JPH05198058A - Magnetic recording and reproduction device - Google Patents

Abstract

PURPOSE:To reduce variation in tape tension even if a tape speed varies by switching the torque of a reel motor in loading or unloading mode according to the position of a mechanism system. CONSTITUTION:A loading control signal (c) is a signal for controlling the torque of the reel motor 1 in the loading mode and an unloading control signal (d) is the signal in the unloading mode. Those signals are connected to a switch 3 and switched with t 1st motor command (a) and a 2nd monitor command (b) to control the reel motor 1 through a driver 2. A frequency power generator 7 generates a frequency which is proportional to the rotational frequency of a loading motor 5 and applies it to a waveform circuit 8. The waveform generation output (f) is applied to a frequency controller 9, which controls the rotating speed of the loading motor 5 to a constant speed through a driver 6. The waveform generation output (f) is applied to a torque switching circuit 4 as well to reduce the variation in tape tension.

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 apparatus having a function of pulling out a magnetic tape from a cassette and loading it on a rotary drum.

[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 the structure of a conventional magnetic recording / reproducing apparatus. In the figure, the loading control signal c
Is set to a constant voltage by the voltage dividing resistors 10 and 11. Similarly, the unloading control signal d is
It is set to a constant voltage in 3. The reel control signal e is a signal for controlling the torque of the reel motor 1 in a mode other than the loading or unloading mode. The loading control signal c, the unloading control signal d, and the reel control signal e are connected to the switch 3 and switched by the first mode command a and the second mode command b. The loading control signal c is turned on in the loading mode, the unloading control signal d is turned on in the unloading mode, and the reel control signal e is turned on in other modes. The output signal of the switch 3 controls the torque of the reel motor 1 via the driver 2. The loading control signal h determines the torque of the loading motor 5, is set to a constant voltage by the voltage dividing resistors 14 and 15, and is applied to the driver 6. The first mode command a and the second mode command b are also added to the driver 6 to control the rotation direction and on / off of the loading motor 5.

[0004]

In such a conventional magnetic recording / reproducing apparatus, in the loading or unloading mode, when the magnetic tape is pulled out from the cassette by the mechanism system for continuously applying a constant torque to the reel motor, or in the cassette. There is a problem that the tape tension changes greatly due to the fluctuation of the tape speed when the magnetic tape is stored in the tape, which causes damage to the tape.

The present invention solves the above problems, and an object of the present invention is to provide a magnetic recording / reproducing apparatus capable of reducing the fluctuation of the tape tension in the loading or unloading mode.

[0006]

In order to achieve the above object, according to the present invention, a frequency generating means for generating a frequency proportional to the rotation speed of a loading motor and a loading position for detecting a loading position from an output signal of the frequency generating means. Torque switching means for switching the torque of the reel motor according to the output signals of the detection means and the loading position detection means is provided.

[0007]

With the above structure, in the loading or unloading mode, the torque of the reel motor is changed according to the position of the mechanism system so that the fluctuation of the tape tension is reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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. The loading control signal c is in the loading mode, and the unloading control signal d is in the unloading mode, the reel control signal e.
Is a signal for controlling the torque of the reel motor 1 in the other modes. They are connected to switch 3,
The reel motor 1 is controlled via the driver 2 by switching between the first mode command a and the second mode command b. The frequency generator 7 generates a frequency proportional to the rotation speed of the loading motor 5 and applies it to the waveform shaping circuit 8. The waveform shaping output f is applied to the speed control circuit 9 and is controlled via the driver 6 so that the rotation speed of the loading motor 5 becomes constant. The waveform shaping output f is also applied to the torque switching circuit 4.

FIG. 2 is a timing chart showing the operation of the magnetic recording / reproducing apparatus of the present invention. The first mode command a becomes H level only when the loading motor 5 is turned on A
Signal. The second mode command b determines the rotation direction of the loading motor 5, and is a signal shown in B of FIG. 2 which becomes L level in the loading direction and H level in the unloading direction. The waveform shaping output f is a pulse signal such as C proportional to the rotation speed of the loading motor 5. The torque switching circuit 4 detects the position of the mechanical system by the number of pulses of the waveform shaping output f after the loading is started, and the loading control signal c as shown in D of FIG. 2 is set so that the fluctuation of the tape tension at the time of loading is reduced. Is output. Similarly, after the start of unloading, an unloading control signal such as E in FIG. 2 is set so that the fluctuation of the tape tension during unloading becomes small.

As described above, according to the magnetic recording / reproducing apparatus of the present invention, the fluctuation of the tape tension can be reduced by switching the torque of the reel motor according to the position of the mechanical system in the loading or unloading mode.

[0012]

As is apparent from the above embodiments, according to the present invention, the tape speed when the magnetic tape is pulled out from the cassette by the mechanism system or when the magnetic tape is stored in the cassette in the loading or unloading mode is set. Even if there is a change, the torque of the reel motor is switched according to the position of the mechanical system, so that it is possible to provide a magnetic recording / reproducing apparatus with a small change in tape tension.

[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 apparatus.

[Explanation of symbols]

 4 Torque switching circuit 7 Frequency generator 9 Speed control circuit

Claims (2)

[Claims] 1. A magnetic recording device comprising frequency generating means for generating a frequency proportional to the rotation speed of a loading motor, and torque switching means for detecting the loading position from the output signal of the frequency generating means and switching the torque of the reel motor. Playback device. 2. The magnetic recording / reproducing apparatus according to claim 1, further comprising speed control means for controlling the output signal of the frequency generation means so as to have a constant frequency.