JPH03225659A - Reel drive controller - Google Patents

Abstract

PURPOSE:To travel a tape at high speed with high accuracy by calculating supply and take-up tape winding radius while traveling the tape at low speed, and controlling acceleration/deceleration for the rotation of both reels corresponding to the calculated tape winding radius. CONSTITUTION:At first, a take-up reel 4 is rotated at fixed low speed, tape tension is detected by a tension detection part 9 and a supply reel 1 is controlled so that the tension can be coincident with the reference value of tension. After a magnetic tape 7 is traveled only for a fixed distance at extremely low speed, the count values of pulse data from encoders 3 and 6 of the reels 1 and 4 are detected and further, by counting the pulses of a tape movement detection part 8, the traveling distance is detected. Next, the radiuses of the reels 1 and 4 are calculated by an arithmetic part 10 while using the traveling distance and the count value of the pulse data. Afterwards, corresponding to the calculated radiuses of the respective reels 1 and 4, reel angular velocity and reel angular velocity/tension correction gain is set. Then, corresponding to an operation command, acceleration is activated up to the high traveling speed.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an apparatus for conveying tape from reel to reel (
For example, it is related to a reel drive control device suitable for use in high-speed dubbing equipment), and can control acceleration and deceleration in a short time without putting an excessive burden on the tape, especially when using a large-diameter reel wrapped with a long tape. The present invention relates to a possible reel drive control device.

(Technical Background) Recorded music tapes and video tapes have recently become very popular, and in order to provide them in large quantities at low cost, high-speed dubbing devices have been actively developed. For example, a DAT (digital audio tape) high-speed dubbing device uses a tape speed that is 400 to 600 times the normal playback speed (the tape speed is approximately 5
Dubbing at a high speed of about 7+Il/s),
Improving productivity. In this case, the length of the tape is long and the reel of the high-speed dubbing device has a large diameter.
The radius of the reel around which the tape is wound varies widely.

Based on this background, the development of a reel drive control device for running magnetic tape at high speed using a large diameter reel has been awaited.

(Prior art) As a conventional reel drive control device, there is
There is a magnetic tape device described in No. 854.

As shown in FIG. 4, this includes a supply reel 31 wound with a magnetic tape 33, a magnetic head 34 for recording or reproducing digital information on the magnetic tape 33, and a magnetic head 34.
4, a take-up reel 22 for winding the magnetic tape 33 recorded or played back, two guides 35 provided on both sides of the magnetic head 34 to guide the positioning and running of the magnetic tape 33; Magnetic tape 3 wrapped around 32
a roller 36 that is pressed against the outermost periphery of the roller 3 and rotates by the rotation of the take-up reel 32; an arm 37 that holds the roller 36 at one end and rotates around the other end;
A spring 38 is attached to the roller 36 and applies a pressing force to the outermost circumference of the magnetic tape wound around the take-up reel 32, and a tension sensor 39 is used to detect the tension of the magnetic tape 33.

Further, an angle sensor 40 is provided at the rotation center of the arm 37 to output the rotation angle as a digital signal, and a digital signal corresponding to the rotation speed is output to the center of the winding rule 32. An encoder 41 is provided.

The running speed of the magnetic tape 33 is determined by an angle sensor 40.
and the output signal of encoder 41. That is, the take-up reel 32 is determined based on the output signal of the angle sensor 4o.
The diameter of the magnetic tape at the outermost circumference is determined, the rotational speed of the take-up reel 32 is determined from the output signal of the encoder 41, and from these values the diameter of the outermost circumference of the magnetic tape wound on the take-up reel 32 is determined. The speed, that is, the running speed of the magnetic tape 33 is calculated. This calculation is executed by a microprocessor or the like, and by comparing the running speed of the magnetic tape 33 with a predetermined value and controlling the drive motor of the take-up reel 32, the acceleration/deceleration time and running speed of the magnetic tape 33 are set to a predetermined value. The value is controlled.

(Problem to be solved by the invention) The conventional example described above had the following problems.

(a) An arm 37 or the like is required to determine the diameter of the outermost magnetic tape on the take-up reel 32. The angle sensor 40 is
The diameter of the magnetic tape at the outermost periphery cannot be determined accurately. Since the roller 36 at the tip of the arm 37 is in contact with the outermost periphery of the take-up reel, it becomes an unnecessary load.

(a) Since the drive motor of the take-up reel 32 is controlled by comparing the running speed of the magnetic tape 33 with a predetermined value, the drive motor of the take-up reel 32 is started in a short time;

That is, there is a large difference between the reel radius of the take-up reel 32 on which the magnetic tape is wound and the reel radius of the supply reel 31, and as shown in FIG. It is necessary to control the rotation of the supply reel 31. At this time, it is not possible to run the magnetic tape 33 at high speed without applying an excessive load to the magnetic tape 33 simply by letting the supply wheel 31 idle. In particular, when starting up, it is necessary to start up slowly, resulting in poor operability.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes a supply-side drive unit that rotationally drives a supply reel, a take-up side drive unit that rotationally drives a take-up reel, and a take-up side drive unit that rotationally drives a take-up reel. A supply-side detection unit that detects rotation, a take-up side detection unit that detects rotation of the take-up reel, and a tape movement amount detection mechanism that is disposed on a tape transport path between the supply reel and the take-up reel. At the time of initial startup, the tape is run at a low speed before the tape runs at a high speed, and based on the detection results from the supply side detection section, the winding side detection section, and the tape movement amount detection mechanism, the supply reel is detected. and a reel drive control device that calculates a tape winding radius on a take-up reel and controls the acceleration and deceleration of rotation of the supply reel and take-up reel according to the calculated tape winding radius. be.

(Function) In the reel drive control device described above, the tape winding radius of both reels on which the tape is wound is accurately determined using a simple configuration, and the tape winding radius of the take-up reel and the supply reel is adjusted according to the determined radius. Angular velocity, angular acceleration, and tension correction gain are variably controlled.

(Embodiment) An embodiment of the reel drive control device according to the present invention will be described in detail below with reference to the drawings. Fig. 1 is a configuration diagram of the reel drive control device, Fig. 2 is a flowchart showing the operation of the device,
FIG. 3 is a diagram showing characteristics at startup.

In FIG. 1, a supply reel 1 is driven by a supply motor 2, and 3 is a supply encoder that detects the rotation of the supply reel. The output of this supply side encoder 3 is counted by a pulse counter 11 at the next stage and then sent to a calculation unit 10.
has been entered.

The take-up wheel 4 is driven by a take-up motor 5.
Reference numeral 6 represents a take-up side encoder that detects the rotation of the take-up reel. The output of this winding-side encoder 6 is counted by a pulse counter 12 at the next stage and inputted to an arithmetic unit 10. A conveying path for the magnetic tape 7 is formed between the supply reel 1 and the take-up reel 4, and a tape movement amount detecting section 8 and a tension detecting section 9 are provided in this conveying path.

The tape movement amount detection section 8 includes a roller 8a that rotates as the magnetic tape 7 moves, and an encoder 8b that detects the rotation of the roller 8a, and a detection pulse is output from the encoder 8b. The detection pulses of the encoder 8b are counted by a pulse counter 13 at the next stage and inputted to the calculation section 10, where the tape movement amount and tape speed are detected.

The tension detection unit 9 consists of a tension arm 9a that rotates due to the tension of the magnetic tape 7 and a potentiometer 9b that detects the rotation angle of this tension arm 9a.
A voltage corresponding to the rotation angle is output from the tension meter 9b. The output voltage of the potentiometer 9b is the output voltage of the next stage A/
The signal is digitally converted by a D converter 14 and input to the calculation section 10. Note that 9c is a spring.

The calculation unit (for example, a microcomputer) 1° calculates the amount of movement (rotation speed) of the supply reel 2 by the supply side encoder 3 and the amount of movement (rotation speed) of the take-up reel 4 by the take-up side encoder 6, as will be described in detail later. rotation speed), the amount of movement of the magnetic tape 7 by the tape movement amount detection section 8, (the tension detection section 9
Depending on the detection results such as the tension of the magnetic tape 7),
The reel radius (reel radius is the tape winding radius up to the outermost circumference of the magnetic tape when the magnetic tape is wound) is determined, and the supply motor 2 and take-up motor 5 are controlled, and the magnetic To run a tape 7 at high speed and with high precision.

That is, the output of the calculation unit 10 is sent to the D/A converter 15.16.
After D/A conversion, the motor driver 17.18
It is output to the supply side motor 2 and the winding side motor 5 via.

Further, although not shown in the drawings, a transfer mechanism for, for example, DAT is provided in the transport path of the magnetic tape 7.

The reel drive control device configured as described above operates at high speed (for example,
The running operation is performed at a speed of about 5.times./s to 7.mu./s, which is 400 to 600 times faster than the normal playback speed.

At this time, at initial startup when the reel radius is unknown, such as when turning on the power or replacing the magnetic tape, the reel radius is determined before high-speed running, and the reel angular velocity and reel angular acceleration at startup are determined according to this reel radius. - Optimize the tension correction gain.

Next, the operation of the reel drive control device will be explained in detail. This operation is executed by the arithmetic unit 10 according to the flowchart shown in FIG.

Power is turned on, magnetic tape is replaced, etc. (Step 1)
01). Use the operation command (FF) from the operation panel.

REW, transcription) is input (step 102).

In order to accommodate any reel radius, the reel radius at initial startup is initially set as the middle between the maximum outer circumference and the minimum outer circumference. A tension correction gain G is set according to this initial value (step 103).

Tape movement amount detector 8 (pulse counter 13) winding/
The encoders 3 and 6 (their pulse counters 11 and 12) of the supply reel 4 are reset to start counting (step 104).

The take-up reel 4 is moved at a constant low speed (for example, 0.1 times the 10x speed).
2 m/s) (step 105), the tension detector 9 detects the tape tension T, and the supply reel 1 is controlled so as to match the tension reference value (step 10).
6).

A comparison is made to determine whether the magnetic tape 7 has traveled a certain distance at an extremely low speed (step 107). When the tilt tape 7 has traveled a certain distance, the count values P and P of the encoders 3 and 6 of the take-up/supply reel 1.4 are
Furthermore, the running distance t s is detected by counting the pulses of the tape movement detecting section 8 (step 108).

Calculate using the running pressure fiL and the count values P and P.
Calculate the radii R and R of the take-up and supply reels.
s (step 109).

That is, let the reel rotation angle be θ, the number of pulses per revolution of the encoder of the reel motor be P, the number of 61 constant counts be P, and the reel radius be R, and the reel radius is calculated from the above relationship.

At this startup, the magnetic tape 7 is run at an extremely low speed, so even if there is a difference between the reel radius initially set in the device and the actual reel radius, the magnetic tape 7 runs relatively stably.

Then, the reel angular velocity, reel angular acceleration, and tension correction gain are set according to the radius of each reel calculated as described above (step 11o). The vehicle is accelerated to a high speed according to the operation command (step 111).

That is, when the reel radius R is small, the reel angular velocity, reel angular acceleration, and tension correction gain are increased, and when the radius R is large, the reel angular velocity, reel angular acceleration, and tension correction gain are decreased. Therefore, even if a large-diameter reel is used to start up the magnetic tape at high speed, the reel angular velocity, reel angular acceleration, and tension correction gain of the take-up and supply reels are set in accordance with the reel radius. It can be started up in a short time without any burden.

Even during high-speed driving, similar to steps 108 and 109,
Using the mileage and count values P and P,
s and calculates the radii R and R8 of the take-up and supply reels, and controls the rotation of the take-up and supply reels 1 and 4 (step 112).

When a stop operation command is input manually, the reel angular velocity, reel angular acceleration, and tension correction gain are set according to the reel radius at that time, and a deceleration and stop operation is executed (step 113).
). At this time, the small radius of the road just before the stop is memorized (step 114).

When the operation command for high-speed running is input again (step 115), the reel angular velocity, reel angular acceleration, and tension correction gain are set based on the memorized reel radius, and a startup acceleration operation is executed (step 116). ).

As described above, according to the present reel drive device, even when a large diameter reel is used to run a magnetic tape at high speed, the reel angular velocity of the take-up/supply reel can be adjusted according to the reel radius.
The reel angular acceleration/tension correction cane is set so that the magnetic tape is started and runs at high speed while keeping the tape speed and tension stable at all times. In the reel drive device of the present invention,
With a standard drive device configuration, before running the tape at high speed, the tape is run at an extremely low speed to accurately detect the winding radius of both tapes, and then the reel angular velocity and reel angle corresponding to this tape winding radius are determined. Tape speed and tension are controlled by determining the acceleration/tension correction gain, so even when using a large diameter reel wrapped with long tape, it can be started up in a short time without putting excessive stress on the tape, and furthermore, the tape can be It can run at high speed and with high precision.

Furthermore, there is no need to add an arm or roller to detect the radius of the reel as in the past, so there is no increase in cost.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of the reel drive control device according to the present invention, Fig. 2 is a flowchart showing the operation of the device, Fig. 3 is a diagram showing characteristics at startup, and Fig. 4 is a diagram showing a conventional example. The configuration diagram shown in FIG. 5 is a diagram showing characteristics at startup of a conventional example. 1... Supply reel, 2... Supply side motor, 3...
Supply side encoder, 4... Take-up reel, 5... Take-up side motor, 6... Take-up side encoder, 7... Magnetic tape, 8... Tape movement amount detection unit, 9...・Tension detection section, 10... Arithmetic section (microcomputer), 17.1
8...Motor driver.

Claims (1)

[Claims] A supply side drive section that rotationally drives a supply reel, a take-up side drive section that rotationally drives a take-up reel, a supply side detection section that detects rotation of the supply reel, and a winding side drive section that detects rotation of the take-up reel. It consists of a pick-up side detection unit and a tape movement amount detection mechanism disposed on the tape transport path between the supply reel and the take-up reel. Then, the tape winding radius on the supply reel and take-up reel is calculated from the detection results from the supply side detection unit, the winding side detection unit, and the tape movement amount detection mechanism, and the calculated tape winding radius is calculated. A reel drive control device characterized in that the rotation of the supply reel and take-up reel is controlled to accelerate or decelerate depending on the radius.