EP2019063A2 - Method and device for optimising lateral processing procedures - Google Patents

Abstract

The method involves selecting a desired format for material section. A number of laws of motion are supplied for controlling a rotative movement of a transverse machining roller (110) in a control device (150). The desired format supply or computation of a movement of the transverse machining roller is provided on the basis of the law of motion in the control device or a parameter of a drive (140) or a default of a user. Independent claims are also included for the following: (1) a transverse machining device for executing the method (2) a computer program with a program coding unit (3) a computer program product with a program coding unit.

Description

The invention relates to a method and a device for optimizing cross-processing operations, a corresponding computer program and a corresponding computer program product.

State of the art

Cross-processing applications, d. H. Applications in which, for example, a material web is cut through by means of a rotary cutter are known in general. Another example of cross-processing applications or cross-processing devices are transverse sealing devices, Querperforationsvorrichtungen and cross-punch devices.

A machined, for example, severed section length is not necessarily identical to the scope of the transverse machining roller used. By a suitable choice of laws of motion for the cross-machining roller can be achieved that in a typical material web synchronous machining operation is performed in the cut, and in the remaining time range, a so-called compensatory movement is performed. This compensatory movement serves this purpose; a shorter or longer format (section length) than the so-called synchronous length, which corresponds to the circumference of the cross-processing roller reach.

The movement profile of the cross-processing roller looks different depending on the ratio of format length and synchronous length. With a format length smaller than the synchronous length, the axis of rotation of the cross-processing roller must be faster during the compensating movement, in the opposite case, d. H. larger format length, slower.

To carry out the compensating movement, a polynomial of the fifth order, or possibly also of a higher order, according to VDI regulation 2143 "laws of motion for cam mechanisms" is typically used.

In the case of format lengths which are substantially greater than the synchronous length, for example two and one-half times as large, it may be desirable for the cross-processing roller to partially rotate at negative speed, i. opposite to the direction of transport of the items to be transported and processed, e.g. to be cut material web. This equals a backward movement.

Depending on the format, the backward movement becomes ever larger, and would eventually become so great at longer formats that the knife provided on the cross-processing roller would again plunge into the cutting zone and thus possibly also into the material. Of course, this should be avoided.

In this connection, ways are known from the prior art to prevent such reverse rotations. Typically, any negative velocity is excluded.

This ensures that the rotational speeds of the cross-processing roller at all times assume a positive sign or at least a standstill zone, i. negative speeds are avoided, it is limited to a maximum standstill. Depending on the desired format, it may be due to drive limitations, e.g. maximum speed or maximum torque or maximum acceleration of the cross-processing roller, in addition, a maximum speed can not be exceeded. This maximum speed depends on the used motion law of the compensation movement. In the prior art, such a maximum speed is measured once, and then deposited as a fixed value table in the machine control or the HMI (Human Machine Interface).

In the case of a format change, conventional devices require the operator to adjust the machine speed to the maximum speed of the new format. This means that, if necessary, it must reduce the machine speed before a so-called flying format change, so that any limitations of the drive in the new format are not exceeded. In such a case z. B. the drive report an overload error and initiate an error response that would lead to the abort of production. An increase in the machine speed after a format change is also conceivable, but must also be carried out manually by the operator in conventional devices.

Laws of motion used in the prior art are designed to achieve the highest possible machining performance (machine speed). No consideration is given to energy issues.

Furthermore, in the prior art only fixed laws of motion are used for each format. A maximum of one switching to a law of motion without backward movement is performed. In addition to considering whether a backward movement is permitted or not, further laws of motion for optimizing the acceleration, the maximum speed and / or the loss energy are possible. There are no format-dependent switches to different movement types, such. For example, fifth order polynomial, seventh order polynomial, modified sine, modified acceleration, etc. are performed.

Furthermore, in conventional devices or methods, the achieved accuracy in the machining or cutting area is not monitored by the drive system. In particular, at higher speeds or higher dynamic compensation movements lag errors (deviation between position actual value and position setpoint) may occur, which reduce the machining accuracy.

In particular, it is considered disadvantageous in conventional devices or methods that the compensating movement is always counted as an identical law of motion. As a result, optimizations, for example, with respect to maximum speed or energy consumption can hardly be achieved.

According to the prior art, a reverse rotation of a cross-processing roller is not used because of each Case is to be avoided that a processing element, such as the cutting knife, dips backwards into the material. Due to the fact that the possibilities of a reverse rotation are not utilized, the drive is not operated optimally with regard to realizable maximum speeds or energy consumption. The same applies to a limitation of the roller speed a value greater than or equal to zero.

Furthermore, in the case of a format change in conventional devices, the new, adapted to the format now to be realized maximum speed can not be calculated automatically. This leads to complex test drives and deposit of fixed characteristics in the control.

Overall, it should be noted that in formats for which the maximum drive torque is not achieved, optimized energy consumption can not be achieved.

task

The present invention seeks to overcome the disadvantages described above, i. H. in particular to make it possible to utilize a maximum drive torque, in particular while optimizing energy consumption.

The invention therefore proposes a method with the features of claim 1.

Advantages of the invention

With the method according to the invention an optimization of the throughput of a cross-processing device can be realized, wherein loss-optimal curves for energy saving can be selected in particular by a predicted calculation of achievable machine speeds. Furthermore, with the method according to the invention a great machining accuracy can be achieved. By knowing drive limits, for example maximum speed, maximum acceleration or even thermal limits, the maximum achievable machine speed or material web speed can be calculated in advance.

Advantageous embodiments of the method according to the invention are the subject of the dependent claims.

It is particularly preferred that the method for operating a cross-cutting roll, a transverse sealing roll, a transverse perforation roll, a cross-roll of a cutter device, a transverse sealing device, a Querperforationsvorrichtung or a transverse punching device is used. In such devices appropriately tailored, sealed, perforated or stamped web portions are provided.

It is preferred that the parameters of the drive, which enter into the calculation of the permissible maximum web speed, a maximum drive or engine torque, a maximum drive or engine temperature, a maximum drive or engine speed, an estimate of occurring cutting forces and mechanical conditions, such as moments of inertia or mechanical translations.

Furthermore, it is possible, in particular online, to determine the machine speed by evaluating thermal continuous power limits, such as engine temperature or temperature Drive controller, and thereby optionally achieve an optimization of the cutting performance. In particular, the cutting torque, which is dependent on the material of the web, sometimes can not be specified in the prior art, so that this aspect can be optimized by the online monitoring and optionally learned for later identical or similar productions. Online monitoring is understood to mean, in particular, monitoring during the process by comparison with calculated models.

Such an online calculation or monitoring is also applicable when changing a format-dependent motion law or a corresponding algorithm to be used. There are no time-consuming test drives over the entire format range necessary. Productivity can be optimized due to the maximum machine speed that can be displayed. Furthermore, a dynamic consideration of thermal models for the motor and / or the drive controller is taken into account.

According to the invention, it is possible, in particular, to adapt the current machine speed to a new maximum machine speed for a new format during a format change.

In the prior art, this is done by adjusting the machine speed via the HMI (input by the machine operator).

If the maximum machine speed is known due to a calculation or provision according to the invention (stored characteristic), the machine speed can be automatically determined by the controller in the case of a Formatwechsel be suitably reduced and / or increased. In particular, it is expedient to provide a reduction in the machine speed before the format change, or an increase in the machine speed subsequent to the format change.

If the maximum machine speed is limited by thermal limits, for example the maximum continuous current load of the motor or drive control device, the reduction of the machine speed can also take place after the format change, provided that the thermal behavior is taken into account. A short-term increase in the machine speed over a permanently permissible maximum speed is permitted, as long as the thermal limits are not exceeded.

This reduces the input effort for the user in the case of a format change. Furthermore, this allows an optimization of productivity, i. the maximum machine speed, through thermal optimization.

In particular, in the event that longer formats, ie formats which are longer than the circumference of the cross-processing roll, are desired, the maximum machine speed is no longer limited by the drive system, but typically by the process itself. Here, for example, to refer to maximum feed rates of webs. This means that the drive system can in principle execute any compensation movement laws. These can now be selected according to the invention such that the lowest possible energy consumption arises. The energy consumption can be determined, for example, based on the square of the acceleration of the drive and / or the cross-processing roller or be estimated. This makes it possible to minimize energy loss, whereby the energy costs for the inventive operation of a cross-cutting device are minimized. Furthermore, the thermal adaptation of motor and drive controller or drive controller to each other proves to be advantageous.

The provision according to the invention of format-dependent different laws of motion also allows them to be optimized according to various criteria. Examples of criteria are, for example, the energy consumption of the compensation movement, which is particularly small in the description of the movement of the transverse processing roller by means of a 3rd degree polynomial, for example.

Also, for optimizing the maximum speed, for example, polynomials of the third degree or sinoids prove to be advantageous.

It is also possible to optimize the laws of motion with regard to protecting the mechanism, in particular the drive and / or transverse processing roller, in particular used gears. For this purpose, modified sinusoidal lines, for example Bestehorn sine lines with low jerk characteristic values, are available. For example, it is also possible to select the laws of motion with regard to minimizing the maximum occurring accelerations. For this, polynomials of the 2nd degree are suitable.

According to a particularly preferred embodiment of the method according to the invention, a compensation movement of the cross-processing roller is calculated by means of a format-dependent law of motion, which in particular a permissible reverse rotation of the cross-processing roller in a Direction opposite to the transport direction of the web comprises.

Such a reverse rotation can be predetermined in particular as an angle value, the compensation movement being limited to this value. Depending on the mechanics, the width of the backward movement can be specified. The backward movement can thus (in the limiting case) take place exactly up to the cutting area. This allows maximum stopping and acceleration paths, resulting in a significant reduction of the maximum occurring accelerations.

By means of these measures, the applicable laws of motion can be selected energy-optimized, in which case, in particular, heating, energy consumption and motor or amplifier size can be taken into account. The laws of motion used can be optimized for the maximum moment, e.g. the maximum speed of the feed or the drive or motor or amplifier size. The selected law of motion can also be optimized to protect the mechanics, which, for example, a lower noise is feasible.

It also proves to be useful to provide a monitoring of the cutting accuracy in the cutting region of the cross-machining roller. In particular, online monitoring has proven to be advantageous.

One goal of a cross operator, eg a cross cutter, is to drive in the machining or cutting area as precisely as possible linearly or as accurately as possible according to a predeterminable profile (so-called pushout function or so-called cos β correction) in order to achieve the cut with optimum accuracy perform. Modern drive systems offer the possibility the following error, ie to measure the angular error between the target position and actual position of the cross-processing roller. This following error can now be monitored according to the invention. Optionally, a message may be issued, or the machine speed may be adjusted to ensure that a predetermined limit is not exceeded.

This measure allows a monitoring of a required accuracy or optimization of the maximum speed by allowing a deviation. Furthermore, a targeted optimization of correction movements is possible. The accuracy monitoring according to the invention enables better overall cut edges, cleaner cuts and an overall higher quality of the cut fabric web sections.

figure description

Figur 1

eine schematische Darstellung wesentlicher Komponenten einer Querschneidervorrichtung, bei der die Erfindung vorteilhaft einsetzbar ist,

Figur 2

Schnittkurven einer typischen Querbearbeitungswalzenanwendung gemäß dem Stand der Technik,

Figur 3

Schnittkurven einer erfindungsgemäßen Querschneideranwendung, und

Figuren 4a, 4b, 4c

weitere erfindungsgemäße verwendbare Schnittlinien für einen Querschneider.

The invention will now be further described with reference to the following drawings. In this shows or show

FIG. 1

a schematic representation of essential components of a cross-cutting device, in which the invention is advantageously used,

FIG. 2

Sectional curves of a typical cross-roller application according to the prior art,

FIG. 3

Section curves of a cross cutter application according to the invention, and

FIGS. 4a, 4b, 4c

further usable cutting lines according to the invention for a cross cutter.

In FIG. 1 a cross-cutting device is shown schematically and designated 100 in total. Such a cross-cutting device is a preferred example of the cross-processing device according to the invention.

The cross-cutting device has a cross-processing roller 110 and a counter-pressure roller 120 cooperating therewith.

The cross-processing roller 110 and optionally also the counter-pressure roller 120 can be driven by means of a drive 140.

The drive is controlled by means of a control device 150, which in particular comprises an HMI 155.

Between the cross-processing roller 110 and the counter-pressure roller 120, a material web 130 is transported in the transport direction T.

By means provided on the transverse processing roller 110 cutting device 115, which is designed in particular as a cutting knife, there is a separation of the material web 130 into respective sections. When the length of the cut-away web portions corresponds to the circumferential length of the cross-processing roll 110 (2πr), it is called the synchronous length. The synchronous length is in FIG. 1 denoted by f.

Depending on the desired format length takes place with respect to the transport speed of the web 130 in the transport direction T faster or slower movement of the cross-processing roller 110, ie a faster or slower rotation its axis of rotation A. These movements are controlled by means of the control device 150, wherein corresponding control commands are given to the drive 140. Control commands can be introduced in particular via the HMI 155 in the control device. Furthermore, an automatic selection or calculation of laws of motion by means of the control device 150 is possible by entering appropriate format specifications by means of the HMI.

Typical movements, such as those according to the invention with a cross-cutting device, as shown in FIG. 1 are illustrated, executable, are now with reference to the FIGS. 2 to 4 described.

FIG. 2 11, above, shows sectional curves for a compensating movement of the cross-processing roller 110 at which the format length should be shorter than the synchronous length. Individual graphs are shown for the (angular) position of the roller (α), its speed (v) and its acceleration (a). Essential in the present case is the speed v. A cutting region, ie region in which the cut of the material web takes place by means of the cutting blade 115, is denoted by s. It can be seen that the compensation movement is carried out at a higher speed than the speed in the cutting area. That is, as long as the cutting blade 115 is not in the cutting area, the rotation of the cross-processing roll 110 is at a higher speed relative to the rotation in the cutting area. The position α as well as the acceleration a of the cross-processing roller result directly from the selected speed.

In FIG. 2 is the corresponding situation for a format length, which should be longer than the synchronous length represented. It can be seen that the compensation movement (outside of the cutting area) at a lower speed than the speed in the cutting area. However, the speed also always has a positive sign here.

The FIG. 2 shows essentially sectional curves according to the prior art.

In FIG. 3 corresponding sectional curves are shown according to the present invention, which also allow a backward movement.

According to the invention, the backward movement or rotation of the cross-processing roller 110 is limited to a certain angle. In FIG. 3 At the top, one can see two boundary lines 310, 320, by means of which it is shown that here the rearward movement of the cross-processing roller 110 is limited to 20 degrees. The corresponding speed v of the transverse processing roller 110 is correspondingly smaller than zero over a certain range b.

In FIG. 3 the corresponding situation is shown for a compensation movement with a limitation to a backward movement of 120 degrees. The negative velocity v is accordingly maintained over a longer range b '.

In FIG. 4 Finally, different laws of motion are shown, which can be used depending on the format or depending on specific specifications.

In FIG. 4a a compensation movement is represented by means of a law of motion according to a 5th degree polynomial.

FIG. 4b shows corresponding compensatory movements on the basis of a polynomial 3rd degree, which can be used for energy optimization.

Figure 4c shows corresponding compensatory movements based on a modified sine curve.

The three upper diagrams show angular position α, velocity v and acceleration a. The lower diagram shows the square of the acceleration a ² . This is the basis for a loss energy consideration.

With the method according to the invention and due to specific specifications of a user, for example with respect to the desired format length and / or allowable reverse rotation of the cross-processing roller, it is possible in a flexible manner to calculate the optimum compensation movement for the respective specifications on the basis of different laws of motion. If, for example, it is specified that a reverse rotation should not exceed 20 degrees or another predefinable angle, the system calculates the optimum compensation movement on the basis of a large number of possible laws of motion.

reference numeral

100

Transverse cutter device

110

Transverse machining roller

115

cutter

120

Backing roll

130

web

140

Drive (motor)

150

control

155

HMI

A, 310, 320

boundary lines

A

Axial cross machine roller

f

synchronous length

r

Radius cross-machine roller

T

transport direction

α

Angular position Cross-processing roller

v

Speed cross-machine roller

a

Acceleration cross roller

s

cutting area

b, b '

Areas of negative speed

Claims (9)

Method for operating a cross-processing roller of a cross-drive device driven by a drive for rotationally severing a transportable web in a transport direction to provide processed web sections of different formats, comprising the following steps: Choosing a desired format for web sections, Provision of a number of laws of motion for controlling a rotary movement of the cross-processing roller in a control device, for the desired format, providing or calculating a movement of the cross-processing roller on the basis of the laws of motion provided in the control device and / or at least one parameter of the drive and / or at least one default of a user. A method according to claim 1 for operating a cross cutter roll, a cross seal roll, a transverse perforation roll or a cross bar roll of a cross cutter device, a transverse sealing device, a transverse perforating device or a transverse punching device. Method according to claim 1 or 2, wherein the parameters of the drive comprise at least one element from the group, comprising: maximum drive or engine torque, maximum drive or engine temperature, maximum drive or motor speed, estimated occurring machining forces, in particular cutting forces, mechanical conditions, such as moments of inertia or mechanical translations. Method according to one of claims 1 to 3, wherein by means of a law of motion, a compensating movement of the cross-processing roller, which in particular a maximum allowable reverse rotation of the cross-processing roller opposite to the transport direction, is calculated. The method of claim 4, wherein the maximum allowable reverse rotation of the cross-processing roller is limited by means of a predetermined angle. Method according to one of the preceding claims, characterized by monitoring the machining accuracy in the processing region of the transverse processing roller. Cross-processing device with means for carrying out the method according to one of the preceding claims. Computer program with program code means for performing all the steps of a method according to one of claims 1 to 6, when the computer program is executed on a computer or a corresponding computing unit, in particular in a cross-processing apparatus according to claim 7. A computer program product comprising program code means stored on a computer-readable medium for carrying out all steps of a method according to one of claims 1 to perform 6, when the computer program on a computer or a corresponding processing unit, in particular in a cross-processing device according to claim 7 is executed.

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