Note: Descriptions are shown in the official language in which they were submitted.
CA 02433215 2003-06-25
-1 -
"REWINDING MACHINE WITH FLANKS CARRYING MATING CENTERS
MOVING ALONG A GLOSED PATH"
DESCRIPTION
Technical field
The invention relates to a rewinding machine for the production of web
reels. More in detail, the invention relates to a rewinding machine of the
type
comprising:
- at feast a first and a second winding cylinder, whose axes are
parallel, defining a winding cradle in which said reels of web are formed, and
- mating centers for engaging and withholding winding mandrels on
which the reels are formed in the winding cradle.,
The invention also relates to a method for the production of reels of
web.
State of the Art
Operations concerning winding or rewinding web are required in the
sector of non-woven processing, e.g. in the production of reels of
semifinished
materials intended for the production of sanitary towels, diapers and the
like,
and also in the production of paper, e.g. for the production of rolls of
toilet
paper, kitchen paper or similar, for the production of reels for' supplying
folding
machines for the production of napkins, paper handkerchiefs and similar
disposable products.
The web production process is continuous and the web is wound on
large diameter parent reels. These reels are later unreeled and the web is
rewound on smaller diameters reels or rolls. For some applications, the web is
cut longitudinally and continuously and wound on winding cores, which can be
made of cardboard, plastic or other suitable material, the core being fitted
and
aligned on a winding mandrel. fn this way, a plurality of reels is produced
with
one single rewinding cycle, each reel being less high than the initial web
width
and, if required, the reels can also be of different heights. The winding
mandrel on which the winding cores are fitted is expandable, e.g.
pneumatically or in any other equivalent way, to secure the winding cores
onto it in the required positions. The various tubular cores - whose
reciprocal
CA 02433215 2003-06-25
..
axial length may be either variable or different - receive corresponding
strips
of web obtained by longitudinally cutting the web from the parent reel.
The rolls or reels are developed in sequence. The finished reel is
unloaded from the winding cradle, e.g. formed by two windirag rollers arranged
side by side, and replaced with a new winding mandrel onto which the winding
cores were previously secured.
A rewinding machine of this type is described inn EP-A-0747308.
Another example of rewinding machine of this type is d~;scribed in EP-A-
1070675. Additional examples of peripheral rewinding machine of the start-
stop type, i.e. in which the supply of web is temporarily interrupted to
replace
the completed reel with another winding mandrel, are described in (aB-A-
2268476, DE-C-3836367, EP-A-0640544.
These rewinding machines must be capable of winding reels or rolls
whose dimensions may be large at considerably high winding speeds.
Typically, the web is fed at speeds exceeding 1000 meters per minute, also in
the order of 2000 meters per: minute. The production rate is consequently
relatively high. The phase in which the finished reel or roll is exchanged
with a
new winding mandrel is the phase of the winding cycle which mostly slows
down the overall production rate. In this phase, in these machines, the
feeding speed of the web is considerable reduced and in certain cases
feeding is stopped for a short time. The machine gradually returns to running
speed after unloading the reel and introducing the new winding mandrel.
Reducing the time required for the exchange operation is consequently
crucial for reducing the winding cycle time.
Objects and summary of the invention
Object of the invention is to provide a rewinding machine of the
aforesaid type in which the rewinding cycle speed can b~e increased and
particularly in which the exchange time, i.e. the time required to replace the
finished reel or roll with a new winding mandrel, is reduced.
This and other objects and advantages, which will be clear those skilled
in the art in the text that follows, are essentially obtained by a rewinding
machine of the above mentioned type, comprising a pair of lateral flanks, on
CA 02433215 2003-06-25
- 3
each of which a corresponding guide defining a closed path is arranged;
along which a plurality of said mating centersa are mobily arranged. The
mating centers are arranged on the two flanks so that each mating center
carried by one of said flanks corresponds to and is axially aligned with a
mating center carried by the other of said flanks. R system is also provided
to
drive the mating centers along each of the guides.
In this arrangement, a first pair of mating centers engages a reel or roll
under formation and a second pair of mating centers engages a new mandrel
simultaneously. The finished reel can be conveyed from the winding cradle to
the unloading area and simultaneously the new mandrel can be conveyed
from a loading area to the winding cradle by moving the pairs of mating
centers along the closed path. This leads to a considerable increase in the
total rewinding cycle speed due to the reduction of the time required to
exchange the reel or roll with a finished mandrel.
In addition to increasing the production cycle speed, the rewinding
machine according to the invention provides a number of additional
advantages. Such advantages include improved control of the reel during the
unloading phase and more accurate control of the web cutting phase for
forming the trailing end of the finished reel and the feeding end of the web
to
be used for winding a new reel t~ be formed on the new mandrel.
Currently, the finished reef or roll is ejected from the winding cradle,
typically defined by a pair of winding cylinders, by pushing and rolling. The
reel is then positioned in an unloading device in a position which is not
exactly
repeatable at each cycle with consequently possible difficulties in the web
cutting phase for starting the winding of the following reel.
In a practical embodiment of the invention, each mating center can be
carried by a respective carriage which slides on thE; guide of the
corresponding flank.
Furthermore, advantageously, it can be foreseen that the path defined
by said guides extends from a first mandrel engagement position to a second
finished reel unloading position; said winding cradle being arranged between
said first and said second position.
CA 02433215 2003-06-25
In a practical and advantageous embodiment, the handling system
comprises a continuous flexible member onto which the mating centers
associated to the respective flanks are secured on each flank. Moreover, a
drive is provided for moving said flexible member. Each m~~tor can drive two
flexible members. In this case, the movements of the mating centers on the
two flanks will be synchronized by means of an appropriate mechanical
transmission. Alternatively, two separate motors can be used and
synchronized electronically by means of a control unit, i.e. using an electric
axis. This solution presents the advantage of avoiding the presence of
cumbersome mechanical members between the two flanks.
Other arrangements of the members moving the mating centers along
the path defined by the guides on the two flanks can be envisaged. For
example, in principle, the mating centers can each be equipped with an
actuator which controls the movement along the guide with a suitable control
for synchronizing the movement of each mating center.
In an advantageous embodiment of the machine according to the
invention, a taker-in is provided to insert the winding mandrels moving from a
collection position of the winding mandrels to a release position of the
winding
mandrels, in correspondence with the positions in which the mandrels are
engaged by the mating centers. The taker-in may consist of a pivoting
member but might also be made in a different way. For example, the winding
mandrels could be inserted axially, i.e. with a movement parallel to their
axis
inside a fixed support, such as a cradle or other. The mandrels can be
collected from this location by the mating centers as they move along said
closed path. Alternatively, the taker-in can be equipped with an insertion
movement which is not pivoting, e.g. by translating from a mandrel collection
position to a mandrel release position.
The winding cylinders can be made so that during the winding phase
the axis of the reel or roll (and consequently of the winding mandrel) is
always
in the same position. This can be obtained in a way which is known per se
employing mobile axis winding cylinders with a vertical movement component
so that the winding cradle is gradually lowered according to the increased
CA 02433215 2003-06-25
-5-
diameter of the reel. In this case, the two flanks can be fixed and the mating
centers can be held constantly at the same height for the entire reel winding
phase. Conversely, if the winding cylinder axis is fixed or if the winding
cylinders move in such a way that the axis of the reel being formed is
provided with a gradual vertical or slanted raising movement, the flanks will
.
also be vertically mobile and actuator means will be provided to control the
upwards and downwards movement of said flanks accordirag to the diameter
of the reel. Synchronization means will be advantageously provided for the
vertical movement of the flanks also in this case.
In general, the two winding cylinders can be mobile one with respect to
the other and can be opened, e.g. one can have a fixed axis and the other a
mobile axis according to a horizontal trajectory. This increases the suporting
base of the reel as it gradually increases in diameter during the winding
operation. In this case, the axis of the reel will follow a more or less
complex
trajectory with a movement which has a vertical component and a horizontal
component. The trajectory followed by the axis of the reel changes according
to the characteristics of the product (specifically its thickness) and the
working
conditions of the machine. The movement can be made by the mating centers
by forming a complexly shaped guide according to the trajectory of the reel
axis or preferably by combining a gradual raising movement of the flanks to a
translating movement of the mating centers along a portion oaf the closed path
which can simply be a straight horizontal portion.
In principle, the rewinding machine can have only two lower winding
cylinders arranged side-by-side, either mobile or fixed as illustrated above,
to
withhold the reel under formation. Preferably, in a way which is known per se,
the rewinding machine comprises a third cylinder whose axis is parallel to the
first and the second winding cylinder arranged over the winding cradle and
mobile to allow for the increased diameter of the reel developing between said
first, second and third cylinder. This arrangement improves reef guidance.
Advantageously, the third cylinder is carried by a pair of pivoting arms whose
fulcrum is in a position which does not interfere with the flanks (which may
be
mobile) carrying the guides which define the closed path full~wed by the
CA 02433215 2003-06-25
_ ' 6
mating centers. The third cylinder can be idle or preferably driven with a
peripheral speed which is essentially equal to the peripheral speed of the
first
and the second winding cylinder, it being understood (in a way that is known
per se) that the three cylinders can have slightly different peripheral speeds
to
obtain the required degree of compactness in winding the reels.
A variable number of mating centers can be provided along each of two
guides carried by said flanks also according to the type of movement adopted.
The number of mating centers on each side will appropriately be equal to at
least three and preferably equal to five.
1nlhen the machine is provided with a taker-in for inserting the winding
mandrels, it can advantageously present a winding mandrel resting cradle
whose geometry corresponds to that of the winding cradle in the initial
winding
phase. As clearly described in the example of embodiment: that follows, this
arrangement ensures correct handling without the need for adjustments in the
presence of mandrels with variable diameters.
According to a possible form of embodiment of the rewinding machine
according to the invention, electric or pneumatic distribution means are
associated to each flank, since the mating centers approach and distance the
mandrel and may be provided with control sensors. Furthermore, the mating
centers can either be idle or driven. A motor is associated to each of said
mating centers in the second case, e.g. an electric motor, iro turn them. The
motor is powered by said electric distribution means.
The distribution means can comprise a rotating di:>tributor for each
flank arranged inside the path defined by the guide along which the mating
centers move and one or more flexible members towards said mating centers.
Preferably, however, an electrical distribution box and a pneumatic
distribution
box can slide along each of said guides; said electrical distribution box and
said pneumatic distribution box can be connected by means of flexible
members to a distributor arranged inside the path defined by the guides along
which the mating centers and said boxes move; and said boxes can be
connected to the mating centers via flexible pneumatic and electric
connections.
CA 02433215 2003-06-25
..
The invention also relates to a method fior the production of reels of
web wound on winding mandrels in which:
- a first winding mandrel is inserted in a winding cradle and a
predetermined amount of web is wound upon it to form a reel; the ends of said
first mandrel being engaged by a pair of mating centers;
- the finished reel is unloaded from the winding cradle and
a second winding mandrel is inserted in said winding cradle.
Characteristically, the method according to the invention comprises the
following phases:
- engaging the first winding mandrel in a collection area by means of
a first pair of mating centers;
- transferring the first winding mandrel by means of said mating
centers to said winding cradle;
- when the reel has been completed, transferring the finished reef
with said first pair of mating centers from said vsrinding cradle to an
unloading
area;
- after transferring said first winding mandrel to the winding cradle
(e.g. while winding said reel), engaging a second winding mandrel with a
second pair of mating centers in said collection area;
- when said reel is removed from the winding cradle, inserting the
second winding mandrel in said winding cradle with said second pair of
mating centers;
transferring the first pair of mating centers towards the collection
area of the winding mandrels.
Additional advantageous characteristics and embodiments of the
machine according to the invention are set forth in the anne~;ed claims.
Brief description of the drawings
The invention will be better understood following the description and
the enclosed drawing, which shows a non-limitative practical embodiment of
the invention. In the drawing, in which identical parts have the same
reference
numerals, it is shown the following:
- Figure 1 is ~ schematic cross-sectional view according to (-I in
CA 02433215 2003-06-25
- $ -
figure 1 of a machine according to the invention;
- Figure 2 is a view according to l l-I l in figure 1;
- Figure 3 is a cross-sectional view according to III-Ill in figure 1;
- Figure 4 is a cross-sections! view IV-IV in figure 1;
- Figure 5 is a front view from inside the machine of one of the flanks
with the pneumatic and electric distribution means;
- Figure 6 is a partial cross-sectional view according to VI-VI in figure
5; and
- Figures 7A-7F show the winding cycle in sequence.
Detailed description of a preferred embodiment of the invention
Above and in the following description, reference is made to the
formation of a reel on the winding mandrel. In actual fact, the reel under
formation can be formed by a plurality of single reels arranged side-by-side
which simultaneously receive the same length of web by winding strips of web
obtained by longitudinally cutting the single incoming web, since the winding
cycle can be carried out on tabular cores axially aligned on the mandrel.
Consequently, in the present description and in the attached claims the term
"reel" can herein indicate a single reel or a plurality of axially aligned
reels
formed at the same time in general.
The rewinding machine comprises a fixed structure 1 with two lateral
flanks fastened to the base. The fixed structure 1 carries a pair of winding
cylinders 3, 5 whose axes are parallel defining ai winding cradle ~' in which
the
winding mandrels are arranged with one or more cores made of cardboard,
plastic or other suitable material fitted upon them. The cores are fitted and
secured on the mandrels by expansion of the mandrels in a way which is
known per se in a station outside the rewinding rnachine.
Cylinders 3, 5 are motor driven (in a way which is known per se) to turn
the winding reel. The web N is turned around winding cylinder 3 which is
supplied along a feeding path defined by rollers 9, 10, 11, 12, 13, 14 from a
parent reel (not shown). Blades (not shown) are arranged along the feeding
path. The blade cuts the web N in the longitudinal direction into strips
corresponding (in terms of dimension and position) to the longitudinal
CA 02433215 2003-06-25
_ 9
dimension and the position of the tubular winding cores inserted on the
winding mandrels which are inserted in the winding cradle 7 as described
below.
The structure 1 also supports a pair of arms 17 pivoting at 19 on the
structure 1. The pair of arms supports a third winding cylinder 21. The latter
can either be idle or driven and rests on the top of the reel under formation,
such that in the winding cradle the reel rests on the lower winding cylinders
3,
5 and is controlled and withheld by the third winding cylinder 21. Reference
numeral 23 indicates the cylinder-piston actuators which control the pivoting
movement of the arms 17 on the fulcrum 19 for gradually raising the upper
mobile winding cylinder 21 white the reel under formation prows in diameter
and for lowering it towards the cradle 7 at the beginning of a new winding
cycle after unloading the finished reel and inserting a new mandrel in the
winding cradle 7.
In the example shown, the winding cylinder 3 has a foxed axis and the
supports are integral with the structure 1 while the axis of the winding
cylinder
5 is mobile in the horizontal direction for the purposes explained below. For
this purpose, the supports are mounted on carriages 25 which slide on
horizontal guides 27 integral with the two flanks of the fixE;d structure 1. A
threaded bar 29 and an actuator 31 control the movement of the carriages 25
along the guides 27 to approach and distance the winding cylinder 5 with
respect to the winding cylinder 3.
A mobile carriage 33 is arranged on the opposite side of the rewinding
machine with respect to the web N feeding path. The carriage 33 moves along
rails 35 integral with the base and equipped with a pair of resting rollers 37
for
distancing the finished reels or rolls from the rewinding machine. Reference
f33 indicates the approaching and distancing mavement of the carriage 33
with respect to the winding area defined by the winding cylinders 3, 5. The
carriage is also equipped with a rolling plane 39 on which the reels to be
distanced are received.
Vertical guides 41 on which the respective flanks 43 slide are integral
with each of the two sides of the structure 1 on the side facing the inside of
CA 02433215 2003-06-25
- -10-
the machine. The two flanks 43 are reciprocally parallel and vertically
ralobile
along the guides 41. Consequently, the two flanks can move on planes which
are parallel to the median plane of the rewinding machine according to the
double arrow f43. The upwards and downwards movement of the flanks 43 is
controlled by a pair of cylinder-piston actuators 45 in which the cylinder is
fastened to the structure 1. A synchronization system comprising a
transversal shaft 47 supported by the flanks of the fixed structure 1 to
synchronize the movements of the two flanks avoiding the possibility of non
identical movements in the vertical direction. Two toothed pulleys 49 are
fitted
near the two ends of the transversal shaft 47 which project outside the flanks
of the structure 1. Respective toothed belts 51 turn on the pulleys, each of
which additionally turns on a respective second toothed pulley 53 carried by
the respective flank. Each toothed belt 51 is fastened in point 55 to the
corresponding flank. In this way, the two flanks 43 are forced to move
identically along the vertical guides 41.
A linear guide 61 defining a closed path is provided on each said flank
43. In the example show, the path consists of two reciprocally parallel
straight
sections whose ends are joined by two semicircular sections of the path.
A plurality of carriages 63 slides along each linear guide 61. Five
carriages for each linear guide 61 and consequently for each flank 43 are
provided in the example shown. The carriages 63 are reciprocally arranged at
an equal distance along the path defined by the guide 61. Each carries a
mating center 65 intended to engage one end of the winding mandrels. The
mating centers 65 can have any possible configuration and, in general, move
axially to approach and distance the winding mandrels and present
expandable heads 67 to be fastened onto the mandrels. Other types of
gripping members can be used instead of expandable heads. APternatively,
single mating centers can be used, which are inserted in the mandrels without
additional tightening effect. This solution is particularly suitak>le if the
mating
centers are not motor driven.
According to the arrangement of the carriages 63 and the respective
mating centers 65 on the two flanks 43, a mating center on one side
CA 02433215 2003-06-25
-11 -
corresponds to a mating center on the opposite side, the mating centers being
axially aligned to engage a respective winding mandrel held parallel to the
axes of the winding cylinders 3, 5, 21.
The carriages 63 associated to each side 43 are fastened to a toothed
belt 68 (or other equivalent flexible member) turning on two toothed pulleys
71, 73. The toothed pulley 71 on each flank 43 is driven by a stepper motor
75 or other suitable actuator for accurately controlling the movement of the
pulley 71 and consequently of the various carriages 63 which are fastened to
the corresponding toothed belt 68 by means of a controlling program. The two
motors 75 associated to the two flanks 43 are joined together by an electrical
axis, i.e. are controlled by a central unit so that the two pulleys 71 and the
two
toothed belts 68 are moved in a perfectly synchronized way. In the example
shown, the motors 75 are on the opposite side of the flanks 43 with respect to
the side on which the guides 61, the carriages 63 with the mating centers 65
and the pulleys 71, 73 with the toothed belt 68 are arranged.
A taker-in 83 is arranged on the inlet side of the web N of the fixed
structure 1 and pivots in point 81 for inserting the winding mandrels with the
respective tubular cores fitted and fastened to triem. The taker-in 83 pivots
on
the axis 81. The pivoting movement is controlled by a cylinder-piston actuator
85 or by a pair of actuators symmetrically arranged on the two flanks of the
machine. The structure 1 carries in addition a V-section fixed duct 87 in
which
the winding mandrels and tubular cores fitted and fastened on them are
axially inserted. The duct 87 presents a comb structure so that the taker-in
83,
also presenting a comb structure, can penetrate inside it.
In its lower position, the taker-in 83 is partially arranged under the
resting surface of the duct 87 so that a mandrel with the respective tubular
cores can be inserted axially along the duct. ~nce the mandoel is positioned
in
the duct 87, the taker-in can pivot upwards thus picking up the mandrel and
bringing it in a position in which it can be engaged by the mating centers 65
which move along the flanks 43 and carried towards the winding cradle.
Alternatively, the duct 87 can be omitted., In this case, the taker-in 83
can be made of continuous profiles inside of being comb-Pike. The mandrel
CA 02433215 2003-06-25
_12_
can thus be axially inserted irk the cradle defined by the taker-in 83 when
this
is in the lower position, shown with a dotted line in figure 1. An appropriate
shape will be adopted for the taker-in to prevent the mandrel from dropping
from the taker-in.
As shown in the drawing, the taker-in 83 presents a profile defined by
two circular cylindrical surface sections corresponding to 'the profile of the
winding cradle formed by the two cylinders 3, 5 when they are in the
maximum approach position. 'this allows the use of mandrels with various
diameters without needing adjustments, as clearly appears in the following
description of machine operation.
The operation of the rewinding machine described above will now be
illustrated with reference to the sequence in figures 7A-7F. In figure 7A, the
five carriages carried by the flank 43 and shown therein are indicated by
reference numerals 63A, 638, 63C, 63D, 63E. Carriage 63A with the
respective mating center is arranged in c~rrespondence with the cradle 7
defined by the winding cylinders 3, 5 which are in the maximum approach
position. The mating center 65 of the carriage 63A and the mating center,
which is axially aligned therewith of the corresponding carriage carried by
the
other flank engage a winding mandrel M with the respective tubular cores
fitted on it. The mating centers of the carriages in position 631E have
unloaded
the previously formed roll, which was already removed. The mating centers
carried by the carriages in position 63B are aligned in corrEapondence with
the top position of the taker-in 83 which contains the winding mandrel M1
which will be inserted in the winding cradle during the following cycle. The
taker-in 83 could actually be still in the lowered position and take the
mandrel
M1 from the duct 87 at a later instant. The reef or roll made during the
previous cycle could also still be inside the machine supportE;d by the mating
centers carried by the carriages 63E or may have been unloaded onto the
carriage 33 and the latter may still be near the pair of winding cylinders 3,
5.
The winding cycle starts in the conditions illustrated ire figure 7A. The
web N is wound on the winding mandrel M on the tubular cores, which are
fitted and fastened on the mandrel. The mating centers which engage the
CA 02433215 2003-06-25
.13_
mandrel M in the winding cradle could be motor driven to turn with the
mandrel but this is not necessary. The torque for turning 'the mandrel and
consequently winding the web is provided by winding cylinders 3 and 5 (which
are motor driven). The upper winding cylinder 21 is lowered and taken into
contact with the winding mandrel in the cradle between the winding cylinders
3 and 5 when a suitable number of turns of web have been formed on the
mandrel.
Progressively, as the web N is wound around the winding mandrel M,
the machine goes from the arrangement shown in figure 7A to the
arrangement shown in figure 7B which differs from the previous arrangement
for the upwards movement of the upper winding cylinder 21 and the
corresponding upwards movement of the flanks 43 due to the upwards
movement of the axis of the reel under formation. This figure shows how the
new winding mandrel M1 being lifted by the taker-in 83 is engaged by the
mating centers carried by the carriages 63B and the taker-in is lowered again
to take a new mandrel.
In figure 7C, the diameter of the reel R has increased again. In order to
provide a large resting base for the reel R, the winding cylinder 5 was
distanced from the winding cylinder 3 with a horizontal movement, causing the
winding cradle 7 to widen in size. This causes the need to translate the
mating
centers of the carriages 63A horizontally in addition to vertically to follow
the
increasing diameter of the reel R. This causes a corresponding movement
along the linear guide 61 of the other two carriages (all reciprocally bound
to
the toothed belt 68) but does not cause problems because the following
winding mandrel M1 has already been engaged by the mating centers in
position 63B while the previous reel has been unloaded by the mating centers
carried by the carriages 63E. A new winding mandrel M2 will have been
introduced in the duct 65 in the meantime for the next winding cycle.
In figure 7D, the winding cylinder 5 appears additionally distanced from
the winding cylinder 3 and the reel R has increased in diameter again
reaching its final dimension. The upper winding cylinder 21 is additionally
raised. The flanks 43 are raised to follow the upwards movement of the axis of
CA 02433215 2003-06-25
-14-
the reel R and consequently of the winding mandrel M while the carriages
carrying the mating centers are translated to follow the movement in the
horizontal direction of the axis of the reel following the opening of the
winding
cylinders 3, 5.
- In figure 7E, the finished reel R has been transferred from the winding
cradle to the carriage 33. For this purpose; the flanks 43 have been slightly
risen to permit the translation of the reel R by moving the carriages 63A
towards the carriage 33. The plane 39 of the carriage 33 is taken to a
position
which is approximately tangent to the winding cylinder 3 and the mating
centers of the carriages 63A are taken over the resting rollers 37 of the
carriage 33. The translation of the carriages 63A causes the translation of
all
the other carriages 63 so that, for example, tile carriage~e 63~ are moved
above the winding cradle 7 enrhich in the meantime has newly decreased in
size because the winding cylinder 5 has approached again the winding
cylinder 3. The upper winding cylinder 21 was raised to allow the passage of
the finished reel.
in figure 7F, the carriage 33 was distanced from the winding cylinders
after that the reel R was deposited by the mating centers carried by the
carriages 63A which were reciprocally distant:ed for this purpose. Cutting
means (not shown, and known per se) are used to transversally cut the web N
between the winding cradle 7 and the finished reel R. The leading edge of the
web which is thus formed is anchored to the tubular cores fitted on the
mandrel M1 which is then introduced in the winding cradles 7. The flanks 43
are lowered to take the mandrel M1 engaged by the mating centers of the
carriages 63B in the winding cradle in contact with the winding cylinders 3,
5.
This downwards movement also takes the mating centers of the carriages
63C into correspondence with the taker-in 83 which in ttte meantime was
raised to take and lift the winding mandrel M2 from the duct 87 to the
position
where it is engaged by the mating centers of the carriages 63C.
Figure 7F - as figure 7A - shows an instant of the winding cycle in
which the mating centers engaging the mandrel which is in the winding cradle
7 and the mating centers engaging the mandrel intendea9 for the following
CA 02433215 2003-06-25
-15-
cycle are in a position which depends on the diametrical dimension of the
winding mandrels, or more precisely on the c9iametrical dimension of the
tubular cores fitted and fastened onto therro. Thanks i:o the particular
configuration of the taker-in 83, which presents a profile that copies that of
the
winding cradle in this configuration, it is sufficient to adjust the position
of the
mating centers with respect to the winding cylinders 3, 5 to automatically
obtain the correct position of the mating centers with respect to the seat
defined by the sections which form the taker-in 83 as the diameter of the
tubular cores varies.
From the description above, it is clear 1'~~hat the unloading phase of
finished reel R and the introduction of a new winding mandrel in the cradle 7
is much faster than what occurs in rewinding machines of the traditional type.
This reduces the overall duration of a winding cycle. Furthernnore, the
finished
reel R is controlled and guided until it reaches the rollers 37 of the
carriage 33
and this facilitates the unloading operations of the reel and the cutting of
the
web because the position which the reel R assumes on tree carriage 33 is
always accurately repeatable.
It is clear form what has been described above, that the mating centers
65 and the respective heads 67 are mobile. Particularly, the mating centers
are provided with approaching and distancing movement with respect to the
winding mandrels for gripping and releasing and with a fastE;ning movement,
e.g. expansion of the heads 67, to fasten the winding mandirel which is used
at the time by a pair of mating centers. As mentioned, the mating centers may
be motor driven. This means that electrical signals must beg provided to the
mating centers for the control units which operate the mechanical members
~e.g. solenoid valves or other). The possibility of sending or receiving
electrical signals to and from the mating centers obtained sria sensors, e.g.
enabling signals for carrying out the various functions of the cycle in
sequence. FinaIPy, the mechanical members must be operatE;d via pneumatic
or hydraulic controls, reasons for which compressed air or other pressurized
fluid must be supplied to the mating centers.
For this purpose, in the illustrated embodiment, a rotay compressed air
CA 02433215 2003-06-25
' 16'
and electrical signal distributor is required to operate the mechanical
members arranged inside the closed path defined by the linear guide 61 of
each flank 43 in a position which is slightly central with respect to said
path:
The rotating distributor and the connection means to 'the electric and
pneumatic line to the various mating centers are indicated only in figures 3,
5
and 6, while they are substantially omitted in the remaining figures of the
drawing for the sake of clarity.
The rotating distributor is generally indicated with reference numeral
91. The rotating distributor is connected by means of at lea>>t an electric
wire
to an electric unit 93 fitted on a carriage 94 sliding on the same guide 61 on
which the carriages 6~, carrying the mating centers 65; slide. The carriage 94
can also be fastened to the corresponding toothed belt 68. Reference
numeral 95 indicates a flexible channel in which the electric wire is
arranged,
one end of the channel being connected to the rotating distr~,ibutor 91 and
the
opposite end to the electric unit carriage 94: The electric wire is not shown
in
the drawing for the sake of simplicity.
The electric unit 93 is connected in series to the carriages 63 and from
here to the various mating centers carried by the carriages by means of
electric wires arranged in flexible channels 97. each channel 97 joins a
carriage 63 to an adjacent carriage. In this way, the electricall signals
supplied
via the rotating distributor 91 reach all the mating centers on the respective
flank 43.
A compressed flexible air conduit also passes in the channel 95. The
compressed air line is also passed to a pneumatic unit 1 (>1 and to all the
carriages 63 and finally to the respective mating centers 65 via channels 99
which are parallel to channels 9?. In this way, the compressed air reaches all
the mating centers and the respective actuators which are controlled by the
compressed air with control signals distributed along the electrical line
which
from the rotating distributor 91 reaches the electric unit 93 and from here
all
the carriages 63.
in the example described above, the winding cylinders 3, 5 are
reciprocally mobile to increase the resting base during the winding cycle as
CA 02433215 2003-06-25
-17-
the diameter of the reel R under formation increases. This characteristic is
advantageous specifically for reels R whose final diameter is particularly
high.
The machine can be programmed so that the winding rollers only open arid
close if the diameter of the reel exceeds a certain value. The opening
movement can be controlled, for example, according to the amount of wound
web determined by means of an encoder associated to one of the cylinders or
rollers arranged along the material path or also to one of the two winding
cylinders. Alternatively, the diameter can be controlled and the cylinders can
be opened according to the respective signal.
Since the opening of the winding cylinders is required to make the
winding operation more stabile either eliminating or limiting reel vibrations,
according to a possible form of embodiment, opening movement control of the
two cylinders can be consequent to a signal front load cells associated to the
mating center supports 65. When these load cells or other equivalent sensors
detect a vibration exceeding a predetermined threshold value, the rewinding
machine control unit controls the gradual opening of the cylinders 3, 5 until
the
detected vibration is again reduced to an acceptable value.
It is noted that the drawing shows just one embodiment of the
invention, which may vary in shapes and arrangements, without departing
from the scope of the present invention. The presence of reference numerals
in the annexed claims has the purpose of facilitating comprehension of the
claims with reference to the preceding description and the annexed drawings
and does not limit its scope of protection.
