JPS61188791A - Magnetic tape regenerator - Google Patents

Abstract

PURPOSE:To find out an expected position for a magnetic tape without equipping a fixed head by seeking for tape positions through a constant regeneration after a difference between the tape position and moving target becomes less than a fixed value. CONSTITUTION:In the case where the position difference between the existing position of tape and moving target is larger than the fixed value DELTAT by inputting the expected position of tape through a moving target inputting measure 14, the tape position information is read by allowing the magnetic tape to take a tape speed of normal regeneration again after sending its magnetic tape at a high speed for an instant time and then the tape is movable comparatively swiftly to nearby the expected moving target position by repeating a process of comparing the above information with the moving target of moving target input means 14. Once the difference between the moving target of the above input means 14 and a position memory 13 showing an existing position becomes less than the fixed value DELTAT, the magnetic tape 2 is run and driven at a normal regeneration speed by a capstan axis 19 and automatically detects the correct tape position to be desired, as it reads the tape position information recorded at each track.

Description

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

Conventional technology 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 recorded address signals. (For example, "Video Editing Technology," written by Takeshi Ogawa, published by Kenrokukan Publishing, pp. 43-46) Problems to be Solved by the Invention With such conventional technology, [, CTL signals and address recording on queuing tracks] Therefore, a dedicated fixed head had to be provided.

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 problems, the present invention first uses a magnetic tape with tape position information recorded on a part of a helical track formed on the magnetic tape, and then winds the magnetic tape. two reel stands, a reel drive means for driving the reel stands, a magnetic tape drive means for running the magnetic tape at a constant speed, a destination input means for inputting a destination of the magnetic tape, and a magnetic tape. a position memory that stores the position information read when the vehicle is traveling at a constant speed; a timer that measures a predetermined time; and a position comparator that outputs the difference between the destination input by the destination input means and the value in the position memory. ,
When the output of the position comparator is less than a predetermined value, the reel driving means causes the magnetic tape to run at high speed, the timer is started, and after a predetermined time has elapsed, the magnetic tape driving means moves the magnetic tape again. causing the magnetic tape to travel at a constant speed and storing position information on the magnetic tape in the position memory;
The tape drive control circuit includes a tape running control circuit that causes the magnetic tape drive means to run at a constant speed when the output of the position comparator is smaller than a predetermined value.

According to the above-described configuration, the present invention reads the tape position information recorded on each track during normal playback and compares the movement destination input by the movement destination input means with the tape position stored in the position memory, and calculates this value. When is larger than a predetermined value, high-speed forward forward or backward simultaneous forwarding 9 is performed for a certain period of time, and then normal playback is performed again to read the tape position information and compare it with the destination entered by the destination input means. When the difference between the tape position and the destination becomes smaller than a predetermined value, the magnetic tape position is automatically searched by comparing the magnetic tape position information and the destination using normal constant speed playback. .

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 the head 1a.
, 1 A cylinder for holding b and rotating it at high speed, 2
are magnetic tapes, 3a, sb and 4a are posts for 4-bit tape running guides, 5 and 6 are reel stands 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, 11
10 is a capstan drive circuit for rotating the capstan motor 18 at a constant speed and running the tape 2 at a constant speed. The above is the capstan drive circuit 10.
．． The lensoid 11, the capstan motor 18, the capstan shaft 19, and the pinch roller 2o constitute a magnetic tape drive means.

Reel motors 7 and 8 drive the reel stands 6 and 6, respectively; 9 drives the reel motor 7 or 8 from a command from a tape running control circuit 16 (described later) to move the magnetic tape 2 at high speed and almost This is a reel control circuit for running at a constant speed.

Above is the reel motor 7.8. , the reel control circuit 9 constitutes a reel driving means. Furthermore, 12it, head 11
13 is a position memo 1c that stores the output of the decoder 12; 14 is a destination input means for inputting the destination of the magnetic tape; 17 is a destination input means for inputting the destination of the magnetic tape; 16 is a timer for counting a certain period of time; 16 is a position comparator that takes the difference between the output of the position memory 13 and the output of the destination input means 14; 16 is a tape running control circuit; value(
This value is defined as ΔT. At the same time, the power is turned off and the reel motor 7 or 8 is energized via the reel control circuit 9 to feed the magnetic tape at high speed.

Which of the reel motors 7.8 is energized is determined by which one is larger, the destination of the transfer destination input means 14 or the position memory 13 indicating the current position. Further, when the output of the position comparator 16 is smaller than a predetermined value ΔT, the tape running control circuit 16 generates a winding torque at the normal playback tape speed to the winding reel via the reel control circuit 9. While applying the necessary current, the solenoid 11 is energized to press the pinch roller 20 against the capstan shaft 19, so that the capstan drive circuit 1o and the capstan motor 18 run the magnetic tape 2 at a normal playback speed. Operate. In the low-speed normal playback mode in which the magnetic tape 2 is run by the capstan shaft 19 and the pinch roller 20, the position information recorded on the track can be read, but the magnetic tape 2 is moved when the pinch roller 2o and the capstan shaft 19 are separated. When traveling at high speed by the trolley motor 7 or 8, the position information recorded on the track cannot be read.

With the above configuration, the current position of the tape and the position of the destination can be determined by inputting the desired position of the tape using the destination input means 14 using the device shown in the block diagram of FIG. If the difference is greater than a predetermined value △T, the magnetic tape is fed at high speed for a certain period of time, and then the magnetic tape is set to normal playback tape speed again to read the tape position information and compare it with the destination input by the destination input means 14. By repeating the process, the tape can be moved relatively quickly to near the desired destination position. However, the predetermined value ΔT set in the tape travel control circuit 16 that determines the approachable location must be set to be larger than the amount of tape that the magnetic tape that is being fed at high speed for a certain period of time actually advances. If the difference between the destination of the advance input means 14 and the position memory 13 indicating the current position becomes smaller than the predetermined value ΔT, the magnetic tape 2 is driven to run at the normal playback speed by the capstan shaft 19 as described above. The desired tape position can be automatically searched for accurately while reading the tape position information recorded on each track. "□FIG. 2 shows the main parts of another embodiment of the present invention, in which the reel control circuit 9 is composed of a drive circuit 27, 28 and a current setting circuit 29, 30, and the tape running control circuit 16 is composed of a magnitude comparator 21. ,
Inverter 22, 24, OR circuit 23, AND circuit 26
26, and the movement destination input means 14 is a keyboard 31.
An example is shown in which a destination memory 32 is configured. 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. 1 are omitted. Also,
FIG. 3 shows an example of recording on the magnetic tape 2.
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 SMPTIC standard (standardized in 1970) for video tape recorders.

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

In FIG. 2, the destination tape position is input from the keyboard 31 and stored in the destination memory 32. The difference between the output of the destination memory 32 and the output of the position memory 13 is taken by the position comparator 16 and input to the -=rf magnitude comparator 21. At the same time, the magnitude relationship is input to the AND circuit 25 and the inverter 24. be done. The magnitude comparator 21 compares the input output of the position comparator 16 with a value corresponding to a predetermined value Δ (another input of the magnitude comparator, not shown), and if ΔT is greater than the output of the position comparator 16. If the output is large, the timer 17 is started and a low logic output is made to the OR circuit 23 to turn off the solenoid 11.

Conversely, if the output of position comparator 15 is smaller than △T, timer 1
7 is not activated, and outputs a high logic output to the OR circuit 23 to energize the solenoid 11. The operation in these cases will be explained.

When the output of the position comparator 16 is larger than ΔT, the timer 17 is started, and at that moment the output of the timer 17 becomes a low logic and is passed through the inverter 22 to the AND circuit 25.26.
A high logic input is applied to one input of. Position comparator 1
Among the outputs of 6, the output indicating the magnitude relationship between the position memory 13 and the destination memory 32 is set to be at a low logic level when the output of the destination memory 32 is higher than the other. 26 output is low logic, AND circuit 26
The output of is high logic. For the output of the position memory 13,
When the output of the destination memory 32 is low, the output of the position comparator 15 indicating the magnitude relationship is high logic, the output of the AND circuit 25 is high logic, and the output of the AND circuit 26 is low logic.

The current setting circuit 29.3o is configured to set a large current to provide high-speed rotation to the reel motor 7.8 via the drive circuit 27.8 when both receive a high logic input.
Conversely, when the logic input is low, the setting is such that a small current flows to apply torque to the reel so that the tape does not sag during normal playback.

Therefore, as a result, when the output of the destination memory 32 is larger than the output of the position memory 13 and the output of the position comparator 16 is larger than ΔT, the output of the AND circuit 26, that is, , the input of the current setting circuit 30 becomes high logic, a large current is applied to the reel motor 8, and the magnetic tape is rapidly forwarded in the forward direction. Further, when the output of the destination memory 32 is smaller than the output of the position memory 13, a large current is applied to the roll motor 7, and the magnetic tape is rapidly forwarded in the unwinding direction.

Next, after the timer 17 has elapsed a certain period of time, its output switches from low logic to high logic, and one input of the AND circuit 25 and 26 both becomes low logic via the inverter 22, and the AND circuit The creative power of 25° and 26 are both low logic. At this time, the torque generated by the reel motor 7.8 is a minute torque required for winding the tape during normal reproduction. Further, when the output of the timer 17 becomes high logic, the OR circuit 23
The solenoid 11 is energized via the solenoid 11, the pinch roller 2o shown in FIG. 1 is pressed against the capstan shaft 19, and the magnetic tape runs at a constant speed at the normal playback speed. When the tape position information on the magnetic tape is read during this constant speed running, the contents of the position memory 13 are updated and the above-described process is repeated.

When the magnitude comparator 21 determines that the output of the position comparator 16 is smaller than the set value ΔT, the output of the timer 17 remains high logic, and the current setting circuit 29
．． 30 inputs are both low logic and reel motor 7.8
The torque is set small, and a high logic output is applied to the OR circuit 23 to energize the solenoid 11 so that the magnetic tape runs at the normal playback speed. In this case, the tape can be run while always reading the tape position information recorded on the tracks on the magnetic tape, so operations such as stopping at a desired tape position or playing music from a desired tape position can be performed. I believe it is possible.

Therefore, by inputting the tape position to be moved using the keyboard 31, the magnetic tape is automatically fed close to the target movement position by intermittently feeding the magnetic tape at high speed.
After that, you can read the tape position information during normal constant speed playback and 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 the magnetic tape position where the desired music or video is recorded without installing an extra fixed head. It is extremely effective in practical terms.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a magnetic tape playback device according to an embodiment of the present invention, FIG. 2 is a block diagram showing main parts of a magnetic tape playback device according to another embodiment of the invention, and FIG. 3 is a block diagram showing a magnetic tape playback device according to another embodiment of the invention. It is a figure which shows the above recording example. 2...Magnetic tape, 6,6...Reel stand, 7°8.9...Reel drive means, 10,1
1.18°19, 20...Magnetic tape drive means, 14...Movement destination input means, 13...
・Position memo ic 17... Timer, 16...
...Position comparator, 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 in a predetermined location of each track, the device comprising: two reel stands for winding the magnetic tape; a reel drive means for driving a reel stand; a magnetic tape drive means for causing the magnetic tape to run at a constant speed; a destination input means for inputting a destination for the magnetic tape; a position memory that stores position information; a timer that measures a predetermined time; a position comparator that outputs a difference between a destination input by the destination input means and a value in the position memory; and an output of the position comparator. is larger than a predetermined value, the reel drive means runs the magnetic tape at high speed, starts the timer, and after a predetermined time has elapsed, the magnetic tape drive means runs the magnetic tape at a constant speed again. The present invention further includes a tape running control circuit which stores position information on the tape in the position memory and causes the magnetic tape drive means to run at a constant speed when the output of the position comparator is smaller than a predetermined value. Features of magnetic tape playback device.