JPS63153758A - Reel controller - Google Patents

Abstract

PURPOSE:To reduce a take-up time by comparing a higher voltage in generated voltage in response to the driving of both reel based with a reference voltage, and applying feedback control to the reel motor so as to decreased the speed deviation with simple constitution in a reproducing device using a rotary head. CONSTITUTION:FG pulse frequencies Fa, Fb in response to the base drive of the reels 1, 2 are converted into voltages Va, Vb by frequency-voltage converters 3, 4, a higher voltage selected by a comparator section 5 and outputted as the voltage Vc. The voltage Vc is fed to a differential amplifier 6 set with a reference voltage in response to a desired speed, an error voltage is formed and the reel motor of the reel 1 or 2 is subject to feedback control corresponding to the switch 8. Thus, the tape speed with a constant relative speed with the rotary head speed is subject to speed deviation with simple constitution within a limited range possible for reproduction to bring its speed, the winding time is reduced and stable high speed reproduction is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a reel control device in a tape playback device using a rotary head.

B0 Summary of the Invention A device that performs reel control includes two FV conversion circuits that convert two types of FG pulses generated by the rotation of two reels into voltages, and a device that converts the higher of the two types of voltage obtained by the FV conversion circuits. A device comprising a selection circuit that selects a potential, a circuit that compares and amplifies the selected voltage and a reference voltage, and a drive unit that feeds back the compared and amplified signal to the reel motor.

C0 Conventional Technology In a tape playback device using a rotating head, the relative speed between the tape and the rotating head must be kept constant in order to read data recorded on the tape. There is a method of running the tape at high speed and adjusting the speed of the rotary head so that the relative speed between the tape and the rotary head remains constant. To read data quickly, it is best to keep the relative speed of the tape and the rotating head constant and increase the speed of both. However, even if the relative speed of the tape and the rotating head is constant, if the speed exceeds a certain , it becomes impossible to read the data reliably.

Therefore, it is necessary to control the tape so that it runs as fast as possible within a predetermined speed. Furthermore, the smaller the tape speed deviation, the smaller the speed deviation of the rotary head, so it is desirable to reduce the speed deviation.

One of the conventional methods is to rotate one reel motor at a constant rate, but with this method the average speed of the tape is low and it takes a lot of time to wind the tape.

The disadvantage was that the speed deviation was also large.

D1 Problems to be Solved by the Invention The purpose of the present invention is to reduce the above-mentioned conventional drawbacks as much as possible, reduce speed deviation within a specified speed, and shorten the time required for winding. The device configuration is simple and therefore inexpensive.

It is an object of the present invention to provide a reliable reel control device.

Means for Solving the E0 Problem In order to achieve the above object, the reel control device according to the present invention includes two voltage generating means each generating voltages corresponding to the rotation of the two reel bases, and one of the above two voltages. A selection circuit that selects a higher potential, a comparison and amplification means that compares and amplifies the voltage selected by the selection circuit and a reference voltage, and a reel that feeds back the signal comparatively amplified by the comparison and amplification means to the reel motor. The gist is to include a drive section.

F6 Effect In the reel control device according to the present invention, the reel referred to when controlling the reel rotational speed is replaced from the time when the reel is empty until the end of winding. That is, the reel on which more than half of the tape is wound is controlled to have a constant rotational speed. In this way, speed deviations are kept small within a defined speed.

G. EXAMPLES The present invention will be explained in more detail using examples below with reference to one drawing, but these are merely illustrative and various modifications and improvements can be made without going beyond the scope of the present invention. Of course it is possible.

FIG. 1 is a block diagram showing the configuration of a reel control device according to the present invention, in which 1 indicates reel A, 2 reel-JL/B, 3
is FV converter A, 4 is FV converter B, 5 is comparison section, 6 is differential amplifier section, 7 is drive section, 8 is switch, Fa
, Fb is the FG pulse frequency, Va and Vb are the FV converter output voltages, Vc is the comparator output voltage, and -Vr is the reference voltage.

FIG. 2 is a graph showing temporal changes in FG pulse frequency and tape speed in the apparatus shown in FIG.

The apparatus shown in FIG. 1 operates as follows.

First, move the tape wound on reel B 2 to reel A.
The case where 1 winds up will be explained.

The characteristics of the FV converter 3.4 used in this N are such that the higher the input frequency, the lower the output voltage, and can be configured with, for example, ICBA6302 manufactured by ROHM Co., Ltd. When reel 1゜2 is stopped,
Since the input frequency is zero, the output voltages Va and vb take their maximum values. The comparator 5 selects and outputs the higher voltage between Va and vb, and in this case outputs the maximum value. The comparator 5 is configured as shown in FIG. 3, and when Va≧vb, Vc=Va, and when Va<Vb, Vc=, Vb.

The Vc outputted here is inverted by the differential amplifier 6, then inverted once again by the drive unit 7, returns to the maximum value, and is supplied to the reel A 1 via the switch 8. When winding of the tape is started in this state, reel A 1 instantly starts rotating at high speed.

The output of FG built into each reel is F
supplied to the V converter A 3 and the FV converter B4;
This converter outputs voltages Va and vb corresponding to the rotational speeds of the respective reels. When the amount of tape wound on reel A 1 is less than the amount of tape wound on reel B 2 , the number of rotations of reel A 1 is greater than the number of rotations of reel B2. Reel rotation speed and F
At the G pulse frequency, Fa is higher than Fb,
At the outputs of converters 3 and 4, Va is lower than Vb.

Since the comparator 5 selects the higher voltage, in this case v
b is selected and output in the form of Vc=vb. The difference between vc and reference voltage Vr is amplified in the differential amplification section 6, inverted in the drive section 7, and then sent to the reel A1 via the switch 8.
be returned to. In the end, in this system, control is performed so that Vc and Vr become equal, so reel B 2
is kept at a constant rotation. The rotation speed at this time is determined by Vr. The left half of FIG. 2 is an area where the amount of tape wound on reel A 1 is smaller than the amount of tape wound on reel B 2 . Although the radius of reel B2 becomes smaller as time passes, the number of revolutions does not change.

Tape speed gradually decreases. On the other hand, the radius of reel A1 gradually increases and eventually becomes larger than the radius of reel B2. At this time, conversely, the rotational speed of reel B 2 becomes larger, and the frequency of the FG pulses of Fb becomes higher than that of Fa. Therefore, at the output of the converter,
Va is higher than vb, and the comparator 5 selects Va. As a result, control is performed so that the reel A 1 rotates at a constant rate. The situation at this time is shown in the right half of FIG. Reel A 1 over time
The radius of the tape increases, but the number of revolutions does not change, so the tape speed gradually decreases. Fig. 2 shows the results when the tape is started from the beginning, but even if the tape is started from the middle, the reel is still controlled to a constant rotation and stable results can be obtained.

Next, take the tape wound on reel A 1 and reel B.
In order for 2 to rewind, it is only necessary to switch switch 8, and the other operations are the same as in the above case. In other words, fast forwarding and rewinding of the tape can be accomplished by simply switching the switch 8.

As detailed in the H6 invention, according to the present invention, by simply changing the reference voltage, regardless of the position of the tape, and without exceeding a certain speed and therefore without damaging the tape,
It is possible to obtain an inexpensive and reliable reel control device that can wind up a tape more quickly than the conventional method, has a small speed deviation, and is inexpensive and reliable. This device can be used not only for tape playback devices using a single rotation head, but also for fast forwarding and rewinding of conventionally used cassette tape recorders, data recorders, etc.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a reel control device according to the present invention, FIG. 2 is a graph showing temporal changes in FG pulse frequency and tape speed in the device shown in FIG. 1, and FIG. 3 is a diagram showing the configuration of a comparison section. be. 1・・・・・・Reel A, 2・・・・・・・・・
・Reel B, 3-...FV converter A
, 4... FV converter B, 5...
...Comparison section, 6...Differential amplification section,
7....... Drive unit, 8...... Switch, Fa, Fb......FG Pulse frequency, Va, Vb... ... FV converter output voltage, Vc... Comparison section output voltage, Vr.
......Reference voltage. Patent Applicant Clarion Co., Ltd. Agent Patent Attorney Ei 1) Takesanbu f- This flower exchange g and j paralysis, Diagram 3 Procedural amendment letter November 2, 1986

Claims (1)

[Claims] (a) Two voltage generating means each generating voltages corresponding to the rotation of the two reel bases, (b) A selection circuit that selects the higher potential of the two voltages, (c ) Comparison and amplification means for comparing and amplifying the voltage selected by the selection circuit and a reference voltage; and (d) a reel drive section for feeding back the signal comparatively amplified by the comparison and amplification means to the reel motor. Reel control device.