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EP 1 991 726 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: 20.02.2007 |
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International Patent Classification (IPC):
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International application number: |
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PCT/IB2007/000460 |
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International publication number: |
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WO 2007/096765 (30.08.2007 Gazette 2007/35) |
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IMPROVED DEVICE FOR FEEDING THREAD OR YARN TO A TEXTILE MACHINE AND A METHOD FOR IMPLEMENTING
THE FEED
VERBESSERTE VORRICHTUNG ZUR BESCHICKUNG EINER TEXTILMASCHINE MIT EINEM FADEN ODER
GARN SOWIE BESCHICKUNGSVERFAHREN
DISPOSITIF AMELIORE POUR AMENER DU FIL A UNE MACHINE TEXTILE ET PROCEDE POUR METTRE
EN OEUVRE CETTE ALIMENTATION
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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 LV MC NL PL PT RO SE
SI SK TR |
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Priority: |
21.02.2006 IT MI20060311
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Date of publication of application: |
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19.11.2008 Bulletin 2008/47 |
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Proprietor: B.T.S.R. International S.p.A. |
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21057 Olgiate Olona (Varese) (IT) |
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Inventor: |
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- BAREA, Tiziano
I-21052 Busto Arsizio (Varese) (IT)
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Representative: Ripamonti, Enrico et al |
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Giambrocono & C. S.p.A.,
Via Rosolino Pilo, 19/B 20129 Milano 20129 Milano (IT) |
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References cited: :
WO-A-93/23595 GB-A- 2 128 213 US-A- 5 509 450
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DE-A1- 1 937 059 US-A- 4 832 270 US-A- 5 740 974
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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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[0001] The present invention relates to a device for feeding thread or yarn to a textile
machine in accordance with the introduction to the main claim. The invention also
relates to a method for implementing the feed.
[0002] Two main types of device are known for feeding a thread or yarn to a textile machine:
a first device is the so-called accumulation or negative device, the second device
being a continuous (positive) feed system without thread accumulation, and enabling
the thread to be fed to the textile machine at constant tension or quantity.
[0003] The first known device is, for example, described in
DE1937059; it comprises a cylindrical element or rotary accumulator driven by its own motor
and on which the thread to be fed to the textile machine is wound.
[0004] The thread is autonomously withdrawn from the machine which unwinds it from the above
cylindrical element. In other words, this cylindrical element or accumulator serves
as a thread reservoir and unloads more or less depending on the machine particular
production moment.
[0005] This thread passes successively through a tensioning member (annular comb, annular
brush or the like), the pressure of which (adjusted to fixed values or manually by
interchangeable tensioning members) on the cylindrical element or accumulator transmits
an uncontrolled and unregulated tension (not adjustable continuously on the basis
of that stage of the textile process underway) to the thread via a closed regulator
ring, to maintain it constant with time; this first device consequently operates under
open loop. The tension is however maintained within an acceptable range of values
related to the fact that the thread has been accumulated and unwinds from an accumulation
drum or accumulator of predefined diameter.
[0006] Moreover, as the tensioning member wears, the applied tension varies to an extent
which cannot be compensated by the accumulator or drum and requires a new adjustment
of the position of this member or its complete replacement.
[0007] In any event, the variation in the tension of the yarn which accumulates on the drum
(linked mainly to the variation in the spool diameter from full to empty or to simply
changing the spool, this variation affecting the tension of the thread unwinding from
it) varies with time and cannot be entirely compensated. In this respect, a low tension
of the thread entering the accumulator (present with full spool) leads to deposition
of turns on the drum with low tension (slacker turns and thread easier to unwind),
whereas a high thread tension (present with empty spool) leads to tighter turn deposition
and hence greater difficulty in thread unwinding. This influences the tension of the
thread directed to the textile machine and prevents it from being able to be constant
with time. These drawbacks are more evident the higher the elasticity of the thread
used.
[0008] Said first device enables the thread to be fed to the textile machine without undergoing
jerking during its unwinding from the usual bobbin or spool located upstream of the
rotary cylindrical element (such jerking could break the thread wound compactly on
itself or could cause processing defects). However with this device it is impossible
to maintain constant feed tension as it is the machine itself which withdraws the
thread from the accumulator in known manner (for example by shuttle, water jet, needles,
etc.).
[0009] Moreover, this known device is able to maintain correct thread feed only if a low
thread tension is required (for example 1 g or 10 g). Again, if the type of yarn processed
is changed, the type of tensioning member (for example annular brush) has to be replaced
by one compatible with the fed yarn and the tensions required.
[0010] In addition, the yarn cannot be fed under high tension (for example 50 or 100 g),
neither can the tension of the fed yarn be varied on the basis of the stage of manufacture
during the textile processing cycle (for example cuff; leg-foot of a stocking).
[0011] A tensioning member in direct contact with the thread can damage and wear both the
thread and itself very rapidly.
[0012] Control means (for example of photoelectric cell type) are present to evaluate the
accumulation of thread on said rotary element, hence enabling its automatic refilling,
vibration means also being present to separate the accumulated turns and to facilitate
thread unwinding from this element.
[0013] A device of the stated type is described in particular in
US5509450 which forms the introduction to the main claim. This device is arranged to feed thread
to a textile machine with which it cooperates in strict synchronism and comprises
a thread accumulation drum which is fixed but on which a winder mechanism moves, driven
by guide means. A gripper element positioned radially to the front of the fixed drum
is driven by its own guide means and is associated with a shaft coaxial to the geometrical
axis of the drum. The guide means for the winder mechanism and for the gripper element
(cooperating with the thread) are positioned consecutively in the device. A thread
retainer element is mainly described rotating relative to the drum, with which it
is in point contact, to control the velocity profile of the thread in the various
stages of insertion of the thread into a textile machine (weaving machine) so as to
determine this insertion position
[0014] This device has the same aforedescribed limits of similar accumulation devices of
open loop operation.
[0015] Other solutions equivalent to those described in the aforesaid prior texts and with
the same drawbacks are reported in
US5740974, in
WO93/23595 and
US4832270.
[0016] In contrast, continuous feed devices or positive feed devices are interposed between
the bobbin from which the thread is unwound and the textile machine, and comprise
means for example to measure the thread tension and if necessary to intervene on this
latter to adjust this tension and maintain it constant. In the case under examination
these devices therefore present closed loop tension regulation means. However the
devices under examination are influenced by system inertia in response to the request
for yarn by the machine, in particular when this operates discontinuously. It can
hence happen that because of this inertia, a sudden request for thread gives rise
to a tension peak in the thread while cooperating with such feed devices, with the
result that a defect in the weaving process or a thread breakage occurs, with obvious
drawbacks with regard to the operability of the textile machine.
[0017] An object of the present invention is to provide a device and method for feeding
thread or yarn to a textile machine which represent an improvement compared with said
known feed devices operating in accordance with the aforesaid types.
[0018] A particular object of the present invention is to provide a device and method of
the stated type which combine in themselves both the aforesaid negative and positive
types of thread feed, to overcome the drawbacks of the individual similar known devices
and methods of the state of the art.
[0019] Another object is to provide an improved device and method of the stated type which
enable correct yarn feed to a discontinuously operating textile machine by which thread
breakage is prevented, while at the same time maintaining constant thread tension
and rapid response of the feed system following each stoppage and restart of the machine
or sudden variation in thread or yarn absorption.
[0020] Another object is to provide a device which in addition to feeding at constant tension
also enables take-up at constant tension and accumulation of the thread taken up so
that it can be returned when again withdrawn by the textile machine.
[0021] A further object is to provide a method for feeding thread or yarn to a textile machine
which uses the combined and controlled action of two separate actuators to multiply
the acceleration and deceleration performance of the aforesaid device during this
feed, in order to maintain the yarn tension constant.
[0022] A further object is to provide a device of the stated type which is of small dimensions
enabling it to be easily positioned on a textile machine.
[0023] A further object is to provide a device and method for feeding a thread at constant
tension which enables it to be freely unwound from an accumulation element in the
case of sudden thread withdrawal by the textile machine without appreciable tension
variation occurring such as to negatively affect the quality of the product obtained
by said machine.
[0024] These and other objects which will be evident to the expert of the art are attained
by a feed device and method in accordance with the accompanying claims.
[0025] The present invention will be more apparent from the following drawings, which are
provided by way of non-limiting example and in which:
Figure 1 is a perspective view of a device according to the invention;
Figure 2 is a view of the device of Figure 1 from above;
Figure 3 is a front view of the device of Figure 1;
Figure 4 is a section on the line 4-4 of Figure 3; and
Figure 5 is a block scheme of the device of the invention.
[0026] With reference to said figures, the device of the invention comprises a casing 1
defined by two portions 2, 3 removably fixed together by fixing screws 4. Both portions
are hollow, at 5 and 6 respectively. The cavity 6 of the portion 3 partially contains
an electric motor 9 (for example of brushless type) projecting from said cavity 6
to the front of the casing 1. Keyed onto an exit shaft 8 of the electric motor 9 there
is a rotary element 7 positioned above that motor part 9 projecting from said cavity
6 and rotating above the motor about a longitudinal axis W of the casing 1.
[0027] The element 7 presents an outer advantageously grooved surface 11 for supporting
a thread or yarn 12 unwinding from a spool or bobbin 13 represented schematically
in Figure 1. The thread 12 reaches the surface 11 via a thread guide 15 associated
with the casing 1. A turn separator member 7K of adjustable inclination is present
to space the turns. This adjustment enables the inclination of the member 7K to the
element 7 to be modified by acting on a screw 7F present on the casing 1.
[0028] In this manner, the element 7 acts as a yarn accumulator. In this respect, a large
number of yarn turns can be accumulated on the surface 11, the number of these turns
being controlled and programmable, for example in the manner described hereinafter.
[0029] The motor 9 and its emerging shaft 8 are hollow, within them there being positioned
another shaft 17 driven by a second electric motor 18 located in the cavity 5 of the
portion 2 of the casing 1. The drive shaft 17 cooperates with a rotary element 20
positioned to the front of the casing 1 beyond the element or accumulator 7 along
the path along which the thread moves towards a textile machine (not shown). The rotary
member 20 is therefore independent of the accumulator 7 and can move both idly and
as a result of the activation of the motor 18.
[0030] Because of the particular form of the motor 9 and shaft 8, a particularly compact
device is obtained although enabling two (possibly identical) actuators to be included
performing differentiated operations; this represents a considerable advantage compared
with known solutions, both from the industrial viewpoint (cost reduction) and with
regard to the positioning of the device in a textile machine: if this should require
a considerable number of devices 1, these can be easily positioned in suitable locations
for their use without this involving particular space problems. The rotary element
20 is preferably in the shape of a solid of rotation, as a spherical or conical cap
or paraboloid or ellipsoid tapering in the direction (indicated by the arrow G of
Figure 1) of the thread 12 directed to the textile machine; this element 20 presents
an outer free surface 21 along which the thread 12 originating from the accumulator
7 slides freely, the thread thus being able to reach a thread guide 23 and from there
be directed to the textile machine. The fact that the thread can move freely on the
outer surface of the element 20 enables the thread to freely unwind from the accumulator
7 in the case of sudden absorption of thread by the textile machine, even though the
element 20 is under rotary movement. Moreover because of the free movement of the
thread on the surface 21 any knotting or thickening of the thread does not cause extra
tension in the thread moving towards the textile machine, with consequent possible
breakage or possible production of a defective article. However a large-dimension
aperture or eyelet 21A can be provided in the rotary element 20, opening in proximity
to an edge thereof and through which the thread passes. The purpose of this is to
enable a predetermined quantity of thread to be fed to the textile machine.
[0031] The thread guide 23 is defined by a ring 25 formed in a portion 26 of a bent angle
bracket 27 fixed to the casing 1. Preferably and advantageously the portion 26 of
the angle bracket 27 supports a tension sensor 30 of known type connected to a yarn
feed control unit 200 (see Figures 4 and 5) which also controls the operation of the
electric motors 9 and 18 and controls the accumulation of the thread on the element
7. This control unit can be advantageously inserted into the device casing 1, as shown
in Figure 4.
[0032] The device of the invention hence operates as a feed device with thread accumulation
as a result of using the element 7 and as a positive constant-tension thread feed
device by virtue of the tension control provided by the elements 20 and 7 controlled
by the unit 200 on the basis of the tension measured by the sensor 30 and the desired
value programmed for the precise processing stage which the machine is carrying out
(closed loop regulation). By virtue of its rotation, which is independent but combined
with the element 7, the element 20 enables the acceleration and deceleration performance
of the device to be multiplied, to hence maintain the tension of the thread 12 fed
to the textile machine constant. The element 20 alone can if necessary take up this
thread when the textile machine is of intermittent operation type (reciprocating motion)
and hence subjected to thread withdrawal stages alternating with withdrawal stoppage
stages with possible return of part of the fed thread. In this case, as explained
hereinafter, the rotary member 20 enables the thread already fed to the textile machine
(during the stoppage stage) to be taken up and be rewound on the element 7. Even if
the element 20 does not possess an eyelet and presents a surface which is smooth,
undulated or with brush fibres, the thread would still be taken up by the element
20 because of the friction exerted between it (its profile or the fibres associated
with it) and said thread without the need for any fixed retention element (such as
the eyelet 21A) for the thread.
[0033] The element 20 is always able to be controlled by the motor 18 or can remain free
to rotate idly about said motor in order, for example, not to oppose a sudden request
for yarn by the machine.
[0034] By virtue of the device, the machine on which it is mounted can be made to vary the
type of operation on the basis of the thread being processed and the actual process
itself, without having to modify or replace the feed device for the thread to be processed.
In this respect, if the machine operates continuously on one thread, the only device
function utilized is substantially that of feeder with constant thread accumulation
(number of thread turns present thereon constant with time), the thread which unwinds
from the spool 13 and directed towards the element 7 being wound on this latter and
being constantly fed at constant tension to the textile machine under the said closed
loop tension regulation. In this case, the element 20, controlled by the unit 200
and rotating in the same direction as the accumulation element 7 at a velocity equal
to or less than that of this latter, allows the thread to slide along its surface
(if said element 20 is without an eyelet, the preferred solution).
[0035] If instead a different process is carried out on the machine and the machine operates
discontinuously, both the rotary elements 7 and 20 intervene actively (independently
of each other, but combined) during thread feed. In this respect, while the textile
machine withdraws the thread 12 from the element 7 which rotates driven by its motor
9 and enables thread feed at constant tension (controlled by the sensor 30) to be
maintained, the motor 18 which operates the element 20 rotates in the same direction
as the element 7 and the thread can move freely on the surface 21 of the element 20
towards the textile machine.
[0036] In the cased of a sudden thread absorption increase, the motor 9 which drives the
element or accumulator 7 accelerates whereas the thread continues to unwind freely
along the surface 21 of the element 20. As the thread requirement by the machine can
be so high as to exceed the acceleration dynamics of the motor 9, the machine can
also withdraw part of the supply accumulated on the element 7. This happens without
impediment and without increase in thread tension as the thread is free to slide along
the surface 21 of the rotating element 20.
[0037] The motor 9 then continues its operation even when the sudden thread absorption ceases,
in order to recover and re-establish the thread supply accumulated on the element
7.
[0038] It should be noted that the increase in acceleration of the motor 9 is determined
by the closed control loop defined by the sensor 30, the unit 200 and the motor itself.
Moreover, as the motor 9 accelerates the motor 18 also accelerates proportionally
in consequence.
[0039] In the case of a sudden absorption decrease, the motor decelerates or stops while
the element 20, already rotating and maintained moving in the previous direction or
rotation equal to that of the element 7, rewinds the thread onto the element 7 itself,
enabling high deceleration capacity in the thread feed to the machine by taking up
any excess thread overfeed.
[0040] In other words, when the textile machine stops withdrawing thread from the element
7, the motor 9 is halted wile the motor 18 continues its rotation to rotate the element
20 about the axis W in the same direction as that of the previous rotation of the
element 7. The element 20 consequently takes up thread from the textile machine by
virtue of the friction exerted between it and said element (its profile or the fibres
associated with it) without any fixed thread retention element (such as the eyelet
21A). The element 20 deposits this thread on the element 7 by rewinding it on this
latter and maintaining the thread take-up tension at a constant programmed value,
equal to or different from the programmed working tension at which the thread is fed.
The number of new turns wound on this element is known from the number of revolutions
of the element 20 about the axis W, for example known using usual control elements
for the rotation of the motor 18 (Hall sensors, encoders, etc.).
[0041] When the machine again withdraws thread 12, with the motor 9 still at rest this machine
again unwinds thread from the element 7, this thread being able to unwind freely and
undisturbed by sliding on the surface 21 of the element 20. This happens in a like
manner to the previously described case of sudden increase in thread absorption.
[0042] Alternatively, the rotation of the motor 18 can be reversed to hence rotate the element
20 in the opposite direction to that prior to take-up, so allowing the thread previously
withdrawn and accumulated (in known quantity as the number of wound turns is known)
on the element 7 to be immediately returned at constant tension to said machine. On
termination of thread take-up from the textile machine, the motor 9 is restarted to
again feed the thread accumulated on the element 7 to the textile machine at constant
tension, while at the same time again removing further thread from the spool 13 to
maintain the number of turns accumulated on its surface 11 constant.
[0043] This method of operation prevents jerking of the thread which could create processing
defects or break it on resuming operation of the textile machine. As an alternative
to that described, when yarn withdrawal again starts, the motor 9 is immediately rotated,
although at a speed slower than the feed speed, in the thread unwinding direction
in order to "softly" resume accumulation of thread withdrawn from the spool 13 onto
it. Feed of the thread to the textile machine is hence facilitated, this improving
the response speed of the device of the invention.
[0044] In the case of a discontinuously operating machine, the invention can prevent thread
accumulation on the machine when it stops withdrawing thread from the spool, so dispensing
with any mechanical, electromechanical or pneumatic thread take-up members currently
used on machines, such as seamless and straight bar hosiery machines operating discontinuously.
In this respect, as stated the element 20 takes up the thread by accumulating it on
the element 7. Hence a surplus of thread is formed on said element 7, so facilitating
restart of the textile machine on restoring production of the article by maintaining
the tension constant both during feed and during take-up of the yarn, hence without
subjecting the thread to excessive tension which could cause a thread processing defect
or breakage.
[0045] The invention also prevents thread accumulating at the textile machine following
a sudden deceleration thereof, even if the element 20 is provided with an eyelet 21A.
Such deceleration is sensed (in known manner) by the control unit 200 via the tension
measurement effected by the sensor 30 of the feed device connected or applied to the
machine, this unit braking the operation of the motor 9 and rotating the element 20
in the take-up direction by operating the motor 18. When the machine again accelerates,
the motor 18 is rotated in the opposite direction, so unloading the thread accumulated
by the element 7 by passing through the eyelet 21A of the element 20, and enabling
the textile machine to take from this later the thread accumulated thereon.
[0046] Again if the element 20 is provided with an eyelet 21A, its intervention is very
rapid as it acts on a thread presenting practically zero resistance (to traction by
said element) both when the thread is taken up from the textile machine and returned
freely to the feeder, and when it unwinds it from the element 7 (where it is accumulated
by having been withdrawn from the machine or from the spool 13). Because of this absence
of effort in withdrawing the thread from the element 7 by the machine, said withdrawal
can also be achieved by simple "friction" between the thread and the surface 21 of
the element 20 when provided with an eyelet 21A. The absence of effort hence enables
the device performance to be not merely a simple addition to combine the effects of
the two motors, but to be a multiplication of the performances as the motor 18 operates
without effort.
[0047] It should be noted that, as stated, the device enables a constant number of turns
to be maintained on the element 7. This is achieved totally automatically in the following
manner.
[0048] The number of turns on the element 7 is maintained constant by continuously recognizing
(by the control unit 200 of the device) the number of rotations made by said element
7 about the axis W (by recognizing the number of rotations of the motor 9, for example
by Hall sensors) and by the element 20 (by recognizing the number of rotations of
its motor 18, for example by Hall sensors). The number of rotations of the motor 9
always increases the turns accumulated, whereas the number of rotations of the motor
18 can either increase or decrease this count. In fact, based on this count, the control
unit 200 of the device can always know (directly from the rotations of the motor if
the motor 18 and the element 20 are at rest, or by the algebraic sum if the motor
9 and the motor 18 operate in opposite directions, or if only the motor 18 is operated
to form turns on the element 7 with the thread taken up from the textile machine at
rest) how many turns have been added from a predetermined number of turns controlled
at the start of operation of the device under examination, in order to maintain this
accumulation constant. In this manner a further closed control loop is achieved for
the number of turns accumulated on the element 7, in order to maintain them constant
at a programmable value. It should be noted that on initial starting of the device
with the textile machine at rest, both the motors 9 and 18 are activated to rotate
in the same direction so that the thread withdrawn from the spool 13 is wound onto
the element 7. Instead of being fed to the machine, this thread is fed to the element
20 which contributes to distributing it on the surface 11 of the element 7 without
withdrawing it from the textile machine. This unique action continues until the required
number of turns (programmed or controlled) are formed on the element 7, the number
being determined as aforedescribed. The device is hence ready to be used to feed the
thread to the textile machine under constant feed (and possibly take-up) tension.
[0049] Control of the number of turns hence utilizes intrinsic means of the device motors,
without adding optical, mechanical or other sensors to measure the "filling" of the
element or accumulator 7 where the element 20 is provided with an eyelet 21A. Otherwise
sensors are necessary for counting the unwinding thread (optical or equivalent), these
being positioned between the element 20 and the thread guide 23 or the sensor 30,
as stated below, to count the thread quantity unwound by the element 7 and passed
freely by sliding on the surface 21 of the element 20.
[0050] Moreover as stated, the device also enables the thread tension to be controlled.
The simplest method to achieve this is to use the tension sensor 30 connected to the
device control unit 200 which, on the basis of the measured tension, acts via independent
closed control loops both on the motor 9 and on the motor 18 to regulate the rotation
of the electric motors themselves. These control loops can be known control algorithms
of PID (proportional-integral-derivative) type. For example, in the case of the element
20 with eyelet 21A, if the thread tension tends to increase, the motor 9 can be accelerated
while at the same time the motor 18 rotates the element 20 in the opposite direction
to the element 7 (and hence in the thread unwinding direction), to make the movement
of the thread from the element 7 to the thread guide 23 as precise and stable as possible
by unwinding it from this element, so decreasing the tension to maintain it constant.
If instead the tension tends to decrease, the element 7 is decelerated while the element
20, rotating in the same direction, takes up part of the thread, this resulting in
an increase in the thread tension in order to oppose the variation and maintain the
tension constant.
[0051] In the case of the element 20 without eyelet 21A, if the thread tension tends to
increase, the motor 9 can be accelerated, the same occurring simultaneously for the
motor 18 which drives the element 20 rotating in the same rotation direction as the
element 7. If the acceleration increase of the motor 9 is not sufficient to maintain
the tension within the control limits, these limits are maintained by increasing thread
withdrawal from the supply present on the element 7, this withdrawal being achieved
freely by the machine and without impediment by the element 20 on whose surface 21
the thread slides freely.
[0052] On termination of thread withdrawal, the motor 9 then restores the supply on the
element 7.
[0053] If the tension tends to decrease, the motor 9 and the element 7 are decelerated while
the element 20 continues to rotate in the same direction to partly take up the machine
thread in order to maintain the tension at the required value and take up any thread
overfeed given by the deceleration limits of the motor 9.
[0054] Alternatively or by integrating the function of the tension sensor 30, again based
on controlling the motor 18, the tension of the thread 12 can be identified and regulated.
In this respect, if the element 20 is provided with an eyelet 21A, as the force exerted
on the thread by this element is proportional to the thread tension and as this force
is proportional to the torque applied by the motor 18 and hence to the current absorbed
thereby, controlling the current absorption by the motor 18 enables the thread tension
to be controlled. By a simple mathematical calculation it is hence possible to relate
each tension to a current absorbed by the motor 18 and hence to regulate this tension
by regulating this absorption.
[0055] The absorbed current can be controlled by known means, for example by known shunt
resistors for measuring the currents absorbed by the motor 18. The same applies to
the motor 9.
[0056] A specific embodiment of the invention has been described in which three control
loops implemented by the unit 200 are used: the first loop between the sensor 30 and
the motor 9; the second loop between said sensor 30 and the motor 18; and finally
the third loop between the number of turns (or thread quantity) accumulated on the
element 7 by the motor 9 and the number of turns added to or subtracted from said
element 7 (or thread quantity wound or unwound) by the motor 18 (see Figure 5).
[0057] Other embodiments are however possible: for example, as already described, the element
20 can be provided with an edge having a plurality of flexible elements (for example
an annular brush mounted on the element 20) with which the thread 12 cooperates, or
with a sinusoidal pattern (with which the thread is always maintained in contact)
to enable the thread to be released by the element 20 when its tension exceeds a predetermined
value close to that which could lead to thread breakage or a processing defect. The
fall in the thread tension (obtained by supplying more thread to the machine by increasing
the rotation of the element 7 or unwinding more thread from it) again results in thread
stabilization (by friction) on the element 20, enabling the required number of turns
to be again restored on the accumulator 7 (by suitably rotating the element 20, as
described, for the purpose of taking thread and rewinding it on the accumulator element
7). The unwound turns can, as already described, be counted by a further sensor, for
example a photoelectric cell or equivalent, positioned between the element 20 and
the thread guide 23 or the tension sensor 30. The tension sensor 30 can also be incorporated
into the thread guide 23 and the actuator motors 9 and 18 can be identical, of the
same type (for example brushless as described) or can be of different type to achieve
different performance in measuring the thread quantity unwound.
[0058] The described invention hence provides three main aspects which can be developed
individually or in combination, i.e.:
- 1) a particular configuration of the motor 9 and shaft 8, both made hollow for passage
of the shaft 17 of the motor 18; 2) a particular configuration of the element 20 with
a surface 21 on which the thread can slide freely, directed to the textile machine
and originating from the element or accumulator 7; and 3) a particular control configuration
by using the sensor 30 with a double feedback control loop both on the motor 9 and
on the motor/actuator 18. Other embodiments are however possible (such as that in
which the motor 18 is replaced by a different actuator, for example a linear or pneumatic
motor) within the scope of the accompanying claims.
1. A device for feeding thread (12) to a textile machine and comprising a casing (1)
containing an electric motor (9) acting on a drive shaft (8) rotating an element or
accumulator (7) about a longitudinal axis (W) of said casing (1), onto said element
or accumulator (7) there being wound the thread (12) withdrawn from a spool or bobbin
(13), there being provided a further rotary element (20) positioned to the front of
the element or accumulator (7), downstream thereof along the path of the thread (12)
towards the textile machine, to cooperate with the thread (12) before this leaves
the feeding device towards the textile machine, said rotary element (20) being associated
with its own rotation actuator (18) which is independent of the aforesaid electric
motor (9) and acts on the thread during its movement towards said textile machine,
said casing (1) comprising hollow portions (2, 3) coupled together and containing
in their interior the electric motor (9) and said rotation actuator (18), said motor
(9) and said rotation actuator (18) being mutually in line, characterised in that said electric motor (9) and the shaft (8) on which it acts are hollow and are traversed
by a drive shaft (17) driven by the rotation actuator (18), the rotary element (20)
being located on said drive shaft (17).
2. A device as claimed in claim 1, characterised in that the actuator (18) for rotating the rotary element (20) is an electrical actuator
such as an electric motor or the like.
3. A device as claimed in claim 1, characterised in that the rotary element (20) is in the form of a solid of rotation of spherical or frusto-conical
cap shape and comprises an outer free surface (21) on which the thread (12) slides
by separating from the element or accumulator (7) and being directed towards the textile
machine, said surface tapering and curving in the direction of movement of the thread
(12).
4. A device as claimed in claim 3, characterised in that said rotary element (20) is without a guide member (21A) for the thread, this latter
moving freely on said outer free surface (21) of said element (20).
5. A device as claimed in claim 4, characterised in that the rotary element (20) has at least one peripheral edge comprising flexible elements.
6. A device as claimed in claim 4, characterised in that the rotary element (20) has at least one irregular edge or sinusoidal profile.
7. A device as claimed in claim 1, characterised in that the rotary element presents a thread guide eyelet (21A) through which the thread
directed to the textile machine passes.
8. A device as claimed in claim 1, characterised in that the rotary element (20) rotates in the same direction as the element or accumulator
(7) about the longitudinal axis (W), but can also rotate in the opposite direction,
said rotary element (20) enabling thread (12) to be taken up from the textile machine
and deposited on the element or accumulator (7) if the machine is of the intermittent
operation type.
9. A device as claimed in claim 4, characterised by comprising sensor means for measuring the quantity of thread unwound from the element
or accumulator (7).
10. A device as claimed in claim 1, characterised in that a tension sensor (30) is present downstream of the rotary element (20) along the
path of the thread (12) directed towards the textile machine.
11. A device as claimed in claim 10, characterised by comprising a thread guide member (23) downstream of the rotary element (20), the
tension sensor (30) defining this thread guide.
12. A device as claimed in claim 1, characterised by comprising a control unit (200) for the electric motor (9) and the rotation actuator
(18), which respectively act on the element or accumulator (7) and on the rotary element
(20).
13. A device as claimed in claims 10 and 12, characterised in that the control unit (200) is also connected to the tension sensor (30), said unit operating
on said motor (9) and said actuator (18) on the basis of the measured tension of the
thread (12), in order to if necessary regulate said tension and maintain it constant
at a freely programmable predetermined value.
14. A device as claimed in claim 12, characterised in that said control unit (200) is connected to measurement means to measure the current
absorption at least of the rotation actuator (18), said unit, on the basis of the
data obtained from said measurement means, identifying each tension variation of the
thread (12) in order to control it at a constant predetermined programmable value.
15. A device as claimed in claim 12, characterised by comprising a means for determining the r.p.m. of the electric motor (9) and of the
rotation actuator (18), said means being connected to the control unit (200) for said
motor (9) and for said actuator (18), said unit (200) determining, from the data obtained
from said means, the quantity of thread (12) accumulated on the accumulator (7), i.e.
a number of turns present on it, this number being programmable and being maintained
constant by controlling said motor (9) and actuator (18) by said unit (200).
16. A device as claimed in claim 1, characterised by comprising an adjustable turn separator member (7K) associated with the element or
accumulator (7), the spacing of said turns on said element (7) being adjusted by adjusting
the inclination of said member (7K) to said element (7).
17. A device as claimed in claims 9 and 12, characterised in that the control unit (200) is connected to the sensor means for the quantity of thread
unwinding from the element or accumulator (7), the unit operating on the electric
motor (9) and on the actuator (18) on the basis of the measured thread quantity wound
onto or unwound from the element or accumulator (7) such as to maintain a constant
supply of thread (12) on this latter.
18. A method for feeding a thread or yarn (12) to a textile machine, said method comprising:
a) unwinding the thread from a bobbin (13),
b) accumulating this thread (12) on an element or accumulator (7) of a device (1)
for feeding the thread to said machine, said element or accumulator (7) being rotated
about its longitudinal axis (W) by an electric motor (9);
c) unwinding the thread from said accumulation element (7) then acting upon said thread
(12) by a further rotary element (20) driven by an independent actuator (18), which
is independent of said electric motor (9) and maintains a constant tension in the
thread (12), said action by said further rotary element (20) taking place by simple
sliding of the thread (12) on a free surface (21) of said element, said surface being
defined by a solid of rotation tapering or curving in the direction of movement of
the thread (12) towards the textile machine, characterised by directly controlling and measuring the tension of the thread (12) downstream of the
rotary element (20), this tension control and measurement implementing the control
and regulation of the movement of said electric motor (9) and of said actuator (18)
to maintain said thread at a preset required tension, that the further rotary element
(20) moving in the same direction as or opposite direction to the element or accumulator
(7) to maintain the thread tension at a constant value.
19. A method as claimed in claim 18, characterised by controlling the quantity of thread unwound from the element or accumulator (7) and
freely passing along the surface (21) of the element (20), this control of the unwound
thread quantity implementing the control and regulation of the electric motor (9)
and of the actuator (18) to maintain a supply yarn quantity on the element or accumulator
(7) at a preset required value.
20. A method as claimed in claim 18, characterised in that said further rotary element (20) moves in the same direction as said element or accumulator
(7) during the starting stage of the textile machine in order to form an adequate
accumulation or stock of thread (12) on said element.
21. A method as claimed in claim 18, characterised in that the further rotary element (20) moves in the same direction as the element or accumulator
(7) in order to take up the thread (12) fed to the textile machine when this latter
is of the intermittently operating type and halts withdrawal of said thread from said
accumulator, said take-up taking place while maintaining the thread tension constant.
22. A method as claimed in claim 18, characterised in that the operation of said electric motor (9) and actuator (18) is controlled by a control
unit (200) to enable an adequate stock to be created on the element or accumulator
(7) or to maintain a constant tension of the thread fed to said machine.
23. A method as claimed in claim 18, characterised by halting the electric motor (9) and rotating only the actuator (18) associated with
the further rotary element (20) for thread take-up.
24. A method as claimed in claim 18, characterised in that the number of turns on the element or accumulator (7) is maintained constant during
normal withdrawal of this thread by the textile machine.
25. A method as claimed in claim 18, characterised by controlling the tension of the thread (12) by controlling the current absorbed by
the actuator (18) associated with the further rotary element (20).
26. A method as claimed in claim 18, characterised in that the number of turns present on the element or accumulator (7) is controlled by controlling
the rotation of the electric motor (9) and of the actuator (18) associated with the
further rotary element (20).
1. Vorrichtung zum Zuführen eines Fadens (12) zu einer Textilmaschine, umfassend ein
Gehäuse (1), das einen elektrischen Motor (9) enthält, der auf eine Antriebswelle
(8) wirkt, die ein Element oder einen Sammler (7) um eine Längsachse (W) des genannten
Gehäuses (1) rotiert, wobei auf das genannte Element oder Sammler (7) der Faden (12)
aufgewickelt ist, der von einer Garnrolle oder Spule (13) abgezogen wurde, wobei ein
weiteres Rotationselement (20) vorgesehen ist, das an dem vorderen Ende des Elementes
oder Sammlers (7) ablaufseitig davon entlang des Weges des Fadens (12) in Richtung
auf die Textilmaschine angeordnet ist, um mit dem Faden (12) zusammenzuwirken, bevor
dieser die Zuführvorrichtung in Richtung auf die Textilmaschine verlässt, wobei das
genannte Rotationselement (20) mit seinem eigenen Rotationsantrieb (18) verbunden
ist, der unabhängig von dem zuvor genannten elektrischen Motor (9) ist und auf den
Faden während dessen Bewegung zu der genannten Textilmaschine wirkt, wobei das genannte
Gehäuse (1) hohle Abschnitte (2, 3) aufweist, die miteinander verbunden sind und in
ihrem Inneren den elektrischen Motor (9) enthalten und den genannten Rotationsantrieb
(18), wobei der genannte Motor (9) und der genannte Rotationsantrieb (18) miteinander
fluchtend ausgerichtet sind,
dadurch gekennzeichnet,
dass der genannten elektrische Motor (9) und die Welle (8), auf die er wirkt, hohl sind
und durch eine Antriebswelle (17) durchlaufen werden, die durch den Rotationsantrieb
(18) angetrieben wird, wobei das Rotationselement (20) auf der genannten Antriebswelle
(17) angeordnet ist.
2. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass der Antrieb (18) zum Drehen des Rotationselementes (20) ein elektrischer Antrieb
ist wie ein Elektromotor oder ähnliches.
3. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass das Rotationselement (20) die Form hat eines Rotationskörpers von kugelkappen oder
kegelstumpfartiger Gestalt und eine äußere Freifläche (21) aufweist, auf der der Faden
(12) beim Loslösen von dem Element oder Sammler (7) gleitet, wenn er zu der Textilmaschine
geführt wird, wobei die genannte Fläche in die Richtung der Bewegung des Fadens (12)
geneigt und gewölbt ist.
4. Eine Vorrichtung gemäß Anspruch 3,
dadurch gekennzeichnet,
dass das Rotationselement (20) ohne ein Führungselement (21A) für den Faden ist, wobei
sich letzterer frei auf der genannten äußeren Freifläche (21) des genannten Elementes
(20) bewegt.
5. Eine Vorrichtung gemäß Anspruch 4,
dadurch gekennzeichnet,
dass das Rotationselement (20) wenigstens eine Umfangskante hat, die flexible Elemente
aufweist.
6. Eine Vorrichtung gemäß Anspruch 4,
dadurch gekennzeichnet,
dass das Rotationselement (20) wenigstens eine ungleichmäßige Kante oder ein sinusförmiges
Profil hat.
7. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass das Rotationselement eine Fadenführungsöse (21A) aufweist, durch die der zu der Textilmaschine
geführte Faden hindurch läuft.
8. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass das Rotationselement (20) in der gleichen Richtung, wie das Element oder der Sammler
(7) um die Längsachse (W) rotiert, aber auch in die entgegengesetzte Richtung rotieren
kann, so dass das Rotationselement (20) dem Faden (12) ermöglicht, von der Textilmaschine
aufgenommen zu werden und auf dem Element oder Sammler (7) abgelegt zu werden, falls
die Maschine von der Art ist mit intermittierendem Betrieb.
9. Eine Vorrichtung gemäß Anspruch 4,
dadurch gekennzeichnet,
dass sie Sensormittel enthält zum Messen der Menge an Faden, die von dem Element oder
Sammler (7) abgewickelt wurde.
10. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass ein Spannungssensor (30) stromab des Rotationselementes (20) entlang des Weges des
Fadens (12), der zu der Textilmaschine geführt ist, vorhanden ist.
11. Eine Vorrichtung gemäß Anspruch 10,
dadurch gekennzeichnet,
dass sie ein Fadenführungselement (23) stromabwärts des Rotationselementes (20) aufweist,
wobei der Spannungssensor (30) diese Fadenführung definiert.
12. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass sie eine Steuereinheit (200) für den elektrischen Motor (9) und den Rotationsantrieb
(18) aufweist, die auf das Element oder Sammler (7) bzw. das Rotationselement (20)
wirken.
13. Eine Vorrichtung gemäß Anspruch 10 und 12,
dadurch gekennzeichnet,
dass die Steuereinheit (200) auch verbunden ist mit dem Spannungssensor (30), wobei die
genannte Einheit auf den genannten Motor (9) und den genannten Antrieb (18) auf der
Basis der gemessenen Spannung des Fadens (12) wirkt, um die genannte Spannung falls
notwendig zu regeln und sie auf einen freiprogrammierbaren vorbestimmten Wert konstant
zu halten.
14. Eine Vorrichtung gemäß Anspruch 12,
dadurch gekennzeichnet,
dass die genannte Steuereinheit (200) mit Messelementen verbunden ist, um den Stromaufnahme
wenigstens des Rotationsantriebes (18) zu messen, wobei die genannte Einheit auf der
Basis der von den genannten Messelementen erhaltenen Daten jede Spannungsveränderung
des Fadens (12) erkennt, um sie auf einen konstanten vorbestimmten programmierbaren
Wert einzuregeln.
15. Eine Vorrichtung gemäß Anspruch 12,
dadurch gekennzeichnet,
dass sie ein Mittel zur Bestimmung der Drehzahl pro Minute des elektrischen Motors (9)
und des Rotationsantriebs (18) enthält, wobei das genannte Mittel mit der Steuereinheit
(200) für den genannten Motor (9) und für den genannten Antrieb (18) verbunden ist,
wobei die genannte Einheit (200) aus den Daten, die sie von dem genannten Mittel erhält,
die Menge an Faden (12) ermittelt, die auf dem Sammler (7) gesammelt ist, d. h. eine
Zahl von Wicklungen, die auf ihm vorliegen, wobei diese Zahl programmierbar ist und
konstant gehalten wird, indem der genannte Motor (9) und Antrieb (18) durch die genannte
Einheit (200) gesteuert werden.
16. Eine Vorrichtung gemäß Anspruch 1,
dadurch gekennzeichnet,
dass sie ein justierbares Wicklungsseparierelement (7K) enthält, das mit dem Element oder
Sammler (7) verbunden ist, wobei der Abstand der genannten Wicklungen auf dem genannten
Element (7) justiert wird durch Einstellung der Neigung des genannten Elementes (7K)
zu dem genannten Element (7).
17. Eine Vorrichtung gemäß Anspruch 9 und 12,
dadurch gekennzeichnet,
dass die Steuereinheit (200) verbunden ist mit den Sensormitteln für die Menge an von
dem Element oder Sammler (7) abgewickelten Faden, wobei die Einheit auf den elektrischen
Motor (9) und den Antrieb (8) auf der Basis der gemessenen Fadenmenge wirkt, die auf
das Element oder den Sammler (7) auf- oder abgewickelt ist, um so einen konstanten
Bestand an Faden (12) auf letzterem beizubehalten.
18. Ein Verfahren zur Zuführung eines Fadens oder Garns (12) zu einer Textilmaschine,
wobei das Verfahren umfasst:
a) Abwickeln des Fadens von einer Spule (13),
b) Sammeln dieses Fadens (12) auf einem Element oder Sammler (7) einer Vorrichtung
(1) zur Zuführung des Fadens zu der genannten Maschine, wobei das genannte Element
oder Sammler (7) um ihre Längsachse (W) durch einen elektrischen Motor (9) gedreht
wird;
c) Abwickeln des Fadens von dem genannten Sammelelement (7), das dann auf den genannten
Faden (12) durch ein weiteres Rotationselement (20) wirkt, das durch einen unabhängigen
Antrieb (18) angetrieben ist, der unabhängig ist von dem genannten Motor (9) und eine
konstante Spannung in dem Faden (12) hält, wobei das genannte Wirken durch das genannte
weitere Rotationselement (20) stattfindet durch einfaches Gleiten des Fadens (12)
auf einer freien Fläche (21) des genannte Elementes, wobei die genannte Fläche definiert
wird durch einen Rotationskörper, der in der Richtung der Bewegung des Fadens (12)
zu der Textilmaschine geneigt oder gebogen ist,
dadurch gekennzeichnet,
dass die Spannung des Fadens (12) stromab des Rotationselementes (20) direkt gesteuert
und gemessen wird, wobei die Spannungssteuerung und -messung die Steuerung und Regulierung
der Bewegung des genannten Motors (9) und des genannten Antriebes (8) durchführen,
um den genannte Faden auf einer vorgegebenen benötigten Spannung zu halten, dass sich
das weitere Rotationselement (20) in der selben Richtung oder in entgegengesetzter
Richtung zu dem Element oder Sammler (7) bewegt, um die Fadenspannung auf einem konstanten
Wert zu halten.
19. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass die Menge an Faden, die von dem Element oder Sammler (7) abgewickelt wird und frei
entlang der Fläche (21) des Elementes (20) läuft, gesteuert wird, wobei diese Steuerung
der abgewickelten Fadenmenge die Steuerung und Regulierung des elektrischen Motors
(9) und des Antriebs (18) durchführt, um eine Bestandsgarnmenge auf dem Element oder
Sammler (7) auf einem voreingestellten benötigten Wert zu halten.
20. Ein Verfahren gemäß Anspruch 19,
dadurch gekennzeichnet,
dass das genannte weitere Rotationselement (20) sich während der Startphase der Textilmaschine
in der gleichen Richtung wie das genannte Element oder der Sammler (7) bewegt, um
eine geeignete Ansammlung oder Vorrat von Faden (12) auf dem genannten Element zu
bilden.
21. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass das weitere Rotationselement (20) sich in der gleichen Richtung wie das Element oder
der Sammler (7) bewegt, um den Faden (12), der zu der Textilmaschine zugeführt wird,
aufzunehmen, wenn letztere von der intermittierend betriebenen Art ist, und das Abziehen
des Fadens von dem genannte Sammler bremst, wobei das genannte Aufnehmen stattfindet,
während die Fadenspannung konstant gehalten wird.
22. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass der Betrieb des genannten elektrischen Motors (9) und des Antriebs (18) durch eine
Steuereinheit (200) gesteuert wird, um die Bildung eines geeigneten Vorrats auf dem
Element oder Sammler (7) zu ermöglichen oder um eine konstante Spannung des Fadens
beizubehalten, der zu der genannten Maschine zugeführt wird.
23. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass der elektrische Motor (9) angehalten wird und nur der Antrieb (18) gedreht wird,
der mit dem weiteren Rotationselement (20) verbunden ist, zur Fadenaufnahme.
24. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass die Zahl der Umdrehungen des Elementes oder Sammlers (7) konstant gehalten wird,
während eines normalen Abziehens des Fadens durch die Textilmaschine.
25. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass die Spannung des Fadens (12) gesteuert wird durch Steuerung des Stroms, der durch
den Antrieb (18), der mit dem weiteren Rotationselement (20) verbunden ist, verbraucht
wird.
26. Ein Verfahren gemäß Anspruch 18,
dadurch gekennzeichnet,
dass die Anzahl der Wicklungen, die auf dem Element oder Sammler (7) vorrätig sind, durch
Steuerung der Drehzahl des elektrischen Motors (9) und des Antriebs (18), der mit
dem weiteren Rotationselement (20) verbunden ist, gesteuert wird.
1. Dispositif pour alimenter une machine textile en fil (12) à une machine textile et
comprenant un boîtier (1) contenant un moteur électrique (9) agissant sur un arbre
d'entraînement (8) faisant tourner un élément ou un accumulateur (7) autour d'un axe
longitudinal (W) dudit boîtier (1), sur ledit élément ou accumulateur (7) on enroule
le fil (12) retiré d'un bobinot ou bobine (13) et on prévoit un autre élément rotatif
(20) positionné sur l'avant de l'élément ou accumulateur (7), en aval de ce dernier
le long de la trajectoire du fil (12) vers la machine textile, afin de coopérer avec
le fil (12) avant que ce dernier quitte le dispositif d'alimentation vers la machine
textile, ledit élément rotatif (20) étant associé avec son propre actionneur de rotation
(18) qui est indépendant du moteur électrique (9) mentionné précédemment, et agit
sur le fil pendant son mouvement vers ladite machine textile, ledit boîtier (1) comprenant
des parties creuses (2, 3) couplées ensemble et contenant dans leur intérieur le moteur
électrique (9) et ledit actionneur de rotation (18), ledit moteur (9) et ledit actionneur
de rotation (18) étant mutuellement alignés, caractérisé en ce que ledit moteur électrique (9) et l'arbre (8) sur lequel il agit sont creux et sont
traversés par un arbre (17) entraîné par l'actionneur de rotation (18), l'élément
rotatif (20) étant positionné sur ledit arbre d'entraînement (17).
2. Dispositif selon la revendication 1, caractérisé en ce que l'actionneur (18) pour faire tourner l'élément rotatif (20) est un actionneur électrique
tel qu'un moteur électrique ou similaire.
3. Dispositif selon la revendication 1, caractérisé en ce que l'élément rotatif (20) se présente sous la forme d'un solide de rotation de forme
sphérique ou tronconique et comprend une surface libre externe (21) sur laquelle le
fil (12) coulisse en se séparant de l'élément ou accumulateur (7) et étant dirigé
vers la machine textile, ladite surface se rétrécissant progressivement et s'incurvant
dans la direction du mouvement du fil (12).
4. Dispositif selon la revendication 3, caractérisé en ce que ledit élément rotatif (20) est sans élément guide (21A) pour le fil, ce dernier se
déplaçant librement sur ladite surface libre externe (21) dudit élément (20).
5. Dispositif selon la revendication 4, caractérisé en ce que l'élément rotatif (20) a au moins un bord périphérique comprenant des éléments flexibles.
6. Dispositif selon la revendication 4, caractérisé en ce que l'élément rotatif (20) a au moins un bord irrégulier ou profil sinusoïdal.
7. Dispositif selon la revendication 1, caractérisé en ce que l'élément rotatif présente un oeillet de guide de fil (21A) à travers lequel passe
le fil dirigé vers la machine textile.
8. Dispositif selon la revendication 1, caractérisé en ce que l'élément rotatif (20) tourne dans la même direction que l'élément ou accumulateur
(7) autour de l'axe longitudinal (W), mais peut également tourner dans la direction
opposée, ledit élément rotatif (20) permettant au fil (12) de remonter de la machine
textile et d'être déposé sur l'élément ou accumulateur (7) si la machine est du type
à fonctionnement intermittent.
9. Dispositif selon la revendication 4, caractérisé en ce qu'il comprend des moyens de capteur pour mesurer la quantité de fil déroulé de l'élément
ou accumulateur (7).
10. Dispositif selon la revendication 1, caractérisé en ce qu'un capteur de tension (20) est présent en aval de l'élément rotatif (20) le long de
la trajectoire du fil (12) dirigé vers la machine textile.
11. Dispositif selon la revendication 10, caractérisé en ce qu'il comprend un élément de guide de fil (23) en aval de l'élément rotatif (20), le
capteur de tension (30) définissant ce guide de fil.
12. Dispositif selon la revendication 1, caractérisé en ce qu'il comprend une unité de commande (200) pour le moteur électrique (9) et l'actionneur
de rotation (18), qui agit respectivement sur l'élément ou accumulateur (7) et sur
l'élément rotatif (20).
13. Dispositif selon les revendications 10 et 12, caractérisé en ce que l'unité de commande (200) est également raccordée au capteur de tension (30), ladite
unité actionnant ledit moteur (9) et ledit actionneur (18) en fonction de la tension
mesurée du fil (12), afin de réguler si nécessaire ladite tension et la maintenir
constante à une valeur prédéterminée librement programmable.
14. Dispositif selon la revendication 12, caractérisé en ce que ladite unité de commande (200) est raccordée aux moyens de mesure pour mesurer l'absorption
de courant au moins de l'actionneur de rotation (18), ladite unité, en fonction des
données obtenues desdits moyens de mesure, identifiant chaque variation de tension
du fil (12) afin de la contrôler à une valeur programmable prédéterminée constante.
15. Dispositif selon la revendication 12, caractérisé en ce qu'il comprend des moyens pour déterminer le nombre de tours par minute du moteur électrique
(9) et de l'actionneur de rotation (18), lesdits moyens étant raccordés à l'unité
de commande (200) pour ledit moteur (9) et pour ledit actionneur (18), ladite unité
(200) déterminant, à partir des données obtenues desdits moyens, la quantité de fil
(12) accumulée sur l'accumulateur (7), c'est-à-dire un nombre de tours présent sur
ce dernier, ce nombre étant programmable et étant maintenu constant en commandant
ledit moteur (9) et l'actionneur (18) avec ladite unité (200).
16. Dispositif selon la revendication 1, caractérisé en ce qu'il comprend un élément de séparateur de tours ajustable (7K) associé avec l'élément
ou l'accumulateur (7), l'espacement desdits tours sur ledit élément (7) étant ajusté
en ajustant l'inclinaison dudit élément (7K) sur ledit élément (7).
17. Dispositif selon les revendications 9 et 12, caractérisé en ce que l'unité de commande (200) est raccordé aux moyens de capteur pour la quantité de
fil déroulé de l'élément ou accumulateur (7), l'unité actionnant le moteur électrique
(9) et l'actionneur (18) en fonction de la quantité de fil mesuré enroulé sur ou déroulé
de l'élément ou accumulateur (7) afin de maintenir une alimentation constante de fil
(12) sur ce dernier.
18. Procédé pour alimenter une machine textile en fil ou filament (12), ledit procédé
comprenant les étapes consistant à :
a) dérouler le fil d'une bobine (13),
b) accumuler ce fil (12) sur un élément ou accumulateur (7) d'un dispositif (1) pour
alimenter ladite machine en fil, ledit élément ou accumulateur (7) étant entraîné
en rotation autour de son axe longitudinal (W) par un moteur électrique (9) ;
c) dérouler le fil dudit élément d'accumulation (7) agissant ensuite sur ledit fil
(12) grâce à un autre élément rotatif (20) entraîné par un actionneur indépendant
(18) qui est indépendant dudit moteur électrique (9) et maintient une tension constante
dans le fil (12), ladite action réalisée par ledit élément rotatif supplémentaire
(20) ayant lieu en faisant simplement coulisser le fil (12) sur une surface libre
(21) dudit élément, ladite surface étant définie par un solide de rotation se rétrécissant
progressivement ou s'incurvant dans la direction du mouvement du fil (12) vers la
machine textile, caractérisé par l'étape consistant à contrôler directement et mesurer la tension du fil (12) en aval
de l'élément rotatif (20), ce contrôle de tension et cette mesure mettant en oeuvre
le contrôle et la régulation du mouvement dudit moteur électrique (9) et dudit actionneur
(18) pour maintenir ledit fil à une tension requise prédéterminée, de sorte que l'autre
élément rotatif (20) se déplace dans la même direction ou dans la direction opposée
à l'élément ou accumulateur (7) pour maintenir la tension du fil à une valeur constante.
19. Procédé selon la revendication 18, caractérisé par l'étape consistant à contrôler la quantité de fil déroulé de l'élément ou accumulateur
(7) et passant librement le long de la surface (21) de l'élément (20), ce contrôle
de la quantité de fil déroulé mettant en oeuvre le contrôle et la régulation du moteur
électrique (9) et de l'actionneur (18) pour maintenir une quantité de fil d'alimentation
sur l'élément ou l'accumulateur (7) à une valeur requise prédéterminée.
20. Procédé selon la revendication 18, caractérisé en ce que ledit élément rotatif supplémentaire (20) se déplace dans la même direction que ledit
élément ou accumulateur (7) pendant l'étape de démarrage de la machine textile afin
de former une alimentation adéquate ou stock de fil (12) sur ledit élément.
21. Procédé selon la revendication 18, caractérisé en ce que l'élément rotatif supplémentaire (20) se déplace dans la même direction que l'élément
ou accumulateur (7) afin de faire remonter le fil (12) fourni à la machine textile
lorsque cette dernière est du type à fonctionnement intermittent et arrête le retrait
dudit fil dudit accumulateur, ladite remontée ayant lieu tout en maintenant la tension
du fil constante.
22. Procédé selon la revendication 18, caractérisé en ce que le fonctionnement dudit moteur électrique (9) et de l'actionneur (18) est commandé
par une unité de commande (200) pour permettre de créer un stock adéquat sur l'élément
ou accumulateur (7) ou pour maintenir une tension constante du fil fourni à ladite
machine.
23. Procédé selon la revendication 18, caractérisé par l'étape consistant à arrêter le moteur électrique (9) et ne faire tourner que l'actionneur
(18) associé à l'autre élément rotatif (20) pour faire remonter le fil.
24. Procédé selon la revendication 18, caractérisé en ce que le nombre de tours sur l'élément ou accumulateur (7) est maintenu constant pendant
le retrait normal de ce fil par la machine textile.
25. Procédé selon la revendication 18, caractérisé par l'étape consistant à contrôler la tension du fil (12) en contrôlant le courant absorbé
par l'actionneur (18) associé à l'élément rotatif supplémentaire (20).
26. Procédé selon la revendication 18, caractérisé en ce que le nombre de tours présent sur l'élément ou accumulateur (7) est contrôlé en contrôlant
la rotation du moteur électrique (9) et de l'actionneur (18) associé à l'élément rotatif
supplémentaire (20).
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