DD279148A3 - METHOD AND ARRANGEMENT FOR ACCELERATING A REPLACEMENT WINDING ROLL - Google Patents

Abstract

The invention relates to a method and an arrangement for accelerating a replacement winding roll in unwinding devices for web-shaped material and is particularly applicable in printing press construction. The drive takes place with a selectable, constant tangential acceleration. Thus, the acceleration time and the moment of inertia of the replacement winding roll can be calculated in good time. The arrangement includes a drive control with a setpoint generator for acceleration and a computing and storage unit, are connected to the transducers for the peripheral speed, speed and path velocity, the setpoint generator for acceleration and a current transformer in the current path of the actuator of the drive. Fig. 1

Description

-2- 279148 Presentation of the Essence of the Invention

The invention has for its object to provide a method for accelerating a replacement winding roll in unwinding devices for web-shaped Good, in which the acceleration is drive-controlled, which ensures the timely determination of the acceleration time of the replacement winding roll and their Massenträgiieitsmomentes and protects the adhesive tip. In addition, an arrangement for carrying out the method to create.

According to the invention the object is achieved in that the drive is done with selectable, held constant tangential acceleration.

This makes it possible to calculate the required acceleration time of the replacement winding roll at any given time to the existing web speed of the processing machine according to a very simple mathematical relationship e ^ akt. The thus determined in time acceleration time makes it possible to set the acceleration start of the replacement winding roll optimally, so that prevents the accelerated role to bond unnecessary rotations performs or the role reaches the web speed too late and the old role is used up before the execution of the bond , This prevents false bonds with waste accumulation and machine downtimes.

The ancestor according to the invention also makes it possible, at the beginning of the acceleration process, to determine the mass moment of inertia of the replacement winding roll. Thus, in the case of a stop braking during startup, the braking torque can be metered as a function of the mass moment of inertia. In the case of a small winding roll, the adhesive sleeve is thereby spared in peripheral drive and the winding sleeve is spared in the case of center drive and the risk of false gluing, machine downtimes, reduced printing speed or roller separation is reduced. From the moment of inertia, the roll mass can also be determined easily and is, for. B. for process data acquisition of the processing machine available.

Finally, the acceleration of all replacement winding rolls with the same tangential acceleration has the advantage that even with small bobbins, the adhesive tip is not exposed to increased inertial force and thus the risk of lifting. The proposed method is advantageous in an arrangement with a controlled drive for the replacement winding roll with the series connection of a transducer for the peripheral speed of the replacement winding roll, a control device and a speed controller, which is in communication with the actuator of the drive, wherein in the current path a current transformer is, as well as with a computing and storage unit, which is fed by transducers for the peripheral speed and speed of the spare reel and a transmitter for the web speed, realized if present invention at the setpoint input of the controller, a setpoint generator for acceleration and this also applies the current transformers are connected to the computing and storage unit.

embodiment

The invention will be explained in more detail below on some embodiments. In the accompanying drawings show:

1: the block diagram of an arrangement for accelerating a replacement winding reel with belt drive FIG. 2: the block diagram of an arrangement for accelerating a replacement winding reel with center drive FIG. 3: the diagram of the time profile of the voltage U at the output of the digital Ar .alog converter 19 or 46 of FIGS. 1 and 2.

The acceleration assembly shown in Fig. 1 includes a two-armed roller stand 1, which carries the old winding roll 2 and the ErseU winding roll 3. From the old winding roll 2, the material web 4 is unwound and the processing machine, for example, a printing press supplied. The web drives a web guide roll 5 with a web pulse generator 6, which is connected to a computing and storage unit 7. Each arm of the roll stand 1 carries a revolution pulser 8; 9, which emits a pulse per revolution. Mitteis a switching device 10 each belonging to the replacement winding roller revolution pulse, in the drawing so the rotation pulse generator 8, connected to the computing and storage unit 7. At the replacement winding roll 3 is a drive belt 11, which is in drive connection with a DC motor 12. With the latter, a tachogenerator 13 and a circumferential encoder 14 are further coupled. While the circumferential pulse generator 14 is connected to the arithmetic and processing unit 7, the tachogenerator 13 is connected to the actual value input of a control unit 15. At its setpoint input, a potentiometer 16 is connected, wherein in series a voltage-Frequer z-converter 17, a counter 18 and a digital-to-analog converter 19 are zwischengoschaltet. The potentiometer 16 is further connected to the computer and spoiler unit 7. The control device 15 is followed by a speed controller 20 whose output is guided on the DC motor 12 as an actuator. in Anker.stromkreis the DC motor 12 is a current transformer 21, which is connected with the interposition of a current-voltage converter 22 to the arithmetic and Speichoreinheit 7. Furthermore, the control device 15 is connected to the computing and Speii'hereinhoit 7 in connection

 In the further explanations, the symbols used have the following meaning:

a, tangential acceleration

a, B, tangential delay

D Diameter of the replacement winding roll

f function

In the armature current of the acceleration motor

Jg Mass inertia of the belt drive

Jk Moment of inertia of roller bearing (cone)

Jr Mass moment of inertia of the spare winding roll

Jz mass moment of inertia of the Zontrum drive

K, to K ₉ constant Like Drive torque with belt drive Maz Drive torque at center drive Mb, g Braking torque for belt braking Μβ, ζ Braking torque for center brake mr Frictional torque of the roller bearing mrg Frictional torque of the belt drive m Mass of replacement winding roll N Way per single pulse η Speed of the acceleration motor S Bshnweg per Bahnimp ¹¹¹ S tv time interval t. ßeschleunigungszeit U tension AU voltage stage Vb web speed Vu circumferential speed Z _B Number of path pulses Z ₀ Number of revolution pulses To Number of circumferential pulses α rise angle V frequency ω Angular velocity of the acceleration motor

In the course of a role change process not to be described in more detail, the replacement winding roll 3 is to be adhered to the material web 4 of the old wound roll 2 that is going to end. For this purpose, the replacement winding roller 3 is accelerated by means of the DC motor 12 in its peripheral speed Vj from zero to the web speed v _a . This is done with a constant tangential acceleration a ,, which is preselected and set as a voltage value on the potentiometer 16. This voltage is once the computing and storage unit 7 zugeleite '. It is further converted in the voltage-frequency converter 17 in an equivalent frequency ν . The frequency signal is supplied to the counter 18, which increases its count due to the incoming pulses. In the counter 18 downstream digital-to-analog converter 19, the current count is converted into an equivalent voltage U. This results in the output with continuous increase of the count a corresponding to the voltage levels AU of the digital-to-analog converter 19 approximate Rampenfunküor », whose increase is determined by the count frequency of the counter 18 (Figure 3) and the tangential acceleration a, embodied. It applies

a _t = tana = (1)

At

or a, = AU · •. (2)

The ramp function is supplied as a reference variable of the control device 15. The latter will continue to supply the tension of the tachogenerator 13 as a measure of the peripheral speed of the spare winding rollers 3. The control device contains the necessary for the optimization of the control transfer functions. The output signal is supplied to the speed controller 20, which provides a variable voltage for the DC motor 12 and thus causes the necessary speeds for the drive.

Due to the linear increase in circumferential speed increase per unit time, which is linear with constant tangential acceleration, the required acceleration time t _{a of} the replacement winding roller 3 results from the relationship

Vb

t _a = (3!

^a i

or ta = K ₁ · v _B (4)

with K ₁ = - (5)

a ₍

as a constant.

The path velocity v _B is calculated in the arithmetic and storage unit 7 from the number of path pulses Z _{B of} the path pulse generator 6 over a predetermined time interval T _v and the path S per path pulse according to the equation

Z ₈ p

Vb = - (6)

tv

determined.

For the drive torque Mag of the acceleration motor for belt drive applies:

4Jr a, 4J _K a,

^Yes ^ ⁺⁺⁺

₂ α »

Vu Vg.

From equation (7), the moment of inertia Jr of the replacement winding roll 3 is increased

M _AG · D ^; · K ₂ M _RG · D ² K ₂ J ₀ · D ² · Kj M _R D

4a, 4a, 4 2a,

The drive torque Mag is a known function of the armature current Im of the DC motor 12,

. "'ag =" im). (10)

The value of the armature current Im is supplied to the current transformer 21 and converted by means of the current-voltage converter 22 into a voltage supplied to the arithmetic and storage unit 7

 With equation (10) and the constants

K ₃ = -y- (11)

K ₄ =

K ₅ - ^. (13)

mr

K ₆ = -y- (14)

K ₇ = Jk (15)

Equation (9) can be transformed

1J <e_p_

"" ⁵ J ' ^D ~ a, ~ ^K ' -

Jr ^m = ^J --K ₅ D ² - -K. ₇ (16)

L a _t ! a,

The constants are specific to the roll-off, as well as the function of the armature current is fixed, and the tangential acceleration a, is given. The initial diameter D of the spare reel 3 at its first rotation is made up of the number of circumferential pulses To of the perimeter encoder 14 between 2 pulses Z _{0 of} the revolution pulser 8 and the circumferential path N per circumferential pulse according to the equation

_{D =} _Zyj_N_ ₍₁₇₎

determined in the arithmetic and memory unit 7. Thus, it is now possible by means of the latter to calculate the mass moment of inertia Jr.

At the same time, the mass m of the replacement winding roll 3 is calculated too

8J _n

(w

and can be utilized, for example, for process data of the processing machine.

With the presentation of the mass moment of inertia Jr is analogous to the components acting during acceleration, the braking torque M _B , o for Gurtbremsung the replacement winding roll calculated to

MM 4 ι u κ 4J _R a, _B , 4Jk a, _B , 2M _R

M _B , G = -Mrq + J ₀ · d, B, · K ₂ + + - (19)

wherein the tangential delay a, ß, is specified. In the case of a stop braking, the calculated by the computing and storage unit 7 Bremsmome.it M _b , g in the form of a voltage of the control device 15 is supplied. The latter then aborts the acceleration control of the replacement reel 3 and controls the speed controller 20 so that the working in four-quadrant DC motor 12 generates the braking torque.

In the exemplary embodiment, the acceleration of the replacement winding roll takes place by means of a motor. The invention can also be used, for example, when the drive of the replacement winding roll from the main drive of the processing machine z. B. via an electric clutch as an actuator. It is then the corresponding dependence of the transmitted torque of the clutch from the excitation current and the proportion of the clutch on the moment of inertia Jg changed constant K ₅ entered into the computing and storage unit.

In Fig. 2, an accelerator assembly is shown which includes a two-armed roller stand 23. The latter carries d.'q old winding roll 24 and the replacement winding roll 25. From the old winding roll 24, the Materinibahn 26 is unwound and u. a. guided over the web guide roll 27, which carries a connected to a computing and storage unit 28 web pulse 29. On the winding roller spindle 30 of the spare winding roller 25, a DC motor 31, on the winding roller spindle 32 of the old winding roller 24 engages a DC motor 33. Each arm of the roller stand 23 carries a revolution pulser 34; 35, which emits a pulse per roller revolution. By means of switching devices 36; 37 each of the replacement winding roll associated DC motor and revolution pulse are effective. In this case, in FIG. 2, the revolution pulse generator 34 is connected to the computing and storage unit 28 and the DC motor 31 to the output of a speed controller 38. On the shell of the spare winding roller 25 is located on a roller 39, with a connected to the computing and storage unit 28 peripheral encoder 40 and a tachogenerator 41 are coupled. The latter is connected to the actual value input of a control device 42. At its setpoint input, a potentiometer 43 is connected, in series, a voltage-frequency converter 44, a counter 45 and a digital-to-analog Wandier 46 are interposed. The potentiometer 43 is still connected to the computing and storage unit 28 in connection. The controller 42 is the speed controller 38 downstream. In the armature current path for the DC motors 31; 33 is a current transformer 47, which is connected with the interposition of a current-voltage converter 48 to the computing and storage unit 28. With the latter is still the controller 42 in conjunction.

In the course of the reel change operation, the replacement reel 25 is to be adhered to the web 26 of the ending old reel 24. For this purpose, the replacement winding roller 25 is accelerated by means of the DC motor 31 in its peripheral speed vu ° 'on zero to the web speed V ₈ . This is done with a constant tangential acceleration?., Which is preselected and set as a voltage value at the potentiometer 43. This voltage is once the arithmetic and memory unit 28 fed. It is further converted in the voltage-to-frequency converter 44 into an equivalent frequency ν. Dns frequency signal is supplied to the counter 45, which increases its count due to the incoming pulses. In the counter 45 downstream digital-analog Wandier 46, the current count is converted into an equivalent voltage U. Thus arises at the output with continuous increase of the count a corresponding to the voltage levels AU of the digital-to-analog converter 46 approximate ramp function whose increase is determined by the count frequency of the counter 45 (Figure 3) and the tangential acceleration a · embodies. It applies

a, = tana = - (1)

or a, = AU · »Ί (2)

The ramp function is supplied to the control device 42 as a reference variable. Finally, the voltage of the tachogenerator 41 is fed as a measuring width for the peripheral speed of the replacement winding roller 25. The control device 42 contains the necessary for the optimization of the control transfer functions. The output signal is supplied to the speed controller 38, which provides a variable voltage for the DC motor 31 and thus causes the necessary speeds for the drive.

For the determination of the acceleration time t _{a of} the replacement winding roller 25, the equation (4) applies analogously to the first embodiment.

t. = K ₁ v _B (4)

with K, = - (5)

a _t

as a constant.

Similarly, the orbital velocity v _B according to equation (6)

Z _B S Vb = - (6)

from the number of path pulses Z _{8 of} the track pulse generator 29 over a predetermined time interval T _v and the path S determined per path pulse.

For the Aniriebsmoment Maz of the acceleration motor at center drive applies

2J _R a, 2 (J _Z + Jk) · a,

+ - ^ - - + M _n . (20)

Ma ₂ +

D D

From equation (20), the mass moment of inertia J _{R of} the spare winding roller 25 is given

DM _R · D

^{J J}

In this case, the drive torque Maz is a known function of the armature current Im of the DC motor 31,

Μ «= f (U. (22)

The value of the armature current I _M is supplied by the current transformer 47 and converted by means of the current-voltage converter 48 into a voltage supplied to the arithmetic and storage unit 28

 With equation (22) and the constants

mr

K ₈ = - (23)

K ₉ = J ₂ + Jk (24)

Equation (21) can be transformed into «• m) J O ..

^r - L

: ₉ . (25)

The constants K ₈ and Kg are specific to the deceleration, as well as the function of the armature current is fixed, and the tangential acceleration a, is given. The initial diameter D of the spare winding roll 25, as in the belt-driven accelerator, during the first reel rotation according to Equation (17).

From the number of circumferential pulses to the circumferential encoder 40 between 2 pulses Z ₀ of the Umdrehungsimpulsgebers34 and the circumferential distance N per perimeter pulse in the computing and storage unit 28 determined. Thus, the mass moment of inertia J _R can now be calculated by the latter according to equation (25). At the same time, the mass m of the replacement winding roll 25 can also be calculated according to equation (18).

(18)

With the presence of the mass moment of inertia Jr, the braking torque M _B , z for center braking of the replacement winding roll 23 is calculable analogously to the components acting during acceleration

2J _R · a «, 2 (J _Z + Jk) · a, M _B , z = + Mr, (26)

wherein the tangential delay a, B, is specified. In the case of a stop braking, the calculated by the computing and storage unit 28 braking torque M _BfZ in the form of a voltage of the control device 42 is supplied. The latter then aborts the acceleration control of the replacement winding roll 23 and controls the speed controller 38 so that the four-quadrant as as processing DC motor 31 generates the braking torque.

In the embodiments, the roll stand each carry two arms. The invention is also applicable to three-armed roller stands.

Furthermore, using the invention, the computing and storage unit can also be fed by analog sensors. Also, the transmitter for the speed of the spare reel can deliver one pulse train per revolution, then in formula (17) still receives the ratio of the pulses per revolution and the evaluated pulses as a factor. Likewise, the detection of the processing device to be processed by the speed behavior of the replacement winding roll with a digital encoder is possible. Also, the controller and the arithmetic and storage unit may be connected to a common peripheral circumferential speed sensor of the spare reel. With appropriate selection of the control device and the counter downstream of the digital-to-analog converter can be omitted.

In the embodiments, a potentiometer serves as a setpoint generator for the tangential acceleration. For this purpose, another variable DC voltage source can be used. However, it is also possible for the soli value of the tangential acceleration to be stored in the arithmetic and storage unit and to be supplied by it to the voltage-frequency converter.

Claims (3)

1. A method for accelerating a replacement winding roll in unwinding devices for web-shaped Good, wherein the acceleration is driven controlled, characterized in that the drive with selectable, held constant tangential acceleration Ia ₁ ). 2. An arrangement for accelerating a replacement winding roll in unwinding devices for sheet material with a regulated drive for the replacement winding roll with the series connection of a peripheral speed sensor of the spare winding roll, a control device and a speed controller, with the actuator of the drive in combination stands, in whose current path is a current transformer, as well as with a computing and storage unit, which is fed by transducers for the peripheral speed and speed of the spare reel and a transmitter for the web speed, characterized in that at f ollwerteingang the controller a setpoint generator for acceleration and this also and the current transformer (21; 47) to the computing and storage unit (7; 28) are connected. For this 3 pages drawings Field of application of the invention The invention relates to a method and an arrangement for accelerating a replacement winding roll in unwinding devices for web-shaped material in web-processing machines, in particular jre rotary printing presses. Characteristic of the known state of the art In unwinding devices with automatic roll change, the determination of application points of roll change steps u. a. Requires the required time to accelerate the Ersdtz reel from zero to web speed. Acceleration usually takes place at a constant torque (eg EP application 18555). Here, the required acceleration time depends not only on the height of the web speed to be achieved, but also on the size of the replacement winding roll. This time is fixed in a known control arrangement (DE-PS 2619236). For the following reasons, however, the required acceleration time should be as accurate as possible. If the acceleration rate is too high, the replacement reel sped up to the web speed of the printing press will perform additional rotations until this time has elapsed. This increases the risk that solves the adhesive tip prepared for the gluing of the winding roll and a Fehlklebung done or canceled the Rollenwechsolvorgang and the gluing must be carried out by hand. On the other hand, if the acceleration time actually required is greater than the intended, then the gluing process subsequent to the acceleration is initiated late, which may have the result that the roll remainder of the unwinding old winding reel before execution of the Anklebung is used up and the automatic gluing fails. In all cases there are machine downtime and waste. It is also advantageous to unwinding the knowledge of the moment of inertia of the replacement winding roll. According to EP Application 18555 this is calculated from the measured time for the acceleration of the replacement winding roll at web speed. It is disadvantageous that the moment of inertia to achieve a controlled braking torque of the replacement winding roller is not yet available in the case of a stop braking during the acceleration process. Thus, in the stop braking of a small winding roll with an unnecessarily large braking torque in arrangements with belt drive the adhesive tip and in arrangements with center drive the sleeve on the cone heavily loaded. In the former case, the shift of the glue tip threatens and as a result a Fehlklebung. The second case may require further pressure with reduced web speed due to damage to the winding tube or even lead to the rejection of this role with concomitant pressure interruption. Another disadvantage is that the Beschü ·, iiig.ung the replacement winding roll is carried out with a constant torque. In a small replacement winding roll uif adhesive tip is thus heavily loaded, which can lead to their lifting with the consequences mentioned above. Object of the invention The object of the invention is to provide a method and an arrangement which avoid misapplications and thus reduce the accumulation of waste and machine downtimes.