JP2001076399A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make eliminable a slackening of tape and the damage of the tape without being affected by the variation in tape transferring loads at the time of the deceleration for the fast-feeding/the rewinding of the tape. SOLUTION: This device has a constitution capable of changing the reel braking power by the position of a cam lever 5 between a nonload mode in which the reel braking power is not added and a stop mode in which the reel braking power is added. In this case, at the time of the deceleration for the fast-feeding/the rewinding of the tape, the reel braking power is controlled by moving the cam lever 5 in accordance with a tape speed and a tape transferring load which are obtained from detection values of a revolving speed of reel detecting part 11 and a load current of capstan motor detecting part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording and reproducing apparatus for recording and reproducing video signals and audio signals on a magnetic tape.

2. Description of the Related Art In recent years, in a magnetic recording / reproducing apparatus, the time required for fast-forwarding / rewinding a tape has been reduced. In order to shorten the fast-forward / rewind time, it is necessary to increase the tape speed by sudden acceleration, and then to suddenly decelerate and stop.
If the tape is rapidly decelerated during high-speed transfer of the tape, the amount of tape supplied from the supply side reel will be larger than the amount of tape wound up by the take-up side reel, causing tape slack and causing problems such as tape wrapping. I do. A conventional magnetic recording / reproducing apparatus will be described below with reference to the drawings. FIG. 3 is a flowchart showing a first example of a fast deceleration operation of fast forward / rewind of a conventional magnetic recording / reproducing apparatus. In a conventional magnetic recording / reproducing apparatus, at the time of deceleration of fast-forward / rewind, a reel braking force is applied by a method as shown in FIG. 3 so that a winding tape amount and a supply tape amount become the same. The rotation of the reel on the take-up side and the supply side is braked to eliminate slack in the tape. FIG. 3 (a)
5 is a graph showing the tape speed at the time of deceleration in fast-forward / rewind, with the vertical axis representing the tape speed and the horizontal axis representing the steps of the mode movement operation of the mechanism. FIG. 3B shows the magnitude of the reel braking force in each operation mode of the mechanism and the locus of the mode movement of the mechanism at the time of deceleration in fast-forward / rewind. Hereinafter, the operation will be described. First, in step A, high-speed transport of the tape is performed at the tape speed Vm in the no-load mode in which the reel braking force is hardly applied.
When the deceleration start point is reached, in step B, the mode moves to a stop mode in which a constant reel braking force Pm is applied, the speed is reduced, and after reaching a predetermined tape speed Ve, step C is performed.
Then, the mode is again moved to the no-load mode to transfer the tape, and after detecting the start and end of the tape, in step D, the mode is again moved to the stop mode and stopped. FIG. 4 shows a second example of a conventional magnetic recording / reproducing apparatus. FIG. 4 is a flowchart of a second example of the fast-rewind / rewind operation of the conventional magnetic recording / reproducing apparatus. There is a magnetic recording / reproducing apparatus having a low load mode in which a constant reel braking force Ps set lower than the stop mode is applied between the no-load mode and the stop mode. Hereinafter, the operation will be described. Tape speed Vm
When the deceleration start point is reached during high-speed transfer of the tape at step B, in step B, the mode is moved to the low load mode, the reel braking force Ps is added to decelerate, and after reaching the predetermined tape speed Ve, at step C, Then, the mode is moved to the no-load mode again to transfer the tape, and after detecting the start and end of the tape, in step D, the mode is moved to the stop mode and the reel braking force P
Add m and stop.

However, in the above-mentioned conventional configuration, when the fast-forward / rewind operation is decelerated, the mode is moved to a predetermined predetermined operation mode of the mechanism to apply a predetermined predetermined reel braking force. Therefore, there has been a problem that the reel braking force applied due to the variation in the tape transfer load becomes excessively large, causing tape damage, or the reel braking force becomes excessively small, resulting in slack of the tape. SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic recording / reproducing apparatus which eliminates tape slack and tape damage without being affected by variations in tape transfer load during deceleration of fast-forward / rewind. I do.

In order to achieve this object, a magnetic recording / reproducing apparatus according to the present invention comprises a pair of reels for supplying / rewinding a tape, a driving means for performing fast-forward / rewind, and a fast-forward / rewind. Tape speed detecting means for detecting the tape speed during rewinding, tape load detecting means for detecting the tape transfer load during fast forward / rewinding, no load mode in which no braking force is applied to the reel, and braking force applied to the reel A reel braking means for changing a reel braking force between a stop mode and a stop mode, wherein the tape output from the tape speed detecting means and the tape load detecting means at the time of deceleration of fast-forward / rewind. The reel braking force is controlled by moving the mechanism mode between the no-load mode and the stop mode according to the speed and the tape transfer load. With this configuration, it is possible to eliminate the slack of the tape and the tape damage without being affected by the variation in the tape transfer load during the deceleration of the fast-forward / rewind.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 of the present invention comprises a pair of reels for feeding / rewinding a tape, a driving means for fast-forwarding / rewinding, and a tape speed during fast-forwarding / rewinding. Between a no-load mode in which a braking force is not applied to a reel and a stop mode in which a braking force is applied to a reel; a tape load detecting means for detecting a tape transfer load during fast-forward / rewind; A magnetic recording / reproducing apparatus provided with a reel braking means for changing a reel braking force by using a tape speed detecting means and a tape load detecting means which output a tape speed and a tape transfer load when decelerating fast-forward / rewind. Accordingly, the reel braking force is controlled by moving the mode of the mechanism between the no-load mode and the stop mode. By changing the mode of the mechanism between the no-load mode and the stop mode according to the tape speed and the tape transfer load during deceleration, and changing the reel braking force, the tape is not affected by variations in the tape transfer load. It has the effect that slack and tape damage can be eliminated. Hereinafter, an embodiment of the present invention will be described with reference to FIGS. (Embodiment 1) FIG. 1 is a block diagram showing a configuration of a magnetic recording and reproducing apparatus according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 1 denotes a capstan motor, and 2 denotes a drive transmission unit that transmits rotation of the capstan motor to a reel.
For example, it is constituted by a belt and a gear. Reference numeral 3 denotes a pair of reels on the supply side and the take-up side of the tape cassette, and 4 denotes a reel braking unit for applying a braking force to the reels 3 on the supply side and the take-up side.
For example, it is composed of a band, a coil spring that applies a tightening force to the band, and a lever that changes the load of the coil spring. Reference numeral 5 denotes a cam lever that controls the movement of the reel braking unit 4 by a cam according to the operation mode of the mechanism and changes the reel braking force. 6 is a mechanism driving motor for moving the cam lever 5 to move the operation mode of the mechanism, 7 is a mode detection switch for detecting the mode of the mechanism based on the position of the cam lever 5, 8 is a mechanism control unit for controlling the whole mechanism, and 9 is a cap control. Capstan motor control unit that controls the stun motor, 10 is fast forward /
This is a capstan motor load current detection unit as a tape load detection unit that detects a tape transfer load during rewinding. Since the load current of the capstan motor increases and decreases according to the increase and decrease of the tape transfer load, the detection of the tape transfer load can be substituted by detecting the capstan motor load current. Numeral 11 denotes a reel rotation number detecting unit for detecting the number of reel rotations on the supply side and the winding side as tape speed detection means for detecting the tape speed during fast forward / rewind. The tape speed is calculated from the rotation speed of the supply reel and the rotation speed of the take-up reel. As the operation mode of the mechanism, a no-load mode in which a braking force is not applied to the reel by a cam for controlling the reel braking unit 4 provided in the cam lever 5 and a stop mode in which a braking force is applied to the reel are adjacent to each other. Is set. Further, as the cam lever 5 moves from the no-load mode to the stop mode,
The cam of the cam lever 5 is set so that the reel braking force increases at a constant rate. The fast forward / rewind operation of the magnetic recording / reproducing apparatus configured as described above will be described below with reference to FIG. First, when a fast forward / rewind command is transmitted to the mechanism control unit 8,
When the mechanism drive motor 6 is driven, the cam lever 5 moves, the mode is moved, and when the no-load mode is detected by the mode detection switch 7, the mechanism drive motor 6 stops. Thereafter, a command is transmitted from the mechanism control unit 8 to the capstan motor control unit 9, the capstan motor 1 is driven, the rotation is transmitted to the drive-side reel 3 via the drive transmission unit 2, and the tape is fast-forwarded / rewound. A return is made. During the fast-forward / rewind of the tape, the reel speed detector 11 detects the tape speed and the remaining tape until the end of the cassette tape at the time of fast-forward from the rotation speed of the supply-side reel and the rotation speed of the take-up reel. At the time of rewinding and rewinding, the remaining amount of the tape up to the beginning of the cassette tape is calculated. The calculated tape speed and remaining tape amount and the capstan motor load current detected by the capstan motor load current detection unit 10 are fed back to the mechanism control unit 8 as needed. When the tape is fast-forwarded / rewinded and the remaining amount of the tape reaches a predetermined amount, deceleration is started. This will be described below with reference to FIG. FIG. 2 is a flow chart of a fast-forward / rewind deceleration operation of the magnetic recording / reproducing apparatus according to the first embodiment of the present invention. Is shown. First, in step A, when the tape reaches the deceleration start point during high-speed tape transfer in the no-load mode, in step B, a deceleration command is transmitted from the mechanism control unit 8 to the capstan motor control unit 9, and the capstan motor is controlled. Decrease one revolution. At the same time, the mechanism driving motor 6 is driven, the cam lever 5 is moved from the no-load mode to the stop mode, and the reel braking force is applied by the reel braking unit 4 to reduce the rotation speed of the reel.
Decrease tape speed. As described above, the reel braking force is configured to increase steadily as the cam lever 5 moves from the no-load mode to the stop mode, as shown in FIG. 2B. While the cam lever 5 is moving from the no-load mode to the stop mode, the detected tape speed is reduced to a predetermined value Ve, or the detected capstan motor load current exceeds a predetermined value. Up to this point, the cam lever 5 continues to move in the direction of the stop mode to increase the reel braking force. The cam lever 5 moves up to the stop mode position at the maximum. When the tape speed has been reduced to the predetermined tape speed Ve, in step E, the mechanism drive motor 6 is driven, and the cam lever 5 is moved again.
After moving to the no-load mode, the capstan motor control unit 9 simultaneously controls the capstan motor 1 to transfer the tape at a predetermined tape speed Ve. After detecting the end of the tape in fast-forward and the start of the tape in rewind, Step F
Then, the mechanism drive motor 6 is driven, the cam lever 5 is moved to the stop mode, the reel braking force Pm is applied, and at the same time, the rotation of the capstan motor 1 is stopped by the capstan motor control unit 9 to stop the tape transfer. I do. Also, if the capstan motor load current exceeds a predetermined value before decelerating to a predetermined tape speed Ve,
If a greater reel braking force is applied, an excessive load may be applied to the tape and tape damage may occur. In step C, the cam lever 5 is temporarily moved to the no-load mode to reduce the reel braking force. After the tape transfer load is reduced, the cam lever 5 is moved again in the stop mode in step D to increase the reel braking force. Thereafter, steps C and D are repeated while detecting the tape speed and the capstan motor load current until the tape speed is reduced to the predetermined tape speed Ve. After decelerating to the predetermined tape speed Ve, the operation is performed in the order of the steps E and F to stop the tape transfer.
As described above, according to the first embodiment, the reel braking force is increased at a constant rate by moving the cam lever 5 in the direction from the no-load mode in which the reel braking force is not applied to the stop mode in which the reel braking force is applied. A reel rotation number detector 11 for detecting the reel rotation number on the supply side and the winding side for detecting a tape speed, and a capstan for detecting a capstan motor load current for detecting a load during tape transfer. A motor load current detection unit 10 is provided to
In response to variations in the tape transfer load, the mode of the mechanism is moved by the cam lever 5 between the no-load mode and the stop mode according to the tape speed and the tape transfer load during the rewinding to change the reel braking force. Reel braking force can be added, and tape slack and tape damage can be eliminated without being affected by variations in the tape transfer load.

As described above, according to the present invention, the mode of the mechanism is moved from the no-load mode to the stop mode in accordance with the tape speed and the tape transfer load when the tape is fast-forwarded / rewinded and the reel braking force is reduced. By changing
An excellent effect is obtained in that slack of the tape and tape damage can be eliminated without being affected by variations in the tape transfer load.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a magnetic recording and reproducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a flowchart of a fast-forward / rewind deceleration operation of the magnetic recording and reproducing apparatus according to the first embodiment.

FIG. 3 is a flowchart of a first example of a fast-rewind / rewind deceleration operation of a conventional magnetic recording / reproducing apparatus.

FIG. 4 is a flowchart of a second example of a fast deceleration / rewind operation of the conventional magnetic recording / reproducing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Capstan motor 2 Drive transmission part 3 Reel (supply side / rewind side) 4 Reel braking part (supply side / rewind side) 5 Cam lever 6 Mechanism drive motor 7 Mode detection switch 8 Mechanism control part 9 Capstan motor control part 10 Capstan motor load current detector 11 Reel rotation speed detector

Claims (1)

[Claims] 1. A pair of reels for supplying / rewinding a magnetic tape, driving means for performing fast-forward / rewind, and
Tape speed detecting means for detecting a tape speed during rewinding, tape load detecting means for detecting a tape transfer load during fast forward / rewinding, a no-load mode in which no braking force is applied to the reel, and a braking force for the reel And a reel braking means for changing a reel braking force between a stop mode and a stop mode to which the tape speed detection means and the tape load detection means are decelerated during fast-forward / rewind. A magnetic recording / reproducing apparatus, wherein a reel braking force is controlled by moving a mechanism mode between the no-load mode and the stop mode according to a tape speed and a tape transfer load output.