JPH0614296Y2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a magnetic recording / reproducing apparatus having a back tension mechanism for stabilizing the running of a tape.

[Prior Art] Conventionally, in order to run a magnetic tape in close contact with a magnetic head, a magnetic field having a back tension mechanism that gives a tensile force (back tension) to the feeding side of the magnetic tape in a direction opposite to the traveling direction of the magnetic tape. A recording / reproducing device is known.

In such a back tension mechanism, the back tension is usually applied to the magnetic tape by providing a one-point pressure bonding type brake control means on the supply reel side.

[Problems to be Solved by the Invention] However, in the case where only one supply reel, which is one of the magnetic tape running mechanisms composed of the supply reel and the take-up reel, is provided with the brake control means by a single-point crimping type that applies back tension. However, there is a problem that the back tension is not stable because the back tension applied varies due to the eccentricity of the reel shaft and the change of the friction coefficient due to the change of the winding diameter.

Also, in a system in which the magnetic tape is wound around the rotary head drum and rewound, and the signal recorded on the magnetic tape is traced by the rotary head drum, the brake control means by the single-point crimp type provided only on the supply reel is used. There is also a problem that the tape tension is insufficiently stable when the back tension is applied.

This invention was made in view of the above problems,
The purpose is that the applied back tension does not change due to the change of the friction coefficient due to the eccentricity of the reel shaft or the change of the winding diameter, and further, the magnetic tape is wound around the rotary head drum while being wound. It is an object of the present invention to provide a magnetic recording / reproducing apparatus capable of stabilizing the tape tension even in the case of a system in which the signal is recorded back on the magnetic tape by the rotating head drum.

[Means for Solving the Problems] In order to achieve the above object, a magnetic recording / reproducing apparatus according to the present invention runs a magnetic tape between a supply reel and a take-up reel via a magnetic head, and the magnetic head. In a magnetic recording / reproducing apparatus for recording or reproducing information on the magnetic tape via the magnetic tape, one end is fixed to a tension arm for tape stable running and the other end is fixed to a first lever and mounted on the supply reel. The first line,
A first member for fixing one end to the tension arm for tape stable running and the other end to a second lever and for locking the second linear member mounted on the winding reel and the first lever stepwise. It has a stop portion and a second locking portion for locking the second lever in a stepwise manner, and by sliding one of them, the second lever is moved so that the second linear shape is aligned with the supply reel shaft. When a back tension is applied, the first lever is moved together with the back tension so that the tension applied to the take-up reel shaft by the first linear member is relaxed, and the back tension is slid to the other side. A fast-forward state in which the back tension applied to the supply reel shaft is relaxed, a stop state in which a braking force is applied to the take-up reel shaft and the supply reel shaft, and a back tension in the take-up reel shaft. And a slide member for controlling the rotation of the supply reel and the rotation of the take-up reel so as to sequentially switch to the rewinding state, and the first wire in the direction in which the first linear line gives a back tension to the take-up reel. First urging means for urging the lever; second urging means for urging the second lever in a direction in which the second linear line gives back tension to the supply reel; the first linear line and the The second linear member is provided with an arm urging means for urging the tape stable running tension arm in a direction in which the supply reel and the take-up reel are prevented from rotating.

[Operation] In the magnetic recording / reproducing apparatus according to the present invention, the slide member for controlling the rotation of the take-up reel or the supply reel selectively performs the brake control of the take-up reel or the supply reel to run the magnetic tape. It is possible to apply a constant back tension according to the state, and since it is possible to perform brake control of the take-up reel during rewinding, it is possible to stabilize the tape tension.

[Embodiment] An embodiment of the magnetic recording / reproducing apparatus according to the present invention will be described below with reference to the drawings.

In FIGS. 1 to 5, 1 is a chassis forming the main body of a magnetic recording / reproducing apparatus, 2 is a cassette, 3 is a take-up reel shaft, 4 is a supply reel shaft, and 5 is a magnetic tape installed in the cassette 2. is there. The cassette 2 is fitted into the chassis 1 via a take-up reel shaft 3 and a supply reel shaft 4, which are respectively supported by a take-up reel (not shown) and a supply reel (not shown). The take-up reel shaft 3 and the supply reel shaft 4 are rotationally driven by a driving unit (not shown).

The magnetic recording / reproducing apparatus runs a magnetic tape 5 between a supply reel and a take-up reel via a magnetic head (not shown) incorporated in a rotary head drum 10 which will be described later, and magnetically transmits information via the magnetic head. It can be recorded on the tape 5 or reproduced from the magnetic tape 5.

The magnetic tape 5 wound around the supply reel is pulled out from the cassette 2, and is fixed post 6, tension post 7, guide roller 8, tilt post 9, rotary head drum 10, tilt post 11, guide roller 12, and fixed. After passing through post 13, pinch roller 14 and capstan 1
The pinch roller 14 and the capstan 15 are driven by the pinch roller 5 and the capstan 15, and are wound around the take-up reel through the fixed guide 16.

A tape stable running tension arm (tension arm) 17 provided with a tension post 7 is rotatably supported about a pivot 18, and a spring 19 is provided.
It is urged to rotate counterclockwise by (arm urging means).

In addition, the tension arm 17 has a thread 20 (first line).
One end of each of the yarns and the yarn 21 (second line) is connected and fixed, and the position of the tension arm 17 is regulated by the balance between the spring 19 and the tensions of the yarns 20 and 21.

Thread 20 having one end tied to the tension arm 17
Is wound around the take-up reel shaft 3 via the roller 22 from the side of a lever 23, which will be described later, and is wound about one revolution in the clockwise direction, and the other end is tied and fixed to the lever 23.

The lever 23 (first lever) has a substantially L shape in which a pivot 24 is provided at a projecting end on the rear surface of the lower piece and a pin 26 is provided at a bent portion.
It is formed in a letter shape, and is attached so as to be rotatable around a pivot 24 engaged with a slide groove 35 of a slide lever 27 described later.

Thread 21 with one end tied to tension arm 17
Is wound around the supply reel shaft 4 from the side of a lever 29, which will be described later, and is wound around the supply reel shaft 4 in the counterclockwise direction by one rotation, and the other end is tied and fixed to the lever 29.

The lever 29 (second lever) has a substantially L shape in which a pivot 31 is provided at a projecting end on the back surface of the lower piece and a pin 33 is provided at a bent portion.
It is formed in a character shape, and is attached so as to be rotatable around a pivot 31 engaged with a slide groove 36 of a slide lever 27 described later.

The slide lever 27 (slide member) has, on the right side, a slide groove 35 and a pin 2 for locking the pivot shaft 24 of the lever 23.
6 has a locking groove 28 (first locking portion), and on the left side, a slide groove 36 locking the pivot 31 of the lever 29 and a locking groove 34 locking the pin 33 (second locking member). It is formed in a long plate shape having a stop).

The slide grooves 35 and 36 are formed horizontally in the longitudinal direction of the slide lever 27. The locking groove 28 is formed in a step shape that connects an upper flat portion 28a on the left upper side and a lower flat portion 28b on the lower right side by a slope portion, and the locking groove 34 is formed on the lower left side. The lower flat portion 34a and the upper flat portion 34b on the right side are connected by a slope portion, and a middle flat portion 34c is formed in the middle of the slope portion in a stepped shape.

Therefore, the lever 23 is locked in the locking groove 28 in the upper and lower two steps, and the lever 29 is locked in the locking groove 34 in the upper, lower, middle three steps, respectively.

The slide lever 27 is driven by a driving means (not shown), and is slid in the left-right direction while being guided by the pivot shaft 24 locked in the slide groove 35 and the pivot shaft 31 locked in the slide groove 36.

The lever 23 is biased by a spring 25 (first biasing means) in a counterclockwise direction in which the yarn 20 applies back tension to the take-up reel shaft 3, but the pin 26 is Since it engages with the locking groove 28, it cannot rotate at the engaging position.

In addition, the lever 29 includes a spring 32 (second biasing means).
Due to this, the yarn 21 is rotationally urged in the clockwise direction, which is a direction that gives back tension to the supply reel shaft 4, but the pin 33 is engaged with the locking groove 34, and therefore cannot rotate at the engagement position. Is in a state.

Therefore, the slide lever 27 controls the rotation of the supply reel shaft 4 via the thread 20 in accordance with each locking position of the lever 23, and the winding reel shaft via the thread 21 in accordance with each locking position of the lever 29. The rotation of 3 can be controlled.

That is, by sliding the slide lever 27 to one side, the lever 29 is moved so that the yarn 21 gives back tension to the supply reel shaft 4 and the lever 2
3 is moved to a reproduction state in which the tension applied to the take-up reel shaft 3 is relaxed, and by sliding from this reproduction state to the other, the back-tension imparted to the supply reel shaft 4 is relaxed in the fast-forward state. Controlling the rotation of the supply reel and the rotation of the take-up reel in the stopped state in which the braking force is applied to the take-up reel shaft 3 and the supply reel shaft 4 and the rewinding state in which the back tension is applied to the take-up reel shaft 3. And can be switched sequentially.

The counterclockwise direction in which the spring 19 urges the tension arm 17 to rotate is a direction in which the yarn 20 and the yarn 21 prevent the supply reel shaft 4 and the take-up reel shaft 3 from rotating, and further, the spring 19 is It has a stronger urging force than the urging force of the spring 32 or the combined urging force of the spring 25 and the spring 32.

Next, the operation of the magnetic recording / reproducing apparatus having the above configuration will be described.

First, the position of the slide lever 27 in FIG.
In this position, the pin 33 reaches the left end of the locking groove 34 and is located in the lower flat portion 34a, so that the lever 29 is rotated clockwise about the pivot 31 as much as possible. It has been rotated and stopped.

At this time, the yarn 21 pulls the tension arm 17 toward the supply reel shaft 4 side against the urging force of the spring 19, and at the same time, the rotational moment of the tension post 7 due to the driving tension of the magnetic tape 5 acts to generate the tension. Changed,
The friction between the yarn 21 and the supply reel shaft 4 gives back tension to the supply reel shaft 4.

On the other hand, in the lever 23, the pin 26 reaches the left end of the locking groove 28 and is located in the upper flat portion 28a, so that the lever 23 is rotated clockwise about the pivot 24 as much as possible and is stopped. Therefore, the yarn 20 is in a slackened state and does not serve as a load on the take-up reel shaft 3.

That is, the slide lever 27 is located on the rightmost side,
The lever 23 is in a state in which the yarn 20 is loosely wound around the take-up reel shaft 3 to relieve the tension with respect to the take-up reel shaft 3, and at the same time, the lever 29 winds the yarn 21 around the supply reel shaft 4 onto the supply reel shaft 4. On the other hand, the back tension is applied.

When the first position is in the reproduction state and the take-up reel shaft 3 is rotated by the driving means, the take-up reel rotates in the clockwise direction to pull the magnetic tape 5 to wind it.
The supply reel is pulled by the magnetic tape 5 and rotates clockwise.

Next, the position of the slide lever 27 in FIG.
In this position, the position of the lever 23 does not change, and the lever 29 is in the state of returning from the first position in the counterclockwise direction by stopping the pivot 31.

This is to reduce the back tension.
By moving the slide lever 27 to the left by the driving means, the pin 33 moves upward along the slope of the locking groove 34 and is positioned in the middle flat portion 34c.

At this time, the back tension applied to the magnetic tape 5 is slightly reduced, but it is basically the same as in the first position. Since the biasing force of the spring 19 is stronger than the biasing force of the spring 32, the lever 29 Holds the pin 33 in the middle flat portion 34c while being pulled by the thread 21.

In other words, the slide lever 27 has moved to the left of the first position, the position of the lever 23 has not changed, and the tension on the take-up reel shaft 3 has been relaxed. The yarn 21 wound around is loosened slightly and is moved upward to relax the back tension applied to the supply reel shaft 4.

This second state is the fast-forward state, and the pinch roller 14
Is separated from the capstan 15 and the take-up reel shaft 3 is rotated by the driving means, the magnetic tape 5 is taken up by the take-up reel in a fast-forwarding state.

Next, assuming that the position of the slide lever 27 in FIG. 3 is the third position, at this position, the pin 26 is on the slope of the engaging groove 28, and the pin 33 is the middle flat part of the engaging groove 34. 34c is in a state of being locked respectively.

At this time, the urging force of the spring 19 is
The tension arm 17 rotates in the counterclockwise direction about the pivot 18 and is locked to the fixed post 6 because it is larger than the urging force of 5, 32. Therefore, each lever 2
The yarns 3 and 29 are pulled by the urging force of the springs 25 and 32 to bring the yarns 20 and 21 into a tensioned state, and apply a braking force to each of the take-up reel shaft 3 and the supply reel shaft 4.

That is, the slide lever 27 is moved to the left of the second position, the lever 23 is moved downward to tighten the yarn 20 wound around the take-up reel shaft 3, and the braking force is applied to the take-up reel shaft 3. The lever 2
Although the yarn 9 is almost the same as the fast-forward state, the yarn 21 is in a tensioned state and is wound around the supply reel shaft 4, and the supply reel shaft 4 is in a state where a braking force is applied.

This third position is in a stopped state, and the magnetic tape 5 is stopped without moving.

Further, if the -27 moves further to the left when it slides and reaches the position shown in FIG. 4, the fourth position is assumed. In this position, the lever 23 and the lever 29 are in the first position. It is the opposite.

That is, since the pin 26 reaches the right end of the locking groove 28 and is located in the lower flat portion 28b, the lever 23 is maximally rotated in the counterclockwise direction about the pivot 24 and is stopped. Since the pin 33 reaches the right end of the locking groove 34 and is located in the upper flat portion 34b, the pin 29 is fully rotated counterclockwise about the pivot 31 and is stopped.

At this time, the thread 20 pulls the tension arm 17 toward the take-up reel shaft 3 side against the urging force of the spring 19, and at the same time, the rotational moment of the tension post 7 due to the driving tension of the magnetic tape 5 acts to tension the tension arm 17. And the back tension is applied to the take-up reel shaft 3 by the friction between the yarn 20 and the take-up reel shaft 3.

On the other hand, since the pin 33 reaches the right end of the locking groove 34 and is located in the upper flat portion 34b, the lever 34 is rotated in the counterclockwise direction about the pivot 31 as much as possible and is stopped.
Therefore, the yarn 21 is in a slackened state and does not serve as a load on the supply reel shaft 4.

Therefore, the thread 20 is in a tense state and the thread 21 is in a slack state.

That is, the slide lever 27 is moved further leftward than the third position, and the lever 23 moves the yarn 20 to the take-up reel shaft 3
The lever 29 moves upwards to loosen the yarn 21 wound around the supply reel shaft 4 in the same manner as when the tension of the yarn 20 changes and the back tension is applied to the take-up reel shaft 3 although it moves downward. And the braking force applied to the supply rail shaft 4 is weakened.

The fourth position is in the rewinding state, and if the supply reel shaft 4 is rotated counterclockwise by the driving means, the magnetic tape 5 is formed.
Is wound around the supply reel, and the winding reel shaft 3 is pulled by the magnetic tape 5 and rotated in the counterclockwise direction.

In this manner, in the reproducing state, the take-up reel shaft 3 is not brake-controlled but the supply reel shaft 4 is brake-controlled, so that an appropriate back tension is applied to the magnetic tape 5, and stable tape running can be obtained.

Further, in the fast-forward state, the take-up reel shaft 3 is not brake-controlled, but the supply reel shaft 3 is weakly brake-controlled, so that an appropriate back tension is applied to the magnetic tape 5, and stable tape running is obtained. To be

Further, in the stopped state, the take-up reel shaft 3 and the supply reel shaft 4 are brake-controlled, so that a reliable and stable stopped state can be obtained.

Further, in the rewinding state, the supply reel shaft 4 is not brake-controlled, and the take-up reel shaft 4 is brake-controlled,
Appropriate back tension is applied to the magnetic tape 5, and stable tape running can be obtained.

In other words, in all modes such as playback, fast forward, and rewind,
A stable tension servo mechanism enables tape running. Further, the yarn 20 is wound around the take-up reel shaft 3 and the yarn 21 is wound around the supply reel shaft 4 approximately one revolution, which results from eccentricity of the reel shaft, a change in winding shape, or a change in friction coefficient. Back tension fluctuation can be significantly reduced compared to the one-point pressure bonding type.

Especially in a system where the tape is wound around the rotary head drum while it is rewound, and the signal recorded on the tape is traced by the rotary head drum, it is also possible to use the stable back tension and the degree of freedom of the thread when rewinding. The fact that the tape tension is stabilized is particularly effective.

[Advantage of the Invention] Since the magnetic recording / reproducing apparatus according to the present invention has the above-mentioned configuration, the back tension applied to the magnetic tape varies due to the eccentricity of the reel shaft and the change of the friction coefficient due to the change of the winding diameter. Further, the tape tension can be stabilized even in the case of a system in which the tape is wound around the rotary head drum while the tape is rewound and the signal recorded on the tape is traced by the rotary head drum.

[Brief description of drawings]

1 to 5 show an embodiment of a magnetic recording / reproducing apparatus according to the present invention. FIG. 1 is a plan view of a tape reproducing state, FIG. 2 is a plan view of a tape fast-forwarding state, and FIG. 3 is a plan view of the tape stopped state, FIG. 4 is a plan view of the tape rewinding state, and FIG. 5 is a front sectional view of the magnetic recording / reproducing apparatus. 3 ... Take-up reel shaft 4 ... Supply reel shaft 5 ... Magnetic tape 7 ... Tension post 17 ... Tape running stabilization tension arm 19 ... Spring (arm urging means) 20, 21 ... Thread (No. Leather wire (first and second levers) 25 and 32 ... Spring (first and second biasing means) 27 ... Slide lever (slide member) 28 and 34 ... ... Locking groove (first and second locking portions)

Claims (1)

[Scope of utility model registration request] 1. A magnetic recording / reproducing system in which a magnetic tape is run between a supply reel and a take-up reel via a magnetic head, and information is recorded on the magnetic tape or reproduced from the magnetic tape via the magnetic head. In the device, one end is fixed to the tape stable running tension arm, the other end is fixed to the first lever, and the first linear member mounted on the supply reel, and one end is fixed to the tape stable running tension arm. The second linear member attached to the take-up reel while fixing the end to the second lever, the first locking portion for locking the first lever in a stepwise manner, and the second lever in a stepwise manner The second lever is moved by sliding to one side, and the second linear shape gives back tension to the supply reel shaft, and the first lever moves. Is dynamic,
A fast-forward state in which the first linear shape relaxes the tension applied to the take-up reel shaft and is slid from this playback state to the other to reduce the back tension applied to the supply reel shaft, Rotation of the supply reel and rotation of the take-up reel shaft so as to sequentially switch to a stopped state in which a braking force is applied to the take-up reel shaft and the supply reel shaft, and a rewinding state in which back tension is applied to the take-up reel shaft. A slide member for controlling rotation; a first urging unit for urging the first lever in a direction in which the first filament applies back tension to the take-up reel; and the second filament to the supply reel. Second urging means for urging the second lever in a direction to give back tension, and the first wire and the second wire are the supply reel and the winding reel. Magnetic recording and reproducing apparatus for an arm biasing means for biasing the tape stable traveling tension arm in a direction to prevent rotation of the Le, further comprising a said.