a tape surface facing the chassis surface. The direction of travel is now almost parallel to the chassis surface.This is the tape travel path indicated by the broken line in Figure 3.As can be seen from Figure 1, in this travel path, the tape runs on the cylinder entry and exit sides. The level difference cannot be eliminated even if the tape span L is lengthened.Therefore, the tape level difference can be eliminated by tilting the entire running path and making the tape height equal at both ends of the span L, as shown by the solid line in Figure 3. The shaded area is the tape position in this case.The tape twist at both ends of the tape span caused by this can be corrected by making the tape guides 10 and 14 oblique guides (guides around which the tape is wound in a spiral). As is clear from the above explanation, the span L
The length of the inclined guide 10.14 can be set arbitrarily.
It is possible to position it at a sufficient distance from the cylinder. In addition, the longer the span L is, the smaller the overall inclination angle becomes.6 As is clear from the above explanation and FIG. It rises and then falls by winding around the cylinder 5 in a spiral manner. - the cylinder winding is at the same height in the center as at the inclined guide 10; After that, the tape height further decreases, and the width regulation guide 1 on the cylinder exit side
It is lowest at position 2. Further, the tape height increases between the width regulating guide 12 and the exit side inclined guide 14, and the tape height on the exit side of the inclined guide 14 becomes the same as that on the input side of the inclined guide 10. Since the cylinder 5 is inclined left and right, the difference in height of the entire tape running path is reduced. This facilitates the tape loading mechanism and has the effect of eliminating tape damage during loading. The tape running system shown in FIG. 3 has a running path that is symmetrical with the cylinder as the center. This means that the No. t tape runs in exactly the same way whether it runs in the forward direction or in the reverse direction, and is particularly suitable for devices that perform high-speed forward and reverse searches.

In the present invention, as shown in FIG. 1, between the inclined guide 10 and the width regulating guide 8 in FIG.
Guides are inserted between the and the inclined guide 14. This effect will be explained in detail in FIG.

FIG. 4 shows changes in the tape running path when the tape is wound around the guide 9 at different angles. Although FIG. 4 shows only the cylinder inlet side, the same applies to the outlet side since it is symmetrical. FIG. 4 shows an example where the inclination angle of the cylinder and the lead angle of the tape winding around the cylinder are equal (5 degrees). As mentioned above, the condition for cylinder winding is that the tape heights at the center and at the entrance side of the inclined guide 10 are equal. When traveling route A (solid line) has a wrapping angle of 556, traveling route B (broken line) has a wrapping angle of 40
If the angle is 25°, the running route C (-dashed line) is 25°, the running route D (two-dot chain line) is 10°, and the running route E (three-dot chain line) is when there is no guide 9. Traveling route B Add (') to the guide position in C, ('') in C, and (''') in D.
, E are indicated by adding (''').

As is clear from the figure, increasing the wrapping angle around the guide 9 is very effective in reducing the size of the travel path. In particular, the travel route E without the guide 9 is too long to be practical. Various guides can be considered as the guide 9. For example, it may be an impedance roller as shown in FIG. 2, or it may be a fixed head. Due to the presence of this guide 9, fluctuations in running of the tape due to winding around the inclined guide 10 are alleviated, fluctuations at the width regulating guide position are reduced, and the possibility of edge damage of the tape can be reduced.

Figure 1 summarizes what has been said above.

The tape that comes out of the supply reel 3 of the cassette 1 is twisted,
Inclined guide 1 arriving at inclined guide 10 without changing height
As shown in the figure, since the tape 0 is tilted in the running direction, the tape wound spirally around it exits the inclined guide 10, gradually increases in height in the running direction, and reaches the guide 9. The tape is not wound diagonally around the guide 9, but the tape running direction and the guide axis are perpendicular to each other as in a normal roller guide. That is, the guide 9 is inclined so as to be in contact with the twist of the tape at a right angle. The tape leaving the guide 9 reaches the width regulating guide 8. The tape rises to this point.

The width regulating guide is also a roller guide and has a central axis perpendicular to the tape running direction.

As shown in the figure, the tape wrapped around the width regulating guide 8 by about 90 degrees descends because the guide is tilted forward.

If this downward angle is designed to be the same as the lead angle of the cylinder 5, the tape will spirally wrap around the cylinder 5 and descend. The cylinder is inclined in the direction of arrow A and at the center of the winding, ie the point closest to the cassette side, is at the same height on the entry side of the inclined guide 10, ie the height of the tape in the cassette. Since this running system is almost symmetrical left and right, the running path beyond the center of the cylinder is almost the same as that on the entry side. In other words, the tape descends until it reaches the width regulating guide 12, wraps around 90 degrees at a right angle, and then rises and wraps around the guide 13 at a right angle, before reaching the inclined guide 14. . The inclined guide 14 corrects the twist of the tape so that the height of the tape on its output side is the same as the height of the tape in the cassette.

Although the basic travel route has been described in the embodiment above, various variations thereof are conceivable. For example, although the guide 9 is a guide perpendicular to the tape running direction, it is of course possible to use an inclined guide around which the tape is wound diagonally.

Also, although the width regulating guides 8 and 12 are each made into one guide, it is also possible to use two guides to gradually regulate the tape height. Of course, it is also possible to use a guide (fixed guide). Also, although the running path in Figure 1 is symmetrical, it is not necessary to arrange it completely symmetrically on the left and right, and of course it is possible to change it.
For winding No. 2, it is possible to change the angle on the left and right sides, and also change the distance between the guides, the guide diameter, etc. on the left and right sides. In addition to the basic configuration shown in FIG. 1, it is also possible to newly insert another guide if necessary. Furthermore, in FIG. 1, the angle at which the tape is wrapped around the cylinder 5 is a little over 1800 degrees, but it is clear from the above description that the present invention is applicable even if this wrapping angle is larger, for example around 300 degrees. It is. In addition, in the above description of the embodiment, when winding a tape around a cylinder, the tape height at the center, the entrance height of the inclined guide 10, and the exit height of the inclined guide 14, that is, the tape height in the cassette are approximately equal. However, it is not necessary to make them equal, and it is also possible to provide an appropriate level difference. That is, a step can be provided between the tape height at the center of tape winding in the cylinder and the tape height within the cassette. FIG. 5 shows changes in tape height along the running system in this case. The broken line in FIG. 5 shows the change in height when there is no step as described above, and the solid line shows the change in height when there is a step.

【Effect of the invention〕

According to the present invention, even when the tape is small and runs at high speed,
A running route without tape edge damage can be formed. Furthermore, since the running path is approximately symmetrical left and right with the cylinder as the center, stable tape running can be obtained in exactly the same way during normal rotation and reverse rotation. Furthermore, the tape loading mechanism can be simplified since there is only a small change in tape height over the running path.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the arrangement of tape guides around a cylinder according to an embodiment of the present invention, Fig. 2 is a schematic diagram showing the entire tape running path, and Fig. 3 shows the tape running state of the main part of the running path. FIG. 4 is a diagram illustrating the action of a guide placed between the width regulating guide and the inclined guide, and FIG. 5 is an explanatory diagram showing changes in tape height in another embodiment of the present invention. . 1... Cassette, 2... Magnetic tape, 5... Cylinder, 8.12... Width regulation guide, 10.14...
Inclined guide, 9.13... Guide, 20... Impedance roller, 21... Fixed head. f Figure 2; 抎きTHEA S ° し〉7 11/2: 抯 Ｇａｒｔ Ｇｅｒｅ ｄ/θ, 14: J＠4 Call Force ゛ Id 9, /3 Force “Ido No. 2: Hiring and Discharging Qi Dare S' Shirin γ 8, t2: PJfJ-ito.

Claims (1)

[Claims] 1. Width regulating guides are placed close to the cylinder entry and exit sides, respectively, and inclined guides are placed at positions distant from the cylinder on the cylinder entry and exit sides, so that the slope of the inclined guides provided on the cylinder entry side is A helical scan magnetic recording device characterized in that the tape height on the exit side of the inclined guide provided on the entrance side and the cylinder exit side is equalized, and other guides are arranged between the width regulating guide and the inclined guide. playback device.