JP2749177B2 - Recording and playback device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a magnetic recording / reproducing apparatus, and more particularly to a tape guide structure suitable for stabilizing tape running near a rush side of a rotary head and preventing tape damage.

[Conventional technology]

Conventionally, in a home VHS type VTR, for example, as described in Japanese Patent Publication No. 58-27580, a tape running path for guiding a tape to a drum by an inclined guide that changes a running plane of the tape is formed. There is. In these schemes,
In the vicinity of two inclined guides arranged on both sides of the drum,
A tape guide that regulates the running height of the tape is disposed next to the inclined guide when viewed from the drum side. To guide you.

[Problems to be solved by the invention]

Among the above-mentioned prior arts, when the two height-regulating tape guides on both sides of the drum are non-rotating, for example, in a system for running a thin, low-rigidity tape with a high tension, the running load is large, and the tension on the drum is high. There is a problem that the tape tension to be detected becomes low and the accuracy is degraded if the value is made constant, and that the tension fluctuation in the tension detecting section is increased up to the drum and becomes large.
On the other hand, when the two height-regulating tape guides rotate, the running tape is deformed by an uneven air film formed between the drum and the tape by the rotating drum, particularly on the entry side of the rotating head. When the tape is wound obliquely with respect to the height-regulated tape guide, the tape runs up or down due to the rotation of the guide, and tape running is not possible. The tape becomes stable or the tape breaks at the flange portion of the tape guide, causing tape damage.
In addition, due to the accuracy error of the tape guide, the same problem occurs because the tape is wound obliquely around the tape guide. Furthermore, when an inclined guide for converting the running plane of the tape is arranged between the drum and the height regulating tape guide,
If you try to increase the tension at the bottom of the tape to follow the drum lead, the difference in span between the upper and lower tapes between the inclined guide and the height-regulating tape guide will cause distortion of the tape, and the tape will be wound diagonally around the tape guide. A similar problem occurs.

An object of the present invention is to prevent the above-mentioned instability of tape running and tape damage.

[Means for solving the problem]

In order to achieve the above object, only on the entry side of the head, the height regulating tape guide disposed near the drum is made non-rotating, and the other tape guide is made to rotate,
A tape running path is formed.

[Action]

When the tape is wound obliquely with respect to the tape guide that has flanges at the top and bottom and regulates the running height of the tape,
The rotation of the guide causes the tape to rise or fall, causing unstable running of the tape, deforming the tape at the flange portion, and causing tape damage. By making the tape guide non-rotating, it is possible to prevent a change in tape running height and tape damage.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

FIG. 2 is a plan view showing a state where a cassette is mounted on the apparatus and before tape loading. FIG. 3 is a plan view showing a state where the tape loading is completed. In FIG. 2, reference numeral 1 denotes a rotating drum device comprising an upper drum which is mounted on a magnetic head 101 (not shown) and rotates, and a fixed lower drum. The take-in reel 4 is incorporated. An opening 8 is provided on the front surface of the cassette 2, and the magnetic tape 7 is stretched in front of the opening 8 by tape guides 5 and 6.

When the cassette 2 is mounted on the apparatus 9, the supply side pull-out guide 10, the supply side tape guide 11, the inclined guide 12, the guide pin 13, the take-up side tape guide 14, and the pinch roller 15 are provided in the opening 8 of the cassette 2. , And the winding-side pull-out guide 16 are inserted. The supply side tape guide 11 and the inclined guide base 18 to which the inclined guide 12 is fixed are mounted on the movable base 17. On the other hand, the take-up side tape guide 14 and the guide pin base 20 to which the guide pin 13 is fixed
It is placed on. These two moving bases 17 and 19
Are guide grooves 21 provided in guide members 21 and 22, respectively.
Move along a and 22a.

In FIG. 3, the position where tape loading is completed is
Fixed members 23, 2 provided near both sides of the rotary drum device 1
4, positioning pins 25 implanted in the moving bases 17 and 19
And 26 and the height determining pins 27 and 28 are engaged and positioned and held. Thus, the tape is wound around the rotary drum device 1.

The supply-side pull-out guide 10 is mounted on an arm 30 that rotates about a shaft 29 and moves to form a supply-side tape traveling path. That is, the magnetic tape 7 that has exited the supply reel 3 is wound around the tension pin 32 via the tape guide 31 and abuts on the full-width erasing head 35 via the supply-side drawer guide 10, the fixed inclined guide 33, and the fixed guide 34. After that, it is guided to the rotary drum device 1 by the supply side tape guide 11 and the inclined guide 12.

The tension pin 32 is implanted at one end of an arm 38 that rotates around a shaft 37 of a potentiometer 36. arm
The other end of 38 is provided with a hole 38a, and a spring 39 is engaged to maintain balance with the tape tension. Thus, the tape tension on the supply side is detected, the torque applied to the supply reel 3 and the take-up reel 4 is controlled, and the tape tension is maintained at a predetermined value.

On the other hand, the pinch roller 15 and the take-up side pull-out guide 16 placed on the arm 40
And moves to form a tape running path on the winding side. That is, the magnetic tape 7 led out from the rotary drum device 1 contacts the partial erase head 43 and the control head 44 via the guide pin 13 and the take-up tape guide 14, and the fixed guide 45, the fixed inclined guide 46, and the fixed After the guide 47, it reaches the capstan 48. The magnetic tape 7 that has exited the capstan 48 reaches the take-up reel 4 via the take-up side draw-out guide 16 and the tape guide 49.

As described above, the tape guide groups 31, 32, 10, 33, 34, 11, 12, 13,
A tape running path is formed by 14, 45, 46, 47, 48, 16, 49, the fixed head groups 35, 43, 44 and the rotary drum device 1, and the capstan 48 presses the magnetic tape 7 together with the pinch roller 15 by pressing. It is clamped and driven at a predetermined speed in a predetermined direction. Also,
The magnetic tape 7 runs by driving the supply reel 3 or the take-up reel 4.

Next, the supply-side tape guide structure will be described. 4th
The figure is a longitudinal sectional view of the supply-side tape guide. Moving base
A tape guide 53 against which the magnetic tape 7 abuts is rotatably mounted on a center shaft 50 implanted in the base 17 via bearings 51 and 52. Above and below the tape guide 53, an upper flange 54 and a lower flange 55 for regulating the running height of the magnetic tape 7 are arranged. The lower flange 55 and the collar 56 are in contact with the inner rings of the bearings 51 and 52, and the tape guide is on the outer ring.
The remaining pressure is applied by the reaction force of the compression spring 57 disposed below the lower flange 55 in contact with the 53. Upper part of center shaft 50
50a is threaded, and adjusts the height of the upper flange 54 and the lower flange 55 by screwing the cap 58. The cap 58 stops rotation by screwing a set screw 59.

Next, the structure of the winding-side tape guide 12 will be described.
FIG. 1 is a longitudinal sectional view of the winding-side tape guide 12. A compression spring 61, a lower flange 62, a tape guide 63, and an upper flange 64 are inserted into a central shaft 60 erected on the moving base 19. The upper portion 60a of the central shaft 60 is threaded, and the height of the upper flange 64 and the lower flange 62 is adjusted by screwing the cap 65. The cap 65 stops rotation by screwing a set screw 66. The tape guide 63 is held between the upper flange 64 and the lower flange 62 by the reaction force of the compression spring 61, and its rotation is stopped. The outer diameter of the intermediate portion 60b of the central shaft 60 is slightly smaller.

FIG. 5 is a schematic view of the vicinity of the drum device 1. For example, as in a D-2 system VTR, during normal recording and reproduction, the magnetic tape 7 moves from the supply side to the take-up side as shown by the arrow A, and the supply-side tape guide 11, the inclined guide 12, the guide pin 13, the take-up Side tape guide 14 and the lead provided on the fixed lower drum 1b
Drive under the regulation of 1c. The rotating upper drum 1a rotates in the direction of arrow B (clockwise) to perform recording and reproduction.

FIG. 6 shows the winding-side tape guide 14 as viewed from the rear of the drum device 1. In an ideal state, the magnetic tape 7 forms one plane between the rotary drum device 1 and the guide pin 13 and between the guide pin 13 and the winding-side tape guide 14, respectively. Also,
The magnetic tape 7 includes a guide pin 13 and a take-up side tape guide 14.
To the drum device 1 in a direction perpendicular to its axis.
, And only the running direction of the magnetic tape 7 is changed on the same plane perpendicular to the magnetic tape 7 until the winding tape guide 14 is pulled out via the guide pin 7. At this time, the magnetic tape 7 is fixed to the lower drum by the upper flange 64.
It is pressed against the lead 1c of 1b, and the traveling height is regulated.
FIG. 6 shows an ideal state. In reality, the magnetic tape 7 does not wind at right angles to the winding side tape guide 14.

FIG. 7 is a view of the drum device 1 as viewed from the axial direction. On the entry side of the rotating head, in this case, on the tape winding side,
By rotating the upper drum 1a in the direction of arrow B, an air film is formed between the rotary drum device 1 and the magnetic tape 7, and the magnetic tape 7a floats from the drum device 1 as shown by a broken line. This air film becomes thinner toward the exit side of the rotary head, in this case, toward the tape supply side, and the floating of the magnetic tape 7a decreases. Therefore, there is a problem that the winding of the magnetic tape with respect to the guide pin 13 is displaced particularly on the entry side of the rotary head having a large flying height.

FIG. 8 is a longitudinal sectional view showing an example of the air film on the rotating head entry side. The magnetic tape 7a floated from the drum device 1 by the air film is deformed out of plane because the thickness of the air film is uneven at some places.
For this reason, the magnetic tape 7 is wound around the guide pin 13 located next to the drum device in a state different from the design, and the next winding side tape guide 14 is also distorted. It will be wound. In such a state, the ninth
As shown in the figure, the magnetic tape 7 is wound obliquely around the axis of the tape guide 14 on the winding side. In the figure, when the magnetic tape 7 is wound up to the left on the winding side tape guide 14 as indicated by the dotted line, the magnetic tape 7 is lowered as indicated by the solid line when the tape guide 63 is rotating. The lower flange 62 is strongly pressed and deformed, and the curl 7b is generated. As a result, tape damage occurs, the tape running height decreases, and the rotary head 101 cannot trace the predetermined position of the magnetic tape 7. When the magnetic tape 7 is wound down to the left on the winding-side tape guide 14, the magnetic tape 7 rises upward, is strongly pressed against the upper flange 64, is deformed, and curls. As a result, tape damage occurs, the tape running height increases, and the rotating head cannot trace a predetermined position of the magnetic tape 7. In this manner, the magnetic tape 7 is obliquely wound around the take-up tape guide 14 not only because of the air film on the side where the rotary head enters but also the guide pin 13 or the take-up tape guide 14.
It can also occur due to an assembly accuracy error in the tilt angle, tilt direction, and position of the motor.

In order to solve these problems, when the tape guide 63 is not rotated, the magnetic tape 7 travels in the longitudinal direction of the tape and does not receive the force of moving in the width direction of the tape. The magnetic tape 7 does not curl due to being pressed.

A similar problem occurs with the supply-side tape guide 11, but
On the supply side, the air film formed by the rotating drum 1a is thinner than the winding side, and there is less problem. Also, as shown in FIG. 10, the tape tension at the position of the tension pin 32 is detected by the potentiometer 36, and the reel motor control circuit controls the winding torque of the supply-side reel motor 67 and the winding-side reel motor 68. In this way, the tape tension is maintained at a predetermined value,
When 11 is not rotated, the running load increases and the tension pin
The rate of increase in the tension from the rotary drum device 1 to the rotary drum device 1 increases, and the fluctuation in tension at the position of the tension pin 32 becomes large by the rotary drum device 1, causing deterioration of the contact of the head tape. Therefore, by configuring the supply-side tape guide to rotate and the winding-side tape guide to non-rotation, an increase in the traveling load to the drum device is suppressed,
In particular, it is possible to prevent a change in the height of the tape running on the winding side, thereby preventing tape damage.

FIG. 11 shows the vicinity of a take-up side tape guide 14 of another embodiment. This is similar to the first embodiment in that the guide pins 13 are eliminated, the magnetic tape 7 that has exited the drum device 1 is directly wound around the winding tape guide 14, and the tape running height is regulated by the flange. It is what was constituted. Also in this case, similarly to the first embodiment, the magnetic tape 7 is wound as shown in FIG. 9 due to the effect of the floating and deformation of the magnetic tape 7 by the air film described in FIGS. Wrap diagonally with respect to the axis of the take-up tape guide. Therefore, even when the magnetic tape 7 retreated from the rotary drum device 1 is directly wound around the winding-side tape guide to regulate the traveling height, only the tape guide 63 on the entry side of the rotary head 101 is made non-rotatable. By doing so, it is possible to suppress an increase in the running load to the drum device, prevent a change in the tape running height on the winding side, and prevent tape damage.

Next, another embodiment will be described with reference to FIGS.
FIG. 12 shows a state in which the tape loading has been completed, and the running system on the tape supply side is the first system shown in FIG.
This is the same as the embodiment. On the tape winding side, the magnetic tape 7 is wound obliquely between the rotary drum device 1 and the winding side tape guide 14 that regulates the running height of the magnetic tape 7, and an inclined plane for changing the running plane is formed. The guide 70 is fixed to the inclined guide base 71, and is arranged on the movable base 19. The magnetic tape 7 derived from the rotating drum device 1
After passing through the inclined guide 70 and the take-up side tape guide 14, it comes into contact with the partial erase head 43b and the control head 44b, and reaches the capstan 48 via the fixed guide 45b, the fixed inclined guide 46b and the fixed guide 47. The magnetic tape 7 that has exited the capstan 48 reaches the take-up reel 4 via the take-up side draw-out guide 16 and the tape guide 49.

 FIG. 13 is a schematic view of the vicinity of the drum device 1.

During normal recording and reproduction, the magnetic tape 7 moves from the supply side to the take-up side as shown by arrow A, the supply-side tape guide 11, the inclined guides 12, 70, the take-up side tape guide 14, and the fixed lower drum 1b.
The vehicle runs while being restricted by the reel 1c provided in the vehicle. The rotating upper drum 1a rotates in the direction of arrow B (clockwise) to perform recording and reproduction.

FIG. 14 shows the winding-side tape guide 14 as viewed from the rear of the drum device 1. In an ideal state, the magnetic tape 7 forms one plane between the rotary drum device 1 and the inclined guide 70 and between the inclined guide 70 and the winding-side tape guide 14, respectively. Also,
The magnetic tape 7 is wound obliquely around the axis of the inclined guide 70, and a running plane (a plane perpendicular to the magnetic tape 7) is converted. Further, the magnetic tape 7 is mounted on the winding side tape guide 14.
On the other hand, the magnetic tape 7 is wound in a direction perpendicular to the axis, and only the running direction of the magnetic tape 7 is changed without changing the running plane.
At this time, the magnetic tape 7 is pressed against the lead 1c of the fixed lower drum 1b by the upper flange 64, and the traveling height is regulated. FIG. 15 is a view of the drum device 1 as viewed from the axial direction.
As described with reference to FIG. 7, a thick air film is formed between the upper drum 1a and the magnetic tape 7a on the rotary drum entry side, and the magnetic tape 7 floats from the drum device 1.

FIG. 16 shows a state in which the magnetic tape 7 is wound around the inclined guide 70. The solid line is the ideal state, and the dotted line is the case where the running position is changed by the air film. In this case,
The angle, direction, etc. of the magnetic tape 7 coming out of the inclined guide 70 change.

FIG. 17 shows the tape span on the rotating head entry side, where 80 is the tangent line between the drum unit 1 and the magnetic tape 7, 81 is the tangent line between the magnetic tape 7 and the inclined guide 70 on the drum unit 1 side, and 82
Is a tangent between the magnetic tape 7 on the tape guide 14 side and the inclined guide 70, and 83 is a tangent between the magnetic tape 7 and the tape guide 14. L ₁ is the distance of the tangent 82 and 83 in the tape lower end, L ₂ is the distance of the tangent 82 and 83 in the tape upper end. In general, L ₁ > L ₂ on the entry side of the rotary head, and L ₁ <L ₂ on the exit side of the rotary head.

In a normal VTR, the tape tension below the magnetic tape 7 is made stronger than that above the magnetic tape 7 because the magnetic tape 7 extends along the lead 1c of the rotating drum 1. Therefore, the distortion increases at the upper end of the tape having a short span, and the tape is wound around the tape guide 14 in a distorted state. Rotating head 101
On the exit side, the upper end of the tape has a longer tape span, so that the distortion is small.

As described above with reference to FIGS. 16 and 17, the magnetic tape 7 is obliquely wound around the winding-side tape guide 14 in FIG. In this case as well, as in the case described in FIG. 9, by making the tape guide 63 non-rotating, it is possible to prevent a change in the running height of the magnetic tape 7 and to prevent curl 7b and tape damage. .

FIG. 9 shows a fourth embodiment, in which the drum device 1 in the third embodiment has a fixed upper drum 1d and a fixed lower drum 1d.
A fourth embodiment is shown in which a rotary head 102 is configured to rotate in a gap between a fixed drum 1d and a fixed lower drum 1b. In this case, the thick air film as shown in FIG. 15 is not formed, but the tape has the inclined guide 70, so that the tape span difference between the inclined guide 70 and the take-up side tape guide 14 as shown in FIG. To have a magnetic tape 7
Is wound around the winding-side tape guide 14 with distortion. Therefore, also in this case, by making the tape guide 63 non-rotating, it is possible to prevent a change in the tape running height and to prevent curling and tape damage.

FIG. 20 is a schematic diagram of the vicinity of a drum device in a VHS system VTR. During normal recording and reproduction, the magnetic tape 7 moves from the supply side to the take-up side as shown by the arrow C. The supply-side tape guide 90, the inclined guides 91 and 92, the take-up side tape guide 93, and the fixed lower drum
The vehicle travels under the control of the lead 1c provided on 1b. The rotating upper drum 1a rotates in the direction of arrow D (counterclockwise) to perform recording and reproduction.

In this case, the entry side of the rotary head is the tape supply side, and the air film formed by the rotation of the rotating upper drum 1a is thicker on the supply side and thinner on the winding side. Therefore,
In such a case, only the supply-side tape guide 70 is non-rotating, and the winding-side tape guide 73 is configured to rotate, thereby stabilizing tape running on the rotating head entry side, and using the flange of the supply-side tape guide 90. This has the effect of preventing tape damage.

Note that, as described in the first embodiment, the inclined guide 91 can be constituted by a guide pin parallel to the tape guide 90, and as shown in the fourth embodiment, a fixed upper drum device is mounted. However, if the rotating direction of the rotary head is the direction of arrow D, the tape guide 90 on the head entry side, that is, the supply side is not rotated, thereby stabilizing the tape running and preventing tape damage.

〔The invention's effect〕

According to the present invention, particularly the deviation of the magnetic tape running path due to the air film formed on the entry side of the rotary head, the difference in the vertical span of the tape between the inclined guide and the tape guide,
Prevents curling of tape guides with flanges caused by deviations in the running path due to guide precision errors,
Since fluctuations in the running height can be prevented, tape damage can be prevented, and stable tape running can be obtained.

[Brief description of the drawings]

FIGS. 1 to 10 show a first embodiment of the present invention.
FIG. 1 is a longitudinal sectional view of a tape guide on a tape winding side, and FIG.
Figures 3 and 3 are plan views of the apparatus, Fig. 4 is a longitudinal sectional view of a tape guide on the tape supply side, Fig. 5 is a schematic view showing the rotation of the drum and the running direction of the tape, and Fig. 6 is the winding side. FIG. 7 is a side view showing the vicinity of the tape guide, FIG. 7 is a plan view showing the floating of the tape by the air film, FIG.
9 is a side view showing the tape running near the take-up side tape guide, FIG. 10 is a schematic view showing a tape tension control mechanism, and FIG. 11 is a side view showing the vicinity of the take-up side tape guide of the second embodiment. FIG. 12 to FIG. 18 show a third embodiment.
FIG. 12 is a plan view of the apparatus, FIG. 13 is a schematic view showing the rotation of the drum and the running direction of the tape, FIG. 14 is a side view of the vicinity of the winding-side tape guide, and FIG. FIG. 16 is a side view showing the winding of the tape on the inclined guide, FIG. 17 is a schematic diagram showing the tape span on the winding side, and FIG. 18 is a view showing the tape running near the tape guide on the winding side. FIG. 19 is a side view showing the vicinity of a take-up side tape guide of the fourth embodiment, and FIG. 20 is a schematic view showing the rotation of the drum and the tape running direction of the embodiment of another embodiment. 1 ... drum device, 1a ... rotating upper drum, 1b ... fixed lower drum, 1d ... fixed upper drum, 11 ... supply side tape guide, 12 ... inclined guide, 14 ... winding side tape guide, 32 ... tension pin, 36 ... potentiometer, 62 ... lower flange, 63 ... tape guide, 64 ... upper flange, 70 ... inclined guide, 101 ... rotating head.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinro Inui 2--15-12 Nishi-Shimbashi, Minato-ku, Tokyo Hitachi, Ltd. Home Appliance Division Hi-Vision Strategic Development Division

Claims (4)

(57) [Claims] A helical scan type recording / reproducing apparatus for recording / reproducing a tape by guiding a tape obliquely around a drum device at a predetermined angle by a tape guide and forming a predetermined tape running path. The tape guide has a flange capable of regulating a running height of the tape in the width direction, and is arranged near both sides of the drum device when viewed along the tape running path, and the rotation of the drum device The recording / reproducing apparatus according to claim 1, wherein the tape guide disposed on the entry side of the head has a non-rotating structure, and the tape guide disposed on the exit side of the rotating head has a rotating structure. 2. The recording / reproducing apparatus according to claim 1, wherein the drum device has a configuration in which an upper drum on which the rotary head is mounted rotates. 3. The drum device according to claim 1, wherein the upper drum and the lower drum are non-rotating, and the rotary head rotates in a gap between the upper drum and the lower drum. 2. The recording / reproducing apparatus according to 1. 4. The tape guide according to claim 1, wherein an inclined guide for changing a running plane of the tape is arranged between the drum device and the tape guide as viewed along the tape running path. The recording / reproducing apparatus according to claim 3.