JPH09138993A - Tape driving method and signal reproducer using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drive a tape at a prescribed speed even though the frictional force between the tape and a capstan is reduced. SOLUTION: The speed difference between the capstan and the tape is detected based on the velocity signal VS calculated in a calculating part 83 based on the velocity signal VC from a capstan servo part 71 and the frequency signal SF from a feeding reel motor part 12 to generate a signal WS. Moreover, when the speed difference exceeds a prescribed value, the signal SV based on the signals VC, VS is selected by a changer 86 based on the signal WS to be supplied to a driving signal generator 88. Then. the tape speed of a feeding side is controlled by driving the motor part 12 with the signal SD generated based on the signal SV and the tension signal SL from a detection part 46. When the speed difference is equal to or smaller than the prescribed value, a signal ST based on a tension setting signal SA and the tension signal SB from a tension signal generating part 66 is selected and then the tape tension of the feeding side is controlled by driving the motor part 12 with the signal SD generated based on the signal ST and the signal SL. Moreover, a winding side is similarly controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape driving method and a signal reproducing device using the same. Specifically, in a signal reproducing device that drives the tape by the frictional force between the tape and the capstan, when the speed difference between the tape and the capstan exceeds a predetermined value, the rotation torque of the reel is changed so that the speed difference disappears. When the tape speed is controlled and the tape is driven, and when the speed difference between the tape and the capstan does not exceed a predetermined value, the tape speed and the capstan speed are matched by controlling the tape tension and driving the tape. It prevents the tape from being subjected to abnormal tension.

[0002]

2. Description of the Related Art In a conventional signal reproducing apparatus such as a video tape recorder, not only reproduction in standard mode but also reproduction in slow mode in which the tape speed is slower than standard mode or several times faster than standard mode is performed. Playback can be performed in the double speed mode.

Here, when the video tape recorder is a drive system for driving a magnetic tape by using a pinch roller and a capstan, when the tape speed is low as in the standard mode, slow mode or double speed mode, The magnetic tape is pressed against the capstan by the pinch roller to drive the tape. At this time, the tape speed is determined by the capstan, and the tension of the magnetic tape is controlled by the reel. When the tape speed is several tens of times faster than the standard mode, such as the fast-forward mode and the rewind mode, the pinch roller moves away from the capstan and the reel controls the tape speed and tension.

In the video tape recorder of the driving system using the pinch roller and the capstan, the magnetic tape is driven by the pinch roller and the capstan or by the reel depending on whether the tape speed is low or high. Since it is switched, good accessibility cannot be obtained. Moreover, since the drive is switched, an excessive tension may be transiently applied to the magnetic tape during the switching.

Therefore, a video tape recorder has been proposed which can drive the magnetic tape by the frictional force between the magnetic tape and the capstan without using a pinch roller. In this video tape recorder, the tape speed is controlled by the capstan and the tension of the magnetic tape is controlled by the reel regardless of the operation mode. In the video tape recorder that drives the tape by the frictional force between the magnetic tape and the capstan, the drive is not switched regardless of whether the tape speed is low or high, so that good accessibility can be obtained. At the same time, it is possible to prevent transiently excessive tension from being applied to the magnetic tape.

[0006]

By the way, in a video tape recorder which drives a magnetic tape by the frictional force between the magnetic tape and the capstan, if the frictional force between the magnetic tape and the capstan decreases for some reason, slippage occurs and the magnetic force is reduced. The tape may not be driven at a predetermined speed.

Therefore, the present invention provides a tape driving method and a signal reproducing apparatus using the tape driving method which can drive the tape at a predetermined speed even if the frictional force between the tape and the capstan is reduced.

[0008]

In order to solve the above problems, a tape driving method according to the present invention is a friction driving method in which a tape wound on a reel is driven by a friction force with a capstan without using a pinch roller. In the tape drive device of the capstan drive system, when the speed difference between the tape and the capstan does not exceed the predetermined value, the tape tension is controlled to drive the tape, and the speed difference between the tape and the capstan is set to the predetermined value. When the value exceeds the value, the tape speed is controlled and the tape is driven until the speed difference reaches a predetermined value.

Further, in the signal reproducing apparatus according to the present invention, the tape wound with the both ends of the tape fixed between the supply reel and the take-up reel is driven by the frictional force between the tape and the capstan. A signal reproducing device for reproducing a signal recorded on a tape, comprising a capstan servo means for detecting the speed of a capstan and controlling the speed of the capstan, and a tape tension detecting means for detecting a tape tension between a supply reel and a capstan. No. 1 tension detecting means, second tension detecting means for detecting tape tension between the capstan and the take-up reel, first tape speed detecting means for detecting tape speed on the supply reel side, and take-up reel side Second to detect the tape speed of the
Based on the tape speed detection means, the capstan speed detected by the capstan servo means, the tape tension detected by the first tension detection means, and the tape speed detected by the first tape speed detection means. The supply reel servo means for controlling the supply reel, the speed of the capstan detected by the capstan servo means, the tape tension detected by the second tension detecting means, and the second tape speed detecting means are detected. And a take-up reel servo means for controlling the take-up reel based on the tape speed thus obtained. In the supply reel servo means and the take-up reel servo means, the speed difference between the tape and the capstan exceeds a predetermined value. If not, the tape tension is controlled to drive the tape, and when the speed difference exceeds a predetermined value, the tape speed is controlled to drive the tape. That.

According to the present invention, when the speed difference between the tape on the supply reel side and the capstan or the speed difference between the tape on the take-up side and the capstan exceeds a predetermined value, the supply reel servo means and the take-up reel servo means. The rotation torque of the reel is controlled by. When the speed difference is less than or equal to a predetermined value, the supply reel servo means and the take-up reel servo means control the tape tension between the supply reel and the capstan or between the take-up reel and the capstan.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a signal reproducing apparatus according to the present invention will be described below with reference to the drawings.
FIG. 1 shows the configuration when the signal reproducing apparatus according to the present invention is, for example, a video tape recorder.

In FIG. 1, a magnetic tape 10 is wound around a supply reel 11 and a take-up reel 15 which are arranged at predetermined intervals in a cassette with both ends of the tape fixed.
Further, the tape running path of the magnetic tape 10 is set by the guides 21 to 28, 31, 32 and the guide portions 29, 30. A tension regulator unit 4 is provided between the guides 22 and 23 and between the guide units 30 and 31 in order to keep the tension of the tape constant.
1, 51 are provided.

One end of the tension arms 42 and 52 of the tension regulators 41 and 51 is rotatably attached to rotary shafts 43 and 53 provided upright on a chassis (not shown). Also, tension arms 42, 5
A tension spring 44, one end of which is locked to the middle portion of 2,
The other end of 54 is locked so that the tension arm 42 is always urged counterclockwise and the tension arm 52 is always urged clockwise. At the other end of the tension arms 42 and 52, the tension post 4
5, 55 are provided. Then, the tension post 45 is brought into contact with the magnetic tape 10 between the guides 22 and 23 to apply an appropriate tension to the supply-side magnetic tape 10. Further, the tension post 55 is brought into contact with the magnetic tape 10 between the guide portion 30 and the guide 31 to apply an appropriate tension to the magnetic tape 10 on the winding side.

The magnetic tape 10 is provided between the guides 23 and 24.
A full width erasing head 61 is provided for erasing the signal recorded on the tape with the tape width, and a rotary head for recording and reproducing the signal on the inclined track of the magnetic tape 10 is arranged between the guides 25 and 26. An installed drum portion 62 is provided. A fixed head 63 is provided between the guide 28 and the guide portion 29 for recording a voice signal or a control signal on a longitudinal track of the magnetic tape 10. Further, a capstan 70 for driving the magnetic tape 10 is provided between the guide portions 29, 30.

On the other hand, a capstan speed setting signal for controlling the capstan 70 according to the operation mode is output from an operation control section (not shown) which controls switching of operation modes such as normal reproduction, fast forward and rewind. The CPC is supplied to the capstan servo section 71.

The capstan servo section 71 generates a capstan drive signal CPD based on a capstan speed setting signal CPC and a frequency signal CPF supplied from a capstan motor section 72, which will be described later, and supplies the capstan drive signal CPD to the capstan motor section 72. It

In the capstan motor section 72, the capstan 70 is driven based on the capstan drive signal CPD, and the capstan 70 is rotated at a predetermined speed. Further, a frequency signal CPF proportional to the rotation speed of the capstan 70 is generated and supplied to the capstan servo section 71.

The frequency signal CPF is frequency-voltage converted by the capstan servo section 71 and supplied to the supply reel servo section 81 and the take-up reel servo section 91 as the capstan speed signal VC.

Further, a position detector 46 for detecting the rotational position of the tension arm is attached to the tension arm 42 of the tension regulator unit 41, and a tension indicating the amount of tension of the magnetic tape 10 based on the rotational position of the tension arm. The signal SL is generated. The tension signal SL is supplied to the supply reel servo unit 81. Similarly, the tension signal TL is generated by the position detector 56 based on the rotational position of the tension arm 52,
It is supplied to the take-up reel servo unit 91.

The position detectors 46, 56 are constructed by using, for example, an MR sensor utilizing the so-called MR effect in which a change in magnetic field is used as a change in resistance value, and when the magnetic field is changed by the movement of the tension arm. The resistance value is changed based on the change of the magnetic field, and the tension signal is generated.

Further, the guide portions 29 and 30 are provided with tension detection sensors for detecting the tension of the magnetic tape 10 at the entrance and exit of the capstan 70,
The sensor signal SS is supplied from the guide unit 29 to the tension signal generating unit 66. Tension signal generator 6
In 6, the tension signal SB is generated based on the sensor signal SS and is supplied to the supply reel servo unit 81. Similarly, the sensor signal TS is supplied from the guide unit 30 to the tension signal generation unit 68, and the tension signal TB is generated by the tension signal generation unit 68 and supplied to the take-up reel servo unit 91.

The supply reel servo section 81 is supplied with a tension setting signal SA for controlling the tension of the magnetic tape 10 from an operation control section (not shown). The tension setting signal SA and the capstan servo section are supplied. 71
The supply reel motor drive signal SD is generated based on the capstan velocity signal VC from the position detector, the tension signal SL from the position detector 46, the tension signal SB from the tension signal generator 66, and the frequency signal SF from the supply reel motor unit 12 described later. It is generated and supplied to the supply reel motor unit 12.

In the supply reel motor unit 12, the rotational torque of the supply reel 11 is controlled based on the supply reel motor drive signal SD to supply the magnetic tape 10. Further, a frequency signal SF proportional to the rotation speed of the supply reel 11 is generated and supplied to the supply reel servo section 81.

Similarly, in the take-up reel servo section 91,
A tension setting signal TA for controlling the tension of the magnetic tape 10 is supplied from an operation control unit (not shown). The tension setting signal TA, the capstan speed signal VC from the capstan servo unit 71, and position detection. The take-up reel motor drive signal TD is generated based on the tension signal TL from the section 56, the tension signal TB from the tension signal generation section 68, and the frequency signal TF from the take-up reel motor section 16 described later, and the take-up reel motor section is generated. 16 are supplied.

In the take-up reel motor section 16, the rotation torque of the take-up reel 15 is controlled on the basis of the take-up reel motor drive signal TD to take up the magnetic tape 10. Further, a frequency signal TF proportional to the rotation speed of the take-up reel 15 is generated and supplied to the take-up reel servo unit 91.

Here, the capstan servo section 71 is shown in FIG.
The configurations of the supply reel servo unit 81 and the take-up reel servo unit 91 are shown.

First, in the capstan servo section 71, the capstan speed setting signal CPC from the operation control section (not shown) is supplied to the speed reference signal generator 75. The speed reference signal generator 75 generates the speed reference signal VR based on the capstan speed setting signal CPC.
The rotation direction of the capstan 70 is determined based on a capstan speed signal VC from a signal converter 77 described later, and the generation of the speed reference signal VR is controlled so that the capstan 70 is rotated in a desired direction. It Further, the rotation abnormality of the capstan 70 is detected based on the capstan speed signal VC, and the generation of the speed reference signal VR is controlled.

The speed reference signal VR generated by the speed reference signal generator 75 is supplied to the non-inverting input terminal 76 of the operational amplifier 76.
a. Further, the frequency signal CF supplied from the capstan motor unit 72 is frequency-converted by the signal converter 77.
The voltage is converted into a capstan velocity signal VC. The capstan speed signal VC is supplied to the inverting input terminal of the operational amplifier 76, the speed reference signal generator 75, the supply reel servo section 81 and the take-up reel servo section 91. In the operational amplifier 76, the capstan drive signal CPD is generated based on the speed reference signal VR and the capstan speed signal VC and is supplied to the capstan motor unit 72.

Next, in the supply reel servo section 81,
The tension setting signal SA supplied from the operation control unit (not shown) is the operational amplifier 82 of the supply reel servo unit 81.
Is supplied to the non-inverting input terminal of. Further, the tension signal SB is supplied from the tension signal generator 66 to the inverting input terminal of the operational amplifier 82, and the tension control signal ST is generated based on the tension setting signal SA and the tension signal SB to fix the signal switch 86. It is supplied to the terminal 86a.

Further, the frequency signal SF supplied from the supply reel motor unit 12 is supplied to the speed calculator 83.
The speed calculator 83 calculates the tape speed based on the frequency signal SF, and generates the speed signal VS based on the calculation result. For example, when the operation starts, the capstan 70 is rotated at a predetermined speed to drive the magnetic tape 10 to obtain a frequency signal SF proportional to the number of rotations of the supply reel. The radius of the magnetic tape wound around the supply reel 11 is calculated based on the speed of the capstan 70, and the operating radius of the magnetic tape 10 is calculated based on the calculated radius and the frequency signal SF supplied during the subsequent operation. The tape speed is calculated and the speed signal VS is generated. The radius of the wound magnetic tape is sequentially updated during operation.

The velocity signal VS thus generated
Is supplied to the non-inverting input terminal of the operational amplifier 84 and the speed difference detector 85. In addition, the capstan speed signal VC supplied from the capstan servo unit 71
Is supplied to the inverting input terminal of the operational amplifier 84 and is also supplied to the speed difference detector 85.

In the operational amplifier 84, the tension control signal SV is generated based on the speed signal VS and the capstan speed signal VC.
Is generated. The tension control signal SV is supplied to the fixed terminal 86b of the signal switch 86.

The speed difference detector 85 detects the speed difference between the speed signal VS and the capstan speed signal VC, and a switching control signal WS is generated based on the detection result and is supplied to the signal switch 86. .

In the signal switch 86, the movable terminal is controlled based on the switching control signal WS, and the tension control signal ST
Alternatively, any one of the tension control signals SV is selected, and the selected signal is supplied to the non-inverting input terminal of the drive signal generator 88 via the integrator 87.

The tension signal SL supplied from the position detector 46 is applied to the inverting input terminal of the drive signal generator 88.
Is supplied, and the supply reel motor drive signal SD is generated based on the selected tension control signal and the tension signal SL. This supply reel motor drive signal SD
Is supplied to the supply reel motor unit 12, and the supply reel 1
The rotational torque of 1 is controlled.

Next, the take-up reel servo section 91 is also constructed similarly to the supply reel servo section 81, and the tension setting signal TA supplied from the operation control section (not shown).
Is supplied to the non-inverting input terminal of the operational amplifier 92 of the take-up reel servo section 91. The tension signal TB is supplied from the tension signal generator 68 to the inverting input terminal of the operational amplifier 92, and the tension control signal TT is generated based on the tension setting signal TA and the tension signal TB to fix the signal switch 96. It is supplied to the terminal 96a.

Further, the frequency signal TF supplied from the take-up reel motor section 16 is supplied to the speed calculator 93. The speed calculator 93 calculates the tape speed based on the frequency signal TF, and generates the speed signal VT based on the calculation result.

Speed signal VT generated by speed calculator 93
Is supplied to the non-inverting input terminal of the operational amplifier 94 and the speed difference detector 95. In addition, the capstan speed signal VC supplied from the capstan servo unit 71
Is supplied to the inverting input terminal of the operational amplifier 94 and the speed difference detector 95.

In the operational amplifier 94, the tension control signal T is generated based on the speed signal VT and the capstan speed signal VC.
V is generated. The tension control signal TV is supplied to the fixed terminal 96b of the signal switch 96.

The speed difference detector 95 detects a speed difference between the speed signal VT and the capstan speed signal VC, and a switching control signal WT is generated based on the detection result and is supplied to the signal switch 96. .

In the signal switch 96, the movable terminal is controlled based on the switching control signal WT, and the tension control signal TT
Alternatively, any one of the tension control signals TV is selected, and the selected signal is supplied to the non-inverting input terminal of the drive signal generator 98 via the integrator 97.

The tension signal TL supplied from the position detector 56 is connected to the inverting input terminal of the drive signal generator 98.
And the take-up reel motor drive signal TD is generated based on the selected tension control signal and the tension signal TL. The take-up reel motor drive signal TD is supplied to the take-up reel motor unit 16 to control the rotation torque of the take-up reel 15.

Next, the operation will be described. For example, during playback or fast-forward operation, the capstan servo unit 7
1, the capstan motor section 72 is driven by the capstan drive signal CPD based on the capstan speed setting signal CPC from the operation control section (not shown), and the capstan 70 is rotated at a predetermined speed.

When the magnetic tape 10 is driven at a predetermined speed by friction with the capstan 70, the capstan 70 and the speed of the supply reel 11 calculated by the speed calculator 83 of the supply reel servo unit 81 match. Therefore, based on the switching control signal WS from the speed difference detector 85, the movable terminal of the signal switch 86 is set to the fixed terminal 86a side and the tension control signal ST is selected.

At this time, the drive signal generator 88 generates the supply reel motor drive signal SD based on the tension control signal ST and the tension signal SL from the position detector 46 and supplies it to the supply reel motor unit 12. For this reason,
The rotation torque of the supply reel 11 is controlled to control the magnetic tape 1.
The supply side tension of 0 is controlled.

Similarly, since the capstan 70 and the speed of the take-up reel 15 calculated by the speed calculator 93 of the take-up reel servo unit 91 match, the signal switch 96 selects the tension control signal TT. A take-up reel motor drive signal TD is generated based on the tension control signal TT and the tension signal TL from the position detector 56 and is supplied to the take-up reel motor unit 16. Therefore, the rotation torque of the take-up reel 15 is controlled, and the tension on the take-up side of the magnetic tape 10 is controlled.

In this way, the magnetic tape 10 on the supply side has a predetermined tension based on the tension setting signal SA, the tension signal SB from the tension signal generator 66, and the tension signal SL from the position detector 46.
The tension is controlled by a heavy servo system. Similarly, the magnetic tape 10 on the take-up side has a double servo system so as to have a predetermined tension based on the tension setting signal TA, the tension detection signal TT from the tension signal generator 68, and the tension signal TL from the position detector 56. Tension is controlled. Therefore, the magnetic tape 10 can be stably driven at a predetermined speed by the frictional force with the capstan 70.

Next, the frictional driving force is lowered due to dust adhesion on the surface of the capstan due to long-term use, material change on the surface of the capstan, or air entrapment between the capstan and the tape due to high speed rotation of the capstan. However, a case where the speed difference between the capstan and the tape becomes large will be described.

For example, during operation in the fast-forward mode, the frictional force between the magnetic tape 10 and the capstan 70 is reduced to cause slip, and the speed of the magnetic tape 10 becomes faster than the speed of the capstan 70, resulting in a large speed difference. Then, in the speed difference detector 85, the capstan speed signal VC and the speed calculator 8
The capstan 70 based on the speed signal VS calculated in 3
It is detected that the speed difference between the magnetic tape 10 and the magnetic tape 10 exceeds a predetermined value, for example, the tape speed in the standard mode. Similarly, the speed difference detector 95 detects that the speed difference between the capstan 70 and the magnetic tape 10 exceeds a predetermined value based on the capstan speed signal VC and the speed signal VT calculated by the speed calculator 93. . The speed difference detected by the speed difference detectors 85 and 95 is the accuracy of the tape speed calculated by the speed calculators 83 and 93 in the resolution of the frequency signals SF and TF and the radius of the magnetic tape 10 wound on the reel. Since errors occur due to factors such as the above, these are set in consideration of these errors, and are not limited to the tape speed in the standard mode.

In the signal switch 86, the tension control signal SV is generated based on the switching control signal WS from the speed difference detector 85.
Is supplied to the drive signal generator 88, and
The drive signal generator 88 generates the supply reel motor drive signal SD based on the tension control signal SV and the tension signal SL from the position detector 46. Based on the supply reel motor drive signal SD, the supply reel motor unit 12
Is driven to increase the rotational torque required to supply the magnetic tape 10. Similarly, the signal switch 96 selects the tension control signal TV based on the switching control signal WT from the speed difference detector 95 and supplies the tension control signal TV to the drive signal generator 98. The drive signal generator 98 also controls the tension control signal TV. The take-up reel motor drive signal TD is generated based on the signal TV and the tension signal TL from the position detector 56. The take-up reel motor drive signal TD drives the take-up reel motor section 16 to drive the magnetic tape 1.
The rotational torque required to wind up 0 is reduced. In this way, the tape speed of the magnetic tape 10 is slowed down by controlling the rotational torques of the supply reel 11 and the take-up reel 15.

After that, when the speed difference between the tape speed and the capstan speed becomes less than a predetermined value, the switching control signals WS, W
The tension control signals ST and TT are selected based on T, the tensions of the magnetic tapes 10 on the supply side and the winding side are controlled by the double servo system, and the magnetic tapes 10 are moved by the frictional force with the capstan 70. It is driven at a predetermined speed.

Even in the rewinding mode in which the tape running direction is opposite, when the frictional force decreases and the magnetic tape 10 and the capstan 70 have a predetermined speed difference, they are processed in the same manner, and the supply side, that is, the winding direction. By controlling the rotation torque of the take-up reel 15 and the rotation torque of the take-up side, that is, the supply reel 11, the tape speed is changed. When the speed difference becomes a predetermined value or less, the tension is controlled by the double servo system, and the magnetic tape 10 is driven at a predetermined speed by the frictional force with the capstan 70.

Further, when a predetermined speed difference is detected by the speed difference detectors 85 and 95, the movable terminal of the signal switch 86 is set to the fixed terminal 86b side, and the movable terminal of the signal switch 96 is set to the fixed terminal 96b side. If the speed difference exceeds a predetermined value for a predetermined period after the operation, the capstan 70 or the magnetic tape 10
Is stopped to protect the magnetic tape 10.

By the way, in the above-described embodiment, there is no portion between the capstan 70 and the take-up reel 15 which produces a frictional force unlike the drum portion 62. Therefore, the guide portion 30
It is assumed that only one of the tension signal TB based on the tension on the outlet side of the capstan 70 detected in step 1 or the tension signal TL from the position detector 56 is obtained, and the tension signal is used to control the tension. It may be done.

As described above, according to the above-described embodiment,
The magnetic tape 10 and the capstan 70 slip,
When the speed difference exceeds a predetermined value, the rotational torques of the supply reel motor unit 12 and the take-up reel motor unit 16 are controlled so that the speed of the capstan 70 and the speeds of the supply reel 11 and the take-up reel 15 are increased. Matched. Therefore, the accessibility is good and it is possible to prevent the magnetic tape 10 from being applied with excessive tension.

Further, in the above-described embodiment, the magnetic tape 1 is provided with the position detecting portions 46 and 56 and the guide portions 29 and 30.
Although the tension of 0 is detected and the tension is controlled using this detection signal, the supply reel motor unit 12 and the take-up reel are considered in consideration of the friction of the full-width erasing head 61, the drum unit 62, the fixed head 63, and the like. Even in the case of the program control method in which the frequency signals SF and TF from the motor section are arithmetically processed, and the tension of the magnetic tape 10 is controlled by controlling the rotational torque of the supply reel 11 and the take-up reel based on the obtained arithmetic result. Applicable.

Further, the signal reproducing device is not limited to the video tape recorder, but it is needless to say that the signal reproducing device can be applied to, for example, a digital compact cassette capable of reproducing an audio signal.

[0058]

According to the present invention, the capstan and the tape slip, and the speed difference between the tape on the supply reel side and the capstan or the speed difference between the tape on the winding side and the capstan exceeds a predetermined value. In some cases, the supply reel servo means and the take-up reel servo means can control the rotation torque of the reel to reduce the speed difference between the tape speed and the capstan speed on the supply reel side and the take-up side. When the speed difference is less than or equal to a predetermined value, the supply reel servo means and the take-up reel servo means control the tape tension between the supply reel and the capstan or between the take-up reel and the capstan. The friction force of the tape can drive the tape at a predetermined speed.

Further, since the tape speed or the tape tension is controlled according to the speed difference, it is possible to improve the accessibility and prevent the tape from being excessively tensioned.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a signal reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing a configuration of a servo unit.

[Explanation of symbols]

 11 Supply Reel 12 Supply Reel Motor Section 15 Take-up Reel 16 Take-up Reel Motor Section 41,51 Tension Regulator Section 46,56 Position Detection Section 66,68 Tension Signal Generation Section 70 Capstan 71 Capstan Servo Section 72 Capstan Motor Section 75 speed reference signal generator 77 signal converter 81 supply reel servo section 83, 93 speed calculator 85, 95 speed difference detector 86, 96 signal switcher 88, 98 drive signal generator 91 take-up reel servo section

Claims (5)

[Claims] 1. In a tape drive device of a friction capstan drive system in which a tape wound on a reel is driven by a frictional force with a capstan without using a pinch roller, a speed difference between the tape and the capstan is a predetermined value. When the speed difference between the tape and the capstan exceeds the specified value, the tape speed is controlled until the speed difference reaches the specified value. A tape driving method characterized by driving. 2. The tape driving method according to claim 1, wherein when the speed difference between the tape and the capstan exceeds a predetermined value, the rotation speed of the reel is controlled to control the tape speed. . 3. A signal for reproducing a signal recorded on the tape by driving a tape wound on the supply reel and the take-up reel with both ends of the tape fixed, by a frictional force between the tape and the capstan. In the reproducing apparatus, a capstan servo means for detecting the speed of the capstan to control the speed of the capstan, a first tension detecting means for detecting tape tension between the supply reel and the capstan, The second tension detecting means for detecting the tape tension between the capstan and the take-up reel, the first tape speed detecting means for detecting the tape speed on the supply reel side, and the tape speed on the take-up reel side are shown. Second tape speed detecting means for detecting, capstan speed detected by the capstan servo means, and first tension detecting means Based on the tape tension and the tape speed detected by the first tape speed detecting means, a supply reel servo means for controlling the supply reel, a capstan speed detected by the capstan servo means, and the first tape speed. 2 has a tape tension detected by the tension detecting means and a tape speed detected by the second tape speed detecting means, and a take-up reel servo means for controlling the take-up reel. The servo means and the take-up reel servo means drive the tape by controlling the tension of the tape when the speed difference between the tape and the capstan does not exceed a predetermined value, and when the speed difference exceeds the predetermined value, the tape speed is controlled. A signal reproducing device characterized in that it controls a tape to drive a tape. 4. When the speed difference between the tape and the capstan exceeds a predetermined value, the supply reel servo means and the take-up reel servo means control the rotational torque of the supply reel and the take-up reel to control the tape. The signal reproducing device according to claim 3, wherein the signal reproducing device controls the speed. 5. The first tension detecting means detects the tension of the tape on the supply reel side and the tension of the tape on the inlet side of the capstan, and the second tension detecting means detects the tension of the capstan. 4. The signal reproducing device according to claim 3, wherein the tension of the tape on the outlet side and the tension of the tape on the take-up reel side are detected.