JPS61187182A - Magnetic tape reproducing device - Google Patents

Abstract

PURPOSE:To automate the movement of a magnetic tape by running a magnetic tape at high speed when a destination of a destination input means differs largely from a prescribed value in a position memory and switching the tape running when the difference between the output of a running counter and the destination is a prescribed value or below. CONSTITUTION:A tape running control circuit 16 calculates a difference between an output of a destination input means 17 and the sum of outputs of a position memory 14 and the running counter 15 and when the difference is larger than a preset value, a current of a solenoid 13 is cut off to detach a pinch roller 20 from a capstan shaft 19, a command is sent to a reel control circuit 11 to allow a reel motor 7 or 8 to feed the tape at high speed. When the difference between the output of the means 17 and the sum of outputs of the memory 14b and the counter 15 is smaller than a preset value, the speed is switched into low constant running via the relay control circuit 11. Thus, no unnecessary fixed head is given and the movement of the tape to the desired tape position is automated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tape position searching device such as a rotary head type digital audio tape recorder.

BACKGROUND OF THE INVENTION In conventional tape recorders and video tape recorders, when searching for the tape position where desired music or video is recorded, it is necessary to count the CTL signals recorded by a fixed head, or to count the CTL signals recorded by a fixed head. This has been done by reading address signals recorded in (for example.

"Video Editing Techniques", written by Takeshi Ogawa, published by Kenrokukan Publishing, p.43~
P46) Problems to be Solved by the Invention In such conventional techniques, a fixed head had to be dedicated for recording CTL signals and addresses on cue tracks.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a magnetic tape reproducing apparatus that can search for a desired magnetic tape position without a fixed head.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention first uses a magnetic tape in which tape position information is recorded on a part of a helical track formed on the magnetic tape, and generates a signal corresponding to rotation. two reel stands for winding a magnetic tape, in which rotation signal generators each generating a rotational signal are mounted on the same rotating shaft, a reel driving means for driving the reel stands, and a magnetic tape for running the magnetic tape at a constant speed. a driving means, a destination input means for inputting a destination of the magnetic tape, and a position memory for storing the position information read when the magnetic tape runs at a constant speed;
a running counter for calculating a tape running distance from the tape running speed and running time by the reel driving means; and the reel driving means when the difference between the destination of the destination input means and the value of the position memory is larger than a predetermined value. and a tape running control circuit which causes the magnetic tape to run at high speed and switches the running of the magnetic tape to the magnetic tape driving means when the difference between the output of the running counter and the destination becomes smaller than a predetermined value. It is said that

According to the above-described configuration, the magnetic tape is fed at high speed until the difference between the destination manually input by the destination input means and the tape position calculated by the travel counter becomes equal to or less than a predetermined value. The magnetic tape runs at a constant speed, albeit at a low speed, and the magnetic tape position information is accurately read to automatically search for a desired magnetic tape position.

Embodiment FIG. 1 is a block diagram showing an embodiment of the magnetic tape reproducing apparatus of the present invention. In FIG. 1, 1 is head II!
L, 1b'jz cylinder for holding and rotating at high speed; 2 is magnetic tape; 3a, 3b and 4&, 4b are posts for tape running guide; 6 and 6 are reels on which the tape reel for winding tape 2 rides. 18 is a capstan motor, 19 is a capstan shaft, 20 is a pinch roller, 1
3 is a solenoid for pressing the pinch roller 2o against the capstan shaft 19; 12 is a capstan drive circuit for rotating the capstan motor 18 at a constant speed to cause the tape 2 to run at a constant speed. Above, capstan drive circuit 1
2. Solenoid 13. Capstan motor 18. Capstan shaft 19. The pinch roller 20 constitutes magnetic tape driving means.

Further, 7 and 8 are reel motors that drive the reel stands s and el, respectively, and 9 and 1o are rotation signal generators (hereinafter referred to as FG) that are coupled to the reel motor 7 and 8 and output rotation signals.
, 11 is the output of Fe2.10 and the tape running control circuit 16
This is a reel control circuit for driving the reel motor 7 or 8 according to a command (to be described later) to run the magnetic tape 2 at high speed and at a substantially constant speed. As described above, the reel motor 7.8 and the reel control circuit 11 constitute the reel driving means. Furthermore, 14a is a decoder that decodes the output signals of the heads 1a and 1b to read tape position information, and 14t
) is a position memory for storing the output of the decoder 141L, 1
7 is a destination input means for inputting the destination of the magnetic tape; 1°6 is a travel counter for counting the travel time of the magnetic tape; 16 is a tape travel control circuit; and position memory 14.
The difference between the sum of the data of the output of b, the output of the traveling counter 15, and the output of the destination input means 17 is taken, and when the difference is larger than a predetermined value, the current of the solenoid 13 is cut off and the pinch roller is turned off. 2o from the capstan shaft, a command is sent to the reel control circuit 11, and the reel motor 7 or 8 feeds the tape at high speed.

The selection of the reel motor 7 or 8 is determined by the sum of the output of the destination input means 1T, the position memory 14b, and the travel counter 16. Further, when the difference between the output of the destination input means 1a and the sum of the position memory 14b and travel counter 16 becomes smaller than a predetermined value, current is applied to the solenoid 13 to cause the pinch roller 20f and the capstan shaft 19 to flow. At the same time, the reel motor 7 is pressed via the reel control circuit 11.
The torque at 8° is reduced and the magnetic tape 2 is controlled to run at a constant speed at a low speed. The magnetic tape 2 is attached to the capstan shaft 19
When the heads 11L and 1b are run by the magnetic tape, the heads 11L and 1b perform normal running, completely on-tracking the tracks on the magnetic tape, and are in a state where they can read position information on the tape.

As described above, by using the apparatus shown in the block diagram of FIG. 1, by inputting a desired position of the tape through the movement destination input means 17, the tape is run at high speed to the vicinity and normal playback is performed from the nearby tape position. This makes it possible to automatically search for a desired tape position while accurately reading tape position information from the track.

FIG. 2 shows a main part of another embodiment of the present invention, in which the reel control circuit 11 includes drive circuits 30 and 31° switches 32.
．． Adder 21. Consists of F-V converter 22.23,
The tape running control circuits 1 and 6 are composed of an adder 26 and a comparator 24, the destination input means 17 is composed of a keyboard 27 and a destination memory 26, and the running counter 1 is composed of an oscillator 28 and a counter 29. An example is shown below. In FIG. 2, parts having the same functions as those in FIG. 1 are given the same numbers, and parts that are exactly the same as in FIG. Further, FIG. 3 shows an example of recording on the magnetic tape 2, where 31 indicates a track and 34 indicates recorded tape position information. This tape position information can be considered to be something like a time code defined in the SMFTIC standard (standardized in 1970) for video tape recorders.

In the SMPTI standard, a time code is inserted in the vertical synchronization section of a video signal, so naturally the recording position of the tape position information within the track is determined, but the tape position information in the present invention is not restricted by the SMPTIE standard, and can be determined at any track position. Needless to say, it is good to be in

In FIG. 2, the destination tape position is entered on the keyboard 27 and stored in the destination memory 26, and a signal is generated to clear the counter 29 when the input to the destination memory is completed.

The counter 29 counts the pulses output by the oscillator 28 to count time. The output of the counter 29 is the position memory 14
The output of b is summed with the adder 26 and input to the comparator 24. The comparator 24 outputs the output of the adder 26 and the destination memory 2.
6, and when the difference is greater than a predetermined value and the value in the destination memory is larger, the switch 32 is activated by the drive circuit a1.
Connect to the side to feed the tape in the forward direction and solenoid 1
3 is turned off, and color/return 29 is used as an addition type abpe counter. Also, compared to the output of the adder 26, the destination memory 2
When the output of the switch 6 is small, the switch 32 is connected to the drive circuit 3o side to feed the tape in the reverse direction, and the solenoid is turned off, and the counter 29 is set as a subtraction type down counter. Further, when the difference between the output of the adder 26 and the destination memory is smaller than a predetermined value and the destination memory is larger, the switch 32 is connected to the drive circuit 31 side and the adder 21 is connected to the drive circuit 31 side. The output signal is reduced to set the reel motor 8 to the winding torque for normal running, and the solenoid 13 is energized to run the magnetic tape at a constant speed during normal playback.

When the difference between the output of the adder 25 and the destination memory is greater than a predetermined difference and the value of the destination memory is greater than the output of the adder 26, the switch 32 is connected to the drive circuit 31 side. A voltage proportional to the output signal period of Fe2.10 attached to the reel stand is obtained by the y-v converter 22.23 and added by the adder 21, and the drive circuit 31 makes the output of this adder 21 constant. Therefore, the magnetic tape 2 runs at a substantially constant speed without changing its tape speed greatly depending on the winding position. When the output of the destination memory is larger than the output of the adder 26, the switch 32 is connected to the drive circuit 30 side, but the tape running control is almost the same, and the tape speed is almost constant.

With the above configuration, the counter 29 is first cleared for the output of the destination memory 26 inputted from the keyboard, so it is compared with the output of the position memo IJ 14b, and it is determined whether the magnetic tape should be moved forward or not. It is determined by the comparator 24 whether to unwind the winding, and depending on the result, the switch a is
2, solenoid 13, and adder 21 are controlled.

Since the tape speed is kept almost constant by the reel control circuit 11 whether the magnetic tape is advanced or rewound, the running distance of the tape can be estimated simply by counting the oscillator 2B with the counter 29 and measuring the time. An adder 2 adds the sum of the output of the counter 29 and the output of the position memory 14b.
6, the approximate current position of the magnetic tape is calculated, and by constantly comparing it with the destination memory 26, the tape can be fed at high speed close to the destination tape position. Then, when the difference between the output of the destination memory 26 and the output of the adder 25 becomes smaller than a predetermined value, the solenoid 13 is energized to switch to low-speed constant-speed travel using the capstan, and the magnetic tape is While reading the tape position information recorded on the track, the position memory 14b
The magnetic tape can be run while updating the contents of , clearing the counter 29, and comparing the values in the destination memory 26 and the position memory 14b.

That is, by inputting the desired tape position on the keyboard 27, the tape is automatically run at high speed to the vicinity, and then the tape position information can be read during normal constant speed playback to accurately find the destination tape position. .

Effects of the Invention As described above, according to the present invention, the magnetic tape can be automatically moved to a desired magnetic tape position without installing an extra fixed head, and is extremely effective in practice. be.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a magnetic tape reproducing device according to an embodiment of the present invention, FIG. 2 is a block diagram showing main parts of a magnetic tape reproducing device according to another embodiment of the present invention, and FIG. 3 is a block diagram showing a magnetic tape reproducing device according to another embodiment of the present invention. It is a figure which shows the above recording example. 2...Magnetic tape, 9,10...Rotation signal generator%5,6...Reel stand, 7,8.1
1... Reel drive means, 12, 13.1g, 1
9.20...Magnetic tape drive means, 17...
...Movement destination input means, 14kl...Position memory, 15...Travel counter, 16...Tape travel control circuit.

Claims (1)

[Claims] A device for reproducing a magnetic tape in which information is recorded by forming tracks in a helical shape, and tape position information is recorded at a predetermined location on each track, and a rotation signal generator that generates a signal corresponding to each rotation. two reel stands for winding a magnetic tape, each of which is mounted on the same rotating shaft; a reel drive means for driving the reel stand; a magnetic tape drive means for running the magnetic tape at a constant speed; A destination input means for inputting a destination, a position memory for storing the position information read when the magnetic tape runs at a constant speed, and a travel counter for calculating the tape travel distance from the tape travel speed and travel time by the reel drive means. and when the difference between the destination of the destination input means and the value in the position memory is greater than a predetermined value, the reel drive means causes the magnetic tape to run at high speed until the difference between the output of the travel counter and the destination reaches a predetermined value. 1. A magnetic tape playback device comprising: a tape running control circuit that switches the running of the magnetic tape to the magnetic tape drive means when the value becomes smaller than the value of .