JPH0935370A - Magnetic tape traveling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provided a device at low cost without having secular changes. SOLUTION: A semifixed resistor 14 of a jig for speed adjustment 15 is adjusted so as to make an output signal regenerated from a tape of a reference frequency become the reference frequency, and an adjusted value by dividing a voltage Vcc is digitized by an A-D converter 13, and this value is written as an FG signal target period in a nonvolatile memory 16. A period of an FG signal generated from an FG signal generator 11 by the rotation of a capstan motor 10 is measured and digitized by a period measuring instrument 12 and is inputted to a comparator 20, where it is compared with the value of the nonvolatile memory 16, and is inputted to a motor control circuit 21 to control a motor driver 22 so that the capstan motor 10 is rotated at a target revolving speed.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art In recent years, in a magnetic tape running apparatus in a magnetic recording / playback apparatus for recording and playing back audio / video and data, etc., a rotation of a motor for running a magnetic tape generates a signal proportional to the number of rotations. A method of digitally controlling by a microcomputer or the like using an output signal of a frequency generator (hereinafter abbreviated as FG) or the like is often used.

The above-described conventional magnetic tape running device will be described below with reference to the drawings. FIG. 3 is a block diagram of a conventional magnetic tape running device.
In FIG. 3, a magnetic tape 5 stretched between reels 3 and 4 has its magnetic surface in contact with a reproducing head 6 and is sandwiched between a capstan shaft 1 and a pinch roller 2. As the reproducing means, the output of the reproducing head 6 is input to the reproducing amplifier 7, the output of the reproducing amplifier 7 is input to the power amplifier 8, and the output of the power amplifier 8 is connected to the speaker 9.

On the other hand, the rotating shaft of the capstan motor 10 is directly connected to the capstan shaft 1 and the FG signal generator 11. The output of the FG signal generator 11 is input to the period measuring device 12, and the output of the period measuring device 12 is added to one comparison input of the comparator 20. To the other comparison input of the comparator 20, the output of the AD converter 13a connected to the semi-fixed resistor 14a for dividing the voltage Vcc is applied. Comparator 20
Is connected to control the capstan motor 10 via a motor control circuit 21 and a motor driver 22. The motor control circuit 21 and the motor driver 22 constitute a motor control means.

The above construction is described below. The magnetic tape 5 is sent in the direction of arrow A by the rotating capstan shaft 1 and the pinch roller 2, and the running speed of the magnetic tape 5 changes depending on the rotation speed of the capstan motor 10. The rotation speed of the capstan motor 10 is adjusted by the resistance value of the semi-fixed resistor 14a. That is, the voltage Vcc applied to the semi-fixed resistor 14a is divided into a voltage value corresponding to the adjustment position, and the AD converter 13a.
Is quantified by. The value is input to the comparator 20 as the target value of the FG signal cycle. On the other hand, capstan motor 1
When 0 rotates, the FG signal is generated by the FG signal generator 11, and the cycle is measured by the cycle measuring device 12 and input to the comparator 20 as a numerical value. By comparing the FG signal target period input from the AD converter 13a and the FG signal period input from the period measuring device 12 with the comparator 20, and inputting the result to the motor control circuit 21 to control the motor driver 22. It is possible to control the rotation speed of the capstan motor 10 in the direction in which the FG signal target cycle and the FG signal cycle input from the cycle measuring device 12 coincide with each other and rotate the capstan motor 10 at a predetermined target rotation speed.

[0006]

However, the above-described conventional magnetic tape running device has a problem that since it uses a semi-fixed resistor, it changes over time and an AD converter is also required. .

The present invention has been made to solve the above-mentioned problems of the prior art, and has as its object the provision of a magnetic tape running device which is stable over time, stable, and inexpensive.

[0008]

To achieve the above object, a magnetic tape running apparatus of the present invention comprises a reproducing means for reading a signal recorded on a magnetic tape, and a motor for running the magnetic tape at a predetermined speed. FG signal generating means for generating an FG signal corresponding to the running speed of the magnetic tape, cycle measuring means for measuring the cycle of the FG signal of the FG signal generating means and outputting data, and FG signal target cycle of the motor A non-volatile memory for storing data, a comparing means for comparing the output data of the cycle measuring means with the FG signal target cycle data stored in the non-volatile memory and outputting the comparison result, According to the comparison result, the motor control means for controlling the rotation speed of the motor is provided in the direction in which the comparison inputs match.

[0009]

According to the present invention, the output signal of the FG signal generating means for generating the FG signal corresponding to the running speed of the magnetic tape with reference to the FG signal target cycle stored in the non-volatile memory in the comparing means is constituted by the above-mentioned structure. The rotation speed of the motor is controlled via the motor control means so that the cycles match so that the running speed of the magnetic tape reaches a predetermined target value.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic tape running device of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a magnetic tape running device according to a first embodiment of the present invention. In FIG. 1, components having the same functions as those of the conventional example shown in FIG. 3 are designated by the same reference numerals, and detailed description thereof will be omitted. 3 is different from FIG. 3 in that instead of providing an AD converter in which the semi-fixed resistor for dividing the voltage Vcc in the conventional example of FIG. 3 is connected to the other input of the comparator 20, a nonvolatile memory 16 is connected and at the time of adjustment. The point is that the speed adjusting jig 15 having the AD converter 13 to which the semi-fixed resistor 14 for dividing the voltage Vcc is connected is connected.

The operation of the magnetic tape running device of the first embodiment constructed as above will be described below.
First, the magnetic tape 5 is sent out in the direction of arrow A by the capstan shaft 1 and the pinch roller 2 which are rotated by the capstan motor 10, and the speed of the magnetic tape 5 changes depending on the rotation speed of the capstan motor 10. At the time of adjustment, a magnetic tape on which a reference frequency, for example, 1 kHz is recorded is reproduced, and the reproduction frequency is measured by a frequency measuring device or a period measuring device (not shown).

The rotation speed of the capstan motor 10 can be adjusted by a speed adjusting jig 15 composed of a semi-fixed resistor 14 and an AD converter 13. The voltage value adjusted by dividing the voltage Vcc by the semi-fixed resistor 14 is adjusted by adjusting the semi-fixed resistor 14 so that the output signal reproduced from the magnetic tape having the reference frequency recorded becomes the reference frequency. It is digitized by 13, and the value is written in the nonvolatile memory 16 as a target value of the FG signal cycle, and the stored numerical value of the nonvolatile memory 16 is input to the comparator 20.

On the other hand, when the capstan motor 10 rotates, the FG signal generator 11, which is an FG signal generating means, causes the FG signal to be generated.
A signal is generated, and the period is measured by the period measuring device 12 which is the period measuring means, the period is digitized, and is inputted to the comparator 20 which is the comparing means. The comparator 20 compares the FG signal target cycle with the FG signal cycle, and inputs the result to the motor control circuit 21 to control the motor driver 22 and control the capstan motor 10 to rotate at the target rotation speed. To do. When the adjustment is finished here, the final stored numerical value of the nonvolatile memory 16 becomes the FG signal cycle target.

When actually adjusting the speed, the reference frequency,
For example, the semi-fixed resistor 14 is adjusted so that the reproduction signal becomes 1 kHz by reproducing the magnetic tape recorded with 1 kHz and reading the output from the reproduction amplifier 7 by the frequency counter, and stores it in the non-volatile memory 16. After adjustment, even if the speed adjustment jig 15 is removed, the nonvolatile memory 16
The speed of the capstan motor is controlled by the target period of the FG signal recorded in. As described above, according to the present embodiment, since the semi-fixed resistor is not used after the adjustment is completed, it is possible to configure an inexpensive magnetic tape running device that does not change with time.

Although the rotating shaft of the capstan motor 10 has been described as being directly connected to the capstan shaft 1 and the FG signal generator 11, an idler or a belt is provided between the capstan motor 10 and the capstan shaft 1. The power may be transmitted via, for example, the same between the capstan motor 10 and the FG signal generator 11.

Next, a magnetic tape running device according to a second embodiment of the present invention will be described in detail with reference to FIG.
FIG. 2 is a block diagram showing the configuration of a magnetic tape running device according to the second embodiment of the present invention. 2, the same components as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted. The difference from FIG. 1 is that the output of the regenerative amplifier is connected to a second cycle measuring device 17 that reads the cycle of the reproduced signal, and the FG signal target cycle is calculated based on the read cycle that is the output of the cycle measuring device 17. The calculation means 18 is connected to the calculation means 18.
Is added to the non-volatile memory 16 via the switch 19 which is turned on during speed adjustment.

The above-mentioned construction is described below. When the speed is adjusted, the switch 19 is turned on to reproduce the magnetic tape on which the reference frequency, for example, 1 kHz is recorded. The initial rotation speed of the capstan motor 10 rotates at the FG signal target cycle (initial value) given by the calculating means 18. The output from the reproduction amplifier 7 is read by the cycle measuring device 17, and assuming that the reproduction signal cycle of this magnetic tape is 2 msec when the FG signal target cycle (initial value) is 4 msec, the arithmetic means 18 In the case of the reproduction signal, the reference frequency is 1 kHz (cycle =
1 msec) to set the FG signal target period to 2 ms
The result is output to the non-volatile memory 16 and stored therein. After completing the speed adjustment, turn off the switch 19,
After the adjustment, the speed of the capstan motor is controlled based on the FG signal target period 2 msec stored in the non-volatile memory 16.

In the second embodiment, the output of the regenerative amplifier 7 is input to the period measuring device 17, but the reproduction signal is not limited to this position and the signal level at which the period measuring device 17 can operate is not limited. It can be anywhere as long as you can get it. Further, with the configuration of this embodiment, the speed can be readjusted at any time if there is a magnetic tape recording the reference frequency. However, if readjustment is not necessary, the period measuring instrument 17 and the calculating means 18 are non-volatile. Since it is unnecessary after it is stored in the property memory 16, it may be separated as a speed adjusting jig.

The numerical values given above are merely examples, and the present invention is not limited to these values.

[0020]

As described above, according to the present invention, the reproducing means for reading the signal recorded on the magnetic tape, the motor for running the magnetic tape at a predetermined speed, and the running speed of the magnetic tape are supported. F to generate the generated FG signal
G signal generating means, cycle measuring means for measuring the cycle of the FG signal of the FG signal generating means and outputting the data, non-volatile memory for storing the FG signal target cycle data of the motor, and the cycle measuring means. Of the motor output signal and the FG signal target cycle data stored in the non-volatile memory and outputs the comparison result, and the rotation speed of the motor in the direction in which the comparison input matches the comparison result of the comparison unit. By controlling the motor so that the FG signal cycle of the motor for driving the capstan becomes the FG signal target cycle stored in the non-volatile memory. It is possible to provide a simple magnetic tape running device.

[Brief description of drawings]

FIG. 1 is a block diagram of a magnetic tape running device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a magnetic tape running device according to the second embodiment of the same.

FIG. 3 is a block diagram of a conventional magnetic tape running device.

[Explanation of symbols]

 1 Capstan Axis 2 Pinch Roller 5 Magnetic Tape 6 Reproducing Head 7 Reproducing Amplifier 8 Power Amplifier 10 Capstan Motor 11 FG Signal Generator 12 Cycle Measuring Instrument 13 AD Converter 14 Half Fixed Resistor 15 Speed Adjustment Jig 16 Nonvolatile Memory 17 Second period measuring device 18 Computing means 19 Switch 20 Comparator 21 Motor control circuit 22 Motor driver

Claims (2)

[Claims] 1. A reproducing means for reading a signal recorded on a magnetic tape, a motor for running the magnetic tape at a predetermined speed, and an FG signal generating means for generating an FG signal corresponding to the running speed of the magnetic tape. A cycle measuring means for measuring the cycle of the FG signal of the FG signal generating means and outputting the data; a non-volatile memory for storing the FG signal target cycle data of the motor; and output data of the cycle measuring means and the Comparing means for comparing the FG signal target cycle data stored in the non-volatile memory and outputting the comparison result, and motor control for controlling the rotation speed of the motor in the direction in which the comparison input is matched according to the comparison result of the comparing means. And a magnetic tape running device. 2. A second cycle measuring means for measuring a cycle of a reproduction output signal of a magnetic tape on which a reference signal is recorded, and a difference between a cycle of the reference signal and a cycle of the reproduction output signal. 2. The magnetic tape running device according to claim 1, further comprising a calculation unit for calculating a FG signal target period of the motor, and storing a calculation result of the calculation unit in a non-volatile memory.