The present invention relates to methods and apparatus
for unwinding web materials. More particularly, the invention pertains to methods
and apparatus for unwinding web materials having a plurality of narrow lanes.
The manufacture of products such as disposable absorbent
articles involves the use of narrow webs of flexible material. Such flexible materials
can include, by way of illustration, nonwoven materials, elastic materials, adhesive
tapes, polymeric films, release paper, mechanical fastening materials or the like.
Due to their narrow widths, these flexible materials and others of this type present
special handling difficulties.
For example, narrow web materials are sometimes processed
in the form of planetary wound rolls, often called "cookie rolls" or "cookies" where
the narrow web material is wound directly upon itself to form a narrow roll. Given
the width of the web material, however, these very narrow rolls can be unstable
and tend to warp or fall apart when lifted. Support members can be used to protect
the cookie from distortion or damage, but that introduces a new structure and increases
the processing cost of the web material and the cost to change rolls. Moreover,
individual cookie rolls have a relatively short run time, which undesirably leads
to frequent roll changes.
To circumvent these difficulties, narrow web materials
can be level wound. By oscillating the narrow web material back and forth across
the roll during winding, the level winding process yields a stable roll form that
resists damage. Again, however, the level winding process can add significant expense
to the web material.
Certain web materials such as molded hook fasteners have
been formed into wide intermediary tapes. These wide tapes include strips of hook
material separated by splitting channels or perforations. Processing of such wide
tapes has to date required simultaneously separating the strips of hook material
using specialized equipment such as splitting combs or slitting blades. Not only
is such specialized equipment expensive to obtain and operate, but its use is practical
only for converting operations that can accommodate simultaneous processing of multiple
In view of these deficiencies and limitations with conventional
manufacturing operations, it would be desirable to have improved methods and apparatus
for unwinding narrow web materials.
In response to the above-referenced deficiencies and limitations,
a new method of unwinding a web material has been discovered. The method includes
providing a roll of web material that defines a plurality of integral lanes with
a separator disposed between the lanes, and tearing the web material along the separator
to disconnect at least one lane from at least one other lane. The selected lane
is unwound from the roll while continuing to tear the web material along the separator
and maintaining the other lane on the roll.
With this method, the parent roll can contain a relatively
wide web of material that consists of a plurality of lanes of web material. The
parent roll can provide a high degree of roll stability to minimize damage to the
material during handling and storage operations. The individual lanes of web material
can be unwound sequentially from the parent roll. In this way, only the number of
lanes that are required for immediate processing need to be unwound. The remainder
of the lanes can remain wound on the parent roll. This method can provide a stable
roll form for delivering narrow lanes of material, without requiring an additional
slitting operation and without the added expense of level winding or support members.
It is especially significant that the web material includes
separators that enable the web material to be torn into individual lanes or groups
of lanes. The terms "torn" and "tearing" in the context of this application mean
that at least one lane of the web material can be or is separated from at least
one other lane of the web material without using a cutting or slitting device. Separators
can comprise any structure or treatment that causes the web material to tear into
distinct lanes. In particular embodiments, suitable separators can comprise perforated
regions, intermittently cut or slit regions, score marks, reduced thickness or reduced
integrity regions, including splitting channels, creased regions, added elements
or treatments that direct or limit tearing to a defined area, molded or embossed
indentations, or the like. Perforation or scoring devices can be incorporated into
the web production process or as a later converting step for the web material. The
perforation or scoring devices can continuously or intermittently perforate, cut,
or indent the web material. Alternatively, for molded web materials the material
can include integral, molded-in splitting channels. The splitting channels can comprise
generally longitudinal regions that have a relatively lower basis weight or less
durable structure, so that the lanes can be separated along the splitting channels.
Forming the web material so that it can be torn without the use of a cutting or
slitting device simplifies the unwinding operation and reduces equipment and maintenance
The manner in which the remaining lanes of web material
are maintained on the parent roll will depend to some extend of the nature of the
web material. In most cases, it may be sufficient to hold the leading ends of the
remaining lanes of web material against the roll. Various means can be used to hold
the remaining lanes in place, including but not limited to items such as tape, clips,
clamps, bands, adhesives, cords, covers, or the like.
The present method is particularly suited for narrow webs
of flexible material. The individual lanes can have any desired width, such as about
5 cm. or less or about 2 cm. or less. The parent roll on the other hand can be relatively
wide and can contain any number of lanes depending upon the width of the lanes.
For lane widths on the order of 2 cm., for example, the web material on the parent
roll can comprise 2 or more lanes, particularly 4 or more lanes, more particularly
8 or more lanes, such as 10 to 60 lanes or more.
The present method can be used for unwinding a variety
of flexible materials, such as nonwoven materials, elastic materials, adhesive tapes,
polymeric films, release paper, mechanical fastening materials, or the like. Mechanical
fastening materials can comprise interlocking geometric shaped materials, such as
hooks, loops, bulbs, mushrooms, arrowheads, balls on stems, male and female mating
components, buckles, snaps, or the like. In particular embodiments, the mechanical
fastening materials comprise hook-and-loop fastening elements. Loop type fasteners
typically comprise a fabric or material having a base or backing structure and a
plurality of loop members extending upwardly from at least one surface of the backing
structure. The loop material can be formed of any suitable material, such as acrylic,
nylon or polyester, and can be formed by methods such as warp knitting, stitch bonding
or needle punching. Suitable loop materials are available from Guilford Mills, Inc.,
Greensboro, North Carolina, U.S.A. under the trade designation No. 36549. Another
suitable loop material can comprise a pattern un-bounded web as disclosed in
U.S. Patent 5,858,515 issued January 12, 1999
to Stokes et al.
Hook type fasteners typically comprise a fabric or material
having a base or backing structure and a plurality of hook members extending upwardly
from at least one surface of the backing structure. In contrast to the loop type
fasteners which desirably comprise a very flexible fabric, the hook material advantageously
comprises a more resilient material to minimize unintentional disengagement of the
fastener components as a result of the hook material becoming deformed and catching
on clothing or other items. The term "resilient" as used herein refers to an interlocking
material having a predetermined shape and the property of the interlocking material
to resume the predetermined shape after being engaged and disengaged from a mating,
complementary interlocking material. Suitable hook material can be molded or extruded
of nylon, polypropylene or another suitable material. Hook materials are available
from commercial vendors such as Velcro Industries B.V., Amsterdam, Netherlands or
affiliates thereof, including specific materials identified as Velcro HTH-829 with
a uni-directional hook pattern and having a thickness of about 0.9 millimeters (35
mils) and HTH-851 with a uni-directional hook pattern and having a thickness of
about 0.5 millimeters (20 mils); and Minnesota Mining & Manufacturing Co., St. Paul,
Minnesota U.S.A., including specific materials identified as CS-600.
Hence, in another embodiment, the invention concerns a
method of unwinding a mechanical fastener material. The method includes providing
a roll of mechanical fastener material comprising a base and a plurality of engaging
elements projecting from the base. The mechanical fastener material defines at least
3 lanes containing engaging elements with integral separators disposed between the
lanes. The lanes can have a width of about 5 cm. or less. The method also includes
tearing the mechanical fastener material along a separator to disconnect at least
one lane from a plurality of other lanes, and unwinding the one lane from the roll
while continuing to tear the mechanical fastener material along the separator. The
plurality of other lanes are maintained on the roll while the one lane is unwound.
In particular embodiments the web material can comprise
a hook material. The multiple lane configuration can be produced in-line in the
hook production process. The parent rolls can be produced in relatively wide widths,
for example from about 7 to about 100 cm. depending on the manufacturer's width
constraints and tension tolerances. In one particular embodiment, by way of illustration,
the web material can be divided into lanes having a width of about 1.3 cm. with
separators disposed between the lanes. The separators can comprise longitudinal
channels or splitting lanes of reduced thickness. For example, the base of the hook
material can have a nominal thickness of about 0.3 millimeters (mm.) and the separators
can have a nominal thickness at their center of about 0.05 mm. The separators can
be very narrow, such as on the order of about 0.2 mm. Alternatively, the web material
can comprise loop material or other mechanical fastening material.
In another aspect, the present invention also concerns
an apparatus for unwinding a roll of web material having first and second integral
lanes. The apparatus includes at least one roll unwind stand comprising a shaft
defining an unwind axis and a drive mechanism adapted to rotate the shaft. A repositioning
device, which is adapted to redirect a lane as it is unwound, is movably mounted
and positionable at a plurality of positions along an axis generally parallel to
the unwind axis. The plurality of positions correspond to different lane positions.
The apparatus also includes a control system adapted to: move the repositioning
device to a first location corresponding to at least one first lane, rotate the
drive mechanism to unwind the at least one first lane, move the repositioning device
to a second location corresponding to at least one second lane, and rotate the drive
mechanism to unwind the at least one second lane. The second lane can remain on
the roll while the fist lane is unwound.
The apparatus can also employ sensors that provide roll
diameter information. Thus, in another embodiment, an apparatus for unwinding rolls
of web material having a plurality of integral lanes can comprise first and second
roll unwind stands. The unwind stands comprise shafts defining unwind axes and one
or more drive mechanisms adapted to rotate the shafts. A repositioning device is
associated with each roll unwind stand and, is adapted to redirect a lane as it
is unwound. The repositioning devices are movably mounted and positionable at a
plurality of positions along an axis generally parallel to the respective unwind
axis. The plurality of positions correspond to different lane positions. A sensing
device is associated with each roll unwind stand and is adapted to provide roll
diameter information. The sensing devices are movably mounted and positionable at
a plurality of positions along an axis generally parallel to the respective unwind
axis. Again, the plurality of positions correspond to different lane positions.
The apparatus also includes a control system adapted to: move the repositioning
and sensing devices of the first roll unwind stand to a first location corresponding
to at least one first lane, rotate the drive mechanism of the first roll unwind
stand to unwind the at least one first lane, move the repositioning and sensing
devices of the first roll unwind stand to a second location corresponding to at
least one second lane, rotate the drive mechanism of the first roll unwind stand
to unwind the at least one second lane, move the repositioning and sensing devices
of the second roll unwind stand to a first location corresponding to at least one
first lane, rotate the drive mechanism of the second roll unwind stand to unwind
the at least one first lane, move the repositioning and sensing devices of the second
roll unwind stand to a second location corresponding to at least one second lane,
and rotate the drive mechanism of the second roll unwind stand to unwind the at
least one second lane. The second lanes can remain on their corresponding rolls
while the first lanes are unwound.
In particular embodiments, the sensing devices can detect
the position of the next lane to be unwound. Further, the control system can use
sensor feedback information to control the position of the repositioning devices.
The apparatus as described herein can be used to unwind
a roll of web material having first and second integral lanes, including the steps
of: positioning a repositioning device at a first position corresponding to the
position of the first lane, where the repositioning device is adapted to redirect
a lane as it is unwound; initiating separation of the first lane from the integral
second lane; feeding the first lane onto the repositioning device; rotating the
roll to unwind the first lane while tearing the first lane from the second lane
and maintaining the second lane on the roll; moving the repositioning device to
a second position corresponding to the position of the second lane; feeding the
second lane onto the repositioning device; and rotating the roll to unwind the second
The present invention facilitates high-speed manufacturing
of products such as absorbent articles, including diapers, training pants, incontinence
products, diaper pants, feminine care products, swim pants, disposable underwear,
or the like. The multiple lane configuration of the web material is particularly
suited for use with production of such garments, which often employ two or more
pieces formed of narrow web material such as mechanical or adhesive fasteners. In
manufacturing such garments, it can be advantageous to unwind a single lane of web
material and subsequently tear or cut the single lane into two or more individual
strips. The strips can then be cut and applied to the garment so that there are
two fasteners per product.
Particular training pants suitable for use with the present
invention are disclosed in
U.S. Patent Application Serial No. 09/444,083, filed on November 22, 1999
PCT application WO 00/37009 published June 29, 2000) by A. Fletcher et al.
and titled "Absorbent Articles With Refastenable Side Seams;" which is
incorporated herein by reference. This reference describes various materials and
methods for constructing training pants. Other methods and apparatus concerning
the manufacture of training pants are disclosed in
U.S. Patent 4,940,464 issued July 10,1990 to Van Gompel et al.
U.S. Patent 5,766,389 issued June 16, 1998 to Brandon et al.
; which are also incorporated herein by reference.
The above-mentioned and other features and advantages of
the present invention and the manner of attaining them will become more apparent,
and the invention itself will be better understood by reference to the drawings
and the following description of the drawings.
Within the context of this specification, each term or
phrase below will include the following meaning or meanings.
"Bonded" refers to the joining, adhering, connecting, attaching,
or the like, of two elements. Two elements will be considered to be bonded together
when they are bonded directly to one another or indirectly to one another, such
as when each is directly bonded to intermediate elements.
"Comprising" is inclusive or open-ended and does not exclude
additional, unrecited elements or method steps.
"Connected" refers to the joining, adhering, bonding, attaching,
or the like, of two elements. Two elements will be considered to be connected together
when they are connected directly to one another or indirectly to one another, such
as when each is directly connected to intermediate elements.
"Disposable" refers to articles which are designed to be
discarded after a limited use rather than being laundered or otherwise restored
"Disposed," "disposed on," and variations thereof are intended
to mean that one element can be integral with another element, or that one element
can be a separate structure bonded to or placed with or placed near another element.
"Elastic," "elasticized" and "elasticity" mean that property
of a material or composite by virtue of which it tends to recover its original size
and shape after removal of a force causing a deformation.
"Fabrics" is used to refer to all of the woven, knitted
and nonwoven fibrous webs.
"Flexible" refers to materials which are compliant and
which will readily conform to the general shape and contours of the wearer's body.
"Force" includes a physical influence exerted by one body
on another which produces acceleration of bodies that are free to move and deformation
of bodies that are not free to move. Force is expressed in grams per unit area.
"Integral" is used to refer to various portions of a single
unitary element rather than separate structures bonded to or placed with or placed
near one another.
"Layer" when used in the singular can have the dual meaning
of a single element or a plurality of elements.
"Member" when used in the singular can have the dual meaning
of a single element or a plurality of elements.
"Nonwoven" and "nonwoven web" refer to materials and webs
of material which are formed without the aid of a textile weaving or knitting process.
"Surface" includes any layer, film, woven, nonwoven, laminate,
composite, or the like, whether pervious or impervious to air, gas, and/or liquids.
These terms may be defined with additional language in
the remaining portions of the specification.
The above-mentioned and other features of the present invention
and the manner of attaining them will become more apparent, and the invention itself
will be better understood by reference to the following description and the accompanying
drawings, wherein similar features in different figures have been given the same
- Figure 1 schematically illustrates one embodiment of a process and apparatus
for unwinding a web material according to the present invention.
- Figure 2 illustrates a top plan view of a web material of the type shown in
- Figure 3 illustrates a sectional side view of an exemplary hook fastening material
for use with the methods and apparatus of the present invention.
- Figure 4 illustrates a sectional end view of the hook fastening material shown
in Figure 3.
- Figure 5 illustrates a front elevation of a further embodiment of a process
and apparatus for unwinding a web material according to the present invention.
- Figure 6 illustrates a top plan view of the process and apparatus of Figure
- Figure 7 illustrates a right side view of the process and apparatus of Figure
- Figure 8 illustrates a left side view of the process and apparatus of Figure
The principles of the present invention can be used with
a variety of material webs that can be incorporated into an even greater variety
of products. For ease of explanation, the description hereafter will be in terms
of a hook fastener material for use in disposable training pants.
One embodiment of a process and apparatus for unwinding
web materials is schematically illustrated in Figure 1. The web material 20, separately
shown in Figure 2, includes a plurality of narrow lanes 22 with separators 24 disposed
between the lanes. The web material can be torn along a separator in order to disconnect
at least one selected lane 26 from one or more remaining lanes 28. As the selected
lane is unwound from the roll, the web material can be further torn along the separator
so that the remaining lanes remain on the roll. The ends of the remaining lanes
28 can be taped down to the roll to keep them from unwinding prematurely.
To facilitate high speed operations, the process can include
two or more driven rolls 30, 32 of multi-lane web material. As shown in Figure 1,
a selected lane from a first parent roll 30 can be led around a turnbar 34 to a
splicing unit 36. From there the selected web can enter a festoon section 38, past
a driven roll 40 and into a dancer roll 42. Upon exiting the dancer roll, the selected
lane can be divided at a slitter station 44 into first and second individual strips
46, 48. Each strip can be transported to an application station 50 for incorporation
into an intermediate or finished product. In this way, the present process allows
two very narrow strips of material to be supplied to a garment assembly machine
simultaneously from a stable roll configuration with a long run time. The selected
lane can alternatively be incorporated directly into an intermediate or finished
product without slitting into individual strips and/or without the other intervening
In the process illustrated in Figure 1, a selected lane
52 from a second parent roll 32 can be partially unwound and led around the turnbar
34 to the splicing unit 36. As described in greater detail below, the selected lane
52 from the second parent roll can be spliced to the tail of the selected lane 26
from the first parent roll for continuous high speed operation. This sequence can
be repeated by selecting adjacent remaining lanes from the rolls 30, 32 and separating
and unwinding such lanes relative to the other remaining lanes. Conventional equipment
can be used for the various web handling operations, provided it is suitable for
the particular web material being processed. Such web handling equipment is available
from a variety of commercial vendors, such as Martin Automatic, Inc. of Rockford,
As used herein, the term "lane" refers to the width of
material that is unwound from a parent roll which has multiple lanes across its
width; the lanes can but need not comprise narrower "strips" that jointly form a
lane. With reference to Figure 2, which represents a top plan view of an exemplary
web material, a web material can be formed with a plurality of lanes 22 with a separator
24 disposed between each lane. Each lane 22 comprises two strips 56, 57 with another
separator 58 disposed between each strip of each lane. The illustrated web material
could alternatively be unwound in lanes that each comprise a different number of
strips. For particular operations, it might be desirable to consecutively unwind
lanes with a different number of strips from a single roll.
The separators 24 used between lanes 22 can be the same
as or different than the separators 58 used between individual strips 56, 57. For
instance, it may be desirable for the separators 24 used between lanes to tear more
easily than the separators 58 used between individual strips. Different separators
can comprise splitting channels formed with different depth or width dimensions;
score marks or perforations with different dimensions or penetration depths; or
The web material 20 can comprise a hook fastening material
such as the type illustrated in Figures 3 and 4. The side section view of Figure
3 is taken from a plane parallel to the separators 24, and the end section view
of Figure 4 is from a plane perpendicular to the separators 24. The exemplary hook
fastener material 20 can comprise groupings 60 of hooks 62 that are arranged in
a plurality of rows. The hooks desirably extend upward from a base 64 of the hook
material. Rip-stops 66 which are known and commonly employed in the art can be incorporated
in the hook material between the hooks. The hooks can all face in the same direction
as illustrated or can face in multiple directions. The groupings of hooks can but
need not be separated from one another by selvage areas 68. Longitudinal separators
24 in the form of narrow splitting channels can be disposed between the groupings
of hooks, such as in the selvage areas. The hooks, base, rip-stops and separators
can be integrally formed, in a wide variety of sizes, shapes and patterns. Examples
of particular hook materials and their method of manufacture are disclosed in
U.S. patents 4,794,028 issued December 27, 1988 to Fisher
5,997,522 issued December 7, 1999 to Provost et al.
, which are incorporated herein by reference. Suitable hook materials are
available from various commercial vendors such as Velcro Industries B.V., Amsterdam,
Netherlands or Minnesota Mining & Manufacturing Co., St. Paul, Minnesota, U.S.A.
A further embodiment of the present process and apparatus
is illustrated in Figures 5-8. The first and second parent rolls 30, 32 of web material
20 are shown mounted on shafts 70 of a dual roll unwind stand 72. The unwind stand
comprises a base plate 74 and a frame structure 76 mounted on the base plate. Rotary
drive mechanisms 78 are attached to the frame and operatively connected to the shafts
to unwind the parent rolls. The unwind stand can include backing plates 80 connected
to each shaft to support and/or limit axial movement of the drive side of the rolls
With particular reference to Figure 5, a selected lane
26 is illustrated being unwound from the first parent roll 30 in the direction of
arrow 82. The selected lane 26 can be led over upper idler rolls 84 and 85, twisted
90 degrees, and fed onto an upper repositioning device 86. The term "repositioning
device" as used herein refers to a driven roll, idler roll, turn bar, dead bar,
web guide or the like that is adapted to redirect a lane as it is unwound. In the
illustrated embodiment, the upper repositioning device comprises an upper idler
roll 86 which redirects the selected lane 26 so that it is transported in a direction
into the page of Figure 5. With additional reference to Figures 6 and 8, the selected
lane 26 thereafter travels through the splicing unit 36, into a festoon section
38, past a driven roll 40 and to a dancer roll 42.
A selected lane 52 from the second parent roll 32 is illustrated
as having been threaded in the direction of arrow 88 and is to be fed to the splicing
unit 36. This selected lane 52 is pulled off the second parent roll over lower idler
rolls 90, 91 and 92, twisted 90 degrees, and fed onto a lower repositioning device
94. In the illustrated embodiment, the lower repositioning device comprises a lower
idler roll 94 which redirects the selected lane 52 from the second parent roll 32
generally parallel to the selected lane 26 from the first parent roll 30 and into
the splicing unit 36. As further illustrated, idler rolls 84-85 and 90-91 can be
positioned to form S-wrap configurations to provide consistent entry and exit points
to the change in web direction, and could alternatively comprise two free turning
idler rolls, fixed shafts, turn bars, or the like.
Upper and lower trolley members 100 and 102 are used in
the illustrated embodiment to carry the upper and lower idler rolls 86 and 94, respectively.
The trolley members 100 and 102 can be slideably mounted on a beam member 104 (Figures
6 and 8), which can be fixedly mounted at one end to the frame structure 76. Various
mechanisms can be used to permit movement of the trolley members 100 and 102 along
the beam member 104, such as a dovetail slide with a locking mechanism, a ball-slide,
a combination ball-slide arrangement with a ball-screw mechanism for movement, a
slotted mounting bracket, a cantilevered piece of bar stock with a clamping device,
or the like. The upper trolley member 100 (Figures 5,6 and 8) can be movably mounted
on an upper portion of the beam member 104. The upper idler roll 86 can be rotatively
mounted on the upper trolley member 100. Similarly, the lower trolley member 102
can be movably mounted on a lower portion of the beam member 104, and the lower
idler roll 94 can be rotatively mounted on the lower trolley member 102. The upper
trolley member 100 can be adapted to move along the beam member 104 so that it is
properly positioned for unwinding of each lane 22 of the first parent roll 30. Likewise,
the lower trolley member 102 can be adapted to move along the beam member 104 so
that it is properly positioned for unwinding of each lane 22 of the second parent
roll 32. In particular, the trolley members 100 and 102 can be positioned at a plurality
of positions along an axis generally parallel to the axis of the unwind shafts 70,
so that the idler rolls 86 and 94 can be radially aligned with the particular lane
being unwound. The upper and lower trolley members 100 and 102 are desirably capable
of moving independently of one another.
Each trolley member can be adjusted by sliding it along
the beam so that the center of the idle roll 86 or 94 is approximately aligned with
the center of the lane being unwound. The trolley member can be reversibly locked
in position with a hand-tightened set screw or other suitable means. The trolley
members 100 and 102 can be adjusted manually, mechanically or electromechanically
to correspond with the position of a diameter sensor 130, 132. Suitable mechanical
position control devices can comprise a ball-screw linear actuator, pneumatic, hydraulic
or servo cylinder, rack and pinion gear assembly, or the like, which can but need
not necessarily use the sensors to detect the position of the unwinding lane.
The unwind process and apparatus desirably but not necessarily
employ sensors 130, 132 to provide greater opportunity for automated operation.
The sensors can detect the presence and location of the web material 20. The sensors
can be used to detect the presence and location of the unwinding lane and provide
feedback on the diameter of the lane, allowing accurate speed calculations as the
lane diameter diminishes. Feedback from the diameter sensors 130, 132 can be used
in combination with a microcontroller, computer or the like to provide automatic
tracking of the successive unwind lanes, thereby minimizing operator intervention
between parent roll changes. One particular sensor that is suitable for the present
process is a laser sensor available from SICK OPTIK ELECTRONIK, Inc., a business
having offices in St. Paul, Minnesota U.S.A. Narrow beam or contact sensors can
be used and are preferred to broad parabolic beam type sensors. Data from the sensors
is desirably provided to a control system 140 (schematically illustrated in Figure
5) that controls the unwinding process. Suitable control systems are available from
various commercial vendors, such as Allen-Bradley, Milwaukee, Wisconsin U.S.A.
In the illustrated embodiment, first and second sensors
130, 132 are moveably mounted on rails 110 attached to the frame 76. With particular
reference to Figures 5 and 7, the first sensor 130 and the second sensor 132 can
each be mounted on brackets 112 that are slideable along the rails 110. The brackets
can move independently from one another and independently from the idler rolls 86
and 94. Position control devices control movement of the sensors and brackets along
the rails. The position control device can comprise a motorized ballscrew as illustrated,
pneumatic cylinder, or the like, which can but need not necessarily provide position
feedback data to the control system 140. The sensors can thus be adapted to move
parallel to the axis of the shafts 70 so that they can be located at positions corresponding
to each of the lanes of the parent rolls. The first and second sensors 130, 132
are desirably capable of moving independently from one another.
Various sequences for unwinding lanes 22 from the parent
rolls 30, 32 are possible and particular sequences will be described in relation
to Figure 6. The lanes 22 of the first parent roll 30 have been labeled L1 through
L5, where L5 is closest to the backing plate 80. Similarly, the lanes 22 of the
second parent roll 32 have been labeled L6 through L10, where L10 is closest to
the backing plate 80. It should be understood that the rolls can comprise any number
of two or more lanes and that the illustrated embodiment includes five lanes 22
per roll solely for purposes of explanation.
In one embodiment, the lanes 22 can be unwound from the
parent rolls 30, 32 in a sequence that alternates back and forth between the rolls
one lane at a time. For example, the sequence can be L1, L6, L2, L7, L3, L8, L4,
L9, L5 and L10. While L1 is being unwound, L2 through L5 remain on the first parent
roll. The beginning of L6 is spliced to the tail of L1; the beginning of L2 is spliced
to the tail of L6; and so forth. Of course, other variations include reversing the
starting order of the rolls, unwinding the rolls from the drive side toward the
operator side, or the like. Additionally, the idler rolls 86 and 94 and the sensors
130 and 132 could be maintained stationary while the parent rolls 30, 32 are moved
to create the desired relative movement. Accordingly, references herein to positioning
or moving the idler rolls or sensors also encompasses positioning or moving the
parent rolls to create, such relative movement.
After each selected lane is torn from the remaining lanes
and fully unwound, the position of the idler roll 86, 94 can be changed to correspond
to the position of the next lane to be unwound from the same parent roll. Further,
the position of the sensor 130, 132 for the roll being unwound can be changed to
correspond to the position of the next lane to be unwound from the same parent roll.
These operations can be completed after splicing the finished lane to the head of
a lane on another parent roll and during the run time of the lane from the other
parent roll. Desirably, the sensor can detect the position of the next lane to be
unwound from the roll and the position of the idler roll can be established based
on the position detected by the sensor. After a sensor 130 or 132 is in position,
the sensor can provide diameter information, which in combination with a festoon
38 position feedback signal, can be used to modulate roll unwind speed. The sensor
can also provide a signal to initiate a splice sequence. The driven roll 40 feeds
the web based on machine speed, and the speed of the driven roll is trimmed by the
position of the dancer roll 42, as is known in the art.
It will be appreciated that details of the foregoing embodiments,
given for purposes of illustration, are not to be construed as limiting the scope
of this invention. Although only a few exemplary embodiments of this invention have
been described in detail above, those skilled in the art will readily appreciate
that many modifications are possible in the exemplary embodiments without materially
departing from the novel teachings and advantages of this invention. Accordingly,
all such modifications are intended to be included within the scope of this invention,
which is defined in the following claims and all equivalents thereto. Further, it
is recognized that many embodiments may be conceived that do not achieve all of
the advantages of some embodiments, particularly of the preferred embodiments, yet
the absence of a particular advantage shall not be construed to necessarily mean
that such an embodiment is outside the scope of the present invention.