JPH0227747B2 - JIKITEEPUKUDOSOCHI - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] When a new tape (unmeasured tape) is attached, this invention measures the optimal motor supply power value for that tape, and then runs the tape again. In other words, when recording information on this tape (measured tape) or reproducing it, a magnetic tape drive is designed to run the tape stably based on the measured power value. Regarding equipment.

[Prior Art] In recent years, magnetic tape devices connected to computers and the like have been required to have a large storage capacity, and along with this, the recording density when recording information on magnetic tape has gradually become higher. Therefore, it has become necessary to make the running speed of this magnetic tape more stable.

FIG. 3 is a partially cutaway plan view showing a cartridge magnetic tape used in such a device and a part of a mechanism for driving this cartridge magnetic tape. As shown in this figure, this cartridge magnetic tape 1 is driven by a motor. When the motor capstan 3 is rotated by the motor capstan 2, the cartridge magnetic tape capstan 4 in contact with the motor capstan 3 rotates, and the cartridge magnetic tape capstan 4 and the first , a constant tension drive belt 9 stretched between the second rollers 5, 6 and the wound magnetic tapes 7, 8 runs, causing the magnetic tapes 7, 8 to rotate in opposite directions. When the magnetic tapes 7 and 8 rotate in opposite directions, the magnetic tape 10 is unwound from one of the magnetic tapes 7 and 8 and wound around the other magnetic tape.

Incidentally, in such a cartridge magnetic tape, since the friction torque and the moment of inertia of the cartridge magnetic loop are different for each cartridge, it has been difficult to control the tape running speed to a predetermined value. In order to control the tape at a predetermined speed, it is necessary to drive the tape with a large motor having a large driving force that takes into account the cartridge having the largest frictional torque among the respective cartridges.

However, in recent years, recording/playback devices to which such cartridge magnetic tapes are attached have become smaller:
Due to the strong demand for cost reduction, the driving force of the motor cannot be increased, resulting in the problem that it is difficult to stably run the magnetic tape at a predetermined speed.

[Problems to be Solved by the Invention] In view of the above-mentioned circumstances, the present invention makes it possible to move this magnetic tape using a motor with a small driving force even if the frictional torque, moment of inertia, etc. of the magnetic tape are different for each cartridge. It is an object of the present invention to provide a magnetic tape drive device that can run stably.

[Means for Solving the Problems] In order to achieve this object, the magnetic tape drive device according to the present invention includes a tape drive motor so that the running speed of the set magnetic tape becomes a predetermined setting speed. a control means for controlling the power supplied to the magnetic tape; a first storage means for storing, as a measured power value, a power value when the tape speed matches the set speed by the control means; a start-up necessary when starting the magnetic tape; a second storage means that stores a power value as a set power value at every predetermined time; a set power value stored in the second storage means and a set power value stored in the first storage means; and power value determining means for receiving the measured power value and calculating the starting power value to be supplied to the motor at predetermined time intervals, and the set magnetic tape is immediately activated at the time of starting based on the stored measured power value. The vehicle is characterized in that the vehicle travels at the set speed.

[Embodiments] The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1a is a circuit block diagram showing an embodiment of a magnetic tape device according to the present invention. In this figure, the CPU (microprocessor) part is divided into functional blocks. In this figure, 15
16 is a control device having a microprocessor (CPU) that controls each part of the circuit based on various command signals S1a to S1n supplied from a command means (for example, a host computer, an operation panel, a tape attachment detection circuit, etc.); Motor power value supply means 2
7 is a digital/analog converter (D/A converter) that converts the output power value W _D into a voltage signal S2; 17 is a power amplifier that amplifies the power of the voltage signal S2 at a predetermined amplification factor; 18 is the power amplifier 17; is a motor that rotates with a driving force according to the electric power S3 outputted by the controller 15, and the control means 15 controls the electric power value W _D
, the D/A converter 16, the power amplifier, and the motor 18 convert this electric power value W _D into a driving force corresponding to the magnitude of this electric power, and this driving force powers the motor cap attached to the motor 18. The stand 19 rotates and the cartridge magnetic tape 1
The magnetic tape 10 inside is driven to run. Also, 2
0 is a tape speed detecting section that detects the rotational speed of the motor 18, that is, the running speed of the magnetic tape 10, and a rotary encoder 21 connected to the motor 18 and an oscillator 2 that generates a clock signal.
2 and the output of the rotary encoder 21 pass/cut off the output of the oscillator 22 to drive the motor 18.
a pulse train according to the rotational speed of the motor (the number of pulses in this pulse train is inversely proportional to the rotational speed of the motor)
The gate circuit 23 outputs P1. Further, 24 is a tape speed that compares the tape speed Vt indicated by the number of pulses in the pulse train P1 outputted by the tape speed detection section 20 with the set speed Vf outputted from the speed setting section 25 to determine the magnitude thereof. It is a discrimination part, and this discrimination result (Vt>
Vf or Vt=Vf or Vt<Vf) is supplied to the control device 15.

In FIG. 1B, A is a curve showing the correspondence between a predetermined speed and time, and B and C are diagrams showing the corresponding correspondence between the supplied electric power value and time. In the figure, B indicates the set power value that is predetermined at predetermined intervals as the starting power value required when starting the magnetic tape, and C indicates the set power value that is required when the tape is running at a constant speed. It shows.

Note that these power values are determined in advance through experiments and the like, and are stored as set power values in the second storage device (initial power value storage means). The measured power value and the set power value are read out by the power value determining means, and the power to be supplied at the time of starting the actually set magnetic tape is calculated. Then, the set magnetic tape is driven by the calculated power value, and recording or reproducing operation is performed.

Next, the operation of this embodiment configured as described above will be explained with reference to the flowchart shown in FIG.

Now, if a new cartridge magnetic tape 1 is installed in the recording/reproducing apparatus equipped with this circuit, this is detected by the tape installation detection circuit (not shown) and the drive command means 2 of the control means 15
6, motor drive command S1a, measurement mode command S1
b is supplied sequentially (step SP1 in Fig. 2,
(See SP2). As a result, the drive command means 26 supplies the signals S5 and S7 to the motor power value supply means 27 and the speed setting section 25, respectively, to put them into the operating state, and also sends the measurement mode signal S6a to the power value determination means 28 in step SP3. to put it into measurement mode. When the power value determining means 28 enters the measurement mode, the power value determining means 28 reads out the initial power data W _D stored in the initial power value storage means 29 in advance, and this is sent to the motor power value supplying means 27. supplied to As a result, the motor power value supplying means 27 supplies the initial power data W _O to the D/A converter 16 as power data W _D to be supplied to the motor 18, and operates the motor 18 at a speed close to a preset scheduled speed. The magnetic tape in the cartridge magnetic tape 1 is rotated at the initial speed, and the rotary encoder 21 is rotated at this initial speed. and,
When the rotary encoder 21 rotates, a tape speed Vt (pulse train P1) indicating the speed of the magnetic tape is output from the tape speed detecting section 20 provided with the rotary encoder 21, and is supplied to the tape speed determining section 24. here this tape speed
The value of Vt and the set speed Vf output by the speed setting section 25
The result of this determination is supplied to the power value determining means 28. Next, the power value determining means 28 executes steps SP4 and SP5 shown in FIG. 3, and if the value of the tape speed Vt and the value of the set speed Vf do not match, that is, if Vt>Vf,
Subtract a constant value K from the power data W _D , and use the subtraction result (W _D −K) as new power data W _D ,
(See step SP6 in Figure 2), and conversely, Vt<Vf
If so, add the constant K to the power data W _D and use the addition result as new power data W _D (see step SP7). This new power data W _D is supplied to the motor power value supply means 27, and the motor Change the rotation speed of 18. As a result, the tape speed Vt of the magnetic tape approaches the set speed Vf by one step, but if these do not match, the step SP4 described above,
SP6 or steps SP5 and SP6 are executed repeatedly,
These are made to match. If these match, the above-mentioned steps SP4 to SP7 are completed and the next step SP8 is executed, and the power value determining means 2
8 stores the power value data W _D at this time in the measured power value storage means 30 as measured power data W _C. Next, step SP9 is executed, and the power value determining means 28 calculates the magnetic tape 10 based on a predetermined calculation formula (for example, a calculation formula based on constants determined from experiments) from the current power data W _D. The power data _WST necessary for starting the motor and the power data _WSP necessary for stopping the motor are calculated and stored in the measured power value storage means 30, and a drive command is issued in the next step SP10. After the rewinding means 31 of the means 26 rewinds the magnetic tape, the operation of each part of the circuit is terminated.

In this measurement mode, _the magnetic tape is actually run based on the initial power data W _O stored in the initial power value storage means 29 and the power data W _D , and the obtained power is obtained at this time. power data that is finally obtained by correcting the power data W _D until the tape speed Vt of the magnetic tape to be used matches the preset speed Vf;
W _D is stored in the measured power value storage means 30 as measured power data W _C , that is, power data Wc for running the magnetic tape 10 of the currently loaded cartridge magnetic tape 1 at the set speed Vf.

Next, after the above-mentioned measurement mode is executed, the motor drive command S1c is sent to the drive command means 26 and recorded.
When the regeneration commands S1d are sequentially supplied, the drive command means 26 executes steps SP1 and SP2.
Proceed to SP11. In step SP11, first, the drive command means 26 outputs a signal S5 to put the motor power value supply means 27 into an operating state, and also supplies a motor starting command S6b to the power value determination means 28. Thereby, the power value determining means 28 reads out the power data W _ST stored in the measured power value storage means 30 and supplies it to the motor power value supplying means 27 to start the motor 18 . Next, the drive command means 2
6 supplies a constant speed running command S6c to the electric power value determining means 28, and also supplies a signal S7 to the speed setting section 25. As a result, the power value determining means 28 reads the power data W _C from the measured power value storage means 30 and supplies it to the motor power value supply means 27 to rotate the motor 18 with power corresponding to this power data W _C. (Steps in Figure 2)
(see steps SP12), and checks whether the tape speed Vt of the magnetic tape obtained at this time matches the set speed Vf set in the speed setting section 25 (see steps SP13 and 14). If not, the power data W _C is corrected so that these match (see step SP15), and the magnetic tape is stably run at the set speed Vf. Next, in this state, if a recording/reproduction stop command S1 is supplied to the drive command means 26, this causes the drive means 26 to stop.
6 detects this in step SP13, executes step SP16 in the next step, and sets the power value determining means 2.
A motor stop command S6d is supplied to 8.

In this way, the power value determining means 28 reads the power data W _SP from the measured power value storage means 30 and supplies it to the motor power value supply means 27, so that the power value indicated by the power data W _SP corresponds to the time. This motor 18 is stopped based on the data (deceleration rate).

As described above, in the recording/reproducing mode, the power value given to the motor 18 is calculated and determined based on the power data W _C obtained in the measurement mode. In other words, since the cartridge magnetic tape 1 is run using the electric power value obtained in the measurement mode, even if the cartridge magnetic tape 1 has a different friction torque or moment of inertia than the standard one, the magnetic tape 1 can be moved at the set speed.
Stable running at Vf can be achieved without using a motor with large driving force. Moreover, in this embodiment, since feedback is applied during recording and reproduction to constantly correct the power data W _C obtained during measurement, the running speed of the magnetic tape can be made more stable.

Furthermore, in the embodiment described above, when a new cartridge magnetic tape 1 is installed, the measurement mode is automatically set. It is also possible to detect this when the deviation Vt-Vf exceeds a predetermined value, and then automatically enter the measurement mode when recording/reproduction is completed.

Further, in the above description, it has been explained that no feedback is applied when the motor 18 is started and stopped, but the power data W _ST and W _SP may be corrected by applying feedback during these periods.

[Effects] As explained above, when a new magnetic tape is loaded, the magnetic tape drive device according to the present invention performs a test run on this magnetic tape and determines the power value required to run it at a set speed. is measured, and the magnetic tape is driven based on this power value during recording and playback, so even if the frictional torque, moment of inertia, etc. of the magnetic tapes differ greatly from magnetic tape to magnetic tape, the small size, This magnetic tape can be stably run at a set speed using an inexpensive motor.

[Brief explanation of drawings]

FIG. 1a is a block diagram showing an embodiment of a magnetic tape device according to the present invention, FIG. 1b is a time chart for explaining this embodiment, and FIG. 2 is a flowchart for explaining this embodiment. FIG. 3 is a partially cutaway plan view showing an example of a cartridge magnetic tape and a drive mechanism for driving the cartridge magnetic tape. 10...magnetic tape, 15 ...control device, 20
...Tape speed detection means (tape speed detection section),
24... Tape speed discrimination means (tape speed discrimination section), 27... Motor power value supply means, 28...
Power value determining means, 30... Measured power value storage means, 31... Rewinding means.

Claims (1)

[Claims] 1. Control means 15, 2 for controlling the electric power supplied to the tape drive motor so that the running speed of the set magnetic tape becomes a predetermined set speed.
0, 24; a first storage means 30 for storing, as a measured power value, a power value when the tape speed matches the set speed by the control means; a starting power value necessary for starting the magnetic tape is predetermined; a second storage means 29 storing the set power value for each predetermined time period; the set power value stored in the second storage means; and the measured power value stored in the first storage means; and a power value determining means 28 for calculating a starting power value to be supplied to the motor at predetermined time intervals based on the stored measured power value, and immediately adjusting the set speed to the set magnetic tape at the time of starting the magnetic tape based on the stored measured power value. What is claimed is: 1. A magnetic tape drive device characterized in that the magnetic tape drive device is configured to run at 2. The magnetic tape drive device according to claim 1, wherein the control means 15, 20, and 24 have a speed detector and control the tape speed by receiving an output signal from the speed detector. .