JPS63112852A - Fast forwarding and rewinding device - Google Patents

Abstract

PURPOSE:To execute fast forwarding and rewinding at a high speed by providing the number of revolution detecting means of a winding side for detecting the number of resolution of a winding reel, the number of revolution means of a supply side for detecting the number of revolution of a supply reel, and a control unit for lowering separately a supply voltage to driving means of the supply side and the winding side. CONSTITUTION:At the time of rewinding, when it is detected by a number of revolution detecting means of a winding side that the number of revolution of a winding reel 28 has entered into a prescribed range, an applied voltage to a driving means of a supply reel 18 is lowered by one control unit 71. At the time of fast forwarding, when it is detected by a number of revolution detecting means of a supply side that the number of revolution of the supply reel 18 has entered into a prescribed range, an applied voltage to a driving device of the winding reel 28 is lowered by the other control unit 72. In such a way, a damage of a tape is prevented at the time of fast forwarding and rewinding, and also, fast forwarding and rewinding can be executed at a high speed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a fast forwarding and rewinding system for a video tape recorder, etc., which performs fast forwarding and rewinding faster than before, and which prevents stress from being applied to the end of the tape. Relating to a return device.

[Conventional technology]

FIG. 5 is a perspective view showing the structure of a conventional fast forward/rewind device for a video tape recorder. Referring to FIG. 5, the case of rewinding will be explained. In the figure, 28 is a take-up reel, and 18 is a supply reel. From the take-up reel 28, the magnetic tape 20 runs toward the supply reel 18 and is rewound.

Transparent leader tapes 19 are attached to both ends of this magnetic tape 20.
are connected, and the light emitting diode 15 and the 7th transaster 14 are faced to each other via this league tape 19.
Leader tape 19 that passes the light emitted from the light emitting diode 15
The leader tape 19 is detected by receiving light through the phototransistor 14. That is, the light emitting diode 15 and the seven-channel transistor 14 constitute a supply-side termination detector.

On the other hand, the take-up reel 28 is fitted into the take-up reel stand 21 and rotated counterclockwise by the take-up motor 23. A power source 52 is controlled by a start switch 42 and a second controller 32 and supplied to the motor 23 which is a driver of the take-up reel stand 21 .

Similarly, the supply reel 18 is fitted to the supply reel stand 11. This supply reel stand 11 is driven by a motor 13, and when winding, the motor 1
3 is not supplied with power.

In fast forwarding, the first controller 31, starting switch 41, and power supply 51 supply power to the motor 13 in the same configuration as in rewinding, and power supply to the motor 23 is stopped.

Further, 25 is a light emitting diode, which emits light through the leader tape 19 at the end of the fast-forward tape, d--)'
The arrangement is such that the light emitted from the phototransistor 25 reaches the phototransistor 24 and is energized.

7 The output of the autotransistor 24 is used to control the operation of the first controller 31, and the output of the phototransistor 14 is used to control the operation of the second controller 32. .

In such a conventional fast forward/rewind device, if the light emission is cut off by the magnetic tape 20 when the start switch 42 is closed, the second controller 32 is closed and the power source 52 is turned on to the motor 23. Electricity is applied, and the magnetic tape 20 is wound onto the take-up reel 28.

At the end of the magnetic tape 20, the light emitted from the light emitting diode 15 passes through the leader tape 19 and is received by the phototransistor 14. When the phototransistor 14 is energized, the second controller 32 is opened.

The motor 23 stops rotating, and rewinding is completed.

Fast forward! Since ll is performed symmetrically with rewinding on the motor 13 side, a description thereof will be omitted.

In such a conventional fast forwarding nine rewinding device, the magnetic team 70
It takes about 200 seconds to rewind 20. Therefore, by doubling the voltage of the power source 52, the rotational speed also increases, making it possible to rewind the film in, for example, 100 seconds.

[Problem that the invention seeks to solve]

However, even if the leader tape 19 energizes the phototransistor 14 and cuts off the second controller 32, the first take-up reel 28 rotates due to inertia and, for example, the leader tape 19
01: Im, what used to stop after rewinding will now stop after pulling out 80 scratches.

At this time, if the leader tape 19 is 501:Ill, problems arise such as cutting the tape.

This invention was made in order to solve these problems, and it is possible to prevent damage to the tape when rewinding a traveling body such as a magnetic tape, and to perform fast forwarding and rewinding at high speed. The purpose is to obtain equipment.

[Failure to solve the problem]

The fast forwarding and rewinding device according to the present invention includes: a rotation speed detection means on the winding side for detecting the rotation speed of one winding IJ + reel; a rotation speed detection means on the supply side for detecting the rotation speed of the supply reel; A control device is provided that individually lowers the voltage supplied to the drive means on the supply side and the winding side.

[For production]

In this invention, when the rotational speed detection means on the winding side detects that the rotational speed of the take-up reel falls within a predetermined range during rewinding, one control device controls the voltage applied to the drive means of the supply reel. When the rotation speed of the supply reel is detected to be within a predetermined range by the rotation speed detection means on the supply side during fast forwarding, the other controller controls the rotation speed of the take-up reel. Reduce the applied voltage.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a fast forward/rewind device of the present invention will be described based on the drawings. FIG. 1 is a perspective view showing the configuration of one embodiment. In FIG. 1, parts that are the same as those in FIG. 5 are given the same reference numerals, and parts that are different from FIG. 5 will be mainly described.

In FIG. 1, a reflector 17 is disposed on the outer peripheral surface of the supply reel stand 11, and a light emitting diode 12 and a phototransistor 16 are disposed opposite the reflector.

This reflector 17 is coated with black and white parts so that the light emitted from the light emitting diode 12 is reflected four times in one rotation.

The phototransistor 16 is sensitive to the reflection of the reflector 17, and operates as a supply-side rotation detector during rewinding.

Similarly, a reflector 27 is also placed on the outer peripheral surface of the supply reel stand 21.
is attached, and this reflector 27 also has a light emitting diode 22
It is coated separately in black and white so that the light emitted from it is reflected four times in one rotation.

A light emitting diode 22 and a phototransistor 26 are disposed opposite to the reflector 27. The phototransistor 26 receives the light reflected from the reflector 27 in response to the light emitted by the light emitting diode 22, and the phototransistor 26 receives the light reflected from the reflector 27 when the light is emitted from the light emitting diode 22. It operates as a rotation detector on the take side.

A second control device 72 detects information regarding the number of revolutions of the supply reel 18 from the output of the phototransistor 16, and when the number of revolutions of the supply reel 18 falls within a predetermined range, the power supply 62
, and the rotation of the motor 23 is reduced. This power source 62 is of a variable voltage type in place of the power source 52 in FIG. This second control device 72
A reference signal can also be added to the .

Similarly, the output of the phototransistor 26 is added to the first control device 71, and the reference signal is also input to the first control device 71.

The first control device 71 detects information regarding the number of rotations of the take-up reel 28 from the output of the phototransistor 26, and when the number of rotations of the take-up reel 280 falls within a predetermined range, it reduces the voltage of the power source 61 and controls the motor 13. It is designed to reduce the rotation of the engine.

The power source 61 is also of a variable voltage type in place of the power source 51 in FIG. 5. The other configurations are the same as in FIG. 4.

Hereinafter, the operation of the present invention will be explained using specific numerical values. That is, when the rotational speed of the supply reel becomes 20 rps or more based on the output of the supply side rotation detector, the rotational speed of the driver is decided to be reduced.

Now, there are 1000 pieces of 20mm thick tape on the supply reel 18.
It is wound up and the tape diameter is 6 steel. Take-up reel 28
Only league tape 19 is wound, and the tape diameter is 2.
It is aR.

When the switch 42 is closed in this state, the power source 62 is io
A voltage of v is supplied, and the motor 23 rotates at l Orps. After 90 seconds have passed, the winding side will roll the magnetic tape 20 times 900 times.
The tape diameter is 5.6 ctL, and the supply side tape diameter is 2.8 scratches.

At this time, the rotation speed of the supply reel 18 is 20 rps.
As described above, the frequency of the output of the phototransistor 16, which is input to the second controller 12, is 80 Hz or more.

This second controller 72 senses this and reduces the voltage of the power supply 62 to 5V, causing the motor 23 to rotate at 5 rps.

Thereafter, the take-up reel 28 winds the magnetic tape 20 100 times in 20 seconds, the league tape 19 is pulled out, the rotation of the motor 23 is stopped, and the winding is completed.

That is, the tape can be rewound in 110 seconds, the speed at the end of the tape is reduced by half, and the leader tape 19 can be stopped midway.

Conventionally, since the power supply 62 is assumed to be constant at 5V, the rewinding time is reduced to 200 seconds, and the winding time is halved.

In this first figure, is it the first system when fast forwarding? 1iil device 31
and the starting switch 4], the power supply 61, and the first control device 71 supply power to the motor 13 symmetrically to the case of winding υ. During rewinding, power supply is stopped. With such a configuration, the effects of the present invention can be obtained even during fast forwarding.

FIG. 2 is a circuit diagram of a specific embodiment of the second control device 72, and FIG. 3 is a waveform diagram of each part thereof.

In FIG. 2, a reference signal 100 (a 40 Hz square wave) is input to the T terminal of a frequency divider 171. The reset terminal R of the frequency divider 171 is grounded, and the output terminal Q is connected to the reset terminal R of the frequency divider 172.

The output 160 of the phototransistor 16 shown in FIG. 1 is input to the T terminal of the frequency divider 172. The output terminal Q of the frequency divider 172 is configured such that the discrimination output 600 is supplied to the power supply 62 via a diode 174, and the cathode of the diode 174 is connected to a resistor 176.
and a capacitor 175 in parallel circuit.

Next, the operation shown in FIG. 2 will be described with reference to the waveform diagram shown in FIG. 3. As shown in FIG. 3(a), the reference signal 100 is 40Hz.
is a square wave and is input to the T terminal of the frequency divider 171. The divider 171 divides the frequency by 8 and supplies the output terminal Q with a reset signal 173 shown in FIG. 3(b) to the reset terminal R of the frequency divider 172.

The frequency divider 172 is connected to the output 160 of the phototransistor 16 (
Figure 3 (C)) is divided by 16 and the signal 177 is sent to the output terminal Q.
(Fig. 3(d)) is generated.

Therefore, if the supply reel 18 rotates approximately 4 times during the period in which there is no reset signal 173, that is, the period in which 8 pulses of the reference signal 100 are divided, and there are 16 or more output pulses, the signal 177 is generated. I will do it.

Signal 177 is passed through diode 174 to capacitor 17.
5 is charged and the discrimination output 600 (third
Figure (e)) is obtained. The predetermined period here is a time constant determined by the values of the discharge resistor 176 and the capacitor 175.

In this way, the rotation speed of the supply reel 18 is 20 rps.
When the value exceeds the value, a determination output 600 is output.

FIG. 4 is a block diagram showing another embodiment of the second control device 72, in which the output 160 of the phototransistor 16 is input to the T terminal of a frequency divider 172 that divides the frequency by 16. The reset terminal R of this divider 172 is grounded, and the output terminal Q is connected to the divider 171.
is connected to the reset terminal R of.

The reference signal 100 is input to the T terminal 12 of the frequency divider 171, and the output 178 is output from the output terminal Q. That is, the connection positions of the frequency dividers 171 and 172 are reversed from the case of FIG. 2.

In the case of this FIG. 4, if the reference signal 100 can be divided by 8 by the frequency divider 171 in the section where the output 160 of the phototransistor 16 is divided by 16 by the dividing period 172, then the output terminal Q
Output 17 B ()'rus) appears. Therefore, when the rotational speed of the supply reel 18 is about 20 rps or less, no pulses are produced, and when the rotation speed is about 20 rps or more, no pulses are produced.

The invention described above is not limited to video tape recorders, but can be generally applied to winding up long objects quickly and safely.

〔Effect of the invention〕

As explained above, this invention reduces the voltage applied to the drive means of the take-up reel by one control device when the number of revolutions of the supply reel falls within a predetermined range during fast forwarding, and reduces the voltage applied to the drive means of the take-up reel during rewinding. When the number of rotations falls within a predetermined range, the voltage applied to the drive means of the supply reel is reduced by the other control device, which prevents damage to the tape during fast forwarding and rewinding, and also prevents damage to the tape during fast forwarding and rewinding. It has the effect of being able to rewind.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the fast-forwarding and rewinding device of the present invention, FIG. 2 is a block diagram showing the internal configuration of the first control device in the fast-forwarding and rewinding device, and FIG. FIG. 3 is a signal waveform diagram of each part of the control device shown in FIG. 2; FIG. 4 is a block diagram of another embodiment of the first control device, and FIG. 5 is a perspective view of a conventional fast-forwarding and rewinding device. 11... Supply reel stand, 14.16, 24.26...
・Phototransistor, 13.23...Motor, 12
．． 15,22.25...Light emitting diode, 17°27
...Reflector, 18... Supply reel, 19... Leader tape, 20... Magnetic tape, 21... Take-up reel stand, 31... First controller, 32... Second controller, 6d. 62... Power supply, 71... First control device, 72...
- Second control device. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] A rotation speed detection means on the supply side that detects the rotation speed of the supply reel during fast forwarding, a drive means for the take-up reel, a rotation speed detection means on the winding side that detects the rotation speed of the take-up reel during rewinding, a reel driving means; a supply end detection means for detecting a supply end of the running body between the supply reel and the take-up reel; a take-up end detection means for detecting a take-up end of the running body; a control device on the supply side that reduces the voltage applied to the drive means of the supply reel when the rotation speed detection means on the winding side detects that the rotation speed of the take-up reel falls within a predetermined range during rewinding; a control device on the take-up side that reduces the voltage applied to the drive means of the take-up reel when the rotation speed detection means on the supply side detects that the rotation speed of the supply reel falls within a predetermined range; a controller on the supply side that stops the drive means on the supply side when the end detection means on the winding side detects the end of the traveling body; and a controller on the winding side that stops the drive means on the supply side when the end detection means on the supply side detects the end of the traveling body during fast forwarding; and a controller on the winding side for stopping the driving means of the fast forwarding and rewinding device.