JPH01277355A - Tape moving device - Google Patents

Abstract

PURPOSE:To obtain a tape tension control system superior in responsibility by controlling an S-reel motor with a bit of error information which is a mixture of a tension error and a speed error corresponding to a tape moving speed and a rotation period of a T-reel. CONSTITUTION:The tape speed V is calculated by detecting a rotation roller diameter R1 and a rotation roller period T1 with an S-motor speed reference generator 18. Moreover, a T-reel diameter Rt is calculated, while an S-reel diameter Rs is calculated, so that an S-motor speed reference Tsref is calculated by using the S-reel diameter Rs and the tape speed V. In a 3rd differential amplifier 19, a difference between the S-reel speed reference Tsref and an S-reel period Ts obtained an S-reel period detector 16 is amplified to be outputted as a bit of speed error information Es. On the other hand, a bit of tension error information Ef is outputted from a 2nd differential amplifier 11, and these bits of information Es and Ef are mixed by a mixer 20, and hence a bit of S-motor error information E is outputted to an S-motor driving circuit 13. By this method, the tape tension control system superior in responsibility can be constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a tape transport device having a tape tension control function.

2. Description of the Related Art Conventional tape transfer devices include, for example, the Japanese Patent Application Laid-Open No. 80-80
It is shown in Japanese Patent No. 283394. FIG. 5 shows a block diagram of a conventional tape transfer device.
This operation will be explained based on FIG.

1 is a take-up reel (hereinafter referred to as T reel), 2 is a
This is a supply reel (hereinafter referred to as an S reel), and the tape is transported in the direction of the arrow. A rotating roller 3 is brought into contact with the tape, and its rotation period is detected by a tape speed detector 4. A first differential amplifier 5 amplifies the difference between the tape speed reference value supplied from the terminal 6 and the output of the tape speed detector 4, and outputs speed error information. The T-reel motor drive circuit 7 applies torque to the T-reel drive motor (TM) 8 according to this speed error information.

The tape speed control system configured as described above operates so that the output of the tape speed detector 4 becomes equal to the tape speed reference value supplied from the terminal 6, and the tape transport speed is controlled to be constant.

9 is a fixed post 9a installed on the tape running path.

9b, a movable post 9c, and a spring connected to the movable post 9c.The tape tension is detected by detecting positional information of the movable post 9c with a tension detector 10. A second differential amplifier 11 amplifies the difference between the tension reference value supplied from the terminal 12 and the output signal of the tension detector 10, and outputs tension error information. The S reel motor drive circuit 13 applies torque corresponding to this tension error information to the S reel drive motor (SM) 14.

The tape tension control system configured as described above operates so that the output of the tension detector 10 becomes equal to the tensilon reference value supplied from the terminal 12, and the tape tension is controlled to be constant.

Problems to be Solved by the Invention In the tape buffer 9 shown in FIG. 5, the position of the movable boss 9c is determined by the balance between the tape tension and the force acting on the spring. Therefore, the tension reference values constituted by blocks 2.9 to 14 were designed in consideration of the resonance phenomenon that exists between the inertial force of the movable boss 9c and the spring. For this reason, it is difficult to configure a control system with good responsiveness, and in transient responses such as when the tape transport speed changes rapidly, the poor responsiveness may cause abnormal tension to be applied to the tape or the tape may become slack. It had some problems.

Furthermore, in recent years, tape tension control has become increasingly important as cassette tapes used in magnetic recording and reproducing devices have become thinner and thinner in order to increase their length.

As tapes become thinner, there is a need to control tapes with low tensile strength, and control is also used in which a torque is applied to a SUR motor in the same direction as the tape transport direction to feed the tape. In addition, VTRs for broadcasting and business use
Because high-quality performance is required, reel control involves wide tape width, large reel diameter, and extremely large reel inertia. Against this background, there is a strong desire to improve the responsiveness of tape tension control systems.

In view of the above, an object of the present invention is to provide a tape transport device having a tape tension control system with excellent responsiveness.

Means for Solving the Problems The present invention includes a cassette type detection means for detecting the type of tape cassette, a take-up reel detection means for detecting the rotation period of a take-up reel, and output information of the cassette type detection means and the winding. Calculating means for calculating a speed standard of the supply reel based on the output information of the pick-layer detecting means and the output information of the tape speed detecting means, and a speed for detecting the difference between the output information of the calculating means and the rotational speed of the supply reel. error detection means;
This tape transport device includes mixing means for mixing the output information of the speed error detection means and the output information of the tensilon error detection means.

Operation The present invention has the above-described configuration, so that in addition to the conventional tensilon error, the S reel motor can also reduce the tape transport speed and T I
Since the tape tension control system is controlled by the error information mixed with the speed error error corresponding to the rotation period of the J-ru, it is possible to configure a tape tension control system with excellent responsiveness.

Embodiment FIG. 1 shows a block diagram of a tape transport device in a first embodiment of the present invention. In Figure 1, 15
16 is a T reel period detector that detects the rotation period Tt of the T reel drive motor 8; 16 is a S IJ reel period detector that detects the rotation period TS of the S reel drive motor 14; 17 is a built-in tape that is being transferred. A cassette type detector 18 determines the type of cassette that has been loaded using a detection hole, etc., which is based on the cassette information C obtained by the cassette type detector 7, the period TI of the rotating roller, the diameter R1 of the rotating roller, and the T reel period Tt. SIJ-le motor speed reference value T
5ref, an S motor speed reference generator, 19 a third differential amplifier, 20 a mixer, and a second differential amplifier 11;
The output Ef and the output Es of the third differential amplifier 19 are mixed, and an error signal E is outputted to the S motor drive circuit 1B.

In FIG. 1, blocks that perform the same operations as in FIG. 5 are given the same numbers. Further, FIG. 2 is a flowchart showing the calculation processing contents of the S motor speed reference generator 18 in FIG. 1, and the present embodiment configured as above is explained based on FIG. The operation will be explained below.

The tape speed control system consisting of blocks 1, 3 to 8 has the same configuration as shown in FIG. The T-reel motor is controlled.

Here, Ts = S reel rotation period Tt = T reel rotation period d = Tape thickness L = Tape total length Rh = Reel hub radius ■ = Tape speed, Ts2 + Tt2 = 1/C12 --- (1) However, CI
is a constant determined by formula (2).

CI= (V/π)* (1/ (4dL/π+2Rh
2)) In equation (2), d, L, Rh are constants that are determined by knowing the type of cassette, and therefore (
If the cassette information, tape speed, and T reel cycle are known from equation 1), the S reel cycle corresponding to the tape speed can be found.

Tape tensilon is determined by the phase difference between the transport speed of the tape wound on the T reel and the transport speed of the tape pulled out from the S reel. In general, motor rotational speed control allows the frequency of motor rotational pulses generated as the motor rotates to be set to a high level, resulting in control with a higher cutoff frequency and better response than the tension control system described above. I am able to design a system. Therefore, in this embodiment, the conventional Tensilon error signal is mixed with the S'J-le rotational speed error signal as an error signal for driving the S reel motor that controls the tape Tensilon, and this mixed error signal is used. is used to control the S reel motor.

In FIG. 1, the tape speed V is the diameter R1 of the rotating roller 3.
By obtaining the rotation period TI from the tape speed detector 4, it can be calculated using equation (3).

■=π*R1/TI ---(3) Also, the rotation period Tt of the T reel is obtained from the T reel period detector 15, and the cassette information C is obtained from the cassette type detector 17, and sent to the S motor speed reference generator 18. Each is entered.

Cassette information C=V2/ (π”*c12) Based on the above principle, the S motor speed reference generator 18 uses the second
The calculation processing shown in the figure is performed.

In process 18a, the rotating roller diameter R1 is a known value.

The rotating roller period TI is detected, and the tape speed V is calculated as shown in equation (3). In process 18b, the T reel diameter Rt is calculated using the tape speed V and the T reel period Tt. Next, in process 18c, the above-mentioned cassette information C and T are
The S reel diameter Rs is calculated using the reel diameter Rt. Then, in process 18d, the S reel diameter R8 and tape speed V are used to calculate the S motor speed reference '['5ref.

The third differential amplifier 19 uses the thus calculated S reel speed reference 'p5ref and the S reel period detector 16
The difference in S reel period Ts obtained from the above is amplified and speed error information Es is output. On the other hand, tension error information Ef is output from the second differential amplifier 11, and these error information ES and Ef are mixed in the mixer 20, and S
Motor error information E is output to the S motor drive circuit 13.

As described above, according to this embodiment, the S reel motor is controlled by the tension error information and the S reel speed error information according to the tape transport speed, and it is possible to configure a tape tension control system with excellent responsiveness. can.

FIG. 3 is a block diagram of a tape transport device showing a second embodiment of the present invention. In FIG. 3, 21a is an amplifier with an amplification gain of Ka, 21b is an amplifier with an amplification gain of Kb (Ka<Kb), and 22 is a switch circuit that receives a transient signal indicating the transition of tape transport supplied from a terminal 23. (supplied by the system controller, etc.). In the figure, the difference from the configuration in FIG. 1 is that blocks 21 to 23 are provided, and when the tape transport is in a transient state, the switch circuit 22 is
The speed error information Es is switched to the ib side, and the speed error information Es is sent to the amplifier 2.
The information has passed through 1b. Conversely, when the tape transport is in a steady state, the information passed through the amplifier 21a is the speed error information E.
It is output to the mixer 20 as s.

Therefore, the configuration is such that the speed error information Es included in the S reel motor control error information E has a higher specific weight during a transient period, and the tension error information Ef has a higher specific weight during a steady state. Therefore, in the second embodiment, by providing a means that can vary the mixing ratio of tensileron error information and velocity error information, tension control with excellent responsiveness can be performed particularly during transitions in tape transport.

In addition, 1st. In the second embodiment, as means for detecting the tape speed, a configuration was shown in which the rotation period of the rotary roller in contact with the tape was detected, but a configuration using the control signal shown in FIG. 4 is also possible. VH8 system VTR
A control track is provided at one end of the tape, and a control signal of a constant frequency is recorded during recording. Therefore, by detecting the frequency of this reproduction control signal, the tape transport speed can be detected. For example, in a VH8 system VTR, a control signal is recorded at 30 Hz during recording, and if the playback control signal is 300 Hz, it can be seen that the tape transport speed is 10 times the tape speed during recording.

Therefore, as shown in FIG. 4, the control head 3a
The tape speed can also be detected by a configuration in which the signal reproduced by the control reproducing amplifier 3b is amplified and the amplified signal is supplied to the tape speed detector 4 via the waveform shaping circuit 3c.

In addition, microcomputers control input/output, timers,
It is widely used in electronic devices because it can easily perform various calculations. Therefore, the first. Each block shown in the second embodiment may be replaced by a microcomputer.

At this time, in the second embodiment, there is no need to stick to two mixing ratios of speed error information and tensicon error information, and a plurality of mixing ratios are possible. In addition to the processing procedure shown in the figure, for example, a table may be prepared and a target value may be searched from this table in response to various inputs in order to shorten the calculation time.

Effects of the Invention As explained above, according to the present invention, it is possible to configure a tape tension control system with excellent responsiveness, and in particular, tape damage does not occur even during transitions of tape transport, and its practical effects are is very large.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the tape transport device according to the first embodiment of the present invention, FIG. 2 is a flowchart showing the processing procedure for calculating the supply motor speed reference in FIG. 1, and FIG. A block diagram of a tape transport device in the second embodiment, FIG. 4 is a block diagram showing the configuration of tape speed detection means for detecting tape speed using a control signal, and FIG. 5 is a block diagram of a conventional tape transport device. It is a diagram. 1-... Take-up reel, 2... Supply reel,
8... Take-up reel motor, θΦ〇 tape buffer, 14... Supply reel motor, 1
7... Cassette type detector, 18... Supply reel motor speed reference generator. Figure 1 Figure 2 Illustration 3 Figure 4 Illustration 5

Claims (2)

[Claims] (1) Tape transfer equipped with a tape speed detection means for detecting the transfer speed of the tape transferred from the supply reel to the take-up reel, and a tension error detection means for detecting the tension of the tape and detecting the difference from the reference tension. The apparatus comprises: a cassette type detection means for detecting the type of the cassette in which the tape is installed; a take-up reel period detection means for detecting the period of the take-up reel; and information output from the cassette type detection means. arithmetic processing means for calculating a reference rotational speed of the supply reel based on information output from the take-up reel period detection means and information output from the tape speed detection means; output information of the arithmetic processing means and supply; It is characterized by comprising a speed error detection means for detecting a difference in the rotation period of the reel, and a mixing means for mixing information output from the speed error detection means and information output from the tension error detection means. tape transport device. (2) The tape transport device according to claim 1, wherein the mixing means is capable of varying the mixing ratio of the information output from the speed error detection means and the information output from the tension error detection means into a plurality of types.