JPS6233661B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing device, and particularly to a cueing device thereof.

In general, a cueing device in a magnetic recording/reproducing device is used to drive a tape to a predetermined position and stop it, especially when the tape is moved from a high tape speed state to a stop state, such as when fast forwarding or rewinding the tape. Even if the tape is converted to a predetermined position, it is extremely difficult to stop the tape at a predetermined position due to the inertia of the reel drum. For this reason, conventionally, a cueing device has been proposed which detects the speed of the tape and stops the tape early. However, such devices have many drawbacks, such as the fact that it is not possible to clearly determine where to issue a tape stop command signal depending on the position of the cue point, and the tape may stop after passing a desired predetermined position.

Therefore, the main object of the present invention is to provide a cueing device that eliminates the drawbacks of the conventional devices as described above.The main object of the present invention is to provide a cueing device that eliminates the drawbacks of the conventional devices as described above. Therefore, the tape is stopped at a predetermined position by repeatedly issuing commands such as fast forward, rewind, and stop.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. Fig. 1 shows an electrical system diagram of an example of the cueing device of the present invention. , this designation signal is supplied to the register circuit 2 and stored therein. On the other hand, the feeding amount detecting means 3 synchronized with the feeding of the tape detects, for example, pulses magnetically recorded on the roller, and the detected pulse outputs are applied to the counter circuit 4 and the FM demodulator 7, respectively. 4, an output representing a value corresponding to the position of the tape while it is running is obtained. On the other hand, the pulse from the detection means 3 applied to the FM demodulator 7 is
This converts it into an analog voltage proportional to the tape moving speed. The outputs of the register circuit 2 and the counter circuit 4 are applied to a comparator circuit 5, whereby the tape stop or speed change position is compared every moment with the set position and the current tape running position. The output of the comparator circuit 5 is added to the digital-to-analog converter circuit 6, and thereby the comparator circuit 5
Converts digital output to analog value. The output of the conversion circuit 6 and the output of the FM demodulator 7 are applied to an analog comparator circuit 8, where the analog values of the two are compared in magnitude to obtain a low or high output. Furthermore, a digital-to-analog conversion circuit 6
is applied to one input terminal of the comparator circuit 9.
Since a voltage of zero volts is applied to the other input terminal of this comparator circuit 9, the output of the difference between the set position and the current tape running position is equal to zero volts. compared to voltage. Thus, in response to this deviation output, the comparator circuit 9
A higher or lower output can be obtained.

Furthermore, in the present invention, fast forward (FF), rewind (REW), and stop (STOP) signals are obtained by a logic circuit. For this purpose, the outputs of the comparison circuits 8 and 9 and the output of the inverter circuit 19 are added to the AND gate circuit 10, and the fast forward signal is taken out to the output terminal (T _FF ) of the AND gate circuit 10, and the outputs of the comparison circuits 8 and 9 are are added to the inverter circuits 17 and 18, the outputs of the inverter circuits 17 and 18 are added to the AND gate circuit 12 along with the output of the inverter circuit 19, and the rewind output is sent to the output terminal (T _REW ) of the AND gate circuit 12. The outputs of the digital-to-analog conversion circuit 6 and the FM demodulator 7 are applied to the zero-volt detection circuits 13 and 14, respectively, and the outputs of these detection circuits 13 and 14 are passed through the AND gate circuit 15 to the inverter circuit 19.
and one input terminal of the OR circuit 11. Adding the outputs of the AND gate circuits 10 and 12 to the AND gate 16 through the inverter circuits 20 and 21,
The output of this AND gate 16 is added to the other input terminal of the above-mentioned OR circuit 11.
The stop signal is output from the output terminal (T _STOP ) of the terminal.

The operation of the apparatus according to the present invention having the above-described structure will be explained with reference to FIG. 2, which is a graph showing the tape position on the horizontal axis and the voltage level on the vertical axis. For example, the planned position at which the tape is to be stopped is set to point x, and the specified position by key switch 1 is set to x. The current tape position is detected by the tape feed amount detection means 3, and the current tape position y is detected at the specified position x.
A comparison circuit 5 compares the signal with a value proportional to the difference between the two, and a digital-to-analog conversion circuit 6 outputs an analog value as shown by the straight line A in FIG. Now, if this analog value output is positive, the comparator circuit 9 compares this analog output with zero volts and provides a corresponding output. On the other hand, the signal proportional to the tape speed from the FM demodulator 7 is as shown by the straight line RO in FIG. Now, for example, if the reel is in a stopped state, the output from the FM demodulator 7 will be zero. Outputs such as the above-mentioned straight lines A and B are compared by the comparator circuit 8, and corresponding outputs are obtained.

On the other hand, the zero volt detection circuit 13 includes a conversion circuit 6.
The output of the demodulator 7 as indicated by the line A, which is zero at the position y, is supplied as an input to the other zero volt detection circuit 14. The output of the inverter circuit 15 becomes "0", and the output "0" becomes "1" in the inverter circuit 19 and is applied to the AND gate circuit 10. Therefore, since the signals "1", "1", "1" are input to the AND gate circuit 10,
A fast-forward signal is output to the fast-forward terminal (T _FF ).

This fast-forward signal accelerates the reel (not shown), and the output of the FM demodulator 7 gradually rises from the zero volt state, and the voltage increases as shown by the straight line B in FIG. , a constant voltage value.
On the other hand, the voltage level of the output from the digital-to-analog conversion circuit 6 decreases as it approaches the setting position x, as shown by straight line A in FIG. 2, and reaches point z, which matches the voltage shown by straight line B. reach. After passing this point z, the output shown by straight line B becomes larger than the output shown by straight line A. Therefore, the AND of the AND gate circuit 10 is not satisfied and no output is produced, so the fast-forward output signal is cut off and a stop signal appears at the stop output terminal (T _STOP ). Therefore, the brake is applied to the reel and the reel comes to a stop. At this time, the voltage levels shown by straight lines A and B are reversed, and a fast-forward signal appears. The operation as described above is repeated during the repetition period C between points z and x, the reel is decelerated toward the setting position The AND of the gate circuit 15 is established and only a stop signal is generated (FIG. 2 FF,
(see STOP), the tape stops at a predetermined position, that is, the setting position x. It is clear that if the setting position is in the negative direction of the current position y, a signal is output to the rewind terminal ( _TREW ).

In the embodiment of the present invention described above, the output is obtained by switching between fast forward and stop, but by rearranging the logic circuit, it is possible to stop at the setting position x by switching between fast forward and rewind. It is also possible to take out a signal, and the comparator circuit 8 uses the output of the digital-to-analog conversion circuit 6, but it is of course possible to use a digital comparator circuit that directly uses the output of the comparator circuit 5. In this case, it goes without saying that the digital-to-analog conversion circuit 6 is unnecessary.

According to the present invention, as described above, it is possible to quickly locate the target position x, and the present invention can be applied to a magnetic recording/reproducing device or the like without a cueing device by simply providing a detection means. , which allows for extremely easy cueing.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of the present invention, and FIG. 2 is a waveform diagram for explaining its operation. In the figure, 1 is a key switch, 2 is a register circuit, 3 is a tape feed amount detection means, 5, 9, and 8 are comparison circuits, and 6 is a digital-to-analog conversion circuit.

Claims (1)

[Claims] 1. In a magnetic recording and reproducing device that fast-forwards or rewinds a tape to set it at a specified position and cue the tape, there is a detecting means for detecting the running state of the tape, and a specifying means for setting the tape at the cue position. , an analog value output means that compares designated position information designated by the designation means and outputs an analog amount proportional to the amount of positional deviation; and detects tape speed information from the output of the detection means and outputs an output according to the speed. speed information detection means for comparing the output of the speed information detection means with the output of the analog value output means; and speed information detection means for comparing the output of the speed information detection means with the output of the analog value output means; tape drive means for decelerating and stopping the speed, and when the running position of the tape approaches the specified position, the comparison means compares the output of the analog value output means with the output according to the speed of the speed information detection means. A cueing device is characterized in that it outputs a comparative output before the tape cue setting position attenuated, decelerates the tape running speed, and stops the tape at the specified cueing position.