JPS61150178A - Reproducing device - Google Patents

Abstract

PURPOSE:To perform a rapid search mode by running a tape at a high speed when position information is not fetched and selecting a further searching sped in accordance with the position information. CONSTITUTION:When a searching mode is selected by an input device 22, a judging control circuit 16 judges that the position information including a tape length and a sub-code based on the rotation, etc. of reels 1, 8 through an arithmetic unit 19 is not fetched then a tape 2 runs through a system controller 23 at such a high speed as 16 times as high as a standard speed. From the fetched position information, correspondingly to the outside of a predetermined range or an inside thereof from a tape end, the tape is run at such a high speed as 200 times or 100 times as high as the standard speed. A tape search is executed a speed by wick traverse or a rewind under a circumstance that the tape stop at the tape end is surely performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a playback device, and is particularly useful when applied to a rotary head type digital audio tape recorder.

BACKGROUND OF THE INVENTION Digital audio tape recorders currently under development include fixed head systems and rotating head systems. The fixed head method uses a multi-track fixed head to record signals on many tracks parallel to the tape's longitudinal direction, while the rotating head method records signals in the tape's longitudinal direction by helical scanning using a rotating head. In this method, signals are recorded on oblique tracks.

When recording an audio signal (or other information) with a digital audio tape recorder, a PCM audio signal is recorded, as well as a subcode containing position information such as a program number and time code. . Based on this subcode, the tape position can be known during playback, and the beginning of the tape can be found using the search mode.

In the digital table recorder using the rotary head method, the tape runs at a speed about 300 times the standard speed in the FF/REW mode (fast forward 7 rewind mode). Also, when in search mode, the tape is at standard speed 20
It travels at variable speeds between ~200x and around 200x. still,
The FF/RBW mode and search mode are performed by driving the reel motor with the pinch roller separated from the capstan.

In a digital tape recorder using a rotating head, immediately after tape loading is completed, or immediately after the power is turned on with the tape loaded, the tape is stopped and the total length and current position of the tape, contents of subcodes, etc. is unknown. Immediately F in this state
When the F/REW mode or search mode is set, the tape runs at a high speed of 300 times or 200 times. At this time, if the tape is located close to the tape end, applying the brake at the desired position will not be enough, and the tape will run from a high-speed running state to the end of the leader tape and then stop abruptly. As a result, an impact is applied to the tape and the tape is damaged.

In addition, the connection part between the leader tape and the magnetic tape has a 10
There is a level difference of approximately 0 μm, and when this level difference passes the rotary head at high speed, the head chip of the rotary head protrudes from the rotating drum by approximately 20 μm, so an impact is applied to the head chip and the head chip is damaged.

As a countermeasure for this, if the FF/REW mode or search mode is set when the total length, position, subcode, etc. of the tape are unknown, first set the tape to FWD mode and run it at the standard speed, and then collect the necessary data. If it is determined from the data that the tape is near the end of the tape, a method is usually considered to prevent high-speed running.

Problems to be Solved by the Invention In order to know the current position of the tape, the rotational speed of the supply reel and the rotational speed of the take-up reel are generally detected by FC, respectively.
It is obtained by performing calculations based on the detected values. However, in order to reduce the error, the detection time is long, and the tape speed is particularly slow at 7.2 m/sec.
A detection time of about 15 seconds is required. For this reason, FF/RE
The inherent high-speed performance of the W mode or search mode cannot be fully utilized, and these modes cannot be executed quickly.

Means for Solving the Problems In the embodiment of the present invention, when the FF/REW mode or search mode is set in a state where the tape position is unknown, the tape is first run at, for example, 16x speed, and during this time When the necessary data is acquired and it is determined from the data that the tape is near the tape end, FF/REW or search is performed at, for example, 100x speed, and it is determined that the tape is far from the tape end. When this occurs, the vehicle is immediately run at 200x or 300x speed and FF/REW or search is performed.

The time to capture the action data is shortened, and even if the tape is FF/REWed or searched from near the tape end,
If it can be stopped at the tape end and is located far from the tape end, .

FF/REW or search can be performed quickly by taking advantage of the original high-speed performance.

Embodiment FIG. 1 shows a reproducing circuit according to the present invention for a digital tape recorder using a rotary head type.

In the figure, a tape 2 unwound from a supply reel 1 is wound at a predetermined angle around a rotating drum 5 equipped with a rotating head 3.4, then passed between a pinch roller 6 and a capstan 7, and then wound. It is wound onto a take-up reel 8.

The take-up reel 8, capstan 7, drum 5, and supply reel 1 are driven by a reel motor M1, a capstan motor Mz, a drum motor, and a reel motor M4, respectively. Further, the pinch roller 6 is driven by the plunger P.

The signals alternately reproduced by the head 3.4 are sent to the amplifier 9.1.
After being amplified by 0, the signal is taken out via a switch 11 that is switched in synchronization with the rotation of the heads 3 and 4, and is further applied to a PLL circuit 13 via an amplifier 12. The playback signal synchronized by the PLL circuit 13 is sent to the PCM decoder 1.
4 and subcode decoder 15 and is decoded based on the clock supplied from the PLL circuit 13.

The data decoded by the subcode decoder 15 is sent to the judgment control circuit 16 and also to the display circuit 17, where the tape position and the like are displayed.

The rotation of the supply reel 8 is detected by the rotation detector 18, and the detected value T7 is sent to the arithmetic unit 19.

Further, the rotation of the take-up reel 1 is detected by a rotation detector 20, and the detected value T is sent to the arithmetic unit 19. The arithmetic unit 19 calculates the detected value T under the condition that the tape speed is constant.
7. Based on Ts, the total length of the tape 2 and the current position of the tape 2 are calculated and sent to the judgment control circuit 16. The input device 22 provides the judgment control circuit 16 with instructions based on operations such as operation buttons of the tape recorder. The judgment control circuit 16 judges the necessary operation based on the supplied data and sends an instruction signal to the system controller 23. The system controller 23 operates each motor stand, ~M, according to the instructed operation.
4 and plunger P.

Next, operations related to the present invention will be explained with reference to the flowchart of FIG.

In step (2), when the FF/REW or search mode is set by pressing the FF button, REW button, or search mode button of the input device 22, first, in step (2), the total length and position of the tape, subcode, etc. It is checked whether various data have already been imported. As mentioned above, the above data is not captured immediately after tape loading is completed, or immediately after the power is turned on while loading has been performed. If data has not been captured, proceed to step (2) and run the tape at 16x speed. At this time, the pinch roller 6 is brought into contact with the capstan 7 to control the tape at a constant speed of 16 times. The running direction at this time is the direction instructed in the FF/REW mode or search mode. In this state, in step (2), the acquisition of the above data is started. That is, the total length and current position of the tape are determined based on the detected rotation values rt and Ts of the supply reel 1 and the take-up reel 8, and the tape speed, and the subcode is read. The relative speed may be within a range in which the data playback speed does not exceed the lock range of the PLL circuit 16, and therefore the tape speed may be other than 16x speed. This data acquisition is completed in about 1 second.

When it is confirmed in step (2) that data capture has been completed, the process proceeds to step (2), where the captured data is examined to determine whether the tape position is within a predetermined range from the tape end. Note that even if data has been captured in step (2), proceed to this step (2).If the tape position is not within the above-mentioned predetermined range in step (2), proceed to step (2) and perform the normal F F
/Execute REW mode or search mode. At this time, the tape is fed at high speed by the reel motor with the pinch roller 6 released. The tape speed is, for example, 300 times the speed in the FF/REV mode, and is variable between, for example, 20 to 200 times the speed in the search mode.

When the position of the tape is within the above-mentioned predetermined range, the process proceeds to step (2), where the tape is run at, for example, 100 times the speed by the reel motor feed, and FF/REW or search is executed.

According to the above, when proceeding to step
/REW or search can be performed. Therefore, the tape can be sent to a desired position in an extremely short time by making full use of high-speed performance. Furthermore, when proceeding to step (2), the vehicle travels at a high speed slower than the maximum speed mentioned above, so even if the brake is applied at a desired position, the vehicle will arrive in time and will not pass the end of the tape. Therefore, damage to the tape or head can be prevented.

Although it is possible to record the absolute position on the tape using subcodes, this is actually only possible for recorded tapes such as music tapes.
Users cannot be expected to record absolute positions. Therefore, when determining the tape position, it is more reliable to determine it from the rotation of the reel. To determine the position of the tape, first the total length of the tape is determined, and then the current position is determined based on that. However, it is not necessary to know the total length of the tape accurately, and the approximate position on the tape may be determined.

Incidentally, the present invention may be applied to the digital tape recorder using the above-mentioned fixed head system.

Effects of the Invention Even if the high-speed mode is set in a state where the tape position information is unknown, the tape position can be detected in a short time, so based on the detected position information, for example, step Alternatively, by controlling the tape as shown in (3), it is possible to quickly execute a high-speed mode that takes full advantage of the high-speed performance, and it is also possible to reliably prevent damage to the tape and head.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a flow chart showing the operation of the present invention. In addition, in the symbols used in the drawings, 1.
・−・・−・−−−−− Tape 3.4−・・−・−・
・−・・One rotation head 8−−−−−−−−−−−−・
······················································································································································································−·
--- Judgment control circuit 18.20 -------------------------------------------------------------------] computing device 22 −−−−−−−−−−−−−
~------Human power device 23・-------1------
------・It is a system controller.

Claims (1)

[Claims] In a reproducing apparatus for reproducing a recording medium on which a digital signal is recorded, a detection means for detecting the position of the recording medium based on rotation of a reel around which the recording medium is wound;
a first high-speed running means for running the recording medium at a first high speed;
a second high-speed traveling means that causes the vehicle to travel at a second high speed slower than the high speed of the first high-speed traveling means; A reproducing apparatus characterized in that a traveling means is operated to cause the recording medium to travel at the second high speed, and in this state, the position information is detected by the detecting means.