EP1958905A2 - Method and device for friction compensation - Google Patents

Abstract

The friction compensation device is fitted to a winding machine (1) by which material (70) is wound onto a winding drum (30) controlled by a controlling and regulating device (10). It has an additional process parameter (80) engaged on the input side for compensation of the friction moment in the friction compensation unit (14).

Description

State of the art

The invention relates to a method for friction compensation in a winding machine, with which a material is wound onto a winding drum, wherein the winding drum is driven by a winding drive, which is driven by a control / regulating device, wherein in the control / regulating a drive torque of Winding drive is specified, wherein in a Reibkompensationseinheit as an input-side process parameters, an angular velocity of the winding drum is taken into account.

The invention further relates to a device for friction compensation in a winding machine, with which a material is wound on a winding drum, wherein the winding drum is driven by a winding drive, which is controllable with a control / regulating device, wherein in the control / regulating device a tension regulator and a diameter-calculating unit and / or a Reibkompensationseinheit for linearization of the tension controller are arranged, wherein in the friction compensation unit as an input-side process parameter, an angular velocity of the winding drum is switched on.

Winding machines for winding sheet-like materials, such as fibers, paper, films, fabrics, thin sheets, etc., or wire-like or yarn-like materials are well known in the literature. Characteristic of such machines is an exact control of the tension during the winding process to avoid uneven or faulty winding results. A number of documents are therefore concerned with the engine control for the drives in such machines.

In the DE OS 3919162 A1 For example, a control device for a winding machine is described, with which the tension is regulated at a running from a feed roller to a take-up spindle product. The controller includes a high speed response ratio control unit for accurately controlling the respective rotational speeds of a feed motor for driving the feed roller and a winding motor for driving the takeup spindle during deceleration of the winding machine. This can be achieved that the product is kept under tension, which is substantially equal to a predetermined tension for the steady operation. With the control device required for stopping the winding machine time is reduced to the minimum.

From the DE OS 10342020 A1 is a winding machine for winding a material web, in particular a fibrous web, with a against a Tambour (winding roller) squeeze Luftabquetschwalze known in which the speed and / or torque of Luftabquetschwalze is dependent on a current web tension of the web.

Winding machines are usually realized with torque or current-limited speed control. The value for the limitation of the torque or the current is composed of several components. These are the moment component for the tensile stress, the moment component for the acceleration and the friction torque.

The control / regulating devices of the winding machines, which are also referred to as winding computer, therefore, also consist of several functional elements that calculate the various instantaneous portions of the drive and drive according to the winding drive.

In addition to a tension controller, which is the main component for the actual control loop, today's winding calculator usually still have a diameter computing unit, possibly an acceleration compensation unit and a Reibkompensationseinheit, which serve to linearize the controlled system for the actual tension controller of the winding computer to a to carry out as far as possible interference-independent control. The individual components in the winding computer are loaded on the input side with different process parameters, which are partially detected by corresponding sensors in the winding machine or calculated by means of models.

With regard to friction compensation, only relatively simple models are considered in the prior art. It is currently customary for the speed of the winding axis or the angular velocity to be used as the process parameter only to determine a friction compensation value. In addition, there are often no tools to adjust the required parameter values of the compensation. So far, only systems are known in which a characteristic curve, formed from rotational speed of the winding axis and friction torque, can be set with few support points. Such a system is known, for example, in connection with the control devices for winding machines of the type REXROTH SYNAX 200, in which a friction torque at standstill, a minimum friction torque at a certain speed and a maximum friction torque at a speed limit in the form of support points for a simple Characteristic is specified.

The disadvantage here is that significant friction effects in the scheme can not be considered. For example, depending on the mass of the coil, the bearing friction or the transmission losses vary in size. The contact pressure of an optional pressure roller is not taken into account in today Reibabensationseinheiten. Further non-constant frictional effects result, for example, from a position-dependent friction, as may occur in certain transmission configurations, as well as from a temperature-dependent friction.

All these disregarded friction components mean that the controlled system does not become linear. As a result, you will not be able to optimally set the control algorithm or the effort in setting or testing the set parameters will be quite high. In addition, the disturbance behavior of the entire system is limited by this.

It is therefore an object of the invention to provide a method which makes possible an improved consideration of the friction components in winding processes as well as an improved determination of the compensation parameters. It is a further object of the invention to provide a corresponding device ready.

Advantages of the invention

The object relating to the method is achieved by taking into account at least one additional process parameter to compensate for the frictional torque. As a result, the different Reibkompensationsanteile better taken into account in the specification of the drive torque, resulting in a much improved control results.

If it is adjusted by means of a tension controller a Zugsollkraft with a measured Zugistkraft, deviations from the specification can be detected directly and the drive torque can be adjusted.

If a position of the tensile force by means of a control part, can be dispensed with in this case to a measuring device for the Zugspannungsistwert, which allows a simplified structure, which is correspondingly less expensive.

In a preferred embodiment, it is provided that in the control / regulating device with a diameter-calculating unit and / or the Reibkompensationseinheit the drive torque of the winding drive is specified. Thus, a more accurate specification of the drive torque can be calculated.

A further preferred variant of the method provides that the drive torque of the winding drive is predetermined in the control / regulating device with an acceleration compensation unit. This allows additional dynamic effects to be taken into account when specifying the drive torque.

If a winding mass and / or a temperature and / or a roll contact pressure and / or a winding angle actual value are used as additional input-side process parameters to compensate for the frictional torque, both winding mass-dependent friction, contact-pressure-dependent friction, position-dependent friction and temperature-dependent friction effects can be taken into account. Depending on the mass of the coil, e.g. the bearing friction or the transmission losses differently. Furthermore, a different drive torque may be required by the contact pressure of an optional pressure roller. Position-dependent friction can occur, for example, due to intermeshing gears, in which the friction over the circumference is not constant. This is particularly the case with a coarse pinion pitch (i.e., low number of gear teeth). This friction can occur on the motor side, on the load side (winding) or else somewhere within a gearbox between the motor and the load. Temperature-dependent friction can occur, for example when using timing belt as a translation link between the engine and the winding. At higher load, in particular, the friction of this belt is temperature-dependent, since this is heated, which in turn can result in a change in friction. Warming usually causes elongation of the toothed belt, which can then result in less friction, as the toothed belt tension decreases during elongation. These effects can now be considered much better with the method according to the invention.

A variant of the method according to the invention provides that the individual process parameters used to compensate for the frictional torque are evaluated independently of one another and additively linked to a total friction compensation. This has the advantage that in addition to today's speed-dependent Reibkompensationswert additional Reibkompensationswerte, such as a winding mass-dependent Friction compensation value are added and these can be treated independently of each other, which offers advantages in terms of a simplified algorithm advantages.

However, a variant of the method also provides that at least two of the individual process parameters used to compensate for the frictional torque are linked to one another and from this a compensation value is determined. This is particularly advantageous in terms of complex, interdependent relationships for determining the friction compensation.

It is particularly advantageous if the compensation parameters for the individual process parameters for the determination of the compensation value in the form of one or more characteristic fields or maps are processed and the compensation value for the friction torque is determined directly or by interpolation between nodes from the maps. This makes it possible to consider particularly complicated relationships that can not easily be represented by means of functions.

A further variant of the method according to the invention provides that the compensation parameters for the individual process parameters are determined and stored with defined conditions before or during a winding-up operation in a plurality of measuring runs. This allows automated as well as manual detection of the inputs required to determine the friction compensation values. This eliminates the need for complicated input, which minimizes programming effort and helps to reduce possible incorrect entries. In addition, the system can be adapted very quickly to different web materials on different winding rollers.

A likewise preferred variant of the method provides that the compensation parameters for the individual process parameters are used for maintenance purposes and / or messages are generated in the event of deviations and / or temporal changes compared to standard values. Thus, any defects can be reliably detected and displayed, which supports preventive maintenance or only possible.

In the method described above it can be provided that the process parameter winding mass is determined as a function of a winding diameter or radius, a winding width and a density of the material or diameter-dependent variable density of the winding from a diameter-dependent web tension or a winding hardness characteristic. This allows an independent determination of the winding mass-dependent compensation, even without consideration of the acceleration compensation, in which the mass of the coil is known and carried in the process.

Furthermore, it can be provided that the process parameter temperature is determined by measuring the temperature at the winding drive or by calculation by means of a thermal model. Temperature-dependent friction components can thus be accurately determined and compensated accordingly.

A variant of the method provides that the process parameter Walzenanpressdruck is measured or calculated from other process parameters. This is particularly advantageous when using a pressure roller.

In order to compensate for winding layer-dependent components, it may be provided that the compensation parameters which depend on the process parameter motor or winding angle actual value are in the form of a database within the friction compensation unit or the control device, e.g. as a table.

The object relating to the device is achieved in that at least one additional process parameter is connected on the input side to compensate for the frictional torque in the friction compensation unit. This makes it possible, in particular, to use the method variants described above with regard to improved consideration of a wide variety of friction compensation components.

In one embodiment, an acceleration compensation unit is arranged in the control / regulating device, which allows an improved control, especially at constantly changing web speeds.

The preferred embodiment provides that the friction compensation unit has as additional input variables a winding mass and / or a temperature and / or a roll contact pressure and / or a motor or Wickelwinkelistwert, thereby winding mass-dependent, temperature-dependent, possibly Anpresswalzenabhängige and / or winding ply dependent proportions in the Specification of the drive torque can be considered.

For a simple determination of the friction compensation values, the friction compensation unit can have at least one map unit for linking at least two process parameters.

In a particularly preferred embodiment, compensation parameters for individual friction components can be determined in the friction compensation unit and / or in the control / regulating device and can be stored for further evaluations. On the one hand, this allows flexible adaptation to different operating conditions and, on the other hand, preventive maintenance and inspection of the mechanism.

drawings

• Figur 1 in schematischer Darstellung eine Wickelmaschine mit einer Steuer-/Regeleinrichtung nach dem Stand der Technik,
• Figur 2 schematisch eine Wickelmaschine mit einer Steuer-/Regeleinrichtung in erfinderischer Ausgestaltung.

The invention will be explained in more detail below with reference to the exemplary embodiments illustrated in the figures. Show it:

• FIG. 1 a schematic representation of a winding machine with a control device according to the prior art,
• FIG. 2 schematically a winding machine with a control / regulating device in an inventive design.

Description of the embodiments

FIG. 1 shows by way of example in schematic representation a winding machine 1, which contains as essential components a winding drum 30 which is driven by means of a winding drive 20. A material 70, for example, a web-shaped product to be wound, is formed in the example shown first via a first deflection 61, here as a fixed roller, and then via a second deflecting 62, which is formed as a loose roll, and then over a led third deflection device 63 in the form of another fixed roller and finally reaches the winding drum 30, wherein in the example shown, a pressure roller 40, the material 70 presses on the already formed winding on the winding drum 30, for example, to avoid trapped air.

The deflection device 62 is in mechanical operative connection with a force measuring device 50. The force measuring device 50, which is connected on one side fixed to the structure of the winding machine 1, for example, be designed as a load cell, with which the tension of the material 70 can be determined during the winding. The measured values are fed to a control / regulating device 10 (winding computer) (not shown here) and serve in particular as an input variable for a tension regulator 11 integrated in the control / regulating device 10, which controls the winding drive 20. Alternatively, only one position of the tensile force can take place.

According to the prior art, the control / regulating device 10 also contains further functional elements, such as a diameter calculating unit 12, an acceleration compensation unit 13 and a friction compensation unit 14, which serve to linearize the controlled system for the tension controller 11, as far as possible independent of disturbance regulation to carry out. This leads to a better control quality of the overall system. In this case, as shown, a manipulated variable as an output signal 'of the tension controller 11 with correction manipulated variables as output signals of the diameter-calculating unit 12 and the acceleration compensation unit 13 in a first link 15 combined into a manipulated variable. In the example shown below is then in a second link 16 is supplied to the control signal for the winding drive 20 yet another correction manipulated variable as an output signal of the friction compensation unit 14. Usually, the friction and the acceleration compensation are switched on as a feedforward control of the drive torque. The algorithms of the individual components in the control / regulating device 10 are fed by different process variables and control the winding drive 20.

According to the prior art, it is provided that only the value for an angular speed 81 of the winding drum 30 is supplied to the friction compensation unit 14 as the process parameter 80. The value for a compensation value for the friction torque is usually calculated from the angular speed 81 in a relatively simple model.

FIG. 2 shows a schematic representation of a winding machine 1 in an inventive embodiment, in contrast to the in FIG. 1 illustrated embodiment, a control / regulating device 10, in which the friction compensation unit 14 on the input side has additional process parameters 80.

In addition to the angular velocity 81 of the winding drum 30, the friction compensation unit 14 in the example shown as an additional input value for a winding mass 82, a value for a temperature 83 of the winding drive 20, a value for a roll contact pressure 84 and a value for a motor or Winding angle actual value 85 supplied. Like in the FIG. 2 indicated, yet other input variables of the friction compensation unit 14 can be switched.

In one embodiment, it may be provided that the compensation values for the individual friction components are activated additively independently of one another. For example, in addition to the speed-dependent Reibkompensationswert still a path with a winding mass-dependent Reibkompensationswert is added up. The two paths are independent of each other, ie the speed-dependent friction compensation is winding mass independently switched on and the winding mass-dependent friction compensation is switched independent of speed.

In another embodiment, it is provided that the total friction compensation is formed additively from mutually dependent compensation components. At least two of the dependent variables are linked with each other and the compensation value is determined therefrom. This results in the model characteristic curves or maps, which can be represented in the case of two interdependent sizes as area in space. Thus, for example, the compensation values for the friction can be determined from a characteristic field which is spanned from the winding mass 82 and the angular speed 81 of the winding drum 30. As a further dimension of the map, the temperature 83, the Walzenabpressdruck 84 and the motor or Wickelwinkelistwert 85 can be used. The characteristic curves do not have to be completely known. The compensation values can be determined, for example, by appropriate interpolations (for example, linear interpolation) from the characteristic field, even if only a few interpolation points are known.

The device in FIG. 2 Therefore, in the friction compensation unit 14 or the control / regulating device 10 according to the invention has at least one map unit 14.1, which is stored for example in software in the control program.

Furthermore, the various friction components can be determined from several characteristic fields and then additively linked. A combination of the previously described evaluation methods is also possible.

It can be provided that the process parameter winding mass 82 is determined as a function of a winding diameter or radius, a winding width and a density of the material or diameter-dependent variable density of the winding from a diameter-dependent web tension or a winding hardness characteristic. Since the winding width and the material density in the process are normally constant, the winding mass 82 results only as a function of the diameter or the radius. But it can also be the material density in the Process vary because due to a given diameter-dependent web tension (winding hardness characteristic), the average density of the coil can change. This too can be determined since the web tension or the winding hardness characteristic is usually known.

Furthermore, it can be provided that the process parameter temperature 83 is determined by measuring the temperature at the winding drive or by calculation by means of a thermal model. Temperature-dependent friction components can thus be accurately determined and compensated accordingly.

A variant of the method provides that the process parameter roller contact pressure 84 is measured or calculated from further process parameters. This is particularly advantageous when using a pressure roller. The corresponding compensation component can be calculated as a function of the contact pressure and possibly other process variables (for example, winding diameter), this being proportional to the product of contact pressure and winding diameter to a first approximation.

In order to compensate for winding layer-dependent components, it is provided that the compensation parameters, which are dependent on the process parameter motor or winding angle actual value 85, are stored in the form of a database within the friction compensation unit or the control device, e.g. as a table. In addition, one or more gear stages between the motor and winding drum 30 can be considered.

With regard to the determination of the compensation parameters, which with increasing complexity plays an important role in addition to the pure compensation, it is provided, for example, procedurally to carry out automated test runs.

With the test drives, the characteristic field can be determined and stored in the control, wherein, for example, the winding mass-dependent friction compensation by means of several test drives, eg with an empty winding, are carried out at full winding and half full winding. Each test run can include several speed measuring points, where the compensation torque is determined, eg by means of the in Winding drive 20 existing drive torque, wherein the traction-forming drive torque must be subtracted from the total drive torque to determine the friction compensation.

Likewise, measuring runs can be carried out to determine the parameters of the temperature-dependent compensation, the compensation of the contact roller pressure and the position-dependent compensation.

The test drives can also be used for preventative maintenance. For this purpose, measuring runs with an empty roll are advantageous, since here the properties of the winding material can be neglected. For example, a limit for the Anfahrreibmoment (breakaway torque) or for the maximum occurring friction torque, which usually occurs at high speeds are given, from which a message is generated. This could e.g. used to service or replace bearings.

Furthermore, the test drives can also be used as a reference measurement for checking the mechanics. After replacement of mechanical components, e.g. after a timing belt change, these can also be checked for correct adjustment (such as timing belt tension) or correct function by means of these measuring runs. For example, if the timing belt tension is very high, the drive torque will also increase sharply.

The illustrated variants of the method and the device variants described make it possible to take better account of the various friction compensation components in the control of the winding drive 20, resulting in a significantly improved control. Furthermore, the various compensation parameters can largely be determined and monitored automatically. The latter can be used advantageously with regard to the maintenance and monitoring of winding machines 1.

Claims (20)

Method for friction compensation in a winding machine (1), with which a material (70) is wound onto a winding drum (30), wherein the winding drum (30) is driven by a winding drive (20) which is controlled by a control device (10 ), wherein in the control / regulating device (10) a drive torque of the winding drive (20) is specified, wherein in a Reibkompensationseinheit (14) as an input-side process parameters (80) an angular velocity (81) of the winding drum (30) is taken into account , characterized in that at least one additional process parameter (80) is taken into account for the compensation of the friction torque. A method according to claim 1, characterized in that by means of a tension controller (11) is adjusted a Zugsollkraft with a measured Zugistkraft. A method according to claim 1, characterized in that a position of the tensile force is effected by means of a control part. Method according to one of claims 1 to 3, characterized in that in the control / regulating device (10) with a diameter-calculating unit (12) and / or the Reibkompensationseinheit (14), the drive torque of the winding drive (20) is specified. Method according to one of claims 1 to 4, characterized in that in the control / regulating device (10) with an acceleration compensation unit (13), the drive torque of the winding drive (20) is specified. Method according to one of claims 1 to 5, characterized in that to compensate for the friction torque, a winding mass (82) and / or a temperature (83) and / or a roll contact pressure (84) and / or a motor or winding angle actual value (85). be used as additional input-side process parameters (80). Method according to one of Claims 1 or 6, characterized in that the individual process parameters (80, 81, 82, 83, 84, 85) used for compensation of the frictional torque are evaluated independently of one another and are additively linked to a total friction compensation. Method according to one of Claims 1 to 6, characterized in that at least two of the individual process parameters (80, 81, 82, 83, 84, 85) used for compensation of the frictional torque are linked together and from this a compensation value is determined. A method according to claim 8, characterized in that compensation parameters for the individual process parameters (80, 81, 82, 83, 84, 85) for determining the compensation value in the form of one or more characteristic fields or maps are processed and the compensation value for the friction torque directly or is determined by interpolation between nodes from the maps. Method according to one of claims 1 to 9, characterized in that the compensation parameters for the individual process parameters (80, 81, 82, 83, 84, 85) are determined and stored before or during a winding in several test drives with defined conditions. Method according to one of claims 1 to 10, characterized in that the compensation parameters for the individual process parameters (80, 81, 82, 83, 84, 85) be used for maintenance purposes and / or messages are generated in case of deviations and / or temporal changes compared to standard values. Method according to one of claims 6 to 11, characterized in that the process parameter winding mass (82) as a function of a winding diameter or radius, a winding width and a density of the material (70) or diameter - dependent variable density of the winding from a diameter - dependent web tension or A winding hardness characteristic is determined. Method according to one of claims 6 to 11, characterized in that the process parameter temperature (83) by measuring the temperature at the winding drive (20) or by calculation by means of a thermal model is determined. Method according to one of claims 6 to 11, characterized in that the process parameter Walzenanpressdruck (84) is measured or calculated from further process parameters (80). Method according to one of claims 6 to 11, characterized in that the compensation parameters, which are dependent on the process parameter motor or winding angle actual value (85), stored in the form of a database within the Reibkompensationseinheit (14) or the control / regulating device (10) become. Apparatus for friction compensation in a winding machine (1), with which a material (70) can be wound on a winding drum (30), wherein the winding drum (30) is driven by a winding drive (20) which is connected to a control / regulating device (10 ) is controllable, wherein in the control / regulating device (10) has a tension controller (11) and a diameter-calculating unit (12) and / or a Reibkompensationseinheit (14) for linearization of Zugspannungsreglers (11) are arranged, wherein in the Reibkompensationseinheit (14) as an input-side process parameter (80) an angular velocity (81) of the winding drum (30) is switched, characterized in that for compensating the friction torque in the Reibkompensationseinheit (14) at least one additional process parameter (80) is connected on the input side. Apparatus according to claim 16, characterized in that in the control / regulating device (10) an acceleration compensation unit (13) is arranged. Apparatus according to claim 16 or 17, characterized in that the friction compensation unit (14) as additional input variables a winding mass (82) and / or a temperature (83) and / or a roll contact pressure (84) and / or a motor or winding angle actual value ( 85). Device according to one of claims 16 to 18, characterized in that the friction compensation unit (14) has at least one map unit (14.1) for linking at least two process parameters (80). Device according to one of claims 16 to 19, characterized in that in the friction compensation unit (14) and / or in the control / regulating device (10) compensation parameters for individual friction components can be determined and stored for further evaluations.

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