EP1726547A1 - Reel winding device - Google Patents

Abstract

Roller winding device comprises roller bearings (6, 7) connected to a support (10) via a damping part (11, 12) which has a cylinder (16) containing a plunger (17) which divides the cylinder into two pressure chambers (18, 19). The plunger is connected to the roller bearings and the cylinder is connected to a support. Both pressure chambers are connected to a connecting segment which contains throttles. Preferred Features: A switching valve is arranged in the connecting segment to interrupt the connecting segment. The plunger has large pressure working surfaces in both pressure chambers.

Description

The invention relates to a reel winding device with at least one roller on which a Wikkelrolle rests during winding and which is mounted in a roller bearing.

The invention will be described below with reference to a Rollenwikkeleinrichtung which winds a web to a winding roll. However, it is not limited to this application.

A paper web is produced in a relatively large width of currently up to 12 m and virtually endless. In order to be usable for a later consumer, the paper web must be divided into narrower webs. These narrower webs must then be wound up into rolls. For this purpose, a roll winding device is used.

In some reel winders, also referred to as "slitter winder", problems due to high vibration occur in operation, the consequence poor winding, heavy use of the machine and the foundations, reduction of production speed or roller swings to the role ejection are. When reel winders were looking for imbalances in rollers or reels, after vibrations in the drive and control system and similar changes that are usually associated with much effort, the difficulties have not been able to completely resolve.

Occurring vibrations with concomitant out of roundness of the winding roll may be associated with the processing of certain types of paper. For example, the friction behavior or the paper thickness represent relevant quantities.

It is believed that contact vibration between the winding roll and the roll or rollers is the cause of the out-of-roundness of the winding roll, the roll or rolls and the winding roll or parts thereof, e.g. the outer shell of a limited number of paper layers, swing against each other. This can lead to a non-uniform structure of the winding roll (density, stiffness, thickness variation, air pockets, shifting paper layers), which in turn can increase the contact vibrations.

At the end of the winding process, the bobbins are decelerated to a standstill. If the rotational frequency of the winding roll passes through the natural frequency of the oscillation of the entire system, then a roll swings can occur. The winding roll vibrates, which can lead to a role ejection.

Vibrations occurring during the winding process are classified into two problem areas, namely roll hum and roll swings.

The roller humming is a contact vibration between the winding roller and the roller or the rollers, wherein when using several rollers, in which the Wikkelrolle is applied, the rollers can oscillate against each other. Roller rumbling may occur when a harmonic of the rotational frequency of the winding roll or winding rolls (when several winding rolls are wound simultaneously) is in the range of the natural frequency of the contact vibration.

Due to the roll humming it can lead to a non-uniform structure of the paper in the winding roll, which in turn can increase the contact vibrations.

The invention has for its object to avoid critical conditions when winding.

This object is achieved with a roller winding device of the type mentioned above in that the roller bearing is connected via an attenuator with a support having a cylinder and a piston arranged therein, which divides the cylinder into two pressure chambers, wherein the piston with the roller bearing and the cylinder in contact with the support is and the two pressure chambers via a connecting path, which contains at least one throttle, are connected.

With such an attenuator, it is possible to initiate speed-proportional damping forces to the roller in a significant bearing movement, as occurs in a vibration state of the roller. This hydraulic fluid is pumped back and forth between the two pressure chambers. This liquid must flow through the throttle. In this case, the liquid is deprived of energy, so that the vibration is damped. The damping is greater, the stronger the vibration, so an effect that is desired. Of course, such a design can be realized even if the cylinder is connected to the roller bearing and the piston with the support at the attenuator.

Preferably, the permeability of the connection path is variable. So you can change the damping behavior of the attenuator in operation, if necessary. In other words, by adjusting the permeability of the connecting section, the roller bearing can be made "soft" or "hard". As the permeability of the link changes, the natural frequency of the system of roller, bearing and support changes. By changing the natural frequency, critical vibration states can be eliminated.

Advantageously, a switching valve is arranged in the connecting path, with which the connection path can be interrupted. The switching valve, when actuated, can block the flow of hydraulic fluid from one pressure chamber to the other through the communication path. Thus, the piston is clamped between the two pressure chambers, so that there is a "hard" storage of the roller. Should it therefore come in the damped operation in which the piston hydraulic fluid between the two pressure chambers back and forth, so the basic mode of operation, the reel winding to self-excited vibrations, then the bearing stiffness of the roller by interrupting the link between the two cylinder chambers very much be changed quickly. By shutting off the connection path, the damping effect of the attenuator is switched off and the hydraulic fluid, for example hydraulic oil, clamped in the pressure chambers acts like a rigid support roller bearing. As a result, the natural frequency of the system of roller and winding roller and thus also the feedback mechanism of wavy winding rollers on the roller changed.

Preferably, the piston has equally large pressure application surfaces in both pressure chambers. Thus, in a reciprocating motion always the same volume of oil is promoted in both directions of movement. It does not change the volume necessary to hold the oil. An external memory is unnecessary. The same size pressure application surfaces can be characterized for example produce that one provides the piston not only on one side, but on both sides with a piston rod and leaves the piston rod not connected to the roller bearing unused, for example, leads to a blind bore in the cylinder, which is sealed.

Preferably, the two pressure chambers are connected to a circulation flow generating device. By means of the circulation flow generating device, a permanent flow of hydraulic fluid through the two pressure chambers can be generated, at least if the connection path is still permeable or if each pressure chamber is separately connected to the circulation flow generating device. This can be achieved over time constant damping properties. The circulation volume flow does not have to be large. He only has to suffice to dissipate the generated heat of friction, so the damping energy.

It is advantageous if the circulation flow generating device has a tempering device. The flow resistance to which the hydraulic fluid is exposed depends, inter alia, on the viscosity and thus on the temperature of the hydraulic fluid. If you always allows the temperature of the hydraulic fluid to a largely constant value, then you always have constant or similar damping properties in operation, regardless of whether the reel winder running only briefly or has been in operation for some time.

Preferably, the two pressure chambers are additionally connected to each other by a pressure equalizing throttle. Such a pressure equalizing throttle avoids a jerk of the roller, for example, when switching back from the locked state of the link back to the muted operating mode in which the link is permeable in the context of throttling by the throttle. The pressure compensation throttle allows a static pressure equalization, which may be necessary, for example, due to the growing weight of the winding roll.

Preferably, the pressure compensating throttle is arranged in the piston. The pressure compensating throttle can be kept very small, so that no additional space is required outside of the attenuator. Leaks that may occur when connecting the pressure compensation throttle can be reliably avoided.

It is also advantageous if the pressure compensation throttle has a much greater throttle resistance than the throttle. This can be achieved, for example, by introducing a very narrow bore in the piston. The bore then has such a small diameter that the "short-term" moving oil volume (usually in the frequency range of 30-40 Hz) in the pressure chambers seen dynamically acts as firmly clamped. The design can then be designed so that the acceleration forces acting on the hydraulic fluid, which are necessary for the passage of the connection, are substantially greater than the frictional forces, which occur when flowing through the pressure compensation throttle.

Preferably, the roller bearing is connected via a spring with the support. Such a spring seems at first absurd because it promotes the tendency of the roller to vibrate. But since the attenuator is present, you can reliably prevent the swinging of the roller in certain frequency ranges by a combination of attenuator and spring.

It is preferred that the spring is formed by a spring rocker. Such a spring is relatively stiff. It is practically integrally connected to a machine frame, so that here basically no further maintenance is necessary.

Alternatively, the roller bearing may also be mounted on an articulated arm, which is supported by a spring element on the support. In this case, the same effect results.

It is also advantageous if two rollers are provided with roller bearings, which are each connected via an attenuator with the support, wherein a control device is provided, the vibration-dependent changes the permeability of the connecting path of one attenuator, the other attenuator or both attenuators. In other words, you can the bearing stiffness of a roller or both rolls change if necessary to combat natural vibration.

Fig. 1

eine schematische Darstellung einer Rollenwickeleinrichtung und

Fig. 2

eine schematische Darstellung eines Dämpfungsglieds.

The invention will be described below with reference to a preferred embodiment in conjunction with a drawing. Herein show:

Fig. 1

a schematic representation of a roll winding device and

Fig. 2

a schematic representation of an attenuator.

Figure 1 shows a roll winding device 1, which is designed in the present embodiment as a support roll winding device. The roll winding device 1 accordingly has two support rollers 2, 3, which form between them a winding bed 4, in which a winding roller 5 is arranged. The winding roll 5 is shown here with diameters of different sizes in order to make the progress, ie the diameter increase, visible during winding.

Not shown is a material web which is wound on Wikkelrolle 5, or a supply station, from which the material web is withdrawn. These elements are known in a roll winding device per se.

Notwithstanding the embodiment of Figure 1, the idea explained below can also be used in a so-called support or contact roller winding device be, in which the winding roller 5 is present in each case only on a roller, but otherwise is kept centric.

In the roll winding device shown in FIG. 1, a plurality of winding rolls 5 can be arranged axially one behind the other in the winding bed 4 in the axial direction of the two support rolls 2, 3. In a support or contact roller winder, the individual winding rollers 5 are expediently then distributed on both sides of the corresponding roller.

Usually, such a reel winding device 1 is also provided with a longitudinal cutting device which divides the tapered material web into a plurality of mutually parallel partial webs. The partial webs may have a width in the range of about 0.3 to 4.8 m.

Further details of a roll winding device, such as a back-up roll, which is also referred to as a rider or load roller, or drive motors for the support rollers 2, 3 are not shown here.

The two support rollers 2, 3 are rotatably mounted in roller bearings 6, 7. Of course, a corresponding arrangement is provided with roller bearings at the other axial end of the two support rollers 2, 3.

The roller bearing 6 is mounted on a spring rocker 8 and the roller bearing 7 is mounted on a spring rocker 9.

The two spring wings 8, 9 are connected to a machine frame 10. They form relatively stiff springs on which the roller bearings 6, 7 are supported.

Instead of the spring rocker shown in Fig. 1, which can also be referred to as a "bending arm" and which is integrated into the frame or the machine frame 10, one can also use in a different embodiment, an articulated arm which is hinged to the machine frame 10, wherein the articulated arm is then supported on the machine frame 10 via a spring, for example a helical spring.

Between the spring rocker 8, 9 and the machine frame 10, an attenuator 11, 12 is arranged in each case. Both attenuators 11, 12 are connected to a control device 13. The control device 13 in turn connected to vibration sensors 14, 15, each detecting a vibration of the roller bearing 6 and 7 respectively.

The operation of the control device 13 will be explained in more detail after the explanation of a single attenuator 11 with reference to FIG. 2. The other attenuator 12 is constructed accordingly.

The attenuator 11 has a cylinder 16 which is divided by a piston 17 into a first pressure chamber 18 and into a second pressure chamber 19. The piston 17 is connected via a piston rod 20 with the spring rocker 8. On the piston rod 20 opposite Side a second piston rod 21 is arranged, which has the same diameter as the first piston rod 20. The second piston rod 21 is guided in a blind bore 22 in an end face 23 of the cylinder 16, which faces the machine frame 10. Thus, the two pressure application surfaces on the piston 17 are the same size. During a movement of the piston 17 is always displaced from a pressure chamber 18, 19 always as much hydraulic fluid, as can be absorbed by the other pressure chamber 19, 18. The volume available for the hydraulic fluid remains constant, so that no external storage is required.

Of course, you can also use the attenuator when the piston 17 is connected to the machine frame 10 and the cylinder 16 with the spring arm 8.

Only schematically are seals 24, 25, 26 shown, which seal the two pressure chambers 18, 19 to each other or to the outside.

The two pressure chambers 18, 19 are connected by a connecting path 27 with each other. In the connecting section 27, a throttle 28 is arranged. In addition, a switching valve 29 is arranged in the connecting section 27, which can be actuated via an input 30 of the above-mentioned control device 13.

In the piston 17, a pressure compensating throttle 31 is arranged, whose flow resistance is substantially greater He should be so large that at higher frequencies in the order of 30 Hz, the volume of the hydraulic fluid in the two pressure chambers 18, 19 is clamped, so to speak, when the switching valve 29 is closed. Moreover, the pressure equalizing throttle 31 should only let through a comparatively small proportion of the hydraulic fluid, which is displaced from one pressure chamber 18 to the other pressure chamber 19 or vice versa. The pressure compensation throttle 31 is used to allow a pressure equalization between the two pressure chambers 18, 19 when the switching valve 29 is closed, when the weight of the winding roll 5 increases.

The two pressure chambers 18, 19 are connected to a circulation flow generating device 32. The circulation flow generating device 32 has a pump 33 which extracts hydraulic fluid from a tank 34 and pumps it back into the tank 34 through the two pressure chambers 18, 19. Between the tank 34 and the pump 33, a tempering device 35 may be provided, which keeps the hydraulic fluid at a constant temperature as possible. This is advantageous in order to keep the damping properties of the attenuator 11 constant over a longer period of time. The damping depends inter alia on the resistance that the hydraulic fluid in the throttle 28 is exposed to. This flow resistance in turn depends on the viscosity of the hydraulic fluid and thus on the temperature of the hydraulic fluid.

Deviating from the embodiment shown in Fig. 2, it is of course also possible to provide each pressure chamber 18, 19 with its own connection for both the inflow and for the outflow of hydraulic fluid, so that a flow can be ensured even if the Switching valve 29 is closed.

The attenuator 11 now works as follows:
For damping, the two pressure chambers 18, 19 are connected to each other via the open switching valve 29 and the throttle 28. During a swinging bearing movement, the hydraulic fluid is pumped back and forth via the throttle 28 from one pressure chamber 18, 19 to the other pressure chamber 19, 18. The throttle 28 may be a frequency wise optimally designed constant throttle or a variable throttle point. In the flow through the throttle 28 generates frictional heat. This frictional heat is energy that is removed from the oscillation process. It is also referred to as "damping energy" for short, which is discharged to the tank 34.

Should it still come to a self-excited oscillation in this basic operating mode, ie the damped operation, the reel winding device, then the bearing stiffness of the support rollers 2, 3 can be changed very quickly by closing the switching valve 29. With the switching valve 29, the connecting path 27 between the two pressure chambers 18, 19 is interrupted. By shutting off the damping effect of the cylinder 16 is turned off with the piston 17 and the in The hydraulic fluid clamped in the pressure spaces 18, 19 acts like a rigid support roller bearing.

As a result of the suddenly stiffened mounting of one or even both support rollers 2, 3, the natural frequency of the system formed by the two support rollers 2, 3 and the winding roller 5 and thus also the feedback mechanism of wavy winding rollers in the winding bed 4 changes.

In order to avoid a jolt of the support rollers 2, 3 due to a pressure difference in the two pressure chambers 18, 19 in a possible switching back to the muted operating mode, ie when opening the connecting path 27, the pressure compensation throttle 31. By the pressure compensation throttle is in the long-term range a static Pressure equalization due to the growing weight of the winding roll 5 instead. However, the pressure compensation throttle 31 must be dimensioned so narrow that the momentarily moving oil volume of the hydraulic fluid in the frequency range of 30 - 40 Hz in the pressure chambers 18, 19 acts in a dynamic manner as firmly clamped. This is usually the case when the acceleration forces, which are necessary for conveying the hydraulic fluid through the connecting path 27, are substantially greater than the frictional forces which are necessary for the passage of the pressure compensation throttle 31.

Such an attenuator has basically integrated all the necessary elements, ie you do not need a complex external wiring with a pressure control loop or a pressure accumulator. In addition, such a reel winding device 1 is relatively low maintenance and allows safe operation.

Claims (14)

Roller winding device with at least one roller on which a winding roller bears during winding and which is mounted in a roller bearing, characterized in that the roller bearing (6, 7) via an attenuator (11, 12) with a support (10) is connected, the a cylinder (16) and a piston (17) arranged therein, which divides the cylinder (16) into two pressure chambers (18, 19), the piston (17) with the roller bearings (6, 7) and the cylinder (16) 16) is in communication with the support (10) and the two pressure chambers (18, 19) via a connecting path (27) containing at least one throttle (28) are connected. Roller winding device according to claim 1, characterized in that the permeability of the connecting path (27) is variable. Roller winding device according to claim 1 or 2, characterized in that in the connecting path (27) a switching valve (29) is arranged, with which the connecting path (27) can be interrupted. Roller winding device according to one of claims 1 to 3, characterized in that the piston (17) in both pressure chambers (18, 19) has the same size pressure application surfaces. Roll winding device according to one of claims 1 to 4, characterized in that the two pressure chambers (18, 19) are connected to a circulation flow generating device (32). Roller winding device according to claim 5, characterized in that the circulation flow generating device (32) has a tempering device (35). Roll winding device according to one of claims 1 to 6, characterized in that the two pressure chambers (18, 19) are additionally connected to each other by a pressure equalizing throttle (31). Roller winding device according to Claim 7, characterized in that the pressure compensation throttle (31) is arranged in the piston (17). Roller winding device according to claim 7 or 8, characterized in that the pressure compensation throttle (31) has a much greater throttle resistance than the throttle (28). Roller winding device according to one of claims 1 to 9, characterized in that the roller bearing (6, 7) via a spring (8, 9) with the support (10) is connected. Roller winding device according to claim 10, characterized in that the spring (8, 9) is arranged parallel to the throttle member (11, 12). Roller winding device according to claim 10 or 11, characterized in that the spring (8, 9) is formed by a spring rocker. Roller winding device according to claim 10 or 11, characterized in that the roller bearing (6, 7) is mounted on an articulated arm, which is supported by a spring element on the support (10). Roller winding device according to one of claims 2 to 13, characterized in that two rollers (2, 3) with roller bearings (6, 7) are provided which are each connected via an attenuator (11, 12) to the support (10), wherein a control device (13) is provided, the vibration-dependent the permeability of the connecting path (27) one of the throttle member (11) or the other throttle member (12) or both throttle members (11, 12) changed.

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