JPH0981983A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the state such as a magnetic head mounted on a drum is not in contact with a magnetic tape and also the magnetic tape does not slackens too much, by suppressing the variance in the tape loosing amount on the drum at the time of loosing in a magnetic recording/reproducing device. SOLUTION: A head output detector 32 is provided for detecting an output voltage of the magnetic head 31, and a reel motor 7 is stopped by control means such as a loosing control circuit 25 and a reel control circuit 24 in response to a loosing command signal (a), and also the speed of a reel motor 6 is reduced, and when a head detecting output signal (i) reaches 0 volt, the reel motor 6 is stopped. Since the timing for stopping the reel motor 6 of take-up side after the reel motor 7 of supply side is stopped is set by the head detecting output signal (i) obtained from the detection of the output voltage from the magnetic head 31 generated by the contact between the magnetic head 31 and the magnetic tape 1, the variance in the tape sagging amount on the drum 2 is suppressed, and the stable loosing is carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing device.

[0002]

2. Description of the Related Art A conventional magnetic recording / reproducing apparatus will be described below with reference to the drawings. FIG. 3 is a block diagram showing a configuration of a conventional magnetic recording / reproducing apparatus. As shown in FIG. 3, the magnetic tape 1 wound around the drum 2 by the posts 17 and 18 is sent out from the supply reel 4, transferred by the capstan motor 5 and the pinch roller 27, and taken up by the take-up reel 3. To be A movable post 15 connected to a spring 16 is provided between the capstan motor 5 and the take-up reel 3 to absorb tape slack at the time of mode transition. Rotational force is applied to the supply reel 4 by the reel motor 7 and rotational force is applied to the take-up reel 3 by the reel motor 6.

The rotation speeds of the reel motors 6 and 7 and the capstan motor 5 are frequency signal generators (hereinafter referred to as "F").
It is detected by 8, 9, 10 and is shaped by the waveform shaping circuits 20, 21, 26, and then applied to the reel control circuit 24 as an FG signal. The reel control circuit 24 detects the winding diameters of the tapes wound on the take-up reel 3 and the supply reel 4 by calculating from these three FG signals, and the drive circuits 19 and 22 so that the torques corresponding to them are generated. The reel motors 6 and 7 are controlled via. The loosening control circuit 25 includes a loosening command signal a for loosening the magnetic tape 1, an FG signal c from the FG 8, and a take-up reel 3.
The winding diameter information b of the tape wound around is input as an input, and the brake solenoid control command signals f and g and the pinch solenoid control command signal h are output.

If the drum 2 is left for a long time with the tension of the magnetic tape 1 applied while the magnetic tape 1 is stopped, the magnetic tape 1 may be scratched or the magnetic head 31 mounted on the drum 2 may be damaged. Since it causes clogging, the magnetic tape 1 is loosened after a lapse of a certain time and the tension is set to 0 g to enter the loosening mode. FIG. 4 is a timing chart showing the operation of the conventional magnetic recording / reproducing apparatus when shifting to the losing mode. A, e, d, c, f, g, and h in FIG. 4 represent the waveforms of the signals indicated by the same reference numerals in FIG.

As shown in FIG. 4, a losing command signal a
Enters the losing mode at a high level and cancels the losing mode at a low level. The control signal e of the reel motor 7 is an analog signal that is proportional to the generated torque, and becomes 0V when entering the losing mode, and the torque of the reel motor 7 becomes 0. At the same time that the torque of the reel motor 7 is set to 0, the brake solenoid control command signal g becomes high level, the brake solenoid 14 is operated via the drive circuit 23, and the reel motor 7 is braked by the brake pad 13 of the reel brake. Call. Further, the pinch solenoid control command signal h also becomes low level at the same timing, and the pinch solenoid 28 is operated via the drive circuit 30 to remove the pinch roller 27 from the capstan motor 5. The control signal d of the reel motor 6 is also an analog signal proportional to the generated torque, and when the loosening mode is entered, the voltage gradually decreases and the torque also decreases. Along with this, the tape tension also gradually decreases, and the spring 16 connected to the movable post 15 gradually contracts, whereby the take-up reel 3 rotates in the delivery direction by the amount by which the tape is pulled. in this way,
By gradually reducing the torque of the reel motor 6, tape slack due to excessive loosening is less likely to occur.

At this time, the FG signal c of the reel motor 6 becomes a pulse train as shown in FIG. 4, and is applied to the losing control circuit 25. Further, winding diameter information b of the take-up reel 3 is also added to the loosening control circuit 25, and the number of pulses of the FG signal c is counted until the value reaches a value preset according to the winding diameter information b. Control signal d of reel motor 6
Voltage continues to drop, and after reaching 0 V at time T, it becomes a negative voltage, and torque is generated in the reel motor 6 in the feed direction. When the value obtained by counting the pulses of the FG signal c reaches a preset value, the brake solenoid control command signal f becomes high level, the brake solenoid 12 is operated via the drive circuit 29, and the reel motor brake pad 11 causes the reel motor to operate. 6
Is braking. At the same time, the control signal d is fixed at 0V. The reel motor 6 requires a torque in the feeding direction because the magnetic tape 1 and the magnetic head 31 are still in contact with each other even when the tension becomes 0 g, which causes head clogging. This is so that the magnetic tape 1 is loosened until there is almost no contact.

[0007]

In such a conventional magnetic recording / reproducing apparatus, the loose amount of the tape fed from the take-up reel 3 at the time of loosening is constant, but the movable post 15, the capstan motor 5, and the post 17 are provided. , 18 and the magnetic tape 1 vary, the amount of tape loosening on the drum 2 varies. Therefore, there is a problem that the magnetic tape 1 and the magnetic head 31 are still in contact with each other, or conversely, the magnetic tape 1 is too slack and the magnetic tape 1 falls off the drum 2.

The present invention solves the above problems and suppresses the variation in the amount of tape looseness on the drum at the time of loosening,
An object of the present invention is to provide a magnetic recording / reproducing apparatus in which a magnetic tape and a magnetic head mounted on a drum do not come into contact with each other and the magnetic tape does not excessively sag.

[0009]

A magnetic recording / reproducing apparatus of the present invention is a first magnetic tape recording / reproducing apparatus for winding or supplying a magnetic tape.
A first reel motor and a second reel motor that apply rotational force to the first reel motor and the second reel motor, respectively.
A drum around which a magnetic tape is wound between a reel and a second reel, a magnetic head mounted on the drum and in contact with the magnetic tape, and a head output detector for inputting and detecting an output voltage from the magnetic head, A first reel brake that brakes the first reel motor, a second reel brake that brakes the second reel motor, a loosening command signal for loosening the magnetic tape wound on the drum, and a head output detector. Of the first and second reel brakes by controlling the operation of the first and second reel brakes.
Controlling means for controlling the torque of the reel motor, and the controlling means controls the torque of the second reel motor to zero in response to the losing command signal.
When the operation of the second reel brake is controlled so as to brake the reel motor and the torque of the first reel motor is controlled to be gradually reduced, when the output signal of the head output detector reaches the set value. The operation of the first reel brake is controlled so as to brake the first reel motor.

According to this structure, in response to the loosening command signal, the second reel motor is stopped and
The first reel motor is decelerated, the output voltage from the magnetic head mounted on the drum is detected by the head output detector, and the first reel motor is stopped when the output signal reaches a set value (for example, zero). Let In this way, the timing of stopping the first reel motor after stopping the second reel motor is set by the signal obtained by detecting the output voltage from the magnetic head generated by the contact between the magnetic head and the magnetic tape. Therefore, there is no variation in the amount of tape looseness on the drum, it is possible to reliably eliminate the contact between the magnetic tape and the magnetic head, and the magnetic tape is not excessively loosened, and stable loosening can be performed.

[0011]

DETAILED DESCRIPTION OF THE INVENTION A magnetic recording / reproducing apparatus according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows a block diagram of a magnetic recording / reproducing apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 32 denotes a head output detector for inputting and detecting an output voltage from the magnetic head 31 generated by the contact between the magnetic head 31 and the magnetic tape 1, and the same components as those in FIG. are doing.

As shown in FIG. 1, the magnetic tape 1 wound around the drum 2 by the posts 17 and 18 has a supply reel 4
Is sent out, is transported by the capstan motor 5 and the pinch roller 27, and is wound on the winding reel 3. A movable post 15 connected to a spring 16 is provided between the capstan motor 5 and the take-up reel 3 to absorb tape slack at the time of mode transition. Rotational force is applied to the supply reel 4 by the reel motor 7 and rotational force is applied to the take-up reel 3 by the reel motor 6.

The rotation speeds of the reel motors 6, 7 and the capstan motor 5 are detected by the FGs 8, 9, 10 respectively, and after waveforms are formed by the waveform shaping circuits 20, 21, 26, F
It is applied to the reel control circuit 24 as a G signal. The reel control circuit 24 detects the winding diameters of the tapes wound on the take-up reel 3 and the supply reel 4 by calculating from these three FG signals, and the drive circuits 19 and 22 so that the torques corresponding to them are generated. The reel motors 6 and 7 are controlled via. The head output voltage obtained by the contact between the magnetic head 31 and the magnetic tape 1 is input to the head output detector 32, and the head detection output signal i is output. The loosening control circuit 25 receives a loosening command signal a for loosening the magnetic tape 1 and a head detection output signal i as inputs, and outputs brake solenoid control command signals f and g and a pinch solenoid control command signal h.

If the magnetic tape 1 is left for a long time while the magnetic tape 1 is stopped and the tension of the magnetic tape 1 is applied to the drum 2, the magnetic tape 1 may be scratched or the magnetic head 31 mounted on the drum 2 may be damaged. Since it causes clogging, the magnetic tape 1 is loosened after a lapse of a certain time and the tension is set to 0 g to enter the loosening mode. FIG. 2 is a timing chart showing the operation of the magnetic recording / reproducing apparatus of the present invention when shifting to the losing mode. FIG.
A, e, d, i, f, g, and h indicate the waveforms of the signals indicated by the same symbols in FIG.

As shown in FIG. 2, a losing command signal a
Enters the losing mode at a high level and cancels the losing mode at a low level. The control signal e of the reel motor 7 is an analog signal that is proportional to the generated torque, and becomes 0V when entering the losing mode, and the torque of the reel motor 7 becomes 0. At the same time that the torque of the reel motor 7 is set to 0, the brake solenoid control command signal g becomes high level, the brake solenoid 14 is operated via the drive circuit 23, and the reel motor 7 is braked by the brake pad 13 of the reel brake. Call. Further, the pinch solenoid control command signal h also becomes low level at the same timing, and the pinch solenoid 28 is operated via the drive circuit 30 to remove the pinch roller 27 from the capstan motor 5. The control signal d of the reel motor 6 is also an analog signal proportional to the generated torque, and when the loosening mode is entered, the voltage gradually decreases and the torque also decreases. Along with this, the tape tension also gradually decreases, and the spring 16 connected to the movable post 15 gradually contracts, whereby the take-up reel 3 rotates in the delivery direction by the amount by which the tape is pulled. in this way,
By gradually reducing the torque of the reel motor 6, tape slack due to excessive loosening is less likely to occur.

At this time, the magnetic head 31 and the magnetic tape 1
Since the contact pressure with the head decreases, the head output voltage decreases,
The head detection output signal i also drops as shown in FIG. The head detection output signal i is applied to the loosening control circuit 25. The voltage of the control signal d of the reel motor 6 continues to decrease until the head detection output signal i becomes 0V, and when the control signal d becomes 0V at time T, it becomes a negative voltage thereafter.
Torque in the feed direction is generated in the reel motor 6. When the head detection output signal i becomes 0V, that is, when the contact between the magnetic head 31 and the magnetic tape 1 is lost, the brake solenoid control command signal f becomes high level, and the brake solenoid 12 is operated via the drive circuit 29. The reel motor 6 is braked by the brake pad 11 of the reel brake.

At the same time, the control signal d is fixed at 0V. Even if the tension becomes 0 g, the magnetic tape 1 and the magnetic head 31 are still in contact with each other because the torque of the reel motor 6 in the feeding direction is required. This is so that the magnetic tape 1 is loosened until there is almost no contact.

The take-up reel 3 corresponds to the first reel, the supply reel 4 corresponds to the second reel, the reel motor 6 corresponds to the first reel motor, and the reel motor 7 corresponds to the second reel motor. Corresponding to the reel motor, the brake pad 11, the brake solenoid 12 and the drive circuit 29 correspond to the first reel brake, the brake pad 13, the brake solenoid 14 and the drive circuit 23 correspond to the second reel brake, The losing control circuit 25 and the reel control circuit 24 correspond to control means for controlling the operations of the first and second reel brakes and the torques of the reel motors 6 and 7 by the losing command signal a.

As described above, according to the embodiment of the present invention, the head output detector 32 which receives and detects the output voltage from the magnetic head 31 is provided, and the control of the losing control circuit 25 and the reel control circuit 24 is performed. In response to the loosening command signal a, the means stops the reel motor 7 to fix the supply reel 4, decelerates the reel motor 6, and detects the output voltage from the magnetic head 31 attached to the drum 2 by head output detection. When the head detection output signal i reaches 0V (set value), the reel motor 6 is stopped and the take-up reel 3 is fixed. In this way, the output voltage from the magnetic head 31 generated by the contact between the magnetic head 31 and the magnetic tape 1 is detected at the timing of stopping the reel motor 6 on the winding side after stopping the reel motor 7 on the supply side. Head detection output signal i
Therefore, even if the frictional force between the movable post 15, the capstan motor 5, the posts 17 and 18 and the magnetic tape 1 varies, the amount of tape slack on the drum 2 does not vary, and the Tape 1 and magnetic head 31
It is possible to carry out stable loosening without contact with the magnetic tape 1 and without loosening the magnetic tape 1 too much.

In the embodiment of the present invention, the supply reel 4 is fixed and the take-up reel 3 is used in the loosening mode.
Although the magnetic tape 1 is pulled out from the magnetic tape 1, the take-up reel 3 may be fixed and the magnetic tape 1 may be pulled out from the supply reel 4. In the embodiment of the invention described above,
The set value of the head detection output signal i for stopping the reel motor 6 is set to 0V, but the set value of the head detection output signal i corresponds to zero of the output voltage from the magnetic head 31, and is not necessarily 0V. There is no need to do it, and a certain fixed value will do.

[0021]

As described above, the magnetic recording / reproducing apparatus of the present invention is provided with the head output detector for inputting and detecting the output voltage from the magnetic head, and the control means responds to the loosening command signal, Controlling the torque of the second reel motor to zero, controlling the operation of the second reel brake so as to brake the second reel motor, and controlling the torque of the first reel motor to gradually decrease; The operation of the first reel brake is controlled so as to brake the first reel motor when the output signal of the head output detector reaches the set value. That is, in response to the losing command signal, the second reel motor is stopped, the first reel motor is decelerated, and the output voltage from the magnetic head attached to the drum is detected by the head output detector.
When the output signal reaches a set value (for example, zero), the first
Stop the reel motor of. In this way, the timing of stopping the first reel motor after stopping the second reel motor is set by the signal obtained by detecting the output voltage from the magnetic head generated by the contact between the magnetic head and the magnetic tape. Therefore, there is no variation in the amount of tape looseness on the drum, it is possible to reliably eliminate the contact between the magnetic tape and the magnetic head, and the magnetic tape is not excessively loosened, and stable loosening can be performed.

[Brief description of drawings]

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

FIG. 2 is a timing chart showing the operation of the magnetic recording / reproducing apparatus according to the embodiment of the present invention.

FIG. 3 is a block diagram showing the configuration of a conventional magnetic recording / reproducing device.

FIG. 4 is a timing chart showing the operation of a conventional magnetic recording / reproducing apparatus.

[Explanation of symbols]

 1 magnetic tape 2 drum 3 take-up reel (first reel) 4 supply reel (second reel) 5 capstan motor 6,7 reel motor 8, 9, 10 frequency signal generator 11 brake pad 12 brake solenoid 13 brake Pad 14 Brake solenoid 15 Movable post 16 Spring 17, 18 Post 19 Drive circuit 20,21 Waveform shaping circuit 22,23 Drive circuit 24 Reel control circuit (control means) 25 Loss control circuit (control means) 26 Waveform shaping circuit 27 Pinch roller 28 pinchsonoid 29,30 drive circuit 31 magnetic head 32 head output detector

Claims (1)

[Claims] 1. A first reel motor and a second reel motor for applying a rotational force to a first reel and a second reel for winding or supplying a magnetic tape, respectively, and the first reel and the first reel motor. A drum around which the magnetic tape is wound between two reels, a magnetic head attached to the drum and in contact with the magnetic tape, and a head output detector for inputting and detecting an output voltage from the magnetic head, A first reel brake for braking the first reel motor, a second reel brake for braking the second reel motor, a loosening command signal for loosening the magnetic tape wound on the drum, and The output signal of the head output detector is input to control the operations of the first and second reel brakes, and
And control means for controlling the torque of the second reel motor, wherein the control means is responsive to the losing command signal,
To control the torque of the second reel motor to zero, control the operation of the second reel brake so as to brake the second reel motor, and gradually reduce the torque of the first reel motor. Control so that when the output signal of the head output detector reaches a set value, the first
The magnetic recording / reproducing apparatus configured to control the operation of the first reel brake so as to brake the reel motor.