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EP 1 773 701 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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23.03.2011 Bulletin 2011/12 |
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Date of filing: 30.06.2005 |
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International Patent Classification (IPC):
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International application number: |
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PCT/FI2005/050254 |
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International publication number: |
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WO 2006/003258 (12.01.2006 Gazette 2006/02) |
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A METHOD IN A REEL-UP AND A REEL-UP
VERFAHREN ZUM AUFWICKELN UND WICKLER
PROCEDE DANS UNE ENROULEUSE ET ENROULEUSE
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Designated Contracting States: |
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AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI
SK TR |
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Priority: |
30.06.2004 FI 20045254
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Date of publication of application: |
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18.04.2007 Bulletin 2007/16 |
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Divisional application: |
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10175579.1 / 2256074 |
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Proprietor: Metso Paper, Inc. |
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00130 Helsinki (FI) |
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Inventors: |
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- LANNES, Petteri
FI-05400 Jokela (FI)
- PITKÄNEN, Tatu
FI-04400 Järvenpää (FI)
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Representative: Rönkkö, Taina Mirjam |
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Tampereen Patenttitoimisto Oy
Hermiankatu 1 B 33720 Tampere 33720 Tampere (FI) |
(56) |
References cited: :
EP-A- 0 860 391 WO-A-03/004389 US-A- 4 883 233 US-A- 5 150 850 US-A- 5 944 273
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WO-A-98/55384 US-A- 4 476 076 US-A- 5 048 353 US-A- 5 901 918 US-B1- 6 698 681
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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Field of the invention
[0001] The invention relates to a method in a reeler, wherein the reeling nip is formed
by a reeling core or a growing machine reel and at least one loop of an endless supporting
member that is substantially continuous in the axial direction of the reeling core.
The invention also relates to a reeler for implementing the aforementioned method.
Background of the invention
[0002] In the final end of a machine manufacturing paper, paperboard, soft tissue or the
like or a finishing apparatus for paper, paperboard or soft tissue or the like, a
paper web which is typically several meters wide and which has been produced and/or
treated in the preceding machine sections, is reeled around a reeling shaft, i.e.
a reel spool to form a machine reel. In this reeling up process a reeling cylinder
that is bearing-mounted rotatable is typically used for guiding the paper web on the
machine reel, wherein the nip contact between the reeling cylinder and the machine
reel is utilized to influence the quality of the reel produced thereby. The ends of
the reel spool are affected by means of a suitable loading mechanism to adjust the
nip contact between the machine reel that is being formed and the reeling cylinder.
Such reeling concepts and loading methods related thereto are disclosed, for example,
in the Finnish patent
91383 and in the corresponding
US patent 5,251,835, as well as in the Finnish patent application
950274 and in the corresponding
US patent 5,690,298.
[0003] The measurement of the cross-directional profile of such a reeler is disclosed for
example in the
US patent 5,048,353 in which one or several sensors operating on piezoelectric principle have been installed
on the surface layer of the reeling cylinder, said sensors reacting to the pressure
prevailing in the nip. The sensors have been installed spirally around the length
of the reeling cylinder so that they measure the cross-directional profile of the
pressure prevailing in the reeling nip.
[0004] In addition, the publication
EP-860391 discloses a reeler, in which the web is guided on a reel via a supporting member
formed of several endless belts or wires arranged next to each other in the longitudinal
direction of the guide roll, said supporting member being passed via the guide rolls.
Thus, by means of the belt loops it is possible to attain a long reeling nip having
an even pressure in the area of the lower half of the reel. The aim is to control
the pressure through the tension of individual belt loops. According to the publication,
it is possible to profile the nip pressure on the basis of the measured tension of
individual belt loops. It is a problem in this solution that because the supporting
member is composed of several belt loops arranged next to each other in the longitudinal
direction of the guide roll, it is difficult to monitor the condition of the belts,
and maintain and repair them. Furthermore, it is difficult to control the rotation
speed of separate belt loops, and it requires separate controlling means. It is also
difficult to hold the belts moving in the machine direction in their correct locations
in the longitudinal direction of the guide rolls so that they do not drift on top
of each other. In addition, each belt loop requires separate belt tensioning means
for controlling the pressure of the reeling nip, which means cause a lack of space
in the surroundings of the reeler.
[0005] WO publication 98/55384 discloses a reeler in which the reeling nip is formed by means of a loop of a supporting
member and a reel spool. The total tension of the belt is controlled by means of load
cells attached to a guide roll guiding the belt. The total tension of the belt thus
attained is also used for controlling the nip pressure of the reeling nip.
[0006] Further, from a Finnish patent publication
20010621 it is known to measure the cross-directional (i.e. CD-directional) tension profile
of the texture conveying the paper web, i.e. the wire or the felt. This profile data
has been used for the process control taking place on the range of influence of the
texture.
[0007] Both when using a conventional reeler based on a reeling cylinder and a belt reeler
utilizing a supporting member according to the above-mentioned
EP publication 860391 and
WO publication 98/55384 there is a basic problem in the reeling process: it is difficult to get an even cross-directional
profile in the machine reel that is being produced. Consequently, the irregularities
produced in the reeling, such as creases caused by the slackness of the belt, and
local dents caused by excessive tension of the web, transfer to the customer rolls.
In the above-mentioned publications attempts have been made to solve this problem
by means of controlling the cross-directional linear pressure of the reeling nip.
This is, however, difficult, because the controlling requires exact measuring results.
The measurement of the total tension of the belt used in the reeling as presented
in the above-mentioned publications is not an accurate enough variable for accurate
controlling. The document
US 6,698,681 is considered as closest prior art.
Brief description of the invention
[0008] The purpose of the present invention is thus to provide a method in a reeler, by
means of which the above-mentioned problems can be avoided and the tension profile
of a belt reeler or the cross-directional linear load profile of the reeling nip can
be accurately and reliably determined, in which belt reeler, i.e. a reel up, the reeling
nip is formed by means of a flexible supporting member, such as belt or a wire, in
the form of an endless loop that is continuous in the axial direction of the reeling
core. Variables proportional to the tension of a supporting member are measured and
from the tension profile determined from them it is possible to calculatorily determine
the cross-directional linear load profile (i.e. CD-profile) of the reeling nip, or
other parameters connected to the operation of the supporting member. If the target
of the measurement is the cross-directional linear load profile of the reeling nip,
the above-mentioned parameters can be determined directly from that. It is also an
aim of the invention to provide a reeler implementing the aforementioned method.
[0009] The method in a reeler according to the invention is characterized in that the cross-directional
linear load profile of the reeling nip is measured by means of at least one measuring
means that is arranged to the supporting member.
[0010] The reeler according to the invention is characterized in that at least one measuring
means is arranged to the supporting member in order to measure the cross-directional
linear load profile of the reeling nip.
[0011] The other, dependent claims present some preferred embodiments of the invention.
[0012] In this description and in the claims the term endless supporting member refers to
a flexible belt or wire in the form of an endless loop that is substantially continuous
in the axial direction of the reeling core, the width of which belt or wire is substantially
equal to the width of the web to be reeled, and which travels in the machine direction
by the effect of the rotating movement of the guide rolls. The belt reeler, in turn,
refers to a reeler in which the reeling nip is formed by means of the above-presented
supporting member and a growing machine reel. The reeling core refers to a core or
a reel spool, around which the web of paper, paperboard, tissue or the like is reeled.
[0013] The variables proportional to the tension of the endless supporting member that is
substantially continuous in the longitudinal direction of the reeling core, or the
cross-directional linear load profile of the reeling nip are measured with at least
one measuring sensor placed in at least one guide roll controlling the supporting
member or in the supporting member itself. Of the measured variables proportional
to the tension of the supporting member is determined the cross-directional tension
profile of the supporting member. The measuring sensor is, for example, a sensor operating
on piezoelectric principle, for example an EMFi film, which changes the pressure or
force directed to it into an electric output signal. Other sensors operating on piezoelectric
principle, such as, for example, PVDF film and separate piezocrystal sensors, can
also be used in the measuring. It is also possible to use other capacitive, resistive
and inductive sensors suitable to be attached on the surface of the roll or on the
supporting member, as well as other sensors measuring pressure or force in order to
measure tension. For example, strain gauges can be attached on the surface of the
roll or the supporting member suitably spaced to measure the tension of the supporting
member, of which measurement it is possible to form a tension profile. Suitable sensors
are typically of such a type that they are capable of changing the pressure or load
exerted thereto into a signal that can be conducted via a suitable conductor or wirelessly
to a data processing unit, in which it can be processed in a manner known from processing
of measurement signals.
[0014] When the above-mentioned sensors are attached to the guide roll, they measure the
load or pressure directed by the supporting member to the surface of the guide roll,
in which case a greater pressure/force is directed to the sensor at the tight zones
of the belt than at the slack zones, in which case a cross-directional tension profile
of the supporting member, i.e. a CD-profile is created. Thus, in the calculation of
the tension profile of the supporting member it is possible to utilize either the
pressure/load measured in the direction of radius, perimeter or axis of the guide
roll, or both, depending on the measuring method.
[0015] When sensors attached to the guide roll are used in the measuring, they are arranged
to the roll either to circle the roll in a spiral-like manner over its entire length
or to extend over the length of the roll directly in its axial direction. The film-like
sensors can be placed to the roll as a narrow band or as separate sequential strips.
The sensors can be arranged either on the surface of the roll, on top of the roll
coating or under the coating layer/layers in such a manner, however, that the coating
over the sensor does not cause significant deterioration of the measuring accuracy.
[0016] The measuring results provided by the sensors attached to the roll are transferred
advantageously wirelessly from the roll, for example, by means of a slide ring or
a transfer method based on telemetry.
[0017] As stated above, the sensors attached to the supporting member may also be point-like
sensors, narrow, band-like sensors or separate strips positioned successively. The
sensors are arranged to the supporting member in such a manner that they extend substantially
over its width. The measuring sensors can be arranged so that they replace the wire
threads or they can be arranged between the wire threads. The essential aspect is
that they do not leave marks on the web to be reeled. The supporting member can also
be formed entirely of several overlapping layers, at least one of which operates as
the sensor performing the measurements.
[0018] The measuring sensors arranged to the supporting member measure the variables needed
for determining the tension profile of the supporting member in the reeling nip, i.e.
when the part of the supporting member comprising the measuring sensors and the reel
spool or the machine reel that is being formed are in contact with each other. The
cross-directional linear load profile of the reeling nip is attained directly from
these measurements, and a calculatory conversion tension profile -> cross-directional
profile of the linear load is not necessary.
[0019] The measurement results from the measuring sensors attached to the supporting member
can be transferred out of the sensor in a number of different ways, for example by
means of slide wires positioned on the surface of the supporting member and brushes
attached to one guide roll, wherein the measurement information can be transferred
outside through the guide roll. The measurement information can be transferred out
of the supporting member in a wireless manner as well, for example by means of a transmitter
positioned in the supporting member, and the signal transmitted by said transmitter
is received in a receiver positioned in the vicinity of the supporting member. Inside
the loop of the supporting member it is also possible to place a beam-like data transmission
means perpendicularly to the width of the supporting member and transmitting information
in a contactless or contact-oriented manner.
[0020] From the tension profile of the endless supporting member determined from the measurements
of the supporting member, it is possible to determine the cross-directional linear
load profile of the reeling nip of the belt reeler, by means of which it is possible
to determine the structure of the growing machine reel. In addition, it is possible
to determine other parameters of the machine reel, such as the diameter profile of
the machine reel forming in the reeling. In addition, the tension profile of the supporting
member can be utilized in monitoring the condition of the supporting member, in monitoring
the position of the supporting member and in determining the average tension of the
supporting member. If the measured variable is the cross-directional linear load profile
of the reeling nip, the above-mentioned parameters can be determined directly from
the measurement results.
[0021] In the belt reeler the endless supporting member travels in the machine direction
of the paper machine guided by at least two guide rolls. In the measurement of variables
proportional to the tension of the supporting member using guide rolls according to
the invention it is substantial, that at least one guide roll used in the measurement
is after the reeling nip in the machine direction. It has surprisingly been noted
that the form of the surface of the growing machine reel, i.e. the bumps and dents
in the reel and therefore also the cross-directional linear load profile of the reeling
nip in the longitudinal direction of the machine reel (in the CD-direction) is copied
in the reeling nip to the endless supporting member that is in contact with the machine
reel, and therefore it shows in the tension measurement results of the supporting
member measured after the reeling nip and the tension profile formed from them.
[0022] The determination of the tension profile of the supporting member can also take place
by placing the above-mentioned measuring sensors to two guide rolls in such a manner
that one of the rolls is located before the reeling nip and the other one after it,
in which case the measuring values proportional to the tension provided by the rolls
and the tension profiles formed of them can be compared and the tension profile of
the supporting member can be determined on the basis of their difference. If the tension
profile is used in determining the cross-directional linear load profile of the reeling
nip, it is advantageous to use the tension profile formed of at least one of the measuring
results attained from the roll comprising a measuring sensor, which roll directs the
supporting member and is within the loop of the supporting member. Another tension
profile used in the determination is formed on the basis of other measurements received
from the guide roll that is in contact with the belt. The tension profile of the supporting
member and the cross-directional linear load profile of the reeling nip can be determined
from the difference between the thus formed tension profiles.
[0023] It is also possible to use a method where the cross-directional tension profile of
the supporting member is determined on the basis of the measuring results of measuring
sensors placed in at least one guide roll directing the supporting member, and so
that the reeling nip is closed, i.e. the forming machine reel is in contact with the
supporting member as well as without the machine reel contacting the supporting member.
By comparing the formed cross-directional tension profile of the supporting member
loaded with a machine reel to such a tension profile that is formed of an unloaded
supporting member, it is possible to determine the form profile of the surface of
the machine roll, i.e. the structure of the roll from these. Naturally, the cross-directional
linear load profile of the reeling nip is also provided by the same difference.
[0024] According to the invention, the tension profile of the supporting member determined
from the variables proportional to the tension of the supporting member or the measured
cross-directional linear load profile of the reeling nip can also be utilized in monitoring
the condition of the supporting member. Local wearing of the texture of the supporting
member causes a change in the tension profile or the cross-directional linear load
profile of the reeling nip, which can be recognised from the profile and thus information
on the condition of the supporting member can be received. In this manner, it is possible
to monitor the condition of the supporting member and to anticipate, for example,
the need for changing the supporting member, i.e. the belt or the wire, before the
worn or damaged supporting member has time to cause damages to the reeled web or other
damages. Further, the tension profile of the supporting member determined from the
variables proportional to the tension of the supporting member or the measured cross-directional
linear load profile of the reeling nip according to the invention can also be applied
in the belt reeler in monitoring the position of the supporting member in the longitudinal
direction of the roll directing the supporting member and through that in adjusting
the controller of the supporting member as well. The method of the patent publication
FI-20012528 that is known as such can be applied here.
[0025] The measurement of variables proportional to the tension of the supporting member
according to the invention and the determination of the tension profile of the supporting
member is simple and fast. The sensors used in the measurement do not take space in
the vicinity of the reeler and they can be easily placed to the guide rolls in contact
with the supporting member, and they do not cause wearing of the supporting member.
When the sensors have been placed to the supporting member, it is possible to measure
the cross-directional linear load profile of the reeling nip between the reel and
the supporting member directly without measuring the variables proportional to belt
tension. Thus, a calculatory conversion from the tension profile of the supporting
member to the cross-directional linear load profile is not needed either. If the determination
of the linear load profile of the reeling nip is performed calculatorily from the
measurement results attained from the sensors, it does not require separate devices
taking room at the reeler. The invention utilizes in a new and excellent manner the
methods known as such for measuring the variables proportional to the tension of the
texture of a paper machine and for determining the tension profile, or for measuring
the cross-directional linear load profile of the reeling nip, and introduces new way
to monitor the parameters connected to the operation of the supporting member, such
as the condition of the supporting member and its position on the guide rolls.
Brief description of the drawings
[0026] In the following, the invention will be described in more detail with reference to
the appended drawings, in which
- Fig. 1
- illustrates schematically the main principle of a belt reeler in a side view,
- Fig. 2
- shows schematically a guide roll used in the method according to the invention, in
which guide roll is arranged a measuring sensor,
- Fig. 3
- shows schematically another guide roll used in the method according to the invention,
in which guide roll is arranged a measuring sensor,
- Fig. 4
- shows a measurement arrangement according to the invention in a perspective view,
- Fig. 5
- shows schematically a supporting member used in the method according to the invention
in a top view from the side,
- Fig. 6
- shows schematically another supporting member used in the method according to the
invention in a top view from the side,
- Fig. 7
- shows a cross-section of a supporting member used in the method according to the invention,
- Fig. 8
- shows schematically the cross-directional tension profiles of the supporting member,
- Fig. 9
- shows schematically the cross-directional tension profiles of the supporting member
used in connection with monitoring the condition of the supporting member, and
- Fig. 10
- shows schematically the cross-directional tension profiles of the supporting member
used in connection with determining the location of the supporting member.
Detailed description of the invention
[0027] Fig. 1 illustrates a continuously operating reeler, where a paper web W, which is
normally several meters wide and comes from a preceding section of a paper machine
or a finishing apparatus for paper, travels via a reeling nip N1 to a reel R. Said
reeler is a so-called belt reeler in which the reeling nip is formed by means of a
flexible supporting member 1 in the form of an endless loop, such as a belt or a wire.
The supporting member 1 is guided via two guide rolls 2 and 3, at the location of
each of which the run of the member 1 turns to the opposite direction. In the travel
direction of the web the first guide roll 2 can form a "hard nip" with the reel being
started at the initial stage of the reeling in such a manner that the supporting member
1 is in contact with the reel at a point where the member travels supported by the
guide roll 2 on the surface of the roll. The second guide roll 3 can be a driven roll,
i.e. a traction roll, or separate drives can be arranged for both rolls. The web travels
guided by the supporting member 1 onto the machine reel R, which is formed around
a reeling core, i.e. a reel spool 5 rotatable with a center drive of its own. It is
possible for the reel spool 5 to move in the machine direction with respect to the
loop of the supporting member 1, and this is arranged in such a manner that the bearing
housings at the ends of the reel spool that enable the rotation of the reel spool
2 are at both ends of the reel spool supported on carriages, i.e. transfer devices
6 that move on supporting structures 7. In connection with the reeler, there is also
a storage of empty reel spools 5 (not shown), from which the rolls are brought to
the change station at the location of the first guide roll 2 in order to change the
web going to the machine reel R that is becoming full. The reel change takes place
at production speed i.e. the paper web passed at high speed to the full reel is changed
to travel onto a new, empty reel spool brought to the change station.
[0028] In addition to the guide rolls 2 and 3, the endless belt loop 1 is also in contact
with a guide roll 4, which can be provided with a drive or which can be driveless,
and which guides the supporting member 1 from below the loop of the supporting member.
Measuring means 9 measuring variables proportional to the tension of the supporting
member are placed to at least one guide roll 2, 3 and/or 4. The measuring sensor 9
is, for example, a known sensor operating on piezoelectric principle, for example
an EMFi film or PVDF film, which are capable of changing a mechanical input variable,
such as pressure or load into an electric output variable that can be processed by
means of measurement technology. These membrane-like sensors are place in a narrow,
spiral-like band to circle the roll over its entire length, in which case it is ensured
that measurement results are received from the entire length of the roll. The positioning
of the band-like sensor 9 in the guide roll is shown in Fig. 2, in which the roll
presented therein is marked with the reference numeral 2, but said roll can be any
guide roll or traction roll guiding the supporting member.
[0029] In the placement of the sensor 9 the gradient of the rotation angle of the roll of
the spiral in selected as suitable, for example according to the overlap angle of
the belt loop, i.e. the supporting member 1. If necessary, for example in order to
specify the measurement or in case an individual sensor is broken, several sensor
spirals can be installed side by side over the length of the roll. An advantage of
the in a spiral-like manner placed, band-like measuring sensors is that only one measuring
channel per spiral is needed for transferring the measurement data out of the roll,
which may take place wirelessly, for example by means of a telemetry transmitter 10
place in the roll. The measurement data signal is received with a receiver 11. The
receiver in itself can also comprise a data processing unit, where the measurement
signals are processed and the tension profile is determined and the desired parameters
are determined from it or the measurement signal can be transferred from the receiver
11 to the data processing unit 12 for processing. The EMFi film or the PVDF film can
be placed in the roll also by placing individual film strips sequentially in a spiral-like
manner to circle the roll over its entire length. The strip-like measuring sensors
can also be positioned in the guide roll sequentially in the axial direction of the
roll, as shown in Fig. 3. Thus, each sensor strip produces a measurement signal that
represents the pressure exerted on the sensor element at the location of said strip,
and by combining the measurements the tension profile of the supporting member is
produced. The strip-like sensors each require a separate measurement channel. The
guide roll used in the measuring can be any of the guide rolls of Fig. 1. It can therefore
also be a drive roll, where the measuring sensors 9 are placed. It is most advantageous
to use the guide roll located after the reeling nip N1, i.e. roll 3, because, for
example, local bumps in the machine reel are copied to the tension profile of the
belt in the reeling nip and thus appear easily in the tension profile of the supporting
member.
[0030] Determining the cross-directional linear load profile of the reeling nip N1 takes
place in the data processing unit 12 marked in Fig. 1 from the cross-directional tension
profile of the supporting member 1 formed on the basis of the measurements from the
guide roll in a calculatory manner by using transfer functions or, in the simplest
way, by means of scaling factors.
[0031] Fig. 1 also shows a new reel spool 5, which is still in a primary reeling device
8, where it is accelerated to web speed by using the primary reeling device and brought
in contact with a guide roll 2, in which case a so-called hard nip has been formed.
At this stage the variables proportional to the tension of the supporting member,
and thus also the linear load profile of the reeling nip can be attained directly
from the measuring sensor 9 attached to the roll 2. When the reeling progresses and
the diameter of the machine reel R grows, the machine reel R is transferred to the
transfer devices 6 and transferred forward in the machine direction along the supporting
member 1. When the machine reel R has with the growth of the reel transferred away
from nip contact with the guide roll 2, the measurement of variables is performed
at the guide roll 2 or 3 closest to the machine reel R, which roll is equipped with
a measuring sensor, most advantageously at the guide roll 3 that is after the reeling
nip N1 in the machine direction.
[0032] Fig. 4 shows a supporting member 1, whose both guide rolls 2 and 3 are equipped with
measuring means 9 and at least roll 3 is a drive roll. Both rolls 2 and 3 are placed
inside the loop of the supporting member 1. The machine reel R being formed is in
nip contact with the supporting member 1, thus forming a reeling nip N1. One change
in the tension profile of the reeling nip N1, which has transferred to the supporting
member in the reeling nip N1, has been illustrated with a wave form 12. Therefore,
measured variables proportional to the tension are attained from both guide rolls
2 and 3, of which variables are determined tension profiles, whose difference can
be used to determine the tension profile, and further from that, the cross-directional
linear load profile of the reeling nip N1. Since the guide roll 2 is located before
the reeling nip N1 in relation to the direction of movement of the supporting member
according to the travel direction of the web, the measurement results from it and
the tension profile formed from them are used as a reference profile, in which case
the actual tension profile in the reeling nip is determined from the variables measured
after the reeling nip and the difference of the tension profile and reference profile
determined from them. In determining the cross-directional linear load profile of
the reeling nip, it is also possible to use the measurement results from the guide
roll 2 together with the measurement result from the guide roll 4 (not shown) placed
advantageously below the supporting member 1.
[0033] Fig. 5 shows a possibility for measuring variables proportional to the tension of
the supporting member, wherein the measuring sensor 9 is arranged to the supporting
member 1. When the measuring sensors are arranged to the supporting member, they measure
variables proportional to the tension of the supporting member in the reeling nip
N1, i.e. when the measuring sensors 9 arranged to the supporting member 1 and the
reel spool 5 or the machine reel R that is being formed are in contact with each other.
The determination of the tension profile from the measurement results takes place
is the data processing unit, as presented above. It is possible to obtain the cross-directional
linear load profile of the reeling nip directly from these measurements. When point-like
sensors 9 are used in the measurement, they are arranged in a row within suitable
intervals from each other, diagonally across the width of the supporting member 1,
as shown in the figure. When a film-like narrow band sensor 9 is used, it is also
positioned directly in a diagonal position across the width of the supporting member.
This alternative is shown in Fig. 5 as well. The straight line formed both by the
point-like and band-like sensors forms an angle α with the edge of the supporting
member 1. The width of the angle is selected in accordance with the desired measurement
resolution.
[0034] It is possible to provide the supporting member 1 with measuring sensors by positioning
successive strip-like measuring sensors 9 perpendicularly across the width of the
supporting member 1, as shown in Fig. 6. Fig. 6 also shows the positioning of measuring
sensors 9 composed of strain gauges, which is conducted by positioning them successively,
within a fixed distance from each other, and as shown in the preceding alternative,
perpendicularly across the width of the supporting member 1. Strain gauges are able
to separate a tension state in at least two different directions T
1 and T
2, which are illustrated with arrows in Fig. 6.
[0035] The supporting member 1 can also be formed entirely so that it can measure variables
proportional to the tension of the supporting member and/or the cross-directional
linear load profile of the reeling nip N1. The supporting member can, for example,
be formed of several overlapping layers, at least one of which operates as the sensor
performing the measurements. Fig. 7 shows a cross-section of a supporting member 7
formed in layers, which supporting member comprises surface layers 13, between which
there is a sensor layer 14 operating as a sensor. The sensor layer 14 can be, for
example, an EMFi film, which is placed between protective layers. The sensor layer
can naturally be placed elsewhere than between the layers as well.
[0036] It is also possible to determine the tension profile of the supporting member and
further the cross-directional linear load profile of the reeling nip N1 by measuring
variables proportional to the tension of the supporting member 1, which is loaded
with a machine reel growing during continuous reeling, from one guide roll 2, 3, or
4 and by deducting from it the tension profile determined from the variables measured
from the supporting member 1 alone. The measurement of variables of the supporting
member 1 alone takes place with the same guide roll as the measurement of the loaded
supporting member, but without the load of the growing machine reel, i.e. when the
reeling process has for some reason been stopped. During the measurement it is, however,
substantial that the supporting member moves conveyed by the guide rolls. Fig. 8,
which shows determined cross-sectional tension profiles of the supporting member,
illustrates this method. In Fig. 8 curve A shows the cross-sectional tension profile
of the supporting member 1 loaded with a growing machine reel R, which profile is
determined with some variable proportional to the tension or the supporting member,
measured with a guide roll 2, 3 or 4. Curve B shows the tension profile of an unloaded
supporting member 1 determined from the measurements of the same guide roll, and curve
C shows the final tension profile of the growing machine reel R determined from the
difference of curves A and B, i.e. the form profile of the surface. The measurement
of the unloaded supporting member 1 can also be performed by loading the supporting
member 1 with an empty reel spool 5. Since the reel spool is empty, the effect of
the paper web W being reeled does not show in the tension profile B. The measurement
can also be performed by using more than one guide rolls equipped with a measuring
sensor, in which case the determination of the tension profile taking place on the
basis of the measurements is more reliable.
[0037] The cross-directional measurement results of the tension profile of the supporting
member or the cross-directional linear load profile of the reeling nip determined
in connection with the invention can also be utilized in monitoring the supporting
member. This possibility provides and great advantage, because the purchase and assembly
expenses of separate systems are thus avoided and space is saved, because there is
no need to assemble separate apparatuses for monitoring the supporting member. The
measurement results can, for example, be utilized in monitoring the condition of the
supporting member 1, which is illustrated in Fig. 9. For example, the wear of the
supporting member, changes in the porosity or thickness, blockages in the openings
between the wire threads forming the supporting member, and the wire threads breaking
cause changes in the tension profile or in the cross-directional linear load profile
of the reeling nip, where they can be detected. Any of the measurement results of
the variables proportional to the tension of the guide roll 2, 3 or 4, which is in
contact with the supporting member 1 and to which is placed a measuring sensors over
its entire length, and the tension profile of the supporting member attained from
that, or the cross-directional linear load profile measured by measuring sensor attached
to the supporting member in the reeling nip can be used in monitoring the condition
of the supporting member. The measurement of the variables proportional to the tension
of the supporting member performed with the guide rolls for monitoring the condition
of the supporting member are performed when the reeling nip N1 is open, i.e. when
the reel spool 5 or the growing machine reel R are not in contact with the supporting
member 1. In Fig. 9, curve D represents a tension profile formed of a supporting member
9 in a good condition on the basis of measurements or a cross-directional linear load
profile of the reeling nip and curve E represents the tension/nip pressure profile
curve of a supporting member that is worn or has experienced changes, wherein a change
in the tension/nip pressure profile, which is marked in the figure with an arrow,
can be detected. In identifying a change, it is possible to apply, for example, a
neural network, which learns to identify the effect of the wear or failure of the
supporting member. Processing the measuring results and determining the condition
monitoring parameters of the supporting member takes place in the data processing
unit.
[0038] One possibility to utilize the measurement results of the tension profile of the
supporting member determined in connection with the invention or the cross-directional
linear load profile of the reeling nip is to monitor the location of the edges of
the supporting member. The measurement results of the variables proportional to the
tension of any guide roll 2, 3 or 4, which is in contact with the supporting member
1 and in which is placed a measuring sensor over the entire length of the roll, can
be used in a manner known as such from the patent publication
FI-20012528 for monitoring the position of the edge of the supporting member in the longitudinal
direction of the guide roll. The measurement can be performed when the reeling nip
N1 is either open or closed. The cross-directional linear load profile measured with
measuring sensors attached to the supporting member in the reeling nip can be used
for this purpose. In Fig. 10, curve F shows the CD-profile of the machine-directional
tension determined from the supporting member 1 on the basis of the measurements.
The dashed lines G and G' illustrate the location of the edges of the supporting member
1. If the supporting member travels over the allowed edge limits, it is easily and
quickly detected from the profile and correction procedures can be performed. The
location of the edges of the supporting member is also possible to monitor by assembling
separate, short sensor spirals at both ends of the guide roll, which monitor the location
of the edges of the supporting member both at their own end of the roll, but do not
extend from one end of the guide roll to the other. It is also possible to place to
the same guide roll both a sensor spiral extending over the entire length of the guide
roll and short sensor rolls placed in the ends, in which case it is possible to determine
the tension profile data and the location data of its edges from the measurements
attained from the same guide roll.
[0039] The invention is not intended to be limited to the embodiments presented as examples
above, but the invention is intended to be applied widely within the scope of the
appended claims. The supporting member 1 can, for example, be supported by more guide
rolls than what is presented above in the description. Further, measuring sensors
can be placed to all guide rolls or a part of the rolls can be without a measuring
sensor, in which case they operate only as rolls guiding the belt loop. The invention
can be applied in reelers of machines manufacturing paper, paperboard, tissue or a
similar web-like product and in finishing devices connected to them.
1. A method in a reeler, wherein a reeling nip (N1) is formed by a reeling core (5) or
a growing machine reel (R) and at least one loop of an endless supporting member (1)
that is substantially continuous in the axial direction of the reeling core (5), characterized in that the cross-directional linear load profile of the reeling nip (N1) is measured by
means of at least one measuring means (9) that is arranged to the supporting member
(1).
2. The method according to claim 1, characterized in that the measuring means (9) comprise of at least one narrow, strip-like sensor.
3. The method according to claim 1, characterized in that the measuring means (9) comprise of several separate sensors.
4. The method according to claim 1, characterized in that the measuring means (9) are formed of one of the following: a piezoelectric sensor,
a piezocrystal sensor, a capacitive, resistive, inductive sensor, a load-measuring
sensor and a force-measuring sensor.
5. The method according to claim 2 or 3, characterized in that the measuring means (9) circle the guide roll (2, 3, 4) in a spiral-like manner substantially
over its entire length.
6. The method according to claim 3, characterized in that the measuring means (9) extend substantially over the entire length of the guide
roll (2, 3, 4) straight in its axial direction.
7. The method according to claim 1, characterized in that the measuring means extend diagonally in a straight line across the width of the
supporting member (1), which line forms an angle α with the edge of the supporting
member (1).
8. The method according to claim 1, characterized in that the measuring means (9) extend perpendicularly across the width of the supporting
member (1).
9. The method according to claim 1, characterized in that the measuring means (9) are arranged inside the structure of the supporting member
(1).
10. The method according to claim 1, characterized in that the cross-directional linear load profile of the reeling nip (N1) is measured repeatedly
and by means of it, one of the following is monitored: the condition of the supporting
member (1) and the position of the supporting member (1) in the longitudinal direction
of the guide roll (2, 3,4).
11. The method according to claim 1, characterized in that the cross-directional linear load profile of the reeling nip (N1) is measured repeatedly
and by means of it, one of the following is monitored: the average tension of the
endless supporting member (1) and the diameter profile of the growing machine roll
(R) forming in the reeling.
12. The method according to claim 1, characterized in that the width of the endless supporting member (1) is substantially the same as the width
of the web (W) to be reeled.
13. A reeler, wherein a reeling nip (N1) is formed by a reeling core (5) or a growing
machine reel (R) and at least one loop of an endless supporting member (1) that is
substantially continuous in the axial direction of the reeling core (5), characterized in that at least one measuring means (9) is arranged to the supporting member in order to
measure the cross-directional linear load profile of the reeling nip (N1).
14. The reeler according to claim 13, characterized in that the measuring means (9) comprise of at least one narrow, strip-like sensor.
15. The reeler according to claim 13, characterized in that the measuring means (9) comprise of several separate sensors.
16. The reeler according to claim 13, characterized in that the measuring means (9) are formed of one of the following: a piezoelectric sensor,
a piezocrystal sensor, a capacitive, resistive, inductive sensor, a load-measuring
sensor and a force-measuring sensor.
17. The reeler according to claim 14 or 15, characterized in that the measuring means (9) are arranged to circle the guide roll (2, 3, 4) in a spiral-like
manner substantially over its entire length.
18. The reeler according to claim 15, characterized in that the measuring means (9) are arranged to extend substantially over the entire length
of the guide roll (2, 3, 4) straight in its axial direction.
19. The reeler according to claim 13, characterized in that the measuring means (9) are arranged in a straight line, which extends diagonally
across the width of the supporting member (1), and forms an angle α with the edge
of the supporting member (1).
20. The reeler according to claim 13, characterized in that the measuring means (9) are arranged perpendicularly across the width of the supporting
member (1).
21. The reeler according to claim 13, characterized in that the measuring means (9) are arranged inside the structure of the supporting member
(1).
22. The reeler according to claim 13, characterized in that the means (12) are further arranged to monitor one of the following on the basis
of the cross-sectional linear load profile of the reeling nip (N1) measured repeatedly:
the condition of the endless supporting member and the position of the endless supporting
member (1) in the longitudinal direction of the guide roll (2, 3, 4).
23. The reeler according to claim 13, characterized in that the means (12) are further arranged to determine one of the following on the basis
of the cross-sectional linear load profile of the reeling nip (N1) measured repeatedly:
the average tension of the endless supporting member (1) and the diameter profile
of the growing machine roll (R) forming in the reeling.
24. The reeler according to claim 13, characterized in that the width of the endless supporting member (1) is substantially the same as the width
of the web (W) being reeled.
1. Verfahren in einer Wickelvorrichtung, wobei ein Wickelspalt (N1) durch einen Wickelkern
(5) oder eine wachsende Maschinenrolle (R) und mindestens eine Schleife eines endlosen
Tragelements (1) gebildet wird, die im Wesentlichen in Axialrichtung des Wickelkerns
(5) durchgehend ist, dadurch gekennzeichnet, dass das quergerichtete Linienlastprofil des Wickelspalts (N1) mit Hilfe von mindestens
einem Messmittel (9), das am Tragelement (1) angeordnet ist, gemessen wird.
2. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) mindestens einen schmalen streifenartigen Sensor enthält
bzw. enthalten.
3. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) mehrere getrennte Sensoren enthält bzw. enthalten.
4. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) aus einem der folgenden gebildet ist bzw. sind: ein piezoelektrischer
Sensor, ein Piezokristallsensor, ein kapazitiver Sensor, ein Widerstandssensor, ein
induktiver Sensor, ein Lastmesssensor und ein Kraftmesssensor.
5. Verfahren gemäß Anspruch 2 oder 3, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) die Führungswalze (2, 3, 4) in einer schraubenförmigen
Weise im Wesentlichen über ihre gesamte Länge umläuft bzw. umlaufen.
6. Verfahren gemäß Anspruch 3, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) sich im Wesentlichen über die gesamte Länge der Führungswalze
(2, 3, 4) gerade in ihrer axialen Richtung erstreckt bzw. erstrecken.
7. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel sich diagonal in einer geraden Linie über die Breite des
Tragelementes (1) erstreckt bzw. erstrecken, welche Linie einen Winkel αmit dem Rand
des Tragelements (1) bildet.
8. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) sich im rechten Winkel über die Breite des Tragelements
(1) erstreckt bzw. erstrecken.
9. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) innerhalb der Struktur des Tragelements (1) angeordnet
ist bzw. sind.
10. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das quergerichtete Linienlastprofil des Wickelspalts (N1) wiederholt gemessen wird
und mit Hilfe davon eines der folgenden überwacht wird: der Zustand des Tragelements
(1) und die Position des Tragelements (1) in der Längsrichtung der Führungswalze (2,
3, 4).
11. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass das quergerichtete Linienlastprofil des Wickelspalts (N1) wiederholt gemessen wird
und mit Hilfe davon eines der folgenden überwacht wird: die mittlere Spannung des
endlosen Tragelements (1) und das Durchmesserprofil der wachsenden Maschinenrolle
(R), die sich beim Wickeln bildet.
12. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass die Breite des endlosen Tragelements (1) im Wesentlichen gleich der Breite der aufzuwickelnden
Bahn (W) ist.
13. Wickelvorrichtung, in der ein Wickelspalt (N1) durch einen Wickelkern (5) oder eine
wachsende Maschinenrolle (R) und mindestens einer Schleife eines endlosen Tragelements
(1) gebildet ist, die im Wesentlichen in axialer Richtung des Wickelkerns (5) durchgehend
ist, dadurch gekennzeichnet, dass mindestens ein Messmittel (9) am Tragelement angeordnet ist, um das quergerichtete
Linienlastprofil des Wickelspalts (N1) zu messen.
14. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) mindestens einen schmalen streifenartigen Sensor enthält
bzw. enthalten.
15. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) mehrere getrennte Sensoren enthält bzw. enthalten.
16. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) aus einem der folgenden gebildet ist: ein piezoelektischer
Sensor, ein Piezokristallsensor, ein kapazitiver Sensor, ein Widerstandssensor, ein
induktiver Sensor, ein Lastmesssensor und ein Kraftmesssensor.
17. Wickelvorrichtung gemäß Anspruch 14 oder 15, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) ausgestaltet ist bzw. sind, um die Führungswalze (2,
3, 4) in einer schraubenförmigen Weise im Wesentlichen über ihre gesamte Länge zu
umkreisen.
18. Wickelvorrichtung gemäß Anspruch 15, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) ausgestaltet ist bzw. sind, um sich im Wesentlichen über
die gesamte Länge der Führungswalze (2, 3, 4) gerade in deren axialer Richtung zu
erstrecken.
19. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) in einer geraden Linie angeordnet ist bzw. sind, die
sich diagonal über die Breite des Tragelements (1) erstreckt bzw. erstrecken und mit
dem Rand des Tragelements (1) einen Winkel α bildet bzw. bilden.
20. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) im rechten Winkel über die Breite des Tragelements (1)
angeordnet ist bzw. sind.
21. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Messmittel (9) innerhalb der Struktur des Tragelements angeordnet ist
bzw. sind.
22. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Mittel (12) ferner angeordnet ist bzw. sind, um auf Basis des wiederholt
gemessenen quergerichteten Linienlastprofils des Wickelspalts (N1) eines der folgenden
überwacht wird: der Zustand des endlosen Tragelements und die Position des endlosen
Tragelements (1) in der Längsrichtung der Führungswalze (2, 3, 4).
23. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass das bzw. die Mittel (12) ferner angeordnet ist bzw. sind, um auf Basis des wiederholt
gemessenen quergerichteten Linienlastprofils des Wickelspalts (N1) eines der folgenden
zu bestimmen: die mittlere Spannung des endlosen Tragelements (1) und das Durchmesserprofil
der sich beim Wickeln bildenden wachsenden Maschinenrolle (R).
24. Wickelvorrichtung gemäß Anspruch 13, dadurch gekennzeichnet, dass die Breite des endlosen Tragelements (1) im Wesentlichen gleich der Breite der Bahn
(W), die gewickelt wird, ist.
1. Procédé dans une enrouleuse, dans lequel une ligne de contact d'enroulement (N1) est
formée par un noyau d'enroulement (5) ou une bobine croissante (R) de machine et au
moins une boucle d'un élément support sans fin (1) qui est sensiblement continu dans
le sens axial du noyau d'enroulement (5), caractérisé en ce que le profil de charge linéaire transversal de la ligne de contact d'enroulement (N1)
est mesuré au moyen d'au moins un moyen de mesure (9) qui est agencé sur l'élément
support (1).
2. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure (9) est composé d'au moins un capteur étroit de type bande.
3. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure (9) est composé de plusieurs capteurs séparés.
4. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure (9) est formé de l'un des suivants : un capteur piézoélectrique,
un capteur à piézo-cristal, un capteur capacitif, résistif, ou inductif, un capteur
de mesure de charge et un capteur de mesure de force.
5. Procédé selon la revendication 2 ou 3, caractérisé en ce que le moyen de mesure (9) encercle le cylindre de guidage (2, 3, 4) d'une manière de
type en spirale sensiblement sur la totalité de sa longueur.
6. Procédé selon la revendication 3, caractérisé en ce que le moyen de mesure (9) s'étend sensiblement sur la totalité de la longueur du cylindre
de guidage (2, 3, 4) en ligne droite dans son sens axial.
7. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure s'étend diagonalement selon une ligne droite sur la largeur de
l'élément support (1), laquelle ligne forme un angle α avec le bord de l'élément support
(1).
8. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure (9) s'étend perpendiculairement sur la largeur de l'élément support
(1).
9. Procédé selon la revendication 1, caractérisé en ce que le moyen de mesure (9) est agencé à l'intérieur de la structure de l'élément support
(1).
10. Procédé selon la revendication 1, caractérisé en ce que le profil de charge linéaire transversal de la ligne de contact d'enroulement (N1)
est mesuré de façon répétée et au moyen de celui-ci, l'un des suivants est surveillé
: l'état de l'élément support (1) et la position de l'élément support (1) dans le
sens longitudinal du cylindre de guidage (2, 3, 4).
11. Procédé selon la revendication 1, caractérisé en ce que le profil de charge linéaire transversal de la ligne de contact d'enroulement (N1)
est mesuré de façon répétée et au moyen de celui-ci, l'un des suivants est surveillé
: la tension moyenne de l'élément support sans fin (1) et le profil de diamètre de
la bobine croissante (R) de machine se formant lors de l'enroulement.
12. Procédé selon la revendication 1, caractérisé en ce que la largeur de l'élément support sans fin (1) est sensiblement la même que la largeur
de la bande (W) devant être enroulée.
13. Enrouleuse, dans laquelle une ligne de contact d'enroulement (N1) est formée par un
noyau d'enroulement (5) ou une bobine croissante (R) de machine et au moins une boucle
d'un élément support sans fin (1) qui est sensiblement continu dans le sens axial
du noyau d'enroulement (5), caractérisée en ce qu'au moins un moyen de mesure (9) est agencé sur l'élément support afin de mesurer le
profil de charge linéaire transversal de la ligne de contact d'enroulement (N1).
14. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est composé d'au moins un capteur étroit de type bande.
15. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est composé de plusieurs capteurs séparés.
16. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est formé de l'un des suivants : un capteur piézoélectrique,
un capteur à piézo-cristal, un capteur capacitif, résistif, ou inductif, un capteur
de mesure de charge et un capteur de mesure de force.
17. Enrouleuse selon la revendication 14 ou 15, caractérisée en ce que le moyen de mesure (9) est agencé pour encercler le cylindre de guidage (2, 3, 4)
d'une manière de type en spirale sensiblement sur la totalité de sa longueur.
18. Enrouleuse selon la revendication 15, caractérisée en ce que le moyen de mesure (9) est agencé pour s'étendre sensiblement sur la totalité de
la longueur du cylindre de guidage (2, 3, 4) en ligne droite dans son sens axial.
19. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est agencé selon une ligne droite, qui s'étend diagonalement
sur la largeur de l'élément support (1), et forme un angle α avec le bord de l'élément
support (1).
20. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est agencé perpendiculairement sur la largeur de l'élément
support (1).
21. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (9) est agencé à l'intérieur de la structure de l'élément support
(1).
22. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (12) est en outre agencé pour surveiller l'un des suivants sur
la base du profil de charge linéaire transversal de la ligne de contact d'enroulement
(N1) mesuré de façon répétée : l'état de l'élément support sans fin et la position
de l'élément support sans fin (1) dans le sens longitudinal du cylindre de guidage
(2, 3, 4).
23. Enrouleuse selon la revendication 13, caractérisée en ce que le moyen de mesure (12) est en outre agencé pour déterminer l'un des suivants sur
la base du profil de charge linéaire transversal de la ligne de contact d'enroulement
(N1) mesuré de façon répétée : la tension moyenne de l'élément support sans fin (1)
et le profil de diamètre de la bobine croissante (R) de machine se formant lors de
l'enroulement.
24. Enrouleuse selon la revendication 13, caractérisée en ce que la largeur de l'élément support sans fin (1) est sensiblement la même que la largeur
de la bande (W) étant enroulée.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description