Patent Grant
6878237
The present application claims priority under 35 U.S.C. §119 of German Patent Application No. 102 13 851.6, filed on Mar. 27, 2002, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The present invention relates to a process for operating a machine, e.g., a paper machine, a stand alone (off-line) calender, speed sizer, size press, etc., in which vibrations that occur on at least one roll and/or in at least one nip formed between a roll and an opposing surface, in particular an opposing roll, are monitored. It further relates to a corresponding machine, e.g., a paper machine, a stand alone (off-line) calender, speed sizer, size press, etc.
2. Discussion of Background Information
Processes and paper machines of the type mentioned at the outset are described in International Publication No. WO 99/20836 and in European Patent Application No. EP 0 779 394 A1.
Transverse stripes can occur on the paper web, in particular in connection with the use of roll coatings, e.g., in machine calenders, calenders, coating units, in particular size presses and/or the like. As soon as these stripes become visible, the paper web is unusable and forms broke. This so-called “barring effect” is probably the effects of vibration phenomena.
The present invention provides an improved process and an improved machine of the type mentioned at the outset, with which an early recognition of the barring effect, of wavinesses in the roll covering and/or similar phenomena is possible, in order if necessary to be able to start appropriate countermeasures in time.
The present invention includes a process for operating a machine, e.g., a paper machine, a stand alone (off-line) calender, speed sizer, size press, etc., in which vibrations that occur on at least one roll and/or in at least one nip formed between a roll and an opposing surface, in particular an opposing roll, are monitored by a sound measurement conducted in the area of the roll or in the area of the nip.
Due to this embodiment, the barring effect can be recognized at a very early stage, so that it is now possible to start countermeasures in time. As a result above all longer roll service lives are thus obtained.
According to a preferred practical embodiment of the process according to the invention, an airborne sound measurement is conducted.
The sound measurement is made advantageously in the direct proximity of the roll or the nip.
The sound measurement can be conducted and/or analyzed repeatedly, whereby preferably a periodic sound measurement or analysis is provided. However, in principle a continuous sound measurement and/or analysis is also possible.
For instance, a respective sound level measurement or sound intensity measurement can be made.
The sound measurement is advantageously conducted by at least one sound sensor, in particular a sound pressure sensor, in particular a microphone.
A preferred practical embodiment of the process according to the invention is remarkable because an obtained sound measurement value or a value derived from it is compared with a preset upper limit value and, if this limit value is exceeded, the exceeding of the limit value is signaled and/or control and/or regulating steps are activated which counteract the vibrations or reduce the vibrations to a minimum.
The sound measurement is advantageously conducted in the area of at least one roll with a tendency towards a barring effect or in the area of at least one nip with a tendency towards such a barring effect. The sound measurement can thereby be conducted in particular in the area of at least one roll provided with a covering and/or in the area of at least one elastic roll.
The sound measurement can be conducted, e.g., in the area of a calender, a machine calender, a size press, a guide roll and/or the like.
A respective sound measurement can be conducted, e.g., in the area of the jacket of the respective roll, in the area of a roll bearing and/or in the area of a roll face.
The vibrations detected in the manner described can be counteracted by various actuators or measures.
According to a preferred practical embodiment of the process according to the invention, the vibrations are counteracted via a corresponding roll displacement in the axial direction and/or in the machine running direction. Such a measure is particularly advantageous with a calender. A roll displacement preferably occurs in the machine running direction.
According to another advantageous embodiment the vibrations are counteracted via a corresponding control and/or regulation of the rigidity and/or the damping of an active roll bearing. An active roll bearing can thereby be used, e.g., as described in German Patent Application No. DE 100 19 506 A1.
In certain cases it is also advantageous to counteract the vibrations via a corresponding control and/or regulation of the roll- and/or roll coating temperature. A corresponding control and/or regulation of the cooling water temperature or the cooling water effect, for example, can thereby be provided.
With a sag compensation roll, the vibrations can be counteracted, e.g., via a corresponding control and/or regulation of the damping of the hydraulic system of the inner support sources of the sag compensation roll.
With a size press, the vibrations can be counteracted, e.g., via a corresponding control and/or regulation of the paint- or glue temperature and/or the viscosity of the respective paint- or glue material.
The sound measurement values obtained are preferably subjected to a frequency analysis. A so-called fast Fourier transform is suitable in particular thereby.
In a practical embodiment the entire spectrum is measured or considered in the sound measurement and/or in the sound analysis.
In another preferred practical embodiment of the process according to the invention, only at least one preset frequency band is measured or considered in the sound measurement and/or sound analysis.
According to another preferred practical embodiment of the process according to the invention, the sound measurement is conducted for at least one preset frequency and/or at least one sound measurement value obtained for a preset frequency is compared with a preset upper limit value. For example, at least one barring frequency that can be determined in advance can thereby be considered.
The invention is also directed to a machine with a device for monitoring vibrations that occur on at least one roll and/or in at least one nip formed between a roll and an opposing surface, in particular an opposing roll, whereby the monitoring device comprises a sound measurement device through which a sound measurement can be conducted in the area of the roll or in the area of the nip.
The present invention is directed to a machine. The machine includes at least one roll and an opposing surface. The at least one roll and the opposing surface are arranged to form at least one nip. A sound measuring device is arranged to conduct sound measurements in at least one of an area of the at least one roll and an area of the at least one nip to monitor vibrations in the at least one roll and/or in the at least one nip.
According to a feature of the invention, the opposing surface can include an opposing roll.
In accordance with another feature of the invention, the sound measuring device may include an airborne sound measurement.
The sound measuring device can be structured and arranged for measuring sound in direct proximity of the at least one roll or the at least one nip.
Further, the sound measuring device may be is structured to at least one of repeatedly conduct and repeatedly analyze sound measurement. The sound measuring device can be structured to at least one of periodically conduct and periodically analyze sound measurements.
According to the invention, the sound measuring device can be structured to at least one of continuously conduct and continuously analyze sound measurements.
In accordance with another feature of the present invention, the sound measuring device can include a sound level measurement device.
According to still another feature, the sound measuring device may include a sound intensity measurement device.
The sound measuring device can include at least one sound sensor. Further, the at least one sound sensor may include comprises a sound pressure sensor, and the sound pressure sensor can include a microphone.
The sound measuring device can include comprises a control and/or regulating device structured and arranged to compare a measured sound value with a preset upper limit value. The control and/or regulating device may include actuators such that, if the upper limit value is exceeded by the measured sound value, the actuators are arranged to actuate at least one of a signal device and/or a device for counteracting the vibrations or for reducing the vibrations to a minimum.
In accordance with a further feature of the invention, the at least one roll can exhibit a tendency towards a barring effect or the at least one nip can exhibit a tendency towards a barring effect.
According to a still further feature of the instant invention, the at least one roll can include a covering, and the at least one roll may include an elastic roll.
Moreover, the at least one roll can be arranged within a calender, a machine calender, a size press, and a guide roll.
Still further, the at sound measuring device can be positioned in an area of a roll jacket of the at least one roll.
In accordance with another feature of the instant invention, the sound measuring device can be positioned in an area of a roll bearing of the at least one roll.
According to still another feature, the sound measuring device may be positioned in an area of a roll face of the at least one roll.
The sound measuring device can include a vibration counteracting device structured and arranged to displace the at least one roll in at least one of an axial direction and a machine running direction.
Further, the sound measuring device may include a vibration counteracting device structured and arranged to control and/or regulate at least one of a rigidity and damping of an active roll bearing of the at least one roll.
Still further, the sound measuring device can include a vibration counteracting device structured and arranged to control and/or regulate at least one of roll temperature and roll coating temperature of the at least one roll.
Moreover, the sound measuring device can include a vibration counteracting device structured and arranged to control and/or regulate a cooling water temperature of the at least one roll.
According to a further feature of the invention, the at least one roll can include a sag compensation roll having a hydraulic system of inner support sources and the sound measuring device may include a vibration counteracting device structured and arranged to control and/or regulate a damping of the hydraulic system of the sag compensation roll.
In accordance with a still further feature of the instant invention, the at least one roll can be arranged in a size press, and the sound measuring device may include a vibration counteracting device structured and arranged to control and/or regulate a paint or glue temperature and/or a viscosity of a paint or glue material.
Further, the sound measuring device can include an analyzing unit structured and arranged to subject sound values obtained by the sound measuring device to a frequency analysis. The analyzing unit can analyze an entire spectrum of the sound values.
According to another feature of the invention, the analyzing unit can analyze preset frequency bands of the sound values.
In accordance with still another feature of the present invention, the sound measuring device can be structured to measure at least one preset frequency of sound, and the machine may further include a comparing unit structured to compare a value of the measured at least one preset frequency of sound with a preset upper limit value.
According to the invention, the machine can be a paper machine, or a stand alone calender, or a speed sizer or size press.
The present invention is directed to a process for operating a machine having at least one roll and an opposing surface arranged to form at least one nip. The process includes rotating the at least one roll, whereby vibrations occur on the at least one roll and/or in at least one nip, and measuring sound conducted in an area of the at least one roll or in an area of the at least one nip.
In accordance with a feature of the invention, the opposing surface can include an opposing roll.
According to another feature of the instant invention, the sound measuring can include an airborne sound measurement.
In further accordance with the invention, the sound measuring can be performed in direct proximity of the at least roll or the least nip.
The process can further include repeatedly conducting and/or repeatedly analyzing the sound measuring. The sound measuring can be conducted periodically and/or analyzed periodically.
Moreover, the process can also include continuously conducting and/or analyzing the sound measuring.
According to still another feature of the present invention, the sound measuring can include a sound level measurement.
In accordance with a further feature, the sound measuring can include a sound intensity measurement.
The sound measuring can be performed by at least one sound sensor. The at least one sound sensor can include a sound pressure sensor, and the sound pressure sensor may include a microphone.
The process can also include comparing a value of the measured sound with a preset upper limit value and, if the value exceeds the upper limit value, at least one of signaling the exceeding the limit value and controlling and/or regulating actions to counteract the vibrations or reduce the vibrations to a minimum.
Still further, the at least one roll exhibits a tendency toward a barring effect and the at least one nip exhibits a tendency towards such a barring effect.
According to another feature of the present invention, the at least one roll may have at least one of a covering and is an elastic roll.
Further still, the at least one roll can be located in at least one of a calender, a machine calender, a size press, and a guide roll.
In accordance with the invention, the sound measuring may be performed in an area of a roll jacket of the at least one roll.
According to another feature, the sound measuring can be performed in an area of a roll bearing of the at least one roll.
According to still another feature of invention, the sound measuring can be performed in an area of a roll face of the at least one roll.
The process can further include counteracting the vibrations by displacing the at least one roll in at least one of an axial direction and a machine running direction.
According to another feature of the invention, the process may further include counteracting the vibrations by at least one of controlling and regulating at least one of a rigidity and or damping of an active roll bearing of the at least one roll.
In accordance with a further feature of the present invention, the process can also include counteracting the vibrations by at least one of controlling and regulating at least one of roll temperature and roll coating temperature.
Moreover, the process may include counteracting the vibrations by at least one of controlling and regulating a cooling water temperature.
Still further, the at least one roll can include a sag compensation roll having a hydraulic system for inner support sources, and the process can include counteracting the vibrations by at least one of controlling and regulating a damping of the hydraulic system of the inner support sources.
The at least one roll can be located in a size press, and the process may further include counteracting the vibrations by at least one of controlling and regulating at least one of a paint or glue temperature and a viscosity of the paint or glue material.
The process may also include analyzing sound values obtained through the sound measuring with a frequency analysis. An entire spectrum of the measured sound can be analyzed. At least one preset frequency band of the measured sound may be analyzed. Further, only one preset frequency band of the measured sound can be analyzed.
In accordance with still yet another feature of the present invention, the sound measuring can be performed for at least one preset frequency, and at least one sound value obtained through the sound measuring for a preset frequency may be compared with a preset upper limit value.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.
The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:
The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
Monitoring device 10 comprises at least one sound sensor 20 which can be in particular a sound pressure sensor, e.g., a microphone.
Roll 12 is, e.g., a roll with a tendency towards a barring effect. In the present case sound sensor 18 is arranged in the direct proximity of jacket 12′ of roll 12.
Sound sensor 18 is part of a sound measurement device 20, e.g., integrated into monitoring device 10. In the present case, sound measurement device 20 or sound sensor 18 is embodied for an airborne sound measurement.
Monitoring or sound measurement device 10 and/or 20 can be embodied in particular such that the sound measurement and/or analysis can be conducted repeatedly. A periodic sound measurement or sound analysis is thereby preferably provided. However, in principle the sound measurement or sound analysis can also occur continuously.
For example the sound level and/or the sound intensity can be measured by sound sensor 18.
Monitoring device 10 can comprise in particular a control and/or regulating device 22. Thus, in particular at least one automatic control loop or control circuit for active and/or passive measures can be provided in monitoring system 10.
Monitoring system 10 including control and/or regulating device 22 can be designed in particular such that a respective obtained sound measurement value or a value derived from it is compared with a preset upper limit value and in the event of this limit value being exceeded the exceeding of the limit value is signaled and/or control and/or regulating steps activated which counteract the vibrations or reduce the vibrations to a minimum.
Roll 12 can be provided, e.g., with a coating and/or formed by an elastic roll.
The sound measurement can be conducted, e.g., in the area of a calender, a machine calender, a size press and/or the like. It can also be conducted, e.g., on a guide roll.
Sound sensor 18 can be in particular again a sound pressure sensor, e.g., a microphone.
Otherwise the monitoring device can be embodied again in particular as is described in connection with FIG. 1.
Also, in the present case, sound sensor 18 can be, e.g., a sound pressure sensor, e.g., a microphone. As with the other exemplary embodiments, in principle, e.g., a sound level measurement or a sound intensity measurement is conceivable.
Otherwise, monitoring device 10 can be embodied in particular again as described in connection with FIG. 1.
The left part of
By the fast Fourier transform (FFT), sound measurement signal 36 is transferred into the frequency area (see the right-hand portion of FIG. 4). In the respective diagram in the right part of
The amplitudes obtained in the frequency area for the various frequencies vi are each compared with a preset upper limit value 38 in order to be able if necessary to start active and/or passive measures if this limit value is exceeded. In the present case, limit value 38 is exceeded by the amplitudes at frequencies v1 and v2. If these are critical frequencies, e.g., with regard to the mentioned barring effect, the relevant measures are to be taken. Exceeding limit value 38 can be, e.g., an indication that the rolls are becoming non-circular. The relevant vibrations can then be counteracted, e.g., by a corresponding roll displacement.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102 13 851 | Mar 2002 | DE | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4505154 | Wiesner | Mar 1985 | A |
| 5083976 | McClure et al. | Jan 1992 | A |
| 5768985 | Lehtovirta et al. | Jun 1998 | A |
| 5915297 | Lehtovirta et al. | Jun 1999 | A |
| 5971315 | Kojo | Oct 1999 | A |
| 6270628 | Suomi et al. | Aug 2001 | B1 |
| 6387214 | Kustermann et al. | May 2002 | B1 |
| 6463775 | Kodama et al. | Oct 2002 | B1 |
| 6500304 | Holopainen et al. | Dec 2002 | B1 |
| 6750621 | Gandrud | Jun 2004 | B2 |
| 20020060021 | Kayser et al. | May 2002 | A1 |
| 20040079147 | Maenpaa | Apr 2004 | A1 |
| Number | Date | Country |
|---|---|---|
| 10019506 | Jan 2001 | DE |
| 10008800 | Sep 2001 | DE |
| 0779394 | Jun 1997 | EP |
| 779394 | Jun 1997 | EP |
| 9920836 | Apr 1999 | WO |
| 9920836 | Apr 1999 | WO |
| 0009805 | Feb 2000 | WO |
| WO 0072989 | Dec 2000 | WO |
| 0150030 | Jul 2001 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20030188583 A1 | Oct 2003 | US |
