JPH01176351A - Tape tension control device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording/reproducing device, and more particularly to a tape tension control device for stabilizing tape tension in a tape running system.

Conventional technology - In a device that extracts magnetic tape from a supply reel wound with magnetic tape and records/reproduces signals on an FG,
It is necessary to maintain the tension of the drawn tape at an appropriate value.

Conventionally, in order to achieve the above purpose, a means for detecting the tension of the magnetic tape that has been pulled out is provided, and according to the detection result, the driving torque of the supply reel on which the magnetic tape is wound is controlled to keep the tension of the magnetic tape approximately constant. I was doing what I was supposed to do. (For example, rVTR design latest technology data collection, edited by Japan Industrial Technology Center) Problems to be solved by the invention However, for example, in a cassette type VT'R, there is a mechanical gap between the supply reel and the means for driving the supply reel. There was a backlash, and the control gain was increased (this backlash caused a buff crash to occur, making it impossible to secure a sufficient control band and making it impossible to suppress tension fluctuations at -2 high frequencies).

In view of the above problems, the present invention provides a tape tension control device that can suppress tension fluctuations at high frequencies.

Means for Solving the Problems In order to solve the above problems, the tape tension control device of the present invention includes a first actuator means for driving a supply reel on which a magnetic tape is wound, and a first actuator means for driving a supply reel on which a magnetic tape is wound. a tape transfer means for pulling out and running the magnetic tape; a tension detection means for detecting the tension of the magnetic tape, which is disposed between the supply reel and the tape transfer means; and direct current (DC) from the output of the tension detection means.
a first filter means for extracting a component from to a first frequency (f1), a second filter means for extracting a component above a second frequency (f2) from the output of the tension detection means, a first control means for driving and controlling the first actuator means according to the output of the first filter means; a movable post disposed between the supply reel and the tape transport means; A position detection means for detecting a position, a second actuator means for driving the movable post, and an output of the second filter means are used as a position command signal for the movable post, and the position command signal and the position detection means are and second control means for comparing the outputs of and controlling the second actuator means according to the comparison result.

According to the above-described configuration, the component of the tape tension fluctuation from direct current (DC) to the first frequency (f1) is suppressed by the first control means, and the component of the tape tension fluctuation from the second frequency (f2) or higher is suppressed by the first control means. The components of the second control 'n
Since it is suppressed by means, the control band can be widened.

Embodiment Hereinafter, a tape tension control device according to an embodiment of the present invention will be described with reference to the drawings. The figure is a configuration diagram of a tape running system of a VTR using a tension control device of the present invention. In the figure, 1 is a magnetic tape, and 2 is a supply reel on which the magnetic tape 1 is wound. The supply reel 2 is driven by a first actuator means 3 via its concentric shaft 2-1. Reference numeral 4 denotes a tape transport means for drawing out and transporting the magnetic tape l from the supply reel 2. The tape transport means 4 includes a capstan shaft 4-1 that is directly rotationally driven by a capstan motor (not shown) and a pinch roller 4-2 that presses the magnetic tape 1 against the capstan shaft 4-1. The magnetic tape 1 is pulled out from the supply reel 2 and sent to the boss PI.

P2. P3. P4. P5. Tape transport means 4 via P6
The film is then wound up by a take-up reel (not shown). 5 is a tension detection means.

An arm 5-1 configured to be rotatable around a shaft 5-4 is pulled by a spring 5-2. Boss P4 is arm 5
-1, and the tension is detected by the positional fluctuation of the arm 5-1 due to the balance between the tension of the magnetic tape 1 and the spring force of the spring 5-2. A positional change in arm 5-1 is detected by position sensor 5-3.

6 is second actuator means. An arm 6-1 to which a variable post P2 is attached is connected to the second actuator means 6 via a shaft 6-2. 12 is a position detecting means for detecting the position of the variable boss P2. Reference numeral 7 denotes a first filter means, which filters direct current (DC) to a first frequency (of the frequency components of the output of the position sensor 5-3).
Components up to f1) are extracted. Reference numeral 9 denotes a first control means, which drives and controls the first actuator means 3 according to the output of the first filter means 7. Reference numeral 8 denotes a second filter means, which extracts components of a second frequency (f2) or higher from among the frequency components of the output of the position sensor 5-3. I
O is a second control means, which compares the output of the second filter means 8 with the output of the position detection means 12 as a position signal command of the variable post P2, and controls the output of the second filter means 8 so that the two values match.
actuator means 6 of the controller. Further, reference numeral 11 denotes a rotating cylinder, which records information on the magnetic tape 1 or reproduces magnetically recorded information using a mounted magnetic head (not shown).

Now, when a tension fluctuation occurs in the magnetic tape 1, the tension detecting means 5 detects the tape tension and the spring 5-.
The position of the arm 5-1 changes due to the force balance caused by the spring force No. 2. A positional change in arm 5-1 is detected by position sensor 5-3. Among the positional fluctuations of the arm 5-1 (magnetic tape tension fluctuations), frequency components below r1 including DC components are extracted by the first filter means 7 and sent to the first control means 9.

The first control means 9 increases or decreases the torque of the first actuator means depending on the output of the first filter means 7. Then, the torque of the first actuator means 3 is transmitted to the supply reel 2, and the tension of the magnetic tape 1 is increased or decreased so as to suppress the positional fluctuation of the arm 5-1. as a result,
Frequency components of tension fluctuations of the magnetic tape 1 below r1 are suppressed.

Furthermore, 12 or more frequency components of the tension fluctuation of the magnetic tape 1 are extracted by the second filter means 8 via the position sensor 5-3 and sent to the second control means 1° as a position command signal for the movable post P2. It will be done. The second control means 1O drives the second actuator means 6 in response to the output of the second filter means 8 (position command signal of the movable post P2) to change the position of the movable post P2. At this time, the position of the movable boss 1-P2 has been detected by the position detection means 12, and the second control means 10 has detected the position of the movable boss 1-P2.
2 and the output of the second filter means 8 (movable post) P
The second actuator means 6 is controlled so that the two position command signals) are equal. Further, the magnetic tape 1 is drawn out through the posts PI, P2 and P3, and a change in the position of the post P2 changes the tension of the magnetic tape 1.

That is, the second control means 10 controls the second filter means 8
The positions of the posts PL, P2 . Lengthen or shorten the regulation length leading to P3,
To suppress tension fluctuations of 12 or more frequencies of a magnetic tape 1. Furthermore, the output of the second filter means 8 is zero even for tension fluctuations at frequencies below f2, and the position of the variable post P2 is controlled. Therefore, the variable post P2 does not swing and this does not cause secondary tension fluctuations. Further, it is desirable that the second control means 10 is configured to control the position of the movable post P4 in response to a position command signal ranging from DC to a fourth frequency (f4). Here, f4>f2.

Since the DC component of the tension fluctuation of the magnetic tape 1 is suppressed by the first actuator 3 that drives the supply reel 2, the movable range of the boss P2 is small. Therefore, the second actuator means 6 can be made small. Can be configured.

Note that in order to make the frequency characteristics of tension fluctuation suppression uniform, it is desirable to configure the first filter means 7 and the second filter means 8 so that fl=f2 or fl>f2.

Effects of the Invention As is clear from the above explanation, according to the tape tension control device of the present invention, the direct current (
DC) to the first frequency (f1) is suppressed by the first control means, and the component of the tape tension fluctuation above the second frequency (f2) is suppressed by the second control means.

For example, in a cassette-type VTR, it is difficult to widen the control band sufficiently using a conventional tape tension control device due to the mechanical play that exists between the supply reel and the supply reel motor. Since the second actuator means suppresses tension fluctuations at high frequencies (frequency f2 or higher), a wide control band can be secured.

Further, since the second actuator means is feedback-controlled using the output of the position detection means, the variable post P2 can be stably controlled.
The position can be controlled. That is, when a tension fluctuation equal to or lower than the second frequency (f2) occurs, the variable post P2 does not swing (is stably positioned) (at this time, the output of the second filter means is zero). ), so
The variable post P2 does not cause secondary tension fluctuations.

In the future, when performing higher-density information recording and reproduction in cassette-type VTRs, etc., the running phase of the magnetic tape will be controlled by the magnetic head so that the magnetic head can accurately trace the trunk formed on the magnetic tape. It is conceivable to perform more precise control so as to match the phase of .

In such a case, the tension of the magnetic tape fluctuates at a high frequency, and conventional tape tension control devices cannot sufficiently suppress tension fluctuations, so the tape tension control device of the present invention is useful.

[Brief explanation of the drawing]

The figure is a configuration diagram of an embodiment of the tape tension control device of the present invention. DESCRIPTION OF SYMBOLS 1... Magnetic tape, 2... Supply reel, 3... First actuator means, 4...
... tape transport means, 5 ... tension detection means, 6 ... second actuator means, 7.
. . . first filter means, 8 . . . second filter means, 9 . . . first control means, 10.
. . . second control means, 12 . . . position detection means.

Claims (2)

[Claims] (1) The first drive that drives the supply reel on which the magnetic tape is wound.
an actuator means, a tape transport means for pulling out and running the magnetic tape from the supply reel, and a tension detection means disposed between the supply reel and the tape transport means for detecting the tension of the magnetic tape;
a first filter means for extracting a component from direct current (DC) up to a first frequency (f1) from the output of the tension detection means; and a first filter means for extracting a component of a second frequency (f2) or higher from the output of the tension detection means. A second filter means for extracting, a first control means for driving and controlling the first actuator means according to the output of the first filter means, and disposed between the supply reel and the tape transport means. a movable post, a position detection means for detecting the position of the movable post, a second actuator means for driving the movable post, and an output of the second filter means as a position command signal for the movable post; A tape tension control device comprising second control means for comparing the position command signal and the output of the position detection means and controlling the second actuator means according to the comparison result. (2) The second control means is configured to control the position of the movable post in response to the position command signal ranging from DC to a fourth frequency (f4), and f4>f2. The tape tension control device according to scope (1).