JP3520710B2 - Magnetic tape recording / reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape recording / reproducing apparatus for recording / reproducing information using a magnetic tape, and more particularly to improving operability of the apparatus.

[0002]

2. Description of the Related Art In a device for driving a tape by a reel, it is necessary to detect a total tape winding amount, which is a value based on a sum of axially projected areas of a tape wound on a take-up reel and a delivery reel and a reel hub. is necessary.

For example, Japanese Patent Application Laid-Open No. 63-302454 discloses a basic method for realizing this.

[0004]

In a device that drives a magnetic tape by a reel without using a means for directly detecting the tape speed such as a capstan or a timer roller, in order to accurately control the tape speed and the tape tension,
It is necessary to detect the winding diameter of the take-up reel or the delivery reel in real time. The reel diameter is

[0005]

[Equation 1]

Is calculated by Here, r (t) is the winding diameter of the take-up reel, T (t) and T (s) are values based on the rotation cycle of the take-up reel and the delivery reel, respectively, and S is the total tape winding amount.

The total tape winding amount is calculated by using the winding diameter of the take-up reel or the delivery reel at any time. That is, once the winding diameter of the take-up reel or the feeding reel is detected and the total tape winding amount is calculated at an arbitrary time point, the winding diameter can be detected in real time by using the total tape winding amount thereafter. The winding diameter of the take-up reel or the delivery reel for detecting the total winding amount of the tape has been conventionally detected by the following method. One is to run the tape without winding the tape around the take-up reel or the take-out reel, and use the rotation amount of the take-up reel and the take-out reel and the known reel hub radius.

[0008]

[Equation 2]

It is a method to obtain more. Where n (t), n (s)
Is the number of rotations of the take-up reel and the delivery reel,
r (t) and r (s) are the winding diameters of the take-up reel and the delivery reel, respectively, and Td is the tape thickness.

One is based on the length of the tape pulled out from the reel when the tape is loaded and the number of rotations of the reel.

[0011]

[Equation 3]

This is a method of calculating the winding diameter of the reel.
Here, L is the length of the tape pulled out at the time of loading.

However, in the latter method, the length of the tape to be pulled out varies depending on the device or the operation, and the accuracy of detecting the winding diameter deteriorates. Further, when the tape path itself changes due to the tape buffer such as the tension sensor, the detection accuracy becomes worse.

On the other hand, the former method can detect the total tape winding amount with high accuracy. However, the detection position of the total tape winding amount is limited to the tape front end position or the tape end position. For this reason, when a cassette in a state where the tape is wound around both reels is inserted, the tape is sent to the tip position or the end position with the reel winding diameter unknown.
Since the tape speed cannot be detected during this period, the tape must be run at a low speed that allows the tape to be stopped immediately after the end of the tape is detected. As a result, there is a problem that the preparation time after inserting the cassette becomes long.

An object of the present invention is to detect the total tape winding amount with high accuracy and in a short time to improve the tape life and the reliability of the apparatus.

[0016]

In order to solve the above problems, the present invention detects the total tape winding amount accurately and in a short time even when a cassette in which tapes are wound on both reels is inserted. Configure to do.

The above equation (2) is derived from equations (6) and (7). If the tape is run while the tape is not wound on the take-up reel, the tape movement amount of the take-up reel and the delivery reel is

[0018]

[Equation 6]

[0019]

[Equation 7]

[0020] Since the amount of tape movement on both reels is the same, r (s) is derived. Where L (t) is the tape movement amount of the take-up reel, r (t) is the winding diameter of the take-up reel when the cassette is inserted, Td is the thickness of the tape, n (t) is the number of rotations of the take-up reel, and L (t) is (s) is the tape movement amount of the delivery reel, r
(s) is the winding diameter of the delivery reel when the cassette is inserted, and n (s) is the number of rotations of the delivery reel. N (t), n (s), Td, and r (t) are known numbers when the tape is not wound on the take-up reel, but when a cassette in the middle of winding is inserted, r (t) Becomes an unknown number, and r (s) cannot be calculated only by equation (2).

Therefore, a mathematical expression regarding the winding diameters of both reels is further added to perform the calculation.

First, as in the case of the equation (2),

[0023]

[Equation 8]

[0024]

[Equation 9]

[Mathematical formula-see original document] Further, as a mathematical formula, from the rotation cycle or rotation speed information of both reels obtained when the tape is run,

[0026]

[Equation 10]

To obtain Here, T (t) and T (s) are rotation period information of the take-up reel and the delivery reel immediately after the tape is inserted, and n1 (t) and n1 (s) are rotation number information immediately after the insertion of the tape.

From equations (8), (9) and (10),

[0029]

[Equation 4]

Thus, r (s) can be calculated. Equations (8) and (9) are equations obtained when the tape is run in the reverse direction, but r (s) can also be calculated using the equation when the tape is run in the forward direction. Is. In other words, by obtaining the winding diameter ratio of the take-up reel and the delivery reel when the cassette is inserted and the information detected by the tape running after the cassette is inserted, even if the cassette in the mid-winding state is inserted, the total tape winding The amount can be detected.

That is, means for driving the tape, and take-up reel rotation cycle detecting means for detecting information corresponding to the cycle of the frequency signal proportional to the rotation speed of the take-up reel,
Sending reel rotation cycle detecting means for detecting information corresponding to the cycle of the frequency signal proportional to the rotation speed of the sending reel, and a take-up reel detecting information corresponding to the wave number of the frequency signal proportional to the rotation speed of the winding reel A rotation speed detection means, and a delivery reel rotation speed detection means for detecting information corresponding to the wave number of a frequency signal proportional to the rotation speed of the delivery reel,

[0032]

[Equation 4]

And

[0034]

[Equation 5]

And means for detecting the total tape winding amount. Where r (t) is the winding diameter of the take-up reel at an arbitrary point of time, N (0) is the rotation cycle ratio of the feed reel and the take-up reel at the same time point, Td is the tape thickness, and n (s) is the arbitrary value. The rotation speed of the delivery reel obtained by running the tape within a predetermined period from the point of time, and n (t) is the rotation speed of the take-up reel obtained by running the tape within the same period. With this means, even when a cassette in which the tape is not wound at the beginning or the end is used, the total tape winding amount can be accurately detected regardless of the type of recording / non-recording or recording format of the tape, and the operability is improved. Can be improved.

Further, when the tape on which the data is written is used, it is possible to detect the total tape winding amount by using the following means. First, a predetermined value is set as the winding diameter of the take-up reel to run the tape, and the number of tracks traversed by the head during tape running is detected using the envelope. An example of the detected envelope is shown in FIGS. When the tape speed is different from the tape speed during normal reproduction, the envelope becomes a mountain shape, and the number of mountains changes depending on the ratio with the normal speed. The actual tape speed is detected by the ratio of the detected tape speed to the tape speed at the time of data recording, and the detected ratio is converted into the ratio between the winding diameter during running and the correct winding diameter.

That is, the means for setting the winding diameter information of the take-up reel to a predetermined value, the means for controlling the rotation of the take-up reel based on the set predetermined value, the tape running stably, and the tape speed are set. A means for changing the speed to a speed different from that at the time of recording, a means for detecting that the rotary head has crossed the data track recorded on the tape, a means for counting the number of times the data track is crossed, and a winding means based on the counting means. It can also be realized by means for detecting the winding diameter of the take-up reel. This means that when the tape is run at the same speed as it was recorded during playback, the rotary head does not cross the data tracks, but when the tape speed is different, the rotary head crosses the data tracks. It corresponds to the error. With this means, the winding diameter of the take-up reel is unknown and a temporary value is set.Therefore, the difference between the actual winding diameter of the take-up reel and the temporary value is the difference in tape speed, and the number of times the track is crossed. Error occurs. The total winding amount of the tape can be detected by detecting the actual winding diameter based on the number of errors.

In this total tape winding amount detecting method, since the tape travel distance is minute, the detection can be performed in a short time and the operability can be improved.

Further, by providing a means for recording the detected total tape winding amount on the tape, the total tape winding amount can be used when recording / reproducing is performed using the same tape next time. As a result, the total tape winding amount can be accurately obtained in a short time after the cassette is inserted.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION A magnetic tape recording / reproducing apparatus according to the present invention will be described below in more detail with reference to the embodiments shown in the drawings.

A first embodiment of the magnetic tape recording / reproducing apparatus of the present invention will be described with reference to FIG. In FIG. 1, 1 is a tape, 2 is a take-up reel, 3 is a delivery reel, 4 is a take-up reel motor, 5 is a delivery reel motor, 6 is a take-up reel FG detector, 7 is a delivery reel FG detector, 8 is a tape leading edge detector, 9 is a cassette detector, 10 is a take-up reel FG cycle detector, 11 is a delivery reel FG cycle detector, 12 is a total tape amount detector 1, 13 is a take-up reel winding diameter. Calculator, 14 is a winding reel temporary winding diameter value storage memory, 15 is a switch, 1
Reference numeral 6 is a take-up reel drive controller, 17 is a total tape amount detector 2, and 18 is a total tape amount discriminator.

The detector 6 detects an FG signal which is a frequency signal proportional to the rotation speed of the take-up reel, and detects the detected F
The G signal is sent to the detector 10, the detector 12, and the detector 17.
Similarly, the detector 7 detects an FG signal, which is a frequency signal proportional to the rotation speed of the delivery reel, and sends the detected FG signal to the detector 11, detector 12, and detector 17. The detector 10 detects the cycle of the FG signal of the reel 2 sent from the detector 6 using a high frequency clock, and sends the obtained FG cycle to the calculator 13, the controller 16 and the detector 17. Similarly, the detector 11 is the FG of the reel 3 sent from the detector 7.
The period of the signal is detected using a high frequency clock, and the obtained FG period is sent to the calculator 13 and the detector 17.

The detector 9 detects that the cassette is inserted and sends a detection signal to the detector 17. The detector 17 uses the detection signal sent from the detector 9 as a trigger to detect the detector 10.
Then, the cycle ratio of the delivery reel and the take-up reel is calculated from the FG cycle of the take-up reel and the FG cycle of the delivery reel sent from the detector 11. In addition, the FGs sent from the detectors 6 and 7 are counted, and the cycle ratio, the number of FGs on the take-up reel side, and the number of FGs on the delivery reel side are used.

[0044]

[Equation 4]

And

[0046]

[Equation 5]

The total winding amount of the tape is calculated by the above, and the calculated total winding amount is sent to the discriminator 18. Where r (t) is the winding diameter of the take-up reel at any point in time, N (0) is the rotation cycle ratio between the feed reel and take-up reel at the same time point, Td is the tape thickness, and n (s) is
Is the number of rotations of the delivery reel obtained by running the tape within a predetermined period from the arbitrary time point, and n (t) is the number of rotations of the take-up reel obtained by running the tape within the same period. Here, the detection of the total tape winding amount by the detector 17 requires a considerable amount of tape running in accordance with the required detection accuracy. Therefore, there is a case where the tape leading end is detected before the predetermined tape running amount is reached. FIG. 4 shows an example of the detection accuracy of the total tape winding amount detected by the above method.

The detector 8 detects the leading end of the tape and sends a detection signal to the detector 12. The detector 12 uses the detection signal sent from the detector 8 as a trigger to count the number of FGs sent from the detectors 6 and 7 to calculate the total winding amount of the tape, and the calculated total winding amount is determined by the discriminator 18 Send to. Here, the detection of the total tape winding amount by the detector 12 is possible when the tape is rewound to the starting end.

Then, the discriminator 18 sends the calculation result of the earlier sent one of the total tape winding amounts sent from the detector 12 and the detector 17 to the arithmetic unit 13, and outputs the detection end signal of the total tape winding amount to the switch 15. Send to.

The calculator 13 calculates the winding diameter of the take-up reel based on the cycle sent from the detectors 10 and 11 and the total tape winding amount sent from the discriminator 18, and the calculated winding diameter is switched. Send to 15. The memory 14 sends the winding diameter of the take-up reel to the switch 15 as a predetermined fixed value. The switch 15 sends the winding diameter sent from the memory 14 to the controller 16 before the detection of the total tape winding amount, and sends the winding diameter sent from the calculator 13 to the controller 16 after the detection of the total tape winding amount. send. The controller 16 detects the actual speed of the tape based on the FG cycle sent from the detector 10 and the winding diameter information of the take-up reel sent from the switch 15, so that the error between the target speed and the actual speed becomes zero. The drive signal is supplied to the take-up reel motor 4.

As described above, by using the cycle ratio information immediately after the cassette is inserted and the rotational speed information of both reels detected by the tape running thereafter, even when the cassette in the middle winding state is inserted. Detecting the total tape winding amount with high accuracy and without sending the tape to the beginning or end,
Stable tape running can be performed.

In the first embodiment, in the total tape winding amount calculator, the cycle ratio of both reels is calculated from the FG cycle of the feed reel sent from the detector 10 and the detector 11 and the FG cycle of the take-up reel. Although calculated, the present invention is not limited to this. By detecting the number of FGs sent from the detector 6 and the detector 7 in the same period, the cycle ratio of the sending reel and the take-up reel can be detected, and the same degree of accuracy in calculating the total winding amount of the tape can be obtained.

Further, in the first embodiment, the tape speed control is performed using the winding diameter of the take-up reel calculated based on the total tape winding amount, but the present invention is not limited to this. Similar tape speed control can be performed by comparing the information corresponding to the total tape winding amount with the calculation results of the FG cycle information obtained from the take-up reel side and the feed reel side and feeding back the error amount.

Although the detector 17 uses the equation (4), it is usually n (t) >> 1 and n (s) >> 1, and even if the approximate equation is used, the same calculation accuracy can be obtained. it is obvious.

Further, in order to carry out the operations from the mounting of the cassette to the calculation of the total winding amount of the tape in a short time, the tape running speed is considered in consideration of the calculation error of the total winding amount accompanying the increase of the running amount of the tape after mounting the cassette. It is possible to set. In the first embodiment, the total winding amount of the tape can always be detected immediately after running the tape, but the detection error of the total winding amount also changes with the running amount of the tape. Therefore, by gradually detecting the total tape winding amount that becomes highly accurate, and setting the reel winding diameter or tape speed in consideration of the detection error range, it is possible to safely and quickly not reach the tape start end at high speed. The total tape winding amount can be detected and rewound.

The method of detecting the total tape winding amount of the present invention is not limited to the above method. That is, when the signal is already recorded on the tape, the total winding amount of the tape can be detected by changing the tape speed and counting the number of tracks traversed by the rotary head.

A second embodiment of the magnetic tape recording / reproducing apparatus of the present invention will be described with reference to FIG. Since the second embodiment is a modification or addition of a part of the first embodiment, the description will focus on the modified and added elements. 2, 1 is a tape, 2 is a take-up reel, 3 is a delivery reel, 4 is a take-up reel motor, 5 is a delivery reel motor, 6 is a take-up reel FG detector, 7 is a delivery reel FG detector, and 8 is Tape leading edge detector, 9 cassette detector, 10 take-up reel FG cycle detector, 1
1 is a feed reel FG cycle detector, 12 is a total tape winding amount detector 1, 13 is a take-up reel winding diameter calculator, 14
Is a memory for winding reel temporary winding diameter value storage, 15 is a switch, 16 is a winding reel motor drive controller, 17 is a total tape winding amount detector 2, 18 is a total tape winding amount discriminator, 1
Reference numeral 9 is a drum, 20 is a drum FG detector, 21 is a drum rotation speed controller, 22 is a rotary head, 23 is a track crossing detector, and 24 is a crossing track number detector.

The detector 9 detects the insertion of the cassette and sends a detection signal to the controller 16 and the controller 21. The controller 16 detects the detection signal sent from the detector 9, the detection end signal of the total tape winding amount sent from the discriminator 18, and the memory 14.
The tape speed is controlled to be 5 times as high as that at the time of recording, based on the provisionally set winding diameter of the take-up reel. The tape speed described here is a tape speed when it is assumed that the provisionally set winding diameter matches the actual winding reel winding diameter, and is actually a speed corresponding to an error between both winding diameters. There is an error. The detector 20 detects an FG signal, which is a frequency signal proportional to the rotation speed of the drum, and sends the detected FG signal to the controller 21. Controller 21
Is the drum 1 based on the FG signal sent from the detector 20.
It is controlled so that 9 drives at a predetermined rotation speed. The detector 23 detects that the rotary head has crossed a data track on the tape based on the reproduction signal sent from the rotary head 22, and sends a detection signal to the detector 24. The detection signal described here is detected using the envelope detection output of the reproduction signal detected by the rotary head (hereinafter referred to as the reproduction envelope). When the rotary head crosses the reverse azimuth data track, the peak value of the reproduction envelope becomes very small. Therefore, it is detected that the peak value of the envelope is lower than a predetermined threshold value, and the detection signal is sent to the detector 24. send. FIG. 5 is a schematic diagram showing the scanning direction of the rotary head and the envelope of the reproduction signal detected from the rotary head when the tape speed is set to 5 times the recording speed. The detector 24 counts the number of times the rotary head crosses the data track on the tape based on the detection signal sent from the detector 23.
Detect the winding diameter of the take-up reel. The difference between the set provisional value and the actual winding diameter of the take-up reel becomes the difference in tape speed, and this difference becomes the difference between the number of times of crossing the track that should be detected originally and the actual number of times of detection. The actual winding diameter can be detected by the difference in the number of times of crossing. Detector 2
4 sends the detected winding diameter to the detector 17. The winding diameter detection method used here cannot always be used in response to changes in the winding diameter during recording and reproduction. Then, by calculating the total tape winding amount using the detected winding diameter, it becomes possible to detect the winding diameter in real time using the total tape winding amount thereafter.

The operation of the other constituent elements is the same as that of the first embodiment, and will be omitted.

As described above, the tape is run at a speed different from that at the time of recording, the ratio of the number of track crossings to be originally detected and the number of track crossings actually detected, and the winding diameter of the take-up reel set provisionally. By using, it is possible to detect the actual winding diameter of the take-up reel and to detect the total tape winding amount.

In the second embodiment, the tape speed is set to 5 times that at the time of recording, but the present invention is not limited to this. It is possible to detect the winding diameter information of the take-up reel even by making it a multiple of the actual number at the time of recording, and it is possible to obtain the total winding amount of the tape.

Further, the method for detecting the total tape winding amount according to the present invention can be used without depending on the head arrangement, but FIG. 7 and FIG.
In the case of a multi-channel recording / reproducing head as described above, the number of traversing tracks that can be detected increases even with the speed deviation of the same ratio as in the head arrangement shown in FIG. 6, and detection can be performed with higher accuracy. 6, 7, and 8, W is a recording head,
R indicates the reproducing head, and + and − indicate that the azimuth angles are different. The envelope waveform in the case of reproducing at the normal speed does not change in FIGS. 6, 7 and 8, but at the double speed, a mountain-shaped waveform appears. At this time, the peaks where the envelope level detected by one scan of one head becomes large are 1/2, 1 and 2 in the cases of FIGS. 6, 7 and 8, respectively. If the set winding diameter of the take-up reel is equal to the actual winding diameter, a predetermined number of ridges are detected for each head scan, but if there is an error in the set value of the winding diameter, a velocity deviation occurs and the ridge is detected. The number of will also change. Since the number of peaks is detected in units of 1/2, the speed deviation is 5 in each of FIGS. 6, 7, and 8.
It can be detected at 0%, 25%, 12.5% or more. Similarly 5
At double speed, in the cases of FIGS. 6, 7 and 8, 2, 4 and
8 peaks are detected, speed deviation is 20%, 10 respectively
%, 5% or more can be detected.

Further, in the present invention, it is apparent that the accuracy of winding diameter detection improves with the number of times of scanning of the head when detecting the envelope.

Further, the same effect can be obtained by using not only the reproducing head but also the recording head for detecting the envelope.

The method of detecting the total tape winding amount of the present invention is not limited to the above method. By recording the total tape winding amount information on the tape, the total tape winding amount can be obtained accurately in a short time.

A third embodiment of the magnetic tape recording / reproducing apparatus of the present invention will be described with reference to FIG. The third embodiment is a modification or addition of a part of the first embodiment and the second embodiment, so the description will focus on the modified and added elements. In FIG. 3, 1 is a tape, 2 is a take-up reel, 3 is a delivery reel, 4 is a take-up reel motor, 5 is a delivery reel motor, and 6 is a take-up reel F.
G detector, 7 is a delivery reel FG detector, 10 is a take-up reel FG cycle detector, 11 is a delivery reel FG
Cycle detector, 12 total tape winding amount detector 1, 13 take-up reel winding diameter calculator, 14 take-up reel temporary winding diameter value storage memory, 15 switch, 16 take-up reel motor drive controller , 17 are total tape amount detectors 2, 1
Reference numeral 8 is a total tape winding amount discriminator, 19 is a drum, 20 is a drum FG detector, 21 is a drum rotation speed controller, 22 is a rotary head, 25 is a recording / reproducing device, and 26 is a timer.

The recording / reproducing device 25 recognizes an instruction signal for taking out the tape from the external input signal, or recognizes from the timer 26 that a predetermined time has elapsed after the recording operation is completed.
The total tape winding amount information sent from the discriminator 18 is sent to the rotary head 22. The rotary head 22 records the tape total winding amount information sent from the discriminator 18 on the tape.

When the tape is installed in the tape recording / reproducing apparatus of the present invention, the rotary head 22 reads the total tape winding amount information on the tape and sends it to the recording / reproducing device 26. The recording / reproducing device 26 sends the total tape winding amount information to the discriminator 18.

The operation of the other constituent elements is the same as that of the first and second embodiments, and will be omitted.

As described above, by recording the total tape winding amount information on the tape, by reading the recorded total tape winding amount information when the tape is reused, it is possible to accurately and at the beginning or end of the tape. It is possible to detect the total winding amount of the tape without sending the tape to a stable tape running.

Further, when the total tape winding amount information is recorded on the tape, if the total tape winding amount information is recorded based on the command for unloading the tape as in the present invention, the tape can be reused when the tape is reused. The total winding amount information can be obtained in a short time. Further, if the total tape winding amount information is recorded after a predetermined time has elapsed after the recording operation is completed, it is possible to improve the operability without restarting the tape or the drum.

[0072]

As described above, according to the present invention, the initial object can be achieved. That is, even when an intermediate winding tape is used, the total tape winding amount can be detected accurately and in a short time, and stable tape running can be performed.
Therefore, the tape life and the reliability of the device can be improved.

[Brief description of drawings]

FIG. 1 is an operation explanatory diagram of the present invention.

FIG. 2 is an operation explanatory diagram of the present invention.

FIG. 3 is an operation explanatory diagram of the present invention.

FIG. 4 shows an example of the effect of the present invention.

FIG. 5 is an explanatory view of the principle of the present invention.

FIG. 6 is an explanatory view of the principle of the present invention.

FIG. 7 is an explanatory view of the principle of the present invention.

FIG. 8 is an explanatory view of the principle of the present invention.

[Explanation of symbols]

1 ... tape 2 ... Take-up reel 3 ... Delivery reel 8 ... Tape leading edge detector 12 ... Total tape winding amount calculator 1 13 ... Winding reel winding diameter calculator 14 ... Winding reel temporary winding diameter value storage memory 17 ... Tape total winding amount calculator 2 23 ... Track crossing detector 24 ... Crossing track number detector

Continuation of the front page (72) Inventor Shigemitsu Higuchi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Multimedia system development headquarters (56) Reference JP-A-5-74115 (JP, A) Kaihei 6-333302 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 15/46

Claims (5)

(57) [Claims] 1. A recording / reproducing apparatus for recording information on a magnetic tape or reproducing information from the magnetic tape, comprising means for driving the tape, and winding for detecting rotation number information indicating the number of times the winding reel has rotated. Take-up reel rotation speed detection means, feed-out reel rotation speed detection means for detecting rotation speed information that is the number of times the delivery reel has rotated, and take-up reel rotation cycle detection for detecting information proportional to the rotation cycle of the take-up reel. Means, a delivery reel rotation cycle detection means for detecting information proportional to a rotation cycle of the delivery reel, an output result of the winding reel rotation cycle detection means, an output result of the delivery reel rotation cycle detection means, and an output result of the take-up reel speed detecting means, the feed on the basis of the output result of reel rotation speed detecting means, before First tape total winding amount detecting means for detecting information corresponding to the sum of the axially projected areas of the tape wound on the take-up reel and the delivery reel and the reel hub, and the first total tape winding amount detecting means a output and the output of the take-up reel rotation period detecting means, the first tape speed control means for controlling the tape speed based on the output results of the reel rotation period detecting means feeding the said first The total tape winding amount detection means of the
In the ratio of the rotation cycle of the delivery reel and the take-up reel
It has a rotation period ratio detecting means for detecting corresponding information,
Run the tape from any time, and
Output result of the delivery reel rotation speed detection means during a fixed period
And the take-up reel rotation for a predetermined period from the start of running
The output result of the number detection means and the output of the rotation period ratio detection means.
A magnetic tape recording / reproducing apparatus characterized by detecting the total winding amount of the tape based on the force result . 2. The first total tape winding amount detecting means includes r (t): a winding radius of a take-up reel at an arbitrary time point, and N (0): a take-up reel and a take-up reel at the arbitrary time point. Rotation period ratio, Td: Tape thickness, n (s): Number of rotations of the delivery reel obtained by running the tape for a predetermined period from the arbitrary time point, n (t): Running the tape for a predetermined period from the arbitrary time point When the number of rotations of the take-up reel obtained by S is the total winding amount of the tape, And [Equation 5] The magnetic tape recording / reproducing apparatus according to claim 1, wherein the total tape winding amount is detected by using the. 3. The first tape speed control means, the output result of the take-up reel rotation cycle detection means, the output result of the delivery reel rotation cycle detection means, and the first total tape winding amount detection means. A first winding diameter detecting means for detecting the winding diameter of the winding reel, which is the winding radius of the tape wound on the winding reel, based on The output of the means,
2. The tape speed is controlled based on the output result of the take-up reel rotation cycle detecting means.
Or the magnetic tape recording / reproducing apparatus according to 2. 4. A magnetic head mounted on a rotating drum,
A recording / reproducing apparatus for recording or reproducing information obliquely to the longitudinal direction of a magnetic tape, comprising means for driving the tape, and winding reel rotation cycle detection for detecting information proportional to the rotation cycle of the winding reel. Means, a delivery reel rotation cycle detection means for detecting information proportional to the rotation cycle of the delivery reel, a means for setting winding diameter information of the take-up reel to a predetermined value, and a tape for stabilizing the tape based on the predetermined value. First tape running control means for running, a rotary head for playing back information recorded on a tape, control means for driving the rotary head at a predetermined rotation speed, a playback signal output from the rotary head, and Third winding diameter detecting means for detecting the actual winding diameter of the take-up reel based on a set value, and tape based on the third winding diameter detecting means A third tape total winding amount detecting means for detecting a winding amount, and a third tape speed controlling means for controlling a tape speed based on an output result of the third tape total winding amount detecting means, The third winding diameter detecting means detects the crossing of the data track recorded on the tape by the rotary head, and the rotary head detects the data track based on the output result of the crossing detecting means. And a means for counting the number of times the magnetic tape has been traversed, the magnetic tape recording / reproducing apparatus being characterized in that the winding diameter of the winding reel is detected based on the counting means and the set value. 5. The third tape speed control means, the output result of the take-up reel rotation cycle detection means, the output result of the delivery reel rotation cycle detection means, and the third tape total winding amount detection means. And a fourth winding diameter detecting means for detecting the winding diameter of the winding reel based on the output result of the fourth winding reel winding diameter detecting means,
5. The tape speed is controlled based on the output result of the take-up reel rotation cycle detecting means.
A magnetic tape recording / reproducing apparatus as described in.