JPH0358339A - Reel driver - Google Patents

Abstract

PURPOSE:To prevent the permanent distortion, flaw, and damage of a magnetic tape and coming off a reel hub occurring by detecting a tape quantity wound on a reel and the rotating quantity of the reel, and controlling feed speed corresponding to the tape quantity. CONSTITUTION:A control signal on the magnetic tape 3 is detected by bringing the tape 3 into contact with a control signal head 10. The head 10 further detects the rotating quantities of a supply reel 18 and a take-up reel 19, and detects the tape quantities wound on both reels 18 and 19. The tape is fed at fast speed when sufficient tape quantity remains, and it is fed at low speed when the tape quantity is insufficient. Also, rotating speed to drive the reel is controlled so as to keep the feed speed of the tape constant by applying servo setting the control signal as reference. Thereby, the feed at very high speed of the tape can be realized extending over the entire area from the start point to the end point of the tape without applying an excessive load on the tension of the tape.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reel drive device that can run a tape at high speed during winding and fast forward mode of a magnetic tape device such as a VTR (video tape recorder). It is related to.

[Conventional technology]

Tape running using the parallel loading method that is widely used in equipment? This is a system diagram showing the tape running path at the time (unloading state).
In the rotating drum with a video heel la, lb is fixed at a position exactly 180' with respect to the center of the rotating drum l and slightly protrudes to the periphery of the drum.

2a, 2b, 2c are loading tape guides on the supply side (supply side), and 2a1, 2b+, 2c are loading tape guides on the take-up side (take-up side), both of which stably load the magnetic tape 3 on the rotating drum 1. Among them, tape guide 2b. 2c, 2b+.
In the case of 2ct, the magnetic tape 3, which is in a state of movement from the dotted line position to the position shown by the solid line in FIG. 4, is pulled out from the cassette 14 and mounted on the rotating drum 1.

4a is a guide roller on the supply side, and 4b is a guide roller on the take-up side, which are impedance rollers for reducing small vibrations of the tape 3 and reducing wobble.

5 is a full-width erasing head; 6.7 is a tape guide; tape guide 7 can be moved between two types of stop positions shown by dotted lines and solid lines; The magnetic tape 13 is moved to the position shown by the solid line in FIG.

8 is a tape tension regulator, 9 is an audio erasing head, and 10 is an audio signal/control signal head, and these heads 9 and 10 are integrated to provide mechanical precision.

Tape guide 11, pinch roller 12, capstan l
3, during recording and reproducing as shown in FIG. It appears to move to a certain position and then stop.

Tape guides 15 to 17 are provided in a cassette 14 in which the magnetic tape 3 is stored. These tape guides 15 to 17 are tape guides for smoothly supplying or winding up the stored magnetic tape 3. Also,
Also provided within the cassette 14 are a supply reel 18 and a take-up reel 19.

In the VTR device configured as described above, during recording and reproducing operations, the magnetic tape 3 is moved by the movable tape guide mechanism 2b,
2c, 2b+, 2c+. 7, and as shown in FIG. 4, it contacts the video heads la, lb, the full-width erase head 5, the audio erase head 9, and the audio signal and control signal head 10, and each head performs its own operation.

Also, during rewinding and fast forwarding operations, the tape guides 2b and 2c on the supply side, the tape guide 2b on the winding side. 2C+ and the tape guide 7 are housed in the cassette 14, the magnetic tape 3 is placed in the (a). As shown in 51F, in the unloading state, -m is made to run at a speed 20 to 30 times faster than in the recording/reproducing mode.

During this rewinding and fast-forwarding operation, the outer diameters of the supply reel 18 and take-up reel 19 inside the cassette tape are large, and the outer diameter of the take-up reel 19 is small), and the fast-forwarding operation is performed as shown in FIG. As shown in the diagram of the relationship between tape position and tape speed in (b), the speed is slow at first (the take-up reel is small) and gradually becomes faster, and at the end of the tape the outer diameter of take-up reel l9 becomes larger. Yes, it becomes quite fast. Therefore, even at the end of the tape, the speed had to be kept at a speed (maximum 40 times) that would not cause permanent distortion or damage to the tape.

[Ll that the invention tries to solve! Title]

Since the conventional reel drive device is structured as described above, the tape is run at 20 to 30 times the speed during fast forwarding or rewinding. For example, commercially available VTR tape T
-120 (length of 245.4 m) from start to finish takes 4 to 6 minutes.

Furthermore, in order to rotate the supply reel 18 and take-up reel 19 faster, it is sufficient to increase the rotational force of the respective drive motors.
During fast forwarding), the tension applied to the tape increases, which may cause permanent distortion to the tape, peel the adhesive between the leader tape and magnetic tape, or destroy the fit between the leader tape and reel hub. There was a problem with putting it away.

The present invention was made to solve the above-mentioned problems, and it is an object of the present invention to provide a reel drive device that prevents permanent distortion, damage and destruction of a magnetic tape, and reel haptic detachment.

[Means to solve the problem]

The reel drive device according to the present invention includes a supply reel drive means for rotating a supply reel, a take-up reel drive means for rotating a take-up reel, a control {No. A position detection means for detecting the position of the running tape based on the rotation of the reel disk of the take-up reel and the supply reel and a control signal, and a control means for controlling the running speed of the running tape based on the output from the position detection means. It is characterized by being equipped.

[For production]

In this invention, for tape fast forwarding and rewinding operations, the magnetic tape is brought into contact with the control signal head to detect the control signal on the tape, and the amount of rotation of the supply reel and take-up reel is detected. The amount of magnetic tape wound on both reels is detected, and when there is a sufficient amount of tape, the tape is run at high speed, and when the amount of tape is small, it is run at low speed. Moreover, the rotational speed for driving the reel is controlled by a servo based on the control signal so that the tape running speed remains constant, whether at high speed or low speed. Ultra-high speed running is possible without applying excessive load to the tape tension over the entire area.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is an operation diagram of the reel drive device in a half-loading state, FIG. 2(a) is a block diagram showing the structure of the control system of the above device, FIG. 1 is a characteristic diagram of speed.Here, in FIGS. 1 and 2, the same parts as in FIGS. 4 and 5 are given the same reference numerals, explanations thereof are omitted, and different parts will be explained.

Figure 1. Figure 2 and Figure 4. As is clear from a comparison with FIG. 5, in this embodiment, the movable tape guide 2b+ is moved halfway in order to bring the tape 3 into contact with the control signal head 10 during fast forwarding and rewinding of the tape. different from. That is, when fast forwarding or rewinding the tape, the control signal head 10 on the tape is driven by the supply reel motor 20, and the rotation shaft of the supply reel motor 20 is A reflective temporary 21 is attached.

The reflection plate 21 is provided with a black and white contrast in order to detect the rotation of the supply reel motor 20, and this contrast is detected by the optical sensor 22 to detect the rotation of the supply reel motor 20.
The rotation speed is detected.

The optical sensor 22 consists of a light emitting diode and a light receiving diode, and the output of a weak electrical signal from the optical sensor 22 is amplified by an amplifier 23 and then sent to a microcomputer 32.
(hereinafter referred to as the microcontroller).

On the other hand, the take-up reel 19 is driven by a take-up reel motor 24. A reflective temporary 25 with a black and white contrast is also attached to the rotating shaft of the take-up reel motor 24.

The contrast of the reflective material 25 is detected by an optical sensor 26. Like the optical sensor 22, this optical sensor 26 is also horizontally composed of a light emitting diode and a light receiving diode.
The output of this optical sensor 26 is amplified by an amplifier 27 and sent to a microcomputer 32. Further, a magnetic tape is normally in contact with the control signal head 10 as in the recording/reproducing mode. Here, in Figure 2 (bl
Pink up the control signal recorded on the magnetic tape as shown in . Since this picked up control signal is a weak signal, it is amplified by a control signal amplifier 37 and its output is sent to the microcomputer 32.

The microcomputer 32 performs calculations based on the output pulse signals of each amplifier 23, 27, and 37, and sends the calculation results to the control circuit 33.
It is designed to be sent to The control circuit 33 outputs the result of this calculation to the motor drive amplifiers 34 and 35.

The motor drive amplifier 34 drives the supply reel motor 20, and the motor drive amplifier 35 drives the take-up reel motor 2.
It is designed to drive 4.

Next, the operation of this invention will be explained. First, in the case of tape fast forwarding and rewinding operations, the magnetic tape 3 comes into contact with the control signal head 10 during half loading as shown in FIGS. 1 and 2, unlike the conventional method shown in FIG.

Thereafter, take-up reel 19 and supply reel I8 rotate.

First, the operation in fast forward mode will be explained.

Here, the hub diameter r of the winding reel 19, the outer diameter Rt of the tape
, if the amount of winding in one rotation is 1t, then 1t = 2 π Rt
...+11 Here, the thickness of the magnetic tape 3 is d
, the length of the tape wound on the take-up reel l9 is Lt, then Lt -d=i (Rt2-r2) Therefore, Lt = ((-!-S-) 2- r
”} − (21d 2 π.

On the other hand, if the control signal interval is a, the take-up reel 1
Let n be the number of control signals that pass through the control signal head 10 during one rotation of winding head 9.
±1=n.

a Therefore, from the above formula (2), L t = a ( ('z÷)"-r") π = I (-)2- r "l
...(3) d 2 π.

Here, since d, π, a, and r are all constant, Lt can be found by finding n.

In other words, one rotation of the winding roll 19 is detected by the reflective roller 25 and the optical sensor 26 (if black and white contrast is applied as shown in FIG. 2, four pulses are generated in one rotation). How many control pulse signals are detected by the control signal head 10 during the generation period (n)?
By counting , the amount of tape on the winding roll 19 can be detected from equation (3) above.

That is, the position of the tape (which position in the total length of the magnetic tape) can be detected. The above +11, [2), (3j formula can be easily calculated by a small-scale microcomputer 32.

The output of the optical sensor 26 is amplified by an amplifier 27, and the amplified output pulse is sent to a microcomputer 32.

This microcomputer 32 calculates based on the output of this amplifier 27, and when Lt is small (at the head of the magnetic tape 3), a DC voltage is generated from the control circuit 33 so that the winding reel 19 rotates to the maximum. The amplifier 35 is driven at maximum power and the take-up reel motor 24 is rotated at maximum rotation speed. When the winding wheel 19 rotates at the maximum rotational speed and the magnetic tape 3 starts running at an extremely high speed (for example, running at 250 times as shown in FIG. 3), the control signal detected from the throat 10 is sent to the amplifier 35. , the reel motor 24 is controlled to run the tape at a constant tape speed of 250 times as shown in FIG. During this time, keep the tape position as above (3).
) continues calculation using the formula.

Next, when Lt becomes larger and comes to the end of the tape (n becomes larger), the control voltage of the control circuit 33 becomes the minimum, driving the amplifier 35 at the minimum power and rotating the take-up reel motor 24 at the minimum rotation speed. . After that, the servo is applied using the control signal to keep the tape speed constant.

As a result, the tape running speed is controlled as shown in FIG.

Next, the rewind mode will be described. At this time (J4
If the respective values of the 18 supply reels are is and Ls, then Ls = - [ ( )2 - r'' 1d 2π, which can be calculated and controlled in exactly the same way.

In the embodiment described above, the supply reel 18 and the take-up reel 19
Although a method has been described in which the rotation of the sensor is detected by the optical sensors 22 and 26, various other methods are possible, such as a magnetoresistive method and a gear method.

Further, instead of the microcomputer 32, another method may be used that counts the number of pulses and the frequency of the control signal generated during one revolution of the supply reel and take-up reel, but -1'ffi
It is possible to perform calculations without increasing costs by using a part of the microcontroller that controls the sequence of mechanical denoki.

As described above, according to the present invention, the tape can be fast-forwarded and rewound at high speed, and moreover, the tape can be run at a constant speed regardless of the position of the tape. Also, tapes recorded by changing the recording running speed from the middle of one tape (for example, VH
Even when fast forwarding and rewinding an S format tape (the first hour was recorded in standard mode and the remaining time in triple mode), constant tape speed control based on the control signal described above can be performed without any problem. Ru.

Further, in the present invention, a half-loading state is used, but a full-loading state may also be used, and there is no limitation as long as the control signal head 10 contacts the magnetic tape 3 and the control signal is detected.

Further, in the system of the present invention, in order to further increase the speed of the tape running at a constant speed, the rotational speed of both reels can be controlled by sending out and rotating another reel.

[Effects of the Invention] As explained above, according to the present invention, the control signal recorded on the magnetic tape is subjected to pisokassobu during tape fast forwarding and rewinding operations, and the frequency of the detected control signal is related to the tape position. The rotational speed of the supply reel and take-up reel is controlled so that the rotational speed of the supply reel and take-up reel is constant, and the remaining amount of tape is measured. This allows the tape speed and tape tension to be constant over the entire tape during high-speed forwarding and rewinding, causing excessive load to be applied to a part of the tape and causing the tape to run at a constant speed. This prevents permanent distortion, damage and destruction, and enables high-speed fast forwarding and rewinding without damaging the contact portion of the reel hub. Furthermore, since the tape speed is constant, there is also the advantage that the running sound during fast forwarding and rewinding is constant.

[Brief explanation of drawings]

FIG. 1 is an operational diagram of the reel drive device according to the present invention in a half-loading state, and FIG. 2 fa+ is an ilN of the above device.
] Figure 2+b) is a Bronnock diagram of the wholesale system, Figure 2 is a diagram of the recording format on the tape, Figure 3 is a characteristic diagram of the tape position and tape speed during high-speed running, Figure 4 is the plane of the conventional device during unloading. FIG. 5(b) is a diagram showing the relationship between the tape position and the tape speed during fast forwarding. ■...Rotating drum, LA, LB...Video head,
2a, 2az6, 11.15.16. x'7--Fixed tape guide, 2b. 2bz, 2c, 2c+, 7...
Movable tape guide, 3... Magnetic tape, 4... Guide roller, 5... Full width erasing head, 8... Tape tension regulator, 9... Audio erasing head, 10
...Audio signal, control signal head, 12...
Pinch roller, 13...capsun, 14...cassette, 18...supply reel, l9...take-up reel. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] a supply reel drive means for rotating a supply reel; a take-up reel drive means for rotating a take-up reel; a control signal head for detecting a control signal on the tape;
a position detection means for detecting the position of the running tape based on the rotation of the reel disks of the take-up reel and the supply reel and control signals; and a control means for controlling the running speed of the running tape based on the output from the position detection means. A reel drive device characterized by: