JP2683892B2 - Eccentric roll roll constant speed unwinding drive control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an original roll winding device for a central unwinding device, in which an electric motor is appropriately connected to a bobbin of an original fabric roll through a transmission device to positively unwind a film wound on the original fabric roll. The present invention relates to a feeding drive control method, and particularly to the above drive control method for positively feeding a raw roll that is eccentric to the bobbin axis at a constant speed.

[0002]

2. Description of the Related Art Conventionally, in this type of central unwinding device, an electric motor is connected to a bobbin of an original fabric roll through a transmission device, and the electric motor is controlled to be unwound at a constant tension and a constant speed. The film is being actively rolled out.

However, in general, a raw roll rolled up through a film forming process is set on a winding device in the next process such as a slitter, and is used to correct the distortion of the film wound on the roll until it is unrolled. There is a considerable storage period called aging, and during this period, the original roll often eccentric with the bobbin axis along with its own weight.

Then, when such an eccentric original roll is subsequently unwound by the above-mentioned central unwinding device, the unwinding speed fluctuates with one rotation of the roll as a cycle, causing pulsation.

Therefore, in order to absorb and reduce the pulsation of the unwinding speed, at present, a dancer roller device or the like is provided between the unwinding device and the web (film) take-up roller to absorb and reduce the pulsation. I try to pick it up at an almost constant speed.

[0006]

However, with the recent increase in speed of machines such as slitters and the like, in the above dancer roller device, the dancer roller rapidly moves up and down, which causes remarkable fluctuation of web (film) tension. Eventually, it becomes impossible to operate and hinders the high speed operation of slitters, etc., resulting in a decrease in efficiency.

The present invention copes with the actual situation as described above, and in particular, the pulsation is removed and the center winding is performed by periodically correcting the angular velocity during one revolution of the original roll in response to the eccentricity of the original roll. The purpose is to make the feeding speed substantially constant and adapt it to high-speed work such as slitter.

[0008]

That is, the features of the present invention which meet the above-mentioned object are as follows. First, when the film is unwound from the original roll which is basically eccentric with respect to the bobbin axis, the original roll is eccentric. The rotation of the unwinding roll drive motor is corrected by adding the correction based on the eccentricity of the original roll, the rotation angle at the roll center coordinates, and the phase shift of the eccentric position to the normal control rotation when not centered. The unwinding speed is controlled to be substantially constant by controlling and periodically changing the rotation speed for one rotation of the original roll.

A second aspect of the present invention is a specific embodiment of the invention, in which the unwinding drive of the original roll is performed by the formula in which the rotational speed N is expressed with respect to the normal rotational speed No when the original roll is not eccentric; N = No (1-esin (θ + ψ) / R) (however, e
Is the eccentric amount of the original roll, R is the radius of the original roll, θ is the unwinding rotation angle at the rotation center coordinates, and ψ is the phase shift of the eccentric position).

[0010]

[Operation] In addition to the control rotational movement under the control of the normal roll roller unwinding drive as described above, the correction corresponding to the eccentricity of the raw fabric and the rotation angle of the roll at the rotation center coordinates is added. The unwinding speed from the roll that is eccentric due to the eccentricity is controlled in accordance with the eccentricity amount and the rotation angle with one rotation of the roll as a cycle. It is possible to smoothly carry out the steps of pulling, cutting and winding at a constant speed even in a slitter or the like.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the present invention will be described below.

FIG. 1 shows an example of a basic control circuit of the present invention, and FIG. 2 shows the principle of determining a predetermined rotation speed of the unwinding shaft in the control circuit.

In FIG. 1, A is an original roll having an eccentricity e with respect to the axis of the bobbin B, R is its radius, and M is a motor for unwinding the original roll A. The film F wound on the original roll A is unwound by the dancer roller device 1 after the fluctuation of the unwinding speed is absorbed and relaxed. Reference numeral 3 is an air cylinder, 4 is a displacement detector, 5 is a take-up motor, 6 is a tachometer for measuring the line speed, and the fluctuations at the time of unwinding are detected by these respective devices.
It has been generally performed and is known in the art that the absorption and relaxation are performed by moving up and down. Then, at this time, the unwinding drive motor is rotated by the series speed of N by the line speed V of the take-up motor 5 detected by the tachometer 6, the dancer correction speed ΔV, and the diameter of the original roll A.
o (No. of revolutions when the original roll has no eccentricity) is V
/ 2πR, which is given to the unwinding drive motor M to rotate the motor M. However, at this time, the rotation speed of the motor M is controlled in consideration of the correction speed (ΔV) detected by the dancer roller device 1. Reference numeral 19 is a tachometer of the motor M.

However, in the present invention, the original roll A is a roll in which the axis of the bobbin B is eccentric by the eccentric amount e,
The pulsation cannot be eliminated by the unwinding drive with the above-described rotation speed No. This is due to the eccentricity of the original roll A. Therefore, some kind of correction is necessary to keep the unwinding speed substantially constant.

In FIG. 1, 11 is a core rotation angle detector such as a rotary encoder, 12 is a fixed sensor such as a laser change meter, 13 and 14 are operational amplifiers, 15 and 16 are arithmetic units, 17 is an adjustable inverter, and 18 Are amplifiers, respectively, which form a correction circuit, and which have
Correction is added to o.

The principle of determining the required number of rotations of the unwinding shaft by the above correction will be described with reference to FIG.

Now, when the original roll A having eccentricity is unwound in the tangential direction of the roll outer periphery at the point P as shown in FIG.
2R is the diameter of the original fabric, e is the amount of eccentricity with respect to the unwinding center of the original fabric, θ is the rotation angle of the roll, and γ is the point P (moves on the abscissa XX axis depending on the eccentric position). , The rotation center ordinate is the distance from the Y-Y axis, that is, the radius of gyration at any position, and when the eccentricity e is small with respect to the original roll diameter, the relationship of γ to the rotation angle θ of the roll is is there.

[0018]

[Formula 1] γ = R + esin θ (1)

When operating at the line speed V (constant), the rotation speed N of the unwinding shaft corresponding to the eccentric position for preventing slackening or extension is as follows.

[0020]

[Formula 2] N = V / 2π (R + esin θ) (2)

On the other hand, the number of revolutions No assuming no eccentricity is

[0022]

[Equation 3] No = V / 2πR (3)

## EQU1 ## In both cases, the line speed V must be the same,

[0024]

[Equation 4] 2π (R + esinθ) · N = 2πR · No ... (4)

Therefore,

[0026]

## EQU00005 ## N = No / (1 + esin.theta. / R) (5)

However, the eccentricity e is much smaller than the original roll diameter R (actually, the original roll diameter is 400 to 600 m).
With respect to m, the eccentricity is 10 mm or less. ) Esin θ /
Since R is extremely small compared to 1, the binomial series expansion is performed, and if minute terms are omitted, the rotational speed N is approximately

[0028]

[Equation 6] N = No (1-esin θ / R) (6)

## EQU1 ##

As is clear from the above, the equation (6) is divided into the number of revolutions No when there is no eccentricity and (-Noesin θ / R) which is a correction term due to eccentricity. Of these, the former means normal unwinding shaft rotation control when the eccentricity of the original roll is not considered. Actually, the correction speed (ΔV) detected by the dancer roller device is added to the above basic circuit. Therefore, it is sufficient to add the latter as an independent correction amount based on this. FIG. 3 shows the situation.

Applying the mode in which the correction obtained based on the above principle is added to the correction circuit shown in FIG.
Let L be the distance from the axial center of the original roll A to the fixed sensor 12, and let l be the distance from the fixed sensor 12 to the surface of the original roll A. Let the initial rotation angle obtained by the angle detector 11, that is, the eccentric position be If θ is set, the operational amplifier 14 determines the distance 1 from the sensor to the roll surface and the initial rotation angle θ.
While inputting a signal based on the above, the distance l is input to another operational amplifier 13 and the rotation angle θ of the angle detector 11 is input to detect the deviation angle ψ of the eccentric position during operation. Further, Nosin (θ + ψ) is calculated by the arithmetic unit 15 by inputting the output of the rotation angle θ of the angle detector 11 to the arithmetic unit 15 and the rotation speed No when there is no eccentricity.

On the other hand, the output roll diameter R and the eccentricity e of the output obtained from the operational amplifier 13 are input to the arithmetic unit 16, and the output thereof is + -inverted by the inverter 17 and input to the amplifier 18.

In addition to the signal based on the original roll diameter R and the amount of eccentricity e, the signal calculated by the calculator 15 is also input to the amplifier 18 together with the normal rotation speed No. Unwinding drive motor M as corrected rotation speed N
To achieve the object of the present invention.

FIG. 4 shows the above-mentioned control circuit constituted only by an electric system, and its operation mode is the same as that explained in the basic control circuit of FIG. In the figure, 13 'is an operational amplifier,
16 'is an arithmetic unit. In this case, the diameter R of the original roll and the amount of eccentricity e are calculated by the following equation per rotation.

[0035]

## EQU00007 ## R = [(L-lmin) + (L-lmax)] / 2 e = (lmax + lmin) / 2

Further, ψ is a phase shift at the eccentricity max position. If ψ is 0, there is only the initial rotation angle θ.

FIG. 5 shows a control circuit composed of both an electric system and a mechanical system. The normal average rotation speed No is a closed loop which is the same as that shown in FIG. 4, but No.times.sin (.theta. +).
ψ) is synchronized with the rotation of the unwinding shaft and mechanically performed by using the eccentric cam K.

Also in this case, the operation mode is as shown in FIG.
The details are omitted because it is similar to the description based on the above.

Thus, in the present invention, even if the original roll is eccentric with respect to the axis of the bobbin, the average number of revolutions is corrected according to the amount of eccentricity and the rotation angle of the roll at the coordinates of the rotation center, and one revolution of the roll is performed. On the other hand, the rotation speed can be changed periodically to unwind the film at a substantially constant speed.

The present invention is particularly suitable and effective when the eccentricity of the original roll is not so large and the winding does not collapse even if the number of revolutions within one revolution of the roll is periodically changed.

[0041]

As described above, according to the present invention, when the film is unwound from the original roll which is eccentric with respect to the center of the bobbin axis, the normal control rotational speed when not eccentric is the eccentric amount and the eccentric position on the rotational coordinate. This is a method of periodically correcting the angular velocity during one rotation of the roll to make the unwinding speed of the film substantially constant. In the conventional unwinding, the speed fluctuation that often occurs due to the eccentricity of the original roll Even if the original roll has eccentricity, it can be unrolled at a constant speed to allow smooth unwinding, and it can handle the speed of the slitter sufficiently. It is extremely effective in improving the work efficiency and product quality of a slitter or the like having a step of taking out.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic control circuit of the present invention.

FIG. 2 is an explanatory view of the principle of determining the rotation speed of the unwinding shaft in the control circuit.

FIG. 3 is an explanatory diagram of a combined state of rotation control in the present invention.

FIG. 4 is a block diagram showing an example of a control circuit according to an embodiment of the present invention.

FIG. 5 is a block diagram showing another control circuit example according to an embodiment of the present invention.

[Explanation of symbols]

 A original roll B bobbin F film No normal average speed without eccentricity N required speed e according to the invention e eccentricity θ rotation angle

Claims (2)

(57) [Claims] 1. When the film is unwound from an original roll that is eccentric with respect to the axis of the bobbin, the eccentricity of the original roll and the roll amount relative to normal control rotation when the original roll is not eccentric By controlling the rotation of the unwinding drive motor of the original roll by adding the correction based on the rotation angle in the rotation center coordinate and the phase shift of the eccentric position, the rotation speed is changed periodically for one rotation of the original roll. A uniform speed unwinding drive control method for an eccentric original roll, characterized in that the unwinding speed is made substantially constant. 2. The unwinding drive of the original roll is performed by the following formula: N = No (1-esin (θ + ψ) / R) with respect to the normal rotational speed No when the original roll is not eccentric.
(Where e is the eccentric amount of the original roll, R is the radius of the original roll, θ is the unwinding rotation angle at the rotation center coordinate, and ψ is the phase shift of the eccentric position). Eccentric roll roll constant speed unwinding drive control method.