JPS6245Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE PRESENT DISCLOSURE The present invention relates to a tension pole control device for a magnetic recording/reproducing device.

A video tape recorder (hereinafter referred to as a VTR) is designed to have a recording and playback function by loading a cassette tape. In other words,
When a cassette is inserted into a cassette housing of a VTR and the cassette housing is pressed into a predetermined position on the VTR body, the cassette is associated with the reel shaft of the VTR. In this case, the tape in the cassette is
The loading disk automatically pulls it out of the cassette and wraps it around the rotating head, ready for the next operation.

When the tape is wound around the cylinder of the rotary head in this way, in order to prevent the tape from coming loose, the tension lever 40 is usually elastically rotated in the direction of arrow E as shown in FIG. A tension pole 41 provided at the rotating end of this lever presses the tape 10 perpendicularly. 1st
The figure shows a state in which the cassette 9 has been loaded, the loading disk 11 has pulled out the tape inside the cassette 9, and the preparation operation has been completed. In FIG. 1, the loading disk 11 has guide rollers 12, 13, 14 whose inner peripheral edges are supported by guide grooves.
It is rotatably supported by. Furthermore,
A toothed surface is formed on the outer peripheral surface of the loading disk 11, and a gear 15 meshes with the toothed surface.
This gear 15 rotates the loading disk 11 when loading or ejecting a cassette, and its driving force is transmitted from a motor 16. The illustrated state of the loading disk 11 is the state after the cassette 9 has been loaded and the tape 10 of this cassette has been drawn out.

A pinch roller 21 is mounted around the upper surface of the loading disk 11 and is supported by a pinch roller support arm 22, which is rotatable in the direction of arrow C←→D. Furthermore, a guide pole 2 is provided around the upper surface of this loading disk 11.
3, 24, 25, 26, and 27 are installed at appropriate positions so as to stand up toward the top surface.

Next, inside the loading disk 11, a rotary head cylinder 31 is arranged at an eccentric position of the disk. Further, inside the loading disk 11, a capstan 32, a magnetic head 34 for audio control signals, a magnetic head 37 for erasing, a tension lever 40, a tension pole 41, etc. are also arranged. Further, guide poles 33, 35, 36, 38, etc. are arranged before and after the magnetic heads 34, 37, etc. in the tape running direction.

In the above-mentioned VTR, the cassette 9 is disposed at the predetermined position shown in the figure and is used in conjunction with the reel stands 45 and 46. When the play button or the record button is pressed in this state as shown in FIG. 1, the tape is supplied from the reel stand 45 on the supply side and wound up by the reel stand 46 on the winding side. Since a VTR uses a scanning method diagonal to the width direction of the tape, the diagonal track is obtained by mechanical position setting.
Usually, this is done by guiding the tape running path in a spiral manner relative to the cylinder 31.

In addition to recording and playback functions, such VTRs usually have fast-forward and rewind functions.

Particularly when fast forwarding or rewinding, the clutch mechanism or the like is switched so that the tape tension is loosened and the reel stand on the take-up side or the supply side is rotated at high speed. In the case of such fast-forwarding or rewinding, conventional VTRs have the drawback of damaging the tape or causing wave-like deformation at the edge of the tape.

That is, when rewinding in a VTR, the tension lever 40 shown in FIG. 2 is mechanically rotated to rotate the tension pole 41 from the position _P1 to the position _P2 in the figure to perform rewinding. This is to reduce the load on the tape, and has the following meaning.

That is, as explained in FIG. 2, in a VTR, the back tension of the tape is detected in order to apply a constant contact pressure to the video rotating head.
It is devised to apply a brake to the supply side reel stand 45. The tension lever 40 is tensioned in the direction of arrow E in the figure by a spring 42,
Further, one end of a band brake 43 is attached to this tension lever 40. 44 is
It is a driving member of the tension lever 40, and when applying tape tension, the tension pole 41 is controlled to rotate in the direction of the arrow E shown in the figure.
0 is set to be attracted by the force of the spring. Note that 50 is a guide pole. This P ₁
In this state, the force due to the tension of the tape 10 and the spring are in a balanced state. When the tape tension is loosened, the tension lever 40 is rotated by the spring 42 in the direction of arrow E in the figure, and acts to hold the tape tension. At the same time, the tension lever 40 pulls the band brake 43, so the supply side reel stand 4
5 brake force can be increased or decreased.

Therefore, during rewinding or fast forwarding, the tension lever 40 is forcibly moved in the direction of arrow F in the drawing by the driving member 44 of the tension lever 40 _.
The tape is rotated to the position of , reducing the frictional resistance of the tape. In other words, the frictional resistance between the band brake 43 and the supply side reel stand 45 is reduced, and the cylinder 3
This reduces the frictional resistance between No. 1 and the tape.

The tension lever driving means described above has the following disadvantages, which may cause deformation or damage to the tape. In other words, the relationship between the cylinder 31 and the tape is such that the tape is oblique to the cylinder axis as shown in FIG. When rewinding a tape in this relationship, if a change in frictional resistance occurs between the tape, the cylinder, and the tape running path, the tension lever 40 swings in the direction of arrow G←→H shown in FIG. Put it away. In other words,
The rotation of the tension lever 40 is restricted by the drive member 44 in the direction of the arrow E in the figure, but the rotation of the tension lever 40 is restricted by the drive member 44 in the direction of the arrow F in the figure.
This is because it can freely rotate against the force of 2. When the tension lever 40 swings in this way, the third
As shown in the figure, the running path of the tape 10 swings in the vertical direction. When the tape 10 is wound up and down in this manner, it is inevitable that winding unevenness in the width direction of the tape, that is, a stepped winding state, will occur on the reel stand side. Furthermore, at the guide pole part in the middle of the tape running path, the edge of the tape touches the tape guide boss 51 as shown in FIGS. deform or change shape.

This idea was made to deal with the above-mentioned circumstances, and it allows the tape to run safely, prevents deformation and damage to the tape, and also ensures that the tape is wound in a well-organized state with no irregularities. It is an object of the present invention to provide a tension pole control device that is easy to use, and that operates accurately and reliably.

An embodiment of this invention will be described below with reference to the drawings.

6 to 8 show an embodiment of the tension pole control device according to this invention, and 55 is a VTR
56 is a cylinder having a rotating head, and 56 is a loading disk. The tension lever device 57 is rotatably supported at one end by a shaft 58 on the chassis of the VTR. A tension pole 59 is attached to the upper surface of the rotating end of the tension lever device 57. The tension lever device 57 is rotatably movable between the side on which the tension pole 59 is provided and the side closer to the loading disk 56 and the side closer to the cylinder 55. In other words, the tension lever device 57 can be moved to a position as shown in FIG. 8 with its rotational end side about the shaft 58 as a fulcrum. When the tension lever device 57 is in the position shown in FIG.
at the initial point when the cassette is loaded and when the eject operation is completed. That is, when the cassette is installed and the loading disk 56 begins to rotate in the direction of arrow _L2 in the figure, the tension lever device 57 moves the spring 6 in the direction of arrow _M2 in the figure.
1 and rotates to the position shown in FIG. In this case, the tension pole pulls out the tape TP from the cassette.

The tension lever device 57 has a bearing portion 62 (shown in FIG. 7) integrally formed with a spring locking portion 63 that protrudes toward the outer circumference. The spring 61 is attached to this spring locking portion 63.
One end of is locked. Further, a cam lever 64 is integrally formed on the bearing portion 62 of the tension lever device 57, and extends between the lever body and the loading disk, and whose tip extends in substantially the same direction as the tip of the tension lever portion. has been done. At the tip of the cam lever 64, the cam lever 64 and the tension lever device 57 rotate together in the direction of arrow _M1 in the figure.
A locking portion ₆₄₁ is formed facing in the direction of rotation. Next, the cam lever ₆₄₁ and the tension lever device 57 are given rotational force by a spring 61 in the direction of arrow _M2 in the figure. The other end of the spring 61 that applies rotational force to the tension lever device 57 is connected to a first arm 6 provided on a first control member 66 that controls the tension lever.
It is locked at the tip of 8.

The control member 66 has a pivot 67 as its pivot point.
It is rotatably supported by. The rotation fulcrum part is connected to the cylinder 5 by the tension lever device 57.
When the cam lever 64 is rotated toward the 5 side, it is set in the direction in which the cam lever 64 extends. This control member 64 is
The first arm 68 extends in a direction intersecting the lever portion of the tension lever device 57, and the second arm 68 extends in a direction opposite to the cam lever 64.
arm 69 and the loading disk 56
It integrally includes a third arm 70 extending toward the inner circumferential surface near the loading disk 56, and a fourth arm 71 extending toward the outer circumference passing through the lower part of the loading disk 56.

The first control member 66 is set so that its third arm 70 falls into the notch ₅₆₁ of the loading disk 56 in the state shown in FIG. In other words, the first control member 66 is
A biasing force is applied in the direction of arrow _M2 shown in the figure by a spring (not shown). Therefore, the first
By loosening the tension of the spring 61 of the arm 68, the tension lever device 57 can be rotated in the direction of arrow _M1 shown in the figure. (Situation shown in Figure 8) Next, when the cassette is installed in the VTR,
The VTR moves to a preparatory operation, and the loading disk 56 is rotated by the motor in the direction of arrow _L2 in the figure. As a result, the third arm 70 of the first control member 66 rides on the inner circumferential surface of the loading disk 56 and is rotated in the direction of arrow _N1 in the figure. As a result, the spring 6 of the first arm 68
1, the tension lever device 57
is rotated in the direction of arrow _M2 shown in the figure, and shifts to the state shown in FIG. In this case, in the play state or recording state, the force of the spring 61 moves the tension lever device 57 in the direction indicated by the arrow _M2.
I try to rotate in the direction, but tension pole 5
A force acting on the tape tensioner 9 causes the tension lever device 57 to rotate in the direction of arrow _M1 shown in the figure. Therefore, the rotational position of the tension lever device 57 is determined at a position where the force of the spring 61 and the force due to the tape tension are balanced. In the normal playing state or recording state, the first control member 66 is rotated further in the direction of arrow _N1 than in the state shown in FIG. 6, and the cam lever 64 of the tension lever device 57 Second
The spring tension is set so that the balance occurs without contact with the pin ₆₉₁ at the tip of the arm 69.

Next, when the VTR is placed in fast forward or rewind mode, the first control member 66 is controlled to rotate in the direction of arrow _N2 in the figure. This is achieved by slightly moving the play operation interlocking member 75 in the direction of the arrow _Q2 shown in the figure by a member interlocked with the rewind operator or the fast forward operator. As a result, the first control member 66 is rotated in the direction of arrow _N2 in the figure by the self-returning spring, and the tip of the third arm 70 hits the inner circumferential surface of the loading disk 56. At the same time, the pin ₆₉₁ at the tip of the second arm 69 presses the cam lever 64 of the tension lever device 57, causing the tension lever device 57 to rotate in the direction of arrow _M1 shown in the figure. In this case, of course, the spring tension between the first arm 68 and the cam lever 64 is acting, and the state is exactly as shown in FIG. 6. In this case, the rotational position of the tension lever device 57 is set to a position where the tape TP does not come off from the tape guide portion of the guide post 85 provided nearby.

That is, when the VTR is set in the fast forward or rewind state, the rotational position of the tension lever device 57 is locked in the state shown in FIG. 6.
That is, a shaft 80 is provided between the shafts 67 and 58 and protrudes in the same direction as these shafts, and a second control member 81 is rotatably provided on this shaft 80. . This second control member 81
The first arm 82 extends in the direction of the gap between the shaft 67 and the tip of the cam lever 64. The first arm 82 of the second control member 81 extends around the outer periphery of the rotational path of the tip of the cam lever 64. A locking portion 82 1 is formed at the tip of the first arm 82 so as to face the locking portion 64 ₁ of the cam lever 64 and can engage with the locking portion 64 ₁ . In other words, the locking portion ₈₂₁ moves away from the rotation locus of the locking portion ₆₄₁ by rotating in the direction of the arrow O2 shown in the figure, and by moving rotationally in the direction of _the arrow _O1 shown in the figure. It is positioned on the rotation locus of the locking portion ₆₄₁ and can receive it. Next, the second arm 83 of the second control member 81 also extends in the direction of the inner peripheral surface of the loading disk 56. This second control member 81 is biased in the direction of arrow _O1 by a spring (not shown). When the second arm 83 falls into the notch 56 ₂ of the loading disk 56 due to its biasing force, the second control member 81 has a locking portion 82 ₁ of the cam lever 64 . It is in a state where it has been rotated to a position where it can be locked with the locking part ₆₄₁ .

In the state shown in FIG. 6, the second control member 81
is engaged with the cam lever 64, and the tension pole 5
9 restricts rotation in the direction of arrow _N1 shown in the figure. The state shown in FIG. 6 is a state in which the loading disk 56 has completed its preparation operation. When the VTR is ejected and the loading disk is rotationally driven by the motor in the direction of arrow _L1 shown in the figure, the tip of the second arm 83 of the second control member 81 is located at the inner periphery of the loading disk. It will land on the surface. As a result, the second control member 81 is rotated in the direction of arrow _O2 in the figure, and the locking portion ₈₂₁ of the first arm 82 is separated from the engagement position of the locking portion ₆₄₁ of the cam lever 64. . Therefore, when the loading disk 56 is in the state before loading the cassette, that is, when the ejection is completed, the tension lever device 57 has been sufficiently rotated to the state shown in FIG. The tension pole 59 is positioned at the tape draw-out opening of the cassette, making it possible to draw out and store the tape. In other words, at this time, the third arm 70 of the first control member 66 is connected to the notch 56 ₁ of the loading disk 57.
Because it falls down due to the self-returning spring,
The cam lever 64 is connected to the second arm 69 as shown by the arrow.
M It will be pressed in _one direction. In this state, the tape TP is set to such an extent that it does not separate from the tape guide portion of the guide post 85.

One embodiment of the tension pole control device according to this invention is constructed as described above, and in particular,
The position of the tension pole 59 is locked to a fixed position when the VTR is rewinding or fast forwarding. As a result, the tension pole 59 can maintain its set position even if there is a load due to tape friction or the like during rewinding or fast forwarding. Therefore, swinging of the tape in the width direction as explained in FIG. 3 is prevented. This means that the tape running path is stabilized, and the multi-stage winding state on the supply side reel stand etc. is eliminated. When this step-wound condition occurs, friction occurs between the inner surface of the cassette case and the edge of the tape, causing frictional noise during playback, and the tape load fluctuates too much, which can interfere with playback and recording signals. By using this invented device, these drawbacks can be overcome.

Furthermore, the relationship between the guide post 85 and the tape TP is always stable, and the tape trajectory never deviates from the guide post. Further, the tape does not flap around and come off the guide post, and the tape runs smoothly. Therefore, deformation, folding, seaweed-like deformation, etc. of the tape edge can be prevented, which can contribute to maintaining good tape quality and preserving the quality of recorded signals.

Furthermore, according to this invented device, when the loading disk 56 completely rotates to the loading end position, the arm 83 falls into the notch ₅₆₂ , and the cam lever 64 and arm 82 engage with each other. It is configured so that it can be in a synchronous state. Therefore, the arm 82 and the cam lever 6
The timing of forming the engaged state with 4 is selected to be a very logical timing. That is, before the loading disk 56 finishes loading, the tension lever device 57 rotates in the direction of arrow _M2 in the figure and acts to pull out the tape. However, in this case, if there is not enough tape on the reel stand on the supply side, the tension lever device 57 swings to some extent in the directions of arrows M ₁ and M ₂ shown in the figure, and also pulls out the tape from the reel stand on the take-up side. However, it eventually rotates in the direction of arrow _M1 shown in the figure. Therefore, if the second control member 81 fixes the tension lever device 57 in position while the tension lever device 57 is in a transient state as described above, the tape may be damaged. In order to solve this problem, as in the present invention, the arm of the second control member 81 is moved to the cam lever 6 at the same time that the loading disk 57 finishes loading.
It is preferable to plan the timing so as to engage 4.

Further, in this invented device, the inner circumferential surface of the loading disk and its notch are utilized as means for forcibly driving the first and second control members. This has the advantage of making effective use of the rotational movement of the loading disk, eliminating the need for additional accessory parts, and accurately and reliably obtaining the drive timing of each control member.

As explained above, this invention enables safe tape running, prevents deformation and damage to the tape, and allows the tape to be wound in a well-organized state with no unevenness, and the operation is accurate. A reliable tension pole control device can be provided.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a video tape recorder; FIG. 2 is a diagram of a tension lever and its surroundings; FIG. 3 is a plan view and a front view for explaining the relationship between the cylinder and the tape; FIG.
Fig. 5 is an explanatory diagram showing the relationship between the tape and the guide pole caused by the conventional device, Fig. 6 is an explanatory diagram showing the structure of a tension pole control device according to one embodiment of this invention, Fig. 7 is an explanatory diagram showing the structure of the device in Fig. 6 from a different angle, and Fig. 8 is an explanatory diagram showing one operation mode of the device in Fig. 6. 56... loading disk, 57... tension lever device, 61... spring, 64...
...cam lever, 66...first control member, 81...
...second control member.

Claims (1)

[Scope of utility model registration request] a ring-shaped loading disk; a rotary head cylinder disposed at an eccentric position of the disk; and a chassis inside the loading disk rotatably attached to the shaft so as to have a rotating surface of the loading disk; Its rotating end is a tension lever that is set on a part of the upper surface of the periphery of the loading disk and can be rotated between the cassette mounting part (first rotating position) and the cylinder side (second rotating position). a tension pole provided at the rotating end of the tension lever device so as to stand up from the rotating surface; a spring locking portion also provided on the bearing portion of the tension lever device; A locking member protrudes toward the outer circumference of the bearing portion, extends in the same direction as the rotating end portion, and serves to prevent the tension lever device from being rotated to the first rotating position. A cam lever having a stop portion, and a first arm rotatably supported by a shaft on the rotation end side of the tension lever device and protruding from the bearing portion, are attached to the cylinder side. A spring is tensioned between the spring locking portion and the tip of the first arm so as to urge the tension lever device toward the second rotational position, and teeth,
The third arm has a distal end portion that extends toward the cam lever and presses against the cam lever so that the tension lever device rotates toward the first rotational position, and the third arm The fourth arm extends toward the inner circumferential surface of the cam lever, and its tip contacts the inner circumferential surface to restrict the rotational position of the second arm pressing the cam lever. is rotated by a first control member that protrudes outwardly from the loading disk and is associated with the operator, and a shaft that is provided approximately between the first control member and the fulcrum shaft of the tension lever device. The first arm extends along the outer circumference of the rotational trajectory of the tip of the cam lever and has a locking portion corresponding to the locking portion of the cam lever, and the second arm The second arm of the first control member extends toward the inner circumferential surface of the loading disk, and its tip falls into a notch formed at a predetermined position on the inner circumferential surface of the second arm. A tension pole control device comprising: a second control member that engages with the cam lever to restrict rotation of the tension lever device to the first rotation position.