MACHINE SYSTEMS AND METHODS FOR MAKING RANDOM FIBER WEBS

A method of forming a random fiber web using pneumatic fiber feeding system is disclosed. The method includes providing a plurality of moveable apparatuses including a lickerin and a feeder, the lickerin configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin by the feeder. The method also includes doffing the plurality of fibers from the lickerin at a doffing location within the system. The method also includes communicating an air supply to entrain the plurality of fibers with the air supply after the doffing. The method also includes controlling the air supply within a flow path between the lickerin and a collector. The method also includes collecting the plurality of fibers from the air supply on a collector to form the random fiber web.

BACKGROUND

The present disclosure relates to methods, systems and machines for forming random fiber webs. More particularly, it relates to machines, systems and methods for creating non-woven air-laid webs.

In general, various machines, systems and methods are known for making random fiber webs for random fiber articles that are used for various purposes. Cleaning and abrading apparatuses are partially formed of random fiber webs. Additionally, disposable absorbent products such as mortuary, veterinary and personal care absorbent products such as diapers, feminine pads, adult incontinence products, and training pants often include one or more layers of random fiber web materials, especially liquid absorbent fiber web materials.

DETAILED DESCRIPTION

Aspects of the present disclosure relate to machines, systems and methods for manufacturing random fiber webs.

Aspects of the present disclosure are directed toward machines, systems and methods of making non-woven air-laid webs. One known machine10for creating a non-woven air-laid web is shown in reference toFIG.1. Such machine10relies on an initial random fiber mat that is fed to a rotating lickerin12such as by a feed roll14. The lickerin12is configured to comb individual fibers from the initial random fiber mat (not shown inFIG.1). The lickerin12then doffs the combed fibers therefrom using centrifugal force and the combed fibers enter an air supply AS flowing past the lickerin12and a saber roll16. The doffed fibers are carried entrained in the air supply (hereinafter AS) to a condenser18. The fibers are deposited on the condenser18in a random fashion to form the non-woven fiber web (not shown inFIG.1).

Unfortunately, the above described machine often has a non-uniform deposition of the fibers on the condenser18. This has led to further costly processing steps to create a more uniform web deposition. For example, with the machine ofFIG.1, portions of the non-woven fiber web such as along the cross-web edge regions thereof may be removed due to the non-uniform deposition of the fibers on the condenser18.

The present inventors have recognized machines which modify the machine ofFIG.1to provide for a more uniform deposition of the fibers on condenser18. Such machines reduce processing costs and can reduce the need for further post deposition steps. One realization of the present inventors was the machine ofFIG.1was doffing an undesirable amount of the combed fibers against one or both of a doffer plate20and a lower slide plate22. These fibers were not being entrained in the air supply AS and clumped together rolling down one or both of the doffer plate20and the lower slide plate22to the condenser18. This was suspected as one cause of the non-uniform deposition discussed above. In response, the present inventors propose various solutions, machines and the like, including those with the doffer plate and/or the lower slide plate being removed or having a modified geometry with respect to the machine ofFIG.1.

The present inventors have also realized other components and machine embodiments that allow for an improved more uniform deposition of the fibers on the condenser, which are described herein in brief, and are described in greater detail in PCT Patent Application Ser. No. US2019/045603 (based on U.S. Provisional Patent Application 62/717,069), and in PCT Patent Application Ser. No. US2019/045604 (based on U.S. Provisional Patent Application 62/717,095), both filed Aug. 8, 2019 and both incorporated by reference herein.

These components variously include the addition of a seal having a reverse orientation relative to a direction of rotation of the condenser, one or more ports in a housing of the machine that allow for viewing of the doffing of the fibers and/or lay-up of the fibers on the condenser, addition of a nose bar and/or nose bar extension that changes the doffing point of the fibers into the air stream, the addition of various air venting passages in the housing, a doffer plate and/or the lower slide plate configured to facilitate venting and/or air intake into and/or out of the air supply to name but a few. Further components and machines embodiments are disclosed herein and discussed with reference to the FIGURES.

FIG.1illustrates portions of the known machine10for forming a random fiber web and has been previously discussed above. In such machine10, the webs are suitable for producing non-woven fabrics by known chemical or mechanical bonding treatments. For example, dry formed structures may be chemically bonded by known means such as the application of adhesives by spray or by saturation, also bonding may be accomplished by the use of fibers, which can have a low melting point and form a bond to non-adhesive fibers by heat and pressure. Mechanical bonding may be carried out by needling, stitch bonding, print bonding or the like. The quality of any non-woven fabric produced by these finishing methods depends upon the quality and uniformity of the web structure which is to be treated or finished.

Still referring toFIG.1, the processes described herein can be run at high volume. For example, with the machine10, doffed fibers can be projected at an initial velocity of up to 5,000 feet per minute by the lickerin12, which can rotate at the same velocity. Velocities of up to 20,000 feet per minute are not uncommon for the lickerin12. Doffed fibers can entrain with the air supply AS passing adjacent the lickerin12. The air supply AS, with the doffed fibers entrained therein, passes from adjacent the lickerin12into a chamber23that is partially defined by the doffer plate20and the lower slide plate22. These two plates typically have an angle of less than 15° initially. However, the doffer plate20and the lower slide plate22are angled relative to one another such that the chamber23increases in its cross-section from adjacent the lickerin12to adjacent the condenser18. The air supply AS can be controlled so that the doffed fibers are projected into air supply AS with an average velocity of the air flow in the air supply AS being between 0.5 and 1.5 times the initial fiber velocity. The doffed fibers are preferably projected onto the condenser18at a rate of between 3 and 30 pounds per hour per inch of machine width or air flow width, although the machine10can be suitable for slower and higher rates of operation. Large volumes of air are typically used as the air supply AS to convey the doffed fibers to the condenser18. Operating with 20 to 30 times weight of air to weight of fiber processed per unit of time, at standard conditions of density and temperature (0.075 lbs. per cu. ft. at 70° F. and 29.92″ Hg) is typical.

It is desired that the air supply AS have uniform velocity, low turbulence, with a stable air stream, free from vorticities, in the direction of movement of the lickerin12. Unfortunately, such is not always the case with machine10. It was previously thought with the design of the channel/chamber that convey the air supply AS should be shaped to create a venturi in the region25adjacent the lickerin12where the fibers are doffed upstream of the chamber23. Furthermore, a boundary layer which is formed around the surface of the lickerin12can be interrupted by the use of a doffing bar24, which is situated adjacent the chamber23at a point of maximum shear just below the lickerin12at the start of the chamber23(sometimes called the expansion chamber). The doffing bar24is configured to provide a controlled low level of turbulence in the air supply AS through which the doffed fibers pass.

A nose bar26can be utilized and positioned at a small distance from the surface of the lickerin12to provide a narrow passage where the fibers are carried on hooks, projections or pieces of the wire covering or a cylinder surface of the lickerin12to a point of projection (called a doffing point or doffing location) into the venturi25and the air supply AS. The saber roll16can be positioned adjacent the nose bar26and the lickerin12and can be positioned in and adjacent the air supply AS. The saber roll16can be journaled for eccentric movement in the side housings of the machine10. The saber roll16spreads the flow of the air supply AS and aids in doffing the fibers from the lickerin12. The eccentric mounting of the saber roll16allows of varying the space between the lickerin12and the saber roll16so as to restrict the air supply AS to the doffing location.

As discussed above, the present inventors have recognized components which modify the machine10ofFIG.1to provide for a more uniform deposition of the fibers on the condenser. More particularly, the present inventors recognized with the machine10ofFIG.1, the doffing location and doffing trajectory is undesirable, and typically leads to a non-uniform deposition of the fibers on the condenser18due to at least some of the fibers being doffed toward and contacting the doffer plate20and/or the lower slide plate22and becoming jumbled and entangled together. Furthermore, the present inventors recognized the machine10ofFIG.1is susceptible to turbulent airflow, air flow surges and/or vortices due to factors including a fully enclosed expansion chamber and fully enclosed other portions of a channel that communicates the air supply AS within the machine10. The use of the venturi25at and just after the doffing location was also determined by the present inventors to be unnecessary in all embodiments. The present inventors also recognize modifications to the expansion chamber geometry, and indeed, in some cases elimination or modification of the doffer plate20and/or the lower slide plate22can be desirable.

FIG.2shows a highly schematic method100of forming a random fiber web using a pneumatic fiber feeding system. The method can include providing a plurality of rotatable rolls. These rotatable rolls can include a feed roll104, a lickerin roll106, and a saber roll108. The term “roll” as used herein is broadly defined to mean any of a moveable, driven or feed type apparatus such as a belt, and is therefore not limited only to rotatable apparatuses such as a roll. The lickerin roll106can be configured with hooks, projections and/or other features to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin roll106by the feed roll104. The saber roll108can be moveably positioned adjacent (within less than an inch to a few inches of) the lickerin roll106.

The system100can include doffing the plurality of fibers from the lickerin roll at a doffing location within a system. The method100can further include communicating an air supply to entrain the plurality of fibers with the air supply after the doffing. Additionally, the system100can include collecting the plurality of fibers from the air supply to form the random fiber web. Such collection of the fibers can occur at a collector110(also call a condenser). The collector can comprise a moveable apparatus such as a roll or belt that can move to gather the laid-up fibers to form the new random fiber web as they fall to the collector110.

The air supply AS with the plurality of fibers entrained therein can pass through a channel (also called a chamber, space or volume herein) that is downstream (in terms of a direction of flow of the air supply AS) from adjacent the lickerin roll106and the saber roll108. This channel can extend from adjacent the lickerin roll106and the saber roll108to adjacent the collector110. The channel can be at least partially defined by a housing112(this housing112can include the doffer plate, the lower slide plate, and/or the side housings as previously described herein).

As has been previously discussed and will be further discussed herein subsequently, the present inventors have modified system10ofFIG.1.FIG.2shows just some system and component modifications that the present inventors contemplate. These modifications and components are further described in reference toFIGS.3-7. Further components and modifications are discussed in co-pending applications PCT Patent Application Ser. No. US2019/045603, and PCT Patent Application Ser. No. US2019/045604, both filed Aug. 8, 2019, the entire disclosures of which are incorporated herein in its entirety.

Specifically, as described in PCT Application Ser. No. US2019/045604, a nose bar assembly can include an extended nose bar between the feed roll104and the lickerin roll106. System100can also include providing for an air deflector assembly positioned between the lickerin roll106and the saber roll108. The air deflector assembly can be mounted to a housing of the machine adjacent to the feed roll104and can extend into the space to adjacent the lickerin roll106. System100can also include providing a damper118adjacent the saber roll108to control air flow around the saber roll108. The system100can include providing an airfoil that can be used in lieu of the saber roll108.

Four other possible additions to the system100that can be utilized are described in PCT Patent Application Ser. No. US2019/045603. Such additions can include providing for a nose bar assembly that can include an extended nose bar between the feed roll104and the lickerin roll106. The nose bar assembly can have texturing (i.e. can include surface features such as from carding wires, etc.) in some embodiments. System100can include providing for a vent in a saber roll assembly (i.e. a vent between the saber roll108and a saber roll end cap that is rotatably mounted in the side housing). The system100can include providing one or more viewing ports in the housing112. These one or more viewing ports can be positioned adjacent the doffing location (e.g., adjacent the lickerin roll106) and adjacent the collector110, for example. These viewing ports allow for viewing/monitoring of the doffing of the fibers and/or viewing/monitoring of the fibers as they fall and form the random fiber web on the collector110, for example. Additionally, system100can provide a reverse seal that engages the collector110and further is mounted to the lower slide plate. This reverse seal can be shaped to extend from the lower slide plate and can be oriented with a tip that extends in a direction generally opposite of a direction of rotation of the collector110.

These additions can be utilized together, alone or in various combinations as described in PCT Patent Application Ser. No. US2019/045603. They may also be utilized in combinations, or sub-combinations with the improvements of PCT Patent Application Ser. No. US2019/045604. Further, combinations or sub-combinations of both PCT Patent Application Ser. No. US2019/045603 and PCT Patent Application Ser. No. US2019/045604 may be utilized with the improvements discussed herein.

FIG.2illustrates steps150and160, which includes an open chamber150for air flow and a control160for air flow. In the system ofFIG.1, air flow is provided solely from air supply AS and is collected by a vacuum in collector110. However, in at least some embodiments described herein, housing112is designed to have an open chamber150for less restricted air flow. As described above, some problems with the design ofFIG.1is the tendency for fibers to collide either with doffer plate20or lower slide plate22. A more open chamber150within housing112allows for less restricted flow, reducing the likelihood of air, or entrained fibers, colliding with components of system100between the lickerin roll106and collector110.

Additionally, in some embodiments, air flow control160is provided for air from an air supply, such as air supply AS. Air is provided from air supply AS, as illustrated inFIG.1, between saber roll16and lickerin roll12and forced down to collector18. In system10there is no additional source of air either to enter or leave the system. This can cause the air flow within the housing to behave in unpredictable ways, often resulting in entrained fibers clumping and resulting in an uneven web. In some embodiments, therefore, static air control is provided, such that air can enter or leave the system from sources other than air supply AS. Additionally, the direction of air flow within housing112is at least partially controllable by a dynamic air control mechanism located within the housing.

FIG.3Ashows a machine220can include a feed apparatus (e.g., rotatable feed roll204), a lickerin (e.g., lickerin roll206) a saber (e.g., the saber roll208), a channel226and the collector210. The rotatable lickerin roll206can be configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin roll206by the feed roll204. The lickerin roll206can be configured to doff the plurality of fibers from the lickerin roll206. The rotatable saber roll208can be positioned adjacent the feed roll204and the lickerin roll206. The channel226can communicate the air supply AS to the space228defined between the lickerin roll206and the saber roll208. The space228can include a doffing location where the doff of the plurality of fibers from the lickerin roll206occurs. The rotatable collector210can be positioned to capture the plurality of fibers once doffed into the air supply AS. The plurality of fibers, when laid-up, form the random fiber web on the collector210.

The air deflector assembly216can comprise a thin sheet of material that is positioned between the lickerin roll206and the saber roll208. The air deflector assembly216can be mounted to a housing portion240of the machine220adjacent to the feed roll204and can extend into the space228to adjacent (within less than an inch or less than a few inches) of the lickerin roll204.

The embodiment ofFIG.3Afurther shows the nose bar assembly214positioned adjacent the lickerin roll206and extending along the lickerin roll206toward the saber roll208for the machine220. More particularly, the nose bar assembly214can include a nose bar230and a nose bar extension232. The nose bar extension232and the nose bar230can be coupled together, or may be a single component. The nose bar extension232can extend along the lickerin roll206and toward the saber roll208.

In the embodiment ofFIG.3A, the nose bar extension232can be separated from the space226by the air deflector assembly216, which is positioned between the nose bar extension232(and indeed extends between the lickerin roll206and the saber roll208) and the space226. InFIG.3A, the air deflector assembly216is positioned and configured to deflect the air supply AS away from the nose bar extension232and the doffing location (i.e., the location where the plurality of fibers are doffed from the lickerin roll206). Thus, the doffing location can be located in a second space234defined between the lickerin roll206and the air deflector assembly216adjacent a termination point of the nose bar extension232. Thus, the doffing location is in the second space234and is not directly in the air supply AS in the space228due to the presence of the air deflector assembly216. Put another way, in the embodiment ofFIG.3A, the doffing location is not directly positioned in the air supply AS but is separated therefrom by the air deflector assembly216.

The nose bar assembly214can be positioned at least partially between the feed roll204and the lickerin roll206and can extend into the second space234. The nose bar assembly214can be positioned adjacent to (within less than an inch or less than a few inches) and can extend around a portion of the circumference of the lickerin roll up to 170 degrees. The nose bar assembly214, and in particular, the nose bar extension232can control the doffing location and trajectory. The nose bar extension232can be shaped and positioned such that the doffing location and trajectory is shifted so the plurality of fibers clear the air deflector assembly216, the doffer plate20and/or the lower slide plate22and are better positioned to entrain in the air supply AS after passing the end236of the air deflector assembly216.

FIG.3Billustrates a machine320having an air supply AS, a feed apparatus (e.g., rotatable feed roll304), a lickerin (e.g., lickerin roll306) a saber (e.g., saber roll308), a channel326including a space328and the collector310. The rotatable lickerin roll306can be configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin roll306by the feed roll304. The lickerin roll306can be configured to doff the plurality of fibers from the lickerin roll306. The rotatable saber roll308can be positioned adjacent the feed roll304and the lickerin roll306. The channel326can communicate the air supply AS to the space328defined between the lickerin roll306and the saber roll308. The space328can include a doffing location where the doff of the plurality of fibers from the lickerin roll306occurs. The rotatable collector310can be positioned to capture the plurality of fibers once doffed into the air supply AS. The plurality of fibers when laid-up form the random fiber web on the collector310.

The embodiment ofFIG.3Bshows the nose bar assembly314positioned adjacent the lickerin roll306and extending along the lickerin roll306toward the saber roll308for the machine320.FIG.3Badditionally shows the vent315in the saber roll end cap322adjacent the lickerin roll306for the machine320. As the saber roll end cap322can be moveable in the side housing, the position of the vent315can be changed relative to the lickerin roll306.FIG.3Bshows the one or more viewing ports316in the side housing of the machine320. The one or more viewing ports316can be positioned adjacent the doffing location (e.g., adjacent the lickerin roll306) and adjacent the collector310. The apparatus320can include the reverse seal318that is shaped to extend from the lower slide plate324to engage with the collector310. The reverse seal318can be oriented with a tip that extends generally in a direction opposite of a direction of rotation of the collector310.

The embodiments ofFIGS.3A and3Bboth illustrate embodiments where fibers are doffed into air supply AS and thrown toward a collector. In between the entrained fibers move through a housing with chamber barriers highlighted by boxes250. Contact with any of these chamber barriers can reduce a velocity of a moving fiber to zero, reduce the overall acceleration of the fiber, and cause it to interwine with nearby fibers, creating a clump that will result in an area of a resulting web of higher fiber density than desired. In some embodiments, such as those illustrated inFIGS.4-5, chamber barriers create a wider path for air flow through a machine, such that entrained fibers are more likely to move along a path directly from a doffing location to a collector without encountering an obstacle. The present inventors have determined the various channel designs described herein are configured to more evenly spread the air supply AS across the respective channel with the plurality of fibers entrained therein prior to the air supply reaching a collector. This allows for a more even cross-web deposition on the collector when forming the random fiber web.

FIG.4shows an embodiment of a system400that is part of a machine402that includes a drum404. InFIG.4, the doffer plate has been replaced by the drum404. The drum404can spaced from the lickerin roll and can be positioned adjacent the collector414. The drum404can include one or more passages406that communicate (for example, via openings through the cylindrical wall of drum404) with a channel408that provides for passage of the air supply AS with the plurality of fibers entrained therein downstream of the doffing location to the collector410. The one or more passages406are configured to allow an amount of the air supply AS to pass therethrough should conditions within the system400and machine402dictate. Alternatively, the one or more passages are configured to allow an ambient air from outside the machine402to pass therethrough and into the channel408.

The drum404can, in some embodiments, provide a moving surface and can be configured to move relatively closer or further away from the collector410to change the size and shape of the channel408(which is partially defined by the drum404). The drum404can rotate as indicated by arrow R inFIG.4. Such rotation can be the result of passage of the ambient air or the air supply AS in some embodiments. In other embodiments, the drum404can be powered to facilitate the rotation shown by the arrow R. Although the drum404is specifically shown inFIG.4other embodiments can contemplate a plate, nip, belt, roll, etc. or another type of apparatus that can change position to change the size and shape of the channel408. In yet further embodiments, no apparatus (e.g., no housing, plate, nip, drum, belt, roll, etc.) may be provided such that the channel808is open to the ambient in the location where the drum would be for free flow and exchange of air to or from the air supply AS.

FIG.5shows an embodiment of a system500that is part of a machine502that includes a dynamic air control mechanism560, which is illustrated inFIG.5as a rotatable doffing bar extension560that can rotate in the directions indicated by arrows562,564. In one embodiment, doffing bar extension560may have a functional rotational range of more than 30°, more than 60°, more than 90°, more than 120°, or even more than 150°. In some embodiments, the doffing bar extension560may be physically able to rotate further but does not provide a significant functional benefit. Altering a position of the extended doffing bar560influences the flow of air from AS through chamber550. By altering a position of doffing bar560and a position of lower slide plate568, an air flow path566can be influenced, allowing for better control of entrained fibers, and better consistency in the cross-web direction as fibers contact collector510.

Doffing bar560is illustrated inFIG.5as extending only part of the distance between lickerin roll506and collector510. In some embodiments, doffing bar extends at least 5%, or at least 10%, or at least 15%, or at least 20%, or at least 25%, or at least 30%, or at least 35%, or at least 40%, or at least 45% of the distance between lickerin roll506and collector510. In some embodiments, doffing bar extends further, more than 50%, more than 55%, more than 60%, more than 65%, more than 70%, more than 75%, more than 80%, more than 85%, or more than 90% of the distance between lickerin roll506and collector510.

Additionally, doffing bar560is illustrated as having a straight bar extending from a rotating portion. However, in some embodiments, the straight portion may be curved, either curved toward slide plate568or away from slide plate568.

The full perimeter of chamber550is not illustrated inFIG.5. System500may be combined with an upper drum, such as drum404ofFIG.4, in some embodiments, which may also allow for better control of air and entrained fiber movement within flow path550. Alternatively, in some embodiments a doffing plate, such as plate20ofFIG.1, may provide for an upper boundary on chamber550. The upper boundary may also be a standard glass or metal housing, in other embodiments. These and other suitable configurations are expressly contemplated. Other static and dynamic air control mechanisms may also be used in combination with the extended doffing bar560, such as any of those discussed herein, or in PCT Patent Application Ser. No. US2019/045603 (based on U.S. Provisional Patent Application 62/717,069), or in PCT Patent Application Ser. No. US2019/045604 (based on U.S. Provisional Patent Application 62/717,095). For example, position of a lower slide plate or a saber roll with respect to the lickerin roll.

FIG.6illustrates a component diagram of a nonwoven web generation system600. System600includes a fiber source602, which provides fibers to a fiber feeder610. Lickerin roll630retrieves fibers from fiber feeder610using a fiber capture mechanism634. Lickerin roll630, in one embodiment, is a rotating lickerin roll630, which rotates using a rotation mechanism632. Lickerin roll630doffs fibers, which are entrained in an air flow provided from air source620, and collected by a condenser650. Vacuum652pulls fibers into place along a crossweb direction on condenser650, which rotates using rotating mechanism654.

Air flow, from air source620, is controlled using air flow control mechanism640. Air flow control mechanism640may include a static air control642which, as used herein, is intended to describe a controller642that is generally not adjusted in between operations, but remains in a set operational position during an operation. Air flow control mechanism640may, in some embodiments, be a dynamic air control mechanism644that can be adjusted in between operations. Dynamic air control mechanisms644may also be adjustable during an operation, in some embodiments, however in-situ adjustments may not be recommended for safety reasons. Positions, movements and speed of movement, for example rotational speed of lickerin roll or condenser650, may be controlled by a control system660, which may be part of nonwoven web generation system600, or may be connected to nonwoven web generation system600through a wired or wireless connection, in some embodiments.

FIG.7A-7Dillustrate views of a doffing plate and an extended doffing bar for controlling airflow according to an embodiment of the present invention.FIGS.7A and7Billustrate views of a prior art doffing plate, for example plate20fromFIG.1. Doffing plate720, as used in prior art machines, creates an upper boundary of an air flow chamber. As illustrated inFIG.7A, doffing assembly700includes a doffing plate720has curvature and extends from a point704, where it connects to a lickerin roll, to point702, where it connects to a fiber collector. Doffing plate720connects to a doffing bar710that is at a fixed position712during operation of a system. Doffing plate720is intended have some rotation such that a gap is formed at point702, through which a formed fiber web passes through. The formed fiber web closes the gap created left by doffing plate720. While doffing plate720may rotate several degrees, less than 10° or less than 15°, for example, any gap created is intended to be sealed by a fiber web formed during operation of assembly700. Additionally, as described above, doffing plate720presents some issues with regard to free air flow from a doffing location to a collector.

In contrast,FIGS.7C and7Dillustrate views of an extended doffing bar assembly750. As illustrated inFIG.7C, an extending portion770extends from a doffing bar760, which is fixed within the system during operation. However, extending portion770is rotatable about a rotation axis780. As illustrated inFIGS.7C and7D, in some embodiments rotation is limited by a rotation path782, which may include a range of about 150° about rotation axis780. However, in other embodiments the rotation range may be larger, for example limited only by the position of doffing bar760and a lickerin roll, or the rotation range may be smaller. For example, the rotation range may be as small as 30°, or 40°, or 50°, or 60°, or 70°, or 80°, or 90°, or 100°, or 110°, or 120°, or 130° or 140°. Additionally, the rotation range may be larger than 140°, or larger than 150°. The rotation angle can also be expressed with respect to a 0° position where doffing bar760is positioned parallel to the slide plate. The rotation range, for example, can be between 0° to 30°, or more, in the direction toward the slide plate, or between 0° and 60°, or more in the direction away from the slide plate.

In the embodiments ofFIGS.7C and7D, extended doffing bar assembly750does not perform a sealing or upper boundary function. A separate boundary may also be included, in some embodiments. In some embodiments, the separate boundary is porous or otherwise configured to allow airflow between an air flow channel and the ambient environment.

A method of forming a random fiber web using pneumatic fiber feeding system is presented. The method includes providing a plurality of moveable apparatuses including a lickerin and a feeder. The lickerin is configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin by the feeder. The method also includes doffing the plurality of fibers from the lickerin at a doffing location within the system. The method also includes communicating an air supply to entrain the plurality of fibers with the air supply after the doffing. The method also includes controlling the air supply within a flow path between the lickerin and a collector. The method also includes collecting the plurality of fibers from the air supply on a collector to form the random fiber web.

Controlling the air supply within the flow path may include a static air control mechanism.

The static air control mechanism may include a vent in the saber assembly, the chamber, a doffer plate, or a lower slide plate

The static air control mechanism may include an extended nose bar between the feeder and the lickerin.

The static air control mechanism may include a reverse seal extending from a lower slide plate to the collector.

The static air control mechanism may include a drum that allows exchange between the air supply and an ambient air source.

The drum may rotate.

The static air control mechanism may include an air deflector plate.

Controlling the air supply within the flow path may include a dynamic air control mechanism.

The dynamic air control mechanism may be adjustable only when the pneumatic fiber feeding system is in a nonrunning state.

The dynamic air control mechanism may include an extended doffer bar.

The extended doffer bar may be rotatable within a chamber of the pneumatic fiber feeding system. Rotation of the extended doffer bar causes the air supply to change from a first air flow pattern within the chamber to a second air flow pattern within the chamber.

The dynamic air control mechanism comprises an air foil positioned to direct the air supply.

The method may further include controlling the amount of the air supply to at least one of the doffing location and downstream of the doffing location as defined by a direction of flow of the air supply.

Controlling the amount of air supply may include providing for one or more of a damper, a nose bar extension, an air deflector plate, an airfoil and one or more passages in a housing of the system.

A pneumatic fiber feeding system for forming a random fiber web is presented. The system includes a feeder. The system also includes a lickerin configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin by the feeder and configured to doff the plurality of fibers from the lickerin. The system also includes a channel communicating an air supply to a space adjacent the lickerin, the space including a doffing location where the doff of the plurality of fibers from the lickerin occurs. The system also includes a collector positioned to capture the plurality of fibers once doffed into the air supply, the plurality of fibers forming the random fiber web on the collector.

The system also includes an air control mechanism within the channel.

The air control mechanism may be a static air control mechanism.

The air control mechanism may be a dynamic air control mechanism.

The static air control mechanism may include a vent in the saber assembly, the chamber, a doffer plate, or a lower slide plate.

The static air control mechanism may include an extended nose bar between the feeder and the lickerin.

The static air control mechanism may include a reverse seal extending from a lower slide plate to the collector.

The static air control mechanism may include a drum that allows exchange between the air supply and an ambient air source.

The drum may include an upper condenser.

The upper condenser may rotate.

The static air control mechanism may include an air deflector plate.

The dynamic air control mechanism may include an extended doffer bar.

The extended doffer bar may be rotatable within a chamber of the pneumatic fiber feeding system. Rotation of the extended doffer bar causes the air supply to change from a first air flow pattern within the chamber to a second air flow pattern within the chamber.

The channel downstream of the doffing location may be defined by a direction of flow of the air supply that is partially formed by a first plate. The first plate has a substantially planar surface along a channel interfacing extent thereof that is configured to substantially align with the direction of flow of the air supply.

A first end of the first plate extends beyond the extended doffer bar to adjacent the lickerin.

The system may also include one or more passages that communicate with the channel downstream of the doffing location. The one or more passages may be configured to allow both an amount of the supply air to pass therethrough and allow an amount of an ambient air to pass therethrough and into the channel.

The one or more passages may be formed by a portion of a housing enclosing the channel.

The system lay further include a deflector plate positioned adjacent the lickerin and extending into the space. The deflector plate may be positioned to keep the air supply and the plurality of fibers separated until after the doffing location.

The system may further include a nose bar assembly positioned between the lickerin and the deflector plate. The nose bar assembly may be configured to extend the doffing location past the feed roll and into a second space defined between lickerin and the deflector plate.

The system may further include an airfoil positioned in the channel that is configured to be selectively moveable toward and away from the deflector plate to selectively allow for passage of at least a portion of the supply air into the second space.

The system may further include a damper positioned in the channel and configured to be selectively moveable toward and away from a saber roll to selectively allow for passage of at least a portion of the supply air around a part of the saber roll that does not interface with the lickerin.

A pneumatic fiber feeding system for forming a random fiber web is presented. The system includes a plurality of moveable apparatuses including a lickerin and a feeder. The lickerin is configured to remove a plurality of fibers from a fibrous mat delivered to adjacent the lickerin by the feeder. The lickerin is configured to doff the plurality of fibers from the lickerin. The system also includes a channel communicating an air supply to a space adjacent the lickerin, the space including a doffing location where the doff of the plurality of fibers from the lickerin occurs. The system also includes a collector positioned to capture the plurality of fibers once doffed into the main air supply, the plurality of fibers forming the random fiber web on the collector. The system also includes an air control mechanism within the channel.

The system may also include a drum, one or more passages that communicate with the channel downstream of the doffing location, or a restriction in the channel downstream of the doffing location and prior to the collector.

The air control mechanism may direct the air supply toward the collector.

The air control mechanism may be adjustable.

The air control mechanism may be rotatable.

The air control mechanism may extend within the channel toward the collector. Adjusting the air control mechanism may change a flow path of the air supply through the channel.

The air control mechanism may extend less than halfway between the lickerin and the collector.

The air control mechanism may extend more than halfway between the lickerin and the collector.

The air control mechanism may include an extending portion that is substantially flat.

The air control mechanism may include an extending portion that is curved.

The air control mechanism may extend from a doffing bar and rotates about an axis defined by the doffing bar.

The system may also include a deflector plate positioned adjacent the lickerin and extending into the space. The deflector plate may be positioned to keep the air supply and the plurality of fibers separated until after the doffing location.

The system may also include a nose bar assembly positioned between the lickerin and the deflector plate. The nose bar assembly may be configured to extend the doffing location past the feed roll and into a second space defined between lickerin and the deflector plate.

The system may also include an airfoil positioned in the channel. The airfoil may be configured to be selectively moveable toward and away from the deflector plate to selectively allow for passage of at least a portion of the supply air into the second space.

The system may also include a damper positioned in the channel and configured to be selectively moveable toward and away from a saber roll to selectively allow for passage of at least a portion of the supply air around a part of the saber roll that does not interface with the lickerin.

The system may also include a passage between the channel and a source of an ambient air.

As Used Herein:

The term “a”, “an”, and “the” are used interchangeably with “at least one” to mean one or more of the elements being described.

The term “and/or” means either or both. For example, “A and/or B” means only A, only B, or both A and B.

The terms “including,” “comprising,” or “having,” and variations thereof, are meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

The term “adjacent” refers to the relative position of two elements, such as, for example, two layers, that are close to each other and may or may not be necessarily in contact with each other or that may have one or more layers separating the two elements as understood by the context in which “adjacent” appears.

All scientific and technical terms used herein have meanings commonly used in the art unless otherwise specified. The definitions provided herein are to facilitate understanding of certain terms used frequently in this application and are not meant to exclude a reasonable interpretation of those terms in the context of the present disclosure.

Unless otherwise indicated, all numbers in the description and the claims expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviations found in their respective testing measurements.

The term “substantially” means within 20 percent (in some cases within 15 percent, in yet other cases within 10 percent, and in yet other cases within 5 percent) of the attribute being referred to. Thus, a value A is “substantially similar” to a value B if the value A is within plus/minus one or more of 5%, 10%, 20% of the value A.

The recitation of numerical ranges by endpoints includes all numbers subsumed within that range (e.g. a range from 1 to 5 includes, for instance, 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5) and any range within that range.